diff options
Diffstat (limited to 'net/bridge/netfilter')
24 files changed, 5534 insertions, 0 deletions
diff --git a/net/bridge/netfilter/Kconfig b/net/bridge/netfilter/Kconfig new file mode 100644 index 00000000..a9aff9c7 --- /dev/null +++ b/net/bridge/netfilter/Kconfig @@ -0,0 +1,221 @@ +# +# Bridge netfilter configuration +# + +menuconfig BRIDGE_NF_EBTABLES + tristate "Ethernet Bridge tables (ebtables) support" + depends on BRIDGE && NETFILTER + select NETFILTER_XTABLES + help + ebtables is a general, extensible frame/packet identification + framework. Say 'Y' or 'M' here if you want to do Ethernet + filtering/NAT/brouting on the Ethernet bridge. + +if BRIDGE_NF_EBTABLES + +# +# tables +# +config BRIDGE_EBT_BROUTE + tristate "ebt: broute table support" + help + The ebtables broute table is used to define rules that decide between + bridging and routing frames, giving Linux the functionality of a + brouter. See the man page for ebtables(8) and examples on the ebtables + website. + + To compile it as a module, choose M here. If unsure, say N. + +config BRIDGE_EBT_T_FILTER + tristate "ebt: filter table support" + help + The ebtables filter table is used to define frame filtering rules at + local input, forwarding and local output. See the man page for + ebtables(8). + + To compile it as a module, choose M here. If unsure, say N. + +config BRIDGE_EBT_T_NAT + tristate "ebt: nat table support" + help + The ebtables nat table is used to define rules that alter the MAC + source address (MAC SNAT) or the MAC destination address (MAC DNAT). + See the man page for ebtables(8). + + To compile it as a module, choose M here. If unsure, say N. +# +# matches +# +config BRIDGE_EBT_802_3 + tristate "ebt: 802.3 filter support" + help + This option adds matching support for 802.3 Ethernet frames. + + To compile it as a module, choose M here. If unsure, say N. + +config BRIDGE_EBT_AMONG + tristate "ebt: among filter support" + help + This option adds the among match, which allows matching the MAC source + and/or destination address on a list of addresses. Optionally, + MAC/IP address pairs can be matched, f.e. for anti-spoofing rules. + + To compile it as a module, choose M here. If unsure, say N. + +config BRIDGE_EBT_ARP + tristate "ebt: ARP filter support" + help + This option adds the ARP match, which allows ARP and RARP header field + filtering. + + To compile it as a module, choose M here. If unsure, say N. + +config BRIDGE_EBT_IP + tristate "ebt: IP filter support" + help + This option adds the IP match, which allows basic IP header field + filtering. + + To compile it as a module, choose M here. If unsure, say N. + +config BRIDGE_EBT_IP6 + tristate "ebt: IP6 filter support" + depends on BRIDGE_NF_EBTABLES && IPV6 + help + This option adds the IP6 match, which allows basic IPV6 header field + filtering. + + To compile it as a module, choose M here. If unsure, say N. + +config BRIDGE_EBT_LIMIT + tristate "ebt: limit match support" + help + This option adds the limit match, which allows you to control + the rate at which a rule can be matched. This match is the + equivalent of the iptables limit match. + + If you want to compile it as a module, say M here and read + <file:Documentation/kbuild/modules.txt>. If unsure, say `N'. + +config BRIDGE_EBT_MARK + tristate "ebt: mark filter support" + help + This option adds the mark match, which allows matching frames based on + the 'nfmark' value in the frame. This can be set by the mark target. + This value is the same as the one used in the iptables mark match and + target. + + To compile it as a module, choose M here. If unsure, say N. + +config BRIDGE_EBT_PKTTYPE + tristate "ebt: packet type filter support" + help + This option adds the packet type match, which allows matching on the + type of packet based on its Ethernet "class" (as determined by + the generic networking code): broadcast, multicast, + for this host alone or for another host. + + To compile it as a module, choose M here. If unsure, say N. + +config BRIDGE_EBT_STP + tristate "ebt: STP filter support" + help + This option adds the Spanning Tree Protocol match, which + allows STP header field filtering. + + To compile it as a module, choose M here. If unsure, say N. + +config BRIDGE_EBT_VLAN + tristate "ebt: 802.1Q VLAN filter support" + help + This option adds the 802.1Q vlan match, which allows the filtering of + 802.1Q vlan fields. + + To compile it as a module, choose M here. If unsure, say N. +# +# targets +# +config BRIDGE_EBT_ARPREPLY + tristate "ebt: arp reply target support" + depends on BRIDGE_NF_EBTABLES && INET + help + This option adds the arp reply target, which allows + automatically sending arp replies to arp requests. + + To compile it as a module, choose M here. If unsure, say N. + +config BRIDGE_EBT_DNAT + tristate "ebt: dnat target support" + help + This option adds the MAC DNAT target, which allows altering the MAC + destination address of frames. + + To compile it as a module, choose M here. If unsure, say N. + +config BRIDGE_EBT_MARK_T + tristate "ebt: mark target support" + help + This option adds the mark target, which allows marking frames by + setting the 'nfmark' value in the frame. + This value is the same as the one used in the iptables mark match and + target. + + To compile it as a module, choose M here. If unsure, say N. + +config BRIDGE_EBT_REDIRECT + tristate "ebt: redirect target support" + help + This option adds the MAC redirect target, which allows altering the MAC + destination address of a frame to that of the device it arrived on. + + To compile it as a module, choose M here. If unsure, say N. + +config BRIDGE_EBT_SNAT + tristate "ebt: snat target support" + help + This option adds the MAC SNAT target, which allows altering the MAC + source address of frames. + + To compile it as a module, choose M here. If unsure, say N. +# +# watchers +# +config BRIDGE_EBT_LOG + tristate "ebt: log support" + help + This option adds the log watcher, that you can use in any rule + in any ebtables table. It records info about the frame header + to the syslog. + + To compile it as a module, choose M here. If unsure, say N. + +config BRIDGE_EBT_ULOG + tristate "ebt: ulog support (OBSOLETE)" + help + This option enables the old bridge-specific "ebt_ulog" implementation + which has been obsoleted by the new "nfnetlink_log" code (see + CONFIG_NETFILTER_NETLINK_LOG). + + This option adds the ulog watcher, that you can use in any rule + in any ebtables table. The packet is passed to a userspace + logging daemon using netlink multicast sockets. This differs + from the log watcher in the sense that the complete packet is + sent to userspace instead of a descriptive text and that + netlink multicast sockets are used instead of the syslog. + + To compile it as a module, choose M here. If unsure, say N. + +config BRIDGE_EBT_NFLOG + tristate "ebt: nflog support" + help + This option enables the nflog watcher, which allows to LOG + messages through the netfilter logging API, which can use + either the old LOG target, the old ULOG target or nfnetlink_log + as backend. + + This option adds the nflog watcher, that you can use in any rule + in any ebtables table. + + To compile it as a module, choose M here. If unsure, say N. + +endif # BRIDGE_NF_EBTABLES diff --git a/net/bridge/netfilter/Makefile b/net/bridge/netfilter/Makefile new file mode 100644 index 00000000..07186995 --- /dev/null +++ b/net/bridge/netfilter/Makefile @@ -0,0 +1,34 @@ +# +# Makefile for the netfilter modules for Link Layer filtering on a bridge. +# + +obj-$(CONFIG_BRIDGE_NF_EBTABLES) += ebtables.o + +# tables +obj-$(CONFIG_BRIDGE_EBT_BROUTE) += ebtable_broute.o +obj-$(CONFIG_BRIDGE_EBT_T_FILTER) += ebtable_filter.o +obj-$(CONFIG_BRIDGE_EBT_T_NAT) += ebtable_nat.o + +#matches +obj-$(CONFIG_BRIDGE_EBT_802_3) += ebt_802_3.o +obj-$(CONFIG_BRIDGE_EBT_AMONG) += ebt_among.o +obj-$(CONFIG_BRIDGE_EBT_ARP) += ebt_arp.o +obj-$(CONFIG_BRIDGE_EBT_IP) += ebt_ip.o +obj-$(CONFIG_BRIDGE_EBT_IP6) += ebt_ip6.o +obj-$(CONFIG_BRIDGE_EBT_LIMIT) += ebt_limit.o +obj-$(CONFIG_BRIDGE_EBT_MARK) += ebt_mark_m.o +obj-$(CONFIG_BRIDGE_EBT_PKTTYPE) += ebt_pkttype.o +obj-$(CONFIG_BRIDGE_EBT_STP) += ebt_stp.o +obj-$(CONFIG_BRIDGE_EBT_VLAN) += ebt_vlan.o + +# targets +obj-$(CONFIG_BRIDGE_EBT_ARPREPLY) += ebt_arpreply.o +obj-$(CONFIG_BRIDGE_EBT_MARK_T) += ebt_mark.o +obj-$(CONFIG_BRIDGE_EBT_DNAT) += ebt_dnat.o +obj-$(CONFIG_BRIDGE_EBT_REDIRECT) += ebt_redirect.o +obj-$(CONFIG_BRIDGE_EBT_SNAT) += ebt_snat.o + +# watchers +obj-$(CONFIG_BRIDGE_EBT_LOG) += ebt_log.o +obj-$(CONFIG_BRIDGE_EBT_ULOG) += ebt_ulog.o +obj-$(CONFIG_BRIDGE_EBT_NFLOG) += ebt_nflog.o diff --git a/net/bridge/netfilter/ebt_802_3.c b/net/bridge/netfilter/ebt_802_3.c new file mode 100644 index 00000000..2a449b7a --- /dev/null +++ b/net/bridge/netfilter/ebt_802_3.c @@ -0,0 +1,72 @@ +/* + * 802_3 + * + * Author: + * Chris Vitale csv@bluetail.com + * + * May 2003 + * + */ +#include <linux/module.h> +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter_bridge/ebtables.h> +#include <linux/netfilter_bridge/ebt_802_3.h> + +static bool +ebt_802_3_mt(const struct sk_buff *skb, struct xt_action_param *par) +{ + const struct ebt_802_3_info *info = par->matchinfo; + const struct ebt_802_3_hdr *hdr = ebt_802_3_hdr(skb); + __be16 type = hdr->llc.ui.ctrl & IS_UI ? hdr->llc.ui.type : hdr->llc.ni.type; + + if (info->bitmask & EBT_802_3_SAP) { + if (FWINV(info->sap != hdr->llc.ui.ssap, EBT_802_3_SAP)) + return false; + if (FWINV(info->sap != hdr->llc.ui.dsap, EBT_802_3_SAP)) + return false; + } + + if (info->bitmask & EBT_802_3_TYPE) { + if (!(hdr->llc.ui.dsap == CHECK_TYPE && hdr->llc.ui.ssap == CHECK_TYPE)) + return false; + if (FWINV(info->type != type, EBT_802_3_TYPE)) + return false; + } + + return true; +} + +static int ebt_802_3_mt_check(const struct xt_mtchk_param *par) +{ + const struct ebt_802_3_info *info = par->matchinfo; + + if (info->bitmask & ~EBT_802_3_MASK || info->invflags & ~EBT_802_3_MASK) + return -EINVAL; + + return 0; +} + +static struct xt_match ebt_802_3_mt_reg __read_mostly = { + .name = "802_3", + .revision = 0, + .family = NFPROTO_BRIDGE, + .match = ebt_802_3_mt, + .checkentry = ebt_802_3_mt_check, + .matchsize = sizeof(struct ebt_802_3_info), + .me = THIS_MODULE, +}; + +static int __init ebt_802_3_init(void) +{ + return xt_register_match(&ebt_802_3_mt_reg); +} + +static void __exit ebt_802_3_fini(void) +{ + xt_unregister_match(&ebt_802_3_mt_reg); +} + +module_init(ebt_802_3_init); +module_exit(ebt_802_3_fini); +MODULE_DESCRIPTION("Ebtables: DSAP/SSAP field and SNAP type matching"); +MODULE_LICENSE("GPL"); diff --git a/net/bridge/netfilter/ebt_among.c b/net/bridge/netfilter/ebt_among.c new file mode 100644 index 00000000..8b84c581 --- /dev/null +++ b/net/bridge/netfilter/ebt_among.c @@ -0,0 +1,229 @@ +/* + * ebt_among + * + * Authors: + * Grzegorz Borowiak <grzes@gnu.univ.gda.pl> + * + * August, 2003 + * + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#include <linux/ip.h> +#include <linux/if_arp.h> +#include <linux/module.h> +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter_bridge/ebtables.h> +#include <linux/netfilter_bridge/ebt_among.h> + +static bool ebt_mac_wormhash_contains(const struct ebt_mac_wormhash *wh, + const char *mac, __be32 ip) +{ + /* You may be puzzled as to how this code works. + * Some tricks were used, refer to + * include/linux/netfilter_bridge/ebt_among.h + * as there you can find a solution of this mystery. + */ + const struct ebt_mac_wormhash_tuple *p; + int start, limit, i; + uint32_t cmp[2] = { 0, 0 }; + int key = ((const unsigned char *)mac)[5]; + + memcpy(((char *) cmp) + 2, mac, 6); + start = wh->table[key]; + limit = wh->table[key + 1]; + if (ip) { + for (i = start; i < limit; i++) { + p = &wh->pool[i]; + if (cmp[1] == p->cmp[1] && cmp[0] == p->cmp[0]) + if (p->ip == 0 || p->ip == ip) + return true; + } + } else { + for (i = start; i < limit; i++) { + p = &wh->pool[i]; + if (cmp[1] == p->cmp[1] && cmp[0] == p->cmp[0]) + if (p->ip == 0) + return true; + } + } + return false; +} + +static int ebt_mac_wormhash_check_integrity(const struct ebt_mac_wormhash + *wh) +{ + int i; + + for (i = 0; i < 256; i++) { + if (wh->table[i] > wh->table[i + 1]) + return -0x100 - i; + if (wh->table[i] < 0) + return -0x200 - i; + if (wh->table[i] > wh->poolsize) + return -0x300 - i; + } + if (wh->table[256] > wh->poolsize) + return -0xc00; + return 0; +} + +static int get_ip_dst(const struct sk_buff *skb, __be32 *addr) +{ + if (eth_hdr(skb)->h_proto == htons(ETH_P_IP)) { + const struct iphdr *ih; + struct iphdr _iph; + + ih = skb_header_pointer(skb, 0, sizeof(_iph), &_iph); + if (ih == NULL) + return -1; + *addr = ih->daddr; + } else if (eth_hdr(skb)->h_proto == htons(ETH_P_ARP)) { + const struct arphdr *ah; + struct arphdr _arph; + const __be32 *bp; + __be32 buf; + + ah = skb_header_pointer(skb, 0, sizeof(_arph), &_arph); + if (ah == NULL || + ah->ar_pln != sizeof(__be32) || + ah->ar_hln != ETH_ALEN) + return -1; + bp = skb_header_pointer(skb, sizeof(struct arphdr) + + 2 * ETH_ALEN + sizeof(__be32), + sizeof(__be32), &buf); + if (bp == NULL) + return -1; + *addr = *bp; + } + return 0; +} + +static int get_ip_src(const struct sk_buff *skb, __be32 *addr) +{ + if (eth_hdr(skb)->h_proto == htons(ETH_P_IP)) { + const struct iphdr *ih; + struct iphdr _iph; + + ih = skb_header_pointer(skb, 0, sizeof(_iph), &_iph); + if (ih == NULL) + return -1; + *addr = ih->saddr; + } else if (eth_hdr(skb)->h_proto == htons(ETH_P_ARP)) { + const struct arphdr *ah; + struct arphdr _arph; + const __be32 *bp; + __be32 buf; + + ah = skb_header_pointer(skb, 0, sizeof(_arph), &_arph); + if (ah == NULL || + ah->ar_pln != sizeof(__be32) || + ah->ar_hln != ETH_ALEN) + return -1; + bp = skb_header_pointer(skb, sizeof(struct arphdr) + + ETH_ALEN, sizeof(__be32), &buf); + if (bp == NULL) + return -1; + *addr = *bp; + } + return 0; +} + +static bool +ebt_among_mt(const struct sk_buff *skb, struct xt_action_param *par) +{ + const struct ebt_among_info *info = par->matchinfo; + const char *dmac, *smac; + const struct ebt_mac_wormhash *wh_dst, *wh_src; + __be32 dip = 0, sip = 0; + + wh_dst = ebt_among_wh_dst(info); + wh_src = ebt_among_wh_src(info); + + if (wh_src) { + smac = eth_hdr(skb)->h_source; + if (get_ip_src(skb, &sip)) + return false; + if (!(info->bitmask & EBT_AMONG_SRC_NEG)) { + /* we match only if it contains */ + if (!ebt_mac_wormhash_contains(wh_src, smac, sip)) + return false; + } else { + /* we match only if it DOES NOT contain */ + if (ebt_mac_wormhash_contains(wh_src, smac, sip)) + return false; + } + } + + if (wh_dst) { + dmac = eth_hdr(skb)->h_dest; + if (get_ip_dst(skb, &dip)) + return false; + if (!(info->bitmask & EBT_AMONG_DST_NEG)) { + /* we match only if it contains */ + if (!ebt_mac_wormhash_contains(wh_dst, dmac, dip)) + return false; + } else { + /* we match only if it DOES NOT contain */ + if (ebt_mac_wormhash_contains(wh_dst, dmac, dip)) + return false; + } + } + + return true; +} + +static int ebt_among_mt_check(const struct xt_mtchk_param *par) +{ + const struct ebt_among_info *info = par->matchinfo; + const struct ebt_entry_match *em = + container_of(par->matchinfo, const struct ebt_entry_match, data); + int expected_length = sizeof(struct ebt_among_info); + const struct ebt_mac_wormhash *wh_dst, *wh_src; + int err; + + wh_dst = ebt_among_wh_dst(info); + wh_src = ebt_among_wh_src(info); + expected_length += ebt_mac_wormhash_size(wh_dst); + expected_length += ebt_mac_wormhash_size(wh_src); + + if (em->match_size != EBT_ALIGN(expected_length)) { + pr_info("wrong size: %d against expected %d, rounded to %Zd\n", + em->match_size, expected_length, + EBT_ALIGN(expected_length)); + return -EINVAL; + } + if (wh_dst && (err = ebt_mac_wormhash_check_integrity(wh_dst))) { + pr_info("dst integrity fail: %x\n", -err); + return -EINVAL; + } + if (wh_src && (err = ebt_mac_wormhash_check_integrity(wh_src))) { + pr_info("src integrity fail: %x\n", -err); + return -EINVAL; + } + return 0; +} + +static struct xt_match ebt_among_mt_reg __read_mostly = { + .name = "among", + .revision = 0, + .family = NFPROTO_BRIDGE, + .match = ebt_among_mt, + .checkentry = ebt_among_mt_check, + .matchsize = -1, /* special case */ + .me = THIS_MODULE, +}; + +static int __init ebt_among_init(void) +{ + return xt_register_match(&ebt_among_mt_reg); +} + +static void __exit ebt_among_fini(void) +{ + xt_unregister_match(&ebt_among_mt_reg); +} + +module_init(ebt_among_init); +module_exit(ebt_among_fini); +MODULE_DESCRIPTION("Ebtables: Combined MAC/IP address list matching"); +MODULE_LICENSE("GPL"); diff --git a/net/bridge/netfilter/ebt_arp.c b/net/bridge/netfilter/ebt_arp.c new file mode 100644 index 00000000..cd457b89 --- /dev/null +++ b/net/bridge/netfilter/ebt_arp.c @@ -0,0 +1,140 @@ +/* + * ebt_arp + * + * Authors: + * Bart De Schuymer <bdschuym@pandora.be> + * Tim Gardner <timg@tpi.com> + * + * April, 2002 + * + */ +#include <linux/if_arp.h> +#include <linux/if_ether.h> +#include <linux/module.h> +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter_bridge/ebtables.h> +#include <linux/netfilter_bridge/ebt_arp.h> + +static bool +ebt_arp_mt(const struct sk_buff *skb, struct xt_action_param *par) +{ + const struct ebt_arp_info *info = par->matchinfo; + const struct arphdr *ah; + struct arphdr _arph; + + ah = skb_header_pointer(skb, 0, sizeof(_arph), &_arph); + if (ah == NULL) + return false; + if (info->bitmask & EBT_ARP_OPCODE && FWINV(info->opcode != + ah->ar_op, EBT_ARP_OPCODE)) + return false; + if (info->bitmask & EBT_ARP_HTYPE && FWINV(info->htype != + ah->ar_hrd, EBT_ARP_HTYPE)) + return false; + if (info->bitmask & EBT_ARP_PTYPE && FWINV(info->ptype != + ah->ar_pro, EBT_ARP_PTYPE)) + return false; + + if (info->bitmask & (EBT_ARP_SRC_IP | EBT_ARP_DST_IP | EBT_ARP_GRAT)) { + const __be32 *sap, *dap; + __be32 saddr, daddr; + + if (ah->ar_pln != sizeof(__be32) || ah->ar_pro != htons(ETH_P_IP)) + return false; + sap = skb_header_pointer(skb, sizeof(struct arphdr) + + ah->ar_hln, sizeof(saddr), + &saddr); + if (sap == NULL) + return false; + dap = skb_header_pointer(skb, sizeof(struct arphdr) + + 2*ah->ar_hln+sizeof(saddr), + sizeof(daddr), &daddr); + if (dap == NULL) + return false; + if (info->bitmask & EBT_ARP_SRC_IP && + FWINV(info->saddr != (*sap & info->smsk), EBT_ARP_SRC_IP)) + return false; + if (info->bitmask & EBT_ARP_DST_IP && + FWINV(info->daddr != (*dap & info->dmsk), EBT_ARP_DST_IP)) + return false; + if (info->bitmask & EBT_ARP_GRAT && + FWINV(*dap != *sap, EBT_ARP_GRAT)) + return false; + } + + if (info->bitmask & (EBT_ARP_SRC_MAC | EBT_ARP_DST_MAC)) { + const unsigned char *mp; + unsigned char _mac[ETH_ALEN]; + uint8_t verdict, i; + + if (ah->ar_hln != ETH_ALEN || ah->ar_hrd != htons(ARPHRD_ETHER)) + return false; + if (info->bitmask & EBT_ARP_SRC_MAC) { + mp = skb_header_pointer(skb, sizeof(struct arphdr), + sizeof(_mac), &_mac); + if (mp == NULL) + return false; + verdict = 0; + for (i = 0; i < 6; i++) + verdict |= (mp[i] ^ info->smaddr[i]) & + info->smmsk[i]; + if (FWINV(verdict != 0, EBT_ARP_SRC_MAC)) + return false; + } + + if (info->bitmask & EBT_ARP_DST_MAC) { + mp = skb_header_pointer(skb, sizeof(struct arphdr) + + ah->ar_hln + ah->ar_pln, + sizeof(_mac), &_mac); + if (mp == NULL) + return false; + verdict = 0; + for (i = 0; i < 6; i++) + verdict |= (mp[i] ^ info->dmaddr[i]) & + info->dmmsk[i]; + if (FWINV(verdict != 0, EBT_ARP_DST_MAC)) + return false; + } + } + + return true; +} + +static int ebt_arp_mt_check(const struct xt_mtchk_param *par) +{ + const struct ebt_arp_info *info = par->matchinfo; + const struct ebt_entry *e = par->entryinfo; + + if ((e->ethproto != htons(ETH_P_ARP) && + e->ethproto != htons(ETH_P_RARP)) || + e->invflags & EBT_IPROTO) + return -EINVAL; + if (info->bitmask & ~EBT_ARP_MASK || info->invflags & ~EBT_ARP_MASK) + return -EINVAL; + return 0; +} + +static struct xt_match ebt_arp_mt_reg __read_mostly = { + .name = "arp", + .revision = 0, + .family = NFPROTO_BRIDGE, + .match = ebt_arp_mt, + .checkentry = ebt_arp_mt_check, + .matchsize = sizeof(struct ebt_arp_info), + .me = THIS_MODULE, +}; + +static int __init ebt_arp_init(void) +{ + return xt_register_match(&ebt_arp_mt_reg); +} + +static void __exit ebt_arp_fini(void) +{ + xt_unregister_match(&ebt_arp_mt_reg); +} + +module_init(ebt_arp_init); +module_exit(ebt_arp_fini); +MODULE_DESCRIPTION("Ebtables: ARP protocol packet match"); +MODULE_LICENSE("GPL"); diff --git a/net/bridge/netfilter/ebt_arpreply.c b/net/bridge/netfilter/ebt_arpreply.c new file mode 100644 index 00000000..070cf134 --- /dev/null +++ b/net/bridge/netfilter/ebt_arpreply.c @@ -0,0 +1,98 @@ +/* + * ebt_arpreply + * + * Authors: + * Grzegorz Borowiak <grzes@gnu.univ.gda.pl> + * Bart De Schuymer <bdschuym@pandora.be> + * + * August, 2003 + * + */ +#include <linux/if_arp.h> +#include <net/arp.h> +#include <linux/module.h> +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter_bridge/ebtables.h> +#include <linux/netfilter_bridge/ebt_arpreply.h> + +static unsigned int +ebt_arpreply_tg(struct sk_buff *skb, const struct xt_action_param *par) +{ + const struct ebt_arpreply_info *info = par->targinfo; + const __be32 *siptr, *diptr; + __be32 _sip, _dip; + const struct arphdr *ap; + struct arphdr _ah; + const unsigned char *shp; + unsigned char _sha[ETH_ALEN]; + + ap = skb_header_pointer(skb, 0, sizeof(_ah), &_ah); + if (ap == NULL) + return EBT_DROP; + + if (ap->ar_op != htons(ARPOP_REQUEST) || + ap->ar_hln != ETH_ALEN || + ap->ar_pro != htons(ETH_P_IP) || + ap->ar_pln != 4) + return EBT_CONTINUE; + + shp = skb_header_pointer(skb, sizeof(_ah), ETH_ALEN, &_sha); + if (shp == NULL) + return EBT_DROP; + + siptr = skb_header_pointer(skb, sizeof(_ah) + ETH_ALEN, + sizeof(_sip), &_sip); + if (siptr == NULL) + return EBT_DROP; + + diptr = skb_header_pointer(skb, + sizeof(_ah) + 2 * ETH_ALEN + sizeof(_sip), + sizeof(_dip), &_dip); + if (diptr == NULL) + return EBT_DROP; + + arp_send(ARPOP_REPLY, ETH_P_ARP, *siptr, (struct net_device *)par->in, + *diptr, shp, info->mac, shp); + + return info->target; +} + +static int ebt_arpreply_tg_check(const struct xt_tgchk_param *par) +{ + const struct ebt_arpreply_info *info = par->targinfo; + const struct ebt_entry *e = par->entryinfo; + + if (BASE_CHAIN && info->target == EBT_RETURN) + return -EINVAL; + if (e->ethproto != htons(ETH_P_ARP) || + e->invflags & EBT_IPROTO) + return -EINVAL; + return 0; +} + +static struct xt_target ebt_arpreply_tg_reg __read_mostly = { + .name = "arpreply", + .revision = 0, + .family = NFPROTO_BRIDGE, + .table = "nat", + .hooks = (1 << NF_BR_NUMHOOKS) | (1 << NF_BR_PRE_ROUTING), + .target = ebt_arpreply_tg, + .checkentry = ebt_arpreply_tg_check, + .targetsize = sizeof(struct ebt_arpreply_info), + .me = THIS_MODULE, +}; + +static int __init ebt_arpreply_init(void) +{ + return xt_register_target(&ebt_arpreply_tg_reg); +} + +static void __exit ebt_arpreply_fini(void) +{ + xt_unregister_target(&ebt_arpreply_tg_reg); +} + +module_init(ebt_arpreply_init); +module_exit(ebt_arpreply_fini); +MODULE_DESCRIPTION("Ebtables: ARP reply target"); +MODULE_LICENSE("GPL"); diff --git a/net/bridge/netfilter/ebt_dnat.c b/net/bridge/netfilter/ebt_dnat.c new file mode 100644 index 00000000..c59f7bfa --- /dev/null +++ b/net/bridge/netfilter/ebt_dnat.c @@ -0,0 +1,74 @@ +/* + * ebt_dnat + * + * Authors: + * Bart De Schuymer <bdschuym@pandora.be> + * + * June, 2002 + * + */ +#include <linux/module.h> +#include <net/sock.h> +#include <linux/netfilter.h> +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter_bridge/ebtables.h> +#include <linux/netfilter_bridge/ebt_nat.h> + +static unsigned int +ebt_dnat_tg(struct sk_buff *skb, const struct xt_action_param *par) +{ + const struct ebt_nat_info *info = par->targinfo; + + if (!skb_make_writable(skb, 0)) + return EBT_DROP; + + memcpy(eth_hdr(skb)->h_dest, info->mac, ETH_ALEN); + return info->target; +} + +static int ebt_dnat_tg_check(const struct xt_tgchk_param *par) +{ + const struct ebt_nat_info *info = par->targinfo; + unsigned int hook_mask; + + if (BASE_CHAIN && info->target == EBT_RETURN) + return -EINVAL; + + hook_mask = par->hook_mask & ~(1 << NF_BR_NUMHOOKS); + if ((strcmp(par->table, "nat") != 0 || + (hook_mask & ~((1 << NF_BR_PRE_ROUTING) | + (1 << NF_BR_LOCAL_OUT)))) && + (strcmp(par->table, "broute") != 0 || + hook_mask & ~(1 << NF_BR_BROUTING))) + return -EINVAL; + if (INVALID_TARGET) + return -EINVAL; + return 0; +} + +static struct xt_target ebt_dnat_tg_reg __read_mostly = { + .name = "dnat", + .revision = 0, + .family = NFPROTO_BRIDGE, + .hooks = (1 << NF_BR_NUMHOOKS) | (1 << NF_BR_PRE_ROUTING) | + (1 << NF_BR_LOCAL_OUT) | (1 << NF_BR_BROUTING), + .target = ebt_dnat_tg, + .checkentry = ebt_dnat_tg_check, + .targetsize = sizeof(struct ebt_nat_info), + .me = THIS_MODULE, +}; + +static int __init ebt_dnat_init(void) +{ + return xt_register_target(&ebt_dnat_tg_reg); +} + +static void __exit ebt_dnat_fini(void) +{ + xt_unregister_target(&ebt_dnat_tg_reg); +} + +module_init(ebt_dnat_init); +module_exit(ebt_dnat_fini); +MODULE_DESCRIPTION("Ebtables: Destination MAC address translation"); +MODULE_LICENSE("GPL"); diff --git a/net/bridge/netfilter/ebt_ip.c b/net/bridge/netfilter/ebt_ip.c new file mode 100644 index 00000000..23bca62d --- /dev/null +++ b/net/bridge/netfilter/ebt_ip.c @@ -0,0 +1,130 @@ +/* + * ebt_ip + * + * Authors: + * Bart De Schuymer <bdschuym@pandora.be> + * + * April, 2002 + * + * Changes: + * added ip-sport and ip-dport + * Innominate Security Technologies AG <mhopf@innominate.com> + * September, 2002 + */ +#include <linux/ip.h> +#include <net/ip.h> +#include <linux/in.h> +#include <linux/module.h> +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter_bridge/ebtables.h> +#include <linux/netfilter_bridge/ebt_ip.h> + +struct tcpudphdr { + __be16 src; + __be16 dst; +}; + +static bool +ebt_ip_mt(const struct sk_buff *skb, struct xt_action_param *par) +{ + const struct ebt_ip_info *info = par->matchinfo; + const struct iphdr *ih; + struct iphdr _iph; + const struct tcpudphdr *pptr; + struct tcpudphdr _ports; + + ih = skb_header_pointer(skb, 0, sizeof(_iph), &_iph); + if (ih == NULL) + return false; + if (info->bitmask & EBT_IP_TOS && + FWINV(info->tos != ih->tos, EBT_IP_TOS)) + return false; + if (info->bitmask & EBT_IP_SOURCE && + FWINV((ih->saddr & info->smsk) != + info->saddr, EBT_IP_SOURCE)) + return false; + if ((info->bitmask & EBT_IP_DEST) && + FWINV((ih->daddr & info->dmsk) != + info->daddr, EBT_IP_DEST)) + return false; + if (info->bitmask & EBT_IP_PROTO) { + if (FWINV(info->protocol != ih->protocol, EBT_IP_PROTO)) + return false; + if (!(info->bitmask & EBT_IP_DPORT) && + !(info->bitmask & EBT_IP_SPORT)) + return true; + if (ntohs(ih->frag_off) & IP_OFFSET) + return false; + pptr = skb_header_pointer(skb, ih->ihl*4, + sizeof(_ports), &_ports); + if (pptr == NULL) + return false; + if (info->bitmask & EBT_IP_DPORT) { + u32 dst = ntohs(pptr->dst); + if (FWINV(dst < info->dport[0] || + dst > info->dport[1], + EBT_IP_DPORT)) + return false; + } + if (info->bitmask & EBT_IP_SPORT) { + u32 src = ntohs(pptr->src); + if (FWINV(src < info->sport[0] || + src > info->sport[1], + EBT_IP_SPORT)) + return false; + } + } + return true; +} + +static int ebt_ip_mt_check(const struct xt_mtchk_param *par) +{ + const struct ebt_ip_info *info = par->matchinfo; + const struct ebt_entry *e = par->entryinfo; + + if (e->ethproto != htons(ETH_P_IP) || + e->invflags & EBT_IPROTO) + return -EINVAL; + if (info->bitmask & ~EBT_IP_MASK || info->invflags & ~EBT_IP_MASK) + return -EINVAL; + if (info->bitmask & (EBT_IP_DPORT | EBT_IP_SPORT)) { + if (info->invflags & EBT_IP_PROTO) + return -EINVAL; + if (info->protocol != IPPROTO_TCP && + info->protocol != IPPROTO_UDP && + info->protocol != IPPROTO_UDPLITE && + info->protocol != IPPROTO_SCTP && + info->protocol != IPPROTO_DCCP) + return -EINVAL; + } + if (info->bitmask & EBT_IP_DPORT && info->dport[0] > info->dport[1]) + return -EINVAL; + if (info->bitmask & EBT_IP_SPORT && info->sport[0] > info->sport[1]) + return -EINVAL; + return 0; +} + +static struct xt_match ebt_ip_mt_reg __read_mostly = { + .name = "ip", + .revision = 0, + .family = NFPROTO_BRIDGE, + .match = ebt_ip_mt, + .checkentry = ebt_ip_mt_check, + .matchsize = sizeof(struct ebt_ip_info), + .me = THIS_MODULE, +}; + +static int __init ebt_ip_init(void) +{ + return xt_register_match(&ebt_ip_mt_reg); +} + +static void __exit ebt_ip_fini(void) +{ + xt_unregister_match(&ebt_ip_mt_reg); +} + +module_init(ebt_ip_init); +module_exit(ebt_ip_fini); +MODULE_DESCRIPTION("Ebtables: IPv4 protocol packet match"); +MODULE_LICENSE("GPL"); diff --git a/net/bridge/netfilter/ebt_ip6.c b/net/bridge/netfilter/ebt_ip6.c new file mode 100644 index 00000000..99c85668 --- /dev/null +++ b/net/bridge/netfilter/ebt_ip6.c @@ -0,0 +1,156 @@ +/* + * ebt_ip6 + * + * Authors: + * Manohar Castelino <manohar.r.castelino@intel.com> + * Kuo-Lang Tseng <kuo-lang.tseng@intel.com> + * Jan Engelhardt <jengelh@medozas.de> + * + * Summary: + * This is just a modification of the IPv4 code written by + * Bart De Schuymer <bdschuym@pandora.be> + * with the changes required to support IPv6 + * + * Jan, 2008 + */ +#include <linux/ipv6.h> +#include <net/ipv6.h> +#include <linux/in.h> +#include <linux/module.h> +#include <net/dsfield.h> +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter_bridge/ebtables.h> +#include <linux/netfilter_bridge/ebt_ip6.h> + +union pkthdr { + struct { + __be16 src; + __be16 dst; + } tcpudphdr; + struct { + u8 type; + u8 code; + } icmphdr; +}; + +static bool +ebt_ip6_mt(const struct sk_buff *skb, struct xt_action_param *par) +{ + const struct ebt_ip6_info *info = par->matchinfo; + const struct ipv6hdr *ih6; + struct ipv6hdr _ip6h; + const union pkthdr *pptr; + union pkthdr _pkthdr; + + ih6 = skb_header_pointer(skb, 0, sizeof(_ip6h), &_ip6h); + if (ih6 == NULL) + return false; + if (info->bitmask & EBT_IP6_TCLASS && + FWINV(info->tclass != ipv6_get_dsfield(ih6), EBT_IP6_TCLASS)) + return false; + if (FWINV(ipv6_masked_addr_cmp(&ih6->saddr, &info->smsk, + &info->saddr), EBT_IP6_SOURCE) || + FWINV(ipv6_masked_addr_cmp(&ih6->daddr, &info->dmsk, + &info->daddr), EBT_IP6_DEST)) + return false; + if (info->bitmask & EBT_IP6_PROTO) { + uint8_t nexthdr = ih6->nexthdr; + __be16 frag_off; + int offset_ph; + + offset_ph = ipv6_skip_exthdr(skb, sizeof(_ip6h), &nexthdr, &frag_off); + if (offset_ph == -1) + return false; + if (FWINV(info->protocol != nexthdr, EBT_IP6_PROTO)) + return false; + if (!(info->bitmask & ( EBT_IP6_DPORT | + EBT_IP6_SPORT | EBT_IP6_ICMP6))) + return true; + + /* min icmpv6 headersize is 4, so sizeof(_pkthdr) is ok. */ + pptr = skb_header_pointer(skb, offset_ph, sizeof(_pkthdr), + &_pkthdr); + if (pptr == NULL) + return false; + if (info->bitmask & EBT_IP6_DPORT) { + u16 dst = ntohs(pptr->tcpudphdr.dst); + if (FWINV(dst < info->dport[0] || + dst > info->dport[1], EBT_IP6_DPORT)) + return false; + } + if (info->bitmask & EBT_IP6_SPORT) { + u16 src = ntohs(pptr->tcpudphdr.src); + if (FWINV(src < info->sport[0] || + src > info->sport[1], EBT_IP6_SPORT)) + return false; + } + if ((info->bitmask & EBT_IP6_ICMP6) && + FWINV(pptr->icmphdr.type < info->icmpv6_type[0] || + pptr->icmphdr.type > info->icmpv6_type[1] || + pptr->icmphdr.code < info->icmpv6_code[0] || + pptr->icmphdr.code > info->icmpv6_code[1], + EBT_IP6_ICMP6)) + return false; + } + return true; +} + +static int ebt_ip6_mt_check(const struct xt_mtchk_param *par) +{ + const struct ebt_entry *e = par->entryinfo; + struct ebt_ip6_info *info = par->matchinfo; + + if (e->ethproto != htons(ETH_P_IPV6) || e->invflags & EBT_IPROTO) + return -EINVAL; + if (info->bitmask & ~EBT_IP6_MASK || info->invflags & ~EBT_IP6_MASK) + return -EINVAL; + if (info->bitmask & (EBT_IP6_DPORT | EBT_IP6_SPORT)) { + if (info->invflags & EBT_IP6_PROTO) + return -EINVAL; + if (info->protocol != IPPROTO_TCP && + info->protocol != IPPROTO_UDP && + info->protocol != IPPROTO_UDPLITE && + info->protocol != IPPROTO_SCTP && + info->protocol != IPPROTO_DCCP) + return -EINVAL; + } + if (info->bitmask & EBT_IP6_DPORT && info->dport[0] > info->dport[1]) + return -EINVAL; + if (info->bitmask & EBT_IP6_SPORT && info->sport[0] > info->sport[1]) + return -EINVAL; + if (info->bitmask & EBT_IP6_ICMP6) { + if ((info->invflags & EBT_IP6_PROTO) || + info->protocol != IPPROTO_ICMPV6) + return -EINVAL; + if (info->icmpv6_type[0] > info->icmpv6_type[1] || + info->icmpv6_code[0] > info->icmpv6_code[1]) + return -EINVAL; + } + return 0; +} + +static struct xt_match ebt_ip6_mt_reg __read_mostly = { + .name = "ip6", + .revision = 0, + .family = NFPROTO_BRIDGE, + .match = ebt_ip6_mt, + .checkentry = ebt_ip6_mt_check, + .matchsize = sizeof(struct ebt_ip6_info), + .me = THIS_MODULE, +}; + +static int __init ebt_ip6_init(void) +{ + return xt_register_match(&ebt_ip6_mt_reg); +} + +static void __exit ebt_ip6_fini(void) +{ + xt_unregister_match(&ebt_ip6_mt_reg); +} + +module_init(ebt_ip6_init); +module_exit(ebt_ip6_fini); +MODULE_DESCRIPTION("Ebtables: IPv6 protocol packet match"); +MODULE_AUTHOR("Kuo-Lang Tseng <kuo-lang.tseng@intel.com>"); +MODULE_LICENSE("GPL"); diff --git a/net/bridge/netfilter/ebt_limit.c b/net/bridge/netfilter/ebt_limit.c new file mode 100644 index 00000000..517e78be --- /dev/null +++ b/net/bridge/netfilter/ebt_limit.c @@ -0,0 +1,127 @@ +/* + * ebt_limit + * + * Authors: + * Tom Marshall <tommy@home.tig-grr.com> + * + * Mostly copied from netfilter's ipt_limit.c, see that file for + * more explanation + * + * September, 2003 + * + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#include <linux/module.h> +#include <linux/netdevice.h> +#include <linux/spinlock.h> +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter_bridge/ebtables.h> +#include <linux/netfilter_bridge/ebt_limit.h> + +static DEFINE_SPINLOCK(limit_lock); + +#define MAX_CPJ (0xFFFFFFFF / (HZ*60*60*24)) + +#define _POW2_BELOW2(x) ((x)|((x)>>1)) +#define _POW2_BELOW4(x) (_POW2_BELOW2(x)|_POW2_BELOW2((x)>>2)) +#define _POW2_BELOW8(x) (_POW2_BELOW4(x)|_POW2_BELOW4((x)>>4)) +#define _POW2_BELOW16(x) (_POW2_BELOW8(x)|_POW2_BELOW8((x)>>8)) +#define _POW2_BELOW32(x) (_POW2_BELOW16(x)|_POW2_BELOW16((x)>>16)) +#define POW2_BELOW32(x) ((_POW2_BELOW32(x)>>1) + 1) + +#define CREDITS_PER_JIFFY POW2_BELOW32(MAX_CPJ) + +static bool +ebt_limit_mt(const struct sk_buff *skb, struct xt_action_param *par) +{ + struct ebt_limit_info *info = (void *)par->matchinfo; + unsigned long now = jiffies; + + spin_lock_bh(&limit_lock); + info->credit += (now - xchg(&info->prev, now)) * CREDITS_PER_JIFFY; + if (info->credit > info->credit_cap) + info->credit = info->credit_cap; + + if (info->credit >= info->cost) { + /* We're not limited. */ + info->credit -= info->cost; + spin_unlock_bh(&limit_lock); + return true; + } + + spin_unlock_bh(&limit_lock); + return false; +} + +/* Precision saver. */ +static u_int32_t +user2credits(u_int32_t user) +{ + /* If multiplying would overflow... */ + if (user > 0xFFFFFFFF / (HZ*CREDITS_PER_JIFFY)) + /* Divide first. */ + return (user / EBT_LIMIT_SCALE) * HZ * CREDITS_PER_JIFFY; + + return (user * HZ * CREDITS_PER_JIFFY) / EBT_LIMIT_SCALE; +} + +static int ebt_limit_mt_check(const struct xt_mtchk_param *par) +{ + struct ebt_limit_info *info = par->matchinfo; + + /* Check for overflow. */ + if (info->burst == 0 || + user2credits(info->avg * info->burst) < user2credits(info->avg)) { + pr_info("overflow, try lower: %u/%u\n", + info->avg, info->burst); + return -EINVAL; + } + + /* User avg in seconds * EBT_LIMIT_SCALE: convert to jiffies * 128. */ + info->prev = jiffies; + info->credit = user2credits(info->avg * info->burst); + info->credit_cap = user2credits(info->avg * info->burst); + info->cost = user2credits(info->avg); + return 0; +} + + +#ifdef CONFIG_COMPAT +/* + * no conversion function needed -- + * only avg/burst have meaningful values in userspace. + */ +struct ebt_compat_limit_info { + compat_uint_t avg, burst; + compat_ulong_t prev; + compat_uint_t credit, credit_cap, cost; +}; +#endif + +static struct xt_match ebt_limit_mt_reg __read_mostly = { + .name = "limit", + .revision = 0, + .family = NFPROTO_BRIDGE, + .match = ebt_limit_mt, + .checkentry = ebt_limit_mt_check, + .matchsize = sizeof(struct ebt_limit_info), +#ifdef CONFIG_COMPAT + .compatsize = sizeof(struct ebt_compat_limit_info), +#endif + .me = THIS_MODULE, +}; + +static int __init ebt_limit_init(void) +{ + return xt_register_match(&ebt_limit_mt_reg); +} + +static void __exit ebt_limit_fini(void) +{ + xt_unregister_match(&ebt_limit_mt_reg); +} + +module_init(ebt_limit_init); +module_exit(ebt_limit_fini); +MODULE_DESCRIPTION("Ebtables: Rate-limit match"); +MODULE_LICENSE("GPL"); diff --git a/net/bridge/netfilter/ebt_log.c b/net/bridge/netfilter/ebt_log.c new file mode 100644 index 00000000..f88ee537 --- /dev/null +++ b/net/bridge/netfilter/ebt_log.c @@ -0,0 +1,229 @@ +/* + * ebt_log + * + * Authors: + * Bart De Schuymer <bdschuym@pandora.be> + * Harald Welte <laforge@netfilter.org> + * + * April, 2002 + * + */ +#include <linux/module.h> +#include <linux/ip.h> +#include <linux/in.h> +#include <linux/if_arp.h> +#include <linux/spinlock.h> +#include <net/netfilter/nf_log.h> +#include <linux/ipv6.h> +#include <net/ipv6.h> +#include <linux/in6.h> +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter_bridge/ebtables.h> +#include <linux/netfilter_bridge/ebt_log.h> +#include <linux/netfilter.h> + +static DEFINE_SPINLOCK(ebt_log_lock); + +static int ebt_log_tg_check(const struct xt_tgchk_param *par) +{ + struct ebt_log_info *info = par->targinfo; + + if (info->bitmask & ~EBT_LOG_MASK) + return -EINVAL; + if (info->loglevel >= 8) + return -EINVAL; + info->prefix[EBT_LOG_PREFIX_SIZE - 1] = '\0'; + return 0; +} + +struct tcpudphdr +{ + __be16 src; + __be16 dst; +}; + +struct arppayload +{ + unsigned char mac_src[ETH_ALEN]; + unsigned char ip_src[4]; + unsigned char mac_dst[ETH_ALEN]; + unsigned char ip_dst[4]; +}; + +static void +print_ports(const struct sk_buff *skb, uint8_t protocol, int offset) +{ + if (protocol == IPPROTO_TCP || + protocol == IPPROTO_UDP || + protocol == IPPROTO_UDPLITE || + protocol == IPPROTO_SCTP || + protocol == IPPROTO_DCCP) { + const struct tcpudphdr *pptr; + struct tcpudphdr _ports; + + pptr = skb_header_pointer(skb, offset, + sizeof(_ports), &_ports); + if (pptr == NULL) { + printk(" INCOMPLETE TCP/UDP header"); + return; + } + printk(" SPT=%u DPT=%u", ntohs(pptr->src), ntohs(pptr->dst)); + } +} + +static void +ebt_log_packet(u_int8_t pf, unsigned int hooknum, + const struct sk_buff *skb, const struct net_device *in, + const struct net_device *out, const struct nf_loginfo *loginfo, + const char *prefix) +{ + unsigned int bitmask; + + spin_lock_bh(&ebt_log_lock); + printk("<%c>%s IN=%s OUT=%s MAC source = %pM MAC dest = %pM proto = 0x%04x", + '0' + loginfo->u.log.level, prefix, + in ? in->name : "", out ? out->name : "", + eth_hdr(skb)->h_source, eth_hdr(skb)->h_dest, + ntohs(eth_hdr(skb)->h_proto)); + + if (loginfo->type == NF_LOG_TYPE_LOG) + bitmask = loginfo->u.log.logflags; + else + bitmask = NF_LOG_MASK; + + if ((bitmask & EBT_LOG_IP) && eth_hdr(skb)->h_proto == + htons(ETH_P_IP)){ + const struct iphdr *ih; + struct iphdr _iph; + + ih = skb_header_pointer(skb, 0, sizeof(_iph), &_iph); + if (ih == NULL) { + printk(" INCOMPLETE IP header"); + goto out; + } + printk(" IP SRC=%pI4 IP DST=%pI4, IP tos=0x%02X, IP proto=%d", + &ih->saddr, &ih->daddr, ih->tos, ih->protocol); + print_ports(skb, ih->protocol, ih->ihl*4); + goto out; + } + +#if IS_ENABLED(CONFIG_BRIDGE_EBT_IP6) + if ((bitmask & EBT_LOG_IP6) && eth_hdr(skb)->h_proto == + htons(ETH_P_IPV6)) { + const struct ipv6hdr *ih; + struct ipv6hdr _iph; + uint8_t nexthdr; + __be16 frag_off; + int offset_ph; + + ih = skb_header_pointer(skb, 0, sizeof(_iph), &_iph); + if (ih == NULL) { + printk(" INCOMPLETE IPv6 header"); + goto out; + } + printk(" IPv6 SRC=%pI6 IPv6 DST=%pI6, IPv6 priority=0x%01X, Next Header=%d", + &ih->saddr, &ih->daddr, ih->priority, ih->nexthdr); + nexthdr = ih->nexthdr; + offset_ph = ipv6_skip_exthdr(skb, sizeof(_iph), &nexthdr, &frag_off); + if (offset_ph == -1) + goto out; + print_ports(skb, nexthdr, offset_ph); + goto out; + } +#endif + + if ((bitmask & EBT_LOG_ARP) && + ((eth_hdr(skb)->h_proto == htons(ETH_P_ARP)) || + (eth_hdr(skb)->h_proto == htons(ETH_P_RARP)))) { + const struct arphdr *ah; + struct arphdr _arph; + + ah = skb_header_pointer(skb, 0, sizeof(_arph), &_arph); + if (ah == NULL) { + printk(" INCOMPLETE ARP header"); + goto out; + } + printk(" ARP HTYPE=%d, PTYPE=0x%04x, OPCODE=%d", + ntohs(ah->ar_hrd), ntohs(ah->ar_pro), + ntohs(ah->ar_op)); + + /* If it's for Ethernet and the lengths are OK, + * then log the ARP payload */ + if (ah->ar_hrd == htons(1) && + ah->ar_hln == ETH_ALEN && + ah->ar_pln == sizeof(__be32)) { + const struct arppayload *ap; + struct arppayload _arpp; + + ap = skb_header_pointer(skb, sizeof(_arph), + sizeof(_arpp), &_arpp); + if (ap == NULL) { + printk(" INCOMPLETE ARP payload"); + goto out; + } + printk(" ARP MAC SRC=%pM ARP IP SRC=%pI4 ARP MAC DST=%pM ARP IP DST=%pI4", + ap->mac_src, ap->ip_src, ap->mac_dst, ap->ip_dst); + } + } +out: + printk("\n"); + spin_unlock_bh(&ebt_log_lock); + +} + +static unsigned int +ebt_log_tg(struct sk_buff *skb, const struct xt_action_param *par) +{ + const struct ebt_log_info *info = par->targinfo; + struct nf_loginfo li; + + li.type = NF_LOG_TYPE_LOG; + li.u.log.level = info->loglevel; + li.u.log.logflags = info->bitmask; + + if (info->bitmask & EBT_LOG_NFLOG) + nf_log_packet(NFPROTO_BRIDGE, par->hooknum, skb, par->in, + par->out, &li, "%s", info->prefix); + else + ebt_log_packet(NFPROTO_BRIDGE, par->hooknum, skb, par->in, + par->out, &li, info->prefix); + return EBT_CONTINUE; +} + +static struct xt_target ebt_log_tg_reg __read_mostly = { + .name = "log", + .revision = 0, + .family = NFPROTO_BRIDGE, + .target = ebt_log_tg, + .checkentry = ebt_log_tg_check, + .targetsize = sizeof(struct ebt_log_info), + .me = THIS_MODULE, +}; + +static struct nf_logger ebt_log_logger __read_mostly = { + .name = "ebt_log", + .logfn = &ebt_log_packet, + .me = THIS_MODULE, +}; + +static int __init ebt_log_init(void) +{ + int ret; + + ret = xt_register_target(&ebt_log_tg_reg); + if (ret < 0) + return ret; + nf_log_register(NFPROTO_BRIDGE, &ebt_log_logger); + return 0; +} + +static void __exit ebt_log_fini(void) +{ + nf_log_unregister(&ebt_log_logger); + xt_unregister_target(&ebt_log_tg_reg); +} + +module_init(ebt_log_init); +module_exit(ebt_log_fini); +MODULE_DESCRIPTION("Ebtables: Packet logging to syslog"); +MODULE_LICENSE("GPL"); diff --git a/net/bridge/netfilter/ebt_mark.c b/net/bridge/netfilter/ebt_mark.c new file mode 100644 index 00000000..66697cbd --- /dev/null +++ b/net/bridge/netfilter/ebt_mark.c @@ -0,0 +1,110 @@ +/* + * ebt_mark + * + * Authors: + * Bart De Schuymer <bdschuym@pandora.be> + * + * July, 2002 + * + */ + +/* The mark target can be used in any chain, + * I believe adding a mangle table just for marking is total overkill. + * Marking a frame doesn't really change anything in the frame anyway. + */ + +#include <linux/module.h> +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter_bridge/ebtables.h> +#include <linux/netfilter_bridge/ebt_mark_t.h> + +static unsigned int +ebt_mark_tg(struct sk_buff *skb, const struct xt_action_param *par) +{ + const struct ebt_mark_t_info *info = par->targinfo; + int action = info->target & -16; + + if (action == MARK_SET_VALUE) + skb->mark = info->mark; + else if (action == MARK_OR_VALUE) + skb->mark |= info->mark; + else if (action == MARK_AND_VALUE) + skb->mark &= info->mark; + else + skb->mark ^= info->mark; + + return info->target | ~EBT_VERDICT_BITS; +} + +static int ebt_mark_tg_check(const struct xt_tgchk_param *par) +{ + const struct ebt_mark_t_info *info = par->targinfo; + int tmp; + + tmp = info->target | ~EBT_VERDICT_BITS; + if (BASE_CHAIN && tmp == EBT_RETURN) + return -EINVAL; + if (tmp < -NUM_STANDARD_TARGETS || tmp >= 0) + return -EINVAL; + tmp = info->target & ~EBT_VERDICT_BITS; + if (tmp != MARK_SET_VALUE && tmp != MARK_OR_VALUE && + tmp != MARK_AND_VALUE && tmp != MARK_XOR_VALUE) + return -EINVAL; + return 0; +} +#ifdef CONFIG_COMPAT +struct compat_ebt_mark_t_info { + compat_ulong_t mark; + compat_uint_t target; +}; + +static void mark_tg_compat_from_user(void *dst, const void *src) +{ + const struct compat_ebt_mark_t_info *user = src; + struct ebt_mark_t_info *kern = dst; + + kern->mark = user->mark; + kern->target = user->target; +} + +static int mark_tg_compat_to_user(void __user *dst, const void *src) +{ + struct compat_ebt_mark_t_info __user *user = dst; + const struct ebt_mark_t_info *kern = src; + + if (put_user(kern->mark, &user->mark) || + put_user(kern->target, &user->target)) + return -EFAULT; + return 0; +} +#endif + +static struct xt_target ebt_mark_tg_reg __read_mostly = { + .name = "mark", + .revision = 0, + .family = NFPROTO_BRIDGE, + .target = ebt_mark_tg, + .checkentry = ebt_mark_tg_check, + .targetsize = sizeof(struct ebt_mark_t_info), +#ifdef CONFIG_COMPAT + .compatsize = sizeof(struct compat_ebt_mark_t_info), + .compat_from_user = mark_tg_compat_from_user, + .compat_to_user = mark_tg_compat_to_user, +#endif + .me = THIS_MODULE, +}; + +static int __init ebt_mark_init(void) +{ + return xt_register_target(&ebt_mark_tg_reg); +} + +static void __exit ebt_mark_fini(void) +{ + xt_unregister_target(&ebt_mark_tg_reg); +} + +module_init(ebt_mark_init); +module_exit(ebt_mark_fini); +MODULE_DESCRIPTION("Ebtables: Packet mark modification"); +MODULE_LICENSE("GPL"); diff --git a/net/bridge/netfilter/ebt_mark_m.c b/net/bridge/netfilter/ebt_mark_m.c new file mode 100644 index 00000000..d98baefc --- /dev/null +++ b/net/bridge/netfilter/ebt_mark_m.c @@ -0,0 +1,98 @@ +/* + * ebt_mark_m + * + * Authors: + * Bart De Schuymer <bdschuym@pandora.be> + * + * July, 2002 + * + */ +#include <linux/module.h> +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter_bridge/ebtables.h> +#include <linux/netfilter_bridge/ebt_mark_m.h> + +static bool +ebt_mark_mt(const struct sk_buff *skb, struct xt_action_param *par) +{ + const struct ebt_mark_m_info *info = par->matchinfo; + + if (info->bitmask & EBT_MARK_OR) + return !!(skb->mark & info->mask) ^ info->invert; + return ((skb->mark & info->mask) == info->mark) ^ info->invert; +} + +static int ebt_mark_mt_check(const struct xt_mtchk_param *par) +{ + const struct ebt_mark_m_info *info = par->matchinfo; + + if (info->bitmask & ~EBT_MARK_MASK) + return -EINVAL; + if ((info->bitmask & EBT_MARK_OR) && (info->bitmask & EBT_MARK_AND)) + return -EINVAL; + if (!info->bitmask) + return -EINVAL; + return 0; +} + + +#ifdef CONFIG_COMPAT +struct compat_ebt_mark_m_info { + compat_ulong_t mark, mask; + uint8_t invert, bitmask; +}; + +static void mark_mt_compat_from_user(void *dst, const void *src) +{ + const struct compat_ebt_mark_m_info *user = src; + struct ebt_mark_m_info *kern = dst; + + kern->mark = user->mark; + kern->mask = user->mask; + kern->invert = user->invert; + kern->bitmask = user->bitmask; +} + +static int mark_mt_compat_to_user(void __user *dst, const void *src) +{ + struct compat_ebt_mark_m_info __user *user = dst; + const struct ebt_mark_m_info *kern = src; + + if (put_user(kern->mark, &user->mark) || + put_user(kern->mask, &user->mask) || + put_user(kern->invert, &user->invert) || + put_user(kern->bitmask, &user->bitmask)) + return -EFAULT; + return 0; +} +#endif + +static struct xt_match ebt_mark_mt_reg __read_mostly = { + .name = "mark_m", + .revision = 0, + .family = NFPROTO_BRIDGE, + .match = ebt_mark_mt, + .checkentry = ebt_mark_mt_check, + .matchsize = sizeof(struct ebt_mark_m_info), +#ifdef CONFIG_COMPAT + .compatsize = sizeof(struct compat_ebt_mark_m_info), + .compat_from_user = mark_mt_compat_from_user, + .compat_to_user = mark_mt_compat_to_user, +#endif + .me = THIS_MODULE, +}; + +static int __init ebt_mark_m_init(void) +{ + return xt_register_match(&ebt_mark_mt_reg); +} + +static void __exit ebt_mark_m_fini(void) +{ + xt_unregister_match(&ebt_mark_mt_reg); +} + +module_init(ebt_mark_m_init); +module_exit(ebt_mark_m_fini); +MODULE_DESCRIPTION("Ebtables: Packet mark match"); +MODULE_LICENSE("GPL"); diff --git a/net/bridge/netfilter/ebt_nflog.c b/net/bridge/netfilter/ebt_nflog.c new file mode 100644 index 00000000..5be68bbc --- /dev/null +++ b/net/bridge/netfilter/ebt_nflog.c @@ -0,0 +1,72 @@ +/* + * ebt_nflog + * + * Author: + * Peter Warasin <peter@endian.com> + * + * February, 2008 + * + * Based on: + * xt_NFLOG.c, (C) 2006 by Patrick McHardy <kaber@trash.net> + * ebt_ulog.c, (C) 2004 by Bart De Schuymer <bdschuym@pandora.be> + * + */ + +#include <linux/module.h> +#include <linux/spinlock.h> +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter_bridge/ebtables.h> +#include <linux/netfilter_bridge/ebt_nflog.h> +#include <net/netfilter/nf_log.h> + +static unsigned int +ebt_nflog_tg(struct sk_buff *skb, const struct xt_action_param *par) +{ + const struct ebt_nflog_info *info = par->targinfo; + struct nf_loginfo li; + + li.type = NF_LOG_TYPE_ULOG; + li.u.ulog.copy_len = info->len; + li.u.ulog.group = info->group; + li.u.ulog.qthreshold = info->threshold; + + nf_log_packet(PF_BRIDGE, par->hooknum, skb, par->in, par->out, + &li, "%s", info->prefix); + return EBT_CONTINUE; +} + +static int ebt_nflog_tg_check(const struct xt_tgchk_param *par) +{ + struct ebt_nflog_info *info = par->targinfo; + + if (info->flags & ~EBT_NFLOG_MASK) + return -EINVAL; + info->prefix[EBT_NFLOG_PREFIX_SIZE - 1] = '\0'; + return 0; +} + +static struct xt_target ebt_nflog_tg_reg __read_mostly = { + .name = "nflog", + .revision = 0, + .family = NFPROTO_BRIDGE, + .target = ebt_nflog_tg, + .checkentry = ebt_nflog_tg_check, + .targetsize = sizeof(struct ebt_nflog_info), + .me = THIS_MODULE, +}; + +static int __init ebt_nflog_init(void) +{ + return xt_register_target(&ebt_nflog_tg_reg); +} + +static void __exit ebt_nflog_fini(void) +{ + xt_unregister_target(&ebt_nflog_tg_reg); +} + +module_init(ebt_nflog_init); +module_exit(ebt_nflog_fini); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Peter Warasin <peter@endian.com>"); +MODULE_DESCRIPTION("ebtables NFLOG netfilter logging module"); diff --git a/net/bridge/netfilter/ebt_pkttype.c b/net/bridge/netfilter/ebt_pkttype.c new file mode 100644 index 00000000..496a5651 --- /dev/null +++ b/net/bridge/netfilter/ebt_pkttype.c @@ -0,0 +1,56 @@ +/* + * ebt_pkttype + * + * Authors: + * Bart De Schuymer <bdschuym@pandora.be> + * + * April, 2003 + * + */ +#include <linux/module.h> +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter_bridge/ebtables.h> +#include <linux/netfilter_bridge/ebt_pkttype.h> + +static bool +ebt_pkttype_mt(const struct sk_buff *skb, struct xt_action_param *par) +{ + const struct ebt_pkttype_info *info = par->matchinfo; + + return (skb->pkt_type == info->pkt_type) ^ info->invert; +} + +static int ebt_pkttype_mt_check(const struct xt_mtchk_param *par) +{ + const struct ebt_pkttype_info *info = par->matchinfo; + + if (info->invert != 0 && info->invert != 1) + return -EINVAL; + /* Allow any pkt_type value */ + return 0; +} + +static struct xt_match ebt_pkttype_mt_reg __read_mostly = { + .name = "pkttype", + .revision = 0, + .family = NFPROTO_BRIDGE, + .match = ebt_pkttype_mt, + .checkentry = ebt_pkttype_mt_check, + .matchsize = sizeof(struct ebt_pkttype_info), + .me = THIS_MODULE, +}; + +static int __init ebt_pkttype_init(void) +{ + return xt_register_match(&ebt_pkttype_mt_reg); +} + +static void __exit ebt_pkttype_fini(void) +{ + xt_unregister_match(&ebt_pkttype_mt_reg); +} + +module_init(ebt_pkttype_init); +module_exit(ebt_pkttype_fini); +MODULE_DESCRIPTION("Ebtables: Link layer packet type match"); +MODULE_LICENSE("GPL"); diff --git a/net/bridge/netfilter/ebt_redirect.c b/net/bridge/netfilter/ebt_redirect.c new file mode 100644 index 00000000..46624bb6 --- /dev/null +++ b/net/bridge/netfilter/ebt_redirect.c @@ -0,0 +1,80 @@ +/* + * ebt_redirect + * + * Authors: + * Bart De Schuymer <bdschuym@pandora.be> + * + * April, 2002 + * + */ +#include <linux/module.h> +#include <net/sock.h> +#include "../br_private.h" +#include <linux/netfilter.h> +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter_bridge/ebtables.h> +#include <linux/netfilter_bridge/ebt_redirect.h> + +static unsigned int +ebt_redirect_tg(struct sk_buff *skb, const struct xt_action_param *par) +{ + const struct ebt_redirect_info *info = par->targinfo; + + if (!skb_make_writable(skb, 0)) + return EBT_DROP; + + if (par->hooknum != NF_BR_BROUTING) + /* rcu_read_lock()ed by nf_hook_slow */ + memcpy(eth_hdr(skb)->h_dest, + br_port_get_rcu(par->in)->br->dev->dev_addr, ETH_ALEN); + else + memcpy(eth_hdr(skb)->h_dest, par->in->dev_addr, ETH_ALEN); + skb->pkt_type = PACKET_HOST; + return info->target; +} + +static int ebt_redirect_tg_check(const struct xt_tgchk_param *par) +{ + const struct ebt_redirect_info *info = par->targinfo; + unsigned int hook_mask; + + if (BASE_CHAIN && info->target == EBT_RETURN) + return -EINVAL; + + hook_mask = par->hook_mask & ~(1 << NF_BR_NUMHOOKS); + if ((strcmp(par->table, "nat") != 0 || + hook_mask & ~(1 << NF_BR_PRE_ROUTING)) && + (strcmp(par->table, "broute") != 0 || + hook_mask & ~(1 << NF_BR_BROUTING))) + return -EINVAL; + if (INVALID_TARGET) + return -EINVAL; + return 0; +} + +static struct xt_target ebt_redirect_tg_reg __read_mostly = { + .name = "redirect", + .revision = 0, + .family = NFPROTO_BRIDGE, + .hooks = (1 << NF_BR_NUMHOOKS) | (1 << NF_BR_PRE_ROUTING) | + (1 << NF_BR_BROUTING), + .target = ebt_redirect_tg, + .checkentry = ebt_redirect_tg_check, + .targetsize = sizeof(struct ebt_redirect_info), + .me = THIS_MODULE, +}; + +static int __init ebt_redirect_init(void) +{ + return xt_register_target(&ebt_redirect_tg_reg); +} + +static void __exit ebt_redirect_fini(void) +{ + xt_unregister_target(&ebt_redirect_tg_reg); +} + +module_init(ebt_redirect_init); +module_exit(ebt_redirect_fini); +MODULE_DESCRIPTION("Ebtables: Packet redirection to localhost"); +MODULE_LICENSE("GPL"); diff --git a/net/bridge/netfilter/ebt_snat.c b/net/bridge/netfilter/ebt_snat.c new file mode 100644 index 00000000..f8f0bd1a --- /dev/null +++ b/net/bridge/netfilter/ebt_snat.c @@ -0,0 +1,87 @@ +/* + * ebt_snat + * + * Authors: + * Bart De Schuymer <bdschuym@pandora.be> + * + * June, 2002 + * + */ +#include <linux/module.h> +#include <net/sock.h> +#include <linux/if_arp.h> +#include <net/arp.h> +#include <linux/netfilter.h> +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter_bridge/ebtables.h> +#include <linux/netfilter_bridge/ebt_nat.h> + +static unsigned int +ebt_snat_tg(struct sk_buff *skb, const struct xt_action_param *par) +{ + const struct ebt_nat_info *info = par->targinfo; + + if (!skb_make_writable(skb, 0)) + return EBT_DROP; + + memcpy(eth_hdr(skb)->h_source, info->mac, ETH_ALEN); + if (!(info->target & NAT_ARP_BIT) && + eth_hdr(skb)->h_proto == htons(ETH_P_ARP)) { + const struct arphdr *ap; + struct arphdr _ah; + + ap = skb_header_pointer(skb, 0, sizeof(_ah), &_ah); + if (ap == NULL) + return EBT_DROP; + if (ap->ar_hln != ETH_ALEN) + goto out; + if (skb_store_bits(skb, sizeof(_ah), info->mac,ETH_ALEN)) + return EBT_DROP; + } +out: + return info->target | ~EBT_VERDICT_BITS; +} + +static int ebt_snat_tg_check(const struct xt_tgchk_param *par) +{ + const struct ebt_nat_info *info = par->targinfo; + int tmp; + + tmp = info->target | ~EBT_VERDICT_BITS; + if (BASE_CHAIN && tmp == EBT_RETURN) + return -EINVAL; + + if (tmp < -NUM_STANDARD_TARGETS || tmp >= 0) + return -EINVAL; + tmp = info->target | EBT_VERDICT_BITS; + if ((tmp & ~NAT_ARP_BIT) != ~NAT_ARP_BIT) + return -EINVAL; + return 0; +} + +static struct xt_target ebt_snat_tg_reg __read_mostly = { + .name = "snat", + .revision = 0, + .family = NFPROTO_BRIDGE, + .table = "nat", + .hooks = (1 << NF_BR_NUMHOOKS) | (1 << NF_BR_POST_ROUTING), + .target = ebt_snat_tg, + .checkentry = ebt_snat_tg_check, + .targetsize = sizeof(struct ebt_nat_info), + .me = THIS_MODULE, +}; + +static int __init ebt_snat_init(void) +{ + return xt_register_target(&ebt_snat_tg_reg); +} + +static void __exit ebt_snat_fini(void) +{ + xt_unregister_target(&ebt_snat_tg_reg); +} + +module_init(ebt_snat_init); +module_exit(ebt_snat_fini); +MODULE_DESCRIPTION("Ebtables: Source MAC address translation"); +MODULE_LICENSE("GPL"); diff --git a/net/bridge/netfilter/ebt_stp.c b/net/bridge/netfilter/ebt_stp.c new file mode 100644 index 00000000..5b33a2e6 --- /dev/null +++ b/net/bridge/netfilter/ebt_stp.c @@ -0,0 +1,197 @@ +/* + * ebt_stp + * + * Authors: + * Bart De Schuymer <bdschuym@pandora.be> + * Stephen Hemminger <shemminger@osdl.org> + * + * July, 2003 + */ +#include <linux/etherdevice.h> +#include <linux/module.h> +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter_bridge/ebtables.h> +#include <linux/netfilter_bridge/ebt_stp.h> + +#define BPDU_TYPE_CONFIG 0 +#define BPDU_TYPE_TCN 0x80 + +struct stp_header { + uint8_t dsap; + uint8_t ssap; + uint8_t ctrl; + uint8_t pid; + uint8_t vers; + uint8_t type; +}; + +struct stp_config_pdu { + uint8_t flags; + uint8_t root[8]; + uint8_t root_cost[4]; + uint8_t sender[8]; + uint8_t port[2]; + uint8_t msg_age[2]; + uint8_t max_age[2]; + uint8_t hello_time[2]; + uint8_t forward_delay[2]; +}; + +#define NR16(p) (p[0] << 8 | p[1]) +#define NR32(p) ((p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3]) + +static bool ebt_filter_config(const struct ebt_stp_info *info, + const struct stp_config_pdu *stpc) +{ + const struct ebt_stp_config_info *c; + uint16_t v16; + uint32_t v32; + int verdict, i; + + c = &info->config; + if ((info->bitmask & EBT_STP_FLAGS) && + FWINV(c->flags != stpc->flags, EBT_STP_FLAGS)) + return false; + if (info->bitmask & EBT_STP_ROOTPRIO) { + v16 = NR16(stpc->root); + if (FWINV(v16 < c->root_priol || + v16 > c->root_priou, EBT_STP_ROOTPRIO)) + return false; + } + if (info->bitmask & EBT_STP_ROOTADDR) { + verdict = 0; + for (i = 0; i < 6; i++) + verdict |= (stpc->root[2+i] ^ c->root_addr[i]) & + c->root_addrmsk[i]; + if (FWINV(verdict != 0, EBT_STP_ROOTADDR)) + return false; + } + if (info->bitmask & EBT_STP_ROOTCOST) { + v32 = NR32(stpc->root_cost); + if (FWINV(v32 < c->root_costl || + v32 > c->root_costu, EBT_STP_ROOTCOST)) + return false; + } + if (info->bitmask & EBT_STP_SENDERPRIO) { + v16 = NR16(stpc->sender); + if (FWINV(v16 < c->sender_priol || + v16 > c->sender_priou, EBT_STP_SENDERPRIO)) + return false; + } + if (info->bitmask & EBT_STP_SENDERADDR) { + verdict = 0; + for (i = 0; i < 6; i++) + verdict |= (stpc->sender[2+i] ^ c->sender_addr[i]) & + c->sender_addrmsk[i]; + if (FWINV(verdict != 0, EBT_STP_SENDERADDR)) + return false; + } + if (info->bitmask & EBT_STP_PORT) { + v16 = NR16(stpc->port); + if (FWINV(v16 < c->portl || + v16 > c->portu, EBT_STP_PORT)) + return false; + } + if (info->bitmask & EBT_STP_MSGAGE) { + v16 = NR16(stpc->msg_age); + if (FWINV(v16 < c->msg_agel || + v16 > c->msg_ageu, EBT_STP_MSGAGE)) + return false; + } + if (info->bitmask & EBT_STP_MAXAGE) { + v16 = NR16(stpc->max_age); + if (FWINV(v16 < c->max_agel || + v16 > c->max_ageu, EBT_STP_MAXAGE)) + return false; + } + if (info->bitmask & EBT_STP_HELLOTIME) { + v16 = NR16(stpc->hello_time); + if (FWINV(v16 < c->hello_timel || + v16 > c->hello_timeu, EBT_STP_HELLOTIME)) + return false; + } + if (info->bitmask & EBT_STP_FWDD) { + v16 = NR16(stpc->forward_delay); + if (FWINV(v16 < c->forward_delayl || + v16 > c->forward_delayu, EBT_STP_FWDD)) + return false; + } + return true; +} + +static bool +ebt_stp_mt(const struct sk_buff *skb, struct xt_action_param *par) +{ + const struct ebt_stp_info *info = par->matchinfo; + const struct stp_header *sp; + struct stp_header _stph; + const uint8_t header[6] = {0x42, 0x42, 0x03, 0x00, 0x00, 0x00}; + + sp = skb_header_pointer(skb, 0, sizeof(_stph), &_stph); + if (sp == NULL) + return false; + + /* The stp code only considers these */ + if (memcmp(sp, header, sizeof(header))) + return false; + + if (info->bitmask & EBT_STP_TYPE && + FWINV(info->type != sp->type, EBT_STP_TYPE)) + return false; + + if (sp->type == BPDU_TYPE_CONFIG && + info->bitmask & EBT_STP_CONFIG_MASK) { + const struct stp_config_pdu *st; + struct stp_config_pdu _stpc; + + st = skb_header_pointer(skb, sizeof(_stph), + sizeof(_stpc), &_stpc); + if (st == NULL) + return false; + return ebt_filter_config(info, st); + } + return true; +} + +static int ebt_stp_mt_check(const struct xt_mtchk_param *par) +{ + const struct ebt_stp_info *info = par->matchinfo; + const uint8_t bridge_ula[6] = {0x01, 0x80, 0xc2, 0x00, 0x00, 0x00}; + const uint8_t msk[6] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; + const struct ebt_entry *e = par->entryinfo; + + if (info->bitmask & ~EBT_STP_MASK || info->invflags & ~EBT_STP_MASK || + !(info->bitmask & EBT_STP_MASK)) + return -EINVAL; + /* Make sure the match only receives stp frames */ + if (compare_ether_addr(e->destmac, bridge_ula) || + compare_ether_addr(e->destmsk, msk) || !(e->bitmask & EBT_DESTMAC)) + return -EINVAL; + + return 0; +} + +static struct xt_match ebt_stp_mt_reg __read_mostly = { + .name = "stp", + .revision = 0, + .family = NFPROTO_BRIDGE, + .match = ebt_stp_mt, + .checkentry = ebt_stp_mt_check, + .matchsize = sizeof(struct ebt_stp_info), + .me = THIS_MODULE, +}; + +static int __init ebt_stp_init(void) +{ + return xt_register_match(&ebt_stp_mt_reg); +} + +static void __exit ebt_stp_fini(void) +{ + xt_unregister_match(&ebt_stp_mt_reg); +} + +module_init(ebt_stp_init); +module_exit(ebt_stp_fini); +MODULE_DESCRIPTION("Ebtables: Spanning Tree Protocol packet match"); +MODULE_LICENSE("GPL"); diff --git a/net/bridge/netfilter/ebt_ulog.c b/net/bridge/netfilter/ebt_ulog.c new file mode 100644 index 00000000..5449294b --- /dev/null +++ b/net/bridge/netfilter/ebt_ulog.c @@ -0,0 +1,340 @@ +/* + * netfilter module for userspace bridged Ethernet frames logging daemons + * + * Authors: + * Bart De Schuymer <bdschuym@pandora.be> + * Harald Welte <laforge@netfilter.org> + * + * November, 2004 + * + * Based on ipt_ULOG.c, which is + * (C) 2000-2002 by Harald Welte <laforge@netfilter.org> + * + * This module accepts two parameters: + * + * nlbufsiz: + * The parameter specifies how big the buffer for each netlink multicast + * group is. e.g. If you say nlbufsiz=8192, up to eight kb of packets will + * get accumulated in the kernel until they are sent to userspace. It is + * NOT possible to allocate more than 128kB, and it is strongly discouraged, + * because atomically allocating 128kB inside the network rx softirq is not + * reliable. Please also keep in mind that this buffer size is allocated for + * each nlgroup you are using, so the total kernel memory usage increases + * by that factor. + * + * flushtimeout: + * Specify, after how many hundredths of a second the queue should be + * flushed even if it is not full yet. + * + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/socket.h> +#include <linux/skbuff.h> +#include <linux/kernel.h> +#include <linux/timer.h> +#include <linux/netlink.h> +#include <linux/netdevice.h> +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter_bridge/ebtables.h> +#include <linux/netfilter_bridge/ebt_ulog.h> +#include <net/netfilter/nf_log.h> +#include <net/sock.h> +#include "../br_private.h" + +static unsigned int nlbufsiz = NLMSG_GOODSIZE; +module_param(nlbufsiz, uint, 0600); +MODULE_PARM_DESC(nlbufsiz, "netlink buffer size (number of bytes) " + "(defaults to 4096)"); + +static unsigned int flushtimeout = 10; +module_param(flushtimeout, uint, 0600); +MODULE_PARM_DESC(flushtimeout, "buffer flush timeout (hundredths ofa second) " + "(defaults to 10)"); + +typedef struct { + unsigned int qlen; /* number of nlmsgs' in the skb */ + struct nlmsghdr *lastnlh; /* netlink header of last msg in skb */ + struct sk_buff *skb; /* the pre-allocated skb */ + struct timer_list timer; /* the timer function */ + spinlock_t lock; /* the per-queue lock */ +} ebt_ulog_buff_t; + +static ebt_ulog_buff_t ulog_buffers[EBT_ULOG_MAXNLGROUPS]; +static struct sock *ebtulognl; + +/* send one ulog_buff_t to userspace */ +static void ulog_send(unsigned int nlgroup) +{ + ebt_ulog_buff_t *ub = &ulog_buffers[nlgroup]; + + if (timer_pending(&ub->timer)) + del_timer(&ub->timer); + + if (!ub->skb) + return; + + /* last nlmsg needs NLMSG_DONE */ + if (ub->qlen > 1) + ub->lastnlh->nlmsg_type = NLMSG_DONE; + + NETLINK_CB(ub->skb).dst_group = nlgroup + 1; + netlink_broadcast(ebtulognl, ub->skb, 0, nlgroup + 1, GFP_ATOMIC); + + ub->qlen = 0; + ub->skb = NULL; +} + +/* timer function to flush queue in flushtimeout time */ +static void ulog_timer(unsigned long data) +{ + spin_lock_bh(&ulog_buffers[data].lock); + if (ulog_buffers[data].skb) + ulog_send(data); + spin_unlock_bh(&ulog_buffers[data].lock); +} + +static struct sk_buff *ulog_alloc_skb(unsigned int size) +{ + struct sk_buff *skb; + unsigned int n; + + n = max(size, nlbufsiz); + skb = alloc_skb(n, GFP_ATOMIC | __GFP_NOWARN); + if (!skb) { + if (n > size) { + /* try to allocate only as much as we need for + * current packet */ + skb = alloc_skb(size, GFP_ATOMIC); + if (!skb) + pr_debug("cannot even allocate buffer of size %ub\n", + size); + } + } + + return skb; +} + +static void ebt_ulog_packet(unsigned int hooknr, const struct sk_buff *skb, + const struct net_device *in, const struct net_device *out, + const struct ebt_ulog_info *uloginfo, const char *prefix) +{ + ebt_ulog_packet_msg_t *pm; + size_t size, copy_len; + struct nlmsghdr *nlh; + unsigned int group = uloginfo->nlgroup; + ebt_ulog_buff_t *ub = &ulog_buffers[group]; + spinlock_t *lock = &ub->lock; + ktime_t kt; + + if ((uloginfo->cprange == 0) || + (uloginfo->cprange > skb->len + ETH_HLEN)) + copy_len = skb->len + ETH_HLEN; + else + copy_len = uloginfo->cprange; + + size = NLMSG_SPACE(sizeof(*pm) + copy_len); + if (size > nlbufsiz) { + pr_debug("Size %Zd needed, but nlbufsiz=%d\n", size, nlbufsiz); + return; + } + + spin_lock_bh(lock); + + if (!ub->skb) { + if (!(ub->skb = ulog_alloc_skb(size))) + goto alloc_failure; + } else if (size > skb_tailroom(ub->skb)) { + ulog_send(group); + + if (!(ub->skb = ulog_alloc_skb(size))) + goto alloc_failure; + } + + nlh = NLMSG_PUT(ub->skb, 0, ub->qlen, 0, + size - NLMSG_ALIGN(sizeof(*nlh))); + ub->qlen++; + + pm = NLMSG_DATA(nlh); + + /* Fill in the ulog data */ + pm->version = EBT_ULOG_VERSION; + kt = ktime_get_real(); + pm->stamp = ktime_to_timeval(kt); + if (ub->qlen == 1) + ub->skb->tstamp = kt; + pm->data_len = copy_len; + pm->mark = skb->mark; + pm->hook = hooknr; + if (uloginfo->prefix != NULL) + strcpy(pm->prefix, uloginfo->prefix); + else + *(pm->prefix) = '\0'; + + if (in) { + strcpy(pm->physindev, in->name); + /* If in isn't a bridge, then physindev==indev */ + if (br_port_exists(in)) + /* rcu_read_lock()ed by nf_hook_slow */ + strcpy(pm->indev, br_port_get_rcu(in)->br->dev->name); + else + strcpy(pm->indev, in->name); + } else + pm->indev[0] = pm->physindev[0] = '\0'; + + if (out) { + /* If out exists, then out is a bridge port */ + strcpy(pm->physoutdev, out->name); + /* rcu_read_lock()ed by nf_hook_slow */ + strcpy(pm->outdev, br_port_get_rcu(out)->br->dev->name); + } else + pm->outdev[0] = pm->physoutdev[0] = '\0'; + + if (skb_copy_bits(skb, -ETH_HLEN, pm->data, copy_len) < 0) + BUG(); + + if (ub->qlen > 1) + ub->lastnlh->nlmsg_flags |= NLM_F_MULTI; + + ub->lastnlh = nlh; + + if (ub->qlen >= uloginfo->qthreshold) + ulog_send(group); + else if (!timer_pending(&ub->timer)) { + ub->timer.expires = jiffies + flushtimeout * HZ / 100; + add_timer(&ub->timer); + } + +unlock: + spin_unlock_bh(lock); + + return; + +nlmsg_failure: + pr_debug("error during NLMSG_PUT. This should " + "not happen, please report to author.\n"); +alloc_failure: + goto unlock; +} + +/* this function is registered with the netfilter core */ +static void ebt_log_packet(u_int8_t pf, unsigned int hooknum, + const struct sk_buff *skb, const struct net_device *in, + const struct net_device *out, const struct nf_loginfo *li, + const char *prefix) +{ + struct ebt_ulog_info loginfo; + + if (!li || li->type != NF_LOG_TYPE_ULOG) { + loginfo.nlgroup = EBT_ULOG_DEFAULT_NLGROUP; + loginfo.cprange = 0; + loginfo.qthreshold = EBT_ULOG_DEFAULT_QTHRESHOLD; + loginfo.prefix[0] = '\0'; + } else { + loginfo.nlgroup = li->u.ulog.group; + loginfo.cprange = li->u.ulog.copy_len; + loginfo.qthreshold = li->u.ulog.qthreshold; + strlcpy(loginfo.prefix, prefix, sizeof(loginfo.prefix)); + } + + ebt_ulog_packet(hooknum, skb, in, out, &loginfo, prefix); +} + +static unsigned int +ebt_ulog_tg(struct sk_buff *skb, const struct xt_action_param *par) +{ + ebt_ulog_packet(par->hooknum, skb, par->in, par->out, + par->targinfo, NULL); + return EBT_CONTINUE; +} + +static int ebt_ulog_tg_check(const struct xt_tgchk_param *par) +{ + struct ebt_ulog_info *uloginfo = par->targinfo; + + if (uloginfo->nlgroup > 31) + return -EINVAL; + + uloginfo->prefix[EBT_ULOG_PREFIX_LEN - 1] = '\0'; + + if (uloginfo->qthreshold > EBT_ULOG_MAX_QLEN) + uloginfo->qthreshold = EBT_ULOG_MAX_QLEN; + + return 0; +} + +static struct xt_target ebt_ulog_tg_reg __read_mostly = { + .name = "ulog", + .revision = 0, + .family = NFPROTO_BRIDGE, + .target = ebt_ulog_tg, + .checkentry = ebt_ulog_tg_check, + .targetsize = sizeof(struct ebt_ulog_info), + .me = THIS_MODULE, +}; + +static struct nf_logger ebt_ulog_logger __read_mostly = { + .name = "ebt_ulog", + .logfn = &ebt_log_packet, + .me = THIS_MODULE, +}; + +static int __init ebt_ulog_init(void) +{ + int ret; + int i; + + if (nlbufsiz >= 128*1024) { + pr_warning("Netlink buffer has to be <= 128kB," + " please try a smaller nlbufsiz parameter.\n"); + return -EINVAL; + } + + /* initialize ulog_buffers */ + for (i = 0; i < EBT_ULOG_MAXNLGROUPS; i++) { + setup_timer(&ulog_buffers[i].timer, ulog_timer, i); + spin_lock_init(&ulog_buffers[i].lock); + } + + ebtulognl = netlink_kernel_create(&init_net, NETLINK_NFLOG, + EBT_ULOG_MAXNLGROUPS, NULL, NULL, + THIS_MODULE); + if (!ebtulognl) + ret = -ENOMEM; + else if ((ret = xt_register_target(&ebt_ulog_tg_reg)) != 0) + netlink_kernel_release(ebtulognl); + + if (ret == 0) + nf_log_register(NFPROTO_BRIDGE, &ebt_ulog_logger); + + return ret; +} + +static void __exit ebt_ulog_fini(void) +{ + ebt_ulog_buff_t *ub; + int i; + + nf_log_unregister(&ebt_ulog_logger); + xt_unregister_target(&ebt_ulog_tg_reg); + for (i = 0; i < EBT_ULOG_MAXNLGROUPS; i++) { + ub = &ulog_buffers[i]; + if (timer_pending(&ub->timer)) + del_timer(&ub->timer); + spin_lock_bh(&ub->lock); + if (ub->skb) { + kfree_skb(ub->skb); + ub->skb = NULL; + } + spin_unlock_bh(&ub->lock); + } + netlink_kernel_release(ebtulognl); +} + +module_init(ebt_ulog_init); +module_exit(ebt_ulog_fini); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Bart De Schuymer <bdschuym@pandora.be>"); +MODULE_DESCRIPTION("Ebtables: Packet logging to netlink using ULOG"); diff --git a/net/bridge/netfilter/ebt_vlan.c b/net/bridge/netfilter/ebt_vlan.c new file mode 100644 index 00000000..eae67bf0 --- /dev/null +++ b/net/bridge/netfilter/ebt_vlan.c @@ -0,0 +1,181 @@ +/* + * Description: EBTables 802.1Q match extension kernelspace module. + * Authors: Nick Fedchik <nick@fedchik.org.ua> + * Bart De Schuymer <bdschuym@pandora.be> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/if_ether.h> +#include <linux/if_vlan.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter_bridge/ebtables.h> +#include <linux/netfilter_bridge/ebt_vlan.h> + +#define MODULE_VERS "0.6" + +MODULE_AUTHOR("Nick Fedchik <nick@fedchik.org.ua>"); +MODULE_DESCRIPTION("Ebtables: 802.1Q VLAN tag match"); +MODULE_LICENSE("GPL"); + +#define GET_BITMASK(_BIT_MASK_) info->bitmask & _BIT_MASK_ +#define EXIT_ON_MISMATCH(_MATCH_,_MASK_) {if (!((info->_MATCH_ == _MATCH_)^!!(info->invflags & _MASK_))) return false; } + +static bool +ebt_vlan_mt(const struct sk_buff *skb, struct xt_action_param *par) +{ + const struct ebt_vlan_info *info = par->matchinfo; + + unsigned short TCI; /* Whole TCI, given from parsed frame */ + unsigned short id; /* VLAN ID, given from frame TCI */ + unsigned char prio; /* user_priority, given from frame TCI */ + /* VLAN encapsulated Type/Length field, given from orig frame */ + __be16 encap; + + if (vlan_tx_tag_present(skb)) { + TCI = vlan_tx_tag_get(skb); + encap = skb->protocol; + } else { + const struct vlan_hdr *fp; + struct vlan_hdr _frame; + + fp = skb_header_pointer(skb, 0, sizeof(_frame), &_frame); + if (fp == NULL) + return false; + + TCI = ntohs(fp->h_vlan_TCI); + encap = fp->h_vlan_encapsulated_proto; + } + + /* Tag Control Information (TCI) consists of the following elements: + * - User_priority. The user_priority field is three bits in length, + * interpreted as a binary number. + * - Canonical Format Indicator (CFI). The Canonical Format Indicator + * (CFI) is a single bit flag value. Currently ignored. + * - VLAN Identifier (VID). The VID is encoded as + * an unsigned binary number. */ + id = TCI & VLAN_VID_MASK; + prio = (TCI >> 13) & 0x7; + + /* Checking VLAN Identifier (VID) */ + if (GET_BITMASK(EBT_VLAN_ID)) + EXIT_ON_MISMATCH(id, EBT_VLAN_ID); + + /* Checking user_priority */ + if (GET_BITMASK(EBT_VLAN_PRIO)) + EXIT_ON_MISMATCH(prio, EBT_VLAN_PRIO); + + /* Checking Encapsulated Proto (Length/Type) field */ + if (GET_BITMASK(EBT_VLAN_ENCAP)) + EXIT_ON_MISMATCH(encap, EBT_VLAN_ENCAP); + + return true; +} + +static int ebt_vlan_mt_check(const struct xt_mtchk_param *par) +{ + struct ebt_vlan_info *info = par->matchinfo; + const struct ebt_entry *e = par->entryinfo; + + /* Is it 802.1Q frame checked? */ + if (e->ethproto != htons(ETH_P_8021Q)) { + pr_debug("passed entry proto %2.4X is not 802.1Q (8100)\n", + ntohs(e->ethproto)); + return -EINVAL; + } + + /* Check for bitmask range + * True if even one bit is out of mask */ + if (info->bitmask & ~EBT_VLAN_MASK) { + pr_debug("bitmask %2X is out of mask (%2X)\n", + info->bitmask, EBT_VLAN_MASK); + return -EINVAL; + } + + /* Check for inversion flags range */ + if (info->invflags & ~EBT_VLAN_MASK) { + pr_debug("inversion flags %2X is out of mask (%2X)\n", + info->invflags, EBT_VLAN_MASK); + return -EINVAL; + } + + /* Reserved VLAN ID (VID) values + * ----------------------------- + * 0 - The null VLAN ID. + * 1 - The default Port VID (PVID) + * 0x0FFF - Reserved for implementation use. + * if_vlan.h: VLAN_N_VID 4096. */ + if (GET_BITMASK(EBT_VLAN_ID)) { + if (!!info->id) { /* if id!=0 => check vid range */ + if (info->id > VLAN_N_VID) { + pr_debug("id %d is out of range (1-4096)\n", + info->id); + return -EINVAL; + } + /* Note: This is valid VLAN-tagged frame point. + * Any value of user_priority are acceptable, + * but should be ignored according to 802.1Q Std. + * So we just drop the prio flag. */ + info->bitmask &= ~EBT_VLAN_PRIO; + } + /* Else, id=0 (null VLAN ID) => user_priority range (any?) */ + } + + if (GET_BITMASK(EBT_VLAN_PRIO)) { + if ((unsigned char) info->prio > 7) { + pr_debug("prio %d is out of range (0-7)\n", + info->prio); + return -EINVAL; + } + } + /* Check for encapsulated proto range - it is possible to be + * any value for u_short range. + * if_ether.h: ETH_ZLEN 60 - Min. octets in frame sans FCS */ + if (GET_BITMASK(EBT_VLAN_ENCAP)) { + if ((unsigned short) ntohs(info->encap) < ETH_ZLEN) { + pr_debug("encap frame length %d is less than " + "minimal\n", ntohs(info->encap)); + return -EINVAL; + } + } + + return 0; +} + +static struct xt_match ebt_vlan_mt_reg __read_mostly = { + .name = "vlan", + .revision = 0, + .family = NFPROTO_BRIDGE, + .match = ebt_vlan_mt, + .checkentry = ebt_vlan_mt_check, + .matchsize = sizeof(struct ebt_vlan_info), + .me = THIS_MODULE, +}; + +static int __init ebt_vlan_init(void) +{ + pr_debug("ebtables 802.1Q extension module v" MODULE_VERS "\n"); + return xt_register_match(&ebt_vlan_mt_reg); +} + +static void __exit ebt_vlan_fini(void) +{ + xt_unregister_match(&ebt_vlan_mt_reg); +} + +module_init(ebt_vlan_init); +module_exit(ebt_vlan_fini); diff --git a/net/bridge/netfilter/ebtable_broute.c b/net/bridge/netfilter/ebtable_broute.c new file mode 100644 index 00000000..40d8258b --- /dev/null +++ b/net/bridge/netfilter/ebtable_broute.c @@ -0,0 +1,104 @@ +/* + * ebtable_broute + * + * Authors: + * Bart De Schuymer <bdschuym@pandora.be> + * + * April, 2002 + * + * This table lets you choose between routing and bridging for frames + * entering on a bridge enslaved nic. This table is traversed before any + * other ebtables table. See net/bridge/br_input.c. + */ + +#include <linux/netfilter_bridge/ebtables.h> +#include <linux/module.h> +#include <linux/if_bridge.h> + +/* EBT_ACCEPT means the frame will be bridged + * EBT_DROP means the frame will be routed + */ +static struct ebt_entries initial_chain = { + .name = "BROUTING", + .policy = EBT_ACCEPT, +}; + +static struct ebt_replace_kernel initial_table = +{ + .name = "broute", + .valid_hooks = 1 << NF_BR_BROUTING, + .entries_size = sizeof(struct ebt_entries), + .hook_entry = { + [NF_BR_BROUTING] = &initial_chain, + }, + .entries = (char *)&initial_chain, +}; + +static int check(const struct ebt_table_info *info, unsigned int valid_hooks) +{ + if (valid_hooks & ~(1 << NF_BR_BROUTING)) + return -EINVAL; + return 0; +} + +static const struct ebt_table broute_table = +{ + .name = "broute", + .table = &initial_table, + .valid_hooks = 1 << NF_BR_BROUTING, + .check = check, + .me = THIS_MODULE, +}; + +static int ebt_broute(struct sk_buff *skb) +{ + int ret; + + ret = ebt_do_table(NF_BR_BROUTING, skb, skb->dev, NULL, + dev_net(skb->dev)->xt.broute_table); + if (ret == NF_DROP) + return 1; /* route it */ + return 0; /* bridge it */ +} + +static int __net_init broute_net_init(struct net *net) +{ + net->xt.broute_table = ebt_register_table(net, &broute_table); + if (IS_ERR(net->xt.broute_table)) + return PTR_ERR(net->xt.broute_table); + return 0; +} + +static void __net_exit broute_net_exit(struct net *net) +{ + ebt_unregister_table(net, net->xt.broute_table); +} + +static struct pernet_operations broute_net_ops = { + .init = broute_net_init, + .exit = broute_net_exit, +}; + +static int __init ebtable_broute_init(void) +{ + int ret; + + ret = register_pernet_subsys(&broute_net_ops); + if (ret < 0) + return ret; + /* see br_input.c */ + RCU_INIT_POINTER(br_should_route_hook, + (br_should_route_hook_t *)ebt_broute); + return 0; +} + +static void __exit ebtable_broute_fini(void) +{ + RCU_INIT_POINTER(br_should_route_hook, NULL); + synchronize_net(); + unregister_pernet_subsys(&broute_net_ops); +} + +module_init(ebtable_broute_init); +module_exit(ebtable_broute_fini); +MODULE_LICENSE("GPL"); diff --git a/net/bridge/netfilter/ebtable_filter.c b/net/bridge/netfilter/ebtable_filter.c new file mode 100644 index 00000000..42e6bd09 --- /dev/null +++ b/net/bridge/netfilter/ebtable_filter.c @@ -0,0 +1,139 @@ +/* + * ebtable_filter + * + * Authors: + * Bart De Schuymer <bdschuym@pandora.be> + * + * April, 2002 + * + */ + +#include <linux/netfilter_bridge/ebtables.h> +#include <linux/module.h> + +#define FILTER_VALID_HOOKS ((1 << NF_BR_LOCAL_IN) | (1 << NF_BR_FORWARD) | \ + (1 << NF_BR_LOCAL_OUT)) + +static struct ebt_entries initial_chains[] = +{ + { + .name = "INPUT", + .policy = EBT_ACCEPT, + }, + { + .name = "FORWARD", + .policy = EBT_ACCEPT, + }, + { + .name = "OUTPUT", + .policy = EBT_ACCEPT, + }, +}; + +static struct ebt_replace_kernel initial_table = +{ + .name = "filter", + .valid_hooks = FILTER_VALID_HOOKS, + .entries_size = 3 * sizeof(struct ebt_entries), + .hook_entry = { + [NF_BR_LOCAL_IN] = &initial_chains[0], + [NF_BR_FORWARD] = &initial_chains[1], + [NF_BR_LOCAL_OUT] = &initial_chains[2], + }, + .entries = (char *)initial_chains, +}; + +static int check(const struct ebt_table_info *info, unsigned int valid_hooks) +{ + if (valid_hooks & ~FILTER_VALID_HOOKS) + return -EINVAL; + return 0; +} + +static const struct ebt_table frame_filter = +{ + .name = "filter", + .table = &initial_table, + .valid_hooks = FILTER_VALID_HOOKS, + .check = check, + .me = THIS_MODULE, +}; + +static unsigned int +ebt_in_hook(unsigned int hook, struct sk_buff *skb, const struct net_device *in, + const struct net_device *out, int (*okfn)(struct sk_buff *)) +{ + return ebt_do_table(hook, skb, in, out, dev_net(in)->xt.frame_filter); +} + +static unsigned int +ebt_out_hook(unsigned int hook, struct sk_buff *skb, const struct net_device *in, + const struct net_device *out, int (*okfn)(struct sk_buff *)) +{ + return ebt_do_table(hook, skb, in, out, dev_net(out)->xt.frame_filter); +} + +static struct nf_hook_ops ebt_ops_filter[] __read_mostly = { + { + .hook = ebt_in_hook, + .owner = THIS_MODULE, + .pf = NFPROTO_BRIDGE, + .hooknum = NF_BR_LOCAL_IN, + .priority = NF_BR_PRI_FILTER_BRIDGED, + }, + { + .hook = ebt_in_hook, + .owner = THIS_MODULE, + .pf = NFPROTO_BRIDGE, + .hooknum = NF_BR_FORWARD, + .priority = NF_BR_PRI_FILTER_BRIDGED, + }, + { + .hook = ebt_out_hook, + .owner = THIS_MODULE, + .pf = NFPROTO_BRIDGE, + .hooknum = NF_BR_LOCAL_OUT, + .priority = NF_BR_PRI_FILTER_OTHER, + }, +}; + +static int __net_init frame_filter_net_init(struct net *net) +{ + net->xt.frame_filter = ebt_register_table(net, &frame_filter); + if (IS_ERR(net->xt.frame_filter)) + return PTR_ERR(net->xt.frame_filter); + return 0; +} + +static void __net_exit frame_filter_net_exit(struct net *net) +{ + ebt_unregister_table(net, net->xt.frame_filter); +} + +static struct pernet_operations frame_filter_net_ops = { + .init = frame_filter_net_init, + .exit = frame_filter_net_exit, +}; + +static int __init ebtable_filter_init(void) +{ + int ret; + + ret = register_pernet_subsys(&frame_filter_net_ops); + if (ret < 0) + return ret; + ret = nf_register_hooks(ebt_ops_filter, ARRAY_SIZE(ebt_ops_filter)); + if (ret < 0) + unregister_pernet_subsys(&frame_filter_net_ops); + return ret; +} + +static void __exit ebtable_filter_fini(void) +{ + nf_unregister_hooks(ebt_ops_filter, ARRAY_SIZE(ebt_ops_filter)); + unregister_pernet_subsys(&frame_filter_net_ops); +} + +module_init(ebtable_filter_init); +module_exit(ebtable_filter_fini); +MODULE_LICENSE("GPL"); diff --git a/net/bridge/netfilter/ebtable_nat.c b/net/bridge/netfilter/ebtable_nat.c new file mode 100644 index 00000000..6dc2f878 --- /dev/null +++ b/net/bridge/netfilter/ebtable_nat.c @@ -0,0 +1,139 @@ +/* + * ebtable_nat + * + * Authors: + * Bart De Schuymer <bdschuym@pandora.be> + * + * April, 2002 + * + */ + +#include <linux/netfilter_bridge/ebtables.h> +#include <linux/module.h> + +#define NAT_VALID_HOOKS ((1 << NF_BR_PRE_ROUTING) | (1 << NF_BR_LOCAL_OUT) | \ + (1 << NF_BR_POST_ROUTING)) + +static struct ebt_entries initial_chains[] = +{ + { + .name = "PREROUTING", + .policy = EBT_ACCEPT, + }, + { + .name = "OUTPUT", + .policy = EBT_ACCEPT, + }, + { + .name = "POSTROUTING", + .policy = EBT_ACCEPT, + } +}; + +static struct ebt_replace_kernel initial_table = +{ + .name = "nat", + .valid_hooks = NAT_VALID_HOOKS, + .entries_size = 3 * sizeof(struct ebt_entries), + .hook_entry = { + [NF_BR_PRE_ROUTING] = &initial_chains[0], + [NF_BR_LOCAL_OUT] = &initial_chains[1], + [NF_BR_POST_ROUTING] = &initial_chains[2], + }, + .entries = (char *)initial_chains, +}; + +static int check(const struct ebt_table_info *info, unsigned int valid_hooks) +{ + if (valid_hooks & ~NAT_VALID_HOOKS) + return -EINVAL; + return 0; +} + +static struct ebt_table frame_nat = +{ + .name = "nat", + .table = &initial_table, + .valid_hooks = NAT_VALID_HOOKS, + .check = check, + .me = THIS_MODULE, +}; + +static unsigned int +ebt_nat_in(unsigned int hook, struct sk_buff *skb, const struct net_device *in + , const struct net_device *out, int (*okfn)(struct sk_buff *)) +{ + return ebt_do_table(hook, skb, in, out, dev_net(in)->xt.frame_nat); +} + +static unsigned int +ebt_nat_out(unsigned int hook, struct sk_buff *skb, const struct net_device *in + , const struct net_device *out, int (*okfn)(struct sk_buff *)) +{ + return ebt_do_table(hook, skb, in, out, dev_net(out)->xt.frame_nat); +} + +static struct nf_hook_ops ebt_ops_nat[] __read_mostly = { + { + .hook = ebt_nat_out, + .owner = THIS_MODULE, + .pf = NFPROTO_BRIDGE, + .hooknum = NF_BR_LOCAL_OUT, + .priority = NF_BR_PRI_NAT_DST_OTHER, + }, + { + .hook = ebt_nat_out, + .owner = THIS_MODULE, + .pf = NFPROTO_BRIDGE, + .hooknum = NF_BR_POST_ROUTING, + .priority = NF_BR_PRI_NAT_SRC, + }, + { + .hook = ebt_nat_in, + .owner = THIS_MODULE, + .pf = NFPROTO_BRIDGE, + .hooknum = NF_BR_PRE_ROUTING, + .priority = NF_BR_PRI_NAT_DST_BRIDGED, + }, +}; + +static int __net_init frame_nat_net_init(struct net *net) +{ + net->xt.frame_nat = ebt_register_table(net, &frame_nat); + if (IS_ERR(net->xt.frame_nat)) + return PTR_ERR(net->xt.frame_nat); + return 0; +} + +static void __net_exit frame_nat_net_exit(struct net *net) +{ + ebt_unregister_table(net, net->xt.frame_nat); +} + +static struct pernet_operations frame_nat_net_ops = { + .init = frame_nat_net_init, + .exit = frame_nat_net_exit, +}; + +static int __init ebtable_nat_init(void) +{ + int ret; + + ret = register_pernet_subsys(&frame_nat_net_ops); + if (ret < 0) + return ret; + ret = nf_register_hooks(ebt_ops_nat, ARRAY_SIZE(ebt_ops_nat)); + if (ret < 0) + unregister_pernet_subsys(&frame_nat_net_ops); + return ret; +} + +static void __exit ebtable_nat_fini(void) +{ + nf_unregister_hooks(ebt_ops_nat, ARRAY_SIZE(ebt_ops_nat)); + unregister_pernet_subsys(&frame_nat_net_ops); +} + +module_init(ebtable_nat_init); +module_exit(ebtable_nat_fini); +MODULE_LICENSE("GPL"); diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c new file mode 100644 index 00000000..5fe2ff3b --- /dev/null +++ b/net/bridge/netfilter/ebtables.c @@ -0,0 +1,2421 @@ +/* + * ebtables + * + * Author: + * Bart De Schuymer <bdschuym@pandora.be> + * + * ebtables.c,v 2.0, July, 2002 + * + * This code is stongly inspired on the iptables code which is + * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#include <linux/kmod.h> +#include <linux/module.h> +#include <linux/vmalloc.h> +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter_bridge/ebtables.h> +#include <linux/spinlock.h> +#include <linux/mutex.h> +#include <linux/slab.h> +#include <asm/uaccess.h> +#include <linux/smp.h> +#include <linux/cpumask.h> +#include <net/sock.h> +/* needed for logical [in,out]-dev filtering */ +#include "../br_private.h" + +#define BUGPRINT(format, args...) printk("kernel msg: ebtables bug: please "\ + "report to author: "format, ## args) +/* #define BUGPRINT(format, args...) */ + +/* + * Each cpu has its own set of counters, so there is no need for write_lock in + * the softirq + * For reading or updating the counters, the user context needs to + * get a write_lock + */ + +/* The size of each set of counters is altered to get cache alignment */ +#define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1)) +#define COUNTER_OFFSET(n) (SMP_ALIGN(n * sizeof(struct ebt_counter))) +#define COUNTER_BASE(c, n, cpu) ((struct ebt_counter *)(((char *)c) + \ + COUNTER_OFFSET(n) * cpu)) + + + +static DEFINE_MUTEX(ebt_mutex); + +#ifdef CONFIG_COMPAT +static void ebt_standard_compat_from_user(void *dst, const void *src) +{ + int v = *(compat_int_t *)src; + + if (v >= 0) + v += xt_compat_calc_jump(NFPROTO_BRIDGE, v); + memcpy(dst, &v, sizeof(v)); +} + +static int ebt_standard_compat_to_user(void __user *dst, const void *src) +{ + compat_int_t cv = *(int *)src; + + if (cv >= 0) + cv -= xt_compat_calc_jump(NFPROTO_BRIDGE, cv); + return copy_to_user(dst, &cv, sizeof(cv)) ? -EFAULT : 0; +} +#endif + + +static struct xt_target ebt_standard_target = { + .name = "standard", + .revision = 0, + .family = NFPROTO_BRIDGE, + .targetsize = sizeof(int), +#ifdef CONFIG_COMPAT + .compatsize = sizeof(compat_int_t), + .compat_from_user = ebt_standard_compat_from_user, + .compat_to_user = ebt_standard_compat_to_user, +#endif +}; + +static inline int +ebt_do_watcher(const struct ebt_entry_watcher *w, struct sk_buff *skb, + struct xt_action_param *par) +{ + par->target = w->u.watcher; + par->targinfo = w->data; + w->u.watcher->target(skb, par); + /* watchers don't give a verdict */ + return 0; +} + +static inline int +ebt_do_match(struct ebt_entry_match *m, const struct sk_buff *skb, + struct xt_action_param *par) +{ + par->match = m->u.match; + par->matchinfo = m->data; + return m->u.match->match(skb, par) ? EBT_MATCH : EBT_NOMATCH; +} + +static inline int +ebt_dev_check(const char *entry, const struct net_device *device) +{ + int i = 0; + const char *devname; + + if (*entry == '\0') + return 0; + if (!device) + return 1; + devname = device->name; + /* 1 is the wildcard token */ + while (entry[i] != '\0' && entry[i] != 1 && entry[i] == devname[i]) + i++; + return (devname[i] != entry[i] && entry[i] != 1); +} + +#define FWINV2(bool,invflg) ((bool) ^ !!(e->invflags & invflg)) +/* process standard matches */ +static inline int +ebt_basic_match(const struct ebt_entry *e, const struct sk_buff *skb, + const struct net_device *in, const struct net_device *out) +{ + const struct ethhdr *h = eth_hdr(skb); + const struct net_bridge_port *p; + __be16 ethproto; + int verdict, i; + + if (vlan_tx_tag_present(skb)) + ethproto = htons(ETH_P_8021Q); + else + ethproto = h->h_proto; + + if (e->bitmask & EBT_802_3) { + if (FWINV2(ntohs(ethproto) >= 1536, EBT_IPROTO)) + return 1; + } else if (!(e->bitmask & EBT_NOPROTO) && + FWINV2(e->ethproto != ethproto, EBT_IPROTO)) + return 1; + + if (FWINV2(ebt_dev_check(e->in, in), EBT_IIN)) + return 1; + if (FWINV2(ebt_dev_check(e->out, out), EBT_IOUT)) + return 1; + /* rcu_read_lock()ed by nf_hook_slow */ + if (in && (p = br_port_get_rcu(in)) != NULL && + FWINV2(ebt_dev_check(e->logical_in, p->br->dev), EBT_ILOGICALIN)) + return 1; + if (out && (p = br_port_get_rcu(out)) != NULL && + FWINV2(ebt_dev_check(e->logical_out, p->br->dev), EBT_ILOGICALOUT)) + return 1; + + if (e->bitmask & EBT_SOURCEMAC) { + verdict = 0; + for (i = 0; i < 6; i++) + verdict |= (h->h_source[i] ^ e->sourcemac[i]) & + e->sourcemsk[i]; + if (FWINV2(verdict != 0, EBT_ISOURCE) ) + return 1; + } + if (e->bitmask & EBT_DESTMAC) { + verdict = 0; + for (i = 0; i < 6; i++) + verdict |= (h->h_dest[i] ^ e->destmac[i]) & + e->destmsk[i]; + if (FWINV2(verdict != 0, EBT_IDEST) ) + return 1; + } + return 0; +} + +static inline __pure +struct ebt_entry *ebt_next_entry(const struct ebt_entry *entry) +{ + return (void *)entry + entry->next_offset; +} + +/* Do some firewalling */ +unsigned int ebt_do_table (unsigned int hook, struct sk_buff *skb, + const struct net_device *in, const struct net_device *out, + struct ebt_table *table) +{ + int i, nentries; + struct ebt_entry *point; + struct ebt_counter *counter_base, *cb_base; + const struct ebt_entry_target *t; + int verdict, sp = 0; + struct ebt_chainstack *cs; + struct ebt_entries *chaininfo; + const char *base; + const struct ebt_table_info *private; + struct xt_action_param acpar; + + acpar.family = NFPROTO_BRIDGE; + acpar.in = in; + acpar.out = out; + acpar.hotdrop = false; + acpar.hooknum = hook; + + read_lock_bh(&table->lock); + private = table->private; + cb_base = COUNTER_BASE(private->counters, private->nentries, + smp_processor_id()); + if (private->chainstack) + cs = private->chainstack[smp_processor_id()]; + else + cs = NULL; + chaininfo = private->hook_entry[hook]; + nentries = private->hook_entry[hook]->nentries; + point = (struct ebt_entry *)(private->hook_entry[hook]->data); + counter_base = cb_base + private->hook_entry[hook]->counter_offset; + /* base for chain jumps */ + base = private->entries; + i = 0; + while (i < nentries) { + if (ebt_basic_match(point, skb, in, out)) + goto letscontinue; + + if (EBT_MATCH_ITERATE(point, ebt_do_match, skb, &acpar) != 0) + goto letscontinue; + if (acpar.hotdrop) { + read_unlock_bh(&table->lock); + return NF_DROP; + } + + /* increase counter */ + (*(counter_base + i)).pcnt++; + (*(counter_base + i)).bcnt += skb->len; + + /* these should only watch: not modify, nor tell us + what to do with the packet */ + EBT_WATCHER_ITERATE(point, ebt_do_watcher, skb, &acpar); + + t = (struct ebt_entry_target *) + (((char *)point) + point->target_offset); + /* standard target */ + if (!t->u.target->target) + verdict = ((struct ebt_standard_target *)t)->verdict; + else { + acpar.target = t->u.target; + acpar.targinfo = t->data; + verdict = t->u.target->target(skb, &acpar); + } + if (verdict == EBT_ACCEPT) { + read_unlock_bh(&table->lock); + return NF_ACCEPT; + } + if (verdict == EBT_DROP) { + read_unlock_bh(&table->lock); + return NF_DROP; + } + if (verdict == EBT_RETURN) { +letsreturn: +#ifdef CONFIG_NETFILTER_DEBUG + if (sp == 0) { + BUGPRINT("RETURN on base chain"); + /* act like this is EBT_CONTINUE */ + goto letscontinue; + } +#endif + sp--; + /* put all the local variables right */ + i = cs[sp].n; + chaininfo = cs[sp].chaininfo; + nentries = chaininfo->nentries; + point = cs[sp].e; + counter_base = cb_base + + chaininfo->counter_offset; + continue; + } + if (verdict == EBT_CONTINUE) + goto letscontinue; +#ifdef CONFIG_NETFILTER_DEBUG + if (verdict < 0) { + BUGPRINT("bogus standard verdict\n"); + read_unlock_bh(&table->lock); + return NF_DROP; + } +#endif + /* jump to a udc */ + cs[sp].n = i + 1; + cs[sp].chaininfo = chaininfo; + cs[sp].e = ebt_next_entry(point); + i = 0; + chaininfo = (struct ebt_entries *) (base + verdict); +#ifdef CONFIG_NETFILTER_DEBUG + if (chaininfo->distinguisher) { + BUGPRINT("jump to non-chain\n"); + read_unlock_bh(&table->lock); + return NF_DROP; + } +#endif + nentries = chaininfo->nentries; + point = (struct ebt_entry *)chaininfo->data; + counter_base = cb_base + chaininfo->counter_offset; + sp++; + continue; +letscontinue: + point = ebt_next_entry(point); + i++; + } + + /* I actually like this :) */ + if (chaininfo->policy == EBT_RETURN) + goto letsreturn; + if (chaininfo->policy == EBT_ACCEPT) { + read_unlock_bh(&table->lock); + return NF_ACCEPT; + } + read_unlock_bh(&table->lock); + return NF_DROP; +} + +/* If it succeeds, returns element and locks mutex */ +static inline void * +find_inlist_lock_noload(struct list_head *head, const char *name, int *error, + struct mutex *mutex) +{ + struct { + struct list_head list; + char name[EBT_FUNCTION_MAXNAMELEN]; + } *e; + + *error = mutex_lock_interruptible(mutex); + if (*error != 0) + return NULL; + + list_for_each_entry(e, head, list) { + if (strcmp(e->name, name) == 0) + return e; + } + *error = -ENOENT; + mutex_unlock(mutex); + return NULL; +} + +static void * +find_inlist_lock(struct list_head *head, const char *name, const char *prefix, + int *error, struct mutex *mutex) +{ + return try_then_request_module( + find_inlist_lock_noload(head, name, error, mutex), + "%s%s", prefix, name); +} + +static inline struct ebt_table * +find_table_lock(struct net *net, const char *name, int *error, + struct mutex *mutex) +{ + return find_inlist_lock(&net->xt.tables[NFPROTO_BRIDGE], name, + "ebtable_", error, mutex); +} + +static inline int +ebt_check_match(struct ebt_entry_match *m, struct xt_mtchk_param *par, + unsigned int *cnt) +{ + const struct ebt_entry *e = par->entryinfo; + struct xt_match *match; + size_t left = ((char *)e + e->watchers_offset) - (char *)m; + int ret; + + if (left < sizeof(struct ebt_entry_match) || + left - sizeof(struct ebt_entry_match) < m->match_size) + return -EINVAL; + + match = xt_request_find_match(NFPROTO_BRIDGE, m->u.name, 0); + if (IS_ERR(match)) + return PTR_ERR(match); + m->u.match = match; + + par->match = match; + par->matchinfo = m->data; + ret = xt_check_match(par, m->match_size, + e->ethproto, e->invflags & EBT_IPROTO); + if (ret < 0) { + module_put(match->me); + return ret; + } + + (*cnt)++; + return 0; +} + +static inline int +ebt_check_watcher(struct ebt_entry_watcher *w, struct xt_tgchk_param *par, + unsigned int *cnt) +{ + const struct ebt_entry *e = par->entryinfo; + struct xt_target *watcher; + size_t left = ((char *)e + e->target_offset) - (char *)w; + int ret; + + if (left < sizeof(struct ebt_entry_watcher) || + left - sizeof(struct ebt_entry_watcher) < w->watcher_size) + return -EINVAL; + + watcher = xt_request_find_target(NFPROTO_BRIDGE, w->u.name, 0); + if (IS_ERR(watcher)) + return PTR_ERR(watcher); + w->u.watcher = watcher; + + par->target = watcher; + par->targinfo = w->data; + ret = xt_check_target(par, w->watcher_size, + e->ethproto, e->invflags & EBT_IPROTO); + if (ret < 0) { + module_put(watcher->me); + return ret; + } + + (*cnt)++; + return 0; +} + +static int ebt_verify_pointers(const struct ebt_replace *repl, + struct ebt_table_info *newinfo) +{ + unsigned int limit = repl->entries_size; + unsigned int valid_hooks = repl->valid_hooks; + unsigned int offset = 0; + int i; + + for (i = 0; i < NF_BR_NUMHOOKS; i++) + newinfo->hook_entry[i] = NULL; + + newinfo->entries_size = repl->entries_size; + newinfo->nentries = repl->nentries; + + while (offset < limit) { + size_t left = limit - offset; + struct ebt_entry *e = (void *)newinfo->entries + offset; + + if (left < sizeof(unsigned int)) + break; + + for (i = 0; i < NF_BR_NUMHOOKS; i++) { + if ((valid_hooks & (1 << i)) == 0) + continue; + if ((char __user *)repl->hook_entry[i] == + repl->entries + offset) + break; + } + + if (i != NF_BR_NUMHOOKS || !(e->bitmask & EBT_ENTRY_OR_ENTRIES)) { + if (e->bitmask != 0) { + /* we make userspace set this right, + so there is no misunderstanding */ + BUGPRINT("EBT_ENTRY_OR_ENTRIES shouldn't be set " + "in distinguisher\n"); + return -EINVAL; + } + if (i != NF_BR_NUMHOOKS) + newinfo->hook_entry[i] = (struct ebt_entries *)e; + if (left < sizeof(struct ebt_entries)) + break; + offset += sizeof(struct ebt_entries); + } else { + if (left < sizeof(struct ebt_entry)) + break; + if (left < e->next_offset) + break; + if (e->next_offset < sizeof(struct ebt_entry)) + return -EINVAL; + offset += e->next_offset; + } + } + if (offset != limit) { + BUGPRINT("entries_size too small\n"); + return -EINVAL; + } + + /* check if all valid hooks have a chain */ + for (i = 0; i < NF_BR_NUMHOOKS; i++) { + if (!newinfo->hook_entry[i] && + (valid_hooks & (1 << i))) { + BUGPRINT("Valid hook without chain\n"); + return -EINVAL; + } + } + return 0; +} + +/* + * this one is very careful, as it is the first function + * to parse the userspace data + */ +static inline int +ebt_check_entry_size_and_hooks(const struct ebt_entry *e, + const struct ebt_table_info *newinfo, + unsigned int *n, unsigned int *cnt, + unsigned int *totalcnt, unsigned int *udc_cnt) +{ + int i; + + for (i = 0; i < NF_BR_NUMHOOKS; i++) { + if ((void *)e == (void *)newinfo->hook_entry[i]) + break; + } + /* beginning of a new chain + if i == NF_BR_NUMHOOKS it must be a user defined chain */ + if (i != NF_BR_NUMHOOKS || !e->bitmask) { + /* this checks if the previous chain has as many entries + as it said it has */ + if (*n != *cnt) { + BUGPRINT("nentries does not equal the nr of entries " + "in the chain\n"); + return -EINVAL; + } + if (((struct ebt_entries *)e)->policy != EBT_DROP && + ((struct ebt_entries *)e)->policy != EBT_ACCEPT) { + /* only RETURN from udc */ + if (i != NF_BR_NUMHOOKS || + ((struct ebt_entries *)e)->policy != EBT_RETURN) { + BUGPRINT("bad policy\n"); + return -EINVAL; + } + } + if (i == NF_BR_NUMHOOKS) /* it's a user defined chain */ + (*udc_cnt)++; + if (((struct ebt_entries *)e)->counter_offset != *totalcnt) { + BUGPRINT("counter_offset != totalcnt"); + return -EINVAL; + } + *n = ((struct ebt_entries *)e)->nentries; + *cnt = 0; + return 0; + } + /* a plain old entry, heh */ + if (sizeof(struct ebt_entry) > e->watchers_offset || + e->watchers_offset > e->target_offset || + e->target_offset >= e->next_offset) { + BUGPRINT("entry offsets not in right order\n"); + return -EINVAL; + } + /* this is not checked anywhere else */ + if (e->next_offset - e->target_offset < sizeof(struct ebt_entry_target)) { + BUGPRINT("target size too small\n"); + return -EINVAL; + } + (*cnt)++; + (*totalcnt)++; + return 0; +} + +struct ebt_cl_stack +{ + struct ebt_chainstack cs; + int from; + unsigned int hookmask; +}; + +/* + * we need these positions to check that the jumps to a different part of the + * entries is a jump to the beginning of a new chain. + */ +static inline int +ebt_get_udc_positions(struct ebt_entry *e, struct ebt_table_info *newinfo, + unsigned int *n, struct ebt_cl_stack *udc) +{ + int i; + + /* we're only interested in chain starts */ + if (e->bitmask) + return 0; + for (i = 0; i < NF_BR_NUMHOOKS; i++) { + if (newinfo->hook_entry[i] == (struct ebt_entries *)e) + break; + } + /* only care about udc */ + if (i != NF_BR_NUMHOOKS) + return 0; + + udc[*n].cs.chaininfo = (struct ebt_entries *)e; + /* these initialisations are depended on later in check_chainloops() */ + udc[*n].cs.n = 0; + udc[*n].hookmask = 0; + + (*n)++; + return 0; +} + +static inline int +ebt_cleanup_match(struct ebt_entry_match *m, struct net *net, unsigned int *i) +{ + struct xt_mtdtor_param par; + + if (i && (*i)-- == 0) + return 1; + + par.net = net; + par.match = m->u.match; + par.matchinfo = m->data; + par.family = NFPROTO_BRIDGE; + if (par.match->destroy != NULL) + par.match->destroy(&par); + module_put(par.match->me); + return 0; +} + +static inline int +ebt_cleanup_watcher(struct ebt_entry_watcher *w, struct net *net, unsigned int *i) +{ + struct xt_tgdtor_param par; + + if (i && (*i)-- == 0) + return 1; + + par.net = net; + par.target = w->u.watcher; + par.targinfo = w->data; + par.family = NFPROTO_BRIDGE; + if (par.target->destroy != NULL) + par.target->destroy(&par); + module_put(par.target->me); + return 0; +} + +static inline int +ebt_cleanup_entry(struct ebt_entry *e, struct net *net, unsigned int *cnt) +{ + struct xt_tgdtor_param par; + struct ebt_entry_target *t; + + if (e->bitmask == 0) + return 0; + /* we're done */ + if (cnt && (*cnt)-- == 0) + return 1; + EBT_WATCHER_ITERATE(e, ebt_cleanup_watcher, net, NULL); + EBT_MATCH_ITERATE(e, ebt_cleanup_match, net, NULL); + t = (struct ebt_entry_target *)(((char *)e) + e->target_offset); + + par.net = net; + par.target = t->u.target; + par.targinfo = t->data; + par.family = NFPROTO_BRIDGE; + if (par.target->destroy != NULL) + par.target->destroy(&par); + module_put(par.target->me); + return 0; +} + +static inline int +ebt_check_entry(struct ebt_entry *e, struct net *net, + const struct ebt_table_info *newinfo, + const char *name, unsigned int *cnt, + struct ebt_cl_stack *cl_s, unsigned int udc_cnt) +{ + struct ebt_entry_target *t; + struct xt_target *target; + unsigned int i, j, hook = 0, hookmask = 0; + size_t gap; + int ret; + struct xt_mtchk_param mtpar; + struct xt_tgchk_param tgpar; + + /* don't mess with the struct ebt_entries */ + if (e->bitmask == 0) + return 0; + + if (e->bitmask & ~EBT_F_MASK) { + BUGPRINT("Unknown flag for bitmask\n"); + return -EINVAL; + } + if (e->invflags & ~EBT_INV_MASK) { + BUGPRINT("Unknown flag for inv bitmask\n"); + return -EINVAL; + } + if ( (e->bitmask & EBT_NOPROTO) && (e->bitmask & EBT_802_3) ) { + BUGPRINT("NOPROTO & 802_3 not allowed\n"); + return -EINVAL; + } + /* what hook do we belong to? */ + for (i = 0; i < NF_BR_NUMHOOKS; i++) { + if (!newinfo->hook_entry[i]) + continue; + if ((char *)newinfo->hook_entry[i] < (char *)e) + hook = i; + else + break; + } + /* (1 << NF_BR_NUMHOOKS) tells the check functions the rule is on + a base chain */ + if (i < NF_BR_NUMHOOKS) + hookmask = (1 << hook) | (1 << NF_BR_NUMHOOKS); + else { + for (i = 0; i < udc_cnt; i++) + if ((char *)(cl_s[i].cs.chaininfo) > (char *)e) + break; + if (i == 0) + hookmask = (1 << hook) | (1 << NF_BR_NUMHOOKS); + else + hookmask = cl_s[i - 1].hookmask; + } + i = 0; + + mtpar.net = tgpar.net = net; + mtpar.table = tgpar.table = name; + mtpar.entryinfo = tgpar.entryinfo = e; + mtpar.hook_mask = tgpar.hook_mask = hookmask; + mtpar.family = tgpar.family = NFPROTO_BRIDGE; + ret = EBT_MATCH_ITERATE(e, ebt_check_match, &mtpar, &i); + if (ret != 0) + goto cleanup_matches; + j = 0; + ret = EBT_WATCHER_ITERATE(e, ebt_check_watcher, &tgpar, &j); + if (ret != 0) + goto cleanup_watchers; + t = (struct ebt_entry_target *)(((char *)e) + e->target_offset); + gap = e->next_offset - e->target_offset; + + target = xt_request_find_target(NFPROTO_BRIDGE, t->u.name, 0); + if (IS_ERR(target)) { + ret = PTR_ERR(target); + goto cleanup_watchers; + } + + t->u.target = target; + if (t->u.target == &ebt_standard_target) { + if (gap < sizeof(struct ebt_standard_target)) { + BUGPRINT("Standard target size too big\n"); + ret = -EFAULT; + goto cleanup_watchers; + } + if (((struct ebt_standard_target *)t)->verdict < + -NUM_STANDARD_TARGETS) { + BUGPRINT("Invalid standard target\n"); + ret = -EFAULT; + goto cleanup_watchers; + } + } else if (t->target_size > gap - sizeof(struct ebt_entry_target)) { + module_put(t->u.target->me); + ret = -EFAULT; + goto cleanup_watchers; + } + + tgpar.target = target; + tgpar.targinfo = t->data; + ret = xt_check_target(&tgpar, t->target_size, + e->ethproto, e->invflags & EBT_IPROTO); + if (ret < 0) { + module_put(target->me); + goto cleanup_watchers; + } + (*cnt)++; + return 0; +cleanup_watchers: + EBT_WATCHER_ITERATE(e, ebt_cleanup_watcher, net, &j); +cleanup_matches: + EBT_MATCH_ITERATE(e, ebt_cleanup_match, net, &i); + return ret; +} + +/* + * checks for loops and sets the hook mask for udc + * the hook mask for udc tells us from which base chains the udc can be + * accessed. This mask is a parameter to the check() functions of the extensions + */ +static int check_chainloops(const struct ebt_entries *chain, struct ebt_cl_stack *cl_s, + unsigned int udc_cnt, unsigned int hooknr, char *base) +{ + int i, chain_nr = -1, pos = 0, nentries = chain->nentries, verdict; + const struct ebt_entry *e = (struct ebt_entry *)chain->data; + const struct ebt_entry_target *t; + + while (pos < nentries || chain_nr != -1) { + /* end of udc, go back one 'recursion' step */ + if (pos == nentries) { + /* put back values of the time when this chain was called */ + e = cl_s[chain_nr].cs.e; + if (cl_s[chain_nr].from != -1) + nentries = + cl_s[cl_s[chain_nr].from].cs.chaininfo->nentries; + else + nentries = chain->nentries; + pos = cl_s[chain_nr].cs.n; + /* make sure we won't see a loop that isn't one */ + cl_s[chain_nr].cs.n = 0; + chain_nr = cl_s[chain_nr].from; + if (pos == nentries) + continue; + } + t = (struct ebt_entry_target *) + (((char *)e) + e->target_offset); + if (strcmp(t->u.name, EBT_STANDARD_TARGET)) + goto letscontinue; + if (e->target_offset + sizeof(struct ebt_standard_target) > + e->next_offset) { + BUGPRINT("Standard target size too big\n"); + return -1; + } + verdict = ((struct ebt_standard_target *)t)->verdict; + if (verdict >= 0) { /* jump to another chain */ + struct ebt_entries *hlp2 = + (struct ebt_entries *)(base + verdict); + for (i = 0; i < udc_cnt; i++) + if (hlp2 == cl_s[i].cs.chaininfo) + break; + /* bad destination or loop */ + if (i == udc_cnt) { + BUGPRINT("bad destination\n"); + return -1; + } + if (cl_s[i].cs.n) { + BUGPRINT("loop\n"); + return -1; + } + if (cl_s[i].hookmask & (1 << hooknr)) + goto letscontinue; + /* this can't be 0, so the loop test is correct */ + cl_s[i].cs.n = pos + 1; + pos = 0; + cl_s[i].cs.e = ebt_next_entry(e); + e = (struct ebt_entry *)(hlp2->data); + nentries = hlp2->nentries; + cl_s[i].from = chain_nr; + chain_nr = i; + /* this udc is accessible from the base chain for hooknr */ + cl_s[i].hookmask |= (1 << hooknr); + continue; + } +letscontinue: + e = ebt_next_entry(e); + pos++; + } + return 0; +} + +/* do the parsing of the table/chains/entries/matches/watchers/targets, heh */ +static int translate_table(struct net *net, const char *name, + struct ebt_table_info *newinfo) +{ + unsigned int i, j, k, udc_cnt; + int ret; + struct ebt_cl_stack *cl_s = NULL; /* used in the checking for chain loops */ + + i = 0; + while (i < NF_BR_NUMHOOKS && !newinfo->hook_entry[i]) + i++; + if (i == NF_BR_NUMHOOKS) { + BUGPRINT("No valid hooks specified\n"); + return -EINVAL; + } + if (newinfo->hook_entry[i] != (struct ebt_entries *)newinfo->entries) { + BUGPRINT("Chains don't start at beginning\n"); + return -EINVAL; + } + /* make sure chains are ordered after each other in same order + as their corresponding hooks */ + for (j = i + 1; j < NF_BR_NUMHOOKS; j++) { + if (!newinfo->hook_entry[j]) + continue; + if (newinfo->hook_entry[j] <= newinfo->hook_entry[i]) { + BUGPRINT("Hook order must be followed\n"); + return -EINVAL; + } + i = j; + } + + /* do some early checkings and initialize some things */ + i = 0; /* holds the expected nr. of entries for the chain */ + j = 0; /* holds the up to now counted entries for the chain */ + k = 0; /* holds the total nr. of entries, should equal + newinfo->nentries afterwards */ + udc_cnt = 0; /* will hold the nr. of user defined chains (udc) */ + ret = EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size, + ebt_check_entry_size_and_hooks, newinfo, + &i, &j, &k, &udc_cnt); + + if (ret != 0) + return ret; + + if (i != j) { + BUGPRINT("nentries does not equal the nr of entries in the " + "(last) chain\n"); + return -EINVAL; + } + if (k != newinfo->nentries) { + BUGPRINT("Total nentries is wrong\n"); + return -EINVAL; + } + + /* get the location of the udc, put them in an array + while we're at it, allocate the chainstack */ + if (udc_cnt) { + /* this will get free'd in do_replace()/ebt_register_table() + if an error occurs */ + newinfo->chainstack = + vmalloc(nr_cpu_ids * sizeof(*(newinfo->chainstack))); + if (!newinfo->chainstack) + return -ENOMEM; + for_each_possible_cpu(i) { + newinfo->chainstack[i] = + vmalloc(udc_cnt * sizeof(*(newinfo->chainstack[0]))); + if (!newinfo->chainstack[i]) { + while (i) + vfree(newinfo->chainstack[--i]); + vfree(newinfo->chainstack); + newinfo->chainstack = NULL; + return -ENOMEM; + } + } + + cl_s = vmalloc(udc_cnt * sizeof(*cl_s)); + if (!cl_s) + return -ENOMEM; + i = 0; /* the i'th udc */ + EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size, + ebt_get_udc_positions, newinfo, &i, cl_s); + /* sanity check */ + if (i != udc_cnt) { + BUGPRINT("i != udc_cnt\n"); + vfree(cl_s); + return -EFAULT; + } + } + + /* Check for loops */ + for (i = 0; i < NF_BR_NUMHOOKS; i++) + if (newinfo->hook_entry[i]) + if (check_chainloops(newinfo->hook_entry[i], + cl_s, udc_cnt, i, newinfo->entries)) { + vfree(cl_s); + return -EINVAL; + } + + /* we now know the following (along with E=mc²): + - the nr of entries in each chain is right + - the size of the allocated space is right + - all valid hooks have a corresponding chain + - there are no loops + - wrong data can still be on the level of a single entry + - could be there are jumps to places that are not the + beginning of a chain. This can only occur in chains that + are not accessible from any base chains, so we don't care. */ + + /* used to know what we need to clean up if something goes wrong */ + i = 0; + ret = EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size, + ebt_check_entry, net, newinfo, name, &i, cl_s, udc_cnt); + if (ret != 0) { + EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size, + ebt_cleanup_entry, net, &i); + } + vfree(cl_s); + return ret; +} + +/* called under write_lock */ +static void get_counters(const struct ebt_counter *oldcounters, + struct ebt_counter *counters, unsigned int nentries) +{ + int i, cpu; + struct ebt_counter *counter_base; + + /* counters of cpu 0 */ + memcpy(counters, oldcounters, + sizeof(struct ebt_counter) * nentries); + + /* add other counters to those of cpu 0 */ + for_each_possible_cpu(cpu) { + if (cpu == 0) + continue; + counter_base = COUNTER_BASE(oldcounters, nentries, cpu); + for (i = 0; i < nentries; i++) { + counters[i].pcnt += counter_base[i].pcnt; + counters[i].bcnt += counter_base[i].bcnt; + } + } +} + +static int do_replace_finish(struct net *net, struct ebt_replace *repl, + struct ebt_table_info *newinfo) +{ + int ret, i; + struct ebt_counter *counterstmp = NULL; + /* used to be able to unlock earlier */ + struct ebt_table_info *table; + struct ebt_table *t; + + /* the user wants counters back + the check on the size is done later, when we have the lock */ + if (repl->num_counters) { + unsigned long size = repl->num_counters * sizeof(*counterstmp); + counterstmp = vmalloc(size); + if (!counterstmp) + return -ENOMEM; + } + + newinfo->chainstack = NULL; + ret = ebt_verify_pointers(repl, newinfo); + if (ret != 0) + goto free_counterstmp; + + ret = translate_table(net, repl->name, newinfo); + + if (ret != 0) + goto free_counterstmp; + + t = find_table_lock(net, repl->name, &ret, &ebt_mutex); + if (!t) { + ret = -ENOENT; + goto free_iterate; + } + + /* the table doesn't like it */ + if (t->check && (ret = t->check(newinfo, repl->valid_hooks))) + goto free_unlock; + + if (repl->num_counters && repl->num_counters != t->private->nentries) { + BUGPRINT("Wrong nr. of counters requested\n"); + ret = -EINVAL; + goto free_unlock; + } + + /* we have the mutex lock, so no danger in reading this pointer */ + table = t->private; + /* make sure the table can only be rmmod'ed if it contains no rules */ + if (!table->nentries && newinfo->nentries && !try_module_get(t->me)) { + ret = -ENOENT; + goto free_unlock; + } else if (table->nentries && !newinfo->nentries) + module_put(t->me); + /* we need an atomic snapshot of the counters */ + write_lock_bh(&t->lock); + if (repl->num_counters) + get_counters(t->private->counters, counterstmp, + t->private->nentries); + + t->private = newinfo; + write_unlock_bh(&t->lock); + mutex_unlock(&ebt_mutex); + /* so, a user can change the chains while having messed up her counter + allocation. Only reason why this is done is because this way the lock + is held only once, while this doesn't bring the kernel into a + dangerous state. */ + if (repl->num_counters && + copy_to_user(repl->counters, counterstmp, + repl->num_counters * sizeof(struct ebt_counter))) { + ret = -EFAULT; + } + else + ret = 0; + + /* decrease module count and free resources */ + EBT_ENTRY_ITERATE(table->entries, table->entries_size, + ebt_cleanup_entry, net, NULL); + + vfree(table->entries); + if (table->chainstack) { + for_each_possible_cpu(i) + vfree(table->chainstack[i]); + vfree(table->chainstack); + } + vfree(table); + + vfree(counterstmp); + return ret; + +free_unlock: + mutex_unlock(&ebt_mutex); +free_iterate: + EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size, + ebt_cleanup_entry, net, NULL); +free_counterstmp: + vfree(counterstmp); + /* can be initialized in translate_table() */ + if (newinfo->chainstack) { + for_each_possible_cpu(i) + vfree(newinfo->chainstack[i]); + vfree(newinfo->chainstack); + } + return ret; +} + +/* replace the table */ +static int do_replace(struct net *net, const void __user *user, + unsigned int len) +{ + int ret, countersize; + struct ebt_table_info *newinfo; + struct ebt_replace tmp; + + if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) + return -EFAULT; + + if (len != sizeof(tmp) + tmp.entries_size) { + BUGPRINT("Wrong len argument\n"); + return -EINVAL; + } + + if (tmp.entries_size == 0) { + BUGPRINT("Entries_size never zero\n"); + return -EINVAL; + } + /* overflow check */ + if (tmp.nentries >= ((INT_MAX - sizeof(struct ebt_table_info)) / + NR_CPUS - SMP_CACHE_BYTES) / sizeof(struct ebt_counter)) + return -ENOMEM; + if (tmp.num_counters >= INT_MAX / sizeof(struct ebt_counter)) + return -ENOMEM; + + tmp.name[sizeof(tmp.name) - 1] = 0; + + countersize = COUNTER_OFFSET(tmp.nentries) * nr_cpu_ids; + newinfo = vmalloc(sizeof(*newinfo) + countersize); + if (!newinfo) + return -ENOMEM; + + if (countersize) + memset(newinfo->counters, 0, countersize); + + newinfo->entries = vmalloc(tmp.entries_size); + if (!newinfo->entries) { + ret = -ENOMEM; + goto free_newinfo; + } + if (copy_from_user( + newinfo->entries, tmp.entries, tmp.entries_size) != 0) { + BUGPRINT("Couldn't copy entries from userspace\n"); + ret = -EFAULT; + goto free_entries; + } + + ret = do_replace_finish(net, &tmp, newinfo); + if (ret == 0) + return ret; +free_entries: + vfree(newinfo->entries); +free_newinfo: + vfree(newinfo); + return ret; +} + +struct ebt_table * +ebt_register_table(struct net *net, const struct ebt_table *input_table) +{ + struct ebt_table_info *newinfo; + struct ebt_table *t, *table; + struct ebt_replace_kernel *repl; + int ret, i, countersize; + void *p; + + if (input_table == NULL || (repl = input_table->table) == NULL || + repl->entries == NULL || repl->entries_size == 0 || + repl->counters != NULL || input_table->private != NULL) { + BUGPRINT("Bad table data for ebt_register_table!!!\n"); + return ERR_PTR(-EINVAL); + } + + /* Don't add one table to multiple lists. */ + table = kmemdup(input_table, sizeof(struct ebt_table), GFP_KERNEL); + if (!table) { + ret = -ENOMEM; + goto out; + } + + countersize = COUNTER_OFFSET(repl->nentries) * nr_cpu_ids; + newinfo = vmalloc(sizeof(*newinfo) + countersize); + ret = -ENOMEM; + if (!newinfo) + goto free_table; + + p = vmalloc(repl->entries_size); + if (!p) + goto free_newinfo; + + memcpy(p, repl->entries, repl->entries_size); + newinfo->entries = p; + + newinfo->entries_size = repl->entries_size; + newinfo->nentries = repl->nentries; + + if (countersize) + memset(newinfo->counters, 0, countersize); + + /* fill in newinfo and parse the entries */ + newinfo->chainstack = NULL; + for (i = 0; i < NF_BR_NUMHOOKS; i++) { + if ((repl->valid_hooks & (1 << i)) == 0) + newinfo->hook_entry[i] = NULL; + else + newinfo->hook_entry[i] = p + + ((char *)repl->hook_entry[i] - repl->entries); + } + ret = translate_table(net, repl->name, newinfo); + if (ret != 0) { + BUGPRINT("Translate_table failed\n"); + goto free_chainstack; + } + + if (table->check && table->check(newinfo, table->valid_hooks)) { + BUGPRINT("The table doesn't like its own initial data, lol\n"); + ret = -EINVAL; + goto free_chainstack; + } + + table->private = newinfo; + rwlock_init(&table->lock); + ret = mutex_lock_interruptible(&ebt_mutex); + if (ret != 0) + goto free_chainstack; + + list_for_each_entry(t, &net->xt.tables[NFPROTO_BRIDGE], list) { + if (strcmp(t->name, table->name) == 0) { + ret = -EEXIST; + BUGPRINT("Table name already exists\n"); + goto free_unlock; + } + } + + /* Hold a reference count if the chains aren't empty */ + if (newinfo->nentries && !try_module_get(table->me)) { + ret = -ENOENT; + goto free_unlock; + } + list_add(&table->list, &net->xt.tables[NFPROTO_BRIDGE]); + mutex_unlock(&ebt_mutex); + return table; +free_unlock: + mutex_unlock(&ebt_mutex); +free_chainstack: + if (newinfo->chainstack) { + for_each_possible_cpu(i) + vfree(newinfo->chainstack[i]); + vfree(newinfo->chainstack); + } + vfree(newinfo->entries); +free_newinfo: + vfree(newinfo); +free_table: + kfree(table); +out: + return ERR_PTR(ret); +} + +void ebt_unregister_table(struct net *net, struct ebt_table *table) +{ + int i; + + if (!table) { + BUGPRINT("Request to unregister NULL table!!!\n"); + return; + } + mutex_lock(&ebt_mutex); + list_del(&table->list); + mutex_unlock(&ebt_mutex); + EBT_ENTRY_ITERATE(table->private->entries, table->private->entries_size, + ebt_cleanup_entry, net, NULL); + if (table->private->nentries) + module_put(table->me); + vfree(table->private->entries); + if (table->private->chainstack) { + for_each_possible_cpu(i) + vfree(table->private->chainstack[i]); + vfree(table->private->chainstack); + } + vfree(table->private); + kfree(table); +} + +/* userspace just supplied us with counters */ +static int do_update_counters(struct net *net, const char *name, + struct ebt_counter __user *counters, + unsigned int num_counters, + const void __user *user, unsigned int len) +{ + int i, ret; + struct ebt_counter *tmp; + struct ebt_table *t; + + if (num_counters == 0) + return -EINVAL; + + tmp = vmalloc(num_counters * sizeof(*tmp)); + if (!tmp) + return -ENOMEM; + + t = find_table_lock(net, name, &ret, &ebt_mutex); + if (!t) + goto free_tmp; + + if (num_counters != t->private->nentries) { + BUGPRINT("Wrong nr of counters\n"); + ret = -EINVAL; + goto unlock_mutex; + } + + if (copy_from_user(tmp, counters, num_counters * sizeof(*counters))) { + ret = -EFAULT; + goto unlock_mutex; + } + + /* we want an atomic add of the counters */ + write_lock_bh(&t->lock); + + /* we add to the counters of the first cpu */ + for (i = 0; i < num_counters; i++) { + t->private->counters[i].pcnt += tmp[i].pcnt; + t->private->counters[i].bcnt += tmp[i].bcnt; + } + + write_unlock_bh(&t->lock); + ret = 0; +unlock_mutex: + mutex_unlock(&ebt_mutex); +free_tmp: + vfree(tmp); + return ret; +} + +static int update_counters(struct net *net, const void __user *user, + unsigned int len) +{ + struct ebt_replace hlp; + + if (copy_from_user(&hlp, user, sizeof(hlp))) + return -EFAULT; + + if (len != sizeof(hlp) + hlp.num_counters * sizeof(struct ebt_counter)) + return -EINVAL; + + return do_update_counters(net, hlp.name, hlp.counters, + hlp.num_counters, user, len); +} + +static inline int ebt_make_matchname(const struct ebt_entry_match *m, + const char *base, char __user *ubase) +{ + char __user *hlp = ubase + ((char *)m - base); + char name[EBT_FUNCTION_MAXNAMELEN] = {}; + + /* ebtables expects 32 bytes long names but xt_match names are 29 bytes + long. Copy 29 bytes and fill remaining bytes with zeroes. */ + strncpy(name, m->u.match->name, sizeof(name)); + if (copy_to_user(hlp, name, EBT_FUNCTION_MAXNAMELEN)) + return -EFAULT; + return 0; +} + +static inline int ebt_make_watchername(const struct ebt_entry_watcher *w, + const char *base, char __user *ubase) +{ + char __user *hlp = ubase + ((char *)w - base); + char name[EBT_FUNCTION_MAXNAMELEN] = {}; + + strncpy(name, w->u.watcher->name, sizeof(name)); + if (copy_to_user(hlp , name, EBT_FUNCTION_MAXNAMELEN)) + return -EFAULT; + return 0; +} + +static inline int +ebt_make_names(struct ebt_entry *e, const char *base, char __user *ubase) +{ + int ret; + char __user *hlp; + const struct ebt_entry_target *t; + char name[EBT_FUNCTION_MAXNAMELEN] = {}; + + if (e->bitmask == 0) + return 0; + + hlp = ubase + (((char *)e + e->target_offset) - base); + t = (struct ebt_entry_target *)(((char *)e) + e->target_offset); + + ret = EBT_MATCH_ITERATE(e, ebt_make_matchname, base, ubase); + if (ret != 0) + return ret; + ret = EBT_WATCHER_ITERATE(e, ebt_make_watchername, base, ubase); + if (ret != 0) + return ret; + strncpy(name, t->u.target->name, sizeof(name)); + if (copy_to_user(hlp, name, EBT_FUNCTION_MAXNAMELEN)) + return -EFAULT; + return 0; +} + +static int copy_counters_to_user(struct ebt_table *t, + const struct ebt_counter *oldcounters, + void __user *user, unsigned int num_counters, + unsigned int nentries) +{ + struct ebt_counter *counterstmp; + int ret = 0; + + /* userspace might not need the counters */ + if (num_counters == 0) + return 0; + + if (num_counters != nentries) { + BUGPRINT("Num_counters wrong\n"); + return -EINVAL; + } + + counterstmp = vmalloc(nentries * sizeof(*counterstmp)); + if (!counterstmp) + return -ENOMEM; + + write_lock_bh(&t->lock); + get_counters(oldcounters, counterstmp, nentries); + write_unlock_bh(&t->lock); + + if (copy_to_user(user, counterstmp, + nentries * sizeof(struct ebt_counter))) + ret = -EFAULT; + vfree(counterstmp); + return ret; +} + +/* called with ebt_mutex locked */ +static int copy_everything_to_user(struct ebt_table *t, void __user *user, + const int *len, int cmd) +{ + struct ebt_replace tmp; + const struct ebt_counter *oldcounters; + unsigned int entries_size, nentries; + int ret; + char *entries; + + if (cmd == EBT_SO_GET_ENTRIES) { + entries_size = t->private->entries_size; + nentries = t->private->nentries; + entries = t->private->entries; + oldcounters = t->private->counters; + } else { + entries_size = t->table->entries_size; + nentries = t->table->nentries; + entries = t->table->entries; + oldcounters = t->table->counters; + } + + if (copy_from_user(&tmp, user, sizeof(tmp))) + return -EFAULT; + + if (*len != sizeof(struct ebt_replace) + entries_size + + (tmp.num_counters? nentries * sizeof(struct ebt_counter): 0)) + return -EINVAL; + + if (tmp.nentries != nentries) { + BUGPRINT("Nentries wrong\n"); + return -EINVAL; + } + + if (tmp.entries_size != entries_size) { + BUGPRINT("Wrong size\n"); + return -EINVAL; + } + + ret = copy_counters_to_user(t, oldcounters, tmp.counters, + tmp.num_counters, nentries); + if (ret) + return ret; + + if (copy_to_user(tmp.entries, entries, entries_size)) { + BUGPRINT("Couldn't copy entries to userspace\n"); + return -EFAULT; + } + /* set the match/watcher/target names right */ + return EBT_ENTRY_ITERATE(entries, entries_size, + ebt_make_names, entries, tmp.entries); +} + +static int do_ebt_set_ctl(struct sock *sk, + int cmd, void __user *user, unsigned int len) +{ + int ret; + + if (!capable(CAP_NET_ADMIN)) + return -EPERM; + + switch(cmd) { + case EBT_SO_SET_ENTRIES: + ret = do_replace(sock_net(sk), user, len); + break; + case EBT_SO_SET_COUNTERS: + ret = update_counters(sock_net(sk), user, len); + break; + default: + ret = -EINVAL; + } + return ret; +} + +static int do_ebt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) +{ + int ret; + struct ebt_replace tmp; + struct ebt_table *t; + + if (!capable(CAP_NET_ADMIN)) + return -EPERM; + + if (copy_from_user(&tmp, user, sizeof(tmp))) + return -EFAULT; + + t = find_table_lock(sock_net(sk), tmp.name, &ret, &ebt_mutex); + if (!t) + return ret; + + switch(cmd) { + case EBT_SO_GET_INFO: + case EBT_SO_GET_INIT_INFO: + if (*len != sizeof(struct ebt_replace)){ + ret = -EINVAL; + mutex_unlock(&ebt_mutex); + break; + } + if (cmd == EBT_SO_GET_INFO) { + tmp.nentries = t->private->nentries; + tmp.entries_size = t->private->entries_size; + tmp.valid_hooks = t->valid_hooks; + } else { + tmp.nentries = t->table->nentries; + tmp.entries_size = t->table->entries_size; + tmp.valid_hooks = t->table->valid_hooks; + } + mutex_unlock(&ebt_mutex); + if (copy_to_user(user, &tmp, *len) != 0){ + BUGPRINT("c2u Didn't work\n"); + ret = -EFAULT; + break; + } + ret = 0; + break; + + case EBT_SO_GET_ENTRIES: + case EBT_SO_GET_INIT_ENTRIES: + ret = copy_everything_to_user(t, user, len, cmd); + mutex_unlock(&ebt_mutex); + break; + + default: + mutex_unlock(&ebt_mutex); + ret = -EINVAL; + } + + return ret; +} + +#ifdef CONFIG_COMPAT +/* 32 bit-userspace compatibility definitions. */ +struct compat_ebt_replace { + char name[EBT_TABLE_MAXNAMELEN]; + compat_uint_t valid_hooks; + compat_uint_t nentries; + compat_uint_t entries_size; + /* start of the chains */ + compat_uptr_t hook_entry[NF_BR_NUMHOOKS]; + /* nr of counters userspace expects back */ + compat_uint_t num_counters; + /* where the kernel will put the old counters. */ + compat_uptr_t counters; + compat_uptr_t entries; +}; + +/* struct ebt_entry_match, _target and _watcher have same layout */ +struct compat_ebt_entry_mwt { + union { + char name[EBT_FUNCTION_MAXNAMELEN]; + compat_uptr_t ptr; + } u; + compat_uint_t match_size; + compat_uint_t data[0]; +}; + +/* account for possible padding between match_size and ->data */ +static int ebt_compat_entry_padsize(void) +{ + BUILD_BUG_ON(XT_ALIGN(sizeof(struct ebt_entry_match)) < + COMPAT_XT_ALIGN(sizeof(struct compat_ebt_entry_mwt))); + return (int) XT_ALIGN(sizeof(struct ebt_entry_match)) - + COMPAT_XT_ALIGN(sizeof(struct compat_ebt_entry_mwt)); +} + +static int ebt_compat_match_offset(const struct xt_match *match, + unsigned int userlen) +{ + /* + * ebt_among needs special handling. The kernel .matchsize is + * set to -1 at registration time; at runtime an EBT_ALIGN()ed + * value is expected. + * Example: userspace sends 4500, ebt_among.c wants 4504. + */ + if (unlikely(match->matchsize == -1)) + return XT_ALIGN(userlen) - COMPAT_XT_ALIGN(userlen); + return xt_compat_match_offset(match); +} + +static int compat_match_to_user(struct ebt_entry_match *m, void __user **dstptr, + unsigned int *size) +{ + const struct xt_match *match = m->u.match; + struct compat_ebt_entry_mwt __user *cm = *dstptr; + int off = ebt_compat_match_offset(match, m->match_size); + compat_uint_t msize = m->match_size - off; + + BUG_ON(off >= m->match_size); + + if (copy_to_user(cm->u.name, match->name, + strlen(match->name) + 1) || put_user(msize, &cm->match_size)) + return -EFAULT; + + if (match->compat_to_user) { + if (match->compat_to_user(cm->data, m->data)) + return -EFAULT; + } else if (copy_to_user(cm->data, m->data, msize)) + return -EFAULT; + + *size -= ebt_compat_entry_padsize() + off; + *dstptr = cm->data; + *dstptr += msize; + return 0; +} + +static int compat_target_to_user(struct ebt_entry_target *t, + void __user **dstptr, + unsigned int *size) +{ + const struct xt_target *target = t->u.target; + struct compat_ebt_entry_mwt __user *cm = *dstptr; + int off = xt_compat_target_offset(target); + compat_uint_t tsize = t->target_size - off; + + BUG_ON(off >= t->target_size); + + if (copy_to_user(cm->u.name, target->name, + strlen(target->name) + 1) || put_user(tsize, &cm->match_size)) + return -EFAULT; + + if (target->compat_to_user) { + if (target->compat_to_user(cm->data, t->data)) + return -EFAULT; + } else if (copy_to_user(cm->data, t->data, tsize)) + return -EFAULT; + + *size -= ebt_compat_entry_padsize() + off; + *dstptr = cm->data; + *dstptr += tsize; + return 0; +} + +static int compat_watcher_to_user(struct ebt_entry_watcher *w, + void __user **dstptr, + unsigned int *size) +{ + return compat_target_to_user((struct ebt_entry_target *)w, + dstptr, size); +} + +static int compat_copy_entry_to_user(struct ebt_entry *e, void __user **dstptr, + unsigned int *size) +{ + struct ebt_entry_target *t; + struct ebt_entry __user *ce; + u32 watchers_offset, target_offset, next_offset; + compat_uint_t origsize; + int ret; + + if (e->bitmask == 0) { + if (*size < sizeof(struct ebt_entries)) + return -EINVAL; + if (copy_to_user(*dstptr, e, sizeof(struct ebt_entries))) + return -EFAULT; + + *dstptr += sizeof(struct ebt_entries); + *size -= sizeof(struct ebt_entries); + return 0; + } + + if (*size < sizeof(*ce)) + return -EINVAL; + + ce = (struct ebt_entry __user *)*dstptr; + if (copy_to_user(ce, e, sizeof(*ce))) + return -EFAULT; + + origsize = *size; + *dstptr += sizeof(*ce); + + ret = EBT_MATCH_ITERATE(e, compat_match_to_user, dstptr, size); + if (ret) + return ret; + watchers_offset = e->watchers_offset - (origsize - *size); + + ret = EBT_WATCHER_ITERATE(e, compat_watcher_to_user, dstptr, size); + if (ret) + return ret; + target_offset = e->target_offset - (origsize - *size); + + t = (struct ebt_entry_target *) ((char *) e + e->target_offset); + + ret = compat_target_to_user(t, dstptr, size); + if (ret) + return ret; + next_offset = e->next_offset - (origsize - *size); + + if (put_user(watchers_offset, &ce->watchers_offset) || + put_user(target_offset, &ce->target_offset) || + put_user(next_offset, &ce->next_offset)) + return -EFAULT; + + *size -= sizeof(*ce); + return 0; +} + +static int compat_calc_match(struct ebt_entry_match *m, int *off) +{ + *off += ebt_compat_match_offset(m->u.match, m->match_size); + *off += ebt_compat_entry_padsize(); + return 0; +} + +static int compat_calc_watcher(struct ebt_entry_watcher *w, int *off) +{ + *off += xt_compat_target_offset(w->u.watcher); + *off += ebt_compat_entry_padsize(); + return 0; +} + +static int compat_calc_entry(const struct ebt_entry *e, + const struct ebt_table_info *info, + const void *base, + struct compat_ebt_replace *newinfo) +{ + const struct ebt_entry_target *t; + unsigned int entry_offset; + int off, ret, i; + + if (e->bitmask == 0) + return 0; + + off = 0; + entry_offset = (void *)e - base; + + EBT_MATCH_ITERATE(e, compat_calc_match, &off); + EBT_WATCHER_ITERATE(e, compat_calc_watcher, &off); + + t = (const struct ebt_entry_target *) ((char *) e + e->target_offset); + + off += xt_compat_target_offset(t->u.target); + off += ebt_compat_entry_padsize(); + + newinfo->entries_size -= off; + + ret = xt_compat_add_offset(NFPROTO_BRIDGE, entry_offset, off); + if (ret) + return ret; + + for (i = 0; i < NF_BR_NUMHOOKS; i++) { + const void *hookptr = info->hook_entry[i]; + if (info->hook_entry[i] && + (e < (struct ebt_entry *)(base - hookptr))) { + newinfo->hook_entry[i] -= off; + pr_debug("0x%08X -> 0x%08X\n", + newinfo->hook_entry[i] + off, + newinfo->hook_entry[i]); + } + } + + return 0; +} + + +static int compat_table_info(const struct ebt_table_info *info, + struct compat_ebt_replace *newinfo) +{ + unsigned int size = info->entries_size; + const void *entries = info->entries; + + newinfo->entries_size = size; + + xt_compat_init_offsets(NFPROTO_BRIDGE, info->nentries); + return EBT_ENTRY_ITERATE(entries, size, compat_calc_entry, info, + entries, newinfo); +} + +static int compat_copy_everything_to_user(struct ebt_table *t, + void __user *user, int *len, int cmd) +{ + struct compat_ebt_replace repl, tmp; + struct ebt_counter *oldcounters; + struct ebt_table_info tinfo; + int ret; + void __user *pos; + + memset(&tinfo, 0, sizeof(tinfo)); + + if (cmd == EBT_SO_GET_ENTRIES) { + tinfo.entries_size = t->private->entries_size; + tinfo.nentries = t->private->nentries; + tinfo.entries = t->private->entries; + oldcounters = t->private->counters; + } else { + tinfo.entries_size = t->table->entries_size; + tinfo.nentries = t->table->nentries; + tinfo.entries = t->table->entries; + oldcounters = t->table->counters; + } + + if (copy_from_user(&tmp, user, sizeof(tmp))) + return -EFAULT; + + if (tmp.nentries != tinfo.nentries || + (tmp.num_counters && tmp.num_counters != tinfo.nentries)) + return -EINVAL; + + memcpy(&repl, &tmp, sizeof(repl)); + if (cmd == EBT_SO_GET_ENTRIES) + ret = compat_table_info(t->private, &repl); + else + ret = compat_table_info(&tinfo, &repl); + if (ret) + return ret; + + if (*len != sizeof(tmp) + repl.entries_size + + (tmp.num_counters? tinfo.nentries * sizeof(struct ebt_counter): 0)) { + pr_err("wrong size: *len %d, entries_size %u, replsz %d\n", + *len, tinfo.entries_size, repl.entries_size); + return -EINVAL; + } + + /* userspace might not need the counters */ + ret = copy_counters_to_user(t, oldcounters, compat_ptr(tmp.counters), + tmp.num_counters, tinfo.nentries); + if (ret) + return ret; + + pos = compat_ptr(tmp.entries); + return EBT_ENTRY_ITERATE(tinfo.entries, tinfo.entries_size, + compat_copy_entry_to_user, &pos, &tmp.entries_size); +} + +struct ebt_entries_buf_state { + char *buf_kern_start; /* kernel buffer to copy (translated) data to */ + u32 buf_kern_len; /* total size of kernel buffer */ + u32 buf_kern_offset; /* amount of data copied so far */ + u32 buf_user_offset; /* read position in userspace buffer */ +}; + +static int ebt_buf_count(struct ebt_entries_buf_state *state, unsigned int sz) +{ + state->buf_kern_offset += sz; + return state->buf_kern_offset >= sz ? 0 : -EINVAL; +} + +static int ebt_buf_add(struct ebt_entries_buf_state *state, + void *data, unsigned int sz) +{ + if (state->buf_kern_start == NULL) + goto count_only; + + BUG_ON(state->buf_kern_offset + sz > state->buf_kern_len); + + memcpy(state->buf_kern_start + state->buf_kern_offset, data, sz); + + count_only: + state->buf_user_offset += sz; + return ebt_buf_count(state, sz); +} + +static int ebt_buf_add_pad(struct ebt_entries_buf_state *state, unsigned int sz) +{ + char *b = state->buf_kern_start; + + BUG_ON(b && state->buf_kern_offset > state->buf_kern_len); + + if (b != NULL && sz > 0) + memset(b + state->buf_kern_offset, 0, sz); + /* do not adjust ->buf_user_offset here, we added kernel-side padding */ + return ebt_buf_count(state, sz); +} + +enum compat_mwt { + EBT_COMPAT_MATCH, + EBT_COMPAT_WATCHER, + EBT_COMPAT_TARGET, +}; + +static int compat_mtw_from_user(struct compat_ebt_entry_mwt *mwt, + enum compat_mwt compat_mwt, + struct ebt_entries_buf_state *state, + const unsigned char *base) +{ + char name[EBT_FUNCTION_MAXNAMELEN]; + struct xt_match *match; + struct xt_target *wt; + void *dst = NULL; + int off, pad = 0; + unsigned int size_kern, match_size = mwt->match_size; + + strlcpy(name, mwt->u.name, sizeof(name)); + + if (state->buf_kern_start) + dst = state->buf_kern_start + state->buf_kern_offset; + + switch (compat_mwt) { + case EBT_COMPAT_MATCH: + match = xt_request_find_match(NFPROTO_BRIDGE, name, 0); + if (IS_ERR(match)) + return PTR_ERR(match); + + off = ebt_compat_match_offset(match, match_size); + if (dst) { + if (match->compat_from_user) + match->compat_from_user(dst, mwt->data); + else + memcpy(dst, mwt->data, match_size); + } + + size_kern = match->matchsize; + if (unlikely(size_kern == -1)) + size_kern = match_size; + module_put(match->me); + break; + case EBT_COMPAT_WATCHER: /* fallthrough */ + case EBT_COMPAT_TARGET: + wt = xt_request_find_target(NFPROTO_BRIDGE, name, 0); + if (IS_ERR(wt)) + return PTR_ERR(wt); + off = xt_compat_target_offset(wt); + + if (dst) { + if (wt->compat_from_user) + wt->compat_from_user(dst, mwt->data); + else + memcpy(dst, mwt->data, match_size); + } + + size_kern = wt->targetsize; + module_put(wt->me); + break; + + default: + return -EINVAL; + } + + state->buf_kern_offset += match_size + off; + state->buf_user_offset += match_size; + pad = XT_ALIGN(size_kern) - size_kern; + + if (pad > 0 && dst) { + BUG_ON(state->buf_kern_len <= pad); + BUG_ON(state->buf_kern_offset - (match_size + off) + size_kern > state->buf_kern_len - pad); + memset(dst + size_kern, 0, pad); + } + return off + match_size; +} + +/* + * return size of all matches, watchers or target, including necessary + * alignment and padding. + */ +static int ebt_size_mwt(struct compat_ebt_entry_mwt *match32, + unsigned int size_left, enum compat_mwt type, + struct ebt_entries_buf_state *state, const void *base) +{ + int growth = 0; + char *buf; + + if (size_left == 0) + return 0; + + buf = (char *) match32; + + while (size_left >= sizeof(*match32)) { + struct ebt_entry_match *match_kern; + int ret; + + match_kern = (struct ebt_entry_match *) state->buf_kern_start; + if (match_kern) { + char *tmp; + tmp = state->buf_kern_start + state->buf_kern_offset; + match_kern = (struct ebt_entry_match *) tmp; + } + ret = ebt_buf_add(state, buf, sizeof(*match32)); + if (ret < 0) + return ret; + size_left -= sizeof(*match32); + + /* add padding before match->data (if any) */ + ret = ebt_buf_add_pad(state, ebt_compat_entry_padsize()); + if (ret < 0) + return ret; + + if (match32->match_size > size_left) + return -EINVAL; + + size_left -= match32->match_size; + + ret = compat_mtw_from_user(match32, type, state, base); + if (ret < 0) + return ret; + + BUG_ON(ret < match32->match_size); + growth += ret - match32->match_size; + growth += ebt_compat_entry_padsize(); + + buf += sizeof(*match32); + buf += match32->match_size; + + if (match_kern) + match_kern->match_size = ret; + + WARN_ON(type == EBT_COMPAT_TARGET && size_left); + match32 = (struct compat_ebt_entry_mwt *) buf; + } + + return growth; +} + +/* called for all ebt_entry structures. */ +static int size_entry_mwt(struct ebt_entry *entry, const unsigned char *base, + unsigned int *total, + struct ebt_entries_buf_state *state) +{ + unsigned int i, j, startoff, new_offset = 0; + /* stores match/watchers/targets & offset of next struct ebt_entry: */ + unsigned int offsets[4]; + unsigned int *offsets_update = NULL; + int ret; + char *buf_start; + + if (*total < sizeof(struct ebt_entries)) + return -EINVAL; + + if (!entry->bitmask) { + *total -= sizeof(struct ebt_entries); + return ebt_buf_add(state, entry, sizeof(struct ebt_entries)); + } + if (*total < sizeof(*entry) || entry->next_offset < sizeof(*entry)) + return -EINVAL; + + startoff = state->buf_user_offset; + /* pull in most part of ebt_entry, it does not need to be changed. */ + ret = ebt_buf_add(state, entry, + offsetof(struct ebt_entry, watchers_offset)); + if (ret < 0) + return ret; + + offsets[0] = sizeof(struct ebt_entry); /* matches come first */ + memcpy(&offsets[1], &entry->watchers_offset, + sizeof(offsets) - sizeof(offsets[0])); + + if (state->buf_kern_start) { + buf_start = state->buf_kern_start + state->buf_kern_offset; + offsets_update = (unsigned int *) buf_start; + } + ret = ebt_buf_add(state, &offsets[1], + sizeof(offsets) - sizeof(offsets[0])); + if (ret < 0) + return ret; + buf_start = (char *) entry; + /* + * 0: matches offset, always follows ebt_entry. + * 1: watchers offset, from ebt_entry structure + * 2: target offset, from ebt_entry structure + * 3: next ebt_entry offset, from ebt_entry structure + * + * offsets are relative to beginning of struct ebt_entry (i.e., 0). + */ + for (i = 0, j = 1 ; j < 4 ; j++, i++) { + struct compat_ebt_entry_mwt *match32; + unsigned int size; + char *buf = buf_start; + + buf = buf_start + offsets[i]; + if (offsets[i] > offsets[j]) + return -EINVAL; + + match32 = (struct compat_ebt_entry_mwt *) buf; + size = offsets[j] - offsets[i]; + ret = ebt_size_mwt(match32, size, i, state, base); + if (ret < 0) + return ret; + new_offset += ret; + if (offsets_update && new_offset) { + pr_debug("change offset %d to %d\n", + offsets_update[i], offsets[j] + new_offset); + offsets_update[i] = offsets[j] + new_offset; + } + } + + if (state->buf_kern_start == NULL) { + unsigned int offset = buf_start - (char *) base; + + ret = xt_compat_add_offset(NFPROTO_BRIDGE, offset, new_offset); + if (ret < 0) + return ret; + } + + startoff = state->buf_user_offset - startoff; + + BUG_ON(*total < startoff); + *total -= startoff; + return 0; +} + +/* + * repl->entries_size is the size of the ebt_entry blob in userspace. + * It might need more memory when copied to a 64 bit kernel in case + * userspace is 32-bit. So, first task: find out how much memory is needed. + * + * Called before validation is performed. + */ +static int compat_copy_entries(unsigned char *data, unsigned int size_user, + struct ebt_entries_buf_state *state) +{ + unsigned int size_remaining = size_user; + int ret; + + ret = EBT_ENTRY_ITERATE(data, size_user, size_entry_mwt, data, + &size_remaining, state); + if (ret < 0) + return ret; + + WARN_ON(size_remaining); + return state->buf_kern_offset; +} + + +static int compat_copy_ebt_replace_from_user(struct ebt_replace *repl, + void __user *user, unsigned int len) +{ + struct compat_ebt_replace tmp; + int i; + + if (len < sizeof(tmp)) + return -EINVAL; + + if (copy_from_user(&tmp, user, sizeof(tmp))) + return -EFAULT; + + if (len != sizeof(tmp) + tmp.entries_size) + return -EINVAL; + + if (tmp.entries_size == 0) + return -EINVAL; + + if (tmp.nentries >= ((INT_MAX - sizeof(struct ebt_table_info)) / + NR_CPUS - SMP_CACHE_BYTES) / sizeof(struct ebt_counter)) + return -ENOMEM; + if (tmp.num_counters >= INT_MAX / sizeof(struct ebt_counter)) + return -ENOMEM; + + memcpy(repl, &tmp, offsetof(struct ebt_replace, hook_entry)); + + /* starting with hook_entry, 32 vs. 64 bit structures are different */ + for (i = 0; i < NF_BR_NUMHOOKS; i++) + repl->hook_entry[i] = compat_ptr(tmp.hook_entry[i]); + + repl->num_counters = tmp.num_counters; + repl->counters = compat_ptr(tmp.counters); + repl->entries = compat_ptr(tmp.entries); + return 0; +} + +static int compat_do_replace(struct net *net, void __user *user, + unsigned int len) +{ + int ret, i, countersize, size64; + struct ebt_table_info *newinfo; + struct ebt_replace tmp; + struct ebt_entries_buf_state state; + void *entries_tmp; + + ret = compat_copy_ebt_replace_from_user(&tmp, user, len); + if (ret) { + /* try real handler in case userland supplied needed padding */ + if (ret == -EINVAL && do_replace(net, user, len) == 0) + ret = 0; + return ret; + } + + countersize = COUNTER_OFFSET(tmp.nentries) * nr_cpu_ids; + newinfo = vmalloc(sizeof(*newinfo) + countersize); + if (!newinfo) + return -ENOMEM; + + if (countersize) + memset(newinfo->counters, 0, countersize); + + memset(&state, 0, sizeof(state)); + + newinfo->entries = vmalloc(tmp.entries_size); + if (!newinfo->entries) { + ret = -ENOMEM; + goto free_newinfo; + } + if (copy_from_user( + newinfo->entries, tmp.entries, tmp.entries_size) != 0) { + ret = -EFAULT; + goto free_entries; + } + + entries_tmp = newinfo->entries; + + xt_compat_lock(NFPROTO_BRIDGE); + + xt_compat_init_offsets(NFPROTO_BRIDGE, tmp.nentries); + ret = compat_copy_entries(entries_tmp, tmp.entries_size, &state); + if (ret < 0) + goto out_unlock; + + pr_debug("tmp.entries_size %d, kern off %d, user off %d delta %d\n", + tmp.entries_size, state.buf_kern_offset, state.buf_user_offset, + xt_compat_calc_jump(NFPROTO_BRIDGE, tmp.entries_size)); + + size64 = ret; + newinfo->entries = vmalloc(size64); + if (!newinfo->entries) { + vfree(entries_tmp); + ret = -ENOMEM; + goto out_unlock; + } + + memset(&state, 0, sizeof(state)); + state.buf_kern_start = newinfo->entries; + state.buf_kern_len = size64; + + ret = compat_copy_entries(entries_tmp, tmp.entries_size, &state); + BUG_ON(ret < 0); /* parses same data again */ + + vfree(entries_tmp); + tmp.entries_size = size64; + + for (i = 0; i < NF_BR_NUMHOOKS; i++) { + char __user *usrptr; + if (tmp.hook_entry[i]) { + unsigned int delta; + usrptr = (char __user *) tmp.hook_entry[i]; + delta = usrptr - tmp.entries; + usrptr += xt_compat_calc_jump(NFPROTO_BRIDGE, delta); + tmp.hook_entry[i] = (struct ebt_entries __user *)usrptr; + } + } + + xt_compat_flush_offsets(NFPROTO_BRIDGE); + xt_compat_unlock(NFPROTO_BRIDGE); + + ret = do_replace_finish(net, &tmp, newinfo); + if (ret == 0) + return ret; +free_entries: + vfree(newinfo->entries); +free_newinfo: + vfree(newinfo); + return ret; +out_unlock: + xt_compat_flush_offsets(NFPROTO_BRIDGE); + xt_compat_unlock(NFPROTO_BRIDGE); + goto free_entries; +} + +static int compat_update_counters(struct net *net, void __user *user, + unsigned int len) +{ + struct compat_ebt_replace hlp; + + if (copy_from_user(&hlp, user, sizeof(hlp))) + return -EFAULT; + + /* try real handler in case userland supplied needed padding */ + if (len != sizeof(hlp) + hlp.num_counters * sizeof(struct ebt_counter)) + return update_counters(net, user, len); + + return do_update_counters(net, hlp.name, compat_ptr(hlp.counters), + hlp.num_counters, user, len); +} + +static int compat_do_ebt_set_ctl(struct sock *sk, + int cmd, void __user *user, unsigned int len) +{ + int ret; + + if (!capable(CAP_NET_ADMIN)) + return -EPERM; + + switch (cmd) { + case EBT_SO_SET_ENTRIES: + ret = compat_do_replace(sock_net(sk), user, len); + break; + case EBT_SO_SET_COUNTERS: + ret = compat_update_counters(sock_net(sk), user, len); + break; + default: + ret = -EINVAL; + } + return ret; +} + +static int compat_do_ebt_get_ctl(struct sock *sk, int cmd, + void __user *user, int *len) +{ + int ret; + struct compat_ebt_replace tmp; + struct ebt_table *t; + + if (!capable(CAP_NET_ADMIN)) + return -EPERM; + + /* try real handler in case userland supplied needed padding */ + if ((cmd == EBT_SO_GET_INFO || + cmd == EBT_SO_GET_INIT_INFO) && *len != sizeof(tmp)) + return do_ebt_get_ctl(sk, cmd, user, len); + + if (copy_from_user(&tmp, user, sizeof(tmp))) + return -EFAULT; + + t = find_table_lock(sock_net(sk), tmp.name, &ret, &ebt_mutex); + if (!t) + return ret; + + xt_compat_lock(NFPROTO_BRIDGE); + switch (cmd) { + case EBT_SO_GET_INFO: + tmp.nentries = t->private->nentries; + ret = compat_table_info(t->private, &tmp); + if (ret) + goto out; + tmp.valid_hooks = t->valid_hooks; + + if (copy_to_user(user, &tmp, *len) != 0) { + ret = -EFAULT; + break; + } + ret = 0; + break; + case EBT_SO_GET_INIT_INFO: + tmp.nentries = t->table->nentries; + tmp.entries_size = t->table->entries_size; + tmp.valid_hooks = t->table->valid_hooks; + + if (copy_to_user(user, &tmp, *len) != 0) { + ret = -EFAULT; + break; + } + ret = 0; + break; + case EBT_SO_GET_ENTRIES: + case EBT_SO_GET_INIT_ENTRIES: + /* + * try real handler first in case of userland-side padding. + * in case we are dealing with an 'ordinary' 32 bit binary + * without 64bit compatibility padding, this will fail right + * after copy_from_user when the *len argument is validated. + * + * the compat_ variant needs to do one pass over the kernel + * data set to adjust for size differences before it the check. + */ + if (copy_everything_to_user(t, user, len, cmd) == 0) + ret = 0; + else + ret = compat_copy_everything_to_user(t, user, len, cmd); + break; + default: + ret = -EINVAL; + } + out: + xt_compat_flush_offsets(NFPROTO_BRIDGE); + xt_compat_unlock(NFPROTO_BRIDGE); + mutex_unlock(&ebt_mutex); + return ret; +} +#endif + +static struct nf_sockopt_ops ebt_sockopts = +{ + .pf = PF_INET, + .set_optmin = EBT_BASE_CTL, + .set_optmax = EBT_SO_SET_MAX + 1, + .set = do_ebt_set_ctl, +#ifdef CONFIG_COMPAT + .compat_set = compat_do_ebt_set_ctl, +#endif + .get_optmin = EBT_BASE_CTL, + .get_optmax = EBT_SO_GET_MAX + 1, + .get = do_ebt_get_ctl, +#ifdef CONFIG_COMPAT + .compat_get = compat_do_ebt_get_ctl, +#endif + .owner = THIS_MODULE, +}; + +static int __init ebtables_init(void) +{ + int ret; + + ret = xt_register_target(&ebt_standard_target); + if (ret < 0) + return ret; + ret = nf_register_sockopt(&ebt_sockopts); + if (ret < 0) { + xt_unregister_target(&ebt_standard_target); + return ret; + } + + printk(KERN_INFO "Ebtables v2.0 registered\n"); + return 0; +} + +static void __exit ebtables_fini(void) +{ + nf_unregister_sockopt(&ebt_sockopts); + xt_unregister_target(&ebt_standard_target); + printk(KERN_INFO "Ebtables v2.0 unregistered\n"); +} + +EXPORT_SYMBOL(ebt_register_table); +EXPORT_SYMBOL(ebt_unregister_table); +EXPORT_SYMBOL(ebt_do_table); +module_init(ebtables_init); +module_exit(ebtables_fini); +MODULE_LICENSE("GPL"); |