diff options
Diffstat (limited to 'net/nfc/llcp/commands.c')
-rw-r--r-- | net/nfc/llcp/commands.c | 530 |
1 files changed, 530 insertions, 0 deletions
diff --git a/net/nfc/llcp/commands.c b/net/nfc/llcp/commands.c new file mode 100644 index 00000000..ef10ffcb --- /dev/null +++ b/net/nfc/llcp/commands.c @@ -0,0 +1,530 @@ +/* + * Copyright (C) 2011 Intel Corporation. All rights reserved. + * + * 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. + */ + +#define pr_fmt(fmt) "llcp: %s: " fmt, __func__ + +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/nfc.h> + +#include <net/nfc/nfc.h> + +#include "../nfc.h" +#include "llcp.h" + +static u8 llcp_tlv_length[LLCP_TLV_MAX] = { + 0, + 1, /* VERSION */ + 2, /* MIUX */ + 2, /* WKS */ + 1, /* LTO */ + 1, /* RW */ + 0, /* SN */ + 1, /* OPT */ + 0, /* SDREQ */ + 2, /* SDRES */ + +}; + +static u8 llcp_tlv8(u8 *tlv, u8 type) +{ + if (tlv[0] != type || tlv[1] != llcp_tlv_length[tlv[0]]) + return 0; + + return tlv[2]; +} + +static u8 llcp_tlv16(u8 *tlv, u8 type) +{ + if (tlv[0] != type || tlv[1] != llcp_tlv_length[tlv[0]]) + return 0; + + return be16_to_cpu(*((__be16 *)(tlv + 2))); +} + + +static u8 llcp_tlv_version(u8 *tlv) +{ + return llcp_tlv8(tlv, LLCP_TLV_VERSION); +} + +static u16 llcp_tlv_miux(u8 *tlv) +{ + return llcp_tlv16(tlv, LLCP_TLV_MIUX) & 0x7f; +} + +static u16 llcp_tlv_wks(u8 *tlv) +{ + return llcp_tlv16(tlv, LLCP_TLV_WKS); +} + +static u16 llcp_tlv_lto(u8 *tlv) +{ + return llcp_tlv8(tlv, LLCP_TLV_LTO); +} + +static u8 llcp_tlv_opt(u8 *tlv) +{ + return llcp_tlv8(tlv, LLCP_TLV_OPT); +} + +static u8 llcp_tlv_rw(u8 *tlv) +{ + return llcp_tlv8(tlv, LLCP_TLV_RW) & 0xf; +} + +u8 *nfc_llcp_build_tlv(u8 type, u8 *value, u8 value_length, u8 *tlv_length) +{ + u8 *tlv, length; + + pr_debug("type %d\n", type); + + if (type >= LLCP_TLV_MAX) + return NULL; + + length = llcp_tlv_length[type]; + if (length == 0 && value_length == 0) + return NULL; + else + length = value_length; + + *tlv_length = 2 + length; + tlv = kzalloc(2 + length, GFP_KERNEL); + if (tlv == NULL) + return tlv; + + tlv[0] = type; + tlv[1] = length; + memcpy(tlv + 2, value, length); + + return tlv; +} + +int nfc_llcp_parse_tlv(struct nfc_llcp_local *local, + u8 *tlv_array, u16 tlv_array_len) +{ + u8 *tlv = tlv_array, type, length, offset = 0; + + pr_debug("TLV array length %d\n", tlv_array_len); + + if (local == NULL) + return -ENODEV; + + while (offset < tlv_array_len) { + type = tlv[0]; + length = tlv[1]; + + pr_debug("type 0x%x length %d\n", type, length); + + switch (type) { + case LLCP_TLV_VERSION: + local->remote_version = llcp_tlv_version(tlv); + break; + case LLCP_TLV_MIUX: + local->remote_miu = llcp_tlv_miux(tlv) + 128; + break; + case LLCP_TLV_WKS: + local->remote_wks = llcp_tlv_wks(tlv); + break; + case LLCP_TLV_LTO: + local->remote_lto = llcp_tlv_lto(tlv) * 10; + break; + case LLCP_TLV_OPT: + local->remote_opt = llcp_tlv_opt(tlv); + break; + case LLCP_TLV_RW: + local->remote_rw = llcp_tlv_rw(tlv); + break; + case LLCP_TLV_SN: + break; + default: + pr_err("Invalid gt tlv value 0x%x\n", type); + break; + } + + offset += length + 2; + tlv += length + 2; + } + + pr_debug("version 0x%x miu %d lto %d opt 0x%x wks 0x%x rw %d\n", + local->remote_version, local->remote_miu, + local->remote_lto, local->remote_opt, + local->remote_wks, local->remote_rw); + + return 0; +} + +static struct sk_buff *llcp_add_header(struct sk_buff *pdu, + u8 dsap, u8 ssap, u8 ptype) +{ + u8 header[2]; + + pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap); + + header[0] = (u8)((dsap << 2) | (ptype >> 2)); + header[1] = (u8)((ptype << 6) | ssap); + + pr_debug("header 0x%x 0x%x\n", header[0], header[1]); + + memcpy(skb_put(pdu, LLCP_HEADER_SIZE), header, LLCP_HEADER_SIZE); + + return pdu; +} + +static struct sk_buff *llcp_add_tlv(struct sk_buff *pdu, u8 *tlv, + u8 tlv_length) +{ + /* XXX Add an skb length check */ + + if (tlv == NULL) + return NULL; + + memcpy(skb_put(pdu, tlv_length), tlv, tlv_length); + + return pdu; +} + +static struct sk_buff *llcp_allocate_pdu(struct nfc_llcp_sock *sock, + u8 cmd, u16 size) +{ + struct sk_buff *skb; + int err; + + if (sock->ssap == 0) + return NULL; + + skb = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT, + size + LLCP_HEADER_SIZE, &err); + if (skb == NULL) { + pr_err("Could not allocate PDU\n"); + return NULL; + } + + skb = llcp_add_header(skb, sock->dsap, sock->ssap, cmd); + + return skb; +} + +int nfc_llcp_disconnect(struct nfc_llcp_sock *sock) +{ + struct sk_buff *skb; + struct nfc_dev *dev; + struct nfc_llcp_local *local; + u16 size = 0; + + pr_debug("Sending DISC\n"); + + local = sock->local; + if (local == NULL) + return -ENODEV; + + dev = sock->dev; + if (dev == NULL) + return -ENODEV; + + size += LLCP_HEADER_SIZE; + size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE; + + skb = alloc_skb(size, GFP_ATOMIC); + if (skb == NULL) + return -ENOMEM; + + skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE); + + skb = llcp_add_header(skb, sock->ssap, sock->dsap, LLCP_PDU_DISC); + + skb_queue_tail(&local->tx_queue, skb); + + return 0; +} + +int nfc_llcp_send_symm(struct nfc_dev *dev) +{ + struct sk_buff *skb; + struct nfc_llcp_local *local; + u16 size = 0; + + pr_debug("Sending SYMM\n"); + + local = nfc_llcp_find_local(dev); + if (local == NULL) + return -ENODEV; + + size += LLCP_HEADER_SIZE; + size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE; + + skb = alloc_skb(size, GFP_KERNEL); + if (skb == NULL) + return -ENOMEM; + + skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE); + + skb = llcp_add_header(skb, 0, 0, LLCP_PDU_SYMM); + + return nfc_data_exchange(dev, local->target_idx, skb, + nfc_llcp_recv, local); +} + +int nfc_llcp_send_connect(struct nfc_llcp_sock *sock) +{ + struct nfc_llcp_local *local; + struct sk_buff *skb; + u8 *service_name_tlv = NULL, service_name_tlv_length; + u8 *miux_tlv = NULL, miux_tlv_length; + u8 *rw_tlv = NULL, rw_tlv_length, rw; + __be16 miux; + int err; + u16 size = 0; + + pr_debug("Sending CONNECT\n"); + + local = sock->local; + if (local == NULL) + return -ENODEV; + + if (sock->service_name != NULL) { + service_name_tlv = nfc_llcp_build_tlv(LLCP_TLV_SN, + sock->service_name, + sock->service_name_len, + &service_name_tlv_length); + size += service_name_tlv_length; + } + + miux = cpu_to_be16(LLCP_MAX_MIUX); + miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0, + &miux_tlv_length); + size += miux_tlv_length; + + rw = LLCP_MAX_RW; + rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length); + size += rw_tlv_length; + + pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len); + + skb = llcp_allocate_pdu(sock, LLCP_PDU_CONNECT, size); + if (skb == NULL) { + err = -ENOMEM; + goto error_tlv; + } + + if (service_name_tlv != NULL) + skb = llcp_add_tlv(skb, service_name_tlv, + service_name_tlv_length); + + skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length); + skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length); + + skb_queue_tail(&local->tx_queue, skb); + + return 0; + +error_tlv: + pr_err("error %d\n", err); + + kfree(service_name_tlv); + kfree(miux_tlv); + kfree(rw_tlv); + + return err; +} + +int nfc_llcp_send_cc(struct nfc_llcp_sock *sock) +{ + struct nfc_llcp_local *local; + struct sk_buff *skb; + u8 *miux_tlv = NULL, miux_tlv_length; + u8 *rw_tlv = NULL, rw_tlv_length, rw; + __be16 miux; + int err; + u16 size = 0; + + pr_debug("Sending CC\n"); + + local = sock->local; + if (local == NULL) + return -ENODEV; + + miux = cpu_to_be16(LLCP_MAX_MIUX); + miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0, + &miux_tlv_length); + size += miux_tlv_length; + + rw = LLCP_MAX_RW; + rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length); + size += rw_tlv_length; + + skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, size); + if (skb == NULL) { + err = -ENOMEM; + goto error_tlv; + } + + skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length); + skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length); + + skb_queue_tail(&local->tx_queue, skb); + + return 0; + +error_tlv: + pr_err("error %d\n", err); + + kfree(miux_tlv); + kfree(rw_tlv); + + return err; +} + +int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason) +{ + struct sk_buff *skb; + struct nfc_dev *dev; + u16 size = 1; /* Reason code */ + + pr_debug("Sending DM reason 0x%x\n", reason); + + if (local == NULL) + return -ENODEV; + + dev = local->dev; + if (dev == NULL) + return -ENODEV; + + size += LLCP_HEADER_SIZE; + size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE; + + skb = alloc_skb(size, GFP_KERNEL); + if (skb == NULL) + return -ENOMEM; + + skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE); + + skb = llcp_add_header(skb, ssap, dsap, LLCP_PDU_DM); + + memcpy(skb_put(skb, 1), &reason, 1); + + skb_queue_head(&local->tx_queue, skb); + + return 0; +} + +int nfc_llcp_send_disconnect(struct nfc_llcp_sock *sock) +{ + struct sk_buff *skb; + struct nfc_llcp_local *local; + + pr_debug("Send DISC\n"); + + local = sock->local; + if (local == NULL) + return -ENODEV; + + skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0); + if (skb == NULL) + return -ENOMEM; + + skb_queue_head(&local->tx_queue, skb); + + return 0; +} + +int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock, + struct msghdr *msg, size_t len) +{ + struct sk_buff *pdu; + struct sock *sk = &sock->sk; + struct nfc_llcp_local *local; + size_t frag_len = 0, remaining_len; + u8 *msg_data, *msg_ptr; + + pr_debug("Send I frame len %zd\n", len); + + local = sock->local; + if (local == NULL) + return -ENODEV; + + msg_data = kzalloc(len, GFP_KERNEL); + if (msg_data == NULL) + return -ENOMEM; + + if (memcpy_fromiovec(msg_data, msg->msg_iov, len)) { + kfree(msg_data); + return -EFAULT; + } + + remaining_len = len; + msg_ptr = msg_data; + + while (remaining_len > 0) { + + frag_len = min_t(size_t, local->remote_miu, remaining_len); + + pr_debug("Fragment %zd bytes remaining %zd", + frag_len, remaining_len); + + pdu = llcp_allocate_pdu(sock, LLCP_PDU_I, + frag_len + LLCP_SEQUENCE_SIZE); + if (pdu == NULL) + return -ENOMEM; + + skb_put(pdu, LLCP_SEQUENCE_SIZE); + + memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len); + + skb_queue_head(&sock->tx_queue, pdu); + + lock_sock(sk); + + nfc_llcp_queue_i_frames(sock); + + release_sock(sk); + + remaining_len -= frag_len; + msg_ptr += frag_len; + } + + kfree(msg_data); + + return 0; +} + +int nfc_llcp_send_rr(struct nfc_llcp_sock *sock) +{ + struct sk_buff *skb; + struct nfc_llcp_local *local; + + pr_debug("Send rr nr %d\n", sock->recv_n); + + local = sock->local; + if (local == NULL) + return -ENODEV; + + skb = llcp_allocate_pdu(sock, LLCP_PDU_RR, LLCP_SEQUENCE_SIZE); + if (skb == NULL) + return -ENOMEM; + + skb_put(skb, LLCP_SEQUENCE_SIZE); + + skb->data[2] = sock->recv_n % 16; + + skb_queue_head(&local->tx_queue, skb); + + return 0; +} |