diff options
Diffstat (limited to 'ANDROID_3.4.5/drivers/connector')
| -rw-r--r-- | ANDROID_3.4.5/drivers/connector/Kconfig | 22 | ||||
| -rw-r--r-- | ANDROID_3.4.5/drivers/connector/Makefile | 4 | ||||
| -rw-r--r-- | ANDROID_3.4.5/drivers/connector/cn_proc.c | 338 | ||||
| -rw-r--r-- | ANDROID_3.4.5/drivers/connector/cn_queue.c | 159 | ||||
| -rw-r--r-- | ANDROID_3.4.5/drivers/connector/connector.c | 292 |
5 files changed, 815 insertions, 0 deletions
diff --git a/ANDROID_3.4.5/drivers/connector/Kconfig b/ANDROID_3.4.5/drivers/connector/Kconfig new file mode 100644 index 00000000..6e6730f9 --- /dev/null +++ b/ANDROID_3.4.5/drivers/connector/Kconfig @@ -0,0 +1,22 @@ + +menuconfig CONNECTOR + tristate "Connector - unified userspace <-> kernelspace linker" + depends on NET + ---help--- + This is unified userspace <-> kernelspace connector working on top + of the netlink socket protocol. + + Connector support can also be built as a module. If so, the module + will be called cn. + +if CONNECTOR + +config PROC_EVENTS + boolean "Report process events to userspace" + depends on CONNECTOR=y + default y + ---help--- + Provide a connector that reports process events to userspace. Send + events such as fork, exec, id change (uid, gid, suid, etc), and exit. + +endif # CONNECTOR diff --git a/ANDROID_3.4.5/drivers/connector/Makefile b/ANDROID_3.4.5/drivers/connector/Makefile new file mode 100644 index 00000000..1f255e46 --- /dev/null +++ b/ANDROID_3.4.5/drivers/connector/Makefile @@ -0,0 +1,4 @@ +obj-$(CONFIG_CONNECTOR) += cn.o +obj-$(CONFIG_PROC_EVENTS) += cn_proc.o + +cn-y += cn_queue.o connector.o diff --git a/ANDROID_3.4.5/drivers/connector/cn_proc.c b/ANDROID_3.4.5/drivers/connector/cn_proc.c new file mode 100644 index 00000000..77e1e6cd --- /dev/null +++ b/ANDROID_3.4.5/drivers/connector/cn_proc.c @@ -0,0 +1,338 @@ +/* + * cn_proc.c - process events connector + * + * Copyright (C) Matt Helsley, IBM Corp. 2005 + * Based on cn_fork.c by Guillaume Thouvenin <guillaume.thouvenin@bull.net> + * Original copyright notice follows: + * Copyright (C) 2005 BULL SA. + * + * + * 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/module.h> +#include <linux/kernel.h> +#include <linux/ktime.h> +#include <linux/init.h> +#include <linux/connector.h> +#include <linux/gfp.h> +#include <linux/ptrace.h> +#include <linux/atomic.h> + +#include <asm/unaligned.h> + +#include <linux/cn_proc.h> + +#define CN_PROC_MSG_SIZE (sizeof(struct cn_msg) + sizeof(struct proc_event)) + +static atomic_t proc_event_num_listeners = ATOMIC_INIT(0); +static struct cb_id cn_proc_event_id = { CN_IDX_PROC, CN_VAL_PROC }; + +/* proc_event_counts is used as the sequence number of the netlink message */ +static DEFINE_PER_CPU(__u32, proc_event_counts) = { 0 }; + +static inline void get_seq(__u32 *ts, int *cpu) +{ + preempt_disable(); + *ts = __this_cpu_inc_return(proc_event_counts) -1; + *cpu = smp_processor_id(); + preempt_enable(); +} + +void proc_fork_connector(struct task_struct *task) +{ + struct cn_msg *msg; + struct proc_event *ev; + __u8 buffer[CN_PROC_MSG_SIZE]; + struct timespec ts; + struct task_struct *parent; + + if (atomic_read(&proc_event_num_listeners) < 1) + return; + + msg = (struct cn_msg*)buffer; + ev = (struct proc_event*)msg->data; + get_seq(&msg->seq, &ev->cpu); + ktime_get_ts(&ts); /* get high res monotonic timestamp */ + put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns); + ev->what = PROC_EVENT_FORK; + rcu_read_lock(); + parent = rcu_dereference(task->real_parent); + ev->event_data.fork.parent_pid = parent->pid; + ev->event_data.fork.parent_tgid = parent->tgid; + rcu_read_unlock(); + ev->event_data.fork.child_pid = task->pid; + ev->event_data.fork.child_tgid = task->tgid; + + memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); + msg->ack = 0; /* not used */ + msg->len = sizeof(*ev); + /* If cn_netlink_send() failed, the data is not sent */ + cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL); +} + +void proc_exec_connector(struct task_struct *task) +{ + struct cn_msg *msg; + struct proc_event *ev; + struct timespec ts; + __u8 buffer[CN_PROC_MSG_SIZE]; + + if (atomic_read(&proc_event_num_listeners) < 1) + return; + + msg = (struct cn_msg*)buffer; + ev = (struct proc_event*)msg->data; + get_seq(&msg->seq, &ev->cpu); + ktime_get_ts(&ts); /* get high res monotonic timestamp */ + put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns); + ev->what = PROC_EVENT_EXEC; + ev->event_data.exec.process_pid = task->pid; + ev->event_data.exec.process_tgid = task->tgid; + + memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); + msg->ack = 0; /* not used */ + msg->len = sizeof(*ev); + cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL); +} + +void proc_id_connector(struct task_struct *task, int which_id) +{ + struct cn_msg *msg; + struct proc_event *ev; + __u8 buffer[CN_PROC_MSG_SIZE]; + struct timespec ts; + const struct cred *cred; + + if (atomic_read(&proc_event_num_listeners) < 1) + return; + + msg = (struct cn_msg*)buffer; + ev = (struct proc_event*)msg->data; + ev->what = which_id; + ev->event_data.id.process_pid = task->pid; + ev->event_data.id.process_tgid = task->tgid; + rcu_read_lock(); + cred = __task_cred(task); + if (which_id == PROC_EVENT_UID) { + ev->event_data.id.r.ruid = cred->uid; + ev->event_data.id.e.euid = cred->euid; + } else if (which_id == PROC_EVENT_GID) { + ev->event_data.id.r.rgid = cred->gid; + ev->event_data.id.e.egid = cred->egid; + } else { + rcu_read_unlock(); + return; + } + rcu_read_unlock(); + get_seq(&msg->seq, &ev->cpu); + ktime_get_ts(&ts); /* get high res monotonic timestamp */ + put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns); + + memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); + msg->ack = 0; /* not used */ + msg->len = sizeof(*ev); + cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL); +} + +void proc_sid_connector(struct task_struct *task) +{ + struct cn_msg *msg; + struct proc_event *ev; + struct timespec ts; + __u8 buffer[CN_PROC_MSG_SIZE]; + + if (atomic_read(&proc_event_num_listeners) < 1) + return; + + msg = (struct cn_msg *)buffer; + ev = (struct proc_event *)msg->data; + get_seq(&msg->seq, &ev->cpu); + ktime_get_ts(&ts); /* get high res monotonic timestamp */ + put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns); + ev->what = PROC_EVENT_SID; + ev->event_data.sid.process_pid = task->pid; + ev->event_data.sid.process_tgid = task->tgid; + + memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); + msg->ack = 0; /* not used */ + msg->len = sizeof(*ev); + cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL); +} + +void proc_ptrace_connector(struct task_struct *task, int ptrace_id) +{ + struct cn_msg *msg; + struct proc_event *ev; + struct timespec ts; + __u8 buffer[CN_PROC_MSG_SIZE]; + + if (atomic_read(&proc_event_num_listeners) < 1) + return; + + msg = (struct cn_msg *)buffer; + ev = (struct proc_event *)msg->data; + get_seq(&msg->seq, &ev->cpu); + ktime_get_ts(&ts); /* get high res monotonic timestamp */ + put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns); + ev->what = PROC_EVENT_PTRACE; + ev->event_data.ptrace.process_pid = task->pid; + ev->event_data.ptrace.process_tgid = task->tgid; + if (ptrace_id == PTRACE_ATTACH) { + ev->event_data.ptrace.tracer_pid = current->pid; + ev->event_data.ptrace.tracer_tgid = current->tgid; + } else if (ptrace_id == PTRACE_DETACH) { + ev->event_data.ptrace.tracer_pid = 0; + ev->event_data.ptrace.tracer_tgid = 0; + } else + return; + + memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); + msg->ack = 0; /* not used */ + msg->len = sizeof(*ev); + cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL); +} + +void proc_comm_connector(struct task_struct *task) +{ + struct cn_msg *msg; + struct proc_event *ev; + struct timespec ts; + __u8 buffer[CN_PROC_MSG_SIZE]; + + if (atomic_read(&proc_event_num_listeners) < 1) + return; + + msg = (struct cn_msg *)buffer; + ev = (struct proc_event *)msg->data; + get_seq(&msg->seq, &ev->cpu); + ktime_get_ts(&ts); /* get high res monotonic timestamp */ + put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns); + ev->what = PROC_EVENT_COMM; + ev->event_data.comm.process_pid = task->pid; + ev->event_data.comm.process_tgid = task->tgid; + get_task_comm(ev->event_data.comm.comm, task); + + memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); + msg->ack = 0; /* not used */ + msg->len = sizeof(*ev); + cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL); +} + +void proc_exit_connector(struct task_struct *task) +{ + struct cn_msg *msg; + struct proc_event *ev; + __u8 buffer[CN_PROC_MSG_SIZE]; + struct timespec ts; + + if (atomic_read(&proc_event_num_listeners) < 1) + return; + + msg = (struct cn_msg*)buffer; + ev = (struct proc_event*)msg->data; + get_seq(&msg->seq, &ev->cpu); + ktime_get_ts(&ts); /* get high res monotonic timestamp */ + put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns); + ev->what = PROC_EVENT_EXIT; + ev->event_data.exit.process_pid = task->pid; + ev->event_data.exit.process_tgid = task->tgid; + ev->event_data.exit.exit_code = task->exit_code; + ev->event_data.exit.exit_signal = task->exit_signal; + + memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); + msg->ack = 0; /* not used */ + msg->len = sizeof(*ev); + cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL); +} + +/* + * Send an acknowledgement message to userspace + * + * Use 0 for success, EFOO otherwise. + * Note: this is the negative of conventional kernel error + * values because it's not being returned via syscall return + * mechanisms. + */ +static void cn_proc_ack(int err, int rcvd_seq, int rcvd_ack) +{ + struct cn_msg *msg; + struct proc_event *ev; + __u8 buffer[CN_PROC_MSG_SIZE]; + struct timespec ts; + + if (atomic_read(&proc_event_num_listeners) < 1) + return; + + msg = (struct cn_msg*)buffer; + ev = (struct proc_event*)msg->data; + msg->seq = rcvd_seq; + ktime_get_ts(&ts); /* get high res monotonic timestamp */ + put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns); + ev->cpu = -1; + ev->what = PROC_EVENT_NONE; + ev->event_data.ack.err = err; + memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); + msg->ack = rcvd_ack + 1; + msg->len = sizeof(*ev); + cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL); +} + +/** + * cn_proc_mcast_ctl + * @data: message sent from userspace via the connector + */ +static void cn_proc_mcast_ctl(struct cn_msg *msg, + struct netlink_skb_parms *nsp) +{ + enum proc_cn_mcast_op *mc_op = NULL; + int err = 0; + + if (msg->len != sizeof(*mc_op)) + return; + + mc_op = (enum proc_cn_mcast_op*)msg->data; + switch (*mc_op) { + case PROC_CN_MCAST_LISTEN: + atomic_inc(&proc_event_num_listeners); + break; + case PROC_CN_MCAST_IGNORE: + atomic_dec(&proc_event_num_listeners); + break; + default: + err = EINVAL; + break; + } + cn_proc_ack(err, msg->seq, msg->ack); +} + +/* + * cn_proc_init - initialization entry point + * + * Adds the connector callback to the connector driver. + */ +static int __init cn_proc_init(void) +{ + int err; + + if ((err = cn_add_callback(&cn_proc_event_id, "cn_proc", + &cn_proc_mcast_ctl))) { + printk(KERN_WARNING "cn_proc failed to register\n"); + return err; + } + return 0; +} + +module_init(cn_proc_init); diff --git a/ANDROID_3.4.5/drivers/connector/cn_queue.c b/ANDROID_3.4.5/drivers/connector/cn_queue.c new file mode 100644 index 00000000..c42c9d51 --- /dev/null +++ b/ANDROID_3.4.5/drivers/connector/cn_queue.c @@ -0,0 +1,159 @@ +/* + * cn_queue.c + * + * 2004+ Copyright (c) Evgeniy Polyakov <zbr@ioremap.net> + * 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 + * + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/list.h> +#include <linux/workqueue.h> +#include <linux/spinlock.h> +#include <linux/slab.h> +#include <linux/skbuff.h> +#include <linux/suspend.h> +#include <linux/connector.h> +#include <linux/delay.h> + +static struct cn_callback_entry * +cn_queue_alloc_callback_entry(struct cn_queue_dev *dev, const char *name, + struct cb_id *id, + void (*callback)(struct cn_msg *, struct netlink_skb_parms *)) +{ + struct cn_callback_entry *cbq; + + cbq = kzalloc(sizeof(*cbq), GFP_KERNEL); + if (!cbq) { + printk(KERN_ERR "Failed to create new callback queue.\n"); + return NULL; + } + + atomic_set(&cbq->refcnt, 1); + + atomic_inc(&dev->refcnt); + cbq->pdev = dev; + + snprintf(cbq->id.name, sizeof(cbq->id.name), "%s", name); + memcpy(&cbq->id.id, id, sizeof(struct cb_id)); + cbq->callback = callback; + return cbq; +} + +void cn_queue_release_callback(struct cn_callback_entry *cbq) +{ + if (!atomic_dec_and_test(&cbq->refcnt)) + return; + + atomic_dec(&cbq->pdev->refcnt); + kfree(cbq); +} + +int cn_cb_equal(struct cb_id *i1, struct cb_id *i2) +{ + return ((i1->idx == i2->idx) && (i1->val == i2->val)); +} + +int cn_queue_add_callback(struct cn_queue_dev *dev, const char *name, + struct cb_id *id, + void (*callback)(struct cn_msg *, struct netlink_skb_parms *)) +{ + struct cn_callback_entry *cbq, *__cbq; + int found = 0; + + cbq = cn_queue_alloc_callback_entry(dev, name, id, callback); + if (!cbq) + return -ENOMEM; + + spin_lock_bh(&dev->queue_lock); + list_for_each_entry(__cbq, &dev->queue_list, callback_entry) { + if (cn_cb_equal(&__cbq->id.id, id)) { + found = 1; + break; + } + } + if (!found) + list_add_tail(&cbq->callback_entry, &dev->queue_list); + spin_unlock_bh(&dev->queue_lock); + + if (found) { + cn_queue_release_callback(cbq); + return -EINVAL; + } + + cbq->seq = 0; + cbq->group = cbq->id.id.idx; + + return 0; +} + +void cn_queue_del_callback(struct cn_queue_dev *dev, struct cb_id *id) +{ + struct cn_callback_entry *cbq, *n; + int found = 0; + + spin_lock_bh(&dev->queue_lock); + list_for_each_entry_safe(cbq, n, &dev->queue_list, callback_entry) { + if (cn_cb_equal(&cbq->id.id, id)) { + list_del(&cbq->callback_entry); + found = 1; + break; + } + } + spin_unlock_bh(&dev->queue_lock); + + if (found) + cn_queue_release_callback(cbq); +} + +struct cn_queue_dev *cn_queue_alloc_dev(const char *name, struct sock *nls) +{ + struct cn_queue_dev *dev; + + dev = kzalloc(sizeof(*dev), GFP_KERNEL); + if (!dev) + return NULL; + + snprintf(dev->name, sizeof(dev->name), "%s", name); + atomic_set(&dev->refcnt, 0); + INIT_LIST_HEAD(&dev->queue_list); + spin_lock_init(&dev->queue_lock); + + dev->nls = nls; + + return dev; +} + +void cn_queue_free_dev(struct cn_queue_dev *dev) +{ + struct cn_callback_entry *cbq, *n; + + spin_lock_bh(&dev->queue_lock); + list_for_each_entry_safe(cbq, n, &dev->queue_list, callback_entry) + list_del(&cbq->callback_entry); + spin_unlock_bh(&dev->queue_lock); + + while (atomic_read(&dev->refcnt)) { + printk(KERN_INFO "Waiting for %s to become free: refcnt=%d.\n", + dev->name, atomic_read(&dev->refcnt)); + msleep(1000); + } + + kfree(dev); + dev = NULL; +} diff --git a/ANDROID_3.4.5/drivers/connector/connector.c b/ANDROID_3.4.5/drivers/connector/connector.c new file mode 100644 index 00000000..dde6a0fa --- /dev/null +++ b/ANDROID_3.4.5/drivers/connector/connector.c @@ -0,0 +1,292 @@ +/* + * connector.c + * + * 2004+ Copyright (c) Evgeniy Polyakov <zbr@ioremap.net> + * 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 + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/list.h> +#include <linux/skbuff.h> +#include <linux/netlink.h> +#include <linux/moduleparam.h> +#include <linux/connector.h> +#include <linux/slab.h> +#include <linux/mutex.h> +#include <linux/proc_fs.h> +#include <linux/spinlock.h> + +#include <net/sock.h> + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>"); +MODULE_DESCRIPTION("Generic userspace <-> kernelspace connector."); +MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_CONNECTOR); + +static struct cn_dev cdev; + +static int cn_already_initialized; + +/* + * msg->seq and msg->ack are used to determine message genealogy. + * When someone sends message it puts there locally unique sequence + * and random acknowledge numbers. Sequence number may be copied into + * nlmsghdr->nlmsg_seq too. + * + * Sequence number is incremented with each message to be sent. + * + * If we expect reply to our message then the sequence number in + * received message MUST be the same as in original message, and + * acknowledge number MUST be the same + 1. + * + * If we receive a message and its sequence number is not equal to the + * one we are expecting then it is a new message. + * + * If we receive a message and its sequence number is the same as one + * we are expecting but it's acknowledgement number is not equal to + * the acknowledgement number in the original message + 1, then it is + * a new message. + * + */ +int cn_netlink_send(struct cn_msg *msg, u32 __group, gfp_t gfp_mask) +{ + struct cn_callback_entry *__cbq; + unsigned int size; + struct sk_buff *skb; + struct nlmsghdr *nlh; + struct cn_msg *data; + struct cn_dev *dev = &cdev; + u32 group = 0; + int found = 0; + + if (!__group) { + spin_lock_bh(&dev->cbdev->queue_lock); + list_for_each_entry(__cbq, &dev->cbdev->queue_list, + callback_entry) { + if (cn_cb_equal(&__cbq->id.id, &msg->id)) { + found = 1; + group = __cbq->group; + break; + } + } + spin_unlock_bh(&dev->cbdev->queue_lock); + + if (!found) + return -ENODEV; + } else { + group = __group; + } + + if (!netlink_has_listeners(dev->nls, group)) + return -ESRCH; + + size = NLMSG_SPACE(sizeof(*msg) + msg->len); + + skb = alloc_skb(size, gfp_mask); + if (!skb) + return -ENOMEM; + + nlh = NLMSG_PUT(skb, 0, msg->seq, NLMSG_DONE, size - sizeof(*nlh)); + + data = NLMSG_DATA(nlh); + + memcpy(data, msg, sizeof(*data) + msg->len); + + NETLINK_CB(skb).dst_group = group; + + return netlink_broadcast(dev->nls, skb, 0, group, gfp_mask); + +nlmsg_failure: + kfree_skb(skb); + return -EINVAL; +} +EXPORT_SYMBOL_GPL(cn_netlink_send); + +/* + * Callback helper - queues work and setup destructor for given data. + */ +static int cn_call_callback(struct sk_buff *skb) +{ + struct cn_callback_entry *i, *cbq = NULL; + struct cn_dev *dev = &cdev; + struct cn_msg *msg = NLMSG_DATA(nlmsg_hdr(skb)); + struct netlink_skb_parms *nsp = &NETLINK_CB(skb); + int err = -ENODEV; + + spin_lock_bh(&dev->cbdev->queue_lock); + list_for_each_entry(i, &dev->cbdev->queue_list, callback_entry) { + if (cn_cb_equal(&i->id.id, &msg->id)) { + atomic_inc(&i->refcnt); + cbq = i; + break; + } + } + spin_unlock_bh(&dev->cbdev->queue_lock); + + if (cbq != NULL) { + err = 0; + cbq->callback(msg, nsp); + kfree_skb(skb); + cn_queue_release_callback(cbq); + err = 0; + } + + return err; +} + +/* + * Main netlink receiving function. + * + * It checks skb, netlink header and msg sizes, and calls callback helper. + */ +static void cn_rx_skb(struct sk_buff *__skb) +{ + struct nlmsghdr *nlh; + int err; + struct sk_buff *skb; + + skb = skb_get(__skb); + + if (skb->len >= NLMSG_SPACE(0)) { + nlh = nlmsg_hdr(skb); + + if (nlh->nlmsg_len < sizeof(struct cn_msg) || + skb->len < nlh->nlmsg_len || + nlh->nlmsg_len > CONNECTOR_MAX_MSG_SIZE) { + kfree_skb(skb); + return; + } + + err = cn_call_callback(skb); + if (err < 0) + kfree_skb(skb); + } +} + +/* + * Callback add routing - adds callback with given ID and name. + * If there is registered callback with the same ID it will not be added. + * + * May sleep. + */ +int cn_add_callback(struct cb_id *id, const char *name, + void (*callback)(struct cn_msg *, struct netlink_skb_parms *)) +{ + int err; + struct cn_dev *dev = &cdev; + + if (!cn_already_initialized) + return -EAGAIN; + + err = cn_queue_add_callback(dev->cbdev, name, id, callback); + if (err) + return err; + + return 0; +} +EXPORT_SYMBOL_GPL(cn_add_callback); + +/* + * Callback remove routing - removes callback + * with given ID. + * If there is no registered callback with given + * ID nothing happens. + * + * May sleep while waiting for reference counter to become zero. + */ +void cn_del_callback(struct cb_id *id) +{ + struct cn_dev *dev = &cdev; + + cn_queue_del_callback(dev->cbdev, id); +} +EXPORT_SYMBOL_GPL(cn_del_callback); + +static int cn_proc_show(struct seq_file *m, void *v) +{ + struct cn_queue_dev *dev = cdev.cbdev; + struct cn_callback_entry *cbq; + + seq_printf(m, "Name ID\n"); + + spin_lock_bh(&dev->queue_lock); + + list_for_each_entry(cbq, &dev->queue_list, callback_entry) { + seq_printf(m, "%-15s %u:%u\n", + cbq->id.name, + cbq->id.id.idx, + cbq->id.id.val); + } + + spin_unlock_bh(&dev->queue_lock); + + return 0; +} + +static int cn_proc_open(struct inode *inode, struct file *file) +{ + return single_open(file, cn_proc_show, NULL); +} + +static const struct file_operations cn_file_ops = { + .owner = THIS_MODULE, + .open = cn_proc_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release +}; + +static int __devinit cn_init(void) +{ + struct cn_dev *dev = &cdev; + + dev->input = cn_rx_skb; + + dev->nls = netlink_kernel_create(&init_net, NETLINK_CONNECTOR, + CN_NETLINK_USERS + 0xf, + dev->input, NULL, THIS_MODULE); + if (!dev->nls) + return -EIO; + + dev->cbdev = cn_queue_alloc_dev("cqueue", dev->nls); + if (!dev->cbdev) { + netlink_kernel_release(dev->nls); + return -EINVAL; + } + + cn_already_initialized = 1; + + proc_net_fops_create(&init_net, "connector", S_IRUGO, &cn_file_ops); + + return 0; +} + +static void __devexit cn_fini(void) +{ + struct cn_dev *dev = &cdev; + + cn_already_initialized = 0; + + proc_net_remove(&init_net, "connector"); + + cn_queue_free_dev(dev->cbdev); + netlink_kernel_release(dev->nls); +} + +subsys_initcall(cn_init); +module_exit(cn_fini); |