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Diffstat (limited to 'drivers/char/tty_audit.c')
-rw-r--r--drivers/char/tty_audit.c358
1 files changed, 0 insertions, 358 deletions
diff --git a/drivers/char/tty_audit.c b/drivers/char/tty_audit.c
deleted file mode 100644
index f64582b0f62..00000000000
--- a/drivers/char/tty_audit.c
+++ /dev/null
@@ -1,358 +0,0 @@
-/*
- * Creating audit events from TTY input.
- *
- * Copyright (C) 2007 Red Hat, Inc. All rights reserved. This copyrighted
- * material is made available to anyone wishing to use, modify, copy, or
- * redistribute it subject to the terms and conditions of the GNU General
- * Public License v.2.
- *
- * Authors: Miloslav Trmac <mitr@redhat.com>
- */
-
-#include <linux/audit.h>
-#include <linux/slab.h>
-#include <linux/tty.h>
-
-struct tty_audit_buf {
- atomic_t count;
- struct mutex mutex; /* Protects all data below */
- int major, minor; /* The TTY which the data is from */
- unsigned icanon:1;
- size_t valid;
- unsigned char *data; /* Allocated size N_TTY_BUF_SIZE */
-};
-
-static struct tty_audit_buf *tty_audit_buf_alloc(int major, int minor,
- int icanon)
-{
- struct tty_audit_buf *buf;
-
- buf = kmalloc(sizeof(*buf), GFP_KERNEL);
- if (!buf)
- goto err;
- buf->data = kmalloc(N_TTY_BUF_SIZE, GFP_KERNEL);
- if (!buf->data)
- goto err_buf;
- atomic_set(&buf->count, 1);
- mutex_init(&buf->mutex);
- buf->major = major;
- buf->minor = minor;
- buf->icanon = icanon;
- buf->valid = 0;
- return buf;
-
-err_buf:
- kfree(buf);
-err:
- return NULL;
-}
-
-static void tty_audit_buf_free(struct tty_audit_buf *buf)
-{
- WARN_ON(buf->valid != 0);
- kfree(buf->data);
- kfree(buf);
-}
-
-static void tty_audit_buf_put(struct tty_audit_buf *buf)
-{
- if (atomic_dec_and_test(&buf->count))
- tty_audit_buf_free(buf);
-}
-
-static void tty_audit_log(const char *description, struct task_struct *tsk,
- uid_t loginuid, unsigned sessionid, int major,
- int minor, unsigned char *data, size_t size)
-{
- struct audit_buffer *ab;
-
- ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_TTY);
- if (ab) {
- char name[sizeof(tsk->comm)];
- uid_t uid = task_uid(tsk);
-
- audit_log_format(ab, "%s pid=%u uid=%u auid=%u ses=%u "
- "major=%d minor=%d comm=", description,
- tsk->pid, uid, loginuid, sessionid,
- major, minor);
- get_task_comm(name, tsk);
- audit_log_untrustedstring(ab, name);
- audit_log_format(ab, " data=");
- audit_log_n_hex(ab, data, size);
- audit_log_end(ab);
- }
-}
-
-/**
- * tty_audit_buf_push - Push buffered data out
- *
- * Generate an audit message from the contents of @buf, which is owned by
- * @tsk with @loginuid. @buf->mutex must be locked.
- */
-static void tty_audit_buf_push(struct task_struct *tsk, uid_t loginuid,
- unsigned int sessionid,
- struct tty_audit_buf *buf)
-{
- if (buf->valid == 0)
- return;
- if (audit_enabled == 0)
- return;
- tty_audit_log("tty", tsk, loginuid, sessionid, buf->major, buf->minor,
- buf->data, buf->valid);
- buf->valid = 0;
-}
-
-/**
- * tty_audit_buf_push_current - Push buffered data out
- *
- * Generate an audit message from the contents of @buf, which is owned by
- * the current task. @buf->mutex must be locked.
- */
-static void tty_audit_buf_push_current(struct tty_audit_buf *buf)
-{
- uid_t auid = audit_get_loginuid(current);
- unsigned int sessionid = audit_get_sessionid(current);
- tty_audit_buf_push(current, auid, sessionid, buf);
-}
-
-/**
- * tty_audit_exit - Handle a task exit
- *
- * Make sure all buffered data is written out and deallocate the buffer.
- * Only needs to be called if current->signal->tty_audit_buf != %NULL.
- */
-void tty_audit_exit(void)
-{
- struct tty_audit_buf *buf;
-
- spin_lock_irq(&current->sighand->siglock);
- buf = current->signal->tty_audit_buf;
- current->signal->tty_audit_buf = NULL;
- spin_unlock_irq(&current->sighand->siglock);
- if (!buf)
- return;
-
- mutex_lock(&buf->mutex);
- tty_audit_buf_push_current(buf);
- mutex_unlock(&buf->mutex);
-
- tty_audit_buf_put(buf);
-}
-
-/**
- * tty_audit_fork - Copy TTY audit state for a new task
- *
- * Set up TTY audit state in @sig from current. @sig needs no locking.
- */
-void tty_audit_fork(struct signal_struct *sig)
-{
- spin_lock_irq(&current->sighand->siglock);
- sig->audit_tty = current->signal->audit_tty;
- spin_unlock_irq(&current->sighand->siglock);
-}
-
-/**
- * tty_audit_tiocsti - Log TIOCSTI
- */
-void tty_audit_tiocsti(struct tty_struct *tty, char ch)
-{
- struct tty_audit_buf *buf;
- int major, minor, should_audit;
-
- spin_lock_irq(&current->sighand->siglock);
- should_audit = current->signal->audit_tty;
- buf = current->signal->tty_audit_buf;
- if (buf)
- atomic_inc(&buf->count);
- spin_unlock_irq(&current->sighand->siglock);
-
- major = tty->driver->major;
- minor = tty->driver->minor_start + tty->index;
- if (buf) {
- mutex_lock(&buf->mutex);
- if (buf->major == major && buf->minor == minor)
- tty_audit_buf_push_current(buf);
- mutex_unlock(&buf->mutex);
- tty_audit_buf_put(buf);
- }
-
- if (should_audit && audit_enabled) {
- uid_t auid;
- unsigned int sessionid;
-
- auid = audit_get_loginuid(current);
- sessionid = audit_get_sessionid(current);
- tty_audit_log("ioctl=TIOCSTI", current, auid, sessionid, major,
- minor, &ch, 1);
- }
-}
-
-/**
- * tty_audit_push_task - Flush task's pending audit data
- * @tsk: task pointer
- * @loginuid: sender login uid
- * @sessionid: sender session id
- *
- * Called with a ref on @tsk held. Try to lock sighand and get a
- * reference to the tty audit buffer if available.
- * Flush the buffer or return an appropriate error code.
- */
-int tty_audit_push_task(struct task_struct *tsk, uid_t loginuid, u32 sessionid)
-{
- struct tty_audit_buf *buf = ERR_PTR(-EPERM);
- unsigned long flags;
-
- if (!lock_task_sighand(tsk, &flags))
- return -ESRCH;
-
- if (tsk->signal->audit_tty) {
- buf = tsk->signal->tty_audit_buf;
- if (buf)
- atomic_inc(&buf->count);
- }
- unlock_task_sighand(tsk, &flags);
-
- /*
- * Return 0 when signal->audit_tty set
- * but tsk->signal->tty_audit_buf == NULL.
- */
- if (!buf || IS_ERR(buf))
- return PTR_ERR(buf);
-
- mutex_lock(&buf->mutex);
- tty_audit_buf_push(tsk, loginuid, sessionid, buf);
- mutex_unlock(&buf->mutex);
-
- tty_audit_buf_put(buf);
- return 0;
-}
-
-/**
- * tty_audit_buf_get - Get an audit buffer.
- *
- * Get an audit buffer for @tty, allocate it if necessary. Return %NULL
- * if TTY auditing is disabled or out of memory. Otherwise, return a new
- * reference to the buffer.
- */
-static struct tty_audit_buf *tty_audit_buf_get(struct tty_struct *tty)
-{
- struct tty_audit_buf *buf, *buf2;
-
- buf = NULL;
- buf2 = NULL;
- spin_lock_irq(&current->sighand->siglock);
- if (likely(!current->signal->audit_tty))
- goto out;
- buf = current->signal->tty_audit_buf;
- if (buf) {
- atomic_inc(&buf->count);
- goto out;
- }
- spin_unlock_irq(&current->sighand->siglock);
-
- buf2 = tty_audit_buf_alloc(tty->driver->major,
- tty->driver->minor_start + tty->index,
- tty->icanon);
- if (buf2 == NULL) {
- audit_log_lost("out of memory in TTY auditing");
- return NULL;
- }
-
- spin_lock_irq(&current->sighand->siglock);
- if (!current->signal->audit_tty)
- goto out;
- buf = current->signal->tty_audit_buf;
- if (!buf) {
- current->signal->tty_audit_buf = buf2;
- buf = buf2;
- buf2 = NULL;
- }
- atomic_inc(&buf->count);
- /* Fall through */
- out:
- spin_unlock_irq(&current->sighand->siglock);
- if (buf2)
- tty_audit_buf_free(buf2);
- return buf;
-}
-
-/**
- * tty_audit_add_data - Add data for TTY auditing.
- *
- * Audit @data of @size from @tty, if necessary.
- */
-void tty_audit_add_data(struct tty_struct *tty, unsigned char *data,
- size_t size)
-{
- struct tty_audit_buf *buf;
- int major, minor;
-
- if (unlikely(size == 0))
- return;
-
- if (tty->driver->type == TTY_DRIVER_TYPE_PTY
- && tty->driver->subtype == PTY_TYPE_MASTER)
- return;
-
- buf = tty_audit_buf_get(tty);
- if (!buf)
- return;
-
- mutex_lock(&buf->mutex);
- major = tty->driver->major;
- minor = tty->driver->minor_start + tty->index;
- if (buf->major != major || buf->minor != minor
- || buf->icanon != tty->icanon) {
- tty_audit_buf_push_current(buf);
- buf->major = major;
- buf->minor = minor;
- buf->icanon = tty->icanon;
- }
- do {
- size_t run;
-
- run = N_TTY_BUF_SIZE - buf->valid;
- if (run > size)
- run = size;
- memcpy(buf->data + buf->valid, data, run);
- buf->valid += run;
- data += run;
- size -= run;
- if (buf->valid == N_TTY_BUF_SIZE)
- tty_audit_buf_push_current(buf);
- } while (size != 0);
- mutex_unlock(&buf->mutex);
- tty_audit_buf_put(buf);
-}
-
-/**
- * tty_audit_push - Push buffered data out
- *
- * Make sure no audit data is pending for @tty on the current process.
- */
-void tty_audit_push(struct tty_struct *tty)
-{
- struct tty_audit_buf *buf;
-
- spin_lock_irq(&current->sighand->siglock);
- if (likely(!current->signal->audit_tty)) {
- spin_unlock_irq(&current->sighand->siglock);
- return;
- }
- buf = current->signal->tty_audit_buf;
- if (buf)
- atomic_inc(&buf->count);
- spin_unlock_irq(&current->sighand->siglock);
-
- if (buf) {
- int major, minor;
-
- major = tty->driver->major;
- minor = tty->driver->minor_start + tty->index;
- mutex_lock(&buf->mutex);
- if (buf->major == major && buf->minor == minor)
- tty_audit_buf_push_current(buf);
- mutex_unlock(&buf->mutex);
- tty_audit_buf_put(buf);
- }
-}
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