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kernel/audit.c
53.2 KB
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/* audit.c -- Auditing support |
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* Gateway between the kernel (e.g., selinux) and the user-space audit daemon. * System-call specific features have moved to auditsc.c * |
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* Copyright 2003-2007 Red Hat Inc., Durham, North Carolina. |
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* 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 * * Written by Rickard E. (Rik) Faith <faith@redhat.com> * |
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* Goals: 1) Integrate fully with Security Modules. |
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* 2) Minimal run-time overhead: * a) Minimal when syscall auditing is disabled (audit_enable=0). * b) Small when syscall auditing is enabled and no audit record * is generated (defer as much work as possible to record * generation time): * i) context is allocated, * ii) names from getname are stored without a copy, and * iii) inode information stored from path_lookup. * 3) Ability to disable syscall auditing at boot time (audit=0). * 4) Usable by other parts of the kernel (if audit_log* is called, * then a syscall record will be generated automatically for the * current syscall). * 5) Netlink interface to user-space. * 6) Support low-overhead kernel-based filtering to minimize the * information that must be passed to user-space. * |
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* Example user-space utilities: http://people.redhat.com/sgrubb/audit/ |
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*/ |
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
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#include <linux/file.h> |
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#include <linux/init.h> |
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#include <linux/types.h> |
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#include <linux/atomic.h> |
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#include <linux/mm.h> |
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#include <linux/export.h> |
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#include <linux/slab.h> |
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#include <linux/err.h> #include <linux/kthread.h> |
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#include <linux/kernel.h> |
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#include <linux/syscalls.h> |
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#include <linux/audit.h> #include <net/sock.h> |
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#include <net/netlink.h> |
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#include <linux/skbuff.h> |
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#ifdef CONFIG_SECURITY #include <linux/security.h> #endif |
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#include <linux/freezer.h> |
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#include <linux/tty.h> |
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#include <linux/pid_namespace.h> |
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#include <net/netns/generic.h> |
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#include "audit.h" |
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/* No auditing will take place until audit_initialized == AUDIT_INITIALIZED. |
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* (Initialization happens after skb_init is called.) */ |
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#define AUDIT_DISABLED -1 #define AUDIT_UNINITIALIZED 0 #define AUDIT_INITIALIZED 1 |
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static int audit_initialized; |
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#define AUDIT_OFF 0 #define AUDIT_ON 1 #define AUDIT_LOCKED 2 |
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u32 audit_enabled; u32 audit_ever_enabled; |
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EXPORT_SYMBOL_GPL(audit_enabled); |
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/* Default state when kernel boots without any parameters. */ |
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static u32 audit_default; |
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/* If auditing cannot proceed, audit_failure selects what happens. */ |
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static u32 audit_failure = AUDIT_FAIL_PRINTK; |
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/* * If audit records are to be written to the netlink socket, audit_pid |
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* contains the pid of the auditd process and audit_nlk_portid contains * the portid to use to send netlink messages to that process. |
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*/ |
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int audit_pid; |
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static __u32 audit_nlk_portid; |
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/* If audit_rate_limit is non-zero, limit the rate of sending audit records |
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* to that number per second. This prevents DoS attacks, but results in * audit records being dropped. */ |
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static u32 audit_rate_limit; |
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/* Number of outstanding audit_buffers allowed. * When set to zero, this means unlimited. */ |
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static u32 audit_backlog_limit = 64; |
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#define AUDIT_BACKLOG_WAIT_TIME (60 * HZ) |
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static u32 audit_backlog_wait_time_master = AUDIT_BACKLOG_WAIT_TIME; |
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static u32 audit_backlog_wait_time = AUDIT_BACKLOG_WAIT_TIME; static u32 audit_backlog_wait_overflow = 0; |
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/* The identity of the user shutting down the audit system. */ |
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kuid_t audit_sig_uid = INVALID_UID; |
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pid_t audit_sig_pid = -1; |
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u32 audit_sig_sid = 0; |
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/* Records can be lost in several ways: 0) [suppressed in audit_alloc] 1) out of memory in audit_log_start [kmalloc of struct audit_buffer] 2) out of memory in audit_log_move [alloc_skb] 3) suppressed due to audit_rate_limit 4) suppressed due to audit_backlog_limit */ static atomic_t audit_lost = ATOMIC_INIT(0); /* The netlink socket. */ static struct sock *audit_sock; |
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static int audit_net_id; |
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/* Hash for inode-based rules */ struct list_head audit_inode_hash[AUDIT_INODE_BUCKETS]; |
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/* The audit_freelist is a list of pre-allocated audit buffers (if more |
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* than AUDIT_MAXFREE are in use, the audit buffer is freed instead of * being placed on the freelist). */ |
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static DEFINE_SPINLOCK(audit_freelist_lock); |
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static int audit_freelist_count; |
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static LIST_HEAD(audit_freelist); |
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static struct sk_buff_head audit_skb_queue; |
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/* queue of skbs to send to auditd when/if it comes back */ static struct sk_buff_head audit_skb_hold_queue; |
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static struct task_struct *kauditd_task; static DECLARE_WAIT_QUEUE_HEAD(kauditd_wait); |
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static DECLARE_WAIT_QUEUE_HEAD(audit_backlog_wait); |
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static struct audit_features af = {.vers = AUDIT_FEATURE_VERSION, .mask = -1, .features = 0, .lock = 0,}; |
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static char *audit_feature_names[2] = { |
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"only_unset_loginuid", |
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"loginuid_immutable", |
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}; |
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/* Serialize requests from userspace. */ |
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DEFINE_MUTEX(audit_cmd_mutex); |
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/* AUDIT_BUFSIZ is the size of the temporary buffer used for formatting * audit records. Since printk uses a 1024 byte buffer, this buffer * should be at least that large. */ #define AUDIT_BUFSIZ 1024 /* AUDIT_MAXFREE is the number of empty audit_buffers we keep on the * audit_freelist. Doing so eliminates many kmalloc/kfree calls. */ #define AUDIT_MAXFREE (2*NR_CPUS) /* The audit_buffer is used when formatting an audit record. The caller * locks briefly to get the record off the freelist or to allocate the * buffer, and locks briefly to send the buffer to the netlink layer or * to place it on a transmit queue. Multiple audit_buffers can be in * use simultaneously. */ struct audit_buffer { struct list_head list; |
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struct sk_buff *skb; /* formatted skb ready to send */ |
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struct audit_context *ctx; /* NULL or associated context */ |
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gfp_t gfp_mask; |
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}; |
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struct audit_reply { |
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__u32 portid; |
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struct net *net; |
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struct sk_buff *skb; }; |
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static void audit_set_portid(struct audit_buffer *ab, __u32 portid) |
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{ |
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if (ab) { struct nlmsghdr *nlh = nlmsg_hdr(ab->skb); |
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nlh->nlmsg_pid = portid; |
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} |
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} |
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void audit_panic(const char *message) |
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{ |
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switch (audit_failure) { |
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case AUDIT_FAIL_SILENT: break; case AUDIT_FAIL_PRINTK: |
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if (printk_ratelimit()) |
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pr_err("%s ", message); |
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break; case AUDIT_FAIL_PANIC: |
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/* test audit_pid since printk is always losey, why bother? */ if (audit_pid) panic("audit: %s ", message); |
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break; } } static inline int audit_rate_check(void) { static unsigned long last_check = 0; static int messages = 0; static DEFINE_SPINLOCK(lock); unsigned long flags; unsigned long now; unsigned long elapsed; int retval = 0; if (!audit_rate_limit) return 1; spin_lock_irqsave(&lock, flags); if (++messages < audit_rate_limit) { retval = 1; } else { now = jiffies; elapsed = now - last_check; if (elapsed > HZ) { last_check = now; messages = 0; retval = 1; } } spin_unlock_irqrestore(&lock, flags); return retval; } |
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/** * audit_log_lost - conditionally log lost audit message event * @message: the message stating reason for lost audit message * * Emit at least 1 message per second, even if audit_rate_check is * throttling. * Always increment the lost messages counter. */ |
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void audit_log_lost(const char *message) { static unsigned long last_msg = 0; static DEFINE_SPINLOCK(lock); unsigned long flags; unsigned long now; int print; atomic_inc(&audit_lost); print = (audit_failure == AUDIT_FAIL_PANIC || !audit_rate_limit); if (!print) { spin_lock_irqsave(&lock, flags); now = jiffies; if (now - last_msg > HZ) { print = 1; last_msg = now; } spin_unlock_irqrestore(&lock, flags); } if (print) { |
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if (printk_ratelimit()) |
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pr_warn("audit_lost=%u audit_rate_limit=%u audit_backlog_limit=%u ", |
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atomic_read(&audit_lost), audit_rate_limit, audit_backlog_limit); |
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audit_panic(message); } |
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} |
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static int audit_log_config_change(char *function_name, u32 new, u32 old, |
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int allow_changes) |
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{ |
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struct audit_buffer *ab; int rc = 0; |
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ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); |
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if (unlikely(!ab)) return rc; |
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audit_log_format(ab, "%s=%u old=%u", function_name, new, old); |
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audit_log_session_info(ab); |
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rc = audit_log_task_context(ab); if (rc) allow_changes = 0; /* Something weird, deny request */ |
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audit_log_format(ab, " res=%d", allow_changes); audit_log_end(ab); |
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return rc; |
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} |
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static int audit_do_config_change(char *function_name, u32 *to_change, u32 new) |
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{ |
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int allow_changes, rc = 0; u32 old = *to_change; |
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/* check if we are locked */ |
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if (audit_enabled == AUDIT_LOCKED) allow_changes = 0; |
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else |
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allow_changes = 1; |
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if (audit_enabled != AUDIT_OFF) { |
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rc = audit_log_config_change(function_name, new, old, allow_changes); |
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if (rc) allow_changes = 0; |
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} |
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/* If we are allowed, make the change */ |
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if (allow_changes == 1) *to_change = new; |
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/* Not allowed, update reason */ else if (rc == 0) rc = -EPERM; return rc; |
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} |
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static int audit_set_rate_limit(u32 limit) |
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{ |
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return audit_do_config_change("audit_rate_limit", &audit_rate_limit, limit); |
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} |
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static int audit_set_backlog_limit(u32 limit) |
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{ |
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return audit_do_config_change("audit_backlog_limit", &audit_backlog_limit, limit); |
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} |
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static int audit_set_backlog_wait_time(u32 timeout) |
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{ return audit_do_config_change("audit_backlog_wait_time", |
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&audit_backlog_wait_time_master, timeout); |
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} |
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static int audit_set_enabled(u32 state) |
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{ |
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int rc; |
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if (state > AUDIT_LOCKED) |
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return -EINVAL; |
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rc = audit_do_config_change("audit_enabled", &audit_enabled, state); |
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if (!rc) audit_ever_enabled |= !!state; return rc; |
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} |
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static int audit_set_failure(u32 state) |
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{ |
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if (state != AUDIT_FAIL_SILENT && state != AUDIT_FAIL_PRINTK && state != AUDIT_FAIL_PANIC) return -EINVAL; |
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return audit_do_config_change("audit_failure", &audit_failure, state); |
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} |
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/* * Queue skbs to be sent to auditd when/if it comes back. These skbs should * already have been sent via prink/syslog and so if these messages are dropped * it is not a huge concern since we already passed the audit_log_lost() * notification and stuff. This is just nice to get audit messages during * boot before auditd is running or messages generated while auditd is stopped. * This only holds messages is audit_default is set, aka booting with audit=1 * or building your kernel that way. */ static void audit_hold_skb(struct sk_buff *skb) { if (audit_default && |
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(!audit_backlog_limit || skb_queue_len(&audit_skb_hold_queue) < audit_backlog_limit)) |
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skb_queue_tail(&audit_skb_hold_queue, skb); else kfree_skb(skb); } |
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/* * For one reason or another this nlh isn't getting delivered to the userspace * audit daemon, just send it to printk. */ static void audit_printk_skb(struct sk_buff *skb) { struct nlmsghdr *nlh = nlmsg_hdr(skb); |
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char *data = nlmsg_data(nlh); |
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if (nlh->nlmsg_type != AUDIT_EOE) { if (printk_ratelimit()) |
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pr_notice("type=%d %s ", nlh->nlmsg_type, data); |
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else |
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audit_log_lost("printk limit exceeded"); |
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} audit_hold_skb(skb); } |
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static void kauditd_send_skb(struct sk_buff *skb) { int err; |
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int attempts = 0; #define AUDITD_RETRIES 5 restart: |
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/* take a reference in case we can't send it and we want to hold it */ skb_get(skb); |
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err = netlink_unicast(audit_sock, skb, audit_nlk_portid, 0); |
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if (err < 0) { |
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pr_err("netlink_unicast sending to audit_pid=%d returned error: %d ", audit_pid, err); |
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if (audit_pid) { |
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if (err == -ECONNREFUSED || err == -EPERM || ++attempts >= AUDITD_RETRIES) { char s[32]; snprintf(s, sizeof(s), "audit_pid=%d reset", audit_pid); audit_log_lost(s); audit_pid = 0; audit_sock = NULL; } else { pr_warn("re-scheduling(#%d) write to audit_pid=%d ", attempts, audit_pid); set_current_state(TASK_INTERRUPTIBLE); schedule(); __set_current_state(TASK_RUNNING); goto restart; } |
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} |
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/* we might get lucky and get this in the next auditd */ audit_hold_skb(skb); } else /* drop the extra reference if sent ok */ |
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consume_skb(skb); |
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} |
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/* |
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* kauditd_send_multicast_skb - send the skb to multicast userspace listeners * * This function doesn't consume an skb as might be expected since it has to * copy it anyways. */ |
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static void kauditd_send_multicast_skb(struct sk_buff *skb, gfp_t gfp_mask) |
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{ struct sk_buff *copy; struct audit_net *aunet = net_generic(&init_net, audit_net_id); struct sock *sock = aunet->nlsk; |
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if (!netlink_has_listeners(sock, AUDIT_NLGRP_READLOG)) return; |
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/* * The seemingly wasteful skb_copy() rather than bumping the refcount * using skb_get() is necessary because non-standard mods are made to * the skb by the original kaudit unicast socket send routine. The * existing auditd daemon assumes this breakage. Fixing this would * require co-ordinating a change in the established protocol between * the kaudit kernel subsystem and the auditd userspace code. There is * no reason for new multicast clients to continue with this * non-compliance. */ |
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copy = skb_copy(skb, gfp_mask); |
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if (!copy) return; |
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nlmsg_multicast(sock, copy, 0, AUDIT_NLGRP_READLOG, gfp_mask); |
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} /* |
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* flush_hold_queue - empty the hold queue if auditd appears * * If auditd just started, drain the queue of messages already * sent to syslog/printk. Remember loss here is ok. We already * called audit_log_lost() if it didn't go out normally. so the * race between the skb_dequeue and the next check for audit_pid * doesn't matter. * * If you ever find kauditd to be too slow we can get a perf win * by doing our own locking and keeping better track if there * are messages in this queue. I don't see the need now, but * in 5 years when I want to play with this again I'll see this * note and still have no friggin idea what i'm thinking today. */ static void flush_hold_queue(void) |
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474 475 |
{ struct sk_buff *skb; |
b551d1d98
|
476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 |
if (!audit_default || !audit_pid) return; skb = skb_dequeue(&audit_skb_hold_queue); if (likely(!skb)) return; while (skb && audit_pid) { kauditd_send_skb(skb); skb = skb_dequeue(&audit_skb_hold_queue); } /* * if auditd just disappeared but we * dequeued an skb we need to drop ref */ if (skb) consume_skb(skb); } |
97a41e261
|
495 |
static int kauditd_thread(void *dummy) |
b7d112581
|
496 |
{ |
831441862
|
497 |
set_freezable(); |
4899b8b16
|
498 |
while (!kthread_should_stop()) { |
3320c5133
|
499 |
struct sk_buff *skb; |
3320c5133
|
500 |
|
b551d1d98
|
501 |
flush_hold_queue(); |
f3d357b09
|
502 |
|
b7d112581
|
503 |
skb = skb_dequeue(&audit_skb_queue); |
db8973194
|
504 |
|
b7d112581
|
505 |
if (skb) { |
db8973194
|
506 507 |
if (skb_queue_len(&audit_skb_queue) <= audit_backlog_limit) wake_up(&audit_backlog_wait); |
f3d357b09
|
508 509 |
if (audit_pid) kauditd_send_skb(skb); |
038cbcf65
|
510 511 |
else audit_printk_skb(skb); |
3320c5133
|
512 513 |
continue; } |
b7d112581
|
514 |
|
6b55fc63f
|
515 |
wait_event_freezable(kauditd_wait, skb_queue_len(&audit_skb_queue)); |
b7d112581
|
516 |
} |
4899b8b16
|
517 |
return 0; |
b7d112581
|
518 |
} |
9044e6bca
|
519 520 521 |
int audit_send_list(void *_dest) { struct audit_netlink_list *dest = _dest; |
9044e6bca
|
522 |
struct sk_buff *skb; |
48095d991
|
523 |
struct net *net = dest->net; |
33faba7fa
|
524 |
struct audit_net *aunet = net_generic(net, audit_net_id); |
9044e6bca
|
525 526 |
/* wait for parent to finish and send an ACK */ |
f368c07d7
|
527 528 |
mutex_lock(&audit_cmd_mutex); mutex_unlock(&audit_cmd_mutex); |
9044e6bca
|
529 530 |
while ((skb = __skb_dequeue(&dest->q)) != NULL) |
33faba7fa
|
531 |
netlink_unicast(aunet->nlsk, skb, dest->portid, 0); |
9044e6bca
|
532 |
|
48095d991
|
533 |
put_net(net); |
9044e6bca
|
534 535 536 537 |
kfree(dest); return 0; } |
f9441639e
|
538 |
struct sk_buff *audit_make_reply(__u32 portid, int seq, int type, int done, |
b8800aa5d
|
539 |
int multi, const void *payload, int size) |
9044e6bca
|
540 541 542 |
{ struct sk_buff *skb; struct nlmsghdr *nlh; |
9044e6bca
|
543 544 545 |
void *data; int flags = multi ? NLM_F_MULTI : 0; int t = done ? NLMSG_DONE : type; |
ee080e6ce
|
546 |
skb = nlmsg_new(size, GFP_KERNEL); |
9044e6bca
|
547 548 |
if (!skb) return NULL; |
f9441639e
|
549 |
nlh = nlmsg_put(skb, portid, seq, t, size, flags); |
c64e66c67
|
550 551 552 |
if (!nlh) goto out_kfree_skb; data = nlmsg_data(nlh); |
9044e6bca
|
553 554 |
memcpy(data, payload, size); return skb; |
c64e66c67
|
555 556 |
out_kfree_skb: kfree_skb(skb); |
9044e6bca
|
557 558 |
return NULL; } |
f09ac9db2
|
559 560 561 |
static int audit_send_reply_thread(void *arg) { struct audit_reply *reply = (struct audit_reply *)arg; |
48095d991
|
562 |
struct net *net = reply->net; |
33faba7fa
|
563 |
struct audit_net *aunet = net_generic(net, audit_net_id); |
f09ac9db2
|
564 565 566 567 568 569 |
mutex_lock(&audit_cmd_mutex); mutex_unlock(&audit_cmd_mutex); /* Ignore failure. It'll only happen if the sender goes away, because our timeout is set to infinite. */ |
33faba7fa
|
570 |
netlink_unicast(aunet->nlsk , reply->skb, reply->portid, 0); |
48095d991
|
571 |
put_net(net); |
f09ac9db2
|
572 573 574 |
kfree(reply); return 0; } |
b0dd25a82
|
575 576 |
/** * audit_send_reply - send an audit reply message via netlink |
d211f177b
|
577 |
* @request_skb: skb of request we are replying to (used to target the reply) |
b0dd25a82
|
578 579 580 581 582 583 584 |
* @seq: sequence number * @type: audit message type * @done: done (last) flag * @multi: multi-part message flag * @payload: payload data * @size: payload size * |
f9441639e
|
585 |
* Allocates an skb, builds the netlink message, and sends it to the port id. |
b0dd25a82
|
586 587 |
* No failure notifications. */ |
6f285b19d
|
588 |
static void audit_send_reply(struct sk_buff *request_skb, int seq, int type, int done, |
f9441639e
|
589 |
int multi, const void *payload, int size) |
1da177e4c
|
590 |
{ |
6f285b19d
|
591 592 |
u32 portid = NETLINK_CB(request_skb).portid; struct net *net = sock_net(NETLINK_CB(request_skb).sk); |
f09ac9db2
|
593 594 595 596 597 598 599 |
struct sk_buff *skb; struct task_struct *tsk; struct audit_reply *reply = kmalloc(sizeof(struct audit_reply), GFP_KERNEL); if (!reply) return; |
f9441639e
|
600 |
skb = audit_make_reply(portid, seq, type, done, multi, payload, size); |
1da177e4c
|
601 |
if (!skb) |
fcaf1eb86
|
602 |
goto out; |
f09ac9db2
|
603 |
|
6f285b19d
|
604 |
reply->net = get_net(net); |
f9441639e
|
605 |
reply->portid = portid; |
f09ac9db2
|
606 607 608 |
reply->skb = skb; tsk = kthread_run(audit_send_reply_thread, reply, "audit_send_reply"); |
fcaf1eb86
|
609 610 611 612 613 |
if (!IS_ERR(tsk)) return; kfree_skb(skb); out: kfree(reply); |
1da177e4c
|
614 615 616 617 618 619 |
} /* * Check for appropriate CAP_AUDIT_ capabilities on incoming audit * control messages. */ |
c7bdb545d
|
620 |
static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type) |
1da177e4c
|
621 622 |
{ int err = 0; |
5a3cb3b6c
|
623 |
/* Only support initial user namespace for now. */ |
aa4af831b
|
624 625 626 627 628 629 630 631 632 633 |
/* * We return ECONNREFUSED because it tricks userspace into thinking * that audit was not configured into the kernel. Lots of users * configure their PAM stack (because that's what the distro does) * to reject login if unable to send messages to audit. If we return * ECONNREFUSED the PAM stack thinks the kernel does not have audit * configured in and will let login proceed. If we return EPERM * userspace will reject all logins. This should be removed when we * support non init namespaces!! */ |
0b747172d
|
634 |
if (current_user_ns() != &init_user_ns) |
aa4af831b
|
635 |
return -ECONNREFUSED; |
34e36d8ec
|
636 |
|
1da177e4c
|
637 |
switch (msg_type) { |
1da177e4c
|
638 |
case AUDIT_LIST: |
1da177e4c
|
639 640 |
case AUDIT_ADD: case AUDIT_DEL: |
189009091
|
641 642 643 |
return -EOPNOTSUPP; case AUDIT_GET: case AUDIT_SET: |
b0fed4021
|
644 645 |
case AUDIT_GET_FEATURE: case AUDIT_SET_FEATURE: |
189009091
|
646 647 |
case AUDIT_LIST_RULES: case AUDIT_ADD_RULE: |
93315ed6d
|
648 |
case AUDIT_DEL_RULE: |
c2f0c7c35
|
649 |
case AUDIT_SIGNAL_INFO: |
522ed7767
|
650 651 |
case AUDIT_TTY_GET: case AUDIT_TTY_SET: |
74c3cbe33
|
652 653 |
case AUDIT_TRIM: case AUDIT_MAKE_EQUIV: |
5a3cb3b6c
|
654 655 |
/* Only support auditd and auditctl in initial pid namespace * for now. */ |
5985de675
|
656 |
if (task_active_pid_ns(current) != &init_pid_ns) |
5a3cb3b6c
|
657 |
return -EPERM; |
90f62cf30
|
658 |
if (!netlink_capable(skb, CAP_AUDIT_CONTROL)) |
1da177e4c
|
659 660 |
err = -EPERM; break; |
05474106a
|
661 |
case AUDIT_USER: |
039b6b3ed
|
662 663 |
case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG: case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2: |
90f62cf30
|
664 |
if (!netlink_capable(skb, CAP_AUDIT_WRITE)) |
1da177e4c
|
665 666 667 668 669 670 671 672 |
err = -EPERM; break; default: /* bad msg */ err = -EINVAL; } return err; } |
233a68667
|
673 |
static void audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type) |
50397bd1e
|
674 |
{ |
dc9eb698f
|
675 |
uid_t uid = from_kuid(&init_user_ns, current_uid()); |
f1dc4867f
|
676 |
pid_t pid = task_tgid_nr(current); |
50397bd1e
|
677 |
|
0868a5e15
|
678 |
if (!audit_enabled && msg_type != AUDIT_USER_AVC) { |
50397bd1e
|
679 |
*ab = NULL; |
233a68667
|
680 |
return; |
50397bd1e
|
681 682 683 |
} *ab = audit_log_start(NULL, GFP_KERNEL, msg_type); |
0644ec0cc
|
684 |
if (unlikely(!*ab)) |
233a68667
|
685 |
return; |
f1dc4867f
|
686 |
audit_log_format(*ab, "pid=%d uid=%u", pid, uid); |
4d3fb709b
|
687 |
audit_log_session_info(*ab); |
b122c3767
|
688 |
audit_log_task_context(*ab); |
50397bd1e
|
689 |
} |
b0fed4021
|
690 691 692 693 694 695 696 697 698 699 700 |
int is_audit_feature_set(int i) { return af.features & AUDIT_FEATURE_TO_MASK(i); } static int audit_get_feature(struct sk_buff *skb) { u32 seq; seq = nlmsg_hdr(skb)->nlmsg_seq; |
9ef915147
|
701 |
audit_send_reply(skb, seq, AUDIT_GET_FEATURE, 0, 0, &af, sizeof(af)); |
b0fed4021
|
702 703 704 705 706 707 708 709 |
return 0; } static void audit_log_feature_change(int which, u32 old_feature, u32 new_feature, u32 old_lock, u32 new_lock, int res) { struct audit_buffer *ab; |
b6c50fe0b
|
710 711 |
if (audit_enabled == AUDIT_OFF) return; |
b0fed4021
|
712 |
ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_FEATURE_CHANGE); |
ad2ac2632
|
713 |
audit_log_task_info(ab, current); |
897f1acbb
|
714 |
audit_log_format(ab, " feature=%s old=%u new=%u old_lock=%u new_lock=%u res=%d", |
b0fed4021
|
715 716 717 718 719 720 721 722 723 |
audit_feature_names[which], !!old_feature, !!new_feature, !!old_lock, !!new_lock, res); audit_log_end(ab); } static int audit_set_feature(struct sk_buff *skb) { struct audit_features *uaf; int i; |
6eed9b261
|
724 |
BUILD_BUG_ON(AUDIT_LAST_FEATURE + 1 > ARRAY_SIZE(audit_feature_names)); |
b0fed4021
|
725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 |
uaf = nlmsg_data(nlmsg_hdr(skb)); /* if there is ever a version 2 we should handle that here */ for (i = 0; i <= AUDIT_LAST_FEATURE; i++) { u32 feature = AUDIT_FEATURE_TO_MASK(i); u32 old_feature, new_feature, old_lock, new_lock; /* if we are not changing this feature, move along */ if (!(feature & uaf->mask)) continue; old_feature = af.features & feature; new_feature = uaf->features & feature; new_lock = (uaf->lock | af.lock) & feature; old_lock = af.lock & feature; /* are we changing a locked feature? */ |
4547b3bc4
|
743 |
if (old_lock && (new_feature != old_feature)) { |
b0fed4021
|
744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 |
audit_log_feature_change(i, old_feature, new_feature, old_lock, new_lock, 0); return -EPERM; } } /* nothing invalid, do the changes */ for (i = 0; i <= AUDIT_LAST_FEATURE; i++) { u32 feature = AUDIT_FEATURE_TO_MASK(i); u32 old_feature, new_feature, old_lock, new_lock; /* if we are not changing this feature, move along */ if (!(feature & uaf->mask)) continue; old_feature = af.features & feature; new_feature = uaf->features & feature; old_lock = af.lock & feature; new_lock = (uaf->lock | af.lock) & feature; if (new_feature != old_feature) audit_log_feature_change(i, old_feature, new_feature, old_lock, new_lock, 1); if (new_feature) af.features |= feature; else af.features &= ~feature; af.lock |= new_lock; } return 0; } |
1da177e4c
|
776 777 |
static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) { |
dc9eb698f
|
778 |
u32 seq; |
1da177e4c
|
779 |
void *data; |
1da177e4c
|
780 |
int err; |
c04049939
|
781 |
struct audit_buffer *ab; |
1da177e4c
|
782 |
u16 msg_type = nlh->nlmsg_type; |
e1396065e
|
783 |
struct audit_sig_info *sig_data; |
50397bd1e
|
784 |
char *ctx = NULL; |
e1396065e
|
785 |
u32 len; |
1da177e4c
|
786 |
|
c7bdb545d
|
787 |
err = audit_netlink_ok(skb, msg_type); |
1da177e4c
|
788 789 |
if (err) return err; |
b0dd25a82
|
790 791 |
/* As soon as there's any sign of userspace auditd, * start kauditd to talk to it */ |
13f51e1c3
|
792 |
if (!kauditd_task) { |
b7d112581
|
793 |
kauditd_task = kthread_run(kauditd_thread, NULL, "kauditd"); |
13f51e1c3
|
794 795 796 797 798 |
if (IS_ERR(kauditd_task)) { err = PTR_ERR(kauditd_task); kauditd_task = NULL; return err; } |
b7d112581
|
799 |
} |
1da177e4c
|
800 |
seq = nlh->nlmsg_seq; |
c64e66c67
|
801 |
data = nlmsg_data(nlh); |
1da177e4c
|
802 803 |
switch (msg_type) { |
09f883a90
|
804 805 806 807 808 809 810 811 812 813 |
case AUDIT_GET: { struct audit_status s; memset(&s, 0, sizeof(s)); s.enabled = audit_enabled; s.failure = audit_failure; s.pid = audit_pid; s.rate_limit = audit_rate_limit; s.backlog_limit = audit_backlog_limit; s.lost = atomic_read(&audit_lost); s.backlog = skb_queue_len(&audit_skb_queue); |
0288d7183
|
814 |
s.feature_bitmap = AUDIT_FEATURE_BITMAP_ALL; |
a77ed4e56
|
815 |
s.backlog_wait_time = audit_backlog_wait_time_master; |
6f285b19d
|
816 |
audit_send_reply(skb, seq, AUDIT_GET, 0, 0, &s, sizeof(s)); |
1da177e4c
|
817 |
break; |
09f883a90
|
818 819 820 821 822 823 824 825 |
} case AUDIT_SET: { struct audit_status s; memset(&s, 0, sizeof(s)); /* guard against past and future API changes */ memcpy(&s, data, min_t(size_t, sizeof(s), nlmsg_len(nlh))); if (s.mask & AUDIT_STATUS_ENABLED) { err = audit_set_enabled(s.enabled); |
20c6aaa39
|
826 827 |
if (err < 0) return err; |
1da177e4c
|
828 |
} |
09f883a90
|
829 830 |
if (s.mask & AUDIT_STATUS_FAILURE) { err = audit_set_failure(s.failure); |
20c6aaa39
|
831 832 |
if (err < 0) return err; |
1da177e4c
|
833 |
} |
09f883a90
|
834 835 |
if (s.mask & AUDIT_STATUS_PID) { int new_pid = s.pid; |
1a6b9f231
|
836 |
|
34eab0a7c
|
837 838 |
if ((!new_pid) && (task_tgid_vnr(current) != audit_pid)) return -EACCES; |
1a6b9f231
|
839 |
if (audit_enabled != AUDIT_OFF) |
dc9eb698f
|
840 |
audit_log_config_change("audit_pid", new_pid, audit_pid, 1); |
1a6b9f231
|
841 |
audit_pid = new_pid; |
15e473046
|
842 |
audit_nlk_portid = NETLINK_CB(skb).portid; |
de92fc97e
|
843 |
audit_sock = skb->sk; |
1da177e4c
|
844 |
} |
09f883a90
|
845 846 |
if (s.mask & AUDIT_STATUS_RATE_LIMIT) { err = audit_set_rate_limit(s.rate_limit); |
20c6aaa39
|
847 848 849 |
if (err < 0) return err; } |
51cc83f02
|
850 |
if (s.mask & AUDIT_STATUS_BACKLOG_LIMIT) { |
09f883a90
|
851 |
err = audit_set_backlog_limit(s.backlog_limit); |
51cc83f02
|
852 853 854 |
if (err < 0) return err; } |
3f0c5fad8
|
855 856 857 |
if (s.mask & AUDIT_STATUS_BACKLOG_WAIT_TIME) { if (sizeof(s) > (size_t)nlh->nlmsg_len) return -EINVAL; |
724e7bfcc
|
858 |
if (s.backlog_wait_time > 10*AUDIT_BACKLOG_WAIT_TIME) |
3f0c5fad8
|
859 860 861 862 |
return -EINVAL; err = audit_set_backlog_wait_time(s.backlog_wait_time); if (err < 0) return err; |
51cc83f02
|
863 |
} |
1da177e4c
|
864 |
break; |
09f883a90
|
865 |
} |
b0fed4021
|
866 867 868 869 870 871 872 873 874 875 |
case AUDIT_GET_FEATURE: err = audit_get_feature(skb); if (err) return err; break; case AUDIT_SET_FEATURE: err = audit_set_feature(skb); if (err) return err; break; |
05474106a
|
876 |
case AUDIT_USER: |
039b6b3ed
|
877 878 |
case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG: case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2: |
4a4cd633b
|
879 880 |
if (!audit_enabled && msg_type != AUDIT_USER_AVC) return 0; |
62062cf8a
|
881 |
err = audit_filter_user(msg_type); |
724e4fcc8
|
882 |
if (err == 1) { /* match or error */ |
4a4cd633b
|
883 |
err = 0; |
522ed7767
|
884 |
if (msg_type == AUDIT_USER_TTY) { |
152f497b9
|
885 |
err = tty_audit_push_current(); |
522ed7767
|
886 887 888 |
if (err) break; } |
1b7b533f6
|
889 |
mutex_unlock(&audit_cmd_mutex); |
dc9eb698f
|
890 |
audit_log_common_recv_msg(&ab, msg_type); |
50397bd1e
|
891 |
if (msg_type != AUDIT_USER_TTY) |
b50eba7e2
|
892 893 |
audit_log_format(ab, " msg='%.*s'", AUDIT_MESSAGE_TEXT_MAX, |
50397bd1e
|
894 895 896 |
(char *)data); else { int size; |
f7616102d
|
897 |
audit_log_format(ab, " data="); |
50397bd1e
|
898 |
size = nlmsg_len(nlh); |
55ad2f8d3
|
899 900 901 |
if (size > 0 && ((unsigned char *)data)[size - 1] == '\0') size--; |
b556f8ad5
|
902 |
audit_log_n_untrustedstring(ab, data, size); |
4a4cd633b
|
903 |
} |
f9441639e
|
904 |
audit_set_portid(ab, NETLINK_CB(skb).portid); |
50397bd1e
|
905 |
audit_log_end(ab); |
1b7b533f6
|
906 |
mutex_lock(&audit_cmd_mutex); |
0f45aa18e
|
907 |
} |
1da177e4c
|
908 |
break; |
93315ed6d
|
909 910 911 912 |
case AUDIT_ADD_RULE: case AUDIT_DEL_RULE: if (nlmsg_len(nlh) < sizeof(struct audit_rule_data)) return -EINVAL; |
1a6b9f231
|
913 |
if (audit_enabled == AUDIT_LOCKED) { |
dc9eb698f
|
914 915 |
audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE); audit_log_format(ab, " audit_enabled=%d res=0", audit_enabled); |
50397bd1e
|
916 |
audit_log_end(ab); |
6a01b07fa
|
917 918 |
return -EPERM; } |
ce0d9f046
|
919 |
err = audit_rule_change(msg_type, NETLINK_CB(skb).portid, |
dc9eb698f
|
920 |
seq, data, nlmsg_len(nlh)); |
1da177e4c
|
921 |
break; |
ce0d9f046
|
922 |
case AUDIT_LIST_RULES: |
6f285b19d
|
923 |
err = audit_list_rules_send(skb, seq); |
ce0d9f046
|
924 |
break; |
74c3cbe33
|
925 926 |
case AUDIT_TRIM: audit_trim_trees(); |
dc9eb698f
|
927 |
audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE); |
74c3cbe33
|
928 929 930 931 932 933 |
audit_log_format(ab, " op=trim res=1"); audit_log_end(ab); break; case AUDIT_MAKE_EQUIV: { void *bufp = data; u32 sizes[2]; |
7719e437f
|
934 |
size_t msglen = nlmsg_len(nlh); |
74c3cbe33
|
935 936 937 |
char *old, *new; err = -EINVAL; |
7719e437f
|
938 |
if (msglen < 2 * sizeof(u32)) |
74c3cbe33
|
939 940 941 |
break; memcpy(sizes, bufp, 2 * sizeof(u32)); bufp += 2 * sizeof(u32); |
7719e437f
|
942 943 |
msglen -= 2 * sizeof(u32); old = audit_unpack_string(&bufp, &msglen, sizes[0]); |
74c3cbe33
|
944 945 946 947 |
if (IS_ERR(old)) { err = PTR_ERR(old); break; } |
7719e437f
|
948 |
new = audit_unpack_string(&bufp, &msglen, sizes[1]); |
74c3cbe33
|
949 950 951 952 953 954 955 |
if (IS_ERR(new)) { err = PTR_ERR(new); kfree(old); break; } /* OK, here comes... */ err = audit_tag_tree(old, new); |
dc9eb698f
|
956 |
audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE); |
50397bd1e
|
957 |
|
74c3cbe33
|
958 959 960 961 962 963 964 965 966 967 |
audit_log_format(ab, " op=make_equiv old="); audit_log_untrustedstring(ab, old); audit_log_format(ab, " new="); audit_log_untrustedstring(ab, new); audit_log_format(ab, " res=%d", !err); audit_log_end(ab); kfree(old); kfree(new); break; } |
c2f0c7c35
|
968 |
case AUDIT_SIGNAL_INFO: |
939cbf260
|
969 970 971 972 973 974 |
len = 0; if (audit_sig_sid) { err = security_secid_to_secctx(audit_sig_sid, &ctx, &len); if (err) return err; } |
e1396065e
|
975 976 |
sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL); if (!sig_data) { |
939cbf260
|
977 978 |
if (audit_sig_sid) security_release_secctx(ctx, len); |
e1396065e
|
979 980 |
return -ENOMEM; } |
cca080d9b
|
981 |
sig_data->uid = from_kuid(&init_user_ns, audit_sig_uid); |
e1396065e
|
982 |
sig_data->pid = audit_sig_pid; |
939cbf260
|
983 984 985 986 |
if (audit_sig_sid) { memcpy(sig_data->ctx, ctx, len); security_release_secctx(ctx, len); } |
6f285b19d
|
987 988 |
audit_send_reply(skb, seq, AUDIT_SIGNAL_INFO, 0, 0, sig_data, sizeof(*sig_data) + len); |
e1396065e
|
989 |
kfree(sig_data); |
c2f0c7c35
|
990 |
break; |
522ed7767
|
991 992 |
case AUDIT_TTY_GET: { struct audit_tty_status s; |
8aa14b649
|
993 |
struct task_struct *tsk = current; |
7173c54e3
|
994 |
spin_lock(&tsk->sighand->siglock); |
b95d77fe3
|
995 |
s.enabled = tsk->signal->audit_tty; |
46e959ea2
|
996 |
s.log_passwd = tsk->signal->audit_tty_log_passwd; |
7173c54e3
|
997 |
spin_unlock(&tsk->sighand->siglock); |
8aa14b649
|
998 |
|
6f285b19d
|
999 |
audit_send_reply(skb, seq, AUDIT_TTY_GET, 0, 0, &s, sizeof(s)); |
522ed7767
|
1000 1001 1002 |
break; } case AUDIT_TTY_SET: { |
a06e56b2a
|
1003 |
struct audit_tty_status s, old; |
8aa14b649
|
1004 |
struct task_struct *tsk = current; |
a06e56b2a
|
1005 |
struct audit_buffer *ab; |
0e23bacca
|
1006 1007 1008 1009 1010 1011 1012 1013 |
memset(&s, 0, sizeof(s)); /* guard against past and future API changes */ memcpy(&s, data, min_t(size_t, sizeof(s), nlmsg_len(nlh))); /* check if new data is valid */ if ((s.enabled != 0 && s.enabled != 1) || (s.log_passwd != 0 && s.log_passwd != 1)) err = -EINVAL; |
a06e56b2a
|
1014 1015 1016 1017 |
spin_lock(&tsk->sighand->siglock); old.enabled = tsk->signal->audit_tty; old.log_passwd = tsk->signal->audit_tty_log_passwd; |
0e23bacca
|
1018 1019 1020 1021 |
if (!err) { tsk->signal->audit_tty = s.enabled; tsk->signal->audit_tty_log_passwd = s.log_passwd; } |
a06e56b2a
|
1022 |
spin_unlock(&tsk->sighand->siglock); |
522ed7767
|
1023 |
|
a06e56b2a
|
1024 |
audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE); |
1ce319f11
|
1025 1026 1027 1028 |
audit_log_format(ab, " op=tty_set old-enabled=%d new-enabled=%d" " old-log_passwd=%d new-log_passwd=%d res=%d", old.enabled, s.enabled, old.log_passwd, s.log_passwd, !err); |
a06e56b2a
|
1029 |
audit_log_end(ab); |
522ed7767
|
1030 1031 |
break; } |
1da177e4c
|
1032 1033 1034 1035 1036 1037 1038 |
default: err = -EINVAL; break; } return err < 0 ? err : 0; } |
b0dd25a82
|
1039 |
/* |
ea7ae60bf
|
1040 1041 |
* Get message from skb. Each message is processed by audit_receive_msg. * Malformed skbs with wrong length are discarded silently. |
b0dd25a82
|
1042 |
*/ |
2a0a6ebee
|
1043 |
static void audit_receive_skb(struct sk_buff *skb) |
1da177e4c
|
1044 |
{ |
ea7ae60bf
|
1045 1046 |
struct nlmsghdr *nlh; /* |
941912133
|
1047 |
* len MUST be signed for nlmsg_next to be able to dec it below 0 |
ea7ae60bf
|
1048 1049 1050 1051 1052 1053 1054 |
* if the nlmsg_len was not aligned */ int len; int err; nlh = nlmsg_hdr(skb); len = skb->len; |
941912133
|
1055 |
while (nlmsg_ok(nlh, len)) { |
ea7ae60bf
|
1056 1057 1058 |
err = audit_receive_msg(skb, nlh); /* if err or if this message says it wants a response */ if (err || (nlh->nlmsg_flags & NLM_F_ACK)) |
1da177e4c
|
1059 |
netlink_ack(skb, nlh, err); |
ea7ae60bf
|
1060 |
|
2851da570
|
1061 |
nlh = nlmsg_next(nlh, &len); |
1da177e4c
|
1062 |
} |
1da177e4c
|
1063 1064 1065 |
} /* Receive messages from netlink socket. */ |
cd40b7d39
|
1066 |
static void audit_receive(struct sk_buff *skb) |
1da177e4c
|
1067 |
{ |
f368c07d7
|
1068 |
mutex_lock(&audit_cmd_mutex); |
cd40b7d39
|
1069 |
audit_receive_skb(skb); |
f368c07d7
|
1070 |
mutex_unlock(&audit_cmd_mutex); |
1da177e4c
|
1071 |
} |
3a101b8de
|
1072 |
/* Run custom bind function on netlink socket group connect or bind requests. */ |
023e2cfa3
|
1073 |
static int audit_bind(struct net *net, int group) |
3a101b8de
|
1074 1075 1076 1077 1078 1079 |
{ if (!capable(CAP_AUDIT_READ)) return -EPERM; return 0; } |
33faba7fa
|
1080 |
static int __net_init audit_net_init(struct net *net) |
1da177e4c
|
1081 |
{ |
a31f2d17b
|
1082 1083 |
struct netlink_kernel_cfg cfg = { .input = audit_receive, |
3a101b8de
|
1084 |
.bind = audit_bind, |
451f92163
|
1085 1086 |
.flags = NL_CFG_F_NONROOT_RECV, .groups = AUDIT_NLGRP_MAX, |
a31f2d17b
|
1087 |
}; |
f368c07d7
|
1088 |
|
33faba7fa
|
1089 |
struct audit_net *aunet = net_generic(net, audit_net_id); |
33faba7fa
|
1090 |
aunet->nlsk = netlink_kernel_create(net, NETLINK_AUDIT, &cfg); |
11ee39ebf
|
1091 |
if (aunet->nlsk == NULL) { |
33faba7fa
|
1092 |
audit_panic("cannot initialize netlink socket in namespace"); |
11ee39ebf
|
1093 1094 1095 |
return -ENOMEM; } aunet->nlsk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; |
33faba7fa
|
1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 |
return 0; } static void __net_exit audit_net_exit(struct net *net) { struct audit_net *aunet = net_generic(net, audit_net_id); struct sock *sock = aunet->nlsk; if (sock == audit_sock) { audit_pid = 0; audit_sock = NULL; } |
e231d54c1
|
1107 |
RCU_INIT_POINTER(aunet->nlsk, NULL); |
33faba7fa
|
1108 1109 1110 |
synchronize_net(); netlink_kernel_release(sock); } |
8626877b5
|
1111 |
static struct pernet_operations audit_net_ops __net_initdata = { |
33faba7fa
|
1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 |
.init = audit_net_init, .exit = audit_net_exit, .id = &audit_net_id, .size = sizeof(struct audit_net), }; /* Initialize audit support at boot time. */ static int __init audit_init(void) { int i; |
a3f07114e
|
1122 1123 |
if (audit_initialized == AUDIT_DISABLED) return 0; |
d957f7b72
|
1124 1125 1126 |
pr_info("initializing netlink subsys (%s) ", audit_default ? "enabled" : "disabled"); |
33faba7fa
|
1127 |
register_pernet_subsys(&audit_net_ops); |
1da177e4c
|
1128 |
|
b7d112581
|
1129 |
skb_queue_head_init(&audit_skb_queue); |
f3d357b09
|
1130 |
skb_queue_head_init(&audit_skb_hold_queue); |
a3f07114e
|
1131 |
audit_initialized = AUDIT_INITIALIZED; |
1da177e4c
|
1132 |
audit_enabled = audit_default; |
b593d384e
|
1133 |
audit_ever_enabled |= !!audit_default; |
3dc7e3153
|
1134 |
|
9ad9ad385
|
1135 |
audit_log(NULL, GFP_KERNEL, AUDIT_KERNEL, "initialized"); |
f368c07d7
|
1136 |
|
f368c07d7
|
1137 1138 |
for (i = 0; i < AUDIT_INODE_BUCKETS; i++) INIT_LIST_HEAD(&audit_inode_hash[i]); |
f368c07d7
|
1139 |
|
1da177e4c
|
1140 1141 |
return 0; } |
1da177e4c
|
1142 1143 1144 1145 1146 1147 |
__initcall(audit_init); /* Process kernel command-line parameter at boot time. audit=0 or audit=1. */ static int __init audit_enable(char *str) { audit_default = !!simple_strtol(str, NULL, 0); |
a3f07114e
|
1148 1149 |
if (!audit_default) audit_initialized = AUDIT_DISABLED; |
d957f7b72
|
1150 1151 |
pr_info("%s ", audit_default ? |
d3ca0344b
|
1152 |
"enabled (after initialization)" : "disabled (until reboot)"); |
a3f07114e
|
1153 |
|
9b41046cd
|
1154 |
return 1; |
1da177e4c
|
1155 |
} |
1da177e4c
|
1156 |
__setup("audit=", audit_enable); |
f910fde73
|
1157 1158 1159 1160 |
/* Process kernel command-line parameter at boot time. * audit_backlog_limit=<n> */ static int __init audit_backlog_limit_set(char *str) { |
3e1d0bb62
|
1161 |
u32 audit_backlog_limit_arg; |
d957f7b72
|
1162 |
|
f910fde73
|
1163 |
pr_info("audit_backlog_limit: "); |
3e1d0bb62
|
1164 1165 1166 |
if (kstrtouint(str, 0, &audit_backlog_limit_arg)) { pr_cont("using default of %u, unable to parse %s ", |
d957f7b72
|
1167 |
audit_backlog_limit, str); |
f910fde73
|
1168 1169 |
return 1; } |
3e1d0bb62
|
1170 1171 |
audit_backlog_limit = audit_backlog_limit_arg; |
d957f7b72
|
1172 1173 |
pr_cont("%d ", audit_backlog_limit); |
f910fde73
|
1174 1175 1176 1177 |
return 1; } __setup("audit_backlog_limit=", audit_backlog_limit_set); |
16e1904e6
|
1178 1179 1180 |
static void audit_buffer_free(struct audit_buffer *ab) { unsigned long flags; |
8fc6115c2
|
1181 1182 |
if (!ab) return; |
5ac52f33b
|
1183 1184 |
if (ab->skb) kfree_skb(ab->skb); |
b7d112581
|
1185 |
|
16e1904e6
|
1186 |
spin_lock_irqsave(&audit_freelist_lock, flags); |
5d136a010
|
1187 |
if (audit_freelist_count > AUDIT_MAXFREE) |
16e1904e6
|
1188 |
kfree(ab); |
5d136a010
|
1189 1190 |
else { audit_freelist_count++; |
16e1904e6
|
1191 |
list_add(&ab->list, &audit_freelist); |
5d136a010
|
1192 |
} |
16e1904e6
|
1193 1194 |
spin_unlock_irqrestore(&audit_freelist_lock, flags); } |
c04049939
|
1195 |
static struct audit_buffer * audit_buffer_alloc(struct audit_context *ctx, |
dd0fc66fb
|
1196 |
gfp_t gfp_mask, int type) |
16e1904e6
|
1197 1198 1199 |
{ unsigned long flags; struct audit_buffer *ab = NULL; |
c04049939
|
1200 |
struct nlmsghdr *nlh; |
16e1904e6
|
1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 |
spin_lock_irqsave(&audit_freelist_lock, flags); if (!list_empty(&audit_freelist)) { ab = list_entry(audit_freelist.next, struct audit_buffer, list); list_del(&ab->list); --audit_freelist_count; } spin_unlock_irqrestore(&audit_freelist_lock, flags); if (!ab) { |
4332bdd33
|
1212 |
ab = kmalloc(sizeof(*ab), gfp_mask); |
16e1904e6
|
1213 |
if (!ab) |
8fc6115c2
|
1214 |
goto err; |
16e1904e6
|
1215 |
} |
8fc6115c2
|
1216 |
|
b7d112581
|
1217 |
ab->ctx = ctx; |
9ad9ad385
|
1218 |
ab->gfp_mask = gfp_mask; |
ee080e6ce
|
1219 1220 1221 |
ab->skb = nlmsg_new(AUDIT_BUFSIZ, gfp_mask); if (!ab->skb) |
c64e66c67
|
1222 |
goto err; |
ee080e6ce
|
1223 |
|
c64e66c67
|
1224 1225 1226 |
nlh = nlmsg_put(ab->skb, 0, 0, type, 0, 0); if (!nlh) goto out_kfree_skb; |
ee080e6ce
|
1227 |
|
16e1904e6
|
1228 |
return ab; |
ee080e6ce
|
1229 |
|
c64e66c67
|
1230 |
out_kfree_skb: |
ee080e6ce
|
1231 1232 |
kfree_skb(ab->skb); ab->skb = NULL; |
8fc6115c2
|
1233 1234 1235 |
err: audit_buffer_free(ab); return NULL; |
16e1904e6
|
1236 |
} |
1da177e4c
|
1237 |
|
b0dd25a82
|
1238 1239 1240 1241 |
/** * audit_serial - compute a serial number for the audit record * * Compute a serial number for the audit record. Audit records are |
bfb4496e7
|
1242 1243 1244 1245 1246 1247 1248 |
* written to user-space as soon as they are generated, so a complete * audit record may be written in several pieces. The timestamp of the * record and this serial number are used by the user-space tools to * determine which pieces belong to the same audit record. The * (timestamp,serial) tuple is unique for each syscall and is live from * syscall entry to syscall exit. * |
bfb4496e7
|
1249 1250 1251 1252 |
* NOTE: Another possibility is to store the formatted records off the * audit context (for those records that have a context), and emit them * all at syscall exit. However, this could delay the reporting of * significant errors until syscall exit (or never, if the system |
b0dd25a82
|
1253 1254 |
* halts). */ |
bfb4496e7
|
1255 1256 |
unsigned int audit_serial(void) { |
01478d7d6
|
1257 |
static atomic_t serial = ATOMIC_INIT(0); |
d5b454f2c
|
1258 |
|
01478d7d6
|
1259 |
return atomic_add_return(1, &serial); |
bfb4496e7
|
1260 |
} |
5600b8927
|
1261 |
static inline void audit_get_stamp(struct audit_context *ctx, |
bfb4496e7
|
1262 1263 |
struct timespec *t, unsigned int *serial) { |
48887e63d
|
1264 |
if (!ctx || !auditsc_get_stamp(ctx, t, serial)) { |
bfb4496e7
|
1265 1266 1267 1268 |
*t = CURRENT_TIME; *serial = audit_serial(); } } |
829199197
|
1269 1270 1271 |
/* * Wait for auditd to drain the queue a little */ |
c81825dd6
|
1272 |
static long wait_for_auditd(long sleep_time) |
829199197
|
1273 1274 |
{ DECLARE_WAITQUEUE(wait, current); |
f000cfdde
|
1275 |
set_current_state(TASK_UNINTERRUPTIBLE); |
7ecf69bf5
|
1276 |
add_wait_queue_exclusive(&audit_backlog_wait, &wait); |
829199197
|
1277 1278 1279 |
if (audit_backlog_limit && skb_queue_len(&audit_skb_queue) > audit_backlog_limit) |
c81825dd6
|
1280 |
sleep_time = schedule_timeout(sleep_time); |
829199197
|
1281 1282 1283 |
__set_current_state(TASK_RUNNING); remove_wait_queue(&audit_backlog_wait, &wait); |
ae887e0bd
|
1284 |
|
c81825dd6
|
1285 |
return sleep_time; |
829199197
|
1286 |
} |
b0dd25a82
|
1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 |
/** * audit_log_start - obtain an audit buffer * @ctx: audit_context (may be NULL) * @gfp_mask: type of allocation * @type: audit message type * * Returns audit_buffer pointer on success or NULL on error. * * Obtain an audit buffer. This routine does locking to obtain the * audit buffer, but then no locking is required for calls to * audit_log_*format. If the task (ctx) is a task that is currently in a * syscall, then the syscall is marked as auditable and an audit record * will be written at syscall exit. If there is no associated task, then * task context (ctx) should be NULL. */ |
9796fdd82
|
1302 |
struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, |
9ad9ad385
|
1303 |
int type) |
1da177e4c
|
1304 1305 |
{ struct audit_buffer *ab = NULL; |
1da177e4c
|
1306 |
struct timespec t; |
ef00be055
|
1307 |
unsigned int uninitialized_var(serial); |
6dd80aba9
|
1308 1309 |
int reserve = 5; /* Allow atomic callers to go up to five entries over the normal backlog limit */ |
ac4cec443
|
1310 |
unsigned long timeout_start = jiffies; |
1da177e4c
|
1311 |
|
a3f07114e
|
1312 |
if (audit_initialized != AUDIT_INITIALIZED) |
1da177e4c
|
1313 |
return NULL; |
c8edc80c8
|
1314 1315 |
if (unlikely(audit_filter_type(type))) return NULL; |
d0164adc8
|
1316 |
if (gfp_mask & __GFP_DIRECT_RECLAIM) { |
6dd80aba9
|
1317 |
if (audit_pid && audit_pid == current->pid) |
d0164adc8
|
1318 |
gfp_mask &= ~__GFP_DIRECT_RECLAIM; |
6dd80aba9
|
1319 1320 1321 |
else reserve = 0; } |
9ad9ad385
|
1322 1323 1324 |
while (audit_backlog_limit && skb_queue_len(&audit_skb_queue) > audit_backlog_limit + reserve) { |
d0164adc8
|
1325 |
if (gfp_mask & __GFP_DIRECT_RECLAIM && audit_backlog_wait_time) { |
c81825dd6
|
1326 |
long sleep_time; |
9ad9ad385
|
1327 |
|
c81825dd6
|
1328 1329 |
sleep_time = timeout_start + audit_backlog_wait_time - jiffies; if (sleep_time > 0) { |
ae887e0bd
|
1330 |
sleep_time = wait_for_auditd(sleep_time); |
c81825dd6
|
1331 |
if (sleep_time > 0) |
ae887e0bd
|
1332 |
continue; |
8ac1c8d5d
|
1333 |
} |
9ad9ad385
|
1334 |
} |
320f1b1ed
|
1335 |
if (audit_rate_check() && printk_ratelimit()) |
d957f7b72
|
1336 1337 1338 1339 |
pr_warn("audit_backlog=%d > audit_backlog_limit=%d ", skb_queue_len(&audit_skb_queue), audit_backlog_limit); |
fb19b4c6a
|
1340 |
audit_log_lost("backlog limit exceeded"); |
ac4cec443
|
1341 1342 |
audit_backlog_wait_time = audit_backlog_wait_overflow; wake_up(&audit_backlog_wait); |
fb19b4c6a
|
1343 1344 |
return NULL; } |
efef73a1a
|
1345 1346 |
if (!reserve) audit_backlog_wait_time = audit_backlog_wait_time_master; |
e789e561a
|
1347 |
|
9ad9ad385
|
1348 |
ab = audit_buffer_alloc(ctx, gfp_mask, type); |
1da177e4c
|
1349 1350 1351 1352 |
if (!ab) { audit_log_lost("out of memory in audit_log_start"); return NULL; } |
bfb4496e7
|
1353 |
audit_get_stamp(ab->ctx, &t, &serial); |
197c69c6a
|
1354 |
|
1da177e4c
|
1355 1356 1357 1358 |
audit_log_format(ab, "audit(%lu.%03lu:%u): ", t.tv_sec, t.tv_nsec/1000000, serial); return ab; } |
8fc6115c2
|
1359 |
/** |
5ac52f33b
|
1360 |
* audit_expand - expand skb in the audit buffer |
8fc6115c2
|
1361 |
* @ab: audit_buffer |
b0dd25a82
|
1362 |
* @extra: space to add at tail of the skb |
8fc6115c2
|
1363 1364 1365 1366 |
* * Returns 0 (no space) on failed expansion, or available space if * successful. */ |
e3b926b4c
|
1367 |
static inline int audit_expand(struct audit_buffer *ab, int extra) |
8fc6115c2
|
1368 |
{ |
5ac52f33b
|
1369 |
struct sk_buff *skb = ab->skb; |
406a1d868
|
1370 1371 1372 |
int oldtail = skb_tailroom(skb); int ret = pskb_expand_head(skb, 0, extra, ab->gfp_mask); int newtail = skb_tailroom(skb); |
5ac52f33b
|
1373 1374 |
if (ret < 0) { audit_log_lost("out of memory in audit_expand"); |
8fc6115c2
|
1375 |
return 0; |
5ac52f33b
|
1376 |
} |
406a1d868
|
1377 1378 1379 |
skb->truesize += newtail - oldtail; return newtail; |
8fc6115c2
|
1380 |
} |
1da177e4c
|
1381 |
|
b0dd25a82
|
1382 1383 |
/* * Format an audit message into the audit buffer. If there isn't enough |
1da177e4c
|
1384 1385 |
* room in the audit buffer, more room will be allocated and vsnprint * will be called a second time. Currently, we assume that a printk |
b0dd25a82
|
1386 1387 |
* can't format message larger than 1024 bytes, so we don't either. */ |
1da177e4c
|
1388 1389 1390 1391 |
static void audit_log_vformat(struct audit_buffer *ab, const char *fmt, va_list args) { int len, avail; |
5ac52f33b
|
1392 |
struct sk_buff *skb; |
eecb0a733
|
1393 |
va_list args2; |
1da177e4c
|
1394 1395 1396 |
if (!ab) return; |
5ac52f33b
|
1397 1398 1399 1400 |
BUG_ON(!ab->skb); skb = ab->skb; avail = skb_tailroom(skb); if (avail == 0) { |
e3b926b4c
|
1401 |
avail = audit_expand(ab, AUDIT_BUFSIZ); |
8fc6115c2
|
1402 1403 |
if (!avail) goto out; |
1da177e4c
|
1404 |
} |
eecb0a733
|
1405 |
va_copy(args2, args); |
27a884dc3
|
1406 |
len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args); |
1da177e4c
|
1407 1408 1409 1410 |
if (len >= avail) { /* The printk buffer is 1024 bytes long, so if we get * here and AUDIT_BUFSIZ is at least 1024, then we can * log everything that printk could have logged. */ |
b0dd25a82
|
1411 1412 |
avail = audit_expand(ab, max_t(unsigned, AUDIT_BUFSIZ, 1+len-avail)); |
8fc6115c2
|
1413 |
if (!avail) |
a0e86bd42
|
1414 |
goto out_va_end; |
27a884dc3
|
1415 |
len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args2); |
1da177e4c
|
1416 |
} |
168b71739
|
1417 1418 |
if (len > 0) skb_put(skb, len); |
a0e86bd42
|
1419 1420 |
out_va_end: va_end(args2); |
8fc6115c2
|
1421 1422 |
out: return; |
1da177e4c
|
1423 |
} |
b0dd25a82
|
1424 1425 1426 1427 1428 1429 1430 1431 |
/** * audit_log_format - format a message into the audit buffer. * @ab: audit_buffer * @fmt: format string * @...: optional parameters matching @fmt string * * All the work is done in audit_log_vformat. */ |
1da177e4c
|
1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 |
void audit_log_format(struct audit_buffer *ab, const char *fmt, ...) { va_list args; if (!ab) return; va_start(args, fmt); audit_log_vformat(ab, fmt, args); va_end(args); } |
b0dd25a82
|
1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 |
/** * audit_log_hex - convert a buffer to hex and append it to the audit skb * @ab: the audit_buffer * @buf: buffer to convert to hex * @len: length of @buf to be converted * * No return value; failure to expand is silently ignored. * * This function will take the passed buf and convert it into a string of * ascii hex digits. The new string is placed onto the skb. */ |
b556f8ad5
|
1453 |
void audit_log_n_hex(struct audit_buffer *ab, const unsigned char *buf, |
168b71739
|
1454 |
size_t len) |
83c7d0917
|
1455 |
{ |
168b71739
|
1456 1457 1458 |
int i, avail, new_len; unsigned char *ptr; struct sk_buff *skb; |
168b71739
|
1459 |
|
8ef2d3040
|
1460 1461 |
if (!ab) return; |
168b71739
|
1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 |
BUG_ON(!ab->skb); skb = ab->skb; avail = skb_tailroom(skb); new_len = len<<1; if (new_len >= avail) { /* Round the buffer request up to the next multiple */ new_len = AUDIT_BUFSIZ*(((new_len-avail)/AUDIT_BUFSIZ) + 1); avail = audit_expand(ab, new_len); if (!avail) return; } |
83c7d0917
|
1473 |
|
27a884dc3
|
1474 |
ptr = skb_tail_pointer(skb); |
b8dbc3241
|
1475 1476 |
for (i = 0; i < len; i++) ptr = hex_byte_pack_upper(ptr, buf[i]); |
168b71739
|
1477 1478 |
*ptr = 0; skb_put(skb, len << 1); /* new string is twice the old string */ |
83c7d0917
|
1479 |
} |
9c937dcc7
|
1480 1481 1482 1483 |
/* * Format a string of no more than slen characters into the audit buffer, * enclosed in quote marks. */ |
b556f8ad5
|
1484 1485 |
void audit_log_n_string(struct audit_buffer *ab, const char *string, size_t slen) |
9c937dcc7
|
1486 1487 1488 1489 |
{ int avail, new_len; unsigned char *ptr; struct sk_buff *skb; |
8ef2d3040
|
1490 1491 |
if (!ab) return; |
9c937dcc7
|
1492 1493 1494 1495 1496 1497 1498 1499 1500 |
BUG_ON(!ab->skb); skb = ab->skb; avail = skb_tailroom(skb); new_len = slen + 3; /* enclosing quotes + null terminator */ if (new_len > avail) { avail = audit_expand(ab, new_len); if (!avail) return; } |
27a884dc3
|
1501 |
ptr = skb_tail_pointer(skb); |
9c937dcc7
|
1502 1503 1504 1505 1506 1507 1508 |
*ptr++ = '"'; memcpy(ptr, string, slen); ptr += slen; *ptr++ = '"'; *ptr = 0; skb_put(skb, slen + 2); /* don't include null terminator */ } |
b0dd25a82
|
1509 |
/** |
de6bbd1d3
|
1510 |
* audit_string_contains_control - does a string need to be logged in hex |
f706d5d22
|
1511 1512 |
* @string: string to be checked * @len: max length of the string to check |
de6bbd1d3
|
1513 |
*/ |
9fcf836b2
|
1514 |
bool audit_string_contains_control(const char *string, size_t len) |
de6bbd1d3
|
1515 1516 |
{ const unsigned char *p; |
b3897f567
|
1517 |
for (p = string; p < (const unsigned char *)string + len; p++) { |
1d6c9649e
|
1518 |
if (*p == '"' || *p < 0x21 || *p > 0x7e) |
9fcf836b2
|
1519 |
return true; |
de6bbd1d3
|
1520 |
} |
9fcf836b2
|
1521 |
return false; |
de6bbd1d3
|
1522 1523 1524 |
} /** |
522ed7767
|
1525 |
* audit_log_n_untrustedstring - log a string that may contain random characters |
b0dd25a82
|
1526 |
* @ab: audit_buffer |
f706d5d22
|
1527 |
* @len: length of string (not including trailing null) |
b0dd25a82
|
1528 1529 1530 1531 |
* @string: string to be logged * * This code will escape a string that is passed to it if the string * contains a control character, unprintable character, double quote mark, |
168b71739
|
1532 |
* or a space. Unescaped strings will start and end with a double quote mark. |
b0dd25a82
|
1533 |
* Strings that are escaped are printed in hex (2 digits per char). |
9c937dcc7
|
1534 1535 1536 |
* * The caller specifies the number of characters in the string to log, which may * or may not be the entire string. |
b0dd25a82
|
1537 |
*/ |
b556f8ad5
|
1538 1539 |
void audit_log_n_untrustedstring(struct audit_buffer *ab, const char *string, size_t len) |
83c7d0917
|
1540 |
{ |
de6bbd1d3
|
1541 |
if (audit_string_contains_control(string, len)) |
b556f8ad5
|
1542 |
audit_log_n_hex(ab, string, len); |
de6bbd1d3
|
1543 |
else |
b556f8ad5
|
1544 |
audit_log_n_string(ab, string, len); |
83c7d0917
|
1545 |
} |
9c937dcc7
|
1546 |
/** |
522ed7767
|
1547 |
* audit_log_untrustedstring - log a string that may contain random characters |
9c937dcc7
|
1548 1549 1550 |
* @ab: audit_buffer * @string: string to be logged * |
522ed7767
|
1551 |
* Same as audit_log_n_untrustedstring(), except that strlen is used to |
9c937dcc7
|
1552 1553 |
* determine string length. */ |
de6bbd1d3
|
1554 |
void audit_log_untrustedstring(struct audit_buffer *ab, const char *string) |
9c937dcc7
|
1555 |
{ |
b556f8ad5
|
1556 |
audit_log_n_untrustedstring(ab, string, strlen(string)); |
9c937dcc7
|
1557 |
} |
168b71739
|
1558 |
/* This is a helper-function to print the escaped d_path */ |
1da177e4c
|
1559 |
void audit_log_d_path(struct audit_buffer *ab, const char *prefix, |
66b3fad3f
|
1560 |
const struct path *path) |
1da177e4c
|
1561 |
{ |
44707fdf5
|
1562 |
char *p, *pathname; |
1da177e4c
|
1563 |
|
8fc6115c2
|
1564 |
if (prefix) |
c158a35c8
|
1565 |
audit_log_format(ab, "%s", prefix); |
1da177e4c
|
1566 |
|
168b71739
|
1567 |
/* We will allow 11 spaces for ' (deleted)' to be appended */ |
44707fdf5
|
1568 1569 |
pathname = kmalloc(PATH_MAX+11, ab->gfp_mask); if (!pathname) { |
def575434
|
1570 |
audit_log_string(ab, "<no_memory>"); |
168b71739
|
1571 |
return; |
1da177e4c
|
1572 |
} |
cf28b4863
|
1573 |
p = d_path(path, pathname, PATH_MAX+11); |
168b71739
|
1574 1575 |
if (IS_ERR(p)) { /* Should never happen since we send PATH_MAX */ /* FIXME: can we save some information here? */ |
def575434
|
1576 |
audit_log_string(ab, "<too_long>"); |
5600b8927
|
1577 |
} else |
168b71739
|
1578 |
audit_log_untrustedstring(ab, p); |
44707fdf5
|
1579 |
kfree(pathname); |
1da177e4c
|
1580 |
} |
4d3fb709b
|
1581 1582 |
void audit_log_session_info(struct audit_buffer *ab) { |
4440e8548
|
1583 |
unsigned int sessionid = audit_get_sessionid(current); |
4d3fb709b
|
1584 |
uid_t auid = from_kuid(&init_user_ns, audit_get_loginuid(current)); |
b8f89caaf
|
1585 |
audit_log_format(ab, " auid=%u ses=%u", auid, sessionid); |
4d3fb709b
|
1586 |
} |
9d9609851
|
1587 1588 1589 1590 1591 1592 1593 1594 |
void audit_log_key(struct audit_buffer *ab, char *key) { audit_log_format(ab, " key="); if (key) audit_log_untrustedstring(ab, key); else audit_log_format(ab, "(null)"); } |
b24a30a73
|
1595 1596 1597 1598 1599 1600 1601 |
void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *cap) { int i; audit_log_format(ab, " %s=", prefix); CAP_FOR_EACH_U32(i) { audit_log_format(ab, "%08x", |
7d8b6c637
|
1602 |
cap->cap[CAP_LAST_U32 - i]); |
b24a30a73
|
1603 1604 |
} } |
691e6d59d
|
1605 |
static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name) |
b24a30a73
|
1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 |
{ kernel_cap_t *perm = &name->fcap.permitted; kernel_cap_t *inh = &name->fcap.inheritable; int log = 0; if (!cap_isclear(*perm)) { audit_log_cap(ab, "cap_fp", perm); log = 1; } if (!cap_isclear(*inh)) { audit_log_cap(ab, "cap_fi", inh); log = 1; } if (log) audit_log_format(ab, " cap_fe=%d cap_fver=%x", name->fcap.fE, name->fcap_ver); } static inline int audit_copy_fcaps(struct audit_names *name, const struct dentry *dentry) { struct cpu_vfs_cap_data caps; int rc; if (!dentry) return 0; rc = get_vfs_caps_from_disk(dentry, &caps); if (rc) return rc; name->fcap.permitted = caps.permitted; name->fcap.inheritable = caps.inheritable; name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE); name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT; return 0; } /* Copy inode data into an audit_names. */ void audit_copy_inode(struct audit_names *name, const struct dentry *dentry, const struct inode *inode) { name->ino = inode->i_ino; name->dev = inode->i_sb->s_dev; name->mode = inode->i_mode; name->uid = inode->i_uid; name->gid = inode->i_gid; name->rdev = inode->i_rdev; security_inode_getsecid(inode, &name->osid); audit_copy_fcaps(name, dentry); } /** * audit_log_name - produce AUDIT_PATH record from struct audit_names * @context: audit_context for the task * @n: audit_names structure with reportable details * @path: optional path to report instead of audit_names->name * @record_num: record number to report when handling a list of names * @call_panic: optional pointer to int that will be updated if secid fails */ void audit_log_name(struct audit_context *context, struct audit_names *n, struct path *path, int record_num, int *call_panic) { struct audit_buffer *ab; ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH); if (!ab) return; audit_log_format(ab, "item=%d", record_num); if (path) audit_log_d_path(ab, " name=", path); else if (n->name) { switch (n->name_len) { case AUDIT_NAME_FULL: /* log the full path */ audit_log_format(ab, " name="); audit_log_untrustedstring(ab, n->name->name); break; case 0: /* name was specified as a relative path and the * directory component is the cwd */ audit_log_d_path(ab, " name=", &context->pwd); break; default: /* log the name's directory component */ audit_log_format(ab, " name="); audit_log_n_untrustedstring(ab, n->name->name, n->name_len); } } else audit_log_format(ab, " name=(null)"); |
425afcff1
|
1701 |
if (n->ino != AUDIT_INO_UNSET) |
b24a30a73
|
1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 |
audit_log_format(ab, " inode=%lu" " dev=%02x:%02x mode=%#ho" " ouid=%u ogid=%u rdev=%02x:%02x", n->ino, MAJOR(n->dev), MINOR(n->dev), n->mode, from_kuid(&init_user_ns, n->uid), from_kgid(&init_user_ns, n->gid), MAJOR(n->rdev), MINOR(n->rdev)); |
b24a30a73
|
1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 |
if (n->osid != 0) { char *ctx = NULL; u32 len; if (security_secid_to_secctx( n->osid, &ctx, &len)) { audit_log_format(ab, " osid=%u", n->osid); if (call_panic) *call_panic = 2; } else { audit_log_format(ab, " obj=%s", ctx); security_release_secctx(ctx, len); } } |
d3aea84a4
|
1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 |
/* log the audit_names record type */ audit_log_format(ab, " nametype="); switch(n->type) { case AUDIT_TYPE_NORMAL: audit_log_format(ab, "NORMAL"); break; case AUDIT_TYPE_PARENT: audit_log_format(ab, "PARENT"); break; case AUDIT_TYPE_CHILD_DELETE: audit_log_format(ab, "DELETE"); break; case AUDIT_TYPE_CHILD_CREATE: audit_log_format(ab, "CREATE"); break; default: audit_log_format(ab, "UNKNOWN"); break; } |
b24a30a73
|
1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 |
audit_log_fcaps(ab, n); audit_log_end(ab); } int audit_log_task_context(struct audit_buffer *ab) { char *ctx = NULL; unsigned len; int error; u32 sid; security_task_getsecid(current, &sid); if (!sid) return 0; error = security_secid_to_secctx(sid, &ctx, &len); if (error) { if (error != -EINVAL) goto error_path; return 0; } audit_log_format(ab, " subj=%s", ctx); security_release_secctx(ctx, len); return 0; error_path: audit_panic("error in audit_log_task_context"); return error; } EXPORT_SYMBOL(audit_log_task_context); |
4766b199e
|
1776 1777 1778 |
void audit_log_d_path_exe(struct audit_buffer *ab, struct mm_struct *mm) { |
5b2825527
|
1779 1780 1781 1782 |
struct file *exe_file; if (!mm) goto out_null; |
4766b199e
|
1783 |
|
5b2825527
|
1784 1785 1786 1787 1788 1789 1790 1791 1792 |
exe_file = get_mm_exe_file(mm); if (!exe_file) goto out_null; audit_log_d_path(ab, " exe=", &exe_file->f_path); fput(exe_file); return; out_null: audit_log_format(ab, " exe=(null)"); |
4766b199e
|
1793 |
} |
b24a30a73
|
1794 1795 1796 |
void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk) { const struct cred *cred; |
9eab339b1
|
1797 |
char comm[sizeof(tsk->comm)]; |
b24a30a73
|
1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 |
char *tty; if (!ab) return; /* tsk == current */ cred = current_cred(); spin_lock_irq(&tsk->sighand->siglock); if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name) tty = tsk->signal->tty->name; else tty = "(none)"; spin_unlock_irq(&tsk->sighand->siglock); audit_log_format(ab, |
c92cdeb45
|
1814 |
" ppid=%d pid=%d auid=%u uid=%u gid=%u" |
b24a30a73
|
1815 |
" euid=%u suid=%u fsuid=%u" |
2f2ad1013
|
1816 |
" egid=%u sgid=%u fsgid=%u tty=%s ses=%u", |
c92cdeb45
|
1817 |
task_ppid_nr(tsk), |
f1dc4867f
|
1818 |
task_pid_nr(tsk), |
b24a30a73
|
1819 1820 1821 1822 1823 1824 1825 1826 1827 |
from_kuid(&init_user_ns, audit_get_loginuid(tsk)), from_kuid(&init_user_ns, cred->uid), from_kgid(&init_user_ns, cred->gid), from_kuid(&init_user_ns, cred->euid), from_kuid(&init_user_ns, cred->suid), from_kuid(&init_user_ns, cred->fsuid), from_kgid(&init_user_ns, cred->egid), from_kgid(&init_user_ns, cred->sgid), from_kgid(&init_user_ns, cred->fsgid), |
2f2ad1013
|
1828 |
tty, audit_get_sessionid(tsk)); |
b24a30a73
|
1829 |
|
b24a30a73
|
1830 |
audit_log_format(ab, " comm="); |
9eab339b1
|
1831 |
audit_log_untrustedstring(ab, get_task_comm(comm, tsk)); |
b24a30a73
|
1832 |
|
4766b199e
|
1833 |
audit_log_d_path_exe(ab, tsk->mm); |
b24a30a73
|
1834 1835 1836 |
audit_log_task_context(ab); } EXPORT_SYMBOL(audit_log_task_info); |
b0dd25a82
|
1837 |
/** |
a51d9eaa4
|
1838 |
* audit_log_link_denied - report a link restriction denial |
220119647
|
1839 |
* @operation: specific link operation |
a51d9eaa4
|
1840 1841 1842 1843 1844 |
* @link: the path that triggered the restriction */ void audit_log_link_denied(const char *operation, struct path *link) { struct audit_buffer *ab; |
b24a30a73
|
1845 1846 1847 1848 1849 |
struct audit_names *name; name = kzalloc(sizeof(*name), GFP_NOFS); if (!name) return; |
a51d9eaa4
|
1850 |
|
b24a30a73
|
1851 |
/* Generate AUDIT_ANOM_LINK with subject, operation, outcome. */ |
a51d9eaa4
|
1852 1853 |
ab = audit_log_start(current->audit_context, GFP_KERNEL, AUDIT_ANOM_LINK); |
d1c7d97ad
|
1854 |
if (!ab) |
b24a30a73
|
1855 1856 1857 1858 |
goto out; audit_log_format(ab, "op=%s", operation); audit_log_task_info(ab, current); audit_log_format(ab, " res=0"); |
a51d9eaa4
|
1859 |
audit_log_end(ab); |
b24a30a73
|
1860 1861 1862 |
/* Generate AUDIT_PATH record with object. */ name->type = AUDIT_TYPE_NORMAL; |
3b362157b
|
1863 |
audit_copy_inode(name, link->dentry, d_backing_inode(link->dentry)); |
b24a30a73
|
1864 1865 1866 |
audit_log_name(current->audit_context, name, link, 0, NULL); out: kfree(name); |
a51d9eaa4
|
1867 1868 1869 |
} /** |
b0dd25a82
|
1870 1871 1872 |
* audit_log_end - end one audit record * @ab: the audit_buffer * |
451f92163
|
1873 1874 1875 1876 |
* netlink_unicast() cannot be called inside an irq context because it blocks * (last arg, flags, is not set to MSG_DONTWAIT), so the audit buffer is placed * on a queue and a tasklet is scheduled to remove them from the queue outside * the irq context. May be called in any context. |
b0dd25a82
|
1877 |
*/ |
b7d112581
|
1878 |
void audit_log_end(struct audit_buffer *ab) |
1da177e4c
|
1879 |
{ |
1da177e4c
|
1880 1881 1882 1883 1884 |
if (!ab) return; if (!audit_rate_check()) { audit_log_lost("rate limit exceeded"); } else { |
8d07a67cf
|
1885 |
struct nlmsghdr *nlh = nlmsg_hdr(ab->skb); |
451f92163
|
1886 |
|
54e05eddb
|
1887 |
nlh->nlmsg_len = ab->skb->len; |
54dc77d97
|
1888 |
kauditd_send_multicast_skb(ab->skb, ab->gfp_mask); |
451f92163
|
1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 |
/* * The original kaudit unicast socket sends up messages with * nlmsg_len set to the payload length rather than the entire * message length. This breaks the standard set by netlink. * The existing auditd daemon assumes this breakage. Fixing * this would require co-ordinating a change in the established * protocol between the kaudit kernel subsystem and the auditd * userspace code. */ |
54e05eddb
|
1899 |
nlh->nlmsg_len -= NLMSG_HDRLEN; |
f3d357b09
|
1900 |
|
b7d112581
|
1901 |
if (audit_pid) { |
b7d112581
|
1902 |
skb_queue_tail(&audit_skb_queue, ab->skb); |
b7d112581
|
1903 |
wake_up_interruptible(&kauditd_wait); |
f3d357b09
|
1904 |
} else { |
038cbcf65
|
1905 |
audit_printk_skb(ab->skb); |
b7d112581
|
1906 |
} |
f3d357b09
|
1907 |
ab->skb = NULL; |
1da177e4c
|
1908 |
} |
16e1904e6
|
1909 |
audit_buffer_free(ab); |
1da177e4c
|
1910 |
} |
b0dd25a82
|
1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 |
/** * audit_log - Log an audit record * @ctx: audit context * @gfp_mask: type of allocation * @type: audit message type * @fmt: format string to use * @...: variable parameters matching the format string * * This is a convenience function that calls audit_log_start, * audit_log_vformat, and audit_log_end. It may be called * in any context. */ |
5600b8927
|
1923 |
void audit_log(struct audit_context *ctx, gfp_t gfp_mask, int type, |
9ad9ad385
|
1924 |
const char *fmt, ...) |
1da177e4c
|
1925 1926 1927 |
{ struct audit_buffer *ab; va_list args; |
9ad9ad385
|
1928 |
ab = audit_log_start(ctx, gfp_mask, type); |
1da177e4c
|
1929 1930 1931 1932 1933 1934 1935 |
if (ab) { va_start(args, fmt); audit_log_vformat(ab, fmt, args); va_end(args); audit_log_end(ab); } } |
bf45da97a
|
1936 |
|
131ad62d8
|
1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 |
#ifdef CONFIG_SECURITY /** * audit_log_secctx - Converts and logs SELinux context * @ab: audit_buffer * @secid: security number * * This is a helper function that calls security_secid_to_secctx to convert * secid to secctx and then adds the (converted) SELinux context to the audit * log by calling audit_log_format, thus also preventing leak of internal secid * to userspace. If secid cannot be converted audit_panic is called. */ void audit_log_secctx(struct audit_buffer *ab, u32 secid) { u32 len; char *secctx; if (security_secid_to_secctx(secid, &secctx, &len)) { audit_panic("Cannot convert secid to context"); } else { audit_log_format(ab, " obj=%s", secctx); security_release_secctx(secctx, len); } } EXPORT_SYMBOL(audit_log_secctx); #endif |
bf45da97a
|
1962 1963 1964 1965 |
EXPORT_SYMBOL(audit_log_start); EXPORT_SYMBOL(audit_log_end); EXPORT_SYMBOL(audit_log_format); EXPORT_SYMBOL(audit_log); |