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kernel/audit.c
53.3 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/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; |
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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(); |
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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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{ struct sk_buff *skb; |
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|
473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 |
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 */ |
d865e573b
|
489 |
consume_skb(skb); |
b551d1d98
|
490 |
} |
97a41e261
|
491 |
static int kauditd_thread(void *dummy) |
b7d112581
|
492 |
{ |
831441862
|
493 |
set_freezable(); |
4899b8b16
|
494 |
while (!kthread_should_stop()) { |
3320c5133
|
495 |
struct sk_buff *skb; |
3320c5133
|
496 |
|
b551d1d98
|
497 |
flush_hold_queue(); |
f3d357b09
|
498 |
|
b7d112581
|
499 |
skb = skb_dequeue(&audit_skb_queue); |
db8973194
|
500 |
|
b7d112581
|
501 |
if (skb) { |
1194b994b
|
502 503 |
if (!audit_backlog_limit || (skb_queue_len(&audit_skb_queue) <= audit_backlog_limit)) |
db8973194
|
504 |
wake_up(&audit_backlog_wait); |
f3d357b09
|
505 506 |
if (audit_pid) kauditd_send_skb(skb); |
038cbcf65
|
507 508 |
else audit_printk_skb(skb); |
3320c5133
|
509 510 |
continue; } |
b7d112581
|
511 |
|
6b55fc63f
|
512 |
wait_event_freezable(kauditd_wait, skb_queue_len(&audit_skb_queue)); |
b7d112581
|
513 |
} |
4899b8b16
|
514 |
return 0; |
b7d112581
|
515 |
} |
9044e6bca
|
516 517 518 |
int audit_send_list(void *_dest) { struct audit_netlink_list *dest = _dest; |
9044e6bca
|
519 |
struct sk_buff *skb; |
48095d991
|
520 |
struct net *net = dest->net; |
33faba7fa
|
521 |
struct audit_net *aunet = net_generic(net, audit_net_id); |
9044e6bca
|
522 523 |
/* wait for parent to finish and send an ACK */ |
f368c07d7
|
524 525 |
mutex_lock(&audit_cmd_mutex); mutex_unlock(&audit_cmd_mutex); |
9044e6bca
|
526 527 |
while ((skb = __skb_dequeue(&dest->q)) != NULL) |
33faba7fa
|
528 |
netlink_unicast(aunet->nlsk, skb, dest->portid, 0); |
9044e6bca
|
529 |
|
48095d991
|
530 |
put_net(net); |
9044e6bca
|
531 532 533 534 |
kfree(dest); return 0; } |
f9441639e
|
535 |
struct sk_buff *audit_make_reply(__u32 portid, int seq, int type, int done, |
b8800aa5d
|
536 |
int multi, const void *payload, int size) |
9044e6bca
|
537 538 539 |
{ struct sk_buff *skb; struct nlmsghdr *nlh; |
9044e6bca
|
540 541 542 |
void *data; int flags = multi ? NLM_F_MULTI : 0; int t = done ? NLMSG_DONE : type; |
ee080e6ce
|
543 |
skb = nlmsg_new(size, GFP_KERNEL); |
9044e6bca
|
544 545 |
if (!skb) return NULL; |
f9441639e
|
546 |
nlh = nlmsg_put(skb, portid, seq, t, size, flags); |
c64e66c67
|
547 548 549 |
if (!nlh) goto out_kfree_skb; data = nlmsg_data(nlh); |
9044e6bca
|
550 551 |
memcpy(data, payload, size); return skb; |
c64e66c67
|
552 553 |
out_kfree_skb: kfree_skb(skb); |
9044e6bca
|
554 555 |
return NULL; } |
f09ac9db2
|
556 557 558 |
static int audit_send_reply_thread(void *arg) { struct audit_reply *reply = (struct audit_reply *)arg; |
48095d991
|
559 |
struct net *net = reply->net; |
33faba7fa
|
560 |
struct audit_net *aunet = net_generic(net, audit_net_id); |
f09ac9db2
|
561 562 563 564 565 566 |
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
|
567 |
netlink_unicast(aunet->nlsk , reply->skb, reply->portid, 0); |
48095d991
|
568 |
put_net(net); |
f09ac9db2
|
569 570 571 |
kfree(reply); return 0; } |
b0dd25a82
|
572 573 |
/** * audit_send_reply - send an audit reply message via netlink |
d211f177b
|
574 |
* @request_skb: skb of request we are replying to (used to target the reply) |
b0dd25a82
|
575 576 577 578 579 580 581 |
* @seq: sequence number * @type: audit message type * @done: done (last) flag * @multi: multi-part message flag * @payload: payload data * @size: payload size * |
f9441639e
|
582 |
* Allocates an skb, builds the netlink message, and sends it to the port id. |
b0dd25a82
|
583 584 |
* No failure notifications. */ |
6f285b19d
|
585 |
static void audit_send_reply(struct sk_buff *request_skb, int seq, int type, int done, |
f9441639e
|
586 |
int multi, const void *payload, int size) |
1da177e4c
|
587 |
{ |
6f285b19d
|
588 589 |
u32 portid = NETLINK_CB(request_skb).portid; struct net *net = sock_net(NETLINK_CB(request_skb).sk); |
f09ac9db2
|
590 591 592 593 594 595 596 |
struct sk_buff *skb; struct task_struct *tsk; struct audit_reply *reply = kmalloc(sizeof(struct audit_reply), GFP_KERNEL); if (!reply) return; |
f9441639e
|
597 |
skb = audit_make_reply(portid, seq, type, done, multi, payload, size); |
1da177e4c
|
598 |
if (!skb) |
fcaf1eb86
|
599 |
goto out; |
f09ac9db2
|
600 |
|
6f285b19d
|
601 |
reply->net = get_net(net); |
f9441639e
|
602 |
reply->portid = portid; |
f09ac9db2
|
603 604 605 |
reply->skb = skb; tsk = kthread_run(audit_send_reply_thread, reply, "audit_send_reply"); |
fcaf1eb86
|
606 607 608 609 610 |
if (!IS_ERR(tsk)) return; kfree_skb(skb); out: kfree(reply); |
1da177e4c
|
611 612 613 614 615 616 |
} /* * Check for appropriate CAP_AUDIT_ capabilities on incoming audit * control messages. */ |
c7bdb545d
|
617 |
static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type) |
1da177e4c
|
618 619 |
{ int err = 0; |
5a3cb3b6c
|
620 |
/* Only support initial user namespace for now. */ |
aa4af831b
|
621 622 623 624 625 626 627 628 629 630 |
/* * 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
|
631 |
if (current_user_ns() != &init_user_ns) |
aa4af831b
|
632 |
return -ECONNREFUSED; |
34e36d8ec
|
633 |
|
1da177e4c
|
634 |
switch (msg_type) { |
1da177e4c
|
635 |
case AUDIT_LIST: |
1da177e4c
|
636 637 |
case AUDIT_ADD: case AUDIT_DEL: |
189009091
|
638 639 640 |
return -EOPNOTSUPP; case AUDIT_GET: case AUDIT_SET: |
b0fed4021
|
641 642 |
case AUDIT_GET_FEATURE: case AUDIT_SET_FEATURE: |
189009091
|
643 644 |
case AUDIT_LIST_RULES: case AUDIT_ADD_RULE: |
93315ed6d
|
645 |
case AUDIT_DEL_RULE: |
c2f0c7c35
|
646 |
case AUDIT_SIGNAL_INFO: |
522ed7767
|
647 648 |
case AUDIT_TTY_GET: case AUDIT_TTY_SET: |
74c3cbe33
|
649 650 |
case AUDIT_TRIM: case AUDIT_MAKE_EQUIV: |
5a3cb3b6c
|
651 652 |
/* Only support auditd and auditctl in initial pid namespace * for now. */ |
5985de675
|
653 |
if (task_active_pid_ns(current) != &init_pid_ns) |
5a3cb3b6c
|
654 |
return -EPERM; |
90f62cf30
|
655 |
if (!netlink_capable(skb, CAP_AUDIT_CONTROL)) |
1da177e4c
|
656 657 |
err = -EPERM; break; |
05474106a
|
658 |
case AUDIT_USER: |
039b6b3ed
|
659 660 |
case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG: case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2: |
90f62cf30
|
661 |
if (!netlink_capable(skb, CAP_AUDIT_WRITE)) |
1da177e4c
|
662 663 664 665 666 667 668 669 |
err = -EPERM; break; default: /* bad msg */ err = -EINVAL; } return err; } |
233a68667
|
670 |
static void audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type) |
50397bd1e
|
671 |
{ |
dc9eb698f
|
672 |
uid_t uid = from_kuid(&init_user_ns, current_uid()); |
f1dc4867f
|
673 |
pid_t pid = task_tgid_nr(current); |
50397bd1e
|
674 |
|
0868a5e15
|
675 |
if (!audit_enabled && msg_type != AUDIT_USER_AVC) { |
50397bd1e
|
676 |
*ab = NULL; |
233a68667
|
677 |
return; |
50397bd1e
|
678 679 680 |
} *ab = audit_log_start(NULL, GFP_KERNEL, msg_type); |
0644ec0cc
|
681 |
if (unlikely(!*ab)) |
233a68667
|
682 |
return; |
f1dc4867f
|
683 |
audit_log_format(*ab, "pid=%d uid=%u", pid, uid); |
4d3fb709b
|
684 |
audit_log_session_info(*ab); |
b122c3767
|
685 |
audit_log_task_context(*ab); |
50397bd1e
|
686 |
} |
b0fed4021
|
687 688 689 690 691 692 693 694 695 696 697 |
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
|
698 |
audit_send_reply(skb, seq, AUDIT_GET_FEATURE, 0, 0, &af, sizeof(af)); |
b0fed4021
|
699 700 701 702 703 704 705 706 |
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
|
707 708 |
if (audit_enabled == AUDIT_OFF) return; |
b0fed4021
|
709 |
ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_FEATURE_CHANGE); |
ad2ac2632
|
710 |
audit_log_task_info(ab, current); |
897f1acbb
|
711 |
audit_log_format(ab, " feature=%s old=%u new=%u old_lock=%u new_lock=%u res=%d", |
b0fed4021
|
712 713 714 715 716 717 718 719 720 |
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
|
721 |
BUILD_BUG_ON(AUDIT_LAST_FEATURE + 1 > ARRAY_SIZE(audit_feature_names)); |
b0fed4021
|
722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 |
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
|
740 |
if (old_lock && (new_feature != old_feature)) { |
b0fed4021
|
741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 |
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; } |
133e1e5ac
|
773 774 775 776 777 778 779 780 781 |
static int audit_replace(pid_t pid) { struct sk_buff *skb = audit_make_reply(0, 0, AUDIT_REPLACE, 0, 0, &pid, sizeof(pid)); if (!skb) return -ENOMEM; return netlink_unicast(audit_sock, skb, audit_nlk_portid, 0); } |
1da177e4c
|
782 783 |
static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) { |
dc9eb698f
|
784 |
u32 seq; |
1da177e4c
|
785 |
void *data; |
1da177e4c
|
786 |
int err; |
c04049939
|
787 |
struct audit_buffer *ab; |
1da177e4c
|
788 |
u16 msg_type = nlh->nlmsg_type; |
e1396065e
|
789 |
struct audit_sig_info *sig_data; |
50397bd1e
|
790 |
char *ctx = NULL; |
e1396065e
|
791 |
u32 len; |
1da177e4c
|
792 |
|
c7bdb545d
|
793 |
err = audit_netlink_ok(skb, msg_type); |
1da177e4c
|
794 795 |
if (err) return err; |
b0dd25a82
|
796 797 |
/* As soon as there's any sign of userspace auditd, * start kauditd to talk to it */ |
13f51e1c3
|
798 |
if (!kauditd_task) { |
b7d112581
|
799 |
kauditd_task = kthread_run(kauditd_thread, NULL, "kauditd"); |
13f51e1c3
|
800 801 802 803 804 |
if (IS_ERR(kauditd_task)) { err = PTR_ERR(kauditd_task); kauditd_task = NULL; return err; } |
b7d112581
|
805 |
} |
1da177e4c
|
806 |
seq = nlh->nlmsg_seq; |
c64e66c67
|
807 |
data = nlmsg_data(nlh); |
1da177e4c
|
808 809 |
switch (msg_type) { |
09f883a90
|
810 811 812 813 814 815 816 817 818 819 |
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
|
820 |
s.feature_bitmap = AUDIT_FEATURE_BITMAP_ALL; |
a77ed4e56
|
821 |
s.backlog_wait_time = audit_backlog_wait_time_master; |
6f285b19d
|
822 |
audit_send_reply(skb, seq, AUDIT_GET, 0, 0, &s, sizeof(s)); |
1da177e4c
|
823 |
break; |
09f883a90
|
824 825 826 827 828 829 830 831 |
} 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
|
832 833 |
if (err < 0) return err; |
1da177e4c
|
834 |
} |
09f883a90
|
835 836 |
if (s.mask & AUDIT_STATUS_FAILURE) { err = audit_set_failure(s.failure); |
20c6aaa39
|
837 838 |
if (err < 0) return err; |
1da177e4c
|
839 |
} |
09f883a90
|
840 841 |
if (s.mask & AUDIT_STATUS_PID) { int new_pid = s.pid; |
133e1e5ac
|
842 |
pid_t requesting_pid = task_tgid_vnr(current); |
1a6b9f231
|
843 |
|
935c9e7ff
|
844 845 |
if ((!new_pid) && (requesting_pid != audit_pid)) { audit_log_config_change("audit_pid", new_pid, audit_pid, 0); |
34eab0a7c
|
846 |
return -EACCES; |
935c9e7ff
|
847 |
} |
133e1e5ac
|
848 |
if (audit_pid && new_pid && |
935c9e7ff
|
849 850 |
audit_replace(requesting_pid) != -ECONNREFUSED) { audit_log_config_change("audit_pid", new_pid, audit_pid, 0); |
133e1e5ac
|
851 |
return -EEXIST; |
935c9e7ff
|
852 |
} |
1a6b9f231
|
853 |
if (audit_enabled != AUDIT_OFF) |
dc9eb698f
|
854 |
audit_log_config_change("audit_pid", new_pid, audit_pid, 1); |
1a6b9f231
|
855 |
audit_pid = new_pid; |
15e473046
|
856 |
audit_nlk_portid = NETLINK_CB(skb).portid; |
de92fc97e
|
857 |
audit_sock = skb->sk; |
1da177e4c
|
858 |
} |
09f883a90
|
859 860 |
if (s.mask & AUDIT_STATUS_RATE_LIMIT) { err = audit_set_rate_limit(s.rate_limit); |
20c6aaa39
|
861 862 863 |
if (err < 0) return err; } |
51cc83f02
|
864 |
if (s.mask & AUDIT_STATUS_BACKLOG_LIMIT) { |
09f883a90
|
865 |
err = audit_set_backlog_limit(s.backlog_limit); |
51cc83f02
|
866 867 868 |
if (err < 0) return err; } |
3f0c5fad8
|
869 870 871 |
if (s.mask & AUDIT_STATUS_BACKLOG_WAIT_TIME) { if (sizeof(s) > (size_t)nlh->nlmsg_len) return -EINVAL; |
724e7bfcc
|
872 |
if (s.backlog_wait_time > 10*AUDIT_BACKLOG_WAIT_TIME) |
3f0c5fad8
|
873 874 875 876 |
return -EINVAL; err = audit_set_backlog_wait_time(s.backlog_wait_time); if (err < 0) return err; |
51cc83f02
|
877 |
} |
1da177e4c
|
878 |
break; |
09f883a90
|
879 |
} |
b0fed4021
|
880 881 882 883 884 885 886 887 888 889 |
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
|
890 |
case AUDIT_USER: |
039b6b3ed
|
891 892 |
case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG: case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2: |
4a4cd633b
|
893 894 |
if (!audit_enabled && msg_type != AUDIT_USER_AVC) return 0; |
62062cf8a
|
895 |
err = audit_filter_user(msg_type); |
724e4fcc8
|
896 |
if (err == 1) { /* match or error */ |
4a4cd633b
|
897 |
err = 0; |
522ed7767
|
898 |
if (msg_type == AUDIT_USER_TTY) { |
37282a779
|
899 |
err = tty_audit_push(); |
522ed7767
|
900 901 902 |
if (err) break; } |
1b7b533f6
|
903 |
mutex_unlock(&audit_cmd_mutex); |
dc9eb698f
|
904 |
audit_log_common_recv_msg(&ab, msg_type); |
50397bd1e
|
905 |
if (msg_type != AUDIT_USER_TTY) |
b50eba7e2
|
906 907 |
audit_log_format(ab, " msg='%.*s'", AUDIT_MESSAGE_TEXT_MAX, |
50397bd1e
|
908 909 910 |
(char *)data); else { int size; |
f7616102d
|
911 |
audit_log_format(ab, " data="); |
50397bd1e
|
912 |
size = nlmsg_len(nlh); |
55ad2f8d3
|
913 914 915 |
if (size > 0 && ((unsigned char *)data)[size - 1] == '\0') size--; |
b556f8ad5
|
916 |
audit_log_n_untrustedstring(ab, data, size); |
4a4cd633b
|
917 |
} |
f9441639e
|
918 |
audit_set_portid(ab, NETLINK_CB(skb).portid); |
50397bd1e
|
919 |
audit_log_end(ab); |
1b7b533f6
|
920 |
mutex_lock(&audit_cmd_mutex); |
0f45aa18e
|
921 |
} |
1da177e4c
|
922 |
break; |
93315ed6d
|
923 924 925 926 |
case AUDIT_ADD_RULE: case AUDIT_DEL_RULE: if (nlmsg_len(nlh) < sizeof(struct audit_rule_data)) return -EINVAL; |
1a6b9f231
|
927 |
if (audit_enabled == AUDIT_LOCKED) { |
dc9eb698f
|
928 929 |
audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE); audit_log_format(ab, " audit_enabled=%d res=0", audit_enabled); |
50397bd1e
|
930 |
audit_log_end(ab); |
6a01b07fa
|
931 932 |
return -EPERM; } |
ce0d9f046
|
933 |
err = audit_rule_change(msg_type, NETLINK_CB(skb).portid, |
dc9eb698f
|
934 |
seq, data, nlmsg_len(nlh)); |
1da177e4c
|
935 |
break; |
ce0d9f046
|
936 |
case AUDIT_LIST_RULES: |
6f285b19d
|
937 |
err = audit_list_rules_send(skb, seq); |
ce0d9f046
|
938 |
break; |
74c3cbe33
|
939 940 |
case AUDIT_TRIM: audit_trim_trees(); |
dc9eb698f
|
941 |
audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE); |
74c3cbe33
|
942 943 944 945 946 947 |
audit_log_format(ab, " op=trim res=1"); audit_log_end(ab); break; case AUDIT_MAKE_EQUIV: { void *bufp = data; u32 sizes[2]; |
7719e437f
|
948 |
size_t msglen = nlmsg_len(nlh); |
74c3cbe33
|
949 950 951 |
char *old, *new; err = -EINVAL; |
7719e437f
|
952 |
if (msglen < 2 * sizeof(u32)) |
74c3cbe33
|
953 954 955 |
break; memcpy(sizes, bufp, 2 * sizeof(u32)); bufp += 2 * sizeof(u32); |
7719e437f
|
956 957 |
msglen -= 2 * sizeof(u32); old = audit_unpack_string(&bufp, &msglen, sizes[0]); |
74c3cbe33
|
958 959 960 961 |
if (IS_ERR(old)) { err = PTR_ERR(old); break; } |
7719e437f
|
962 |
new = audit_unpack_string(&bufp, &msglen, sizes[1]); |
74c3cbe33
|
963 964 965 966 967 968 969 |
if (IS_ERR(new)) { err = PTR_ERR(new); kfree(old); break; } /* OK, here comes... */ err = audit_tag_tree(old, new); |
dc9eb698f
|
970 |
audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE); |
50397bd1e
|
971 |
|
74c3cbe33
|
972 973 974 975 976 977 978 979 980 981 |
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
|
982 |
case AUDIT_SIGNAL_INFO: |
939cbf260
|
983 984 985 986 987 988 |
len = 0; if (audit_sig_sid) { err = security_secid_to_secctx(audit_sig_sid, &ctx, &len); if (err) return err; } |
e1396065e
|
989 990 |
sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL); if (!sig_data) { |
939cbf260
|
991 992 |
if (audit_sig_sid) security_release_secctx(ctx, len); |
e1396065e
|
993 994 |
return -ENOMEM; } |
cca080d9b
|
995 |
sig_data->uid = from_kuid(&init_user_ns, audit_sig_uid); |
e1396065e
|
996 |
sig_data->pid = audit_sig_pid; |
939cbf260
|
997 998 999 1000 |
if (audit_sig_sid) { memcpy(sig_data->ctx, ctx, len); security_release_secctx(ctx, len); } |
6f285b19d
|
1001 1002 |
audit_send_reply(skb, seq, AUDIT_SIGNAL_INFO, 0, 0, sig_data, sizeof(*sig_data) + len); |
e1396065e
|
1003 |
kfree(sig_data); |
c2f0c7c35
|
1004 |
break; |
522ed7767
|
1005 1006 |
case AUDIT_TTY_GET: { struct audit_tty_status s; |
2e28d38ae
|
1007 |
unsigned int t; |
8aa14b649
|
1008 |
|
2e28d38ae
|
1009 1010 1011 |
t = READ_ONCE(current->signal->audit_tty); s.enabled = t & AUDIT_TTY_ENABLE; s.log_passwd = !!(t & AUDIT_TTY_LOG_PASSWD); |
8aa14b649
|
1012 |
|
6f285b19d
|
1013 |
audit_send_reply(skb, seq, AUDIT_TTY_GET, 0, 0, &s, sizeof(s)); |
522ed7767
|
1014 1015 1016 |
break; } case AUDIT_TTY_SET: { |
a06e56b2a
|
1017 |
struct audit_tty_status s, old; |
a06e56b2a
|
1018 |
struct audit_buffer *ab; |
2e28d38ae
|
1019 |
unsigned int t; |
0e23bacca
|
1020 1021 1022 1023 1024 1025 1026 1027 |
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
|
1028 |
|
2e28d38ae
|
1029 1030 1031 1032 1033 |
if (err) t = READ_ONCE(current->signal->audit_tty); else { t = s.enabled | (-s.log_passwd & AUDIT_TTY_LOG_PASSWD); t = xchg(¤t->signal->audit_tty, t); |
0e23bacca
|
1034 |
} |
2e28d38ae
|
1035 1036 |
old.enabled = t & AUDIT_TTY_ENABLE; old.log_passwd = !!(t & AUDIT_TTY_LOG_PASSWD); |
522ed7767
|
1037 |
|
a06e56b2a
|
1038 |
audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE); |
1ce319f11
|
1039 1040 1041 1042 |
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
|
1043 |
audit_log_end(ab); |
522ed7767
|
1044 1045 |
break; } |
1da177e4c
|
1046 1047 1048 1049 1050 1051 1052 |
default: err = -EINVAL; break; } return err < 0 ? err : 0; } |
b0dd25a82
|
1053 |
/* |
ea7ae60bf
|
1054 1055 |
* Get message from skb. Each message is processed by audit_receive_msg. * Malformed skbs with wrong length are discarded silently. |
b0dd25a82
|
1056 |
*/ |
2a0a6ebee
|
1057 |
static void audit_receive_skb(struct sk_buff *skb) |
1da177e4c
|
1058 |
{ |
ea7ae60bf
|
1059 1060 |
struct nlmsghdr *nlh; /* |
941912133
|
1061 |
* len MUST be signed for nlmsg_next to be able to dec it below 0 |
ea7ae60bf
|
1062 1063 1064 1065 1066 1067 1068 |
* if the nlmsg_len was not aligned */ int len; int err; nlh = nlmsg_hdr(skb); len = skb->len; |
941912133
|
1069 |
while (nlmsg_ok(nlh, len)) { |
ea7ae60bf
|
1070 1071 1072 |
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
|
1073 |
netlink_ack(skb, nlh, err); |
ea7ae60bf
|
1074 |
|
2851da570
|
1075 |
nlh = nlmsg_next(nlh, &len); |
1da177e4c
|
1076 |
} |
1da177e4c
|
1077 1078 1079 |
} /* Receive messages from netlink socket. */ |
cd40b7d39
|
1080 |
static void audit_receive(struct sk_buff *skb) |
1da177e4c
|
1081 |
{ |
f368c07d7
|
1082 |
mutex_lock(&audit_cmd_mutex); |
cd40b7d39
|
1083 |
audit_receive_skb(skb); |
f368c07d7
|
1084 |
mutex_unlock(&audit_cmd_mutex); |
1da177e4c
|
1085 |
} |
3a101b8de
|
1086 |
/* Run custom bind function on netlink socket group connect or bind requests. */ |
023e2cfa3
|
1087 |
static int audit_bind(struct net *net, int group) |
3a101b8de
|
1088 1089 1090 1091 1092 1093 |
{ if (!capable(CAP_AUDIT_READ)) return -EPERM; return 0; } |
33faba7fa
|
1094 |
static int __net_init audit_net_init(struct net *net) |
1da177e4c
|
1095 |
{ |
a31f2d17b
|
1096 1097 |
struct netlink_kernel_cfg cfg = { .input = audit_receive, |
3a101b8de
|
1098 |
.bind = audit_bind, |
451f92163
|
1099 1100 |
.flags = NL_CFG_F_NONROOT_RECV, .groups = AUDIT_NLGRP_MAX, |
a31f2d17b
|
1101 |
}; |
f368c07d7
|
1102 |
|
33faba7fa
|
1103 |
struct audit_net *aunet = net_generic(net, audit_net_id); |
33faba7fa
|
1104 |
aunet->nlsk = netlink_kernel_create(net, NETLINK_AUDIT, &cfg); |
11ee39ebf
|
1105 |
if (aunet->nlsk == NULL) { |
33faba7fa
|
1106 |
audit_panic("cannot initialize netlink socket in namespace"); |
11ee39ebf
|
1107 1108 1109 |
return -ENOMEM; } aunet->nlsk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; |
33faba7fa
|
1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 |
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
|
1121 |
RCU_INIT_POINTER(aunet->nlsk, NULL); |
33faba7fa
|
1122 1123 1124 |
synchronize_net(); netlink_kernel_release(sock); } |
8626877b5
|
1125 |
static struct pernet_operations audit_net_ops __net_initdata = { |
33faba7fa
|
1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 |
.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
|
1136 1137 |
if (audit_initialized == AUDIT_DISABLED) return 0; |
d957f7b72
|
1138 1139 1140 |
pr_info("initializing netlink subsys (%s) ", audit_default ? "enabled" : "disabled"); |
33faba7fa
|
1141 |
register_pernet_subsys(&audit_net_ops); |
1da177e4c
|
1142 |
|
b7d112581
|
1143 |
skb_queue_head_init(&audit_skb_queue); |
f3d357b09
|
1144 |
skb_queue_head_init(&audit_skb_hold_queue); |
a3f07114e
|
1145 |
audit_initialized = AUDIT_INITIALIZED; |
1da177e4c
|
1146 |
audit_enabled = audit_default; |
b593d384e
|
1147 |
audit_ever_enabled |= !!audit_default; |
3dc7e3153
|
1148 |
|
9ad9ad385
|
1149 |
audit_log(NULL, GFP_KERNEL, AUDIT_KERNEL, "initialized"); |
f368c07d7
|
1150 |
|
f368c07d7
|
1151 1152 |
for (i = 0; i < AUDIT_INODE_BUCKETS; i++) INIT_LIST_HEAD(&audit_inode_hash[i]); |
f368c07d7
|
1153 |
|
1da177e4c
|
1154 1155 |
return 0; } |
1da177e4c
|
1156 1157 1158 1159 1160 1161 |
__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
|
1162 1163 |
if (!audit_default) audit_initialized = AUDIT_DISABLED; |
d957f7b72
|
1164 1165 |
pr_info("%s ", audit_default ? |
d3ca0344b
|
1166 |
"enabled (after initialization)" : "disabled (until reboot)"); |
a3f07114e
|
1167 |
|
9b41046cd
|
1168 |
return 1; |
1da177e4c
|
1169 |
} |
1da177e4c
|
1170 |
__setup("audit=", audit_enable); |
f910fde73
|
1171 1172 1173 1174 |
/* Process kernel command-line parameter at boot time. * audit_backlog_limit=<n> */ static int __init audit_backlog_limit_set(char *str) { |
3e1d0bb62
|
1175 |
u32 audit_backlog_limit_arg; |
d957f7b72
|
1176 |
|
f910fde73
|
1177 |
pr_info("audit_backlog_limit: "); |
3e1d0bb62
|
1178 1179 1180 |
if (kstrtouint(str, 0, &audit_backlog_limit_arg)) { pr_cont("using default of %u, unable to parse %s ", |
d957f7b72
|
1181 |
audit_backlog_limit, str); |
f910fde73
|
1182 1183 |
return 1; } |
3e1d0bb62
|
1184 1185 |
audit_backlog_limit = audit_backlog_limit_arg; |
d957f7b72
|
1186 1187 |
pr_cont("%d ", audit_backlog_limit); |
f910fde73
|
1188 1189 1190 1191 |
return 1; } __setup("audit_backlog_limit=", audit_backlog_limit_set); |
16e1904e6
|
1192 1193 1194 |
static void audit_buffer_free(struct audit_buffer *ab) { unsigned long flags; |
8fc6115c2
|
1195 1196 |
if (!ab) return; |
d865e573b
|
1197 |
kfree_skb(ab->skb); |
16e1904e6
|
1198 |
spin_lock_irqsave(&audit_freelist_lock, flags); |
5d136a010
|
1199 |
if (audit_freelist_count > AUDIT_MAXFREE) |
16e1904e6
|
1200 |
kfree(ab); |
5d136a010
|
1201 1202 |
else { audit_freelist_count++; |
16e1904e6
|
1203 |
list_add(&ab->list, &audit_freelist); |
5d136a010
|
1204 |
} |
16e1904e6
|
1205 1206 |
spin_unlock_irqrestore(&audit_freelist_lock, flags); } |
c04049939
|
1207 |
static struct audit_buffer * audit_buffer_alloc(struct audit_context *ctx, |
dd0fc66fb
|
1208 |
gfp_t gfp_mask, int type) |
16e1904e6
|
1209 1210 1211 |
{ unsigned long flags; struct audit_buffer *ab = NULL; |
c04049939
|
1212 |
struct nlmsghdr *nlh; |
16e1904e6
|
1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 |
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
|
1224 |
ab = kmalloc(sizeof(*ab), gfp_mask); |
16e1904e6
|
1225 |
if (!ab) |
8fc6115c2
|
1226 |
goto err; |
16e1904e6
|
1227 |
} |
8fc6115c2
|
1228 |
|
b7d112581
|
1229 |
ab->ctx = ctx; |
9ad9ad385
|
1230 |
ab->gfp_mask = gfp_mask; |
ee080e6ce
|
1231 1232 1233 |
ab->skb = nlmsg_new(AUDIT_BUFSIZ, gfp_mask); if (!ab->skb) |
c64e66c67
|
1234 |
goto err; |
ee080e6ce
|
1235 |
|
c64e66c67
|
1236 1237 1238 |
nlh = nlmsg_put(ab->skb, 0, 0, type, 0, 0); if (!nlh) goto out_kfree_skb; |
ee080e6ce
|
1239 |
|
16e1904e6
|
1240 |
return ab; |
ee080e6ce
|
1241 |
|
c64e66c67
|
1242 |
out_kfree_skb: |
ee080e6ce
|
1243 1244 |
kfree_skb(ab->skb); ab->skb = NULL; |
8fc6115c2
|
1245 1246 1247 |
err: audit_buffer_free(ab); return NULL; |
16e1904e6
|
1248 |
} |
1da177e4c
|
1249 |
|
b0dd25a82
|
1250 1251 1252 1253 |
/** * audit_serial - compute a serial number for the audit record * * Compute a serial number for the audit record. Audit records are |
bfb4496e7
|
1254 1255 1256 1257 1258 1259 1260 |
* 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
|
1261 1262 1263 1264 |
* 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
|
1265 1266 |
* halts). */ |
bfb4496e7
|
1267 1268 |
unsigned int audit_serial(void) { |
01478d7d6
|
1269 |
static atomic_t serial = ATOMIC_INIT(0); |
d5b454f2c
|
1270 |
|
01478d7d6
|
1271 |
return atomic_add_return(1, &serial); |
bfb4496e7
|
1272 |
} |
5600b8927
|
1273 |
static inline void audit_get_stamp(struct audit_context *ctx, |
bfb4496e7
|
1274 1275 |
struct timespec *t, unsigned int *serial) { |
48887e63d
|
1276 |
if (!ctx || !auditsc_get_stamp(ctx, t, serial)) { |
bfb4496e7
|
1277 1278 1279 1280 |
*t = CURRENT_TIME; *serial = audit_serial(); } } |
829199197
|
1281 1282 1283 |
/* * Wait for auditd to drain the queue a little */ |
c81825dd6
|
1284 |
static long wait_for_auditd(long sleep_time) |
829199197
|
1285 1286 |
{ DECLARE_WAITQUEUE(wait, current); |
829199197
|
1287 1288 |
if (audit_backlog_limit && |
7ffb8e317
|
1289 1290 1291 |
skb_queue_len(&audit_skb_queue) > audit_backlog_limit) { add_wait_queue_exclusive(&audit_backlog_wait, &wait); set_current_state(TASK_UNINTERRUPTIBLE); |
c81825dd6
|
1292 |
sleep_time = schedule_timeout(sleep_time); |
7ffb8e317
|
1293 1294 |
remove_wait_queue(&audit_backlog_wait, &wait); } |
ae887e0bd
|
1295 |
|
c81825dd6
|
1296 |
return sleep_time; |
829199197
|
1297 |
} |
b0dd25a82
|
1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 |
/** * 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
|
1313 |
struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, |
9ad9ad385
|
1314 |
int type) |
1da177e4c
|
1315 1316 |
{ struct audit_buffer *ab = NULL; |
1da177e4c
|
1317 |
struct timespec t; |
ef00be055
|
1318 |
unsigned int uninitialized_var(serial); |
6dd80aba9
|
1319 1320 |
int reserve = 5; /* Allow atomic callers to go up to five entries over the normal backlog limit */ |
ac4cec443
|
1321 |
unsigned long timeout_start = jiffies; |
1da177e4c
|
1322 |
|
a3f07114e
|
1323 |
if (audit_initialized != AUDIT_INITIALIZED) |
1da177e4c
|
1324 |
return NULL; |
c8edc80c8
|
1325 1326 |
if (unlikely(audit_filter_type(type))) return NULL; |
d0164adc8
|
1327 |
if (gfp_mask & __GFP_DIRECT_RECLAIM) { |
f48a94292
|
1328 |
if (audit_pid && audit_pid == current->tgid) |
d0164adc8
|
1329 |
gfp_mask &= ~__GFP_DIRECT_RECLAIM; |
6dd80aba9
|
1330 1331 1332 |
else reserve = 0; } |
9ad9ad385
|
1333 1334 1335 |
while (audit_backlog_limit && skb_queue_len(&audit_skb_queue) > audit_backlog_limit + reserve) { |
d0164adc8
|
1336 |
if (gfp_mask & __GFP_DIRECT_RECLAIM && audit_backlog_wait_time) { |
c81825dd6
|
1337 |
long sleep_time; |
9ad9ad385
|
1338 |
|
c81825dd6
|
1339 1340 |
sleep_time = timeout_start + audit_backlog_wait_time - jiffies; if (sleep_time > 0) { |
ae887e0bd
|
1341 |
sleep_time = wait_for_auditd(sleep_time); |
c81825dd6
|
1342 |
if (sleep_time > 0) |
ae887e0bd
|
1343 |
continue; |
8ac1c8d5d
|
1344 |
} |
9ad9ad385
|
1345 |
} |
320f1b1ed
|
1346 |
if (audit_rate_check() && printk_ratelimit()) |
d957f7b72
|
1347 1348 1349 1350 |
pr_warn("audit_backlog=%d > audit_backlog_limit=%d ", skb_queue_len(&audit_skb_queue), audit_backlog_limit); |
fb19b4c6a
|
1351 |
audit_log_lost("backlog limit exceeded"); |
eb8baf6aa
|
1352 |
audit_backlog_wait_time = 0; |
ac4cec443
|
1353 |
wake_up(&audit_backlog_wait); |
fb19b4c6a
|
1354 1355 |
return NULL; } |
c4b7a7755
|
1356 |
if (!reserve && !audit_backlog_wait_time) |
efef73a1a
|
1357 |
audit_backlog_wait_time = audit_backlog_wait_time_master; |
e789e561a
|
1358 |
|
9ad9ad385
|
1359 |
ab = audit_buffer_alloc(ctx, gfp_mask, type); |
1da177e4c
|
1360 1361 1362 1363 |
if (!ab) { audit_log_lost("out of memory in audit_log_start"); return NULL; } |
bfb4496e7
|
1364 |
audit_get_stamp(ab->ctx, &t, &serial); |
197c69c6a
|
1365 |
|
1da177e4c
|
1366 1367 1368 1369 |
audit_log_format(ab, "audit(%lu.%03lu:%u): ", t.tv_sec, t.tv_nsec/1000000, serial); return ab; } |
8fc6115c2
|
1370 |
/** |
5ac52f33b
|
1371 |
* audit_expand - expand skb in the audit buffer |
8fc6115c2
|
1372 |
* @ab: audit_buffer |
b0dd25a82
|
1373 |
* @extra: space to add at tail of the skb |
8fc6115c2
|
1374 1375 1376 1377 |
* * Returns 0 (no space) on failed expansion, or available space if * successful. */ |
e3b926b4c
|
1378 |
static inline int audit_expand(struct audit_buffer *ab, int extra) |
8fc6115c2
|
1379 |
{ |
5ac52f33b
|
1380 |
struct sk_buff *skb = ab->skb; |
406a1d868
|
1381 1382 1383 |
int oldtail = skb_tailroom(skb); int ret = pskb_expand_head(skb, 0, extra, ab->gfp_mask); int newtail = skb_tailroom(skb); |
5ac52f33b
|
1384 1385 |
if (ret < 0) { audit_log_lost("out of memory in audit_expand"); |
8fc6115c2
|
1386 |
return 0; |
5ac52f33b
|
1387 |
} |
406a1d868
|
1388 1389 1390 |
skb->truesize += newtail - oldtail; return newtail; |
8fc6115c2
|
1391 |
} |
1da177e4c
|
1392 |
|
b0dd25a82
|
1393 1394 |
/* * Format an audit message into the audit buffer. If there isn't enough |
1da177e4c
|
1395 1396 |
* 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
|
1397 1398 |
* can't format message larger than 1024 bytes, so we don't either. */ |
1da177e4c
|
1399 1400 1401 1402 |
static void audit_log_vformat(struct audit_buffer *ab, const char *fmt, va_list args) { int len, avail; |
5ac52f33b
|
1403 |
struct sk_buff *skb; |
eecb0a733
|
1404 |
va_list args2; |
1da177e4c
|
1405 1406 1407 |
if (!ab) return; |
5ac52f33b
|
1408 1409 1410 1411 |
BUG_ON(!ab->skb); skb = ab->skb; avail = skb_tailroom(skb); if (avail == 0) { |
e3b926b4c
|
1412 |
avail = audit_expand(ab, AUDIT_BUFSIZ); |
8fc6115c2
|
1413 1414 |
if (!avail) goto out; |
1da177e4c
|
1415 |
} |
eecb0a733
|
1416 |
va_copy(args2, args); |
27a884dc3
|
1417 |
len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args); |
1da177e4c
|
1418 1419 1420 1421 |
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
|
1422 1423 |
avail = audit_expand(ab, max_t(unsigned, AUDIT_BUFSIZ, 1+len-avail)); |
8fc6115c2
|
1424 |
if (!avail) |
a0e86bd42
|
1425 |
goto out_va_end; |
27a884dc3
|
1426 |
len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args2); |
1da177e4c
|
1427 |
} |
168b71739
|
1428 1429 |
if (len > 0) skb_put(skb, len); |
a0e86bd42
|
1430 1431 |
out_va_end: va_end(args2); |
8fc6115c2
|
1432 1433 |
out: return; |
1da177e4c
|
1434 |
} |
b0dd25a82
|
1435 1436 1437 1438 1439 1440 1441 1442 |
/** * 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
|
1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 |
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
|
1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 |
/** * 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
|
1464 |
void audit_log_n_hex(struct audit_buffer *ab, const unsigned char *buf, |
168b71739
|
1465 |
size_t len) |
83c7d0917
|
1466 |
{ |
168b71739
|
1467 1468 1469 |
int i, avail, new_len; unsigned char *ptr; struct sk_buff *skb; |
168b71739
|
1470 |
|
8ef2d3040
|
1471 1472 |
if (!ab) return; |
168b71739
|
1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 |
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
|
1484 |
|
27a884dc3
|
1485 |
ptr = skb_tail_pointer(skb); |
b8dbc3241
|
1486 1487 |
for (i = 0; i < len; i++) ptr = hex_byte_pack_upper(ptr, buf[i]); |
168b71739
|
1488 1489 |
*ptr = 0; skb_put(skb, len << 1); /* new string is twice the old string */ |
83c7d0917
|
1490 |
} |
9c937dcc7
|
1491 1492 1493 1494 |
/* * Format a string of no more than slen characters into the audit buffer, * enclosed in quote marks. */ |
b556f8ad5
|
1495 1496 |
void audit_log_n_string(struct audit_buffer *ab, const char *string, size_t slen) |
9c937dcc7
|
1497 1498 1499 1500 |
{ int avail, new_len; unsigned char *ptr; struct sk_buff *skb; |
8ef2d3040
|
1501 1502 |
if (!ab) return; |
9c937dcc7
|
1503 1504 1505 1506 1507 1508 1509 1510 1511 |
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
|
1512 |
ptr = skb_tail_pointer(skb); |
9c937dcc7
|
1513 1514 1515 1516 1517 1518 1519 |
*ptr++ = '"'; memcpy(ptr, string, slen); ptr += slen; *ptr++ = '"'; *ptr = 0; skb_put(skb, slen + 2); /* don't include null terminator */ } |
b0dd25a82
|
1520 |
/** |
de6bbd1d3
|
1521 |
* audit_string_contains_control - does a string need to be logged in hex |
f706d5d22
|
1522 1523 |
* @string: string to be checked * @len: max length of the string to check |
de6bbd1d3
|
1524 |
*/ |
9fcf836b2
|
1525 |
bool audit_string_contains_control(const char *string, size_t len) |
de6bbd1d3
|
1526 1527 |
{ const unsigned char *p; |
b3897f567
|
1528 |
for (p = string; p < (const unsigned char *)string + len; p++) { |
1d6c9649e
|
1529 |
if (*p == '"' || *p < 0x21 || *p > 0x7e) |
9fcf836b2
|
1530 |
return true; |
de6bbd1d3
|
1531 |
} |
9fcf836b2
|
1532 |
return false; |
de6bbd1d3
|
1533 1534 1535 |
} /** |
522ed7767
|
1536 |
* audit_log_n_untrustedstring - log a string that may contain random characters |
b0dd25a82
|
1537 |
* @ab: audit_buffer |
f706d5d22
|
1538 |
* @len: length of string (not including trailing null) |
b0dd25a82
|
1539 1540 1541 1542 |
* @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
|
1543 |
* or a space. Unescaped strings will start and end with a double quote mark. |
b0dd25a82
|
1544 |
* Strings that are escaped are printed in hex (2 digits per char). |
9c937dcc7
|
1545 1546 1547 |
* * The caller specifies the number of characters in the string to log, which may * or may not be the entire string. |
b0dd25a82
|
1548 |
*/ |
b556f8ad5
|
1549 1550 |
void audit_log_n_untrustedstring(struct audit_buffer *ab, const char *string, size_t len) |
83c7d0917
|
1551 |
{ |
de6bbd1d3
|
1552 |
if (audit_string_contains_control(string, len)) |
b556f8ad5
|
1553 |
audit_log_n_hex(ab, string, len); |
de6bbd1d3
|
1554 |
else |
b556f8ad5
|
1555 |
audit_log_n_string(ab, string, len); |
83c7d0917
|
1556 |
} |
9c937dcc7
|
1557 |
/** |
522ed7767
|
1558 |
* audit_log_untrustedstring - log a string that may contain random characters |
9c937dcc7
|
1559 1560 1561 |
* @ab: audit_buffer * @string: string to be logged * |
522ed7767
|
1562 |
* Same as audit_log_n_untrustedstring(), except that strlen is used to |
9c937dcc7
|
1563 1564 |
* determine string length. */ |
de6bbd1d3
|
1565 |
void audit_log_untrustedstring(struct audit_buffer *ab, const char *string) |
9c937dcc7
|
1566 |
{ |
b556f8ad5
|
1567 |
audit_log_n_untrustedstring(ab, string, strlen(string)); |
9c937dcc7
|
1568 |
} |
168b71739
|
1569 |
/* This is a helper-function to print the escaped d_path */ |
1da177e4c
|
1570 |
void audit_log_d_path(struct audit_buffer *ab, const char *prefix, |
66b3fad3f
|
1571 |
const struct path *path) |
1da177e4c
|
1572 |
{ |
44707fdf5
|
1573 |
char *p, *pathname; |
1da177e4c
|
1574 |
|
8fc6115c2
|
1575 |
if (prefix) |
c158a35c8
|
1576 |
audit_log_format(ab, "%s", prefix); |
1da177e4c
|
1577 |
|
168b71739
|
1578 |
/* We will allow 11 spaces for ' (deleted)' to be appended */ |
44707fdf5
|
1579 1580 |
pathname = kmalloc(PATH_MAX+11, ab->gfp_mask); if (!pathname) { |
def575434
|
1581 |
audit_log_string(ab, "<no_memory>"); |
168b71739
|
1582 |
return; |
1da177e4c
|
1583 |
} |
cf28b4863
|
1584 |
p = d_path(path, pathname, PATH_MAX+11); |
168b71739
|
1585 1586 |
if (IS_ERR(p)) { /* Should never happen since we send PATH_MAX */ /* FIXME: can we save some information here? */ |
def575434
|
1587 |
audit_log_string(ab, "<too_long>"); |
5600b8927
|
1588 |
} else |
168b71739
|
1589 |
audit_log_untrustedstring(ab, p); |
44707fdf5
|
1590 |
kfree(pathname); |
1da177e4c
|
1591 |
} |
4d3fb709b
|
1592 1593 |
void audit_log_session_info(struct audit_buffer *ab) { |
4440e8548
|
1594 |
unsigned int sessionid = audit_get_sessionid(current); |
4d3fb709b
|
1595 |
uid_t auid = from_kuid(&init_user_ns, audit_get_loginuid(current)); |
b8f89caaf
|
1596 |
audit_log_format(ab, " auid=%u ses=%u", auid, sessionid); |
4d3fb709b
|
1597 |
} |
9d9609851
|
1598 1599 1600 1601 1602 1603 1604 1605 |
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
|
1606 1607 1608 1609 1610 1611 1612 |
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
|
1613 |
cap->cap[CAP_LAST_U32 - i]); |
b24a30a73
|
1614 1615 |
} } |
691e6d59d
|
1616 |
static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name) |
b24a30a73
|
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 |
{ 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, |
d6335d77a
|
1660 |
struct inode *inode) |
b24a30a73
|
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 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 |
{ 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
|
1712 |
if (n->ino != AUDIT_INO_UNSET) |
b24a30a73
|
1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 |
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
|
1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 |
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
|
1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 |
/* 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
|
1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 |
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
|
1787 1788 1789 |
void audit_log_d_path_exe(struct audit_buffer *ab, struct mm_struct *mm) { |
5b2825527
|
1790 1791 1792 1793 |
struct file *exe_file; if (!mm) goto out_null; |
4766b199e
|
1794 |
|
5b2825527
|
1795 1796 1797 1798 1799 1800 1801 1802 1803 |
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
|
1804 |
} |
b24a30a73
|
1805 1806 1807 |
void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk) { const struct cred *cred; |
9eab339b1
|
1808 |
char comm[sizeof(tsk->comm)]; |
db0a6fb5d
|
1809 |
struct tty_struct *tty; |
b24a30a73
|
1810 1811 1812 1813 1814 1815 |
if (!ab) return; /* tsk == current */ cred = current_cred(); |
db0a6fb5d
|
1816 |
tty = audit_get_tty(tsk); |
b24a30a73
|
1817 |
audit_log_format(ab, |
c92cdeb45
|
1818 |
" ppid=%d pid=%d auid=%u uid=%u gid=%u" |
b24a30a73
|
1819 |
" euid=%u suid=%u fsuid=%u" |
2f2ad1013
|
1820 |
" egid=%u sgid=%u fsgid=%u tty=%s ses=%u", |
c92cdeb45
|
1821 |
task_ppid_nr(tsk), |
f1dc4867f
|
1822 |
task_pid_nr(tsk), |
b24a30a73
|
1823 1824 1825 1826 1827 1828 1829 1830 1831 |
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), |
db0a6fb5d
|
1832 1833 1834 |
tty ? tty_name(tty) : "(none)", audit_get_sessionid(tsk)); audit_put_tty(tty); |
b24a30a73
|
1835 |
audit_log_format(ab, " comm="); |
9eab339b1
|
1836 |
audit_log_untrustedstring(ab, get_task_comm(comm, tsk)); |
4766b199e
|
1837 |
audit_log_d_path_exe(ab, tsk->mm); |
b24a30a73
|
1838 1839 1840 |
audit_log_task_context(ab); } EXPORT_SYMBOL(audit_log_task_info); |
b0dd25a82
|
1841 |
/** |
a51d9eaa4
|
1842 |
* audit_log_link_denied - report a link restriction denial |
220119647
|
1843 |
* @operation: specific link operation |
a51d9eaa4
|
1844 1845 1846 1847 1848 |
* @link: the path that triggered the restriction */ void audit_log_link_denied(const char *operation, struct path *link) { struct audit_buffer *ab; |
b24a30a73
|
1849 1850 1851 1852 1853 |
struct audit_names *name; name = kzalloc(sizeof(*name), GFP_NOFS); if (!name) return; |
a51d9eaa4
|
1854 |
|
b24a30a73
|
1855 |
/* Generate AUDIT_ANOM_LINK with subject, operation, outcome. */ |
a51d9eaa4
|
1856 1857 |
ab = audit_log_start(current->audit_context, GFP_KERNEL, AUDIT_ANOM_LINK); |
d1c7d97ad
|
1858 |
if (!ab) |
b24a30a73
|
1859 1860 1861 1862 |
goto out; audit_log_format(ab, "op=%s", operation); audit_log_task_info(ab, current); audit_log_format(ab, " res=0"); |
a51d9eaa4
|
1863 |
audit_log_end(ab); |
b24a30a73
|
1864 1865 1866 |
/* Generate AUDIT_PATH record with object. */ name->type = AUDIT_TYPE_NORMAL; |
3b362157b
|
1867 |
audit_copy_inode(name, link->dentry, d_backing_inode(link->dentry)); |
b24a30a73
|
1868 1869 1870 |
audit_log_name(current->audit_context, name, link, 0, NULL); out: kfree(name); |
a51d9eaa4
|
1871 1872 1873 |
} /** |
b0dd25a82
|
1874 1875 1876 |
* audit_log_end - end one audit record * @ab: the audit_buffer * |
451f92163
|
1877 1878 1879 1880 |
* 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
|
1881 |
*/ |
b7d112581
|
1882 |
void audit_log_end(struct audit_buffer *ab) |
1da177e4c
|
1883 |
{ |
1da177e4c
|
1884 1885 1886 1887 1888 |
if (!ab) return; if (!audit_rate_check()) { audit_log_lost("rate limit exceeded"); } else { |
8d07a67cf
|
1889 |
struct nlmsghdr *nlh = nlmsg_hdr(ab->skb); |
451f92163
|
1890 |
|
54e05eddb
|
1891 |
nlh->nlmsg_len = ab->skb->len; |
54dc77d97
|
1892 |
kauditd_send_multicast_skb(ab->skb, ab->gfp_mask); |
451f92163
|
1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 |
/* * 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
|
1903 |
nlh->nlmsg_len -= NLMSG_HDRLEN; |
f3d357b09
|
1904 |
|
b7d112581
|
1905 |
if (audit_pid) { |
b7d112581
|
1906 |
skb_queue_tail(&audit_skb_queue, ab->skb); |
b7d112581
|
1907 |
wake_up_interruptible(&kauditd_wait); |
f3d357b09
|
1908 |
} else { |
038cbcf65
|
1909 |
audit_printk_skb(ab->skb); |
b7d112581
|
1910 |
} |
f3d357b09
|
1911 |
ab->skb = NULL; |
1da177e4c
|
1912 |
} |
16e1904e6
|
1913 |
audit_buffer_free(ab); |
1da177e4c
|
1914 |
} |
b0dd25a82
|
1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 |
/** * 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
|
1927 |
void audit_log(struct audit_context *ctx, gfp_t gfp_mask, int type, |
9ad9ad385
|
1928 |
const char *fmt, ...) |
1da177e4c
|
1929 1930 1931 |
{ struct audit_buffer *ab; va_list args; |
9ad9ad385
|
1932 |
ab = audit_log_start(ctx, gfp_mask, type); |
1da177e4c
|
1933 1934 1935 1936 1937 1938 1939 |
if (ab) { va_start(args, fmt); audit_log_vformat(ab, fmt, args); va_end(args); audit_log_end(ab); } } |
bf45da97a
|
1940 |
|
131ad62d8
|
1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 |
#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
|
1966 1967 1968 1969 |
EXPORT_SYMBOL(audit_log_start); EXPORT_SYMBOL(audit_log_end); EXPORT_SYMBOL(audit_log_format); EXPORT_SYMBOL(audit_log); |