diff options
Diffstat (limited to 'kernel/audit.c')
-rw-r--r-- | kernel/audit.c | 112 |
1 files changed, 68 insertions, 44 deletions
diff --git a/kernel/audit.c b/kernel/audit.c index 0f84dd7af2c..9c4f1af0c79 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -1,4 +1,4 @@ -/* audit.c -- Auditing support -*- linux-c -*- +/* audit.c -- Auditing support * Gateway between the kernel (e.g., selinux) and the user-space audit daemon. * System-call specific features have moved to auditsc.c * @@ -38,7 +38,7 @@ * 6) Support low-overhead kernel-based filtering to minimize the * information that must be passed to user-space. * - * Example user-space utilities: http://people.redhat.com/faith/audit/ + * Example user-space utilities: http://people.redhat.com/sgrubb/audit/ */ #include <linux/init.h> @@ -142,7 +142,6 @@ struct audit_buffer { int total; int type; int pid; - int count; /* Times requeued */ }; void audit_set_type(struct audit_buffer *ab, int type) @@ -239,36 +238,36 @@ void audit_log_lost(const char *message) } -static int audit_set_rate_limit(int limit) +static int audit_set_rate_limit(int limit, uid_t loginuid) { int old = audit_rate_limit; audit_rate_limit = limit; - audit_log(current->audit_context, "audit_rate_limit=%d old=%d", - audit_rate_limit, old); + audit_log(NULL, "audit_rate_limit=%d old=%d by auid %u", + audit_rate_limit, old, loginuid); return old; } -static int audit_set_backlog_limit(int limit) +static int audit_set_backlog_limit(int limit, uid_t loginuid) { int old = audit_backlog_limit; audit_backlog_limit = limit; - audit_log(current->audit_context, "audit_backlog_limit=%d old=%d", - audit_backlog_limit, old); + audit_log(NULL, "audit_backlog_limit=%d old=%d by auid %u", + audit_backlog_limit, old, loginuid); return old; } -static int audit_set_enabled(int state) +static int audit_set_enabled(int state, uid_t loginuid) { int old = audit_enabled; if (state != 0 && state != 1) return -EINVAL; audit_enabled = state; - audit_log(current->audit_context, "audit_enabled=%d old=%d", - audit_enabled, old); + audit_log(NULL, "audit_enabled=%d old=%d by auid %u", + audit_enabled, old, loginuid); return old; } -static int audit_set_failure(int state) +static int audit_set_failure(int state, uid_t loginuid) { int old = audit_failure; if (state != AUDIT_FAIL_SILENT @@ -276,8 +275,8 @@ static int audit_set_failure(int state) && state != AUDIT_FAIL_PANIC) return -EINVAL; audit_failure = state; - audit_log(current->audit_context, "audit_failure=%d old=%d", - audit_failure, old); + audit_log(NULL, "audit_failure=%d old=%d by auid %u", + audit_failure, old, loginuid); return old; } @@ -344,6 +343,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) int err; struct audit_buffer *ab; u16 msg_type = nlh->nlmsg_type; + uid_t loginuid; /* loginuid of sender */ err = audit_netlink_ok(NETLINK_CB(skb).eff_cap, msg_type); if (err) @@ -351,6 +351,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) pid = NETLINK_CREDS(skb)->pid; uid = NETLINK_CREDS(skb)->uid; + loginuid = NETLINK_CB(skb).loginuid; seq = nlh->nlmsg_seq; data = NLMSG_DATA(nlh); @@ -371,34 +372,36 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) return -EINVAL; status_get = (struct audit_status *)data; if (status_get->mask & AUDIT_STATUS_ENABLED) { - err = audit_set_enabled(status_get->enabled); + err = audit_set_enabled(status_get->enabled, loginuid); if (err < 0) return err; } if (status_get->mask & AUDIT_STATUS_FAILURE) { - err = audit_set_failure(status_get->failure); + err = audit_set_failure(status_get->failure, loginuid); if (err < 0) return err; } if (status_get->mask & AUDIT_STATUS_PID) { int old = audit_pid; audit_pid = status_get->pid; - audit_log(current->audit_context, - "audit_pid=%d old=%d", audit_pid, old); + audit_log(NULL, "audit_pid=%d old=%d by auid %u", + audit_pid, old, loginuid); } if (status_get->mask & AUDIT_STATUS_RATE_LIMIT) - audit_set_rate_limit(status_get->rate_limit); + audit_set_rate_limit(status_get->rate_limit, loginuid); if (status_get->mask & AUDIT_STATUS_BACKLOG_LIMIT) - audit_set_backlog_limit(status_get->backlog_limit); + audit_set_backlog_limit(status_get->backlog_limit, + loginuid); break; case AUDIT_USER: ab = audit_log_start(NULL); if (!ab) break; /* audit_panic has been called */ audit_log_format(ab, - "user pid=%d uid=%d length=%d msg='%.1024s'", + "user pid=%d uid=%d length=%d loginuid=%u" + " msg='%.1024s'", pid, uid, (int)(nlh->nlmsg_len - ((char *)data - (char *)nlh)), - (char *)data); + loginuid, (char *)data); ab->type = AUDIT_USER; ab->pid = pid; audit_log_end(ab); @@ -411,7 +414,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) case AUDIT_LIST: #ifdef CONFIG_AUDITSYSCALL err = audit_receive_filter(nlh->nlmsg_type, NETLINK_CB(skb).pid, - uid, seq, data); + uid, seq, data, loginuid); #else err = -EOPNOTSUPP; #endif @@ -427,7 +430,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) /* Get message from skb (based on rtnetlink_rcv_skb). Each message is * processed by audit_receive_msg. Malformed skbs with wrong length are * discarded silently. */ -static int audit_receive_skb(struct sk_buff *skb) +static void audit_receive_skb(struct sk_buff *skb) { int err; struct nlmsghdr *nlh; @@ -436,7 +439,7 @@ static int audit_receive_skb(struct sk_buff *skb) while (skb->len >= NLMSG_SPACE(0)) { nlh = (struct nlmsghdr *)skb->data; if (nlh->nlmsg_len < sizeof(*nlh) || skb->len < nlh->nlmsg_len) - return 0; + return; rlen = NLMSG_ALIGN(nlh->nlmsg_len); if (rlen > skb->len) rlen = skb->len; @@ -446,23 +449,20 @@ static int audit_receive_skb(struct sk_buff *skb) netlink_ack(skb, nlh, 0); skb_pull(skb, rlen); } - return 0; } /* Receive messages from netlink socket. */ static void audit_receive(struct sock *sk, int length) { struct sk_buff *skb; + unsigned int qlen; - if (down_trylock(&audit_netlink_sem)) - return; + down(&audit_netlink_sem); - /* FIXME: this must not cause starvation */ - while ((skb = skb_dequeue(&sk->sk_receive_queue))) { - if (audit_receive_skb(skb) && skb->len) - skb_queue_head(&sk->sk_receive_queue, skb); - else - kfree_skb(skb); + for (qlen = skb_queue_len(&sk->sk_receive_queue); qlen; qlen--) { + skb = skb_dequeue(&sk->sk_receive_queue); + audit_receive_skb(skb); + kfree_skb(skb); } up(&audit_netlink_sem); } @@ -483,7 +483,7 @@ static void audit_log_move(struct audit_buffer *ab) if (ab->len == 0) return; - skb = skb_peek(&ab->sklist); + skb = skb_peek_tail(&ab->sklist); if (!skb || skb_tailroom(skb) <= ab->len + extra) { skb = alloc_skb(2 * ab->len + extra, GFP_ATOMIC); if (!skb) { @@ -522,9 +522,9 @@ static inline int audit_log_drain(struct audit_buffer *ab) retval = netlink_unicast(audit_sock, skb, audit_pid, MSG_DONTWAIT); } - if (retval == -EAGAIN && ab->count < 5) { - ++ab->count; - skb_queue_tail(&ab->sklist, skb); + if (retval == -EAGAIN && + (atomic_read(&audit_backlog)) < audit_backlog_limit) { + skb_queue_head(&ab->sklist, skb); audit_log_end_irq(ab); return 1; } @@ -540,8 +540,8 @@ static inline int audit_log_drain(struct audit_buffer *ab) if (!audit_pid) { /* No daemon */ int offset = ab->nlh ? NLMSG_SPACE(0) : 0; int len = skb->len - offset; - printk(KERN_ERR "%*.*s\n", - len, len, skb->data + offset); + skb->data[offset + len] = '\0'; + printk(KERN_ERR "%s\n", skb->data + offset); } kfree_skb(skb); ab->nlh = NULL; @@ -620,7 +620,7 @@ struct audit_buffer *audit_log_start(struct audit_context *ctx) struct audit_buffer *ab = NULL; unsigned long flags; struct timespec t; - int serial = 0; + unsigned int serial; if (!audit_initialized) return NULL; @@ -662,15 +662,16 @@ struct audit_buffer *audit_log_start(struct audit_context *ctx) ab->total = 0; ab->type = AUDIT_KERNEL; ab->pid = 0; - ab->count = 0; #ifdef CONFIG_AUDITSYSCALL if (ab->ctx) audit_get_stamp(ab->ctx, &t, &serial); else #endif + { t = CURRENT_TIME; - + serial = 0; + } audit_log_format(ab, "audit(%lu.%03lu:%u): ", t.tv_sec, t.tv_nsec/1000000, serial); return ab; @@ -720,6 +721,29 @@ void audit_log_format(struct audit_buffer *ab, const char *fmt, ...) va_end(args); } +void audit_log_hex(struct audit_buffer *ab, const unsigned char *buf, size_t len) +{ + int i; + + for (i=0; i<len; i++) + audit_log_format(ab, "%02x", buf[i]); +} + +void audit_log_untrustedstring(struct audit_buffer *ab, const char *string) +{ + const unsigned char *p = string; + + while (*p) { + if (*p == '"' || *p == ' ' || *p < 0x20 || *p > 0x7f) { + audit_log_hex(ab, string, strlen(string)); + return; + } + p++; + } + audit_log_format(ab, "\"%s\"", string); +} + + /* This is a helper-function to print the d_path without using a static * buffer or allocating another buffer in addition to the one in * audit_buffer. */ |