From eadd99cc85347b4f9eb10122ac90032eb4971b02 Mon Sep 17 00:00:00 2001 From: Tetsuo Handa Date: Sun, 26 Jun 2011 23:18:58 +0900 Subject: TOMOYO: Add auditing interface. Add /sys/kernel/security/tomoyo/audit interface. This interface generates audit logs in the form of domain policy so that /usr/sbin/tomoyo-auditd can reuse audit logs for appending to /sys/kernel/security/tomoyo/domain_policy interface. Signed-off-by: Tetsuo Handa Signed-off-by: James Morris --- security/tomoyo/common.c | 311 +++++++++++++++++++++++------------------------ 1 file changed, 151 insertions(+), 160 deletions(-) (limited to 'security/tomoyo/common.c') diff --git a/security/tomoyo/common.c b/security/tomoyo/common.c index 2b280350708f..6580ef35074b 100644 --- a/security/tomoyo/common.c +++ b/security/tomoyo/common.c @@ -17,9 +17,12 @@ static unsigned int tomoyo_profile_version; /* Profile table. Memory is allocated as needed. */ static struct tomoyo_profile *tomoyo_profile_ptr[TOMOYO_MAX_PROFILES]; -/* String table for functionality that takes 4 modes. */ -static const char *tomoyo_mode[4] = { - "disabled", "learning", "permissive", "enforcing" +/* String table for operation mode. */ +const char * const tomoyo_mode[TOMOYO_CONFIG_MAX_MODE] = { + [TOMOYO_CONFIG_DISABLED] = "disabled", + [TOMOYO_CONFIG_LEARNING] = "learning", + [TOMOYO_CONFIG_PERMISSIVE] = "permissive", + [TOMOYO_CONFIG_ENFORCING] = "enforcing" }; /* String table for /sys/kernel/security/tomoyo/profile */ @@ -53,6 +56,7 @@ static const char *tomoyo_mac_keywords[TOMOYO_MAX_MAC_INDEX /* String table for PREFERENCE keyword. */ static const char * const tomoyo_pref_keywords[TOMOYO_MAX_PREF] = { + [TOMOYO_PREF_MAX_AUDIT_LOG] = "max_audit_log", [TOMOYO_PREF_MAX_LEARNING_ENTRY] = "max_learning_entry", }; @@ -66,12 +70,10 @@ static bool tomoyo_manage_by_non_root; * * @value: Bool value. */ -/* -static const char *tomoyo_yesno(const unsigned int value) +const char *tomoyo_yesno(const unsigned int value) { return value ? "yes" : "no"; } -*/ /** * tomoyo_addprintf - strncat()-like-snprintf(). @@ -117,7 +119,7 @@ static bool tomoyo_flush(struct tomoyo_io_buffer *head) head->r.w[0] = w; if (*w) return false; - /* Add '\0' for query. */ + /* Add '\0' for audit logs and query. */ if (head->poll) { if (!head->read_user_buf_avail || copy_to_user(head->read_user_buf, "", 1)) @@ -300,9 +302,12 @@ static struct tomoyo_profile *tomoyo_assign_profile(const unsigned int profile) ptr = tomoyo_profile_ptr[profile]; if (!ptr && tomoyo_memory_ok(entry)) { ptr = entry; - ptr->default_config = TOMOYO_CONFIG_DISABLED; + ptr->default_config = TOMOYO_CONFIG_DISABLED | + TOMOYO_CONFIG_WANT_GRANT_LOG | + TOMOYO_CONFIG_WANT_REJECT_LOG; memset(ptr->config, TOMOYO_CONFIG_USE_DEFAULT, sizeof(ptr->config)); + ptr->pref[TOMOYO_PREF_MAX_AUDIT_LOG] = 1024; ptr->pref[TOMOYO_PREF_MAX_LEARNING_ENTRY] = 2048; mb(); /* Avoid out-of-order execution. */ tomoyo_profile_ptr[profile] = ptr; @@ -338,7 +343,6 @@ struct tomoyo_profile *tomoyo_profile(const u8 profile) * * Returns 1 if "@find=yes" was found, 0 if "@find=no" was found, -1 otherwise. */ -/* static s8 tomoyo_find_yesno(const char *string, const char *find) { const char *cp = strstr(string, find); @@ -351,7 +355,6 @@ static s8 tomoyo_find_yesno(const char *string, const char *find) } return -1; } -*/ /** * tomoyo_set_uint - Set value for specified preference. @@ -412,6 +415,24 @@ static int tomoyo_set_mode(char *name, const char *value, * 'config' from 'TOMOYO_CONFIG_USE_DEAFULT'. */ config = (config & ~7) | mode; + if (config != TOMOYO_CONFIG_USE_DEFAULT) { + switch (tomoyo_find_yesno(value, "grant_log")) { + case 1: + config |= TOMOYO_CONFIG_WANT_GRANT_LOG; + break; + case 0: + config &= ~TOMOYO_CONFIG_WANT_GRANT_LOG; + break; + } + switch (tomoyo_find_yesno(value, "reject_log")) { + case 1: + config |= TOMOYO_CONFIG_WANT_REJECT_LOG; + break; + case 0: + config &= ~TOMOYO_CONFIG_WANT_REJECT_LOG; + break; + } + } } if (i < TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX) profile->config[i] = config; @@ -469,15 +490,30 @@ static int tomoyo_write_profile(struct tomoyo_io_buffer *head) return tomoyo_set_mode(data, cp, profile); } +/** + * tomoyo_print_config - Print mode for specified functionality. + * + * @head: Pointer to "struct tomoyo_io_buffer". + * @config: Mode for that functionality. + * + * Returns nothing. + * + * Caller prints functionality's name. + */ static void tomoyo_print_config(struct tomoyo_io_buffer *head, const u8 config) { - tomoyo_io_printf(head, "={ mode=%s }\n", tomoyo_mode[config & 3]); + tomoyo_io_printf(head, "={ mode=%s grant_log=%s reject_log=%s }\n", + tomoyo_mode[config & 3], + tomoyo_yesno(config & TOMOYO_CONFIG_WANT_GRANT_LOG), + tomoyo_yesno(config & TOMOYO_CONFIG_WANT_REJECT_LOG)); } /** * tomoyo_read_profile - Read profile table. * * @head: Pointer to "struct tomoyo_io_buffer". + * + * Returns nothing. */ static void tomoyo_read_profile(struct tomoyo_io_buffer *head) { @@ -488,7 +524,7 @@ static void tomoyo_read_profile(struct tomoyo_io_buffer *head) profile = tomoyo_profile_ptr[index]; switch (head->r.step) { case 0: - tomoyo_io_printf(head, "PROFILE_VERSION=%s\n", "20090903"); + tomoyo_io_printf(head, "PROFILE_VERSION=%u\n", 20090903); head->r.step++; break; case 1: @@ -1359,103 +1395,68 @@ static void tomoyo_read_exception(struct tomoyo_io_buffer *head) head->r.eof = true; } -/** - * tomoyo_print_header - Get header line of audit log. - * - * @r: Pointer to "struct tomoyo_request_info". - * - * Returns string representation. - * - * This function uses kmalloc(), so caller must kfree() if this function - * didn't return NULL. - */ -static char *tomoyo_print_header(struct tomoyo_request_info *r) -{ - struct timeval tv; - const pid_t gpid = task_pid_nr(current); - static const int tomoyo_buffer_len = 4096; - char *buffer = kmalloc(tomoyo_buffer_len, GFP_NOFS); - pid_t ppid; - if (!buffer) - return NULL; - do_gettimeofday(&tv); - rcu_read_lock(); - ppid = task_tgid_vnr(current->real_parent); - rcu_read_unlock(); - snprintf(buffer, tomoyo_buffer_len - 1, - "#timestamp=%lu profile=%u mode=%s (global-pid=%u)" - " task={ pid=%u ppid=%u uid=%u gid=%u euid=%u" - " egid=%u suid=%u sgid=%u fsuid=%u fsgid=%u }", - tv.tv_sec, r->profile, tomoyo_mode[r->mode], gpid, - task_tgid_vnr(current), ppid, - current_uid(), current_gid(), current_euid(), - current_egid(), current_suid(), current_sgid(), - current_fsuid(), current_fsgid()); - return buffer; -} - -/** - * tomoyo_init_audit_log - Allocate buffer for audit logs. - * - * @len: Required size. - * @r: Pointer to "struct tomoyo_request_info". - * - * Returns pointer to allocated memory. - * - * The @len is updated to add the header lines' size on success. - * - * This function uses kzalloc(), so caller must kfree() if this function - * didn't return NULL. - */ -static char *tomoyo_init_audit_log(int *len, struct tomoyo_request_info *r) -{ - char *buf = NULL; - const char *header; - const char *domainname; - if (!r->domain) - r->domain = tomoyo_domain(); - domainname = r->domain->domainname->name; - header = tomoyo_print_header(r); - if (!header) - return NULL; - *len += strlen(domainname) + strlen(header) + 10; - buf = kzalloc(*len, GFP_NOFS); - if (buf) - snprintf(buf, (*len) - 1, "%s\n%s\n", header, domainname); - kfree(header); - return buf; -} - -/* Wait queue for tomoyo_query_list. */ +/* Wait queue for kernel -> userspace notification. */ static DECLARE_WAIT_QUEUE_HEAD(tomoyo_query_wait); - -/* Lock for manipulating tomoyo_query_list. */ -static DEFINE_SPINLOCK(tomoyo_query_list_lock); +/* Wait queue for userspace -> kernel notification. */ +static DECLARE_WAIT_QUEUE_HEAD(tomoyo_answer_wait); /* Structure for query. */ struct tomoyo_query { struct list_head list; char *query; - int query_len; + size_t query_len; unsigned int serial; - int timer; - int answer; + u8 timer; + u8 answer; + u8 retry; }; /* The list for "struct tomoyo_query". */ static LIST_HEAD(tomoyo_query_list); +/* Lock for manipulating tomoyo_query_list. */ +static DEFINE_SPINLOCK(tomoyo_query_list_lock); + /* * Number of "struct file" referring /sys/kernel/security/tomoyo/query * interface. */ static atomic_t tomoyo_query_observers = ATOMIC_INIT(0); +/** + * tomoyo_add_entry - Add an ACL to current thread's domain. Used by learning mode. + * + * @domain: Pointer to "struct tomoyo_domain_info". + * @header: Lines containing ACL. + * + * Returns nothing. + */ +static void tomoyo_add_entry(struct tomoyo_domain_info *domain, char *header) +{ + char *buffer; + char *cp = strchr(header, '\n'); + int len; + if (!cp) + return; + cp = strchr(cp + 1, '\n'); + if (!cp) + return; + *cp++ = '\0'; + len = strlen(cp) + 1; + buffer = kmalloc(len, GFP_NOFS); + if (!buffer) + return; + snprintf(buffer, len - 1, "%s", cp); + tomoyo_normalize_line(buffer); + tomoyo_write_domain2(&domain->acl_info_list, buffer, false); + kfree(buffer); +} + /** * tomoyo_supervisor - Ask for the supervisor's decision. * - * @r: Pointer to "struct tomoyo_request_info". - * @fmt: The printf()'s format string, followed by parameters. + * @r: Pointer to "struct tomoyo_request_info". + * @fmt: The printf()'s format string, followed by parameters. * * Returns 0 if the supervisor decided to permit the access request which * violated the policy in enforcing mode, TOMOYO_RETRY_REQUEST if the @@ -1465,88 +1466,77 @@ static atomic_t tomoyo_query_observers = ATOMIC_INIT(0); int tomoyo_supervisor(struct tomoyo_request_info *r, const char *fmt, ...) { va_list args; - int error = -EPERM; - int pos; + int error; int len; static unsigned int tomoyo_serial; - struct tomoyo_query *entry = NULL; + struct tomoyo_query entry = { }; bool quota_exceeded = false; - char *header; + va_start(args, fmt); + len = vsnprintf((char *) &len, 1, fmt, args) + 1; + va_end(args); + /* Write /sys/kernel/security/tomoyo/audit. */ + va_start(args, fmt); + tomoyo_write_log2(r, len, fmt, args); + va_end(args); + /* Nothing more to do if granted. */ + if (r->granted) + return 0; switch (r->mode) { - char *buffer; + case TOMOYO_CONFIG_ENFORCING: + error = -EPERM; + if (atomic_read(&tomoyo_query_observers)) + break; + goto out; case TOMOYO_CONFIG_LEARNING: - if (!tomoyo_domain_quota_is_ok(r)) - return 0; - va_start(args, fmt); - len = vsnprintf((char *) &pos, sizeof(pos) - 1, fmt, args) + 4; - va_end(args); - buffer = kmalloc(len, GFP_NOFS); - if (!buffer) - return 0; - va_start(args, fmt); - vsnprintf(buffer, len - 1, fmt, args); - va_end(args); - tomoyo_normalize_line(buffer); - tomoyo_write_domain2(&r->domain->acl_info_list, buffer, false); - kfree(buffer); + error = 0; + /* Check max_learning_entry parameter. */ + if (tomoyo_domain_quota_is_ok(r)) + break; /* fall through */ - case TOMOYO_CONFIG_PERMISSIVE: + default: return 0; } - if (!r->domain) - r->domain = tomoyo_domain(); - if (!atomic_read(&tomoyo_query_observers)) - return -EPERM; + /* Get message. */ va_start(args, fmt); - len = vsnprintf((char *) &pos, sizeof(pos) - 1, fmt, args) + 32; + entry.query = tomoyo_init_log(r, len, fmt, args); va_end(args); - header = tomoyo_init_audit_log(&len, r); - if (!header) + if (!entry.query) goto out; - entry = kzalloc(sizeof(*entry), GFP_NOFS); - if (!entry) - goto out; - entry->query = kzalloc(len, GFP_NOFS); - if (!entry->query) + entry.query_len = strlen(entry.query) + 1; + if (!error) { + tomoyo_add_entry(r->domain, entry.query); goto out; - len = ksize(entry->query); + } + len = tomoyo_round2(entry.query_len); spin_lock(&tomoyo_query_list_lock); - if (tomoyo_quota_for_query && tomoyo_query_memory_size + len + - sizeof(*entry) >= tomoyo_quota_for_query) { + if (tomoyo_memory_quota[TOMOYO_MEMORY_QUERY] && + tomoyo_memory_used[TOMOYO_MEMORY_QUERY] + len + >= tomoyo_memory_quota[TOMOYO_MEMORY_QUERY]) { quota_exceeded = true; } else { - tomoyo_query_memory_size += len + sizeof(*entry); - entry->serial = tomoyo_serial++; + entry.serial = tomoyo_serial++; + entry.retry = r->retry; + tomoyo_memory_used[TOMOYO_MEMORY_QUERY] += len; + list_add_tail(&entry.list, &tomoyo_query_list); } spin_unlock(&tomoyo_query_list_lock); if (quota_exceeded) goto out; - pos = snprintf(entry->query, len - 1, "Q%u-%hu\n%s", - entry->serial, r->retry, header); - kfree(header); - header = NULL; - va_start(args, fmt); - vsnprintf(entry->query + pos, len - 1 - pos, fmt, args); - entry->query_len = strlen(entry->query) + 1; - va_end(args); - spin_lock(&tomoyo_query_list_lock); - list_add_tail(&entry->list, &tomoyo_query_list); - spin_unlock(&tomoyo_query_list_lock); /* Give 10 seconds for supervisor's opinion. */ - for (entry->timer = 0; - atomic_read(&tomoyo_query_observers) && entry->timer < 100; - entry->timer++) { - wake_up(&tomoyo_query_wait); - set_current_state(TASK_INTERRUPTIBLE); - schedule_timeout(HZ / 10); - if (entry->answer) + while (entry.timer < 10) { + wake_up_all(&tomoyo_query_wait); + if (wait_event_interruptible_timeout + (tomoyo_answer_wait, entry.answer || + !atomic_read(&tomoyo_query_observers), HZ)) break; + else + entry.timer++; } spin_lock(&tomoyo_query_list_lock); - list_del(&entry->list); - tomoyo_query_memory_size -= len + sizeof(*entry); + list_del(&entry.list); + tomoyo_memory_used[TOMOYO_MEMORY_QUERY] -= len; spin_unlock(&tomoyo_query_list_lock); - switch (entry->answer) { + switch (entry.answer) { case 3: /* Asked to retry by administrator. */ error = TOMOYO_RETRY_REQUEST; r->retry++; @@ -1555,18 +1545,12 @@ int tomoyo_supervisor(struct tomoyo_request_info *r, const char *fmt, ...) /* Granted by administrator. */ error = 0; break; - case 0: - /* Timed out. */ - break; default: - /* Rejected by administrator. */ + /* Timed out or rejected by administrator. */ break; } - out: - if (entry) - kfree(entry->query); - kfree(entry); - kfree(header); +out: + kfree(entry.query); return error; } @@ -1637,7 +1621,7 @@ static void tomoyo_read_query(struct tomoyo_io_buffer *head) head->r.query_index = 0; return; } - buf = kzalloc(len, GFP_NOFS); + buf = kzalloc(len + 32, GFP_NOFS); if (!buf) return; pos = 0; @@ -1653,7 +1637,8 @@ static void tomoyo_read_query(struct tomoyo_io_buffer *head) * can change, but I don't care. */ if (len == ptr->query_len) - memmove(buf, ptr->query, len); + snprintf(buf, len + 31, "Q%u-%hu\n%s", ptr->serial, + ptr->retry, ptr->query); break; } spin_unlock(&tomoyo_query_list_lock); @@ -1764,6 +1749,11 @@ int tomoyo_open_control(const u8 type, struct file *file) head->write = tomoyo_write_exception; head->read = tomoyo_read_exception; break; + case TOMOYO_AUDIT: + /* /sys/kernel/security/tomoyo/audit */ + head->poll = tomoyo_poll_log; + head->read = tomoyo_read_log; + break; case TOMOYO_SELFDOMAIN: /* /sys/kernel/security/tomoyo/self_domain */ head->read = tomoyo_read_self_domain; @@ -1837,7 +1827,7 @@ int tomoyo_open_control(const u8 type, struct file *file) return -ENOMEM; } } - if (type != TOMOYO_QUERY) + if (type != TOMOYO_QUERY && type != TOMOYO_AUDIT) head->reader_idx = tomoyo_read_lock(); file->private_data = head; /* @@ -1858,7 +1848,8 @@ int tomoyo_open_control(const u8 type, struct file *file) * @wait: Pointer to "poll_table". * * Waits for read readiness. - * /sys/kernel/security/tomoyo/query is handled by /usr/sbin/tomoyo-queryd . + * /sys/kernel/security/tomoyo/query is handled by /usr/sbin/tomoyo-queryd and + * /sys/kernel/security/tomoyo/audit is handled by /usr/sbin/tomoyo-auditd. */ int tomoyo_poll_control(struct file *file, poll_table *wait) { @@ -1970,7 +1961,7 @@ int tomoyo_close_control(struct tomoyo_io_buffer *head) */ if (head->type == TOMOYO_QUERY) atomic_dec(&tomoyo_query_observers); - else + else if (head->type != TOMOYO_AUDIT) tomoyo_read_unlock(head->reader_idx); /* Release memory used for policy I/O. */ kfree(head->read_buf); -- cgit v1.2.3