1 files changed, 419 insertions, 7 deletions

diff --git a/security/tomoyo/common.c b/security/tomoyo/common.c
index 0c6f9a5c37a5..ee46aaa3566f 100644
--- a/security/tomoyo/common.c
+++ b/security/tomoyo/common.c
@@ -74,6 +74,8 @@ static int tomoyo_read_control(struct file *file, char __user *buffer,
 /* Write operation for /sys/kernel/security/tomoyo/ interface. */
 static int tomoyo_write_control(struct file *file, const char __user *buffer,
                                 const int buffer_len);
+/* Check whether the domain has too many ACL entries to hold. */
+static bool tomoyo_domain_quota_is_ok(struct tomoyo_request_info *r);
 
 /**
  * tomoyo_parse_name_union - Parse a tomoyo_name_union.
@@ -1031,7 +1033,7 @@ bool tomoyo_verbose_mode(const struct tomoyo_domain_info *domain)
  *
  * Caller holds tomoyo_read_lock().
  */
-bool tomoyo_domain_quota_is_ok(struct tomoyo_request_info *r)
+static bool tomoyo_domain_quota_is_ok(struct tomoyo_request_info *r)
 {
         unsigned int count = 0;
         struct tomoyo_domain_info *domain = r->domain;
@@ -1531,6 +1533,24 @@ static int tomoyo_delete_domain(char *domainname)
 }
 
 /**
+ * tomoyo_write_domain_policy2 - Write domain policy.
+ *
+ * @head: Pointer to "struct tomoyo_io_buffer".
+ *
+ * Returns 0 on success, negative value otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
+ */
+static int tomoyo_write_domain_policy2(char *data,
+                                       struct tomoyo_domain_info *domain,
+                                       const bool is_delete)
+{
+        if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_ALLOW_MOUNT))
+                return tomoyo_write_mount_policy(data, domain, is_delete);
+        return tomoyo_write_file_policy(data, domain, is_delete);
+}
+
+/**
  * tomoyo_write_domain_policy - Write domain policy.
  *
  * @head: Pointer to "struct tomoyo_io_buffer".
@@ -1580,9 +1600,7 @@ static int tomoyo_write_domain_policy(struct tomoyo_io_buffer *head)
                 domain->ignore_global_allow_read = !is_delete;
                 return 0;
         }
-        if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_ALLOW_MOUNT))
-                return tomoyo_write_mount_policy(data, domain, is_delete);
-        return tomoyo_write_file_policy(data, domain, is_delete);
+        return tomoyo_write_domain_policy2(data, domain, is_delete);
 }
 
 /**
@@ -2186,6 +2204,357 @@ void tomoyo_load_policy(const char *filename)
 }
 
 /**
+ * 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)
+{
+        static const char *tomoyo_mode_4[4] = {
+                "disabled", "learning", "permissive", "enforcing"
+        };
+        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);
+        if (!buffer)
+                return NULL;
+        do_gettimeofday(&tv);
+        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_4[r->mode], gpid,
+                 (pid_t) sys_getpid(), (pid_t) sys_getppid(),
+                 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. */
+static DECLARE_WAIT_QUEUE_HEAD(tomoyo_query_wait);
+
+/* Lock for manipulating tomoyo_query_list. */
+static DEFINE_SPINLOCK(tomoyo_query_list_lock);
+
+/* Structure for query. */
+struct tomoyo_query_entry {
+        struct list_head list;
+        char *query;
+        int query_len;
+        unsigned int serial;
+        int timer;
+        int answer;
+};
+
+/* The list for "struct tomoyo_query_entry". */
+static LIST_HEAD(tomoyo_query_list);
+
+/*
+ * Number of "struct file" referring /sys/kernel/security/tomoyo/query
+ * interface.
+ */
+static atomic_t tomoyo_query_observers = ATOMIC_INIT(0);
+
+/**
+ * tomoyo_supervisor - Ask for the supervisor's decision.
+ *
+ * @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
+ * supervisor decided to retry the access request which violated the policy in
+ * enforcing mode, 0 if it is not in enforcing mode, -EPERM otherwise.
+ */
+int tomoyo_supervisor(struct tomoyo_request_info *r, const char *fmt, ...)
+{
+        va_list args;
+        int error = -EPERM;
+        int pos;
+        int len;
+        static unsigned int tomoyo_serial;
+        struct tomoyo_query_entry *tomoyo_query_entry = NULL;
+        bool quota_exceeded = false;
+        char *header;
+        switch (r->mode) {
+                char *buffer;
+        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_domain_policy2(buffer, r->domain, false);
+                kfree(buffer);
+                /* fall through */
+        case TOMOYO_CONFIG_PERMISSIVE:
+                return 0;
+        }
+        if (!r->domain)
+                r->domain = tomoyo_domain();
+        if (!atomic_read(&tomoyo_query_observers))
+                return -EPERM;
+        va_start(args, fmt);
+        len = vsnprintf((char *) &pos, sizeof(pos) - 1, fmt, args) + 32;
+        va_end(args);
+        header = tomoyo_init_audit_log(&len, r);
+        if (!header)
+                goto out;
+        tomoyo_query_entry = kzalloc(sizeof(*tomoyo_query_entry), GFP_NOFS);
+        if (!tomoyo_query_entry)
+                goto out;
+        tomoyo_query_entry->query = kzalloc(len, GFP_NOFS);
+        if (!tomoyo_query_entry->query)
+                goto out;
+        len = ksize(tomoyo_query_entry->query);
+        INIT_LIST_HEAD(&tomoyo_query_entry->list);
+        spin_lock(&tomoyo_query_list_lock);
+        if (tomoyo_quota_for_query && tomoyo_query_memory_size + len +
+            sizeof(*tomoyo_query_entry) >= tomoyo_quota_for_query) {
+                quota_exceeded = true;
+        } else {
+                tomoyo_query_memory_size += len + sizeof(*tomoyo_query_entry);
+                tomoyo_query_entry->serial = tomoyo_serial++;
+        }
+        spin_unlock(&tomoyo_query_list_lock);
+        if (quota_exceeded)
+                goto out;
+        pos = snprintf(tomoyo_query_entry->query, len - 1, "Q%u-%hu\n%s",
+                       tomoyo_query_entry->serial, r->retry, header);
+        kfree(header);
+        header = NULL;
+        va_start(args, fmt);
+        vsnprintf(tomoyo_query_entry->query + pos, len - 1 - pos, fmt, args);
+        tomoyo_query_entry->query_len = strlen(tomoyo_query_entry->query) + 1;
+        va_end(args);
+        spin_lock(&tomoyo_query_list_lock);
+        list_add_tail(&tomoyo_query_entry->list, &tomoyo_query_list);
+        spin_unlock(&tomoyo_query_list_lock);
+        /* Give 10 seconds for supervisor's opinion. */
+        for (tomoyo_query_entry->timer = 0;
+             atomic_read(&tomoyo_query_observers) && tomoyo_query_entry->timer < 100;
+             tomoyo_query_entry->timer++) {
+                wake_up(&tomoyo_query_wait);
+                set_current_state(TASK_INTERRUPTIBLE);
+                schedule_timeout(HZ / 10);
+                if (tomoyo_query_entry->answer)
+                        break;
+        }
+        spin_lock(&tomoyo_query_list_lock);
+        list_del(&tomoyo_query_entry->list);
+        tomoyo_query_memory_size -= len + sizeof(*tomoyo_query_entry);
+        spin_unlock(&tomoyo_query_list_lock);
+        switch (tomoyo_query_entry->answer) {
+        case 3: /* Asked to retry by administrator. */
+                error = TOMOYO_RETRY_REQUEST;
+                r->retry++;
+                break;
+        case 1:
+                /* Granted by administrator. */
+                error = 0;
+                break;
+        case 0:
+                /* Timed out. */
+                break;
+        default:
+                /* Rejected by administrator. */
+                break;
+        }
+ out:
+        if (tomoyo_query_entry)
+                kfree(tomoyo_query_entry->query);
+        kfree(tomoyo_query_entry);
+        kfree(header);
+        return error;
+}
+
+/**
+ * tomoyo_poll_query - poll() for /sys/kernel/security/tomoyo/query.
+ *
+ * @file: Pointer to "struct file".
+ * @wait: Pointer to "poll_table".
+ *
+ * Returns POLLIN | POLLRDNORM when ready to read, 0 otherwise.
+ *
+ * Waits for access requests which violated policy in enforcing mode.
+ */
+static int tomoyo_poll_query(struct file *file, poll_table *wait)
+{
+        struct list_head *tmp;
+        bool found = false;
+        u8 i;
+        for (i = 0; i < 2; i++) {
+                spin_lock(&tomoyo_query_list_lock);
+                list_for_each(tmp, &tomoyo_query_list) {
+                        struct tomoyo_query_entry *ptr
+                                = list_entry(tmp, struct tomoyo_query_entry,
+                                             list);
+                        if (ptr->answer)
+                                continue;
+                        found = true;
+                        break;
+                }
+                spin_unlock(&tomoyo_query_list_lock);
+                if (found)
+                        return POLLIN | POLLRDNORM;
+                if (i)
+                        break;
+                poll_wait(file, &tomoyo_query_wait, wait);
+        }
+        return 0;
+}
+
+/**
+ * tomoyo_read_query - Read access requests which violated policy in enforcing mode.
+ *
+ * @head: Pointer to "struct tomoyo_io_buffer".
+ *
+ * Returns 0.
+ */
+static int tomoyo_read_query(struct tomoyo_io_buffer *head)
+{
+        struct list_head *tmp;
+        int pos = 0;
+        int len = 0;
+        char *buf;
+        if (head->read_avail)
+                return 0;
+        if (head->read_buf) {
+                kfree(head->read_buf);
+                head->read_buf = NULL;
+                head->readbuf_size = 0;
+        }
+        spin_lock(&tomoyo_query_list_lock);
+        list_for_each(tmp, &tomoyo_query_list) {
+                struct tomoyo_query_entry *ptr
+                        = list_entry(tmp, struct tomoyo_query_entry, list);
+                if (ptr->answer)
+                        continue;
+                if (pos++ != head->read_step)
+                        continue;
+                len = ptr->query_len;
+                break;
+        }
+        spin_unlock(&tomoyo_query_list_lock);
+        if (!len) {
+                head->read_step = 0;
+                return 0;
+        }
+        buf = kzalloc(len, GFP_NOFS);
+        if (!buf)
+                return 0;
+        pos = 0;
+        spin_lock(&tomoyo_query_list_lock);
+        list_for_each(tmp, &tomoyo_query_list) {
+                struct tomoyo_query_entry *ptr
+                        = list_entry(tmp, struct tomoyo_query_entry, list);
+                if (ptr->answer)
+                        continue;
+                if (pos++ != head->read_step)
+                        continue;
+                /*
+                 * Some query can be skipped because tomoyo_query_list
+                 * can change, but I don't care.
+                 */
+                if (len == ptr->query_len)
+                        memmove(buf, ptr->query, len);
+                break;
+        }
+        spin_unlock(&tomoyo_query_list_lock);
+        if (buf[0]) {
+                head->read_avail = len;
+                head->readbuf_size = head->read_avail;
+                head->read_buf = buf;
+                head->read_step++;
+        } else {
+                kfree(buf);
+        }
+        return 0;
+}
+
+/**
+ * tomoyo_write_answer - Write the supervisor's decision.
+ *
+ * @head: Pointer to "struct tomoyo_io_buffer".
+ *
+ * Returns 0 on success, -EINVAL otherwise.
+ */
+static int tomoyo_write_answer(struct tomoyo_io_buffer *head)
+{
+        char *data = head->write_buf;
+        struct list_head *tmp;
+        unsigned int serial;
+        unsigned int answer;
+        spin_lock(&tomoyo_query_list_lock);
+        list_for_each(tmp, &tomoyo_query_list) {
+                struct tomoyo_query_entry *ptr
+                        = list_entry(tmp, struct tomoyo_query_entry, list);
+                ptr->timer = 0;
+        }
+        spin_unlock(&tomoyo_query_list_lock);
+        if (sscanf(data, "A%u=%u", &serial, &answer) != 2)
+                return -EINVAL;
+        spin_lock(&tomoyo_query_list_lock);
+        list_for_each(tmp, &tomoyo_query_list) {
+                struct tomoyo_query_entry *ptr
+                        = list_entry(tmp, struct tomoyo_query_entry, list);
+                if (ptr->serial != serial)
+                        continue;
+                if (!ptr->answer)
+                        ptr->answer = answer;
+                break;
+        }
+        spin_unlock(&tomoyo_query_list_lock);
+        return 0;
+}
+
+/**
  * tomoyo_read_version: Get version.
  *
  * @head: Pointer to "struct tomoyo_io_buffer".
@@ -2239,6 +2608,7 @@ static int tomoyo_open_control(const u8 type, struct file *file)
         if (!head)
                 return -ENOMEM;
         mutex_init(&head->io_sem);
+        head->type = type;
         switch (type) {
         case TOMOYO_DOMAINPOLICY:
                 /* /sys/kernel/security/tomoyo/domain_policy */
@@ -2280,6 +2650,11 @@ static int tomoyo_open_control(const u8 type, struct file *file)
                 head->write = tomoyo_write_profile;
                 head->read = tomoyo_read_profile;
                 break;
+        case TOMOYO_QUERY: /* /sys/kernel/security/tomoyo/query */
+                head->poll = tomoyo_poll_query;
+                head->write = tomoyo_write_answer;
+                head->read = tomoyo_read_query;
+                break;
         case TOMOYO_MANAGER:
                 /* /sys/kernel/security/tomoyo/manager */
                 head->write = tomoyo_write_manager_policy;
@@ -2292,7 +2667,9 @@ static int tomoyo_open_control(const u8 type, struct file *file)
                  * for reading.
                  */
                 head->read = NULL;
-        } else {
+                head->poll = NULL;
+        } else if (!head->poll) {
+                /* Don't allocate read_buf for poll() access. */
                 if (!head->readbuf_size)
                         head->readbuf_size = 4096 * 2;
                 head->read_buf = kzalloc(head->readbuf_size, GFP_NOFS);
@@ -2316,7 +2693,8 @@ static int tomoyo_open_control(const u8 type, struct file *file)
                         return -ENOMEM;
                 }
         }
-        head->reader_idx = tomoyo_read_lock();
+        if (type != TOMOYO_QUERY)
+                head->reader_idx = tomoyo_read_lock();
         file->private_data = head;
         /*
          * Call the handler now if the file is
@@ -2327,10 +2705,35 @@ static int tomoyo_open_control(const u8 type, struct file *file)
          */
         if (type == TOMOYO_SELFDOMAIN)
                 tomoyo_read_control(file, NULL, 0);
+        /*
+         * If the file is /sys/kernel/security/tomoyo/query , increment the
+         * observer counter.
+         * The obserber counter is used by tomoyo_supervisor() to see if
+         * there is some process monitoring /sys/kernel/security/tomoyo/query.
+         */
+        else if (type == TOMOYO_QUERY)
+                atomic_inc(&tomoyo_query_observers);
         return 0;
 }
 
 /**
+ * tomoyo_poll_control - poll() for /sys/kernel/security/tomoyo/ interface.
+ *
+ * @file: Pointer to "struct file".
+ * @wait: Pointer to "poll_table".
+ *
+ * Waits for read readiness.
+ * /sys/kernel/security/tomoyo/query is handled by /usr/sbin/tomoyo-queryd .
+ */
+int tomoyo_poll_control(struct file *file, poll_table *wait)
+{
+        struct tomoyo_io_buffer *head = file->private_data;
+        if (!head->poll)
+                return -ENOSYS;
+        return head->poll(file, wait);
+}
+
+/**
  * tomoyo_read_control - read() for /sys/kernel/security/tomoyo/ interface.
  *
  * @file:       Pointer to "struct file".
@@ -2443,7 +2846,14 @@ static int tomoyo_close_control(struct file *file)
         struct tomoyo_io_buffer *head = file->private_data;
         const bool is_write = !!head->write_buf;
 
-        tomoyo_read_unlock(head->reader_idx);
+        /*
+         * If the file is /sys/kernel/security/tomoyo/query , decrement the
+         * observer counter.
+         */
+        if (head->type == TOMOYO_QUERY)
+                atomic_dec(&tomoyo_query_observers);
+        else
+                tomoyo_read_unlock(head->reader_idx);
         /* Release memory used for policy I/O. */
         kfree(head->read_buf);
         head->read_buf = NULL;
@@ -2562,6 +2972,8 @@ static int __init tomoyo_initerface_init(void)
                 return 0;
 
         tomoyo_dir = securityfs_create_dir("tomoyo", NULL);
+        tomoyo_create_entry("query",            0600, tomoyo_dir,
+                            TOMOYO_QUERY);
         tomoyo_create_entry("domain_policy",    0600, tomoyo_dir,
                             TOMOYO_DOMAINPOLICY);
         tomoyo_create_entry("exception_policy", 0600, tomoyo_dir,