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-rw-r--r--security/tomoyo/common.c426
1 files changed, 419 insertions, 7 deletions
diff --git a/security/tomoyo/common.c b/security/tomoyo/common.c
index 0c6f9a5c37a..ee46aaa3566 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,