TOMOYO: Use common code for open and mkdir etc.

tomoyo_file_perm() and tomoyo_path_permission() are similar.
We can embed tomoyo_file_perm() into tomoyo_path_permission().

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>

3 files changed, 22 insertions, 84 deletions

diff --git a/security/tomoyo/common.h b/security/tomoyo/common.h
index c8ab7553c48c..203454025410 100644
--- a/security/tomoyo/common.h
+++ b/security/tomoyo/common.h
@@ -880,7 +880,7 @@ int tomoyo_write_memory_quota(struct tomoyo_io_buffer *head);
 
 /* Initialize mm related code. */
 void __init tomoyo_mm_init(void);
-int tomoyo_check_exec_perm(struct tomoyo_request_info *r,
+int tomoyo_path_permission(struct tomoyo_request_info *r, u8 operation,
                            const struct tomoyo_path_info *filename);
 int tomoyo_check_open_permission(struct tomoyo_domain_info *domain,
                                  struct path *path, const int flag);
diff --git a/security/tomoyo/domain.c b/security/tomoyo/domain.c
index fe621af46c2e..35317e783f34 100644
--- a/security/tomoyo/domain.c
+++ b/security/tomoyo/domain.c
@@ -960,7 +960,7 @@ int tomoyo_find_next_domain(struct linux_binprm *bprm)
         }
 
         /* Check execute permission. */
-        retval = tomoyo_check_exec_perm(&r, &rn);
+        retval = tomoyo_path_permission(&r, TOMOYO_TYPE_EXECUTE, &rn);
         if (retval == TOMOYO_RETRY_REQUEST)
                 goto retry;
         if (retval < 0)
diff --git a/security/tomoyo/file.c b/security/tomoyo/file.c
index 8015719926d5..50875d7e8603 100644
--- a/security/tomoyo/file.c
+++ b/security/tomoyo/file.c
@@ -670,62 +670,6 @@ static int tomoyo_path_acl(const struct tomoyo_request_info *r,
         return error;
 }
 
-/**
- * tomoyo_file_perm - Check permission for opening files.
- *
- * @r:         Pointer to "struct tomoyo_request_info".
- * @filename:  Filename to check.
- * @mode:      Mode ("read" or "write" or "read/write" or "execute").
- *
- * Returns 0 on success, negative value otherwise.
- *
- * Caller holds tomoyo_read_lock().
- */
-static int tomoyo_file_perm(struct tomoyo_request_info *r,
-                            const struct tomoyo_path_info *filename,
-                            const u8 mode)
-{
-        const char *msg = "<unknown>";
-        int error = 0;
-        u32 perm = 0;
-
-        if (!filename)
-                return 0;
-
-        if (mode == 6) {
-                msg = tomoyo_path2keyword(TOMOYO_TYPE_READ_WRITE);
-                perm = 1 << TOMOYO_TYPE_READ_WRITE;
-        } else if (mode == 4) {
-                msg = tomoyo_path2keyword(TOMOYO_TYPE_READ);
-                perm = 1 << TOMOYO_TYPE_READ;
-        } else if (mode == 2) {
-                msg = tomoyo_path2keyword(TOMOYO_TYPE_WRITE);
-                perm = 1 << TOMOYO_TYPE_WRITE;
-        } else if (mode == 1) {
-                msg = tomoyo_path2keyword(TOMOYO_TYPE_EXECUTE);
-                perm = 1 << TOMOYO_TYPE_EXECUTE;
-        } else
-                BUG();
-        do {
-                error = tomoyo_path_acl(r, filename, perm);
-                if (error && mode == 4 && !r->domain->ignore_global_allow_read
-                    && tomoyo_is_globally_readable_file(filename))
-                        error = 0;
-                if (!error)
-                        break;
-                tomoyo_warn_log(r, "%s %s", msg, filename->name);
-                error = tomoyo_supervisor(r, "allow_%s %s\n", msg,
-                                          tomoyo_file_pattern(filename));
-                /*
-                 * Do not retry for execute request, for alias may have
-                 * changed.
-                 */
-        } while (error == TOMOYO_RETRY_REQUEST && mode != 1);
-        if (r->mode != TOMOYO_CONFIG_ENFORCING)
-                error = 0;
-        return error;
-}
-
 static bool tomoyo_same_path_acl(const struct tomoyo_acl_info *a,
                                  const struct tomoyo_acl_info *b)
 {
@@ -1018,8 +962,8 @@ static int tomoyo_path2_acl(const struct tomoyo_request_info *r, const u8 type,
  *
  * Caller holds tomoyo_read_lock().
  */
-static int tomoyo_path_permission(struct tomoyo_request_info *r, u8 operation,
-                                  const struct tomoyo_path_info *filename)
+int tomoyo_path_permission(struct tomoyo_request_info *r, u8 operation,
+                           const struct tomoyo_path_info *filename)
 {
         const char *msg;
         int error;
@@ -1031,15 +975,22 @@ static int tomoyo_path_permission(struct tomoyo_request_info *r, u8 operation,
                 return 0;
         do {
                 error = tomoyo_path_acl(r, filename, 1 << operation);
+                if (error && operation == TOMOYO_TYPE_READ &&
+                    !r->domain->ignore_global_allow_read &&
+                    tomoyo_is_globally_readable_file(filename))
+                        error = 0;
                 if (!error)
                         break;
                 msg = tomoyo_path2keyword(operation);
                 tomoyo_warn_log(r, "%s %s", msg, filename->name);
                 error = tomoyo_supervisor(r, "allow_%s %s\n", msg,
                                           tomoyo_file_pattern(filename));
-        } while (error == TOMOYO_RETRY_REQUEST);
-        if (r->mode != TOMOYO_CONFIG_ENFORCING)
-                error = 0;
+                /*
+                 * Do not retry for execute request, for alias may have
+                 * changed.
+                 */
+        } while (error == TOMOYO_RETRY_REQUEST &&
+                 operation != TOMOYO_TYPE_EXECUTE);
         /*
          * Since "allow_truncate" doesn't imply "allow_rewrite" permission,
          * we need to check "allow_rewrite" permission if the filename is
@@ -1202,8 +1153,6 @@ static int tomoyo_path_number_perm2(struct tomoyo_request_info *r,
                                           tomoyo_file_pattern(filename),
                                           buffer);
         } while (error == TOMOYO_RETRY_REQUEST);
-        if (r->mode != TOMOYO_CONFIG_ENFORCING)
-                error = 0;
         return error;
 }
 
@@ -1242,24 +1191,6 @@ int tomoyo_path_number_perm(const u8 type, struct path *path,
 }
 
 /**
- * tomoyo_check_exec_perm - Check permission for "execute".
- *
- * @r:        Pointer to "struct tomoyo_request_info".
- * @filename: Check permission for "execute".
- *
- * Returns 0 on success, negativevalue otherwise.
- *
- * Caller holds tomoyo_read_lock().
- */
-int tomoyo_check_exec_perm(struct tomoyo_request_info *r,
-                           const struct tomoyo_path_info *filename)
-{
-        if (r->mode == TOMOYO_CONFIG_DISABLED)
-                return 0;
-        return tomoyo_file_perm(r, filename, 1);
-}
-
-/**
  * tomoyo_check_open_permission - Check permission for "read" and "write".
  *
  * @domain: Pointer to "struct tomoyo_domain_info".
@@ -1305,11 +1236,18 @@ int tomoyo_check_open_permission(struct tomoyo_domain_info *domain,
         if (!error && acc_mode &&
             tomoyo_init_request_info(&r, domain, TOMOYO_MAC_FILE_OPEN)
             != TOMOYO_CONFIG_DISABLED) {
+                u8 operation;
                 if (!buf.name && !tomoyo_get_realpath(&buf, path)) {
                         error = -ENOMEM;
                         goto out;
                 }
-                error = tomoyo_file_perm(&r, &buf, acc_mode);
+                if (acc_mode == (MAY_READ | MAY_WRITE))
+                        operation = TOMOYO_TYPE_READ_WRITE;
+                else if (acc_mode == MAY_READ)
+                        operation = TOMOYO_TYPE_READ;
+                else
+                        operation = TOMOYO_TYPE_WRITE;
+                error = tomoyo_path_permission(&r, operation, &buf);
         }
  out:
         kfree(buf.name);