session: Fix crash when the UCI option 'password' or 'username' is missing
[project/rpcd.git] / uci.c
diff --git a/uci.c b/uci.c
index 2d7d430aea2b1b3dc970fa71eaa1f3cd4ee08259..3cd2b829efd055e3096da1499fbf2e70f5f1850b 100644 (file)
--- a/uci.c
+++ b/uci.c
@@ -181,6 +181,60 @@ static const struct blobmsg_policy rpc_uci_rollback_policy[__RPC_B_MAX] = {
                                                .type = BLOBMSG_TYPE_STRING },
 };
 
+/*
+ * Validate a uci name
+ */
+static bool
+rpc_uci_verify_str(const char *name, bool extended, bool type)
+{
+       const char *c;
+       char *e;
+
+       if (!name || !*name)
+               return false;
+
+       if (extended && *name != '@')
+               extended = false;
+
+       for (c = name + extended; *c; c++)
+               if (!isalnum(*c) && *c != '_' && ((!type && !extended) || *c != '-'))
+                       break;
+
+       if (extended) {
+               if (*c != '[')
+                       return false;
+
+               strtol(++c, &e, 10);
+
+               return (e > c && *e == ']' && *(e+1) == 0);
+       }
+
+       return (*c == 0);
+}
+
+/*
+ * Check that string is a valid, shell compatible uci name
+ */
+static bool rpc_uci_verify_name(const char *name) {
+       return rpc_uci_verify_str(name, false, false);
+}
+
+/*
+ * Check that string is a valid section type name
+ */
+static bool rpc_uci_verify_type(const char *type) {
+       return rpc_uci_verify_str(type, false, true);
+}
+
+/*
+ * Check that the string is a valid section id, optionally in extended
+ * lookup notation
+ */
+static bool rpc_uci_verify_section(const char *section) {
+       return rpc_uci_verify_str(section, true, false);
+}
+
+
 /*
  * Turn uci error state into ubus return code
  */
@@ -212,8 +266,12 @@ rpc_uci_replace_savedir(const char *path)
 {
        struct uci_element *e, *tmp;
 
-       uci_foreach_element_safe(&cursor->delta_path, tmp, e)
+       uci_foreach_element_safe(&cursor->delta_path, tmp, e) {
+               if (e->name)
+                       free(e->name);
+
                free(e);
+       }
 
        cursor->delta_path.prev = &cursor->delta_path;
        cursor->delta_path.next = &cursor->delta_path;
@@ -629,7 +687,7 @@ rpc_uci_add(struct ubus_context *ctx, struct ubus_object *obj,
        struct uci_package *p = NULL;
        struct uci_section *s;
        struct uci_ptr ptr = { 0 };
-       int rem, rem2;
+       int rem, rem2, err = 0;
 
        blobmsg_parse(rpc_uci_add_policy, __RPC_A_MAX, tb,
                      blob_data(msg), blob_len(msg));
@@ -640,6 +698,13 @@ rpc_uci_add(struct ubus_context *ctx, struct ubus_object *obj,
        if (!rpc_uci_write_access(tb[RPC_A_SESSION], tb[RPC_A_CONFIG]))
                return UBUS_STATUS_PERMISSION_DENIED;
 
+       if (!rpc_uci_verify_type(blobmsg_data(tb[RPC_A_TYPE])))
+               return UBUS_STATUS_INVALID_ARGUMENT;
+
+       if (tb[RPC_A_NAME] &&
+           !rpc_uci_verify_name(blobmsg_data(tb[RPC_A_NAME])))
+               return UBUS_STATUS_INVALID_ARGUMENT;
+
        ptr.package = blobmsg_data(tb[RPC_A_CONFIG]);
 
        if (uci_load(cursor, ptr.package, &p))
@@ -669,38 +734,73 @@ rpc_uci_add(struct ubus_context *ctx, struct ubus_object *obj,
        {
                blobmsg_for_each_attr(cur, tb[RPC_A_VALUES], rem)
                {
+                       ptr.flags = 0;
                        ptr.o = NULL;
                        ptr.option = blobmsg_name(cur);
 
+                       if (!rpc_uci_verify_name(ptr.option))
+                       {
+                               if (!err)
+                                       err = UBUS_STATUS_INVALID_ARGUMENT;
+
+                               continue;
+                       }
+
                        if (rpc_uci_lookup(&ptr) || !ptr.s)
+                       {
+                               if (!err)
+                                       err = UBUS_STATUS_NOT_FOUND;
+
                                continue;
+                       }
 
                        switch (blobmsg_type(cur))
                        {
                        case BLOBMSG_TYPE_ARRAY:
                                blobmsg_for_each_attr(elem, cur, rem2)
-                                       if (rpc_uci_format_blob(elem, &ptr.value))
-                                               uci_add_list(cursor, &ptr);
+                               {
+                                       if (!rpc_uci_format_blob(elem, &ptr.value))
+                                       {
+                                               if (!err)
+                                                       err = UBUS_STATUS_INVALID_ARGUMENT;
+
+                                               continue;
+                                       }
+
+                                       uci_add_list(cursor, &ptr);
+                               }
+
                                break;
 
                        default:
-                               if (rpc_uci_format_blob(cur, &ptr.value))
+                               if (!rpc_uci_format_blob(cur, &ptr.value))
+                               {
+                                       if (!err)
+                                               err = UBUS_STATUS_INVALID_ARGUMENT;
+                               }
+                               else
+                               {
                                        uci_set(cursor, &ptr);
+                               }
+
                                break;
                        }
                }
        }
 
-       uci_save(cursor, p);
+       if (!err)
+       {
+               uci_save(cursor, p);
 
-       blob_buf_init(&buf, 0);
-       blobmsg_add_string(&buf, "section", ptr.section);
-       ubus_send_reply(ctx, req, buf.head);
+               blob_buf_init(&buf, 0);
+               blobmsg_add_string(&buf, "section", ptr.section);
+               ubus_send_reply(ctx, req, buf.head);
+       }
 
 out:
        uci_unload(cursor, p);
 
-       return rpc_uci_status();
+       return err ? err : rpc_uci_status();
 }
 
 /*
@@ -712,40 +812,63 @@ out:
  *  3) in all other cases only emit a set operation if there is no existing
  *     option of if the existing options value differs from the blob value
  */
-static void
+static int
 rpc_uci_merge_set(struct blob_attr *opt, struct uci_ptr *ptr)
 {
        struct blob_attr *cur;
-       int rem;
+       int rem, rv;
 
+       ptr->flags = 0;
        ptr->o = NULL;
        ptr->option = blobmsg_name(opt);
        ptr->value = NULL;
 
+       if (!rpc_uci_verify_name(ptr->option))
+               return UBUS_STATUS_INVALID_ARGUMENT;
+
        if (rpc_uci_lookup(ptr) || !ptr->s)
-               return;
+               return UBUS_STATUS_NOT_FOUND;
 
        if (blobmsg_type(opt) == BLOBMSG_TYPE_ARRAY)
        {
-               if (ptr->o)
+               if (ptr->o) {
                        uci_delete(cursor, ptr);
+                       ptr->flags = 0;
+               }
+
+               rv = UBUS_STATUS_INVALID_ARGUMENT;
 
                blobmsg_for_each_attr(cur, opt, rem)
-                       if (rpc_uci_format_blob(cur, &ptr->value))
-                               uci_add_list(cursor, ptr);
+               {
+                       if (!rpc_uci_format_blob(cur, &ptr->value))
+                               continue;
+
+                       uci_add_list(cursor, ptr);
+                       rv = 0;
+               }
+
+               return rv;
        }
        else if (ptr->o && ptr->o->type == UCI_TYPE_LIST)
        {
                uci_delete(cursor, ptr);
+               ptr->flags = 0;
 
-               if (rpc_uci_format_blob(opt, &ptr->value))
-                       uci_set(cursor, ptr);
+               if (!rpc_uci_format_blob(opt, &ptr->value))
+                       return UBUS_STATUS_INVALID_ARGUMENT;
+
+               uci_set(cursor, ptr);
        }
-       else if (rpc_uci_format_blob(opt, &ptr->value))
+       else
        {
+               if (!rpc_uci_format_blob(opt, &ptr->value))
+                       return UBUS_STATUS_INVALID_ARGUMENT;
+
                if (!ptr->o || !ptr->o->v.string || strcmp(ptr->o->v.string, ptr->value))
                        uci_set(cursor, ptr);
        }
+
+       return 0;
 }
 
 static int
@@ -758,7 +881,7 @@ rpc_uci_set(struct ubus_context *ctx, struct ubus_object *obj,
        struct uci_package *p = NULL;
        struct uci_element *e;
        struct uci_ptr ptr = { 0 };
-       int rem;
+       int rem, rv, err = 0;
 
        blobmsg_parse(rpc_uci_set_policy, __RPC_S_MAX, tb,
                      blob_data(msg), blob_len(msg));
@@ -770,6 +893,10 @@ rpc_uci_set(struct ubus_context *ctx, struct ubus_object *obj,
        if (!rpc_uci_write_access(tb[RPC_S_SESSION], tb[RPC_S_CONFIG]))
                return UBUS_STATUS_PERMISSION_DENIED;
 
+       if (tb[RPC_S_SECTION] &&
+           !rpc_uci_verify_section(blobmsg_data(tb[RPC_S_SECTION])))
+               return UBUS_STATUS_INVALID_ARGUMENT;
+
        ptr.package = blobmsg_data(tb[RPC_S_CONFIG]);
 
        if (uci_load(cursor, ptr.package, &p))
@@ -779,7 +906,12 @@ rpc_uci_set(struct ubus_context *ctx, struct ubus_object *obj,
        {
                ptr.section = blobmsg_data(tb[RPC_S_SECTION]);
                blobmsg_for_each_attr(cur, tb[RPC_S_VALUES], rem)
-                       rpc_uci_merge_set(cur, &ptr);
+               {
+                       rv = rpc_uci_merge_set(cur, &ptr);
+
+                       if (rv)
+                               err = rv;
+               }
        }
        else
        {
@@ -793,14 +925,24 @@ rpc_uci_set(struct ubus_context *ctx, struct ubus_object *obj,
                        ptr.section = e->name;
 
                        blobmsg_for_each_attr(cur, tb[RPC_S_VALUES], rem)
-                               rpc_uci_merge_set(cur, &ptr);
+                       {
+                               rv = rpc_uci_merge_set(cur, &ptr);
+
+                               if (rv)
+                                       err = rv;
+                       }
                }
        }
 
-       uci_save(cursor, p);
+       if (!err && !ptr.s)
+               err = UBUS_STATUS_NOT_FOUND;
+
+       if (!err)
+               uci_save(cursor, p);
+
        uci_unload(cursor, p);
 
-       return rpc_uci_status();
+       return err ? err : rpc_uci_status();
 }
 
 /*
@@ -809,14 +951,14 @@ rpc_uci_set(struct ubus_context *ctx, struct ubus_object *obj,
  *  2) if the blob is of type string, delete the option named after its value
  *  3) if the blob is NULL, delete entire section
  */
-static void
+static int
 rpc_uci_merge_delete(struct blob_attr *opt, struct uci_ptr *ptr)
 {
        struct blob_attr *cur;
-       int rem;
+       int rem, rv;
 
        if (rpc_uci_lookup(ptr) || !ptr->s)
-               return;
+               return UBUS_STATUS_NOT_FOUND;
 
        if (!opt)
        {
@@ -824,9 +966,12 @@ rpc_uci_merge_delete(struct blob_attr *opt, struct uci_ptr *ptr)
                ptr->option = NULL;
 
                uci_delete(cursor, ptr);
+               return 0;
        }
        else if (blobmsg_type(opt) == BLOBMSG_TYPE_ARRAY)
        {
+               rv = UBUS_STATUS_NOT_FOUND;
+
                blobmsg_for_each_attr(cur, opt, rem)
                {
                        if (blobmsg_type(cur) != BLOBMSG_TYPE_STRING)
@@ -839,7 +984,11 @@ rpc_uci_merge_delete(struct blob_attr *opt, struct uci_ptr *ptr)
                                continue;
 
                        uci_delete(cursor, ptr);
+                       ptr->flags = 0;
+                       rv = 0;
                }
+
+               return rv;
        }
        else if (blobmsg_type(opt) == BLOBMSG_TYPE_STRING)
        {
@@ -847,10 +996,13 @@ rpc_uci_merge_delete(struct blob_attr *opt, struct uci_ptr *ptr)
                ptr->option = blobmsg_data(opt);
 
                if (rpc_uci_lookup(ptr) || !ptr->o)
-                       return;
+                       return UBUS_STATUS_NOT_FOUND;
 
                uci_delete(cursor, ptr);
+               return 0;
        }
+
+       return UBUS_STATUS_INVALID_ARGUMENT;
 }
 
 static int
@@ -862,6 +1014,7 @@ rpc_uci_delete(struct ubus_context *ctx, struct ubus_object *obj,
        struct uci_package *p = NULL;
        struct uci_element *e, *tmp;
        struct uci_ptr ptr = { 0 };
+       int err = 0;
 
        blobmsg_parse(rpc_uci_delete_policy, __RPC_D_MAX, tb,
                      blob_data(msg), blob_len(msg));
@@ -873,6 +1026,14 @@ rpc_uci_delete(struct ubus_context *ctx, struct ubus_object *obj,
        if (!rpc_uci_write_access(tb[RPC_D_SESSION], tb[RPC_D_CONFIG]))
                return UBUS_STATUS_PERMISSION_DENIED;
 
+       if (tb[RPC_D_TYPE] &&
+           !rpc_uci_verify_type(blobmsg_data(tb[RPC_D_TYPE])))
+               return UBUS_STATUS_INVALID_ARGUMENT;
+
+       if (tb[RPC_D_SECTION] &&
+           !rpc_uci_verify_section(blobmsg_data(tb[RPC_D_SECTION])))
+               return UBUS_STATUS_INVALID_ARGUMENT;
+
        ptr.package = blobmsg_data(tb[RPC_D_CONFIG]);
 
        if (uci_load(cursor, ptr.package, &p))
@@ -883,9 +1044,9 @@ rpc_uci_delete(struct ubus_context *ctx, struct ubus_object *obj,
                ptr.section = blobmsg_data(tb[RPC_D_SECTION]);
 
                if (tb[RPC_D_OPTIONS])
-                       rpc_uci_merge_delete(tb[RPC_D_OPTIONS], &ptr);
+                       err = rpc_uci_merge_delete(tb[RPC_D_OPTIONS], &ptr);
                else
-                       rpc_uci_merge_delete(tb[RPC_D_OPTION], &ptr);
+                       err = rpc_uci_merge_delete(tb[RPC_D_OPTION], &ptr);
        }
        else
        {
@@ -899,16 +1060,21 @@ rpc_uci_delete(struct ubus_context *ctx, struct ubus_object *obj,
                        ptr.section = e->name;
 
                        if (tb[RPC_D_OPTIONS])
-                               rpc_uci_merge_delete(tb[RPC_D_OPTIONS], &ptr);
+                               err = rpc_uci_merge_delete(tb[RPC_D_OPTIONS], &ptr);
                        else
-                               rpc_uci_merge_delete(tb[RPC_D_OPTION], &ptr);
+                               err = rpc_uci_merge_delete(tb[RPC_D_OPTION], &ptr);
                }
+
+               if (!err && !ptr.section)
+                       err = UBUS_STATUS_NOT_FOUND;
        }
 
-       uci_save(cursor, p);
+       if (!err)
+               uci_save(cursor, p);
+
        uci_unload(cursor, p);
 
-       return rpc_uci_status();
+       return err ? err : rpc_uci_status();
 }
 
 static int
@@ -933,6 +1099,9 @@ rpc_uci_rename(struct ubus_context *ctx, struct ubus_object *obj,
        ptr.section = blobmsg_data(tb[RPC_R_SECTION]);
        ptr.value   = blobmsg_data(tb[RPC_R_NAME]);
 
+       if (!rpc_uci_verify_name(ptr.value))
+               return UBUS_STATUS_INVALID_ARGUMENT;
+
        if (tb[RPC_R_OPTION])
                ptr.option = blobmsg_data(tb[RPC_R_OPTION]);
 
@@ -968,7 +1137,7 @@ rpc_uci_order(struct ubus_context *ctx, struct ubus_object *obj,
        struct blob_attr *cur;
        struct uci_package *p = NULL;
        struct uci_ptr ptr = { 0 };
-       int rem, i = 1;
+       int rem, i = 0, err = 0;
 
        blobmsg_parse(rpc_uci_order_policy, __RPC_O_MAX, tb,
                      blob_data(msg), blob_len(msg));
@@ -987,21 +1156,33 @@ rpc_uci_order(struct ubus_context *ctx, struct ubus_object *obj,
        blobmsg_for_each_attr(cur, tb[RPC_O_SECTIONS], rem)
        {
                if (blobmsg_type(cur) != BLOBMSG_TYPE_STRING)
+               {
+                       if (!err)
+                               err = UBUS_STATUS_INVALID_ARGUMENT;
+
                        continue;
+               }
 
                ptr.s = NULL;
                ptr.section = blobmsg_data(cur);
 
                if (uci_lookup_ptr(cursor, &ptr, NULL, true) || !ptr.s)
+               {
+                       if (!err)
+                               err = UBUS_STATUS_NOT_FOUND;
+
                        continue;
+               }
 
                uci_reorder_section(cursor, ptr.s, i++);
        }
 
-       uci_save(cursor, p);
+       if (!err)
+               uci_save(cursor, p);
+
        uci_unload(cursor, p);
 
-       return rpc_uci_status();
+       return err ? err : rpc_uci_status();
 }
 
 static void
@@ -1110,6 +1291,8 @@ rpc_uci_changes(struct ubus_context *ctx, struct ubus_object *obj,
                uci_unload(cursor, p);
        }
 
+       free(configs);
+
        blobmsg_close_table(&buf, c);
 
        ubus_send_reply(ctx, req, buf.head);
@@ -1214,6 +1397,8 @@ rpc_uci_configs(struct ubus_context *ctx, struct ubus_object *obj,
        for (i = 0; configs[i]; i++)
                blobmsg_add_string(&buf, NULL, configs[i]);
 
+       free(configs);
+
        blobmsg_close_array(&buf, c);
 
        ubus_send_reply(ctx, req, buf.head);
@@ -1292,17 +1477,53 @@ rpc_uci_copy_file(const char *src, const char *target, const char *file)
                fclose(out);
 }
 
+static int
+rpc_uci_apply_access(const char *sid, glob_t *gl)
+{
+       struct stat s;
+       int i, c = 0;
+
+       if (gl->gl_pathc < 3)
+               return UBUS_STATUS_NO_DATA;
+
+       for (i = 0; i < gl->gl_pathc; i++) {
+               char *config = basename(gl->gl_pathv[i]);
+
+               if (*config == '.')
+                       continue;
+               if (stat(gl->gl_pathv[i], &s) || !s.st_size)
+                       continue;
+               if (!rpc_session_access(sid, "uci", config, "write"))
+                       return UBUS_STATUS_PERMISSION_DENIED;
+               c++;
+       }
+
+       if (!c)
+               return UBUS_STATUS_NO_DATA;
+
+       return 0;
+}
+
 static void
-rpc_uci_do_rollback(struct ubus_context *ctx, const char *sid, glob_t *gl)
+rpc_uci_do_rollback(struct ubus_context *ctx, glob_t *gl)
 {
-       int i;
+       int i, deny;
        char tmp[PATH_MAX];
 
-       if (sid) {
-               snprintf(tmp, sizeof(tmp), RPC_UCI_SAVEDIR_PREFIX "%s/", sid);
+       /* Test apply permission to see if the initiator session still exists.
+        * If it does, restore the delta files as well, else just restore the
+        * main configuration files. */
+       deny = apply_sid[0]
+               ? rpc_uci_apply_access(apply_sid, gl) : UBUS_STATUS_NOT_FOUND;
+
+       if (!deny) {
+               snprintf(tmp, sizeof(tmp), RPC_UCI_SAVEDIR_PREFIX "%s/", apply_sid);
                mkdir(tmp, 0700);
        }
 
+       /* avoid merging unrelated uci changes when restoring old configs */
+       rpc_uci_replace_savedir("/dev/null");
+
        for (i = 0; i < gl->gl_pathc; i++) {
                char *config = basename(gl->gl_pathv[i]);
 
@@ -1311,8 +1532,11 @@ rpc_uci_do_rollback(struct ubus_context *ctx, const char *sid, glob_t *gl)
 
                rpc_uci_copy_file(RPC_SNAPSHOT_FILES, RPC_UCI_DIR, config);
                rpc_uci_apply_config(ctx, config);
-               if (sid)
-                       rpc_uci_copy_file(RPC_SNAPSHOT_DELTA, tmp, config);
+
+               if (deny)
+                       continue;
+
+               rpc_uci_copy_file(RPC_SNAPSHOT_DELTA, tmp, config);
        }
 
        rpc_uci_purge_dir(RPC_SNAPSHOT_FILES);
@@ -1333,34 +1557,9 @@ rpc_uci_apply_timeout(struct uloop_timeout *t)
        if (glob(tmp, GLOB_PERIOD, NULL, &gl) < 0)
                return;
 
-       rpc_uci_do_rollback(apply_ctx, NULL, &gl);
-}
-
-static int
-rpc_uci_apply_access(const char *sid, glob_t *gl)
-{
-       struct stat s;
-       int i, c = 0;
-
-       if (gl->gl_pathc < 3)
-               return UBUS_STATUS_NO_DATA;
-
-       for (i = 0; i < gl->gl_pathc; i++) {
-               char *config = basename(gl->gl_pathv[i]);
-
-               if (*config == '.')
-                       continue;
-               if (stat(gl->gl_pathv[i], &s) || !s.st_size)
-                       continue;
-               if (!rpc_session_access(sid, "uci", config, "write"))
-                       return UBUS_STATUS_PERMISSION_DENIED;
-               c++;
-       }
-
-       if (!c)
-               return UBUS_STATUS_NO_DATA;
+       rpc_uci_do_rollback(apply_ctx, &gl);
 
-       return 0;
+       globfree(&gl);
 }
 
 static int
@@ -1397,6 +1596,8 @@ rpc_uci_apply(struct ubus_context *ctx, struct ubus_object *obj,
        rpc_uci_purge_dir(RPC_SNAPSHOT_DELTA);
 
        if (!apply_sid[0]) {
+               rpc_uci_set_savedir(tb[RPC_T_SESSION]);
+
                mkdir(RPC_SNAPSHOT_FILES, 0700);
                mkdir(RPC_SNAPSHOT_DELTA, 0700);
 
@@ -1503,7 +1704,7 @@ rpc_uci_rollback(struct ubus_context *ctx, struct ubus_object *obj,
        if (glob(tmp, GLOB_PERIOD, NULL, &gl) < 0)
                return UBUS_STATUS_NOT_FOUND;
 
-       rpc_uci_do_rollback(ctx, sid, &gl);
+       rpc_uci_do_rollback(ctx, &gl);
 
        globfree(&gl);
 
@@ -1577,7 +1778,7 @@ int rpc_uci_api_init(struct ubus_context *ctx)
        };
 
        static struct ubus_object_type uci_type =
-               UBUS_OBJECT_TYPE("luci-rpc-uci", uci_methods);
+               UBUS_OBJECT_TYPE("rpcd-plugin-uci", uci_methods);
 
        static struct ubus_object obj = {
                .name = "uci",