Add verify blocks after sync (#715)

Co-authored-by: 杨赫然 <heran.yang@seafile.com>

server/http-server.c

@@ -152,6 +152,7 @@ load_http_config (HttpServerStruct *htp_server, SeafileSession *session)
     int worker_threads;
     char *encoding;
     char *cluster_shared_temp_file_mode = NULL;
+    gboolean verify_client_blocks;
 
     host = fileserver_config_get_string (session->config, HOST, &error);
     if (!error) {
@@ -194,6 +195,18 @@ load_http_config (HttpServerStruct *htp_server, SeafileSession *session)
     }
     seaf_message ("fileserver: worker_threads = %d\n", htp_server->worker_threads);
 
+    verify_client_blocks  = fileserver_config_get_boolean (session->config,
+                                                           "verify_client_blocks_after_sync",
+                                                           &error);
+    if (error) {
+        htp_server->verify_client_blocks = TRUE;
+        g_clear_error(&error);
+    } else {
+        htp_server->verify_client_blocks = verify_client_blocks;
+    }
+    seaf_message ("fileserver: verify_client_blocks = %d\n",
+                  htp_server->verify_client_blocks);
+
     cluster_shared_temp_file_mode = fileserver_config_get_string (session->config,
                                                                   "cluster_shared_temp_file_mode",
                                                                   &error);
@@ -1090,6 +1103,95 @@ out:
     return ret;
 }
 
+typedef struct CheckBlockAux {
+    GList *file_list;
+    const char *store_id;
+    int version;
+} CheckBlockAux;
+
+static int
+check_file_blocks (int n, const char *basedir, SeafDirent *files[], void *data)
+{
+    Seafile *file = NULL;
+    char *block_id;
+    int i = 0;
+    SeafDirent *file1 = files[0];
+    SeafDirent *file2 = files[1];
+    CheckBlockAux *aux = (CheckBlockAux*)data;
+
+    if (!file2 || strcmp (file2->id, EMPTY_SHA1) == 0 || (file1 && strcmp (file1->id, file2->id) == 0)) {
+        return 0;
+    }
+
+    file = seaf_fs_manager_get_seafile (seaf->fs_mgr, aux->store_id, aux->version, file2->id);
+    if (!file) {
+        return -1;
+    }
+
+    for (i = 0; i < file->n_blocks; ++i) {
+        block_id = file->blk_sha1s[i];
+        if (!seaf_block_manager_block_exists (seaf->block_mgr, aux->store_id, aux->version, block_id)) {
+            aux->file_list = g_list_prepend (aux->file_list, g_strdup (file2->name));
+            goto out;
+        }
+    }
+
+out:
+    seafile_unref (file);
+    return 0;
+}
+
+static int
+check_dir_cb (int n, const char *basedir, SeafDirent *dirs[], void *data,
+              gboolean *recurse)
+{
+    return 0;
+}
+
+static int
+check_blocks (SeafRepo *repo, SeafCommit *base, SeafCommit *remote, char **ret_body) {
+    DiffOptions opts;
+    memset (&opts, 0, sizeof(opts));
+    memcpy (opts.store_id, repo->store_id, 36);
+    opts.version = repo->version;
+
+    opts.file_cb = check_file_blocks;
+    opts.dir_cb = check_dir_cb;
+
+    CheckBlockAux aux;
+    memset (&aux, 0, sizeof(aux));
+    aux.store_id = repo->store_id;
+    aux.version = repo->version;
+    opts.data = &aux;
+
+    const char *trees[2];
+    trees[0] = base->root_id;
+    trees[1] = remote->root_id;
+
+    if (diff_trees (2, trees, &opts) < 0) {
+        seaf_warning ("Failed to diff base and remote head for repo %.8s.\n",
+                      repo->id);
+        return -1;
+    }
+
+    if (!aux.file_list) {
+        return 0;
+    }
+
+    json_t *obj_array = json_array ();
+    GList *ptr;
+    for (ptr = aux.file_list; ptr; ptr = ptr->next) {
+        json_array_append_new (obj_array, json_string (ptr->data));
+        g_free (ptr->data);
+    }
+    g_list_free (aux.file_list);
+
+    *ret_body = json_dumps (obj_array, JSON_COMPACT);
+    json_decref (obj_array);
+
+    return -1;
+}
+
 static void
 put_update_branch_cb (evhtp_request_t *req, void *arg)
 {
@@ -1154,6 +1256,19 @@ put_update_branch_cb (evhtp_request_t *req, void *arg)
 
     token = get_auth_token (req);
 
+    if (seaf->http_server->verify_client_blocks) {
+        char *ret_body = NULL;
+        int rc = check_blocks(repo, base, new_commit, &ret_body);
+        if (rc < 0) {
+            if (ret_body) {
+                evbuffer_add (req->buffer_out, ret_body, strlen (ret_body));
+            }
+            evhtp_send_reply (req, SEAF_HTTP_RES_BLOCK_MISSING);
+            g_free (ret_body);
+            goto out;
+        }
+    }
+
     if (fast_forward_or_merge (repo_id, base, new_commit, token) < 0) {
         seaf_warning ("Fast forward merge for repo %s is failed.\n", repo_id);
         evhtp_send_reply (req, EVHTP_RES_SERVERR);