/* * Copyright (C) 2015 "IoT.bzh" * Author "Fulup Ar Foll" * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . * * Contain all generic part to handle REST/API * * https://www.gnu.org/software/libmicrohttpd/tutorial.html [search 'largepost.c'] */ #include "../include/local-def.h" #include #include #include #include #define AFB_MSG_JTYPE "AJB_reply" static json_object *afbJsonType; // Because of POST call multiple time requestApi we need to free POST handle here // Note this method is called from http-svc just before closing session PUBLIC void endPostRequest(AFB_PostHandle *postHandle) { if (postHandle->type == AFB_POST_JSON) { // if (verbose) fprintf(stderr, "End PostJson Request UID=%d\n", postHandle->uid); } if (postHandle->type == AFB_POST_FORM) { if (verbose) fprintf(stderr, "End PostForm Request UID=%d\n", postHandle->uid); } free(postHandle->private); free(postHandle); } // Check of apiurl is declare in this plugin and call it STATIC AFB_error callPluginApi(AFB_request *request, int plugidx, void *context) { json_object *jresp, *jcall; int idx, status, sig; AFB_clientCtx *clientCtx; AFB_plugin *plugin = request->plugins[plugidx]; int signals[]= {SIGALRM, SIGSEGV, SIGFPE, 0}; /*--------------------------------------------------------------- | Signal handler defined inside CallPluginApi to access Request +---------------------------------------------------------------- */ void pluginError (int signum) { sigset_t sigset; // unlock signal to allow a new signal to come sigemptyset (&sigset); sigaddset (&sigset, signum); sigprocmask (SIG_UNBLOCK, &sigset, 0); fprintf (stderr, "Oops:%s Plugin Api Timeout timeout\n", configTime()); longjmp (request->checkPluginCall, signum); } // If a plugin hold this urlpath call its callback for (idx = 0; plugin->apis[idx].callback != NULL; idx++) { if (!strcmp(plugin->apis[idx].name, request->api)) { // Request was found and at least partially executed request->jresp = json_object_new_object(); json_object_get (afbJsonType); // increate jsontype reference count json_object_object_add (request->jresp, "jtype", afbJsonType); // prepare an object to store calling values jcall=json_object_new_object(); json_object_object_add(jcall, "prefix", json_object_new_string (plugin->prefix)); json_object_object_add(jcall, "api" , json_object_new_string (plugin->apis[idx].name)); // save context before calling the API status = setjmp (request->checkPluginCall); if (status != 0) { // Plugin aborted somewhere during its execution json_object_object_add(jcall, "status", json_object_new_string ("abort")); json_object_object_add(jcall, "info" , json_object_new_string ("Plugin broke during execution")); json_object_object_add(request->jresp, "request", jcall); } else { // If timeout protection==0 we are in debug and we do not apply signal protection if (request->config->apiTimeout > 0) { for (sig=0; signals[sig] != 0; sig++) { if (signal (signals[sig], pluginError) == SIG_ERR) { request->errcode = MHD_HTTP_UNPROCESSABLE_ENTITY; json_object_object_add(jcall, "status", json_object_new_string ("fail")); json_object_object_add(jcall, "info", json_object_new_string ("Setting Timeout Handler Failed")); json_object_object_add(request->jresp, "request", jcall); return AFB_DONE; } } // Trigger a timer to protect from unacceptable long time execution alarm (request->config->apiTimeout); } // Out of SessionNone every call get a client context session if (AFB_SESSION_NONE != plugin->apis[idx].session) { // add client context to request clientCtx = ctxClientGet(request, plugidx); if (clientCtx == NULL) { request->errcode=MHD_HTTP_INSUFFICIENT_STORAGE; json_object_object_add(jcall, "status", json_object_new_string ("fail")); json_object_object_add(jcall, "info", json_object_new_string ("Client Session Context Full !!!")); json_object_object_add(request->jresp, "request", jcall); return (AFB_DONE); }; if (verbose) fprintf(stderr, "Plugin=[%s] Api=[%s] Middleware=[%d] Client=[0x%x] Uuid=[%s] Token=[%s]\n" , request->prefix, request->api, plugin->apis[idx].session, clientCtx, clientCtx->uuid, clientCtx->token); switch(plugin->apis[idx].session) { case AFB_SESSION_CREATE: if (clientCtx->token[0] != '\0') { request->errcode=MHD_HTTP_UNAUTHORIZED; json_object_object_add(jcall, "status", json_object_new_string ("exist")); json_object_object_add(jcall, "info", json_object_new_string ("AFB_SESSION_CREATE Session already exist")); json_object_object_add(request->jresp, "request", jcall); return (AFB_DONE); } if (AFB_SUCCESS != ctxTokenCreate (clientCtx, request)) { request->errcode=MHD_HTTP_UNAUTHORIZED; json_object_object_add(jcall, "status", json_object_new_string ("fail")); json_object_object_add(jcall, "info", json_object_new_string ("AFB_SESSION_CREATE Invalid Initial Token")); json_object_object_add(request->jresp, "request", jcall); return (AFB_DONE); } else { json_object_object_add(jcall, "uuid", json_object_new_string (clientCtx->uuid)); json_object_object_add(jcall, "token", json_object_new_string (clientCtx->token)); json_object_object_add(jcall, "timeout", json_object_new_int (request->config->cntxTimeout)); } break; case AFB_SESSION_RENEW: if (AFB_SUCCESS != ctxTokenRefresh (clientCtx, request)) { request->errcode=MHD_HTTP_UNAUTHORIZED; json_object_object_add(jcall, "status", json_object_new_string ("fail")); json_object_object_add(jcall, "info", json_object_new_string ("AFB_SESSION_REFRESH Broken Exchange Token Chain")); json_object_object_add(request->jresp, "request", jcall); return (AFB_DONE); } else { json_object_object_add(jcall, "uuid", json_object_new_string (clientCtx->uuid)); json_object_object_add(jcall, "token", json_object_new_string (clientCtx->token)); json_object_object_add(jcall, "timeout", json_object_new_int (request->config->cntxTimeout)); } break; case AFB_SESSION_CLOSE: if (AFB_SUCCESS != ctxTokenCheck (clientCtx, request)) { request->errcode=MHD_HTTP_UNAUTHORIZED; json_object_object_add(jcall, "status", json_object_new_string ("empty")); json_object_object_add(jcall, "info", json_object_new_string ("AFB_SESSION_CLOSE Not a Valid Access Token")); json_object_object_add(request->jresp, "request", jcall); return (AFB_DONE); } else { json_object_object_add(jcall, "uuid", json_object_new_string (clientCtx->uuid)); } break; case AFB_SESSION_CHECK: default: // default action is check if (AFB_SUCCESS != ctxTokenCheck (clientCtx, request)) { request->errcode=MHD_HTTP_UNAUTHORIZED; json_object_object_add(jcall, "status", json_object_new_string ("fail")); json_object_object_add(jcall, "info", json_object_new_string ("AFB_SESSION_CHECK Invalid Active Token")); json_object_object_add(request->jresp, "request", jcall); return (AFB_DONE); } break; } } // Effectively call the API with a subset of the context jresp = plugin->apis[idx].callback(request, context); // handle intermediary Post Iterates out of band if ((jresp == NULL) && (request->errcode == MHD_HTTP_OK)) return (AFB_SUCCESS); // Session close is done after the API call so API can still use session in closing API if (AFB_SESSION_CLOSE == plugin->apis[idx].session) ctxTokenReset (clientCtx, request); // API should return NULL of a valid Json Object if (jresp == NULL) { json_object_object_add(jcall, "status", json_object_new_string ("null")); json_object_object_add(request->jresp, "request", jcall); request->errcode = MHD_HTTP_NO_RESPONSE; } else { json_object_object_add(jcall, "status", json_object_new_string ("processed")); json_object_object_add(request->jresp, "request", jcall); json_object_object_add(request->jresp, "response", jresp); } // cancel timeout and plugin signal handle before next call if (request->config->apiTimeout > 0) { alarm (0); for (sig=0; signals[sig] != 0; sig++) { signal (signals[sig], SIG_DFL); } } } return (AFB_DONE); } } return (AFB_FAIL); } STATIC AFB_error findAndCallApi (AFB_request *request, void *context) { int idx; AFB_error status; if (!request->api || !request->prefix) return (AFB_FAIL); // Search for a plugin with this urlpath for (idx = 0; request->plugins[idx] != NULL; idx++) { if (!strcmp(request->plugins[idx]->prefix, request->prefix)) { status =callPluginApi(request, idx, context); break; } } // No plugin was found if (request->plugins[idx] == NULL) { request->jresp = jsonNewMessage(AFB_FATAL, "No Plugin=[%s] Url=%s", request->prefix, request->url); goto ExitOnError; } // plugin callback did not return a valid Json Object if (status == AFB_FAIL) { request->jresp = jsonNewMessage(AFB_FATAL, "No API=[%s] for Plugin=[%s] url=[%s]", request->api, request->prefix, request->url); goto ExitOnError; } // Everything look OK return (status); ExitOnError: request->errcode = MHD_HTTP_UNPROCESSABLE_ENTITY; return (AFB_FAIL); } // This CB is call for every item with a form post it reformat iterator values // and callback Plugin API for each Item within PostForm. doPostIterate (void *cls, enum MHD_ValueKind kind, const char *key, const char *filename, const char *mimetype, const char *encoding, const char *data, uint64_t offset, size_t size) { AFB_error status; AFB_PostItem item; // retrieve API request from Post iterator handle AFB_PostHandle *postHandle = (AFB_PostHandle*)cls; AFB_request *request = (AFB_request*)postHandle->private; AFB_PostRequest postRequest; fprintf (stderr, "postHandle key=%s filename=%s len=%d mime=%s\n", key, filename, size, mimetype); // Create and Item value for Plugin API item.kind = kind; item.key = key; item.filename = filename; item.mimetype = mimetype; item.encoding = encoding; item.len = size; item.data = data; item.offset = offset; // Reformat Request to make it somehow similar to GET/PostJson case postRequest.data= (char*) postHandle; postRequest.len = size; postRequest.type= AFB_POST_FORM;; request->post = &postRequest; // effectively call plugin API status = findAndCallApi (request, &item); // when returning no processing of postform stop if (status != AFB_SUCCESS) return MHD_NO; // let's allow iterator to move to next item return (MHD_YES); } STATIC void freeRequest (AFB_request *request) { free (request->prefix); free (request->api); free (request); } STATIC AFB_request *createRequest (struct MHD_Connection *connection, AFB_session *session, const char* url) { AFB_request *request; int idx; // Start with a clean request request = calloc (1, sizeof (AFB_request)); char *urlcpy1, *urlcpy2; char *baseapi, *baseurl; // Extract plugin urlpath from request and make two copy because strsep overload copy urlcpy1 = urlcpy2 = strdup(url); baseurl = strsep(&urlcpy2, "/"); if (baseurl == NULL) { request->jresp = jsonNewMessage(AFB_FATAL, "Invalid API call url=[%s]", url); request->errcode = MHD_HTTP_BAD_REQUEST; goto Done; } // let's compute URL and call API baseapi = strsep(&urlcpy2, "/"); if (baseapi == NULL) { request->jresp = jsonNewMessage(AFB_FATAL, "Invalid API call plugin=[%s] url=[%s]", baseurl, url); request->errcode = MHD_HTTP_BAD_REQUEST; goto Done; } // build request structure request->connection = connection; request->config = session->config; request->url = url; request->prefix = strdup (baseurl); request->api = strdup (baseapi); request->plugins= session->plugins; for (idx = 0; idx < session->config->pluginCount; idx++) { if (!strcmp(baseurl, session->plugins[idx]->prefix)) { request->plugin = session->plugins[idx]; break; } } Done: free(urlcpy1); return (request); } // process rest API query PUBLIC int doRestApi(struct MHD_Connection *connection, AFB_session *session, const char* url, const char *method , const char *upload_data, size_t *upload_data_size, void **con_cls) { static int postcount = 0; // static counter to debug POST protocol json_object *errMessage; AFB_error status; struct MHD_Response *webResponse; const char *serialized; AFB_request *request; AFB_PostHandle *postHandle; AFB_PostRequest postRequest; int ret; // if post data may come in multiple calls if (0 == strcmp(method, MHD_HTTP_METHOD_POST)) { const char *encoding, *param; int contentlen = -1; postHandle = *con_cls; // This is the initial post event let's create form post structure POST datas come in multiple events if (postHandle == NULL) { // allocate application POST processor handle to zero postHandle = calloc(1, sizeof (AFB_PostHandle)); postHandle->uid = postcount++; // build a UID for DEBUG *con_cls = postHandle; // update context with posthandle // Let make sure we have the right encoding and a valid length encoding = MHD_lookup_connection_value(connection, MHD_HEADER_KIND, MHD_HTTP_HEADER_CONTENT_TYPE); // We are facing an empty post let's process it as a get if (encoding == NULL) { request= createRequest (connection, session, url); goto ProcessApiCall; } // Form post is handle through a PostProcessor and call API once per form key if (strcasestr(encoding, FORM_CONTENT) != NULL) { if (verbose) fprintf(stderr, "Create PostForm[uid=%d]\n", postHandle->uid); request = createRequest (connection, session, url); if (request->jresp != NULL) goto ProcessApiCall; postHandle = malloc(sizeof (AFB_PostHandle)); // allocate application POST processor handle postHandle->type = AFB_POST_FORM; postHandle->pp = MHD_create_post_processor (connection, MAX_POST_SIZE, doPostIterate, postHandle); postHandle->private= (void*)request; if (NULL == postHandle->pp) { fprintf(stderr,"OOPS: Internal error fail to allocate MHD_create_post_processor\n"); free (postHandle); return MHD_NO; } return MHD_YES; } // POST json is store into a buffer and present in one piece to API if (strcasestr(encoding, JSON_CONTENT) != NULL) { param = MHD_lookup_connection_value(connection, MHD_HEADER_KIND, MHD_HTTP_HEADER_CONTENT_LENGTH); if (param) sscanf(param, "%i", &contentlen); // Because PostJson are build in RAM size is constrained if (contentlen > MAX_POST_SIZE) { errMessage = jsonNewMessage(AFB_FATAL, "Post Date to big %d > %d", contentlen, MAX_POST_SIZE); goto ExitOnError; } // Size is OK, let's allocate a buffer to hold post data postHandle->type = AFB_POST_JSON; postHandle->private = malloc(contentlen + 1); // allocate memory for full POST data + 1 for '\0' enf of string // if (verbose) fprintf(stderr, "Create PostJson[uid=%d] Size=%d\n", postHandle->uid, contentlen); return MHD_YES; } else { // We only support Json and Form Post format errMessage = jsonNewMessage(AFB_FATAL, "Post Date wrong type encoding=%s != %s", encoding, JSON_CONTENT); goto ExitOnError; } } // This time we receive partial/all Post data. Note that even if we get all POST data. We should nevertheless // return MHD_YES and not process the request directly. Otherwise Libmicrohttpd is unhappy and fails with // 'Internal application error, closing connection'. if (*upload_data_size) { if (postHandle->type == AFB_POST_FORM) { // if (verbose) fprintf(stderr, "Processing PostForm[uid=%d]\n", postHandle->uid); MHD_post_process (postHandle->pp, upload_data, *upload_data_size); } // Process JsonPost request when buffer is completed let's call API if (postHandle->type == AFB_POST_JSON) { // if (verbose) fprintf(stderr, "Updating PostJson[uid=%d]\n", postHandle->uid); memcpy(&postHandle->private[postHandle->len], upload_data, *upload_data_size); postHandle->len = postHandle->len + *upload_data_size; } *upload_data_size = 0; return MHD_YES; } else { // we have finish with Post reception let's finish the work // Create a request structure to finalise the request request= createRequest (connection, session, url); if (request->jresp != NULL) { errMessage = request->jresp; goto ExitOnError; } // Postform add application context handle to request if (postHandle->type == AFB_POST_FORM) { postRequest.data = (char*) postHandle; postRequest.type = postHandle->type; request->post = &postRequest; } if (postHandle->type == AFB_POST_JSON) { // if (verbose) fprintf(stderr, "Processing PostJson[uid=%d]\n", postHandle->uid); param = MHD_lookup_connection_value(connection, MHD_HEADER_KIND, MHD_HTTP_HEADER_CONTENT_LENGTH); if (param) sscanf(param, "%i", &contentlen); // At this level we're may verify that we got everything and process DATA if (postHandle->len != contentlen) { errMessage = jsonNewMessage(AFB_FATAL, "Post Data Incomplete UID=%d Len %d != %d", postHandle->uid, contentlen, postHandle->len); goto ExitOnError; } // Before processing data, make sure buffer string is properly ended postHandle->private[postHandle->len] = '\0'; postRequest.data = postHandle->private; postRequest.type = postHandle->type; request->post = &postRequest; // if (verbose) fprintf(stderr, "Close Post[%d] Buffer=%s\n", postHandle->uid, request->post->data); } } } else { // this is a get we only need a request request= createRequest (connection, session, url); }; ProcessApiCall: // Request is ready let's call API without any extra handle status = findAndCallApi (request, NULL); serialized = json_object_to_json_string(request->jresp); webResponse = MHD_create_response_from_buffer(strlen(serialized), (void*) serialized, MHD_RESPMEM_MUST_COPY); // client did not pass token on URI let's use cookies if ((!request->restfull) && (request->context != NULL)) { char cookie[64]; snprintf (cookie, sizeof (cookie), "%s=%s", COOKIE_NAME, request->uuid); MHD_add_response_header (webResponse, MHD_HTTP_HEADER_SET_COOKIE, cookie); } // if requested add an error status if (request->errcode != 0) ret=MHD_queue_response (connection, request->errcode, webResponse); else MHD_queue_response(connection, MHD_HTTP_OK, webResponse); MHD_destroy_response(webResponse); json_object_put(request->jresp); // decrease reference rqtcount to free the json object freeRequest (request); return MHD_YES; ExitOnError: freeRequest (request); serialized = json_object_to_json_string(errMessage); webResponse = MHD_create_response_from_buffer(strlen(serialized), (void*) serialized, MHD_RESPMEM_MUST_COPY); MHD_queue_response(connection, MHD_HTTP_BAD_REQUEST, webResponse); MHD_destroy_response(webResponse); json_object_put(errMessage); // decrease reference rqtcount to free the json object return MHD_YES; } // Loop on plugins. Check that they have the right type, prepare a JSON object with prefix STATIC AFB_plugin ** RegisterJsonPlugins(AFB_plugin **plugins) { int idx, jdx; for (idx = 0; plugins[idx] != NULL; idx++) { if (plugins[idx]->type != AFB_PLUGIN_JSON) { fprintf(stderr, "ERROR: AFSV plugin[%d] invalid type=%d != %d\n", idx, AFB_PLUGIN_JSON, plugins[idx]->type); } else { // some sanity controls if ((plugins[idx]->prefix == NULL) || (plugins[idx]->info == NULL) || (plugins[idx]->apis == NULL)) { if (plugins[idx]->prefix == NULL) plugins[idx]->prefix = "No URL prefix for APIs"; if (plugins[idx]->info == NULL) plugins[idx]->info = "No Info describing plugin APIs"; fprintf(stderr, "ERROR: plugin[%d] invalid prefix=%s info=%s", idx, plugins[idx]->prefix, plugins[idx]->info); return NULL; } if (verbose) fprintf(stderr, "Loading plugin[%d] prefix=[%s] info=%s\n", idx, plugins[idx]->prefix, plugins[idx]->info); // Prebuild plugin jtype to boost API response plugins[idx]->jtype = json_object_new_string(plugins[idx]->prefix); json_object_get(plugins[idx]->jtype); // increase reference count to make it permanent plugins[idx]->prefixlen = strlen(plugins[idx]->prefix); // Prebuild each API jtype to boost API json response for (jdx = 0; plugins[idx]->apis[jdx].name != NULL; jdx++) { AFB_privateApi *private = malloc (sizeof (AFB_privateApi)); if (plugins[idx]->apis[jdx].private != NULL) { fprintf (stderr, "WARNING: plugin=%s api=%s private handle should be NULL=0x%x\n" ,plugins[idx]->prefix,plugins[idx]->apis[jdx].name, plugins[idx]->apis[jdx].private); } private->len = strlen (plugins[idx]->apis[jdx].name); private->jtype=json_object_new_string(plugins[idx]->apis[jdx].name); json_object_get(private->jtype); // increase reference count to make it permanent plugins[idx]->apis[jdx].private = private; } } } return (plugins); } STATIC void scanDirectory(char *dirpath, int dirfd, AFB_plugin **plugins, int *count) { DIR *dir; void *libso; struct dirent *pluginDir; AFB_plugin* (*pluginRegisterFct)(void); char pluginPath[255]; // Open Directory to scan over it dir = fdopendir (dirfd); if (dir == NULL) { fprintf(stderr, "ERROR in scanning directory\n"); return; } if (verbose) fprintf (stderr, "Scanning dir=[%s] for plugins\n", dirpath); while ((pluginDir = readdir(dir)) != NULL) { // Loop on any contained directory if ((pluginDir->d_type == DT_DIR) && (pluginDir->d_name[0] != '.')) { int fd = openat (dirfd, pluginDir->d_name, O_DIRECTORY); char newpath[255]; strncpy (newpath, dirpath, sizeof(newpath)); strncat (newpath, "/", sizeof(newpath)); strncat (newpath, pluginDir->d_name, sizeof(newpath)); scanDirectory (newpath, fd, plugins, count); close (fd); } else { // This is a file but not a plugin let's move to next directory element if (!strstr (pluginDir->d_name, ".so")) continue; // This is a loadable library let's check if it's a plugin snprintf (pluginPath, sizeof(pluginPath), "%s/%s", dirpath, pluginDir->d_name); libso = dlopen (pluginPath, RTLD_NOW | RTLD_LOCAL); // Load fail we ignore this .so file if (!libso) { fprintf(stderr, "[%s] is not loadable, continuing...\n", pluginDir->d_name); continue; } pluginRegisterFct = dlsym (libso, "pluginRegister"); free (libso); if (!pluginRegisterFct) { fprintf(stderr, "[%s] is not an AFB plugin, continuing...\n", pluginDir->d_name); continue; } // if max plugin is reached let's stop searching if (*count == AFB_MAX_PLUGINS) { fprintf(stderr, "[%s] is not loaded [Max Count=%d reached]\n", *count); continue; } if (verbose) fprintf(stderr, "[%s] is a valid AFB plugin, loading pos[%d]\n", pluginDir->d_name, *count); plugins[*count] = (AFB_plugin *) malloc (sizeof(AFB_plugin)); plugins[*count] = (**pluginRegisterFct)(); *count = *count +1; } } closedir (dir); } void initPlugins(AFB_session *session) { static AFB_plugin **plugins; afbJsonType = json_object_new_string (AFB_MSG_JTYPE); int count = 0; char *dirpath; int dirfd; /* pre-allocate for AFB_MAX_PLUGINS plugins, we will downsize later */ plugins = (AFB_plugin **) malloc (AFB_MAX_PLUGINS *sizeof(AFB_plugin)); // Loop on every directory passed in --plugins=xxx while (dirpath = strsep(&session->config->ldpaths, ":")) { // Ignore any directory we fail to open if ((dirfd = open(dirpath, O_DIRECTORY)) <= 0) { fprintf(stderr, "Invalid directory path=[%s]\n", dirpath); continue; } scanDirectory (dirpath, dirfd, plugins, &count); close (dirfd); } if (count == 0) { fprintf(stderr, "No plugins found, afb-daemon is unlikely to work in this configuration, exiting...\n"); exit (-1); } // downsize structure to effective number of loaded plugins plugins = (AFB_plugin **)realloc (plugins, (count+1)*sizeof(AFB_plugin)); plugins[count] = NULL; // complete plugins and save them within current sessions session->plugins = RegisterJsonPlugins(plugins); session->config->pluginCount = count; }