src/afb-api-ws.c

   1 /*
   2  * Copyright (C) 2015, 2016, 2017 "IoT.bzh"
   3  * Author José Bollo <jose.bollo@iot.bzh>
   4  *
   5  * Licensed under the Apache License, Version 2.0 (the "License");
   6  * you may not use this file except in compliance with the License.
   7  * You may obtain a copy of the License at
   8  *
   9  *   http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing, software
  12  * distributed under the License is distributed on an "AS IS" BASIS,
  13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  * See the License for the specific language governing permissions and
  15  * limitations under the License.
  16  */
  17
  18 #define _GNU_SOURCE
  19 #define NO_PLUGIN_VERBOSE_MACRO
  20
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <assert.h>
  24 #include <fcntl.h>
  25 #include <unistd.h>
  26 #include <errno.h>
  27 #include <endian.h>
  28 #include <netdb.h>
  29 #include <sys/types.h>
  30 #include <sys/socket.h>
  31 #include <sys/un.h>
  32
  33 #include <json-c/json.h>
  34 #include <systemd/sd-event.h>
  35
  36 #include <afb/afb-req-itf.h>
  37
  38 #include "afb-common.h"
  39
  40 #include "afb-session.h"
  41 #include "afb-cred.h"
  42 #include "afb-ws.h"
  43 #include "afb-msg-json.h"
  44 #include "afb-apis.h"
  45 #include "afb-api-so.h"
  46 #include "afb-context.h"
  47 #include "afb-evt.h"
  48 #include "afb-xreq.h"
  49 #include "verbose.h"
  50 #include "sd-fds.h"
  51
  52 struct api_ws_memo;
  53 struct api_ws_event;
  54 struct api_ws_client;
  55
  56
  57
  58 /*
  59  */
  60 struct api_ws
  61 {
  62         char *path;             /* path of the object for the API */
  63         char *api;              /* api name of the interface */
  64         int fd;                 /* file descriptor */
  65         union {
  66                 struct {
  67                         uint32_t id;
  68                         struct afb_ws *ws;
  69                         struct api_ws_event *events;
  70                         struct api_ws_memo *memos;
  71                 } client;
  72                 struct {
  73                         sd_event_source *listensrc;
  74                         struct afb_evt_listener *listener; /* listener for broadcasted events */
  75                 } server;
  76         };
  77 };
  78
  79 #define RETOK   1
  80 #define RETERR  2
  81 #define RETRAW  3
  82
  83 /******************* websocket interface for client part **********************************/
  84
  85 static void api_ws_client_on_binary(void *closure, char *data, size_t size);
  86
  87 static const struct afb_ws_itf api_ws_client_ws_itf =
  88 {
  89         .on_close = NULL,
  90         .on_text = NULL,
  91         .on_binary = api_ws_client_on_binary,
  92         .on_error = NULL,
  93         .on_hangup = NULL
  94 };
  95
  96 /******************* event structures for server part **********************************/
  97
  98 static void api_ws_server_event_add(void *closure, const char *event, int eventid);
  99 static void api_ws_server_event_remove(void *closure, const char *event, int eventid);
 100 static void api_ws_server_event_push(void *closure, const char *event, int eventid, struct json_object *object);
 101 static void api_ws_server_event_broadcast(void *closure, const char *event, int eventid, struct json_object *object);
 102
 103 /* the interface for events pushing */
 104 static const struct afb_evt_itf api_ws_server_evt_itf = {
 105         .broadcast = api_ws_server_event_broadcast,
 106         .push = api_ws_server_event_push,
 107         .add = api_ws_server_event_add,
 108         .remove = api_ws_server_event_remove
 109 };
 110
 111 /******************* client description part for server *****************************/
 112
 113 struct api_ws_client
 114 {
 115         /* the server ws-api */
 116         const char *api;
 117
 118         /* count of references */
 119         int refcount;
 120
 121         /* listener for events */
 122         struct afb_evt_listener *listener;
 123
 124         /* file descriptor */
 125         int fd;
 126
 127         /* websocket */
 128         struct afb_ws *ws;
 129
 130         /* credentials */
 131         struct afb_cred *cred;
 132 };
 133
 134 /******************* websocket interface for client part **********************************/
 135
 136 static void api_ws_server_on_binary(void *closure, char *data, size_t size);
 137 static void api_ws_server_on_hangup(void *closure);
 138
 139 static const struct afb_ws_itf api_ws_server_ws_itf =
 140 {
 141         .on_close = NULL,
 142         .on_text = NULL,
 143         .on_binary = api_ws_server_on_binary,
 144         .on_error = NULL,
 145         .on_hangup = api_ws_server_on_hangup
 146 };
 147
 148 /******************* ws request part for server *****************/
 149
 150 /*
 151  * structure for a ws request
 152  */
 153 struct api_ws_server_req {
 154         struct afb_xreq xreq;           /* the xreq */
 155         struct api_ws_client *client;   /* the client of the request */
 156         char *rcvdata;                  /* the received data to free */
 157         const char *request;            /* the readen request as string */
 158         size_t lenreq;                  /* the length of the request */
 159         uint32_t msgid;                 /* the incoming request msgid */
 160 };
 161
 162 static void api_ws_server_req_success_cb(struct afb_xreq *xreq, struct json_object *obj, const char *info);
 163 static void api_ws_server_req_fail_cb(struct afb_xreq *xreq, const char *status, const char *info);
 164 static void api_ws_server_req_destroy_cb(struct afb_xreq *xreq);
 165 static int api_ws_server_req_subscribe_cb(struct afb_xreq *xreq, struct afb_event event);
 166 static int api_ws_server_req_unsubscribe_cb(struct afb_xreq *xreq, struct afb_event event);
 167
 168 const struct afb_xreq_query_itf afb_api_ws_xreq_itf = {
 169         .success = api_ws_server_req_success_cb,
 170         .fail = api_ws_server_req_fail_cb,
 171         .unref = api_ws_server_req_destroy_cb,
 172         .subscribe = api_ws_server_req_subscribe_cb,
 173         .unsubscribe = api_ws_server_req_unsubscribe_cb
 174 };
 175
 176 /******************* common part **********************************/
 177
 178 /*
 179  * create a structure api_ws not connected to the 'path'.
 180  */
 181 static struct api_ws *api_ws_make(const char *path)
 182 {
 183         struct api_ws *api;
 184         size_t length;
 185
 186         /* allocates the structure */
 187         length = strlen(path);
 188         api = calloc(1, sizeof *api + 1 + length);
 189         if (api == NULL) {
 190                 errno = ENOMEM;
 191                 goto error;
 192         }
 193
 194         /* path is copied after the struct */
 195         api->path = (char*)(api+1);
 196         memcpy(api->path, path, length + 1);
 197
 198         /* api name is at the end of the path */
 199         while (length && path[length - 1] != '/' && path[length - 1] != ':')
 200                 length = length - 1;
 201         api->api = &api->path[length];
 202         if (api->api == NULL || !afb_apis_is_valid_api_name(api->api)) {
 203                 errno = EINVAL;
 204                 goto error2;
 205         }
 206
 207         api->fd = -1;
 208         return api;
 209
 210 error2:
 211         free(api);
 212 error:
 213         return NULL;
 214 }
 215
 216 static int api_ws_socket_unix(const char *path, int server)
 217 {
 218         int fd, rc;
 219         struct sockaddr_un addr;
 220         size_t length;
 221
 222         length = strlen(path);
 223         if (length >= 108) {
 224                 errno = ENAMETOOLONG;
 225                 return -1;
 226         }
 227
 228         if (server)
 229                 unlink(path);
 230
 231         fd = socket(AF_UNIX, SOCK_STREAM, 0);
 232         if (fd < 0)
 233                 return fd;
 234
 235         memset(&addr, 0, sizeof addr);
 236         addr.sun_family = AF_UNIX;
 237         strcpy(addr.sun_path, path);
 238         if (server) {
 239                 rc = bind(fd, (struct sockaddr *) &addr, (socklen_t)(sizeof addr));
 240         } else {
 241                 rc = connect(fd, (struct sockaddr *) &addr, (socklen_t)(sizeof addr));
 242         }
 243         if (rc < 0) {
 244                 close(fd);
 245                 return rc;
 246         }
 247         return fd;
 248 }
 249
 250 static int api_ws_socket_inet(const char *path, int server)
 251 {
 252         int rc, fd;
 253         const char *service, *host, *api;
 254         struct addrinfo hint, *rai, *iai;
 255
 256         /* scan the uri */
 257         api = strrchr(path, '/');
 258         service = strrchr(path, ':');
 259         if (api == NULL || service == NULL || api < service) {
 260                 errno = EINVAL;
 261                 return -1;
 262         }
 263         host = strndupa(path, service++ - path);
 264         service = strndupa(service, api - service);
 265
 266         /* get addr */
 267         memset(&hint, 0, sizeof hint);
 268         hint.ai_family = AF_INET;
 269         hint.ai_socktype = SOCK_STREAM;
 270         rc = getaddrinfo(host, service, &hint, &rai);
 271         if (rc != 0) {
 272                 errno = EINVAL;
 273                 return -1;
 274         }
 275
 276         /* get the socket */
 277         iai = rai;
 278         while (iai != NULL) {
 279                 fd = socket(iai->ai_family, iai->ai_socktype, iai->ai_protocol);
 280                 if (fd >= 0) {
 281                         if (server) {
 282                                 rc = bind(fd, iai->ai_addr, iai->ai_addrlen);
 283                         } else {
 284                                 rc = connect(fd, iai->ai_addr, iai->ai_addrlen);
 285                         }
 286                         if (rc == 0) {
 287                                 freeaddrinfo(rai);
 288                                 return fd;
 289                         }
 290                         close(fd);
 291                 }
 292                 iai = iai->ai_next;
 293         }
 294         freeaddrinfo(rai);
 295         return -1;
 296
 297 }
 298
 299 static int api_ws_socket(const char *path, int server)
 300 {
 301         int fd, rc;
 302
 303         /* check for systemd socket */
 304         if (0 == strncmp(path, "sd:", 3))
 305                 fd = sd_fds_for(path + 3);
 306         else {
 307                 /* check for unix socket */
 308                 if (0 == strncmp(path, "unix:", 5))
 309                         /* unix socket */
 310                         fd = api_ws_socket_unix(path + 5, server);
 311                 else
 312                         /* inet socket */
 313                         fd = api_ws_socket_inet(path, server);
 314
 315                 if (fd >= 0 && server) {
 316                         rc = 1;
 317                         setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &rc, sizeof rc);
 318                         rc = listen(fd, 5);
 319                 }
 320         }
 321         /* configure the socket */
 322         if (fd >= 0) {
 323                 fcntl(fd, F_SETFD, FD_CLOEXEC);
 324                 fcntl(fd, F_SETFL, O_NONBLOCK);
 325         }
 326         return fd;
 327 }
 328
 329 /******************* serialisation part **********************************/
 330
 331 struct readbuf
 332 {
 333         char *head, *end;
 334 };
 335
 336 #define WRITEBUF_COUNT_MAX  32
 337 struct writebuf
 338 {
 339         struct iovec iovec[WRITEBUF_COUNT_MAX];
 340         uint32_t uints[WRITEBUF_COUNT_MAX];
 341         int count;
 342 };
 343
 344 static char *api_ws_read_get(struct readbuf *rb, uint32_t length)
 345 {
 346         char *before = rb->head;
 347         char *after = before + length;
 348         if (after > rb->end)
 349                 return 0;
 350         rb->head = after;
 351         return before;
 352 }
 353
 354 static int api_ws_read_uint32(struct readbuf *rb, uint32_t *value)
 355 {
 356         char *after = rb->head + sizeof *value;
 357         if (after > rb->end)
 358                 return 0;
 359         memcpy(value, rb->head, sizeof *value);
 360         rb->head = after;
 361         *value = le32toh(*value);
 362         return 1;
 363 }
 364
 365 static int api_ws_read_string(struct readbuf *rb, const char **value, size_t *length)
 366 {
 367         uint32_t len;
 368         if (!api_ws_read_uint32(rb, &len) || !len)
 369                 return 0;
 370         if (length)
 371                 *length = (size_t)(len - 1);
 372         return (*value = api_ws_read_get(rb, len)) != NULL &&  rb->head[-1] == 0;
 373 }
 374
 375 static int api_ws_read_object(struct readbuf *rb, struct json_object **object)
 376 {
 377         size_t length;
 378         const char *string;
 379         return api_ws_read_string(rb, &string, &length) && ((*object = json_tokener_parse(string)) != NULL) == (strcmp(string, "null") != 0);
 380 }
 381
 382 static int api_ws_write_put(struct writebuf *wb, const void *value, size_t length)
 383 {
 384         int i = wb->count;
 385         if (i == WRITEBUF_COUNT_MAX)
 386                 return 0;
 387         wb->iovec[i].iov_base = (void*)value;
 388         wb->iovec[i].iov_len = length;
 389         wb->count = i + 1;
 390         return 1;
 391 }
 392
 393 static int api_ws_write_char(struct writebuf *wb, char value)
 394 {
 395         int i = wb->count;
 396         if (i == WRITEBUF_COUNT_MAX)
 397                 return 0;
 398         *(char*)&wb->uints[i] = value;
 399         wb->iovec[i].iov_base = &wb->uints[i];
 400         wb->iovec[i].iov_len = 1;
 401         wb->count = i + 1;
 402         return 1;
 403 }
 404
 405 static int api_ws_write_uint32(struct writebuf *wb, uint32_t value)
 406 {
 407         int i = wb->count;
 408         if (i == WRITEBUF_COUNT_MAX)
 409                 return 0;
 410         wb->uints[i] = htole32(value);
 411         wb->iovec[i].iov_base = &wb->uints[i];
 412         wb->iovec[i].iov_len = sizeof wb->uints[i];
 413         wb->count = i + 1;
 414         return 1;
 415 }
 416
 417 static int api_ws_write_string_length(struct writebuf *wb, const char *value, size_t length)
 418 {
 419         uint32_t len = (uint32_t)++length;
 420         return (size_t)len == length && len && api_ws_write_uint32(wb, len) && api_ws_write_put(wb, value, length);
 421 }
 422
 423 static int api_ws_write_string(struct writebuf *wb, const char *value)
 424 {
 425         return api_ws_write_string_length(wb, value, strlen(value));
 426 }
 427
 428 static int api_ws_write_object(struct writebuf *wb, struct json_object *object)
 429 {
 430         const char *string = json_object_to_json_string_ext(object, JSON_C_TO_STRING_PLAIN);
 431         return string != NULL && api_ws_write_string(wb, string);
 432 }
 433
 434
 435
 436
 437 /******************* client part **********************************/
 438
 439 /*
 440  * structure for recording query data
 441  */
 442 struct api_ws_memo {
 443         struct api_ws_memo *next;               /* the next memo */
 444         struct api_ws *api;             /* the ws api */
 445         struct afb_xreq *xreq;          /* the request handle */
 446 #if 0
 447         struct afb_req req;             /* the request handle */
 448         struct afb_context *context;    /* the context of the query */
 449 #endif
 450         uint32_t msgid;                 /* the message identifier */
 451 };
 452
 453 struct api_ws_event
 454 {
 455         struct api_ws_event *next;
 456         struct afb_event event;
 457         int eventid;
 458         int refcount;
 459 };
 460
 461 /* search a memorized request */
 462 static struct api_ws_memo *api_ws_client_memo_search(struct api_ws *api, uint32_t msgid)
 463 {
 464         struct api_ws_memo *memo;
 465
 466         memo = api->client.memos;
 467         while (memo != NULL && memo->msgid != msgid)
 468                 memo = memo->next;
 469
 470         return memo;
 471 }
 472
 473 /* search the event */
 474 static struct api_ws_event *api_ws_client_event_search(struct api_ws *api, uint32_t eventid, const char *name)
 475 {
 476         struct api_ws_event *ev;
 477
 478         ev = api->client.events;
 479         while (ev != NULL && (ev->eventid != eventid || 0 != strcmp(afb_evt_event_name(ev->event), name)))
 480                 ev = ev->next;
 481
 482         return ev;
 483 }
 484
 485
 486 /* allocates and init the memorizing data */
 487 static struct api_ws_memo *api_ws_client_memo_make(struct api_ws *api, struct afb_xreq *xreq)
 488 {
 489         struct api_ws_memo *memo;
 490
 491         memo = malloc(sizeof *memo);
 492         if (memo != NULL) {
 493                 afb_xreq_addref(xreq);
 494                 memo->xreq = xreq;
 495                 do { memo->msgid = ++api->client.id; } while(api_ws_client_memo_search(api, memo->msgid) != NULL);
 496                 memo->api = api;
 497                 memo->next = api->client.memos;
 498                 api->client.memos = memo;
 499         }
 500         return memo;
 501 }
 502
 503 /* free and release the memorizing data */
 504 static void api_ws_client_memo_destroy(struct api_ws_memo *memo)
 505 {
 506         struct api_ws_memo **prv;
 507
 508         prv = &memo->api->client.memos;
 509         while (*prv != NULL) {
 510                 if (*prv == memo) {
 511                         *prv = memo->next;
 512                         break;
 513                 }
 514                 prv = &(*prv)->next;
 515         }
 516
 517         afb_xreq_unref(memo->xreq);
 518         free(memo);
 519 }
 520
 521 /* get event data from the message */
 522 static int api_ws_client_msg_event_read(struct readbuf *rb, uint32_t *eventid, const char **name)
 523 {
 524         return api_ws_read_uint32(rb, eventid) && api_ws_read_string(rb, name, NULL);
 525 }
 526
 527 /* get event from the message */
 528 static int api_ws_client_msg_event_get(struct api_ws *api, struct readbuf *rb, struct api_ws_event **ev)
 529 {
 530         const char *name;
 531         uint32_t eventid;
 532
 533         /* get event data from the message */
 534         if (!api_ws_client_msg_event_read(rb, &eventid, &name)) {
 535                 ERROR("Invalid message");
 536                 return 0;
 537         }
 538
 539         /* check conflicts */
 540         *ev = api_ws_client_event_search(api, eventid, name);
 541         if (*ev == NULL) {
 542                 ERROR("event %s not found", name);
 543                 return 0;
 544         }
 545
 546         return 1;
 547 }
 548
 549 /* get event from the message */
 550 static int api_ws_client_msg_memo_get(struct api_ws *api, struct readbuf *rb, struct api_ws_memo **memo)
 551 {
 552         uint32_t msgid;
 553
 554         /* get event data from the message */
 555         if (!api_ws_read_uint32(rb, &msgid)) {
 556                 ERROR("Invalid message");
 557                 return 0;
 558         }
 559
 560         /* get the memo */
 561         *memo = api_ws_client_memo_search(api, msgid);
 562         if (*memo == NULL) {
 563                 ERROR("message not found");
 564                 return 0;
 565         }
 566
 567         return 1;
 568 }
 569
 570 /* read a subscrition message */
 571 static int api_ws_client_msg_subscription_get(struct api_ws *api, struct readbuf *rb, struct api_ws_event **ev, struct api_ws_memo **memo)
 572 {
 573         return api_ws_client_msg_memo_get(api, rb, memo) && api_ws_client_msg_event_get(api, rb, ev);
 574 }
 575
 576 /* adds an event */
 577 static void api_ws_client_event_create(struct api_ws *api, struct readbuf *rb)
 578 {
 579         size_t offset;
 580         const char *name;
 581         uint32_t eventid;
 582         struct api_ws_event *ev;
 583
 584         /* get event data from the message */
 585         offset = api_ws_client_msg_event_read(rb, &eventid, &name);
 586         if (offset == 0) {
 587                 ERROR("Invalid message");
 588                 return;
 589         }
 590
 591         /* check conflicts */
 592         ev = api_ws_client_event_search(api, eventid, name);
 593         if (ev != NULL) {
 594                 ev->refcount++;
 595                 return;
 596         }
 597
 598         /* no conflict, try to add it */
 599         ev = malloc(sizeof *ev);
 600         if (ev != NULL) {
 601                 ev->event = afb_evt_create_event(name);
 602                 if (ev->event.closure == NULL)
 603                         free(ev);
 604                 else {
 605                         ev->refcount = 1;
 606                         ev->eventid = eventid;
 607                         ev->next = api->client.events;
 608                         api->client.events = ev;
 609                         return;
 610                 }
 611         }
 612         ERROR("can't create event %s, out of memory", name);
 613 }
 614
 615 /* removes an event */
 616 static void api_ws_client_event_drop(struct api_ws *api, struct readbuf *rb)
 617 {
 618         struct api_ws_event *ev, **prv;
 619
 620         /* retrieves the event */
 621         if (!api_ws_client_msg_event_get(api, rb, &ev))
 622                 return;
 623
 624         /* decrease the reference count */
 625         if (--ev->refcount)
 626                 return;
 627
 628         /* unlinks the event */
 629         prv = &api->client.events;
 630         while (*prv != ev)
 631                 prv = &(*prv)->next;
 632         *prv = ev->next;
 633
 634         /* destroys the event */
 635         afb_event_drop(ev->event);
 636         free(ev);
 637 }
 638
 639 /* subscribes an event */
 640 static void api_ws_client_event_subscribe(struct api_ws *api, struct readbuf *rb)
 641 {
 642         struct api_ws_event *ev;
 643         struct api_ws_memo *memo;
 644
 645         if (api_ws_client_msg_subscription_get(api, rb, &ev, &memo)) {
 646                 /* subscribe the request from the event */
 647                 if (afb_xreq_subscribe(memo->xreq, ev->event) < 0)
 648                         ERROR("can't subscribe: %m");
 649         }
 650 }
 651
 652 /* unsubscribes an event */
 653 static void api_ws_client_event_unsubscribe(struct api_ws *api, struct readbuf *rb)
 654 {
 655         struct api_ws_event *ev;
 656         struct api_ws_memo *memo;
 657
 658         if (api_ws_client_msg_subscription_get(api, rb, &ev, &memo)) {
 659                 /* unsubscribe the request from the event */
 660                 if (afb_xreq_unsubscribe(memo->xreq, ev->event) < 0)
 661                         ERROR("can't unsubscribe: %m");
 662         }
 663 }
 664
 665 /* receives broadcasted events */
 666 static void api_ws_client_event_broadcast(struct api_ws *api, struct readbuf *rb)
 667 {
 668         struct json_object *object;
 669         const char *event;
 670
 671         if (api_ws_read_string(rb, &event, NULL) && api_ws_read_object(rb, &object))
 672                 afb_evt_broadcast(event, object);
 673         else
 674                 ERROR("unreadable broadcasted event");
 675 }
 676
 677 /* pushs an event */
 678 static void api_ws_client_event_push(struct api_ws *api, struct readbuf *rb)
 679 {
 680         struct api_ws_event *ev;
 681         struct json_object *object;
 682
 683         if (api_ws_client_msg_event_get(api, rb, &ev) && api_ws_read_object(rb, &object))
 684                 afb_event_push(ev->event, object);
 685         else
 686                 ERROR("unreadable push event");
 687 }
 688
 689 static void api_ws_client_reply_success(struct api_ws *api, struct readbuf *rb)
 690 {
 691         struct api_ws_memo *memo;
 692         struct json_object *object;
 693         const char *info;
 694         uint32_t flags;
 695
 696         /* retrieve the message data */
 697         if (!api_ws_client_msg_memo_get(api, rb, &memo))
 698                 return;
 699
 700         if (api_ws_read_uint32(rb, &flags)
 701          && api_ws_read_string(rb, &info, NULL)
 702          && api_ws_read_object(rb, &object)) {
 703                 memo->xreq->context.flags = (unsigned)flags;
 704                 afb_xreq_success(memo->xreq, object, *info ? info : NULL);
 705         } else {
 706                 /* failing to have the answer */
 707                 afb_xreq_fail(memo->xreq, "error", "ws error");
 708         }
 709         api_ws_client_memo_destroy(memo);
 710 }
 711
 712 static void api_ws_client_reply_fail(struct api_ws *api, struct readbuf *rb)
 713 {
 714         struct api_ws_memo *memo;
 715         const char *info, *status;
 716         uint32_t flags;
 717
 718         /* retrieve the message data */
 719         if (!api_ws_client_msg_memo_get(api, rb, &memo))
 720                 return;
 721
 722         if (api_ws_read_uint32(rb, &flags)
 723          && api_ws_read_string(rb, &status, NULL)
 724          && api_ws_read_string(rb, &info, NULL)) {
 725                 memo->xreq->context.flags = (unsigned)flags;
 726                 afb_xreq_fail(memo->xreq, status, *info ? info : NULL);
 727         } else {
 728                 /* failing to have the answer */
 729                 afb_xreq_fail(memo->xreq, "error", "ws error");
 730         }
 731         api_ws_client_memo_destroy(memo);
 732 }
 733
 734 /* callback when receiving binary data */
 735 static void api_ws_client_on_binary(void *closure, char *data, size_t size)
 736 {
 737         if (size > 0) {
 738                 struct readbuf rb = { .head = data, .end = data + size };
 739                 switch (*rb.head++) {
 740                 case 'T': /* success */
 741                         api_ws_client_reply_success(closure, &rb);
 742                         break;
 743                 case 'F': /* fail */
 744                         api_ws_client_reply_fail(closure, &rb);
 745                         break;
 746                 case '*': /* broadcast */
 747                         api_ws_client_event_broadcast(closure, &rb);
 748                         break;
 749                 case '+': /* creates the event */
 750                         api_ws_client_event_create(closure, &rb);
 751                         break;
 752                 case '-': /* drops the event */
 753                         api_ws_client_event_drop(closure, &rb);
 754                         break;
 755                 case '!': /* pushs the event */
 756                         api_ws_client_event_push(closure, &rb);
 757                         break;
 758                 case 'S': /* subscribe event for a request */
 759                         api_ws_client_event_subscribe(closure, &rb);
 760                         break;
 761                 case 'U': /* unsubscribe event for a request */
 762                         api_ws_client_event_unsubscribe(closure, &rb);
 763                         break;
 764                 default: /* unexpected message */
 765                         break;
 766                 }
 767         }
 768         free(data);
 769 }
 770
 771 /* on call, propagate it to the ws service */
 772 static void api_ws_client_call_cb(void * closure, struct afb_xreq *xreq)
 773 {
 774         int rc;
 775         struct api_ws_memo *memo;
 776         struct writebuf wb = { .count = 0 };
 777         const char *raw;
 778         size_t szraw;
 779         struct api_ws *api = closure;
 780
 781         /* create the recording data */
 782         memo = api_ws_client_memo_make(api, xreq);
 783         if (memo == NULL) {
 784                 afb_xreq_fail_f(xreq, "error", "out of memory");
 785                 return;
 786         }
 787
 788         /* creates the call message */
 789         raw = afb_xreq_raw(xreq, &szraw);
 790         if (raw == NULL)
 791                 goto internal_error;
 792         if (!api_ws_write_uint32(&wb, memo->msgid)
 793          || !api_ws_write_uint32(&wb, (uint32_t)xreq->context.flags)
 794          || !api_ws_write_string(&wb, xreq->verb)
 795          || !api_ws_write_string(&wb, afb_session_uuid(xreq->context.session))
 796          || !api_ws_write_string_length(&wb, raw, szraw))
 797                 goto overflow;
 798
 799         /* send */
 800         rc = afb_ws_binary_v(api->client.ws, wb.iovec, wb.count);
 801         if (rc < 0)
 802                 goto ws_send_error;
 803         return;
 804
 805 ws_send_error:
 806         afb_xreq_fail(xreq, "error", "websocket sending error");
 807         goto clean_memo;
 808
 809 internal_error:
 810         afb_xreq_fail(xreq, "error", "internal: raw is NULL!");
 811         goto clean_memo;
 812
 813 overflow:
 814         afb_xreq_fail(xreq, "error", "overflow: size doesn't match 32 bits!");
 815
 816 clean_memo:
 817         api_ws_client_memo_destroy(memo);
 818 }
 819
 820 static int api_ws_service_start_cb(void *closure, int share_session, int onneed)
 821 {
 822         struct api_ws *api = closure;
 823
 824         /* not an error when onneed */
 825         if (onneed != 0)
 826                 return 0;
 827
 828         /* already started: it is an error */
 829         ERROR("The WS binding %s is not a startable service", api->path);
 830         return -1;
 831 }
 832
 833 /*  */
 834 static void api_ws_client_disconnect(struct api_ws *api)
 835 {
 836         if (api->fd >= 0) {
 837                 afb_ws_destroy(api->client.ws);
 838                 api->client.ws = NULL;
 839                 close(api->fd);
 840                 api->fd = -1;
 841         }
 842 }
 843
 844 /*  */
 845 static int api_ws_client_connect(struct api_ws *api)
 846 {
 847         struct afb_ws *ws;
 848         int fd;
 849
 850         fd = api_ws_socket(api->path, 0);
 851         if (fd >= 0) {
 852                 ws = afb_ws_create(afb_common_get_event_loop(), fd, &api_ws_client_ws_itf, api);
 853                 if (ws != NULL) {
 854                         api->client.ws = ws;
 855                         api->fd = fd;
 856                         return 0;
 857                 }
 858                 close(fd);
 859         }
 860         return -1;
 861 }
 862
 863 static struct afb_api_itf ws_api_itf = {
 864         .call = api_ws_client_call_cb,
 865         .service_start = api_ws_service_start_cb
 866 };
 867
 868 /* adds a afb-ws-service client api */
 869 int afb_api_ws_add_client(const char *path)
 870 {
 871         int rc;
 872         struct api_ws *api;
 873         struct afb_api afb_api;
 874
 875         /* create the ws client api */
 876         api = api_ws_make(path);
 877         if (api == NULL)
 878                 goto error;
 879
 880         /* connect to the service */
 881         rc = api_ws_client_connect(api);
 882         if (rc < 0) {
 883                 ERROR("can't connect to ws service %s", api->path);
 884                 goto error2;
 885         }
 886
 887         /* record it as an API */
 888         afb_api.closure = api;
 889         afb_api.itf = &ws_api_itf;
 890         if (afb_apis_add(api->api, afb_api) < 0)
 891                 goto error3;
 892
 893         return 0;
 894
 895 error3:
 896         api_ws_client_disconnect(api);
 897 error2:
 898         free(api);
 899 error:
 900         return -1;
 901 }
 902
 903 /******************* client description part for server *****************************/
 904
 905 static void api_ws_server_client_unref(struct api_ws_client *client)
 906 {
 907         if (!--client->refcount) {
 908                 afb_evt_listener_unref(client->listener);
 909                 afb_ws_destroy(client->ws);
 910                 afb_cred_unref(client->cred);
 911                 free(client);
 912         }
 913 }
 914
 915 /* on call, propagate it to the ws service */
 916 static void api_ws_server_called(struct api_ws_client *client, struct readbuf *rb, char *data, size_t size)
 917 {
 918         struct api_ws_server_req *wreq;
 919         const char *uuid, *verb;
 920         uint32_t flags;
 921
 922         client->refcount++;
 923
 924         /* create the request */
 925         wreq = calloc(1 , sizeof *wreq);
 926         if (wreq == NULL)
 927                 goto out_of_memory;
 928
 929         wreq->client = client;
 930         wreq->rcvdata = data;
 931
 932         /* reads the call message data */
 933         if (!api_ws_read_uint32(rb, &wreq->msgid)
 934          || !api_ws_read_uint32(rb, &flags)
 935          || !api_ws_read_string(rb, &verb, NULL)
 936          || !api_ws_read_string(rb, &uuid, NULL)
 937          || !api_ws_read_string(rb, &wreq->request, &wreq->lenreq))
 938                 goto overflow;
 939
 940         afb_xreq_init(&wreq->xreq, &afb_api_ws_xreq_itf);
 941         wreq->xreq.json = json_tokener_parse(wreq->request);
 942         if (wreq->xreq.json == NULL && strcmp(wreq->request, "null")) {
 943                 wreq->xreq.json = json_object_new_string(wreq->request);
 944         }
 945
 946         /* init the context */
 947         if (afb_context_connect(&wreq->xreq.context, uuid, NULL) < 0)
 948                 goto out_of_memory;
 949         wreq->xreq.context.flags = flags;
 950
 951         /* makes the call */
 952         wreq->xreq.cred = afb_cred_addref(client->cred);
 953         wreq->xreq.api = client->api;
 954         wreq->xreq.verb = verb;
 955         afb_apis_call(&wreq->xreq);
 956         afb_xreq_unref(&wreq->xreq);
 957         return;
 958
 959 out_of_memory:
 960 overflow:
 961         free(wreq);
 962         free(data);
 963         api_ws_server_client_unref(client);
 964 }
 965
 966 /* callback when receiving binary data */
 967 static void api_ws_server_on_binary(void *closure, char *data, size_t size)
 968 {
 969         struct readbuf rb = { .head = data, .end = data + size };
 970         api_ws_server_called(closure, &rb, data, size);
 971 }
 972
 973 /* callback when receiving a hangup */
 974 static void api_ws_server_on_hangup(void *closure)
 975 {
 976         struct api_ws_client *client = closure;
 977
 978         /* close the socket */
 979         if (client->fd >= 0) {
 980                 close(client->fd);
 981                 client->fd = -1;
 982         }
 983
 984         /* release the client */
 985         api_ws_server_client_unref(client);
 986 }
 987
 988 static void api_ws_server_accept(struct api_ws *api)
 989 {
 990         struct api_ws_client *client;
 991         struct sockaddr addr;
 992         socklen_t lenaddr;
 993
 994         client = calloc(1, sizeof *client);
 995         if (client != NULL) {
 996                 client->listener = afb_evt_listener_create(&api_ws_server_evt_itf, client);
 997                 if (client->listener != NULL) {
 998                         lenaddr = (socklen_t)sizeof addr;
 999                         client->fd = accept(api->fd, &addr, &lenaddr);
1000                         if (client->fd >= 0) {
1001                                 client->cred = afb_cred_create_for_socket(client->fd);
1002                                 fcntl(client->fd, F_SETFD, FD_CLOEXEC);
1003                                 fcntl(client->fd, F_SETFL, O_NONBLOCK);
1004                                 client->ws = afb_ws_create(afb_common_get_event_loop(), client->fd, &api_ws_server_ws_itf, client);
1005                                 if (client->ws != NULL) {
1006                                         client->api = api->api;
1007                                         client->refcount = 1;
1008                                         return;
1009                                 }
1010                                 afb_cred_unref(client->cred);
1011                                 close(client->fd);
1012                         }
1013                         afb_evt_listener_unref(client->listener);
1014                 }
1015                 free(client);
1016         }
1017 }
1018
1019 /******************* server part: manage events **********************************/
1020
1021 static void api_ws_server_event_send(struct api_ws_client *client, char order, const char *event, int eventid, const char *data)
1022 {
1023         int rc;
1024         struct writebuf wb = { .count = 0 };
1025
1026         if (api_ws_write_char(&wb, order)
1027          && api_ws_write_uint32(&wb, eventid)
1028          && api_ws_write_string(&wb, event)
1029          && (data == NULL || api_ws_write_string(&wb, data))) {
1030                 rc = afb_ws_binary_v(client->ws, wb.iovec, wb.count);
1031                 if (rc >= 0)
1032                         return;
1033         }
1034         ERROR("error while sending %c for event %s", order, event);
1035 }
1036
1037 static void api_ws_server_event_add(void *closure, const char *event, int eventid)
1038 {
1039         api_ws_server_event_send(closure, '+', event, eventid, NULL);
1040 }
1041
1042 static void api_ws_server_event_remove(void *closure, const char *event, int eventid)
1043 {
1044         api_ws_server_event_send(closure, '-', event, eventid, NULL);
1045 }
1046
1047 static void api_ws_server_event_push(void *closure, const char *event, int eventid, struct json_object *object)
1048 {
1049         const char *data = json_object_to_json_string_ext(object, JSON_C_TO_STRING_PLAIN);
1050         api_ws_server_event_send(closure, '!', event, eventid, data ? : "null");
1051         json_object_put(object);
1052 }
1053
1054 static void api_ws_server_event_broadcast(void *closure, const char *event, int eventid, struct json_object *object)
1055 {
1056         int rc;
1057         struct api_ws_client *client = closure;
1058
1059         struct writebuf wb = { .count = 0 };
1060
1061         if (api_ws_write_char(&wb, '*') && api_ws_write_string(&wb, event) && api_ws_write_object(&wb, object)) {
1062                 rc = afb_ws_binary_v(client->ws, wb.iovec, wb.count);
1063                 if (rc < 0)
1064                         ERROR("error while broadcasting event %s", event);
1065         } else
1066                 ERROR("error while broadcasting event %s", event);
1067         json_object_put(object);
1068 }
1069
1070 /******************* ws request part for server *****************/
1071
1072 /* decrement the reference count of the request and free/release it on falling to null */
1073 static void api_ws_server_req_destroy_cb(struct afb_xreq *xreq)
1074 {
1075         struct api_ws_server_req *wreq = CONTAINER_OF_XREQ(struct api_ws_server_req, xreq);
1076
1077         afb_context_disconnect(&wreq->xreq.context);
1078         afb_cred_unref(wreq->xreq.cred);
1079         json_object_put(wreq->xreq.json);
1080         free(wreq->rcvdata);
1081         api_ws_server_client_unref(wreq->client);
1082         free(wreq);
1083 }
1084
1085 static void api_ws_server_req_success_cb(struct afb_xreq *xreq, struct json_object *obj, const char *info)
1086 {
1087         int rc;
1088         struct writebuf wb = { .count = 0 };
1089         struct api_ws_server_req *wreq = CONTAINER_OF_XREQ(struct api_ws_server_req, xreq);
1090
1091         if (api_ws_write_char(&wb, 'T')
1092          && api_ws_write_uint32(&wb, wreq->msgid)
1093          && api_ws_write_uint32(&wb, (uint32_t)wreq->xreq.context.flags)
1094          && api_ws_write_string(&wb, info ? : "")
1095          && api_ws_write_object(&wb, obj)) {
1096                 rc = afb_ws_binary_v(wreq->client->ws, wb.iovec, wb.count);
1097                 if (rc >= 0)
1098                         goto success;
1099         }
1100         ERROR("error while sending success");
1101 success:
1102         json_object_put(obj);
1103 }
1104
1105 static void api_ws_server_req_fail_cb(struct afb_xreq *xreq, const char *status, const char *info)
1106 {
1107         int rc;
1108         struct writebuf wb = { .count = 0 };
1109         struct api_ws_server_req *wreq = CONTAINER_OF_XREQ(struct api_ws_server_req, xreq);
1110
1111         if (api_ws_write_char(&wb, 'F')
1112          && api_ws_write_uint32(&wb, wreq->msgid)
1113          && api_ws_write_uint32(&wb, (uint32_t)wreq->xreq.context.flags)
1114          && api_ws_write_string(&wb, status)
1115          && api_ws_write_string(&wb, info ? : "")) {
1116                 rc = afb_ws_binary_v(wreq->client->ws, wb.iovec, wb.count);
1117                 if (rc >= 0)
1118                         return;
1119         }
1120         ERROR("error while sending fail");
1121 }
1122
1123 static int api_ws_server_req_subscribe_cb(struct afb_xreq *xreq, struct afb_event event)
1124 {
1125         int rc, rc2;
1126         struct writebuf wb = { .count = 0 };
1127         struct api_ws_server_req *wreq = CONTAINER_OF_XREQ(struct api_ws_server_req, xreq);
1128
1129         rc = afb_evt_add_watch(wreq->client->listener, event);
1130         if (rc < 0)
1131                 return rc;
1132
1133         if (api_ws_write_char(&wb, 'S')
1134          && api_ws_write_uint32(&wb, wreq->msgid)
1135          && api_ws_write_uint32(&wb, (uint32_t)afb_evt_event_id(event))
1136          && api_ws_write_string(&wb, afb_evt_event_name(event))) {
1137                 rc2 = afb_ws_binary_v(wreq->client->ws, wb.iovec, wb.count);
1138                 if (rc2 >= 0)
1139                         goto success;
1140         }
1141         ERROR("error while subscribing event");
1142 success:
1143         return rc;
1144 }
1145
1146 static int api_ws_server_req_unsubscribe_cb(struct afb_xreq *xreq, struct afb_event event)
1147 {
1148         int rc, rc2;
1149         struct writebuf wb = { .count = 0 };
1150         struct api_ws_server_req *wreq = CONTAINER_OF_XREQ(struct api_ws_server_req, xreq);
1151
1152         if (api_ws_write_char(&wb, 'U')
1153          && api_ws_write_uint32(&wb, wreq->msgid)
1154          && api_ws_write_uint32(&wb, (uint32_t)afb_evt_event_id(event))
1155          && api_ws_write_string(&wb, afb_evt_event_name(event))) {
1156                 rc2 = afb_ws_binary_v(wreq->client->ws, wb.iovec, wb.count);
1157                 if (rc2 >= 0)
1158                         goto success;
1159         }
1160         ERROR("error while subscribing event");
1161 success:
1162         rc = afb_evt_remove_watch(wreq->client->listener, event);
1163         return rc;
1164 }
1165
1166 /******************* server part **********************************/
1167
1168 static int api_ws_server_connect(struct api_ws *api);
1169
1170 static int api_ws_server_listen_callback(sd_event_source *src, int fd, uint32_t revents, void *closure)
1171 {
1172         if ((revents & EPOLLIN) != 0)
1173                 api_ws_server_accept(closure);
1174         if ((revents & EPOLLHUP) != 0)
1175                 api_ws_server_connect(closure);
1176         return 0;
1177 }
1178
1179 static void api_ws_server_disconnect(struct api_ws *api)
1180 {
1181         if (api->server.listensrc != NULL) {
1182                 sd_event_source_unref(api->server.listensrc);
1183                 api->server.listensrc = NULL;
1184         }
1185         if (api->fd >= 0) {
1186                 close(api->fd);
1187                 api->fd = -1;
1188         }
1189 }
1190
1191 static int api_ws_server_connect(struct api_ws *api)
1192 {
1193         int rc;
1194
1195         /* ensure disconnected */
1196         api_ws_server_disconnect(api);
1197
1198         /* request the service object name */
1199         api->fd = api_ws_socket(api->path, 1);
1200         if (api->fd < 0)
1201                 ERROR("can't create socket %s", api->path);
1202         else {
1203                 /* listen for service */
1204                 rc = sd_event_add_io(afb_common_get_event_loop(), &api->server.listensrc, api->fd, EPOLLIN, api_ws_server_listen_callback, api);
1205                 if (rc >= 0)
1206                         return 0;
1207                 close(api->fd);
1208                 errno = -rc;
1209                 ERROR("can't add ws object %s", api->path);
1210         }
1211         return -1;
1212 }
1213
1214 /* create the service */
1215 int afb_api_ws_add_server(const char *path)
1216 {
1217         int rc;
1218         struct api_ws *api;
1219
1220         /* creates the ws api object */
1221         api = api_ws_make(path);
1222         if (api == NULL)
1223                 goto error;
1224
1225         /* connect for serving */
1226         rc = api_ws_server_connect(api);
1227         if (rc < 0)
1228                 goto error2;
1229
1230         return 0;
1231
1232 error2:
1233         free(api);
1234 error:
1235         return -1;
1236 }
1237
1238