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 #define CHAR_FOR_CALL             'C'
  57 #define CHAR_FOR_ANSWER_SUCCESS   'T'
  58 #define CHAR_FOR_ANSWER_FAIL      'F'
  59 #define CHAR_FOR_EVT_BROADCAST    '*'
  60 #define CHAR_FOR_EVT_ADD          '+'
  61 #define CHAR_FOR_EVT_DEL          '-'
  62 #define CHAR_FOR_EVT_PUSH         '!'
  63 #define CHAR_FOR_EVT_SUBSCRIBE    'S'
  64 #define CHAR_FOR_EVT_UNSUBSCRIBE  'U'
  65
  66 /*
  67  */
  68 struct api_ws
  69 {
  70         char *path;             /* path of the object for the API */
  71         char *api;              /* api name of the interface */
  72         int fd;                 /* file descriptor */
  73         union {
  74                 struct {
  75                         uint32_t id;
  76                         struct afb_ws *ws;
  77                         struct api_ws_event *events;
  78                         struct api_ws_memo *memos;
  79                 } client;
  80                 struct {
  81                         sd_event_source *listensrc;
  82                         struct afb_evt_listener *listener; /* listener for broadcasted events */
  83                 } server;
  84         };
  85 };
  86
  87 #define RETOK   1
  88 #define RETERR  2
  89 #define RETRAW  3
  90
  91 /******************* websocket interface for client part **********************************/
  92
  93 static void api_ws_client_on_binary(void *closure, char *data, size_t size);
  94
  95 static const struct afb_ws_itf api_ws_client_ws_itf =
  96 {
  97         .on_close = NULL,
  98         .on_text = NULL,
  99         .on_binary = api_ws_client_on_binary,
 100         .on_error = NULL,
 101         .on_hangup = NULL
 102 };
 103
 104 /******************* event structures for server part **********************************/
 105
 106 static void api_ws_server_event_add(void *closure, const char *event, int eventid);
 107 static void api_ws_server_event_remove(void *closure, const char *event, int eventid);
 108 static void api_ws_server_event_push(void *closure, const char *event, int eventid, struct json_object *object);
 109 static void api_ws_server_event_broadcast(void *closure, const char *event, int eventid, struct json_object *object);
 110
 111 /* the interface for events pushing */
 112 static const struct afb_evt_itf api_ws_server_evt_itf = {
 113         .broadcast = api_ws_server_event_broadcast,
 114         .push = api_ws_server_event_push,
 115         .add = api_ws_server_event_add,
 116         .remove = api_ws_server_event_remove
 117 };
 118
 119 /******************* client description part for server *****************************/
 120
 121 struct api_ws_client
 122 {
 123         /* the server ws-api */
 124         const char *api;
 125
 126         /* count of references */
 127         int refcount;
 128
 129         /* listener for events */
 130         struct afb_evt_listener *listener;
 131
 132         /* file descriptor */
 133         int fd;
 134
 135         /* websocket */
 136         struct afb_ws *ws;
 137
 138         /* credentials */
 139         struct afb_cred *cred;
 140 };
 141
 142 /******************* websocket interface for client part **********************************/
 143
 144 static void api_ws_server_on_binary(void *closure, char *data, size_t size);
 145 static void api_ws_server_on_hangup(void *closure);
 146
 147 static const struct afb_ws_itf api_ws_server_ws_itf =
 148 {
 149         .on_close = NULL,
 150         .on_text = NULL,
 151         .on_binary = api_ws_server_on_binary,
 152         .on_error = NULL,
 153         .on_hangup = api_ws_server_on_hangup
 154 };
 155
 156 /******************* ws request part for server *****************/
 157
 158 /*
 159  * structure for a ws request
 160  */
 161 struct api_ws_server_req {
 162         struct afb_xreq xreq;           /* the xreq */
 163         struct api_ws_client *client;   /* the client of the request */
 164         const char *request;            /* the readen request as string */
 165         size_t lenreq;                  /* the length of the request */
 166         uint32_t msgid;                 /* the incoming request msgid */
 167 };
 168
 169 static void api_ws_server_req_success_cb(struct afb_xreq *xreq, struct json_object *obj, const char *info);
 170 static void api_ws_server_req_fail_cb(struct afb_xreq *xreq, const char *status, const char *info);
 171 static void api_ws_server_req_destroy_cb(struct afb_xreq *xreq);
 172 static int api_ws_server_req_subscribe_cb(struct afb_xreq *xreq, struct afb_event event);
 173 static int api_ws_server_req_unsubscribe_cb(struct afb_xreq *xreq, struct afb_event event);
 174
 175 const struct afb_xreq_query_itf afb_api_ws_xreq_itf = {
 176         .success = api_ws_server_req_success_cb,
 177         .fail = api_ws_server_req_fail_cb,
 178         .unref = api_ws_server_req_destroy_cb,
 179         .subscribe = api_ws_server_req_subscribe_cb,
 180         .unsubscribe = api_ws_server_req_unsubscribe_cb
 181 };
 182
 183 /******************* common part **********************************/
 184
 185 /*
 186  * create a structure api_ws not connected to the 'path'.
 187  */
 188 static struct api_ws *api_ws_make(const char *path)
 189 {
 190         struct api_ws *api;
 191         size_t length;
 192
 193         /* allocates the structure */
 194         length = strlen(path);
 195         api = calloc(1, sizeof *api + 1 + length);
 196         if (api == NULL) {
 197                 errno = ENOMEM;
 198                 goto error;
 199         }
 200
 201         /* path is copied after the struct */
 202         api->path = (char*)(api+1);
 203         memcpy(api->path, path, length + 1);
 204
 205         /* api name is at the end of the path */
 206         while (length && path[length - 1] != '/' && path[length - 1] != ':')
 207                 length = length - 1;
 208         api->api = &api->path[length];
 209         if (api->api == NULL || !afb_apis_is_valid_api_name(api->api)) {
 210                 errno = EINVAL;
 211                 goto error2;
 212         }
 213
 214         api->fd = -1;
 215         return api;
 216
 217 error2:
 218         free(api);
 219 error:
 220         return NULL;
 221 }
 222
 223 static int api_ws_socket_unix(const char *path, int server)
 224 {
 225         int fd, rc;
 226         struct sockaddr_un addr;
 227         size_t length;
 228
 229         length = strlen(path);
 230         if (length >= 108) {
 231                 errno = ENAMETOOLONG;
 232                 return -1;
 233         }
 234
 235         if (server)
 236                 unlink(path);
 237
 238         fd = socket(AF_UNIX, SOCK_STREAM, 0);
 239         if (fd < 0)
 240                 return fd;
 241
 242         memset(&addr, 0, sizeof addr);
 243         addr.sun_family = AF_UNIX;
 244         strcpy(addr.sun_path, path);
 245         if (server) {
 246                 rc = bind(fd, (struct sockaddr *) &addr, (socklen_t)(sizeof addr));
 247         } else {
 248                 rc = connect(fd, (struct sockaddr *) &addr, (socklen_t)(sizeof addr));
 249         }
 250         if (rc < 0) {
 251                 close(fd);
 252                 return rc;
 253         }
 254         return fd;
 255 }
 256
 257 static int api_ws_socket_inet(const char *path, int server)
 258 {
 259         int rc, fd;
 260         const char *service, *host, *api;
 261         struct addrinfo hint, *rai, *iai;
 262
 263         /* scan the uri */
 264         api = strrchr(path, '/');
 265         service = strrchr(path, ':');
 266         if (api == NULL || service == NULL || api < service) {
 267                 errno = EINVAL;
 268                 return -1;
 269         }
 270         host = strndupa(path, service++ - path);
 271         service = strndupa(service, api - service);
 272
 273         /* get addr */
 274         memset(&hint, 0, sizeof hint);
 275         hint.ai_family = AF_INET;
 276         hint.ai_socktype = SOCK_STREAM;
 277         rc = getaddrinfo(host, service, &hint, &rai);
 278         if (rc != 0) {
 279                 errno = EINVAL;
 280                 return -1;
 281         }
 282
 283         /* get the socket */
 284         iai = rai;
 285         while (iai != NULL) {
 286                 fd = socket(iai->ai_family, iai->ai_socktype, iai->ai_protocol);
 287                 if (fd >= 0) {
 288                         if (server) {
 289                                 rc = bind(fd, iai->ai_addr, iai->ai_addrlen);
 290                         } else {
 291                                 rc = connect(fd, iai->ai_addr, iai->ai_addrlen);
 292                         }
 293                         if (rc == 0) {
 294                                 freeaddrinfo(rai);
 295                                 return fd;
 296                         }
 297                         close(fd);
 298                 }
 299                 iai = iai->ai_next;
 300         }
 301         freeaddrinfo(rai);
 302         return -1;
 303
 304 }
 305
 306 static int api_ws_socket(const char *path, int server)
 307 {
 308         int fd, rc;
 309
 310         /* check for systemd socket */
 311         if (0 == strncmp(path, "sd:", 3))
 312                 fd = sd_fds_for(path + 3);
 313         else {
 314                 /* check for unix socket */
 315                 if (0 == strncmp(path, "unix:", 5))
 316                         /* unix socket */
 317                         fd = api_ws_socket_unix(path + 5, server);
 318                 else
 319                         /* inet socket */
 320                         fd = api_ws_socket_inet(path, server);
 321
 322                 if (fd >= 0 && server) {
 323                         rc = 1;
 324                         setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &rc, sizeof rc);
 325                         rc = listen(fd, 5);
 326                 }
 327         }
 328         /* configure the socket */
 329         if (fd >= 0) {
 330                 fcntl(fd, F_SETFD, FD_CLOEXEC);
 331                 fcntl(fd, F_SETFL, O_NONBLOCK);
 332         }
 333         return fd;
 334 }
 335
 336 /******************* serialisation part **********************************/
 337
 338 struct readbuf
 339 {
 340         char *head, *end;
 341 };
 342
 343 #define WRITEBUF_COUNT_MAX  32
 344 struct writebuf
 345 {
 346         struct iovec iovec[WRITEBUF_COUNT_MAX];
 347         uint32_t uints[WRITEBUF_COUNT_MAX];
 348         int count;
 349 };
 350
 351 static char *api_ws_read_get(struct readbuf *rb, uint32_t length)
 352 {
 353         char *before = rb->head;
 354         char *after = before + length;
 355         if (after > rb->end)
 356                 return 0;
 357         rb->head = after;
 358         return before;
 359 }
 360
 361 static int api_ws_read_uint32(struct readbuf *rb, uint32_t *value)
 362 {
 363         char *after = rb->head + sizeof *value;
 364         if (after > rb->end)
 365                 return 0;
 366         memcpy(value, rb->head, sizeof *value);
 367         rb->head = after;
 368         *value = le32toh(*value);
 369         return 1;
 370 }
 371
 372 static int api_ws_read_string(struct readbuf *rb, const char **value, size_t *length)
 373 {
 374         uint32_t len;
 375         if (!api_ws_read_uint32(rb, &len) || !len)
 376                 return 0;
 377         if (length)
 378                 *length = (size_t)(len - 1);
 379         return (*value = api_ws_read_get(rb, len)) != NULL &&  rb->head[-1] == 0;
 380 }
 381
 382 static int api_ws_read_object(struct readbuf *rb, struct json_object **object)
 383 {
 384         size_t length;
 385         const char *string;
 386         return api_ws_read_string(rb, &string, &length) && ((*object = json_tokener_parse(string)) != NULL) == (strcmp(string, "null") != 0);
 387 }
 388
 389 static int api_ws_write_put(struct writebuf *wb, const void *value, size_t length)
 390 {
 391         int i = wb->count;
 392         if (i == WRITEBUF_COUNT_MAX)
 393                 return 0;
 394         wb->iovec[i].iov_base = (void*)value;
 395         wb->iovec[i].iov_len = length;
 396         wb->count = i + 1;
 397         return 1;
 398 }
 399
 400 static int api_ws_write_char(struct writebuf *wb, char value)
 401 {
 402         int i = wb->count;
 403         if (i == WRITEBUF_COUNT_MAX)
 404                 return 0;
 405         *(char*)&wb->uints[i] = value;
 406         wb->iovec[i].iov_base = &wb->uints[i];
 407         wb->iovec[i].iov_len = 1;
 408         wb->count = i + 1;
 409         return 1;
 410 }
 411
 412 static int api_ws_write_uint32(struct writebuf *wb, uint32_t value)
 413 {
 414         int i = wb->count;
 415         if (i == WRITEBUF_COUNT_MAX)
 416                 return 0;
 417         wb->uints[i] = htole32(value);
 418         wb->iovec[i].iov_base = &wb->uints[i];
 419         wb->iovec[i].iov_len = sizeof wb->uints[i];
 420         wb->count = i + 1;
 421         return 1;
 422 }
 423
 424 static int api_ws_write_string_length(struct writebuf *wb, const char *value, size_t length)
 425 {
 426         uint32_t len = (uint32_t)++length;
 427         return (size_t)len == length && len && api_ws_write_uint32(wb, len) && api_ws_write_put(wb, value, length);
 428 }
 429
 430 static int api_ws_write_string(struct writebuf *wb, const char *value)
 431 {
 432         return api_ws_write_string_length(wb, value, strlen(value));
 433 }
 434
 435 static int api_ws_write_object(struct writebuf *wb, struct json_object *object)
 436 {
 437         const char *string = json_object_to_json_string_ext(object, JSON_C_TO_STRING_PLAIN);
 438         return string != NULL && api_ws_write_string(wb, string);
 439 }
 440
 441
 442
 443
 444 /******************* client part **********************************/
 445
 446 /*
 447  * structure for recording query data
 448  */
 449 struct api_ws_memo {
 450         struct api_ws_memo *next;               /* the next memo */
 451         struct api_ws *api;             /* the ws api */
 452         struct afb_xreq *xreq;          /* the request handle */
 453 #if 0
 454         struct afb_req req;             /* the request handle */
 455         struct afb_context *context;    /* the context of the query */
 456 #endif
 457         uint32_t msgid;                 /* the message identifier */
 458 };
 459
 460 struct api_ws_event
 461 {
 462         struct api_ws_event *next;
 463         struct afb_event event;
 464         int eventid;
 465         int refcount;
 466 };
 467
 468 /* search a memorized request */
 469 static struct api_ws_memo *api_ws_client_memo_search(struct api_ws *api, uint32_t msgid)
 470 {
 471         struct api_ws_memo *memo;
 472
 473         memo = api->client.memos;
 474         while (memo != NULL && memo->msgid != msgid)
 475                 memo = memo->next;
 476
 477         return memo;
 478 }
 479
 480 /* search the event */
 481 static struct api_ws_event *api_ws_client_event_search(struct api_ws *api, uint32_t eventid, const char *name)
 482 {
 483         struct api_ws_event *ev;
 484
 485         ev = api->client.events;
 486         while (ev != NULL && (ev->eventid != eventid || 0 != strcmp(afb_evt_event_name(ev->event), name)))
 487                 ev = ev->next;
 488
 489         return ev;
 490 }
 491
 492
 493 /* allocates and init the memorizing data */
 494 static struct api_ws_memo *api_ws_client_memo_make(struct api_ws *api, struct afb_xreq *xreq)
 495 {
 496         struct api_ws_memo *memo;
 497
 498         memo = malloc(sizeof *memo);
 499         if (memo != NULL) {
 500                 afb_xreq_addref(xreq);
 501                 memo->xreq = xreq;
 502                 do { memo->msgid = ++api->client.id; } while(api_ws_client_memo_search(api, memo->msgid) != NULL);
 503                 memo->api = api;
 504                 memo->next = api->client.memos;
 505                 api->client.memos = memo;
 506         }
 507         return memo;
 508 }
 509
 510 /* free and release the memorizing data */
 511 static void api_ws_client_memo_destroy(struct api_ws_memo *memo)
 512 {
 513         struct api_ws_memo **prv;
 514
 515         prv = &memo->api->client.memos;
 516         while (*prv != NULL) {
 517                 if (*prv == memo) {
 518                         *prv = memo->next;
 519                         break;
 520                 }
 521                 prv = &(*prv)->next;
 522         }
 523
 524         afb_xreq_unref(memo->xreq);
 525         free(memo);
 526 }
 527
 528 /* get event data from the message */
 529 static int api_ws_client_msg_event_read(struct readbuf *rb, uint32_t *eventid, const char **name)
 530 {
 531         return api_ws_read_uint32(rb, eventid) && api_ws_read_string(rb, name, NULL);
 532 }
 533
 534 /* get event from the message */
 535 static int api_ws_client_msg_event_get(struct api_ws *api, struct readbuf *rb, struct api_ws_event **ev)
 536 {
 537         const char *name;
 538         uint32_t eventid;
 539
 540         /* get event data from the message */
 541         if (!api_ws_client_msg_event_read(rb, &eventid, &name)) {
 542                 ERROR("Invalid message");
 543                 return 0;
 544         }
 545
 546         /* check conflicts */
 547         *ev = api_ws_client_event_search(api, eventid, name);
 548         if (*ev == NULL) {
 549                 ERROR("event %s not found", name);
 550                 return 0;
 551         }
 552
 553         return 1;
 554 }
 555
 556 /* get event from the message */
 557 static int api_ws_client_msg_memo_get(struct api_ws *api, struct readbuf *rb, struct api_ws_memo **memo)
 558 {
 559         uint32_t msgid;
 560
 561         /* get event data from the message */
 562         if (!api_ws_read_uint32(rb, &msgid)) {
 563                 ERROR("Invalid message");
 564                 return 0;
 565         }
 566
 567         /* get the memo */
 568         *memo = api_ws_client_memo_search(api, msgid);
 569         if (*memo == NULL) {
 570                 ERROR("message not found");
 571                 return 0;
 572         }
 573
 574         return 1;
 575 }
 576
 577 /* read a subscrition message */
 578 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)
 579 {
 580         return api_ws_client_msg_memo_get(api, rb, memo) && api_ws_client_msg_event_get(api, rb, ev);
 581 }
 582
 583 /* adds an event */
 584 static void api_ws_client_event_create(struct api_ws *api, struct readbuf *rb)
 585 {
 586         size_t offset;
 587         const char *name;
 588         uint32_t eventid;
 589         struct api_ws_event *ev;
 590
 591         /* get event data from the message */
 592         offset = api_ws_client_msg_event_read(rb, &eventid, &name);
 593         if (offset == 0) {
 594                 ERROR("Invalid message");
 595                 return;
 596         }
 597
 598         /* check conflicts */
 599         ev = api_ws_client_event_search(api, eventid, name);
 600         if (ev != NULL) {
 601                 ev->refcount++;
 602                 return;
 603         }
 604
 605         /* no conflict, try to add it */
 606         ev = malloc(sizeof *ev);
 607         if (ev != NULL) {
 608                 ev->event = afb_evt_create_event(name);
 609                 if (ev->event.closure == NULL)
 610                         free(ev);
 611                 else {
 612                         ev->refcount = 1;
 613                         ev->eventid = eventid;
 614                         ev->next = api->client.events;
 615                         api->client.events = ev;
 616                         return;
 617                 }
 618         }
 619         ERROR("can't create event %s, out of memory", name);
 620 }
 621
 622 /* removes an event */
 623 static void api_ws_client_event_drop(struct api_ws *api, struct readbuf *rb)
 624 {
 625         struct api_ws_event *ev, **prv;
 626
 627         /* retrieves the event */
 628         if (!api_ws_client_msg_event_get(api, rb, &ev))
 629                 return;
 630
 631         /* decrease the reference count */
 632         if (--ev->refcount)
 633                 return;
 634
 635         /* unlinks the event */
 636         prv = &api->client.events;
 637         while (*prv != ev)
 638                 prv = &(*prv)->next;
 639         *prv = ev->next;
 640
 641         /* destroys the event */
 642         afb_event_drop(ev->event);
 643         free(ev);
 644 }
 645
 646 /* subscribes an event */
 647 static void api_ws_client_event_subscribe(struct api_ws *api, struct readbuf *rb)
 648 {
 649         struct api_ws_event *ev;
 650         struct api_ws_memo *memo;
 651
 652         if (api_ws_client_msg_subscription_get(api, rb, &ev, &memo)) {
 653                 /* subscribe the request from the event */
 654                 if (afb_xreq_subscribe(memo->xreq, ev->event) < 0)
 655                         ERROR("can't subscribe: %m");
 656         }
 657 }
 658
 659 /* unsubscribes an event */
 660 static void api_ws_client_event_unsubscribe(struct api_ws *api, struct readbuf *rb)
 661 {
 662         struct api_ws_event *ev;
 663         struct api_ws_memo *memo;
 664
 665         if (api_ws_client_msg_subscription_get(api, rb, &ev, &memo)) {
 666                 /* unsubscribe the request from the event */
 667                 if (afb_xreq_unsubscribe(memo->xreq, ev->event) < 0)
 668                         ERROR("can't unsubscribe: %m");
 669         }
 670 }
 671
 672 /* receives broadcasted events */
 673 static void api_ws_client_event_broadcast(struct api_ws *api, struct readbuf *rb)
 674 {
 675         struct json_object *object;
 676         const char *event;
 677
 678         if (api_ws_read_string(rb, &event, NULL) && api_ws_read_object(rb, &object))
 679                 afb_evt_broadcast(event, object);
 680         else
 681                 ERROR("unreadable broadcasted event");
 682 }
 683
 684 /* pushs an event */
 685 static void api_ws_client_event_push(struct api_ws *api, struct readbuf *rb)
 686 {
 687         struct api_ws_event *ev;
 688         struct json_object *object;
 689
 690         if (api_ws_client_msg_event_get(api, rb, &ev) && api_ws_read_object(rb, &object))
 691                 afb_event_push(ev->event, object);
 692         else
 693                 ERROR("unreadable push event");
 694 }
 695
 696 static void api_ws_client_reply_success(struct api_ws *api, struct readbuf *rb)
 697 {
 698         struct api_ws_memo *memo;
 699         struct json_object *object;
 700         const char *info;
 701         uint32_t flags;
 702
 703         /* retrieve the message data */
 704         if (!api_ws_client_msg_memo_get(api, rb, &memo))
 705                 return;
 706
 707         if (api_ws_read_uint32(rb, &flags)
 708          && api_ws_read_string(rb, &info, NULL)
 709          && api_ws_read_object(rb, &object)) {
 710                 memo->xreq->context.flags = (unsigned)flags;
 711                 afb_xreq_success(memo->xreq, object, *info ? info : NULL);
 712         } else {
 713                 /* failing to have the answer */
 714                 afb_xreq_fail(memo->xreq, "error", "ws error");
 715         }
 716         api_ws_client_memo_destroy(memo);
 717 }
 718
 719 static void api_ws_client_reply_fail(struct api_ws *api, struct readbuf *rb)
 720 {
 721         struct api_ws_memo *memo;
 722         const char *info, *status;
 723         uint32_t flags;
 724
 725         /* retrieve the message data */
 726         if (!api_ws_client_msg_memo_get(api, rb, &memo))
 727                 return;
 728
 729         if (api_ws_read_uint32(rb, &flags)
 730          && api_ws_read_string(rb, &status, NULL)
 731          && api_ws_read_string(rb, &info, NULL)) {
 732                 memo->xreq->context.flags = (unsigned)flags;
 733                 afb_xreq_fail(memo->xreq, status, *info ? info : NULL);
 734         } else {
 735                 /* failing to have the answer */
 736                 afb_xreq_fail(memo->xreq, "error", "ws error");
 737         }
 738         api_ws_client_memo_destroy(memo);
 739 }
 740
 741 /* callback when receiving binary data */
 742 static void api_ws_client_on_binary(void *closure, char *data, size_t size)
 743 {
 744         if (size > 0) {
 745                 struct readbuf rb = { .head = data, .end = data + size };
 746                 switch (*rb.head++) {
 747                 case CHAR_FOR_ANSWER_SUCCESS: /* success */
 748                         api_ws_client_reply_success(closure, &rb);
 749                         break;
 750                 case CHAR_FOR_ANSWER_FAIL: /* fail */
 751                         api_ws_client_reply_fail(closure, &rb);
 752                         break;
 753                 case CHAR_FOR_EVT_BROADCAST: /* broadcast */
 754                         api_ws_client_event_broadcast(closure, &rb);
 755                         break;
 756                 case CHAR_FOR_EVT_ADD: /* creates the event */
 757                         api_ws_client_event_create(closure, &rb);
 758                         break;
 759                 case CHAR_FOR_EVT_DEL: /* drops the event */
 760                         api_ws_client_event_drop(closure, &rb);
 761                         break;
 762                 case CHAR_FOR_EVT_PUSH: /* pushs the event */
 763                         api_ws_client_event_push(closure, &rb);
 764                         break;
 765                 case CHAR_FOR_EVT_SUBSCRIBE: /* subscribe event for a request */
 766                         api_ws_client_event_subscribe(closure, &rb);
 767                         break;
 768                 case CHAR_FOR_EVT_UNSUBSCRIBE: /* unsubscribe event for a request */
 769                         api_ws_client_event_unsubscribe(closure, &rb);
 770                         break;
 771                 default: /* unexpected message */
 772                         break;
 773                 }
 774         }
 775         free(data);
 776 }
 777
 778 /* on call, propagate it to the ws service */
 779 static void api_ws_client_call_cb(void * closure, struct afb_xreq *xreq)
 780 {
 781         int rc;
 782         struct api_ws_memo *memo;
 783         struct writebuf wb = { .count = 0 };
 784         const char *raw;
 785         size_t szraw;
 786         struct api_ws *api = closure;
 787
 788         /* create the recording data */
 789         memo = api_ws_client_memo_make(api, xreq);
 790         if (memo == NULL) {
 791                 afb_xreq_fail_f(xreq, "error", "out of memory");
 792                 return;
 793         }
 794
 795         /* creates the call message */
 796         raw = afb_xreq_raw(xreq, &szraw);
 797         if (raw == NULL)
 798                 goto internal_error;
 799         if (!api_ws_write_char(&wb, CHAR_FOR_CALL)
 800          || !api_ws_write_uint32(&wb, memo->msgid)
 801          || !api_ws_write_uint32(&wb, (uint32_t)xreq->context.flags)
 802          || !api_ws_write_string(&wb, xreq->verb)
 803          || !api_ws_write_string(&wb, afb_session_uuid(xreq->context.session))
 804          || !api_ws_write_string_length(&wb, raw, szraw))
 805                 goto overflow;
 806
 807         /* send */
 808         rc = afb_ws_binary_v(api->client.ws, wb.iovec, wb.count);
 809         if (rc < 0)
 810                 goto ws_send_error;
 811         return;
 812
 813 ws_send_error:
 814         afb_xreq_fail(xreq, "error", "websocket sending error");
 815         goto clean_memo;
 816
 817 internal_error:
 818         afb_xreq_fail(xreq, "error", "internal: raw is NULL!");
 819         goto clean_memo;
 820
 821 overflow:
 822         afb_xreq_fail(xreq, "error", "overflow: size doesn't match 32 bits!");
 823
 824 clean_memo:
 825         api_ws_client_memo_destroy(memo);
 826 }
 827
 828 static int api_ws_service_start_cb(void *closure, int share_session, int onneed)
 829 {
 830         struct api_ws *api = closure;
 831
 832         /* not an error when onneed */
 833         if (onneed != 0)
 834                 return 0;
 835
 836         /* already started: it is an error */
 837         ERROR("The WS binding %s is not a startable service", api->path);
 838         return -1;
 839 }
 840
 841 /*  */
 842 static void api_ws_client_disconnect(struct api_ws *api)
 843 {
 844         if (api->fd >= 0) {
 845                 afb_ws_destroy(api->client.ws);
 846                 api->client.ws = NULL;
 847                 close(api->fd);
 848                 api->fd = -1;
 849         }
 850 }
 851
 852 /*  */
 853 static int api_ws_client_connect(struct api_ws *api)
 854 {
 855         struct afb_ws *ws;
 856         int fd;
 857
 858         fd = api_ws_socket(api->path, 0);
 859         if (fd >= 0) {
 860                 ws = afb_ws_create(afb_common_get_event_loop(), fd, &api_ws_client_ws_itf, api);
 861                 if (ws != NULL) {
 862                         api->client.ws = ws;
 863                         api->fd = fd;
 864                         return 0;
 865                 }
 866                 close(fd);
 867         }
 868         return -1;
 869 }
 870
 871 static struct afb_api_itf ws_api_itf = {
 872         .call = api_ws_client_call_cb,
 873         .service_start = api_ws_service_start_cb
 874 };
 875
 876 /* adds a afb-ws-service client api */
 877 int afb_api_ws_add_client(const char *path)
 878 {
 879         int rc;
 880         struct api_ws *api;
 881         struct afb_api afb_api;
 882
 883         /* create the ws client api */
 884         api = api_ws_make(path);
 885         if (api == NULL)
 886                 goto error;
 887
 888         /* connect to the service */
 889         rc = api_ws_client_connect(api);
 890         if (rc < 0) {
 891                 ERROR("can't connect to ws service %s", api->path);
 892                 goto error2;
 893         }
 894
 895         /* record it as an API */
 896         afb_api.closure = api;
 897         afb_api.itf = &ws_api_itf;
 898         if (afb_apis_add(api->api, afb_api) < 0)
 899                 goto error3;
 900
 901         return 0;
 902
 903 error3:
 904         api_ws_client_disconnect(api);
 905 error2:
 906         free(api);
 907 error:
 908         return -1;
 909 }
 910
 911 /******************* client description part for server *****************************/
 912
 913 static void api_ws_server_client_unref(struct api_ws_client *client)
 914 {
 915         if (!--client->refcount) {
 916                 afb_evt_listener_unref(client->listener);
 917                 afb_ws_destroy(client->ws);
 918                 afb_cred_unref(client->cred);
 919                 free(client);
 920         }
 921 }
 922
 923 /* on call, propagate it to the ws service */
 924 static void api_ws_server_on_call(struct api_ws_client *client, struct readbuf *rb)
 925 {
 926         struct api_ws_server_req *wreq;
 927         const char *uuid, *verb;
 928         uint32_t flags;
 929
 930         client->refcount++;
 931
 932         /* create the request */
 933         wreq = calloc(1 , sizeof *wreq);
 934         if (wreq == NULL)
 935                 goto out_of_memory;
 936
 937         wreq->client = client;
 938
 939         /* reads the call message data */
 940         if (!api_ws_read_uint32(rb, &wreq->msgid)
 941          || !api_ws_read_uint32(rb, &flags)
 942          || !api_ws_read_string(rb, &verb, NULL)
 943          || !api_ws_read_string(rb, &uuid, NULL)
 944          || !api_ws_read_string(rb, &wreq->request, &wreq->lenreq))
 945                 goto overflow;
 946
 947         afb_xreq_init(&wreq->xreq, &afb_api_ws_xreq_itf);
 948         wreq->xreq.json = json_tokener_parse(wreq->request);
 949         if (wreq->xreq.json == NULL && strcmp(wreq->request, "null")) {
 950                 wreq->xreq.json = json_object_new_string(wreq->request);
 951         }
 952
 953         /* init the context */
 954         if (afb_context_connect(&wreq->xreq.context, uuid, NULL) < 0)
 955                 goto out_of_memory;
 956         wreq->xreq.context.flags = flags;
 957
 958         /* makes the call */
 959         wreq->xreq.cred = afb_cred_addref(client->cred);
 960         wreq->xreq.api = client->api;
 961         wreq->xreq.verb = verb;
 962         afb_apis_call(&wreq->xreq);
 963         afb_xreq_unref(&wreq->xreq);
 964         return;
 965
 966 out_of_memory:
 967 overflow:
 968         free(wreq);
 969         api_ws_server_client_unref(client);
 970 }
 971
 972 /* callback when receiving binary data */
 973 static void api_ws_server_on_binary(void *closure, char *data, size_t size)
 974 {
 975         if (size > 0) {
 976                 struct readbuf rb = { .head = data, .end = data + size };
 977                 switch (*rb.head++) {
 978                 case CHAR_FOR_CALL:
 979                         api_ws_server_on_call(closure, &rb);
 980                         break;
 981                 default: /* unexpected message */
 982                         /* TODO: close the connection */
 983                         break;
 984                 }
 985         }
 986         free(data);
 987 }
 988
 989 /* callback when receiving a hangup */
 990 static void api_ws_server_on_hangup(void *closure)
 991 {
 992         struct api_ws_client *client = closure;
 993
 994         /* close the socket */
 995         if (client->fd >= 0) {
 996                 close(client->fd);
 997                 client->fd = -1;
 998         }
 999
1000         /* release the client */
1001         api_ws_server_client_unref(client);
1002 }
1003
1004 static void api_ws_server_accept(struct api_ws *api)
1005 {
1006         struct api_ws_client *client;
1007         struct sockaddr addr;
1008         socklen_t lenaddr;
1009
1010         client = calloc(1, sizeof *client);
1011         if (client != NULL) {
1012                 client->listener = afb_evt_listener_create(&api_ws_server_evt_itf, client);
1013                 if (client->listener != NULL) {
1014                         lenaddr = (socklen_t)sizeof addr;
1015                         client->fd = accept(api->fd, &addr, &lenaddr);
1016                         if (client->fd >= 0) {
1017                                 client->cred = afb_cred_create_for_socket(client->fd);
1018                                 fcntl(client->fd, F_SETFD, FD_CLOEXEC);
1019                                 fcntl(client->fd, F_SETFL, O_NONBLOCK);
1020                                 client->ws = afb_ws_create(afb_common_get_event_loop(), client->fd, &api_ws_server_ws_itf, client);
1021                                 if (client->ws != NULL) {
1022                                         client->api = api->api;
1023                                         client->refcount = 1;
1024                                         return;
1025                                 }
1026                                 afb_cred_unref(client->cred);
1027                                 close(client->fd);
1028                         }
1029                         afb_evt_listener_unref(client->listener);
1030                 }
1031                 free(client);
1032         }
1033 }
1034
1035 /******************* server part: manage events **********************************/
1036
1037 static void api_ws_server_event_send(struct api_ws_client *client, char order, const char *event, int eventid, const char *data)
1038 {
1039         int rc;
1040         struct writebuf wb = { .count = 0 };
1041
1042         if (api_ws_write_char(&wb, order)
1043          && api_ws_write_uint32(&wb, eventid)
1044          && api_ws_write_string(&wb, event)
1045          && (data == NULL || api_ws_write_string(&wb, data))) {
1046                 rc = afb_ws_binary_v(client->ws, wb.iovec, wb.count);
1047                 if (rc >= 0)
1048                         return;
1049         }
1050         ERROR("error while sending %c for event %s", order, event);
1051 }
1052
1053 static void api_ws_server_event_add(void *closure, const char *event, int eventid)
1054 {
1055         api_ws_server_event_send(closure, CHAR_FOR_EVT_ADD, event, eventid, NULL);
1056 }
1057
1058 static void api_ws_server_event_remove(void *closure, const char *event, int eventid)
1059 {
1060         api_ws_server_event_send(closure, CHAR_FOR_EVT_DEL, event, eventid, NULL);
1061 }
1062
1063 static void api_ws_server_event_push(void *closure, const char *event, int eventid, struct json_object *object)
1064 {
1065         const char *data = json_object_to_json_string_ext(object, JSON_C_TO_STRING_PLAIN);
1066         api_ws_server_event_send(closure, CHAR_FOR_EVT_PUSH, event, eventid, data ? : "null");
1067         json_object_put(object);
1068 }
1069
1070 static void api_ws_server_event_broadcast(void *closure, const char *event, int eventid, struct json_object *object)
1071 {
1072         int rc;
1073         struct api_ws_client *client = closure;
1074
1075         struct writebuf wb = { .count = 0 };
1076
1077         if (api_ws_write_char(&wb, CHAR_FOR_EVT_BROADCAST) && api_ws_write_string(&wb, event) && api_ws_write_object(&wb, object)) {
1078                 rc = afb_ws_binary_v(client->ws, wb.iovec, wb.count);
1079                 if (rc < 0)
1080                         ERROR("error while broadcasting event %s", event);
1081         } else
1082                 ERROR("error while broadcasting event %s", event);
1083         json_object_put(object);
1084 }
1085
1086 /******************* ws request part for server *****************/
1087
1088 /* decrement the reference count of the request and free/release it on falling to null */
1089 static void api_ws_server_req_destroy_cb(struct afb_xreq *xreq)
1090 {
1091         struct api_ws_server_req *wreq = CONTAINER_OF_XREQ(struct api_ws_server_req, xreq);
1092
1093         afb_context_disconnect(&wreq->xreq.context);
1094         afb_cred_unref(wreq->xreq.cred);
1095         json_object_put(wreq->xreq.json);
1096         api_ws_server_client_unref(wreq->client);
1097         free(wreq);
1098 }
1099
1100 static void api_ws_server_req_success_cb(struct afb_xreq *xreq, struct json_object *obj, const char *info)
1101 {
1102         int rc;
1103         struct writebuf wb = { .count = 0 };
1104         struct api_ws_server_req *wreq = CONTAINER_OF_XREQ(struct api_ws_server_req, xreq);
1105
1106         if (api_ws_write_char(&wb, CHAR_FOR_ANSWER_SUCCESS)
1107          && api_ws_write_uint32(&wb, wreq->msgid)
1108          && api_ws_write_uint32(&wb, (uint32_t)wreq->xreq.context.flags)
1109          && api_ws_write_string(&wb, info ? : "")
1110          && api_ws_write_object(&wb, obj)) {
1111                 rc = afb_ws_binary_v(wreq->client->ws, wb.iovec, wb.count);
1112                 if (rc >= 0)
1113                         goto success;
1114         }
1115         ERROR("error while sending success");
1116 success:
1117         json_object_put(obj);
1118 }
1119
1120 static void api_ws_server_req_fail_cb(struct afb_xreq *xreq, const char *status, const char *info)
1121 {
1122         int rc;
1123         struct writebuf wb = { .count = 0 };
1124         struct api_ws_server_req *wreq = CONTAINER_OF_XREQ(struct api_ws_server_req, xreq);
1125
1126         if (api_ws_write_char(&wb, CHAR_FOR_ANSWER_FAIL)
1127          && api_ws_write_uint32(&wb, wreq->msgid)
1128          && api_ws_write_uint32(&wb, (uint32_t)wreq->xreq.context.flags)
1129          && api_ws_write_string(&wb, status)
1130          && api_ws_write_string(&wb, info ? : "")) {
1131                 rc = afb_ws_binary_v(wreq->client->ws, wb.iovec, wb.count);
1132                 if (rc >= 0)
1133                         return;
1134         }
1135         ERROR("error while sending fail");
1136 }
1137
1138 static int api_ws_server_req_subscribe_cb(struct afb_xreq *xreq, struct afb_event event)
1139 {
1140         int rc, rc2;
1141         struct writebuf wb = { .count = 0 };
1142         struct api_ws_server_req *wreq = CONTAINER_OF_XREQ(struct api_ws_server_req, xreq);
1143
1144         rc = afb_evt_add_watch(wreq->client->listener, event);
1145         if (rc < 0)
1146                 return rc;
1147
1148         if (api_ws_write_char(&wb, CHAR_FOR_EVT_SUBSCRIBE)
1149          && api_ws_write_uint32(&wb, wreq->msgid)
1150          && api_ws_write_uint32(&wb, (uint32_t)afb_evt_event_id(event))
1151          && api_ws_write_string(&wb, afb_evt_event_name(event))) {
1152                 rc2 = afb_ws_binary_v(wreq->client->ws, wb.iovec, wb.count);
1153                 if (rc2 >= 0)
1154                         goto success;
1155         }
1156         ERROR("error while subscribing event");
1157 success:
1158         return rc;
1159 }
1160
1161 static int api_ws_server_req_unsubscribe_cb(struct afb_xreq *xreq, struct afb_event event)
1162 {
1163         int rc, rc2;
1164         struct writebuf wb = { .count = 0 };
1165         struct api_ws_server_req *wreq = CONTAINER_OF_XREQ(struct api_ws_server_req, xreq);
1166
1167         if (api_ws_write_char(&wb, CHAR_FOR_EVT_UNSUBSCRIBE)
1168          && api_ws_write_uint32(&wb, wreq->msgid)
1169          && api_ws_write_uint32(&wb, (uint32_t)afb_evt_event_id(event))
1170          && api_ws_write_string(&wb, afb_evt_event_name(event))) {
1171                 rc2 = afb_ws_binary_v(wreq->client->ws, wb.iovec, wb.count);
1172                 if (rc2 >= 0)
1173                         goto success;
1174         }
1175         ERROR("error while subscribing event");
1176 success:
1177         rc = afb_evt_remove_watch(wreq->client->listener, event);
1178         return rc;
1179 }
1180
1181 /******************* server part **********************************/
1182
1183 static int api_ws_server_connect(struct api_ws *api);
1184
1185 static int api_ws_server_listen_callback(sd_event_source *src, int fd, uint32_t revents, void *closure)
1186 {
1187         if ((revents & EPOLLIN) != 0)
1188                 api_ws_server_accept(closure);
1189         if ((revents & EPOLLHUP) != 0)
1190                 api_ws_server_connect(closure);
1191         return 0;
1192 }
1193
1194 static void api_ws_server_disconnect(struct api_ws *api)
1195 {
1196         if (api->server.listensrc != NULL) {
1197                 sd_event_source_unref(api->server.listensrc);
1198                 api->server.listensrc = NULL;
1199         }
1200         if (api->fd >= 0) {
1201                 close(api->fd);
1202                 api->fd = -1;
1203         }
1204 }
1205
1206 static int api_ws_server_connect(struct api_ws *api)
1207 {
1208         int rc;
1209
1210         /* ensure disconnected */
1211         api_ws_server_disconnect(api);
1212
1213         /* request the service object name */
1214         api->fd = api_ws_socket(api->path, 1);
1215         if (api->fd < 0)
1216                 ERROR("can't create socket %s", api->path);
1217         else {
1218                 /* listen for service */
1219                 rc = sd_event_add_io(afb_common_get_event_loop(), &api->server.listensrc, api->fd, EPOLLIN, api_ws_server_listen_callback, api);
1220                 if (rc >= 0)
1221                         return 0;
1222                 close(api->fd);
1223                 errno = -rc;
1224                 ERROR("can't add ws object %s", api->path);
1225         }
1226         return -1;
1227 }
1228
1229 /* create the service */
1230 int afb_api_ws_add_server(const char *path)
1231 {
1232         int rc;
1233         struct api_ws *api;
1234
1235         /* creates the ws api object */
1236         api = api_ws_make(path);
1237         if (api == NULL)
1238                 goto error;
1239
1240         /* connect for serving */
1241         rc = api_ws_server_connect(api);
1242         if (rc < 0)
1243                 goto error2;
1244
1245         return 0;
1246
1247 error2:
1248         free(api);
1249 error:
1250         return -1;
1251 }
1252
1253