src/afb-proto-ws.c

   1 /*
   2  * Copyright (C) 2015-2020 "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
  20 #include <stdlib.h>
  21 #include <string.h>
  22 #include <assert.h>
  23 #include <fcntl.h>
  24 #include <unistd.h>
  25 #include <errno.h>
  26 #include <endian.h>
  27 #include <netdb.h>
  28 #include <sys/types.h>
  29 #include <sys/socket.h>
  30 #include <sys/un.h>
  31 #include <pthread.h>
  32
  33 #include <json-c/json.h>
  34
  35 #include "afb-ws.h"
  36 #include "afb-msg-json.h"
  37 #include "afb-proto-ws.h"
  38 #include "fdev.h"
  39 #include "verbose.h"
  40
  41 struct afb_proto_ws;
  42
  43 /******** implementation of internal binder protocol per api **************/
  44 /*
  45
  46 This protocol is asymmetric: there is a client and a server
  47
  48 The client can require the following actions:
  49
  50   - call a verb
  51
  52   - ask for description
  53
  54 The server must reply to the previous actions by
  55
  56   - answering success or failure of the call
  57
  58   - answering the required description
  59
  60 The server can also within the context of a call
  61
  62   - subscribe or unsubscribe an event
  63
  64 For the purpose of handling events the server can:
  65
  66   - create/destroy an event
  67
  68   - push or broadcast data as an event
  69
  70   - signal unexpected event
  71
  72 */
  73 /************** constants for protocol definition *************************/
  74
  75 #define CHAR_FOR_CALL             'K'   /* client -> server */
  76 #define CHAR_FOR_REPLY            'k'   /* server -> client */
  77 #define CHAR_FOR_EVT_BROADCAST    'B'   /* server -> client */
  78 #define CHAR_FOR_EVT_ADD          'E'   /* server -> client */
  79 #define CHAR_FOR_EVT_DEL          'e'   /* server -> client */
  80 #define CHAR_FOR_EVT_PUSH         'P'   /* server -> client */
  81 #define CHAR_FOR_EVT_SUBSCRIBE    'X'   /* server -> client */
  82 #define CHAR_FOR_EVT_UNSUBSCRIBE  'x'   /* server -> client */
  83 #define CHAR_FOR_EVT_UNEXPECTED   'U'   /* client -> server */
  84 #define CHAR_FOR_DESCRIBE         'D'   /* client -> server */
  85 #define CHAR_FOR_DESCRIPTION      'd'   /* server -> client */
  86 #define CHAR_FOR_TOKEN_ADD        'T'   /* client -> server */
  87 #define CHAR_FOR_TOKEN_DROP       't'   /* client -> server */
  88 #define CHAR_FOR_SESSION_ADD      'S'   /* client -> server */
  89 #define CHAR_FOR_SESSION_DROP     's'   /* client -> server */
  90 #define CHAR_FOR_VERSION_OFFER    'V'   /* client -> server */
  91 #define CHAR_FOR_VERSION_SET      'v'   /* server -> client */
  92
  93 /******************* manage versions *****************************/
  94
  95 #define WSAPI_IDENTIFIER        02723012011  /* wsapi: 23.19.1.16.9 */
  96
  97 #define WSAPI_VERSION_UNSET     0
  98 #define WSAPI_VERSION_1         1
  99
 100 #define WSAPI_VERSION_MIN       WSAPI_VERSION_1
 101 #define WSAPI_VERSION_MAX       WSAPI_VERSION_1
 102
 103 /******************* maximum count of ids ***********************/
 104
 105 #define ACTIVE_ID_MAX           4095
 106
 107 /******************* handling calls *****************************/
 108
 109 /*
 110  * structure for recording calls on client side
 111  */
 112 struct client_call {
 113         struct client_call *next;       /* the next call */
 114         void *request;                  /* the request closure */
 115         uint16_t callid;                /* the message identifier */
 116 };
 117
 118 /*
 119  * structure for a ws request
 120  */
 121 struct afb_proto_ws_call {
 122         struct afb_proto_ws *protows;   /* the client of the request */
 123         char *buffer;                   /* the incoming buffer */
 124         uint16_t refcount;              /* reference count */
 125         uint16_t callid;                /* the incoming request callid */
 126 };
 127
 128 /*
 129  * structure for recording describe requests
 130  */
 131 struct client_describe
 132 {
 133         struct client_describe *next;
 134         void (*callback)(void*, struct json_object*);
 135         void *closure;
 136         uint16_t descid;
 137 };
 138
 139 /*
 140  * structure for jobs of describing
 141  */
 142 struct afb_proto_ws_describe
 143 {
 144         struct afb_proto_ws *protows;
 145         uint16_t descid;
 146 };
 147
 148 /******************* proto description for client or servers ******************/
 149
 150 struct afb_proto_ws
 151 {
 152         /* count of references */
 153         uint16_t refcount;
 154
 155         /* id generator */
 156         uint16_t genid;
 157
 158         /* count actives ids */
 159         uint16_t idcount;
 160
 161         /* version */
 162         uint8_t version;
 163
 164         /* resource control */
 165         pthread_mutex_t mutex;
 166
 167         /* websocket */
 168         struct afb_ws *ws;
 169
 170         /* the client closure */
 171         void *closure;
 172
 173         /* the client side interface */
 174         const struct afb_proto_ws_client_itf *client_itf;
 175
 176         /* the server side interface */
 177         const struct afb_proto_ws_server_itf *server_itf;
 178
 179         /* emitted calls (client side) */
 180         struct client_call *calls;
 181
 182         /* pending description (client side) */
 183         struct client_describe *describes;
 184
 185         /* on hangup callback */
 186         void (*on_hangup)(void *closure);
 187
 188         /* queuing facility for processing messages */
 189         int (*queuing)(struct afb_proto_ws *proto, void (*process)(int s, void *c), void *closure);
 190 };
 191
 192 /******************* streaming objects **********************************/
 193
 194 #define WRITEBUF_COUNT_MAX      32
 195 #define WRITEBUF_BUFSZ          (WRITEBUF_COUNT_MAX * sizeof(uint32_t))
 196
 197 struct writebuf
 198 {
 199         int iovcount, bufcount;
 200         struct iovec iovec[WRITEBUF_COUNT_MAX];
 201         char buf[WRITEBUF_BUFSZ];
 202 };
 203
 204 struct readbuf
 205 {
 206         char *base, *head, *end;
 207 };
 208
 209 struct binary
 210 {
 211         struct afb_proto_ws *protows;
 212         struct readbuf rb;
 213 };
 214
 215 /******************* serialization part **********************************/
 216
 217 static char *readbuf_get(struct readbuf *rb, uint32_t length)
 218 {
 219         char *before = rb->head;
 220         char *after = before + length;
 221         if (after > rb->end)
 222                 return 0;
 223         rb->head = after;
 224         return before;
 225 }
 226
 227 static int readbuf_getat(struct readbuf *rb, void *to, uint32_t length)
 228 {
 229         char *head = readbuf_get(rb, length);
 230         if (!head)
 231                 return 0;
 232         memcpy(to, head, length);
 233         return 1;
 234 }
 235
 236 __attribute__((unused))
 237 static int readbuf_char(struct readbuf *rb, char *value)
 238 {
 239         return readbuf_getat(rb, value, sizeof *value);
 240 }
 241
 242 static int readbuf_uint32(struct readbuf *rb, uint32_t *value)
 243 {
 244         int r = readbuf_getat(rb, value, sizeof *value);
 245         if (r)
 246                 *value = le32toh(*value);
 247         return r;
 248 }
 249
 250 static int readbuf_uint16(struct readbuf *rb, uint16_t *value)
 251 {
 252         int r = readbuf_getat(rb, value, sizeof *value);
 253         if (r)
 254                 *value = le16toh(*value);
 255         return r;
 256 }
 257
 258 static int readbuf_uint8(struct readbuf *rb, uint8_t *value)
 259 {
 260         return readbuf_getat(rb, value, sizeof *value);
 261 }
 262
 263 static int _readbuf_string_(struct readbuf *rb, const char **value, size_t *length, int nulok)
 264 {
 265         uint32_t len;
 266         if (!readbuf_uint32(rb, &len))
 267                 return 0;
 268         if (!len) {
 269                 if (!nulok)
 270                         return 0;
 271                 *value = NULL;
 272                 if (length)
 273                         *length = 0;
 274                 return 1;
 275         }
 276         if (length)
 277                 *length = (size_t)(len - 1);
 278         return (*value = readbuf_get(rb, len)) != NULL &&  rb->head[-1] == 0;
 279 }
 280
 281
 282 static int readbuf_string(struct readbuf *rb, const char **value, size_t *length)
 283 {
 284         return _readbuf_string_(rb, value, length, 0);
 285 }
 286
 287 static int readbuf_nullstring(struct readbuf *rb, const char **value, size_t *length)
 288 {
 289         return _readbuf_string_(rb, value, length, 1);
 290 }
 291
 292 static int readbuf_object(struct readbuf *rb, struct json_object **object)
 293 {
 294         const char *string;
 295         struct json_object *o;
 296         enum json_tokener_error jerr;
 297         int rc = readbuf_string(rb, &string, NULL);
 298         if (rc) {
 299                 o = json_tokener_parse_verbose(string, &jerr);
 300                 if (jerr != json_tokener_success)
 301                         o = json_object_new_string(string);
 302                 *object = o;
 303         }
 304         return rc;
 305 }
 306
 307 static int writebuf_put(struct writebuf *wb, const void *value, size_t length)
 308 {
 309         int i = wb->iovcount;
 310         if (i == WRITEBUF_COUNT_MAX)
 311                 return 0;
 312         wb->iovec[i].iov_base = (void*)value;
 313         wb->iovec[i].iov_len = length;
 314         wb->iovcount = i + 1;
 315         return 1;
 316 }
 317
 318 static int writebuf_putbuf(struct writebuf *wb, const void *value, int length)
 319 {
 320         char *p;
 321         int i = wb->iovcount, n = wb->bufcount, nafter;
 322
 323         /* check enough length */
 324         nafter = n + length;
 325         if (nafter > WRITEBUF_BUFSZ)
 326                 return 0;
 327
 328         /* get where to store */
 329         p = &wb->buf[n];
 330         if (i && p == (((char*)wb->iovec[i - 1].iov_base) + wb->iovec[i - 1].iov_len))
 331                 /* increase previous iovec */
 332                 wb->iovec[i - 1].iov_len += (size_t)length;
 333         else if (i == WRITEBUF_COUNT_MAX)
 334                 /* no more iovec */
 335                 return 0;
 336         else {
 337                 /* new iovec */
 338                 wb->iovec[i].iov_base = p;
 339                 wb->iovec[i].iov_len = (size_t)length;
 340                 wb->iovcount = i + 1;
 341         }
 342         /* store now */
 343         memcpy(p, value, (size_t)length);
 344         wb->bufcount = nafter;
 345         return 1;
 346 }
 347
 348 __attribute__((unused))
 349 static int writebuf_char(struct writebuf *wb, char value)
 350 {
 351         return writebuf_putbuf(wb, &value, 1);
 352 }
 353
 354 static int writebuf_uint32(struct writebuf *wb, uint32_t value)
 355 {
 356         value = htole32(value);
 357         return writebuf_putbuf(wb, &value, (int)sizeof value);
 358 }
 359
 360 static int writebuf_uint16(struct writebuf *wb, uint16_t value)
 361 {
 362         value = htole16(value);
 363         return writebuf_putbuf(wb, &value, (int)sizeof value);
 364 }
 365
 366 static int writebuf_uint8(struct writebuf *wb, uint8_t value)
 367 {
 368         return writebuf_putbuf(wb, &value, (int)sizeof value);
 369 }
 370
 371 static int writebuf_string_length(struct writebuf *wb, const char *value, size_t length)
 372 {
 373         uint32_t len = (uint32_t)++length;
 374         return (size_t)len == length && len && writebuf_uint32(wb, len) && writebuf_put(wb, value, length);
 375 }
 376
 377 static int writebuf_string(struct writebuf *wb, const char *value)
 378 {
 379         return writebuf_string_length(wb, value, strlen(value));
 380 }
 381
 382 static int writebuf_nullstring(struct writebuf *wb, const char *value)
 383 {
 384         return value ? writebuf_string_length(wb, value, strlen(value)) : writebuf_uint32(wb, 0);
 385 }
 386
 387 static int writebuf_object(struct writebuf *wb, struct json_object *object)
 388 {
 389         const char *string = json_object_to_json_string_ext(object, JSON_C_TO_STRING_PLAIN);
 390         return string != NULL && writebuf_string(wb, string);
 391 }
 392
 393 /******************* queuing of messages *****************/
 394
 395 /* queue the processing of the received message (except if size=0 cause it's not a valid message) */
 396 static void queue_message_processing(struct afb_proto_ws *protows, char *data, size_t size, void (*processing)(int,void*))
 397 {
 398         struct binary *binary;
 399
 400         if (size) {
 401                 binary = malloc(sizeof *binary);
 402                 if (!binary) {
 403                         /* TODO process the problem */
 404                         errno = ENOMEM;
 405                 } else {
 406                         binary->protows = protows;
 407                         binary->rb.base = data;
 408                         binary->rb.head = data;
 409                         binary->rb.end = data + size;
 410                         if (!protows->queuing
 411                          || protows->queuing(protows, processing, binary) < 0)
 412                                 processing(0, binary);
 413                         return;
 414                 }
 415         }
 416         free(data);
 417 }
 418
 419 /******************* sending messages *****************/
 420
 421 static int proto_write(struct afb_proto_ws *protows, struct writebuf *wb)
 422 {
 423         int rc;
 424         struct afb_ws *ws;
 425
 426         pthread_mutex_lock(&protows->mutex);
 427         ws = protows->ws;
 428         if (ws == NULL) {
 429                 errno = EPIPE;
 430                 rc = -1;
 431         } else {
 432                 rc = afb_ws_binary_v(ws, wb->iovec, wb->iovcount);
 433                 if (rc > 0)
 434                         rc = 0;
 435         }
 436         pthread_mutex_unlock(&protows->mutex);
 437         return rc;
 438 }
 439
 440 static int send_version_offer_1(struct afb_proto_ws *protows, uint8_t version)
 441 {
 442         int rc = -1;
 443         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 444
 445         if (writebuf_char(&wb, CHAR_FOR_VERSION_OFFER)
 446          && writebuf_uint32(&wb, WSAPI_IDENTIFIER)
 447          && writebuf_uint8(&wb, 1) /* offer one version */
 448          && writebuf_uint8(&wb, version))
 449                 rc = proto_write(protows, &wb);
 450         return rc;
 451 }
 452
 453 static int send_version_set(struct afb_proto_ws *protows, uint8_t version)
 454 {
 455         int rc = -1;
 456         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 457
 458         if (writebuf_char(&wb, CHAR_FOR_VERSION_SET)
 459          && writebuf_uint8(&wb, version))
 460                 rc = proto_write(protows, &wb);
 461         return rc;
 462 }
 463
 464 /******************* ws request part for server *****************/
 465
 466 void afb_proto_ws_call_addref(struct afb_proto_ws_call *call)
 467 {
 468         __atomic_add_fetch(&call->refcount, 1, __ATOMIC_RELAXED);
 469 }
 470
 471 void afb_proto_ws_call_unref(struct afb_proto_ws_call *call)
 472 {
 473         if (__atomic_sub_fetch(&call->refcount, 1, __ATOMIC_RELAXED))
 474                 return;
 475
 476         afb_proto_ws_unref(call->protows);
 477         free(call->buffer);
 478         free(call);
 479 }
 480
 481 int afb_proto_ws_call_reply(struct afb_proto_ws_call *call, struct json_object *obj, const char *error, const char *info)
 482 {
 483         int rc = -1;
 484         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 485         struct afb_proto_ws *protows = call->protows;
 486
 487         if (writebuf_char(&wb, CHAR_FOR_REPLY)
 488          && writebuf_uint16(&wb, call->callid)
 489          && writebuf_nullstring(&wb, error)
 490          && writebuf_nullstring(&wb, info)
 491          && writebuf_object(&wb, obj))
 492                 rc = proto_write(protows, &wb);
 493         return rc;
 494 }
 495
 496 int afb_proto_ws_call_subscribe(struct afb_proto_ws_call *call, uint16_t event_id)
 497 {
 498         int rc = -1;
 499         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 500         struct afb_proto_ws *protows = call->protows;
 501
 502         if (writebuf_char(&wb, CHAR_FOR_EVT_SUBSCRIBE)
 503          && writebuf_uint16(&wb, call->callid)
 504          && writebuf_uint16(&wb, event_id))
 505                 rc = proto_write(protows, &wb);
 506         return rc;
 507 }
 508
 509 int afb_proto_ws_call_unsubscribe(struct afb_proto_ws_call *call, uint16_t event_id)
 510 {
 511         int rc = -1;
 512         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 513         struct afb_proto_ws *protows = call->protows;
 514
 515         if (writebuf_char(&wb, CHAR_FOR_EVT_UNSUBSCRIBE)
 516          && writebuf_uint16(&wb, call->callid)
 517          && writebuf_uint16(&wb, event_id))
 518                 rc = proto_write(protows, &wb);
 519         return rc;
 520 }
 521
 522 /******************* client part **********************************/
 523
 524 /* search a memorized call */
 525 static struct client_call *client_call_search_locked(struct afb_proto_ws *protows, uint16_t callid)
 526 {
 527         struct client_call *call;
 528
 529         call = protows->calls;
 530         while (call != NULL && call->callid != callid)
 531                 call = call->next;
 532
 533         return call;
 534 }
 535
 536 static struct client_call *client_call_search_unlocked(struct afb_proto_ws *protows, uint16_t callid)
 537 {
 538         struct client_call *result;
 539
 540         pthread_mutex_lock(&protows->mutex);
 541         result = client_call_search_locked(protows, callid);
 542         pthread_mutex_unlock(&protows->mutex);
 543         return result;
 544 }
 545
 546 /* free and release the memorizing call */
 547 static void client_call_destroy(struct afb_proto_ws *protows, struct client_call *call)
 548 {
 549         struct client_call **prv;
 550
 551         pthread_mutex_lock(&protows->mutex);
 552         prv = &protows->calls;
 553         while (*prv != NULL) {
 554                 if (*prv == call) {
 555                         protows->idcount--;
 556                         *prv = call->next;
 557                         pthread_mutex_unlock(&protows->mutex);
 558                         free(call);
 559                         return;
 560                 }
 561                 prv = &(*prv)->next;
 562         }
 563         pthread_mutex_unlock(&protows->mutex);
 564 }
 565
 566 /* get event from the message */
 567 static int client_msg_call_get(struct afb_proto_ws *protows, struct readbuf *rb, struct client_call **call)
 568 {
 569         uint16_t callid;
 570
 571         /* get event data from the message */
 572         if (!readbuf_uint16(rb, &callid))
 573                 return 0;
 574
 575         /* get the call */
 576         *call = client_call_search_unlocked(protows, callid);
 577         return *call != NULL;
 578 }
 579
 580 /* adds an event */
 581 static void client_on_event_create(struct afb_proto_ws *protows, struct readbuf *rb)
 582 {
 583         const char *event_name;
 584         uint16_t event_id;
 585
 586         if (protows->client_itf->on_event_create
 587                         && readbuf_uint16(rb, &event_id)
 588                         && readbuf_string(rb, &event_name, NULL))
 589                 protows->client_itf->on_event_create(protows->closure, event_id, event_name);
 590         else
 591                 ERROR("Ignoring creation of event");
 592 }
 593
 594 /* removes an event */
 595 static void client_on_event_remove(struct afb_proto_ws *protows, struct readbuf *rb)
 596 {
 597         uint16_t event_id;
 598
 599         if (protows->client_itf->on_event_remove && readbuf_uint16(rb, &event_id))
 600                 protows->client_itf->on_event_remove(protows->closure, event_id);
 601         else
 602                 ERROR("Ignoring deletion of event");
 603 }
 604
 605 /* subscribes an event */
 606 static void client_on_event_subscribe(struct afb_proto_ws *protows, struct readbuf *rb)
 607 {
 608         uint16_t event_id;
 609         struct client_call *call;
 610
 611         if (protows->client_itf->on_event_subscribe && client_msg_call_get(protows, rb, &call) && readbuf_uint16(rb, &event_id))
 612                 protows->client_itf->on_event_subscribe(protows->closure, call->request, event_id);
 613         else
 614                 ERROR("Ignoring subscription to event");
 615 }
 616
 617 /* unsubscribes an event */
 618 static void client_on_event_unsubscribe(struct afb_proto_ws *protows, struct readbuf *rb)
 619 {
 620         uint16_t event_id;
 621         struct client_call *call;
 622
 623         if (protows->client_itf->on_event_unsubscribe && client_msg_call_get(protows, rb, &call) && readbuf_uint16(rb, &event_id))
 624                 protows->client_itf->on_event_unsubscribe(protows->closure, call->request, event_id);
 625         else
 626                 ERROR("Ignoring unsubscription to event");
 627 }
 628
 629 /* receives broadcasted events */
 630 static void client_on_event_broadcast(struct afb_proto_ws *protows, struct readbuf *rb)
 631 {
 632         const char *event_name, *uuid;
 633         uint8_t hop;
 634         struct json_object *object;
 635
 636         if (protows->client_itf->on_event_broadcast && readbuf_string(rb, &event_name, NULL) && readbuf_object(rb, &object) && (uuid = readbuf_get(rb, 16)) && readbuf_uint8(rb, &hop))
 637                 protows->client_itf->on_event_broadcast(protows->closure, event_name, object, (unsigned char*)uuid, hop);
 638         else
 639                 ERROR("Ignoring broadcast of event");
 640 }
 641
 642 /* pushs an event */
 643 static void client_on_event_push(struct afb_proto_ws *protows, struct readbuf *rb)
 644 {
 645         uint16_t event_id;
 646         struct json_object *object;
 647
 648         if (protows->client_itf->on_event_push && readbuf_uint16(rb, &event_id) && readbuf_object(rb, &object))
 649                 protows->client_itf->on_event_push(protows->closure, event_id, object);
 650         else
 651                 ERROR("Ignoring push of event");
 652 }
 653
 654 static void client_on_reply(struct afb_proto_ws *protows, struct readbuf *rb)
 655 {
 656         struct client_call *call;
 657         struct json_object *object;
 658         const char *error, *info;
 659
 660         if (!client_msg_call_get(protows, rb, &call))
 661                 return;
 662
 663         if (readbuf_nullstring(rb, &error, NULL) && readbuf_nullstring(rb, &info, NULL) && readbuf_object(rb, &object)) {
 664                 protows->client_itf->on_reply(protows->closure, call->request, object, error, info);
 665         } else {
 666                 protows->client_itf->on_reply(protows->closure, call->request, NULL, "proto-error", "can't process success");
 667         }
 668         client_call_destroy(protows, call);
 669 }
 670
 671 static void client_on_description(struct afb_proto_ws *protows, struct readbuf *rb)
 672 {
 673         uint32_t descid;
 674         struct client_describe *desc, **prv;
 675         struct json_object *object;
 676
 677         if (readbuf_uint32(rb, &descid)) {
 678                 pthread_mutex_lock(&protows->mutex);
 679                 prv = &protows->describes;
 680                 while ((desc = *prv) && desc->descid != descid)
 681                         prv = &desc->next;
 682                 if (!desc)
 683                         pthread_mutex_unlock(&protows->mutex);
 684                 else {
 685                         *prv = desc->next;
 686                         protows->idcount--;
 687                         pthread_mutex_unlock(&protows->mutex);
 688                         if (!readbuf_object(rb, &object))
 689                                 object = NULL;
 690                         desc->callback(desc->closure, object);
 691                         free(desc);
 692                 }
 693         }
 694 }
 695
 696 /* received a version set */
 697 static void client_on_version_set(struct afb_proto_ws *protows, struct readbuf *rb)
 698 {
 699         uint8_t version;
 700
 701         /* reads the descid */
 702         if (readbuf_uint8(rb, &version)
 703          && WSAPI_VERSION_MIN <= version
 704          && version <= WSAPI_VERSION_MAX) {
 705                 protows->version = version;
 706                 return;
 707         }
 708         afb_proto_ws_hangup(protows);
 709 }
 710
 711
 712 /* callback when receiving binary data */
 713 static void client_on_binary_job(int sig, void *closure)
 714 {
 715         struct binary *binary = closure;
 716
 717         if (!sig) {
 718                 switch (*binary->rb.head++) {
 719                 case CHAR_FOR_REPLY: /* reply */
 720                         client_on_reply(binary->protows, &binary->rb);
 721                         break;
 722                 case CHAR_FOR_EVT_BROADCAST: /* broadcast */
 723                         client_on_event_broadcast(binary->protows, &binary->rb);
 724                         break;
 725                 case CHAR_FOR_EVT_ADD: /* creates the event */
 726                         client_on_event_create(binary->protows, &binary->rb);
 727                         break;
 728                 case CHAR_FOR_EVT_DEL: /* removes the event */
 729                         client_on_event_remove(binary->protows, &binary->rb);
 730                         break;
 731                 case CHAR_FOR_EVT_PUSH: /* pushs the event */
 732                         client_on_event_push(binary->protows, &binary->rb);
 733                         break;
 734                 case CHAR_FOR_EVT_SUBSCRIBE: /* subscribe event for a request */
 735                         client_on_event_subscribe(binary->protows, &binary->rb);
 736                         break;
 737                 case CHAR_FOR_EVT_UNSUBSCRIBE: /* unsubscribe event for a request */
 738                         client_on_event_unsubscribe(binary->protows, &binary->rb);
 739                         break;
 740                 case CHAR_FOR_DESCRIPTION: /* description */
 741                         client_on_description(binary->protows, &binary->rb);
 742                         break;
 743                 case CHAR_FOR_VERSION_SET: /* set the protocol version */
 744                         client_on_version_set(binary->protows, &binary->rb);
 745                         break;
 746                 default: /* unexpected message */
 747                         /* TODO: close the connection */
 748                         break;
 749                 }
 750         }
 751         free(binary->rb.base);
 752         free(binary);
 753 }
 754
 755 /* callback when receiving binary data */
 756 static void client_on_binary(void *closure, char *data, size_t size)
 757 {
 758         struct afb_proto_ws *protows = closure;
 759
 760         queue_message_processing(protows, data, size, client_on_binary_job);
 761 }
 762
 763 static int client_send_cmd_id16_optstr(struct afb_proto_ws *protows, char order, uint16_t id, const char *value)
 764 {
 765         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 766         int rc = -1;
 767
 768         if (writebuf_char(&wb, order)
 769          && writebuf_uint16(&wb, id)
 770          && (!value || writebuf_string(&wb, value)))
 771                 rc = proto_write(protows, &wb);
 772         return rc;
 773 }
 774
 775 int afb_proto_ws_client_session_create(struct afb_proto_ws *protows, uint16_t sessionid, const char *sessionstr)
 776 {
 777         return client_send_cmd_id16_optstr(protows, CHAR_FOR_SESSION_ADD, sessionid, sessionstr);
 778 }
 779
 780 int afb_proto_ws_client_session_remove(struct afb_proto_ws *protows, uint16_t sessionid)
 781 {
 782         return client_send_cmd_id16_optstr(protows, CHAR_FOR_SESSION_DROP, sessionid, NULL);
 783 }
 784
 785 int afb_proto_ws_client_token_create(struct afb_proto_ws *protows, uint16_t tokenid, const char *tokenstr)
 786 {
 787         return client_send_cmd_id16_optstr(protows, CHAR_FOR_TOKEN_ADD, tokenid, tokenstr);
 788
 789 }
 790
 791 int afb_proto_ws_client_token_remove(struct afb_proto_ws *protows, uint16_t tokenid)
 792 {
 793         return client_send_cmd_id16_optstr(protows, CHAR_FOR_TOKEN_DROP, tokenid, NULL);
 794 }
 795
 796 int afb_proto_ws_client_event_unexpected(struct afb_proto_ws *protows, uint16_t eventid)
 797 {
 798         return client_send_cmd_id16_optstr(protows, CHAR_FOR_EVT_UNEXPECTED, eventid, NULL);
 799 }
 800
 801 int afb_proto_ws_client_call(
 802                 struct afb_proto_ws *protows,
 803                 const char *verb,
 804                 struct json_object *args,
 805                 uint16_t sessionid,
 806                 uint16_t tokenid,
 807                 void *request,
 808                 const char *user_creds
 809 )
 810 {
 811         int rc = -1;
 812         struct client_call *call;
 813         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 814         uint16_t id;
 815
 816         /* allocate call data */
 817         call = malloc(sizeof *call);
 818         if (call == NULL) {
 819                 errno = ENOMEM;
 820                 return -1;
 821         }
 822         call->request = request;
 823
 824         /* init call data */
 825         pthread_mutex_lock(&protows->mutex);
 826         if (protows->idcount >= ACTIVE_ID_MAX) {
 827                 pthread_mutex_unlock(&protows->mutex);
 828                 errno = EBUSY;
 829                 goto clean;
 830         }
 831         protows->idcount++;
 832         id = ++protows->genid;
 833         while(!id || client_call_search_locked(protows, id) != NULL)
 834                 id++;
 835         call->callid = protows->genid = id;
 836         call->next = protows->calls;
 837         protows->calls = call;
 838         pthread_mutex_unlock(&protows->mutex);
 839
 840         /* creates the call message */
 841         if (!writebuf_char(&wb, CHAR_FOR_CALL)
 842          || !writebuf_uint16(&wb, call->callid)
 843          || !writebuf_string(&wb, verb)
 844          || !writebuf_uint16(&wb, sessionid)
 845          || !writebuf_uint16(&wb, tokenid)
 846          || !writebuf_object(&wb, args)
 847          || !writebuf_nullstring(&wb, user_creds)) {
 848                 errno = EINVAL;
 849                 goto clean;
 850         }
 851
 852         /* send */
 853         rc = proto_write(protows, &wb);
 854         if (!rc)
 855                 goto end;
 856
 857 clean:
 858         client_call_destroy(protows, call);
 859 end:
 860         return rc;
 861 }
 862
 863 /* get the description */
 864 int afb_proto_ws_client_describe(struct afb_proto_ws *protows, void (*callback)(void*, struct json_object*), void *closure)
 865 {
 866         struct client_describe *desc, *d;
 867         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 868         uint16_t id;
 869
 870         desc = malloc(sizeof *desc);
 871         if (!desc) {
 872                 errno = ENOMEM;
 873                 goto error;
 874         }
 875
 876         /* fill in stack the description of the task */
 877         pthread_mutex_lock(&protows->mutex);
 878         if (protows->idcount >= ACTIVE_ID_MAX) {
 879                 errno = EBUSY;
 880                 goto busy;
 881         }
 882         protows->idcount++;
 883         id = ++protows->genid;
 884         d = protows->describes;
 885         while (d) {
 886                 if (id && d->descid != id)
 887                         d = d->next;
 888                 else {
 889                         id++;
 890                         d = protows->describes;
 891                 }
 892         }
 893         desc->descid = protows->genid = id;
 894         desc->callback = callback;
 895         desc->closure = closure;
 896         desc->next = protows->describes;
 897         protows->describes = desc;
 898         pthread_mutex_unlock(&protows->mutex);
 899
 900         /* send */
 901         if (!writebuf_char(&wb, CHAR_FOR_DESCRIBE)
 902          || !writebuf_uint16(&wb, desc->descid)) {
 903                  errno = EINVAL;
 904                  goto error2;
 905         }
 906
 907         if (proto_write(protows, &wb) == 0)
 908                 return 0;
 909
 910 error2:
 911         pthread_mutex_lock(&protows->mutex);
 912         d = protows->describes;
 913         if (d == desc)
 914                 protows->describes = desc->next;
 915         else {
 916                 while(d && d->next != desc)
 917                         d = d->next;
 918                 if (d)
 919                         d->next = desc->next;
 920         }
 921         protows->idcount--;
 922 busy:
 923         pthread_mutex_unlock(&protows->mutex);
 924         free(desc);
 925 error:
 926         /* TODO? callback(closure, NULL); */
 927         return -1;
 928 }
 929
 930 /******************* client description part for server *****************************/
 931
 932 /* on call, propagate it to the ws service */
 933 static void server_on_call(struct afb_proto_ws *protows, struct readbuf *rb)
 934 {
 935         struct afb_proto_ws_call *call;
 936         const char *verb, *user_creds;
 937         uint16_t callid, sessionid, tokenid;
 938         size_t lenverb;
 939         struct json_object *object;
 940
 941         afb_proto_ws_addref(protows);
 942
 943         /* reads the call message data */
 944         if (!readbuf_uint16(rb, &callid)
 945          || !readbuf_string(rb, &verb, &lenverb)
 946          || !readbuf_uint16(rb, &sessionid)
 947          || !readbuf_uint16(rb, &tokenid)
 948          || !readbuf_object(rb, &object)
 949          || !readbuf_nullstring(rb, &user_creds, NULL))
 950                 goto overflow;
 951
 952         /* create the request */
 953         call = malloc(sizeof *call);
 954         if (call == NULL)
 955                 goto out_of_memory;
 956
 957         call->protows = protows;
 958         call->callid = callid;
 959         call->refcount = 1;
 960         call->buffer = rb->base;
 961         rb->base = NULL; /* don't free the buffer */
 962
 963         protows->server_itf->on_call(protows->closure, call, verb, object, sessionid, tokenid, user_creds);
 964         return;
 965
 966 out_of_memory:
 967         json_object_put(object);
 968
 969 overflow:
 970         afb_proto_ws_unref(protows);
 971 }
 972
 973 static int server_send_description(struct afb_proto_ws *protows, uint32_t descid, struct json_object *descobj)
 974 {
 975         int rc = -1;
 976         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 977
 978         if (writebuf_char(&wb, CHAR_FOR_DESCRIPTION)
 979          && writebuf_uint32(&wb, descid)
 980          && writebuf_object(&wb, descobj))
 981                 rc = proto_write(protows, &wb);
 982         return rc;
 983 }
 984
 985 int afb_proto_ws_describe_put(struct afb_proto_ws_describe *describe, struct json_object *description)
 986 {
 987         int rc = server_send_description(describe->protows, describe->descid, description);
 988         afb_proto_ws_unref(describe->protows);
 989         free(describe);
 990         return rc;
 991 }
 992
 993 /* on describe, propagate it to the ws service */
 994 static void server_on_describe(struct afb_proto_ws *protows, struct readbuf *rb)
 995 {
 996         uint16_t descid;
 997         struct afb_proto_ws_describe *desc;
 998
 999         /* reads the descid */
1000         if (readbuf_uint16(rb, &descid)) {
1001                 if (protows->server_itf->on_describe) {
1002                         /* create asynchronous job */
1003                         desc = malloc(sizeof *desc);
1004                         if (desc) {
1005                                 desc->descid = descid;
1006                                 desc->protows = protows;
1007                                 afb_proto_ws_addref(protows);
1008                                 protows->server_itf->on_describe(protows->closure, desc);
1009                                 return;
1010                         }
1011                 }
1012                 server_send_description(protows, descid, NULL);
1013         }
1014 }
1015
1016 static void server_on_session_add(struct afb_proto_ws *protows, struct readbuf *rb)
1017 {
1018         uint16_t sessionid;
1019         const char *sessionstr;
1020
1021         if (readbuf_uint16(rb, &sessionid) && readbuf_string(rb, &sessionstr, NULL))
1022                 protows->server_itf->on_session_create(protows->closure, sessionid, sessionstr);
1023 }
1024
1025 static void server_on_session_drop(struct afb_proto_ws *protows, struct readbuf *rb)
1026 {
1027         uint16_t sessionid;
1028
1029         if (readbuf_uint16(rb, &sessionid))
1030                 protows->server_itf->on_session_remove(protows->closure, sessionid);
1031 }
1032
1033 static void server_on_token_add(struct afb_proto_ws *protows, struct readbuf *rb)
1034 {
1035         uint16_t tokenid;
1036         const char *tokenstr;
1037
1038         if (readbuf_uint16(rb, &tokenid) && readbuf_string(rb, &tokenstr, NULL))
1039                 protows->server_itf->on_token_create(protows->closure, tokenid, tokenstr);
1040 }
1041
1042 static void server_on_token_drop(struct afb_proto_ws *protows, struct readbuf *rb)
1043 {
1044         uint16_t tokenid;
1045
1046         if (readbuf_uint16(rb, &tokenid))
1047                 protows->server_itf->on_token_remove(protows->closure, tokenid);
1048 }
1049
1050 static void server_on_event_unexpected(struct afb_proto_ws *protows, struct readbuf *rb)
1051 {
1052         uint16_t eventid;
1053
1054         if (readbuf_uint16(rb, &eventid))
1055                 protows->server_itf->on_event_unexpected(protows->closure, eventid);
1056 }
1057
1058 /* on version offer */
1059 static void server_on_version_offer(struct afb_proto_ws *protows, struct readbuf *rb)
1060 {
1061         uint8_t count;
1062         uint8_t *versions;
1063         uint8_t version;
1064         uint8_t v;
1065         uint32_t id;
1066
1067         /* reads the descid */
1068         if (readbuf_uint32(rb, &id)
1069                 && id == WSAPI_IDENTIFIER
1070                 && readbuf_uint8(rb, &count)
1071                 && count > 0
1072                 && (versions = (uint8_t*)readbuf_get(rb, (uint32_t)count))) {
1073                 version = WSAPI_VERSION_UNSET;
1074                 while (count) {
1075                         v = versions[--count];
1076                         if (v >= WSAPI_VERSION_MIN
1077                          && v <= WSAPI_VERSION_MAX
1078                          && (version == WSAPI_VERSION_UNSET || version < v))
1079                                 version = v;
1080                 }
1081                 if (version != WSAPI_VERSION_UNSET) {
1082                         if (send_version_set(protows, version) >= 0) {
1083                                 protows->version = version;
1084                                 return;
1085                         }
1086                 }
1087         }
1088         afb_proto_ws_hangup(protows);
1089 }
1090
1091 /* callback when receiving binary data */
1092 static void server_on_binary_job(int sig, void *closure)
1093 {
1094         struct binary *binary = closure;
1095
1096         if (!sig) {
1097                 switch (*binary->rb.head++) {
1098                 case CHAR_FOR_CALL:
1099                         server_on_call(binary->protows, &binary->rb);
1100                         break;
1101                 case CHAR_FOR_DESCRIBE:
1102                         server_on_describe(binary->protows, &binary->rb);
1103                         break;
1104                 case CHAR_FOR_SESSION_ADD:
1105                         server_on_session_add(binary->protows, &binary->rb);
1106                         break;
1107                 case CHAR_FOR_SESSION_DROP:
1108                         server_on_session_drop(binary->protows, &binary->rb);
1109                         break;
1110                 case CHAR_FOR_TOKEN_ADD:
1111                         server_on_token_add(binary->protows, &binary->rb);
1112                         break;
1113                 case CHAR_FOR_TOKEN_DROP:
1114                         server_on_token_drop(binary->protows, &binary->rb);
1115                         break;
1116                 case CHAR_FOR_EVT_UNEXPECTED:
1117                         server_on_event_unexpected(binary->protows, &binary->rb);
1118                         break;
1119                 case CHAR_FOR_VERSION_OFFER:
1120                         server_on_version_offer(binary->protows, &binary->rb);
1121                         break;
1122                 default: /* unexpected message */
1123                         /* TODO: close the connection */
1124                         break;
1125                 }
1126         }
1127         free(binary->rb.base);
1128         free(binary);
1129 }
1130
1131 static void server_on_binary(void *closure, char *data, size_t size)
1132 {
1133         struct afb_proto_ws *protows = closure;
1134
1135         queue_message_processing(protows, data, size, server_on_binary_job);
1136 }
1137
1138 /******************* server part: manage events **********************************/
1139
1140 static int server_event_send(struct afb_proto_ws *protows, char order, uint16_t event_id, const char *event_name, struct json_object *data)
1141 {
1142         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
1143         int rc = -1;
1144
1145         if (writebuf_char(&wb, order)
1146          && writebuf_uint16(&wb, event_id)
1147          && (order != CHAR_FOR_EVT_ADD || writebuf_string(&wb, event_name))
1148          && (order != CHAR_FOR_EVT_PUSH || writebuf_object(&wb, data)))
1149                 rc = proto_write(protows, &wb);
1150         return rc;
1151 }
1152
1153 int afb_proto_ws_server_event_create(struct afb_proto_ws *protows, uint16_t event_id, const char *event_name)
1154 {
1155         return server_event_send(protows, CHAR_FOR_EVT_ADD, event_id, event_name, NULL);
1156 }
1157
1158 int afb_proto_ws_server_event_remove(struct afb_proto_ws *protows, uint16_t event_id)
1159 {
1160         return server_event_send(protows, CHAR_FOR_EVT_DEL, event_id, NULL, NULL);
1161 }
1162
1163 int afb_proto_ws_server_event_push(struct afb_proto_ws *protows, uint16_t event_id, struct json_object *data)
1164 {
1165         return server_event_send(protows, CHAR_FOR_EVT_PUSH, event_id, NULL, data);
1166 }
1167
1168 int afb_proto_ws_server_event_broadcast(struct afb_proto_ws *protows, const char *event_name, struct json_object *data, const unsigned char uuid[16], uint8_t hop)
1169 {
1170         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
1171         int rc = -1;
1172
1173         if (!hop)
1174                 return 0;
1175
1176         if (writebuf_char(&wb, CHAR_FOR_EVT_BROADCAST)
1177          && writebuf_string(&wb, event_name)
1178          && writebuf_object(&wb, data)
1179          && writebuf_put(&wb, uuid, 16)
1180          && writebuf_uint8(&wb, (uint8_t)(hop - 1)))
1181                 rc = proto_write(protows, &wb);
1182         return rc;
1183 }
1184
1185 /*****************************************************/
1186
1187 /* callback when receiving a hangup */
1188 static void on_hangup(void *closure)
1189 {
1190         struct afb_proto_ws *protows = closure;
1191         struct client_describe *cd, *ncd;
1192         struct client_call *call, *ncall;
1193         struct afb_ws *ws;
1194
1195         pthread_mutex_lock(&protows->mutex);
1196         ncd = protows->describes;
1197         protows->describes = NULL;
1198         ncall = protows->calls;
1199         protows->calls = NULL;
1200         ws = protows->ws;
1201         protows->ws = NULL;
1202         protows->idcount = 0;
1203         pthread_mutex_unlock(&protows->mutex);
1204
1205         while (ncall) {
1206                 call= ncall;
1207                 ncall = call->next;
1208                 protows->client_itf->on_reply(protows->closure, call->request, NULL, "disconnected", "server hung up");
1209                 free(call);
1210         }
1211
1212         while (ncd) {
1213                 cd= ncd;
1214                 ncd = cd->next;
1215                 cd->callback(cd->closure, NULL);
1216                 free(cd);
1217         }
1218
1219         if (ws) {
1220                 afb_ws_destroy(ws);
1221                 if (protows->on_hangup)
1222                         protows->on_hangup(protows->closure);
1223         }
1224 }
1225
1226 /*****************************************************/
1227
1228 static const struct afb_ws_itf proto_ws_client_ws_itf =
1229 {
1230         .on_close = NULL,
1231         .on_text = NULL,
1232         .on_binary = client_on_binary,
1233         .on_error = NULL,
1234         .on_hangup = on_hangup
1235 };
1236
1237 static const struct afb_ws_itf server_ws_itf =
1238 {
1239         .on_close = NULL,
1240         .on_text = NULL,
1241         .on_binary = server_on_binary,
1242         .on_error = NULL,
1243         .on_hangup = on_hangup
1244 };
1245
1246 /*****************************************************/
1247
1248 static struct afb_proto_ws *afb_proto_ws_create(struct fdev *fdev, const struct afb_proto_ws_server_itf *itfs, const struct afb_proto_ws_client_itf *itfc, void *closure, const struct afb_ws_itf *itf)
1249 {
1250         struct afb_proto_ws *protows;
1251
1252         protows = calloc(1, sizeof *protows);
1253         if (protows == NULL)
1254                 errno = ENOMEM;
1255         else {
1256                 fcntl(fdev_fd(fdev), F_SETFD, FD_CLOEXEC);
1257                 fcntl(fdev_fd(fdev), F_SETFL, O_NONBLOCK);
1258                 protows->ws = afb_ws_create(fdev, itf, protows);
1259                 if (protows->ws != NULL) {
1260                         protows->refcount = 1;
1261                         protows->version = WSAPI_VERSION_UNSET;
1262                         protows->closure = closure;
1263                         protows->server_itf = itfs;
1264                         protows->client_itf = itfc;
1265                         pthread_mutex_init(&protows->mutex, NULL);
1266                         return protows;
1267                 }
1268                 free(protows);
1269         }
1270         return NULL;
1271 }
1272
1273 struct afb_proto_ws *afb_proto_ws_create_client(struct fdev *fdev, const struct afb_proto_ws_client_itf *itf, void *closure)
1274 {
1275         struct afb_proto_ws *protows;
1276
1277         protows = afb_proto_ws_create(fdev, NULL, itf, closure, &proto_ws_client_ws_itf);
1278         if (protows) {
1279                 if (send_version_offer_1(protows, WSAPI_VERSION_1) != 0) {
1280                         afb_proto_ws_unref(protows);
1281                         protows = NULL;
1282                 }
1283         }
1284         return protows;
1285 }
1286
1287 struct afb_proto_ws *afb_proto_ws_create_server(struct fdev *fdev, const struct afb_proto_ws_server_itf *itf, void *closure)
1288 {
1289         return afb_proto_ws_create(fdev, itf, NULL, closure, &server_ws_itf);
1290 }
1291
1292 void afb_proto_ws_unref(struct afb_proto_ws *protows)
1293 {
1294         if (protows && !__atomic_sub_fetch(&protows->refcount, 1, __ATOMIC_RELAXED)) {
1295                 afb_proto_ws_hangup(protows);
1296                 pthread_mutex_destroy(&protows->mutex);
1297                 free(protows);
1298         }
1299 }
1300
1301 void afb_proto_ws_addref(struct afb_proto_ws *protows)
1302 {
1303         __atomic_add_fetch(&protows->refcount, 1, __ATOMIC_RELAXED);
1304 }
1305
1306 int afb_proto_ws_is_client(struct afb_proto_ws *protows)
1307 {
1308         return !!protows->client_itf;
1309 }
1310
1311 int afb_proto_ws_is_server(struct afb_proto_ws *protows)
1312 {
1313         return !!protows->server_itf;
1314 }
1315
1316 void afb_proto_ws_hangup(struct afb_proto_ws *protows)
1317 {
1318         if (protows->ws)
1319                 afb_ws_hangup(protows->ws);
1320 }
1321
1322 void afb_proto_ws_on_hangup(struct afb_proto_ws *protows, void (*on_hangup)(void *closure))
1323 {
1324         protows->on_hangup = on_hangup;
1325 }
1326
1327 void afb_proto_ws_set_queuing(struct afb_proto_ws *protows, int (*queuing)(struct afb_proto_ws*, void (*)(int,void*), void*))
1328 {
1329         protows->queuing = queuing;
1330 }