src/afb-proto-ws.c

   1 /*
   2  * Copyright (C) 2015-2019 "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 */
  71 /************** constants for protocol definition *************************/
  72
  73 #define CHAR_FOR_CALL             'K'   /* client -> server */
  74 #define CHAR_FOR_REPLY            'k'   /* server -> client */
  75 #define CHAR_FOR_EVT_BROADCAST    'B'   /* server -> client */
  76 #define CHAR_FOR_EVT_ADD          'E'   /* server -> client */
  77 #define CHAR_FOR_EVT_DEL          'e'   /* server -> client */
  78 #define CHAR_FOR_EVT_PUSH         'P'   /* server -> client */
  79 #define CHAR_FOR_EVT_SUBSCRIBE    'X'   /* server -> client */
  80 #define CHAR_FOR_EVT_UNSUBSCRIBE  'x'   /* server -> client */
  81 #define CHAR_FOR_DESCRIBE         'D'   /* client -> server */
  82 #define CHAR_FOR_DESCRIPTION      'd'   /* server -> client */
  83 #define CHAR_FOR_TOKEN_ADD        'T'   /* client -> server */
  84 #define CHAR_FOR_TOKEN_DROP       't'   /* client -> server */
  85 #define CHAR_FOR_SESSION_ADD      'S'   /* client -> server */
  86 #define CHAR_FOR_SESSION_DROP     's'   /* client -> server */
  87 #define CHAR_FOR_VERSION_OFFER    'V'   /* client -> server */
  88 #define CHAR_FOR_VERSION_SET      'v'   /* server -> client */
  89
  90 /******************* manage versions *****************************/
  91
  92 #define WSAPI_IDENTIFIER        02723012011  /* wsapi: 23.19.1.16.9 */
  93
  94 #define WSAPI_VERSION_UNSET     0
  95 #define WSAPI_VERSION_1         1
  96
  97 #define WSAPI_VERSION_MIN       WSAPI_VERSION_1
  98 #define WSAPI_VERSION_MAX       WSAPI_VERSION_1
  99
 100 /******************* maximum count of ids ***********************/
 101
 102 #define ACTIVE_ID_MAX           4095
 103
 104 /******************* handling calls *****************************/
 105
 106 /*
 107  * structure for recording calls on client side
 108  */
 109 struct client_call {
 110         struct client_call *next;       /* the next call */
 111         void *request;                  /* the request closure */
 112         uint16_t callid;                /* the message identifier */
 113 };
 114
 115 /*
 116  * structure for a ws request
 117  */
 118 struct afb_proto_ws_call {
 119         struct afb_proto_ws *protows;   /* the client of the request */
 120         char *buffer;                   /* the incoming buffer */
 121         uint16_t refcount;              /* reference count */
 122         uint16_t callid;                /* the incoming request callid */
 123 };
 124
 125 /*
 126  * structure for recording describe requests
 127  */
 128 struct client_describe
 129 {
 130         struct client_describe *next;
 131         void (*callback)(void*, struct json_object*);
 132         void *closure;
 133         uint16_t descid;
 134 };
 135
 136 /*
 137  * structure for jobs of describing
 138  */
 139 struct afb_proto_ws_describe
 140 {
 141         struct afb_proto_ws *protows;
 142         uint16_t descid;
 143 };
 144
 145 /******************* proto description for client or servers ******************/
 146
 147 struct afb_proto_ws
 148 {
 149         /* count of references */
 150         uint16_t refcount;
 151
 152         /* id generator */
 153         uint16_t genid;
 154
 155         /* count actives ids */
 156         uint16_t idcount;
 157
 158         /* version */
 159         uint8_t version;
 160
 161         /* resource control */
 162         pthread_mutex_t mutex;
 163
 164         /* websocket */
 165         struct afb_ws *ws;
 166
 167         /* the client closure */
 168         void *closure;
 169
 170         /* the client side interface */
 171         const struct afb_proto_ws_client_itf *client_itf;
 172
 173         /* the server side interface */
 174         const struct afb_proto_ws_server_itf *server_itf;
 175
 176         /* emitted calls (client side) */
 177         struct client_call *calls;
 178
 179         /* pending description (client side) */
 180         struct client_describe *describes;
 181
 182         /* on hangup callback */
 183         void (*on_hangup)(void *closure);
 184
 185         /* queuing facility for processing messages */
 186         int (*queuing)(struct afb_proto_ws *proto, void (*process)(int s, void *c), void *closure);
 187 };
 188
 189 /******************* streaming objects **********************************/
 190
 191 #define WRITEBUF_COUNT_MAX      32
 192 #define WRITEBUF_BUFSZ          (WRITEBUF_COUNT_MAX * sizeof(uint32_t))
 193
 194 struct writebuf
 195 {
 196         int iovcount, bufcount;
 197         struct iovec iovec[WRITEBUF_COUNT_MAX];
 198         char buf[WRITEBUF_BUFSZ];
 199 };
 200
 201 struct readbuf
 202 {
 203         char *base, *head, *end;
 204 };
 205
 206 struct binary
 207 {
 208         struct afb_proto_ws *protows;
 209         struct readbuf rb;
 210 };
 211
 212 /******************* serialization part **********************************/
 213
 214 static char *readbuf_get(struct readbuf *rb, uint32_t length)
 215 {
 216         char *before = rb->head;
 217         char *after = before + length;
 218         if (after > rb->end)
 219                 return 0;
 220         rb->head = after;
 221         return before;
 222 }
 223
 224 static int readbuf_getat(struct readbuf *rb, void *to, uint32_t length)
 225 {
 226         char *head = readbuf_get(rb, length);
 227         if (!head)
 228                 return 0;
 229         memcpy(to, head, length);
 230         return 1;
 231 }
 232
 233 __attribute__((unused))
 234 static int readbuf_char(struct readbuf *rb, char *value)
 235 {
 236         return readbuf_getat(rb, value, sizeof *value);
 237 }
 238
 239 static int readbuf_uint32(struct readbuf *rb, uint32_t *value)
 240 {
 241         int r = readbuf_getat(rb, value, sizeof *value);
 242         if (r)
 243                 *value = le32toh(*value);
 244         return r;
 245 }
 246
 247 static int readbuf_uint16(struct readbuf *rb, uint16_t *value)
 248 {
 249         int r = readbuf_getat(rb, value, sizeof *value);
 250         if (r)
 251                 *value = le16toh(*value);
 252         return r;
 253 }
 254
 255 static int readbuf_uint8(struct readbuf *rb, uint8_t *value)
 256 {
 257         return readbuf_getat(rb, value, sizeof *value);
 258 }
 259
 260 static int _readbuf_string_(struct readbuf *rb, const char **value, size_t *length, int nulok)
 261 {
 262         uint32_t len;
 263         if (!readbuf_uint32(rb, &len))
 264                 return 0;
 265         if (!len) {
 266                 if (!nulok)
 267                         return 0;
 268                 *value = NULL;
 269                 if (length)
 270                         *length = 0;
 271                 return 1;
 272         }
 273         if (length)
 274                 *length = (size_t)(len - 1);
 275         return (*value = readbuf_get(rb, len)) != NULL &&  rb->head[-1] == 0;
 276 }
 277
 278
 279 static int readbuf_string(struct readbuf *rb, const char **value, size_t *length)
 280 {
 281         return _readbuf_string_(rb, value, length, 0);
 282 }
 283
 284 static int readbuf_nullstring(struct readbuf *rb, const char **value, size_t *length)
 285 {
 286         return _readbuf_string_(rb, value, length, 1);
 287 }
 288
 289 static int readbuf_object(struct readbuf *rb, struct json_object **object)
 290 {
 291         const char *string;
 292         struct json_object *o;
 293         enum json_tokener_error jerr;
 294         int rc = readbuf_string(rb, &string, NULL);
 295         if (rc) {
 296                 o = json_tokener_parse_verbose(string, &jerr);
 297                 if (jerr != json_tokener_success)
 298                         o = json_object_new_string(string);
 299                 *object = o;
 300         }
 301         return rc;
 302 }
 303
 304 static int writebuf_put(struct writebuf *wb, const void *value, size_t length)
 305 {
 306         int i = wb->iovcount;
 307         if (i == WRITEBUF_COUNT_MAX)
 308                 return 0;
 309         wb->iovec[i].iov_base = (void*)value;
 310         wb->iovec[i].iov_len = length;
 311         wb->iovcount = i + 1;
 312         return 1;
 313 }
 314
 315 static int writebuf_putbuf(struct writebuf *wb, const void *value, int length)
 316 {
 317         char *p;
 318         int i = wb->iovcount, n = wb->bufcount, nafter;
 319
 320         /* check enough length */
 321         nafter = n + length;
 322         if (nafter > WRITEBUF_BUFSZ)
 323                 return 0;
 324
 325         /* get where to store */
 326         p = &wb->buf[n];
 327         if (i && p == (((char*)wb->iovec[i - 1].iov_base) + wb->iovec[i - 1].iov_len))
 328                 /* increase previous iovec */
 329                 wb->iovec[i - 1].iov_len += (size_t)length;
 330         else if (i == WRITEBUF_COUNT_MAX)
 331                 /* no more iovec */
 332                 return 0;
 333         else {
 334                 /* new iovec */
 335                 wb->iovec[i].iov_base = p;
 336                 wb->iovec[i].iov_len = (size_t)length;
 337                 wb->iovcount = i + 1;
 338         }
 339         /* store now */
 340         memcpy(p, value, (size_t)length);
 341         wb->bufcount = nafter;
 342         return 1;
 343 }
 344
 345 __attribute__((unused))
 346 static int writebuf_char(struct writebuf *wb, char value)
 347 {
 348         return writebuf_putbuf(wb, &value, 1);
 349 }
 350
 351 static int writebuf_uint32(struct writebuf *wb, uint32_t value)
 352 {
 353         value = htole32(value);
 354         return writebuf_putbuf(wb, &value, (int)sizeof value);
 355 }
 356
 357 static int writebuf_uint16(struct writebuf *wb, uint16_t value)
 358 {
 359         value = htole16(value);
 360         return writebuf_putbuf(wb, &value, (int)sizeof value);
 361 }
 362
 363 static int writebuf_uint8(struct writebuf *wb, uint8_t value)
 364 {
 365         return writebuf_putbuf(wb, &value, (int)sizeof value);
 366 }
 367
 368 static int writebuf_string_length(struct writebuf *wb, const char *value, size_t length)
 369 {
 370         uint32_t len = (uint32_t)++length;
 371         return (size_t)len == length && len && writebuf_uint32(wb, len) && writebuf_put(wb, value, length);
 372 }
 373
 374 static int writebuf_string(struct writebuf *wb, const char *value)
 375 {
 376         return writebuf_string_length(wb, value, strlen(value));
 377 }
 378
 379 static int writebuf_nullstring(struct writebuf *wb, const char *value)
 380 {
 381         return value ? writebuf_string_length(wb, value, strlen(value)) : writebuf_uint32(wb, 0);
 382 }
 383
 384 static int writebuf_object(struct writebuf *wb, struct json_object *object)
 385 {
 386         const char *string = json_object_to_json_string_ext(object, JSON_C_TO_STRING_PLAIN);
 387         return string != NULL && writebuf_string(wb, string);
 388 }
 389
 390 /******************* queuing of messages *****************/
 391
 392 /* queue the processing of the received message (except if size=0 cause it's not a valid message) */
 393 static void queue_message_processing(struct afb_proto_ws *protows, char *data, size_t size, void (*processing)(int,void*))
 394 {
 395         struct binary *binary;
 396
 397         if (size) {
 398                 binary = malloc(sizeof *binary);
 399                 if (!binary) {
 400                         /* TODO process the problem */
 401                         errno = ENOMEM;
 402                 } else {
 403                         binary->protows = protows;
 404                         binary->rb.base = data;
 405                         binary->rb.head = data;
 406                         binary->rb.end = data + size;
 407                         if (!protows->queuing
 408                          || protows->queuing(protows, processing, binary) < 0)
 409                                 processing(0, binary);
 410                         return;
 411                 }
 412         }
 413         free(data);
 414 }
 415
 416 /******************* sending messages *****************/
 417
 418 static int proto_write(struct afb_proto_ws *protows, struct writebuf *wb)
 419 {
 420         int rc;
 421         struct afb_ws *ws;
 422
 423         pthread_mutex_lock(&protows->mutex);
 424         ws = protows->ws;
 425         if (ws == NULL) {
 426                 errno = EPIPE;
 427                 rc = -1;
 428         } else {
 429                 rc = afb_ws_binary_v(ws, wb->iovec, wb->iovcount);
 430                 if (rc > 0)
 431                         rc = 0;
 432         }
 433         pthread_mutex_unlock(&protows->mutex);
 434         return rc;
 435 }
 436
 437 static int send_version_offer_1(struct afb_proto_ws *protows, uint8_t version)
 438 {
 439         int rc = -1;
 440         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 441
 442         if (writebuf_char(&wb, CHAR_FOR_VERSION_OFFER)
 443          && writebuf_uint32(&wb, WSAPI_IDENTIFIER)
 444          && writebuf_uint8(&wb, 1) /* offer one version */
 445          && writebuf_uint8(&wb, version))
 446                 rc = proto_write(protows, &wb);
 447         return rc;
 448 }
 449
 450 static int send_version_set(struct afb_proto_ws *protows, uint8_t version)
 451 {
 452         int rc = -1;
 453         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 454
 455         if (writebuf_char(&wb, CHAR_FOR_VERSION_SET)
 456          && writebuf_uint8(&wb, version))
 457                 rc = proto_write(protows, &wb);
 458         return rc;
 459 }
 460
 461 /******************* ws request part for server *****************/
 462
 463 void afb_proto_ws_call_addref(struct afb_proto_ws_call *call)
 464 {
 465         __atomic_add_fetch(&call->refcount, 1, __ATOMIC_RELAXED);
 466 }
 467
 468 void afb_proto_ws_call_unref(struct afb_proto_ws_call *call)
 469 {
 470         if (__atomic_sub_fetch(&call->refcount, 1, __ATOMIC_RELAXED))
 471                 return;
 472
 473         afb_proto_ws_unref(call->protows);
 474         free(call->buffer);
 475         free(call);
 476 }
 477
 478 int afb_proto_ws_call_reply(struct afb_proto_ws_call *call, struct json_object *obj, const char *error, const char *info)
 479 {
 480         int rc = -1;
 481         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 482         struct afb_proto_ws *protows = call->protows;
 483
 484         if (writebuf_char(&wb, CHAR_FOR_REPLY)
 485          && writebuf_uint16(&wb, call->callid)
 486          && writebuf_nullstring(&wb, error)
 487          && writebuf_nullstring(&wb, info)
 488          && writebuf_object(&wb, obj))
 489                 rc = proto_write(protows, &wb);
 490         return rc;
 491 }
 492
 493 int afb_proto_ws_call_subscribe(struct afb_proto_ws_call *call, uint16_t event_id)
 494 {
 495         int rc = -1;
 496         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 497         struct afb_proto_ws *protows = call->protows;
 498
 499         if (writebuf_char(&wb, CHAR_FOR_EVT_SUBSCRIBE)
 500          && writebuf_uint16(&wb, call->callid)
 501          && writebuf_uint16(&wb, event_id))
 502                 rc = proto_write(protows, &wb);
 503         return rc;
 504 }
 505
 506 int afb_proto_ws_call_unsubscribe(struct afb_proto_ws_call *call, uint16_t event_id)
 507 {
 508         int rc = -1;
 509         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 510         struct afb_proto_ws *protows = call->protows;
 511
 512         if (writebuf_char(&wb, CHAR_FOR_EVT_UNSUBSCRIBE)
 513          && writebuf_uint16(&wb, call->callid)
 514          && writebuf_uint16(&wb, event_id))
 515                 rc = proto_write(protows, &wb);
 516         return rc;
 517 }
 518
 519 /******************* client part **********************************/
 520
 521 /* search a memorized call */
 522 static struct client_call *client_call_search_locked(struct afb_proto_ws *protows, uint16_t callid)
 523 {
 524         struct client_call *call;
 525
 526         call = protows->calls;
 527         while (call != NULL && call->callid != callid)
 528                 call = call->next;
 529
 530         return call;
 531 }
 532
 533 static struct client_call *client_call_search_unlocked(struct afb_proto_ws *protows, uint16_t callid)
 534 {
 535         struct client_call *result;
 536
 537         pthread_mutex_lock(&protows->mutex);
 538         result = client_call_search_locked(protows, callid);
 539         pthread_mutex_unlock(&protows->mutex);
 540         return result;
 541 }
 542
 543 /* free and release the memorizing call */
 544 static void client_call_destroy(struct afb_proto_ws *protows, struct client_call *call)
 545 {
 546         struct client_call **prv;
 547
 548         pthread_mutex_lock(&protows->mutex);
 549         prv = &protows->calls;
 550         while (*prv != NULL) {
 551                 if (*prv == call) {
 552                         protows->idcount--;
 553                         *prv = call->next;
 554                         pthread_mutex_unlock(&protows->mutex);
 555                         free(call);
 556                         return;
 557                 }
 558                 prv = &(*prv)->next;
 559         }
 560         pthread_mutex_unlock(&protows->mutex);
 561 }
 562
 563 /* get event from the message */
 564 static int client_msg_call_get(struct afb_proto_ws *protows, struct readbuf *rb, struct client_call **call)
 565 {
 566         uint16_t callid;
 567
 568         /* get event data from the message */
 569         if (!readbuf_uint16(rb, &callid))
 570                 return 0;
 571
 572         /* get the call */
 573         *call = client_call_search_unlocked(protows, callid);
 574         return *call != NULL;
 575 }
 576
 577 /* adds an event */
 578 static void client_on_event_create(struct afb_proto_ws *protows, struct readbuf *rb)
 579 {
 580         const char *event_name;
 581         uint16_t event_id;
 582
 583         if (protows->client_itf->on_event_create
 584                         && readbuf_uint16(rb, &event_id)
 585                         && readbuf_string(rb, &event_name, NULL))
 586                 protows->client_itf->on_event_create(protows->closure, event_id, event_name);
 587         else
 588                 ERROR("Ignoring creation of event");
 589 }
 590
 591 /* removes an event */
 592 static void client_on_event_remove(struct afb_proto_ws *protows, struct readbuf *rb)
 593 {
 594         uint16_t event_id;
 595
 596         if (protows->client_itf->on_event_remove && readbuf_uint16(rb, &event_id))
 597                 protows->client_itf->on_event_remove(protows->closure, event_id);
 598         else
 599                 ERROR("Ignoring deletion of event");
 600 }
 601
 602 /* subscribes an event */
 603 static void client_on_event_subscribe(struct afb_proto_ws *protows, struct readbuf *rb)
 604 {
 605         uint16_t event_id;
 606         struct client_call *call;
 607
 608         if (protows->client_itf->on_event_subscribe && client_msg_call_get(protows, rb, &call) && readbuf_uint16(rb, &event_id))
 609                 protows->client_itf->on_event_subscribe(protows->closure, call->request, event_id);
 610         else
 611                 ERROR("Ignoring subscription to event");
 612 }
 613
 614 /* unsubscribes an event */
 615 static void client_on_event_unsubscribe(struct afb_proto_ws *protows, struct readbuf *rb)
 616 {
 617         uint16_t event_id;
 618         struct client_call *call;
 619
 620         if (protows->client_itf->on_event_unsubscribe && client_msg_call_get(protows, rb, &call) && readbuf_uint16(rb, &event_id))
 621                 protows->client_itf->on_event_unsubscribe(protows->closure, call->request, event_id);
 622         else
 623                 ERROR("Ignoring unsubscription to event");
 624 }
 625
 626 /* receives broadcasted events */
 627 static void client_on_event_broadcast(struct afb_proto_ws *protows, struct readbuf *rb)
 628 {
 629         const char *event_name, *uuid;
 630         uint8_t hop;
 631         struct json_object *object;
 632
 633         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))
 634                 protows->client_itf->on_event_broadcast(protows->closure, event_name, object, (unsigned char*)uuid, hop);
 635         else
 636                 ERROR("Ignoring broadcast of event");
 637 }
 638
 639 /* pushs an event */
 640 static void client_on_event_push(struct afb_proto_ws *protows, struct readbuf *rb)
 641 {
 642         uint16_t event_id;
 643         struct json_object *object;
 644
 645         if (protows->client_itf->on_event_push && readbuf_uint16(rb, &event_id) && readbuf_object(rb, &object))
 646                 protows->client_itf->on_event_push(protows->closure, event_id, object);
 647         else
 648                 ERROR("Ignoring push of event");
 649 }
 650
 651 static void client_on_reply(struct afb_proto_ws *protows, struct readbuf *rb)
 652 {
 653         struct client_call *call;
 654         struct json_object *object;
 655         const char *error, *info;
 656
 657         if (!client_msg_call_get(protows, rb, &call))
 658                 return;
 659
 660         if (readbuf_nullstring(rb, &error, NULL) && readbuf_nullstring(rb, &info, NULL) && readbuf_object(rb, &object)) {
 661                 protows->client_itf->on_reply(protows->closure, call->request, object, error, info);
 662         } else {
 663                 protows->client_itf->on_reply(protows->closure, call->request, NULL, "proto-error", "can't process success");
 664         }
 665         client_call_destroy(protows, call);
 666 }
 667
 668 static void client_on_description(struct afb_proto_ws *protows, struct readbuf *rb)
 669 {
 670         uint32_t descid;
 671         struct client_describe *desc, **prv;
 672         struct json_object *object;
 673
 674         if (readbuf_uint32(rb, &descid)) {
 675                 pthread_mutex_lock(&protows->mutex);
 676                 prv = &protows->describes;
 677                 while ((desc = *prv) && desc->descid != descid)
 678                         prv = &desc->next;
 679                 if (!desc)
 680                         pthread_mutex_unlock(&protows->mutex);
 681                 else {
 682                         *prv = desc->next;
 683                         protows->idcount--;
 684                         pthread_mutex_unlock(&protows->mutex);
 685                         if (!readbuf_object(rb, &object))
 686                                 object = NULL;
 687                         desc->callback(desc->closure, object);
 688                         free(desc);
 689                 }
 690         }
 691 }
 692
 693 /* received a version set */
 694 static void client_on_version_set(struct afb_proto_ws *protows, struct readbuf *rb)
 695 {
 696         uint8_t version;
 697
 698         /* reads the descid */
 699         if (readbuf_uint8(rb, &version)
 700          && WSAPI_VERSION_MIN <= version
 701          && version <= WSAPI_VERSION_MAX) {
 702                 protows->version = version;
 703                 return;
 704         }
 705         afb_proto_ws_hangup(protows);
 706 }
 707
 708
 709 /* callback when receiving binary data */
 710 static void client_on_binary_job(int sig, void *closure)
 711 {
 712         struct binary *binary = closure;
 713
 714         if (!sig) {
 715                 switch (*binary->rb.head++) {
 716                 case CHAR_FOR_REPLY: /* reply */
 717                         client_on_reply(binary->protows, &binary->rb);
 718                         break;
 719                 case CHAR_FOR_EVT_BROADCAST: /* broadcast */
 720                         client_on_event_broadcast(binary->protows, &binary->rb);
 721                         break;
 722                 case CHAR_FOR_EVT_ADD: /* creates the event */
 723                         client_on_event_create(binary->protows, &binary->rb);
 724                         break;
 725                 case CHAR_FOR_EVT_DEL: /* removes the event */
 726                         client_on_event_remove(binary->protows, &binary->rb);
 727                         break;
 728                 case CHAR_FOR_EVT_PUSH: /* pushs the event */
 729                         client_on_event_push(binary->protows, &binary->rb);
 730                         break;
 731                 case CHAR_FOR_EVT_SUBSCRIBE: /* subscribe event for a request */
 732                         client_on_event_subscribe(binary->protows, &binary->rb);
 733                         break;
 734                 case CHAR_FOR_EVT_UNSUBSCRIBE: /* unsubscribe event for a request */
 735                         client_on_event_unsubscribe(binary->protows, &binary->rb);
 736                         break;
 737                 case CHAR_FOR_DESCRIPTION: /* description */
 738                         client_on_description(binary->protows, &binary->rb);
 739                         break;
 740                 case CHAR_FOR_VERSION_SET: /* set the protocol version */
 741                         client_on_version_set(binary->protows, &binary->rb);
 742                         break;
 743                 default: /* unexpected message */
 744                         /* TODO: close the connection */
 745                         break;
 746                 }
 747         }
 748         free(binary->rb.base);
 749         free(binary);
 750 }
 751
 752 /* callback when receiving binary data */
 753 static void client_on_binary(void *closure, char *data, size_t size)
 754 {
 755         struct afb_proto_ws *protows = closure;
 756
 757         queue_message_processing(protows, data, size, client_on_binary_job);
 758 }
 759
 760 static int client_send_cmd_id16_optstr(struct afb_proto_ws *protows, char order, uint16_t id, const char *value)
 761 {
 762         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 763         int rc = -1;
 764
 765         if (writebuf_char(&wb, order)
 766          && writebuf_uint16(&wb, id)
 767          && (!value || writebuf_string(&wb, value)))
 768                 rc = proto_write(protows, &wb);
 769         return rc;
 770 }
 771
 772 int afb_proto_ws_client_session_create(struct afb_proto_ws *protows, uint16_t sessionid, const char *sessionstr)
 773 {
 774         return client_send_cmd_id16_optstr(protows, CHAR_FOR_SESSION_ADD, sessionid, sessionstr);
 775 }
 776
 777 int afb_proto_ws_client_session_remove(struct afb_proto_ws *protows, uint16_t sessionid)
 778 {
 779         return client_send_cmd_id16_optstr(protows, CHAR_FOR_SESSION_DROP, sessionid, NULL);
 780 }
 781
 782 int afb_proto_ws_client_token_create(struct afb_proto_ws *protows, uint16_t tokenid, const char *tokenstr)
 783 {
 784         return client_send_cmd_id16_optstr(protows, CHAR_FOR_TOKEN_ADD, tokenid, tokenstr);
 785
 786 }
 787
 788 int afb_proto_ws_client_token_remove(struct afb_proto_ws *protows, uint16_t tokenid)
 789 {
 790         return client_send_cmd_id16_optstr(protows, CHAR_FOR_TOKEN_DROP, tokenid, NULL);
 791 }
 792
 793 int afb_proto_ws_client_call(
 794                 struct afb_proto_ws *protows,
 795                 const char *verb,
 796                 struct json_object *args,
 797                 uint16_t sessionid,
 798                 uint16_t tokenid,
 799                 void *request,
 800                 const char *user_creds
 801 )
 802 {
 803         int rc = -1;
 804         struct client_call *call;
 805         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 806         uint16_t id;
 807
 808         /* allocate call data */
 809         call = malloc(sizeof *call);
 810         if (call == NULL) {
 811                 errno = ENOMEM;
 812                 return -1;
 813         }
 814         call->request = request;
 815
 816         /* init call data */
 817         pthread_mutex_lock(&protows->mutex);
 818         if (protows->idcount >= ACTIVE_ID_MAX) {
 819                 pthread_mutex_unlock(&protows->mutex);
 820                 errno = EBUSY;
 821                 goto clean;
 822         }
 823         protows->idcount++;
 824         id = ++protows->genid;
 825         while(!id || client_call_search_locked(protows, id) != NULL)
 826                 id++;
 827         call->callid = protows->genid = id;
 828         call->next = protows->calls;
 829         protows->calls = call;
 830         pthread_mutex_unlock(&protows->mutex);
 831
 832         /* creates the call message */
 833         if (!writebuf_char(&wb, CHAR_FOR_CALL)
 834          || !writebuf_uint16(&wb, call->callid)
 835          || !writebuf_string(&wb, verb)
 836          || !writebuf_uint16(&wb, sessionid)
 837          || !writebuf_uint16(&wb, tokenid)
 838          || !writebuf_object(&wb, args)
 839          || !writebuf_nullstring(&wb, user_creds)) {
 840                 errno = EINVAL;
 841                 goto clean;
 842         }
 843
 844         /* send */
 845         rc = proto_write(protows, &wb);
 846         if (!rc)
 847                 goto end;
 848
 849 clean:
 850         client_call_destroy(protows, call);
 851 end:
 852         return rc;
 853 }
 854
 855 /* get the description */
 856 int afb_proto_ws_client_describe(struct afb_proto_ws *protows, void (*callback)(void*, struct json_object*), void *closure)
 857 {
 858         struct client_describe *desc, *d;
 859         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 860         uint16_t id;
 861
 862         desc = malloc(sizeof *desc);
 863         if (!desc) {
 864                 errno = ENOMEM;
 865                 goto error;
 866         }
 867
 868         /* fill in stack the description of the task */
 869         pthread_mutex_lock(&protows->mutex);
 870         if (protows->idcount >= ACTIVE_ID_MAX) {
 871                 errno = EBUSY;
 872                 goto busy;
 873         }
 874         protows->idcount++;
 875         id = ++protows->genid;
 876         d = protows->describes;
 877         while (d) {
 878                 if (id && d->descid != id)
 879                         d = d->next;
 880                 else {
 881                         id++;
 882                         d = protows->describes;
 883                 }
 884         }
 885         desc->descid = protows->genid = id;
 886         desc->callback = callback;
 887         desc->closure = closure;
 888         desc->next = protows->describes;
 889         protows->describes = desc;
 890         pthread_mutex_unlock(&protows->mutex);
 891
 892         /* send */
 893         if (!writebuf_char(&wb, CHAR_FOR_DESCRIBE)
 894          || !writebuf_uint16(&wb, desc->descid)) {
 895                  errno = EINVAL;
 896                  goto error2;
 897         }
 898
 899         if (proto_write(protows, &wb) == 0)
 900                 return 0;
 901
 902 error2:
 903         pthread_mutex_lock(&protows->mutex);
 904         d = protows->describes;
 905         if (d == desc)
 906                 protows->describes = desc->next;
 907         else {
 908                 while(d && d->next != desc)
 909                         d = d->next;
 910                 if (d)
 911                         d->next = desc->next;
 912         }
 913         protows->idcount--;
 914 busy:
 915         pthread_mutex_unlock(&protows->mutex);
 916         free(desc);
 917 error:
 918         /* TODO? callback(closure, NULL); */
 919         return -1;
 920 }
 921
 922 /******************* client description part for server *****************************/
 923
 924 /* on call, propagate it to the ws service */
 925 static void server_on_call(struct afb_proto_ws *protows, struct readbuf *rb)
 926 {
 927         struct afb_proto_ws_call *call;
 928         const char *verb, *user_creds;
 929         uint16_t callid, sessionid, tokenid;
 930         size_t lenverb;
 931         struct json_object *object;
 932
 933         afb_proto_ws_addref(protows);
 934
 935         /* reads the call message data */
 936         if (!readbuf_uint16(rb, &callid)
 937          || !readbuf_string(rb, &verb, &lenverb)
 938          || !readbuf_uint16(rb, &sessionid)
 939          || !readbuf_uint16(rb, &tokenid)
 940          || !readbuf_object(rb, &object)
 941          || !readbuf_nullstring(rb, &user_creds, NULL))
 942                 goto overflow;
 943
 944         /* create the request */
 945         call = malloc(sizeof *call);
 946         if (call == NULL)
 947                 goto out_of_memory;
 948
 949         call->protows = protows;
 950         call->callid = callid;
 951         call->refcount = 1;
 952         call->buffer = rb->base;
 953         rb->base = NULL; /* don't free the buffer */
 954
 955         protows->server_itf->on_call(protows->closure, call, verb, object, sessionid, tokenid, user_creds);
 956         return;
 957
 958 out_of_memory:
 959         json_object_put(object);
 960
 961 overflow:
 962         afb_proto_ws_unref(protows);
 963 }
 964
 965 static int server_send_description(struct afb_proto_ws *protows, uint32_t descid, struct json_object *descobj)
 966 {
 967         int rc = -1;
 968         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 969
 970         if (writebuf_char(&wb, CHAR_FOR_DESCRIPTION)
 971          && writebuf_uint32(&wb, descid)
 972          && writebuf_object(&wb, descobj))
 973                 rc = proto_write(protows, &wb);
 974         return rc;
 975 }
 976
 977 int afb_proto_ws_describe_put(struct afb_proto_ws_describe *describe, struct json_object *description)
 978 {
 979         int rc = server_send_description(describe->protows, describe->descid, description);
 980         afb_proto_ws_unref(describe->protows);
 981         free(describe);
 982         return rc;
 983 }
 984
 985 /* on describe, propagate it to the ws service */
 986 static void server_on_describe(struct afb_proto_ws *protows, struct readbuf *rb)
 987 {
 988         uint16_t descid;
 989         struct afb_proto_ws_describe *desc;
 990
 991         /* reads the descid */
 992         if (readbuf_uint16(rb, &descid)) {
 993                 if (protows->server_itf->on_describe) {
 994                         /* create asynchronous job */
 995                         desc = malloc(sizeof *desc);
 996                         if (desc) {
 997                                 desc->descid = descid;
 998                                 desc->protows = protows;
 999                                 afb_proto_ws_addref(protows);
1000                                 protows->server_itf->on_describe(protows->closure, desc);
1001                                 return;
1002                         }
1003                 }
1004                 server_send_description(protows, descid, NULL);
1005         }
1006 }
1007
1008 static void server_on_session_add(struct afb_proto_ws *protows, struct readbuf *rb)
1009 {
1010         uint16_t sessionid;
1011         const char *sessionstr;
1012
1013         if (readbuf_uint16(rb, &sessionid) && readbuf_string(rb, &sessionstr, NULL))
1014                 protows->server_itf->on_session_create(protows->closure, sessionid, sessionstr);
1015 }
1016
1017 static void server_on_session_drop(struct afb_proto_ws *protows, struct readbuf *rb)
1018 {
1019         uint16_t sessionid;
1020
1021         if (readbuf_uint16(rb, &sessionid))
1022                 protows->server_itf->on_session_remove(protows->closure, sessionid);
1023 }
1024
1025 static void server_on_token_add(struct afb_proto_ws *protows, struct readbuf *rb)
1026 {
1027         uint16_t tokenid;
1028         const char *tokenstr;
1029
1030         if (readbuf_uint16(rb, &tokenid) && readbuf_string(rb, &tokenstr, NULL))
1031                 protows->server_itf->on_token_create(protows->closure, tokenid, tokenstr);
1032 }
1033
1034 static void server_on_token_drop(struct afb_proto_ws *protows, struct readbuf *rb)
1035 {
1036         uint16_t tokenid;
1037
1038         if (readbuf_uint16(rb, &tokenid))
1039                 protows->server_itf->on_token_remove(protows->closure, tokenid);
1040 }
1041
1042 /* on version offer */
1043 static void server_on_version_offer(struct afb_proto_ws *protows, struct readbuf *rb)
1044 {
1045         uint8_t count;
1046         uint8_t *versions;
1047         uint8_t version;
1048         uint8_t v;
1049         uint32_t id;
1050
1051         /* reads the descid */
1052         if (readbuf_uint32(rb, &id)
1053                 && id == WSAPI_IDENTIFIER
1054                 && readbuf_uint8(rb, &count)
1055                 && count > 0
1056                 && (versions = (uint8_t*)readbuf_get(rb, (uint32_t)count))) {
1057                 version = WSAPI_VERSION_UNSET;
1058                 while (count) {
1059                         v = versions[--count];
1060                         if (v >= WSAPI_VERSION_MIN
1061                          && v <= WSAPI_VERSION_MAX
1062                          && (version == WSAPI_VERSION_UNSET || version < v))
1063                                 version = v;
1064                 }
1065                 if (version != WSAPI_VERSION_UNSET) {
1066                         if (send_version_set(protows, version) >= 0) {
1067                                 protows->version = version;
1068                                 return;
1069                         }
1070                 }
1071         }
1072         afb_proto_ws_hangup(protows);
1073 }
1074
1075 /* callback when receiving binary data */
1076 static void server_on_binary_job(int sig, void *closure)
1077 {
1078         struct binary *binary = closure;
1079
1080         if (!sig) {
1081                 switch (*binary->rb.head++) {
1082                 case CHAR_FOR_CALL:
1083                         server_on_call(binary->protows, &binary->rb);
1084                         break;
1085                 case CHAR_FOR_DESCRIBE:
1086                         server_on_describe(binary->protows, &binary->rb);
1087                         break;
1088                 case CHAR_FOR_SESSION_ADD:
1089                         server_on_session_add(binary->protows, &binary->rb);
1090                         break;
1091                 case CHAR_FOR_SESSION_DROP:
1092                         server_on_session_drop(binary->protows, &binary->rb);
1093                         break;
1094                 case CHAR_FOR_TOKEN_ADD:
1095                         server_on_token_add(binary->protows, &binary->rb);
1096                         break;
1097                 case CHAR_FOR_TOKEN_DROP:
1098                         server_on_token_drop(binary->protows, &binary->rb);
1099                         break;
1100                 case CHAR_FOR_VERSION_OFFER:
1101                         server_on_version_offer(binary->protows, &binary->rb);
1102                         break;
1103                 default: /* unexpected message */
1104                         /* TODO: close the connection */
1105                         break;
1106                 }
1107         }
1108         free(binary->rb.base);
1109         free(binary);
1110 }
1111
1112 static void server_on_binary(void *closure, char *data, size_t size)
1113 {
1114         struct afb_proto_ws *protows = closure;
1115
1116         queue_message_processing(protows, data, size, server_on_binary_job);
1117 }
1118
1119 /******************* server part: manage events **********************************/
1120
1121 static int server_event_send(struct afb_proto_ws *protows, char order, uint16_t event_id, const char *event_name, struct json_object *data)
1122 {
1123         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
1124         int rc = -1;
1125
1126         if (writebuf_char(&wb, order)
1127          && writebuf_uint16(&wb, event_id)
1128          && (order != CHAR_FOR_EVT_ADD || writebuf_string(&wb, event_name))
1129          && (order != CHAR_FOR_EVT_PUSH || writebuf_object(&wb, data)))
1130                 rc = proto_write(protows, &wb);
1131         return rc;
1132 }
1133
1134 int afb_proto_ws_server_event_create(struct afb_proto_ws *protows, uint16_t event_id, const char *event_name)
1135 {
1136         return server_event_send(protows, CHAR_FOR_EVT_ADD, event_id, event_name, NULL);
1137 }
1138
1139 int afb_proto_ws_server_event_remove(struct afb_proto_ws *protows, uint16_t event_id)
1140 {
1141         return server_event_send(protows, CHAR_FOR_EVT_DEL, event_id, NULL, NULL);
1142 }
1143
1144 int afb_proto_ws_server_event_push(struct afb_proto_ws *protows, uint16_t event_id, struct json_object *data)
1145 {
1146         return server_event_send(protows, CHAR_FOR_EVT_PUSH, event_id, NULL, data);
1147 }
1148
1149 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)
1150 {
1151         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
1152         int rc = -1;
1153
1154         if (!hop)
1155                 return 0;
1156
1157         if (writebuf_char(&wb, CHAR_FOR_EVT_BROADCAST)
1158          && writebuf_string(&wb, event_name)
1159          && writebuf_object(&wb, data)
1160          && writebuf_put(&wb, uuid, 16)
1161          && writebuf_uint8(&wb, (uint8_t)(hop - 1)))
1162                 rc = proto_write(protows, &wb);
1163         return rc;
1164 }
1165
1166 /*****************************************************/
1167
1168 /* callback when receiving a hangup */
1169 static void on_hangup(void *closure)
1170 {
1171         struct afb_proto_ws *protows = closure;
1172         struct client_describe *cd, *ncd;
1173         struct client_call *call, *ncall;
1174         struct afb_ws *ws;
1175
1176         pthread_mutex_lock(&protows->mutex);
1177         ncd = protows->describes;
1178         protows->describes = NULL;
1179         ncall = protows->calls;
1180         protows->calls = NULL;
1181         ws = protows->ws;
1182         protows->ws = NULL;
1183         protows->idcount = 0;
1184         pthread_mutex_unlock(&protows->mutex);
1185
1186         while (ncall) {
1187                 call= ncall;
1188                 ncall = call->next;
1189                 protows->client_itf->on_reply(protows->closure, call->request, NULL, "disconnected", "server hung up");
1190                 free(call);
1191         }
1192
1193         while (ncd) {
1194                 cd= ncd;
1195                 ncd = cd->next;
1196                 cd->callback(cd->closure, NULL);
1197                 free(cd);
1198         }
1199
1200         if (ws) {
1201                 afb_ws_destroy(ws);
1202                 if (protows->on_hangup)
1203                         protows->on_hangup(protows->closure);
1204         }
1205 }
1206
1207 /*****************************************************/
1208
1209 static const struct afb_ws_itf proto_ws_client_ws_itf =
1210 {
1211         .on_close = NULL,
1212         .on_text = NULL,
1213         .on_binary = client_on_binary,
1214         .on_error = NULL,
1215         .on_hangup = on_hangup
1216 };
1217
1218 static const struct afb_ws_itf server_ws_itf =
1219 {
1220         .on_close = NULL,
1221         .on_text = NULL,
1222         .on_binary = server_on_binary,
1223         .on_error = NULL,
1224         .on_hangup = on_hangup
1225 };
1226
1227 /*****************************************************/
1228
1229 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)
1230 {
1231         struct afb_proto_ws *protows;
1232
1233         protows = calloc(1, sizeof *protows);
1234         if (protows == NULL)
1235                 errno = ENOMEM;
1236         else {
1237                 fcntl(fdev_fd(fdev), F_SETFD, FD_CLOEXEC);
1238                 fcntl(fdev_fd(fdev), F_SETFL, O_NONBLOCK);
1239                 protows->ws = afb_ws_create(fdev, itf, protows);
1240                 if (protows->ws != NULL) {
1241                         protows->refcount = 1;
1242                         protows->version = WSAPI_VERSION_UNSET;
1243                         protows->closure = closure;
1244                         protows->server_itf = itfs;
1245                         protows->client_itf = itfc;
1246                         pthread_mutex_init(&protows->mutex, NULL);
1247                         return protows;
1248                 }
1249                 free(protows);
1250         }
1251         return NULL;
1252 }
1253
1254 struct afb_proto_ws *afb_proto_ws_create_client(struct fdev *fdev, const struct afb_proto_ws_client_itf *itf, void *closure)
1255 {
1256         struct afb_proto_ws *protows;
1257
1258         protows = afb_proto_ws_create(fdev, NULL, itf, closure, &proto_ws_client_ws_itf);
1259         if (protows) {
1260                 if (send_version_offer_1(protows, WSAPI_VERSION_1) != 0) {
1261                         afb_proto_ws_unref(protows);
1262                         protows = NULL;
1263                 }
1264         }
1265         return protows;
1266 }
1267
1268 struct afb_proto_ws *afb_proto_ws_create_server(struct fdev *fdev, const struct afb_proto_ws_server_itf *itf, void *closure)
1269 {
1270         return afb_proto_ws_create(fdev, itf, NULL, closure, &server_ws_itf);
1271 }
1272
1273 void afb_proto_ws_unref(struct afb_proto_ws *protows)
1274 {
1275         if (protows && !__atomic_sub_fetch(&protows->refcount, 1, __ATOMIC_RELAXED)) {
1276                 afb_proto_ws_hangup(protows);
1277                 pthread_mutex_destroy(&protows->mutex);
1278                 free(protows);
1279         }
1280 }
1281
1282 void afb_proto_ws_addref(struct afb_proto_ws *protows)
1283 {
1284         __atomic_add_fetch(&protows->refcount, 1, __ATOMIC_RELAXED);
1285 }
1286
1287 int afb_proto_ws_is_client(struct afb_proto_ws *protows)
1288 {
1289         return !!protows->client_itf;
1290 }
1291
1292 int afb_proto_ws_is_server(struct afb_proto_ws *protows)
1293 {
1294         return !!protows->server_itf;
1295 }
1296
1297 void afb_proto_ws_hangup(struct afb_proto_ws *protows)
1298 {
1299         if (protows->ws)
1300                 afb_ws_hangup(protows->ws);
1301 }
1302
1303 void afb_proto_ws_on_hangup(struct afb_proto_ws *protows, void (*on_hangup)(void *closure))
1304 {
1305         protows->on_hangup = on_hangup;
1306 }
1307
1308 void afb_proto_ws_set_queuing(struct afb_proto_ws *protows, int (*queuing)(struct afb_proto_ws*, void (*)(int,void*), void*))
1309 {
1310         protows->queuing = queuing;
1311 }