src/lib/raop.c

   1 /**
   2  *  Copyright (C) 2011-2012  Juho Vähä-Herttua
   3  *
   4  *  This library is free software; you can redistribute it and/or
   5  *  modify it under the terms of the GNU Lesser General Public
   6  *  License as published by the Free Software Foundation; either
   7  *  version 2.1 of the License, or (at your option) any later version.
   8  *
   9  *  This library is distributed in the hope that it will be useful,
  10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  *  Lesser General Public License for more details.
  13  */
  14
  15 #include <stdlib.h>
  16 #include <stdio.h>
  17 #include <string.h>
  18 #include <assert.h>
  19
  20 #include "raop.h"
  21 #include "raop_rtp.h"
  22 #include "rsakey.h"
  23 #include "digest.h"
  24 #include "httpd.h"
  25 #include "sdp.h"
  26
  27 #include "global.h"
  28 #include "utils.h"
  29 #include "netutils.h"
  30 #include "logger.h"
  31 #include "compat.h"
  32
  33 /* Actually 345 bytes for 2048-bit key */
  34 #define MAX_SIGNATURE_LEN 512
  35
  36 /* Let's just decide on some length */
  37 #define MAX_PASSWORD_LEN 64
  38
  39 /* MD5 as hex fits here */
  40 #define MAX_NONCE_LEN 32
  41
  42 struct raop_s {
  43         /* Callbacks for audio */
  44         raop_callbacks_t callbacks;
  45
  46         /* Logger instance */
  47         logger_t *logger;
  48
  49         /* HTTP daemon and RSA key */
  50         httpd_t *httpd;
  51         rsakey_t *rsakey;
  52
  53         /* Hardware address information */
  54         unsigned char hwaddr[MAX_HWADDR_LEN];
  55         int hwaddrlen;
  56
  57         /* Password information */
  58         char password[MAX_PASSWORD_LEN+1];
  59 };
  60
  61 struct raop_conn_s {
  62         raop_t *raop;
  63         raop_rtp_t *raop_rtp;
  64
  65         unsigned char *local;
  66         int locallen;
  67
  68         unsigned char *remote;
  69         int remotelen;
  70
  71         char nonce[MAX_NONCE_LEN+1];
  72 };
  73 typedef struct raop_conn_s raop_conn_t;
  74
  75 static void *
  76 conn_init(void *opaque, unsigned char *local, int locallen, unsigned char *remote, int remotelen)
  77 {
  78         raop_conn_t *conn;
  79
  80         conn = calloc(1, sizeof(raop_conn_t));
  81         if (!conn) {
  82                 return NULL;
  83         }
  84         conn->raop = opaque;
  85         conn->raop_rtp = NULL;
  86
  87         if (locallen == 4) {
  88                 logger_log(conn->raop->logger, LOGGER_INFO,
  89                            "Local: %d.%d.%d.%d",
  90                            local[0], local[1], local[2], local[3]);
  91         } else if (locallen == 16) {
  92                 logger_log(conn->raop->logger, LOGGER_INFO,
  93                            "Local: %02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x",
  94                            local[0], local[1], local[2], local[3], local[4], local[5], local[6], local[7],
  95                            local[8], local[9], local[10], local[11], local[12], local[13], local[14], local[15]);
  96         }
  97         if (remotelen == 4) {
  98                 logger_log(conn->raop->logger, LOGGER_INFO,
  99                            "Remote: %d.%d.%d.%d",
 100                            remote[0], remote[1], remote[2], remote[3]);
 101         } else if (remotelen == 16) {
 102                 logger_log(conn->raop->logger, LOGGER_INFO,
 103                            "Remote: %02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x",
 104                            remote[0], remote[1], remote[2], remote[3], remote[4], remote[5], remote[6], remote[7],
 105                            remote[8], remote[9], remote[10], remote[11], remote[12], remote[13], remote[14], remote[15]);
 106         }
 107
 108         conn->local = malloc(locallen);
 109         assert(conn->local);
 110         memcpy(conn->local, local, locallen);
 111
 112         conn->remote = malloc(remotelen);
 113         assert(conn->remote);
 114         memcpy(conn->remote, remote, remotelen);
 115
 116         conn->locallen = locallen;
 117         conn->remotelen = remotelen;
 118
 119         digest_generate_nonce(conn->nonce, sizeof(conn->nonce));
 120         return conn;
 121 }
 122
 123 static void
 124 conn_request(void *ptr, http_request_t *request, http_response_t **response)
 125 {
 126         raop_conn_t *conn = ptr;
 127         raop_t *raop = conn->raop;
 128
 129         http_response_t *res;
 130         const char *method;
 131         const char *cseq;
 132         const char *challenge;
 133         int require_auth = 0;
 134
 135         method = http_request_get_method(request);
 136         cseq = http_request_get_header(request, "CSeq");
 137         if (!method || !cseq) {
 138                 return;
 139         }
 140
 141         res = http_response_init("RTSP/1.0", 200, "OK");
 142         if (strlen(raop->password)) {
 143                 const char *authorization;
 144
 145                 authorization = http_request_get_header(request, "Authorization");
 146                 if (authorization) {
 147                         logger_log(conn->raop->logger, LOGGER_DEBUG, "Our nonce: %s", conn->nonce);
 148                         logger_log(conn->raop->logger, LOGGER_DEBUG, "Authorization: %s", authorization);
 149                 }
 150                 if (!digest_is_valid("AppleTV", raop->password, conn->nonce, method, http_request_get_url(request), authorization)) {
 151                         char *authstr;
 152                         int authstrlen;
 153
 154                         /* Allocate the authenticate string */
 155                         authstrlen = sizeof("Digest realm=\"AppleTV\", nonce=\"\"") + sizeof(conn->nonce) + 1;
 156                         authstr = malloc(authstrlen);
 157
 158                         /* Concatenate the authenticate string */
 159                         memset(authstr, 0, authstrlen);
 160                         strcat(authstr, "Digest realm=\"AppleTV\", nonce=\"");
 161                         strcat(authstr, conn->nonce);
 162                         strcat(authstr, "\"");
 163
 164                         /* Construct a new response */
 165                         require_auth = 1;
 166                         http_response_destroy(res);
 167                         res = http_response_init("RTSP/1.0", 401, "Unauthorized");
 168                         http_response_add_header(res, "WWW-Authenticate", authstr);
 169                         free(authstr);
 170                 } else {
 171                         logger_log(conn->raop->logger, LOGGER_DEBUG, "AUTHENTICATION SUCCESS!");
 172                 }
 173         }
 174
 175         http_response_add_header(res, "CSeq", cseq);
 176         http_response_add_header(res, "Apple-Jack-Status", "connected; type=analog");
 177
 178         challenge = http_request_get_header(request, "Apple-Challenge");
 179         if (!require_auth && challenge) {
 180                 char signature[MAX_SIGNATURE_LEN];
 181
 182                 memset(signature, 0, sizeof(signature));
 183                 rsakey_sign(raop->rsakey, signature, sizeof(signature), challenge,
 184                             conn->local, conn->locallen, raop->hwaddr, raop->hwaddrlen);
 185                 http_response_add_header(res, "Apple-Response", signature);
 186
 187                 logger_log(conn->raop->logger, LOGGER_DEBUG, "Got challenge: %s", challenge);
 188                 logger_log(conn->raop->logger, LOGGER_DEBUG, "Got response: %s", signature);
 189         }
 190
 191         if (require_auth) {
 192                 /* Do nothing in case of authentication request */
 193         } else if (!strcmp(method, "OPTIONS")) {
 194                 http_response_add_header(res, "Public", "ANNOUNCE, SETUP, RECORD, PAUSE, FLUSH, TEARDOWN, OPTIONS, GET_PARAMETER, SET_PARAMETER");
 195         } else if (!strcmp(method, "ANNOUNCE")) {
 196                 const char *data;
 197                 int datalen;
 198
 199                 unsigned char aeskey[16];
 200                 unsigned char aesiv[16];
 201                 int aeskeylen, aesivlen;
 202
 203                 data = http_request_get_data(request, &datalen);
 204                 if (data) {
 205                         sdp_t *sdp;
 206                         const char *remotestr, *rtpmapstr, *fmtpstr, *aeskeystr, *aesivstr;
 207
 208                         sdp = sdp_init(data, datalen);
 209                         remotestr = sdp_get_connection(sdp);
 210                         rtpmapstr = sdp_get_rtpmap(sdp);
 211                         fmtpstr = sdp_get_fmtp(sdp);
 212                         aeskeystr = sdp_get_rsaaeskey(sdp);
 213                         aesivstr = sdp_get_aesiv(sdp);
 214
 215                         logger_log(conn->raop->logger, LOGGER_DEBUG, "connection: %s", remotestr);
 216                         logger_log(conn->raop->logger, LOGGER_DEBUG, "rtpmap: %s", rtpmapstr);
 217                         logger_log(conn->raop->logger, LOGGER_DEBUG, "fmtp: %s", fmtpstr);
 218                         logger_log(conn->raop->logger, LOGGER_DEBUG, "rsaaeskey: %s", aeskeystr);
 219                         logger_log(conn->raop->logger, LOGGER_DEBUG, "aesiv: %s", aesivstr);
 220
 221                         aeskeylen = rsakey_decrypt(raop->rsakey, aeskey, sizeof(aeskey), aeskeystr);
 222                         aesivlen = rsakey_parseiv(raop->rsakey, aesiv, sizeof(aesiv), aesivstr);
 223                         logger_log(conn->raop->logger, LOGGER_DEBUG, "aeskeylen: %d", aeskeylen);
 224                         logger_log(conn->raop->logger, LOGGER_DEBUG, "aesivlen: %d", aesivlen);
 225
 226                         if (conn->raop_rtp) {
 227                                 /* This should never happen */
 228                                 raop_rtp_destroy(conn->raop_rtp);
 229                                 conn->raop_rtp = NULL;
 230                         }
 231                         conn->raop_rtp = raop_rtp_init(raop->logger, &raop->callbacks, remotestr, rtpmapstr, fmtpstr, aeskey, aesiv);
 232                         sdp_destroy(sdp);
 233                 }
 234         } else if (!strcmp(method, "SETUP")) {
 235                 unsigned short remote_cport=0, remote_tport=0;
 236                 unsigned short cport=0, tport=0, dport=0;
 237                 const char *transport;
 238                 char buffer[1024];
 239                 int use_udp;
 240
 241                 transport = http_request_get_header(request, "Transport");
 242                 assert(transport);
 243
 244                 logger_log(conn->raop->logger, LOGGER_INFO, "Transport: %s", transport);
 245                 use_udp = strncmp(transport, "RTP/AVP/TCP", 11);
 246                 if (use_udp) {
 247                         char *original, *current, *tmpstr;
 248
 249                         current = original = strdup(transport);
 250                         if (original) {
 251                                 while ((tmpstr = utils_strsep(&current, ";")) != NULL) {
 252                                         unsigned short value;
 253                                         int ret;
 254
 255                                         ret = sscanf(tmpstr, "control_port=%hu", &value);
 256                                         if (ret == 1) {
 257                                                 logger_log(conn->raop->logger, LOGGER_DEBUG, "Found remote control port: %hu", value);
 258                                                 remote_cport = value;
 259                                         }
 260                                         ret = sscanf(tmpstr, "timing_port=%hu", &value);
 261                                         if (ret == 1) {
 262                                                 logger_log(conn->raop->logger, LOGGER_DEBUG, "Found remote timing port: %hu", value);
 263                                                 remote_tport = value;
 264                                         }
 265                                 }
 266                         }
 267                         free(original);
 268                 }
 269                 raop_rtp_start(conn->raop_rtp, use_udp, remote_cport, remote_tport, &cport, &tport, &dport);
 270
 271                 memset(buffer, 0, sizeof(buffer));
 272                 if (use_udp) {
 273                         snprintf(buffer, sizeof(buffer)-1,
 274                                  "RTP/AVP/UDP;unicast;mode=record;timing_port=%hu;events;control_port=%hu;server_port=%hu",
 275                                  tport, cport, dport);
 276                 } else {
 277                         snprintf(buffer, sizeof(buffer)-1,
 278                                  "RTP/AVP/TCP;unicast;interleaved=0-1;mode=record;server_port=%u",
 279                                  dport);
 280                 }
 281                 logger_log(conn->raop->logger, LOGGER_INFO, "Responding with %s", buffer);
 282                 http_response_add_header(res, "Transport", buffer);
 283                 http_response_add_header(res, "Session", "DEADBEEF");
 284         } else if (!strcmp(method, "SET_PARAMETER")) {
 285                 const char *content_type;
 286                 const char *data;
 287                 int datalen;
 288
 289                 content_type = http_request_get_header(request, "Content-Type");
 290                 data = http_request_get_data(request, &datalen);
 291                 if (!strcmp(content_type, "text/parameters")) {
 292                         char *datastr;
 293                         datastr = calloc(1, datalen+1);
 294                         if (data && datastr && conn->raop_rtp) {
 295                                 memcpy(datastr, data, datalen);
 296                                 if (!strncmp(datastr, "volume: ", 8)) {
 297                                         float vol = 0.0;
 298                                         sscanf(datastr+8, "%f", &vol);
 299                                         raop_rtp_set_volume(conn->raop_rtp, vol);
 300                                 }
 301                         }
 302                         free(datastr);
 303                 } else if (!strcmp(content_type, "image/jpeg")) {
 304                         logger_log(conn->raop->logger, LOGGER_INFO, "Got image data of %d bytes", datalen);
 305                         raop_rtp_set_coverart(conn->raop_rtp, data, datalen);
 306                 } else if (!strcmp(content_type, "application/x-dmap-tagged")) {
 307                         logger_log(conn->raop->logger, LOGGER_INFO, "Got metadata of %d bytes", datalen);
 308                         raop_rtp_set_metadata(conn->raop_rtp, data, datalen);
 309                 }
 310         } else if (!strcmp(method, "FLUSH")) {
 311                 const char *rtpinfo;
 312                 int next_seq = -1;
 313
 314                 rtpinfo = http_request_get_header(request, "RTP-Info");
 315                 if (rtpinfo) {
 316                         logger_log(conn->raop->logger, LOGGER_INFO, "Flush with RTP-Info: %s", rtpinfo);
 317                         if (!strncmp(rtpinfo, "seq=", 4)) {
 318                                 next_seq = strtol(rtpinfo+4, NULL, 10);
 319                         }
 320                 }
 321                 if (conn->raop_rtp) {
 322                         raop_rtp_flush(conn->raop_rtp, next_seq);
 323                 }
 324         } else if (!strcmp(method, "TEARDOWN")) {
 325                 http_response_add_header(res, "Connection", "close");
 326                 if (conn->raop_rtp) {
 327                         /* Destroy our RTP session */
 328                         raop_rtp_stop(conn->raop_rtp);
 329                         raop_rtp_destroy(conn->raop_rtp);
 330                         conn->raop_rtp = NULL;
 331                 }
 332         }
 333         http_response_finish(res, NULL, 0);
 334
 335         logger_log(conn->raop->logger, LOGGER_DEBUG, "Got request %s with URL %s", method, http_request_get_url(request));
 336         *response = res;
 337 }
 338
 339 static void
 340 conn_destroy(void *ptr)
 341 {
 342         raop_conn_t *conn = ptr;
 343
 344         if (conn->raop_rtp) {
 345                 /* This is done in case TEARDOWN was not called */
 346                 raop_rtp_destroy(conn->raop_rtp);
 347         }
 348         free(conn->local);
 349         free(conn->remote);
 350         free(conn);
 351 }
 352
 353 raop_t *
 354 raop_init(int max_clients, raop_callbacks_t *callbacks, const char *pemkey, int *error)
 355 {
 356         raop_t *raop;
 357         httpd_t *httpd;
 358         rsakey_t *rsakey;
 359         httpd_callbacks_t httpd_cbs;
 360
 361         assert(callbacks);
 362         assert(max_clients > 0);
 363         assert(max_clients < 100);
 364         assert(pemkey);
 365
 366         /* Initialize the network */
 367         if (netutils_init() < 0) {
 368                 return NULL;
 369         }
 370
 371         /* Validate the callbacks structure */
 372         if (!callbacks->audio_init ||
 373             !callbacks->audio_process ||
 374             !callbacks->audio_destroy) {
 375                 return NULL;
 376         }
 377
 378         /* Allocate the raop_t structure */
 379         raop = calloc(1, sizeof(raop_t));
 380         if (!raop) {
 381                 return NULL;
 382         }
 383
 384         /* Initialize the logger */
 385         raop->logger = logger_init();
 386
 387         /* Set HTTP callbacks to our handlers */
 388         memset(&httpd_cbs, 0, sizeof(httpd_cbs));
 389         httpd_cbs.opaque = raop;
 390         httpd_cbs.conn_init = &conn_init;
 391         httpd_cbs.conn_request = &conn_request;
 392         httpd_cbs.conn_destroy = &conn_destroy;
 393
 394         /* Initialize the http daemon */
 395         httpd = httpd_init(raop->logger, &httpd_cbs, max_clients);
 396         if (!httpd) {
 397                 free(raop);
 398                 return NULL;
 399         }
 400
 401         /* Copy callbacks structure */
 402         memcpy(&raop->callbacks, callbacks, sizeof(raop_callbacks_t));
 403
 404         /* Initialize RSA key handler */
 405         rsakey = rsakey_init_pem(pemkey);
 406         if (!rsakey) {
 407                 free(httpd);
 408                 free(raop);
 409                 return NULL;
 410         }
 411
 412         raop->httpd = httpd;
 413         raop->rsakey = rsakey;
 414
 415         return raop;
 416 }
 417
 418 raop_t *
 419 raop_init_from_keyfile(int max_clients, raop_callbacks_t *callbacks, const char *keyfile, int *error)
 420 {
 421         raop_t *raop;
 422         char *pemstr;
 423
 424         if (utils_read_file(&pemstr, keyfile) < 0) {
 425                 return NULL;
 426         }
 427         raop = raop_init(max_clients, callbacks, pemstr, error);
 428         free(pemstr);
 429         return raop;
 430 }
 431
 432 void
 433 raop_destroy(raop_t *raop)
 434 {
 435         if (raop) {
 436                 raop_stop(raop);
 437
 438                 httpd_destroy(raop->httpd);
 439                 rsakey_destroy(raop->rsakey);
 440                 logger_destroy(raop->logger);
 441                 free(raop);
 442
 443                 /* Cleanup the network */
 444                 netutils_cleanup();
 445         }
 446 }
 447
 448 int
 449 raop_is_running(raop_t *raop)
 450 {
 451         assert(raop);
 452
 453         return httpd_is_running(raop->httpd);
 454 }
 455
 456 void
 457 raop_set_log_level(raop_t *raop, int level)
 458 {
 459         assert(raop);
 460
 461         logger_set_level(raop->logger, level);
 462 }
 463
 464 void
 465 raop_set_log_callback(raop_t *raop, raop_log_callback_t callback, void *cls)
 466 {
 467         assert(raop);
 468
 469         logger_set_callback(raop->logger, callback, cls);
 470 }
 471
 472 int
 473 raop_start(raop_t *raop, unsigned short *port, const char *hwaddr, int hwaddrlen, const char *password)
 474 {
 475         assert(raop);
 476         assert(port);
 477         assert(hwaddr);
 478
 479         /* Validate hardware address */
 480         if (hwaddrlen > MAX_HWADDR_LEN) {
 481                 return -1;
 482         }
 483
 484         memset(raop->password, 0, sizeof(raop->password));
 485         if (password) {
 486                 /* Validate password */
 487                 if (strlen(password) > MAX_PASSWORD_LEN) {
 488                         return -1;
 489                 }
 490
 491                 /* Copy password to the raop structure */
 492                 strncpy(raop->password, password, MAX_PASSWORD_LEN);
 493         }
 494
 495         /* Copy hwaddr to the raop structure */
 496         memcpy(raop->hwaddr, hwaddr, hwaddrlen);
 497         raop->hwaddrlen = hwaddrlen;
 498
 499         return httpd_start(raop->httpd, port);
 500 }
 501
 502 void
 503 raop_stop(raop_t *raop)
 504 {
 505         assert(raop);
 506
 507         httpd_stop(raop->httpd);
 508 }
 509