code.delx.au - pulseaudio/blob - src/modules/raop/raop_client.c

   1 /***
   2   This file is part of PulseAudio.
   3
   4   Copyright 2008 Colin Guthrie
   5
   6   PulseAudio is free software; you can redistribute it and/or modify
   7   it under the terms of the GNU Lesser General Public License as published
   8   by the Free Software Foundation; either version 2.1 of the License,
   9   or (at your option) any later version.
  10
  11   PulseAudio is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with PulseAudio; if not, write to the Free Software
  18   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  19   USA.
  20 ***/
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <stdlib.h>
  27 #include <string.h>
  28 #include <errno.h>
  29 #include <unistd.h>
  30 #include <sys/ioctl.h>
  31
  32 #ifdef HAVE_SYS_FILIO_H
  33 #include <sys/filio.h>
  34 #endif
  35
  36 /* TODO: Replace OpenSSL with NSS */
  37 #include <openssl/err.h>
  38 #include <openssl/rand.h>
  39 #include <openssl/aes.h>
  40 #include <openssl/rsa.h>
  41 #include <openssl/engine.h>
  42
  43 #include <pulse/xmalloc.h>
  44
  45 #include <pulsecore/core-error.h>
  46 #include <pulsecore/core-util.h>
  47 #include <pulsecore/iochannel.h>
  48 #include <pulsecore/socket-util.h>
  49 #include <pulsecore/log.h>
  50 #include <pulsecore/parseaddr.h>
  51 #include <pulsecore/macro.h>
  52 #include <pulsecore/memchunk.h>
  53 #include <pulsecore/random.h>
  54
  55 #include "raop_client.h"
  56 #include "rtsp_client.h"
  57 #include "base64.h"
  58
  59 #define AES_CHUNKSIZE 16
  60
  61 #define JACK_STATUS_DISCONNECTED 0
  62 #define JACK_STATUS_CONNECTED 1
  63
  64 #define JACK_TYPE_ANALOG 0
  65 #define JACK_TYPE_DIGITAL 1
  66
  67 #define VOLUME_DEF -30
  68 #define VOLUME_MIN -144
  69 #define VOLUME_MAX 0
  70
  71 #define RAOP_PORT 5000
  72
  73
  74 struct pa_raop_client {
  75     pa_core *core;
  76     char *host;
  77     uint16_t port;
  78     char *sid;
  79     pa_rtsp_client *rtsp;
  80
  81     uint8_t jack_type;
  82     uint8_t jack_status;
  83
  84     /* Encryption Related bits */
  85     AES_KEY aes;
  86     uint8_t aes_iv[AES_CHUNKSIZE]; /* initialization vector for aes-cbc */
  87     uint8_t aes_nv[AES_CHUNKSIZE]; /* next vector for aes-cbc */
  88     uint8_t aes_key[AES_CHUNKSIZE]; /* key for aes-cbc */
  89
  90     pa_socket_client *sc;
  91     int fd;
  92
  93     uint16_t seq;
  94     uint32_t rtptime;
  95
  96     pa_raop_client_cb_t callback;
  97     void* userdata;
  98     pa_raop_client_closed_cb_t closed_callback;
  99     void* closed_userdata;
 100 };
 101
 102 /**
 103  * Function to write bits into a buffer.
 104  * @param buffer Handle to the buffer. It will be incremented if new data requires it.
 105  * @param bit_pos A pointer to a position buffer to keep track the current write location (0 for MSB, 7 for LSB)
 106  * @param size A pointer to the byte size currently written. This allows the calling function to do simple buffer overflow checks
 107  * @param data The data to write
 108  * @param data_bit_len The number of bits from data to write
 109  */
 110 static inline void bit_writer(uint8_t **buffer, uint8_t *bit_pos, int *size, uint8_t data, uint8_t data_bit_len) {
 111     int bits_left, bit_overflow;
 112     uint8_t bit_data;
 113
 114     if (!data_bit_len)
 115         return;
 116
 117     /* If bit pos is zero, we will definately use at least one bit from the current byte so size increments. */
 118     if (!*bit_pos)
 119         *size += 1;
 120
 121     /* Calc the number of bits left in the current byte of buffer */
 122     bits_left = 7 - *bit_pos  + 1;
 123     /* Calc the overflow of bits in relation to how much space we have left... */
 124     bit_overflow = bits_left - data_bit_len;
 125     if (bit_overflow >= 0) {
 126         /* We can fit the new data in our current byte */
 127         /* As we write from MSB->LSB we need to left shift by the overflow amount */
 128         bit_data = data << bit_overflow;
 129         if (*bit_pos)
 130             **buffer |= bit_data;
 131         else
 132             **buffer = bit_data;
 133         /* If our data fits exactly into the current byte, we need to increment our pointer */
 134         if (0 == bit_overflow) {
 135             /* Do not increment size as it will be incremented on next call as bit_pos is zero */
 136             *buffer += 1;
 137             *bit_pos = 0;
 138         } else {
 139             *bit_pos += data_bit_len;
 140         }
 141     } else {
 142         /* bit_overflow is negative, there for we will need a new byte from our buffer */
 143         /* Firstly fill up what's left in the current byte */
 144         bit_data = data >> -bit_overflow;
 145         **buffer |= bit_data;
 146         /* Increment our buffer pointer and size counter*/
 147         *buffer += 1;
 148         *size += 1;
 149         **buffer = data << (8 + bit_overflow);
 150         *bit_pos = -bit_overflow;
 151     }
 152 }
 153
 154 static int rsa_encrypt(uint8_t *text, int len, uint8_t *res) {
 155     const char n[] =
 156         "59dE8qLieItsH1WgjrcFRKj6eUWqi+bGLOX1HL3U3GhC/j0Qg90u3sG/1CUtwC"
 157         "5vOYvfDmFI6oSFXi5ELabWJmT2dKHzBJKa3k9ok+8t9ucRqMd6DZHJ2YCCLlDR"
 158         "KSKv6kDqnw4UwPdpOMXziC/AMj3Z/lUVX1G7WSHCAWKf1zNS1eLvqr+boEjXuB"
 159         "OitnZ/bDzPHrTOZz0Dew0uowxf/+sG+NCK3eQJVxqcaJ/vEHKIVd2M+5qL71yJ"
 160         "Q+87X6oV3eaYvt3zWZYD6z5vYTcrtij2VZ9Zmni/UAaHqn9JdsBWLUEpVviYnh"
 161         "imNVvYFZeCXg/IdTQ+x4IRdiXNv5hEew==";
 162     const char e[] = "AQAB";
 163     uint8_t modules[256];
 164     uint8_t exponent[8];
 165     int size;
 166     RSA *rsa;
 167
 168     rsa = RSA_new();
 169     size = pa_base64_decode(n, modules);
 170     rsa->n = BN_bin2bn(modules, size, NULL);
 171     size = pa_base64_decode(e, exponent);
 172     rsa->e = BN_bin2bn(exponent, size, NULL);
 173
 174     size = RSA_public_encrypt(len, text, res, rsa, RSA_PKCS1_OAEP_PADDING);
 175     RSA_free(rsa);
 176     return size;
 177 }
 178
 179 static int aes_encrypt(pa_raop_client* c, uint8_t *data, int size) {
 180     uint8_t *buf;
 181     int i=0, j;
 182
 183     pa_assert(c);
 184
 185     memcpy(c->aes_nv, c->aes_iv, AES_CHUNKSIZE);
 186     while (i+AES_CHUNKSIZE <= size) {
 187         buf = data + i;
 188         for (j=0; j<AES_CHUNKSIZE; ++j)
 189             buf[j] ^= c->aes_nv[j];
 190
 191         AES_encrypt(buf, buf, &c->aes);
 192         memcpy(c->aes_nv, buf, AES_CHUNKSIZE);
 193         i += AES_CHUNKSIZE;
 194     }
 195     return i;
 196 }
 197
 198 static inline void rtrimchar(char *str, char rc) {
 199     char *sp = str + strlen(str) - 1;
 200     while (sp >= str && *sp == rc) {
 201         *sp = '\0';
 202         sp -= 1;
 203     }
 204 }
 205
 206 static void on_connection(pa_socket_client *sc, pa_iochannel *io, void *userdata) {
 207     pa_raop_client *c = userdata;
 208
 209     pa_assert(sc);
 210     pa_assert(c);
 211     pa_assert(c->sc == sc);
 212     pa_assert(c->fd < 0);
 213     pa_assert(c->callback);
 214
 215     pa_socket_client_unref(c->sc);
 216     c->sc = NULL;
 217
 218     if (!io) {
 219         pa_log("Connection failed: %s", pa_cstrerror(errno));
 220         return;
 221     }
 222
 223     c->fd = pa_iochannel_get_send_fd(io);
 224
 225     pa_iochannel_set_noclose(io, TRUE);
 226     pa_iochannel_free(io);
 227
 228     pa_make_tcp_socket_low_delay(c->fd);
 229
 230     pa_log_debug("Connection established");
 231     c->callback(c->fd, c->userdata);
 232 }
 233
 234 static void rtsp_cb(pa_rtsp_client *rtsp, pa_rtsp_state state, pa_headerlist* headers, void *userdata) {
 235     pa_raop_client* c = userdata;
 236     pa_assert(c);
 237     pa_assert(rtsp);
 238     pa_assert(rtsp == c->rtsp);
 239
 240     switch (state) {
 241         case STATE_CONNECT: {
 242             int i;
 243             uint8_t rsakey[512];
 244             char *key, *iv, *sac, *sdp;
 245             uint16_t rand_data;
 246             const char *ip;
 247             char *url;
 248
 249             pa_log_debug("RAOP: CONNECTED");
 250             ip = pa_rtsp_localip(c->rtsp);
 251             /* First of all set the url properly */
 252             url = pa_sprintf_malloc("rtsp://%s/%s", ip, c->sid);
 253             pa_rtsp_set_url(c->rtsp, url);
 254             pa_xfree(url);
 255
 256             /* Now encrypt our aes_public key to send to the device */
 257             i = rsa_encrypt(c->aes_key, AES_CHUNKSIZE, rsakey);
 258             pa_base64_encode(rsakey, i, &key);
 259             rtrimchar(key, '=');
 260             pa_base64_encode(c->aes_iv, AES_CHUNKSIZE, &iv);
 261             rtrimchar(iv, '=');
 262
 263             pa_random(&rand_data, sizeof(rand_data));
 264             pa_base64_encode(&rand_data, AES_CHUNKSIZE, &sac);
 265             rtrimchar(sac, '=');
 266             pa_rtsp_add_header(c->rtsp, "Apple-Challenge", sac);
 267             sdp = pa_sprintf_malloc(
 268                 "v=0\r\n"
 269                 "o=iTunes %s 0 IN IP4 %s\r\n"
 270                 "s=iTunes\r\n"
 271                 "c=IN IP4 %s\r\n"
 272                 "t=0 0\r\n"
 273                 "m=audio 0 RTP/AVP 96\r\n"
 274                 "a=rtpmap:96 AppleLossless\r\n"
 275                 "a=fmtp:96 4096 0 16 40 10 14 2 255 0 0 44100\r\n"
 276                 "a=rsaaeskey:%s\r\n"
 277                 "a=aesiv:%s\r\n",
 278                 c->sid, ip, c->host, key, iv);
 279             pa_rtsp_announce(c->rtsp, sdp);
 280             pa_xfree(key);
 281             pa_xfree(iv);
 282             pa_xfree(sac);
 283             pa_xfree(sdp);
 284             break;
 285         }
 286
 287         case STATE_ANNOUNCE:
 288             pa_log_debug("RAOP: ANNOUNCED");
 289             pa_rtsp_remove_header(c->rtsp, "Apple-Challenge");
 290             pa_rtsp_setup(c->rtsp);
 291             break;
 292
 293         case STATE_SETUP: {
 294             char *aj = pa_xstrdup(pa_headerlist_gets(headers, "Audio-Jack-Status"));
 295             pa_log_debug("RAOP: SETUP");
 296             if (aj) {
 297                 char *token, *pc;
 298                 char delimiters[] = ";";
 299                 const char* token_state = NULL;
 300                 c->jack_type = JACK_TYPE_ANALOG;
 301                 c->jack_status = JACK_STATUS_DISCONNECTED;
 302
 303                 while ((token = pa_split(aj, delimiters, &token_state))) {
 304                     if ((pc = strstr(token, "="))) {
 305                       *pc = 0;
 306                       if (pa_streq(token, "type") && pa_streq(pc+1, "digital")) {
 307                           c->jack_type = JACK_TYPE_DIGITAL;
 308                       }
 309                     } else {
 310                         if (pa_streq(token, "connected"))
 311                             c->jack_status = JACK_STATUS_CONNECTED;
 312                     }
 313                     pa_xfree(token);
 314                 }
 315                 pa_xfree(aj);
 316             } else {
 317                 pa_log_warn("Audio Jack Status missing");
 318             }
 319             pa_rtsp_record(c->rtsp, &c->seq, &c->rtptime);
 320             break;
 321         }
 322
 323         case STATE_RECORD: {
 324             uint32_t port = pa_rtsp_serverport(c->rtsp);
 325             pa_log_debug("RAOP: RECORDED");
 326
 327             if (!(c->sc = pa_socket_client_new_string(c->core->mainloop, TRUE, c->host, port))) {
 328                 pa_log("failed to connect to server '%s:%d'", c->host, port);
 329                 return;
 330             }
 331             pa_socket_client_set_callback(c->sc, on_connection, c);
 332             break;
 333         }
 334
 335         case STATE_FLUSH:
 336             pa_log_debug("RAOP: FLUSHED");
 337             break;
 338
 339         case STATE_TEARDOWN:
 340             pa_log_debug("RAOP: TEARDOWN");
 341             break;
 342
 343         case STATE_SET_PARAMETER:
 344             pa_log_debug("RAOP: SET_PARAMETER");
 345             break;
 346
 347         case STATE_DISCONNECTED:
 348             pa_assert(c->closed_callback);
 349             pa_assert(c->rtsp);
 350
 351             pa_log_debug("RTSP control channel closed");
 352             pa_rtsp_client_free(c->rtsp);
 353             c->rtsp = NULL;
 354             if (c->fd > 0) {
 355                 /* We do not close the fd, we leave it to the closed callback to do that */
 356                 c->fd = -1;
 357             }
 358             if (c->sc) {
 359                 pa_socket_client_unref(c->sc);
 360                 c->sc = NULL;
 361             }
 362             pa_xfree(c->sid);
 363             c->sid = NULL;
 364             c->closed_callback(c->closed_userdata);
 365             break;
 366     }
 367 }
 368
 369 pa_raop_client* pa_raop_client_new(pa_core *core, const char* host) {
 370     pa_parsed_address a;
 371     pa_raop_client* c = pa_xnew0(pa_raop_client, 1);
 372
 373     pa_assert(core);
 374     pa_assert(host);
 375
 376     if (pa_parse_address(host, &a) < 0 || a.type == PA_PARSED_ADDRESS_UNIX)
 377         return NULL;
 378
 379     c->core = core;
 380     c->fd = -1;
 381
 382     c->host = pa_xstrdup(a.path_or_host);
 383     if (a.port)
 384         c->port = a.port;
 385     else
 386         c->port = RAOP_PORT;
 387
 388     if (pa_raop_connect(c)) {
 389         pa_raop_client_free(c);
 390         return NULL;
 391     }
 392     return c;
 393 }
 394
 395
 396 void pa_raop_client_free(pa_raop_client* c) {
 397     pa_assert(c);
 398
 399     if (c->rtsp)
 400         pa_rtsp_client_free(c->rtsp);
 401     if (c->sid)
 402         pa_xfree(c->sid);
 403     pa_xfree(c->host);
 404     pa_xfree(c);
 405 }
 406
 407
 408 int pa_raop_connect(pa_raop_client* c) {
 409     char *sci;
 410     struct {
 411         uint32_t a;
 412         uint32_t b;
 413         uint32_t c;
 414     } rand_data;
 415
 416     pa_assert(c);
 417
 418     if (c->rtsp) {
 419         pa_log_debug("Connection already in progress");
 420         return 0;
 421     }
 422
 423     c->rtsp = pa_rtsp_client_new(c->core->mainloop, c->host, c->port, "iTunes/4.6 (Macintosh; U; PPC Mac OS X 10.3)");
 424
 425     /* Initialise the AES encryption system */
 426     pa_random(c->aes_iv, sizeof(c->aes_iv));
 427     pa_random(c->aes_key, sizeof(c->aes_key));
 428     memcpy(c->aes_nv, c->aes_iv, sizeof(c->aes_nv));
 429     AES_set_encrypt_key(c->aes_key, 128, &c->aes);
 430
 431     /* Generate random instance id */
 432     pa_random(&rand_data, sizeof(rand_data));
 433     c->sid = pa_sprintf_malloc("%u", rand_data.a);
 434     sci = pa_sprintf_malloc("%08x%08x",rand_data.b, rand_data.c);
 435     pa_rtsp_add_header(c->rtsp, "Client-Instance", sci);
 436     pa_xfree(sci);
 437     pa_rtsp_set_callback(c->rtsp, rtsp_cb, c);
 438     return pa_rtsp_connect(c->rtsp);
 439 }
 440
 441
 442 int pa_raop_flush(pa_raop_client* c) {
 443     pa_assert(c);
 444
 445     pa_rtsp_flush(c->rtsp, c->seq, c->rtptime);
 446     return 0;
 447 }
 448
 449
 450 int pa_raop_client_set_volume(pa_raop_client* c, pa_volume_t volume) {
 451     int rv;
 452     double db;
 453     char *param;
 454
 455     pa_assert(c);
 456
 457     db = pa_sw_volume_to_dB(volume);
 458     if (db < VOLUME_MIN)
 459         db = VOLUME_MIN;
 460     else if (db > VOLUME_MAX)
 461         db = VOLUME_MAX;
 462
 463     param = pa_sprintf_malloc("volume: %0.6f\r\n",  db);
 464
 465     /* We just hit and hope, cannot wait for the callback */
 466     rv = pa_rtsp_setparameter(c->rtsp, param);
 467     pa_xfree(param);
 468     return rv;
 469 }
 470
 471
 472 int pa_raop_client_encode_sample(pa_raop_client* c, pa_memchunk* raw, pa_memchunk* encoded) {
 473     uint16_t len;
 474     size_t bufmax;
 475     uint8_t *bp, bpos;
 476     uint8_t *ibp, *maxibp;
 477     int size;
 478     uint8_t *b, *p;
 479     uint32_t bsize;
 480     size_t length;
 481     static uint8_t header[] = {
 482         0x24, 0x00, 0x00, 0x00,
 483         0xF0, 0xFF, 0x00, 0x00,
 484         0x00, 0x00, 0x00, 0x00,
 485         0x00, 0x00, 0x00, 0x00,
 486     };
 487     int header_size = sizeof(header);
 488
 489     pa_assert(c);
 490     pa_assert(c->fd > 0);
 491     pa_assert(raw);
 492     pa_assert(raw->memblock);
 493     pa_assert(raw->length > 0);
 494     pa_assert(encoded);
 495
 496     /* We have to send 4 byte chunks */
 497     bsize = (int)(raw->length / 4);
 498     length = bsize * 4;
 499
 500     /* Leave 16 bytes extra to allow for the ALAC header which is about 55 bits */
 501     bufmax = length + header_size + 16;
 502     pa_memchunk_reset(encoded);
 503     encoded->memblock = pa_memblock_new(c->core->mempool, bufmax);
 504     b = pa_memblock_acquire(encoded->memblock);
 505     memcpy(b, header, header_size);
 506
 507     /* Now write the actual samples */
 508     bp = b + header_size;
 509     size = bpos = 0;
 510     bit_writer(&bp,&bpos,&size,1,3); /* channel=1, stereo */
 511     bit_writer(&bp,&bpos,&size,0,4); /* unknown */
 512     bit_writer(&bp,&bpos,&size,0,8); /* unknown */
 513     bit_writer(&bp,&bpos,&size,0,4); /* unknown */
 514     bit_writer(&bp,&bpos,&size,1,1); /* hassize */
 515     bit_writer(&bp,&bpos,&size,0,2); /* unused */
 516     bit_writer(&bp,&bpos,&size,1,1); /* is-not-compressed */
 517
 518     /* size of data, integer, big endian */
 519     bit_writer(&bp,&bpos,&size,(bsize>>24)&0xff,8);
 520     bit_writer(&bp,&bpos,&size,(bsize>>16)&0xff,8);
 521     bit_writer(&bp,&bpos,&size,(bsize>>8)&0xff,8);
 522     bit_writer(&bp,&bpos,&size,(bsize)&0xff,8);
 523
 524     ibp = p = pa_memblock_acquire(raw->memblock);
 525     maxibp = p + raw->length - 4;
 526     while (ibp <= maxibp) {
 527         /* Byte swap stereo data */
 528         bit_writer(&bp,&bpos,&size,*(ibp+1),8);
 529         bit_writer(&bp,&bpos,&size,*(ibp+0),8);
 530         bit_writer(&bp,&bpos,&size,*(ibp+3),8);
 531         bit_writer(&bp,&bpos,&size,*(ibp+2),8);
 532         ibp += 4;
 533         raw->index += 4;
 534         raw->length -= 4;
 535     }
 536     pa_memblock_release(raw->memblock);
 537     encoded->length = header_size + size;
 538
 539     /* store the length (endian swapped: make this better) */
 540     len = size + header_size - 4;
 541     *(b + 2) = len >> 8;
 542     *(b + 3) = len & 0xff;
 543
 544     /* encrypt our data */
 545     aes_encrypt(c, (b + header_size), size);
 546
 547     /* We're done with the chunk */
 548     pa_memblock_release(encoded->memblock);
 549
 550     return 0;
 551 }
 552
 553
 554 void pa_raop_client_set_callback(pa_raop_client* c, pa_raop_client_cb_t callback, void *userdata) {
 555     pa_assert(c);
 556
 557     c->callback = callback;
 558     c->userdata = userdata;
 559 }
 560
 561 void pa_raop_client_set_closed_callback(pa_raop_client* c, pa_raop_client_closed_cb_t callback, void *userdata) {
 562     pa_assert(c);
 563
 564     c->closed_callback = callback;
 565     c->closed_userdata = userdata;
 566 }