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/macro.h>
  51 #include <pulsecore/memchunk.h>
  52 #include <pulsecore/random.h>
  53
  54 #include "raop_client.h"
  55 #include "rtsp_client.h"
  56 #include "base64.h"
  57
  58 #define AES_CHUNKSIZE 16
  59
  60 #define JACK_STATUS_DISCONNECTED 0
  61 #define JACK_STATUS_CONNECTED 1
  62
  63 #define JACK_TYPE_ANALOG 0
  64 #define JACK_TYPE_DIGITAL 1
  65
  66 #define VOLUME_DEF -30
  67 #define VOLUME_MIN -144
  68 #define VOLUME_MAX 0
  69
  70
  71 struct pa_raop_client {
  72     pa_core *core;
  73     char *host;
  74     char *sid;
  75     pa_rtsp_client *rtsp;
  76
  77     uint8_t jack_type;
  78     uint8_t jack_status;
  79
  80     /* Encryption Related bits */
  81     AES_KEY aes;
  82     uint8_t aes_iv[AES_CHUNKSIZE]; /* initialization vector for aes-cbc */
  83     uint8_t aes_nv[AES_CHUNKSIZE]; /* next vector for aes-cbc */
  84     uint8_t aes_key[AES_CHUNKSIZE]; /* key for aes-cbc */
  85
  86     pa_socket_client *sc;
  87     int fd;
  88
  89     uint16_t seq;
  90     uint32_t rtptime;
  91
  92     pa_raop_client_cb_t callback;
  93     void* userdata;
  94     pa_raop_client_closed_cb_t closed_callback;
  95     void* closed_userdata;
  96 };
  97
  98 /**
  99  * Function to write bits into a buffer.
 100  * @param buffer Handle to the buffer. It will be incremented if new data requires it.
 101  * @param bit_pos A pointer to a position buffer to keep track the current write location (0 for MSB, 7 for LSB)
 102  * @param size A pointer to the byte size currently written. This allows the calling function to do simple buffer overflow checks
 103  * @param data The data to write
 104  * @param data_bit_len The number of bits from data to write
 105  */
 106 static inline void bit_writer(uint8_t **buffer, uint8_t *bit_pos, int *size, uint8_t data, uint8_t data_bit_len) {
 107     int bits_left, bit_overflow;
 108     uint8_t bit_data;
 109
 110     if (!data_bit_len)
 111         return;
 112
 113     /* If bit pos is zero, we will definatly use at least one bit from the current byte so size increments. */
 114     if (!*bit_pos)
 115         *size += 1;
 116
 117     /* Calc the number of bits left in the current byte of buffer */
 118     bits_left = 7 - *bit_pos  + 1;
 119     /* Calc the overflow of bits in relation to how much space we have left... */
 120     bit_overflow = bits_left - data_bit_len;
 121     if (bit_overflow >= 0) {
 122         /* We can fit the new data in our current byte */
 123         /* As we write from MSB->LSB we need to left shift by the overflow amount */
 124         bit_data = data << bit_overflow;
 125         if (*bit_pos)
 126             **buffer |= bit_data;
 127         else
 128             **buffer = bit_data;
 129         /* If our data fits exactly into the current byte, we need to increment our pointer */
 130         if (0 == bit_overflow) {
 131             /* Do not increment size as it will be incremeneted on next call as bit_pos is zero */
 132             *buffer += 1;
 133             *bit_pos = 0;
 134         } else {
 135             *bit_pos += data_bit_len;
 136         }
 137     } else {
 138         /* bit_overflow is negative, there for we will need a new byte from our buffer */
 139         /* Firstly fill up what's left in the current byte */
 140         bit_data = data >> -bit_overflow;
 141         **buffer |= bit_data;
 142         /* Increment our buffer pointer and size counter*/
 143         *buffer += 1;
 144         *size += 1;
 145         **buffer = data << (8 + bit_overflow);
 146         *bit_pos = -bit_overflow;
 147     }
 148 }
 149
 150 static int rsa_encrypt(uint8_t *text, int len, uint8_t *res) {
 151     const char n[] =
 152         "59dE8qLieItsH1WgjrcFRKj6eUWqi+bGLOX1HL3U3GhC/j0Qg90u3sG/1CUtwC"
 153         "5vOYvfDmFI6oSFXi5ELabWJmT2dKHzBJKa3k9ok+8t9ucRqMd6DZHJ2YCCLlDR"
 154         "KSKv6kDqnw4UwPdpOMXziC/AMj3Z/lUVX1G7WSHCAWKf1zNS1eLvqr+boEjXuB"
 155         "OitnZ/bDzPHrTOZz0Dew0uowxf/+sG+NCK3eQJVxqcaJ/vEHKIVd2M+5qL71yJ"
 156         "Q+87X6oV3eaYvt3zWZYD6z5vYTcrtij2VZ9Zmni/UAaHqn9JdsBWLUEpVviYnh"
 157         "imNVvYFZeCXg/IdTQ+x4IRdiXNv5hEew==";
 158     const char e[] = "AQAB";
 159     uint8_t modules[256];
 160     uint8_t exponent[8];
 161     int size;
 162     RSA *rsa;
 163
 164     rsa = RSA_new();
 165     size = pa_base64_decode(n, modules);
 166     rsa->n = BN_bin2bn(modules, size, NULL);
 167     size = pa_base64_decode(e, exponent);
 168     rsa->e = BN_bin2bn(exponent, size, NULL);
 169
 170     size = RSA_public_encrypt(len, text, res, rsa, RSA_PKCS1_OAEP_PADDING);
 171     RSA_free(rsa);
 172     return size;
 173 }
 174
 175 static int aes_encrypt(pa_raop_client* c, uint8_t *data, int size) {
 176     uint8_t *buf;
 177     int i=0, j;
 178
 179     pa_assert(c);
 180
 181     memcpy(c->aes_nv, c->aes_iv, AES_CHUNKSIZE);
 182     while (i+AES_CHUNKSIZE <= size) {
 183         buf = data + i;
 184         for (j=0; j<AES_CHUNKSIZE; ++j)
 185             buf[j] ^= c->aes_nv[j];
 186
 187         AES_encrypt(buf, buf, &c->aes);
 188         memcpy(c->aes_nv, buf, AES_CHUNKSIZE);
 189         i += AES_CHUNKSIZE;
 190     }
 191     return i;
 192 }
 193
 194 static inline void rtrimchar(char *str, char rc) {
 195     char *sp = str + strlen(str) - 1;
 196     while (sp >= str && *sp == rc) {
 197         *sp = '\0';
 198         sp -= 1;
 199     }
 200 }
 201
 202 static void on_connection(pa_socket_client *sc, pa_iochannel *io, void *userdata) {
 203     pa_raop_client *c = userdata;
 204
 205     pa_assert(sc);
 206     pa_assert(c);
 207     pa_assert(c->sc == sc);
 208     pa_assert(c->fd < 0);
 209     pa_assert(c->callback);
 210
 211     pa_socket_client_unref(c->sc);
 212     c->sc = NULL;
 213
 214     if (!io) {
 215         pa_log("Connection failed: %s", pa_cstrerror(errno));
 216         return;
 217     }
 218
 219     c->fd = pa_iochannel_get_send_fd(io);
 220
 221     pa_iochannel_set_noclose(io, TRUE);
 222     pa_iochannel_socket_set_sndbuf(io, 1024);
 223     pa_iochannel_free(io);
 224
 225     pa_make_tcp_socket_low_delay(c->fd);
 226
 227     pa_log_debug("Connection established");
 228     c->callback(c->fd, c->userdata);
 229 }
 230
 231 static void rtsp_cb(pa_rtsp_client *rtsp, pa_rtsp_state state, pa_headerlist* headers, void *userdata) {
 232     pa_raop_client* c = userdata;
 233     pa_assert(c);
 234     pa_assert(rtsp);
 235     pa_assert(rtsp == c->rtsp);
 236
 237     switch (state) {
 238         case STATE_CONNECT: {
 239             int i;
 240             uint8_t rsakey[512];
 241             char *key, *iv, *sac, *sdp;
 242             uint16_t rand_data;
 243             const char *ip;
 244             char *url;
 245
 246             pa_log_debug("RAOP: CONNECTED");
 247             ip = pa_rtsp_localip(c->rtsp);
 248             /* First of all set the url properly */
 249             url = pa_sprintf_malloc("rtsp://%s/%s", ip, c->sid);
 250             pa_rtsp_set_url(c->rtsp, url);
 251             pa_xfree(url);
 252
 253             /* Now encrypt our aes_public key to send to the device */
 254             i = rsa_encrypt(c->aes_key, AES_CHUNKSIZE, rsakey);
 255             pa_base64_encode(rsakey, i, &key);
 256             rtrimchar(key, '=');
 257             pa_base64_encode(c->aes_iv, AES_CHUNKSIZE, &iv);
 258             rtrimchar(iv, '=');
 259
 260             pa_random(&rand_data, sizeof(rand_data));
 261             pa_base64_encode(&rand_data, AES_CHUNKSIZE, &sac);
 262             rtrimchar(sac, '=');
 263             pa_rtsp_add_header(c->rtsp, "Apple-Challenge", sac);
 264             sdp = pa_sprintf_malloc(
 265                 "v=0\r\n"
 266                 "o=iTunes %s 0 IN IP4 %s\r\n"
 267                 "s=iTunes\r\n"
 268                 "c=IN IP4 %s\r\n"
 269                 "t=0 0\r\n"
 270                 "m=audio 0 RTP/AVP 96\r\n"
 271                 "a=rtpmap:96 AppleLossless\r\n"
 272                 "a=fmtp:96 4096 0 16 40 10 14 2 255 0 0 44100\r\n"
 273                 "a=rsaaeskey:%s\r\n"
 274                 "a=aesiv:%s\r\n",
 275                 c->sid, ip, c->host, key, iv);
 276             pa_rtsp_announce(c->rtsp, sdp);
 277             pa_xfree(key);
 278             pa_xfree(iv);
 279             pa_xfree(sac);
 280             pa_xfree(sdp);
 281             break;
 282         }
 283
 284         case STATE_ANNOUNCE:
 285             pa_log_debug("RAOP: ANNOUNCED");
 286             pa_rtsp_remove_header(c->rtsp, "Apple-Challenge");
 287             pa_rtsp_setup(c->rtsp);
 288             break;
 289
 290         case STATE_SETUP: {
 291             char *aj = pa_xstrdup(pa_headerlist_gets(headers, "Audio-Jack-Status"));
 292             pa_log_debug("RAOP: SETUP");
 293             if (aj) {
 294                 char *token, *pc;
 295                 char delimiters[] = ";";
 296                 const char* token_state = NULL;
 297                 c->jack_type = JACK_TYPE_ANALOG;
 298                 c->jack_status = JACK_STATUS_DISCONNECTED;
 299
 300                 while ((token = pa_split(aj, delimiters, &token_state))) {
 301                     if ((pc = strstr(token, "="))) {
 302                       *pc = 0;
 303                       if (!strcmp(token, "type") && !strcmp(pc+1, "digital")) {
 304                           c->jack_type = JACK_TYPE_DIGITAL;
 305                       }
 306                     } else {
 307                         if (!strcmp(token,"connected"))
 308                             c->jack_status = JACK_STATUS_CONNECTED;
 309                     }
 310                     pa_xfree(token);
 311                 }
 312                 pa_xfree(aj);
 313             } else {
 314                 pa_log_warn("Audio Jack Status missing");
 315             }
 316             pa_rtsp_record(c->rtsp, &c->seq, &c->rtptime);
 317             break;
 318         }
 319
 320         case STATE_RECORD: {
 321             uint32_t port = pa_rtsp_serverport(c->rtsp);
 322             pa_log_debug("RAOP: RECORDED");
 323
 324             if (!(c->sc = pa_socket_client_new_string(c->core->mainloop, TRUE, c->host, port))) {
 325                 pa_log("failed to connect to server '%s:%d'", c->host, port);
 326                 return;
 327             }
 328             pa_socket_client_set_callback(c->sc, on_connection, c);
 329             break;
 330         }
 331
 332         case STATE_FLUSH:
 333             pa_log_debug("RAOP: FLUSHED");
 334             break;
 335
 336         case STATE_TEARDOWN:
 337             pa_log_debug("RAOP: TEARDOWN");
 338             break;
 339
 340         case STATE_SET_PARAMETER:
 341             pa_log_debug("RAOP: SET_PARAMETER");
 342             break;
 343
 344         case STATE_DISCONNECTED:
 345             pa_assert(c->closed_callback);
 346             pa_assert(c->rtsp);
 347
 348             pa_log_debug("RTSP control channel closed");
 349             pa_rtsp_client_free(c->rtsp);
 350             c->rtsp = NULL;
 351             if (c->fd > 0) {
 352                 /* We do not close the fd, we leave it to the closed callback to do that */
 353                 c->fd = -1;
 354             }
 355             if (c->sc) {
 356                 pa_socket_client_unref(c->sc);
 357                 c->sc = NULL;
 358             }
 359             pa_xfree(c->sid);
 360             c->sid = NULL;
 361             c->closed_callback(c->closed_userdata);
 362             break;
 363     }
 364 }
 365
 366 pa_raop_client* pa_raop_client_new(pa_core *core, const char* host) {
 367     pa_raop_client* c = pa_xnew0(pa_raop_client, 1);
 368
 369     pa_assert(core);
 370     pa_assert(host);
 371
 372     c->core = core;
 373     c->fd = -1;
 374     c->host = pa_xstrdup(host);
 375
 376     if (pa_raop_connect(c)) {
 377         pa_raop_client_free(c);
 378         return NULL;
 379     }
 380     return c;
 381 }
 382
 383
 384 void pa_raop_client_free(pa_raop_client* c) {
 385     pa_assert(c);
 386
 387     if (c->rtsp)
 388         pa_rtsp_client_free(c->rtsp);
 389     pa_xfree(c->host);
 390     pa_xfree(c);
 391 }
 392
 393
 394 int pa_raop_connect(pa_raop_client* c) {
 395     char *sci;
 396     struct {
 397         uint32_t a;
 398         uint32_t b;
 399         uint32_t c;
 400     } rand_data;
 401
 402     pa_assert(c);
 403
 404     if (c->rtsp) {
 405         pa_log_debug("Connection already in progress");
 406         return 0;
 407     }
 408
 409     c->rtsp = pa_rtsp_client_new(c->core->mainloop, c->host, 5000, "iTunes/4.6 (Macintosh; U; PPC Mac OS X 10.3)");
 410
 411     /* Initialise the AES encryption system */
 412     pa_random(c->aes_iv, sizeof(c->aes_iv));
 413     pa_random(c->aes_key, sizeof(c->aes_key));
 414     memcpy(c->aes_nv, c->aes_iv, sizeof(c->aes_nv));
 415     AES_set_encrypt_key(c->aes_key, 128, &c->aes);
 416
 417     /* Generate random instance id */
 418     pa_random(&rand_data, sizeof(rand_data));
 419     c->sid = pa_sprintf_malloc("%u", rand_data.a);
 420     sci = pa_sprintf_malloc("%08x%08x",rand_data.b, rand_data.c);
 421     pa_rtsp_add_header(c->rtsp, "Client-Instance", sci);
 422     pa_xfree(sci);
 423     pa_rtsp_set_callback(c->rtsp, rtsp_cb, c);
 424     return pa_rtsp_connect(c->rtsp);
 425 }
 426
 427
 428 int pa_raop_flush(pa_raop_client* c) {
 429     pa_assert(c);
 430
 431     pa_rtsp_flush(c->rtsp, c->seq, c->rtptime);
 432     return 0;
 433 }
 434
 435
 436 int pa_raop_client_set_volume(pa_raop_client* c, pa_volume_t volume) {
 437     int rv;
 438     double db;
 439     char *param;
 440
 441     pa_assert(c);
 442
 443     db = pa_sw_volume_to_dB(volume);
 444     if (db < VOLUME_MIN)
 445         db = VOLUME_MIN;
 446     else if (db > VOLUME_MAX)
 447         db = VOLUME_MAX;
 448
 449     param = pa_sprintf_malloc("volume: %0.6f\r\n",  db);
 450
 451     /* We just hit and hope, cannot wait for the callback */
 452     rv = pa_rtsp_setparameter(c->rtsp, param);
 453     pa_xfree(param);
 454     return rv;
 455 }
 456
 457
 458 int pa_raop_client_encode_sample(pa_raop_client* c, pa_memchunk* raw, pa_memchunk* encoded) {
 459     uint16_t len;
 460     size_t bufmax;
 461     uint8_t *bp, bpos;
 462     uint8_t *ibp, *maxibp;
 463     int size;
 464     uint8_t *b, *p;
 465     uint32_t bsize;
 466     size_t length;
 467     static uint8_t header[] = {
 468         0x24, 0x00, 0x00, 0x00,
 469         0xF0, 0xFF, 0x00, 0x00,
 470         0x00, 0x00, 0x00, 0x00,
 471         0x00, 0x00, 0x00, 0x00,
 472     };
 473     int header_size = sizeof(header);
 474
 475     pa_assert(c);
 476     pa_assert(c->fd > 0);
 477     pa_assert(raw);
 478     pa_assert(raw->memblock);
 479     pa_assert(raw->length > 0);
 480     pa_assert(encoded);
 481
 482     /* We have to send 4 byte chunks */
 483     bsize = (int)(raw->length / 4);
 484     length = bsize * 4;
 485
 486     /* Leave 16 bytes extra to allow for the ALAC header which is about 55 bits */
 487     bufmax = length + header_size + 16;
 488     pa_memchunk_reset(encoded);
 489     encoded->memblock = pa_memblock_new(c->core->mempool, bufmax);
 490     b = pa_memblock_acquire(encoded->memblock);
 491     memcpy(b, header, header_size);
 492
 493     /* Now write the actual samples */
 494     bp = b + header_size;
 495     size = bpos = 0;
 496     bit_writer(&bp,&bpos,&size,1,3); /* channel=1, stereo */
 497     bit_writer(&bp,&bpos,&size,0,4); /* unknown */
 498     bit_writer(&bp,&bpos,&size,0,8); /* unknown */
 499     bit_writer(&bp,&bpos,&size,0,4); /* unknown */
 500     bit_writer(&bp,&bpos,&size,1,1); /* hassize */
 501     bit_writer(&bp,&bpos,&size,0,2); /* unused */
 502     bit_writer(&bp,&bpos,&size,1,1); /* is-not-compressed */
 503
 504     /* size of data, integer, big endian */
 505     bit_writer(&bp,&bpos,&size,(bsize>>24)&0xff,8);
 506     bit_writer(&bp,&bpos,&size,(bsize>>16)&0xff,8);
 507     bit_writer(&bp,&bpos,&size,(bsize>>8)&0xff,8);
 508     bit_writer(&bp,&bpos,&size,(bsize)&0xff,8);
 509
 510     ibp = p = pa_memblock_acquire(raw->memblock);
 511     maxibp = p + raw->length - 4;
 512     while (ibp <= maxibp) {
 513         /* Byte swap stereo data */
 514         bit_writer(&bp,&bpos,&size,*(ibp+1),8);
 515         bit_writer(&bp,&bpos,&size,*(ibp+0),8);
 516         bit_writer(&bp,&bpos,&size,*(ibp+3),8);
 517         bit_writer(&bp,&bpos,&size,*(ibp+2),8);
 518         ibp += 4;
 519         raw->index += 4;
 520         raw->length -= 4;
 521     }
 522     pa_memblock_release(raw->memblock);
 523     encoded->length = header_size + size;
 524
 525     /* store the lenght (endian swapped: make this better) */
 526     len = size + header_size - 4;
 527     *(b + 2) = len >> 8;
 528     *(b + 3) = len & 0xff;
 529
 530     /* encrypt our data */
 531     aes_encrypt(c, (b + header_size), size);
 532
 533     /* We're done with the chunk */
 534     pa_memblock_release(encoded->memblock);
 535
 536     return 0;
 537 }
 538
 539
 540 void pa_raop_client_set_callback(pa_raop_client* c, pa_raop_client_cb_t callback, void *userdata) {
 541     pa_assert(c);
 542
 543     c->callback = callback;
 544     c->userdata = userdata;
 545 }
 546
 547 void pa_raop_client_set_closed_callback(pa_raop_client* c, pa_raop_client_closed_cb_t callback, void *userdata) {
 548     pa_assert(c);
 549
 550     c->closed_callback = callback;
 551     c->closed_userdata = userdata;
 552 }