contrib/wpa_supplicant/src/wps/httpread.c

   1 /*
   2  * httpread - Manage reading file(s) from HTTP/TCP socket
   3  * Author: Ted Merrill
   4  * Copyright 2008 Atheros Communications
   5  *
   6  * This software may be distributed under the terms of the BSD license.
   7  * See README for more details.
   8  *
   9  * The files are buffered via internal callbacks from eloop, then presented to
  10  * an application callback routine when completely read into memory. May also
  11  * be used if no file is expected but just to get the header, including HTTP
  12  * replies (e.g. HTTP/1.1 200 OK etc.).
  13  *
  14  * This does not attempt to be an optimally efficient implementation, but does
  15  * attempt to be of reasonably small size and memory consumption; assuming that
  16  * only small files are to be read. A maximum file size is provided by
  17  * application and enforced.
  18  *
  19  * It is assumed that the application does not expect any of the following:
  20  * -- transfer encoding other than chunked
  21  * -- trailer fields
  22  * It is assumed that, even if the other side requested that the connection be
  23  * kept open, that we will close it (thus HTTP messages sent by application
  24  * should have the connection closed field); this is allowed by HTTP/1.1 and
  25  * simplifies things for us.
  26  *
  27  * Other limitations:
  28  * -- HTTP header may not exceed a hard-coded size.
  29  *
  30  * Notes:
  31  * This code would be massively simpler without some of the new features of
  32  * HTTP/1.1, especially chunked data.
  33  */
  34
  35 #include "includes.h"
  36
  37 #include "common.h"
  38 #include "eloop.h"
  39 #include "httpread.h"
  40
  41
  42 /* Tunable parameters */
  43 #define HTTPREAD_READBUF_SIZE 1024      /* read in chunks of this size */
  44 #define HTTPREAD_HEADER_MAX_SIZE 4096   /* max allowed for headers */
  45 #define HTTPREAD_BODYBUF_DELTA 4096     /* increase allocation by this */
  46
  47
  48 /* control instance -- actual definition (opaque to application)
  49  */
  50 struct httpread {
  51         /* information from creation */
  52         int sd;         /* descriptor of TCP socket to read from */
  53         void (*cb)(struct httpread *handle, void *cookie,
  54                     enum httpread_event e);  /* call on event */
  55         void *cookie;   /* pass to callback */
  56         int max_bytes;          /* maximum file size else abort it */
  57         int timeout_seconds;            /* 0 or total duration timeout period */
  58
  59         /* dynamically used information follows */
  60
  61         int got_hdr;            /* nonzero when header is finalized */
  62         char hdr[HTTPREAD_HEADER_MAX_SIZE+1];   /* headers stored here */
  63         int hdr_nbytes;
  64
  65         enum httpread_hdr_type hdr_type;
  66         int version;            /* 1 if we've seen 1.1 */
  67         int reply_code;         /* for type REPLY, e.g. 200 for HTTP/1.1 200 OK */
  68         int got_content_length; /* true if we know content length for sure */
  69         int content_length;     /* body length,  iff got_content_length */
  70         int chunked;            /* nonzero for chunked data */
  71         char *uri;
  72
  73         int got_body;           /* nonzero when body is finalized */
  74         char *body;
  75         int body_nbytes;
  76         int body_alloc_nbytes;  /* amount allocated */
  77
  78         int got_file;           /* here when we are done */
  79
  80         /* The following apply if data is chunked: */
  81         int in_chunk_data;      /* 0=in/at header, 1=in the data or tail*/
  82         int chunk_start;        /* offset in body of chunk hdr or data */
  83         int chunk_size;         /* data of chunk (not hdr or ending CRLF)*/
  84         int in_trailer;         /* in header fields after data (chunked only)*/
  85         enum trailer_state {
  86                 trailer_line_begin = 0,
  87                 trailer_empty_cr,       /* empty line + CR */
  88                 trailer_nonempty,
  89                 trailer_nonempty_cr,
  90         } trailer_state;
  91 };
  92
  93
  94 /* Check words for equality, where words consist of graphical characters
  95  * delimited by whitespace
  96  * Returns nonzero if "equal" doing case insensitive comparison.
  97  */
  98 static int word_eq(char *s1, char *s2)
  99 {
 100         int c1;
 101         int c2;
 102         int end1 = 0;
 103         int end2 = 0;
 104         for (;;) {
 105                 c1 = *s1++;
 106                 c2 = *s2++;
 107                 if (isalpha(c1) && isupper(c1))
 108                         c1 = tolower(c1);
 109                 if (isalpha(c2) && isupper(c2))
 110                         c2 = tolower(c2);
 111                 end1 = !isgraph(c1);
 112                 end2 = !isgraph(c2);
 113                 if (end1 || end2 || c1 != c2)
 114                         break;
 115         }
 116         return end1 && end2;  /* reached end of both words? */
 117 }
 118
 119
 120 static void httpread_timeout_handler(void *eloop_data, void *user_ctx);
 121
 122 /* httpread_destroy -- if h is non-NULL, clean up
 123  * This must eventually be called by the application following
 124  * call of the application's callback and may be called
 125  * earlier if desired.
 126  */
 127 void httpread_destroy(struct httpread *h)
 128 {
 129         wpa_printf(MSG_DEBUG, "httpread_destroy(%p)", h);
 130         if (!h)
 131                 return;
 132
 133         eloop_cancel_timeout(httpread_timeout_handler, NULL, h);
 134         eloop_unregister_sock(h->sd, EVENT_TYPE_READ);
 135         os_free(h->body);
 136         os_free(h->uri);
 137         os_memset(h, 0, sizeof(*h));  /* aid debugging */
 138         h->sd = -1;     /* aid debugging */
 139         os_free(h);
 140 }
 141
 142
 143 /* httpread_timeout_handler -- called on excessive total duration
 144  */
 145 static void httpread_timeout_handler(void *eloop_data, void *user_ctx)
 146 {
 147         struct httpread *h = user_ctx;
 148         wpa_printf(MSG_DEBUG, "httpread timeout (%p)", h);
 149         (*h->cb)(h, h->cookie, HTTPREAD_EVENT_TIMEOUT);
 150 }
 151
 152
 153 /* Analyze options only so far as is needed to correctly obtain the file.
 154  * The application can look at the raw header to find other options.
 155  */
 156 static int httpread_hdr_option_analyze(
 157         struct httpread *h,
 158         char *hbp       /* pointer to current line in header buffer */
 159         )
 160 {
 161         if (word_eq(hbp, "CONTENT-LENGTH:")) {
 162                 while (isgraph(*hbp))
 163                         hbp++;
 164                 while (*hbp == ' ' || *hbp == '\t')
 165                         hbp++;
 166                 if (!isdigit(*hbp))
 167                         return -1;
 168                 h->content_length = atol(hbp);
 169                 if (h->content_length < 0 || h->content_length > h->max_bytes) {
 170                         wpa_printf(MSG_DEBUG,
 171                                    "httpread: Unacceptable Content-Length %d",
 172                                    h->content_length);
 173                         return -1;
 174                 }
 175                 h->got_content_length = 1;
 176                 return 0;
 177         }
 178         if (word_eq(hbp, "TRANSFER_ENCODING:") ||
 179             word_eq(hbp, "TRANSFER-ENCODING:")) {
 180                 while (isgraph(*hbp))
 181                         hbp++;
 182                 while (*hbp == ' ' || *hbp == '\t')
 183                         hbp++;
 184                 /* There should (?) be no encodings of interest
 185                  * other than chunked...
 186                  */
 187                 if (word_eq(hbp, "CHUNKED")) {
 188                         h->chunked = 1;
 189                         h->in_chunk_data = 0;
 190                         /* ignore possible ;<parameters> */
 191                 }
 192                 return 0;
 193         }
 194         /* skip anything we don't know, which is a lot */
 195         return 0;
 196 }
 197
 198
 199 static int httpread_hdr_analyze(struct httpread *h)
 200 {
 201         char *hbp = h->hdr;      /* pointer into h->hdr */
 202         int standard_first_line = 1;
 203
 204         /* First line is special */
 205         h->hdr_type = HTTPREAD_HDR_TYPE_UNKNOWN;
 206         if (!isgraph(*hbp))
 207                 goto bad;
 208         if (os_strncmp(hbp, "HTTP/", 5) == 0) {
 209                 h->hdr_type = HTTPREAD_HDR_TYPE_REPLY;
 210                 standard_first_line = 0;
 211                 hbp += 5;
 212                 if (hbp[0] == '1' && hbp[1] == '.' &&
 213                     isdigit(hbp[2]) && hbp[2] != '0')
 214                         h->version = 1;
 215                 while (isgraph(*hbp))
 216                         hbp++;
 217                 while (*hbp == ' ' || *hbp == '\t')
 218                         hbp++;
 219                 if (!isdigit(*hbp))
 220                         goto bad;
 221                 h->reply_code = atol(hbp);
 222         } else if (word_eq(hbp, "GET"))
 223                 h->hdr_type = HTTPREAD_HDR_TYPE_GET;
 224         else if (word_eq(hbp, "HEAD"))
 225                 h->hdr_type = HTTPREAD_HDR_TYPE_HEAD;
 226         else if (word_eq(hbp, "POST"))
 227                 h->hdr_type = HTTPREAD_HDR_TYPE_POST;
 228         else if (word_eq(hbp, "PUT"))
 229                 h->hdr_type = HTTPREAD_HDR_TYPE_PUT;
 230         else if (word_eq(hbp, "DELETE"))
 231                 h->hdr_type = HTTPREAD_HDR_TYPE_DELETE;
 232         else if (word_eq(hbp, "TRACE"))
 233                 h->hdr_type = HTTPREAD_HDR_TYPE_TRACE;
 234         else if (word_eq(hbp, "CONNECT"))
 235                 h->hdr_type = HTTPREAD_HDR_TYPE_CONNECT;
 236         else if (word_eq(hbp, "NOTIFY"))
 237                 h->hdr_type = HTTPREAD_HDR_TYPE_NOTIFY;
 238         else if (word_eq(hbp, "M-SEARCH"))
 239                 h->hdr_type = HTTPREAD_HDR_TYPE_M_SEARCH;
 240         else if (word_eq(hbp, "M-POST"))
 241                 h->hdr_type = HTTPREAD_HDR_TYPE_M_POST;
 242         else if (word_eq(hbp, "SUBSCRIBE"))
 243                 h->hdr_type = HTTPREAD_HDR_TYPE_SUBSCRIBE;
 244         else if (word_eq(hbp, "UNSUBSCRIBE"))
 245                 h->hdr_type = HTTPREAD_HDR_TYPE_UNSUBSCRIBE;
 246         else {
 247         }
 248
 249         if (standard_first_line) {
 250                 char *rawuri;
 251                 char *uri;
 252                 /* skip type */
 253                 while (isgraph(*hbp))
 254                         hbp++;
 255                 while (*hbp == ' ' || *hbp == '\t')
 256                         hbp++;
 257                 /* parse uri.
 258                  * Find length, allocate memory for translated
 259                  * copy, then translate by changing %<hex><hex>
 260                  * into represented value.
 261                  */
 262                 rawuri = hbp;
 263                 while (isgraph(*hbp))
 264                         hbp++;
 265                 h->uri = os_malloc((hbp - rawuri) + 1);
 266                 if (h->uri == NULL)
 267                         goto bad;
 268                 uri = h->uri;
 269                 while (rawuri < hbp) {
 270                         int c = *rawuri;
 271                         if (c == '%' &&
 272                             isxdigit(rawuri[1]) && isxdigit(rawuri[2])) {
 273                                 *uri++ = hex2byte(rawuri + 1);
 274                                 rawuri += 3;
 275                         } else {
 276                                 *uri++ = c;
 277                                 rawuri++;
 278                         }
 279                 }
 280                 *uri = 0;       /* null terminate */
 281                 while (*hbp == ' ' || *hbp == '\t')
 282                         hbp++;
 283                 /* get version */
 284                 if (0 == strncmp(hbp, "HTTP/", 5)) {
 285                         hbp += 5;
 286                         if (hbp[0] == '1' && hbp[1] == '.' &&
 287                             isdigit(hbp[2]) && hbp[2] != '0')
 288                                 h->version = 1;
 289                 }
 290         }
 291         /* skip rest of line */
 292         while (*hbp)
 293                 if (*hbp++ == '\n')
 294                         break;
 295
 296         /* Remainder of lines are options, in any order;
 297          * or empty line to terminate
 298          */
 299         for (;;) {
 300                 /* Empty line to terminate */
 301                 if (hbp[0] == '\n' ||
 302                     (hbp[0] == '\r' && hbp[1] == '\n'))
 303                         break;
 304                 if (!isgraph(*hbp))
 305                         goto bad;
 306                 if (httpread_hdr_option_analyze(h, hbp))
 307                         goto bad;
 308                 /* skip line */
 309                 while (*hbp)
 310                         if (*hbp++ == '\n')
 311                                 break;
 312         }
 313
 314         /* chunked overrides content-length always */
 315         if (h->chunked)
 316                 h->got_content_length = 0;
 317
 318         /* For some types, we should not try to read a body
 319          * This is in addition to the application determining
 320          * that we should not read a body.
 321          */
 322         switch (h->hdr_type) {
 323         case HTTPREAD_HDR_TYPE_REPLY:
 324                 /* Some codes can have a body and some not.
 325                  * For now, just assume that any other than 200
 326                  * do not...
 327                  */
 328                 if (h->reply_code != 200)
 329                         h->max_bytes = 0;
 330                 break;
 331         case HTTPREAD_HDR_TYPE_GET:
 332         case HTTPREAD_HDR_TYPE_HEAD:
 333                 /* in practice it appears that it is assumed
 334                  * that GETs have a body length of 0... ?
 335                  */
 336                 if (h->chunked == 0 && h->got_content_length == 0)
 337                         h->max_bytes = 0;
 338                 break;
 339         case HTTPREAD_HDR_TYPE_POST:
 340         case HTTPREAD_HDR_TYPE_PUT:
 341         case HTTPREAD_HDR_TYPE_DELETE:
 342         case HTTPREAD_HDR_TYPE_TRACE:
 343         case HTTPREAD_HDR_TYPE_CONNECT:
 344         case HTTPREAD_HDR_TYPE_NOTIFY:
 345         case HTTPREAD_HDR_TYPE_M_SEARCH:
 346         case HTTPREAD_HDR_TYPE_M_POST:
 347         case HTTPREAD_HDR_TYPE_SUBSCRIBE:
 348         case HTTPREAD_HDR_TYPE_UNSUBSCRIBE:
 349         default:
 350                 break;
 351         }
 352
 353         return 0;
 354
 355 bad:
 356         /* Error */
 357         return -1;
 358 }
 359
 360
 361 /* httpread_read_handler -- called when socket ready to read
 362  *
 363  * Note: any extra data we read past end of transmitted file is ignored;
 364  * if we were to support keeping connections open for multiple files then
 365  * this would have to be addressed.
 366  */
 367 static void httpread_read_handler(int sd, void *eloop_ctx, void *sock_ctx)
 368 {
 369         struct httpread *h = sock_ctx;
 370         int nread;
 371         char *rbp;      /* pointer into read buffer */
 372         char *hbp;      /* pointer into header buffer */
 373         char *bbp;      /* pointer into body buffer */
 374         char readbuf[HTTPREAD_READBUF_SIZE];  /* temp use to read into */
 375
 376         /* read some at a time, then search for the interal
 377          * boundaries between header and data and etc.
 378          */
 379         wpa_printf(MSG_DEBUG, "httpread: Trying to read more data(%p)", h);
 380         nread = read(h->sd, readbuf, sizeof(readbuf));
 381         if (nread < 0) {
 382                 wpa_printf(MSG_DEBUG, "httpread failed: %s", strerror(errno));
 383                 goto bad;
 384         }
 385         wpa_hexdump_ascii(MSG_MSGDUMP, "httpread - read", readbuf, nread);
 386         if (nread == 0) {
 387                 /* end of transmission... this may be normal
 388                  * or may be an error... in some cases we can't
 389                  * tell which so we must assume it is normal then.
 390                  */
 391                 if (!h->got_hdr) {
 392                         /* Must at least have completed header */
 393                         wpa_printf(MSG_DEBUG, "httpread premature eof(%p)", h);
 394                         goto bad;
 395                 }
 396                 if (h->chunked || h->got_content_length) {
 397                         /* Premature EOF; e.g. dropped connection */
 398                         wpa_printf(MSG_DEBUG,
 399                                    "httpread premature eof(%p) %d/%d",
 400                                    h, h->body_nbytes,
 401                                    h->content_length);
 402                         goto bad;
 403                 }
 404                 /* No explicit length, hopefully we have all the data
 405                  * although dropped connections can cause false
 406                  * end
 407                  */
 408                 wpa_printf(MSG_DEBUG, "httpread ok eof(%p)", h);
 409                 h->got_body = 1;
 410                 goto got_file;
 411         }
 412         rbp = readbuf;
 413
 414         /* Header consists of text lines (terminated by both CR and LF)
 415          * and an empty line (CR LF only).
 416          */
 417         if (!h->got_hdr) {
 418                 hbp = h->hdr + h->hdr_nbytes;
 419                 /* add to headers until:
 420                  *      -- we run out of data in read buffer
 421                  *      -- or, we run out of header buffer room
 422                  *      -- or, we get double CRLF in headers
 423                  */
 424                 for (;;) {
 425                         if (nread == 0)
 426                                 goto get_more;
 427                         if (h->hdr_nbytes == HTTPREAD_HEADER_MAX_SIZE) {
 428                                 wpa_printf(MSG_DEBUG,
 429                                            "httpread: Too long header");
 430                                 goto bad;
 431                         }
 432                         *hbp++ = *rbp++;
 433                         nread--;
 434                         h->hdr_nbytes++;
 435                         if (h->hdr_nbytes >= 4 &&
 436                             hbp[-1] == '\n' &&
 437                             hbp[-2] == '\r' &&
 438                             hbp[-3] == '\n' &&
 439                             hbp[-4] == '\r' ) {
 440                                 h->got_hdr = 1;
 441                                 *hbp = 0;       /* null terminate */
 442                                 break;
 443                         }
 444                 }
 445                 /* here we've just finished reading the header */
 446                 if (httpread_hdr_analyze(h)) {
 447                         wpa_printf(MSG_DEBUG, "httpread bad hdr(%p)", h);
 448                         goto bad;
 449                 }
 450                 if (h->max_bytes == 0) {
 451                         wpa_printf(MSG_DEBUG, "httpread no body hdr end(%p)",
 452                                    h);
 453                         goto got_file;
 454                 }
 455                 if (h->got_content_length && h->content_length == 0) {
 456                         wpa_printf(MSG_DEBUG,
 457                                    "httpread zero content length(%p)", h);
 458                         goto got_file;
 459                 }
 460         }
 461
 462         /* Certain types of requests never have data and so
 463          * must be specially recognized.
 464          */
 465         if (!os_strncasecmp(h->hdr, "SUBSCRIBE", 9) ||
 466             !os_strncasecmp(h->hdr, "UNSUBSCRIBE", 11) ||
 467             !os_strncasecmp(h->hdr, "HEAD", 4) ||
 468             !os_strncasecmp(h->hdr, "GET", 3)) {
 469                 if (!h->got_body) {
 470                         wpa_printf(MSG_DEBUG, "httpread NO BODY for sp. type");
 471                 }
 472                 h->got_body = 1;
 473                 goto got_file;
 474         }
 475
 476         /* Data can be just plain binary data, or if "chunked"
 477          * consists of chunks each with a header, ending with
 478          * an ending header.
 479          */
 480         if (nread == 0)
 481                 goto get_more;
 482         if (!h->got_body) {
 483                 /* Here to get (more of) body */
 484                 /* ensure we have enough room for worst case for body
 485                  * plus a null termination character
 486                  */
 487                 if (h->body_alloc_nbytes < (h->body_nbytes + nread + 1)) {
 488                         char *new_body;
 489                         int new_alloc_nbytes;
 490
 491                         if (h->body_nbytes >= h->max_bytes) {
 492                                 wpa_printf(MSG_DEBUG,
 493                                            "httpread: body_nbytes=%d >= max_bytes=%d",
 494                                            h->body_nbytes, h->max_bytes);
 495                                 goto bad;
 496                         }
 497                         new_alloc_nbytes = h->body_alloc_nbytes +
 498                                 HTTPREAD_BODYBUF_DELTA;
 499                         /* For content-length case, the first time
 500                          * through we allocate the whole amount
 501                          * we need.
 502                          */
 503                         if (h->got_content_length &&
 504                             new_alloc_nbytes < (h->content_length + 1))
 505                                 new_alloc_nbytes = h->content_length + 1;
 506                         if (new_alloc_nbytes < h->body_alloc_nbytes ||
 507                             new_alloc_nbytes > h->max_bytes +
 508                             HTTPREAD_BODYBUF_DELTA) {
 509                                 wpa_printf(MSG_DEBUG,
 510                                            "httpread: Unacceptable body length %d (body_alloc_nbytes=%u max_bytes=%u)",
 511                                            new_alloc_nbytes,
 512                                            h->body_alloc_nbytes,
 513                                            h->max_bytes);
 514                                 goto bad;
 515                         }
 516                         if ((new_body = os_realloc(h->body, new_alloc_nbytes))
 517                             == NULL) {
 518                                 wpa_printf(MSG_DEBUG,
 519                                            "httpread: Failed to reallocate buffer (len=%d)",
 520                                            new_alloc_nbytes);
 521                                 goto bad;
 522                         }
 523
 524                         h->body = new_body;
 525                         h->body_alloc_nbytes = new_alloc_nbytes;
 526                 }
 527                 /* add bytes */
 528                 bbp = h->body + h->body_nbytes;
 529                 for (;;) {
 530                         int ncopy;
 531                         /* See if we need to stop */
 532                         if (h->chunked && h->in_chunk_data == 0) {
 533                                 /* in chunk header */
 534                                 char *cbp = h->body + h->chunk_start;
 535                                 if (bbp-cbp >= 2 && bbp[-2] == '\r' &&
 536                                     bbp[-1] == '\n') {
 537                                         /* end of chunk hdr line */
 538                                         /* hdr line consists solely
 539                                          * of a hex numeral and CFLF
 540                                          */
 541                                         if (!isxdigit(*cbp)) {
 542                                                 wpa_printf(MSG_DEBUG,
 543                                                            "httpread: Unexpected chunk header value (not a hex digit)");
 544                                                 goto bad;
 545                                         }
 546                                         h->chunk_size = strtoul(cbp, NULL, 16);
 547                                         if (h->chunk_size < 0 ||
 548                                             h->chunk_size > h->max_bytes) {
 549                                                 wpa_printf(MSG_DEBUG,
 550                                                            "httpread: Invalid chunk size %d",
 551                                                            h->chunk_size);
 552                                                 goto bad;
 553                                         }
 554                                         /* throw away chunk header
 555                                          * so we have only real data
 556                                          */
 557                                         h->body_nbytes = h->chunk_start;
 558                                         bbp = cbp;
 559                                         if (h->chunk_size == 0) {
 560                                                 /* end of chunking */
 561                                                 /* trailer follows */
 562                                                 h->in_trailer = 1;
 563                                                 wpa_printf(MSG_DEBUG,
 564                                                            "httpread end chunks(%p)",
 565                                                            h);
 566                                                 break;
 567                                         }
 568                                         h->in_chunk_data = 1;
 569                                         /* leave chunk_start alone */
 570                                 }
 571                         } else if (h->chunked) {
 572                                 /* in chunk data */
 573                                 if ((h->body_nbytes - h->chunk_start) ==
 574                                     (h->chunk_size + 2)) {
 575                                         /* end of chunk reached,
 576                                          * new chunk starts
 577                                          */
 578                                         /* check chunk ended w/ CRLF
 579                                          * which we'll throw away
 580                                          */
 581                                         if (bbp[-1] == '\n' &&
 582                                             bbp[-2] == '\r') {
 583                                         } else {
 584                                                 wpa_printf(MSG_DEBUG,
 585                                                            "httpread: Invalid chunk end");
 586                                                 goto bad;
 587                                         }
 588                                         h->body_nbytes -= 2;
 589                                         bbp -= 2;
 590                                         h->chunk_start = h->body_nbytes;
 591                                         h->in_chunk_data = 0;
 592                                         h->chunk_size = 0; /* just in case */
 593                                 }
 594                         } else if (h->got_content_length &&
 595                                    h->body_nbytes >= h->content_length) {
 596                                 h->got_body = 1;
 597                                 wpa_printf(MSG_DEBUG,
 598                                            "httpread got content(%p)", h);
 599                                 goto got_file;
 600                         }
 601                         if (nread <= 0)
 602                                 break;
 603                         /* Now transfer. Optimize using memcpy where we can. */
 604                         if (h->chunked && h->in_chunk_data) {
 605                                 /* copy up to remainder of chunk data
 606                                  * plus the required CR+LF at end
 607                                  */
 608                                 ncopy = (h->chunk_start + h->chunk_size + 2) -
 609                                         h->body_nbytes;
 610                         } else if (h->chunked) {
 611                                 /*in chunk header -- don't optimize */
 612                                 *bbp++ = *rbp++;
 613                                 nread--;
 614                                 h->body_nbytes++;
 615                                 continue;
 616                         } else if (h->got_content_length) {
 617                                 ncopy = h->content_length - h->body_nbytes;
 618                         } else {
 619                                 ncopy = nread;
 620                         }
 621                         /* Note: should never be 0 */
 622                         if (ncopy < 0) {
 623                                 wpa_printf(MSG_DEBUG,
 624                                            "httpread: Invalid ncopy=%d", ncopy);
 625                                 goto bad;
 626                         }
 627                         if (ncopy > nread)
 628                                 ncopy = nread;
 629                         os_memcpy(bbp, rbp, ncopy);
 630                         bbp += ncopy;
 631                         h->body_nbytes += ncopy;
 632                         rbp += ncopy;
 633                         nread -= ncopy;
 634                 }       /* body copy loop */
 635         }       /* !got_body */
 636         if (h->chunked && h->in_trailer) {
 637                 /* If "chunked" then there is always a trailer,
 638                  * consisting of zero or more non-empty lines
 639                  * ending with CR LF and then an empty line w/ CR LF.
 640                  * We do NOT support trailers except to skip them --
 641                  * this is supported (generally) by the http spec.
 642                  */
 643                 for (;;) {
 644                         int c;
 645                         if (nread <= 0)
 646                                 break;
 647                         c = *rbp++;
 648                         nread--;
 649                         switch (h->trailer_state) {
 650                         case trailer_line_begin:
 651                                 if (c == '\r')
 652                                         h->trailer_state = trailer_empty_cr;
 653                                 else
 654                                         h->trailer_state = trailer_nonempty;
 655                                 break;
 656                         case trailer_empty_cr:
 657                                 /* end empty line */
 658                                 if (c == '\n') {
 659                                         h->trailer_state = trailer_line_begin;
 660                                         h->in_trailer = 0;
 661                                         wpa_printf(MSG_DEBUG,
 662                                                    "httpread got content(%p)",
 663                                                    h);
 664                                         h->got_body = 1;
 665                                         goto got_file;
 666                                 }
 667                                 h->trailer_state = trailer_nonempty;
 668                                 break;
 669                         case trailer_nonempty:
 670                                 if (c == '\r')
 671                                         h->trailer_state = trailer_nonempty_cr;
 672                                 break;
 673                         case trailer_nonempty_cr:
 674                                 if (c == '\n')
 675                                         h->trailer_state = trailer_line_begin;
 676                                 else
 677                                         h->trailer_state = trailer_nonempty;
 678                                 break;
 679                         }
 680                 }
 681         }
 682         goto get_more;
 683
 684 bad:
 685         /* Error */
 686         wpa_printf(MSG_DEBUG, "httpread read/parse failure (%p)", h);
 687         (*h->cb)(h, h->cookie, HTTPREAD_EVENT_ERROR);
 688         return;
 689
 690 get_more:
 691         wpa_printf(MSG_DEBUG, "httpread: get more (%p)", h);
 692         return;
 693
 694 got_file:
 695         wpa_printf(MSG_DEBUG, "httpread got file %d bytes type %d",
 696                    h->body_nbytes, h->hdr_type);
 697         wpa_hexdump_ascii(MSG_MSGDUMP, "httpread: body",
 698                           h->body, h->body_nbytes);
 699         /* Null terminate for convenience of some applications */
 700         if (h->body)
 701                 h->body[h->body_nbytes] = 0; /* null terminate */
 702         h->got_file = 1;
 703         /* Assume that we do NOT support keeping connection alive,
 704          * and just in case somehow we don't get destroyed right away,
 705          * unregister now.
 706          */
 707         eloop_unregister_sock(h->sd, EVENT_TYPE_READ);
 708         /* The application can destroy us whenever they feel like...
 709          * cancel timeout.
 710          */
 711         eloop_cancel_timeout(httpread_timeout_handler, NULL, h);
 712         (*h->cb)(h, h->cookie, HTTPREAD_EVENT_FILE_READY);
 713 }
 714
 715
 716 /* httpread_create -- start a new reading session making use of eloop.
 717  * The new instance will use the socket descriptor for reading (until
 718  * it gets a file and not after) but will not close the socket, even
 719  * when the instance is destroyed (the application must do that).
 720  * Return NULL on error.
 721  *
 722  * Provided that httpread_create successfully returns a handle,
 723  * the callback fnc is called to handle httpread_event events.
 724  * The caller should do destroy on any errors or unknown events.
 725  *
 726  * Pass max_bytes == 0 to not read body at all (required for e.g.
 727  * reply to HEAD request).
 728  */
 729 struct httpread * httpread_create(
 730         int sd,  /* descriptor of TCP socket to read from */
 731         void (*cb)(struct httpread *handle, void *cookie,
 732                    enum httpread_event e),  /* call on event */
 733         void *cookie,    /* pass to callback */
 734         int max_bytes,    /* maximum body size else abort it */
 735         int timeout_seconds     /* 0; or total duration timeout period */
 736         )
 737 {
 738         struct httpread *h = NULL;
 739
 740         h = os_zalloc(sizeof(*h));
 741         if (h == NULL)
 742                 goto fail;
 743         h->sd = sd;
 744         h->cb = cb;
 745         h->cookie = cookie;
 746         h->max_bytes = max_bytes;
 747         h->timeout_seconds = timeout_seconds;
 748
 749         if (timeout_seconds > 0 &&
 750             eloop_register_timeout(timeout_seconds, 0,
 751                                    httpread_timeout_handler, NULL, h)) {
 752                 /* No way to recover (from malloc failure) */
 753                 goto fail;
 754         }
 755         if (eloop_register_sock(sd, EVENT_TYPE_READ, httpread_read_handler,
 756                                 NULL, h)) {
 757                 /* No way to recover (from malloc failure) */
 758                 goto fail;
 759         }
 760         return h;
 761
 762 fail:
 763
 764         /* Error */
 765         httpread_destroy(h);
 766         return NULL;
 767 }
 768
 769
 770 /* httpread_hdr_type_get -- When file is ready, returns header type. */
 771 enum httpread_hdr_type httpread_hdr_type_get(struct httpread *h)
 772 {
 773         return h->hdr_type;
 774 }
 775
 776
 777 /* httpread_uri_get -- When file is ready, uri_get returns (translated) URI
 778  * or possibly NULL (which would be an error).
 779  */
 780 char * httpread_uri_get(struct httpread *h)
 781 {
 782         return h->uri;
 783 }
 784
 785
 786 /* httpread_reply_code_get -- When reply is ready, returns reply code */
 787 int httpread_reply_code_get(struct httpread *h)
 788 {
 789         return h->reply_code;
 790 }
 791
 792
 793 /* httpread_length_get -- When file is ready, returns file length. */
 794 int httpread_length_get(struct httpread *h)
 795 {
 796         return h->body_nbytes;
 797 }
 798
 799
 800 /* httpread_data_get -- When file is ready, returns file content
 801  * with null byte appened.
 802  * Might return NULL in some error condition.
 803  */
 804 void * httpread_data_get(struct httpread *h)
 805 {
 806         return h->body ? h->body : "";
 807 }
 808
 809
 810 /* httpread_hdr_get -- When file is ready, returns header content
 811  * with null byte appended.
 812  * Might return NULL in some error condition.
 813  */
 814 char * httpread_hdr_get(struct httpread *h)
 815 {
 816         return h->hdr;
 817 }
 818
 819
 820 /* httpread_hdr_line_get -- When file is ready, returns pointer
 821  * to line within header content matching the given tag
 822  * (after the tag itself and any spaces/tabs).
 823  *
 824  * The tag should end with a colon for reliable matching.
 825  *
 826  * If not found, returns NULL;
 827  */
 828 char * httpread_hdr_line_get(struct httpread *h, const char *tag)
 829 {
 830         int tag_len = os_strlen(tag);
 831         char *hdr = h->hdr;
 832         hdr = os_strchr(hdr, '\n');
 833         if (hdr == NULL)
 834                 return NULL;
 835         hdr++;
 836         for (;;) {
 837                 if (!os_strncasecmp(hdr, tag, tag_len)) {
 838                         hdr += tag_len;
 839                         while (*hdr == ' ' || *hdr == '\t')
 840                                 hdr++;
 841                         return hdr;
 842                 }
 843                 hdr = os_strchr(hdr, '\n');
 844                 if (hdr == NULL)
 845                         return NULL;
 846                 hdr++;
 847         }
 848 }