pd.if.org Git - zpackage/blob - src/fetchurl.c

   1 #define _POSIX_C_SOURCE 200809L
   2
   3 #include <stdio.h>
   4 #include <sys/types.h>
   5 #include <sys/socket.h>
   6 #include <netinet/in.h>
   7 #include <netdb.h>
   8 #include <string.h>
   9 #include <strings.h>
  10 #include <stdlib.h>
  11 #include <unistd.h>
  12 #include <signal.h>
  13 #include <time.h>
  14 #include <sys/stat.h>
  15 #include <fcntl.h>
  16
  17 #include "tlse.h"
  18
  19 struct tls_uri {
  20         char *scheme;
  21         char *userinfo;
  22         char *host;
  23         char *port;
  24         char *path;
  25         char *query;
  26         char *fragment;
  27 };
  28 int tls_parse_uri(char *, struct tls_uri *);
  29 void tls_free_uri(struct tls_uri *);
  30
  31 int open_tcp_connection(char *host, int port);
  32
  33 /* if trustpolicy is 0, we just accept anything */
  34 int verify_trust(struct TLSContext *context, struct TLSCertificate **chain, int
  35                 len) {
  36         /* suppress unused */
  37         if (context || chain || len) {
  38                 return 0;
  39         }
  40
  41         return 0;
  42 }
  43
  44 static char hexchars[] = "0123456789abcdefABCDEF";
  45
  46 static void hex(char *dst, uint8_t *src, size_t len) {
  47         while (len--) {
  48                 dst[0] = hexchars[(src[0]>>4)&0xf];
  49                 dst[1] = hexchars[src[0]&0xf];
  50                 dst+=2;
  51                 src++;
  52         }
  53 }
  54
  55 #if 0
  56 static void hexbin(uint8_t *dst, unsigned char *src, size_t len) {
  57         size_t i;
  58         int x;
  59
  60         for (i=0; i<len; i+=2) {
  61                 sscanf((const char *)src+i, "%02x", &x);
  62                 dst[i/2] = x;
  63         }
  64 }
  65 #endif
  66
  67 char *my_getline(struct tls_buffer *b, int fd, size_t *size) {
  68         char *loc = 0;
  69         char buf[4096];
  70         ssize_t rv = 0;
  71
  72         while (b->error == 0) {
  73                 loc = memchr(b->buffer, '\n', b->len);
  74                 if (loc) {
  75                         *size = loc - b->buffer + 1;
  76                         return b->buffer;
  77                 } else {
  78                         rv = read(fd, buf, sizeof buf);
  79                         if (rv == -1) {
  80                                 return 0;
  81                         }
  82                         if (rv == 0) {
  83                                 break;
  84                         }
  85                         tls_buffer_append(b, buf, rv);
  86                 }
  87         }
  88         if (rv == 0) {
  89                 *size = b->len;
  90                 return b->buffer;
  91         }
  92         return 0;
  93 }
  94
  95 /*
  96  * We use a trust on first use policy.  The trust DB is a simple
  97  * file in /var/lib/zpm/known_hosts, or ~/.zpm/known_hosts, or ZPM_KNOWNHOSTS.
  98  * if -k is given, no verification is done
  99  */
 100 int verify_first(struct TLSContext *context, struct TLSCertificate **chain, int
 101                 certs) {
 102         int err;
 103         char *trustfile, *homedir = 0, *host, *fp;
 104         unsigned char certhash[65];
 105         int trustdb;
 106         struct tls_buffer tbuf;
 107
 108         char *line = 0;
 109         size_t len = 0;
 110
 111         if (certs == 0 || chain == 0) {
 112                 return 1;
 113         }
 114
 115         err = tls_certificate_is_valid(chain[0]);
 116         if (err) {
 117                 return err;
 118         }
 119
 120         if (context->sni) {
 121                 err = tls_certificate_valid_subject(chain[0], context->sni);
 122                 if (err) {
 123                         return err;
 124                 }
 125         }
 126
 127         hex(certhash, chain[0]->fp, 32);
 128         certhash[64] = 0;
 129
 130         trustfile = getenv("ZPM_KNOWNHOSTS");
 131         if (!trustfile) {
 132                 if (geteuid() == 0) {
 133                         trustfile = "/var/lib/zpm/known_hosts";
 134                 } else {
 135                         /* we could do this with a series of
 136                          * openat() calls instead of building
 137                          * up a string
 138                          */
 139                         trustfile = getenv("HOME");
 140                         if (!trustfile) {
 141                                 fprintf(stderr, "home = %s\n", trustfile);
 142                                 return 1;
 143                         }
 144                         len = snprintf(homedir, 0, "%s/.zpm/known_hosts", trustfile);
 145                         homedir = malloc(len+1);
 146                         if (!homedir) {
 147                                 return 1;
 148                         }
 149                         len = snprintf(homedir, len+1, "%s/.zpm/known_hosts", trustfile);
 150                         trustfile = homedir;
 151                 }
 152         }
 153         /* cert is valid on its face, so check against the trust db */
 154         trustdb = open(trustfile, O_RDWR|O_CREAT, 0600);
 155         if (trustdb == -1) {
 156                 fprintf(stderr, "cannot open trustdb %s: %s\n", trustfile, strerror(errno));
 157                 if (homedir) {
 158                         free(homedir);
 159                 }
 160                 return 1;
 161         }
 162
 163         if (homedir) {
 164                 free(homedir);
 165         }
 166
 167         len = 0;
 168         tls_buffer_init(&tbuf, 128);
 169         do {
 170                 char *off;
 171
 172                 tls_buffer_shift(&tbuf, len);
 173                 line = my_getline(&tbuf, trustdb, &len);
 174
 175                 if (!line || !len) {
 176                         break;
 177                 }
 178
 179                 fp = line;
 180                 while (isspace(*fp)) {
 181                         fp++;
 182                 }
 183                 if (*fp == '#') {
 184                         continue;
 185                 }
 186                 off = strchr(line, ':');
 187                 if (!off) {
 188                         continue;
 189                 }
 190                 host = off + 1;
 191                 *off = 0;
 192                 if (line[len-1] == '\n') {
 193                         line[len-1] = 0;
 194                 }
 195
 196                 if (strlen(fp) != 64) {
 197                         continue;
 198                 }
 199
 200                 if (len && line[len-1] == '\n') {
 201                         line[len-1] = 0;
 202                 }
 203
 204                 if (strcmp(context->sni, host) != 0) {
 205                         continue;
 206                 }
 207
 208                 int match = (memcmp(certhash, fp, 64) == 0);
 209
 210                 close(trustdb);
 211                 tls_buffer_free(&tbuf);
 212                 return match ? no_error : bad_certificate;
 213         } while (!tbuf.error);
 214
 215         /* got here, so we should be at EOF, so add this host to trust db */
 216         lseek(trustdb, 0, SEEK_END);
 217
 218         /* re-use the buffer so we only do one write */
 219         /* ignore errors, the cert is fine, we just can't update
 220          * the trustdb if there's errors here
 221          */
 222         tbuf.len = 0;
 223         tls_buffer_append(&tbuf, certhash, 64);
 224         tls_buffer_append_byte(&tbuf, ':');
 225         tls_buffer_append(&tbuf, context->sni, strlen(context->sni));
 226         tls_buffer_append_byte(&tbuf, '\n');
 227         write(trustdb, tbuf.buffer, tbuf.len);
 228         close(trustdb);
 229         tls_buffer_free(&tbuf);
 230
 231         return no_error;
 232 }
 233
 234 int verify_roots(struct TLSContext *context, struct TLSCertificate **chain, int
 235                 len) {
 236         int i, err;
 237
 238         if (chain) {
 239                 for (i = 0; i < len; i++) {
 240                         struct TLSCertificate *certificate = chain[i];
 241                         err = tls_certificate_is_valid(certificate);
 242                         if (err) {
 243                                 return err;
 244                         }
 245                 }
 246         }
 247
 248         err = tls_certificate_chain_is_valid(chain, len);
 249         if (err) {
 250                 return err;
 251         }
 252
 253         if (len > 0 && context->sni) {
 254                 err = tls_certificate_valid_subject(chain[0], context->sni);
 255                 if (err) {
 256                         return err;
 257                 }
 258         }
 259
 260         /* Perform certificate validation against ROOT CA */
 261         err = tls_certificate_chain_is_valid_root(context, chain, len);
 262         if (err) {
 263                 return err;
 264         }
 265
 266         return no_error;
 267 }
 268
 269 struct io {
 270         struct tls_buffer response;
 271         struct TLSContext *tls;
 272         int socket;
 273         int status_code;
 274         time_t last_modified;
 275         time_t date;
 276         size_t content_length;
 277         char *redirect;
 278 };
 279
 280 int month(char *m) {
 281         char *months[] = {"Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul",
 282                 "Aug", "Sep", "Oct", "Nov", "Dec" };
 283         int i;
 284
 285         for (i=0; i < 12; i++) {
 286                 if (!strncasecmp(m, months[i], 3)) {
 287                         return i+1;
 288                 }
 289         }
 290         return 0;
 291 }
 292
 293 /* Wed, 06 Feb 2019 10:06:05 GMT */
 294 time_t parse_date(char *d) {
 295         struct tm tm = { 0 };
 296         int rv;
 297
 298         int h, m, s, dom, Y;
 299         char M[4];
 300         rv = sscanf(d, "%*[a-zA-Z,] %d %s %d %d:%d:%d", &dom, M, &Y, &h, &m, &s);
 301         if (rv == 6) {
 302                 tm.tm_year = Y - 1900;
 303                 tm.tm_hour = h;
 304                 tm.tm_min = m;
 305                 tm.tm_sec = s;
 306                 tm.tm_mon = month(M)-1;
 307                 tm.tm_mday = dom;
 308
 309                 return mktime(&tm);
 310         }
 311         return -1;
 312 }
 313
 314 char *find_header(struct io *io, char *header, size_t *len) {
 315         char *eoh, *soh;
 316         size_t hlen;
 317
 318         *len = 0;
 319
 320         hlen = strlen(header);
 321         eoh = strstr(io->response.buffer, "\r\n\r\n");
 322         if (!eoh) {
 323                 return 0;
 324         }
 325         soh = io->response.buffer;
 326         do {
 327                 soh = strstr(soh, "\r\n");
 328                 if (soh == eoh) {
 329                         break;
 330                 }
 331                 soh += 2;
 332                 if (!memcmp(soh, header, hlen)) {
 333                         break;
 334                 }
 335         } while (soh < eoh);
 336
 337         if (soh >= eoh) {
 338                 return 0;
 339         }
 340         eoh = strstr(soh, "\r\n");
 341         soh += hlen;
 342         while (soh < eoh && isspace(*soh)) {
 343                 soh++;
 344         }
 345         *len = (eoh - soh);
 346         return soh;
 347 }
 348
 349 void parse_header(struct io *io) {
 350         char *s = io->response.buffer;
 351         int code = 0;
 352         char *hval;
 353         size_t hlen;
 354
 355         while (!isspace(*s)) {
 356                 s++;
 357         }
 358         while (isspace(*s)) {
 359                 s++;
 360         }
 361         code = strtol(s, 0, 10);
 362         io->status_code = code;
 363
 364         hval = find_header(io, "Date:", &hlen);
 365         if (hval) {
 366                 hval[hlen] = 0;
 367                 io->date = parse_date(hval);
 368                 hval[hlen] = '\r';
 369         }
 370         hval = find_header(io, "Last-Modified:", &hlen);
 371         if (hval) {
 372                 hval[hlen] = 0;
 373                 io->last_modified = parse_date(hval);
 374                 hval[hlen] = '\r';
 375         }
 376
 377         hval = find_header(io, "Content-Length:", &hlen);
 378         if (hval) {
 379                 hval[hlen] = 0;
 380                 io->content_length = strtoul(hval, 0, 10);
 381                 hval[hlen] = '\r';
 382         }
 383
 384         switch (code) {
 385                 case 301:
 386                 case 302:
 387                 case 303:
 388                 case 307:
 389                         hval = find_header(io, "Location:", &hlen);
 390                         if (hval) {
 391                                 io->redirect = strndup(hval, hlen);
 392                         }
 393                         break;
 394                 default:
 395                         break;
 396         }
 397
 398 }
 399
 400 ssize_t fill_buffer(struct io *io) {
 401         unsigned char buffer[4096];
 402         ssize_t ret;
 403
 404         if (io->tls) {
 405                 ret = tls_read(io->tls, buffer, sizeof buffer);
 406         } else {
 407                 ret = read(io->socket, buffer, sizeof buffer);
 408         }
 409
 410         if (ret > 0) {
 411                 tls_buffer_append(&io->response, buffer, ret);
 412         }
 413
 414         return ret;
 415 }
 416
 417 #if 0
 418 char *nextline(struct io *io) {
 419         char *eol = 0;;
 420
 421         eol = memchr(io->response.buffer, '\n', io.response.size);
 422         while (eol == 0) {
 423                 fill_buffer(io);
 424                 eol = memchr(io->response.buffer, '\n', io.response.size);
 425         }
 426         if (eol) {
 427
 428 }
 429 #endif
 430
 431 void append_header(struct tls_buffer *buf, char *header, char *val) {
 432         tls_buffer_append(buf, header, strlen(header));
 433         tls_buffer_append(buf, ": ", 2);
 434         tls_buffer_append(buf, val, strlen(val));
 435         tls_buffer_append(buf, "\r\n", 2);
 436 }
 437
 438 void append_timeheader(struct tls_buffer *buf, char *header, time_t ts) {
 439         char timestr[80];
 440         struct tm *tm;
 441
 442         tm = gmtime(&ts);
 443
 444         strftime(timestr, sizeof timestr, "%a, %d %b %Y %H:%M:%S GMT", tm);
 445         append_header(buf, header, timestr);
 446 }
 447
 448 static void pdots(int len, int ch, unsigned long was, unsigned long now,
 449                 unsigned long total) {
 450         was = len * was / total;
 451         if (now > total) {
 452                 now = total;
 453         }
 454         now = len * now / total;
 455         while (was++ < now) {
 456                 putc(ch,stderr);
 457         }
 458 }
 459
 460 static void fake_header(struct io *io, int fd) {
 461         struct stat st;
 462         int code = 200, rv;
 463         char *message, codestr[5], length[32];
 464         struct tls_buffer *hdr = &io->response;
 465
 466         if (fd == -1) {
 467                 switch (errno) {
 468                         case EACCES: code = 403; break;
 469                         case ENOENT: code = 404; break;
 470                         default: code = 500; break;
 471                 }
 472         } else {
 473                 rv = fstat(fd, &st);
 474                 if (rv == -1) {
 475                         code = 500;
 476                 }
 477         }
 478
 479         if (io->last_modified >= st.st_mtime) {
 480                 code = 304;
 481         }
 482
 483         switch (code) {
 484                 case 200: message = "OK"; break;
 485                 case 304: message = "Not Modified"; break;
 486                 case 403: message = "Forbidden"; break;
 487                 case 404: message = "Not Found"; break;
 488                 case 500: message = "Internal Server Error"; break;
 489                 default: break;
 490         }
 491         sprintf(codestr, "%0.3d ", code);
 492         tls_buffer_append(hdr, "HTTP/1.1 ", 9);
 493         tls_buffer_append(hdr, codestr, 4);
 494         tls_buffer_append_str(hdr, message);
 495         tls_buffer_append(hdr, "\r\n", 2);
 496
 497         append_timeheader(hdr, "Date", time(NULL));
 498         append_header(hdr, "Server", "zpm-fetchurl/0.9");
 499         if (code < 400) {
 500                 append_timeheader(hdr, "Last-Modified", st.st_mtime);
 501                 sprintf(length, "%zu", st.st_size);
 502                 append_header(hdr, "Content-Length", length);
 503         }
 504
 505         append_header(hdr, "Connection", "close");
 506         append_header(hdr, "Content-Type", "application/octet-stream");
 507         tls_buffer_append(hdr, "\r\n", 2);
 508 }
 509
 510 char *pathlast(char *path) {
 511         char *last = 0;
 512         size_t len = 0;
 513
 514         if (path == 0) {
 515                 return 0;
 516         }
 517
 518         while (*path == '/') {
 519                 path++;
 520         }
 521
 522         do {
 523                 last = path;
 524                 len = 0;
 525                 while (*path && *path != '/') {
 526                         path++;
 527                         len++;
 528                 }
 529                 while (*path == '/') {
 530                         path++;
 531                 }
 532         } while (*path);
 533
 534         if (len == 0) {
 535                 return 0;
 536         }
 537
 538         return strndup(last, len);
 539 }
 540
 541 static time_t file_mtime(char *path) {
 542         struct stat st;
 543         int rv;
 544
 545         rv = stat(path, &st);
 546         if (rv == -1) {
 547                 if (errno == ENOENT) {
 548                         return 0;
 549                 }
 550                 perror("stat failed:");
 551                 return -1;
 552         }
 553
 554         return st.st_mtime;
 555 }
 556
 557 int main(int ac, char *av[]) {
 558         int sockfd, port = -1, rv;
 559         ssize_t ret;
 560         int option;
 561 #if 0
 562         char msg[] = "GET %s HTTP/1.1\r\nHost: %s:%i\r\nConnection: close\r\n\r\n";
 563         char msg2[] = "GET %s HTTP/1.1\r\nHost: %s:%i\r\nLast-Modified: %s\r\nConnection: close\r\n\r\n";
 564         char msg_buffer[1024];
 565 #endif
 566         char *req_file = 0;
 567         char *host = 0;
 568         struct tls_uri uri = { 0 };
 569         char *outfile = 0;
 570         int raw = 0, head = 0;
 571         int out = 1; /* output file descriptor */
 572         int use_tls = 0;
 573         struct io io = { {0}, 0, -1, 0, 0, 0, 0, 0 };
 574         struct TLSContext *clientssl = 0;
 575         int failsilent = 0;
 576         char *lmfile = 0;
 577         int progressbar = 0;
 578         struct tls_buffer request;
 579         char lmtime[80];
 580         char *eoh = 0;
 581         size_t total = 0;
 582         size_t header_len;
 583         char *url = 0;
 584         int redirs = 0, redirlimit = 50, printstatus = 0;
 585         int verifypolicy = 1, calcoutfile = 0, ifnewer = 0;
 586
 587         ltc_mp = tfm_desc;
 588
 589         while ((option = getopt(ac, av, "o:OrIfz:np#R:SkK")) != -1) {
 590                 switch (option) {
 591                         case 'o': outfile = optarg; break;
 592                         case 'O': calcoutfile = 1; break;
 593                         case 'S': printstatus = 1; head = 1; break;
 594                         case 'k': verifypolicy = 0; break;
 595                         case 'K': verifypolicy = 2; break;
 596                         case 'I': head = 1;
 597                         case 'r': raw = 1; break;
 598                         case 'f': failsilent = 1; break;
 599                         case 'z': lmfile = optarg; break;
 600                         case 'n': ifnewer = 1; break;
 601                         case 'R': redirlimit = strtol(optarg, 0, 10); break;
 602                         case 'p':
 603                         case '#': progressbar = 1; break;
 604                         default:
 605                                   exit(EXIT_FAILURE);
 606                                   break;
 607                 }
 608         }
 609
 610         if (ac < optind) {
 611                 fprintf(stderr, "Usage: %s uri\n", av[0]);
 612                 exit(EXIT_FAILURE);
 613         }
 614
 615         url = strdup(av[optind]);
 616         if (!url) {
 617                 exit(EXIT_FAILURE);
 618         }
 619
 620         io.last_modified = 0;
 621
 622         if (calcoutfile && !outfile) {
 623                 tls_parse_uri(url, &uri);
 624                 outfile = pathlast(uri.path);
 625                 /* outfile leaks memory here, so if this
 626                  * were turned into a library function,
 627                  * we'd need to track it
 628                  */
 629                 if (!outfile) {
 630                         fprintf(stderr, "unable to determine outfile\n");
 631                         exit(EXIT_FAILURE);
 632                 }
 633         }
 634
 635         if (ifnewer && outfile && !lmfile) {
 636                 lmfile = outfile;
 637         }
 638
 639         if (lmfile) {
 640                 struct tm *mtime;
 641                 time_t ts;
 642
 643                 ts = file_mtime(lmfile);
 644
 645                 if (ts == -1) {
 646                         exit(EXIT_FAILURE);
 647                 } else if (ts != 0) {
 648                         io.last_modified = ts;
 649                         mtime = gmtime(&ts);
 650                         strftime(lmtime, sizeof lmtime, "%a, %d %b %Y %H:%M:%S GMT", mtime);
 651                 } else {
 652                         lmfile = 0;
 653                 }
 654         }
 655
 656         signal(SIGPIPE, SIG_IGN);
 657
 658         tls_buffer_init(&io.response, 0);
 659         tls_buffer_init(&request, 128);
 660
 661         while (redirs++ <= redirlimit) {
 662                 tls_free_uri(&uri);
 663                 io.response.len = 0;
 664                 request.len = 0;
 665                 eoh = 0;
 666
 667                 tls_parse_uri(url, &uri);
 668                 host = uri.host;
 669                 port = atoi(uri.port);
 670                 req_file = uri.path;
 671
 672                 /* construct request */
 673                 if (head) {
 674                         tls_buffer_append(&request, "HEAD ", 5);
 675                 } else {
 676                         tls_buffer_append(&request, "GET ", 4);
 677                 }
 678                 tls_buffer_append(&request, uri.path, strlen(uri.path));
 679                 tls_buffer_append(&request, " HTTP/1.1\r\n", 11);
 680
 681                 append_header(&request, "Host", host);
 682                 append_header(&request, "Connection", "close");
 683                 if (lmfile) {
 684                         append_header(&request, "If-Modified-Since", lmtime);
 685                 }
 686                 tls_buffer_append(&request, "\r\n", 2);
 687
 688                 if (!strcmp(uri.scheme, "https")) {
 689                         use_tls = 1;
 690
 691                         clientssl = tls_create_context(TLS_CLIENT, TLS_V12);
 692
 693                         /* optionally, we can set a certificate validation
 694                          * callback function if set_verify is not called, and
 695                          * root ca is set, `tls_default_verify` will be used
 696                          * (does exactly what `verify` does in this example)
 697                          */
 698                         if (verifypolicy == 2) {
 699                                 char *cert_path = 0;
 700                                 cert_path = getenv("ZPM_CERTFILE");
 701                                 if (!cert_path) {
 702                                         cert_path = "/var/lib/zpm/roots.pem";
 703                                 }
 704                                 rv = tls_load_root_file(clientssl, cert_path);
 705                                 if (rv == -1) {
 706                                         fprintf(stderr, "Error loading root certs\n");
 707                                         return 1;
 708                                 }
 709                                 tls_set_verify(clientssl, verify_roots);
 710                         } else if (verifypolicy == 1) {
 711                                 tls_set_verify(clientssl, verify_first);
 712                         } else {
 713                                 tls_set_verify(clientssl, verify_trust);
 714                         }
 715
 716                         if (!clientssl) {
 717                                 fprintf(stderr, "Error initializing client context\n");
 718                                 return -1;
 719                         }
 720                         tls_sni_set(clientssl, uri.host);
 721                         clientssl->sync = 1;
 722                         io.tls = clientssl;
 723                         sockfd = open_tcp_connection(host, port);
 724                         if (sockfd < 0) {
 725                                 perror("can't open connection");
 726                                 exit(EXIT_FAILURE);
 727                         }
 728                         tls_set_fd(clientssl, sockfd);
 729                         if ((rv = tls_connect(clientssl)) != 1) {
 730                                 fprintf(stderr, "Handshake Error %i\n", rv);
 731                                 return 1;
 732                         }
 733                         ret = tls_write(clientssl, request.buffer, request.len);
 734                 } else if (!strcmp(uri.scheme, "http")) {
 735                         sockfd = open_tcp_connection(host, port);
 736                         if (sockfd < 0) {
 737                                 perror("can't open connection");
 738                                 exit(EXIT_FAILURE);
 739                         }
 740                         ret = write(sockfd, request.buffer, request.len);
 741                 } else if (!strcmp(uri.scheme, "file")) {
 742                         sockfd = open(uri.path, O_RDONLY);
 743                         fake_header(&io, sockfd);
 744                         ret = 0;
 745                 } else {
 746                         fprintf(stderr, "scheme %s unknown\n", uri.scheme);
 747                         exit(EXIT_FAILURE);
 748                 }
 749
 750                 if (ret == -1) {
 751                         fprintf(stderr, "unable to write http request: %s\n", strerror(errno));
 752                         exit(EXIT_FAILURE);
 753                 }
 754
 755                 io.socket = sockfd;
 756
 757                 do {
 758                         if (io.response.len >= 4) {
 759                                 eoh = strstr(io.response.buffer, "\r\n\r\n");
 760                         }
 761                         if (!eoh) {
 762                                 ret = fill_buffer(&io);
 763                                 if (ret <= 0) {
 764                                         break;
 765                                 }
 766                         }
 767                 } while (!eoh);
 768
 769                 if (!eoh) {
 770                         /* never got (complet) header */
 771                         fprintf(stderr, "incomplete response to %s\n", av[optind]);
 772                         exit(EXIT_FAILURE);
 773                 }
 774
 775                 header_len = (size_t)(eoh - io.response.buffer) + 4;
 776                 parse_header(&io);
 777
 778                 switch (io.status_code) {
 779                         case 304:
 780                                 progressbar = 0;
 781                                 break;
 782                         case 301:
 783                         case 302:
 784                         case 303:
 785                         case 307:
 786                                 free(url);
 787                                 url = strdup(io.redirect);
 788                                 close(io.socket);
 789                                 continue;
 790                                 break;
 791                 }
 792
 793                 if (printstatus) {
 794                         printf("%d\n", io.status_code);
 795                         break;
 796                 }
 797
 798                 if (!raw) {
 799                         tls_buffer_shift(&io.response, header_len);
 800                 }
 801                 if (head) {
 802                         io.response.len -= 2;
 803                 }
 804
 805                 if (progressbar) {
 806                         if (io.content_length) {
 807                                 fprintf(stderr, "(%lu) ", io.content_length);
 808                         }
 809                 }
 810
 811                 if (outfile) {
 812                         out = open(outfile, O_WRONLY|O_CREAT, 0600);
 813                         if (out == -1) {
 814                                 perror("can't open output file:");
 815                                 exit(EXIT_FAILURE);
 816                         }
 817                 }
 818
 819                 do {
 820                         write(out, io.response.buffer, io.response.len);
 821                         ret = io.response.len;
 822                         io.response.len = 0;
 823
 824                         if (progressbar) {
 825                                 if (io.content_length) {
 826                                         pdots(50, '.', total, total+ret,
 827                                                         io.content_length);
 828                                 } else {
 829                                         putc('\r', stderr);
 830                                         fprintf(stderr, "%zu", total+ret);
 831                                 }
 832                                 total += ret;
 833                         }
 834                         if (head) {
 835                                 break;
 836                         }
 837                         ret = fill_buffer(&io);
 838                 } while (ret > 0);
 839
 840                 if (ret < 0) {
 841                         fprintf(stderr, "%s read error %zd\n", uri.scheme, ret);
 842                 }
 843                 struct timespec ts[2];
 844                 ts[0].tv_sec = 0; ts[0].tv_nsec = UTIME_OMIT;
 845                 ts[1].tv_sec = io.last_modified;
 846                 ts[1].tv_nsec = 0;
 847
 848                 futimens(out, ts);
 849                 close(out);
 850                 tls_buffer_free(&io.response);
 851                 break;
 852         }
 853
 854         if (use_tls) {
 855                 tls_shutdown(clientssl);
 856                 tls_free(clientssl);
 857         }
 858
 859         close(sockfd);
 860         if (progressbar && io.status_code == 200) {
 861                 fprintf(stderr, "(%lu)", total);
 862                 putc('\n',stderr);
 863         }
 864
 865         return io.status_code < 400 ? 0 : EXIT_FAILURE;
 866 }