send-pack.c

   1 #include "builtin.h"
   2 #include "commit.h"
   3 #include "refs.h"
   4 #include "pkt-line.h"
   5 #include "sideband.h"
   6 #include "run-command.h"
   7 #include "remote.h"
   8 #include "connect.h"
   9 #include "send-pack.h"
  10 #include "quote.h"
  11 #include "transport.h"
  12 #include "version.h"
  13 #include "sha1-array.h"
  14 #include "gpg-interface.h"
  15 #include "cache.h"
  16
  17 int option_parse_push_signed(const struct option *opt,
  18                              const char *arg, int unset)
  19 {
  20         if (unset) {
  21                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;
  22                 return 0;
  23         }
  24         switch (git_parse_maybe_bool(arg)) {
  25         case 1:
  26                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_ALWAYS;
  27                 return 0;
  28         case 0:
  29                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;
  30                 return 0;
  31         }
  32         if (!strcasecmp("if-asked", arg)) {
  33                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_IF_ASKED;
  34                 return 0;
  35         }
  36         die("bad %s argument: %s", opt->long_name, arg);
  37 }
  38
  39 static void feed_object(const unsigned char *sha1, FILE *fh, int negative)
  40 {
  41         if (negative && !has_sha1_file(sha1))
  42                 return;
  43
  44         if (negative)
  45                 putc('^', fh);
  46         fputs(sha1_to_hex(sha1), fh);
  47         putc('\n', fh);
  48 }
  49
  50 /*
  51  * Make a pack stream and spit it out into file descriptor fd
  52  */
  53 static int pack_objects(int fd, struct ref *refs, struct sha1_array *extra, struct send_pack_args *args)
  54 {
  55         /*
  56          * The child becomes pack-objects --revs; we feed
  57          * the revision parameters to it via its stdin and
  58          * let its stdout go back to the other end.
  59          */
  60         const char *argv[] = {
  61                 "pack-objects",
  62                 "--all-progress-implied",
  63                 "--revs",
  64                 "--stdout",
  65                 NULL,
  66                 NULL,
  67                 NULL,
  68                 NULL,
  69                 NULL,
  70                 NULL,
  71         };
  72         struct child_process po = CHILD_PROCESS_INIT;
  73         FILE *po_in;
  74         int i;
  75         int rc;
  76
  77         i = 4;
  78         if (args->use_thin_pack)
  79                 argv[i++] = "--thin";
  80         if (args->use_ofs_delta)
  81                 argv[i++] = "--delta-base-offset";
  82         if (args->quiet || !args->progress)
  83                 argv[i++] = "-q";
  84         if (args->progress)
  85                 argv[i++] = "--progress";
  86         if (is_repository_shallow())
  87                 argv[i++] = "--shallow";
  88         po.argv = argv;
  89         po.in = -1;
  90         po.out = args->stateless_rpc ? -1 : fd;
  91         po.git_cmd = 1;
  92         if (start_command(&po))
  93                 die_errno("git pack-objects failed");
  94
  95         /*
  96          * We feed the pack-objects we just spawned with revision
  97          * parameters by writing to the pipe.
  98          */
  99         po_in = xfdopen(po.in, "w");
 100         for (i = 0; i < extra->nr; i++)
 101                 feed_object(extra->sha1[i], po_in, 1);
 102
 103         while (refs) {
 104                 if (!is_null_oid(&refs->old_oid))
 105                         feed_object(refs->old_oid.hash, po_in, 1);
 106                 if (!is_null_oid(&refs->new_oid))
 107                         feed_object(refs->new_oid.hash, po_in, 0);
 108                 refs = refs->next;
 109         }
 110
 111         fflush(po_in);
 112         if (ferror(po_in))
 113                 die_errno("error writing to pack-objects");
 114         fclose(po_in);
 115
 116         if (args->stateless_rpc) {
 117                 char *buf = xmalloc(LARGE_PACKET_MAX);
 118                 while (1) {
 119                         ssize_t n = xread(po.out, buf, LARGE_PACKET_MAX);
 120                         if (n <= 0)
 121                                 break;
 122                         send_sideband(fd, -1, buf, n, LARGE_PACKET_MAX);
 123                 }
 124                 free(buf);
 125                 close(po.out);
 126                 po.out = -1;
 127         }
 128
 129         rc = finish_command(&po);
 130         if (rc) {
 131                 /*
 132                  * For a normal non-zero exit, we assume pack-objects wrote
 133                  * something useful to stderr. For death by signal, though,
 134                  * we should mention it to the user. The exception is SIGPIPE
 135                  * (141), because that's a normal occurence if the remote end
 136                  * hangs up (and we'll report that by trying to read the unpack
 137                  * status).
 138                  */
 139                 if (rc > 128 && rc != 141)
 140                         error("pack-objects died of signal %d", rc - 128);
 141                 return -1;
 142         }
 143         return 0;
 144 }
 145
 146 static int receive_unpack_status(int in)
 147 {
 148         const char *line = packet_read_line(in, NULL);
 149         if (!skip_prefix(line, "unpack ", &line))
 150                 return error(_("unable to parse remote unpack status: %s"), line);
 151         if (strcmp(line, "ok"))
 152                 return error(_("remote unpack failed: %s"), line);
 153         return 0;
 154 }
 155
 156 static int receive_status(int in, struct ref *refs)
 157 {
 158         struct ref *hint;
 159         int ret;
 160
 161         hint = NULL;
 162         ret = receive_unpack_status(in);
 163         while (1) {
 164                 char *refname;
 165                 char *msg;
 166                 char *line = packet_read_line(in, NULL);
 167                 if (!line)
 168                         break;
 169                 if (!starts_with(line, "ok ") && !starts_with(line, "ng ")) {
 170                         error("invalid ref status from remote: %s", line);
 171                         ret = -1;
 172                         break;
 173                 }
 174
 175                 refname = line + 3;
 176                 msg = strchr(refname, ' ');
 177                 if (msg)
 178                         *msg++ = '\0';
 179
 180                 /* first try searching at our hint, falling back to all refs */
 181                 if (hint)
 182                         hint = find_ref_by_name(hint, refname);
 183                 if (!hint)
 184                         hint = find_ref_by_name(refs, refname);
 185                 if (!hint) {
 186                         warning("remote reported status on unknown ref: %s",
 187                                         refname);
 188                         continue;
 189                 }
 190                 if (hint->status != REF_STATUS_EXPECTING_REPORT) {
 191                         warning("remote reported status on unexpected ref: %s",
 192                                         refname);
 193                         continue;
 194                 }
 195
 196                 if (line[0] == 'o' && line[1] == 'k')
 197                         hint->status = REF_STATUS_OK;
 198                 else {
 199                         hint->status = REF_STATUS_REMOTE_REJECT;
 200                         ret = -1;
 201                 }
 202                 hint->remote_status = xstrdup_or_null(msg);
 203                 /* start our next search from the next ref */
 204                 hint = hint->next;
 205         }
 206         return ret;
 207 }
 208
 209 static int sideband_demux(int in, int out, void *data)
 210 {
 211         int *fd = data, ret;
 212 #ifdef NO_PTHREADS
 213         close(fd[1]);
 214 #endif
 215         ret = recv_sideband("send-pack", fd[0], out);
 216         close(out);
 217         return ret;
 218 }
 219
 220 static int advertise_shallow_grafts_cb(const struct commit_graft *graft, void *cb)
 221 {
 222         struct strbuf *sb = cb;
 223         if (graft->nr_parent == -1)
 224                 packet_buf_write(sb, "shallow %s\n", oid_to_hex(&graft->oid));
 225         return 0;
 226 }
 227
 228 static void advertise_shallow_grafts_buf(struct strbuf *sb)
 229 {
 230         if (!is_repository_shallow())
 231                 return;
 232         for_each_commit_graft(advertise_shallow_grafts_cb, sb);
 233 }
 234
 235 #define CHECK_REF_NO_PUSH -1
 236 #define CHECK_REF_STATUS_REJECTED -2
 237 #define CHECK_REF_UPTODATE -3
 238 static int check_to_send_update(const struct ref *ref, const struct send_pack_args *args)
 239 {
 240         if (!ref->peer_ref && !args->send_mirror)
 241                 return CHECK_REF_NO_PUSH;
 242
 243         /* Check for statuses set by set_ref_status_for_push() */
 244         switch (ref->status) {
 245         case REF_STATUS_REJECT_NONFASTFORWARD:
 246         case REF_STATUS_REJECT_ALREADY_EXISTS:
 247         case REF_STATUS_REJECT_FETCH_FIRST:
 248         case REF_STATUS_REJECT_NEEDS_FORCE:
 249         case REF_STATUS_REJECT_STALE:
 250         case REF_STATUS_REJECT_NODELETE:
 251                 return CHECK_REF_STATUS_REJECTED;
 252         case REF_STATUS_UPTODATE:
 253                 return CHECK_REF_UPTODATE;
 254         default:
 255                 return 0;
 256         }
 257 }
 258
 259 /*
 260  * the beginning of the next line, or the end of buffer.
 261  *
 262  * NEEDSWORK: perhaps move this to git-compat-util.h or somewhere and
 263  * convert many similar uses found by "git grep -A4 memchr".
 264  */
 265 static const char *next_line(const char *line, size_t len)
 266 {
 267         const char *nl = memchr(line, '\n', len);
 268         if (!nl)
 269                 return line + len; /* incomplete line */
 270         return nl + 1;
 271 }
 272
 273 static int generate_push_cert(struct strbuf *req_buf,
 274                               const struct ref *remote_refs,
 275                               struct send_pack_args *args,
 276                               const char *cap_string,
 277                               const char *push_cert_nonce)
 278 {
 279         const struct ref *ref;
 280         struct string_list_item *item;
 281         char *signing_key = xstrdup(get_signing_key());
 282         const char *cp, *np;
 283         struct strbuf cert = STRBUF_INIT;
 284         int update_seen = 0;
 285
 286         strbuf_addstr(&cert, "certificate version 0.1\n");
 287         strbuf_addf(&cert, "pusher %s ", signing_key);
 288         datestamp(&cert);
 289         strbuf_addch(&cert, '\n');
 290         if (args->url && *args->url) {
 291                 char *anon_url = transport_anonymize_url(args->url);
 292                 strbuf_addf(&cert, "pushee %s\n", anon_url);
 293                 free(anon_url);
 294         }
 295         if (push_cert_nonce[0])
 296                 strbuf_addf(&cert, "nonce %s\n", push_cert_nonce);
 297         if (args->push_options)
 298                 for_each_string_list_item(item, args->push_options)
 299                         strbuf_addf(&cert, "push-option %s\n", item->string);
 300         strbuf_addstr(&cert, "\n");
 301
 302         for (ref = remote_refs; ref; ref = ref->next) {
 303                 if (check_to_send_update(ref, args) < 0)
 304                         continue;
 305                 update_seen = 1;
 306                 strbuf_addf(&cert, "%s %s %s\n",
 307                             oid_to_hex(&ref->old_oid),
 308                             oid_to_hex(&ref->new_oid),
 309                             ref->name);
 310         }
 311         if (!update_seen)
 312                 goto free_return;
 313
 314         if (sign_buffer(&cert, &cert, signing_key))
 315                 die(_("failed to sign the push certificate"));
 316
 317         packet_buf_write(req_buf, "push-cert%c%s", 0, cap_string);
 318         for (cp = cert.buf; cp < cert.buf + cert.len; cp = np) {
 319                 np = next_line(cp, cert.buf + cert.len - cp);
 320                 packet_buf_write(req_buf,
 321                                  "%.*s", (int)(np - cp), cp);
 322         }
 323         packet_buf_write(req_buf, "push-cert-end\n");
 324
 325 free_return:
 326         free(signing_key);
 327         strbuf_release(&cert);
 328         return update_seen;
 329 }
 330
 331
 332 static int atomic_push_failure(struct send_pack_args *args,
 333                                struct ref *remote_refs,
 334                                struct ref *failing_ref)
 335 {
 336         struct ref *ref;
 337         /* Mark other refs as failed */
 338         for (ref = remote_refs; ref; ref = ref->next) {
 339                 if (!ref->peer_ref && !args->send_mirror)
 340                         continue;
 341
 342                 switch (ref->status) {
 343                 case REF_STATUS_EXPECTING_REPORT:
 344                         ref->status = REF_STATUS_ATOMIC_PUSH_FAILED;
 345                         continue;
 346                 default:
 347                         break; /* do nothing */
 348                 }
 349         }
 350         return error("atomic push failed for ref %s. status: %d\n",
 351                      failing_ref->name, failing_ref->status);
 352 }
 353
 354 #define NONCE_LEN_LIMIT 256
 355
 356 static void reject_invalid_nonce(const char *nonce, int len)
 357 {
 358         int i = 0;
 359
 360         if (NONCE_LEN_LIMIT <= len)
 361                 die("the receiving end asked to sign an invalid nonce <%.*s>",
 362                     len, nonce);
 363
 364         for (i = 0; i < len; i++) {
 365                 int ch = nonce[i] & 0xFF;
 366                 if (isalnum(ch) ||
 367                     ch == '-' || ch == '.' ||
 368                     ch == '/' || ch == '+' ||
 369                     ch == '=' || ch == '_')
 370                         continue;
 371                 die("the receiving end asked to sign an invalid nonce <%.*s>",
 372                     len, nonce);
 373         }
 374 }
 375
 376 int send_pack(struct send_pack_args *args,
 377               int fd[], struct child_process *conn,
 378               struct ref *remote_refs,
 379               struct sha1_array *extra_have)
 380 {
 381         int in = fd[0];
 382         int out = fd[1];
 383         struct strbuf req_buf = STRBUF_INIT;
 384         struct strbuf cap_buf = STRBUF_INIT;
 385         struct ref *ref;
 386         int need_pack_data = 0;
 387         int allow_deleting_refs = 0;
 388         int status_report = 0;
 389         int use_sideband = 0;
 390         int quiet_supported = 0;
 391         int agent_supported = 0;
 392         int use_atomic = 0;
 393         int atomic_supported = 0;
 394         int use_push_options = 0;
 395         int push_options_supported = 0;
 396         unsigned cmds_sent = 0;
 397         int ret;
 398         struct async demux;
 399         const char *push_cert_nonce = NULL;
 400
 401         /* Does the other end support the reporting? */
 402         if (server_supports("report-status"))
 403                 status_report = 1;
 404         if (server_supports("delete-refs"))
 405                 allow_deleting_refs = 1;
 406         if (server_supports("ofs-delta"))
 407                 args->use_ofs_delta = 1;
 408         if (server_supports("side-band-64k"))
 409                 use_sideband = 1;
 410         if (server_supports("quiet"))
 411                 quiet_supported = 1;
 412         if (server_supports("agent"))
 413                 agent_supported = 1;
 414         if (server_supports("no-thin"))
 415                 args->use_thin_pack = 0;
 416         if (server_supports("atomic"))
 417                 atomic_supported = 1;
 418         if (server_supports("push-options"))
 419                 push_options_supported = 1;
 420
 421         if (args->push_cert != SEND_PACK_PUSH_CERT_NEVER) {
 422                 int len;
 423                 push_cert_nonce = server_feature_value("push-cert", &len);
 424                 if (push_cert_nonce) {
 425                         reject_invalid_nonce(push_cert_nonce, len);
 426                         push_cert_nonce = xmemdupz(push_cert_nonce, len);
 427                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_ALWAYS) {
 428                         die(_("the receiving end does not support --signed push"));
 429                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_IF_ASKED) {
 430                         warning(_("not sending a push certificate since the"
 431                                   " receiving end does not support --signed"
 432                                   " push"));
 433                 }
 434         }
 435
 436         if (!remote_refs) {
 437                 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
 438                         "Perhaps you should specify a branch such as 'master'.\n");
 439                 return 0;
 440         }
 441         if (args->atomic && !atomic_supported)
 442                 die(_("the receiving end does not support --atomic push"));
 443
 444         use_atomic = atomic_supported && args->atomic;
 445
 446         if (args->push_options && !push_options_supported)
 447                 die(_("the receiving end does not support push options"));
 448
 449         use_push_options = push_options_supported && args->push_options;
 450
 451         if (status_report)
 452                 strbuf_addstr(&cap_buf, " report-status");
 453         if (use_sideband)
 454                 strbuf_addstr(&cap_buf, " side-band-64k");
 455         if (quiet_supported && (args->quiet || !args->progress))
 456                 strbuf_addstr(&cap_buf, " quiet");
 457         if (use_atomic)
 458                 strbuf_addstr(&cap_buf, " atomic");
 459         if (use_push_options)
 460                 strbuf_addstr(&cap_buf, " push-options");
 461         if (agent_supported)
 462                 strbuf_addf(&cap_buf, " agent=%s", git_user_agent_sanitized());
 463
 464         /*
 465          * NEEDSWORK: why does delete-refs have to be so specific to
 466          * send-pack machinery that set_ref_status_for_push() cannot
 467          * set this bit for us???
 468          */
 469         for (ref = remote_refs; ref; ref = ref->next)
 470                 if (ref->deletion && !allow_deleting_refs)
 471                         ref->status = REF_STATUS_REJECT_NODELETE;
 472
 473         if (!args->dry_run)
 474                 advertise_shallow_grafts_buf(&req_buf);
 475
 476         if (!args->dry_run && push_cert_nonce)
 477                 cmds_sent = generate_push_cert(&req_buf, remote_refs, args,
 478                                                cap_buf.buf, push_cert_nonce);
 479
 480         /*
 481          * Clear the status for each ref and see if we need to send
 482          * the pack data.
 483          */
 484         for (ref = remote_refs; ref; ref = ref->next) {
 485                 switch (check_to_send_update(ref, args)) {
 486                 case 0: /* no error */
 487                         break;
 488                 case CHECK_REF_STATUS_REJECTED:
 489                         /*
 490                          * When we know the server would reject a ref update if
 491                          * we were to send it and we're trying to send the refs
 492                          * atomically, abort the whole operation.
 493                          */
 494                         if (use_atomic)
 495                                 return atomic_push_failure(args, remote_refs, ref);
 496                         /* Fallthrough for non atomic case. */
 497                 default:
 498                         continue;
 499                 }
 500                 if (!ref->deletion)
 501                         need_pack_data = 1;
 502
 503                 if (args->dry_run || !status_report)
 504                         ref->status = REF_STATUS_OK;
 505                 else
 506                         ref->status = REF_STATUS_EXPECTING_REPORT;
 507         }
 508
 509         /*
 510          * Finally, tell the other end!
 511          */
 512         for (ref = remote_refs; ref; ref = ref->next) {
 513                 char *old_hex, *new_hex;
 514
 515                 if (args->dry_run || push_cert_nonce)
 516                         continue;
 517
 518                 if (check_to_send_update(ref, args) < 0)
 519                         continue;
 520
 521                 old_hex = oid_to_hex(&ref->old_oid);
 522                 new_hex = oid_to_hex(&ref->new_oid);
 523                 if (!cmds_sent) {
 524                         packet_buf_write(&req_buf,
 525                                          "%s %s %s%c%s",
 526                                          old_hex, new_hex, ref->name, 0,
 527                                          cap_buf.buf);
 528                         cmds_sent = 1;
 529                 } else {
 530                         packet_buf_write(&req_buf, "%s %s %s",
 531                                          old_hex, new_hex, ref->name);
 532                 }
 533         }
 534
 535         if (use_push_options) {
 536                 struct string_list_item *item;
 537
 538                 packet_buf_flush(&req_buf);
 539                 for_each_string_list_item(item, args->push_options)
 540                         packet_buf_write(&req_buf, "%s", item->string);
 541         }
 542
 543         if (args->stateless_rpc) {
 544                 if (!args->dry_run && (cmds_sent || is_repository_shallow())) {
 545                         packet_buf_flush(&req_buf);
 546                         send_sideband(out, -1, req_buf.buf, req_buf.len, LARGE_PACKET_MAX);
 547                 }
 548         } else {
 549                 write_or_die(out, req_buf.buf, req_buf.len);
 550                 packet_flush(out);
 551         }
 552         strbuf_release(&req_buf);
 553         strbuf_release(&cap_buf);
 554
 555         if (use_sideband && cmds_sent) {
 556                 memset(&demux, 0, sizeof(demux));
 557                 demux.proc = sideband_demux;
 558                 demux.data = fd;
 559                 demux.out = -1;
 560                 demux.isolate_sigpipe = 1;
 561                 if (start_async(&demux))
 562                         die("send-pack: unable to fork off sideband demultiplexer");
 563                 in = demux.out;
 564         }
 565
 566         if (need_pack_data && cmds_sent) {
 567                 if (pack_objects(out, remote_refs, extra_have, args) < 0) {
 568                         for (ref = remote_refs; ref; ref = ref->next)
 569                                 ref->status = REF_STATUS_NONE;
 570                         if (args->stateless_rpc)
 571                                 close(out);
 572                         if (git_connection_is_socket(conn))
 573                                 shutdown(fd[0], SHUT_WR);
 574
 575                         /*
 576                          * Do not even bother with the return value; we know we
 577                          * are failing, and just want the error() side effects.
 578                          */
 579                         if (status_report)
 580                                 receive_unpack_status(in);
 581
 582                         if (use_sideband) {
 583                                 close(demux.out);
 584                                 finish_async(&demux);
 585                         }
 586                         fd[1] = -1;
 587                         return -1;
 588                 }
 589                 if (!args->stateless_rpc)
 590                         /* Closed by pack_objects() via start_command() */
 591                         fd[1] = -1;
 592         }
 593         if (args->stateless_rpc && cmds_sent)
 594                 packet_flush(out);
 595
 596         if (status_report && cmds_sent)
 597                 ret = receive_status(in, remote_refs);
 598         else
 599                 ret = 0;
 600         if (args->stateless_rpc)
 601                 packet_flush(out);
 602
 603         if (use_sideband && cmds_sent) {
 604                 close(demux.out);
 605                 if (finish_async(&demux)) {
 606                         error("error in sideband demultiplexer");
 607                         ret = -1;
 608                 }
 609         }
 610
 611         if (ret < 0)
 612                 return ret;
 613
 614         if (args->porcelain)
 615                 return 0;
 616
 617         for (ref = remote_refs; ref; ref = ref->next) {
 618                 switch (ref->status) {
 619                 case REF_STATUS_NONE:
 620                 case REF_STATUS_UPTODATE:
 621                 case REF_STATUS_OK:
 622                         break;
 623                 default:
 624                         return -1;
 625                 }
 626         }
 627         return 0;
 628 }