send-pack.c

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