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