send-pack.c

   1 #include "builtin.h"
   2 #include "config.h"
   3 #include "commit.h"
   4 #include "refs.h"
   5 #include "pkt-line.h"
   6 #include "sideband.h"
   7 #include "run-command.h"
   8 #include "remote.h"
   9 #include "connect.h"
  10 #include "send-pack.h"
  11 #include "quote.h"
  12 #include "transport.h"
  13 #include "version.h"
  14 #include "sha1-array.h"
  15 #include "gpg-interface.h"
  16 #include "cache.h"
  17
  18 int option_parse_push_signed(const struct option *opt,
  19                              const char *arg, int unset)
  20 {
  21         if (unset) {
  22                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;
  23                 return 0;
  24         }
  25         switch (git_parse_maybe_bool(arg)) {
  26         case 1:
  27                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_ALWAYS;
  28                 return 0;
  29         case 0:
  30                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;
  31                 return 0;
  32         }
  33         if (!strcasecmp("if-asked", arg)) {
  34                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_IF_ASKED;
  35                 return 0;
  36         }
  37         die("bad %s argument: %s", opt->long_name, arg);
  38 }
  39
  40 static void feed_object(const unsigned char *sha1, FILE *fh, int negative)
  41 {
  42         if (negative && !has_sha1_file(sha1))
  43                 return;
  44
  45         if (negative)
  46                 putc('^', fh);
  47         fputs(sha1_to_hex(sha1), fh);
  48         putc('\n', fh);
  49 }
  50
  51 /*
  52  * Make a pack stream and spit it out into file descriptor fd
  53  */
  54 static int pack_objects(int fd, struct ref *refs, struct oid_array *extra, struct send_pack_args *args)
  55 {
  56         /*
  57          * The child becomes pack-objects --revs; we feed
  58          * the revision parameters to it via its stdin and
  59          * let its stdout go back to the other end.
  60          */
  61         const char *argv[] = {
  62                 "pack-objects",
  63                 "--all-progress-implied",
  64                 "--revs",
  65                 "--stdout",
  66                 NULL,
  67                 NULL,
  68                 NULL,
  69                 NULL,
  70                 NULL,
  71                 NULL,
  72         };
  73         struct child_process po = CHILD_PROCESS_INIT;
  74         FILE *po_in;
  75         int i;
  76         int rc;
  77
  78         i = 4;
  79         if (args->use_thin_pack)
  80                 argv[i++] = "--thin";
  81         if (args->use_ofs_delta)
  82                 argv[i++] = "--delta-base-offset";
  83         if (args->quiet || !args->progress)
  84                 argv[i++] = "-q";
  85         if (args->progress)
  86                 argv[i++] = "--progress";
  87         if (is_repository_shallow())
  88                 argv[i++] = "--shallow";
  89         po.argv = argv;
  90         po.in = -1;
  91         po.out = args->stateless_rpc ? -1 : fd;
  92         po.git_cmd = 1;
  93         if (start_command(&po))
  94                 die_errno("git pack-objects failed");
  95
  96         /*
  97          * We feed the pack-objects we just spawned with revision
  98          * parameters by writing to the pipe.
  99          */
 100         po_in = xfdopen(po.in, "w");
 101         for (i = 0; i < extra->nr; i++)
 102                 feed_object(extra->oid[i].hash, po_in, 1);
 103
 104         while (refs) {
 105                 if (!is_null_oid(&refs->old_oid))
 106                         feed_object(refs->old_oid.hash, po_in, 1);
 107                 if (!is_null_oid(&refs->new_oid))
 108                         feed_object(refs->new_oid.hash, po_in, 0);
 109                 refs = refs->next;
 110         }
 111
 112         fflush(po_in);
 113         if (ferror(po_in))
 114                 die_errno("error writing to pack-objects");
 115         fclose(po_in);
 116
 117         if (args->stateless_rpc) {
 118                 char *buf = xmalloc(LARGE_PACKET_MAX);
 119                 while (1) {
 120                         ssize_t n = xread(po.out, buf, LARGE_PACKET_MAX);
 121                         if (n <= 0)
 122                                 break;
 123                         send_sideband(fd, -1, buf, n, LARGE_PACKET_MAX);
 124                 }
 125                 free(buf);
 126                 close(po.out);
 127                 po.out = -1;
 128         }
 129
 130         rc = finish_command(&po);
 131         if (rc) {
 132                 /*
 133                  * For a normal non-zero exit, we assume pack-objects wrote
 134                  * something useful to stderr. For death by signal, though,
 135                  * we should mention it to the user. The exception is SIGPIPE
 136                  * (141), because that's a normal occurrence if the remote end
 137                  * hangs up (and we'll report that by trying to read the unpack
 138                  * status).
 139                  */
 140                 if (rc > 128 && rc != 141)
 141                         error("pack-objects died of signal %d", rc - 128);
 142                 return -1;
 143         }
 144         return 0;
 145 }
 146
 147 static int receive_unpack_status(int in)
 148 {
 149         const char *line = packet_read_line(in, NULL);
 150         if (!skip_prefix(line, "unpack ", &line))
 151                 return error(_("unable to parse remote unpack status: %s"), line);
 152         if (strcmp(line, "ok"))
 153                 return error(_("remote unpack failed: %s"), line);
 154         return 0;
 155 }
 156
 157 static int receive_status(int in, struct ref *refs)
 158 {
 159         struct ref *hint;
 160         int ret;
 161
 162         hint = NULL;
 163         ret = receive_unpack_status(in);
 164         while (1) {
 165                 char *refname;
 166                 char *msg;
 167                 char *line = packet_read_line(in, NULL);
 168                 if (!line)
 169                         break;
 170                 if (!starts_with(line, "ok ") && !starts_with(line, "ng ")) {
 171                         error("invalid ref status from remote: %s", line);
 172                         ret = -1;
 173                         break;
 174                 }
 175
 176                 refname = line + 3;
 177                 msg = strchr(refname, ' ');
 178                 if (msg)
 179                         *msg++ = '\0';
 180
 181                 /* first try searching at our hint, falling back to all refs */
 182                 if (hint)
 183                         hint = find_ref_by_name(hint, refname);
 184                 if (!hint)
 185                         hint = find_ref_by_name(refs, refname);
 186                 if (!hint) {
 187                         warning("remote reported status on unknown ref: %s",
 188                                         refname);
 189                         continue;
 190                 }
 191                 if (hint->status != REF_STATUS_EXPECTING_REPORT) {
 192                         warning("remote reported status on unexpected ref: %s",
 193                                         refname);
 194                         continue;
 195                 }
 196
 197                 if (line[0] == 'o' && line[1] == 'k')
 198                         hint->status = REF_STATUS_OK;
 199                 else {
 200                         hint->status = REF_STATUS_REMOTE_REJECT;
 201                         ret = -1;
 202                 }
 203                 hint->remote_status = xstrdup_or_null(msg);
 204                 /* start our next search from the next ref */
 205                 hint = hint->next;
 206         }
 207         return ret;
 208 }
 209
 210 static int sideband_demux(int in, int out, void *data)
 211 {
 212         int *fd = data, ret;
 213 #ifdef NO_PTHREADS
 214         close(fd[1]);
 215 #endif
 216         ret = recv_sideband("send-pack", fd[0], out);
 217         close(out);
 218         return ret;
 219 }
 220
 221 static int advertise_shallow_grafts_cb(const struct commit_graft *graft, void *cb)
 222 {
 223         struct strbuf *sb = cb;
 224         if (graft->nr_parent == -1)
 225                 packet_buf_write(sb, "shallow %s\n", oid_to_hex(&graft->oid));
 226         return 0;
 227 }
 228
 229 static void advertise_shallow_grafts_buf(struct strbuf *sb)
 230 {
 231         if (!is_repository_shallow())
 232                 return;
 233         for_each_commit_graft(advertise_shallow_grafts_cb, sb);
 234 }
 235
 236 #define CHECK_REF_NO_PUSH -1
 237 #define CHECK_REF_STATUS_REJECTED -2
 238 #define CHECK_REF_UPTODATE -3
 239 static int check_to_send_update(const struct ref *ref, const struct send_pack_args *args)
 240 {
 241         if (!ref->peer_ref && !args->send_mirror)
 242                 return CHECK_REF_NO_PUSH;
 243
 244         /* Check for statuses set by set_ref_status_for_push() */
 245         switch (ref->status) {
 246         case REF_STATUS_REJECT_NONFASTFORWARD:
 247         case REF_STATUS_REJECT_ALREADY_EXISTS:
 248         case REF_STATUS_REJECT_FETCH_FIRST:
 249         case REF_STATUS_REJECT_NEEDS_FORCE:
 250         case REF_STATUS_REJECT_STALE:
 251         case REF_STATUS_REJECT_NODELETE:
 252                 return CHECK_REF_STATUS_REJECTED;
 253         case REF_STATUS_UPTODATE:
 254                 return CHECK_REF_UPTODATE;
 255         default:
 256                 return 0;
 257         }
 258 }
 259
 260 /*
 261  * the beginning of the next line, or the end of buffer.
 262  *
 263  * NEEDSWORK: perhaps move this to git-compat-util.h or somewhere and
 264  * convert many similar uses found by "git grep -A4 memchr".
 265  */
 266 static const char *next_line(const char *line, size_t len)
 267 {
 268         const char *nl = memchr(line, '\n', len);
 269         if (!nl)
 270                 return line + len; /* incomplete line */
 271         return nl + 1;
 272 }
 273
 274 static int generate_push_cert(struct strbuf *req_buf,
 275                               const struct ref *remote_refs,
 276                               struct send_pack_args *args,
 277                               const char *cap_string,
 278                               const char *push_cert_nonce)
 279 {
 280         const struct ref *ref;
 281         struct string_list_item *item;
 282         char *signing_key = xstrdup(get_signing_key());
 283         const char *cp, *np;
 284         struct strbuf cert = STRBUF_INIT;
 285         int update_seen = 0;
 286
 287         strbuf_addstr(&cert, "certificate version 0.1\n");
 288         strbuf_addf(&cert, "pusher %s ", signing_key);
 289         datestamp(&cert);
 290         strbuf_addch(&cert, '\n');
 291         if (args->url && *args->url) {
 292                 char *anon_url = transport_anonymize_url(args->url);
 293                 strbuf_addf(&cert, "pushee %s\n", anon_url);
 294                 free(anon_url);
 295         }
 296         if (push_cert_nonce[0])
 297                 strbuf_addf(&cert, "nonce %s\n", push_cert_nonce);
 298         if (args->push_options)
 299                 for_each_string_list_item(item, args->push_options)
 300                         strbuf_addf(&cert, "push-option %s\n", item->string);
 301         strbuf_addstr(&cert, "\n");
 302
 303         for (ref = remote_refs; ref; ref = ref->next) {
 304                 if (check_to_send_update(ref, args) < 0)
 305                         continue;
 306                 update_seen = 1;
 307                 strbuf_addf(&cert, "%s %s %s\n",
 308                             oid_to_hex(&ref->old_oid),
 309                             oid_to_hex(&ref->new_oid),
 310                             ref->name);
 311         }
 312         if (!update_seen)
 313                 goto free_return;
 314
 315         if (sign_buffer(&cert, &cert, signing_key))
 316                 die(_("failed to sign the push certificate"));
 317
 318         packet_buf_write(req_buf, "push-cert%c%s", 0, cap_string);
 319         for (cp = cert.buf; cp < cert.buf + cert.len; cp = np) {
 320                 np = next_line(cp, cert.buf + cert.len - cp);
 321                 packet_buf_write(req_buf,
 322                                  "%.*s", (int)(np - cp), cp);
 323         }
 324         packet_buf_write(req_buf, "push-cert-end\n");
 325
 326 free_return:
 327         free(signing_key);
 328         strbuf_release(&cert);
 329         return update_seen;
 330 }
 331
 332
 333 static int atomic_push_failure(struct send_pack_args *args,
 334                                struct ref *remote_refs,
 335                                struct ref *failing_ref)
 336 {
 337         struct ref *ref;
 338         /* Mark other refs as failed */
 339         for (ref = remote_refs; ref; ref = ref->next) {
 340                 if (!ref->peer_ref && !args->send_mirror)
 341                         continue;
 342
 343                 switch (ref->status) {
 344                 case REF_STATUS_EXPECTING_REPORT:
 345                         ref->status = REF_STATUS_ATOMIC_PUSH_FAILED;
 346                         continue;
 347                 default:
 348                         break; /* do nothing */
 349                 }
 350         }
 351         return error("atomic push failed for ref %s. status: %d\n",
 352                      failing_ref->name, failing_ref->status);
 353 }
 354
 355 #define NONCE_LEN_LIMIT 256
 356
 357 static void reject_invalid_nonce(const char *nonce, int len)
 358 {
 359         int i = 0;
 360
 361         if (NONCE_LEN_LIMIT <= len)
 362                 die("the receiving end asked to sign an invalid nonce <%.*s>",
 363                     len, nonce);
 364
 365         for (i = 0; i < len; i++) {
 366                 int ch = nonce[i] & 0xFF;
 367                 if (isalnum(ch) ||
 368                     ch == '-' || ch == '.' ||
 369                     ch == '/' || ch == '+' ||
 370                     ch == '=' || ch == '_')
 371                         continue;
 372                 die("the receiving end asked to sign an invalid nonce <%.*s>",
 373                     len, nonce);
 374         }
 375 }
 376
 377 int send_pack(struct send_pack_args *args,
 378               int fd[], struct child_process *conn,
 379               struct ref *remote_refs,
 380               struct oid_array *extra_have)
 381 {
 382         int in = fd[0];
 383         int out = fd[1];
 384         struct strbuf req_buf = STRBUF_INIT;
 385         struct strbuf cap_buf = STRBUF_INIT;
 386         struct ref *ref;
 387         int need_pack_data = 0;
 388         int allow_deleting_refs = 0;
 389         int status_report = 0;
 390         int use_sideband = 0;
 391         int quiet_supported = 0;
 392         int agent_supported = 0;
 393         int use_atomic = 0;
 394         int atomic_supported = 0;
 395         int use_push_options = 0;
 396         int push_options_supported = 0;
 397         unsigned cmds_sent = 0;
 398         int ret;
 399         struct async demux;
 400         const char *push_cert_nonce = NULL;
 401
 402         /* Does the other end support the reporting? */
 403         if (server_supports("report-status"))
 404                 status_report = 1;
 405         if (server_supports("delete-refs"))
 406                 allow_deleting_refs = 1;
 407         if (server_supports("ofs-delta"))
 408                 args->use_ofs_delta = 1;
 409         if (server_supports("side-band-64k"))
 410                 use_sideband = 1;
 411         if (server_supports("quiet"))
 412                 quiet_supported = 1;
 413         if (server_supports("agent"))
 414                 agent_supported = 1;
 415         if (server_supports("no-thin"))
 416                 args->use_thin_pack = 0;
 417         if (server_supports("atomic"))
 418                 atomic_supported = 1;
 419         if (server_supports("push-options"))
 420                 push_options_supported = 1;
 421
 422         if (args->push_cert != SEND_PACK_PUSH_CERT_NEVER) {
 423                 int len;
 424                 push_cert_nonce = server_feature_value("push-cert", &len);
 425                 if (push_cert_nonce) {
 426                         reject_invalid_nonce(push_cert_nonce, len);
 427                         push_cert_nonce = xmemdupz(push_cert_nonce, len);
 428                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_ALWAYS) {
 429                         die(_("the receiving end does not support --signed push"));
 430                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_IF_ASKED) {
 431                         warning(_("not sending a push certificate since the"
 432                                   " receiving end does not support --signed"
 433                                   " push"));
 434                 }
 435         }
 436
 437         if (!remote_refs) {
 438                 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
 439                         "Perhaps you should specify a branch such as 'master'.\n");
 440                 return 0;
 441         }
 442         if (args->atomic && !atomic_supported)
 443                 die(_("the receiving end does not support --atomic push"));
 444
 445         use_atomic = atomic_supported && args->atomic;
 446
 447         if (args->push_options && !push_options_supported)
 448                 die(_("the receiving end does not support push options"));
 449
 450         use_push_options = push_options_supported && args->push_options;
 451
 452         if (status_report)
 453                 strbuf_addstr(&cap_buf, " report-status");
 454         if (use_sideband)
 455                 strbuf_addstr(&cap_buf, " side-band-64k");
 456         if (quiet_supported && (args->quiet || !args->progress))
 457                 strbuf_addstr(&cap_buf, " quiet");
 458         if (use_atomic)
 459                 strbuf_addstr(&cap_buf, " atomic");
 460         if (use_push_options)
 461                 strbuf_addstr(&cap_buf, " push-options");
 462         if (agent_supported)
 463                 strbuf_addf(&cap_buf, " agent=%s", git_user_agent_sanitized());
 464
 465         /*
 466          * NEEDSWORK: why does delete-refs have to be so specific to
 467          * send-pack machinery that set_ref_status_for_push() cannot
 468          * set this bit for us???
 469          */
 470         for (ref = remote_refs; ref; ref = ref->next)
 471                 if (ref->deletion && !allow_deleting_refs)
 472                         ref->status = REF_STATUS_REJECT_NODELETE;
 473
 474         if (!args->dry_run)
 475                 advertise_shallow_grafts_buf(&req_buf);
 476
 477         if (!args->dry_run && push_cert_nonce)
 478                 cmds_sent = generate_push_cert(&req_buf, remote_refs, args,
 479                                                cap_buf.buf, push_cert_nonce);
 480
 481         /*
 482          * Clear the status for each ref and see if we need to send
 483          * the pack data.
 484          */
 485         for (ref = remote_refs; ref; ref = ref->next) {
 486                 switch (check_to_send_update(ref, args)) {
 487                 case 0: /* no error */
 488                         break;
 489                 case CHECK_REF_STATUS_REJECTED:
 490                         /*
 491                          * When we know the server would reject a ref update if
 492                          * we were to send it and we're trying to send the refs
 493                          * atomically, abort the whole operation.
 494                          */
 495                         if (use_atomic) {
 496                                 strbuf_release(&req_buf);
 497                                 strbuf_release(&cap_buf);
 498                                 return atomic_push_failure(args, remote_refs, ref);
 499                         }
 500                         /* else fallthrough */
 501                 default:
 502                         continue;
 503                 }
 504                 if (!ref->deletion)
 505                         need_pack_data = 1;
 506
 507                 if (args->dry_run || !status_report)
 508                         ref->status = REF_STATUS_OK;
 509                 else
 510                         ref->status = REF_STATUS_EXPECTING_REPORT;
 511         }
 512
 513         /*
 514          * Finally, tell the other end!
 515          */
 516         for (ref = remote_refs; ref; ref = ref->next) {
 517                 char *old_hex, *new_hex;
 518
 519                 if (args->dry_run || push_cert_nonce)
 520                         continue;
 521
 522                 if (check_to_send_update(ref, args) < 0)
 523                         continue;
 524
 525                 old_hex = oid_to_hex(&ref->old_oid);
 526                 new_hex = oid_to_hex(&ref->new_oid);
 527                 if (!cmds_sent) {
 528                         packet_buf_write(&req_buf,
 529                                          "%s %s %s%c%s",
 530                                          old_hex, new_hex, ref->name, 0,
 531                                          cap_buf.buf);
 532                         cmds_sent = 1;
 533                 } else {
 534                         packet_buf_write(&req_buf, "%s %s %s",
 535                                          old_hex, new_hex, ref->name);
 536                 }
 537         }
 538
 539         if (use_push_options) {
 540                 struct string_list_item *item;
 541
 542                 packet_buf_flush(&req_buf);
 543                 for_each_string_list_item(item, args->push_options)
 544                         packet_buf_write(&req_buf, "%s", item->string);
 545         }
 546
 547         if (args->stateless_rpc) {
 548                 if (!args->dry_run && (cmds_sent || is_repository_shallow())) {
 549                         packet_buf_flush(&req_buf);
 550                         send_sideband(out, -1, req_buf.buf, req_buf.len, LARGE_PACKET_MAX);
 551                 }
 552         } else {
 553                 write_or_die(out, req_buf.buf, req_buf.len);
 554                 packet_flush(out);
 555         }
 556         strbuf_release(&req_buf);
 557         strbuf_release(&cap_buf);
 558
 559         if (use_sideband && cmds_sent) {
 560                 memset(&demux, 0, sizeof(demux));
 561                 demux.proc = sideband_demux;
 562                 demux.data = fd;
 563                 demux.out = -1;
 564                 demux.isolate_sigpipe = 1;
 565                 if (start_async(&demux))
 566                         die("send-pack: unable to fork off sideband demultiplexer");
 567                 in = demux.out;
 568         }
 569
 570         if (need_pack_data && cmds_sent) {
 571                 if (pack_objects(out, remote_refs, extra_have, args) < 0) {
 572                         for (ref = remote_refs; ref; ref = ref->next)
 573                                 ref->status = REF_STATUS_NONE;
 574                         if (args->stateless_rpc)
 575                                 close(out);
 576                         if (git_connection_is_socket(conn))
 577                                 shutdown(fd[0], SHUT_WR);
 578
 579                         /*
 580                          * Do not even bother with the return value; we know we
 581                          * are failing, and just want the error() side effects.
 582                          */
 583                         if (status_report)
 584                                 receive_unpack_status(in);
 585
 586                         if (use_sideband) {
 587                                 close(demux.out);
 588                                 finish_async(&demux);
 589                         }
 590                         fd[1] = -1;
 591                         return -1;
 592                 }
 593                 if (!args->stateless_rpc)
 594                         /* Closed by pack_objects() via start_command() */
 595                         fd[1] = -1;
 596         }
 597         if (args->stateless_rpc && cmds_sent)
 598                 packet_flush(out);
 599
 600         if (status_report && cmds_sent)
 601                 ret = receive_status(in, remote_refs);
 602         else
 603                 ret = 0;
 604         if (args->stateless_rpc)
 605                 packet_flush(out);
 606
 607         if (use_sideband && cmds_sent) {
 608                 close(demux.out);
 609                 if (finish_async(&demux)) {
 610                         error("error in sideband demultiplexer");
 611                         ret = -1;
 612                 }
 613         }
 614
 615         if (ret < 0)
 616                 return ret;
 617
 618         if (args->porcelain)
 619                 return 0;
 620
 621         for (ref = remote_refs; ref; ref = ref->next) {
 622                 switch (ref->status) {
 623                 case REF_STATUS_NONE:
 624                 case REF_STATUS_UPTODATE:
 625                 case REF_STATUS_OK:
 626                         break;
 627                 default:
 628                         return -1;
 629                 }
 630         }
 631         return 0;
 632 }