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