send-pack.c

   1 #include "builtin.h"
   2 #include "commit.h"
   3 #include "refs.h"
   4 #include "pkt-line.h"
   5 #include "sideband.h"
   6 #include "run-command.h"
   7 #include "remote.h"
   8 #include "connect.h"
   9 #include "send-pack.h"
  10 #include "quote.h"
  11 #include "transport.h"
  12 #include "version.h"
  13 #include "sha1-array.h"
  14 #include "gpg-interface.h"
  15 #include "cache.h"
  16
  17 int option_parse_push_signed(const struct option *opt,
  18                              const char *arg, int unset)
  19 {
  20         if (unset) {
  21                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;
  22                 return 0;
  23         }
  24         switch (git_parse_maybe_bool(arg)) {
  25         case 1:
  26                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_ALWAYS;
  27                 return 0;
  28         case 0:
  29                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;
  30                 return 0;
  31         }
  32         if (!strcasecmp("if-asked", arg)) {
  33                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_IF_ASKED;
  34                 return 0;
  35         }
  36         die("bad %s argument: %s", opt->long_name, arg);
  37 }
  38
  39 static int feed_object(const unsigned char *sha1, int fd, int negative)
  40 {
  41         char buf[42];
  42
  43         if (negative && !has_sha1_file(sha1))
  44                 return 1;
  45
  46         memcpy(buf + negative, sha1_to_hex(sha1), 40);
  47         if (negative)
  48                 buf[0] = '^';
  49         buf[40 + negative] = '\n';
  50         return write_or_whine(fd, buf, 41 + negative, "send-pack: send refs");
  51 }
  52
  53 /*
  54  * Make a pack stream and spit it out into file descriptor fd
  55  */
  56 static int pack_objects(int fd, struct ref *refs, struct sha1_array *extra, struct send_pack_args *args)
  57 {
  58         /*
  59          * The child becomes pack-objects --revs; we feed
  60          * the revision parameters to it via its stdin and
  61          * let its stdout go back to the other end.
  62          */
  63         const char *argv[] = {
  64                 "pack-objects",
  65                 "--all-progress-implied",
  66                 "--revs",
  67                 "--stdout",
  68                 NULL,
  69                 NULL,
  70                 NULL,
  71                 NULL,
  72                 NULL,
  73                 NULL,
  74         };
  75         struct child_process po = CHILD_PROCESS_INIT;
  76         int i;
  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         for (i = 0; i < extra->nr; i++)
 101                 if (!feed_object(extra->sha1[i], po.in, 1))
 102                         break;
 103
 104         while (refs) {
 105                 if (!is_null_sha1(refs->old_sha1) &&
 106                     !feed_object(refs->old_sha1, po.in, 1))
 107                         break;
 108                 if (!is_null_sha1(refs->new_sha1) &&
 109                     !feed_object(refs->new_sha1, po.in, 0))
 110                         break;
 111                 refs = refs->next;
 112         }
 113
 114         close(po.in);
 115
 116         if (args->stateless_rpc) {
 117                 char *buf = xmalloc(LARGE_PACKET_MAX);
 118                 while (1) {
 119                         ssize_t n = xread(po.out, buf, LARGE_PACKET_MAX);
 120                         if (n <= 0)
 121                                 break;
 122                         send_sideband(fd, -1, buf, n, LARGE_PACKET_MAX);
 123                 }
 124                 free(buf);
 125                 close(po.out);
 126                 po.out = -1;
 127         }
 128
 129         if (finish_command(&po))
 130                 return -1;
 131         return 0;
 132 }
 133
 134 static int receive_status(int in, struct ref *refs)
 135 {
 136         struct ref *hint;
 137         int ret = 0;
 138         char *line = packet_read_line(in, NULL);
 139         if (!starts_with(line, "unpack "))
 140                 return error("did not receive remote status");
 141         if (strcmp(line, "unpack ok")) {
 142                 error("unpack failed: %s", line + 7);
 143                 ret = -1;
 144         }
 145         hint = NULL;
 146         while (1) {
 147                 char *refname;
 148                 char *msg;
 149                 line = packet_read_line(in, NULL);
 150                 if (!line)
 151                         break;
 152                 if (!starts_with(line, "ok ") && !starts_with(line, "ng ")) {
 153                         error("invalid ref status from remote: %s", line);
 154                         ret = -1;
 155                         break;
 156                 }
 157
 158                 refname = line + 3;
 159                 msg = strchr(refname, ' ');
 160                 if (msg)
 161                         *msg++ = '\0';
 162
 163                 /* first try searching at our hint, falling back to all refs */
 164                 if (hint)
 165                         hint = find_ref_by_name(hint, refname);
 166                 if (!hint)
 167                         hint = find_ref_by_name(refs, refname);
 168                 if (!hint) {
 169                         warning("remote reported status on unknown ref: %s",
 170                                         refname);
 171                         continue;
 172                 }
 173                 if (hint->status != REF_STATUS_EXPECTING_REPORT) {
 174                         warning("remote reported status on unexpected ref: %s",
 175                                         refname);
 176                         continue;
 177                 }
 178
 179                 if (line[0] == 'o' && line[1] == 'k')
 180                         hint->status = REF_STATUS_OK;
 181                 else {
 182                         hint->status = REF_STATUS_REMOTE_REJECT;
 183                         ret = -1;
 184                 }
 185                 if (msg)
 186                         hint->remote_status = xstrdup(msg);
 187                 /* start our next search from the next ref */
 188                 hint = hint->next;
 189         }
 190         return ret;
 191 }
 192
 193 static int sideband_demux(int in, int out, void *data)
 194 {
 195         int *fd = data, ret;
 196 #ifdef NO_PTHREADS
 197         close(fd[1]);
 198 #endif
 199         ret = recv_sideband("send-pack", fd[0], out);
 200         close(out);
 201         return ret;
 202 }
 203
 204 static int advertise_shallow_grafts_cb(const struct commit_graft *graft, void *cb)
 205 {
 206         struct strbuf *sb = cb;
 207         if (graft->nr_parent == -1)
 208                 packet_buf_write(sb, "shallow %s\n", oid_to_hex(&graft->oid));
 209         return 0;
 210 }
 211
 212 static void advertise_shallow_grafts_buf(struct strbuf *sb)
 213 {
 214         if (!is_repository_shallow())
 215                 return;
 216         for_each_commit_graft(advertise_shallow_grafts_cb, sb);
 217 }
 218
 219 #define CHECK_REF_NO_PUSH -1
 220 #define CHECK_REF_STATUS_REJECTED -2
 221 #define CHECK_REF_UPTODATE -3
 222 static int check_to_send_update(const struct ref *ref, const struct send_pack_args *args)
 223 {
 224         if (!ref->peer_ref && !args->send_mirror)
 225                 return CHECK_REF_NO_PUSH;
 226
 227         /* Check for statuses set by set_ref_status_for_push() */
 228         switch (ref->status) {
 229         case REF_STATUS_REJECT_NONFASTFORWARD:
 230         case REF_STATUS_REJECT_ALREADY_EXISTS:
 231         case REF_STATUS_REJECT_FETCH_FIRST:
 232         case REF_STATUS_REJECT_NEEDS_FORCE:
 233         case REF_STATUS_REJECT_STALE:
 234         case REF_STATUS_REJECT_NODELETE:
 235                 return CHECK_REF_STATUS_REJECTED;
 236         case REF_STATUS_UPTODATE:
 237                 return CHECK_REF_UPTODATE;
 238         default:
 239                 return 0;
 240         }
 241 }
 242
 243 /*
 244  * the beginning of the next line, or the end of buffer.
 245  *
 246  * NEEDSWORK: perhaps move this to git-compat-util.h or somewhere and
 247  * convert many similar uses found by "git grep -A4 memchr".
 248  */
 249 static const char *next_line(const char *line, size_t len)
 250 {
 251         const char *nl = memchr(line, '\n', len);
 252         if (!nl)
 253                 return line + len; /* incomplete line */
 254         return nl + 1;
 255 }
 256
 257 static int generate_push_cert(struct strbuf *req_buf,
 258                               const struct ref *remote_refs,
 259                               struct send_pack_args *args,
 260                               const char *cap_string,
 261                               const char *push_cert_nonce)
 262 {
 263         const struct ref *ref;
 264         char *signing_key = xstrdup(get_signing_key());
 265         const char *cp, *np;
 266         struct strbuf cert = STRBUF_INIT;
 267         int update_seen = 0;
 268
 269         strbuf_addf(&cert, "certificate version 0.1\n");
 270         strbuf_addf(&cert, "pusher %s ", signing_key);
 271         datestamp(&cert);
 272         strbuf_addch(&cert, '\n');
 273         if (args->url && *args->url) {
 274                 char *anon_url = transport_anonymize_url(args->url);
 275                 strbuf_addf(&cert, "pushee %s\n", anon_url);
 276                 free(anon_url);
 277         }
 278         if (push_cert_nonce[0])
 279                 strbuf_addf(&cert, "nonce %s\n", push_cert_nonce);
 280         strbuf_addstr(&cert, "\n");
 281
 282         for (ref = remote_refs; ref; ref = ref->next) {
 283                 if (check_to_send_update(ref, args) < 0)
 284                         continue;
 285                 update_seen = 1;
 286                 strbuf_addf(&cert, "%s %s %s\n",
 287                             sha1_to_hex(ref->old_sha1),
 288                             sha1_to_hex(ref->new_sha1),
 289                             ref->name);
 290         }
 291         if (!update_seen)
 292                 goto free_return;
 293
 294         if (sign_buffer(&cert, &cert, signing_key))
 295                 die(_("failed to sign the push certificate"));
 296
 297         packet_buf_write(req_buf, "push-cert%c%s", 0, cap_string);
 298         for (cp = cert.buf; cp < cert.buf + cert.len; cp = np) {
 299                 np = next_line(cp, cert.buf + cert.len - cp);
 300                 packet_buf_write(req_buf,
 301                                  "%.*s", (int)(np - cp), cp);
 302         }
 303         packet_buf_write(req_buf, "push-cert-end\n");
 304
 305 free_return:
 306         free(signing_key);
 307         strbuf_release(&cert);
 308         return update_seen;
 309 }
 310
 311
 312 static int atomic_push_failure(struct send_pack_args *args,
 313                                struct ref *remote_refs,
 314                                struct ref *failing_ref)
 315 {
 316         struct ref *ref;
 317         /* Mark other refs as failed */
 318         for (ref = remote_refs; ref; ref = ref->next) {
 319                 if (!ref->peer_ref && !args->send_mirror)
 320                         continue;
 321
 322                 switch (ref->status) {
 323                 case REF_STATUS_EXPECTING_REPORT:
 324                         ref->status = REF_STATUS_ATOMIC_PUSH_FAILED;
 325                         continue;
 326                 default:
 327                         break; /* do nothing */
 328                 }
 329         }
 330         return error("atomic push failed for ref %s. status: %d\n",
 331                      failing_ref->name, failing_ref->status);
 332 }
 333
 334 #define NONCE_LEN_LIMIT 256
 335
 336 static void reject_invalid_nonce(const char *nonce, int len)
 337 {
 338         int i = 0;
 339
 340         if (NONCE_LEN_LIMIT <= len)
 341                 die("the receiving end asked to sign an invalid nonce <%.*s>",
 342                     len, nonce);
 343
 344         for (i = 0; i < len; i++) {
 345                 int ch = nonce[i] & 0xFF;
 346                 if (isalnum(ch) ||
 347                     ch == '-' || ch == '.' ||
 348                     ch == '/' || ch == '+' ||
 349                     ch == '=' || ch == '_')
 350                         continue;
 351                 die("the receiving end asked to sign an invalid nonce <%.*s>",
 352                     len, nonce);
 353         }
 354 }
 355
 356 int send_pack(struct send_pack_args *args,
 357               int fd[], struct child_process *conn,
 358               struct ref *remote_refs,
 359               struct sha1_array *extra_have)
 360 {
 361         int in = fd[0];
 362         int out = fd[1];
 363         struct strbuf req_buf = STRBUF_INIT;
 364         struct strbuf cap_buf = STRBUF_INIT;
 365         struct ref *ref;
 366         int need_pack_data = 0;
 367         int allow_deleting_refs = 0;
 368         int status_report = 0;
 369         int use_sideband = 0;
 370         int quiet_supported = 0;
 371         int agent_supported = 0;
 372         int use_atomic = 0;
 373         int atomic_supported = 0;
 374         unsigned cmds_sent = 0;
 375         int ret;
 376         struct async demux;
 377         const char *push_cert_nonce = NULL;
 378
 379         /* Does the other end support the reporting? */
 380         if (server_supports("report-status"))
 381                 status_report = 1;
 382         if (server_supports("delete-refs"))
 383                 allow_deleting_refs = 1;
 384         if (server_supports("ofs-delta"))
 385                 args->use_ofs_delta = 1;
 386         if (server_supports("side-band-64k"))
 387                 use_sideband = 1;
 388         if (server_supports("quiet"))
 389                 quiet_supported = 1;
 390         if (server_supports("agent"))
 391                 agent_supported = 1;
 392         if (server_supports("no-thin"))
 393                 args->use_thin_pack = 0;
 394         if (server_supports("atomic"))
 395                 atomic_supported = 1;
 396
 397         if (args->push_cert != SEND_PACK_PUSH_CERT_NEVER) {
 398                 int len;
 399                 push_cert_nonce = server_feature_value("push-cert", &len);
 400                 if (push_cert_nonce) {
 401                         reject_invalid_nonce(push_cert_nonce, len);
 402                         push_cert_nonce = xmemdupz(push_cert_nonce, len);
 403                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_ALWAYS) {
 404                         die(_("the receiving end does not support --signed push"));
 405                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_IF_ASKED) {
 406                         warning(_("not sending a push certificate since the"
 407                                   " receiving end does not support --signed"
 408                                   " push"));
 409                 }
 410         }
 411
 412         if (!remote_refs) {
 413                 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
 414                         "Perhaps you should specify a branch such as 'master'.\n");
 415                 return 0;
 416         }
 417         if (args->atomic && !atomic_supported)
 418                 die(_("the receiving end does not support --atomic push"));
 419
 420         use_atomic = atomic_supported && args->atomic;
 421
 422         if (status_report)
 423                 strbuf_addstr(&cap_buf, " report-status");
 424         if (use_sideband)
 425                 strbuf_addstr(&cap_buf, " side-band-64k");
 426         if (quiet_supported && (args->quiet || !args->progress))
 427                 strbuf_addstr(&cap_buf, " quiet");
 428         if (use_atomic)
 429                 strbuf_addstr(&cap_buf, " atomic");
 430         if (agent_supported)
 431                 strbuf_addf(&cap_buf, " agent=%s", git_user_agent_sanitized());
 432
 433         /*
 434          * NEEDSWORK: why does delete-refs have to be so specific to
 435          * send-pack machinery that set_ref_status_for_push() cannot
 436          * set this bit for us???
 437          */
 438         for (ref = remote_refs; ref; ref = ref->next)
 439                 if (ref->deletion && !allow_deleting_refs)
 440                         ref->status = REF_STATUS_REJECT_NODELETE;
 441
 442         if (!args->dry_run)
 443                 advertise_shallow_grafts_buf(&req_buf);
 444
 445         if (!args->dry_run && push_cert_nonce)
 446                 cmds_sent = generate_push_cert(&req_buf, remote_refs, args,
 447                                                cap_buf.buf, push_cert_nonce);
 448
 449         /*
 450          * Clear the status for each ref and see if we need to send
 451          * the pack data.
 452          */
 453         for (ref = remote_refs; ref; ref = ref->next) {
 454                 switch (check_to_send_update(ref, args)) {
 455                 case 0: /* no error */
 456                         break;
 457                 case CHECK_REF_STATUS_REJECTED:
 458                         /*
 459                          * When we know the server would reject a ref update if
 460                          * we were to send it and we're trying to send the refs
 461                          * atomically, abort the whole operation.
 462                          */
 463                         if (use_atomic)
 464                                 return atomic_push_failure(args, remote_refs, ref);
 465                         /* Fallthrough for non atomic case. */
 466                 default:
 467                         continue;
 468                 }
 469                 if (!ref->deletion)
 470                         need_pack_data = 1;
 471
 472                 if (args->dry_run || !status_report)
 473                         ref->status = REF_STATUS_OK;
 474                 else
 475                         ref->status = REF_STATUS_EXPECTING_REPORT;
 476         }
 477
 478         /*
 479          * Finally, tell the other end!
 480          */
 481         for (ref = remote_refs; ref; ref = ref->next) {
 482                 char *old_hex, *new_hex;
 483
 484                 if (args->dry_run || push_cert_nonce)
 485                         continue;
 486
 487                 if (check_to_send_update(ref, args) < 0)
 488                         continue;
 489
 490                 old_hex = sha1_to_hex(ref->old_sha1);
 491                 new_hex = sha1_to_hex(ref->new_sha1);
 492                 if (!cmds_sent) {
 493                         packet_buf_write(&req_buf,
 494                                          "%s %s %s%c%s",
 495                                          old_hex, new_hex, ref->name, 0,
 496                                          cap_buf.buf);
 497                         cmds_sent = 1;
 498                 } else {
 499                         packet_buf_write(&req_buf, "%s %s %s",
 500                                          old_hex, new_hex, ref->name);
 501                 }
 502         }
 503
 504         if (args->stateless_rpc) {
 505                 if (!args->dry_run && (cmds_sent || is_repository_shallow())) {
 506                         packet_buf_flush(&req_buf);
 507                         send_sideband(out, -1, req_buf.buf, req_buf.len, LARGE_PACKET_MAX);
 508                 }
 509         } else {
 510                 write_or_die(out, req_buf.buf, req_buf.len);
 511                 packet_flush(out);
 512         }
 513         strbuf_release(&req_buf);
 514         strbuf_release(&cap_buf);
 515
 516         if (use_sideband && cmds_sent) {
 517                 memset(&demux, 0, sizeof(demux));
 518                 demux.proc = sideband_demux;
 519                 demux.data = fd;
 520                 demux.out = -1;
 521                 if (start_async(&demux))
 522                         die("send-pack: unable to fork off sideband demultiplexer");
 523                 in = demux.out;
 524         }
 525
 526         if (need_pack_data && cmds_sent) {
 527                 if (pack_objects(out, remote_refs, extra_have, args) < 0) {
 528                         for (ref = remote_refs; ref; ref = ref->next)
 529                                 ref->status = REF_STATUS_NONE;
 530                         if (args->stateless_rpc)
 531                                 close(out);
 532                         if (git_connection_is_socket(conn))
 533                                 shutdown(fd[0], SHUT_WR);
 534                         if (use_sideband)
 535                                 finish_async(&demux);
 536                         fd[1] = -1;
 537                         return -1;
 538                 }
 539                 if (!args->stateless_rpc)
 540                         /* Closed by pack_objects() via start_command() */
 541                         fd[1] = -1;
 542         }
 543         if (args->stateless_rpc && cmds_sent)
 544                 packet_flush(out);
 545
 546         if (status_report && cmds_sent)
 547                 ret = receive_status(in, remote_refs);
 548         else
 549                 ret = 0;
 550         if (args->stateless_rpc)
 551                 packet_flush(out);
 552
 553         if (use_sideband && cmds_sent) {
 554                 if (finish_async(&demux)) {
 555                         error("error in sideband demultiplexer");
 556                         ret = -1;
 557                 }
 558                 close(demux.out);
 559         }
 560
 561         if (ret < 0)
 562                 return ret;
 563
 564         if (args->porcelain)
 565                 return 0;
 566
 567         for (ref = remote_refs; ref; ref = ref->next) {
 568                 switch (ref->status) {
 569                 case REF_STATUS_NONE:
 570                 case REF_STATUS_UPTODATE:
 571                 case REF_STATUS_OK:
 572                         break;
 573                 default:
 574                         return -1;
 575                 }
 576         }
 577         return 0;
 578 }