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
  16 static int feed_object(const unsigned char *sha1, int fd, int negative)
  17 {
  18         char buf[42];
  19
  20         if (negative && !has_sha1_file(sha1))
  21                 return 1;
  22
  23         memcpy(buf + negative, sha1_to_hex(sha1), 40);
  24         if (negative)
  25                 buf[0] = '^';
  26         buf[40 + negative] = '\n';
  27         return write_or_whine(fd, buf, 41 + negative, "send-pack: send refs");
  28 }
  29
  30 /*
  31  * Make a pack stream and spit it out into file descriptor fd
  32  */
  33 static int pack_objects(int fd, struct ref *refs, struct sha1_array *extra, struct send_pack_args *args)
  34 {
  35         /*
  36          * The child becomes pack-objects --revs; we feed
  37          * the revision parameters to it via its stdin and
  38          * let its stdout go back to the other end.
  39          */
  40         const char *argv[] = {
  41                 "pack-objects",
  42                 "--all-progress-implied",
  43                 "--revs",
  44                 "--stdout",
  45                 NULL,
  46                 NULL,
  47                 NULL,
  48                 NULL,
  49                 NULL,
  50                 NULL,
  51         };
  52         struct child_process po = CHILD_PROCESS_INIT;
  53         int i;
  54
  55         i = 4;
  56         if (args->use_thin_pack)
  57                 argv[i++] = "--thin";
  58         if (args->use_ofs_delta)
  59                 argv[i++] = "--delta-base-offset";
  60         if (args->quiet || !args->progress)
  61                 argv[i++] = "-q";
  62         if (args->progress)
  63                 argv[i++] = "--progress";
  64         if (is_repository_shallow())
  65                 argv[i++] = "--shallow";
  66         po.argv = argv;
  67         po.in = -1;
  68         po.out = args->stateless_rpc ? -1 : fd;
  69         po.git_cmd = 1;
  70         if (start_command(&po))
  71                 die_errno("git pack-objects failed");
  72
  73         /*
  74          * We feed the pack-objects we just spawned with revision
  75          * parameters by writing to the pipe.
  76          */
  77         for (i = 0; i < extra->nr; i++)
  78                 if (!feed_object(extra->sha1[i], po.in, 1))
  79                         break;
  80
  81         while (refs) {
  82                 if (!is_null_sha1(refs->old_sha1) &&
  83                     !feed_object(refs->old_sha1, po.in, 1))
  84                         break;
  85                 if (!is_null_sha1(refs->new_sha1) &&
  86                     !feed_object(refs->new_sha1, po.in, 0))
  87                         break;
  88                 refs = refs->next;
  89         }
  90
  91         close(po.in);
  92
  93         if (args->stateless_rpc) {
  94                 char *buf = xmalloc(LARGE_PACKET_MAX);
  95                 while (1) {
  96                         ssize_t n = xread(po.out, buf, LARGE_PACKET_MAX);
  97                         if (n <= 0)
  98                                 break;
  99                         send_sideband(fd, -1, buf, n, LARGE_PACKET_MAX);
 100                 }
 101                 free(buf);
 102                 close(po.out);
 103                 po.out = -1;
 104         }
 105
 106         if (finish_command(&po))
 107                 return -1;
 108         return 0;
 109 }
 110
 111 static int receive_status(int in, struct ref *refs)
 112 {
 113         struct ref *hint;
 114         int ret = 0;
 115         char *line = packet_read_line(in, NULL);
 116         if (!starts_with(line, "unpack "))
 117                 return error("did not receive remote status");
 118         if (strcmp(line, "unpack ok")) {
 119                 error("unpack failed: %s", line + 7);
 120                 ret = -1;
 121         }
 122         hint = NULL;
 123         while (1) {
 124                 char *refname;
 125                 char *msg;
 126                 line = packet_read_line(in, NULL);
 127                 if (!line)
 128                         break;
 129                 if (!starts_with(line, "ok ") && !starts_with(line, "ng ")) {
 130                         error("invalid ref status from remote: %s", line);
 131                         ret = -1;
 132                         break;
 133                 }
 134
 135                 refname = line + 3;
 136                 msg = strchr(refname, ' ');
 137                 if (msg)
 138                         *msg++ = '\0';
 139
 140                 /* first try searching at our hint, falling back to all refs */
 141                 if (hint)
 142                         hint = find_ref_by_name(hint, refname);
 143                 if (!hint)
 144                         hint = find_ref_by_name(refs, refname);
 145                 if (!hint) {
 146                         warning("remote reported status on unknown ref: %s",
 147                                         refname);
 148                         continue;
 149                 }
 150                 if (hint->status != REF_STATUS_EXPECTING_REPORT) {
 151                         warning("remote reported status on unexpected ref: %s",
 152                                         refname);
 153                         continue;
 154                 }
 155
 156                 if (line[0] == 'o' && line[1] == 'k')
 157                         hint->status = REF_STATUS_OK;
 158                 else {
 159                         hint->status = REF_STATUS_REMOTE_REJECT;
 160                         ret = -1;
 161                 }
 162                 if (msg)
 163                         hint->remote_status = xstrdup(msg);
 164                 /* start our next search from the next ref */
 165                 hint = hint->next;
 166         }
 167         return ret;
 168 }
 169
 170 static int sideband_demux(int in, int out, void *data)
 171 {
 172         int *fd = data, ret;
 173 #ifdef NO_PTHREADS
 174         close(fd[1]);
 175 #endif
 176         ret = recv_sideband("send-pack", fd[0], out);
 177         close(out);
 178         return ret;
 179 }
 180
 181 static int advertise_shallow_grafts_cb(const struct commit_graft *graft, void *cb)
 182 {
 183         struct strbuf *sb = cb;
 184         if (graft->nr_parent == -1)
 185                 packet_buf_write(sb, "shallow %s\n", sha1_to_hex(graft->sha1));
 186         return 0;
 187 }
 188
 189 static void advertise_shallow_grafts_buf(struct strbuf *sb)
 190 {
 191         if (!is_repository_shallow())
 192                 return;
 193         for_each_commit_graft(advertise_shallow_grafts_cb, sb);
 194 }
 195
 196 #define CHECK_REF_NO_PUSH -1
 197 #define CHECK_REF_STATUS_REJECTED -2
 198 #define CHECK_REF_UPTODATE -3
 199 static int check_to_send_update(const struct ref *ref, const struct send_pack_args *args)
 200 {
 201         if (!ref->peer_ref && !args->send_mirror)
 202                 return CHECK_REF_NO_PUSH;
 203
 204         /* Check for statuses set by set_ref_status_for_push() */
 205         switch (ref->status) {
 206         case REF_STATUS_REJECT_NONFASTFORWARD:
 207         case REF_STATUS_REJECT_ALREADY_EXISTS:
 208         case REF_STATUS_REJECT_FETCH_FIRST:
 209         case REF_STATUS_REJECT_NEEDS_FORCE:
 210         case REF_STATUS_REJECT_STALE:
 211         case REF_STATUS_REJECT_NODELETE:
 212                 return CHECK_REF_STATUS_REJECTED;
 213         case REF_STATUS_UPTODATE:
 214                 return CHECK_REF_UPTODATE;
 215         default:
 216                 return 0;
 217         }
 218 }
 219
 220 /*
 221  * the beginning of the next line, or the end of buffer.
 222  *
 223  * NEEDSWORK: perhaps move this to git-compat-util.h or somewhere and
 224  * convert many similar uses found by "git grep -A4 memchr".
 225  */
 226 static const char *next_line(const char *line, size_t len)
 227 {
 228         const char *nl = memchr(line, '\n', len);
 229         if (!nl)
 230                 return line + len; /* incomplete line */
 231         return nl + 1;
 232 }
 233
 234 static int generate_push_cert(struct strbuf *req_buf,
 235                               const struct ref *remote_refs,
 236                               struct send_pack_args *args,
 237                               const char *cap_string,
 238                               const char *push_cert_nonce)
 239 {
 240         const struct ref *ref;
 241         char *signing_key = xstrdup(get_signing_key());
 242         const char *cp, *np;
 243         struct strbuf cert = STRBUF_INIT;
 244         int update_seen = 0;
 245
 246         strbuf_addf(&cert, "certificate version 0.1\n");
 247         strbuf_addf(&cert, "pusher %s ", signing_key);
 248         datestamp(&cert);
 249         strbuf_addch(&cert, '\n');
 250         if (args->url && *args->url) {
 251                 char *anon_url = transport_anonymize_url(args->url);
 252                 strbuf_addf(&cert, "pushee %s\n", anon_url);
 253                 free(anon_url);
 254         }
 255         if (push_cert_nonce[0])
 256                 strbuf_addf(&cert, "nonce %s\n", push_cert_nonce);
 257         strbuf_addstr(&cert, "\n");
 258
 259         for (ref = remote_refs; ref; ref = ref->next) {
 260                 if (check_to_send_update(ref, args) < 0)
 261                         continue;
 262                 update_seen = 1;
 263                 strbuf_addf(&cert, "%s %s %s\n",
 264                             sha1_to_hex(ref->old_sha1),
 265                             sha1_to_hex(ref->new_sha1),
 266                             ref->name);
 267         }
 268         if (!update_seen)
 269                 goto free_return;
 270
 271         if (sign_buffer(&cert, &cert, signing_key))
 272                 die(_("failed to sign the push certificate"));
 273
 274         packet_buf_write(req_buf, "push-cert%c%s", 0, cap_string);
 275         for (cp = cert.buf; cp < cert.buf + cert.len; cp = np) {
 276                 np = next_line(cp, cert.buf + cert.len - cp);
 277                 packet_buf_write(req_buf,
 278                                  "%.*s", (int)(np - cp), cp);
 279         }
 280         packet_buf_write(req_buf, "push-cert-end\n");
 281
 282 free_return:
 283         free(signing_key);
 284         strbuf_release(&cert);
 285         return update_seen;
 286 }
 287
 288
 289 static int atomic_push_failure(struct send_pack_args *args,
 290                                struct ref *remote_refs,
 291                                struct ref *failing_ref)
 292 {
 293         struct ref *ref;
 294         /* Mark other refs as failed */
 295         for (ref = remote_refs; ref; ref = ref->next) {
 296                 if (!ref->peer_ref && !args->send_mirror)
 297                         continue;
 298
 299                 switch (ref->status) {
 300                 case REF_STATUS_EXPECTING_REPORT:
 301                         ref->status = REF_STATUS_ATOMIC_PUSH_FAILED;
 302                         continue;
 303                 default:
 304                         break; /* do nothing */
 305                 }
 306         }
 307         return error("atomic push failed for ref %s. status: %d\n",
 308                      failing_ref->name, failing_ref->status);
 309 }
 310
 311 #define NONCE_LEN_LIMIT 256
 312
 313 static void reject_invalid_nonce(const char *nonce, int len)
 314 {
 315         int i = 0;
 316
 317         if (NONCE_LEN_LIMIT <= len)
 318                 die("the receiving end asked to sign an invalid nonce <%.*s>",
 319                     len, nonce);
 320
 321         for (i = 0; i < len; i++) {
 322                 int ch = nonce[i] & 0xFF;
 323                 if (isalnum(ch) ||
 324                     ch == '-' || ch == '.' ||
 325                     ch == '/' || ch == '+' ||
 326                     ch == '=' || ch == '_')
 327                         continue;
 328                 die("the receiving end asked to sign an invalid nonce <%.*s>",
 329                     len, nonce);
 330         }
 331 }
 332
 333 int send_pack(struct send_pack_args *args,
 334               int fd[], struct child_process *conn,
 335               struct ref *remote_refs,
 336               struct sha1_array *extra_have)
 337 {
 338         int in = fd[0];
 339         int out = fd[1];
 340         struct strbuf req_buf = STRBUF_INIT;
 341         struct strbuf cap_buf = STRBUF_INIT;
 342         struct ref *ref;
 343         int need_pack_data = 0;
 344         int allow_deleting_refs = 0;
 345         int status_report = 0;
 346         int use_sideband = 0;
 347         int quiet_supported = 0;
 348         int agent_supported = 0;
 349         int use_atomic = 0;
 350         int atomic_supported = 0;
 351         unsigned cmds_sent = 0;
 352         int ret;
 353         struct async demux;
 354         const char *push_cert_nonce = NULL;
 355
 356         /* Does the other end support the reporting? */
 357         if (server_supports("report-status"))
 358                 status_report = 1;
 359         if (server_supports("delete-refs"))
 360                 allow_deleting_refs = 1;
 361         if (server_supports("ofs-delta"))
 362                 args->use_ofs_delta = 1;
 363         if (server_supports("side-band-64k"))
 364                 use_sideband = 1;
 365         if (server_supports("quiet"))
 366                 quiet_supported = 1;
 367         if (server_supports("agent"))
 368                 agent_supported = 1;
 369         if (server_supports("no-thin"))
 370                 args->use_thin_pack = 0;
 371         if (server_supports("atomic"))
 372                 atomic_supported = 1;
 373         if (args->push_cert) {
 374                 int len;
 375
 376                 push_cert_nonce = server_feature_value("push-cert", &len);
 377                 if (!push_cert_nonce)
 378                         die(_("the receiving end does not support --signed push"));
 379                 reject_invalid_nonce(push_cert_nonce, len);
 380                 push_cert_nonce = xmemdupz(push_cert_nonce, len);
 381         }
 382
 383         if (!remote_refs) {
 384                 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
 385                         "Perhaps you should specify a branch such as 'master'.\n");
 386                 return 0;
 387         }
 388         if (args->atomic && !atomic_supported)
 389                 die(_("the receiving end does not support --atomic push"));
 390
 391         use_atomic = atomic_supported && args->atomic;
 392
 393         if (status_report)
 394                 strbuf_addstr(&cap_buf, " report-status");
 395         if (use_sideband)
 396                 strbuf_addstr(&cap_buf, " side-band-64k");
 397         if (quiet_supported && (args->quiet || !args->progress))
 398                 strbuf_addstr(&cap_buf, " quiet");
 399         if (use_atomic)
 400                 strbuf_addstr(&cap_buf, " atomic");
 401         if (agent_supported)
 402                 strbuf_addf(&cap_buf, " agent=%s", git_user_agent_sanitized());
 403
 404         /*
 405          * NEEDSWORK: why does delete-refs have to be so specific to
 406          * send-pack machinery that set_ref_status_for_push() cannot
 407          * set this bit for us???
 408          */
 409         for (ref = remote_refs; ref; ref = ref->next)
 410                 if (ref->deletion && !allow_deleting_refs)
 411                         ref->status = REF_STATUS_REJECT_NODELETE;
 412
 413         if (!args->dry_run)
 414                 advertise_shallow_grafts_buf(&req_buf);
 415
 416         if (!args->dry_run && args->push_cert)
 417                 cmds_sent = generate_push_cert(&req_buf, remote_refs, args,
 418                                                cap_buf.buf, push_cert_nonce);
 419
 420         /*
 421          * Clear the status for each ref and see if we need to send
 422          * the pack data.
 423          */
 424         for (ref = remote_refs; ref; ref = ref->next) {
 425                 switch (check_to_send_update(ref, args)) {
 426                 case 0: /* no error */
 427                         break;
 428                 case CHECK_REF_STATUS_REJECTED:
 429                         /*
 430                          * When we know the server would reject a ref update if
 431                          * we were to send it and we're trying to send the refs
 432                          * atomically, abort the whole operation.
 433                          */
 434                         if (use_atomic)
 435                                 return atomic_push_failure(args, remote_refs, ref);
 436                         /* Fallthrough for non atomic case. */
 437                 default:
 438                         continue;
 439                 }
 440                 if (!ref->deletion)
 441                         need_pack_data = 1;
 442
 443                 if (args->dry_run || !status_report)
 444                         ref->status = REF_STATUS_OK;
 445                 else
 446                         ref->status = REF_STATUS_EXPECTING_REPORT;
 447         }
 448
 449         /*
 450          * Finally, tell the other end!
 451          */
 452         for (ref = remote_refs; ref; ref = ref->next) {
 453                 char *old_hex, *new_hex;
 454
 455                 if (args->dry_run || args->push_cert)
 456                         continue;
 457
 458                 if (check_to_send_update(ref, args) < 0)
 459                         continue;
 460
 461                 old_hex = sha1_to_hex(ref->old_sha1);
 462                 new_hex = sha1_to_hex(ref->new_sha1);
 463                 if (!cmds_sent) {
 464                         packet_buf_write(&req_buf,
 465                                          "%s %s %s%c%s",
 466                                          old_hex, new_hex, ref->name, 0,
 467                                          cap_buf.buf);
 468                         cmds_sent = 1;
 469                 } else {
 470                         packet_buf_write(&req_buf, "%s %s %s",
 471                                          old_hex, new_hex, ref->name);
 472                 }
 473         }
 474
 475         if (args->stateless_rpc) {
 476                 if (!args->dry_run && (cmds_sent || is_repository_shallow())) {
 477                         packet_buf_flush(&req_buf);
 478                         send_sideband(out, -1, req_buf.buf, req_buf.len, LARGE_PACKET_MAX);
 479                 }
 480         } else {
 481                 write_or_die(out, req_buf.buf, req_buf.len);
 482                 packet_flush(out);
 483         }
 484         strbuf_release(&req_buf);
 485         strbuf_release(&cap_buf);
 486
 487         if (use_sideband && cmds_sent) {
 488                 memset(&demux, 0, sizeof(demux));
 489                 demux.proc = sideband_demux;
 490                 demux.data = fd;
 491                 demux.out = -1;
 492                 if (start_async(&demux))
 493                         die("send-pack: unable to fork off sideband demultiplexer");
 494                 in = demux.out;
 495         }
 496
 497         if (need_pack_data && cmds_sent) {
 498                 if (pack_objects(out, remote_refs, extra_have, args) < 0) {
 499                         for (ref = remote_refs; ref; ref = ref->next)
 500                                 ref->status = REF_STATUS_NONE;
 501                         if (args->stateless_rpc)
 502                                 close(out);
 503                         if (git_connection_is_socket(conn))
 504                                 shutdown(fd[0], SHUT_WR);
 505                         if (use_sideband)
 506                                 finish_async(&demux);
 507                         fd[1] = -1;
 508                         return -1;
 509                 }
 510                 if (!args->stateless_rpc)
 511                         /* Closed by pack_objects() via start_command() */
 512                         fd[1] = -1;
 513         }
 514         if (args->stateless_rpc && cmds_sent)
 515                 packet_flush(out);
 516
 517         if (status_report && cmds_sent)
 518                 ret = receive_status(in, remote_refs);
 519         else
 520                 ret = 0;
 521         if (args->stateless_rpc)
 522                 packet_flush(out);
 523
 524         if (use_sideband && cmds_sent) {
 525                 if (finish_async(&demux)) {
 526                         error("error in sideband demultiplexer");
 527                         ret = -1;
 528                 }
 529                 close(demux.out);
 530         }
 531
 532         if (ret < 0)
 533                 return ret;
 534
 535         if (args->porcelain)
 536                 return 0;
 537
 538         for (ref = remote_refs; ref; ref = ref->next) {
 539                 switch (ref->status) {
 540                 case REF_STATUS_NONE:
 541                 case REF_STATUS_UPTODATE:
 542                 case REF_STATUS_OK:
 543                         break;
 544                 default:
 545                         return -1;
 546                 }
 547         }
 548         return 0;
 549 }