merge: move doc to ll-merge.h
[git] / send-pack.c
1 #include "builtin.h"
2 #include "config.h"
3 #include "commit.h"
4 #include "refs.h"
5 #include "object-store.h"
6 #include "pkt-line.h"
7 #include "sideband.h"
8 #include "run-command.h"
9 #include "remote.h"
10 #include "connect.h"
11 #include "send-pack.h"
12 #include "quote.h"
13 #include "transport.h"
14 #include "version.h"
15 #include "sha1-array.h"
16 #include "gpg-interface.h"
17 #include "cache.h"
18
19 int option_parse_push_signed(const struct option *opt,
20                              const char *arg, int unset)
21 {
22         if (unset) {
23                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;
24                 return 0;
25         }
26         switch (git_parse_maybe_bool(arg)) {
27         case 1:
28                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_ALWAYS;
29                 return 0;
30         case 0:
31                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;
32                 return 0;
33         }
34         if (!strcasecmp("if-asked", arg)) {
35                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_IF_ASKED;
36                 return 0;
37         }
38         die("bad %s argument: %s", opt->long_name, arg);
39 }
40
41 static void feed_object(const struct object_id *oid, FILE *fh, int negative)
42 {
43         if (negative &&
44             !has_object_file_with_flags(oid, OBJECT_INFO_SKIP_FETCH_OBJECT))
45                 return;
46
47         if (negative)
48                 putc('^', fh);
49         fputs(oid_to_hex(oid), fh);
50         putc('\n', fh);
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 oid_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         struct child_process po = CHILD_PROCESS_INIT;
64         FILE *po_in;
65         int i;
66         int rc;
67
68         argv_array_push(&po.args, "pack-objects");
69         argv_array_push(&po.args, "--all-progress-implied");
70         argv_array_push(&po.args, "--revs");
71         argv_array_push(&po.args, "--stdout");
72         if (args->use_thin_pack)
73                 argv_array_push(&po.args, "--thin");
74         if (args->use_ofs_delta)
75                 argv_array_push(&po.args, "--delta-base-offset");
76         if (args->quiet || !args->progress)
77                 argv_array_push(&po.args, "-q");
78         if (args->progress)
79                 argv_array_push(&po.args, "--progress");
80         if (is_repository_shallow(the_repository))
81                 argv_array_push(&po.args, "--shallow");
82         po.in = -1;
83         po.out = args->stateless_rpc ? -1 : fd;
84         po.git_cmd = 1;
85         if (start_command(&po))
86                 die_errno("git pack-objects failed");
87
88         /*
89          * We feed the pack-objects we just spawned with revision
90          * parameters by writing to the pipe.
91          */
92         po_in = xfdopen(po.in, "w");
93         for (i = 0; i < extra->nr; i++)
94                 feed_object(&extra->oid[i], po_in, 1);
95
96         while (refs) {
97                 if (!is_null_oid(&refs->old_oid))
98                         feed_object(&refs->old_oid, po_in, 1);
99                 if (!is_null_oid(&refs->new_oid))
100                         feed_object(&refs->new_oid, po_in, 0);
101                 refs = refs->next;
102         }
103
104         fflush(po_in);
105         if (ferror(po_in))
106                 die_errno("error writing to pack-objects");
107         fclose(po_in);
108
109         if (args->stateless_rpc) {
110                 char *buf = xmalloc(LARGE_PACKET_MAX);
111                 while (1) {
112                         ssize_t n = xread(po.out, buf, LARGE_PACKET_MAX);
113                         if (n <= 0)
114                                 break;
115                         send_sideband(fd, -1, buf, n, LARGE_PACKET_MAX);
116                 }
117                 free(buf);
118                 close(po.out);
119                 po.out = -1;
120         }
121
122         rc = finish_command(&po);
123         if (rc) {
124                 /*
125                  * For a normal non-zero exit, we assume pack-objects wrote
126                  * something useful to stderr. For death by signal, though,
127                  * we should mention it to the user. The exception is SIGPIPE
128                  * (141), because that's a normal occurrence if the remote end
129                  * hangs up (and we'll report that by trying to read the unpack
130                  * status).
131                  */
132                 if (rc > 128 && rc != 141)
133                         error("pack-objects died of signal %d", rc - 128);
134                 return -1;
135         }
136         return 0;
137 }
138
139 static int receive_unpack_status(struct packet_reader *reader)
140 {
141         if (packet_reader_read(reader) != PACKET_READ_NORMAL)
142                 return error(_("unexpected flush packet while reading remote unpack status"));
143         if (!skip_prefix(reader->line, "unpack ", &reader->line))
144                 return error(_("unable to parse remote unpack status: %s"), reader->line);
145         if (strcmp(reader->line, "ok"))
146                 return error(_("remote unpack failed: %s"), reader->line);
147         return 0;
148 }
149
150 static int receive_status(struct packet_reader *reader, struct ref *refs)
151 {
152         struct ref *hint;
153         int ret;
154
155         hint = NULL;
156         ret = receive_unpack_status(reader);
157         while (1) {
158                 const char *refname;
159                 char *msg;
160                 if (packet_reader_read(reader) != PACKET_READ_NORMAL)
161                         break;
162                 if (!starts_with(reader->line, "ok ") && !starts_with(reader->line, "ng ")) {
163                         error("invalid ref status from remote: %s", reader->line);
164                         ret = -1;
165                         break;
166                 }
167
168                 refname = reader->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 (reader->line[0] == 'o' && reader->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         if (async_with_fork())
206                 close(fd[1]);
207         ret = recv_sideband("send-pack", fd[0], out);
208         close(out);
209         return ret;
210 }
211
212 static int advertise_shallow_grafts_cb(const struct commit_graft *graft, void *cb)
213 {
214         struct strbuf *sb = cb;
215         if (graft->nr_parent == -1)
216                 packet_buf_write(sb, "shallow %s\n", oid_to_hex(&graft->oid));
217         return 0;
218 }
219
220 static void advertise_shallow_grafts_buf(struct strbuf *sb)
221 {
222         if (!is_repository_shallow(the_repository))
223                 return;
224         for_each_commit_graft(advertise_shallow_grafts_cb, sb);
225 }
226
227 #define CHECK_REF_NO_PUSH -1
228 #define CHECK_REF_STATUS_REJECTED -2
229 #define CHECK_REF_UPTODATE -3
230 static int check_to_send_update(const struct ref *ref, const struct send_pack_args *args)
231 {
232         if (!ref->peer_ref && !args->send_mirror)
233                 return CHECK_REF_NO_PUSH;
234
235         /* Check for statuses set by set_ref_status_for_push() */
236         switch (ref->status) {
237         case REF_STATUS_REJECT_NONFASTFORWARD:
238         case REF_STATUS_REJECT_ALREADY_EXISTS:
239         case REF_STATUS_REJECT_FETCH_FIRST:
240         case REF_STATUS_REJECT_NEEDS_FORCE:
241         case REF_STATUS_REJECT_STALE:
242         case REF_STATUS_REJECT_NODELETE:
243                 return CHECK_REF_STATUS_REJECTED;
244         case REF_STATUS_UPTODATE:
245                 return CHECK_REF_UPTODATE;
246         default:
247                 return 0;
248         }
249 }
250
251 /*
252  * the beginning of the next line, or the end of buffer.
253  *
254  * NEEDSWORK: perhaps move this to git-compat-util.h or somewhere and
255  * convert many similar uses found by "git grep -A4 memchr".
256  */
257 static const char *next_line(const char *line, size_t len)
258 {
259         const char *nl = memchr(line, '\n', len);
260         if (!nl)
261                 return line + len; /* incomplete line */
262         return nl + 1;
263 }
264
265 static int generate_push_cert(struct strbuf *req_buf,
266                               const struct ref *remote_refs,
267                               struct send_pack_args *args,
268                               const char *cap_string,
269                               const char *push_cert_nonce)
270 {
271         const struct ref *ref;
272         struct string_list_item *item;
273         char *signing_key = xstrdup(get_signing_key());
274         const char *cp, *np;
275         struct strbuf cert = STRBUF_INIT;
276         int update_seen = 0;
277
278         strbuf_addstr(&cert, "certificate version 0.1\n");
279         strbuf_addf(&cert, "pusher %s ", signing_key);
280         datestamp(&cert);
281         strbuf_addch(&cert, '\n');
282         if (args->url && *args->url) {
283                 char *anon_url = transport_anonymize_url(args->url);
284                 strbuf_addf(&cert, "pushee %s\n", anon_url);
285                 free(anon_url);
286         }
287         if (push_cert_nonce[0])
288                 strbuf_addf(&cert, "nonce %s\n", push_cert_nonce);
289         if (args->push_options)
290                 for_each_string_list_item(item, args->push_options)
291                         strbuf_addf(&cert, "push-option %s\n", item->string);
292         strbuf_addstr(&cert, "\n");
293
294         for (ref = remote_refs; ref; ref = ref->next) {
295                 if (check_to_send_update(ref, args) < 0)
296                         continue;
297                 update_seen = 1;
298                 strbuf_addf(&cert, "%s %s %s\n",
299                             oid_to_hex(&ref->old_oid),
300                             oid_to_hex(&ref->new_oid),
301                             ref->name);
302         }
303         if (!update_seen)
304                 goto free_return;
305
306         if (sign_buffer(&cert, &cert, signing_key))
307                 die(_("failed to sign the push certificate"));
308
309         packet_buf_write(req_buf, "push-cert%c%s", 0, cap_string);
310         for (cp = cert.buf; cp < cert.buf + cert.len; cp = np) {
311                 np = next_line(cp, cert.buf + cert.len - cp);
312                 packet_buf_write(req_buf,
313                                  "%.*s", (int)(np - cp), cp);
314         }
315         packet_buf_write(req_buf, "push-cert-end\n");
316
317 free_return:
318         free(signing_key);
319         strbuf_release(&cert);
320         return update_seen;
321 }
322
323
324 static int atomic_push_failure(struct send_pack_args *args,
325                                struct ref *remote_refs,
326                                struct ref *failing_ref)
327 {
328         struct ref *ref;
329         /* Mark other refs as failed */
330         for (ref = remote_refs; ref; ref = ref->next) {
331                 if (!ref->peer_ref && !args->send_mirror)
332                         continue;
333
334                 switch (ref->status) {
335                 case REF_STATUS_EXPECTING_REPORT:
336                         ref->status = REF_STATUS_ATOMIC_PUSH_FAILED;
337                         continue;
338                 default:
339                         break; /* do nothing */
340                 }
341         }
342         return error("atomic push failed for ref %s. status: %d\n",
343                      failing_ref->name, failing_ref->status);
344 }
345
346 #define NONCE_LEN_LIMIT 256
347
348 static void reject_invalid_nonce(const char *nonce, int len)
349 {
350         int i = 0;
351
352         if (NONCE_LEN_LIMIT <= len)
353                 die("the receiving end asked to sign an invalid nonce <%.*s>",
354                     len, nonce);
355
356         for (i = 0; i < len; i++) {
357                 int ch = nonce[i] & 0xFF;
358                 if (isalnum(ch) ||
359                     ch == '-' || ch == '.' ||
360                     ch == '/' || ch == '+' ||
361                     ch == '=' || ch == '_')
362                         continue;
363                 die("the receiving end asked to sign an invalid nonce <%.*s>",
364                     len, nonce);
365         }
366 }
367
368 int send_pack(struct send_pack_args *args,
369               int fd[], struct child_process *conn,
370               struct ref *remote_refs,
371               struct oid_array *extra_have)
372 {
373         int in = fd[0];
374         int out = fd[1];
375         struct strbuf req_buf = STRBUF_INIT;
376         struct strbuf cap_buf = STRBUF_INIT;
377         struct ref *ref;
378         int need_pack_data = 0;
379         int allow_deleting_refs = 0;
380         int status_report = 0;
381         int use_sideband = 0;
382         int quiet_supported = 0;
383         int agent_supported = 0;
384         int use_atomic = 0;
385         int atomic_supported = 0;
386         int use_push_options = 0;
387         int push_options_supported = 0;
388         unsigned cmds_sent = 0;
389         int ret;
390         struct async demux;
391         const char *push_cert_nonce = NULL;
392         struct packet_reader reader;
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(the_repository))) {
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         packet_reader_init(&reader, in, NULL, 0,
563                            PACKET_READ_CHOMP_NEWLINE |
564                            PACKET_READ_DIE_ON_ERR_PACKET);
565
566         if (need_pack_data && cmds_sent) {
567                 if (pack_objects(out, remote_refs, extra_have, args) < 0) {
568                         for (ref = remote_refs; ref; ref = ref->next)
569                                 ref->status = REF_STATUS_NONE;
570                         if (args->stateless_rpc)
571                                 close(out);
572                         if (git_connection_is_socket(conn))
573                                 shutdown(fd[0], SHUT_WR);
574
575                         /*
576                          * Do not even bother with the return value; we know we
577                          * are failing, and just want the error() side effects.
578                          */
579                         if (status_report)
580                                 receive_unpack_status(&reader);
581
582                         if (use_sideband) {
583                                 close(demux.out);
584                                 finish_async(&demux);
585                         }
586                         fd[1] = -1;
587                         return -1;
588                 }
589                 if (!args->stateless_rpc)
590                         /* Closed by pack_objects() via start_command() */
591                         fd[1] = -1;
592         }
593         if (args->stateless_rpc && cmds_sent)
594                 packet_flush(out);
595
596         if (status_report && cmds_sent)
597                 ret = receive_status(&reader, remote_refs);
598         else
599                 ret = 0;
600         if (args->stateless_rpc)
601                 packet_flush(out);
602
603         if (use_sideband && cmds_sent) {
604                 close(demux.out);
605                 if (finish_async(&demux)) {
606                         error("error in sideband demultiplexer");
607                         ret = -1;
608                 }
609         }
610
611         if (ret < 0)
612                 return ret;
613
614         if (args->porcelain)
615                 return 0;
616
617         for (ref = remote_refs; ref; ref = ref->next) {
618                 switch (ref->status) {
619                 case REF_STATUS_NONE:
620                 case REF_STATUS_UPTODATE:
621                 case REF_STATUS_OK:
622                         break;
623                 default:
624                         return -1;
625                 }
626         }
627         return 0;
628 }