1 /*
2  * Copyright (c) 2018, 2019 Stefan Sperling <stsp@openbsd.org>
3  * Copyright (c) 2019, Ori Bernstein <ori@openbsd.org>
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 /*
19  * All code runs under the same UID but sensitive code paths are
20  * run in a separate process with tighter pledge(2) promises.
21  * Data is communicated between processes via imsg_flush(3) and imsg_read(3).
22  * This behaviour is transparent to users of the library.
23  *
24  * We generally transmit data in imsg buffers, split across several messages
25  * if necessary. File descriptors are used in cases where this is impractical,
26  * such as when accessing pack files or when transferring large blobs.
27  *
28  * We exec(2) after a fork(2). Parts of our library functionality are
29  * accessible via separate executables in a libexec directory.
30  */
31 
32 #define GOT_IMSG_FD_CHILD (STDERR_FILENO + 1)
33 
34 #ifndef GOT_LIBEXECDIR
35 #define GOT_LIBEXECDIR /usr/local/bin
36 #endif
37 
38 /* Names of helper programs in libexec directory */
39 #define GOT_PROG_READ_OBJECT	got-read-object
40 #define GOT_PROG_READ_TREE	got-read-tree
41 #define GOT_PROG_READ_COMMIT	got-read-commit
42 #define GOT_PROG_READ_BLOB	got-read-blob
43 #define GOT_PROG_READ_TAG	got-read-tag
44 #define GOT_PROG_READ_PACK	got-read-pack
45 #define GOT_PROG_READ_GITCONFIG	got-read-gitconfig
46 #define GOT_PROG_READ_GOTCONFIG	got-read-gotconfig
47 #define GOT_PROG_READ_PATCH	got-read-patch
48 #define GOT_PROG_FETCH_PACK	got-fetch-pack
49 #define GOT_PROG_INDEX_PACK	got-index-pack
50 #define GOT_PROG_SEND_PACK	got-send-pack
51 
52 #define GOT_STRINGIFY(x) #x
53 #define GOT_STRINGVAL(x) GOT_STRINGIFY(x)
54 
55 /* Paths to helper programs in libexec directory */
56 #define GOT_PATH_PROG_READ_OBJECT \
57 	GOT_STRINGVAL(GOT_LIBEXECDIR) "/" GOT_STRINGVAL(GOT_PROG_READ_OBJECT)
58 #define GOT_PATH_PROG_READ_TREE \
59 	GOT_STRINGVAL(GOT_LIBEXECDIR) "/" GOT_STRINGVAL(GOT_PROG_READ_TREE)
60 #define GOT_PATH_PROG_READ_COMMIT \
61 	GOT_STRINGVAL(GOT_LIBEXECDIR) "/" GOT_STRINGVAL(GOT_PROG_READ_COMMIT)
62 #define GOT_PATH_PROG_READ_BLOB \
63 	GOT_STRINGVAL(GOT_LIBEXECDIR) "/" GOT_STRINGVAL(GOT_PROG_READ_BLOB)
64 #define GOT_PATH_PROG_READ_TAG \
65 	GOT_STRINGVAL(GOT_LIBEXECDIR) "/" GOT_STRINGVAL(GOT_PROG_READ_TAG)
66 #define GOT_PATH_PROG_READ_PACK \
67 	GOT_STRINGVAL(GOT_LIBEXECDIR) "/" GOT_STRINGVAL(GOT_PROG_READ_PACK)
68 #define GOT_PATH_PROG_READ_GITCONFIG \
69 	GOT_STRINGVAL(GOT_LIBEXECDIR) "/" GOT_STRINGVAL(GOT_PROG_READ_GITCONFIG)
70 #define GOT_PATH_PROG_READ_GOTCONFIG \
71 	GOT_STRINGVAL(GOT_LIBEXECDIR) "/" GOT_STRINGVAL(GOT_PROG_READ_GOTCONFIG)
72 #define GOT_PATH_PROG_READ_PATCH \
73 	GOT_STRINGVAL(GOT_LIBEXECDIR) "/" GOT_STRINGVAL(GOT_PROG_READ_PATCH)
74 #define GOT_PATH_PROG_FETCH_PACK \
75 	GOT_STRINGVAL(GOT_LIBEXECDIR) "/" GOT_STRINGVAL(GOT_PROG_FETCH_PACK)
76 #define GOT_PATH_PROG_SEND_PACK \
77 	GOT_STRINGVAL(GOT_LIBEXECDIR) "/" GOT_STRINGVAL(GOT_PROG_SEND_PACK)
78 #define GOT_PATH_PROG_INDEX_PACK \
79 	GOT_STRINGVAL(GOT_LIBEXECDIR) "/" GOT_STRINGVAL(GOT_PROG_INDEX_PACK)
80 
81 enum got_imsg_type {
82 	/* An error occured while processing a request. */
83 	GOT_IMSG_ERROR,
84 
85 	/* Stop the child process. */
86 	GOT_IMSG_STOP,
87 
88 	/*
89 	 * Messages concerned with read access to objects in a repository.
90 	 * Object and pack files are opened by the main process, where
91 	 * data may be read as a byte string but without any interpretation.
92 	 * Decompression and parsing of object and pack files occurs in a
93 	 * separate process which runs under pledge("stdio recvfd").
94 	 * This sandboxes our own repository parsing code, as well as zlib.
95 	 */
96 	GOT_IMSG_OBJECT_REQUEST,
97 	GOT_IMSG_OBJECT,
98 	GOT_IMSG_COMMIT_REQUEST,
99 	GOT_IMSG_COMMIT,
100 	GOT_IMSG_COMMIT_LOGMSG,
101 	GOT_IMSG_TREE_REQUEST,
102 	GOT_IMSG_TREE,
103 	GOT_IMSG_TREE_ENTRIES,
104 	GOT_IMSG_BLOB_REQUEST,
105 	GOT_IMSG_BLOB_OUTFD,
106 	GOT_IMSG_BLOB,
107 	GOT_IMSG_TAG_REQUEST,
108 	GOT_IMSG_TAG,
109 	GOT_IMSG_TAG_TAGMSG,
110 
111 	/* Messages related to networking. */
112 	GOT_IMSG_FETCH_REQUEST,
113 	GOT_IMSG_FETCH_HAVE_REF,
114 	GOT_IMSG_FETCH_WANTED_BRANCH,
115 	GOT_IMSG_FETCH_WANTED_REF,
116 	GOT_IMSG_FETCH_OUTFD,
117 	GOT_IMSG_FETCH_SYMREFS,
118 	GOT_IMSG_FETCH_REF,
119 	GOT_IMSG_FETCH_SERVER_PROGRESS,
120 	GOT_IMSG_FETCH_DOWNLOAD_PROGRESS,
121 	GOT_IMSG_FETCH_DONE,
122 	GOT_IMSG_IDXPACK_REQUEST,
123 	GOT_IMSG_IDXPACK_OUTFD,
124 	GOT_IMSG_IDXPACK_PROGRESS,
125 	GOT_IMSG_IDXPACK_DONE,
126 	GOT_IMSG_SEND_REQUEST,
127 	GOT_IMSG_SEND_REF,
128 	GOT_IMSG_SEND_REMOTE_REF,
129 	GOT_IMSG_SEND_REF_STATUS,
130 	GOT_IMSG_SEND_PACK_REQUEST,
131 	GOT_IMSG_SEND_PACKFD,
132 	GOT_IMSG_SEND_UPLOAD_PROGRESS,
133 	GOT_IMSG_SEND_DONE,
134 
135 	/* Messages related to pack files. */
136 	GOT_IMSG_PACKIDX,
137 	GOT_IMSG_PACK,
138 	GOT_IMSG_PACKED_OBJECT_REQUEST,
139 	GOT_IMSG_COMMIT_TRAVERSAL_REQUEST,
140 	GOT_IMSG_TRAVERSED_COMMITS,
141 	GOT_IMSG_COMMIT_TRAVERSAL_DONE,
142 	GOT_IMSG_OBJECT_ENUMERATION_REQUEST,
143 	GOT_IMSG_ENUMERATED_COMMIT,
144 	GOT_IMSG_ENUMERATED_TREE,
145 	GOT_IMSG_TREE_ENUMERATION_DONE,
146 	GOT_IMSG_OBJECT_ENUMERATION_DONE,
147 	GOT_IMSG_OBJECT_ENUMERATION_INCOMPLETE,
148 
149 	/* Message sending file descriptor to a temporary file. */
150 	GOT_IMSG_TMPFD,
151 
152 	/* Messages related to gitconfig files. */
153 	GOT_IMSG_GITCONFIG_PARSE_REQUEST,
154 	GOT_IMSG_GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST,
155 	GOT_IMSG_GITCONFIG_REPOSITORY_EXTENSIONS_REQUEST,
156 	GOT_IMSG_GITCONFIG_AUTHOR_NAME_REQUEST,
157 	GOT_IMSG_GITCONFIG_AUTHOR_EMAIL_REQUEST,
158 	GOT_IMSG_GITCONFIG_REMOTES_REQUEST,
159 	GOT_IMSG_GITCONFIG_INT_VAL,
160 	GOT_IMSG_GITCONFIG_STR_VAL,
161 	GOT_IMSG_GITCONFIG_PAIR,
162 	GOT_IMSG_GITCONFIG_REMOTES,
163 	GOT_IMSG_GITCONFIG_REMOTE,
164 	GOT_IMSG_GITCONFIG_OWNER_REQUEST,
165 	GOT_IMSG_GITCONFIG_OWNER,
166 
167 	/* Messages related to gotconfig files. */
168 	GOT_IMSG_GOTCONFIG_PARSE_REQUEST,
169 	GOT_IMSG_GOTCONFIG_AUTHOR_REQUEST,
170 	GOT_IMSG_GOTCONFIG_ALLOWEDSIGNERS_REQUEST,
171 	GOT_IMSG_GOTCONFIG_REVOKEDSIGNERS_REQUEST,
172 	GOT_IMSG_GOTCONFIG_SIGNERID_REQUEST,
173 	GOT_IMSG_GOTCONFIG_REMOTES_REQUEST,
174 	GOT_IMSG_GOTCONFIG_INT_VAL,
175 	GOT_IMSG_GOTCONFIG_STR_VAL,
176 	GOT_IMSG_GOTCONFIG_REMOTES,
177 	GOT_IMSG_GOTCONFIG_REMOTE,
178 
179 	/* Raw object access. Uncompress object data but do not parse it. */
180 	GOT_IMSG_RAW_OBJECT_REQUEST,
181 	GOT_IMSG_RAW_OBJECT_OUTFD,
182 	GOT_IMSG_PACKED_RAW_OBJECT_REQUEST,
183 	GOT_IMSG_RAW_OBJECT,
184 
185 	/* Read raw delta data from pack files. */
186 	GOT_IMSG_RAW_DELTA_OUTFD,
187 	GOT_IMSG_RAW_DELTA_REQUEST,
188 	GOT_IMSG_RAW_DELTA,
189 
190 	/* Re-use deltas found in a pack file. */
191 	GOT_IMSG_DELTA_REUSE_REQUEST,
192 	GOT_IMSG_REUSED_DELTAS,
193 	GOT_IMSG_DELTA_REUSE_DONE,
194 
195 	/* Commit coloring in got-read-pack. */
196 	GOT_IMSG_COMMIT_PAINTING_INIT,
197 	GOT_IMSG_COMMIT_PAINTING_REQUEST,
198 	GOT_IMSG_PAINTED_COMMITS,
199 	GOT_IMSG_COMMIT_PAINTING_DONE,
200 
201 	/* Transfer a list of object IDs. */
202 	GOT_IMSG_OBJ_ID_LIST,
203 	GOT_IMSG_OBJ_ID_LIST_DONE,
204 
205 	/* Messages related to patch files. */
206 	GOT_IMSG_PATCH_FILE,
207 	GOT_IMSG_PATCH_HUNK,
208 	GOT_IMSG_PATCH_DONE,
209 	GOT_IMSG_PATCH_LINE,
210 	GOT_IMSG_PATCH,
211 	GOT_IMSG_PATCH_EOF,
212 };
213 
214 /* Structure for GOT_IMSG_ERROR. */
215 struct got_imsg_error {
216 	int code; /* an error code from got_error.h */
217 	int errno_code; /* in case code equals GOT_ERR_ERRNO */
218 } __attribute__((__packed__));
219 
220 /*
221  * Structure for GOT_IMSG_TREE_REQUEST and GOT_IMSG_OBJECT data.
222  */
223 struct got_imsg_object {
224 	struct got_object_id id;
225 
226 	/* These fields are the same as in struct got_object. */
227 	int type;
228 	int flags;
229 	size_t hdrlen;
230 	size_t size;
231 	off_t pack_offset;
232 	int pack_idx;
233 }  __attribute__((__packed__));
234 
235 /* Structure for GOT_IMSG_COMMIT data. */
236 struct got_imsg_commit_object {
237 	struct got_object_id tree_id;
238 	size_t author_len;
239 	time_t author_time;
240 	time_t author_gmtoff;
241 	size_t committer_len;
242 	time_t committer_time;
243 	time_t committer_gmtoff;
244 	size_t logmsg_len;
245 	int nparents;
246 
247 	/*
248 	 * Followed by author_len + committer_len data bytes
249 	 */
250 
251 	/* Followed by 'nparents' struct got_object_id */
252 
253 	/*
254 	 * Followed by 'logmsg_len' bytes of commit log message data in
255 	 * one or more GOT_IMSG_COMMIT_LOGMSG messages.
256 	 */
257 } __attribute__((__packed__));
258 
259 struct got_imsg_tree_entry {
260 	char id[SHA1_DIGEST_LENGTH];
261 	mode_t mode;
262 	size_t namelen;
263 	/* Followed by namelen bytes of entry's name, not NUL-terminated. */
264 } __attribute__((__packed__));
265 
266 /* Structure for GOT_IMSG_TREE_ENTRIES. */
267 struct got_imsg_tree_entries {
268 	size_t nentries; /* Number of tree entries contained in this message. */
269 
270 	/* Followed by nentries * struct got_imsg_tree_entry */
271 };
272 
273 /* Structure for GOT_IMSG_TREE_OBJECT_REPLY data. */
274 struct got_imsg_tree_object {
275 	int nentries; /* This many tree entries follow. */
276 };
277 
278 /* Structure for GOT_IMSG_BLOB. */
279 struct got_imsg_blob {
280 	size_t size;
281 	size_t hdrlen;
282 
283 	/*
284 	 * If size <= GOT_PRIVSEP_INLINE_BLOB_DATA_MAX, blob data follows
285 	 * in the imsg buffer. Otherwise, blob data has been written to a
286 	 * file descriptor passed via the GOT_IMSG_BLOB_OUTFD imsg.
287 	 */
288 #define GOT_PRIVSEP_INLINE_BLOB_DATA_MAX \
289 	(MAX_IMSGSIZE - IMSG_HEADER_SIZE - sizeof(struct got_imsg_blob))
290 };
291 
292 /* Structure for GOT_IMSG_RAW_OBJECT. */
293 struct got_imsg_raw_obj {
294 	off_t size;
295 	size_t hdrlen;
296 
297 	/*
298 	 * If size <= GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX, object data follows
299 	 * in the imsg buffer. Otherwise, object data has been written to a
300 	 * file descriptor passed via the GOT_IMSG_RAW_OBJECT_OUTFD imsg.
301 	 */
302 #define GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX \
303 	(MAX_IMSGSIZE - IMSG_HEADER_SIZE - sizeof(struct got_imsg_raw_obj))
304 };
305 
306 /* Structure for GOT_IMSG_RAW_DELTA. */
307 struct got_imsg_raw_delta {
308 	struct got_object_id base_id;
309 	uint64_t base_size;
310 	uint64_t result_size;
311 	off_t delta_size;
312 	off_t delta_compressed_size;
313 	off_t delta_offset;
314 	off_t delta_out_offset;
315 
316 	/*
317 	 * Delta data has been written at delta_out_offset to the file
318 	 * descriptor passed via the GOT_IMSG_RAW_DELTA_OUTFD imsg.
319 	 */
320 };
321 
322 /* Structures for GOT_IMSG_REUSED_DELTAS. */
323 struct got_imsg_reused_delta {
324 	struct got_object_id id;
325 	struct got_object_id base_id;
326 	uint64_t base_size;
327 	uint64_t result_size;
328 	off_t delta_size;
329 	off_t delta_compressed_size;
330 	off_t delta_offset;
331 };
332 struct got_imsg_reused_deltas {
333 	size_t ndeltas;
334 
335 	/*
336 	 * Followed by ndeltas * struct got_imsg_reused_delta.
337 	 */
338 
339 #define GOT_IMSG_REUSED_DELTAS_MAX_NDELTAS \
340 	((MAX_IMSGSIZE - IMSG_HEADER_SIZE - \
341 	sizeof(struct got_imsg_reused_deltas)) \
342 	/ sizeof(struct got_imsg_reused_delta))
343 };
344 
345 /* Structure for GOT_IMSG_COMMIT_PAINTING_REQUEST. */
346 struct got_imsg_commit_painting_request {
347 	uint8_t id[SHA1_DIGEST_LENGTH];
348 	int idx;
349 	int color;
350 } __attribute__((__packed__));
351 
352 /* Structure for GOT_IMSG_PAINTED_COMMITS. */
353 struct got_imsg_painted_commit {
354 	uint8_t id[SHA1_DIGEST_LENGTH];
355 	intptr_t color;
356 } __attribute__((__packed__));
357 
358 struct got_imsg_painted_commits {
359 	int ncommits;
360 	int present_in_pack;
361 	/*
362 	 * Followed by ncommits * struct got_imsg_painted_commit.
363 	 */
364 } __attribute__((__packed__));
365 
366 /* Structure for GOT_IMSG_TAG data. */
367 struct got_imsg_tag_object {
368 	uint8_t id[SHA1_DIGEST_LENGTH];
369 	int obj_type;
370 	size_t tag_len;
371 	size_t tagger_len;
372 	time_t tagger_time;
373 	time_t tagger_gmtoff;
374 	size_t tagmsg_len;
375 
376 	/*
377 	 * Followed by tag_len + tagger_len data bytes
378 	 */
379 
380 	/*
381 	 * Followed by 'tagmsg_len' bytes of tag message data in
382 	 * one or more GOT_IMSG_TAG_TAGMSG messages.
383 	 */
384 } __attribute__((__packed__));
385 
386 /* Structure for GOT_IMSG_FETCH_HAVE_REF data. */
387 struct got_imsg_fetch_have_ref {
388 	struct got_object_id id;
389 	size_t name_len;
390 	/* Followed by name_len data bytes. */
391 } __attribute__((__packed__));
392 
393 /* Structure for GOT_IMSG_FETCH_WANTED_BRANCH data. */
394 struct got_imsg_fetch_wanted_branch {
395 	size_t name_len;
396 	/* Followed by name_len data bytes. */
397 } __attribute__((__packed__));
398 
399 /* Structure for GOT_IMSG_FETCH_WANTED_REF data. */
400 struct got_imsg_fetch_wanted_ref {
401 	size_t name_len;
402 	/* Followed by name_len data bytes. */
403 } __attribute__((__packed__));
404 
405 /* Structure for GOT_IMSG_FETCH_REQUEST data. */
406 struct got_imsg_fetch_request {
407 	int fetch_all_branches;
408 	int list_refs_only;
409 	int verbosity;
410 	size_t worktree_branch_len;
411 	size_t n_have_refs;
412 	size_t n_wanted_branches;
413 	size_t n_wanted_refs;
414 	/* Followed by worktree_branch_len bytes of reference name. */
415 	/* Followed by n_have_refs GOT_IMSG_FETCH_HAVE_REF messages. */
416 	/* Followed by n_wanted_branches times GOT_IMSG_FETCH_WANTED_BRANCH. */
417 	/* Followed by n_wanted_refs times GOT_IMSG_FETCH_WANTED_REF. */
418 } __attribute__((__packed__));
419 
420 /* Structures for GOT_IMSG_FETCH_SYMREFS data. */
421 struct got_imsg_fetch_symref {
422 	size_t name_len;
423 	size_t target_len;
424 
425 	/*
426 	 * Followed by name_len + target_len data bytes.
427 	 */
428 } __attribute__((__packed__));
429 
430 struct got_imsg_fetch_symrefs {
431 	size_t nsymrefs;
432 
433 	/* Followed by nsymrefs times of got_imsg_fetch_symref data. */
434 } __attribute__((__packed__));
435 
436 /* Structure for GOT_IMSG_FETCH_REF data. */
437 struct got_imsg_fetch_ref {
438 	/* Describes a reference which will be fetched. */
439 	struct got_object_id refid;
440 	/* Followed by reference name in remaining data of imsg buffer. */
441 };
442 
443 /* Structure for GOT_IMSG_FETCH_DOWNLOAD_PROGRESS data. */
444 struct got_imsg_fetch_download_progress {
445 	/* Number of packfile data bytes downloaded so far. */
446 	off_t packfile_bytes;
447 };
448 
449 /* Structure for GOT_IMSG_SEND_REQUEST data. */
450 struct got_imsg_send_request {
451 	int verbosity;
452 	size_t nrefs;
453 	/* Followed by nrefs GOT_IMSG_SEND_REF messages. */
454 } __attribute__((__packed__));
455 
456 /* Structure for GOT_IMSG_SEND_UPLOAD_PROGRESS data. */
457 struct got_imsg_send_upload_progress {
458 	/* Number of packfile data bytes uploaded so far. */
459 	off_t packfile_bytes;
460 };
461 
462 /* Structure for GOT_IMSG_SEND_REF data. */
463 struct got_imsg_send_ref {
464 	struct got_object_id id;
465 	int delete;
466 	size_t name_len;
467 	/* Followed by name_len data bytes. */
468 } __attribute__((__packed__));
469 
470 /* Structure for GOT_IMSG_SEND_REMOTE_REF data. */
471 struct got_imsg_send_remote_ref {
472 	struct got_object_id id;
473 	size_t name_len;
474 	/* Followed by name_len data bytes. */
475 } __attribute__((__packed__));
476 
477 /* Structure for GOT_IMSG_SEND_REF_STATUS data. */
478 struct got_imsg_send_ref_status {
479 	int success;
480 	size_t name_len;
481 	size_t errmsg_len;
482 	/* Followed by name_len data bytes. */
483 	/* Followed by errmsg_len data bytes. */
484 } __attribute__((__packed__));
485 
486 /* Structure for GOT_IMSG_IDXPACK_REQUEST data. */
487 struct got_imsg_index_pack_request {
488 	uint8_t pack_hash[SHA1_DIGEST_LENGTH];
489 } __attribute__((__packed__));
490 
491 /* Structure for GOT_IMSG_IDXPACK_PROGRESS data. */
492 struct got_imsg_index_pack_progress {
493 	/* Total number of objects in pack file. */
494 	int nobj_total;
495 
496 	/* Number of objects indexed so far. */
497 	int nobj_indexed;
498 
499 	/* Number of non-deltified objects in pack file. */
500 	int nobj_loose;
501 
502 	/* Number of deltified objects resolved so far. */
503 	int nobj_resolved;
504 };
505 
506 /* Structure for GOT_IMSG_PACKIDX. */
507 struct got_imsg_packidx {
508 	size_t len;
509 	off_t packfile_size;
510 	/* Additionally, a file desciptor is passed via imsg. */
511 };
512 
513 /* Structure for GOT_IMSG_PACK. */
514 struct got_imsg_pack {
515 	char path_packfile[PATH_MAX];
516 	off_t filesize;
517 	/* Additionally, a file desciptor is passed via imsg. */
518 } __attribute__((__packed__));
519 
520 /*
521  * Structure for GOT_IMSG_OBJECT_REQUEST, GOT_IMSG_BLOB_REQUEST,
522  * GOT_IMSG_TREE_REQUEST, GOT_IMSG_COMMIT_REQUEST, and
523  * GOT_IMSG_TAG_REQUEST data.
524  */
525 struct got_object_id;
526 
527 /*
528  * Structure for GOT_IMSG_PACKED_OBJECT_REQUEST and
529  * GOT_IMSG_PACKED_RAW_OBJECT_REQUEST data.
530  */
531 struct got_imsg_packed_object {
532 	struct got_object_id id;
533 	int idx;
534 } __attribute__((__packed__));
535 
536 /*
537  * Structure for GOT_IMSG_DELTA data.
538  */
539 struct got_imsg_delta {
540 	/* These fields are the same as in struct got_delta. */
541 	off_t offset;
542 	size_t tslen;
543 	int type;
544 	size_t size;
545 	off_t data_offset;
546 };
547 
548 /*
549  * Structure for GOT_IMSG_RAW_DELTA_REQUEST data.
550  */
551 struct got_imsg_raw_delta_request {
552 	struct got_object_id id;
553 	int idx;
554 };
555 
556 /*
557  * Structure for GOT_IMSG_OBJ_ID_LIST data.
558  * Multiple such messages may be sent back-to-back, where each message
559  * contains a chunk of IDs. The entire list must be terminated with a
560  * GOT_IMSG_OBJ_ID_LIST_DONE message.
561  */
562 struct got_imsg_object_idlist {
563 	size_t nids;
564 
565 	/*
566 	 * Followed by nids * struct got_object_id.
567 	 */
568 
569 #define GOT_IMSG_OBJ_ID_LIST_MAX_NIDS \
570 	((MAX_IMSGSIZE - IMSG_HEADER_SIZE - \
571 	sizeof(struct got_imsg_object_idlist)) / sizeof(struct got_object_id))
572 };
573 
574 /* Structure for GOT_IMSG_COMMIT_TRAVERSAL_REQUEST  */
575 struct got_imsg_commit_traversal_request {
576 	uint8_t id[SHA1_DIGEST_LENGTH];
577 	int idx;
578 	size_t path_len;
579 	/* Followed by path_len bytes of path data */
580 } __attribute__((__packed__));
581 
582 /* Structure for GOT_IMSG_TRAVERSED_COMMITS  */
583 struct got_imsg_traversed_commits {
584 	size_t ncommits;
585 	/* Followed by ncommit IDs of SHA1_DIGEST_LENGTH each */
586 } __attribute__((__packed__));
587 
588 /* Structure for GOT_IMSG_ENUMERATED_COMMIT  */
589 struct got_imsg_enumerated_commit {
590 	uint8_t id[SHA1_DIGEST_LENGTH];
591 	time_t mtime;
592 } __attribute__((__packed__));
593 
594 /* Structure for GOT_IMSG_ENUMERATED_TREE */
595 struct got_imsg_enumerated_tree {
596 	uint8_t id[SHA1_DIGEST_LENGTH]; /* tree ID */
597 	int nentries;			/* number of tree entries */
598 
599 	/* Followed by tree's path in remaining data of imsg buffer. */
600 
601 	/* Followed by nentries * GOT_IMSG_TREE_ENTRY messages. */
602 } __attribute__((__packed__));
603 
604 /*
605  * Structure for GOT_IMSG_GOTCONFIG_REMOTE and
606  * GOT_IMSG_GOTCONFIG_REMOTE data.
607  */
608 struct got_imsg_remote {
609 	size_t name_len;
610 	size_t fetch_url_len;
611 	size_t send_url_len;
612 	int mirror_references;
613 	int fetch_all_branches;
614 	int nfetch_branches;
615 	int nsend_branches;
616 	int nfetch_refs;
617 
618 	/* Followed by name_len data bytes. */
619 	/* Followed by fetch_url_len + send_url_len data bytes. */
620 	/* Followed by nfetch_branches GOT_IMSG_GITCONFIG_STR_VAL messages. */
621 	/* Followed by nsend_branches GOT_IMSG_GITCONFIG_STR_VAL messages. */
622 	/* Followed by nfetch_refs GOT_IMSG_GITCONFIG_STR_VAL messages. */
623 } __attribute__((__packed__));
624 
625 /*
626  * Structure for GOT_IMSG_GITCONFIG_REMOTES data.
627  */
628 struct got_imsg_remotes {
629 	int nremotes; /* This many GOT_IMSG_GITCONFIG_REMOTE messages follow. */
630 };
631 
632 /*
633  * Structure for GOT_IMSG_GITCONFIG_PAIR.
634  */
635 struct got_imsg_gitconfig_pair {
636 	size_t	klen;
637 	size_t	vlen;
638 	/* Followed by klen data bytes of key string. */
639 	/* Followed by vlen data bytes of value string. */
640 };
641 
642 /*
643  * Structure for GOT_IMSG_PATCH data.
644  */
645 struct got_imsg_patch {
646 	int	git;
647 	int	xbit;
648 	char	old[PATH_MAX];
649 	char	new[PATH_MAX];
650 	char	cid[41];
651 	char	blob[41];
652 };
653 
654 /*
655  * Structure for GOT_IMSG_PATCH_HUNK data.
656  */
657 struct got_imsg_patch_hunk {
658 	int	oldfrom;
659 	int	oldlines;
660 	int	newfrom;
661 	int	newlines;
662 };
663 
664 struct got_remote_repo;
665 struct got_pack;
666 struct got_packidx;
667 struct got_pathlist_head;
668 
669 const struct got_error *got_send_ack(pid_t);
670 const struct got_error *got_privsep_wait_for_child(pid_t);
671 const struct got_error *got_privsep_flush_imsg(struct imsgbuf *);
672 const struct got_error *got_privsep_send_stop(int);
673 const struct got_error *got_privsep_recv_imsg(struct imsg *, struct imsgbuf *,
674     size_t);
675 void got_privsep_send_error(struct imsgbuf *, const struct got_error *);
676 const struct got_error *got_privsep_send_ack(struct imsgbuf *);
677 const struct got_error *got_privsep_wait_ack(struct imsgbuf *);
678 const struct got_error *got_privsep_send_obj_req(struct imsgbuf *, int,
679     struct got_object_id *);
680 const struct got_error *got_privsep_send_raw_obj_req(struct imsgbuf *, int,
681     struct got_object_id *);
682 const struct got_error *got_privsep_send_raw_obj_outfd(struct imsgbuf *, int);
683 const struct got_error *got_privsep_send_commit_req(struct imsgbuf *, int,
684     struct got_object_id *, int);
685 const struct got_error *got_privsep_send_tree_req(struct imsgbuf *, int,
686     struct got_object_id *, int);
687 const struct got_error *got_privsep_send_tag_req(struct imsgbuf *, int,
688     struct got_object_id *, int);
689 const struct got_error *got_privsep_send_blob_req(struct imsgbuf *, int,
690     struct got_object_id *, int);
691 const struct got_error *got_privsep_send_blob_outfd(struct imsgbuf *, int);
692 const struct got_error *got_privsep_send_tmpfd(struct imsgbuf *, int);
693 const struct got_error *got_privsep_send_obj(struct imsgbuf *,
694     struct got_object *);
695 const struct got_error *got_privsep_send_index_pack_req(struct imsgbuf *,
696     uint8_t *, int);
697 const struct got_error *got_privsep_send_index_pack_outfd(struct imsgbuf *,
698     int);
699 const struct got_error *got_privsep_recv_index_progress(int *, int *, int *,
700     int *, int *, struct imsgbuf *ibuf);
701 const struct got_error *got_privsep_send_fetch_req(struct imsgbuf *, int,
702     struct got_pathlist_head *, int, struct got_pathlist_head *,
703     struct got_pathlist_head *, int, const char *, int);
704 const struct got_error *got_privsep_send_fetch_outfd(struct imsgbuf *, int);
705 const struct got_error *got_privsep_recv_fetch_progress(int *,
706     struct got_object_id **, char **, struct got_pathlist_head *, char **,
707     off_t *, uint8_t *, struct imsgbuf *);
708 const struct got_error *got_privsep_send_send_req(struct imsgbuf *, int,
709     struct got_pathlist_head *, struct got_pathlist_head *, int);
710 const struct got_error *got_privsep_recv_send_remote_refs(
711     struct got_pathlist_head *, struct imsgbuf *);
712 const struct got_error *got_privsep_send_packfd(struct imsgbuf *, int);
713 const struct got_error *got_privsep_recv_send_progress(int *, off_t *,
714     int *, char **, char **, struct imsgbuf *);
715 const struct got_error *got_privsep_get_imsg_obj(struct got_object **,
716     struct imsg *, struct imsgbuf *);
717 const struct got_error *got_privsep_recv_obj(struct got_object **,
718     struct imsgbuf *);
719 const struct got_error *got_privsep_send_raw_obj(struct imsgbuf *, off_t,
720     size_t, uint8_t *);
721 const struct got_error *got_privsep_recv_raw_obj(uint8_t **, off_t *, size_t *,
722     struct imsgbuf *);
723 const struct got_error *got_privsep_send_commit(struct imsgbuf *,
724     struct got_commit_object *);
725 const struct got_error *got_privsep_recv_commit(struct got_commit_object **,
726     struct imsgbuf *);
727 const struct got_error *got_privsep_recv_tree(struct got_tree_object **,
728     struct imsgbuf *);
729 struct got_parsed_tree_entry;
730 const struct got_error *got_privsep_send_tree(struct imsgbuf *,
731     struct got_parsed_tree_entry *, int);
732 const struct got_error *got_privsep_send_blob(struct imsgbuf *, size_t, size_t,
733     const uint8_t *);
734 const struct got_error *got_privsep_recv_blob(uint8_t **, size_t *, size_t *,
735     struct imsgbuf *);
736 const struct got_error *got_privsep_send_tag(struct imsgbuf *,
737     struct got_tag_object *);
738 const struct got_error *got_privsep_recv_tag(struct got_tag_object **,
739     struct imsgbuf *);
740 const struct got_error *got_privsep_init_pack_child(struct imsgbuf *,
741     struct got_pack *, struct got_packidx *);
742 const struct got_error *got_privsep_send_packed_obj_req(struct imsgbuf *, int,
743     struct got_object_id *);
744 const struct got_error *got_privsep_send_packed_raw_obj_req(struct imsgbuf *,
745     int, struct got_object_id *);
746 const struct got_error *got_privsep_send_pack_child_ready(struct imsgbuf *);
747 
748 const struct got_error *got_privsep_send_gitconfig_parse_req(struct imsgbuf *,
749     int);
750 const struct got_error *
751     got_privsep_send_gitconfig_repository_format_version_req(struct imsgbuf *);
752 const struct got_error *got_privsep_send_gitconfig_repository_extensions_req(
753     struct imsgbuf *);
754 const struct got_error *got_privsep_send_gitconfig_author_name_req(
755     struct imsgbuf *);
756 const struct got_error *got_privsep_send_gitconfig_author_email_req(
757     struct imsgbuf *);
758 const struct got_error *got_privsep_send_gitconfig_remotes_req(
759     struct imsgbuf *);
760 const struct got_error *got_privsep_send_gitconfig_owner_req(struct imsgbuf *);
761 const struct got_error *got_privsep_recv_gitconfig_str(char **,
762     struct imsgbuf *);
763 const struct got_error *got_privsep_recv_gitconfig_pair(char **, char **,
764     struct imsgbuf *);
765 const struct got_error *got_privsep_recv_gitconfig_int(int *, struct imsgbuf *);
766 const struct got_error *got_privsep_recv_gitconfig_remotes(
767     struct got_remote_repo **, int *, struct imsgbuf *);
768 
769 const struct got_error *got_privsep_send_gotconfig_parse_req(struct imsgbuf *,
770     int);
771 const struct got_error *got_privsep_send_gotconfig_author_req(struct imsgbuf *);
772 const struct got_error *got_privsep_send_gotconfig_allowed_signers_req(
773     struct imsgbuf *);
774 const struct got_error *got_privsep_send_gotconfig_revoked_signers_req(
775     struct imsgbuf *);
776 const struct got_error *got_privsep_send_gotconfig_signer_id_req(
777     struct imsgbuf *);
778 const struct got_error *got_privsep_send_gotconfig_remotes_req(
779     struct imsgbuf *);
780 const struct got_error *got_privsep_recv_gotconfig_str(char **,
781     struct imsgbuf *);
782 const struct got_error *got_privsep_recv_gotconfig_remotes(
783     struct got_remote_repo **, int *, struct imsgbuf *);
784 
785 const struct got_error *got_privsep_send_commit_traversal_request(
786     struct imsgbuf *, struct got_object_id *, int, const char *);
787 const struct got_error *got_privsep_recv_traversed_commits(
788     struct got_commit_object **, struct got_object_id **,
789     struct got_object_id_queue *, struct imsgbuf *);
790 const struct got_error *got_privsep_send_enumerated_tree(size_t *,
791     struct imsgbuf *, struct got_object_id *, const char *,
792     struct got_parsed_tree_entry *, int);
793 const struct got_error *got_privsep_send_object_enumeration_request(
794     struct imsgbuf *);
795 const struct got_error *got_privsep_send_object_enumeration_done(
796     struct imsgbuf *);
797 const struct got_error *got_privsep_send_object_enumeration_incomplete(
798     struct imsgbuf *);
799 const struct got_error *got_privsep_send_enumerated_commit(struct imsgbuf *,
800     struct got_object_id *, time_t);
801 const struct got_error *got_privsep_recv_enumerated_objects(int *,
802     struct imsgbuf *, got_object_enumerate_commit_cb,
803     got_object_enumerate_tree_cb, void *, struct got_repository *);
804 
805 const struct got_error *got_privsep_send_raw_delta_req(struct imsgbuf *, int,
806     struct got_object_id *);
807 const struct got_error *got_privsep_send_raw_delta_outfd(struct imsgbuf *, int);
808 const struct got_error *got_privsep_send_raw_delta(struct imsgbuf *, uint64_t,
809     uint64_t,  off_t, off_t, off_t, off_t, struct got_object_id *);
810 const struct got_error *got_privsep_recv_raw_delta(uint64_t *, uint64_t *,
811     off_t *, off_t *, off_t *, off_t *, struct got_object_id **,
812     struct imsgbuf *);
813 
814 const struct got_error *got_privsep_send_object_idlist(struct imsgbuf *,
815     struct got_object_id **, size_t);
816 const struct got_error *got_privsep_send_object_idlist_done(struct imsgbuf *);
817 const struct got_error *got_privsep_recv_object_idlist(int *,
818     struct got_object_id **, size_t *, struct imsgbuf *);
819 
820 const struct got_error *got_privsep_send_delta_reuse_req(struct imsgbuf *);
821 const struct got_error *got_privsep_send_reused_deltas(struct imsgbuf *,
822     struct got_imsg_reused_delta *, size_t);
823 const struct got_error *got_privsep_send_reused_deltas_done(struct imsgbuf *);
824 const struct got_error *got_privsep_recv_reused_deltas(int *,
825     struct got_imsg_reused_delta *, size_t *, struct imsgbuf *);
826 
827 const struct got_error *got_privsep_init_commit_painting(struct imsgbuf *);
828 const struct got_error *got_privsep_send_painting_request(struct imsgbuf *,
829     int, struct got_object_id *, intptr_t);
830 typedef const struct got_error *(*got_privsep_recv_painted_commit_cb)(void *,
831     struct got_object_id *, intptr_t);
832 const struct got_error *got_privsep_send_painted_commits(struct imsgbuf *,
833     struct got_object_id_queue *, int *, int, int);
834 const struct got_error *got_privsep_send_painting_commits_done(struct imsgbuf *);
835 const struct got_error *got_privsep_recv_painted_commits(
836     struct got_object_id_queue *, got_privsep_recv_painted_commit_cb, void *,
837     struct imsgbuf *);
838 
839 void got_privsep_exec_child(int[2], const char *, const char *);