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/libexec
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_REMOTES,
162 	GOT_IMSG_GITCONFIG_REMOTE,
163 	GOT_IMSG_GITCONFIG_OWNER_REQUEST,
164 	GOT_IMSG_GITCONFIG_OWNER,
165 
166 	/* Messages related to gotconfig files. */
167 	GOT_IMSG_GOTCONFIG_PARSE_REQUEST,
168 	GOT_IMSG_GOTCONFIG_AUTHOR_REQUEST,
169 	GOT_IMSG_GOTCONFIG_ALLOWEDSIGNERS_REQUEST,
170 	GOT_IMSG_GOTCONFIG_REVOKEDSIGNERS_REQUEST,
171 	GOT_IMSG_GOTCONFIG_SIGNERID_REQUEST,
172 	GOT_IMSG_GOTCONFIG_REMOTES_REQUEST,
173 	GOT_IMSG_GOTCONFIG_INT_VAL,
174 	GOT_IMSG_GOTCONFIG_STR_VAL,
175 	GOT_IMSG_GOTCONFIG_REMOTES,
176 	GOT_IMSG_GOTCONFIG_REMOTE,
177 
178 	/* Raw object access. Uncompress object data but do not parse it. */
179 	GOT_IMSG_RAW_OBJECT_REQUEST,
180 	GOT_IMSG_RAW_OBJECT_OUTFD,
181 	GOT_IMSG_PACKED_RAW_OBJECT_REQUEST,
182 	GOT_IMSG_RAW_OBJECT,
183 
184 	/* Read raw delta data from pack files. */
185 	GOT_IMSG_RAW_DELTA_OUTFD,
186 	GOT_IMSG_RAW_DELTA_REQUEST,
187 	GOT_IMSG_RAW_DELTA,
188 
189 	/* Re-use deltas found in a pack file. */
190 	GOT_IMSG_DELTA_REUSE_REQUEST,
191 	GOT_IMSG_REUSED_DELTAS,
192 	GOT_IMSG_DELTA_REUSE_DONE,
193 
194 	/* Commit coloring in got-read-pack. */
195 	GOT_IMSG_COMMIT_PAINTING_INIT,
196 	GOT_IMSG_COMMIT_PAINTING_REQUEST,
197 	GOT_IMSG_PAINTED_COMMITS,
198 	GOT_IMSG_COMMIT_PAINTING_DONE,
199 
200 	/* Transfer a list of object IDs. */
201 	GOT_IMSG_OBJ_ID_LIST,
202 	GOT_IMSG_OBJ_ID_LIST_DONE,
203 
204 	/* Messages related to patch files. */
205 	GOT_IMSG_PATCH_FILE,
206 	GOT_IMSG_PATCH_HUNK,
207 	GOT_IMSG_PATCH_DONE,
208 	GOT_IMSG_PATCH_LINE,
209 	GOT_IMSG_PATCH,
210 	GOT_IMSG_PATCH_EOF,
211 };
212 
213 /* Structure for GOT_IMSG_ERROR. */
214 struct got_imsg_error {
215 	int code; /* an error code from got_error.h */
216 	int errno_code; /* in case code equals GOT_ERR_ERRNO */
217 } __attribute__((__packed__));
218 
219 /*
220  * Structure for GOT_IMSG_TREE_REQUEST and GOT_IMSG_OBJECT data.
221  */
222 struct got_imsg_object {
223 	uint8_t id[SHA1_DIGEST_LENGTH];
224 
225 	/* These fields are the same as in struct got_object. */
226 	int type;
227 	int flags;
228 	size_t hdrlen;
229 	size_t size;
230 	off_t pack_offset;
231 	int pack_idx;
232 }  __attribute__((__packed__));
233 
234 /* Structure for GOT_IMSG_COMMIT data. */
235 struct got_imsg_commit_object {
236 	uint8_t tree_id[SHA1_DIGEST_LENGTH];
237 	size_t author_len;
238 	time_t author_time;
239 	time_t author_gmtoff;
240 	size_t committer_len;
241 	time_t committer_time;
242 	time_t committer_gmtoff;
243 	size_t logmsg_len;
244 	int nparents;
245 
246 	/*
247 	 * Followed by author_len + committer_len data bytes
248 	 */
249 
250 	/* Followed by 'nparents' SHA1_DIGEST_LENGTH length strings */
251 
252 	/*
253 	 * Followed by 'logmsg_len' bytes of commit log message data in
254 	 * one or more GOT_IMSG_COMMIT_LOGMSG messages.
255 	 */
256 } __attribute__((__packed__));
257 
258 struct got_imsg_tree_entry {
259 	char id[SHA1_DIGEST_LENGTH];
260 	mode_t mode;
261 	size_t namelen;
262 	/* Followed by namelen bytes of entry's name, not NUL-terminated. */
263 } __attribute__((__packed__));
264 
265 /* Structure for GOT_IMSG_TREE_ENTRIES. */
266 struct got_imsg_tree_entries {
267 	size_t nentries; /* Number of tree entries contained in this message. */
268 
269 	/* Followed by nentries * struct got_imsg_tree_entry */
270 };
271 
272 /* Structure for GOT_IMSG_TREE_OBJECT_REPLY data. */
273 struct got_imsg_tree_object {
274 	int nentries; /* This many tree entries follow. */
275 };
276 
277 /* Structure for GOT_IMSG_BLOB. */
278 struct got_imsg_blob {
279 	size_t size;
280 	size_t hdrlen;
281 
282 	/*
283 	 * If size <= GOT_PRIVSEP_INLINE_BLOB_DATA_MAX, blob data follows
284 	 * in the imsg buffer. Otherwise, blob data has been written to a
285 	 * file descriptor passed via the GOT_IMSG_BLOB_OUTFD imsg.
286 	 */
287 #define GOT_PRIVSEP_INLINE_BLOB_DATA_MAX \
288 	(MAX_IMSGSIZE - IMSG_HEADER_SIZE - sizeof(struct got_imsg_blob))
289 };
290 
291 /* Structure for GOT_IMSG_RAW_OBJECT. */
292 struct got_imsg_raw_obj {
293 	off_t size;
294 	size_t hdrlen;
295 
296 	/*
297 	 * If size <= GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX, object data follows
298 	 * in the imsg buffer. Otherwise, object data has been written to a
299 	 * file descriptor passed via the GOT_IMSG_RAW_OBJECT_OUTFD imsg.
300 	 */
301 #define GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX \
302 	(MAX_IMSGSIZE - IMSG_HEADER_SIZE - sizeof(struct got_imsg_raw_obj))
303 };
304 
305 /* Structure for GOT_IMSG_RAW_DELTA. */
306 struct got_imsg_raw_delta {
307 	uint8_t base_id[SHA1_DIGEST_LENGTH];
308 	uint64_t base_size;
309 	uint64_t result_size;
310 	off_t delta_size;
311 	off_t delta_compressed_size;
312 	off_t delta_offset;
313 	off_t delta_out_offset;
314 
315 	/*
316 	 * Delta data has been written at delta_out_offset to the file
317 	 * descriptor passed via the GOT_IMSG_RAW_DELTA_OUTFD imsg.
318 	 */
319 };
320 
321 /* Structures for GOT_IMSG_REUSED_DELTAS. */
322 struct got_imsg_reused_delta {
323 	struct got_object_id id;
324 	struct got_object_id base_id;
325 	uint64_t base_size;
326 	uint64_t result_size;
327 	off_t delta_size;
328 	off_t delta_compressed_size;
329 	off_t delta_offset;
330 };
331 struct got_imsg_reused_deltas {
332 	size_t ndeltas;
333 
334 	/*
335 	 * Followed by ndeltas * struct got_imsg_reused_delta.
336 	 */
337 
338 #define GOT_IMSG_REUSED_DELTAS_MAX_NDELTAS \
339 	((MAX_IMSGSIZE - IMSG_HEADER_SIZE - \
340 	sizeof(struct got_imsg_reused_deltas)) \
341 	/ sizeof(struct got_imsg_reused_delta))
342 };
343 
344 /* Structure for GOT_IMSG_COMMIT_PAINTING_REQUEST. */
345 struct got_imsg_commit_painting_request {
346 	uint8_t id[SHA1_DIGEST_LENGTH];
347 	int idx;
348 	int color;
349 } __attribute__((__packed__));
350 
351 /* Structure for GOT_IMSG_PAINTED_COMMITS. */
352 struct got_imsg_painted_commit {
353 	uint8_t id[SHA1_DIGEST_LENGTH];
354 	intptr_t color;
355 } __attribute__((__packed__));
356 
357 struct got_imsg_painted_commits {
358 	int ncommits;
359 	int present_in_pack;
360 	/*
361 	 * Followed by ncommits * struct got_imsg_painted_commit.
362 	 */
363 } __attribute__((__packed__));
364 
365 /* Structure for GOT_IMSG_TAG data. */
366 struct got_imsg_tag_object {
367 	uint8_t id[SHA1_DIGEST_LENGTH];
368 	int obj_type;
369 	size_t tag_len;
370 	size_t tagger_len;
371 	time_t tagger_time;
372 	time_t tagger_gmtoff;
373 	size_t tagmsg_len;
374 
375 	/*
376 	 * Followed by tag_len + tagger_len data bytes
377 	 */
378 
379 	/*
380 	 * Followed by 'tagmsg_len' bytes of tag message data in
381 	 * one or more GOT_IMSG_TAG_TAGMSG messages.
382 	 */
383 } __attribute__((__packed__));
384 
385 /* Structure for GOT_IMSG_FETCH_HAVE_REF data. */
386 struct got_imsg_fetch_have_ref {
387 	uint8_t id[SHA1_DIGEST_LENGTH];
388 	size_t name_len;
389 	/* Followed by name_len data bytes. */
390 } __attribute__((__packed__));
391 
392 /* Structure for GOT_IMSG_FETCH_WANTED_BRANCH data. */
393 struct got_imsg_fetch_wanted_branch {
394 	size_t name_len;
395 	/* Followed by name_len data bytes. */
396 } __attribute__((__packed__));
397 
398 /* Structure for GOT_IMSG_FETCH_WANTED_REF data. */
399 struct got_imsg_fetch_wanted_ref {
400 	size_t name_len;
401 	/* Followed by name_len data bytes. */
402 } __attribute__((__packed__));
403 
404 /* Structure for GOT_IMSG_FETCH_REQUEST data. */
405 struct got_imsg_fetch_request {
406 	int fetch_all_branches;
407 	int list_refs_only;
408 	int verbosity;
409 	size_t n_have_refs;
410 	size_t n_wanted_branches;
411 	size_t n_wanted_refs;
412 	/* Followed by n_have_refs GOT_IMSG_FETCH_HAVE_REF messages. */
413 	/* Followed by n_wanted_branches times GOT_IMSG_FETCH_WANTED_BRANCH. */
414 	/* Followed by n_wanted_refs times GOT_IMSG_FETCH_WANTED_REF. */
415 } __attribute__((__packed__));
416 
417 /* Structures for GOT_IMSG_FETCH_SYMREFS data. */
418 struct got_imsg_fetch_symref {
419 	size_t name_len;
420 	size_t target_len;
421 
422 	/*
423 	 * Followed by name_len + target_len data bytes.
424 	 */
425 } __attribute__((__packed__));
426 
427 struct got_imsg_fetch_symrefs {
428 	size_t nsymrefs;
429 
430 	/* Followed by nsymrefs times of got_imsg_fetch_symref data. */
431 } __attribute__((__packed__));
432 
433 /* Structure for GOT_IMSG_FETCH_REF data. */
434 struct got_imsg_fetch_ref {
435 	/* Describes a reference which will be fetched. */
436 	uint8_t refid[SHA1_DIGEST_LENGTH];
437 	/* Followed by reference name in remaining data of imsg buffer. */
438 };
439 
440 /* Structure for GOT_IMSG_FETCH_DOWNLOAD_PROGRESS data. */
441 struct got_imsg_fetch_download_progress {
442 	/* Number of packfile data bytes downloaded so far. */
443 	off_t packfile_bytes;
444 };
445 
446 /* Structure for GOT_IMSG_SEND_REQUEST data. */
447 struct got_imsg_send_request {
448 	int verbosity;
449 	size_t nrefs;
450 	/* Followed by nrefs GOT_IMSG_SEND_REF messages. */
451 } __attribute__((__packed__));
452 
453 /* Structure for GOT_IMSG_SEND_UPLOAD_PROGRESS data. */
454 struct got_imsg_send_upload_progress {
455 	/* Number of packfile data bytes uploaded so far. */
456 	off_t packfile_bytes;
457 };
458 
459 /* Structure for GOT_IMSG_SEND_REF data. */
460 struct got_imsg_send_ref {
461 	uint8_t id[SHA1_DIGEST_LENGTH];
462 	int delete;
463 	size_t name_len;
464 	/* Followed by name_len data bytes. */
465 } __attribute__((__packed__));
466 
467 /* Structure for GOT_IMSG_SEND_REMOTE_REF data. */
468 struct got_imsg_send_remote_ref {
469 	uint8_t id[SHA1_DIGEST_LENGTH];
470 	size_t name_len;
471 	/* Followed by name_len data bytes. */
472 } __attribute__((__packed__));
473 
474 /* Structure for GOT_IMSG_SEND_REF_STATUS data. */
475 struct got_imsg_send_ref_status {
476 	int success;
477 	size_t name_len;
478 	size_t errmsg_len;
479 	/* Followed by name_len data bytes. */
480 	/* Followed by errmsg_len data bytes. */
481 } __attribute__((__packed__));
482 
483 /* Structure for GOT_IMSG_IDXPACK_REQUEST data. */
484 struct got_imsg_index_pack_request {
485 	uint8_t pack_hash[SHA1_DIGEST_LENGTH];
486 } __attribute__((__packed__));
487 
488 /* Structure for GOT_IMSG_IDXPACK_PROGRESS data. */
489 struct got_imsg_index_pack_progress {
490 	/* Total number of objects in pack file. */
491 	int nobj_total;
492 
493 	/* Number of objects indexed so far. */
494 	int nobj_indexed;
495 
496 	/* Number of non-deltified objects in pack file. */
497 	int nobj_loose;
498 
499 	/* Number of deltified objects resolved so far. */
500 	int nobj_resolved;
501 };
502 
503 /* Structure for GOT_IMSG_PACKIDX. */
504 struct got_imsg_packidx {
505 	size_t len;
506 	off_t packfile_size;
507 	/* Additionally, a file desciptor is passed via imsg. */
508 };
509 
510 /* Structure for GOT_IMSG_PACK. */
511 struct got_imsg_pack {
512 	char path_packfile[PATH_MAX];
513 	off_t filesize;
514 	/* Additionally, a file desciptor is passed via imsg. */
515 } __attribute__((__packed__));
516 
517 /*
518  * Structure for GOT_IMSG_OBJECT_REQUEST, GOT_IMSG_BLOB_REQUEST,
519  * GOT_IMSG_TREE_REQUEST, GOT_IMSG_COMMIT_REQUEST, and
520  * GOT_IMSG_TAG_REQUEST data.
521  */
522 struct got_object_id;
523 
524 /*
525  * Structure for GOT_IMSG_PACKED_OBJECT_REQUEST and
526  * GOT_IMSG_PACKED_RAW_OBJECT_REQUEST data.
527  */
528 struct got_imsg_packed_object {
529 	uint8_t id[SHA1_DIGEST_LENGTH];
530 	int idx;
531 } __attribute__((__packed__));
532 
533 /*
534  * Structure for GOT_IMSG_DELTA data.
535  */
536 struct got_imsg_delta {
537 	/* These fields are the same as in struct got_delta. */
538 	off_t offset;
539 	size_t tslen;
540 	int type;
541 	size_t size;
542 	off_t data_offset;
543 };
544 
545 /*
546  * Structure for GOT_IMSG_RAW_DELTA_REQUEST data.
547  */
548 struct got_imsg_raw_delta_request {
549 	uint8_t id[SHA1_DIGEST_LENGTH];
550 	int idx;
551 };
552 
553 /*
554  * Structure for GOT_IMSG_OBJ_ID_LIST data.
555  * Multiple such messages may be sent back-to-back, where each message
556  * contains a chunk of IDs. The entire list must be terminated with a
557  * GOT_IMSG_OBJ_ID_LIST_DONE message.
558  */
559 struct got_imsg_object_idlist {
560 	size_t nids;
561 
562 	/*
563 	 * Followed by nids * struct got_object_id.
564 	 */
565 
566 #define GOT_IMSG_OBJ_ID_LIST_MAX_NIDS \
567 	((MAX_IMSGSIZE - IMSG_HEADER_SIZE - \
568 	sizeof(struct got_imsg_object_idlist)) / sizeof(struct got_object_id))
569 };
570 
571 /* Structure for GOT_IMSG_COMMIT_TRAVERSAL_REQUEST  */
572 struct got_imsg_commit_traversal_request {
573 	uint8_t id[SHA1_DIGEST_LENGTH];
574 	int idx;
575 	size_t path_len;
576 	/* Followed by path_len bytes of path data */
577 } __attribute__((__packed__));
578 
579 /* Structure for GOT_IMSG_TRAVERSED_COMMITS  */
580 struct got_imsg_traversed_commits {
581 	size_t ncommits;
582 	/* Followed by ncommit IDs of SHA1_DIGEST_LENGTH each */
583 } __attribute__((__packed__));
584 
585 /* Structure for GOT_IMSG_ENUMERATED_COMMIT  */
586 struct got_imsg_enumerated_commit {
587 	uint8_t id[SHA1_DIGEST_LENGTH];
588 	time_t mtime;
589 } __attribute__((__packed__));
590 
591 /* Structure for GOT_IMSG_ENUMERATED_TREE */
592 struct got_imsg_enumerated_tree {
593 	uint8_t id[SHA1_DIGEST_LENGTH]; /* tree ID */
594 	int nentries;			/* number of tree entries */
595 
596 	/* Followed by tree's path in remaining data of imsg buffer. */
597 
598 	/* Followed by nentries * GOT_IMSG_TREE_ENTRY messages. */
599 } __attribute__((__packed__));
600 
601 /*
602  * Structure for GOT_IMSG_GOTCONFIG_REMOTE and
603  * GOT_IMSG_GOTCONFIG_REMOTE data.
604  */
605 struct got_imsg_remote {
606 	size_t name_len;
607 	size_t fetch_url_len;
608 	size_t send_url_len;
609 	int mirror_references;
610 	int fetch_all_branches;
611 	int nfetch_branches;
612 	int nsend_branches;
613 	int nfetch_refs;
614 
615 	/* Followed by name_len data bytes. */
616 	/* Followed by fetch_url_len + send_url_len data bytes. */
617 	/* Followed by nfetch_branches GOT_IMSG_GITCONFIG_STR_VAL messages. */
618 	/* Followed by nsend_branches GOT_IMSG_GITCONFIG_STR_VAL messages. */
619 	/* Followed by nfetch_refs GOT_IMSG_GITCONFIG_STR_VAL messages. */
620 } __attribute__((__packed__));
621 
622 /*
623  * Structure for GOT_IMSG_GITCONFIG_REMOTES data.
624  */
625 struct got_imsg_remotes {
626 	int nremotes; /* This many GOT_IMSG_GITCONFIG_REMOTE messages follow. */
627 };
628 
629 /*
630  * Structure for GOT_IMSG_PATCH data.
631  */
632 struct got_imsg_patch {
633 	int	git;
634 	int	xbit;
635 	char	old[PATH_MAX];
636 	char	new[PATH_MAX];
637 	char	cid[41];
638 	char	blob[41];
639 };
640 
641 /*
642  * Structure for GOT_IMSG_PATCH_HUNK data.
643  */
644 struct got_imsg_patch_hunk {
645 	int	oldfrom;
646 	int	oldlines;
647 	int	newfrom;
648 	int	newlines;
649 };
650 
651 struct got_remote_repo;
652 struct got_pack;
653 struct got_packidx;
654 struct got_pathlist_head;
655 
656 const struct got_error *got_send_ack(pid_t);
657 const struct got_error *got_privsep_wait_for_child(pid_t);
658 const struct got_error *got_privsep_flush_imsg(struct imsgbuf *);
659 const struct got_error *got_privsep_send_stop(int);
660 const struct got_error *got_privsep_recv_imsg(struct imsg *, struct imsgbuf *,
661     size_t);
662 void got_privsep_send_error(struct imsgbuf *, const struct got_error *);
663 const struct got_error *got_privsep_send_ack(struct imsgbuf *);
664 const struct got_error *got_privsep_wait_ack(struct imsgbuf *);
665 const struct got_error *got_privsep_send_obj_req(struct imsgbuf *, int,
666     struct got_object_id *);
667 const struct got_error *got_privsep_send_raw_obj_req(struct imsgbuf *, int,
668     struct got_object_id *);
669 const struct got_error *got_privsep_send_raw_obj_outfd(struct imsgbuf *, int);
670 const struct got_error *got_privsep_send_commit_req(struct imsgbuf *, int,
671     struct got_object_id *, int);
672 const struct got_error *got_privsep_send_tree_req(struct imsgbuf *, int,
673     struct got_object_id *, int);
674 const struct got_error *got_privsep_send_tag_req(struct imsgbuf *, int,
675     struct got_object_id *, int);
676 const struct got_error *got_privsep_send_blob_req(struct imsgbuf *, int,
677     struct got_object_id *, int);
678 const struct got_error *got_privsep_send_blob_outfd(struct imsgbuf *, int);
679 const struct got_error *got_privsep_send_tmpfd(struct imsgbuf *, int);
680 const struct got_error *got_privsep_send_obj(struct imsgbuf *,
681     struct got_object *);
682 const struct got_error *got_privsep_send_index_pack_req(struct imsgbuf *,
683     uint8_t *, int);
684 const struct got_error *got_privsep_send_index_pack_outfd(struct imsgbuf *,
685     int);
686 const struct got_error *got_privsep_recv_index_progress(int *, int *, int *,
687     int *, int *, struct imsgbuf *ibuf);
688 const struct got_error *got_privsep_send_fetch_req(struct imsgbuf *, int,
689     struct got_pathlist_head *, int, struct got_pathlist_head *,
690     struct got_pathlist_head *, int, int);
691 const struct got_error *got_privsep_send_fetch_outfd(struct imsgbuf *, int);
692 const struct got_error *got_privsep_recv_fetch_progress(int *,
693     struct got_object_id **, char **, struct got_pathlist_head *, char **,
694     off_t *, uint8_t *, struct imsgbuf *);
695 const struct got_error *got_privsep_send_send_req(struct imsgbuf *, int,
696     struct got_pathlist_head *, struct got_pathlist_head *, int);
697 const struct got_error *got_privsep_recv_send_remote_refs(
698     struct got_pathlist_head *, struct imsgbuf *);
699 const struct got_error *got_privsep_send_packfd(struct imsgbuf *, int);
700 const struct got_error *got_privsep_recv_send_progress(int *, off_t *,
701     int *, char **, char **, struct imsgbuf *);
702 const struct got_error *got_privsep_get_imsg_obj(struct got_object **,
703     struct imsg *, struct imsgbuf *);
704 const struct got_error *got_privsep_recv_obj(struct got_object **,
705     struct imsgbuf *);
706 const struct got_error *got_privsep_send_raw_obj(struct imsgbuf *, off_t,
707     size_t, uint8_t *);
708 const struct got_error *got_privsep_recv_raw_obj(uint8_t **, off_t *, size_t *,
709     struct imsgbuf *);
710 const struct got_error *got_privsep_send_commit(struct imsgbuf *,
711     struct got_commit_object *);
712 const struct got_error *got_privsep_recv_commit(struct got_commit_object **,
713     struct imsgbuf *);
714 const struct got_error *got_privsep_recv_tree(struct got_tree_object **,
715     struct imsgbuf *);
716 struct got_parsed_tree_entry;
717 const struct got_error *got_privsep_send_tree(struct imsgbuf *,
718     struct got_parsed_tree_entry *, int);
719 const struct got_error *got_privsep_send_blob(struct imsgbuf *, size_t, size_t,
720     const uint8_t *);
721 const struct got_error *got_privsep_recv_blob(uint8_t **, size_t *, size_t *,
722     struct imsgbuf *);
723 const struct got_error *got_privsep_send_tag(struct imsgbuf *,
724     struct got_tag_object *);
725 const struct got_error *got_privsep_recv_tag(struct got_tag_object **,
726     struct imsgbuf *);
727 const struct got_error *got_privsep_init_pack_child(struct imsgbuf *,
728     struct got_pack *, struct got_packidx *);
729 const struct got_error *got_privsep_send_packed_obj_req(struct imsgbuf *, int,
730     struct got_object_id *);
731 const struct got_error *got_privsep_send_packed_raw_obj_req(struct imsgbuf *,
732     int, struct got_object_id *);
733 const struct got_error *got_privsep_send_pack_child_ready(struct imsgbuf *);
734 
735 const struct got_error *got_privsep_send_gitconfig_parse_req(struct imsgbuf *,
736     int);
737 const struct got_error *
738     got_privsep_send_gitconfig_repository_format_version_req(struct imsgbuf *);
739 const struct got_error *got_privsep_send_gitconfig_repository_extensions_req(
740     struct imsgbuf *);
741 const struct got_error *got_privsep_send_gitconfig_author_name_req(
742     struct imsgbuf *);
743 const struct got_error *got_privsep_send_gitconfig_author_email_req(
744     struct imsgbuf *);
745 const struct got_error *got_privsep_send_gitconfig_remotes_req(
746     struct imsgbuf *);
747 const struct got_error *got_privsep_send_gitconfig_owner_req(struct imsgbuf *);
748 const struct got_error *got_privsep_recv_gitconfig_str(char **,
749     struct imsgbuf *);
750 const struct got_error *got_privsep_recv_gitconfig_int(int *, struct imsgbuf *);
751 const struct got_error *got_privsep_recv_gitconfig_remotes(
752     struct got_remote_repo **, int *, struct imsgbuf *);
753 
754 const struct got_error *got_privsep_send_gotconfig_parse_req(struct imsgbuf *,
755     int);
756 const struct got_error *got_privsep_send_gotconfig_author_req(struct imsgbuf *);
757 const struct got_error *got_privsep_send_gotconfig_allowed_signers_req(
758     struct imsgbuf *);
759 const struct got_error *got_privsep_send_gotconfig_revoked_signers_req(
760     struct imsgbuf *);
761 const struct got_error *got_privsep_send_gotconfig_signer_id_req(
762     struct imsgbuf *);
763 const struct got_error *got_privsep_send_gotconfig_remotes_req(
764     struct imsgbuf *);
765 const struct got_error *got_privsep_recv_gotconfig_str(char **,
766     struct imsgbuf *);
767 const struct got_error *got_privsep_recv_gotconfig_remotes(
768     struct got_remote_repo **, int *, struct imsgbuf *);
769 
770 const struct got_error *got_privsep_send_commit_traversal_request(
771     struct imsgbuf *, struct got_object_id *, int, const char *);
772 const struct got_error *got_privsep_recv_traversed_commits(
773     struct got_commit_object **, struct got_object_id **,
774     struct got_object_id_queue *, struct imsgbuf *);
775 const struct got_error *got_privsep_send_enumerated_tree(size_t *,
776     struct imsgbuf *, struct got_object_id *, const char *,
777     struct got_parsed_tree_entry *, int);
778 const struct got_error *got_privsep_send_object_enumeration_request(
779     struct imsgbuf *);
780 const struct got_error *got_privsep_send_object_enumeration_done(
781     struct imsgbuf *);
782 const struct got_error *got_privsep_send_object_enumeration_incomplete(
783     struct imsgbuf *);
784 const struct got_error *got_privsep_send_enumerated_commit(struct imsgbuf *,
785     struct got_object_id *, time_t);
786 const struct got_error *got_privsep_recv_enumerated_objects(int *,
787     struct imsgbuf *, got_object_enumerate_commit_cb,
788     got_object_enumerate_tree_cb, void *, struct got_repository *);
789 
790 const struct got_error *got_privsep_send_raw_delta_req(struct imsgbuf *, int,
791     struct got_object_id *);
792 const struct got_error *got_privsep_send_raw_delta_outfd(struct imsgbuf *, int);
793 const struct got_error *got_privsep_send_raw_delta(struct imsgbuf *, uint64_t,
794     uint64_t,  off_t, off_t, off_t, off_t, struct got_object_id *);
795 const struct got_error *got_privsep_recv_raw_delta(uint64_t *, uint64_t *,
796     off_t *, off_t *, off_t *, off_t *, struct got_object_id **,
797     struct imsgbuf *);
798 
799 const struct got_error *got_privsep_send_object_idlist(struct imsgbuf *,
800     struct got_object_id **, size_t);
801 const struct got_error *got_privsep_send_object_idlist_done(struct imsgbuf *);
802 const struct got_error *got_privsep_recv_object_idlist(int *,
803     struct got_object_id **, size_t *, struct imsgbuf *);
804 
805 const struct got_error *got_privsep_send_delta_reuse_req(struct imsgbuf *);
806 const struct got_error *got_privsep_send_reused_deltas(struct imsgbuf *,
807     struct got_imsg_reused_delta *, size_t);
808 const struct got_error *got_privsep_send_reused_deltas_done(struct imsgbuf *);
809 const struct got_error *got_privsep_recv_reused_deltas(int *,
810     struct got_imsg_reused_delta *, size_t *, struct imsgbuf *);
811 
812 const struct got_error *got_privsep_init_commit_painting(struct imsgbuf *);
813 const struct got_error *got_privsep_send_painting_request(struct imsgbuf *,
814     int, struct got_object_id *, intptr_t);
815 typedef const struct got_error *(*got_privsep_recv_painted_commit_cb)(void *,
816     struct got_object_id *, intptr_t);
817 const struct got_error *got_privsep_send_painted_commits(struct imsgbuf *,
818     struct got_object_id_queue *, int *, int, int);
819 const struct got_error *got_privsep_send_painting_commits_done(struct imsgbuf *);
820 const struct got_error *got_privsep_recv_painted_commits(
821     struct got_object_id_queue *, got_privsep_recv_painted_commit_cb, void *,
822     struct imsgbuf *);
823 
824 void got_privsep_exec_child(int[2], const char *, const char *);