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 struct got_privsep_child {
82 	int imsg_fd;
83 	pid_t pid;
84 	struct imsgbuf *ibuf;
85 };
86 
87 enum got_imsg_type {
88 	/* An error occured while processing a request. */
89 	GOT_IMSG_ERROR,
90 
91 	/* Stop the child process. */
92 	GOT_IMSG_STOP,
93 
94 	/*
95 	 * Messages concerned with read access to objects in a repository.
96 	 * Object and pack files are opened by the main process, where
97 	 * data may be read as a byte string but without any interpretation.
98 	 * Decompression and parsing of object and pack files occurs in a
99 	 * separate process which runs under pledge("stdio recvfd").
100 	 * This sandboxes our own repository parsing code, as well as zlib.
101 	 */
102 	GOT_IMSG_OBJECT_REQUEST,
103 	GOT_IMSG_OBJECT,
104 	GOT_IMSG_COMMIT_REQUEST,
105 	GOT_IMSG_COMMIT,
106 	GOT_IMSG_COMMIT_LOGMSG,
107 	GOT_IMSG_TREE_REQUEST,
108 	GOT_IMSG_TREE,
109 	GOT_IMSG_TREE_ENTRIES,
110 	GOT_IMSG_BLOB_REQUEST,
111 	GOT_IMSG_BLOB_OUTFD,
112 	GOT_IMSG_BLOB,
113 	GOT_IMSG_TAG_REQUEST,
114 	GOT_IMSG_TAG,
115 	GOT_IMSG_TAG_TAGMSG,
116 
117 	/* Messages related to networking. */
118 	GOT_IMSG_FETCH_REQUEST,
119 	GOT_IMSG_FETCH_HAVE_REF,
120 	GOT_IMSG_FETCH_WANTED_BRANCH,
121 	GOT_IMSG_FETCH_WANTED_REF,
122 	GOT_IMSG_FETCH_OUTFD,
123 	GOT_IMSG_FETCH_SYMREFS,
124 	GOT_IMSG_FETCH_REF,
125 	GOT_IMSG_FETCH_SERVER_PROGRESS,
126 	GOT_IMSG_FETCH_DOWNLOAD_PROGRESS,
127 	GOT_IMSG_FETCH_DONE,
128 	GOT_IMSG_IDXPACK_REQUEST,
129 	GOT_IMSG_IDXPACK_OUTFD,
130 	GOT_IMSG_IDXPACK_PROGRESS,
131 	GOT_IMSG_IDXPACK_DONE,
132 	GOT_IMSG_SEND_REQUEST,
133 	GOT_IMSG_SEND_REF,
134 	GOT_IMSG_SEND_REMOTE_REF,
135 	GOT_IMSG_SEND_REF_STATUS,
136 	GOT_IMSG_SEND_PACK_REQUEST,
137 	GOT_IMSG_SEND_PACKFD,
138 	GOT_IMSG_SEND_UPLOAD_PROGRESS,
139 	GOT_IMSG_SEND_DONE,
140 
141 	/* Messages related to pack files. */
142 	GOT_IMSG_PACKIDX,
143 	GOT_IMSG_PACK,
144 	GOT_IMSG_PACKED_OBJECT_REQUEST,
145 	GOT_IMSG_COMMIT_TRAVERSAL_REQUEST,
146 	GOT_IMSG_TRAVERSED_COMMITS,
147 	GOT_IMSG_COMMIT_TRAVERSAL_DONE,
148 	GOT_IMSG_OBJECT_ENUMERATION_REQUEST,
149 	GOT_IMSG_ENUMERATED_COMMIT,
150 	GOT_IMSG_ENUMERATED_TREE,
151 	GOT_IMSG_TREE_ENUMERATION_DONE,
152 	GOT_IMSG_OBJECT_ENUMERATION_DONE,
153 
154 	/* Message sending file descriptor to a temporary file. */
155 	GOT_IMSG_TMPFD,
156 
157 	/* Messages related to gitconfig files. */
158 	GOT_IMSG_GITCONFIG_PARSE_REQUEST,
159 	GOT_IMSG_GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST,
160 	GOT_IMSG_GITCONFIG_REPOSITORY_EXTENSIONS_REQUEST,
161 	GOT_IMSG_GITCONFIG_AUTHOR_NAME_REQUEST,
162 	GOT_IMSG_GITCONFIG_AUTHOR_EMAIL_REQUEST,
163 	GOT_IMSG_GITCONFIG_REMOTES_REQUEST,
164 	GOT_IMSG_GITCONFIG_INT_VAL,
165 	GOT_IMSG_GITCONFIG_STR_VAL,
166 	GOT_IMSG_GITCONFIG_REMOTES,
167 	GOT_IMSG_GITCONFIG_REMOTE,
168 	GOT_IMSG_GITCONFIG_OWNER_REQUEST,
169 	GOT_IMSG_GITCONFIG_OWNER,
170 
171 	/* Messages related to gotconfig files. */
172 	GOT_IMSG_GOTCONFIG_PARSE_REQUEST,
173 	GOT_IMSG_GOTCONFIG_AUTHOR_REQUEST,
174 	GOT_IMSG_GOTCONFIG_REMOTES_REQUEST,
175 	GOT_IMSG_GOTCONFIG_INT_VAL,
176 	GOT_IMSG_GOTCONFIG_STR_VAL,
177 	GOT_IMSG_GOTCONFIG_REMOTES,
178 	GOT_IMSG_GOTCONFIG_REMOTE,
179 
180 	/* Raw object access. Uncompress object data but do not parse it. */
181 	GOT_IMSG_RAW_OBJECT_REQUEST,
182 	GOT_IMSG_RAW_OBJECT_OUTFD,
183 	GOT_IMSG_PACKED_RAW_OBJECT_REQUEST,
184 	GOT_IMSG_RAW_OBJECT,
185 
186 	/* Read raw delta data from pack files. */
187 	GOT_IMSG_RAW_DELTA_OUTFD,
188 	GOT_IMSG_RAW_DELTA_REQUEST,
189 	GOT_IMSG_RAW_DELTA,
190 
191 	/* Re-use deltas found in a pack file. */
192 	GOT_IMSG_DELTA_REUSE_REQUEST,
193 	GOT_IMSG_REUSED_DELTAS,
194 	GOT_IMSG_DELTA_REUSE_DONE,
195 
196 	/* Transfer a list of object IDs. */
197 	GOT_IMSG_OBJ_ID_LIST,
198 	GOT_IMSG_OBJ_ID_LIST_DONE,
199 
200 	/* Messages related to patch files. */
201 	GOT_IMSG_PATCH_FILE,
202 	GOT_IMSG_PATCH_HUNK,
203 	GOT_IMSG_PATCH_DONE,
204 	GOT_IMSG_PATCH_LINE,
205 	GOT_IMSG_PATCH,
206 	GOT_IMSG_PATCH_EOF,
207 };
208 
209 /* Structure for GOT_IMSG_ERROR. */
210 struct got_imsg_error {
211 	int code; /* an error code from got_error.h */
212 	int errno_code; /* in case code equals GOT_ERR_ERRNO */
213 } __attribute__((__packed__));
214 
215 /*
216  * Structure for GOT_IMSG_TREE_REQUEST and GOT_IMSG_OBJECT data.
217  */
218 struct got_imsg_object {
219 	uint8_t id[SHA1_DIGEST_LENGTH];
220 
221 	/* These fields are the same as in struct got_object. */
222 	int type;
223 	int flags;
224 	size_t hdrlen;
225 	size_t size;
226 	off_t pack_offset;
227 	int pack_idx;
228 }  __attribute__((__packed__));
229 
230 /* Structure for GOT_IMSG_COMMIT data. */
231 struct got_imsg_commit_object {
232 	uint8_t tree_id[SHA1_DIGEST_LENGTH];
233 	size_t author_len;
234 	time_t author_time;
235 	time_t author_gmtoff;
236 	size_t committer_len;
237 	time_t committer_time;
238 	time_t committer_gmtoff;
239 	size_t logmsg_len;
240 	int nparents;
241 
242 	/*
243 	 * Followed by author_len + committer_len data bytes
244 	 */
245 
246 	/* Followed by 'nparents' SHA1_DIGEST_LENGTH length strings */
247 
248 	/*
249 	 * Followed by 'logmsg_len' bytes of commit log message data in
250 	 * one or more GOT_IMSG_COMMIT_LOGMSG messages.
251 	 */
252 } __attribute__((__packed__));
253 
254 struct got_imsg_tree_entry {
255 	char id[SHA1_DIGEST_LENGTH];
256 	mode_t mode;
257 	size_t namelen;
258 	/* Followed by namelen bytes of entry's name, not NUL-terminated. */
259 } __attribute__((__packed__));
260 
261 /* Structure for GOT_IMSG_TREE_ENTRIES. */
262 struct got_imsg_tree_entries {
263 	size_t nentries; /* Number of tree entries contained in this message. */
264 
265 	/* Followed by nentries * struct got_imsg_tree_entry */
266 };
267 
268 /* Structure for GOT_IMSG_TREE_OBJECT_REPLY data. */
269 struct got_imsg_tree_object {
270 	int nentries; /* This many tree entries follow. */
271 };
272 
273 /* Structure for GOT_IMSG_BLOB. */
274 struct got_imsg_blob {
275 	size_t size;
276 	size_t hdrlen;
277 
278 	/*
279 	 * If size <= GOT_PRIVSEP_INLINE_BLOB_DATA_MAX, blob data follows
280 	 * in the imsg buffer. Otherwise, blob data has been written to a
281 	 * file descriptor passed via the GOT_IMSG_BLOB_OUTFD imsg.
282 	 */
283 #define GOT_PRIVSEP_INLINE_BLOB_DATA_MAX \
284 	(MAX_IMSGSIZE - IMSG_HEADER_SIZE - sizeof(struct got_imsg_blob))
285 };
286 
287 /* Structure for GOT_IMSG_RAW_OBJECT. */
288 struct got_imsg_raw_obj {
289 	off_t size;
290 	size_t hdrlen;
291 
292 	/*
293 	 * If size <= GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX, object data follows
294 	 * in the imsg buffer. Otherwise, object data has been written to a
295 	 * file descriptor passed via the GOT_IMSG_RAW_OBJECT_OUTFD imsg.
296 	 */
297 #define GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX \
298 	(MAX_IMSGSIZE - IMSG_HEADER_SIZE - sizeof(struct got_imsg_raw_obj))
299 };
300 
301 /* Structure for GOT_IMSG_RAW_DELTA. */
302 struct got_imsg_raw_delta {
303 	uint8_t base_id[SHA1_DIGEST_LENGTH];
304 	uint64_t base_size;
305 	uint64_t result_size;
306 	off_t delta_size;
307 	off_t delta_compressed_size;
308 	off_t delta_offset;
309 	off_t delta_out_offset;
310 
311 	/*
312 	 * Delta data has been written at delta_out_offset to the file
313 	 * descriptor passed via the GOT_IMSG_RAW_DELTA_OUTFD imsg.
314 	 */
315 };
316 
317 /* Structures for GOT_IMSG_REUSED_DELTAS. */
318 struct got_imsg_reused_delta {
319 	struct got_object_id id;
320 	struct got_object_id base_id;
321 	uint64_t base_size;
322 	uint64_t result_size;
323 	off_t delta_size;
324 	off_t delta_compressed_size;
325 	off_t delta_offset;
326 	off_t delta_out_offset;
327 
328 	/*
329 	 * Delta data has been written at delta_out_offset to the file
330 	 * descriptor passed via the GOT_IMSG_RAW_DELTA_OUTFD imsg.
331 	 */
332 };
333 struct got_imsg_reused_deltas {
334 	size_t ndeltas;
335 
336 	/*
337 	 * Followed by ndeltas * struct got_imsg_reused_delta.
338 	 */
339 
340 #define GOT_IMSG_REUSED_DELTAS_MAX_NDELTAS \
341 	((MAX_IMSGSIZE - IMSG_HEADER_SIZE - \
342 	sizeof(struct got_imsg_reused_deltas)) \
343 	/ sizeof(struct got_imsg_reused_delta))
344 };
345 
346 /* Structure for GOT_IMSG_TAG data. */
347 struct got_imsg_tag_object {
348 	uint8_t id[SHA1_DIGEST_LENGTH];
349 	int obj_type;
350 	size_t tag_len;
351 	size_t tagger_len;
352 	time_t tagger_time;
353 	time_t tagger_gmtoff;
354 	size_t tagmsg_len;
355 
356 	/*
357 	 * Followed by tag_len + tagger_len data bytes
358 	 */
359 
360 	/*
361 	 * Followed by 'tagmsg_len' bytes of tag message data in
362 	 * one or more GOT_IMSG_TAG_TAGMSG messages.
363 	 */
364 } __attribute__((__packed__));
365 
366 /* Structure for GOT_IMSG_FETCH_HAVE_REF data. */
367 struct got_imsg_fetch_have_ref {
368 	uint8_t id[SHA1_DIGEST_LENGTH];
369 	size_t name_len;
370 	/* Followed by name_len data bytes. */
371 } __attribute__((__packed__));
372 
373 /* Structure for GOT_IMSG_FETCH_WANTED_BRANCH data. */
374 struct got_imsg_fetch_wanted_branch {
375 	size_t name_len;
376 	/* Followed by name_len data bytes. */
377 } __attribute__((__packed__));
378 
379 /* Structure for GOT_IMSG_FETCH_WANTED_REF data. */
380 struct got_imsg_fetch_wanted_ref {
381 	size_t name_len;
382 	/* Followed by name_len data bytes. */
383 } __attribute__((__packed__));
384 
385 /* Structure for GOT_IMSG_FETCH_REQUEST data. */
386 struct got_imsg_fetch_request {
387 	int fetch_all_branches;
388 	int list_refs_only;
389 	int verbosity;
390 	size_t n_have_refs;
391 	size_t n_wanted_branches;
392 	size_t n_wanted_refs;
393 	/* Followed by n_have_refs GOT_IMSG_FETCH_HAVE_REF messages. */
394 	/* Followed by n_wanted_branches times GOT_IMSG_FETCH_WANTED_BRANCH. */
395 	/* Followed by n_wanted_refs times GOT_IMSG_FETCH_WANTED_REF. */
396 } __attribute__((__packed__));
397 
398 /* Structures for GOT_IMSG_FETCH_SYMREFS data. */
399 struct got_imsg_fetch_symref {
400 	size_t name_len;
401 	size_t target_len;
402 
403 	/*
404 	 * Followed by name_len + target_len data bytes.
405 	 */
406 } __attribute__((__packed__));
407 
408 struct got_imsg_fetch_symrefs {
409 	size_t nsymrefs;
410 
411 	/* Followed by nsymrefs times of got_imsg_fetch_symref data. */
412 } __attribute__((__packed__));
413 
414 /* Structure for GOT_IMSG_FETCH_REF data. */
415 struct got_imsg_fetch_ref {
416 	/* Describes a reference which will be fetched. */
417 	uint8_t refid[SHA1_DIGEST_LENGTH];
418 	/* Followed by reference name in remaining data of imsg buffer. */
419 };
420 
421 /* Structure for GOT_IMSG_FETCH_DOWNLOAD_PROGRESS data. */
422 struct got_imsg_fetch_download_progress {
423 	/* Number of packfile data bytes downloaded so far. */
424 	off_t packfile_bytes;
425 };
426 
427 /* Structure for GOT_IMSG_SEND_REQUEST data. */
428 struct got_imsg_send_request {
429 	int verbosity;
430 	size_t nrefs;
431 	/* Followed by nrefs GOT_IMSG_SEND_REF messages. */
432 } __attribute__((__packed__));
433 
434 /* Structure for GOT_IMSG_SEND_UPLOAD_PROGRESS data. */
435 struct got_imsg_send_upload_progress {
436 	/* Number of packfile data bytes uploaded so far. */
437 	off_t packfile_bytes;
438 };
439 
440 /* Structure for GOT_IMSG_SEND_REF data. */
441 struct got_imsg_send_ref {
442 	uint8_t id[SHA1_DIGEST_LENGTH];
443 	int delete;
444 	size_t name_len;
445 	/* Followed by name_len data bytes. */
446 } __attribute__((__packed__));
447 
448 /* Structure for GOT_IMSG_SEND_REMOTE_REF data. */
449 struct got_imsg_send_remote_ref {
450 	uint8_t id[SHA1_DIGEST_LENGTH];
451 	size_t name_len;
452 	/* Followed by name_len data bytes. */
453 } __attribute__((__packed__));
454 
455 /* Structure for GOT_IMSG_SEND_REF_STATUS data. */
456 struct got_imsg_send_ref_status {
457 	int success;
458 	size_t name_len;
459 	/* Followed by name_len data bytes. */
460 } __attribute__((__packed__));
461 
462 /* Structure for GOT_IMSG_IDXPACK_REQUEST data. */
463 struct got_imsg_index_pack_request {
464 	uint8_t pack_hash[SHA1_DIGEST_LENGTH];
465 } __attribute__((__packed__));
466 
467 /* Structure for GOT_IMSG_IDXPACK_PROGRESS data. */
468 struct got_imsg_index_pack_progress {
469 	/* Total number of objects in pack file. */
470 	int nobj_total;
471 
472 	/* Number of objects indexed so far. */
473 	int nobj_indexed;
474 
475 	/* Number of non-deltified objects in pack file. */
476 	int nobj_loose;
477 
478 	/* Number of deltified objects resolved so far. */
479 	int nobj_resolved;
480 };
481 
482 /* Structure for GOT_IMSG_PACKIDX. */
483 struct got_imsg_packidx {
484 	size_t len;
485 	off_t packfile_size;
486 	/* Additionally, a file desciptor is passed via imsg. */
487 };
488 
489 /* Structure for GOT_IMSG_PACK. */
490 struct got_imsg_pack {
491 	char path_packfile[PATH_MAX];
492 	size_t filesize;
493 	/* Additionally, a file desciptor is passed via imsg. */
494 } __attribute__((__packed__));
495 
496 /*
497  * Structure for GOT_IMSG_OBJECT_REQUEST, GOT_IMSG_BLOB_REQUEST,
498  * GOT_IMSG_TREE_REQUEST, GOT_IMSG_COMMIT_REQUEST, and
499  * GOT_IMSG_TAG_REQUEST data.
500  */
501 struct got_object_id;
502 
503 /*
504  * Structure for GOT_IMSG_PACKED_OBJECT_REQUEST and
505  * GOT_IMSG_PACKED_RAW_OBJECT_REQUEST data.
506  */
507 struct got_imsg_packed_object {
508 	uint8_t id[SHA1_DIGEST_LENGTH];
509 	int idx;
510 } __attribute__((__packed__));
511 
512 /*
513  * Structure for GOT_IMSG_DELTA data.
514  */
515 struct got_imsg_delta {
516 	/* These fields are the same as in struct got_delta. */
517 	off_t offset;
518 	size_t tslen;
519 	int type;
520 	size_t size;
521 	off_t data_offset;
522 };
523 
524 /*
525  * Structure for GOT_IMSG_RAW_DELTA_REQUEST data.
526  */
527 struct got_imsg_raw_delta_request {
528 	uint8_t id[SHA1_DIGEST_LENGTH];
529 	int idx;
530 };
531 
532 /*
533  * Structure for GOT_IMSG_OBJ_ID_LIST data.
534  * Multiple such messages may be sent back-to-back, where each message
535  * contains a chunk of IDs. The entire list must be terminated with a
536  * GOT_IMSG_OBJ_ID_LIST_DONE message.
537  */
538 struct got_imsg_object_idlist {
539 	size_t nids;
540 
541 	/*
542 	 * Followed by nids * struct got_object_id.
543 	 */
544 
545 #define GOT_IMSG_OBJ_ID_LIST_MAX_NIDS \
546 	((MAX_IMSGSIZE - IMSG_HEADER_SIZE - \
547 	sizeof(struct got_imsg_object_idlist)) / sizeof(struct got_object_id))
548 };
549 
550 /* Structure for GOT_IMSG_COMMIT_TRAVERSAL_REQUEST  */
551 struct got_imsg_commit_traversal_request {
552 	uint8_t id[SHA1_DIGEST_LENGTH];
553 	int idx;
554 	size_t path_len;
555 	/* Followed by path_len bytes of path data */
556 } __attribute__((__packed__));
557 
558 /* Structure for GOT_IMSG_TRAVERSED_COMMITS  */
559 struct got_imsg_traversed_commits {
560 	size_t ncommits;
561 	/* Followed by ncommit IDs of SHA1_DIGEST_LENGTH each */
562 } __attribute__((__packed__));
563 
564 /* Structure for GOT_IMSG_ENUMERATED_COMMIT  */
565 struct got_imsg_enumerated_commit {
566 	uint8_t id[SHA1_DIGEST_LENGTH];
567 	time_t mtime;
568 } __attribute__((__packed__));
569 
570 /* Structure for GOT_IMSG_ENUMERATED_TREE */
571 struct got_imsg_enumerated_tree {
572 	uint8_t id[SHA1_DIGEST_LENGTH]; /* tree ID */
573 	int nentries;			/* number of tree entries */
574 
575 	/* Followed by tree's path in remaining data of imsg buffer. */
576 
577 	/* Followed by nentries * GOT_IMSG_TREE_ENTRY messages. */
578 } __attribute__((__packed__));
579 
580 /*
581  * Structure for GOT_IMSG_GOTCONFIG_REMOTE and
582  * GOT_IMSG_GOTCONFIG_REMOTE data.
583  */
584 struct got_imsg_remote {
585 	size_t name_len;
586 	size_t fetch_url_len;
587 	size_t send_url_len;
588 	int mirror_references;
589 	int fetch_all_branches;
590 	int nfetch_branches;
591 	int nsend_branches;
592 	int nfetch_refs;
593 
594 	/* Followed by name_len data bytes. */
595 	/* Followed by fetch_url_len + send_url_len data bytes. */
596 	/* Followed by nfetch_branches GOT_IMSG_GITCONFIG_STR_VAL messages. */
597 	/* Followed by nsend_branches GOT_IMSG_GITCONFIG_STR_VAL messages. */
598 	/* Followed by nfetch_refs GOT_IMSG_GITCONFIG_STR_VAL messages. */
599 } __attribute__((__packed__));
600 
601 /*
602  * Structure for GOT_IMSG_GITCONFIG_REMOTES data.
603  */
604 struct got_imsg_remotes {
605 	int nremotes; /* This many GOT_IMSG_GITCONFIG_REMOTE messages follow. */
606 };
607 
608 /*
609  * Structure for GOT_IMSG_PATCH data.
610  */
611 struct got_imsg_patch {
612 	int	git;
613 	char	old[PATH_MAX];
614 	char	new[PATH_MAX];
615 };
616 
617 /*
618  * Structure for GOT_IMSG_PATCH_HUNK data.
619  */
620 struct got_imsg_patch_hunk {
621 	int	oldfrom;
622 	int	oldlines;
623 	int	newfrom;
624 	int	newlines;
625 };
626 
627 struct got_remote_repo;
628 struct got_pack;
629 struct got_packidx;
630 struct got_pathlist_head;
631 
632 const struct got_error *got_send_ack(pid_t);
633 const struct got_error *got_privsep_wait_for_child(pid_t);
634 const struct got_error *got_privsep_flush_imsg(struct imsgbuf *);
635 const struct got_error *got_privsep_send_stop(int);
636 const struct got_error *got_privsep_recv_imsg(struct imsg *, struct imsgbuf *,
637     size_t);
638 void got_privsep_send_error(struct imsgbuf *, const struct got_error *);
639 const struct got_error *got_privsep_send_ack(struct imsgbuf *);
640 const struct got_error *got_privsep_wait_ack(struct imsgbuf *);
641 const struct got_error *got_privsep_send_obj_req(struct imsgbuf *, int,
642     struct got_object_id *);
643 const struct got_error *got_privsep_send_raw_obj_req(struct imsgbuf *, int,
644     struct got_object_id *);
645 const struct got_error *got_privsep_send_raw_obj_outfd(struct imsgbuf *, int);
646 const struct got_error *got_privsep_send_commit_req(struct imsgbuf *, int,
647     struct got_object_id *, int);
648 const struct got_error *got_privsep_send_tree_req(struct imsgbuf *, int,
649     struct got_object_id *, int);
650 const struct got_error *got_privsep_send_tag_req(struct imsgbuf *, int,
651     struct got_object_id *, int);
652 const struct got_error *got_privsep_send_blob_req(struct imsgbuf *, int,
653     struct got_object_id *, int);
654 const struct got_error *got_privsep_send_blob_outfd(struct imsgbuf *, int);
655 const struct got_error *got_privsep_send_tmpfd(struct imsgbuf *, int);
656 const struct got_error *got_privsep_send_obj(struct imsgbuf *,
657     struct got_object *);
658 const struct got_error *got_privsep_send_index_pack_req(struct imsgbuf *,
659     uint8_t *, int);
660 const struct got_error *got_privsep_send_index_pack_outfd(struct imsgbuf *,
661     int);
662 const struct got_error *got_privsep_recv_index_progress(int *, int *, int *,
663     int *, int *, struct imsgbuf *ibuf);
664 const struct got_error *got_privsep_send_fetch_req(struct imsgbuf *, int,
665     struct got_pathlist_head *, int, struct got_pathlist_head *,
666     struct got_pathlist_head *, int, int);
667 const struct got_error *got_privsep_send_fetch_outfd(struct imsgbuf *, int);
668 const struct got_error *got_privsep_recv_fetch_progress(int *,
669     struct got_object_id **, char **, struct got_pathlist_head *, char **,
670     off_t *, uint8_t *, struct imsgbuf *);
671 const struct got_error *got_privsep_send_send_req(struct imsgbuf *, int,
672     struct got_pathlist_head *, struct got_pathlist_head *, int);
673 const struct got_error *got_privsep_recv_send_remote_refs(
674     struct got_pathlist_head *, struct imsgbuf *);
675 const struct got_error *got_privsep_send_packfd(struct imsgbuf *, int);
676 const struct got_error *got_privsep_recv_send_progress(int *, off_t *,
677     int *, char **, struct imsgbuf *);
678 const struct got_error *got_privsep_get_imsg_obj(struct got_object **,
679     struct imsg *, struct imsgbuf *);
680 const struct got_error *got_privsep_recv_obj(struct got_object **,
681     struct imsgbuf *);
682 const struct got_error *got_privsep_send_raw_obj(struct imsgbuf *, off_t,
683     size_t, uint8_t *);
684 const struct got_error *got_privsep_recv_raw_obj(uint8_t **, off_t *, size_t *,
685     struct imsgbuf *);
686 const struct got_error *got_privsep_send_commit(struct imsgbuf *,
687     struct got_commit_object *);
688 const struct got_error *got_privsep_recv_commit(struct got_commit_object **,
689     struct imsgbuf *);
690 const struct got_error *got_privsep_recv_tree(struct got_tree_object **,
691     struct imsgbuf *);
692 struct got_parsed_tree_entry;
693 const struct got_error *got_privsep_send_tree(struct imsgbuf *,
694     struct got_parsed_tree_entry *, int);
695 const struct got_error *got_privsep_send_blob(struct imsgbuf *, size_t, size_t,
696     const uint8_t *);
697 const struct got_error *got_privsep_recv_blob(uint8_t **, size_t *, size_t *,
698     struct imsgbuf *);
699 const struct got_error *got_privsep_send_tag(struct imsgbuf *,
700     struct got_tag_object *);
701 const struct got_error *got_privsep_recv_tag(struct got_tag_object **,
702     struct imsgbuf *);
703 const struct got_error *got_privsep_init_pack_child(struct imsgbuf *,
704     struct got_pack *, struct got_packidx *);
705 const struct got_error *got_privsep_send_packed_obj_req(struct imsgbuf *, int,
706     struct got_object_id *);
707 const struct got_error *got_privsep_send_packed_raw_obj_req(struct imsgbuf *,
708     int, struct got_object_id *);
709 const struct got_error *got_privsep_send_pack_child_ready(struct imsgbuf *);
710 
711 const struct got_error *got_privsep_send_gitconfig_parse_req(struct imsgbuf *,
712     int);
713 const struct got_error *
714     got_privsep_send_gitconfig_repository_format_version_req(struct imsgbuf *);
715 const struct got_error *got_privsep_send_gitconfig_repository_extensions_req(
716     struct imsgbuf *);
717 const struct got_error *got_privsep_send_gitconfig_author_name_req(
718     struct imsgbuf *);
719 const struct got_error *got_privsep_send_gitconfig_author_email_req(
720     struct imsgbuf *);
721 const struct got_error *got_privsep_send_gitconfig_remotes_req(
722     struct imsgbuf *);
723 const struct got_error *got_privsep_send_gitconfig_owner_req(struct imsgbuf *);
724 const struct got_error *got_privsep_recv_gitconfig_str(char **,
725     struct imsgbuf *);
726 const struct got_error *got_privsep_recv_gitconfig_int(int *, struct imsgbuf *);
727 const struct got_error *got_privsep_recv_gitconfig_remotes(
728     struct got_remote_repo **, int *, struct imsgbuf *);
729 
730 const struct got_error *got_privsep_send_gotconfig_parse_req(struct imsgbuf *,
731     int);
732 const struct got_error *got_privsep_send_gotconfig_author_req(struct imsgbuf *);
733 const struct got_error *got_privsep_send_gotconfig_remotes_req(
734     struct imsgbuf *);
735 const struct got_error *got_privsep_recv_gotconfig_str(char **,
736     struct imsgbuf *);
737 const struct got_error *got_privsep_recv_gotconfig_remotes(
738     struct got_remote_repo **, int *, struct imsgbuf *);
739 
740 const struct got_error *got_privsep_send_commit_traversal_request(
741     struct imsgbuf *, struct got_object_id *, int, const char *);
742 const struct got_error *got_privsep_recv_traversed_commits(
743     struct got_commit_object **, struct got_object_id **,
744     struct got_object_id_queue *, struct imsgbuf *);
745 const struct got_error *got_privsep_send_enumerated_tree(size_t *,
746     struct imsgbuf *, struct got_object_id *, const char *,
747     struct got_parsed_tree_entry *, int);
748 const struct got_error *got_privsep_send_object_enumeration_request(
749     struct imsgbuf *);
750 const struct got_error *got_privsep_send_object_enumeration_done(
751     struct imsgbuf *);
752 const struct got_error *got_privsep_send_enumerated_commit(struct imsgbuf *,
753     struct got_object_id *, time_t);
754 const struct got_error *got_privsep_recv_enumerated_objects(struct imsgbuf *,
755     got_object_enumerate_commit_cb, got_object_enumerate_tree_cb, void *,
756     struct got_repository *);
757 
758 const struct got_error *got_privsep_send_raw_delta_req(struct imsgbuf *, int,
759     struct got_object_id *);
760 const struct got_error *got_privsep_send_raw_delta_outfd(struct imsgbuf *, int);
761 const struct got_error *got_privsep_send_raw_delta(struct imsgbuf *, uint64_t,
762     uint64_t,  off_t, off_t, off_t, off_t, struct got_object_id *);
763 const struct got_error *got_privsep_recv_raw_delta(uint64_t *, uint64_t *,
764     off_t *, off_t *, off_t *, off_t *, struct got_object_id **,
765     struct imsgbuf *);
766 
767 const struct got_error *got_privsep_send_object_idlist(struct imsgbuf *,
768     struct got_object_id **, size_t);
769 const struct got_error *got_privsep_send_object_idlist_done(struct imsgbuf *);
770 const struct got_error *got_privsep_recv_object_idlist(int *,
771     struct got_object_id **, size_t *, struct imsgbuf *);
772 
773 const struct got_error *got_privsep_send_delta_reuse_req(struct imsgbuf *);
774 const struct got_error *got_privsep_send_reused_deltas(struct imsgbuf *,
775     struct got_imsg_reused_delta *, size_t);
776 const struct got_error *got_privsep_send_reused_deltas_done(struct imsgbuf *);
777 const struct got_error *got_privsep_recv_reused_deltas(int *, 
778     struct got_imsg_reused_delta *, size_t *, struct imsgbuf *);
779 
780 void got_privsep_exec_child(int[2], const char *, const char *);