1 /*
2  * Copyright (c) 2022 Stefan Sperling <stsp@openbsd.org>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 
18 #define GOTD_UNIX_SOCKET "/var/run/gotd.sock"
19 #define GOTD_UNIX_SOCKET_BACKLOG 10
20 #define GOTD_USER	"_gotd"
21 #define GOTD_CONF_PATH	"/etc/gotd.conf"
22 #define GOTD_EMPTY_PATH	"/var/empty"
23 
24 #ifndef GOT_LIBEXECDIR
25 #define GOT_LIBEXECDIR /usr/libexec
26 #endif
27 
28 #define GOTD_STRINGIFY(x) #x
29 #define GOTD_STRINGVAL(x) GOTD_STRINGIFY(x)
30 
31 #define GOTD_PROG_NOTIFY_EMAIL	got-notify-email
32 #define GOTD_PROG_NOTIFY_HTTP	got-notify-http
33 
34 #define GOTD_PATH_PROG_NOTIFY_EMAIL \
35 	GOTD_STRINGVAL(GOT_LIBEXECDIR) "/" \
36 	GOTD_STRINGVAL(GOTD_PROG_NOTIFY_EMAIL)
37 #define GOTD_PATH_PROG_NOTIFY_HTTP \
38 	GOTD_STRINGVAL(GOT_LIBEXECDIR) "/" \
39 	GOTD_STRINGVAL(GOTD_PROG_NOTIFY_HTTP)
40 
41 #define GOTD_MAXCLIENTS		1024
42 #define GOTD_MAX_CONN_PER_UID	4
43 #define GOTD_FD_RESERVE		5
44 #define GOTD_FD_NEEDED		6
45 #define GOTD_FILENO_MSG_PIPE	3
46 
47 #define GOTD_DEFAULT_REQUEST_TIMEOUT	3600
48 
49 /* Client hash tables need some extra room. */
50 #define GOTD_CLIENT_TABLE_SIZE (GOTD_MAXCLIENTS * 4)
51 
52 enum gotd_procid {
53 	PROC_GOTD	= 0,
54 	PROC_LISTEN,
55 	PROC_AUTH,
56 	PROC_SESSION_READ,
57 	PROC_SESSION_WRITE,
58 	PROC_REPO_READ,
59 	PROC_REPO_WRITE,
60 	PROC_GITWRAPPER,
61 	PROC_NOTIFY,
62 	PROC_MAX,
63 };
64 
65 struct gotd_imsgev {
66 	struct imsgbuf	 ibuf;
67 	void		(*handler)(int, short, void *);
68 	void		*handler_arg;
69 	struct event	 ev;
70 	short		 events;
71 };
72 
73 enum gotd_access {
74 	GOTD_ACCESS_PERMITTED = 1,
75 	GOTD_ACCESS_DENIED
76 };
77 
78 struct gotd_access_rule {
79 	STAILQ_ENTRY(gotd_access_rule) entry;
80 
81 	enum gotd_access access;
82 
83 	int authorization;
84 #define GOTD_AUTH_READ		0x1
85 #define GOTD_AUTH_WRITE		0x2
86 
87 	char *identifier;
88 };
89 STAILQ_HEAD(gotd_access_rule_list, gotd_access_rule);
90 
91 enum gotd_notification_target_type {
92 	GOTD_NOTIFICATION_VIA_EMAIL,
93 	GOTD_NOTIFICATION_VIA_HTTP
94 };
95 
96 struct gotd_notification_target {
97 	STAILQ_ENTRY(gotd_notification_target) entry;
98 
99 	enum gotd_notification_target_type type;
100 	union {
101 		struct {
102 			char *sender;
103 			char *recipient;
104 			char *responder;
105 			char *hostname;
106 			char *port;
107 		} email;
108 		struct {
109 			int   tls;
110 			char *hostname;
111 			char *port;
112 			char *path;
113 			char *user;
114 			char *password;
115 		} http;
116 	} conf;
117 };
118 STAILQ_HEAD(gotd_notification_targets, gotd_notification_target);
119 
120 struct gotd_repo {
121 	TAILQ_ENTRY(gotd_repo)	 entry;
122 
123 	char name[NAME_MAX];
124 	char path[PATH_MAX];
125 
126 	struct gotd_access_rule_list rules;
127 	struct got_pathlist_head protected_tag_namespaces;
128 	struct got_pathlist_head protected_branch_namespaces;
129 	struct got_pathlist_head protected_branches;
130 
131 	struct got_pathlist_head notification_refs;
132 	struct got_pathlist_head notification_ref_namespaces;
133 	struct gotd_notification_targets notification_targets;
134 };
135 TAILQ_HEAD(gotd_repolist, gotd_repo);
136 
137 struct gotd_client_capability {
138 	char *key;
139 	char *value;
140 };
141 
142 struct gotd_object_id_array {
143 	struct got_object_id		**ids;
144 	size_t				 nalloc;
145 	size_t				 nids;
146 };
147 
148 struct gotd_uid_connection_limit {
149 	uid_t uid;
150 	int max_connections;
151 };
152 
153 struct gotd_child_proc;
154 
155 struct gotd {
156 	pid_t pid;
157 	char unix_socket_path[PATH_MAX];
158 	char user_name[32];
159 	struct gotd_repolist repos;
160 	int nrepos;
161 	struct gotd_child_proc *listen_proc;
162 	struct gotd_child_proc *notify_proc;
163 	int notifications_enabled;
164 	struct timeval request_timeout;
165 	struct timeval auth_timeout;
166 	struct gotd_uid_connection_limit *connection_limits;
167 	size_t nconnection_limits;
168 
169 	char *argv0;
170 	const char *confpath;
171 	int daemonize;
172 	int verbosity;
173 };
174 
175 enum gotd_imsg_type {
176 	/* An error occured while processing a request. */
177 	GOTD_IMSG_ERROR,
178 
179 	/* Commands used by gotctl(8). */
180 	GOTD_IMSG_INFO,
181 	GOTD_IMSG_INFO_REPO,
182 	GOTD_IMSG_INFO_CLIENT,
183 	GOTD_IMSG_STOP,
184 
185 	/* Request a list of references. */
186 	GOTD_IMSG_LIST_REFS,
187 	GOTD_IMSG_LIST_REFS_INTERNAL,
188 
189 	/* References. */
190 	GOTD_IMSG_REFLIST,
191 	GOTD_IMSG_REF,
192 	GOTD_IMSG_SYMREF,
193 
194 	/* Git protocol capabilities. */
195 	GOTD_IMSG_CAPABILITIES,
196 	GOTD_IMSG_CAPABILITY,
197 
198 	/* Git protocol chatter. */
199 	GOTD_IMSG_WANT,		/* The client wants an object. */
200 	GOTD_IMSG_HAVE,		/* The client has an object. */
201 	GOTD_IMSG_ACK,		/* The server has an object or a reference. */
202 	GOTD_IMSG_NAK,		/* The server does not have an object/ref. */
203 	GOTD_IMSG_REF_UPDATE,	/* The client wants to update a reference. */
204 	GOTD_IMSG_REF_DELETE,	/* The client wants to delete a reference. */
205 	GOTD_IMSG_FLUSH,	/* The client sent a flush packet. */
206 	GOTD_IMSG_DONE,		/* The client is done chatting. */
207 
208 	/* Sending or receiving a pack file. */
209 	GOTD_IMSG_SEND_PACKFILE, /* The server is sending a pack file. */
210 	GOTD_IMSG_RECV_PACKFILE, /* The server is receiving a pack file. */
211 	GOTD_IMSG_PACKIDX_FILE,  /* Temporary file handle for new pack index. */
212 	GOTD_IMSG_PACKFILE_PIPE, /* Pipe to send/receive a pack file stream. */
213 	GOTD_IMSG_PACKFILE_PROGRESS, /* Progress reporting. */
214 	GOTD_IMSG_PACKFILE_READY, /* Pack file is ready to be sent. */
215 	GOTD_IMSG_PACKFILE_STATUS, /* Received pack success/failure status. */
216 	GOTD_IMSG_PACKFILE_INSTALL, /* Received pack file can be installed. */
217 	GOTD_IMSG_PACKFILE_DONE, /* Pack file has been sent/received. */
218 
219 	/* Reference updates. */
220 	GOTD_IMSG_REF_UPDATES_START, /* Ref updates starting. */
221 	GOTD_IMSG_REF_UPDATE_OK, /* Update went OK. */
222 	GOTD_IMSG_REF_UPDATE_NG, /* Update was not good. */
223 	GOTD_IMSG_REFS_UPDATED, /* The server proccessed all ref updates. */
224 
225 	/* Client connections. */
226 	GOTD_IMSG_DISCONNECT,
227 	GOTD_IMSG_CONNECT,
228 
229 	/* Child process management. */
230 	GOTD_IMSG_CLIENT_SESSION_READY,
231 	GOTD_IMSG_REPO_CHILD_READY,
232 	GOTD_IMSG_CONNECT_REPO_CHILD,
233 
234 	/* Auth child process. */
235 	GOTD_IMSG_AUTHENTICATE,
236 	GOTD_IMSG_ACCESS_GRANTED,
237 
238 	/* Notify child process. */
239 	GOTD_IMSG_CONNECT_NOTIFIER,
240 	GOTD_IMSG_CONNECT_SESSION,
241 	GOTD_IMSG_NOTIFY,
242 	GOTD_IMSG_NOTIFICATION_SENT
243 };
244 
245 /* Structure for GOTD_IMSG_ERROR. */
246 struct gotd_imsg_error {
247 	int code; /* an error code from got_error.h */
248 	int errno_code; /* in case code equals GOT_ERR_ERRNO */
249 	uint32_t client_id;
250 	char msg[GOT_ERR_MAX_MSG_SIZE];
251 } __attribute__((__packed__));
252 
253 /* Structure for GOTD_IMSG_INFO. */
254 struct gotd_imsg_info {
255 	pid_t pid;
256 	int verbosity;
257 	int nrepos;
258 	int nclients;
259 
260 	/* Followed by nrepos GOTD_IMSG_INFO_REPO messages. */
261 	/* Followed by nclients GOTD_IMSG_INFO_CLIENT messages. */
262 };
263 
264 /* Structure for GOTD_IMSG_INFO_REPO. */
265 struct gotd_imsg_info_repo {
266 	char repo_name[NAME_MAX];
267 	char repo_path[PATH_MAX];
268 };
269 
270 /* Structure for GOTD_IMSG_INFO_CLIENT */
271 struct gotd_imsg_info_client {
272 	uid_t euid;
273 	gid_t egid;
274 	char repo_name[NAME_MAX];
275 	int is_writing;
276 	pid_t session_child_pid;
277 	pid_t repo_child_pid;
278 };
279 
280 /* Structure for GOTD_IMSG_LIST_REFS. */
281 struct gotd_imsg_list_refs {
282 	char repo_name[NAME_MAX];
283 	int client_is_reading; /* 1 if reading, 0 if writing */
284 };
285 
286 /* Structure for GOTD_IMSG_REFLIST. */
287 struct gotd_imsg_reflist {
288 	size_t nrefs;
289 
290 	/* Followed by nrefs times of gotd_imsg_ref/gotd_imsg_symref data. */
291 } __attribute__((__packed__));
292 
293 /* Structure for GOTD_IMSG_REF data. */
294 struct gotd_imsg_ref {
295 	uint8_t id[SHA1_DIGEST_LENGTH];
296 	size_t name_len;
297 	/* Followed by name_len data bytes. */
298 } __attribute__((__packed__));
299 
300 /* Structure for GOTD_IMSG_SYMREF data. */
301 struct gotd_imsg_symref {
302 	size_t name_len;
303 	size_t target_len;
304 	uint8_t target_id[SHA1_DIGEST_LENGTH];
305 
306 	/*
307 	 * Followed by name_len + target_len data bytes.
308 	 */
309 } __attribute__((__packed__));
310 
311 /* Structure for GOTD_IMSG_CAPABILITIES data. */
312 struct gotd_imsg_capabilities {
313 	size_t ncapabilities;
314 
315 	/*
316 	 * Followed by ncapabilities * GOTD_IMSG_CAPABILITY.
317 	 */
318 } __attribute__((__packed__));
319 
320 /* Structure for GOTD_IMSG_CAPABILITY data. */
321 struct gotd_imsg_capability {
322 	size_t key_len;
323 	size_t value_len;
324 
325 	/*
326 	 * Followed by key_len + value_len data bytes.
327 	 */
328 } __attribute__((__packed__));
329 
330 /* Structure for GOTD_IMSG_WANT data. */
331 struct gotd_imsg_want {
332 	uint8_t object_id[SHA1_DIGEST_LENGTH];
333 } __attribute__((__packed__));
334 
335 /* Structure for GOTD_IMSG_HAVE data. */
336 struct gotd_imsg_have {
337 	uint8_t object_id[SHA1_DIGEST_LENGTH];
338 } __attribute__((__packed__));
339 
340 /* Structure for GOTD_IMSG_ACK data. */
341 struct gotd_imsg_ack {
342 	uint8_t object_id[SHA1_DIGEST_LENGTH];
343 } __attribute__((__packed__));
344 
345 /* Structure for GOTD_IMSG_NAK data. */
346 struct gotd_imsg_nak {
347 	uint8_t object_id[SHA1_DIGEST_LENGTH];
348 } __attribute__((__packed__));
349 
350 /* Structure for GOTD_IMSG_PACKFILE_STATUS data. */
351 struct gotd_imsg_packfile_status {
352 	size_t reason_len;
353 
354 	/* Followed by reason_len data bytes. */
355 } __attribute__((__packed__));
356 
357 
358 /* Structure for GOTD_IMSG_REF_UPDATE data. */
359 struct gotd_imsg_ref_update {
360 	uint8_t old_id[SHA1_DIGEST_LENGTH];
361 	uint8_t new_id[SHA1_DIGEST_LENGTH];
362 	int ref_is_new;
363 	int delete_ref;
364 	size_t name_len;
365 
366 	/* Followed by name_len data bytes. */
367 } __attribute__((__packed__));
368 
369 /* Structure for GOTD_IMSG_REF_UPDATES_START data. */
370 struct gotd_imsg_ref_updates_start {
371 	int nref_updates;
372 
373 	/* Followed by nref_updates GOT_IMSG_REF_UPDATE_OK/NG messages. */
374 };
375 
376 /* Structure for GOTD_IMSG_REF_UPDATE_OK data. */
377 struct gotd_imsg_ref_update_ok {
378 	uint8_t old_id[SHA1_DIGEST_LENGTH];
379 	uint8_t new_id[SHA1_DIGEST_LENGTH];
380 	int ref_is_new;
381 	size_t name_len;
382 
383 	/* Followed by name_len data bytes. */
384 } __attribute__((__packed__));
385 
386 /* Structure for GOTD_IMSG_REF_UPDATE_NG data. */
387 struct gotd_imsg_ref_update_ng {
388 	uint8_t old_id[SHA1_DIGEST_LENGTH];
389 	uint8_t new_id[SHA1_DIGEST_LENGTH];
390 	size_t name_len;
391 	size_t reason_len;
392 
393 	/* Followed by name_len + reason_len data bytes. */
394 } __attribute__((__packed__));
395 
396 /* Structure for GOTD_IMSG_SEND_PACKFILE data. */
397 struct gotd_imsg_send_packfile {
398 	int report_progress;
399 
400 	/* delta cache file is sent as a file descriptor */
401 
402 	/* followed by two GOTD_IMSG_PACKFILE_PIPE messages */
403 };
404 
405 /* Structure for GOTD_IMSG_RECV_PACKFILE data. */
406 struct gotd_imsg_recv_packfile {
407 	int report_status;
408 
409 	/* pack destination temp file is sent as a file descriptor */
410 };
411 
412 /*
413  * Structure for GOTD_IMSG_PACKFILE_PROGRESS and
414  * GOTD_IMSG_PACKFILE_READY data.
415  */
416 struct gotd_imsg_packfile_progress {
417 	int ncolored;
418 	int nfound;
419 	int ntrees;
420 	off_t packfile_size;
421 	int ncommits;
422 	int nobj_total;
423 	int nobj_deltify;
424 	int nobj_written;
425 };
426 
427 /* Structure for GOTD_IMSG_PACKFILE_INSTALL. */
428 struct gotd_imsg_packfile_install {
429 	uint8_t pack_sha1[SHA1_DIGEST_LENGTH];
430 };
431 
432 /* Structure for GOTD_IMSG_DISCONNECT data. */
433 struct gotd_imsg_disconnect {
434 	uint32_t client_id;
435 };
436 
437 /* Structure for GOTD_IMSG_CONNECT. */
438 struct gotd_imsg_connect {
439 	uint32_t client_id;
440 	uid_t euid;
441 	gid_t egid;
442 	size_t username_len;
443 
444 	/* Followed by username_len data bytes. */
445 };
446 
447 /* Structure for GOTD_IMSG_CONNECT_REPO_CHILD. */
448 struct gotd_imsg_connect_repo_child {
449 	enum gotd_procid proc_id;
450 
451 	/* repo child imsg pipe is passed via imsg fd */
452 };
453 
454 /* Structure for GOTD_IMSG_AUTHENTICATE. */
455 struct gotd_imsg_auth {
456 	uid_t euid;
457 	gid_t egid;
458 	int required_auth;
459 	uint32_t client_id;
460 };
461 
462 /* Structures for GOTD_IMSG_NOTIFY. */
463 enum gotd_notification_action {
464 	GOTD_NOTIF_ACTION_CREATED,
465 	GOTD_NOTIF_ACTION_REMOVED,
466 	GOTD_NOTIF_ACTION_CHANGED
467 };
468 /* IMSG_NOTIFY session <-> repo_write */
469 struct gotd_imsg_notification_content {
470 	enum gotd_notification_action action;
471 	uint8_t old_id[SHA1_DIGEST_LENGTH];
472 	uint8_t new_id[SHA1_DIGEST_LENGTH];
473 	size_t refname_len;
474 	/* Followed by refname_len data bytes. */
475 };
476 /* IMSG_NOTIFY session -> notify*/
477 struct gotd_imsg_notify {
478 	char repo_name[NAME_MAX];
479 	char subject_line[64];
480 };
481 
482 int parse_config(const char *, enum gotd_procid, struct gotd *);
483 struct gotd_repo *gotd_find_repo_by_name(const char *, struct gotd_repolist *);
484 struct gotd_repo *gotd_find_repo_by_path(const char *, struct gotd *);
485 struct gotd_uid_connection_limit *gotd_find_uid_connection_limit(
486     struct gotd_uid_connection_limit *limits, size_t nlimits, uid_t uid);
487 int gotd_parseuid(const char *s, uid_t *uid);
488 const struct got_error *gotd_parse_url(char **, char **, char **,
489     char **, const char *);
490 
491 /* imsg.c */
492 const struct got_error *gotd_imsg_flush(struct imsgbuf *);
493 const struct got_error *gotd_imsg_recv(struct imsg *, struct imsgbuf *, size_t);
494 const struct got_error *gotd_imsg_poll_recv(struct imsg *, struct imsgbuf *,
495     size_t);
496 const struct got_error *gotd_imsg_recv_error(uint32_t *client_id,
497     struct imsg *imsg);
498 int gotd_imsg_send_error(struct imsgbuf *ibuf, uint32_t, uint32_t,
499     const struct got_error *);
500 int gotd_imsg_send_error_event(struct gotd_imsgev *, uint32_t, uint32_t,
501     const struct got_error *);
502 void gotd_imsg_event_add(struct gotd_imsgev *);
503 int gotd_imsg_compose_event(struct gotd_imsgev *, uint16_t, uint32_t, int,
504     void *, uint16_t);
505 int gotd_imsg_forward(struct gotd_imsgev *, struct imsg *, int);
506 
507 void gotd_imsg_send_ack(struct got_object_id *, struct imsgbuf *,
508     uint32_t, pid_t);
509 void gotd_imsg_send_nak(struct got_object_id *, struct imsgbuf *,
510     uint32_t, pid_t);