1 /*
2  * Copyright (c) 2020, 2021, 2022, 2023 Omar Polo <op@omarpolo.com>
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 #ifndef GMID_H
18 #define GMID_H
19 
20 #include "config.h"
21 
22 #include <sys/socket.h>
23 #include <sys/types.h>
24 
25 #include <arpa/inet.h>
26 #include <netinet/in.h>
27 
28 #include <dirent.h>
29 #include <limits.h>
30 #include <netdb.h>
31 #include <signal.h>
32 #include <stdio.h>
33 #include <stdlib.h>
34 #include <time.h>
35 #include <tls.h>
36 #include <unistd.h>
37 
38 #include <openssl/x509.h>
39 
40 #if HAVE_EVENT2
41 # include <event2/event.h>
42 # include <event2/event_compat.h>
43 # include <event2/event_struct.h>
44 # include <event2/buffer.h>
45 # include <event2/buffer_compat.h>
46 # include <event2/bufferevent.h>
47 # include <event2/bufferevent_struct.h>
48 # include <event2/bufferevent_compat.h>
49 #else
50 # include <event.h>
51 #endif
52 
53 #include "iri.h"
54 
55 #define VERSION_STR(n)	n " " VERSION
56 #define GE_STRING	VERSION_STR("ge")
57 #define GG_STRING	VERSION_STR("gg")
58 #define GMID_STRING	VERSION_STR("gmid")
59 
60 #define GMID_VERSION	"gmid/" VERSION
61 
62 #define GEMINI_URL_LEN (1024+3)	/* URL max len + \r\n + \0 */
63 
64 #define SUCCESS		20
65 #define TEMP_REDIRECT	30
66 #define TEMP_FAILURE	40
67 #define CGI_ERROR	42
68 #define PROXY_ERROR	43
69 #define NOT_FOUND	51
70 #define PROXY_REFUSED	53
71 #define BAD_REQUEST	59
72 #define CLIENT_CERT_REQ	60
73 #define CERT_NOT_AUTH	61
74 
75 /* maximum hostname and label length, +1 for the NUL-terminator */
76 #define DOMAIN_NAME_LEN	(253+1)
77 #define LABEL_LEN	(63+1)
78 
79 #define MEDIATYPE_NAMEMAX	128	/* file name extension */
80 #define MEDIATYPE_TYPEMAX	128	/* length of type/subtype */
81 
82 #define FCGI_NAME_MAX		511
83 #define FCGI_VAL_MAX		511
84 
85 #define PROC_MAX_INSTANCES	16
86 
87 #define TLS_CERT_HASH_SIZE	128
88 
89 /* forward declaration */
90 struct privsep;
91 struct privsep_proc;
92 
93 struct parser {
94 	char		*iri;
95 	struct iri	*parsed;
96 	const char	*err;
97 };
98 
99 struct conf;
100 TAILQ_HEAD(addrhead, address);
101 struct address {
102 	int			 ai_flags;
103 	int			 ai_family;
104 	int			 ai_socktype;
105 	int			 ai_protocol;
106 	struct sockaddr_storage	 ss;
107 	socklen_t		 slen;
108 	int16_t			 port;
109 
110 	/* used in the server */
111 	struct conf		*conf;
112 	int			 sock;
113 	struct event		 evsock; /* set if sock != -1 */
114 	struct tls		*ctx;
115 
116 	TAILQ_ENTRY(address)	 addrs;
117 };
118 
119 TAILQ_HEAD(fcgihead, fcgi);
120 struct fcgi {
121 	int		 id;
122 	char		 path[PATH_MAX];
123 	char		 port[32];
124 	TAILQ_ENTRY(fcgi) fcgi;
125 };
126 
127 TAILQ_HEAD(envhead, envlist);
128 struct envlist {
129 	char		 name[FCGI_NAME_MAX];
130 	char		 value[FCGI_VAL_MAX];
131 	TAILQ_ENTRY(envlist) envs;
132 };
133 
134 TAILQ_HEAD(aliashead, alist);
135 struct alist {
136 	char		alias[HOST_NAME_MAX + 1];
137 	TAILQ_ENTRY(alist) aliases;
138 };
139 
140 TAILQ_HEAD(proxyhead, proxy);
141 struct proxy {
142 	char		 match_proto[32];
143 	char		 match_host[HOST_NAME_MAX + 1];
144 	char		 match_port[32];
145 
146 	char		 host[HOST_NAME_MAX + 1];
147 	char		 port[32];
148 	char		 sni[HOST_NAME_MAX];
149 	int		 notls;
150 	uint32_t	 protocols;
151 	int		 noverifyname;
152 	char		*cert_path;
153 	uint8_t		*cert;
154 	size_t		 certlen;
155 	char		*key_path;
156 	uint8_t		*key;
157 	size_t		 keylen;
158 	char		*reqca_path;
159 	X509_STORE	*reqca;
160 
161 	TAILQ_ENTRY(proxy) proxies;
162 };
163 
164 TAILQ_HEAD(lochead, location);
165 struct location {
166 	char		 match[128];
167 	char		 lang[32];
168 	char		 default_mime[MEDIATYPE_TYPEMAX];
169 	char		 index[PATH_MAX];
170 	int		 auto_index; /* 0 auto, -1 off, 1 on */
171 	int		 block_code;
172 	char		 block_fmt[GEMINI_URL_LEN];
173 	int		 strip;
174 	char		*reqca_path;
175 	X509_STORE	*reqca;
176 	int		 disable_log;
177 	int		 fcgi;
178 	int		 nofcgi;
179 	struct envhead	 params;
180 
181 	char		 dir[PATH_MAX];
182 	int		 dirfd;
183 
184 	TAILQ_ENTRY(location) locations;
185 };
186 
187 TAILQ_HEAD(vhosthead, vhost);
188 struct vhost {
189 	char		 domain[HOST_NAME_MAX + 1];
190 	char		*cert_path;
191 	char		*key_path;
192 	char		*ocsp_path;
193 
194 	uint8_t		*cert;
195 	size_t		 certlen;
196 
197 	uint8_t		*key;
198 	size_t		 keylen;
199 
200 	uint8_t		*ocsp;
201 	size_t		 ocsplen;
202 
203 	TAILQ_ENTRY(vhost) vhosts;
204 
205 	struct addrhead	 addrs;
206 
207 	/*
208 	 * the first location rule is always '*' and holds the default
209 	 * settings for the vhost, then follows the "real" location
210 	 * rules as specified in the configuration.
211 	 */
212 	struct lochead	 locations;
213 
214 	struct aliashead aliases;
215 	struct proxyhead proxies;
216 };
217 
218 struct etm {			/* extension to mime */
219 	char	 mime[MEDIATYPE_TYPEMAX];
220 	char	 ext[MEDIATYPE_NAMEMAX];
221 };
222 
223 struct mime {
224 	struct etm	*t;
225 	size_t		 len;
226 	size_t		 cap;
227 };
228 
229 TAILQ_HEAD(pkihead, pki);
230 struct pki {
231 	char		*hash;
232 	EVP_PKEY	*pkey;
233 	TAILQ_ENTRY(pki) pkis;
234 };
235 
236 struct conf {
237 	struct privsep	*ps;
238 	uint32_t	 protos;
239 	struct mime	 mime;
240 	char		 chroot[PATH_MAX];
241 	char		 user[LOGIN_NAME_MAX];
242 	int		 prefork;
243 	int		 reload;
244 	char		*log_access;
245 	int		 use_privsep_crypto;
246 
247 	struct fcgihead	 fcgi;
248 	struct vhosthead hosts;
249 	struct pkihead	 pkis;
250 	struct addrhead	 addrs;
251 };
252 
253 extern const char *config_path;
254 
255 extern int servpipes[PROC_MAX_INSTANCES];
256 extern int privsep_process;
257 
258 typedef void (imsg_handlerfn)(struct imsgbuf*, struct imsg*, size_t);
259 
260 enum {
261 	REQUEST_UNDECIDED,
262 	REQUEST_FILE,
263 	REQUEST_DIR,
264 	REQUEST_FCGI,
265 	REQUEST_PROXY,
266 	REQUEST_DONE,
267 };
268 
269 struct client {
270 	struct conf	*conf;
271 	struct address	*addr;
272 	uint32_t	 id;
273 	struct tls	*ctx;
274 	char		*req;
275 	size_t		 reqlen;
276 	struct iri	 iri;
277 	char		 domain[DOMAIN_NAME_LEN];
278 	char		 rhost[NI_MAXHOST];
279 	char		 rserv[NI_MAXSERV];
280 
281 	struct bufferevent *bev;
282 
283 	int		 type;
284 
285 	struct bufferevent *cgibev;
286 
287 	struct proxy	*proxy;
288 	struct bufferevent *proxybev;
289 	struct tls	*proxyctx;
290 	int		 proxyevset;
291 	struct event	 proxyev;
292 
293 	char		*header;
294 
295 	int		 code;
296 	const char	*meta;
297 	int		 fd, pfd;
298 	struct dirent	**dir;
299 	int		 dirlen, diroff;
300 
301 	/* big enough to store STATUS + SPACE + META + CRLF */
302 	char		 sbuf[1029];
303 	size_t		 soff;
304 
305 	struct sockaddr_storage	 raddr;
306 	socklen_t		 raddrlen;
307 
308 	struct vhost	*host;	/* host they're talking to */
309 	size_t		 loc;	/* location matched */
310 
311 	SPLAY_ENTRY(client) entry;
312 };
313 SPLAY_HEAD(client_tree_id, client);
314 extern struct client_tree_id clients;
315 
316 struct connreq {
317 	char	host[NI_MAXHOST];
318 	char	port[NI_MAXSERV];
319 	int	flag;
320 };
321 
322 enum imsg_type {
323 	IMSG_LOG_REQUEST,
324 	IMSG_LOG_TYPE,
325 
326 	IMSG_RECONF_START,
327 	IMSG_RECONF_MIME,
328 	IMSG_RECONF_PROTOS,
329 	IMSG_RECONF_SOCK,
330 	IMSG_RECONF_FCGI,
331 	IMSG_RECONF_HOST,
332 	IMSG_RECONF_CERT,
333 	IMSG_RECONF_KEY,
334 	IMSG_RECONF_OCSP,
335 	IMSG_RECONF_HOST_ADDR,
336 	IMSG_RECONF_LOC,
337 	IMSG_RECONF_ENV,
338 	IMSG_RECONF_ALIAS,
339 	IMSG_RECONF_PROXY,
340 	IMSG_RECONF_PROXY_CERT,
341 	IMSG_RECONF_PROXY_KEY,
342 	IMSG_RECONF_END,
343 	IMSG_RECONF_DONE,
344 
345 	IMSG_CRYPTO_RSA_PRIVENC,
346 	IMSG_CRYPTO_RSA_PRIVDEC,
347 	IMSG_CRYPTO_ECDSA_SIGN,
348 
349 	IMSG_CTL_PROCFD,
350 };
351 
352 /* gmid.c */
353 char		*data_dir(void);
354 void		 load_local_cert(struct vhost*, const char*, const char*);
355 
356 /* gmid.c / ge.c */
357 void		 log_request(struct client *, int, const char *);
358 
359 /* config.c */
360 struct conf	*config_new(void);
361 void		 config_purge(struct conf *);
362 int		 config_send(struct conf *);
363 int		 config_recv(struct conf *, struct imsg *);
364 
365 /* crypto.c */
366 void		 crypto(struct privsep *, struct privsep_proc *);
367 void		 crypto_engine_init(struct conf *);
368 
369 /* parse.y */
370 void		 yyerror(const char*, ...);
371 int		 parse_conf(struct conf *, const char*);
372 int		 cmdline_symset(char *);
373 
374 /* mime.c */
375 void		 init_mime(struct mime*);
376 int		 add_mime(struct mime*, const char*, const char*);
377 int		 load_default_mime(struct mime*);
378 void		 sort_mime(struct mime *);
379 const char	*mime(struct conf *, struct vhost*, const char*);
380 void		 free_mime(struct mime *);
381 
382 /* server.c */
383 extern int	shutting_down;
384 const char	*vhost_lang(struct vhost*, const char*);
385 const char	*vhost_default_mime(struct vhost*, const char*);
386 const char	*vhost_index(struct vhost*, const char*);
387 int		 vhost_auto_index(struct vhost*, const char*);
388 int		 vhost_block_return(struct vhost*, const char*, int*, const char**);
389 struct location	*vhost_fastcgi(struct vhost*, const char*);
390 int		 vhost_dirfd(struct vhost*, const char*, size_t*);
391 int		 vhost_strip(struct vhost*, const char*);
392 X509_STORE	*vhost_require_ca(struct vhost*, const char*);
393 int		 vhost_disable_log(struct vhost*, const char*);
394 
395 void		 mark_nonblock(int);
396 void		 client_write(struct bufferevent *, void *);
397 void		 start_reply(struct client*, int, const char*);
398 void		 client_close(struct client *);
399 struct client	*client_by_id(int);
400 void		 server_accept(int, short, void *);
401 void		 server_init(struct privsep *, struct privsep_proc *, void *);
402 int		 server_configure_done(struct conf *);
403 void		 server(struct privsep *ps, struct privsep_proc *);
404 
405 int		 client_tree_cmp(struct client *, struct client *);
406 SPLAY_PROTOTYPE(client_tree_id, client, entry, client_tree_cmp);
407 
408 /* dirs.c */
409 int		 scandir_fd(int, struct dirent***, int(*)(const struct dirent*),
410 		    int(*)(const struct dirent**, const struct dirent**));
411 int		 select_non_dot(const struct dirent*);
412 int		 select_non_dotdot(const struct dirent*);
413 
414 /* fcgi.c */
415 void		 fcgi_read(struct bufferevent *, void *);
416 void		 fcgi_write(struct bufferevent *, void *);
417 void		 fcgi_error(struct bufferevent *, short, void *);
418 void		 fcgi_req(struct client *, struct location *);
419 
420 /* sandbox.c */
421 void		 sandbox_main_process(void);
422 void		 sandbox_server_process(void);
423 void		 sandbox_crypto_process(void);
424 void		 sandbox_logger_process(void);
425 
426 /* utf8.c */
427 int		 valid_multibyte_utf8(struct parser*);
428 char		*utf8_nth(char*, size_t);
429 
430 /* logger.c */
431 void		 logger(struct privsep *, struct privsep_proc *);
432 
433 /* proxy.c */
434 int		 proxy_init(struct client *);
435 
436 /* puny.c */
437 int		 puny_decode(const char*, char*, size_t, const char**);
438 
439 /* utils.c */
440 void		 block_signals(void);
441 void		 unblock_signals(void);
442 int		 starts_with(const char*, const char*);
443 int		 ends_with(const char*, const char*);
444 ssize_t		 filesize(int);
445 char		*absolutify_path(const char*);
446 char		*xstrdup(const char*);
447 void		*xcalloc(size_t, size_t);
448 void		 gen_certificate(const char*, const char*, const char*);
449 X509_STORE	*load_ca(uint8_t *, size_t);
450 int		 validate_against_ca(X509_STORE*, const uint8_t*, size_t);
451 void		 ssl_error(const char *);
452 char		*ssl_pubkey_hash(const uint8_t *, size_t);
453 EVP_PKEY	*ssl_load_pkey(const uint8_t *, size_t);
454 struct vhost	*new_vhost(void);
455 struct location	*new_location(void);
456 struct proxy	*new_proxy(void);
457 
458 #endif