1 /*
2  * Copyright (c) 2020, 2021, 2022 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 #define GMID_STRING	"gmid " VERSION
54 #define GMID_VERSION	"gmid/" VERSION
55 
56 #define GEMINI_URL_LEN (1024+3)	/* URL max len + \r\n + \0 */
57 
58 #define SUCCESS		20
59 #define TEMP_REDIRECT	30
60 #define TEMP_FAILURE	40
61 #define CGI_ERROR	42
62 #define PROXY_ERROR	43
63 #define NOT_FOUND	51
64 #define PROXY_REFUSED	53
65 #define BAD_REQUEST	59
66 #define CLIENT_CERT_REQ	60
67 #define CERT_NOT_AUTH	61
68 
69 /* maximum hostname and label length, +1 for the NUL-terminator */
70 #define DOMAIN_NAME_LEN	(253+1)
71 #define LABEL_LEN	(63+1)
72 
73 #define MEDIATYPE_NAMEMAX	128	/* file name extension */
74 #define MEDIATYPE_TYPEMAX	128	/* length of type/subtype */
75 
76 #define FCGI_MAX	32
77 #define PROC_MAX	16
78 
79 struct iri {
80 	char		*schema;
81 	char		*host;
82 	char		*port;
83 	uint16_t	 port_no;
84 	char		*path;
85 	char		*query;
86 	char		*fragment;
87 };
88 
89 struct parser {
90 	char		*iri;
91 	struct iri	*parsed;
92 	const char	*err;
93 };
94 
95 struct fcgi {
96 	int		 id;
97 	char		*path;
98 	char		*port;
99 	char		*prog;
100 };
101 extern struct fcgi fcgi[FCGI_MAX];
102 
103 TAILQ_HEAD(proxyhead, proxy);
104 struct proxy {
105 	char		*match_proto;
106 	char		*match_host;
107 	const char	*match_port;
108 
109 	char		*host;
110 	const char	*port;
111 	char		*sni;
112 	int		 notls;
113 	uint32_t	 protocols;
114 	int		 noverifyname;
115 	uint8_t		*cert;
116 	size_t		 certlen;
117 	uint8_t		*key;
118 	size_t		 keylen;
119 	X509_STORE	*reqca;
120 
121 	TAILQ_ENTRY(proxy) proxies;
122 };
123 
124 TAILQ_HEAD(lochead, location);
125 struct location {
126 	const char	*match;
127 	const char	*lang;
128 	const char	*default_mime;
129 	const char	*index;
130 	int		 auto_index; /* 0 auto, -1 off, 1 on */
131 	int		 block_code;
132 	const char	*block_fmt;
133 	int		 strip;
134 	X509_STORE	*reqca;
135 	int		 disable_log;
136 	int		 fcgi;
137 
138 	const char	*dir;
139 	int		 dirfd;
140 
141 	TAILQ_ENTRY(location) locations;
142 };
143 
144 TAILQ_HEAD(envhead, envlist);
145 struct envlist {
146 	char		*name;
147 	char		*value;
148 	TAILQ_ENTRY(envlist) envs;
149 };
150 
151 TAILQ_HEAD(aliashead, alist);
152 struct alist {
153 	char		*alias;
154 	TAILQ_ENTRY(alist) aliases;
155 };
156 
157 extern TAILQ_HEAD(vhosthead, vhost) hosts;
158 struct vhost {
159 	const char	*domain;
160 	const char	*cert;
161 	const char	*key;
162 	const char	*ocsp;
163 	const char	*entrypoint;
164 
165 	TAILQ_ENTRY(vhost) vhosts;
166 
167 	/*
168 	 * the first location rule is always '*' and holds the default
169 	 * settings for the vhost, then follows the "real" location
170 	 * rules as specified in the configuration.
171 	 */
172 	struct lochead	 locations;
173 
174 	struct envhead	 env;
175 	struct envhead	 params;
176 	struct aliashead aliases;
177 	struct proxyhead proxies;
178 };
179 
180 struct etm {			/* extension to mime */
181 	char	 mime[MEDIATYPE_TYPEMAX];
182 	char	 ext[MEDIATYPE_NAMEMAX];
183 };
184 
185 struct mime {
186 	struct etm	*t;
187 	size_t		 len;
188 	size_t		 cap;
189 };
190 
191 struct conf {
192 	/* from command line */
193 	int		 foreground;
194 	int		 verbose;
195 	int		 can_open_sockets;
196 
197 	/* in the config */
198 	int		 port;
199 	int		 ipv6;
200 	uint32_t	 protos;
201 	struct mime	 mime;
202 	char		 chroot[PATH_MAX];
203 	char		 user[LOGIN_NAME_MAX];
204 	int		 prefork;
205 };
206 
207 extern const char *config_path;
208 extern struct conf conf;
209 
210 extern struct imsgbuf logibuf, exibuf, servibuf[PROC_MAX];
211 
212 extern int servpipes[PROC_MAX];
213 
214 typedef void (imsg_handlerfn)(struct imsgbuf*, struct imsg*, size_t);
215 
216 enum {
217 	REQUEST_UNDECIDED,
218 	REQUEST_FILE,
219 	REQUEST_DIR,
220 	REQUEST_FCGI,
221 	REQUEST_PROXY,
222 	REQUEST_DONE,
223 };
224 
225 #define IS_INTERNAL_REQUEST(x) \
226 	 (x) != REQUEST_FCGI && \
227 	 (x) != REQUEST_PROXY)
228 
229 struct client {
230 	uint32_t	 id;
231 	struct tls	*ctx;
232 	char		*req;
233 	size_t		 reqlen;
234 	struct iri	 iri;
235 	char		 domain[DOMAIN_NAME_LEN];
236 
237 	struct bufferevent *bev;
238 
239 	int		 type;
240 
241 	struct bufferevent *cgibev;
242 
243 	struct proxy	*proxy;
244 	struct bufferevent *proxybev;
245 	struct tls	*proxyctx;
246 	int		 proxyevset;
247 	struct event	 proxyev;
248 
249 	char		*header;
250 
251 	int		 code;
252 	const char	*meta;
253 	int		 fd, pfd;
254 	struct dirent	**dir;
255 	int		 dirlen, diroff;
256 
257 	/* big enough to store STATUS + SPACE + META + CRLF */
258 	char		 sbuf[1029];
259 	ssize_t		 len, off;
260 
261 	struct sockaddr_storage	 addr;
262 	struct vhost	*host;	/* host they're talking to */
263 	size_t		 loc;	/* location matched */
264 
265 	SPLAY_ENTRY(client) entry;
266 };
267 SPLAY_HEAD(client_tree_id, client);
268 extern struct client_tree_id clients;
269 
270 struct connreq {
271 	char	host[NI_MAXHOST];
272 	char	port[NI_MAXSERV];
273 	int	flag;
274 };
275 
276 enum {
277 	FILE_EXISTS,
278 	FILE_DIRECTORY,
279 	FILE_MISSING,
280 };
281 
282 enum imsg_type {
283 	IMSG_FCGI_REQ,
284 	IMSG_FCGI_FD,
285 	IMSG_CONN_REQ,
286 	IMSG_CONN_FD,
287 	IMSG_LOG,
288 	IMSG_LOG_REQUEST,
289 	IMSG_LOG_TYPE,
290 	IMSG_QUIT,
291 };
292 
293 /* gmid.c */
294 char		*data_dir(void);
295 void		 load_local_cert(struct vhost*, const char*, const char*);
296 void		 load_vhosts(void);
297 int		 make_socket(int, int);
298 void		 setup_tls(void);
299 void		 init_config(void);
300 void		 free_config(void);
301 void		 drop_priv(void);
302 
303 void		 yyerror(const char*, ...);
304 void		 parse_conf(const char*);
305 void		 print_conf(void);
306 int		 cmdline_symset(char *);
307 
308 /* log.c */
309 void		 fatal(const char*, ...)
310 	__attribute__((format (printf, 1, 2)))
311 	__attribute__((__noreturn__));
312 
313 #define LOG_ATTR_FMT __attribute__((format (printf, 2, 3)))
314 void		 log_err(struct client*, const char*, ...)	LOG_ATTR_FMT;
315 void		 log_warn(struct client*, const char*, ...)	LOG_ATTR_FMT;
316 void		 log_notice(struct client*, const char*, ...)	LOG_ATTR_FMT;
317 void		 log_info(struct client*, const char*, ...)	LOG_ATTR_FMT;
318 void		 log_debug(struct client*, const char*, ...)	LOG_ATTR_FMT;
319 void		 log_request(struct client*, char*, size_t);
320 int		 logger_main(int, struct imsgbuf*);
321 
322 /* mime.c */
323 void		 init_mime(struct mime*);
324 int		 add_mime(struct mime*, const char*, const char*);
325 int		 load_default_mime(struct mime*);
326 void		 sort_mime(struct mime *);
327 const char	*mime(struct vhost*, const char*);
328 void		 free_mime(struct mime *);
329 
330 /* server.c */
331 extern int	shutting_down;
332 const char	*vhost_lang(struct vhost*, const char*);
333 const char	*vhost_default_mime(struct vhost*, const char*);
334 const char	*vhost_index(struct vhost*, const char*);
335 int		 vhost_auto_index(struct vhost*, const char*);
336 int		 vhost_block_return(struct vhost*, const char*, int*, const char**);
337 int		 vhost_fastcgi(struct vhost*, const char*);
338 int		 vhost_dirfd(struct vhost*, const char*, size_t*);
339 int		 vhost_strip(struct vhost*, const char*);
340 X509_STORE	*vhost_require_ca(struct vhost*, const char*);
341 int		 vhost_disable_log(struct vhost*, const char*);
342 
343 void		 mark_nonblock(int);
344 void		 client_write(struct bufferevent *, void *);
345 void		 start_reply(struct client*, int, const char*);
346 void		 client_close(struct client *);
347 struct client	*client_by_id(int);
348 void		 loop(struct tls*, int, int, struct imsgbuf*);
349 
350 int		 client_tree_cmp(struct client *, struct client *);
351 SPLAY_PROTOTYPE(client_tree_id, client, entry, client_tree_cmp);
352 
353 /* dirs.c */
354 int		 scandir_fd(int, struct dirent***, int(*)(const struct dirent*),
355 		    int(*)(const struct dirent**, const struct dirent**));
356 int		 select_non_dot(const struct dirent*);
357 int		 select_non_dotdot(const struct dirent*);
358 
359 /* fcgi.c */
360 void		 fcgi_read(struct bufferevent *, void *);
361 void		 fcgi_write(struct bufferevent *, void *);
362 void		 fcgi_error(struct bufferevent *, short, void *);
363 void		 fcgi_req(struct client *);
364 
365 /* sandbox.c */
366 void		 sandbox_server_process(int);
367 void		 sandbox_logger_process(void);
368 
369 /* utf8.c */
370 int		 valid_multibyte_utf8(struct parser*);
371 char		*utf8_nth(char*, size_t);
372 
373 /* iri.c */
374 int		 parse_iri(char*, struct iri*, const char**);
375 int		 serialize_iri(struct iri*, char*, size_t);
376 int		 encode_path(char *, size_t, const char *);
377 char		*pct_decode_str(char *);
378 
379 /* proxy.c */
380 int		 proxy_init(struct client *);
381 
382 /* puny.c */
383 int		 puny_decode(const char*, char*, size_t, const char**);
384 
385 /* utils.c */
386 void		 block_signals(void);
387 void		 unblock_signals(void);
388 int		 starts_with(const char*, const char*);
389 int		 ends_with(const char*, const char*);
390 ssize_t		 filesize(int);
391 char		*absolutify_path(const char*);
392 char		*xstrdup(const char*);
393 void		*xcalloc(size_t, size_t);
394 void		 gen_certificate(const char*, const char*, const char*);
395 X509_STORE	*load_ca(const char*);
396 int		 validate_against_ca(X509_STORE*, const uint8_t*, size_t);
397 void		 dispatch_imsg(struct imsgbuf*, imsg_handlerfn**, size_t);
398 
399 #endif