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