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_NAME_MAX		511
81 #define FCGI_VAL_MAX		511
82 
83 #define FCGI_MAX	32
84 #define PREFORK_MAX	16
85 
86 struct iri {
87 	char		*schema;
88 	char		*host;
89 	char		*port;
90 	uint16_t	 port_no;
91 	char		*path;
92 	char		*query;
93 	char		*fragment;
94 };
95 
96 struct parser {
97 	char		*iri;
98 	struct iri	*parsed;
99 	const char	*err;
100 };
101 
102 struct fcgi {
103 	int		 id;
104 	char		 path[PATH_MAX];
105 	char		 port[32];
106 };
107 extern struct fcgi fcgi[FCGI_MAX];
108 
109 TAILQ_HEAD(proxyhead, proxy);
110 struct proxy {
111 	char		 match_proto[32];
112 	char		 match_host[HOST_NAME_MAX + 1];
113 	char		 match_port[32];
114 
115 	char		 host[HOST_NAME_MAX + 1];
116 	char		 port[32];
117 	char		 sni[HOST_NAME_MAX];
118 	int		 notls;
119 	uint32_t	 protocols;
120 	int		 noverifyname;
121 	uint8_t		*cert;
122 	size_t		 certlen;
123 	uint8_t		*key;
124 	size_t		 keylen;
125 	X509_STORE	*reqca;
126 
127 	TAILQ_ENTRY(proxy) proxies;
128 };
129 
130 TAILQ_HEAD(lochead, location);
131 struct location {
132 	char		 match[128];
133 	char		 lang[32];
134 	char		 default_mime[MEDIATYPE_TYPEMAX];
135 	char		 index[PATH_MAX];
136 	int		 auto_index; /* 0 auto, -1 off, 1 on */
137 	int		 block_code;
138 	char		 block_fmt[GEMINI_URL_LEN];
139 	int		 strip;
140 	X509_STORE	*reqca;
141 	int		 disable_log;
142 	int		 fcgi;
143 
144 	char		 dir[PATH_MAX];
145 	int		 dirfd;
146 
147 	TAILQ_ENTRY(location) locations;
148 };
149 
150 TAILQ_HEAD(envhead, envlist);
151 struct envlist {
152 	char		 name[FCGI_NAME_MAX];
153 	char		 value[FCGI_VAL_MAX];
154 	TAILQ_ENTRY(envlist) envs;
155 };
156 
157 TAILQ_HEAD(aliashead, alist);
158 struct alist {
159 	char		alias[HOST_NAME_MAX + 1];
160 	TAILQ_ENTRY(alist) aliases;
161 };
162 
163 extern TAILQ_HEAD(vhosthead, vhost) hosts;
164 struct vhost {
165 	char		 domain[HOST_NAME_MAX + 1];
166 	char		 cert[PATH_MAX];
167 	char		 key[PATH_MAX];
168 	char		 ocsp[PATH_MAX];
169 
170 	TAILQ_ENTRY(vhost) vhosts;
171 
172 	/*
173 	 * the first location rule is always '*' and holds the default
174 	 * settings for the vhost, then follows the "real" location
175 	 * rules as specified in the configuration.
176 	 */
177 	struct lochead	 locations;
178 
179 	struct envhead	 params;
180 	struct aliashead aliases;
181 	struct proxyhead proxies;
182 };
183 
184 struct etm {			/* extension to mime */
185 	char	 mime[MEDIATYPE_TYPEMAX];
186 	char	 ext[MEDIATYPE_NAMEMAX];
187 };
188 
189 struct mime {
190 	struct etm	*t;
191 	size_t		 len;
192 	size_t		 cap;
193 };
194 
195 struct conf {
196 	/* from command line */
197 	int		 foreground;
198 	int		 verbose;
199 
200 	/* in the config */
201 	int		 port;
202 	int		 ipv6;
203 	uint32_t	 protos;
204 	struct mime	 mime;
205 	char		 chroot[PATH_MAX];
206 	char		 user[LOGIN_NAME_MAX];
207 	int		 prefork;
208 };
209 
210 extern const char *config_path;
211 extern struct conf conf;
212 
213 extern struct imsgbuf logibuf, servibuf[PREFORK_MAX];
214 
215 extern int servpipes[PREFORK_MAX];
216 
217 typedef void (imsg_handlerfn)(struct imsgbuf*, struct imsg*, size_t);
218 
219 enum {
220 	REQUEST_UNDECIDED,
221 	REQUEST_FILE,
222 	REQUEST_DIR,
223 	REQUEST_FCGI,
224 	REQUEST_PROXY,
225 	REQUEST_DONE,
226 };
227 
228 struct client {
229 	uint32_t	 id;
230 	struct tls	*ctx;
231 	char		*req;
232 	size_t		 reqlen;
233 	struct iri	 iri;
234 	char		 domain[DOMAIN_NAME_LEN];
235 
236 	struct bufferevent *bev;
237 
238 	int		 type;
239 
240 	struct bufferevent *cgibev;
241 
242 	struct proxy	*proxy;
243 	struct bufferevent *proxybev;
244 	struct tls	*proxyctx;
245 	int		 proxyevset;
246 	struct event	 proxyev;
247 
248 	char		*header;
249 
250 	int		 code;
251 	const char	*meta;
252 	int		 fd, pfd;
253 	struct dirent	**dir;
254 	int		 dirlen, diroff;
255 
256 	/* big enough to store STATUS + SPACE + META + CRLF */
257 	char		 sbuf[1029];
258 	ssize_t		 len, off;
259 
260 	struct sockaddr_storage	 addr;
261 	struct vhost	*host;	/* host they're talking to */
262 	size_t		 loc;	/* location matched */
263 
264 	SPLAY_ENTRY(client) entry;
265 };
266 SPLAY_HEAD(client_tree_id, client);
267 extern struct client_tree_id clients;
268 
269 struct connreq {
270 	char	host[NI_MAXHOST];
271 	char	port[NI_MAXSERV];
272 	int	flag;
273 };
274 
275 enum {
276 	FILE_EXISTS,
277 	FILE_DIRECTORY,
278 	FILE_MISSING,
279 };
280 
281 enum imsg_type {
282 	IMSG_FCGI_REQ,
283 	IMSG_FCGI_FD,
284 	IMSG_CONN_REQ,
285 	IMSG_CONN_FD,
286 	IMSG_LOG,
287 	IMSG_LOG_REQUEST,
288 	IMSG_LOG_TYPE,
289 	IMSG_QUIT,
290 };
291 
292 /* gmid.c */
293 char		*data_dir(void);
294 void		 load_local_cert(struct vhost*, const char*, const char*);
295 int		 make_socket(int, int);
296 void		 drop_priv(void);
297 
298 /* config.c */
299 void		 config_init(void);
300 void		 config_free(void);
301 
302 /* parse.y */
303 void		 yyerror(const char*, ...);
304 void		 parse_conf(const char*);
305 void		 print_conf(void);
306 int		 cmdline_symset(char *);
307 
308 /* mime.c */
309 void		 init_mime(struct mime*);
310 int		 add_mime(struct mime*, const char*, const char*);
311 int		 load_default_mime(struct mime*);
312 void		 sort_mime(struct mime *);
313 const char	*mime(struct vhost*, const char*);
314 void		 free_mime(struct mime *);
315 
316 /* server.c */
317 extern int	shutting_down;
318 const char	*vhost_lang(struct vhost*, const char*);
319 const char	*vhost_default_mime(struct vhost*, const char*);
320 const char	*vhost_index(struct vhost*, const char*);
321 int		 vhost_auto_index(struct vhost*, const char*);
322 int		 vhost_block_return(struct vhost*, const char*, int*, const char**);
323 int		 vhost_fastcgi(struct vhost*, const char*);
324 int		 vhost_dirfd(struct vhost*, const char*, size_t*);
325 int		 vhost_strip(struct vhost*, const char*);
326 X509_STORE	*vhost_require_ca(struct vhost*, const char*);
327 int		 vhost_disable_log(struct vhost*, const char*);
328 
329 void		 mark_nonblock(int);
330 void		 client_write(struct bufferevent *, void *);
331 void		 start_reply(struct client*, int, const char*);
332 void		 client_close(struct client *);
333 struct client	*client_by_id(int);
334 int		 server_main(struct imsgbuf *, int, int);
335 
336 int		 client_tree_cmp(struct client *, struct client *);
337 SPLAY_PROTOTYPE(client_tree_id, client, entry, client_tree_cmp);
338 
339 /* dirs.c */
340 int		 scandir_fd(int, struct dirent***, int(*)(const struct dirent*),
341 		    int(*)(const struct dirent**, const struct dirent**));
342 int		 select_non_dot(const struct dirent*);
343 int		 select_non_dotdot(const struct dirent*);
344 
345 /* fcgi.c */
346 void		 fcgi_read(struct bufferevent *, void *);
347 void		 fcgi_write(struct bufferevent *, void *);
348 void		 fcgi_error(struct bufferevent *, short, void *);
349 void		 fcgi_req(struct client *);
350 
351 /* sandbox.c */
352 void		 sandbox_server_process(void);
353 void		 sandbox_logger_process(void);
354 
355 /* utf8.c */
356 int		 valid_multibyte_utf8(struct parser*);
357 char		*utf8_nth(char*, size_t);
358 
359 /* iri.c */
360 int		 parse_iri(char*, struct iri*, const char**);
361 int		 serialize_iri(struct iri*, char*, size_t);
362 int		 encode_path(char *, size_t, const char *);
363 char		*pct_decode_str(char *);
364 
365 /* proxy.c */
366 int		 proxy_init(struct client *);
367 
368 /* puny.c */
369 int		 puny_decode(const char*, char*, size_t, const char**);
370 
371 /* utils.c */
372 void		 block_signals(void);
373 void		 unblock_signals(void);
374 int		 starts_with(const char*, const char*);
375 int		 ends_with(const char*, const char*);
376 ssize_t		 filesize(int);
377 char		*absolutify_path(const char*);
378 char		*xstrdup(const char*);
379 void		*xcalloc(size_t, size_t);
380 void		 gen_certificate(const char*, const char*, const char*);
381 X509_STORE	*load_ca(const char*);
382 int		 validate_against_ca(X509_STORE*, const uint8_t*, size_t);
383 void		 dispatch_imsg(struct imsgbuf*, imsg_handlerfn**, size_t);
384 
385 #endif