1 /*
2  * Copyright (c) 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 #include "gmid.h"
18 
19 #include <sys/stat.h>
20 #include <sys/wait.h>
21 
22 #include <errno.h>
23 #include <fcntl.h>
24 #include <getopt.h>
25 #include <locale.h>
26 #include <libgen.h>
27 #include <signal.h>
28 #include <string.h>
29 #include <syslog.h>
30 #include <unistd.h>
31 
32 #include "log.h"
33 
34 int privsep_process;
35 
36 static const struct option opts[] = {
37 	{"help",	no_argument,	NULL,	'h'},
38 	{"version",	no_argument,	NULL,	'V'},
39 	{NULL,		0,		NULL,	0},
40 };
41 
42 void
43 log_request(struct client *c, char *meta, size_t l)
44 {
45 	char b[GEMINI_URL_LEN];
46 	const char *t;
47 
48 	if (c->iri.schema != NULL) {
49 		/* serialize the IRI */
50 		strlcpy(b, c->iri.schema, sizeof(b));
51 		strlcat(b, "://", sizeof(b));
52 
53 		/* log the decoded host name, but if it was invalid
54 		 * use the raw one. */
55 		if (*c->domain != '\0')
56 			strlcat(b, c->domain, sizeof(b));
57 		else
58 			strlcat(b, c->iri.host, sizeof(b));
59 
60 		if (*c->iri.path != '/')
61 			strlcat(b, "/", sizeof(b));
62 		strlcat(b, c->iri.path, sizeof(b)); /* TODO: sanitize UTF8 */
63 		if (*c->iri.query != '\0') {	    /* TODO: sanitize UTF8 */
64 			strlcat(b, "?", sizeof(b));
65 			strlcat(b, c->iri.query, sizeof(b));
66 		}
67 	} else {
68 		if ((t = c->req) == NULL)
69 			t = "";
70 		strlcpy(b, t, sizeof(b));
71 	}
72 
73 	if ((t = memchr(meta, '\r', l)) == NULL)
74 		t = meta + l;
75 
76 	fprintf(stderr, "%s:%s GET %s %.*s\n", c->rhost, c->rserv, b,
77 	    (int)(t-meta), meta);
78 }
79 
80 void
81 load_local_cert(struct vhost *h, const char *hostname, const char *dir)
82 {
83 	char *cert, *key;
84 
85 	if (asprintf(&cert, "%s/%s.cert.pem", dir, hostname) == -1)
86 		fatal("asprintf");
87 	if (asprintf(&key, "%s/%s.key.pem", dir, hostname) == -1)
88 		fatal("asprintf");
89 
90 	if (access(cert, R_OK) == -1 || access(key, R_OK) == -1)
91 		gen_certificate(hostname, cert, key);
92 
93 	h->cert = tls_load_file(cert, &h->certlen, NULL);
94 	if (h->cert == NULL)
95 		fatal("can't load %s", cert);
96 
97 	h->key = tls_load_file(key, &h->keylen, NULL);
98 	if (h->key == NULL)
99 		fatal("can't load %s", key);
100 
101 	strlcpy(h->domain, hostname, sizeof(h->domain));
102 }
103 
104 /* wrapper around dirname(3).  dn must be PATH_MAX+1 at least. */
105 static void
106 pdirname(const char *path, char *dn)
107 {
108 	char	 p[PATH_MAX+1];
109 	char	*t;
110 
111 	strlcpy(p, path, sizeof(p));
112 	t = dirname(p);
113 	memmove(dn, t, strlen(t)+1);
114 }
115 
116 static void
117 mkdirs(const char *path, mode_t mode)
118 {
119 	char	dname[PATH_MAX+1];
120 
121 	pdirname(path, dname);
122 	if (!strcmp(dname, "/"))
123 		return;
124 	mkdirs(dname, mode);
125 	if (mkdir(path, mode) != 0 && errno != EEXIST)
126 		fatal("can't mkdir %s", path);
127 }
128 
129 /* $XDG_DATA_HOME/gmid */
130 char *
131 data_dir(void)
132 {
133 	const char *home, *xdg;
134 	char *t;
135 
136 	if ((xdg = getenv("XDG_DATA_HOME")) == NULL) {
137 		if ((home = getenv("HOME")) == NULL)
138 			fatalx("XDG_DATA_HOME and HOME both empty");
139 		if (asprintf(&t, "%s/.local/share/gmid", home) == -1)
140 			fatalx("asprintf");
141 	} else {
142 		if (asprintf(&t, "%s/gmid", xdg) == -1)
143 			fatal("asprintf");
144 	}
145 
146 	mkdirs(t, 0755);
147 	return t;
148 }
149 
150 static int
151 serve(struct conf *conf, const char *host, int port, const char *dir)
152 {
153 	struct addrinfo hints, *res, *res0;
154 	struct vhost *vh = TAILQ_FIRST(&conf->hosts);
155 	struct address *addr, *acp;
156 	int r, error, saved_errno, sock = -1;
157 	const char *cause = NULL;
158 	char service[32];
159 	int any = 0;
160 
161 	event_init();
162 
163 	r = snprintf(service, sizeof(service), "%d", port);
164 	if (r < 0 || (size_t)r >= sizeof(service))
165 		fatal("snprintf");
166 
167 	memset(&hints, 0, sizeof(hints));
168 	hints.ai_family = AF_UNSPEC;
169 	hints.ai_socktype = SOCK_STREAM;
170 	hints.ai_flags = AI_PASSIVE;
171 	error = getaddrinfo(host, service, &hints, &res0);
172 	if (error)
173 		fatalx("%s", gai_strerror(error));
174 	for (res = res0; res; res = res->ai_next) {
175 		sock = socket(res->ai_family, res->ai_socktype,
176 		    res->ai_protocol);
177 		if (sock == -1) {
178 			cause = "socket";
179 			continue;
180 		}
181 
182 		if (bind(sock, res->ai_addr, res->ai_addrlen) == -1) {
183 			cause = "bind";
184 			saved_errno = errno;
185 			close(sock);
186 			errno = saved_errno;
187 			continue;
188 		}
189 
190 		if (listen(sock, 5) == -1)
191 			fatal("listen");
192 
193 		any = 1;
194 
195 		addr = xcalloc(1, sizeof(*addr));
196 		addr->ai_flags = res->ai_flags;
197 		addr->ai_family = res->ai_family;
198 		addr->ai_socktype = res->ai_socktype;
199 		addr->ai_protocol = res->ai_protocol;
200 		addr->slen = res->ai_addrlen;
201 		memcpy(&addr->ss, res->ai_addr, res->ai_addrlen);
202 
203 		addr->conf = conf;
204 		addr->sock = sock;
205 		event_set(&addr->evsock, addr->sock, EV_READ|EV_PERSIST,
206 		    do_accept, addr);
207 
208 		if ((addr->ctx = tls_server()) == NULL)
209 			fatal("tls_server failure");
210 
211 		TAILQ_INSERT_HEAD(&conf->addrs, addr, addrs);
212 
213 		acp = xcalloc(1, sizeof(*acp));
214 		memcpy(acp, addr, sizeof(*acp));
215 		acp->sock = -1;
216 		memset(&acp->evsock, 0, sizeof(acp->evsock));
217 		TAILQ_INSERT_HEAD(&vh->addrs, addr, addrs);
218 	}
219 
220 	if (!any)
221 		fatal("%s", cause);
222 	freeaddrinfo(res0);
223 
224 	server_init(NULL, NULL, NULL);
225 	if (server_configure_done(conf) == -1)
226 		fatalx("server configuration failed");
227 
228 	log_info("serving %s on port %d", dir, port);
229 	event_dispatch();
230 	log_info("quitting");
231 	return 0;
232 }
233 
234 static __dead void
235 usage(void)
236 {
237 	fprintf(stderr,
238 	    "Version: " GE_STRING "\n"
239 	    "Usage: %s [-hVv] [-d certs-dir] [-H hostname] [-p port] [dir]\n",
240 	    getprogname());
241 	exit(1);
242 }
243 
244 int
245 main(int argc, char **argv)
246 {
247 	struct conf *conf;
248 	struct vhost *host;
249 	struct location *loc;
250 	const char *errstr, *certs_dir = NULL, *hostname = "localhost";
251 	char path[PATH_MAX];
252 	int ch, port = 1965;
253 
254 	setlocale(LC_CTYPE, "");
255 
256 	log_init(1, LOG_DAEMON);
257 	log_setverbose(0);
258 	conf = config_new();
259 
260 	/* ge doesn't do privsep so no privsep crypto engine. */
261 	conf->use_privsep_crypto = 0;
262 
263 	while ((ch = getopt_long(argc, argv, "d:H:hp:Vv", opts, NULL)) != -1) {
264 		switch (ch) {
265 		case 'd':
266 			certs_dir = optarg;
267 			break;
268 		case 'H':
269 			hostname = optarg;
270 			break;
271 		case 'h':
272 			usage();
273 			break;
274 		case 'p':
275 			port = strtonum(optarg, 0, UINT16_MAX, &errstr);
276 			if (errstr)
277 				fatalx("port number is %s: %s", errstr,
278 				    optarg);
279 			break;
280 		case 'V':
281 			puts("Version: " GE_STRING);
282 			return 0;
283 		default:
284 			usage();
285 			break;
286 		}
287 	}
288 	argc -= optind;
289 	argv += optind;
290 
291 	if (argc > 1)
292 		usage();
293 
294 	/* prepare the configuration */
295 	init_mime(&conf->mime);
296 
297 	if (certs_dir == NULL)
298 		certs_dir = data_dir();
299 
300 	/* set up the implicit vhost and location */
301 	host = xcalloc(1, sizeof(*host));
302 	TAILQ_INSERT_HEAD(&conf->hosts, host, vhosts);
303 
304 	loc = xcalloc(1, sizeof(*loc));
305 	loc->fcgi = -1;
306 	TAILQ_INSERT_HEAD(&host->locations, loc, locations);
307 
308 	load_local_cert(host, hostname, certs_dir);
309 
310 	strlcpy(host->domain, "*", sizeof(host->domain));
311 	loc->auto_index = 1;
312 	strlcpy(loc->match, "*", sizeof(loc->match));
313 
314 	if (*argv == NULL) {
315 		if (getcwd(path, sizeof(path)) == NULL)
316 			fatal("getcwd");
317 		strlcpy(loc->dir, path, sizeof(loc->dir));
318 	} else {
319 		char	*tmp;
320 
321 		tmp = absolutify_path(*argv);
322 		strlcpy(loc->dir, tmp, sizeof(loc->dir));
323 		free(tmp);
324 	}
325 
326 	/* start the server */
327 	signal(SIGPIPE, SIG_IGN);
328 	setproctitle("%s", loc->dir);
329 	return serve(conf, hostname, port, loc->dir);
330 }