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