xref: /freebsd/contrib/lib9p/transport/socket.c (revision 3078531de10dcae44b253a35125c949ff4235284)
1 /*
2  * Copyright 2016 Jakub Klama <jceel@FreeBSD.org>
3  * All rights reserved
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted providing that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
16  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
18  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
22  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
23  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
24  * POSSIBILITY OF SUCH DAMAGE.
25  *
26  */
27 
28 #include <stdlib.h>
29 #include <errno.h>
30 #include <string.h>
31 #include <unistd.h>
32 #include <pthread.h>
33 #include <assert.h>
34 #include <sys/types.h>
35 #ifdef __APPLE__
36 # include "../apple_endian.h"
37 #else
38 # include <sys/endian.h>
39 #endif
40 #include <sys/socket.h>
41 #include <sys/event.h>
42 #include <sys/uio.h>
43 #include <netdb.h>
44 #include "../lib9p.h"
45 #include "../lib9p_impl.h"
46 #include "../log.h"
47 #include "socket.h"
48 
49 struct l9p_socket_softc
50 {
51 	struct l9p_connection *ls_conn;
52 	struct sockaddr ls_sockaddr;
53 	socklen_t ls_socklen;
54 	pthread_t ls_thread;
55 	int ls_fd;
56 };
57 
58 static int l9p_socket_readmsg(struct l9p_socket_softc *, void **, size_t *);
59 static int l9p_socket_get_response_buffer(struct l9p_request *,
60     struct iovec *, size_t *, void *);
61 static int l9p_socket_send_response(struct l9p_request *, const struct iovec *,
62     const size_t, const size_t, void *);
63 static void l9p_socket_drop_response(struct l9p_request *, const struct iovec *,
64     size_t, void *);
65 static void *l9p_socket_thread(void *);
66 static ssize_t xread(int, void *, size_t);
67 static ssize_t xwrite(int, void *, size_t);
68 
69 int
70 l9p_start_server(struct l9p_server *server, const char *host, const char *port)
71 {
72 	struct addrinfo *res, *res0, hints;
73 	struct kevent kev[2];
74 	struct kevent event[2];
75 	int err, kq, i, val, evs, nsockets = 0;
76 	int sockets[2];
77 
78 	memset(&hints, 0, sizeof(hints));
79 	hints.ai_family = PF_UNSPEC;
80 	hints.ai_socktype = SOCK_STREAM;
81 	err = getaddrinfo(host, port, &hints, &res0);
82 
83 	if (err)
84 		return (-1);
85 
86 	for (res = res0; res; res = res->ai_next) {
87 		int s = socket(res->ai_family, res->ai_socktype,
88 		    res->ai_protocol);
89 
90 		val = 1;
91 		setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
92 
93 		if (s < 0)
94 			continue;
95 
96 		if (bind(s, res->ai_addr, res->ai_addrlen) < 0) {
97 			close(s);
98 			continue;
99 		}
100 
101 		sockets[nsockets] = s;
102 		EV_SET(&kev[nsockets++], s, EVFILT_READ, EV_ADD | EV_ENABLE, 0,
103 		    0, 0);
104 		listen(s, 10);
105 	}
106 
107 	if (nsockets < 1) {
108 		L9P_LOG(L9P_ERROR, "bind(): %s", strerror(errno));
109 		return(-1);
110 	}
111 
112 	kq = kqueue();
113 
114 	if (kevent(kq, kev, nsockets, NULL, 0, NULL) < 0) {
115 		L9P_LOG(L9P_ERROR, "kevent(): %s", strerror(errno));
116 		return (-1);
117 	}
118 
119 	for (;;) {
120 		evs = kevent(kq, NULL, 0, event, nsockets, NULL);
121 		if (evs < 0) {
122 			if (errno == EINTR)
123 				continue;
124 
125 			L9P_LOG(L9P_ERROR, "kevent(): %s", strerror(errno));
126 			return (-1);
127 		}
128 
129 		for (i = 0; i < evs; i++) {
130 			struct sockaddr client_addr;
131 			socklen_t client_addr_len = sizeof(client_addr);
132 			int news = accept((int)event[i].ident, &client_addr,
133 			    &client_addr_len);
134 
135 			if (news < 0) {
136 				L9P_LOG(L9P_WARNING, "accept(): %s",
137 				    strerror(errno));
138 				continue;
139 			}
140 
141 			l9p_socket_accept(server, news, &client_addr,
142 			    client_addr_len);
143 		}
144 	}
145 
146 }
147 
148 void
149 l9p_socket_accept(struct l9p_server *server, int conn_fd,
150     struct sockaddr *client_addr, socklen_t client_addr_len)
151 {
152 	struct l9p_socket_softc *sc;
153 	struct l9p_connection *conn;
154 	char host[NI_MAXHOST + 1];
155 	char serv[NI_MAXSERV + 1];
156 	int err;
157 
158 	err = getnameinfo(client_addr, client_addr_len, host, NI_MAXHOST, serv,
159 	    NI_MAXSERV, NI_NUMERICHOST | NI_NUMERICSERV);
160 
161 	if (err != 0) {
162 		L9P_LOG(L9P_WARNING, "cannot look up client name: %s",
163 		    gai_strerror(err));
164 	} else {
165 		L9P_LOG(L9P_INFO, "new connection from %s:%s", host, serv);
166 	}
167 
168 	if (l9p_connection_init(server, &conn) != 0) {
169 		L9P_LOG(L9P_ERROR, "cannot create new connection");
170 		return;
171 	}
172 
173 	sc = l9p_calloc(1, sizeof(*sc));
174 	sc->ls_conn = conn;
175 	sc->ls_fd = conn_fd;
176 
177 	/*
178 	 * Fill in transport handler functions and aux argument.
179 	 */
180 	conn->lc_lt.lt_aux = sc;
181 	conn->lc_lt.lt_get_response_buffer = l9p_socket_get_response_buffer;
182 	conn->lc_lt.lt_send_response = l9p_socket_send_response;
183 	conn->lc_lt.lt_drop_response = l9p_socket_drop_response;
184 
185 	err = pthread_create(&sc->ls_thread, NULL, l9p_socket_thread, sc);
186 	if (err) {
187 		L9P_LOG(L9P_ERROR,
188 		    "pthread_create (for connection from %s:%s): error %s",
189 		    host, serv, strerror(err));
190 		l9p_connection_close(sc->ls_conn);
191 		free(sc);
192 	}
193 }
194 
195 static void *
196 l9p_socket_thread(void *arg)
197 {
198 	struct l9p_socket_softc *sc = (struct l9p_socket_softc *)arg;
199 	struct iovec iov;
200 	void *buf;
201 	size_t length;
202 
203 	for (;;) {
204 		if (l9p_socket_readmsg(sc, &buf, &length) != 0)
205 			break;
206 
207 		iov.iov_base = buf;
208 		iov.iov_len = length;
209 		l9p_connection_recv(sc->ls_conn, &iov, 1, NULL);
210 		free(buf);
211 	}
212 
213 	L9P_LOG(L9P_INFO, "connection closed");
214 	l9p_connection_close(sc->ls_conn);
215 	free(sc);
216 	return (NULL);
217 }
218 
219 static int
220 l9p_socket_readmsg(struct l9p_socket_softc *sc, void **buf, size_t *size)
221 {
222 	uint32_t msize;
223 	size_t toread;
224 	ssize_t ret;
225 	void *buffer;
226 	int fd = sc->ls_fd;
227 
228 	assert(fd > 0);
229 
230 	buffer = l9p_malloc(sizeof(uint32_t));
231 
232 	ret = xread(fd, buffer, sizeof(uint32_t));
233 	if (ret < 0) {
234 		L9P_LOG(L9P_ERROR, "read(): %s", strerror(errno));
235 		return (-1);
236 	}
237 
238 	if (ret != sizeof(uint32_t)) {
239 		if (ret == 0)
240 			L9P_LOG(L9P_DEBUG, "%p: EOF", (void *)sc->ls_conn);
241 		else
242 			L9P_LOG(L9P_ERROR,
243 			    "short read: %zd bytes of %zd expected",
244 			    ret, sizeof(uint32_t));
245 		return (-1);
246 	}
247 
248 	msize = le32toh(*(uint32_t *)buffer);
249 	toread = msize - sizeof(uint32_t);
250 	buffer = l9p_realloc(buffer, msize);
251 
252 	ret = xread(fd, (char *)buffer + sizeof(uint32_t), toread);
253 	if (ret < 0) {
254 		L9P_LOG(L9P_ERROR, "read(): %s", strerror(errno));
255 		return (-1);
256 	}
257 
258 	if (ret != (ssize_t)toread) {
259 		L9P_LOG(L9P_ERROR, "short read: %zd bytes of %zd expected",
260 		    ret, toread);
261 		return (-1);
262 	}
263 
264 	*size = msize;
265 	*buf = buffer;
266 	L9P_LOG(L9P_INFO, "%p: read complete message, buf=%p size=%d",
267 	    (void *)sc->ls_conn, buffer, msize);
268 
269 	return (0);
270 }
271 
272 static int
273 l9p_socket_get_response_buffer(struct l9p_request *req, struct iovec *iov,
274     size_t *niovp, void *arg __unused)
275 {
276 	size_t size = req->lr_conn->lc_msize;
277 	void *buf;
278 
279 	buf = l9p_malloc(size);
280 	iov[0].iov_base = buf;
281 	iov[0].iov_len = size;
282 
283 	*niovp = 1;
284 	return (0);
285 }
286 
287 static int
288 l9p_socket_send_response(struct l9p_request *req __unused,
289     const struct iovec *iov, const size_t niov __unused, const size_t iolen,
290     void *arg)
291 {
292 	struct l9p_socket_softc *sc = (struct l9p_socket_softc *)arg;
293 
294 	assert(sc->ls_fd >= 0);
295 
296 	L9P_LOG(L9P_DEBUG, "%p: sending reply, buf=%p, size=%d", arg,
297 	    iov[0].iov_base, iolen);
298 
299 	if (xwrite(sc->ls_fd, iov[0].iov_base, iolen) != (int)iolen) {
300 		L9P_LOG(L9P_ERROR, "short write: %s", strerror(errno));
301 		return (-1);
302 	}
303 
304 	free(iov[0].iov_base);
305 	return (0);
306 }
307 
308 static void
309 l9p_socket_drop_response(struct l9p_request *req __unused,
310     const struct iovec *iov, size_t niov __unused, void *arg __unused)
311 {
312 
313 	L9P_LOG(L9P_DEBUG, "%p: drop buf=%p", arg, iov[0].iov_base);
314 	free(iov[0].iov_base);
315 }
316 
317 static ssize_t
318 xread(int fd, void *buf, size_t count)
319 {
320 	size_t done = 0;
321 	ssize_t ret;
322 
323 	while (done < count) {
324 		ret = read(fd, (char *)buf + done, count - done);
325 		if (ret < 0) {
326 			if (errno == EINTR)
327 				continue;
328 
329 			return (-1);
330 		}
331 
332 		if (ret == 0)
333 			return ((ssize_t)done);
334 
335 		done += (size_t)ret;
336 	}
337 
338 	return ((ssize_t)done);
339 }
340 
341 static ssize_t
342 xwrite(int fd, void *buf, size_t count)
343 {
344 	size_t done = 0;
345 	ssize_t ret;
346 
347 	while (done < count) {
348 		ret = write(fd, (char *)buf + done, count - done);
349 		if (ret < 0) {
350 			if (errno == EINTR)
351 				continue;
352 
353 			return (-1);
354 		}
355 
356 		if (ret == 0)
357 			return ((ssize_t)done);
358 
359 		done += (size_t)ret;
360 	}
361 
362 	return ((ssize_t)done);
363 }
364