xref: /freebsd/usr.sbin/nscd/nscdcli.c (revision ea906c4152774dff300bb26fbfc1e4188351c89a)
1 /*-
2  * Copyright (c) 2005 Michael Bushkov <bushman@rsu.ru>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided 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 AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY 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, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/types.h>
32 #include <sys/socket.h>
33 #include <sys/event.h>
34 #include <sys/uio.h>
35 #include <sys/un.h>
36 #include <assert.h>
37 #include <errno.h>
38 #include <fcntl.h>
39 #include <stdlib.h>
40 #include <string.h>
41 #include <unistd.h>
42 
43 #include "debug.h"
44 #include "nscdcli.h"
45 #include "protocol.h"
46 
47 #define DEFAULT_NSCD_IO_TIMEOUT	4
48 
49 static int safe_write(struct nscd_connection_ *, const void *, size_t);
50 static int safe_read(struct nscd_connection_ *, void *, size_t);
51 static int send_credentials(struct nscd_connection_ *, int);
52 
53 static int
54 safe_write(struct nscd_connection_ *connection, const void *data,
55 	size_t data_size)
56 {
57 	struct kevent eventlist;
58 	int	nevents;
59 	size_t result;
60 	ssize_t s_result;
61 	struct timespec	timeout;
62 
63 	if (data_size == 0)
64 		return (0);
65 
66 	timeout.tv_sec = DEFAULT_NSCD_IO_TIMEOUT;
67 	timeout.tv_nsec = 0;
68 	result = 0;
69 	do {
70 		nevents = kevent(connection->write_queue, NULL, 0, &eventlist,
71 	    		1, &timeout);
72 		if ((nevents == 1) && (eventlist.filter == EVFILT_WRITE)) {
73 			s_result = write(connection->sockfd, data + result,
74 				eventlist.data < data_size - result ?
75 		    		eventlist.data : data_size - result);
76 			if (s_result == -1)
77 				return (-1);
78 			else
79 				result += s_result;
80 
81 			if (eventlist.flags & EV_EOF)
82 				return (result < data_size ? -1 : 0);
83 		} else
84 			return (-1);
85 	} while (result < data_size);
86 
87 	return (0);
88 }
89 
90 static int
91 safe_read(struct nscd_connection_ *connection, void *data, size_t data_size)
92 {
93 	struct kevent eventlist;
94 	size_t result;
95 	ssize_t s_result;
96 	struct timespec timeout;
97 	int nevents;
98 
99 	if (data_size == 0)
100 		return (0);
101 
102 	timeout.tv_sec = DEFAULT_NSCD_IO_TIMEOUT;
103 	timeout.tv_nsec = 0;
104 	result = 0;
105 	do {
106 		nevents = kevent(connection->read_queue, NULL, 0, &eventlist, 1,
107 			&timeout);
108 		if ((nevents == 1) && (eventlist.filter == EVFILT_READ)) {
109 			s_result = read(connection->sockfd, data + result,
110 			eventlist.data <= data_size - result ? eventlist.data :
111 				data_size - result);
112 			if (s_result == -1)
113 				return (-1);
114 			else
115 				result += s_result;
116 
117 			if (eventlist.flags & EV_EOF)
118 				return (result < data_size ? -1 : 0);
119 		} else
120 			return (-1);
121 	} while (result < data_size);
122 
123 	return (0);
124 }
125 
126 static int
127 send_credentials(struct nscd_connection_ *connection, int type)
128 {
129 	struct kevent eventlist;
130 	int nevents;
131 	ssize_t result;
132 	int res;
133 
134 	struct msghdr	cred_hdr;
135 	struct iovec	iov;
136 
137 	struct {
138 		struct cmsghdr	hdr;
139 		struct cmsgcred	creds;
140 	} cmsg;
141 
142 	TRACE_IN(send_credentials);
143 	memset(&cmsg, 0, sizeof(cmsg));
144 	cmsg.hdr.cmsg_len = sizeof(cmsg);
145 	cmsg.hdr.cmsg_level = SOL_SOCKET;
146 	cmsg.hdr.cmsg_type = SCM_CREDS;
147 
148 	memset(&cred_hdr, 0, sizeof(struct msghdr));
149 	cred_hdr.msg_iov = &iov;
150 	cred_hdr.msg_iovlen = 1;
151 	cred_hdr.msg_control = &cmsg;
152 	cred_hdr.msg_controllen = sizeof(cmsg);
153 
154 	iov.iov_base = &type;
155 	iov.iov_len = sizeof(int);
156 
157 	EV_SET(&eventlist, connection->sockfd, EVFILT_WRITE, EV_ADD,
158 		NOTE_LOWAT, sizeof(int), NULL);
159 	res = kevent(connection->write_queue, &eventlist, 1, NULL, 0, NULL);
160 
161 	nevents = kevent(connection->write_queue, NULL, 0, &eventlist, 1, NULL);
162 	if ((nevents == 1) && (eventlist.filter == EVFILT_WRITE)) {
163 		result = (sendmsg(connection->sockfd, &cred_hdr, 0) == -1) ? -1
164 	    		: 0;
165 		EV_SET(&eventlist, connection->sockfd, EVFILT_WRITE, EV_ADD,
166 			0, 0, NULL);
167 		kevent(connection->write_queue, &eventlist, 1, NULL, 0, NULL);
168 		TRACE_OUT(send_credentials);
169 		return (result);
170 	} else {
171 		TRACE_OUT(send_credentials);
172 		return (-1);
173 	}
174 }
175 
176 struct nscd_connection_ *
177 open_nscd_connection__(struct nscd_connection_params const *params)
178 {
179 	struct nscd_connection_ *retval;
180 	struct kevent eventlist;
181 	struct sockaddr_un	client_address;
182 	int client_address_len, client_socket;
183 	int res;
184 
185 	TRACE_IN(open_nscd_connection);
186 	assert(params != NULL);
187 
188 	client_socket = socket(PF_LOCAL, SOCK_STREAM, 0);
189 	client_address.sun_family = PF_LOCAL;
190 	strncpy(client_address.sun_path, params->socket_path,
191 		sizeof(client_address.sun_path));
192 	client_address_len = sizeof(client_address.sun_family) +
193 		strlen(client_address.sun_path) + 1;
194 
195 	res = connect(client_socket, (struct sockaddr *)&client_address,
196 		client_address_len);
197 	if (res == -1) {
198 		close(client_socket);
199 		TRACE_OUT(open_nscd_connection);
200 		return (NULL);
201 	}
202 	fcntl(client_socket, F_SETFL, O_NONBLOCK);
203 
204 	retval = malloc(sizeof(struct nscd_connection_));
205 	assert(retval != NULL);
206 	memset(retval, 0, sizeof(struct nscd_connection_));
207 
208 	retval->sockfd = client_socket;
209 
210 	retval->write_queue = kqueue();
211 	assert(retval->write_queue != -1);
212 
213 	EV_SET(&eventlist, retval->sockfd, EVFILT_WRITE, EV_ADD,
214 		0, 0, NULL);
215 	res = kevent(retval->write_queue, &eventlist, 1, NULL, 0, NULL);
216 
217 	retval->read_queue = kqueue();
218 	assert(retval->read_queue != -1);
219 
220 	EV_SET(&eventlist, retval->sockfd, EVFILT_READ, EV_ADD,
221 		0, 0, NULL);
222 	res = kevent(retval->read_queue, &eventlist, 1, NULL, 0, NULL);
223 
224 	TRACE_OUT(open_nscd_connection);
225 	return (retval);
226 }
227 
228 void
229 close_nscd_connection__(struct nscd_connection_ *connection)
230 {
231 
232 	TRACE_IN(close_nscd_connection);
233 	assert(connection != NULL);
234 
235 	close(connection->sockfd);
236 	close(connection->read_queue);
237 	close(connection->write_queue);
238 	free(connection);
239 	TRACE_OUT(close_nscd_connection);
240 }
241 
242 int
243 nscd_transform__(struct nscd_connection_ *connection,
244 	const char *entry_name, int transformation_type)
245 {
246 	size_t name_size;
247 	int error_code;
248 	int result;
249 
250 	TRACE_IN(nscd_transform);
251 
252 	error_code = -1;
253 	result = 0;
254 	result = send_credentials(connection, CET_TRANSFORM_REQUEST);
255 	if (result != 0)
256 		goto fin;
257 
258 	if (entry_name != NULL)
259 		name_size = strlen(entry_name);
260 	else
261 		name_size = 0;
262 
263 	result = safe_write(connection, &name_size, sizeof(size_t));
264 	if (result != 0)
265 		goto fin;
266 
267 	result = safe_write(connection, &transformation_type, sizeof(int));
268 	if (result != 0)
269 		goto fin;
270 
271 	if (entry_name != NULL) {
272 		result = safe_write(connection, entry_name, name_size);
273 		if (result != 0)
274 			goto fin;
275 	}
276 
277 	result = safe_read(connection, &error_code, sizeof(int));
278 	if (result != 0)
279 		error_code = -1;
280 
281 fin:
282 	TRACE_OUT(nscd_transform);
283 	return (error_code);
284 }
285