xref: /freebsd/usr.sbin/nscd/nscdcli.c (revision 1db64f89363c97858961c4df0b7d02f3223723cf)
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/types.h>
29 
30 #include <sys/event.h>
31 #include <sys/socket.h>
32 #include <sys/uio.h>
33 #include <sys/un.h>
34 
35 #include <assert.h>
36 #include <errno.h>
37 #include <fcntl.h>
38 #include <stdlib.h>
39 #include <string.h>
40 #include <unistd.h>
41 
42 #include "debug.h"
43 #include "nscdcli.h"
44 #include "protocol.h"
45 
46 #define DEFAULT_NSCD_IO_TIMEOUT	4
47 
48 static int safe_write(struct nscd_connection_ *, const void *, size_t);
49 static int safe_read(struct nscd_connection_ *, void *, size_t);
50 static int send_credentials(struct nscd_connection_ *, int);
51 
52 static int
53 safe_write(struct nscd_connection_ *connection, const void *data,
54 	size_t data_size)
55 {
56 	struct kevent eventlist;
57 	int	nevents;
58 	size_t result;
59 	ssize_t s_result;
60 	struct timespec	timeout;
61 
62 	if (data_size == 0)
63 		return (0);
64 
65 	timeout.tv_sec = DEFAULT_NSCD_IO_TIMEOUT;
66 	timeout.tv_nsec = 0;
67 	result = 0;
68 	do {
69 		nevents = kevent(connection->write_queue, NULL, 0, &eventlist,
70 	    		1, &timeout);
71 		if ((nevents == 1) && (eventlist.filter == EVFILT_WRITE)) {
72 			s_result = write(connection->sockfd,
73 				(char *)data + result,
74 				(size_t)eventlist.data < data_size - result ?
75 		    		(size_t)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,
110 				(char *)data + result,
111 				(size_t)eventlist.data <= data_size - result ?
112 				(size_t)eventlist.data : data_size - result);
113 			if (s_result == -1)
114 				return (-1);
115 			else
116 				result += s_result;
117 
118 			if (eventlist.flags & EV_EOF)
119 				return (result < data_size ? -1 : 0);
120 		} else
121 			return (-1);
122 	} while (result < data_size);
123 
124 	return (0);
125 }
126 
127 static int
128 send_credentials(struct nscd_connection_ *connection, int type)
129 {
130 	union {
131 		struct cmsghdr hdr;
132 		char pad[CMSG_SPACE(sizeof(struct cmsgcred))];
133 	} cmsg;
134 	struct msghdr mhdr;
135 	struct iovec iov;
136 	struct kevent eventlist;
137 	int nevents;
138 	ssize_t result;
139 
140 	TRACE_IN(send_credentials);
141 	memset(&cmsg, 0, sizeof(cmsg));
142 	cmsg.hdr.cmsg_len = CMSG_LEN(sizeof(struct cmsgcred));
143 	cmsg.hdr.cmsg_level = SOL_SOCKET;
144 	cmsg.hdr.cmsg_type = SCM_CREDS;
145 
146 	memset(&mhdr, 0, sizeof(mhdr));
147 	mhdr.msg_iov = &iov;
148 	mhdr.msg_iovlen = 1;
149 	mhdr.msg_control = &cmsg;
150 	mhdr.msg_controllen = CMSG_SPACE(sizeof(struct cmsgcred));
151 
152 	iov.iov_base = &type;
153 	iov.iov_len = sizeof(int);
154 
155 	EV_SET(&eventlist, connection->sockfd, EVFILT_WRITE, EV_ADD,
156 	    NOTE_LOWAT, sizeof(int), NULL);
157 	kevent(connection->write_queue, &eventlist, 1, NULL, 0, NULL);
158 
159 	nevents = kevent(connection->write_queue, NULL, 0, &eventlist, 1, NULL);
160 	if ((nevents == 1) && (eventlist.filter == EVFILT_WRITE)) {
161 		result = sendmsg(connection->sockfd, &mhdr, 0) == -1 ? -1 : 0;
162 		EV_SET(&eventlist, connection->sockfd, EVFILT_WRITE, EV_ADD,
163 		    0, 0, NULL);
164 		kevent(connection->write_queue, &eventlist, 1, NULL, 0, NULL);
165 		TRACE_OUT(send_credentials);
166 		return (result);
167 	} else {
168 		TRACE_OUT(send_credentials);
169 		return (-1);
170 	}
171 }
172 
173 struct nscd_connection_ *
174 open_nscd_connection__(struct nscd_connection_params const *params)
175 {
176 	struct nscd_connection_ *retval;
177 	struct kevent eventlist;
178 	struct sockaddr_un	client_address;
179 	int client_address_len, client_socket;
180 	int res;
181 
182 	TRACE_IN(open_nscd_connection);
183 	assert(params != NULL);
184 
185 	client_socket = socket(PF_LOCAL, SOCK_STREAM, 0);
186 	client_address.sun_family = PF_LOCAL;
187 	strlcpy(client_address.sun_path, params->socket_path,
188 		sizeof(client_address.sun_path));
189 	client_address_len = sizeof(client_address.sun_family) +
190 		strlen(client_address.sun_path) + 1;
191 
192 	res = connect(client_socket, (struct sockaddr *)&client_address,
193 		client_address_len);
194 	if (res == -1) {
195 		close(client_socket);
196 		TRACE_OUT(open_nscd_connection);
197 		return (NULL);
198 	}
199 	fcntl(client_socket, F_SETFL, O_NONBLOCK);
200 
201 	retval = calloc(1, sizeof(*retval));
202 	assert(retval != NULL);
203 
204 	retval->sockfd = client_socket;
205 
206 	retval->write_queue = kqueue();
207 	assert(retval->write_queue != -1);
208 
209 	EV_SET(&eventlist, retval->sockfd, EVFILT_WRITE, EV_ADD,
210 		0, 0, NULL);
211 	res = kevent(retval->write_queue, &eventlist, 1, NULL, 0, NULL);
212 
213 	retval->read_queue = kqueue();
214 	assert(retval->read_queue != -1);
215 
216 	EV_SET(&eventlist, retval->sockfd, EVFILT_READ, EV_ADD,
217 		0, 0, NULL);
218 	res = kevent(retval->read_queue, &eventlist, 1, NULL, 0, NULL);
219 
220 	TRACE_OUT(open_nscd_connection);
221 	return (retval);
222 }
223 
224 void
225 close_nscd_connection__(struct nscd_connection_ *connection)
226 {
227 
228 	TRACE_IN(close_nscd_connection);
229 	assert(connection != NULL);
230 
231 	close(connection->sockfd);
232 	close(connection->read_queue);
233 	close(connection->write_queue);
234 	free(connection);
235 	TRACE_OUT(close_nscd_connection);
236 }
237 
238 int
239 nscd_transform__(struct nscd_connection_ *connection,
240 	const char *entry_name, int transformation_type)
241 {
242 	size_t name_size;
243 	int error_code;
244 	int result;
245 
246 	TRACE_IN(nscd_transform);
247 
248 	error_code = -1;
249 	result = 0;
250 	result = send_credentials(connection, CET_TRANSFORM_REQUEST);
251 	if (result != 0)
252 		goto fin;
253 
254 	if (entry_name != NULL)
255 		name_size = strlen(entry_name);
256 	else
257 		name_size = 0;
258 
259 	result = safe_write(connection, &name_size, sizeof(size_t));
260 	if (result != 0)
261 		goto fin;
262 
263 	result = safe_write(connection, &transformation_type, sizeof(int));
264 	if (result != 0)
265 		goto fin;
266 
267 	if (entry_name != NULL) {
268 		result = safe_write(connection, entry_name, name_size);
269 		if (result != 0)
270 			goto fin;
271 	}
272 
273 	result = safe_read(connection, &error_code, sizeof(int));
274 	if (result != 0)
275 		error_code = -1;
276 
277 fin:
278 	TRACE_OUT(nscd_transform);
279 	return (error_code);
280 }
281