1 /*
2 * Copyright (c) 1980, 1993
3 * The Regents of the University of California. 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 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30 #include <sys/types.h>
31 #include <sys/socket.h>
32
33 #include <netinet/in.h>
34
35 #include <alloca.h>
36 #include <stdio.h>
37 #include <netdb.h>
38 #include <errno.h>
39 #include <stdlib.h>
40 #include <string.h>
41 #include <unistd.h>
42 #include <sys/uio.h>
43 #include <set-freeres.h>
44
45 int rexecoptions;
46 static char *ahostbuf;
47
48 int
49 rexec_af (char **ahost, int rport, const char *name, const char *pass,
50 const char *cmd, int *fd2p, sa_family_t af)
51 {
52 struct sockaddr_storage from;
53 struct addrinfo hints, *res0;
54 const char *orig_name = name;
55 const char *orig_pass = pass;
56 u_short port = 0;
57 int s, timo = 1, s3;
58 char c;
59 int gai;
60 char servbuff[NI_MAXSERV];
61
62 __snprintf(servbuff, sizeof(servbuff), "%d", ntohs(rport));
63 servbuff[sizeof(servbuff) - 1] = '\0';
64
65 memset(&hints, '\0', sizeof(hints));
66 hints.ai_family = af;
67 hints.ai_socktype = SOCK_STREAM;
68 hints.ai_flags = AI_CANONNAME;
69 gai = getaddrinfo(*ahost, servbuff, &hints, &res0);
70 if (gai){
71 /* XXX: set errno? */
72 return -1;
73 }
74
75 if (res0->ai_canonname){
76 free (ahostbuf);
77 ahostbuf = __strdup (res0->ai_canonname);
78 if (ahostbuf == NULL) {
79 perror ("rexec: strdup");
80 goto bad2;
81 }
82 *ahost = ahostbuf;
83 } else {
84 *ahost = NULL;
85 __set_errno (ENOENT);
86 goto bad2;
87 }
88 ruserpass(res0->ai_canonname, &name, &pass);
89 retry:
90 /* NB: No SOCK_CLOEXEC for backwards compatibility. */
91 s = __socket(res0->ai_family, res0->ai_socktype, 0);
92 if (s < 0) {
93 perror("rexec: socket");
94 goto bad2;
95 }
96 if (__connect(s, res0->ai_addr, res0->ai_addrlen) < 0) {
97 if (errno == ECONNREFUSED && timo <= 16) {
98 (void) __close(s);
99 __sleep(timo);
100 timo *= 2;
101 goto retry;
102 }
103 perror(res0->ai_canonname);
104 goto bad;
105 }
106 if (fd2p == 0) {
107 (void) __write(s, "", 1);
108 port = 0;
109 } else {
110 char num[32];
111 int s2;
112 union
113 {
114 struct sockaddr_storage ss;
115 struct sockaddr sa;
116 } sa2;
117 socklen_t sa2len;
118
119 s2 = __socket(res0->ai_family, res0->ai_socktype, 0);
120 if (s2 < 0)
121 goto bad;
122
123 __listen(s2, 1);
124 sa2len = sizeof (sa2);
125 if (__getsockname(s2, &sa2.sa, &sa2len) < 0) {
126 perror("getsockname");
127 (void) __close(s2);
128 goto bad;
129 } else if (sa2len != SA_LEN(&sa2.sa)) {
130 __set_errno(EINVAL);
131 (void) __close(s2);
132 goto bad;
133 }
134 port = 0;
135 if (!getnameinfo(&sa2.sa, sa2len,
136 NULL, 0, servbuff, sizeof(servbuff),
137 NI_NUMERICSERV))
138 port = strtol(servbuff, NULL, 10);
139 (void) sprintf(num, "%u", port);
140 (void) __write(s, num, strlen(num)+1);
141 { socklen_t len = sizeof (from);
142 s3 = TEMP_FAILURE_RETRY (accept(s2, (struct sockaddr *)&from,
143 &len));
144 __close(s2);
145 if (s3 < 0) {
146 perror("accept");
147 port = 0;
148 goto bad;
149 }
150 }
151 *fd2p = s3;
152 }
153
154 struct iovec iov[3] =
155 {
156 [0] = { .iov_base = (void *) name, .iov_len = strlen (name) + 1 },
157 /* should public key encrypt the password here */
158 [1] = { .iov_base = (void *) pass, .iov_len = strlen (pass) + 1 },
159 [2] = { .iov_base = (void *) cmd, .iov_len = strlen (cmd) + 1 }
160 };
161 (void) TEMP_FAILURE_RETRY (__writev (s, iov, 3));
162
163 /* We don't need the memory allocated for the name and the password
164 in ruserpass anymore. */
165 if (name != orig_name)
166 free ((char *) name);
167 if (pass != orig_pass)
168 free ((char *) pass);
169
170 if (__read(s, &c, 1) != 1) {
171 perror(*ahost);
172 goto bad;
173 }
174 if (c != 0) {
175 while (__read(s, &c, 1) == 1) {
176 (void) __write(2, &c, 1);
177 if (c == '\n')
178 break;
179 }
180 goto bad;
181 }
182 freeaddrinfo(res0);
183 return (s);
184 bad:
185 if (port)
186 (void) __close(*fd2p);
187 (void) __close(s);
188 bad2:
189 freeaddrinfo(res0);
190 return (-1);
191 }
192 libc_hidden_def (rexec_af)
193
194 int
195 rexec (char **ahost, int rport, const char *name, const char *pass,
196 const char *cmd, int *fd2p)
197 {
198 return rexec_af(ahost, rport, name, pass, cmd, fd2p, AF_INET);
199 }
200
201 weak_alias (ahostbuf, __libc_rexec_freemem_ptr)