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
44int rexecoptions;
45libc_freeres_ptr (static char *ahostbuf);
46
47int
48rexec_af (char **ahost, int rport, const char *name, const char *pass,
49 const char *cmd, int *fd2p, sa_family_t af)
50{
51 struct sockaddr_storage from;
52 struct addrinfo hints, *res0;
53 const char *orig_name = name;
54 const char *orig_pass = pass;
55 u_short port = 0;
56 int s, timo = 1, s3;
57 char c;
58 int gai;
59 char servbuff[NI_MAXSERV];
60
61 __snprintf(servbuff, sizeof(servbuff), "%d", ntohs(rport));
62 servbuff[sizeof(servbuff) - 1] = '\0';
63
64 memset(&hints, '\0', sizeof(hints));
65 hints.ai_family = af;
66 hints.ai_socktype = SOCK_STREAM;
67 hints.ai_flags = AI_CANONNAME;
68 gai = getaddrinfo(*ahost, servbuff, &hints, &res0);
69 if (gai){
70 /* XXX: set errno? */
71 return -1;
72 }
73
74 if (res0->ai_canonname){
75 free (ahostbuf);
76 ahostbuf = __strdup (res0->ai_canonname);
77 if (ahostbuf == NULL) {
78 perror ("rexec: strdup");
79 goto bad2;
80 }
81 *ahost = ahostbuf;
82 } else {
83 *ahost = NULL;
84 __set_errno (ENOENT);
85 goto bad2;
86 }
87 ruserpass(res0->ai_canonname, &name, &pass);
88retry:
89 /* NB: No SOCK_CLOEXEC for backwards compatibility. */
90 s = __socket(res0->ai_family, res0->ai_socktype, 0);
91 if (s < 0) {
92 perror("rexec: socket");
93 goto bad2;
94 }
95 if (__connect(s, res0->ai_addr, res0->ai_addrlen) < 0) {
96 if (errno == ECONNREFUSED && timo <= 16) {
97 (void) __close(s);
98 __sleep(timo);
99 timo *= 2;
100 goto retry;
101 }
102 perror(res0->ai_canonname);
103 goto bad;
104 }
105 if (fd2p == 0) {
106 (void) __write(s, "", 1);
107 port = 0;
108 } else {
109 char num[32];
110 int s2;
111 union
112 {
113 struct sockaddr_storage ss;
114 struct sockaddr sa;
115 } sa2;
116 socklen_t sa2len;
117
118 s2 = __socket(res0->ai_family, res0->ai_socktype, 0);
119 if (s2 < 0)
120 goto bad;
121
122 __listen(s2, 1);
123 sa2len = sizeof (sa2);
124 if (__getsockname(s2, &sa2.sa, &sa2len) < 0) {
125 perror("getsockname");
126 (void) __close(s2);
127 goto bad;
128 } else if (sa2len != SA_LEN(&sa2.sa)) {
129 __set_errno(EINVAL);
130 (void) __close(s2);
131 goto bad;
132 }
133 port = 0;
134 if (!getnameinfo(&sa2.sa, sa2len,
135 NULL, 0, servbuff, sizeof(servbuff),
136 NI_NUMERICSERV))
137 port = atoi(servbuff);
138 (void) sprintf(num, "%u", port);
139 (void) __write(s, num, strlen(num)+1);
140 { socklen_t len = sizeof (from);
141 s3 = TEMP_FAILURE_RETRY (accept(s2, (struct sockaddr *)&from,
142 &len));
143 __close(s2);
144 if (s3 < 0) {
145 perror("accept");
146 port = 0;
147 goto bad;
148 }
149 }
150 *fd2p = s3;
151 }
152
153 struct iovec iov[3] =
154 {
155 [0] = { .iov_base = (void *) name, .iov_len = strlen (name) + 1 },
156 /* should public key encypt the password here */
157 [1] = { .iov_base = (void *) pass, .iov_len = strlen (pass) + 1 },
158 [2] = { .iov_base = (void *) cmd, .iov_len = strlen (cmd) + 1 }
159 };
160 (void) TEMP_FAILURE_RETRY (__writev (s, iov, 3));
161
162 /* We don't need the memory allocated for the name and the password
163 in ruserpass anymore. */
164 if (name != orig_name)
165 free ((char *) name);
166 if (pass != orig_pass)
167 free ((char *) pass);
168
169 if (__read(s, &c, 1) != 1) {
170 perror(*ahost);
171 goto bad;
172 }
173 if (c != 0) {
174 while (__read(s, &c, 1) == 1) {
175 (void) __write(2, &c, 1);
176 if (c == '\n')
177 break;
178 }
179 goto bad;
180 }
181 freeaddrinfo(res0);
182 return (s);
183bad:
184 if (port)
185 (void) __close(*fd2p);
186 (void) __close(s);
187bad2:
188 freeaddrinfo(res0);
189 return (-1);
190}
191libc_hidden_def (rexec_af)
192
193int
194rexec (char **ahost, int rport, const char *name, const char *pass,
195 const char *cmd, int *fd2p)
196{
197 return rexec_af(ahost, rport, name, pass, cmd, fd2p, AF_INET);
198}
199