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) |
202 | |