xref: /freebsd/lib/libc/rpc/getpublickey.c (revision 397e83df75e0fcd0d3fcb95ae4d794cb7600fc89)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 2009, Sun Microsystems, Inc.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions are met:
9  * - Redistributions of source code must retain the above copyright notice,
10  *   this list of conditions and the following disclaimer.
11  * - Redistributions in binary form must reproduce the above copyright notice,
12  *   this list of conditions and the following disclaimer in the documentation
13  *   and/or other materials provided with the distribution.
14  * - Neither the name of Sun Microsystems, Inc. nor the names of its
15  *   contributors may be used to endorse or promote products derived
16  *   from this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
22  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28  * POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 /*
32  * publickey.c
33  * Copyright (C) 1986, Sun Microsystems, Inc.
34  */
35 
36 /*
37  * Public key lookup routines
38  */
39 #include "namespace.h"
40 #include <stdio.h>
41 #include <pwd.h>
42 #include <rpc/rpc.h>
43 #include <rpc/key_prot.h>
44 #include <rpcsvc/yp_prot.h>
45 #include <rpcsvc/ypclnt.h>
46 #include <string.h>
47 #include <stdlib.h>
48 #include "un-namespace.h"
49 
50 #define PKFILE "/etc/publickey"
51 
52 /*
53  * Hack to let ypserv/rpc.nisd use AUTH_DES.
54  */
55 int (*__getpublickey_LOCAL)(const char *, char *) = 0;
56 
57 /*
58  * Get somebody's public key
59  */
60 static int
61 __getpublickey_real(const char *netname, char *publickey)
62 {
63 	char lookup[3 * HEXKEYBYTES];
64 	char *p;
65 
66 	if (publickey == NULL)
67 		return (0);
68 	if (!getpublicandprivatekey(netname, lookup))
69 		return (0);
70 	p = strchr(lookup, ':');
71 	if (p == NULL) {
72 		return (0);
73 	}
74 	*p = '\0';
75 	(void) strncpy(publickey, lookup, HEXKEYBYTES);
76 	publickey[HEXKEYBYTES] = '\0';
77 	return (1);
78 }
79 
80 /*
81  * reads the file /etc/publickey looking for a + to optionally go to the
82  * yellow pages
83  */
84 
85 int
86 getpublicandprivatekey(const char *key, char *ret)
87 {
88 	char buf[1024];	/* big enough */
89 	char *res;
90 	FILE *fd;
91 	char *mkey;
92 	char *mval;
93 
94 	fd = fopen(PKFILE, "r");
95 	if (fd == NULL)
96 		return (0);
97 	for (;;) {
98 		res = fgets(buf, sizeof(buf), fd);
99 		if (res == NULL) {
100 			fclose(fd);
101 			return (0);
102 		}
103 		if (res[0] == '#')
104 			continue;
105 		else if (res[0] == '+') {
106 #ifdef YP
107 			char *PKMAP = "publickey.byname";
108 			char *lookup;
109 			char *domain;
110 			int err;
111 			int len;
112 
113 			err = yp_get_default_domain(&domain);
114 			if (err) {
115 				continue;
116 			}
117 			lookup = NULL;
118 			err = yp_match(domain, PKMAP, key, strlen(key), &lookup, &len);
119 			if (err) {
120 #ifdef DEBUG
121 				fprintf(stderr, "match failed error %d\n", err);
122 #endif
123 				continue;
124 			}
125 			lookup[len] = 0;
126 			strcpy(ret, lookup);
127 			fclose(fd);
128 			free(lookup);
129 			return (2);
130 #else /* YP */
131 #ifdef DEBUG
132 			fprintf(stderr,
133 "Bad record in %s '+' -- NIS not supported in this library copy\n", PKFILE);
134 #endif /* DEBUG */
135 			continue;
136 #endif /* YP */
137 		} else {
138 			mkey = strsep(&res, "\t ");
139 			if (mkey == NULL) {
140 				fprintf(stderr,
141 				"Bad record in %s -- %s", PKFILE, buf);
142 				continue;
143 			}
144 			do {
145 				mval = strsep(&res, " \t#\n");
146 			} while (mval != NULL && !*mval);
147 			if (mval == NULL) {
148 				fprintf(stderr,
149 			"Bad record in %s val problem - %s", PKFILE, buf);
150 				continue;
151 			}
152 			if (strcmp(mkey, key) == 0) {
153 				strcpy(ret, mval);
154 				fclose(fd);
155 				return (1);
156 			}
157 		}
158 	}
159 }
160 
161 int getpublickey(const char *netname, char *publickey)
162 {
163 	if (__getpublickey_LOCAL != NULL)
164 		return(__getpublickey_LOCAL(netname, publickey));
165 	else
166 		return(__getpublickey_real(netname, publickey));
167 }
168