1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright (c) 1999 by Sun Microsystems, Inc.
24  * All rights reserved.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <sys/types.h>
30 #include <sys/socket.h>
31 #include <netinet/in.h>
32 #include <arpa/inet.h>
33 #include <stdlib.h>
34 #include <unistd.h>
35 #include <stdio.h>
36 #include <string.h>
37 #include <malloc.h>
38 #include <syslog.h>
39 #include <sys/tiuser.h>
40 
41 #define	ACCFILE "/var/yp/securenets"
42 #define	MAXLINE 128
43 
44 typedef union {
45 	struct in_addr	in4;
46 	struct in6_addr	in6;
47 } inaddr_t;
48 
49 struct seclist {
50 	sa_family_t	af;
51 	inaddr_t	mask;
52 	inaddr_t	net;
53 	struct seclist	*next;
54 };
55 
56 static int	string2inaddr(char *, sa_family_t *, inaddr_t *);
57 static int	addrequal(sa_family_t af, inaddr_t *laddr, inaddr_t *mask,
58 					inaddr_t *caddr);
59 
60 static struct seclist *slist;
61 static int nofile = 0;
62 
63 void
64 get_secure_nets(char *daemon_name)
65 {
66 	FILE *fp;
67 	char strung[MAXLINE], nmask[MAXLINE], net[MAXLINE];
68 	inaddr_t maskin, netin;
69 	sa_family_t maskaf, netaf;
70 	struct seclist *tmp1, *tmp2;
71 	int items = 0, line = 0;
72 	if (fp = fopen(ACCFILE, "r")) {
73 		tmp1 = (struct seclist *) malloc(sizeof (struct seclist));
74 		slist = tmp2 = tmp1;
75 		while (fgets(strung, MAXLINE, fp)) {
76 			line++;
77 			if (strung[strlen(strung) - 1] != '\n') {
78 				syslog(LOG_ERR|LOG_DAEMON,
79 					"%s: %s line %d: too long\n",
80 					daemon_name, ACCFILE, line);
81 				exit(1);
82 			}
83 			if (strung[0] != '#') {
84 				items++;
85 				if (sscanf(strung,
86 					"%46s%46s", nmask, net) < 2) {
87 
88 					syslog(LOG_ERR|LOG_DAEMON,
89 					"%s: %s line %d: missing fields\n",
90 						daemon_name, ACCFILE, line);
91 					exit(1);
92 				}
93 				netaf = AF_UNSPEC;
94 				if (! string2inaddr(net, &netaf, &netin)) {
95 					syslog(LOG_ERR|LOG_DAEMON,
96 					"%s: %s line %d: error in address\n",
97 						daemon_name, ACCFILE, line);
98 					exit(1);
99 				}
100 				maskaf = netaf;
101 				if (! string2inaddr(nmask, &maskaf, &maskin) ||
102 						maskaf != netaf) {
103 					syslog(LOG_ERR|LOG_DAEMON,
104 					"%s: %s line %d: error in netmask\n",
105 						daemon_name, ACCFILE, line);
106 					exit(1);
107 				}
108 				if (! addrequal(netaf, &netin, &maskin,
109 							&netin)) {
110 					syslog(LOG_ERR|LOG_DAEMON,
111 			"%s: %s line %d: netmask does not match network\n",
112 						daemon_name, ACCFILE, line);
113 					exit(1);
114 				}
115 
116 				tmp1->af = netaf;
117 				tmp1->mask = maskin;
118 				tmp1->net = netin;
119 				tmp1->next = (struct seclist *)
120 					malloc(sizeof (struct seclist));
121 				tmp2 = tmp1;
122 				tmp1 = tmp1->next;
123 			}
124 		}
125 		tmp2->next = NULL;
126 		/* if nothing to process, set nofile flag and free up memory */
127 		if (items == 0) {
128 			free(slist);
129 			nofile = 1;
130 		}
131 	} else {
132 		syslog(LOG_WARNING|LOG_DAEMON, "%s: no %s file\n",
133 			daemon_name, ACCFILE);
134 		nofile = 1;
135 	}
136 }
137 
138 int
139 check_secure_net_ti(struct netbuf *caller, char *ypname) {
140 	struct seclist *tmp;
141 	sa_family_t af;
142 	inaddr_t addr;
143 	char buf[INET6_ADDRSTRLEN];
144 
145 	if (nofile)
146 		return (1);
147 
148 	af = ((struct sockaddr_storage *)caller->buf)->ss_family;
149 	if (af == AF_INET) {
150 		addr.in4 = ((struct sockaddr_in *)caller->buf)->sin_addr;
151 	} else if (af == AF_INET6) {
152 		addr.in6 = ((struct sockaddr_in6 *)caller->buf)->sin6_addr;
153 	} else {
154 		return (1);
155 	}
156 
157 	tmp = slist;
158 	while (tmp != NULL) {
159 		if (af == tmp->af &&
160 			addrequal(af, &tmp->net, &tmp->mask, &addr)) {
161 			return (1);
162 		}
163 		tmp = tmp->next;
164 	}
165 	syslog(LOG_ERR|LOG_DAEMON, "%s: access denied for %s\n",
166 		ypname, inet_ntop(af,
167 			(af == AF_INET6) ? (void *)&addr.in6 :
168 				(void *)&addr.in4, buf, sizeof (buf)));
169 
170 	return (0);
171 }
172 
173 
174 static int
175 string2inaddr(char *string, sa_family_t *af, inaddr_t *addr) {
176 
177 	sa_family_t	stringaf = AF_UNSPEC;
178 
179 	stringaf = (strchr(string, ':') != 0) ?	AF_INET6 : AF_INET;
180 
181 	if (*af != AF_UNSPEC && strcmp(string, "host") == 0) {
182 		if (*af == AF_INET) {
183 			string = "255.255.255.255";
184 			stringaf = AF_INET;
185 		} else if (*af == AF_INET6) {
186 			string = "ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff";
187 			stringaf = AF_INET6;
188 		}
189 	}
190 
191 	*af = stringaf;
192 	if (inet_pton(*af, string, (*af == AF_INET6) ? (void *)&addr->in6 :
193 						(void *)&addr->in4) != 1) {
194 		return (0);
195 	}
196 
197 	return (1);
198 }
199 
200 
201 static int
202 addrequal(sa_family_t af, inaddr_t *laddr, inaddr_t *mask, inaddr_t *caddr) {
203 
204 	if (af == AF_INET6) {
205 		int i;
206 		for (i = 0; i < sizeof (laddr->in6.s6_addr); i++) {
207 			if ((caddr->in6.s6_addr[i] & mask->in6.s6_addr[i]) !=
208 					laddr->in6.s6_addr[i])
209 				return (0);
210 		}
211 		return (1);
212 	} else if (af == AF_INET) {
213 		return ((caddr->in4.s_addr & mask->in4.s_addr) ==
214 				laddr->in4.s_addr);
215 	} else {
216 		return (0);
217 	}
218 }
219 
220 
221 static void
222 print_inaddr(char *string, sa_family_t af, inaddr_t *addr) {
223 
224 	char buf[INET6_ADDRSTRLEN];
225 
226 	printf("%s %s %s\n",
227 		string, (af == AF_INET6)?"AF_INET6":"AF_INET",
228 		inet_ntop(af, (af == AF_INET6) ? (void *)&addr->in6 :
229 				(void *)&addr->in4, buf, sizeof (buf)));
230 }
231