1 /*
2 *
3 * radrealms.c
4 *
5 * A pppd plugin which is stacked on top of radius.so.  This plugin
6 * allows selection of alternate set of servers based on the user's realm.
7 *
8 * Author: Ben McKeegan  ben@netservers.co.uk
9 *
10 * Copyright (C) 2002 Netservers
11 *
12 * This plugin may be distributed according to the terms of the GNU
13 * General Public License, version 2 or (at your option) any later version.
14 *
15 */
16 
17 static char const RCSID[] =
18     "$Id: radrealms.c,v 1.2 2004/11/14 07:26:26 paulus Exp $";
19 
20 #include "pppd.h"
21 #include "radiusclient.h"
22 #include <stdio.h>
23 #include <string.h>
24 #include <stdlib.h>
25 
26 char pppd_version[] = VERSION;
27 
28 char radrealms_config[MAXPATHLEN] = "/etc/radiusclient/realms";
29 
30 static option_t Options[] = {
31     { "realms-config-file", o_string, &radrealms_config,
32       "Configuration file for RADIUS realms", OPT_STATIC, NULL, MAXPATHLEN },
33     { NULL }
34 };
35 
36 extern void (*radius_pre_auth_hook)(char const *user,
37 				    SERVER **authserver,
38 				    SERVER **acctserver);
39 
40 static void
lookup_realm(char const * user,SERVER ** authserver,SERVER ** acctserver)41 lookup_realm(char const *user,
42 	     SERVER **authserver,
43 	     SERVER **acctserver)
44 {
45     char *realm;
46     FILE *fd;
47     SERVER *accts, *auths, *s;
48     char buffer[512], *p;
49     int line = 0;
50 
51     auths = (SERVER *) malloc(sizeof(SERVER));
52     auths->max = 0;
53     accts = (SERVER *) malloc(sizeof(SERVER));
54     accts->max = 0;
55 
56     realm = strrchr(user, '@');
57 
58     if (realm) {
59 	info("Looking up servers for realm '%s'", realm);
60     } else {
61 	info("Looking up servers for DEFAULT realm");
62     }
63     if (realm) {
64 	if (*(++realm) == '\0') {
65 	    realm = NULL;
66 	}
67     }
68 
69     if ((fd = fopen(radrealms_config, "r")) == NULL) {
70 	option_error("cannot open %s", radrealms_config);
71 	return;
72     }
73     info("Reading %s", radrealms_config);
74 
75     while ((fgets(buffer, sizeof(buffer), fd) != NULL)) {
76 	line++;
77 
78 	if ((*buffer == '\n') || (*buffer == '#') || (*buffer == '\0'))
79 	    continue;
80 
81 	buffer[strlen(buffer)-1] = '\0';
82 
83 	p = strtok(buffer, "\t ");
84 
85 	if (p == NULL || (strcmp(p, "authserver") !=0
86 	    && strcmp(p, "acctserver"))) {
87 	    fclose(fd);
88 	    option_error("%s: invalid line %d: %s", radrealms_config,
89 			 line, buffer);
90 	    return;
91 	}
92 	info("Parsing '%s' entry:", p);
93 	s = auths;
94 	if (p[1] == 'c') {
95 	    s = accts;
96 	}
97 	if (s->max >= SERVER_MAX)
98 	    continue;
99 
100 	if ((p = strtok(NULL, "\t ")) == NULL) {
101 	    fclose(fd);
102 	    option_error("%s: realm name missing on line %d: %s",
103 			 radrealms_config, line, buffer);
104 	    return;
105 	}
106 
107 	if ((realm != NULL && strcmp(p, realm) == 0) ||
108 	    (realm == NULL && strcmp(p, "DEFAULT") == 0) ) {
109 	    info(" - Matched realm %s", p);
110 	    if ((p = strtok(NULL, ":")) == NULL) {
111 		fclose(fd);
112 		option_error("%s: server address missing on line %d: %s",
113 			     radrealms_config, line, buffer);
114 		return;
115 	    }
116 	    s->name[s->max] = strdup(p);
117 	    info(" - Address is '%s'",p);
118 	    if ((p = strtok(NULL, "\t ")) == NULL) {
119 		fclose(fd);
120 		option_error("%s: server port missing on line %d:  %s",
121 			     radrealms_config, line, buffer);
122 		return;
123 	    }
124 	    s->port[s->max] = atoi(p);
125 	    info(" - Port is '%d'", s->port[s->max]);
126 	    s->max++;
127 	} else
128 	    info(" - Skipping realm '%s'", p);
129     }
130     fclose(fd);
131 
132     if (accts->max)
133 	*acctserver = accts;
134 
135     if (auths->max)
136 	*authserver = auths;
137 
138     return;
139 }
140 
141 void
plugin_init(void)142 plugin_init(void)
143 {
144     radius_pre_auth_hook = lookup_realm;
145 
146     add_options(Options);
147     info("RADIUS Realms plugin initialized.");
148 }
149