xref: /illumos-gate/usr/src/cmd/idmap/idmapd/krb5_lookup.c (revision c5bab7026b8e0ac44b25ee08507ea360f177d844)
1 /*
2  * This file and its contents are supplied under the terms of the
3  * Common Development and Distribution License ("CDDL"), version 1.0.
4  * You may only use this file in accordance with the terms of version
5  * 1.0 of the CDDL.
6  *
7  * A full copy of the text of the CDDL should have accompanied this
8  * source.  A copy of the CDDL is also available via the Internet at
9  * http://www.illumos.org/license/CDDL.
10  */
11 
12 /*
13  * Copyright 2014 Nexenta Systems, Inc.  All rights reserved.
14  */
15 
16 #include <stdio.h>
17 #include <stdlib.h>
18 #include <stdarg.h>
19 #include <string.h>
20 #include <syslog.h>
21 
22 #include <sys/types.h>
23 #include <sys/errno.h>
24 #include <sys/socket.h>
25 #include <netinet/in.h>
26 #include <sys/note.h>
27 #include <synch.h>
28 #include <thread.h>
29 
30 #include "idmapd.h"
31 #include "libadutils.h"
32 #include "locate_plugin.h"
33 
34 /* osconf.h - sigh */
35 #define	KRB5_DEFAULT_PORT	88
36 #define	DEFAULT_KADM5_PORT	749
37 #define	DEFAULT_KPASSWD_PORT	464
38 
39 /*
40  * This is an "override plugin" used by libkrb5.  See:
41  * lib/gss_mechs/mech_krb5/krb5/os/locate_kdc.c
42  *
43  * The interface is based on:
44  * http://web.mit.edu/~kerberos/krb5-1.12/doc/plugindev/locate.html
45  */
46 
47 /*
48  * Called by krb5int_locate_server / override_locate_server
49  */
50 
51 krb5_error_code
52 _krb5_override_service_locator(
53     void *arg0,
54     enum locate_service_type svc,
55     const char *realm,
56     int socktype,
57     int family,
58     int (*cbfunc)(void *, int, struct sockaddr *),
59     void *cbdata)
60 {
61 	_NOTE(ARGUNUSED(arg0))
62 	idmap_pg_config_t *pgcfg;
63 	ad_disc_ds_t *ds;
64 	int rc = KRB5_PLUGIN_NO_HANDLE;
65 	short port;
66 
67 	/*
68 	 * Is this a service we want to override?
69 	 */
70 	switch (svc) {
71 	case locate_service_kdc:
72 	case locate_service_master_kdc:
73 		port = htons(KRB5_DEFAULT_PORT);
74 		break;
75 	case locate_service_kadmin:
76 		port = htons(DEFAULT_KADM5_PORT);
77 		break;
78 	case locate_service_kpasswd:
79 		port = htons(DEFAULT_KPASSWD_PORT);
80 		break;
81 	case locate_service_krb524:
82 	default:
83 		return (rc);
84 	}
85 
86 	RDLOCK_CONFIG();
87 	pgcfg = &_idmapdstate.cfg->pgcfg;
88 
89 	/*
90 	 * Is this a realm we want to override?
91 	 */
92 	if (pgcfg->domain_name == NULL)
93 		goto out;
94 	if (0 != strcasecmp(realm, pgcfg->domain_name))
95 		goto out;
96 
97 	/*
98 	 * Yes, this is our domain.  Have a DC?
99 	 */
100 	if ((ds = pgcfg->domain_controller) == NULL) {
101 		rc = KRB5_REALM_CANT_RESOLVE;
102 		goto out;
103 	}
104 
105 	switch (family) {
106 	case AF_UNSPEC:
107 		break;	/* OK */
108 	case AF_INET:
109 	case AF_INET6:
110 		if (family == ds->addr.ss_family)
111 			break;	/* OK */
112 		/* else fallthrough */
113 	default:
114 		rc = KRB5_ERR_NO_SERVICE;
115 		goto out;
116 	}
117 
118 	/*
119 	 * Provide the service address we have.
120 	 */
121 	switch (ds->addr.ss_family) {
122 	case AF_INET: {
123 		struct sockaddr_in sin;
124 		struct sockaddr_in *dsa = (void *)&ds->addr;
125 		(void) memset(&sin, 0, sizeof (sin));
126 		sin.sin_family = AF_INET;
127 		sin.sin_port = port;
128 		(void) memcpy(&sin.sin_addr, &dsa->sin_addr,
129 		    sizeof (sin.sin_addr));
130 		rc = cbfunc(cbdata, socktype, (struct sockaddr *)&sin);
131 		break;
132 	}
133 	case AF_INET6: {
134 		struct sockaddr_in6 sin6;
135 		struct sockaddr_in6 *dsa6 = (void *)&ds->addr;
136 		(void) memset(&sin6, 0, sizeof (sin6));
137 		sin6.sin6_family = AF_INET6;
138 		sin6.sin6_port = port;
139 		(void) memcpy(&sin6.sin6_addr, &dsa6->sin6_addr,
140 		    sizeof (sin6.sin6_addr));
141 		rc = cbfunc(cbdata, socktype, (struct sockaddr *)&sin6);
142 		break;
143 	}
144 	default:
145 		rc = KRB5_ERR_NO_SERVICE;
146 		goto out;
147 	}
148 	/* rc from cbfunc is special. */
149 	if (rc)
150 		rc = ENOMEM;
151 
152 out:
153 	UNLOCK_CONFIG();
154 
155 	return (rc);
156 }
157