xref: /illumos-gate/usr/src/cmd/smbsrv/smbd/smbd_krb5lookup.c (revision b3700b074e637f8c6991b70754c88a2cfffb246b)
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 
28 #include <smbsrv/libsmbns.h>
29 
30 #include "smbd.h"
31 #include "locate_plugin.h"
32 
33 /* osconf.h - sigh */
34 #define	KRB5_DEFAULT_PORT	88
35 #define	DEFAULT_KADM5_PORT	749
36 #define	DEFAULT_KPASSWD_PORT	464
37 
38 /*
39  * This is an "override plugin" used by libkrb5.  See:
40  * lib/gss_mechs/mech_krb5/krb5/os/locate_kdc.c
41  *
42  * The interface is based on:
43  * http://web.mit.edu/~kerberos/krb5-1.12/doc/plugindev/locate.html
44  */
45 
46 /*
47  * Called by krb5int_locate_server / override_locate_server
48  */
49 
50 krb5_error_code
51 _krb5_override_service_locator(
52     void *arg0,
53     enum locate_service_type svc,
54     const char *realm,
55     int socktype,
56     int family,
57     int (*cbfunc)(void *, int, struct sockaddr *),
58     void *cbdata)
59 {
60 	_NOTE(ARGUNUSED(arg0))
61 	smb_domainex_t dxi;
62 	int rc = KRB5_PLUGIN_NO_HANDLE;
63 	short port;
64 
65 	/*
66 	 * Is this a service we want to override?
67 	 */
68 	switch (svc) {
69 	case locate_service_kdc:
70 	case locate_service_master_kdc:
71 		port = htons(KRB5_DEFAULT_PORT);
72 		break;
73 	case locate_service_kadmin:
74 		port = htons(DEFAULT_KADM5_PORT);
75 		break;
76 	case locate_service_kpasswd:
77 		port = htons(DEFAULT_KPASSWD_PORT);
78 		break;
79 	case locate_service_krb524:
80 	default:
81 		return (rc);
82 	}
83 
84 	/*
85 	 * What's my domain?  Note: have to get this in a way
86 	 * that works while join domain is underway.
87 	 */
88 	if (!smb_domain_getinfo(&dxi)) {
89 		smbd_report("_krb5_override_service_locator "
90 		    "failed getting domain info");
91 		return (KRB5_ERR_HOST_REALM_UNKNOWN);
92 	}
93 
94 	/*
95 	 * Is this a realm we want to override?
96 	 */
97 	if (0 != strcasecmp(realm, dxi.d_primary.di_fqname)) {
98 		syslog(LOG_DEBUG, "_krb5_override_service_locator, "
99 		    "realm=%s, fqdn=%s", realm, dxi.d_primary.di_fqname);
100 		return (rc);
101 	}
102 
103 	/*
104 	 * Yes, this is our domain.  Have a DC?
105 	 */
106 	if (dxi.d_dci.dc_name[0] == '\0' ||
107 	    dxi.d_dci.dc_addr.a_family == 0)
108 		return (KRB5_REALM_CANT_RESOLVE);
109 
110 	switch (family) {
111 	case AF_UNSPEC:
112 		break;	/* OK */
113 	case AF_INET:
114 	case AF_INET6:
115 		if (family == dxi.d_dci.dc_addr.a_family)
116 			break;	/* OK */
117 		/* else fallthrough */
118 	default:
119 		return (KRB5_ERR_NO_SERVICE);
120 	}
121 
122 	/*
123 	 * Provide the service address we have.
124 	 */
125 	switch (dxi.d_dci.dc_addr.a_family) {
126 	case AF_INET: {
127 		struct sockaddr_in sin;
128 		(void) memset(&sin, 0, sizeof (sin));
129 		sin.sin_family = AF_INET;
130 		sin.sin_port = port;
131 		(void) memcpy(&sin.sin_addr, &dxi.d_dci.dc_addr.a_ipv4,
132 		    sizeof (sin.sin_addr));
133 		rc = cbfunc(cbdata, socktype, (struct sockaddr *)&sin);
134 		/* rc from cbfunc is special. */
135 		if (rc)
136 			rc = ENOMEM;
137 		break;
138 	}
139 	case AF_INET6: {
140 		struct sockaddr_in6 sin6;
141 		(void) memset(&sin6, 0, sizeof (sin6));
142 		sin6.sin6_family = AF_INET6;
143 		sin6.sin6_port = port;
144 		(void) memcpy(&sin6.sin6_addr, &dxi.d_dci.dc_addr.a_ipv6,
145 		    sizeof (sin6.sin6_addr));
146 		rc = cbfunc(cbdata, socktype, (struct sockaddr *)&sin6);
147 		/* rc from cbfunc is special. */
148 		if (rc)
149 			rc = ENOMEM;
150 		break;
151 	}
152 	default:
153 		rc = KRB5_ERR_NO_SERVICE;
154 		break;
155 	}
156 
157 	return (rc);
158 }
159