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 (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*
28  * This contains miscellaneous functions moved from commands to the library.
29  */
30 
31 #include "mt.h"
32 #include <stdlib.h>
33 #include <stdio.h>
34 #include <syslog.h>
35 #include <string.h>
36 #include <unistd.h>
37 #include <gssapi/gssapi.h>
38 #include <rpc/rpc.h>
39 #include <rpcsvc/nis.h>
40 #include <rpcsvc/nis_dhext.h>
41 #include <rpc/auth.h>
42 #include <rpc/auth_sys.h>
43 #include <rpc/auth_des.h>
44 #include <rpc/key_prot.h>
45 #include <netdir.h>
46 #include <netconfig.h>
47 #include <sys/socket.h>
48 #include <netinet/in.h>
49 #include <netdb.h>
50 #include <dlfcn.h>
51 #include <gssapi/gssapi.h>
52 
53 extern int bin2hex(int len, unsigned char *binnum, char *hexnum);
54 extern int hex2bin(int len, char *hexnum, char *binnum);
55 
56 #define	MECH_LIB_PREFIX1	"/usr/lib/"
57 
58 #ifdef  _LP64
59 
60 #define	MECH_LIB_PREFIX2	"64/"
61 
62 #else   /* _LP64 */
63 
64 #define	MECH_LIB_PREFIX2	""
65 
66 #endif  /* _LP64 */
67 
68 #define	MECH_LIB_DIR		"gss/"
69 
70 #define	MECH_LIB_PREFIX MECH_LIB_PREFIX1 MECH_LIB_PREFIX2
71 
72 #define	MECHDH		MECH_LIB_PREFIX MECH_LIB_DIR "mech_dh.so.1"
73 #define	LIBGSS		MECH_LIB_PREFIX "libgss.so.1"
74 
75 static gss_OID_desc __dh_gss_c_nt_netname = {
76 	9,  "\053\006\004\001\052\002\032\001\001"
77 };
78 
79 mutex_t gss_load_lock = DEFAULTMUTEX;
80 static gss_OID GSS_EXPORT_NAME = 0;
81 static gss_OID DH_NETNAME = &__dh_gss_c_nt_netname;
82 
83 typedef OM_uint32 (*gss_fptr)();
84 OM_uint32 (*g_import_name)();
85 OM_uint32 (*g_display_name)();
86 OM_uint32 (*g_release_name)();
87 OM_uint32 (*g_release_buffer)();
88 OM_uint32 (*g_release_oid)();
89 
90 /*
91  * gss_OID_load()
92  *
93  * This routine is called by __nis_gssprin2netname to define values for
94  * the gss-api-export-name OID, the Diffie-Hellman netname OID, and
95  * the gss support routines that it needs.
96  * The reason for this support routine is that libnsl cannot have an
97  * explicit dependency on libgss. Callers of __nisgssprin2netname are
98  * expected to have loaded libgss through the rpcsec layer. The work around
99  * is to dlopen the needed shared objects and grab the symbols with dlsym.
100  * This routine opens libgss RTLD_NOLOAD. If this fails then libgss.so.1
101  * is not loaded and we return error. Otherwise it uses dlsym to
102  * defines GSS_EXPORT_NAME to have the value of GSS_C_NT_EXPORT_NAME and
103  * to assign the above fuction pointers.
104  * If this succeeds then the routine will attempt to load mech_dh.so.1
105  * and over ride DH_NETNAME with the value of __DH_GSS_C_NT_NETNAME from
106  * that shared object. We don't consider it an error if this fails because
107  * its conceivable that another mechanism backend will support the netname
108  * name type and mech_dh.so.1 not be available.
109  *
110  * Return 0 on failer, 1 on success.
111  */
112 
113 static int
gss_OID_load()114 gss_OID_load()
115 {
116 	void *dh;
117 	gss_OID *OIDptr;
118 	int stat = 0;
119 
120 	(void) mutex_lock(&gss_load_lock);
121 	if (GSS_EXPORT_NAME) {
122 		(void) mutex_unlock(&gss_load_lock);
123 		return (0);
124 	}
125 
126 	/* if LIBGSS is not loaded return an error */
127 	if ((dh = dlopen(LIBGSS, RTLD_NOLOAD)) == NULL) {
128 		(void) mutex_unlock(&gss_load_lock);
129 		return (0);
130 	}
131 
132 	OIDptr = (gss_OID *)dlsym(dh, "GSS_C_NT_EXPORT_NAME");
133 	if (OIDptr)
134 		GSS_EXPORT_NAME = *OIDptr;
135 	else
136 		goto Done;
137 
138 	g_import_name = (gss_fptr)dlsym(dh, "gss_import_name");
139 	if (g_import_name == 0)
140 		goto Done;
141 
142 	g_display_name = (gss_fptr)dlsym(dh, "gss_display_name");
143 	if (g_display_name == 0)
144 		goto Done;
145 
146 	g_release_name = (gss_fptr)dlsym(dh, "gss_release_name");
147 	if (g_release_name == 0)
148 		goto Done;
149 
150 	g_release_buffer = (gss_fptr)dlsym(dh, "gss_release_buffer");
151 	if (g_release_buffer == 0)
152 		goto Done;
153 
154 	g_release_oid = (gss_fptr)dlsym(dh, "gss_release_oid");
155 	if (g_release_oid == 0)
156 		goto Done;
157 
158 	stat = 1;
159 	/*
160 	 * Try and get the official netname oid from mech_dh.so.
161 	 * If this fails will just keep our default from above.
162 	 */
163 
164 	if ((dh = dlopen(MECHDH, RTLD_LAZY)) != NULL) {
165 
166 		OIDptr = (gss_OID *)dlsym(dh, "__DH_GSS_C_NT_NETNAME");
167 		if (OIDptr)
168 			DH_NETNAME = *OIDptr;
169 	}
170 
171 Done:
172 	(void) mutex_unlock(&gss_load_lock);
173 
174 	if (stat == 0)
175 		GSS_EXPORT_NAME = 0;
176 
177 	return (stat);
178 }
179 
180 
181 /*
182  * int
183  * __nis_gssprin2netname(rpc_gss_principal_t prin,
184  *			 char netname[MAXNETNAMELEN+1])
185  *
186  * This routine attempts to extract the netname from an rpc_gss_principal_t
187  * which is in { gss-api-exorted-name } format. Return 0 if a netname was
188  * found, else return -1.
189  */
190 
191 /*
192  * This routine has a dependency on libgss.so. So we will pragma weak
193  * the interfaces that we need. When this routine is called libgss
194  * should have been loaded by the rpcsec layer. We will call gss_OID_load
195  * to get the value for GSS_EXPORT_NAME. If gss_OID_load failes return -1.
196  */
197 
198 #define	OID_IS_EQUAL(o1, o2) ((o1) && (o2) && \
199 	((o1)->length == (o2)->length) && \
200 	(memcmp((o1)->elements, (o2)->elements, (o1)->length) == 0))
201 
202 int
__nis_gssprin2netname(rpc_gss_principal_t prin,char netname[MAXNETNAMELEN+1])203 __nis_gssprin2netname(rpc_gss_principal_t prin, char netname[MAXNETNAMELEN+1])
204 {
205 	gss_buffer_desc display_name;
206 	gss_name_t name;
207 	gss_OID name_type;
208 	gss_buffer_desc expName;
209 	int stat = -1;
210 	OM_uint32 major, minor;
211 
212 	/* See if we already got the OID */
213 	if (GSS_EXPORT_NAME == 0) {
214 		/* Nope. See if GSS is loaded and get the OIDs */
215 		if (!gss_OID_load())
216 			return (-1);	/* if libgss.so.1 isn't loaded */
217 	}
218 
219 	expName.length = prin->len;
220 	expName.value = prin->name;
221 
222 	major = (*g_import_name)(&minor, &expName,
223 	    (gss_OID) GSS_EXPORT_NAME, &name);
224 
225 	if (major == GSS_S_COMPLETE) {
226 		major = (*g_display_name)(&minor, name,
227 		    &display_name, &name_type);
228 
229 		/* We're done with the gss_internal name */
230 		(void) (*g_release_name)(&minor, &name);
231 
232 		if (major == GSS_S_COMPLETE) {
233 			/*
234 			 * Check if we've got a netname. If we do we copy it
235 			 * and make sure that its null terminated.
236 			 */
237 			if (OID_IS_EQUAL(DH_NETNAME, name_type)) {
238 				(void) strncpy(netname,
239 				    (char *)display_name.value,
240 				    MAXNETNAMELEN);
241 				netname[MAXNETNAMELEN] = '\0';
242 				stat = 0;
243 			}
244 			/*
245 			 * If there are other display formats that can
246 			 * be converted to netnames easily, insert here.
247 			 *
248 			 * else if (OID_IS_EQUAL(OTHER_NT_OID, name_type)) {
249 			 *	convert2netname(display_name.value, netname);
250 			 * } ...
251 			 */
252 
253 			/* Release temporty storage */
254 			(void) (*g_release_buffer)(&minor, &display_name);
255 			(void) (*g_release_oid)(&minor, &name_type);
256 		}
257 	}
258 
259 	if (stat == 0)
260 		return (stat);
261 
262 	return (stat);
263 }
264 
265 /*
266  * Extract a public key given a key length and alg. type from a packed
267  * netobj containing extended Diffie-Hellman keys.
268  */
269 char *
__nis_dhext_extract_pkey(netobj * no,keylen_t keylen,algtype_t algtype)270 __nis_dhext_extract_pkey(netobj *no, keylen_t keylen, algtype_t algtype)
271 {
272 	char		*hexkey;
273 	/* LINTED pointer cast */
274 	extdhkey_t	*keyent = (extdhkey_t *)no->n_bytes;
275 
276 	/* LINTED pointer cast */
277 	while (keyent < (extdhkey_t *)(no->n_bytes + no->n_len)) {
278 		char	*keyoffset;
279 		size_t	binlen = (ntohs(keyent->keylen) + 7) / 8;
280 		size_t	binpadlen = ((binlen + 3) / 4) * 4;
281 		size_t	hexkeylen = binlen * 2 + 1;
282 
283 		if (keylen == ntohs(keyent->keylen) &&
284 		    algtype == ntohs(keyent->algtype)) {
285 
286 			if (!(hexkey = malloc(hexkeylen)))
287 				return (NULL);
288 
289 			(void) bin2hex(binlen, keyent->key, hexkey);
290 			return (hexkey);
291 		}
292 		keyoffset = (char *)keyent + (sizeof (ushort_t) * 2) +
293 		    binpadlen;
294 		/* LINTED pointer cast */
295 		keyent = (extdhkey_t *)keyoffset;
296 	}
297 	return (NULL);
298 }
299