xref: /freebsd/lib/librpcsec_gss/rpcsec_gss_prot.c (revision 2008043f386721d58158e37e0d7e50df8095942d)
1 /*
2   SPDX-License-Identifier: BSD-3-Clause
3 
4   rpcsec_gss_prot.c
5 
6   Copyright (c) 2000 The Regents of the University of Michigan.
7   All rights reserved.
8 
9   Copyright (c) 2000 Dug Song <dugsong@UMICH.EDU>.
10   All rights reserved, all wrongs reversed.
11 
12   Redistribution and use in source and binary forms, with or without
13   modification, are permitted provided that the following conditions
14   are met:
15 
16   1. Redistributions of source code must retain the above copyright
17      notice, this list of conditions and the following disclaimer.
18   2. Redistributions in binary form must reproduce the above copyright
19      notice, this list of conditions and the following disclaimer in the
20      documentation and/or other materials provided with the distribution.
21   3. Neither the name of the University nor the names of its
22      contributors may be used to endorse or promote products derived
23      from this software without specific prior written permission.
24 
25   THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
26   WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
27   MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
28   DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29   FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30   CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31   SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
32   BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
33   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
34   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
35   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 
37   $Id: authgss_prot.c,v 1.18 2000/09/01 04:14:03 dugsong Exp $
38 */
39 
40 #include <stdio.h>
41 #include <stdlib.h>
42 #include <stdarg.h>
43 #include <string.h>
44 #include <rpc/rpc.h>
45 #include <rpc/rpcsec_gss.h>
46 #include "rpcsec_gss_int.h"
47 
48 #define MAX_GSS_SIZE	10240	/* XXX */
49 
50 bool_t
51 xdr_gss_buffer_desc(XDR *xdrs, gss_buffer_desc *p)
52 {
53 	char *val;
54 	u_int len;
55 	bool_t ret;
56 
57 	val = p->value;
58 	len = p->length;
59 	ret = xdr_bytes(xdrs, &val, &len, MAX_GSS_SIZE);
60 	p->value = val;
61 	p->length = len;
62 
63 	return (ret);
64 }
65 
66 bool_t
67 xdr_rpc_gss_cred(XDR *xdrs, struct rpc_gss_cred *p)
68 {
69 	enum_t proc, svc;
70 	bool_t ret;
71 
72 	proc = p->gc_proc;
73 	svc = p->gc_svc;
74 	ret = (xdr_u_int(xdrs, &p->gc_version) &&
75 	    xdr_enum(xdrs, &proc) &&
76 	    xdr_u_int(xdrs, &p->gc_seq) &&
77 	    xdr_enum(xdrs, &svc) &&
78 	    xdr_gss_buffer_desc(xdrs, &p->gc_handle));
79 	p->gc_proc = proc;
80 	p->gc_svc = svc;
81 
82 	return (ret);
83 }
84 
85 bool_t
86 xdr_rpc_gss_init_res(XDR *xdrs, struct rpc_gss_init_res *p)
87 {
88 
89 	return (xdr_gss_buffer_desc(xdrs, &p->gr_handle) &&
90 	    xdr_u_int(xdrs, &p->gr_major) &&
91 	    xdr_u_int(xdrs, &p->gr_minor) &&
92 	    xdr_u_int(xdrs, &p->gr_win) &&
93 	    xdr_gss_buffer_desc(xdrs, &p->gr_token));
94 }
95 
96 bool_t
97 xdr_rpc_gss_wrap_data(XDR *xdrs, xdrproc_t xdr_func, caddr_t xdr_ptr,
98 		      gss_ctx_id_t ctx, gss_qop_t qop,
99 		      rpc_gss_service_t svc, u_int seq)
100 {
101 	gss_buffer_desc	databuf, wrapbuf;
102 	OM_uint32	maj_stat, min_stat;
103 	int		start, end, conf_state;
104 	u_int		len;
105 	bool_t		xdr_stat;
106 
107 	/* Skip databody length. */
108 	start = XDR_GETPOS(xdrs);
109 	XDR_SETPOS(xdrs, start + 4);
110 
111 	/* Marshal rpc_gss_data_t (sequence number + arguments). */
112 	if (!xdr_u_int(xdrs, &seq) || !xdr_func(xdrs, xdr_ptr))
113 		return (FALSE);
114 	end = XDR_GETPOS(xdrs);
115 
116 	/* Set databuf to marshalled rpc_gss_data_t. */
117 	databuf.length = end - start - 4;
118 	XDR_SETPOS(xdrs, start + 4);
119 	databuf.value = XDR_INLINE(xdrs, databuf.length);
120 
121 	xdr_stat = FALSE;
122 
123 	if (svc == rpc_gss_svc_integrity) {
124 		/* Marshal databody_integ length. */
125 		XDR_SETPOS(xdrs, start);
126 		len = databuf.length;
127 		if (!xdr_u_int(xdrs, &len))
128 			return (FALSE);
129 
130 		/* Checksum rpc_gss_data_t. */
131 		maj_stat = gss_get_mic(&min_stat, ctx, qop,
132 				       &databuf, &wrapbuf);
133 		if (maj_stat != GSS_S_COMPLETE) {
134 			log_debug("gss_get_mic failed");
135 			return (FALSE);
136 		}
137 		/* Marshal checksum. */
138 		XDR_SETPOS(xdrs, end);
139 		xdr_stat = xdr_gss_buffer_desc(xdrs, &wrapbuf);
140 		gss_release_buffer(&min_stat, &wrapbuf);
141 	}
142 	else if (svc == rpc_gss_svc_privacy) {
143 		/* Encrypt rpc_gss_data_t. */
144 		maj_stat = gss_wrap(&min_stat, ctx, TRUE, qop, &databuf,
145 				    &conf_state, &wrapbuf);
146 		if (maj_stat != GSS_S_COMPLETE) {
147 			log_status("gss_wrap", NULL, maj_stat, min_stat);
148 			return (FALSE);
149 		}
150 		/* Marshal databody_priv. */
151 		XDR_SETPOS(xdrs, start);
152 		xdr_stat = xdr_gss_buffer_desc(xdrs, &wrapbuf);
153 		gss_release_buffer(&min_stat, &wrapbuf);
154 	}
155 	return (xdr_stat);
156 }
157 
158 bool_t
159 xdr_rpc_gss_unwrap_data(XDR *xdrs, xdrproc_t xdr_func, caddr_t xdr_ptr,
160 			gss_ctx_id_t ctx, gss_qop_t qop,
161 			rpc_gss_service_t svc, u_int seq)
162 {
163 	XDR		tmpxdrs;
164 	gss_buffer_desc	databuf, wrapbuf;
165 	OM_uint32	maj_stat, min_stat;
166 	u_int		seq_num, conf_state, qop_state;
167 	bool_t		xdr_stat;
168 
169 	if (xdr_func == (xdrproc_t) xdr_void || xdr_ptr == NULL)
170 		return (TRUE);
171 
172 	memset(&databuf, 0, sizeof(databuf));
173 	memset(&wrapbuf, 0, sizeof(wrapbuf));
174 
175 	if (svc == rpc_gss_svc_integrity) {
176 		/* Decode databody_integ. */
177 		if (!xdr_gss_buffer_desc(xdrs, &databuf)) {
178 			log_debug("xdr decode databody_integ failed");
179 			return (FALSE);
180 		}
181 		/* Decode checksum. */
182 		if (!xdr_gss_buffer_desc(xdrs, &wrapbuf)) {
183 			mem_free(databuf.value, databuf.length);
184 			log_debug("xdr decode checksum failed");
185 			return (FALSE);
186 		}
187 		/* Verify checksum and QOP. */
188 		maj_stat = gss_verify_mic(&min_stat, ctx, &databuf,
189 					  &wrapbuf, &qop_state);
190 		mem_free(wrapbuf.value, wrapbuf.length);
191 
192 		if (maj_stat != GSS_S_COMPLETE || qop_state != qop) {
193 			mem_free(databuf.value, databuf.length);
194 			log_status("gss_verify_mic", NULL, maj_stat, min_stat);
195 			return (FALSE);
196 		}
197 	} else if (svc == rpc_gss_svc_privacy) {
198 		/* Decode databody_priv. */
199 		if (!xdr_gss_buffer_desc(xdrs, &wrapbuf)) {
200 			log_debug("xdr decode databody_priv failed");
201 			return (FALSE);
202 		}
203 		/* Decrypt databody. */
204 		maj_stat = gss_unwrap(&min_stat, ctx, &wrapbuf, &databuf,
205 				      &conf_state, &qop_state);
206 
207 		mem_free(wrapbuf.value, wrapbuf.length);
208 
209 		/* Verify encryption and QOP. */
210 		if (maj_stat != GSS_S_COMPLETE || qop_state != qop ||
211 			conf_state != TRUE) {
212 			gss_release_buffer(&min_stat, &databuf);
213 			log_status("gss_unwrap", NULL, maj_stat, min_stat);
214 			return (FALSE);
215 		}
216 	}
217 	/* Decode rpc_gss_data_t (sequence number + arguments). */
218 	xdrmem_create(&tmpxdrs, databuf.value, databuf.length, XDR_DECODE);
219 	xdr_stat = (xdr_u_int(&tmpxdrs, &seq_num) &&
220 	    xdr_func(&tmpxdrs, xdr_ptr));
221 	XDR_DESTROY(&tmpxdrs);
222 
223 	/*
224 	 * Integrity service allocates databuf via XDR so free it the
225 	 * same way.
226 	 */
227 	if (svc == rpc_gss_svc_integrity) {
228 		xdr_free((xdrproc_t) xdr_gss_buffer_desc, (char *) &databuf);
229 	} else {
230 		gss_release_buffer(&min_stat, &databuf);
231 	}
232 
233 	/* Verify sequence number. */
234 	if (xdr_stat == TRUE && seq_num != seq) {
235 		log_debug("wrong sequence number in databody");
236 		return (FALSE);
237 	}
238 	return (xdr_stat);
239 }
240 
241 #ifdef DEBUG
242 #include <ctype.h>
243 
244 void
245 log_debug(const char *fmt, ...)
246 {
247 	va_list ap;
248 
249 	va_start(ap, fmt);
250 	fprintf(stderr, "rpcsec_gss: ");
251 	vfprintf(stderr, fmt, ap);
252 	fprintf(stderr, "\n");
253 	va_end(ap);
254 }
255 
256 void
257 log_status(const char *m, gss_OID mech, OM_uint32 maj_stat, OM_uint32 min_stat)
258 {
259 	OM_uint32 min;
260 	gss_buffer_desc msg;
261 	int msg_ctx = 0;
262 
263 	fprintf(stderr, "rpcsec_gss: %s: ", m);
264 
265 	gss_display_status(&min, maj_stat, GSS_C_GSS_CODE, GSS_C_NULL_OID,
266 			   &msg_ctx, &msg);
267 	fprintf(stderr, "%s - ", (char *)msg.value);
268 	gss_release_buffer(&min, &msg);
269 
270 	gss_display_status(&min, min_stat, GSS_C_MECH_CODE, mech,
271 			   &msg_ctx, &msg);
272 	fprintf(stderr, "%s\n", (char *)msg.value);
273 	gss_release_buffer(&min, &msg);
274 }
275 
276 #else
277 
278 void
279 log_debug(__unused const char *fmt, ...)
280 {
281 }
282 
283 void
284 log_status(__unused const char *m, __unused gss_OID mech,
285     __unused OM_uint32 maj_stat, __unused OM_uint32 min_stat)
286 {
287 }
288 
289 #endif
290 
291 
292