1 /* 2 rpcsec_gss_prot.c 3 4 SPDX-License-Identifier: BSD-3-Clause 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 <sys/cdefs.h> 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/kobj.h> 44 #include <sys/lock.h> 45 #include <sys/malloc.h> 46 #include <sys/mbuf.h> 47 #include <sys/mutex.h> 48 49 #include <rpc/rpc.h> 50 #include <rpc/rpcsec_gss.h> 51 52 #include "rpcsec_gss_int.h" 53 54 #define MAX_GSS_SIZE 10240 /* XXX */ 55 56 #if 0 /* use the one from kgssapi */ 57 bool_t 58 xdr_gss_buffer_desc(XDR *xdrs, gss_buffer_desc *p) 59 { 60 char *val; 61 u_int len; 62 bool_t ret; 63 64 val = p->value; 65 len = p->length; 66 ret = xdr_bytes(xdrs, &val, &len, MAX_GSS_SIZE); 67 p->value = val; 68 p->length = len; 69 70 return (ret); 71 } 72 #endif 73 74 bool_t 75 xdr_rpc_gss_cred(XDR *xdrs, struct rpc_gss_cred *p) 76 { 77 enum_t proc, svc; 78 bool_t ret; 79 80 proc = p->gc_proc; 81 svc = p->gc_svc; 82 ret = (xdr_u_int(xdrs, &p->gc_version) && 83 xdr_enum(xdrs, &proc) && 84 xdr_u_int(xdrs, &p->gc_seq) && 85 xdr_enum(xdrs, &svc) && 86 xdr_gss_buffer_desc(xdrs, &p->gc_handle)); 87 p->gc_proc = proc; 88 p->gc_svc = svc; 89 90 return (ret); 91 } 92 93 bool_t 94 xdr_rpc_gss_init_res(XDR *xdrs, struct rpc_gss_init_res *p) 95 { 96 97 return (xdr_gss_buffer_desc(xdrs, &p->gr_handle) && 98 xdr_u_int(xdrs, &p->gr_major) && 99 xdr_u_int(xdrs, &p->gr_minor) && 100 xdr_u_int(xdrs, &p->gr_win) && 101 xdr_gss_buffer_desc(xdrs, &p->gr_token)); 102 } 103 104 static void 105 put_uint32(struct mbuf **mp, uint32_t v) 106 { 107 struct mbuf *m = *mp; 108 uint32_t n; 109 110 M_PREPEND(m, sizeof(uint32_t), M_WAITOK); 111 n = htonl(v); 112 bcopy(&n, mtod(m, uint32_t *), sizeof(uint32_t)); 113 *mp = m; 114 } 115 116 bool_t 117 xdr_rpc_gss_wrap_data(struct mbuf **argsp, 118 gss_ctx_id_t ctx, gss_qop_t qop, 119 rpc_gss_service_t svc, u_int seq) 120 { 121 struct mbuf *args, *mic; 122 OM_uint32 maj_stat, min_stat; 123 int conf_state; 124 u_int len; 125 static char zpad[4]; 126 127 args = *argsp; 128 129 /* 130 * Prepend the sequence number before calling gss_get_mic or gss_wrap. 131 */ 132 put_uint32(&args, seq); 133 len = m_length(args, NULL); 134 135 if (svc == rpc_gss_svc_integrity) { 136 /* Checksum rpc_gss_data_t. */ 137 maj_stat = gss_get_mic_mbuf(&min_stat, ctx, qop, args, &mic); 138 if (maj_stat != GSS_S_COMPLETE) { 139 rpc_gss_log_debug("gss_get_mic failed"); 140 m_freem(args); 141 return (FALSE); 142 } 143 144 /* 145 * Marshal databody_integ. Note that since args is 146 * already RPC encoded, there will be no padding. 147 */ 148 put_uint32(&args, len); 149 150 /* 151 * Marshal checksum. This is likely to need padding. 152 */ 153 len = m_length(mic, NULL); 154 put_uint32(&mic, len); 155 if (len != RNDUP(len)) { 156 m_append(mic, RNDUP(len) - len, zpad); 157 } 158 159 /* 160 * Concatenate databody_integ with checksum. 161 */ 162 m_cat(args, mic); 163 } else if (svc == rpc_gss_svc_privacy) { 164 /* Encrypt rpc_gss_data_t. */ 165 maj_stat = gss_wrap_mbuf(&min_stat, ctx, TRUE, qop, 166 &args, &conf_state); 167 if (maj_stat != GSS_S_COMPLETE) { 168 rpc_gss_log_status("gss_wrap", NULL, 169 maj_stat, min_stat); 170 return (FALSE); 171 } 172 173 /* 174 * Marshal databody_priv and deal with RPC padding. 175 */ 176 len = m_length(args, NULL); 177 put_uint32(&args, len); 178 if (len != RNDUP(len)) { 179 m_append(args, RNDUP(len) - len, zpad); 180 } 181 } 182 *argsp = args; 183 return (TRUE); 184 } 185 186 static uint32_t 187 get_uint32(struct mbuf **mp) 188 { 189 struct mbuf *m = *mp; 190 uint32_t n; 191 192 if (m->m_len < sizeof(uint32_t)) { 193 m = m_pullup(m, sizeof(uint32_t)); 194 if (!m) { 195 *mp = NULL; 196 return (0); 197 } 198 } 199 bcopy(mtod(m, uint32_t *), &n, sizeof(uint32_t)); 200 m_adj(m, sizeof(uint32_t)); 201 *mp = m; 202 return (ntohl(n)); 203 } 204 205 static void 206 m_trim(struct mbuf *m, int len) 207 { 208 struct mbuf *n; 209 int off; 210 211 if (m == NULL) 212 return; 213 n = m_getptr(m, len, &off); 214 if (n) { 215 n->m_len = off; 216 if (n->m_next) { 217 m_freem(n->m_next); 218 n->m_next = NULL; 219 } 220 } 221 } 222 223 bool_t 224 xdr_rpc_gss_unwrap_data(struct mbuf **resultsp, 225 gss_ctx_id_t ctx, gss_qop_t qop, 226 rpc_gss_service_t svc, u_int seq) 227 { 228 struct mbuf *results, *message, *mic; 229 uint32_t len, cklen; 230 OM_uint32 maj_stat, min_stat; 231 u_int seq_num, conf_state, qop_state; 232 233 results = *resultsp; 234 *resultsp = NULL; 235 236 message = NULL; 237 if (svc == rpc_gss_svc_integrity) { 238 /* 239 * Extract the seq+message part. Remember that there 240 * may be extra RPC padding in the checksum. The 241 * message part is RPC encoded already so no 242 * padding. 243 */ 244 len = get_uint32(&results); 245 message = results; 246 results = m_split(results, len, M_WAITOK); 247 if (!results) { 248 m_freem(message); 249 return (FALSE); 250 } 251 252 /* 253 * Extract the MIC and make it contiguous. 254 */ 255 cklen = get_uint32(&results); 256 if (!results) { 257 m_freem(message); 258 return (FALSE); 259 } 260 KASSERT(cklen <= MHLEN, ("unexpected large GSS-API checksum")); 261 mic = results; 262 if (cklen > mic->m_len) { 263 mic = m_pullup(mic, cklen); 264 if (!mic) { 265 m_freem(message); 266 return (FALSE); 267 } 268 } 269 if (cklen != RNDUP(cklen)) 270 m_trim(mic, cklen); 271 272 /* Verify checksum and QOP. */ 273 maj_stat = gss_verify_mic_mbuf(&min_stat, ctx, 274 message, mic, &qop_state); 275 m_freem(mic); 276 277 if (maj_stat != GSS_S_COMPLETE || qop_state != qop) { 278 m_freem(message); 279 rpc_gss_log_status("gss_verify_mic", NULL, 280 maj_stat, min_stat); 281 return (FALSE); 282 } 283 } else if (svc == rpc_gss_svc_privacy) { 284 /* Decode databody_priv. */ 285 len = get_uint32(&results); 286 if (!results) 287 return (FALSE); 288 289 /* Decrypt databody. */ 290 message = results; 291 if (len != RNDUP(len)) 292 m_trim(message, len); 293 maj_stat = gss_unwrap_mbuf(&min_stat, ctx, &message, 294 &conf_state, &qop_state); 295 296 /* Verify encryption and QOP. */ 297 if (maj_stat != GSS_S_COMPLETE) { 298 rpc_gss_log_status("gss_unwrap", NULL, 299 maj_stat, min_stat); 300 return (FALSE); 301 } 302 if (qop_state != qop || conf_state != TRUE) { 303 m_freem(results); 304 return (FALSE); 305 } 306 } 307 308 /* Decode rpc_gss_data_t (sequence number + arguments). */ 309 seq_num = get_uint32(&message); 310 if (!message) 311 return (FALSE); 312 313 /* Verify sequence number. */ 314 if (seq_num != seq) { 315 rpc_gss_log_debug("wrong sequence number in databody"); 316 m_freem(message); 317 return (FALSE); 318 } 319 320 *resultsp = message; 321 return (TRUE); 322 } 323 324 #ifdef DEBUG 325 #include <machine/stdarg.h> 326 327 void 328 rpc_gss_log_debug(const char *fmt, ...) 329 { 330 va_list ap; 331 332 va_start(ap, fmt); 333 printf("rpcsec_gss: "); 334 vprintf(fmt, ap); 335 printf("\n"); 336 va_end(ap); 337 } 338 339 void 340 rpc_gss_log_status(const char *m, gss_OID mech, OM_uint32 maj_stat, OM_uint32 min_stat) 341 { 342 OM_uint32 min; 343 gss_buffer_desc msg; 344 int msg_ctx = 0; 345 346 printf("rpcsec_gss: %s: ", m); 347 348 gss_display_status(&min, maj_stat, GSS_C_GSS_CODE, GSS_C_NULL_OID, 349 &msg_ctx, &msg); 350 printf("%s - ", (char *)msg.value); 351 gss_release_buffer(&min, &msg); 352 353 gss_display_status(&min, min_stat, GSS_C_MECH_CODE, mech, 354 &msg_ctx, &msg); 355 printf("%s\n", (char *)msg.value); 356 gss_release_buffer(&min, &msg); 357 } 358 359 #else 360 361 void 362 rpc_gss_log_debug(__unused const char *fmt, ...) 363 { 364 } 365 366 void 367 rpc_gss_log_status(__unused const char *m, __unused gss_OID mech, 368 __unused OM_uint32 maj_stat, __unused OM_uint32 min_stat) 369 { 370 } 371 372 #endif 373 374 375