lib/libipsec/policy_parse.y

   1 /*      $FreeBSD: src/lib/libipsec/policy_parse.y,v 1.1.2.1 2000/07/15 07:24:04 kris Exp $      */
   2 /*      $DragonFly: src/lib/libipsec/policy_parse.y,v 1.3 2003/11/12 21:21:30 eirikn Exp $      */
   3 /*      $KAME: policy_parse.y,v 1.10 2000/05/07 05:25:03 itojun Exp $   */
   4
   5 /*
   6  * Copyright (C) 1995, 1996, 1997, 1998, and 1999 WIDE Project.
   7  * All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. Neither the name of the project nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 /*
  35  * IN/OUT bound policy configuration take place such below:
  36  *      in <policy>
  37  *      out <policy>
  38  *
  39  * <policy> is one of following:
  40  *      "discard", "none", "ipsec <requests>", "entrust", "bypass",
  41  *
  42  * The following requests are accepted as <requests>:
  43  *
  44  *      protocol/mode/src-dst/level
  45  *      protocol/mode/src-dst           parsed as protocol/mode/src-dst/default
  46  *      protocol/mode/src-dst/          parsed as protocol/mode/src-dst/default
  47  *      protocol/transport              parsed as protocol/mode/any-any/default
  48  *      protocol/transport//level       parsed as protocol/mode/any-any/level
  49  *
  50  * You can concatenate these requests with either ' '(single space) or '\n'.
  51  */
  52
  53 %{
  54 #include <sys/types.h>
  55 #include <sys/param.h>
  56 #include <sys/socket.h>
  57
  58 #include <netinet/in.h>
  59 #include <netinet6/ipsec.h>
  60
  61 #include <stdlib.h>
  62 #include <stdio.h>
  63 #include <string.h>
  64 #include <netdb.h>
  65
  66 #include "ipsec_strerror.h"
  67
  68 #define ATOX(c) \
  69   (isdigit(c) ? (c - '0') : (isupper(c) ? (c - 'A' + 10) : (c - 'a' + 10) ))
  70
  71 static caddr_t pbuf = NULL;             /* sadb_x_policy buffer */
  72 static int tlen = 0;                    /* total length of pbuf */
  73 static int offset = 0;                  /* offset of pbuf */
  74 static int p_dir, p_type, p_protocol, p_mode, p_level, p_reqid;
  75 static struct sockaddr *p_src = NULL;
  76 static struct sockaddr *p_dst = NULL;
  77
  78 struct _val;
  79 extern void yyerror (char *msg);
  80 static struct sockaddr *parse_sockaddr (struct _val *buf);
  81 static int rule_check (void);
  82 static int init_x_policy (void);
  83 static int set_x_request (struct sockaddr *src, struct sockaddr *dst);
  84 static int set_sockaddr (struct sockaddr *addr);
  85 static void policy_parse_request_init (void);
  86 static caddr_t policy_parse (char *msg, int msglen);
  87
  88 extern void __policy__strbuffer__init__ (char *msg);
  89 extern int yyparse (void);
  90 extern int yylex (void);
  91
  92 %}
  93
  94 %union {
  95         u_int num;
  96         struct _val {
  97                 int len;
  98                 char *buf;
  99         } val;
 100 }
 101
 102 %token DIR ACTION PROTOCOL MODE LEVEL LEVEL_SPECIFY
 103 %token IPADDRESS
 104 %token ME ANY
 105 %token SLASH HYPHEN
 106 %type <num> DIR ACTION PROTOCOL MODE LEVEL
 107 %type <val> IPADDRESS LEVEL_SPECIFY
 108
 109 %%
 110 policy_spec
 111         :       DIR ACTION
 112                 {
 113                         p_dir = $1;
 114                         p_type = $2;
 115
 116                         if (init_x_policy())
 117                                 return -1;
 118                 }
 119                 rules
 120         |       DIR
 121                 {
 122                         p_dir = $1;
 123                         p_type = 0;     /* ignored it by kernel */
 124
 125                         if (init_x_policy())
 126                                 return -1;
 127                 }
 128         ;
 129
 130 rules
 131         :       /*NOTHING*/
 132         |       rules rule {
 133                         if (rule_check() < 0)
 134                                 return -1;
 135
 136                         if (set_x_request(p_src, p_dst) < 0)
 137                                 return -1;
 138
 139                         policy_parse_request_init();
 140                 }
 141         ;
 142
 143 rule
 144         :       protocol SLASH mode SLASH addresses SLASH level
 145         |       protocol SLASH mode SLASH addresses SLASH
 146         |       protocol SLASH mode SLASH addresses
 147         |       protocol SLASH mode SLASH
 148         |       protocol SLASH mode SLASH SLASH level
 149         |       protocol SLASH mode
 150         |       protocol SLASH {
 151                         __ipsec_errcode = EIPSEC_FEW_ARGUMENTS;
 152                         return -1;
 153                 }
 154         |       protocol {
 155                         __ipsec_errcode = EIPSEC_FEW_ARGUMENTS;
 156                         return -1;
 157                 }
 158         ;
 159
 160 protocol
 161         :       PROTOCOL { p_protocol = $1; }
 162         ;
 163
 164 mode
 165         :       MODE { p_mode = $1; }
 166         ;
 167
 168 level
 169         :       LEVEL {
 170                         p_level = $1;
 171                         p_reqid = 0;
 172                 }
 173         |       LEVEL_SPECIFY {
 174                         p_level = IPSEC_LEVEL_UNIQUE;
 175                         p_reqid = atol($1.buf); /* atol() is good. */
 176                 }
 177         ;
 178
 179 addresses
 180         :       IPADDRESS {
 181                         p_src = parse_sockaddr(&$1);
 182                         if (p_src == NULL)
 183                                 return -1;
 184                 }
 185                 HYPHEN
 186                 IPADDRESS {
 187                         p_dst = parse_sockaddr(&$4);
 188                         if (p_dst == NULL)
 189                                 return -1;
 190                 }
 191         |       ME HYPHEN ANY {
 192                         if (p_dir != IPSEC_DIR_OUTBOUND) {
 193                                 __ipsec_errcode = EIPSEC_INVAL_DIR;
 194                                 return -1;
 195                         }
 196                 }
 197         |       ANY HYPHEN ME {
 198                         if (p_dir != IPSEC_DIR_INBOUND) {
 199                                 __ipsec_errcode = EIPSEC_INVAL_DIR;
 200                                 return -1;
 201                         }
 202                 }
 203                 /*
 204         |       ME HYPHEN ME
 205                 */
 206         ;
 207
 208 %%
 209
 210 void
 211 yyerror(msg)
 212         char *msg;
 213 {
 214         extern char *__libipsecyytext;  /*XXX*/
 215
 216         fprintf(stderr, "libipsec: %s while parsing \"%s\"\n",
 217                 msg, __libipsecyytext);
 218
 219         return;
 220 }
 221
 222 static struct sockaddr *
 223 parse_sockaddr(buf)
 224         struct _val *buf;
 225 {
 226         struct addrinfo hints, *res;
 227         char *serv = NULL;
 228         int error;
 229         struct sockaddr *newaddr = NULL;
 230
 231         memset(&hints, 0, sizeof(hints));
 232         hints.ai_family = PF_UNSPEC;
 233         hints.ai_flags = AI_NUMERICHOST;
 234         error = getaddrinfo(buf->buf, serv, &hints, &res);
 235         if (error != 0) {
 236                 yyerror("invalid IP address");
 237                 __ipsec_set_strerror(gai_strerror(error));
 238                 return NULL;
 239         }
 240
 241         if (res->ai_addr == NULL) {
 242                 yyerror("invalid IP address");
 243                 __ipsec_set_strerror(gai_strerror(error));
 244                 return NULL;
 245         }
 246
 247         newaddr = malloc(res->ai_addr->sa_len);
 248         if (newaddr == NULL) {
 249                 __ipsec_errcode = EIPSEC_NO_BUFS;
 250                 freeaddrinfo(res);
 251                 return NULL;
 252         }
 253         memcpy(newaddr, res->ai_addr, res->ai_addr->sa_len);
 254
 255         freeaddrinfo(res);
 256
 257         __ipsec_errcode = EIPSEC_NO_ERROR;
 258         return newaddr;
 259 }
 260
 261 static int
 262 rule_check()
 263 {
 264         if (p_type == IPSEC_POLICY_IPSEC) {
 265                 if (p_protocol == IPPROTO_IP) {
 266                         __ipsec_errcode = EIPSEC_NO_PROTO;
 267                         return -1;
 268                 }
 269
 270                 if (p_mode != IPSEC_MODE_TRANSPORT
 271                  && p_mode != IPSEC_MODE_TUNNEL) {
 272                         __ipsec_errcode = EIPSEC_INVAL_MODE;
 273                         return -1;
 274                 }
 275
 276                 if (p_src == NULL && p_dst == NULL) {
 277                          if (p_mode != IPSEC_MODE_TRANSPORT) {
 278                                 __ipsec_errcode = EIPSEC_INVAL_ADDRESS;
 279                                 return -1;
 280                         }
 281                 }
 282                 else if (p_src->sa_family != p_dst->sa_family) {
 283                         __ipsec_errcode = EIPSEC_FAMILY_MISMATCH;
 284                         return -1;
 285                 }
 286         }
 287
 288         __ipsec_errcode = EIPSEC_NO_ERROR;
 289         return 0;
 290 }
 291
 292 static int
 293 init_x_policy()
 294 {
 295         struct sadb_x_policy *p;
 296
 297         tlen = sizeof(struct sadb_x_policy);
 298
 299         pbuf = malloc(tlen);
 300         if (pbuf == NULL) {
 301                 __ipsec_errcode = EIPSEC_NO_BUFS;
 302                 return -1;
 303         }
 304         p = (struct sadb_x_policy *)pbuf;
 305         p->sadb_x_policy_len = 0;       /* must update later */
 306         p->sadb_x_policy_exttype = SADB_X_EXT_POLICY;
 307         p->sadb_x_policy_type = p_type;
 308         p->sadb_x_policy_dir = p_dir;
 309         p->sadb_x_policy_reserved = 0;
 310         offset = tlen;
 311
 312         __ipsec_errcode = EIPSEC_NO_ERROR;
 313         return 0;
 314 }
 315
 316 static int
 317 set_x_request(src, dst)
 318         struct sockaddr *src, *dst;
 319 {
 320         struct sadb_x_ipsecrequest *p;
 321         int reqlen;
 322
 323         reqlen = sizeof(*p)
 324                 + (src ? src->sa_len : 0)
 325                 + (dst ? dst->sa_len : 0);
 326         tlen += reqlen;         /* increment to total length */
 327
 328         pbuf = realloc(pbuf, tlen);
 329         if (pbuf == NULL) {
 330                 __ipsec_errcode = EIPSEC_NO_BUFS;
 331                 return -1;
 332         }
 333         p = (struct sadb_x_ipsecrequest *)&pbuf[offset];
 334         p->sadb_x_ipsecrequest_len = reqlen;
 335         p->sadb_x_ipsecrequest_proto = p_protocol;
 336         p->sadb_x_ipsecrequest_mode = p_mode;
 337         p->sadb_x_ipsecrequest_level = p_level;
 338         p->sadb_x_ipsecrequest_reqid = p_reqid;
 339         offset += sizeof(*p);
 340
 341         if (set_sockaddr(src) || set_sockaddr(dst))
 342                 return -1;
 343
 344         __ipsec_errcode = EIPSEC_NO_ERROR;
 345         return 0;
 346 }
 347
 348 static int
 349 set_sockaddr(addr)
 350         struct sockaddr *addr;
 351 {
 352         if (addr == NULL) {
 353                 __ipsec_errcode = EIPSEC_NO_ERROR;
 354                 return 0;
 355         }
 356
 357         /* tlen has already incremented */
 358
 359         memcpy(&pbuf[offset], addr, addr->sa_len);
 360
 361         offset += addr->sa_len;
 362
 363         __ipsec_errcode = EIPSEC_NO_ERROR;
 364         return 0;
 365 }
 366
 367 static void
 368 policy_parse_request_init()
 369 {
 370         p_protocol = IPPROTO_IP;
 371         p_mode = IPSEC_MODE_ANY;
 372         p_level = IPSEC_LEVEL_DEFAULT;
 373         p_reqid = 0;
 374         if (p_src != NULL) {
 375                 free(p_src);
 376                 p_src = NULL;
 377         }
 378         if (p_dst != NULL) {
 379                 free(p_dst);
 380                 p_dst = NULL;
 381         }
 382
 383         return;
 384 }
 385
 386 static caddr_t
 387 policy_parse(msg, msglen)
 388         char *msg;
 389         int msglen;
 390 {
 391         int error;
 392         pbuf = NULL;
 393         tlen = 0;
 394
 395         /* initialize */
 396         p_dir = IPSEC_DIR_INVALID;
 397         p_type = IPSEC_POLICY_DISCARD;
 398         policy_parse_request_init();
 399         __policy__strbuffer__init__(msg);
 400
 401         error = yyparse();      /* it must be set errcode. */
 402         if (error) {
 403                 if (pbuf != NULL)
 404                         free(pbuf);
 405                 return NULL;
 406         }
 407
 408         /* update total length */
 409         ((struct sadb_x_policy *)pbuf)->sadb_x_policy_len = PFKEY_UNIT64(tlen);
 410
 411         __ipsec_errcode = EIPSEC_NO_ERROR;
 412
 413         return pbuf;
 414 }
 415
 416 caddr_t
 417 ipsec_set_policy(msg, msglen)
 418         char *msg;
 419         int msglen;
 420 {
 421         caddr_t policy;
 422
 423         policy = policy_parse(msg, msglen);
 424         if (policy == NULL) {
 425                 if (__ipsec_errcode == EIPSEC_NO_ERROR)
 426                         __ipsec_errcode = EIPSEC_INVAL_ARGUMENT;
 427                 return NULL;
 428         }
 429
 430         __ipsec_errcode = EIPSEC_NO_ERROR;
 431         return policy;
 432 }
 433