crypto/asn1/tasn_utl.c

   1 /* tasn_utl.c */
   2 /*
   3  * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project
   4  * 2000.
   5  */
   6 /* ====================================================================
   7  * Copyright (c) 2000-2004 The OpenSSL Project.  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  *
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  *
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in
  18  *    the documentation and/or other materials provided with the
  19  *    distribution.
  20  *
  21  * 3. All advertising materials mentioning features or use of this
  22  *    software must display the following acknowledgment:
  23  *    "This product includes software developed by the OpenSSL Project
  24  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
  25  *
  26  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  27  *    endorse or promote products derived from this software without
  28  *    prior written permission. For written permission, please contact
  29  *    licensing@OpenSSL.org.
  30  *
  31  * 5. Products derived from this software may not be called "OpenSSL"
  32  *    nor may "OpenSSL" appear in their names without prior written
  33  *    permission of the OpenSSL Project.
  34  *
  35  * 6. Redistributions of any form whatsoever must retain the following
  36  *    acknowledgment:
  37  *    "This product includes software developed by the OpenSSL Project
  38  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
  39  *
  40  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  41  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  43  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  44  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  45  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  46  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  47  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  49  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  50  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  51  * OF THE POSSIBILITY OF SUCH DAMAGE.
  52  * ====================================================================
  53  *
  54  * This product includes cryptographic software written by Eric Young
  55  * (eay@cryptsoft.com).  This product includes software written by Tim
  56  * Hudson (tjh@cryptsoft.com).
  57  *
  58  */
  59
  60 #include <stddef.h>
  61 #include <string.h>
  62 #include <openssl/asn1.h>
  63 #include <openssl/asn1t.h>
  64 #include <openssl/objects.h>
  65 #include <openssl/err.h>
  66
  67 /* Utility functions for manipulating fields and offsets */
  68
  69 /* Add 'offset' to 'addr' */
  70 #define offset2ptr(addr, offset) (void *)(((char *) addr) + offset)
  71
  72 /*
  73  * Given an ASN1_ITEM CHOICE type return the selector value
  74  */
  75
  76 int asn1_get_choice_selector(ASN1_VALUE **pval, const ASN1_ITEM *it)
  77 {
  78     int *sel = offset2ptr(*pval, it->utype);
  79     return *sel;
  80 }
  81
  82 /*
  83  * Given an ASN1_ITEM CHOICE type set the selector value, return old value.
  84  */
  85
  86 int asn1_set_choice_selector(ASN1_VALUE **pval, int value,
  87                              const ASN1_ITEM *it)
  88 {
  89     int *sel, ret;
  90     sel = offset2ptr(*pval, it->utype);
  91     ret = *sel;
  92     *sel = value;
  93     return ret;
  94 }
  95
  96 /*
  97  * Do reference counting. The value 'op' decides what to do. if it is +1
  98  * then the count is incremented. If op is 0 count is set to 1. If op is -1
  99  * count is decremented and the return value is the current refrence count or
 100  * 0 if no reference count exists.
 101  */
 102
 103 int asn1_do_lock(ASN1_VALUE **pval, int op, const ASN1_ITEM *it)
 104 {
 105     const ASN1_AUX *aux;
 106     int *lck, ret;
 107     if ((it->itype != ASN1_ITYPE_SEQUENCE)
 108         && (it->itype != ASN1_ITYPE_NDEF_SEQUENCE))
 109         return 0;
 110     aux = it->funcs;
 111     if (!aux || !(aux->flags & ASN1_AFLG_REFCOUNT))
 112         return 0;
 113     lck = offset2ptr(*pval, aux->ref_offset);
 114     if (op == 0) {
 115         *lck = 1;
 116         return 1;
 117     }
 118     ret = CRYPTO_add(lck, op, aux->ref_lock);
 119 #ifdef REF_PRINT
 120     fprintf(stderr, "%s: Reference Count: %d\n", it->sname, *lck);
 121 #endif
 122 #ifdef REF_CHECK
 123     if (ret < 0)
 124         fprintf(stderr, "%s, bad reference count\n", it->sname);
 125 #endif
 126     return ret;
 127 }
 128
 129 static ASN1_ENCODING *asn1_get_enc_ptr(ASN1_VALUE **pval, const ASN1_ITEM *it)
 130 {
 131     const ASN1_AUX *aux;
 132     if (!pval || !*pval)
 133         return NULL;
 134     aux = it->funcs;
 135     if (!aux || !(aux->flags & ASN1_AFLG_ENCODING))
 136         return NULL;
 137     return offset2ptr(*pval, aux->enc_offset);
 138 }
 139
 140 void asn1_enc_init(ASN1_VALUE **pval, const ASN1_ITEM *it)
 141 {
 142     ASN1_ENCODING *enc;
 143     enc = asn1_get_enc_ptr(pval, it);
 144     if (enc) {
 145         enc->enc = NULL;
 146         enc->len = 0;
 147         enc->modified = 1;
 148     }
 149 }
 150
 151 void asn1_enc_free(ASN1_VALUE **pval, const ASN1_ITEM *it)
 152 {
 153     ASN1_ENCODING *enc;
 154     enc = asn1_get_enc_ptr(pval, it);
 155     if (enc) {
 156         if (enc->enc)
 157             OPENSSL_free(enc->enc);
 158         enc->enc = NULL;
 159         enc->len = 0;
 160         enc->modified = 1;
 161     }
 162 }
 163
 164 int asn1_enc_save(ASN1_VALUE **pval, const unsigned char *in, int inlen,
 165                   const ASN1_ITEM *it)
 166 {
 167     ASN1_ENCODING *enc;
 168     enc = asn1_get_enc_ptr(pval, it);
 169     if (!enc)
 170         return 1;
 171
 172     if (enc->enc)
 173         OPENSSL_free(enc->enc);
 174     enc->enc = OPENSSL_malloc(inlen);
 175     if (!enc->enc)
 176         return 0;
 177     memcpy(enc->enc, in, inlen);
 178     enc->len = inlen;
 179     enc->modified = 0;
 180
 181     return 1;
 182 }
 183
 184 int asn1_enc_restore(int *len, unsigned char **out, ASN1_VALUE **pval,
 185                      const ASN1_ITEM *it)
 186 {
 187     ASN1_ENCODING *enc;
 188     enc = asn1_get_enc_ptr(pval, it);
 189     if (!enc || enc->modified)
 190         return 0;
 191     if (out) {
 192         memcpy(*out, enc->enc, enc->len);
 193         *out += enc->len;
 194     }
 195     if (len)
 196         *len = enc->len;
 197     return 1;
 198 }
 199
 200 /* Given an ASN1_TEMPLATE get a pointer to a field */
 201 ASN1_VALUE **asn1_get_field_ptr(ASN1_VALUE **pval, const ASN1_TEMPLATE *tt)
 202 {
 203     ASN1_VALUE **pvaltmp;
 204     if (tt->flags & ASN1_TFLG_COMBINE)
 205         return pval;
 206     pvaltmp = offset2ptr(*pval, tt->offset);
 207     /*
 208      * NOTE for BOOLEAN types the field is just a plain int so we can't
 209      * return int **, so settle for (int *).
 210      */
 211     return pvaltmp;
 212 }
 213
 214 /*
 215  * Handle ANY DEFINED BY template, find the selector, look up the relevant
 216  * ASN1_TEMPLATE in the table and return it.
 217  */
 218
 219 const ASN1_TEMPLATE *asn1_do_adb(ASN1_VALUE **pval, const ASN1_TEMPLATE *tt,
 220                                  int nullerr)
 221 {
 222     const ASN1_ADB *adb;
 223     const ASN1_ADB_TABLE *atbl;
 224     long selector;
 225     ASN1_VALUE **sfld;
 226     int i;
 227     if (!(tt->flags & ASN1_TFLG_ADB_MASK))
 228         return tt;
 229
 230     /* Else ANY DEFINED BY ... get the table */
 231     adb = ASN1_ADB_ptr(tt->item);
 232
 233     /* Get the selector field */
 234     sfld = offset2ptr(*pval, adb->offset);
 235
 236     /* Check if NULL */
 237     if (!sfld) {
 238         if (!adb->null_tt)
 239             goto err;
 240         return adb->null_tt;
 241     }
 242
 243     /*
 244      * Convert type to a long: NB: don't check for NID_undef here because it
 245      * might be a legitimate value in the table
 246      */
 247     if (tt->flags & ASN1_TFLG_ADB_OID)
 248         selector = OBJ_obj2nid((ASN1_OBJECT *)*sfld);
 249     else
 250         selector = ASN1_INTEGER_get((ASN1_INTEGER *)*sfld);
 251
 252     /*
 253      * Try to find matching entry in table Maybe should check application
 254      * types first to allow application override? Might also be useful to
 255      * have a flag which indicates table is sorted and we can do a binary
 256      * search. For now stick to a linear search.
 257      */
 258
 259     for (atbl = adb->tbl, i = 0; i < adb->tblcount; i++, atbl++)
 260         if (atbl->value == selector)
 261             return &atbl->tt;
 262
 263     /* FIXME: need to search application table too */
 264
 265     /* No match, return default type */
 266     if (!adb->default_tt)
 267         goto err;
 268     return adb->default_tt;
 269
 270  err:
 271     /* FIXME: should log the value or OID of unsupported type */
 272     if (nullerr)
 273         ASN1err(ASN1_F_ASN1_DO_ADB, ASN1_R_UNSUPPORTED_ANY_DEFINED_BY_TYPE);
 274     return NULL;
 275 }