1 /* 2 * Copyright 2000-2021 The OpenSSL Project Authors. All Rights Reserved. 3 * 4 * Licensed under the Apache License 2.0 (the "License"). You may not use 5 * this file except in compliance with the License. You can obtain a copy 6 * in the file LICENSE in the source distribution or at 7 * https://www.openssl.org/source/license.html 8 */ 9 10 #include <stddef.h> 11 #include <string.h> 12 #include "internal/cryptlib.h" 13 #include "internal/refcount.h" 14 #include <openssl/asn1.h> 15 #include <openssl/asn1t.h> 16 #include <openssl/objects.h> 17 #include <openssl/err.h> 18 #include "asn1_local.h" 19 20 /* Utility functions for manipulating fields and offsets */ 21 22 /* Add 'offset' to 'addr' */ 23 #define offset2ptr(addr, offset) (void *)(((char *) addr) + offset) 24 25 /* 26 * Given an ASN1_ITEM CHOICE type return the selector value 27 */ 28 29 int ossl_asn1_get_choice_selector(ASN1_VALUE **pval, const ASN1_ITEM *it) 30 { 31 int *sel = offset2ptr(*pval, it->utype); 32 33 return *sel; 34 } 35 36 int ossl_asn1_get_choice_selector_const(const ASN1_VALUE **pval, 37 const ASN1_ITEM *it) 38 { 39 int *sel = offset2ptr(*pval, it->utype); 40 41 return *sel; 42 } 43 44 /* 45 * Given an ASN1_ITEM CHOICE type set the selector value, return old value. 46 */ 47 48 int ossl_asn1_set_choice_selector(ASN1_VALUE **pval, int value, 49 const ASN1_ITEM *it) 50 { 51 int *sel, ret; 52 53 sel = offset2ptr(*pval, it->utype); 54 ret = *sel; 55 *sel = value; 56 return ret; 57 } 58 59 /* 60 * Do atomic reference counting. The value 'op' decides what to do. 61 * If it is +1 then the count is incremented. 62 * If |op| is 0, lock is initialised and count is set to 1. 63 * If |op| is -1, count is decremented and the return value is the current 64 * reference count or 0 if no reference count is active. 65 * It returns -1 on initialisation error. 66 * Used by ASN1_SEQUENCE construct of X509, X509_REQ, X509_CRL objects 67 */ 68 int ossl_asn1_do_lock(ASN1_VALUE **pval, int op, const ASN1_ITEM *it) 69 { 70 const ASN1_AUX *aux; 71 CRYPTO_REF_COUNT *lck; 72 CRYPTO_RWLOCK **lock; 73 int ret = -1; 74 75 if ((it->itype != ASN1_ITYPE_SEQUENCE) 76 && (it->itype != ASN1_ITYPE_NDEF_SEQUENCE)) 77 return 0; 78 aux = it->funcs; 79 if (aux == NULL || (aux->flags & ASN1_AFLG_REFCOUNT) == 0) 80 return 0; 81 lck = offset2ptr(*pval, aux->ref_offset); 82 lock = offset2ptr(*pval, aux->ref_lock); 83 84 switch (op) { 85 case 0: 86 *lck = ret = 1; 87 *lock = CRYPTO_THREAD_lock_new(); 88 if (*lock == NULL) { 89 ERR_raise(ERR_LIB_ASN1, ERR_R_MALLOC_FAILURE); 90 return -1; 91 } 92 break; 93 case 1: 94 if (!CRYPTO_UP_REF(lck, &ret, *lock)) 95 return -1; 96 break; 97 case -1: 98 if (!CRYPTO_DOWN_REF(lck, &ret, *lock)) 99 return -1; /* failed */ 100 REF_PRINT_EX(it->sname, ret, (void *)it); 101 REF_ASSERT_ISNT(ret < 0); 102 if (ret == 0) { 103 CRYPTO_THREAD_lock_free(*lock); 104 *lock = NULL; 105 } 106 break; 107 } 108 109 return ret; 110 } 111 112 static ASN1_ENCODING *asn1_get_enc_ptr(ASN1_VALUE **pval, const ASN1_ITEM *it) 113 { 114 const ASN1_AUX *aux; 115 116 if (pval == NULL || *pval == NULL) 117 return NULL; 118 aux = it->funcs; 119 if (aux == NULL || (aux->flags & ASN1_AFLG_ENCODING) == 0) 120 return NULL; 121 return offset2ptr(*pval, aux->enc_offset); 122 } 123 124 static const ASN1_ENCODING *asn1_get_const_enc_ptr(const ASN1_VALUE **pval, 125 const ASN1_ITEM *it) 126 { 127 const ASN1_AUX *aux; 128 129 if (pval == NULL || *pval == NULL) 130 return NULL; 131 aux = it->funcs; 132 if (aux == NULL || (aux->flags & ASN1_AFLG_ENCODING) == 0) 133 return NULL; 134 return offset2ptr(*pval, aux->enc_offset); 135 } 136 137 void ossl_asn1_enc_init(ASN1_VALUE **pval, const ASN1_ITEM *it) 138 { 139 ASN1_ENCODING *enc = asn1_get_enc_ptr(pval, it); 140 141 if (enc != NULL) { 142 enc->enc = NULL; 143 enc->len = 0; 144 enc->modified = 1; 145 } 146 } 147 148 void ossl_asn1_enc_free(ASN1_VALUE **pval, const ASN1_ITEM *it) 149 { 150 ASN1_ENCODING *enc = asn1_get_enc_ptr(pval, it); 151 152 if (enc != NULL) { 153 OPENSSL_free(enc->enc); 154 enc->enc = NULL; 155 enc->len = 0; 156 enc->modified = 1; 157 } 158 } 159 160 int ossl_asn1_enc_save(ASN1_VALUE **pval, const unsigned char *in, int inlen, 161 const ASN1_ITEM *it) 162 { 163 ASN1_ENCODING *enc = asn1_get_enc_ptr(pval, it); 164 165 if (enc == NULL) 166 return 1; 167 168 OPENSSL_free(enc->enc); 169 if (inlen <= 0) 170 return 0; 171 if ((enc->enc = OPENSSL_malloc(inlen)) == NULL) { 172 ERR_raise(ERR_LIB_ASN1, ERR_R_MALLOC_FAILURE); 173 return 0; 174 } 175 memcpy(enc->enc, in, inlen); 176 enc->len = inlen; 177 enc->modified = 0; 178 179 return 1; 180 } 181 182 int ossl_asn1_enc_restore(int *len, unsigned char **out, const ASN1_VALUE **pval, 183 const ASN1_ITEM *it) 184 { 185 const ASN1_ENCODING *enc = asn1_get_const_enc_ptr(pval, it); 186 187 if (enc == NULL || enc->modified) 188 return 0; 189 if (out) { 190 memcpy(*out, enc->enc, enc->len); 191 *out += enc->len; 192 } 193 if (len != NULL) 194 *len = enc->len; 195 return 1; 196 } 197 198 /* Given an ASN1_TEMPLATE get a pointer to a field */ 199 ASN1_VALUE **ossl_asn1_get_field_ptr(ASN1_VALUE **pval, const ASN1_TEMPLATE *tt) 200 { 201 ASN1_VALUE **pvaltmp = offset2ptr(*pval, tt->offset); 202 203 /* 204 * NOTE for BOOLEAN types the field is just a plain int so we can't 205 * return int **, so settle for (int *). 206 */ 207 return pvaltmp; 208 } 209 210 /* Given an ASN1_TEMPLATE get a const pointer to a field */ 211 const ASN1_VALUE **ossl_asn1_get_const_field_ptr(const ASN1_VALUE **pval, 212 const ASN1_TEMPLATE *tt) 213 { 214 return offset2ptr(*pval, tt->offset); 215 } 216 217 /* 218 * Handle ANY DEFINED BY template, find the selector, look up the relevant 219 * ASN1_TEMPLATE in the table and return it. 220 */ 221 222 const ASN1_TEMPLATE *ossl_asn1_do_adb(const ASN1_VALUE *val, 223 const ASN1_TEMPLATE *tt, 224 int nullerr) 225 { 226 const ASN1_ADB *adb; 227 const ASN1_ADB_TABLE *atbl; 228 long selector; 229 const ASN1_VALUE **sfld; 230 int i; 231 232 if ((tt->flags & ASN1_TFLG_ADB_MASK) == 0) 233 return tt; 234 235 /* Else ANY DEFINED BY ... get the table */ 236 adb = ASN1_ADB_ptr(tt->item); 237 238 /* Get the selector field */ 239 sfld = offset2ptr(val, adb->offset); 240 241 /* Check if NULL */ 242 if (*sfld == NULL) { 243 if (adb->null_tt == NULL) 244 goto err; 245 return adb->null_tt; 246 } 247 248 /* 249 * Convert type to a long: NB: don't check for NID_undef here because it 250 * might be a legitimate value in the table 251 */ 252 if ((tt->flags & ASN1_TFLG_ADB_OID) != 0) 253 selector = OBJ_obj2nid((ASN1_OBJECT *)*sfld); 254 else 255 selector = ASN1_INTEGER_get((ASN1_INTEGER *)*sfld); 256 257 /* Let application callback translate value */ 258 if (adb->adb_cb != NULL && adb->adb_cb(&selector) == 0) { 259 ERR_raise(ERR_LIB_ASN1, ASN1_R_UNSUPPORTED_ANY_DEFINED_BY_TYPE); 260 return NULL; 261 } 262 263 /* 264 * Try to find matching entry in table Maybe should check application 265 * types first to allow application override? Might also be useful to 266 * have a flag which indicates table is sorted and we can do a binary 267 * search. For now stick to a linear search. 268 */ 269 270 for (atbl = adb->tbl, i = 0; i < adb->tblcount; i++, atbl++) 271 if (atbl->value == selector) 272 return &atbl->tt; 273 274 /* FIXME: need to search application table too */ 275 276 /* No match, return default type */ 277 if (!adb->default_tt) 278 goto err; 279 return adb->default_tt; 280 281 err: 282 /* FIXME: should log the value or OID of unsupported type */ 283 if (nullerr) 284 ERR_raise(ERR_LIB_ASN1, ASN1_R_UNSUPPORTED_ANY_DEFINED_BY_TYPE); 285 return NULL; 286 } 287