1 // SPDX-License-Identifier: Apache-2.0 2 /* 3 * X.509 base functions for creating certificates / CSRs 4 * 5 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved 6 * 7 * Licensed under the Apache License, Version 2.0 (the "License"); you may 8 * not use this file except in compliance with the License. 9 * You may obtain a copy of the License at 10 * 11 * http://www.apache.org/licenses/LICENSE-2.0 12 * 13 * Unless required by applicable law or agreed to in writing, software 14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 16 * See the License for the specific language governing permissions and 17 * limitations under the License. 18 * 19 * This file is part of mbed TLS (https://tls.mbed.org) 20 */ 21 22 #if !defined(MBEDTLS_CONFIG_FILE) 23 #include "mbedtls/config.h" 24 #else 25 #include MBEDTLS_CONFIG_FILE 26 #endif 27 28 #if defined(MBEDTLS_X509_CREATE_C) 29 30 #include "mbedtls/x509.h" 31 #include "mbedtls/asn1write.h" 32 #include "mbedtls/error.h" 33 #include "mbedtls/oid.h" 34 35 #include <string.h> 36 37 /* Structure linking OIDs for X.509 DN AttributeTypes to their 38 * string representations and default string encodings used by Mbed TLS. */ 39 typedef struct { 40 const char *name; /* String representation of AttributeType, e.g. 41 * "CN" or "emailAddress". */ 42 size_t name_len; /* Length of 'name', without trailing 0 byte. */ 43 const char *oid; /* String representation of OID of AttributeType, 44 * as per RFC 5280, Appendix A.1. */ 45 int default_tag; /* The default character encoding used for the 46 * given attribute type, e.g. 47 * MBEDTLS_ASN1_UTF8_STRING for UTF-8. */ 48 } x509_attr_descriptor_t; 49 50 #define ADD_STRLEN( s ) s, sizeof( s ) - 1 51 52 /* X.509 DN attributes from RFC 5280, Appendix A.1. */ 53 static const x509_attr_descriptor_t x509_attrs[] = 54 { 55 { ADD_STRLEN( "CN" ), 56 MBEDTLS_OID_AT_CN, MBEDTLS_ASN1_UTF8_STRING }, 57 { ADD_STRLEN( "commonName" ), 58 MBEDTLS_OID_AT_CN, MBEDTLS_ASN1_UTF8_STRING }, 59 { ADD_STRLEN( "C" ), 60 MBEDTLS_OID_AT_COUNTRY, MBEDTLS_ASN1_PRINTABLE_STRING }, 61 { ADD_STRLEN( "countryName" ), 62 MBEDTLS_OID_AT_COUNTRY, MBEDTLS_ASN1_PRINTABLE_STRING }, 63 { ADD_STRLEN( "O" ), 64 MBEDTLS_OID_AT_ORGANIZATION, MBEDTLS_ASN1_UTF8_STRING }, 65 { ADD_STRLEN( "organizationName" ), 66 MBEDTLS_OID_AT_ORGANIZATION, MBEDTLS_ASN1_UTF8_STRING }, 67 { ADD_STRLEN( "L" ), 68 MBEDTLS_OID_AT_LOCALITY, MBEDTLS_ASN1_UTF8_STRING }, 69 { ADD_STRLEN( "locality" ), 70 MBEDTLS_OID_AT_LOCALITY, MBEDTLS_ASN1_UTF8_STRING }, 71 { ADD_STRLEN( "R" ), 72 MBEDTLS_OID_PKCS9_EMAIL, MBEDTLS_ASN1_IA5_STRING }, 73 { ADD_STRLEN( "OU" ), 74 MBEDTLS_OID_AT_ORG_UNIT, MBEDTLS_ASN1_UTF8_STRING }, 75 { ADD_STRLEN( "organizationalUnitName" ), 76 MBEDTLS_OID_AT_ORG_UNIT, MBEDTLS_ASN1_UTF8_STRING }, 77 { ADD_STRLEN( "ST" ), 78 MBEDTLS_OID_AT_STATE, MBEDTLS_ASN1_UTF8_STRING }, 79 { ADD_STRLEN( "stateOrProvinceName" ), 80 MBEDTLS_OID_AT_STATE, MBEDTLS_ASN1_UTF8_STRING }, 81 { ADD_STRLEN( "emailAddress" ), 82 MBEDTLS_OID_PKCS9_EMAIL, MBEDTLS_ASN1_IA5_STRING }, 83 { ADD_STRLEN( "serialNumber" ), 84 MBEDTLS_OID_AT_SERIAL_NUMBER, MBEDTLS_ASN1_PRINTABLE_STRING }, 85 { ADD_STRLEN( "postalAddress" ), 86 MBEDTLS_OID_AT_POSTAL_ADDRESS, MBEDTLS_ASN1_PRINTABLE_STRING }, 87 { ADD_STRLEN( "postalCode" ), 88 MBEDTLS_OID_AT_POSTAL_CODE, MBEDTLS_ASN1_PRINTABLE_STRING }, 89 { ADD_STRLEN( "dnQualifier" ), 90 MBEDTLS_OID_AT_DN_QUALIFIER, MBEDTLS_ASN1_PRINTABLE_STRING }, 91 { ADD_STRLEN( "title" ), 92 MBEDTLS_OID_AT_TITLE, MBEDTLS_ASN1_UTF8_STRING }, 93 { ADD_STRLEN( "surName" ), 94 MBEDTLS_OID_AT_SUR_NAME, MBEDTLS_ASN1_UTF8_STRING }, 95 { ADD_STRLEN( "SN" ), 96 MBEDTLS_OID_AT_SUR_NAME, MBEDTLS_ASN1_UTF8_STRING }, 97 { ADD_STRLEN( "givenName" ), 98 MBEDTLS_OID_AT_GIVEN_NAME, MBEDTLS_ASN1_UTF8_STRING }, 99 { ADD_STRLEN( "GN" ), 100 MBEDTLS_OID_AT_GIVEN_NAME, MBEDTLS_ASN1_UTF8_STRING }, 101 { ADD_STRLEN( "initials" ), 102 MBEDTLS_OID_AT_INITIALS, MBEDTLS_ASN1_UTF8_STRING }, 103 { ADD_STRLEN( "pseudonym" ), 104 MBEDTLS_OID_AT_PSEUDONYM, MBEDTLS_ASN1_UTF8_STRING }, 105 { ADD_STRLEN( "generationQualifier" ), 106 MBEDTLS_OID_AT_GENERATION_QUALIFIER, MBEDTLS_ASN1_UTF8_STRING }, 107 { ADD_STRLEN( "domainComponent" ), 108 MBEDTLS_OID_DOMAIN_COMPONENT, MBEDTLS_ASN1_IA5_STRING }, 109 { ADD_STRLEN( "DC" ), 110 MBEDTLS_OID_DOMAIN_COMPONENT, MBEDTLS_ASN1_IA5_STRING }, 111 { NULL, 0, NULL, MBEDTLS_ASN1_NULL } 112 }; 113 114 static const x509_attr_descriptor_t *x509_attr_descr_from_name( const char *name, size_t name_len ) 115 { 116 const x509_attr_descriptor_t *cur; 117 118 for( cur = x509_attrs; cur->name != NULL; cur++ ) 119 if( cur->name_len == name_len && 120 strncmp( cur->name, name, name_len ) == 0 ) 121 break; 122 123 if ( cur->name == NULL ) 124 return( NULL ); 125 126 return( cur ); 127 } 128 129 int mbedtls_x509_string_to_names( mbedtls_asn1_named_data **head, const char *name ) 130 { 131 int ret = 0; 132 const char *s = name, *c = s; 133 const char *end = s + strlen( s ); 134 const char *oid = NULL; 135 const x509_attr_descriptor_t* attr_descr = NULL; 136 int in_tag = 1; 137 char data[MBEDTLS_X509_MAX_DN_NAME_SIZE]; 138 char *d = data; 139 140 /* Clear existing chain if present */ 141 mbedtls_asn1_free_named_data_list( head ); 142 143 while( c <= end ) 144 { 145 if( in_tag && *c == '=' ) 146 { 147 if( ( attr_descr = x509_attr_descr_from_name( s, c - s ) ) == NULL ) 148 { 149 ret = MBEDTLS_ERR_X509_UNKNOWN_OID; 150 goto exit; 151 } 152 153 oid = attr_descr->oid; 154 s = c + 1; 155 in_tag = 0; 156 d = data; 157 } 158 159 if( !in_tag && *c == '\\' && c != end ) 160 { 161 c++; 162 163 /* Check for valid escaped characters */ 164 if( c == end || *c != ',' ) 165 { 166 ret = MBEDTLS_ERR_X509_INVALID_NAME; 167 goto exit; 168 } 169 } 170 else if( !in_tag && ( *c == ',' || c == end ) ) 171 { 172 mbedtls_asn1_named_data* cur = 173 mbedtls_asn1_store_named_data( head, oid, strlen( oid ), 174 (unsigned char *) data, 175 d - data ); 176 177 if(cur == NULL ) 178 { 179 return( MBEDTLS_ERR_X509_ALLOC_FAILED ); 180 } 181 182 // set tagType 183 cur->val.tag = attr_descr->default_tag; 184 185 while( c < end && *(c + 1) == ' ' ) 186 c++; 187 188 s = c + 1; 189 in_tag = 1; 190 } 191 192 if( !in_tag && s != c + 1 ) 193 { 194 *(d++) = *c; 195 196 if( d - data == MBEDTLS_X509_MAX_DN_NAME_SIZE ) 197 { 198 ret = MBEDTLS_ERR_X509_INVALID_NAME; 199 goto exit; 200 } 201 } 202 203 c++; 204 } 205 206 exit: 207 208 return( ret ); 209 } 210 211 /* The first byte of the value in the mbedtls_asn1_named_data structure is reserved 212 * to store the critical boolean for us 213 */ 214 int mbedtls_x509_set_extension( mbedtls_asn1_named_data **head, const char *oid, size_t oid_len, 215 int critical, const unsigned char *val, size_t val_len ) 216 { 217 mbedtls_asn1_named_data *cur; 218 219 if( ( cur = mbedtls_asn1_store_named_data( head, oid, oid_len, 220 NULL, val_len + 1 ) ) == NULL ) 221 { 222 return( MBEDTLS_ERR_X509_ALLOC_FAILED ); 223 } 224 225 cur->val.p[0] = critical; 226 memcpy( cur->val.p + 1, val, val_len ); 227 228 return( 0 ); 229 } 230 231 /* 232 * RelativeDistinguishedName ::= 233 * SET OF AttributeTypeAndValue 234 * 235 * AttributeTypeAndValue ::= SEQUENCE { 236 * type AttributeType, 237 * value AttributeValue } 238 * 239 * AttributeType ::= OBJECT IDENTIFIER 240 * 241 * AttributeValue ::= ANY DEFINED BY AttributeType 242 */ 243 static int x509_write_name( unsigned char **p, unsigned char *start, mbedtls_asn1_named_data* cur_name) 244 { 245 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; 246 size_t len = 0; 247 const char *oid = (const char*)cur_name->oid.p; 248 size_t oid_len = cur_name->oid.len; 249 const unsigned char *name = cur_name->val.p; 250 size_t name_len = cur_name->val.len; 251 252 // Write correct string tag and value 253 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tagged_string( p, start, 254 cur_name->val.tag, 255 (const char *) name, 256 name_len ) ); 257 // Write OID 258 // 259 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_oid( p, start, oid, 260 oid_len ) ); 261 262 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) ); 263 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, 264 MBEDTLS_ASN1_CONSTRUCTED | 265 MBEDTLS_ASN1_SEQUENCE ) ); 266 267 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) ); 268 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, 269 MBEDTLS_ASN1_CONSTRUCTED | 270 MBEDTLS_ASN1_SET ) ); 271 272 return( (int) len ); 273 } 274 275 int mbedtls_x509_write_names( unsigned char **p, unsigned char *start, 276 mbedtls_asn1_named_data *first ) 277 { 278 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; 279 size_t len = 0; 280 mbedtls_asn1_named_data *cur = first; 281 282 while( cur != NULL ) 283 { 284 MBEDTLS_ASN1_CHK_ADD( len, x509_write_name( p, start, cur ) ); 285 cur = cur->next; 286 } 287 288 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) ); 289 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_CONSTRUCTED | 290 MBEDTLS_ASN1_SEQUENCE ) ); 291 292 return( (int) len ); 293 } 294 295 int mbedtls_x509_write_sig( unsigned char **p, unsigned char *start, 296 const char *oid, size_t oid_len, 297 unsigned char *sig, size_t size ) 298 { 299 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; 300 size_t len = 0; 301 302 if( *p < start || (size_t)( *p - start ) < size ) 303 return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL ); 304 305 len = size; 306 (*p) -= len; 307 memcpy( *p, sig, len ); 308 309 if( *p - start < 1 ) 310 return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL ); 311 312 *--(*p) = 0; 313 len += 1; 314 315 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) ); 316 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_BIT_STRING ) ); 317 318 // Write OID 319 // 320 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_algorithm_identifier( p, start, oid, 321 oid_len, 0 ) ); 322 323 return( (int) len ); 324 } 325 326 static int x509_write_extension( unsigned char **p, unsigned char *start, 327 mbedtls_asn1_named_data *ext ) 328 { 329 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; 330 size_t len = 0; 331 332 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_raw_buffer( p, start, ext->val.p + 1, 333 ext->val.len - 1 ) ); 334 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, ext->val.len - 1 ) ); 335 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_OCTET_STRING ) ); 336 337 if( ext->val.p[0] != 0 ) 338 { 339 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_bool( p, start, 1 ) ); 340 } 341 342 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_raw_buffer( p, start, ext->oid.p, 343 ext->oid.len ) ); 344 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, ext->oid.len ) ); 345 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_OID ) ); 346 347 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) ); 348 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_CONSTRUCTED | 349 MBEDTLS_ASN1_SEQUENCE ) ); 350 351 return( (int) len ); 352 } 353 354 /* 355 * Extension ::= SEQUENCE { 356 * extnID OBJECT IDENTIFIER, 357 * critical BOOLEAN DEFAULT FALSE, 358 * extnValue OCTET STRING 359 * -- contains the DER encoding of an ASN.1 value 360 * -- corresponding to the extension type identified 361 * -- by extnID 362 * } 363 */ 364 int mbedtls_x509_write_extensions( unsigned char **p, unsigned char *start, 365 mbedtls_asn1_named_data *first ) 366 { 367 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; 368 size_t len = 0; 369 mbedtls_asn1_named_data *cur_ext = first; 370 371 while( cur_ext != NULL ) 372 { 373 MBEDTLS_ASN1_CHK_ADD( len, x509_write_extension( p, start, cur_ext ) ); 374 cur_ext = cur_ext->next; 375 } 376 377 return( (int) len ); 378 } 379 380 #endif /* MBEDTLS_X509_CREATE_C */ 381