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