/* * X.509 base functions for creating certificates / CSRs * * Copyright The Mbed TLS Contributors * SPDX-License-Identifier: Apache-2.0 * * Licensed under the Apache License, Version 2.0 (the "License"); you may * not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include "common.h" #if defined(MBEDTLS_X509_CREATE_C) #include "mbedtls/x509.h" #include "mbedtls/asn1write.h" #include "mbedtls/error.h" #include "mbedtls/oid.h" #include <string.h> /* Structure linking OIDs for X.509 DN AttributeTypes to their * string representations and default string encodings used by Mbed TLS. */ typedef struct { const char *name; /* String representation of AttributeType, e.g. * "CN" or "emailAddress". */ size_t name_len; /* Length of 'name', without trailing 0 byte. */ const char *oid; /* String representation of OID of AttributeType, * as per RFC 5280, Appendix A.1. */ int default_tag; /* The default character encoding used for the * given attribute type, e.g. * MBEDTLS_ASN1_UTF8_STRING for UTF-8. */ } x509_attr_descriptor_t; #define ADD_STRLEN( s ) s, sizeof( s ) - 1 /* X.509 DN attributes from RFC 5280, Appendix A.1. */ static const x509_attr_descriptor_t x509_attrs[] = { { ADD_STRLEN( "CN" ), MBEDTLS_OID_AT_CN, MBEDTLS_ASN1_UTF8_STRING }, { ADD_STRLEN( "commonName" ), MBEDTLS_OID_AT_CN, MBEDTLS_ASN1_UTF8_STRING }, { ADD_STRLEN( "C" ), MBEDTLS_OID_AT_COUNTRY, MBEDTLS_ASN1_PRINTABLE_STRING }, { ADD_STRLEN( "countryName" ), MBEDTLS_OID_AT_COUNTRY, MBEDTLS_ASN1_PRINTABLE_STRING }, { ADD_STRLEN( "O" ), MBEDTLS_OID_AT_ORGANIZATION, MBEDTLS_ASN1_UTF8_STRING }, { ADD_STRLEN( "organizationName" ), MBEDTLS_OID_AT_ORGANIZATION, MBEDTLS_ASN1_UTF8_STRING }, { ADD_STRLEN( "L" ), MBEDTLS_OID_AT_LOCALITY, MBEDTLS_ASN1_UTF8_STRING }, { ADD_STRLEN( "locality" ), MBEDTLS_OID_AT_LOCALITY, MBEDTLS_ASN1_UTF8_STRING }, { ADD_STRLEN( "R" ), MBEDTLS_OID_PKCS9_EMAIL, MBEDTLS_ASN1_IA5_STRING }, { ADD_STRLEN( "OU" ), MBEDTLS_OID_AT_ORG_UNIT, MBEDTLS_ASN1_UTF8_STRING }, { ADD_STRLEN( "organizationalUnitName" ), MBEDTLS_OID_AT_ORG_UNIT, MBEDTLS_ASN1_UTF8_STRING }, { ADD_STRLEN( "ST" ), MBEDTLS_OID_AT_STATE, MBEDTLS_ASN1_UTF8_STRING }, { ADD_STRLEN( "stateOrProvinceName" ), MBEDTLS_OID_AT_STATE, MBEDTLS_ASN1_UTF8_STRING }, { ADD_STRLEN( "emailAddress" ), MBEDTLS_OID_PKCS9_EMAIL, MBEDTLS_ASN1_IA5_STRING }, { ADD_STRLEN( "serialNumber" ), MBEDTLS_OID_AT_SERIAL_NUMBER, MBEDTLS_ASN1_PRINTABLE_STRING }, { ADD_STRLEN( "postalAddress" ), MBEDTLS_OID_AT_POSTAL_ADDRESS, MBEDTLS_ASN1_PRINTABLE_STRING }, { ADD_STRLEN( "postalCode" ), MBEDTLS_OID_AT_POSTAL_CODE, MBEDTLS_ASN1_PRINTABLE_STRING }, { ADD_STRLEN( "dnQualifier" ), MBEDTLS_OID_AT_DN_QUALIFIER, MBEDTLS_ASN1_PRINTABLE_STRING }, { ADD_STRLEN( "title" ), MBEDTLS_OID_AT_TITLE, MBEDTLS_ASN1_UTF8_STRING }, { ADD_STRLEN( "surName" ), MBEDTLS_OID_AT_SUR_NAME, MBEDTLS_ASN1_UTF8_STRING }, { ADD_STRLEN( "SN" ), MBEDTLS_OID_AT_SUR_NAME, MBEDTLS_ASN1_UTF8_STRING }, { ADD_STRLEN( "givenName" ), MBEDTLS_OID_AT_GIVEN_NAME, MBEDTLS_ASN1_UTF8_STRING }, { ADD_STRLEN( "GN" ), MBEDTLS_OID_AT_GIVEN_NAME, MBEDTLS_ASN1_UTF8_STRING }, { ADD_STRLEN( "initials" ), MBEDTLS_OID_AT_INITIALS, MBEDTLS_ASN1_UTF8_STRING }, { ADD_STRLEN( "pseudonym" ), MBEDTLS_OID_AT_PSEUDONYM, MBEDTLS_ASN1_UTF8_STRING }, { ADD_STRLEN( "generationQualifier" ), MBEDTLS_OID_AT_GENERATION_QUALIFIER, MBEDTLS_ASN1_UTF8_STRING }, { ADD_STRLEN( "domainComponent" ), MBEDTLS_OID_DOMAIN_COMPONENT, MBEDTLS_ASN1_IA5_STRING }, { ADD_STRLEN( "DC" ), MBEDTLS_OID_DOMAIN_COMPONENT, MBEDTLS_ASN1_IA5_STRING }, { NULL, 0, NULL, MBEDTLS_ASN1_NULL } }; static const x509_attr_descriptor_t *x509_attr_descr_from_name( const char *name, size_t name_len ) { const x509_attr_descriptor_t *cur; for( cur = x509_attrs; cur->name != NULL; cur++ ) if( cur->name_len == name_len && strncmp( cur->name, name, name_len ) == 0 ) break; if ( cur->name == NULL ) return( NULL ); return( cur ); } int mbedtls_x509_string_to_names( mbedtls_asn1_named_data **head, const char *name ) { int ret = 0; const char *s = name, *c = s; const char *end = s + strlen( s ); const char *oid = NULL; const x509_attr_descriptor_t* attr_descr = NULL; int in_tag = 1; char data[MBEDTLS_X509_MAX_DN_NAME_SIZE]; char *d = data; /* Clear existing chain if present */ mbedtls_asn1_free_named_data_list( head ); while( c <= end ) { if( in_tag && *c == '=' ) { if( ( attr_descr = x509_attr_descr_from_name( s, c - s ) ) == NULL ) { ret = MBEDTLS_ERR_X509_UNKNOWN_OID; goto exit; } oid = attr_descr->oid; s = c + 1; in_tag = 0; d = data; } if( !in_tag && *c == '\\' && c != end ) { c++; /* Check for valid escaped characters */ if( c == end || *c != ',' ) { ret = MBEDTLS_ERR_X509_INVALID_NAME; goto exit; } } else if( !in_tag && ( *c == ',' || c == end ) ) { mbedtls_asn1_named_data* cur = mbedtls_asn1_store_named_data( head, oid, strlen( oid ), (unsigned char *) data, d - data ); if(cur == NULL ) { return( MBEDTLS_ERR_X509_ALLOC_FAILED ); } // set tagType cur->val.tag = attr_descr->default_tag; while( c < end && *(c + 1) == ' ' ) c++; s = c + 1; in_tag = 1; } if( !in_tag && s != c + 1 ) { *(d++) = *c; if( d - data == MBEDTLS_X509_MAX_DN_NAME_SIZE ) { ret = MBEDTLS_ERR_X509_INVALID_NAME; goto exit; } } c++; } exit: return( ret ); } /* The first byte of the value in the mbedtls_asn1_named_data structure is reserved * to store the critical boolean for us */ int mbedtls_x509_set_extension( mbedtls_asn1_named_data **head, const char *oid, size_t oid_len, int critical, const unsigned char *val, size_t val_len ) { mbedtls_asn1_named_data *cur; if( ( cur = mbedtls_asn1_store_named_data( head, oid, oid_len, NULL, val_len + 1 ) ) == NULL ) { return( MBEDTLS_ERR_X509_ALLOC_FAILED ); } cur->val.p[0] = critical; memcpy( cur->val.p + 1, val, val_len ); return( 0 ); } /* * RelativeDistinguishedName ::= * SET OF AttributeTypeAndValue * * AttributeTypeAndValue ::= SEQUENCE { * type AttributeType, * value AttributeValue } * * AttributeType ::= OBJECT IDENTIFIER * * AttributeValue ::= ANY DEFINED BY AttributeType */ static int x509_write_name( unsigned char **p, unsigned char *start, mbedtls_asn1_named_data* cur_name) { int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; size_t len = 0; const char *oid = (const char*)cur_name->oid.p; size_t oid_len = cur_name->oid.len; const unsigned char *name = cur_name->val.p; size_t name_len = cur_name->val.len; // Write correct string tag and value MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tagged_string( p, start, cur_name->val.tag, (const char *) name, name_len ) ); // Write OID // MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_oid( p, start, oid, oid_len ) ); MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) ); MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ); MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) ); MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SET ) ); return( (int) len ); } int mbedtls_x509_write_names( unsigned char **p, unsigned char *start, mbedtls_asn1_named_data *first ) { int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; size_t len = 0; mbedtls_asn1_named_data *cur = first; while( cur != NULL ) { MBEDTLS_ASN1_CHK_ADD( len, x509_write_name( p, start, cur ) ); cur = cur->next; } MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) ); MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ); return( (int) len ); } int mbedtls_x509_write_sig( unsigned char **p, unsigned char *start, const char *oid, size_t oid_len, unsigned char *sig, size_t size ) { int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; size_t len = 0; if( *p < start || (size_t)( *p - start ) < size ) return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL ); len = size; (*p) -= len; memcpy( *p, sig, len ); if( *p - start < 1 ) return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL ); *--(*p) = 0; len += 1; MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) ); MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_BIT_STRING ) ); // Write OID // MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_algorithm_identifier( p, start, oid, oid_len, 0 ) ); return( (int) len ); } static int x509_write_extension( unsigned char **p, unsigned char *start, mbedtls_asn1_named_data *ext ) { int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; size_t len = 0; MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_raw_buffer( p, start, ext->val.p + 1, ext->val.len - 1 ) ); MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, ext->val.len - 1 ) ); MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_OCTET_STRING ) ); if( ext->val.p[0] != 0 ) { MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_bool( p, start, 1 ) ); } MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_raw_buffer( p, start, ext->oid.p, ext->oid.len ) ); MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, ext->oid.len ) ); MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_OID ) ); MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) ); MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ); return( (int) len ); } /* * Extension ::= SEQUENCE { * extnID OBJECT IDENTIFIER, * critical BOOLEAN DEFAULT FALSE, * extnValue OCTET STRING * -- contains the DER encoding of an ASN.1 value * -- corresponding to the extension type identified * -- by extnID * } */ int mbedtls_x509_write_extensions( unsigned char **p, unsigned char *start, mbedtls_asn1_named_data *first ) { int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; size_t len = 0; mbedtls_asn1_named_data *cur_ext = first; while( cur_ext != NULL ) { MBEDTLS_ASN1_CHK_ADD( len, x509_write_extension( p, start, cur_ext ) ); cur_ext = cur_ext->next; } return( (int) len ); } #endif /* MBEDTLS_X509_CREATE_C */