diff options
Diffstat (limited to 'library/x509_create.c')
| -rw-r--r-- | library/x509_create.c | 374 |
1 files changed, 374 insertions, 0 deletions
diff --git a/library/x509_create.c b/library/x509_create.c new file mode 100644 index 000000000..056bbaa78 --- /dev/null +++ b/library/x509_create.c @@ -0,0 +1,374 @@ +/* + * 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 */ |