int mbedtls_ecies_write_kdf(unsigned char **p, unsigned char *start,
mbedtls_kdf_type_t kdf_type, mbedtls_md_type_t md_type)
{
int result = 0;
int len = 0;
size_t md_par_len = 0;
size_t kdf_par_len = 0;
const char *oid = NULL;
size_t oid_len = 0;
if (kdf_type == MBEDTLS_KDF_NONE || md_type == MBEDTLS_MD_NONE)
{
return MBEDTLS_ERR_ECIES_BAD_INPUT_DATA;
}
ACCUMULATE_AND_CHECK(result, md_par_len,
mbedtls_asn1_write_null(p, start)
);
INVOKE_AND_CHECK(result,
mbedtls_oid_get_oid_by_md(md_type, &oid, &oid_len)
);
ACCUMULATE_AND_CHECK(result, kdf_par_len,
mbedtls_asn1_write_algorithm_identifier(p, start, oid, oid_len, md_par_len)
);
INVOKE_AND_CHECK(result,
mbedtls_oid_get_oid_by_kdf_alg(kdf_type, &oid, &oid_len)
);
ACCUMULATE_AND_CHECK(result, len,
mbedtls_asn1_write_algorithm_identifier(p, start, oid, oid_len, kdf_par_len)
);
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;
size_t len = 0;
if( *p - start < (int) size + 1 )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
len = size;
(*p) -= len;
memcpy( *p, sig, len );
*--(*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 );
}
int mbedtls_ecies_write_hmac(unsigned char **p, unsigned char *start,
mbedtls_md_type_t hmac_type, const unsigned char *hmac, size_t hmac_len)
{
int result = 0;
size_t len = 0;
size_t par_len = 0;
const char *oid = NULL;
size_t oid_len = 0;
if (hmac_type == MBEDTLS_MD_NONE || hmac == NULL || hmac_len == 0)
{
return MBEDTLS_ERR_ECIES_BAD_INPUT_DATA;
}
ACCUMULATE_AND_CHECK(result, len,
mbedtls_asn1_write_octet_string(p, start, hmac, hmac_len)
);
ACCUMULATE_AND_CHECK(result, par_len,
mbedtls_asn1_write_null(p, start)
);
INVOKE_AND_CHECK(result,
mbedtls_oid_get_oid_by_md(hmac_type, &oid, &oid_len)
);
ACCUMULATE_AND_CHECK(result, len,
mbedtls_asn1_write_algorithm_identifier(p, start, oid, oid_len, par_len)
);
ACCUMULATE_AND_CHECK(result, len,
mbedtls_asn1_write_len(p, start, len)
);
ACCUMULATE_AND_CHECK(result, len,
mbedtls_asn1_write_tag(p, start, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)
);
return (int)len;
}
int mbedtls_pk_write_pubkey_der( mbedtls_pk_context *key, unsigned char *buf, size_t size )
{
int ret;
unsigned char *c;
size_t len = 0, par_len = 0, oid_len;
const char *oid;
c = buf + size;
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_pk_write_pubkey( &c, buf, key ) );
if( c - buf < 1 )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
/*
* SubjectPublicKeyInfo ::= SEQUENCE {
* algorithm AlgorithmIdentifier,
* subjectPublicKey BIT STRING }
*/
*--c = 0;
len += 1;
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, buf, len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, buf, MBEDTLS_ASN1_BIT_STRING ) );
if( ( ret = mbedtls_oid_get_oid_by_pk_alg( mbedtls_pk_get_type( key ),
&oid, &oid_len ) ) != 0 )
{
return( ret );
}
#if defined(MBEDTLS_ECP_C)
if( mbedtls_pk_get_type( key ) == MBEDTLS_PK_ECKEY )
{
MBEDTLS_ASN1_CHK_ADD( par_len, pk_write_ec_param( &c, buf, mbedtls_pk_ec( *key ) ) );
}
#endif
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_algorithm_identifier( &c, buf, oid, oid_len,
par_len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, buf, len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, buf, MBEDTLS_ASN1_CONSTRUCTED |
MBEDTLS_ASN1_SEQUENCE ) );
return( (int) len );
}
int mbedtls_ecies_write_content_info(unsigned char **p, unsigned char *start,
mbedtls_cipher_type_t cipher_type, const unsigned char *iv, size_t iv_len,
size_t data_len)
{
int result = 0;
size_t len = data_len;
size_t par_len = 0;
const char *oid = NULL;
size_t oid_len = 0;
if (cipher_type == MBEDTLS_CIPHER_NONE || iv == NULL || iv_len == 0)
{
return MBEDTLS_ERR_ECIES_BAD_INPUT_DATA;
}
ACCUMULATE_AND_CHECK(result, len,
mbedtls_asn1_write_len(p, start, data_len)
);
ACCUMULATE_AND_CHECK(result, len,
mbedtls_asn1_write_tag(p, start, MBEDTLS_ASN1_OCTET_STRING)
);
ACCUMULATE_AND_CHECK(result, par_len,
mbedtls_asn1_write_octet_string(p, start, iv, iv_len)
);
INVOKE_AND_CHECK(result,
mbedtls_oid_get_oid_by_cipher_alg(cipher_type, &oid, &oid_len)
);
ACCUMULATE_AND_CHECK(result, len,
mbedtls_asn1_write_algorithm_identifier(p, start, oid, oid_len, par_len)
);
ACCUMULATE_AND_CHECK(result, len,
mbedtls_asn1_write_len(p, start, len)
);
ACCUMULATE_AND_CHECK(result, len,
mbedtls_asn1_write_tag(p, start, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)
);
return (int)len;
}
int mbedtls_x509write_crt_der( mbedtls_x509write_cert *ctx, unsigned char *buf, size_t size,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng )
{
int ret;
const char *sig_oid;
size_t sig_oid_len = 0;
unsigned char *c, *c2;
unsigned char hash[64];
unsigned char sig[MBEDTLS_MPI_MAX_SIZE];
unsigned char tmp_buf[2048];
size_t sub_len = 0, pub_len = 0, sig_and_oid_len = 0, sig_len;
size_t len = 0;
mbedtls_pk_type_t pk_alg;
/*
* Prepare data to be signed in tmp_buf
*/
c = tmp_buf + sizeof( tmp_buf );
/* Signature algorithm needed in TBS, and later for actual signature */
pk_alg = mbedtls_pk_get_type( ctx->issuer_key );
if( pk_alg == MBEDTLS_PK_ECKEY )
pk_alg = MBEDTLS_PK_ECDSA;
if( ( ret = mbedtls_oid_get_oid_by_sig_alg( pk_alg, ctx->md_alg,
&sig_oid, &sig_oid_len ) ) != 0 )
{
return( ret );
}
/*
* Extensions ::= SEQUENCE SIZE (1..MAX) OF Extension
*/
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_x509_write_extensions( &c, tmp_buf, ctx->extensions ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, tmp_buf, len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, tmp_buf, MBEDTLS_ASN1_CONSTRUCTED |
MBEDTLS_ASN1_SEQUENCE ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, tmp_buf, len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, tmp_buf, MBEDTLS_ASN1_CONTEXT_SPECIFIC |
MBEDTLS_ASN1_CONSTRUCTED | 3 ) );
/*
* SubjectPublicKeyInfo
*/
MBEDTLS_ASN1_CHK_ADD( pub_len, mbedtls_pk_write_pubkey_der( ctx->subject_key,
tmp_buf, c - tmp_buf ) );
c -= pub_len;
len += pub_len;
/*
* Subject ::= Name
*/
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_x509_write_names( &c, tmp_buf, ctx->subject ) );
/*
* Validity ::= SEQUENCE {
* notBefore Time,
* notAfter Time }
*/
sub_len = 0;
MBEDTLS_ASN1_CHK_ADD( sub_len, x509_write_time( &c, tmp_buf, ctx->not_after,
MBEDTLS_X509_RFC5280_UTC_TIME_LEN ) );
MBEDTLS_ASN1_CHK_ADD( sub_len, x509_write_time( &c, tmp_buf, ctx->not_before,
MBEDTLS_X509_RFC5280_UTC_TIME_LEN ) );
len += sub_len;
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, tmp_buf, sub_len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, tmp_buf, MBEDTLS_ASN1_CONSTRUCTED |
MBEDTLS_ASN1_SEQUENCE ) );
/*
* Issuer ::= Name
*/
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_x509_write_names( &c, tmp_buf, ctx->issuer ) );
/*
* Signature ::= AlgorithmIdentifier
*/
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_algorithm_identifier( &c, tmp_buf,
sig_oid, strlen( sig_oid ), 0 ) );
/*
* Serial ::= INTEGER
*/
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_mpi( &c, tmp_buf, &ctx->serial ) );
/*
* Version ::= INTEGER { v1(0), v2(1), v3(2) }
*/
sub_len = 0;
MBEDTLS_ASN1_CHK_ADD( sub_len, mbedtls_asn1_write_int( &c, tmp_buf, ctx->version ) );
len += sub_len;
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, tmp_buf, sub_len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, tmp_buf, MBEDTLS_ASN1_CONTEXT_SPECIFIC |
MBEDTLS_ASN1_CONSTRUCTED | 0 ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, tmp_buf, len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, tmp_buf, MBEDTLS_ASN1_CONSTRUCTED |
MBEDTLS_ASN1_SEQUENCE ) );
/*
* Make signature
*/
mbedtls_md( mbedtls_md_info_from_type( ctx->md_alg ), c, len, hash );
if( ( ret = mbedtls_pk_sign( ctx->issuer_key, ctx->md_alg, hash, 0, sig, &sig_len,
f_rng, p_rng ) ) != 0 )
{
return( ret );
}
/*
* Write data to output buffer
*/
c2 = buf + size;
MBEDTLS_ASN1_CHK_ADD( sig_and_oid_len, mbedtls_x509_write_sig( &c2, buf,
sig_oid, sig_oid_len, sig, sig_len ) );
if( len > (size_t)( c2 - buf ) )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
c2 -= len;
memcpy( c2, c, len );
len += sig_and_oid_len;
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c2, buf, len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c2, buf, MBEDTLS_ASN1_CONSTRUCTED |
MBEDTLS_ASN1_SEQUENCE ) );
return( (int) len );
}
