[tls] Use iPXE native RSA algorithm

Signed-off-by: Michael Brown <mcb30@ipxe.org>
This commit is contained in:
Michael Brown
2012-03-18 14:44:53 +00:00
parent 7fb064470f
commit dc87161c30
4 changed files with 68 additions and 202 deletions

View File

@@ -33,161 +33,33 @@ FILE_LICENCE ( GPL2_OR_LATER );
* documented in RFC2313.
*/
/** Object Identifier for "rsaEncryption" (1.2.840.113549.1.1.1) */
static const uint8_t oid_rsa_encryption[] = { 0x2a, 0x86, 0x48, 0x86, 0xf7,
0x0d, 0x01, 0x01, 0x01 };
/**
* Identify X.509 certificate public key
* Identify X.509 certificate RSA public key
*
* @v certificate Certificate
* @v algorithm Public key algorithm to fill in
* @v pubkey Public key value to fill in
* @v rsa RSA public key to fill in
* @ret rc Return status code
*/
static int x509_public_key ( const struct asn1_cursor *certificate,
struct asn1_cursor *algorithm,
struct asn1_cursor *pubkey ) {
struct asn1_cursor cursor;
int x509_rsa_public_key ( const struct asn1_cursor *certificate,
struct x509_rsa_public_key *key ) {
struct asn1_cursor *cursor = &key->raw;
int rc;
/* Locate subjectPublicKeyInfo */
memcpy ( &cursor, certificate, sizeof ( cursor ) );
rc = ( asn1_enter ( &cursor, ASN1_SEQUENCE ), /* Certificate */
asn1_enter ( &cursor, ASN1_SEQUENCE ), /* tbsCertificate */
asn1_skip_if_exists ( &cursor, ASN1_EXPLICIT_TAG(0) ),/*version*/
asn1_skip ( &cursor, ASN1_INTEGER ), /* serialNumber */
asn1_skip ( &cursor, ASN1_SEQUENCE ), /* signature */
asn1_skip ( &cursor, ASN1_SEQUENCE ), /* issuer */
asn1_skip ( &cursor, ASN1_SEQUENCE ), /* validity */
asn1_skip ( &cursor, ASN1_SEQUENCE ), /* name */
asn1_enter ( &cursor, ASN1_SEQUENCE )/* subjectPublicKeyInfo*/);
memcpy ( cursor, certificate, sizeof ( *cursor ) );
rc = ( asn1_enter ( cursor, ASN1_SEQUENCE ), /* Certificate */
asn1_enter ( cursor, ASN1_SEQUENCE ), /* tbsCertificate */
asn1_skip_if_exists ( cursor, ASN1_EXPLICIT_TAG(0) ),/*version*/
asn1_skip ( cursor, ASN1_INTEGER ), /* serialNumber */
asn1_skip ( cursor, ASN1_SEQUENCE ), /* signature */
asn1_skip ( cursor, ASN1_SEQUENCE ), /* issuer */
asn1_skip ( cursor, ASN1_SEQUENCE ), /* validity */
asn1_skip ( cursor, ASN1_SEQUENCE ) /* name */ );
if ( rc != 0 ) {
DBG ( "Cannot locate subjectPublicKeyInfo in:\n" );
DBG_HDA ( 0, certificate->data, certificate->len );
return rc;
}
/* Locate algorithm */
memcpy ( algorithm, &cursor, sizeof ( *algorithm ) );
rc = ( asn1_enter ( algorithm, ASN1_SEQUENCE ) /* algorithm */ );
if ( rc != 0 ) {
DBG ( "Cannot locate algorithm in:\n" );
DBG_HDA ( 0, certificate->data, certificate->len );
return rc;
}
/* Locate subjectPublicKey */
memcpy ( pubkey, &cursor, sizeof ( *pubkey ) );
rc = ( asn1_skip ( pubkey, ASN1_SEQUENCE ), /* algorithm */
asn1_enter ( pubkey, ASN1_BIT_STRING ) /* subjectPublicKey*/ );
if ( rc != 0 ) {
DBG ( "Cannot locate subjectPublicKey in:\n" );
DBG_HDA ( 0, certificate->data, certificate->len );
return rc;
}
return 0;
}
/**
* Identify X.509 certificate RSA modulus and public exponent
*
* @v certificate Certificate
* @v rsa RSA public key to fill in
* @ret rc Return status code
*
* The caller is responsible for eventually calling
* x509_free_rsa_public_key() to free the storage allocated to hold
* the RSA modulus and exponent.
*/
int x509_rsa_public_key ( const struct asn1_cursor *certificate,
struct x509_rsa_public_key *rsa_pubkey ) {
struct asn1_cursor algorithm;
struct asn1_cursor pubkey;
struct asn1_cursor modulus;
struct asn1_cursor exponent;
int rc;
/* First, extract the public key algorithm and key data */
if ( ( rc = x509_public_key ( certificate, &algorithm,
&pubkey ) ) != 0 )
return rc;
/* Check that algorithm is RSA */
rc = ( asn1_enter ( &algorithm, ASN1_OID ) /* algorithm */ );
if ( rc != 0 ) {
DBG ( "Cannot locate algorithm:\n" );
DBG_HDA ( 0, certificate->data, certificate->len );
return rc;
}
if ( ( algorithm.len != sizeof ( oid_rsa_encryption ) ) ||
( memcmp ( algorithm.data, &oid_rsa_encryption,
sizeof ( oid_rsa_encryption ) ) != 0 ) ) {
DBG ( "algorithm is not rsaEncryption in:\n" );
DBG_HDA ( 0, certificate->data, certificate->len );
return -ENOTSUP;
}
/* Check that public key is a byte string, i.e. that the
* "unused bits" byte contains zero.
*/
if ( ( pubkey.len < 1 ) ||
( ( *( uint8_t * ) pubkey.data ) != 0 ) ) {
DBG ( "subjectPublicKey is not a byte string in:\n" );
DBG_HDA ( 0, certificate->data, certificate->len );
return -ENOTSUP;
}
pubkey.data++;
pubkey.len--;
/* Pick out the modulus and exponent */
rc = ( asn1_enter ( &pubkey, ASN1_SEQUENCE ) /* RSAPublicKey */ );
if ( rc != 0 ) {
DBG ( "Cannot locate RSAPublicKey in:\n" );
DBG_HDA ( 0, certificate->data, certificate->len );
return -ENOTSUP;
}
memcpy ( &modulus, &pubkey, sizeof ( modulus ) );
rc = ( asn1_enter ( &modulus, ASN1_INTEGER ) /* modulus */ );
if ( rc != 0 ) {
DBG ( "Cannot locate modulus in:\n" );
DBG_HDA ( 0, certificate->data, certificate->len );
return -ENOTSUP;
}
if ( modulus.len && ( ! *( ( uint8_t * ) modulus.data ) ) ) {
/* Skip positive sign byte */
modulus.data++;
modulus.len--;
}
memcpy ( &exponent, &pubkey, sizeof ( exponent ) );
rc = ( asn1_skip ( &exponent, ASN1_INTEGER ), /* modulus */
asn1_enter ( &exponent, ASN1_INTEGER ) /* publicExponent */ );
if ( rc != 0 ) {
DBG ( "Cannot locate publicExponent in:\n" );
DBG_HDA ( 0, certificate->data, certificate->len );
return -ENOTSUP;
}
if ( exponent.len && ( ! *( ( uint8_t * ) exponent.data ) ) ) {
/* Skip positive sign byte */
exponent.data++;
exponent.len--;
}
/* Allocate space and copy out modulus and exponent */
rsa_pubkey->modulus = malloc ( modulus.len + exponent.len );
if ( ! rsa_pubkey->modulus )
return -ENOMEM;
rsa_pubkey->exponent = ( rsa_pubkey->modulus + modulus.len );
memcpy ( rsa_pubkey->modulus, modulus.data, modulus.len );
rsa_pubkey->modulus_len = modulus.len;
memcpy ( rsa_pubkey->exponent, exponent.data, exponent.len );
rsa_pubkey->exponent_len = exponent.len;
DBG2 ( "RSA modulus:\n" );
DBG2_HDA ( 0, rsa_pubkey->modulus, rsa_pubkey->modulus_len );
DBG2 ( "RSA exponent:\n" );
DBG2_HDA ( 0, rsa_pubkey->exponent, rsa_pubkey->exponent_len );
return 0;
}