Beispiel #1
0
/*
 *  SubjectPublicKeyInfo  ::=  SEQUENCE  {
 *       algorithm            AlgorithmIdentifier,
 *       subjectPublicKey     BIT STRING }
 */
int pk_parse_subpubkey( unsigned char **p, const unsigned char *end,
                        pk_context *pk )
{
    int ret;
    size_t len;
    asn1_buf alg_params;
    pk_type_t pk_alg = POLARSSL_PK_NONE;
    const pk_info_t *pk_info;

    if( ( ret = asn1_get_tag( p, end, &len,
                    ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 )
    {
        return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret );
    }

    end = *p + len;

    if( ( ret = pk_get_pk_alg( p, end, &pk_alg, &alg_params ) ) != 0 )
        return( ret );

    if( ( ret = asn1_get_bitstring_null( p, end, &len ) ) != 0 )
        return( POLARSSL_ERR_PK_INVALID_PUBKEY + ret );

    if( *p + len != end )
        return( POLARSSL_ERR_PK_INVALID_PUBKEY +
                POLARSSL_ERR_ASN1_LENGTH_MISMATCH );

    if( ( pk_info = pk_info_from_type( pk_alg ) ) == NULL )
        return( POLARSSL_ERR_PK_UNKNOWN_PK_ALG );

    if( ( ret = pk_init_ctx( pk, pk_info ) ) != 0 )
        return( ret );

#if defined(POLARSSL_RSA_C)
    if( pk_alg == POLARSSL_PK_RSA )
    {
        ret = pk_get_shrsapubkey( p, end, pk_rsa( *pk ) );
    } else
#endif /* POLARSSL_RSA_C */
#if defined(POLARSSL_ECP_C)
    if( pk_alg == POLARSSL_PK_ECKEY_DH || pk_alg == POLARSSL_PK_ECKEY )
    {
        ret = pk_use_ecparams( &alg_params, &pk_ec( *pk )->grp );
        if( ret == 0 )
            ret = pk_get_ecpubkey( p, end, pk_ec( *pk ) );
    } else
#endif /* POLARSSL_ECP_C */
        ret = POLARSSL_ERR_PK_UNKNOWN_PK_ALG;

    if( ret == 0 && *p != end )
        ret = POLARSSL_ERR_PK_INVALID_PUBKEY
              POLARSSL_ERR_ASN1_LENGTH_MISMATCH;

    if( ret != 0 )
        pk_free( pk );

    return( ret );
}
Beispiel #2
0
int x509_get_sig( unsigned char **p, const unsigned char *end, x509_buf *sig )
{
    int ret;
    size_t len;

    if( ( end - *p ) < 1 )
        return( POLARSSL_ERR_X509_INVALID_SIGNATURE +
                POLARSSL_ERR_ASN1_OUT_OF_DATA );

    sig->tag = **p;

    if( ( ret = asn1_get_bitstring_null( p, end, &len ) ) != 0 )
        return( POLARSSL_ERR_X509_INVALID_SIGNATURE + ret );

    sig->len = len;
    sig->p = *p;

    *p += len;

    return( 0 );
}
Beispiel #3
0
/*
 * Parse a SEC1 encoded private EC key
 */
static int pk_parse_key_sec1_der( ecp_keypair *eck,
                                  const unsigned char *key,
                                  size_t keylen )
{
    int ret;
    int version, pubkey_done;
    size_t len;
    asn1_buf params;
    unsigned char *p = (unsigned char *) key;
    unsigned char *end = p + keylen;
    unsigned char *end2;

    /*
     * RFC 5915, or SEC1 Appendix C.4
     *
     * ECPrivateKey ::= SEQUENCE {
     *      version        INTEGER { ecPrivkeyVer1(1) } (ecPrivkeyVer1),
     *      privateKey     OCTET STRING,
     *      parameters [0] ECParameters {{ NamedCurve }} OPTIONAL,
     *      publicKey  [1] BIT STRING OPTIONAL
     *    }
     */
    if( ( ret = asn1_get_tag( &p, end, &len,
            ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 )
    {
        return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret );
    }

    end = p + len;

    if( ( ret = asn1_get_int( &p, end, &version ) ) != 0 )
        return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret );

    if( version != 1 )
        return( POLARSSL_ERR_PK_KEY_INVALID_VERSION );

    if( ( ret = asn1_get_tag( &p, end, &len, ASN1_OCTET_STRING ) ) != 0 )
        return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret );

    if( ( ret = shmpi_read_binary( &eck->d, p, len ) ) != 0 )
    {
        ecp_keypair_free( eck );
        return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret );
    }

    p += len;

    pubkey_done = 0;
    if( p != end )
    {
        /*
         * Is 'parameters' present?
         */
        if( ( ret = asn1_get_tag( &p, end, &len,
                        ASN1_CONTEXT_SPECIFIC | ASN1_CONSTRUCTED | 0 ) ) == 0 )
        {
            if( ( ret = pk_get_ecparams( &p, p + len, &params) ) != 0 ||
                ( ret = pk_use_ecparams( &params, &eck->grp )  ) != 0 )
            {
                ecp_keypair_free( eck );
                return( ret );
            }
        }
        else if( ret != POLARSSL_ERR_ASN1_UNEXPECTED_TAG )
        {
            ecp_keypair_free( eck );
            return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret );
        }

        /*
         * Is 'publickey' present? If not, or if we can't read it (eg because it
         * is compressed), create it from the private key.
         */
        if( ( ret = asn1_get_tag( &p, end, &len,
                        ASN1_CONTEXT_SPECIFIC | ASN1_CONSTRUCTED | 1 ) ) == 0 )
        {
            end2 = p + len;

            if( ( ret = asn1_get_bitstring_null( &p, end2, &len ) ) != 0 )
                return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret );

            if( p + len != end2 )
                return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT +
                        POLARSSL_ERR_ASN1_LENGTH_MISMATCH );

            if( ( ret = pk_get_ecpubkey( &p, end2, eck ) ) == 0 )
                pubkey_done = 1;
            else
            {
                /*
                 * The only acceptable failure mode of pk_get_ecpubkey() above
                 * is if the point format is not recognized.
                 */
                if( ret != POLARSSL_ERR_ECP_FEATURE_UNAVAILABLE )
                    return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT );
            }
        }
        else if( ret != POLARSSL_ERR_ASN1_UNEXPECTED_TAG )
        {
            ecp_keypair_free( eck );
            return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret );
        }
    }

    if( ! pubkey_done &&
        ( ret = ecp_mul( &eck->grp, &eck->Q, &eck->d, &eck->grp.G,
                                                      NULL, NULL ) ) != 0 )
    {
        ecp_keypair_free( eck );
        return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret );
    }

    if( ( ret = ecp_check_privkey( &eck->grp, &eck->d ) ) != 0 )
    {
        ecp_keypair_free( eck );
        return( ret );
    }

    return( 0 );
}