Commit ea8c77a5 authored by Bodo Möller's avatar Bodo Möller
Browse files

Fix ecdsatest.c. 

Submitted by: Emilia Kasper
parent a7c71d89

CHANGES

+6 −0
Original line number Diff line number Diff line
@@ -487,6 +487,9 @@ 


 Changes between 1.0.0e and 1.0.0f [xx XXX xxxx]



  *) Fix spurious failures in ecdsatest.c.

     [Emilia Käsper (Google)]



  *) Fix the BIO_f_buffer() implementation (which was mixing different

     interpretations of the '..._len' fields).

     [Adam Langley (Google)]
@@ -1411,6 +1414,9 @@ 
  

 Changes between 0.9.8r and 0.9.8s [xx XXX xxxx]



  *) Fix spurious failures in ecdsatest.c.

     [Emilia Käsper (Google)]



  *) Fix the BIO_f_buffer() implementation (which was mixing different

     interpretations of the '..._len' fields).

     [Adam Langley (Google)]

crypto/ecdsa/ecdsatest.c

+78 −7
Original line number Diff line number Diff line
@@ -295,9 +295,12 @@ int test_builtin(BIO *out) 
	size_t		crv_len = 0, n = 0;

	EC_KEY		*eckey = NULL, *wrong_eckey = NULL;

	EC_GROUP	*group;

	ECDSA_SIG	*ecdsa_sig = NULL;

	unsigned char	digest[20], wrong_digest[20];

	unsigned char	*signature = NULL;

	unsigned int	sig_len;

	unsigned char	*sig_ptr;

	unsigned char	*raw_buf = NULL;

	unsigned int	sig_len, degree, r_len, s_len, bn_len, buf_len;

	int		nid, ret =  0;

	

	/* fill digest values with some random data */
@@ -347,7 +350,8 @@ int test_builtin(BIO *out) 
		if (EC_KEY_set_group(eckey, group) == 0)

			goto builtin_err;

		EC_GROUP_free(group);

		if (EC_GROUP_get_degree(EC_KEY_get0_group(eckey)) < 160)

		degree = EC_GROUP_get_degree(EC_KEY_get0_group(eckey));

		if (degree < 160)

			/* drop the curve */ 

			{

			EC_KEY_free(eckey);
@@ -423,26 +427,89 @@ int test_builtin(BIO *out) 
			}

		BIO_printf(out, ".");

		(void)BIO_flush(out);

		/* modify a single byte of the signature */

		offset = signature[10] % sig_len;

		dirt   = signature[11];

		signature[offset] ^= dirt ? dirt : 1; 

		/* wrong length */

		if (ECDSA_verify(0, digest, 20, signature, sig_len - 1,

			eckey) == 1)

			{

			BIO_printf(out, " failed\n");

			goto builtin_err;

			}

		BIO_printf(out, ".");

		(void)BIO_flush(out);



		/* Modify a single byte of the signature: to ensure we don't

		 * garble the ASN1 structure, we read the raw signature and

		 * modify a byte in one of the bignums directly. */

		sig_ptr = signature;

		if ((ecdsa_sig = d2i_ECDSA_SIG(NULL, &sig_ptr, sig_len)) == NULL)

			{

			BIO_printf(out, " failed\n");

			goto builtin_err;

			}



		/* Store the two BIGNUMs in raw_buf. */

		r_len = BN_num_bytes(ecdsa_sig->r);

		s_len = BN_num_bytes(ecdsa_sig->s);

		bn_len = (degree + 7) / 8;

		if ((r_len > bn_len) || (s_len > bn_len))

			{

			BIO_printf(out, " failed\n");

			goto builtin_err;

			}

		buf_len = 2 * bn_len;

		if ((raw_buf = OPENSSL_malloc(buf_len)) == NULL)

			goto builtin_err;

		/* Pad the bignums with leading zeroes. */

		memset(raw_buf, 0, buf_len);

		BN_bn2bin(ecdsa_sig->r, raw_buf + bn_len - r_len);

		BN_bn2bin(ecdsa_sig->s, raw_buf + buf_len - s_len);



		/* Modify a single byte in the buffer. */

		offset = raw_buf[10] % buf_len;

		dirt   = raw_buf[11] ? raw_buf[11] : 1;

		raw_buf[offset] ^= dirt;

		/* Now read the BIGNUMs back in from raw_buf. */

		if ((BN_bin2bn(raw_buf, bn_len, ecdsa_sig->r) == NULL) ||

			(BN_bin2bn(raw_buf + bn_len, bn_len, ecdsa_sig->s) == NULL))

			goto builtin_err;



		sig_ptr = signature;

		sig_len = i2d_ECDSA_SIG(ecdsa_sig, &sig_ptr);

		if (ECDSA_verify(0, digest, 20, signature, sig_len, eckey) == 1)

			{

			BIO_printf(out, " failed\n");

			goto builtin_err;

			}

		/* Sanity check: undo the modification and verify signature. */

		raw_buf[offset] ^= dirt;

		if ((BN_bin2bn(raw_buf, bn_len, ecdsa_sig->r) == NULL) ||

			(BN_bin2bn(raw_buf + bn_len, bn_len, ecdsa_sig->s) == NULL))

			goto builtin_err;



		sig_ptr = signature;

		sig_len = i2d_ECDSA_SIG(ecdsa_sig, &sig_ptr);

		if (ECDSA_verify(0, digest, 20, signature, sig_len, eckey) != 1)

			{

			BIO_printf(out, " failed\n");

			goto builtin_err;

			}

		BIO_printf(out, ".");

		(void)BIO_flush(out);

		

		BIO_printf(out, " ok\n");

		/* cleanup */

		/* clean bogus errors */

		ERR_clear_error();

		OPENSSL_free(signature);

		signature = NULL;

		EC_KEY_free(eckey);

		eckey = NULL;

		EC_KEY_free(wrong_eckey);

		wrong_eckey = NULL;

		ECDSA_SIG_free(ecdsa_sig);

		ecdsa_sig = NULL;

		OPENSSL_free(raw_buf);

		raw_buf = NULL;

		}



	ret = 1;
@@ -451,8 +518,12 @@ builtin_err: 
		EC_KEY_free(eckey);

	if (wrong_eckey)

		EC_KEY_free(wrong_eckey);

	if (ecdsa_sig)

		ECDSA_SIG_free(ecdsa_sig);

	if (signature)

		OPENSSL_free(signature);

	if (raw_buf)

		OPENSSL_free(raw_buf);

	if (curves)

		OPENSSL_free(curves);