def sign(self, inputb):
"""
Sign the input with ECDSA method and returns the signature
"""
try:
size = len(inputb)
buff = OpenSSL.malloc(inputb, size)
digest = OpenSSL.malloc(0, 64)
md_ctx = OpenSSL.EVP_MD_CTX_create()
dgst_len = OpenSSL.pointer(OpenSSL.c_int(0))
siglen = OpenSSL.pointer(OpenSSL.c_int(0))
sig = OpenSSL.malloc(0, 151)
key = OpenSSL.EC_KEY_new_by_curve_name(self.curve)
if key == 0:
raise Exception("[OpenSSL] EC_KEY_new_by_curve_name FAIL ...")
priv_key = OpenSSL.BN_bin2bn(self.privkey, len(self.privkey), 0)
pub_key_x = OpenSSL.BN_bin2bn(self.pubkey_x, len(self.pubkey_x), 0)
pub_key_y = OpenSSL.BN_bin2bn(self.pubkey_y, len(self.pubkey_y), 0)
if (OpenSSL.EC_KEY_set_private_key(key, priv_key)) == 0:
raise Exception("[OpenSSL] EC_KEY_set_private_key FAIL ...")
group = OpenSSL.EC_KEY_get0_group(key)
pub_key = OpenSSL.EC_POINT_new(group)
if (OpenSSL.EC_POINT_set_affine_coordinates_GFp(group, pub_key,
pub_key_x,
pub_key_y,
0)) == 0:
raise Exception(
"[OpenSSL] EC_POINT_set_affine_coordinates_GFp FAIL ...")
if (OpenSSL.EC_KEY_set_public_key(key, pub_key)) == 0:
raise Exception("[OpenSSL] EC_KEY_set_public_key FAIL ...")
if (OpenSSL.EC_KEY_check_key(key)) == 0:
raise Exception("[OpenSSL] EC_KEY_check_key FAIL ...")
OpenSSL.EVP_MD_CTX_init(md_ctx)
OpenSSL.EVP_DigestInit(md_ctx, OpenSSL.EVP_ecdsa())
if (OpenSSL.EVP_DigestUpdate(md_ctx, buff, size)) == 0:
raise Exception("[OpenSSL] EVP_DigestUpdate FAIL ...")
OpenSSL.EVP_DigestFinal(md_ctx, digest, dgst_len)
OpenSSL.ECDSA_sign(0, digest, dgst_len.contents, sig, siglen, key)
if (OpenSSL.ECDSA_verify(0, digest, dgst_len.contents, sig,
siglen.contents, key)) != 1:
raise Exception("[OpenSSL] ECDSA_verify FAIL ...")
return sig.raw[:siglen.contents.value]
finally:
OpenSSL.EC_KEY_free(key)
OpenSSL.BN_free(pub_key_x)
OpenSSL.BN_free(pub_key_y)
OpenSSL.BN_free(priv_key)
OpenSSL.EC_POINT_free(pub_key)
OpenSSL.EVP_MD_CTX_destroy(md_ctx)
def verify(self, sig, inputb):
"""
Verify the signature with the input and the local public key.
Returns a boolean
"""
try:
bsig = OpenSSL.malloc(sig, len(sig))
binputb = OpenSSL.malloc(inputb, len(inputb))
digest = OpenSSL.malloc(0, 64)
dgst_len = OpenSSL.pointer(OpenSSL.c_int(0))
md_ctx = OpenSSL.EVP_MD_CTX_create()
key = OpenSSL.EC_KEY_new_by_curve_name(self.curve)
if key == 0:
raise Exception("[OpenSSL] EC_KEY_new_by_curve_name FAIL ...")
pub_key_x = OpenSSL.BN_bin2bn(self.pubkey_x, len(self.pubkey_x), 0)
pub_key_y = OpenSSL.BN_bin2bn(self.pubkey_y, len(self.pubkey_y), 0)
group = OpenSSL.EC_KEY_get0_group(key)
pub_key = OpenSSL.EC_POINT_new(group)
if (OpenSSL.EC_POINT_set_affine_coordinates_GFp(group, pub_key,
pub_key_x,
pub_key_y,
0)) == 0:
raise Exception(
"[OpenSSL] EC_POINT_set_affine_coordinates_GFp FAIL ...")
if (OpenSSL.EC_KEY_set_public_key(key, pub_key)) == 0:
raise Exception("[OpenSSL] EC_KEY_set_public_key FAIL ...")
if (OpenSSL.EC_KEY_check_key(key)) == 0:
raise Exception("[OpenSSL] EC_KEY_check_key FAIL ...")
OpenSSL.EVP_MD_CTX_init(md_ctx)
OpenSSL.EVP_DigestInit(md_ctx, OpenSSL.EVP_ecdsa())
if (OpenSSL.EVP_DigestUpdate(md_ctx, binputb, len(inputb))) == 0:
raise Exception("[OpenSSL] EVP_DigestUpdate FAIL ...")
OpenSSL.EVP_DigestFinal(md_ctx, digest, dgst_len)
ret = OpenSSL.ECDSA_verify(
0, digest, dgst_len.contents, bsig, len(sig), key)
if ret == -1:
return False # Fail to Check
else:
if ret == 0:
return False # Bad signature !
else:
return True # Good
return False
finally:
OpenSSL.EC_KEY_free(key)
OpenSSL.BN_free(pub_key_x)
OpenSSL.BN_free(pub_key_y)
OpenSSL.EC_POINT_free(pub_key)
OpenSSL.EVP_MD_CTX_destroy(md_ctx)
def raw_get_ecdh_key(self, pubkey_x, pubkey_y):
try:
ecdh_keybuffer = OpenSSL.malloc(0, 32)
other_key = OpenSSL.EC_KEY_new_by_curve_name(self.curve)
if other_key == 0:
raise Exception("[OpenSSL] EC_KEY_new_by_curve_name FAIL ...")
other_pub_key_x = OpenSSL.BN_bin2bn(pubkey_x, len(pubkey_x), 0)
other_pub_key_y = OpenSSL.BN_bin2bn(pubkey_y, len(pubkey_y), 0)
other_group = OpenSSL.EC_KEY_get0_group(other_key)
other_pub_key = OpenSSL.EC_POINT_new(other_group)
if (OpenSSL.EC_POINT_set_affine_coordinates_GFp(other_group,
other_pub_key,
other_pub_key_x,
other_pub_key_y,
0)) == 0:
raise Exception(
"[OpenSSL] EC_POINT_set_affine_coordinates_GFp FAIL ...")
if (OpenSSL.EC_KEY_set_public_key(other_key, other_pub_key)) == 0:
raise Exception("[OpenSSL] EC_KEY_set_public_key FAIL ...")
if (OpenSSL.EC_KEY_check_key(other_key)) == 0:
raise Exception("[OpenSSL] EC_KEY_check_key FAIL ...")
own_key = OpenSSL.EC_KEY_new_by_curve_name(self.curve)
if own_key == 0:
raise Exception("[OpenSSL] EC_KEY_new_by_curve_name FAIL ...")
own_priv_key = OpenSSL.BN_bin2bn(
self.privkey, len(self.privkey), 0)
if (OpenSSL.EC_KEY_set_private_key(own_key, own_priv_key)) == 0:
raise Exception("[OpenSSL] EC_KEY_set_private_key FAIL ...")
OpenSSL.ECDH_set_method(own_key, OpenSSL.ECDH_OpenSSL())
ecdh_keylen = OpenSSL.ECDH_compute_key(
ecdh_keybuffer, 32, other_pub_key, own_key, 0)
if ecdh_keylen != 32:
raise Exception("[OpenSSL] ECDH keylen FAIL ...")
return ecdh_keybuffer.raw
finally:
OpenSSL.EC_KEY_free(other_key)
OpenSSL.BN_free(other_pub_key_x)
OpenSSL.BN_free(other_pub_key_y)
OpenSSL.EC_POINT_free(other_pub_key)
OpenSSL.EC_KEY_free(own_key)
OpenSSL.BN_free(own_priv_key)
def raw_check_key(self, privkey, pubkey_x, pubkey_y, curve=None):
if curve is None:
curve = self.curve
elif type(curve) == str:
curve = OpenSSL.get_curve(curve)
else:
curve = curve
try:
key = OpenSSL.EC_KEY_new_by_curve_name(curve)
if key == 0:
raise Exception("[OpenSSL] EC_KEY_new_by_curve_name FAIL ...")
if privkey is not None:
priv_key = OpenSSL.BN_bin2bn(privkey, len(privkey), 0)
pub_key_x = OpenSSL.BN_bin2bn(pubkey_x, len(pubkey_x), 0)
pub_key_y = OpenSSL.BN_bin2bn(pubkey_y, len(pubkey_y), 0)
if privkey is not None:
if (OpenSSL.EC_KEY_set_private_key(key, priv_key)) == 0:
raise Exception(
"[OpenSSL] EC_KEY_set_private_key FAIL ...")
group = OpenSSL.EC_KEY_get0_group(key)
pub_key = OpenSSL.EC_POINT_new(group)
if (OpenSSL.EC_POINT_set_affine_coordinates_GFp(group, pub_key,
pub_key_x,
pub_key_y,
0)) == 0:
raise Exception(
"[OpenSSL] EC_POINT_set_affine_coordinates_GFp FAIL ...")
if (OpenSSL.EC_KEY_set_public_key(key, pub_key)) == 0:
raise Exception("[OpenSSL] EC_KEY_set_public_key FAIL ...")
if (OpenSSL.EC_KEY_check_key(key)) == 0:
raise Exception("[OpenSSL] EC_KEY_check_key FAIL ...")
return 0
finally:
OpenSSL.EC_KEY_free(key)
OpenSSL.BN_free(pub_key_x)
OpenSSL.BN_free(pub_key_y)
OpenSSL.EC_POINT_free(pub_key)
if privkey is not None:
OpenSSL.BN_free(priv_key)
def _generate(self):
try:
pub_key_x = OpenSSL.BN_new()
pub_key_y = OpenSSL.BN_new()
key = OpenSSL.EC_KEY_new_by_curve_name(self.curve)
if key == 0:
raise Exception("[OpenSSL] EC_KEY_new_by_curve_name FAIL ...")
if (OpenSSL.EC_KEY_generate_key(key)) == 0:
raise Exception("[OpenSSL] EC_KEY_generate_key FAIL ...")
if (OpenSSL.EC_KEY_check_key(key)) == 0:
raise Exception("[OpenSSL] EC_KEY_check_key FAIL ...")
priv_key = OpenSSL.EC_KEY_get0_private_key(key)
group = OpenSSL.EC_KEY_get0_group(key)
pub_key = OpenSSL.EC_KEY_get0_public_key(key)
if (OpenSSL.EC_POINT_get_affine_coordinates_GFp(group, pub_key,
pub_key_x,
pub_key_y, 0
)) == 0:
raise Exception(
"[OpenSSL] EC_POINT_get_affine_coordinates_GFp FAIL ...")
privkey = OpenSSL.malloc(0, OpenSSL.BN_num_bytes(priv_key))
pubkeyx = OpenSSL.malloc(0, OpenSSL.BN_num_bytes(pub_key_x))
pubkeyy = OpenSSL.malloc(0, OpenSSL.BN_num_bytes(pub_key_y))
OpenSSL.BN_bn2bin(priv_key, privkey)
privkey = privkey.raw
OpenSSL.BN_bn2bin(pub_key_x, pubkeyx)
pubkeyx = pubkeyx.raw
OpenSSL.BN_bn2bin(pub_key_y, pubkeyy)
pubkeyy = pubkeyy.raw
self.raw_check_key(privkey, pubkeyx, pubkeyy)
return privkey, pubkeyx, pubkeyy
finally:
OpenSSL.EC_KEY_free(key)
OpenSSL.BN_free(pub_key_x)
OpenSSL.BN_free(pub_key_y)