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iwd
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ecdh: remove ECDH and unit tests 

ECDH was moved into ell and is no longer needed in IWD
This commit is contained in:
James Prestwood 2018-12-12 09:14:18 -08:00 committed by Denis Kenzior
parent e11c157478
commit c2094c5e04
3 changed files with 1 additions and 333 deletions
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9
Makefile.am
View File

@ -193,7 +193,6 @@ src_iwd_SOURCES = src/main.c linux/nl80211.h src/iwd.h \
src/adhoc.h src/adhoc.c \
src/sae.h src/sae.c \
src/nl80211util.h src/nl80211util.c \
src/ecdh.h src/ecdh.c \
src/owe.h src/owe.c \
$(eap_sources) \
$(builtin_sources)
@ -308,7 +307,7 @@ unit_tests = unit/test-cmac-aes \
unit/test-crypto unit/test-eapol unit/test-mpdu \
unit/test-ie unit/test-ssid-to-utf8 unit/test-ssid-security \
unit/test-arc4 unit/test-wsc unit/test-eap-mschapv2 \
unit/test-eap-sim unit/test-ecc unit/test-sae unit/test-ecdh
unit/test-eap-sim unit/test-ecc unit/test-sae
if CLIENT
unit_tests += unit/test-client
@ -443,12 +442,6 @@ unit_test_sae_SOURCES = unit/test-sae.c \
src/ecc.h src/ecc.c
unit_test_sae_LDADD = $(ell_ldadd)
unit_test_ecdh_SOURCES = unit/test-ecdh.c \
src/ecdh.h src/ecdh.c \
src/ecc.h src/ecc.c
unit_test_ecdh_LDADD = $(ell_ldadd)
unit_test_ecdh_LDFLAGS = -Wl,-wrap,l_getrandom
TESTS = $(unit_tests)
manual_pages = doc/iwmon.1

164
src/ecdh.c
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@ -1,164 +0,0 @@
/*
*
* Wireless daemon for Linux
*
* Copyright (C) 2018 Intel Corporation. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#include <ell/ell.h>
#include "ecdh.h"
#include "ecc.h"
static struct ecc_point p256_generator = CURVE_G_32;
static uint64_t p256_prime[4] = CURVE_P_32;
/*
* IETF - Compact representation of an elliptic curve point:
* https://tools.ietf.org/id/draft-jivsov-ecc-compact-00.xml
*
* "min(y,p-y) can be calculated with the help of the pre-calculated value
* p2=(p-1)/2. min(y,p-y) is y if y<p2 and p-y otherwise."
*/
static uint64_t p2[4] = { 0xffffffffffffffffull, 0x000000007fffffffull,
0x8000000000000000ull, 0x7fffffff80000000ull };
/*
* Some sane maximum for calculating the public key. This *shouldn't* ever be
* reached in normal conditions.
*/
#define ECDH_MAX_ITERATIONS 20
/*
* IETF draft-jivsov-ecc-compact-00 Section 4.2.1
*
* The following algorithm calculates a key pair {k, Q=k*G=(x,y)}, where k is
* the private key and Q=(x,y) is the public key.
*
* Black box generation:
* 1. Generate a key pair {k, Q=k*G=(x,y)} with KG
* 2. if( y != min(y,p-y) ) goto step 1
* 3. output {k, Q=(x,y)} as a key pair
*/
bool ecdh_generate_key_pair(void *private, size_t priv_len,
void *public, size_t pub_len)
{
struct ecc_point pub;
bool compliant = false;
int iter = 0;
if (pub_len > 64)
return false;
while (!compliant && iter++ < ECDH_MAX_ITERATIONS) {
if (!l_getrandom(private, priv_len))
return false;
/* private * G(x,y) = public key */
ecc_point_mult(&pub, &p256_generator,
(uint64_t *)private, NULL,
vli_num_bits((uint64_t *)private));
/* ensure public key is compliant */
if (vli_cmp(pub.y, p2) >= 0) {
compliant = true;
break;
}
}
if (!compliant) {
l_error("could not generate a compliant public key pair");
return false;
}
memcpy(public, &pub, pub_len);
return true;
}
/*
* IETF draft-jivsov-ecc-compact-00 Section 4.1
* Encoding and decoding of an elliptic curve point
* ...
* Decoding:
* Given the compact representation of Q, return canonical representation
* of Q=(x,y) as follows:
* 1. y' = sqrt( x^3 + a*x + b ), where y'>0
* 2. y = min(y',p-y')
* 3. Q=(x,y) is the canonical representation of the point
*/
static bool decode_point(const uint64_t *x, struct ecc_point *point)
{
uint64_t y_min[4];
if (!ecc_compute_y(y_min, (uint64_t *)x))
return false;
if (vli_cmp(y_min, p2) >= 0)
vli_mod_sub(point->y, p256_prime, y_min, p256_prime);
else
memcpy(point->y, y_min, 32);
memcpy(point->x, x, 32);
return true;
}
bool ecdh_generate_shared_secret(const void *private, const void *other_public,
size_t pub_len, void *secret,
size_t secret_len)
{
struct ecc_point product;
struct ecc_point public;
uint64_t z[4];
uint64_t x[4];
if (secret_len > 32)
return false;
/*
* TODO: Once other ECC groups are added this will need to be modified
* to check for 1/2 the full public key lengths
*/
if (pub_len == 32) {
/*
* Only half the public key was given, the remainder (Y) must
* be decoded.
*/
memcpy(x, other_public, 32);
if (!decode_point(x, &public)) {
l_error("could not decode compressed public key");
return false;
}
} else if (pub_len == 64) {
memcpy(&public, other_public, 64);
} else {
l_error("unsupported public key length %zu", pub_len);
return false;
}
if (!l_getrandom(z, sizeof(z)))
return false;
ecc_point_mult(&product, &public, (uint64_t *)private, z,
vli_num_bits(private));
memcpy(secret, product.x, secret_len);
return true;
}

161
unit/test-ecdh.c
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@ -1,161 +0,0 @@
/*
*
* Wireless daemon for Linux
*
* Copyright (C) 2018 Intel Corporation. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <string.h>
#include <assert.h>
#include <ell/ell.h>
#include "src/ecdh.h"
#include "src/ecc.h"
static bool use_real_getrandom = true;
bool __wrap_l_getrandom(void *buf, size_t len);
bool __real_l_getrandom(void *buf, size_t len);
bool __wrap_l_getrandom(void *buf, size_t len)
{
static const uint8_t random_buf[] = { 0x75, 0xc5, 0xfe, 0x3e, 0x53,
0xcc, 0x33, 0x33, 0x64, 0xea,
0xdd, 0xa1, 0xe6, 0x62, 0x7a,
0xb1, 0x98, 0xa7, 0xa0, 0x1e,
0xac, 0x4b, 0x1d, 0xb8, 0x71,
0x5b, 0x1d, 0x00, 0x36, 0xd0,
0x0f, 0xde };
if (use_real_getrandom)
return __real_l_getrandom(buf, len);
memcpy(buf, random_buf, len);
return true;
}
/*
* Tests the most basic case. Generate two full public keys and use to create
* two identical shared secrets.
*/
static void test_basic(const void *data)
{
uint8_t private1[32];
uint8_t private2[32];
uint8_t public1[64];
uint8_t public2[64];
uint8_t secret1[32];
uint8_t secret2[32];
assert(ecdh_generate_key_pair(private1, 32, public1, 64));
assert(ecdh_generate_key_pair(private2, 32, public2, 64));
assert(ecdh_generate_shared_secret(private1, public2, 64, secret1, 32));
assert(ecdh_generate_shared_secret(private2, public1, 64, secret2, 32));
assert(!memcmp(secret1, secret2, 32));
}
/*
* Tests public key compliance. When generating the public keys, only specify
* half their length (32). This requires ECDH to compute the remainder of the
* public key when generating the shared secret.
*/
static void test_compliant_key(const void *data)
{
uint8_t private1[32];
uint8_t private2[32];
uint8_t public1[32];
uint8_t public2[32];
uint8_t secret1[32];
uint8_t secret2[32];
assert(ecdh_generate_key_pair(private1, 32, public1, 32));
assert(ecdh_generate_key_pair(private2, 32, public2, 32));
assert(ecdh_generate_shared_secret(private1, public2, 32, secret1, 32));
assert(ecdh_generate_shared_secret(private2, public1, 32, secret2, 32));
assert(!memcmp(secret1, secret2, 32));
}
/*
* Test vector from RFC 5114 - 256-bit Random ECP Group
*/
static void test_vectors(const void *data)
{
uint64_t a_secret[4] = { 0x867B7291D507A3AFull, 0x3FAF432A5ABCE59Eull,
0xE96A8E337A128499ull, 0x814264145F2F56F2ull };
struct ecc_point a_public = {
.x = { 0x5E8D3B4BA83AEB15ull, 0x7165BE50BC42AE4Aull,
0xC9B5A8D4160D09E9ull, 0x2AF502F3BE8952F2ull },
.y = { 0xC0F5015ECE5EFD85ull, 0x6795BD4BFF6E6DE3ull,
0x8681A0F9872D79D5ull, 0xEB0FAF4CA986C4D3ull }
};
uint64_t b_secret[4] = { 0xEE1B593761CF7F41ull, 0x19CE6BCCAD562B8Eull,
0xDB95A200CC0AB26Aull, 0x2CE1788EC197E096ull };
struct ecc_point b_public = {
.x = { 0xB3AB0715F6CE51B0ull, 0xAE06AAEA279FA775ull,
0x5346E8DE6C2C8646ull, 0xB120DE4AA3649279ull },
.y = { 0x85C34DDE5708B2B6ull, 0x3727027092A84113ull,
0xD8EC685FA3F071D8ull, 0x9F1B7EECE20D7B5Eull }
};
uint64_t shared_secret[4] = { 0x7F80D21C820C2788ull,
0xF5811E9DC8EC8EEAull,
0x93310412D19A08F1ull,
0xDD0F5396219D1EA3ull };
uint64_t a_shared[4];
uint64_t b_shared[4];
use_real_getrandom = false;
assert(ecdh_generate_shared_secret(a_secret, (const void *)&b_public,
64, a_shared, 32));
assert(ecdh_generate_shared_secret(b_secret, (const void *)&a_public,
64, b_shared, 32));
assert(!memcmp(a_shared, shared_secret, 32));
assert(!memcmp(b_shared, shared_secret, 32));
use_real_getrandom = true;
}
int main(int argc, char *argv[])
{
l_test_init(&argc, &argv);
if (l_getrandom_is_supported()) {
l_test_add("ECDH Basic", test_basic, NULL);
l_test_add("ECDH Compliant key", test_compliant_key, NULL);
}
l_test_add("ECDH test vector", test_vectors, NULL);
return l_test_run();
}