diff --git a/ChangeLog b/ChangeLog index 241b93d5e3e97d906df0a2ade40ef4e9e604064c..e9d4a1db970ac031d0d646647719654367e4253d 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,10 @@ 2014-08-18 Niels Möller + * testsuite/curve25519-dh-test.c (test_a): Use curve25519_mul. + (test_main): Use little-endian inputs for test_a. + (curve25519_sqrt, curve_25519): Deleted static helper functions, + no longer needed. + * curve25519-mul.c (curve25519_mul): New file and function. * curve25519.h (curve25519_mul): Declare it. * Makefile.in (hogweed_SOURCES): Added curve25519-mul.c. diff --git a/testsuite/curve25519-dh-test.c b/testsuite/curve25519-dh-test.c index 779736b6c609441fbb8bd274c834235b953b4404..cd075d9952f76fedb7d424f3aabff3ecd2cf980c 100644 --- a/testsuite/curve25519-dh-test.c +++ b/testsuite/curve25519-dh-test.c @@ -33,134 +33,6 @@ #include "curve25519.h" -static -int curve25519_sqrt (const struct ecc_curve *ecc, - mp_limb_t *rp, const mp_limb_t *ap) -{ - /* p-1 = 2^{255} - 20 = 4 (2^{253] - 5), s = 2^{253} - 5, e = 2 */ - - mpz_t g; - mpz_t sm1h; /* (s-1)/2 */ - mpz_t x; - mpz_t a; - mpz_t p; - mpz_t b; - mpz_t t; - int success; - - mpz_init_set_str (g, - "2b8324804fc1df0b2b4d00993dfbd7a7" - "2f431806ad2fe478c4ee1b274a0ea0b0", 16); - mpz_init_set_str (sm1h, - "fffffffffffffffffffffffffffffff" - "fffffffffffffffffffffffffffffffd", 16); - - mpz_init (x); - mpz_init (b); - mpz_init (t); - mpz_roinit_n (p, ecc->p, ecc->size); - mpz_roinit_n (a, ap, ecc->size); - - mpz_powm (x, a, sm1h, p); - mpz_mul (b, x, x); /* s-1 */ - mpz_mul (b, b, a); /* s */ - mpz_mod (b, b, p); - mpz_mul (x, x, a); /* (s+1)/2 */ - mpz_mod (x, x, p); - - if (mpz_cmp_ui (b, 1) != 0) - { - mpz_t t; - unsigned m, e; - mpz_init (t); - e = 2; - do - { - mpz_set (t, b); - m = 0; - do - { - m++; - if (m == e) - { - mpz_clear (t); - success = 0; - goto done; - } - mpz_mul (t, t, t); - mpz_mod (t, t, p); - } - while (mpz_cmp_ui (t, 1) != 0); - ASSERT (m < e); - mpz_set_ui (t, 1UL << (e - m - 1)); - mpz_powm (t, g, t, p); - mpz_mul (x, x, t); - mpz_mod (x, x, p); - mpz_mul (g, t, t); - mpz_mod (g, g, p); - mpz_mul (b, b, g); - mpz_mod (b, b, p); - e = m-1; - } - while (mpz_cmp_ui (b, 1) != 0); - - mpz_clear (t); - } - mpz_limbs_copy (rp, x, ecc->size); - success = 1; - done: - mpz_clear (g); - mpz_clear (sm1h); - mpz_clear (x); - mpz_clear (b); - mpz_clear (t); - return success; -} - -/* Computes the x coordinate of s G, where g is a scalar, and G is the - base point on the curve. If x is non-NULL, it gives the X - coordinate of the point G, otherwise, G is the specified - generator. */ -static void -curve_25519 (const struct ecc_curve *ecc, - mp_limb_t *r, const mp_limb_t *s, const mp_limb_t *x) -{ - mp_limb_t *p; - mp_limb_t *scratch; - mp_size_t itch; - - p = gmp_alloc_limbs (3*ecc->size); - - if (x) - { - itch = ECC_MUL_A_EH_ITCH (ecc->size); - scratch = gmp_alloc_limbs (itch); - mpn_copyi (p, x, ecc->size); - /* y^2 = x^3 + b x^2 + x = (x^2 + bx + 1) x = ((x+b)x + 1) x */ - ecc_modp_sqr (ecc, scratch, x); - ecc_modp_addmul_1 (ecc, scratch, x, 0x76d06ULL); - ecc_modp_add (ecc, scratch, scratch, ecc->unit); - ecc_modp_mul (ecc, scratch + ecc->size, scratch, x); - - if (!curve25519_sqrt (ecc, p + ecc->size, scratch + ecc->size)) - die ("Point not on curve.\n"); - mpn_copyi (p, x, ecc->size); - ecc_mul_a_eh (ecc, p, s, p, scratch); - } - else - { - itch = ECC_MUL_G_EH_ITCH (ecc->size); - scratch = gmp_alloc_limbs (itch); - ecc_mul_g_eh (ecc, p, s, scratch); - } - - ecc_eh_to_a (ecc, 2, r, p, scratch); - - /* FIXME: Convert to little-endian here? */ - gmp_free_limbs (p, 3*ecc->size); - gmp_free_limbs (scratch, itch); -} - static void test_g (const uint8_t *s, const uint8_t *r) { @@ -180,45 +52,32 @@ test_g (const uint8_t *s, const uint8_t *r) } static void -test_a (const char *bz, const char *sz, const char *pz) +test_a (const uint8_t *s, const uint8_t *b, const uint8_t *r) { - mpz_t B, S, R, X; - const struct ecc_curve *ecc = &nettle_curve25519; - - mpz_init (B); - mpz_init (S); - mpz_init (R); - mpz_init (X); - - mpz_set_str (B, bz, 16); - mpz_set_str (S, sz, 16); - mpz_set_str (R, pz, 16); - - ASSERT (mpz_size (S) == ecc->size); - ASSERT (mpz_size (B) == ecc->size); - - curve_25519 (ecc, mpz_limbs_write (X, ecc->size), - mpz_limbs_read (S), mpz_limbs_read (B)); - - mpz_limbs_finish (X, ecc->size); - if (mpz_cmp (X, R) != 0) + uint8_t p[CURVE25519_SIZE]; + if (!curve25519_mul (p, s, b)) { - fprintf (stderr, "curve25519 failure:\nB = "); - mpz_out_str (stderr, 16, B); - fprintf (stderr, "\nS = "); - mpz_out_str (stderr, 16, S); - fprintf (stderr, "\nX = "); - mpz_out_str (stderr, 16, X); - fprintf (stderr, " (bad)\nR = "); - mpz_out_str (stderr, 16, R); - fprintf (stderr, " (expected)\n"); + printf ("curve25519_mul returned 0:\ns = "); + print_hex (CURVE25519_SIZE, s); + printf ("\nb = "); + print_hex (CURVE25519_SIZE, b); + printf ("\n"); + abort (); + } + + if (!MEMEQ (CURVE25519_SIZE, p, r)) + { + printf ("curve25519_mul failure:\ns = "); + print_hex (CURVE25519_SIZE, s); + printf ("\nb = "); + print_hex (CURVE25519_SIZE, b); + printf ("\np = "); + print_hex (CURVE25519_SIZE, p); + printf (" (bad)\nr = "); + print_hex (CURVE25519_SIZE, r); + printf (" (expected)\n"); abort (); } - - mpz_clear (B); - mpz_clear (S); - mpz_clear (R); - mpz_clear (X); } void @@ -236,21 +95,17 @@ test_main (void) H("de9edb7d7b7dc1b4d35b61c2ece43537" "3f8343c85b78674dadfc7e146f882b4f")); - test_a ("4F2B886F147EFCAD4D67785BC843833F" - "3735E4ECC2615BD3B4C17D7B7DDB9EDE", - - "6A2CB91DA5FB77B12A99C0EB872F4CDF" - "4566B25172C1163C7DA518730A6D0770", - - "4217161E3C9BF076339ED147C9217EE0" - "250F3580F43B8E72E12DCEA45B9D5D4A"); - - test_a ("6A4E9BAA8EA9A4EBF41A38260D3ABF0D" - "5AF73EB4DC7D8B7454A7308909F02085", - - "6BE088FF278B2F1CFDB6182629B13B6F" - "E60E80838B7FE1794B8A4A627E08AB58", + test_a (H("77076d0a7318a57d3c16c17251b26645" + "df4c2f87ebc0992ab177fba51db92c2a"), + H("de9edb7d7b7dc1b4d35b61c2ece43537" + "3f8343c85b78674dadfc7e146f882b4f"), + H("4a5d9d5ba4ce2de1728e3bf480350f25" + "e07e21c947d19e3376f09b3c1e161742")); - "4217161E3C9BF076339ED147C9217EE0" - "250F3580F43B8E72E12DCEA45B9D5D4A"); + test_a (H("5dab087e624a8a4b79e17f8b83800ee6" + "6f3bb1292618b6fd1c2f8b27ff88e0eb"), + H("8520f0098930a754748b7ddcb43ef75a" + "0dbf3a0d26381af4eba4a98eaa9b4e6a"), + H("4a5d9d5ba4ce2de1728e3bf480350f25" + "e07e21c947d19e3376f09b3c1e161742")); }