diff options
| -rw-r--r-- | networking/tls.h | 6 | ||||
| -rw-r--r-- | networking/tls_sp_c32.c | 184 |
2 files changed, 52 insertions, 138 deletions
diff --git a/networking/tls.h b/networking/tls.h index 154e9b2..215e92b 100644 --- a/networking/tls.h +++ b/networking/tls.h @@ -111,9 +111,9 @@ void xorbuf_aligned_AES_BLOCK_SIZE(void* buf, const void* mask) FAST_FUNC; #define CURVE25519_KEYSIZE 32 void curve_x25519_compute_pubkey_and_premaster( - uint8_t *pubkey, uint8_t *premaster, + uint8_t *pubkey32, uint8_t *premaster32, const uint8_t *peerkey32) FAST_FUNC; void curve_P256_compute_pubkey_and_premaster( - uint8_t *pubkey, uint8_t *premaster, - const uint8_t *peerkey32) FAST_FUNC; + uint8_t *pubkey2x32, uint8_t *premaster32, + const uint8_t *peerkey2x32) FAST_FUNC; diff --git a/networking/tls_sp_c32.c b/networking/tls_sp_c32.c index e7667de..b4e14de 100644 --- a/networking/tls_sp_c32.c +++ b/networking/tls_sp_c32.c @@ -57,7 +57,6 @@ typedef int32_t sp_digit; /* Implementation by Sean Parkinson. */ -/* Point structure to use. */ typedef struct sp_point { sp_digit x[2 * 10]; sp_digit y[2 * 10]; @@ -165,8 +164,6 @@ static void sp_256_point_from_bin2x32(sp_point* p, const uint8_t *bin2x32) /* Compare a with b in constant time. * - * a A single precision integer. - * b A single precision integer. * return -ve, 0 or +ve if a is less than, equal to or greater than b * respectively. */ @@ -181,8 +178,6 @@ static sp_digit sp_256_cmp_10(const sp_digit* a, const sp_digit* b) /* Compare two numbers to determine if they are equal. * - * a First number to compare. - * b Second number to compare. * return 1 when equal and 0 otherwise. */ static int sp_256_cmp_equal_10(const sp_digit* a, const sp_digit* b) @@ -198,10 +193,7 @@ static int sp_256_cmp_equal_10(const sp_digit* a, const sp_digit* b) #endif } -/* Normalize the values in each word to 26. - * - * a Array of sp_digit to normalize. - */ +/* Normalize the values in each word to 26 bits. */ static void sp_256_norm_10(sp_digit* a) { int i; @@ -211,12 +203,7 @@ static void sp_256_norm_10(sp_digit* a) } } -/* Add b to a into r. (r = a + b) - * - * r A single precision integer. - * a A single precision integer. - * b A single precision integer. - */ +/* Add b to a into r. (r = a + b) */ static void sp_256_add_10(sp_digit* r, const sp_digit* a, const sp_digit* b) { int i; @@ -226,11 +213,6 @@ static void sp_256_add_10(sp_digit* r, const sp_digit* a, const sp_digit* b) /* Conditionally add a and b using the mask m. * m is -1 to add and 0 when not. - * - * r A single precision number representing conditional add result. - * a A single precision number to add with. - * b A single precision number to add. - * m Mask value to apply. */ static void sp_256_cond_add_10(sp_digit* r, const sp_digit* a, const sp_digit* b, const sp_digit m) @@ -242,11 +224,6 @@ static void sp_256_cond_add_10(sp_digit* r, const sp_digit* a, /* Conditionally subtract b from a using the mask m. * m is -1 to subtract and 0 when not. - * - * r A single precision number representing condition subtract result. - * a A single precision number to subtract from. - * b A single precision number to subtract. - * m Mask value to apply. */ static void sp_256_cond_sub_10(sp_digit* r, const sp_digit* a, const sp_digit* b, const sp_digit m) @@ -256,23 +233,7 @@ static void sp_256_cond_sub_10(sp_digit* r, const sp_digit* a, r[i] = a[i] - (b[i] & m); } -/* Add 1 to a. (a = a + 1) - * - * r A single precision integer. - * a A single precision integer. - */ -static void sp_256_add_one_10(sp_digit* a) -{ - a[0]++; - sp_256_norm_10(a); -} - -/* Shift number left one bit. - * Bottom bit is lost. - * - * r Result of shift. - * a Number to shift. - */ +/* Shift number left one bit. Bottom bit is lost. */ static void sp_256_rshift1_10(sp_digit* r, sp_digit* a) { int i; @@ -381,14 +342,8 @@ static void sp_256_mod_mul_norm_10(sp_digit* r, const sp_digit* a) r[9] = (sp_digit)(t[7] >> 10); } -/* Mul a by scalar b and add into r. (r += a * b) - * - * r A single precision integer. - * a A single precision integer. - * b A scalar. - */ -static void sp_256_mul_add_10(sp_digit* r, const sp_digit* a, - const sp_digit b) +/* Mul a by scalar b and add into r. (r += a * b) */ +static void sp_256_mul_add_10(sp_digit* r, const sp_digit* a, sp_digit b) { int64_t tb = b; int64_t t = 0; @@ -402,12 +357,7 @@ static void sp_256_mul_add_10(sp_digit* r, const sp_digit* a, r[10] += t; } -/* Divide the number by 2 mod the modulus (prime). (r = a / 2 % m) - * - * r Result of division by 2. - * a Number to divide. - * m Modulus (prime). - */ +/* Divide the number by 2 mod the modulus (prime). (r = a / 2 % m) */ static void sp_256_div2_10(sp_digit* r, const sp_digit* a, const sp_digit* m) { sp_256_cond_add_10(r, a, m, 0 - (a[0] & 1)); @@ -415,11 +365,7 @@ static void sp_256_div2_10(sp_digit* r, const sp_digit* a, const sp_digit* m) sp_256_rshift1_10(r, r); } -/* Shift the result in the high 256 bits down to the bottom. - * - * r A single precision number. - * a A single precision number. - */ +/* Shift the result in the high 256 bits down to the bottom. */ static void sp_256_mont_shift_10(sp_digit* r, const sp_digit* a) { int i; @@ -438,13 +384,7 @@ static void sp_256_mont_shift_10(sp_digit* r, const sp_digit* a) memset(&r[10], 0, sizeof(*r) * 10); } -/* Add two Montgomery form numbers (r = a + b % m). - * - * r Result of addition. - * a First number to add in Montogmery form. - * b Second number to add in Montogmery form. - * m Modulus (prime). - */ +/* Add two Montgomery form numbers (r = a + b % m) */ static void sp_256_mont_add_10(sp_digit* r, const sp_digit* a, const sp_digit* b, const sp_digit* m) { @@ -454,12 +394,7 @@ static void sp_256_mont_add_10(sp_digit* r, const sp_digit* a, const sp_digit* b sp_256_norm_10(r); } -/* Double a Montgomery form number (r = a + a % m). - * - * r Result of doubling. - * a Number to double in Montogmery form. - * m Modulus (prime). - */ +/* Double a Montgomery form number (r = a + a % m) */ static void sp_256_mont_dbl_10(sp_digit* r, const sp_digit* a, const sp_digit* m) { sp_256_add_10(r, a, a); @@ -468,12 +403,7 @@ static void sp_256_mont_dbl_10(sp_digit* r, const sp_digit* a, const sp_digit* m sp_256_norm_10(r); } -/* Triple a Montgomery form number (r = a + a + a % m). - * - * r Result of Tripling. - * a Number to triple in Montogmery form. - * m Modulus (prime). - */ +/* Triple a Montgomery form number (r = a + a + a % m) */ static void sp_256_mont_tpl_10(sp_digit* r, const sp_digit* a, const sp_digit* m) { sp_256_add_10(r, a, a); @@ -486,27 +416,15 @@ static void sp_256_mont_tpl_10(sp_digit* r, const sp_digit* a, const sp_digit* m sp_256_norm_10(r); } -/* Sub b from a into r. (r = a - b) - * - * r A single precision integer. - * a A single precision integer. - * b A single precision integer. - */ -static void sp_256_sub_10(sp_digit* r, const sp_digit* a, - const sp_digit* b) +/* Sub b from a into r. (r = a - b) */ +static void sp_256_sub_10(sp_digit* r, const sp_digit* a, const sp_digit* b) { int i; for (i = 0; i < 10; i++) r[i] = a[i] - b[i]; } -/* Subtract two Montgomery form numbers (r = a - b % m). - * - * r Result of subtration. - * a Number to subtract from in Montogmery form. - * b Number to subtract with in Montogmery form. - * m Modulus (prime). - */ +/* Subtract two Montgomery form numbers (r = a - b % m) */ static void sp_256_mont_sub_10(sp_digit* r, const sp_digit* a, const sp_digit* b, const sp_digit* m) { @@ -554,12 +472,7 @@ static void sp_256_mont_reduce_10(sp_digit* a, const sp_digit* m, sp_digit mp) sp_256_norm_10(a); } -/* Multiply a and b into r. (r = a * b) - * - * r A single precision integer. - * a A single precision integer. - * b A single precision integer. - */ +/* Multiply a and b into r. (r = a * b) */ static void sp_256_mul_10(sp_digit* r, const sp_digit* a, const sp_digit* b) { int i, j, k; @@ -600,11 +513,7 @@ static void sp_256_mont_mul_10(sp_digit* r, const sp_digit* a, const sp_digit* b sp_256_mont_reduce_10(r, m, mp); } -/* Square a and put result in r. (r = a * a) - * - * r A single precision integer. - * a A single precision integer. - */ +/* Square a and put result in r. (r = a * a) */ static void sp_256_sqr_10(sp_digit* r, const sp_digit* a) { int i, j, k; @@ -937,8 +846,8 @@ static void sp_256_ecc_mulmod_10(sp_point* r, const sp_point* g, const sp_digit* else memcpy(r, t[0], sizeof(sp_point)); - memset(tmp, 0, sizeof(tmp)); - memset(td, 0, sizeof(td)); + memset(tmp, 0, sizeof(tmp)); //paranoia + memset(td, 0, sizeof(td)); //paranoia } /* Multiply the base point of P256 by the scalar and return the result. @@ -956,20 +865,20 @@ static void sp_256_ecc_mulmod_base_10(sp_point* r, sp_digit* k /*, int map*/) * The number is 0 padded to maximum size on output. * * priv Scalar to multiply the point by. - * peerkey2x32 Point to multiply. - * out Buffer to hold X ordinate. + * pub2x32 Point to multiply. + * out32 Buffer to hold X ordinate. */ -static void sp_ecc_secret_gen_256(sp_digit priv[10], const uint8_t *peerkey2x32, uint8_t* out32) +static void sp_ecc_secret_gen_256(sp_digit priv[10], const uint8_t *pub2x32, uint8_t* out32) { sp_point point[1]; #if FIXED_PEER_PUBKEY - memset((void*)peerkey32, 0x55, 64); + memset((void*)pub2x32, 0x55, 64); #endif - dump_hex("peerkey32 %s\n", peerkey2x32, 32); - dump_hex(" %s\n", peerkey2x32 + 32, 32); + dump_hex("peerkey %s\n", pub2x32, 32); /* in TLS, this is peer's public key */ + dump_hex(" %s\n", pub2x32 + 32, 32); - sp_256_point_from_bin2x32(point, peerkey2x32); + sp_256_point_from_bin2x32(point, pub2x32); dump_hex("point->x %s\n", point->x, sizeof(point->x)); dump_hex("point->y %s\n", point->y, sizeof(point->y)); @@ -979,14 +888,18 @@ static void sp_ecc_secret_gen_256(sp_digit priv[10], const uint8_t *peerkey2x32, dump_hex("out32: %s\n", out32, 32); } -/* Generates a scalar that is in the range 1..order-1. - * - * rng Random number generator. - * k Scalar value. - */ +/* Generates a scalar that is in the range 1..order-1. */ +#define SIMPLIFY 1 +/* Add 1 to a. (a = a + 1) */ +#if !SIMPLIFY +static void sp_256_add_one_10(sp_digit* a) +{ + a[0]++; + sp_256_norm_10(a); +} +#endif static void sp_256_ecc_gen_k_10(sp_digit k[10]) { -#define SIMPLIFY 1 #if !SIMPLIFY /* The order of the curve P256 minus 2. */ static const sp_digit p256_order2[10] = { @@ -1007,7 +920,7 @@ static void sp_256_ecc_gen_k_10(sp_digit k[10]) break; #else /* non-loopy version (and not needing p256_order2[]): - * if most-significant word seems that it can be larger + * if most-significant word seems that k can be larger * than p256_order2, fix it up: */ if (k[9] >= 0x03fffff) @@ -1015,21 +928,22 @@ static void sp_256_ecc_gen_k_10(sp_digit k[10]) break; #endif } +#if !SIMPLIFY sp_256_add_one_10(k); +#else + if (k[0] == 0) + k[0] = 1; +#endif #undef SIMPLIFY } -/* Makes a random EC key pair. - * - * priv Generated private value. - * pubkey Generated public point. - */ -static void sp_ecc_make_key_256(sp_digit k[10], uint8_t *pubkey) +/* Makes a random EC key pair. */ +static void sp_ecc_make_key_256(sp_digit privkey[10], uint8_t *pubkey) { sp_point point[1]; - sp_256_ecc_gen_k_10(k); - sp_256_ecc_mulmod_base_10(point, k); + sp_256_ecc_gen_k_10(privkey); + sp_256_ecc_mulmod_base_10(point, privkey); sp_256_to_bin(point->x, pubkey); sp_256_to_bin(point->y, pubkey + 32); @@ -1037,16 +951,16 @@ static void sp_ecc_make_key_256(sp_digit k[10], uint8_t *pubkey) } void FAST_FUNC curve_P256_compute_pubkey_and_premaster( - uint8_t *pubkey, uint8_t *premaster32, + uint8_t *pubkey2x32, uint8_t *premaster32, const uint8_t *peerkey2x32) { sp_digit privkey[10]; - sp_ecc_make_key_256(privkey, pubkey); - dump_hex("pubkey: %s\n", pubkey, 32); - dump_hex(" %s\n", pubkey + 32, 32); + sp_ecc_make_key_256(privkey, pubkey2x32); + dump_hex("pubkey: %s\n", pubkey2x32, 32); + dump_hex(" %s\n", pubkey2x32 + 32, 32); - /* Combine our privkey and peerkey32 to generate premaster */ + /* Combine our privkey and peer's public key to generate premaster */ sp_ecc_secret_gen_256(privkey, /*x,y:*/peerkey2x32, premaster32); dump_hex("premaster: %s\n", premaster32, 32); } |