Date:   Fri, 5 Mar 2021 19:09:44 +0200
From:   Jarkko Sakkinen <jarkko@...nel.org>
To:     Stefan Berger <stefanb@...ux.vnet.ibm.com>
Cc:     keyrings@...r.kernel.org, linux-crypto@...r.kernel.org,
        davem@...emloft.net, herbert@...dor.apana.org.au,
        dhowells@...hat.com, zohar@...ux.ibm.com,
        linux-kernel@...r.kernel.org, patrick@...terwijk.org,
        linux-integrity@...r.kernel.org,
        Saulo Alessandre <saulo.alessandre@....jus.br>,
        Stefan Berger <stefanb@...ux.ibm.com>
Subject: Re: [PATCH v10 3/9] crypto: Add math to support fast NIST P384

On Thu, Mar 04, 2021 at 07:51:57PM -0500, Stefan Berger wrote:
> From: Saulo Alessandre <saulo.alessandre@....jus.br>
> 
> * crypto/ecc.c
>   - add vli_mmod_fast_384
>   - change some routines to pass ecc_curve forward until vli_mmod_fast
> 
> * crypto/ecc.h
>   - add ECC_CURVE_NIST_P384_DIGITS
>   - change ECC_MAX_DIGITS to P384 size
> 
> Signed-off-by: Saulo Alessandre <saulo.alessandre@....jus.br>
> Tested-by: Stefan Berger <stefanb@...ux.ibm.com>

Another "diffstat".

/Jarkko

> ---
>  crypto/ecc.c | 266 +++++++++++++++++++++++++++++++++++++--------------
>  crypto/ecc.h |   3 +-
>  2 files changed, 194 insertions(+), 75 deletions(-)
> 
> diff --git a/crypto/ecc.c b/crypto/ecc.c
> index f6cef5a7942d..c125576cda6b 100644
> --- a/crypto/ecc.c
> +++ b/crypto/ecc.c
> @@ -778,18 +778,133 @@ static void vli_mmod_fast_256(u64 *result, const u64 *product,
>  	}
>  }
>  
> +#define SL32OR32(x32, y32) (((u64)x32 << 32) | y32)
> +#define AND64H(x64)  (x64 & 0xffFFffFF00000000ull)
> +#define AND64L(x64)  (x64 & 0x00000000ffFFffFFull)
> +
> +/* Computes result = product % curve_prime
> + * from "Mathematical routines for the NIST prime elliptic curves"
> + */
> +static void vli_mmod_fast_384(u64 *result, const u64 *product,
> +				const u64 *curve_prime, u64 *tmp)
> +{
> +	int carry;
> +	const unsigned int ndigits = 6;
> +
> +	/* t */
> +	vli_set(result, product, ndigits);
> +
> +	/* s1 */
> +	tmp[0] = 0;		// 0 || 0
> +	tmp[1] = 0;		// 0 || 0
> +	tmp[2] = SL32OR32(product[11], (product[10]>>32));	//a22||a21
> +	tmp[3] = product[11]>>32;	// 0 ||a23
> +	tmp[4] = 0;		// 0 || 0
> +	tmp[5] = 0;		// 0 || 0
> +	carry = vli_lshift(tmp, tmp, 1, ndigits);
> +	carry += vli_add(result, result, tmp, ndigits);
> +
> +	/* s2 */
> +	tmp[0] = product[6];	//a13||a12
> +	tmp[1] = product[7];	//a15||a14
> +	tmp[2] = product[8];	//a17||a16
> +	tmp[3] = product[9];	//a19||a18
> +	tmp[4] = product[10];	//a21||a20
> +	tmp[5] = product[11];	//a23||a22
> +	carry += vli_add(result, result, tmp, ndigits);
> +
> +	/* s3 */
> +	tmp[0] = SL32OR32(product[11], (product[10]>>32));	//a22||a21
> +	tmp[1] = SL32OR32(product[6], (product[11]>>32));	//a12||a23
> +	tmp[2] = SL32OR32(product[7], (product[6])>>32);	//a14||a13
> +	tmp[3] = SL32OR32(product[8], (product[7]>>32));	//a16||a15
> +	tmp[4] = SL32OR32(product[9], (product[8]>>32));	//a18||a17
> +	tmp[5] = SL32OR32(product[10], (product[9]>>32));	//a20||a19
> +	carry += vli_add(result, result, tmp, ndigits);
> +
> +	/* s4 */
> +	tmp[0] = AND64H(product[11]);	//a23|| 0
> +	tmp[1] = (product[10]<<32);	//a20|| 0
> +	tmp[2] = product[6];	//a13||a12
> +	tmp[3] = product[7];	//a15||a14
> +	tmp[4] = product[8];	//a17||a16
> +	tmp[5] = product[9];	//a19||a18
> +	carry += vli_add(result, result, tmp, ndigits);
> +
> +	/* s5 */
> +	tmp[0] = 0;		//  0|| 0
> +	tmp[1] = 0;		//  0|| 0
> +	tmp[2] = product[10];	//a21||a20
> +	tmp[3] = product[11];	//a23||a22
> +	tmp[4] = 0;		//  0|| 0
> +	tmp[5] = 0;		//  0|| 0
> +	carry += vli_add(result, result, tmp, ndigits);
> +
> +	/* s6 */
> +	tmp[0] = AND64L(product[10]);	// 0 ||a20
> +	tmp[1] = AND64H(product[10]);	//a21|| 0
> +	tmp[2] = product[11];	//a23||a22
> +	tmp[3] = 0;		// 0 || 0
> +	tmp[4] = 0;		// 0 || 0
> +	tmp[5] = 0;		// 0 || 0
> +	carry += vli_add(result, result, tmp, ndigits);
> +
> +	/* d1 */
> +	tmp[0] = SL32OR32(product[6], (product[11]>>32));	//a12||a23
> +	tmp[1] = SL32OR32(product[7], (product[6]>>32));	//a14||a13
> +	tmp[2] = SL32OR32(product[8], (product[7]>>32));	//a16||a15
> +	tmp[3] = SL32OR32(product[9], (product[8]>>32));	//a18||a17
> +	tmp[4] = SL32OR32(product[10], (product[9]>>32));	//a20||a19
> +	tmp[5] = SL32OR32(product[11], (product[10]>>32));	//a22||a21
> +	carry -= vli_sub(result, result, tmp, ndigits);
> +
> +	/* d2 */
> +	tmp[0] = (product[10]<<32);	//a20|| 0
> +	tmp[1] = SL32OR32(product[11], (product[10]>>32));	//a22||a21
> +	tmp[2] = (product[11]>>32);	// 0 ||a23
> +	tmp[3] = 0;		// 0 || 0
> +	tmp[4] = 0;		// 0 || 0
> +	tmp[5] = 0;		// 0 || 0
> +	carry -= vli_sub(result, result, tmp, ndigits);
> +
> +	/* d3 */
> +	tmp[0] = 0;		// 0 || 0
> +	tmp[1] = AND64H(product[11]);	//a23|| 0
> +	tmp[2] = product[11]>>32;	// 0 ||a23
> +	tmp[3] = 0;		// 0 || 0
> +	tmp[4] = 0;		// 0 || 0
> +	tmp[5] = 0;		// 0 || 0
> +	carry -= vli_sub(result, result, tmp, ndigits);
> +
> +	if (carry < 0) {
> +		do {
> +			carry += vli_add(result, result, curve_prime, ndigits);
> +		} while (carry < 0);
> +	} else {
> +		while (carry || vli_cmp(curve_prime, result, ndigits) != 1)
> +			carry -= vli_sub(result, result, curve_prime, ndigits);
> +	}
> +
> +}
> +
> +#undef SL32OR32
> +#undef AND64H
> +#undef AND64L
> +
>  /* Computes result = product % curve_prime for different curve_primes.
>   *
>   * Note that curve_primes are distinguished just by heuristic check and
>   * not by complete conformance check.
>   */
>  static bool vli_mmod_fast(u64 *result, u64 *product,
> -			  const u64 *curve_prime, unsigned int ndigits)
> +			  const struct ecc_curve *curve)
>  {
>  	u64 tmp[2 * ECC_MAX_DIGITS];
> +	const u64 *curve_prime = curve->p;
> +	const unsigned int ndigits = curve->g.ndigits;
>  
> -	/* Currently, both NIST primes have -1 in lowest qword. */
> -	if (curve_prime[0] != -1ull) {
> +	/* Currently, all NIST have name nist_.* */
> +	if (strncmp(curve->name, "nist_", 5) != 0) {
>  		/* Try to handle Pseudo-Marsenne primes. */
>  		if (curve_prime[ndigits - 1] == -1ull) {
>  			vli_mmod_special(result, product, curve_prime,
> @@ -812,6 +927,9 @@ static bool vli_mmod_fast(u64 *result, u64 *product,
>  	case 4:
>  		vli_mmod_fast_256(result, product, curve_prime, tmp);
>  		break;
> +	case 6:
> +		vli_mmod_fast_384(result, product, curve_prime, tmp);
> +		break;
>  	default:
>  		pr_err_ratelimited("ecc: unsupported digits size!\n");
>  		return false;
> @@ -835,22 +953,22 @@ EXPORT_SYMBOL(vli_mod_mult_slow);
>  
>  /* Computes result = (left * right) % curve_prime. */
>  static void vli_mod_mult_fast(u64 *result, const u64 *left, const u64 *right,
> -			      const u64 *curve_prime, unsigned int ndigits)
> +			      const struct ecc_curve *curve)
>  {
>  	u64 product[2 * ECC_MAX_DIGITS];
>  
> -	vli_mult(product, left, right, ndigits);
> -	vli_mmod_fast(result, product, curve_prime, ndigits);
> +	vli_mult(product, left, right, curve->g.ndigits);
> +	vli_mmod_fast(result, product, curve);
>  }
>  
>  /* Computes result = left^2 % curve_prime. */
>  static void vli_mod_square_fast(u64 *result, const u64 *left,
> -				const u64 *curve_prime, unsigned int ndigits)
> +				const struct ecc_curve *curve)
>  {
>  	u64 product[2 * ECC_MAX_DIGITS];
>  
> -	vli_square(product, left, ndigits);
> -	vli_mmod_fast(result, product, curve_prime, ndigits);
> +	vli_square(product, left, curve->g.ndigits);
> +	vli_mmod_fast(result, product, curve);
>  }
>  
>  #define EVEN(vli) (!(vli[0] & 1))
> @@ -948,25 +1066,27 @@ static bool ecc_point_is_zero(const struct ecc_point *point)
>  
>  /* Double in place */
>  static void ecc_point_double_jacobian(u64 *x1, u64 *y1, u64 *z1,
> -				      u64 *curve_prime, unsigned int ndigits)
> +					const struct ecc_curve *curve)
>  {
>  	/* t1 = x, t2 = y, t3 = z */
>  	u64 t4[ECC_MAX_DIGITS];
>  	u64 t5[ECC_MAX_DIGITS];
> +	const u64 *curve_prime = curve->p;
> +	const unsigned int ndigits = curve->g.ndigits;
>  
>  	if (vli_is_zero(z1, ndigits))
>  		return;
>  
>  	/* t4 = y1^2 */
> -	vli_mod_square_fast(t4, y1, curve_prime, ndigits);
> +	vli_mod_square_fast(t4, y1, curve);
>  	/* t5 = x1*y1^2 = A */
> -	vli_mod_mult_fast(t5, x1, t4, curve_prime, ndigits);
> +	vli_mod_mult_fast(t5, x1, t4, curve);
>  	/* t4 = y1^4 */
> -	vli_mod_square_fast(t4, t4, curve_prime, ndigits);
> +	vli_mod_square_fast(t4, t4, curve);
>  	/* t2 = y1*z1 = z3 */
> -	vli_mod_mult_fast(y1, y1, z1, curve_prime, ndigits);
> +	vli_mod_mult_fast(y1, y1, z1, curve);
>  	/* t3 = z1^2 */
> -	vli_mod_square_fast(z1, z1, curve_prime, ndigits);
> +	vli_mod_square_fast(z1, z1, curve);
>  
>  	/* t1 = x1 + z1^2 */
>  	vli_mod_add(x1, x1, z1, curve_prime, ndigits);
> @@ -975,7 +1095,7 @@ static void ecc_point_double_jacobian(u64 *x1, u64 *y1, u64 *z1,
>  	/* t3 = x1 - z1^2 */
>  	vli_mod_sub(z1, x1, z1, curve_prime, ndigits);
>  	/* t1 = x1^2 - z1^4 */
> -	vli_mod_mult_fast(x1, x1, z1, curve_prime, ndigits);
> +	vli_mod_mult_fast(x1, x1, z1, curve);
>  
>  	/* t3 = 2*(x1^2 - z1^4) */
>  	vli_mod_add(z1, x1, x1, curve_prime, ndigits);
> @@ -992,7 +1112,7 @@ static void ecc_point_double_jacobian(u64 *x1, u64 *y1, u64 *z1,
>  	/* t1 = 3/2*(x1^2 - z1^4) = B */
>  
>  	/* t3 = B^2 */
> -	vli_mod_square_fast(z1, x1, curve_prime, ndigits);
> +	vli_mod_square_fast(z1, x1, curve);
>  	/* t3 = B^2 - A */
>  	vli_mod_sub(z1, z1, t5, curve_prime, ndigits);
>  	/* t3 = B^2 - 2A = x3 */
> @@ -1000,7 +1120,7 @@ static void ecc_point_double_jacobian(u64 *x1, u64 *y1, u64 *z1,
>  	/* t5 = A - x3 */
>  	vli_mod_sub(t5, t5, z1, curve_prime, ndigits);
>  	/* t1 = B * (A - x3) */
> -	vli_mod_mult_fast(x1, x1, t5, curve_prime, ndigits);
> +	vli_mod_mult_fast(x1, x1, t5, curve);
>  	/* t4 = B * (A - x3) - y1^4 = y3 */
>  	vli_mod_sub(t4, x1, t4, curve_prime, ndigits);
>  
> @@ -1010,23 +1130,22 @@ static void ecc_point_double_jacobian(u64 *x1, u64 *y1, u64 *z1,
>  }
>  
>  /* Modify (x1, y1) => (x1 * z^2, y1 * z^3) */
> -static void apply_z(u64 *x1, u64 *y1, u64 *z, u64 *curve_prime,
> -		    unsigned int ndigits)
> +static void apply_z(u64 *x1, u64 *y1, u64 *z, const struct ecc_curve *curve)
>  {
>  	u64 t1[ECC_MAX_DIGITS];
>  
> -	vli_mod_square_fast(t1, z, curve_prime, ndigits);    /* z^2 */
> -	vli_mod_mult_fast(x1, x1, t1, curve_prime, ndigits); /* x1 * z^2 */
> -	vli_mod_mult_fast(t1, t1, z, curve_prime, ndigits);  /* z^3 */
> -	vli_mod_mult_fast(y1, y1, t1, curve_prime, ndigits); /* y1 * z^3 */
> +	vli_mod_square_fast(t1, z, curve);		/* z^2 */
> +	vli_mod_mult_fast(x1, x1, t1, curve);	/* x1 * z^2 */
> +	vli_mod_mult_fast(t1, t1, z, curve);	/* z^3 */
> +	vli_mod_mult_fast(y1, y1, t1, curve);	/* y1 * z^3 */
>  }
>  
>  /* P = (x1, y1) => 2P, (x2, y2) => P' */
>  static void xycz_initial_double(u64 *x1, u64 *y1, u64 *x2, u64 *y2,
> -				u64 *p_initial_z, u64 *curve_prime,
> -				unsigned int ndigits)
> +				u64 *p_initial_z, const struct ecc_curve *curve)
>  {
>  	u64 z[ECC_MAX_DIGITS];
> +	const unsigned int ndigits = curve->g.ndigits;
>  
>  	vli_set(x2, x1, ndigits);
>  	vli_set(y2, y1, ndigits);
> @@ -1037,35 +1156,37 @@ static void xycz_initial_double(u64 *x1, u64 *y1, u64 *x2, u64 *y2,
>  	if (p_initial_z)
>  		vli_set(z, p_initial_z, ndigits);
>  
> -	apply_z(x1, y1, z, curve_prime, ndigits);
> +	apply_z(x1, y1, z, curve);
>  
> -	ecc_point_double_jacobian(x1, y1, z, curve_prime, ndigits);
> +	ecc_point_double_jacobian(x1, y1, z, curve);
>  
> -	apply_z(x2, y2, z, curve_prime, ndigits);
> +	apply_z(x2, y2, z, curve);
>  }
>  
>  /* Input P = (x1, y1, Z), Q = (x2, y2, Z)
>   * Output P' = (x1', y1', Z3), P + Q = (x3, y3, Z3)
>   * or P => P', Q => P + Q
>   */
> -static void xycz_add(u64 *x1, u64 *y1, u64 *x2, u64 *y2, u64 *curve_prime,
> -		     unsigned int ndigits)
> +static void xycz_add(u64 *x1, u64 *y1, u64 *x2, u64 *y2,
> +			const struct ecc_curve *curve)
>  {
>  	/* t1 = X1, t2 = Y1, t3 = X2, t4 = Y2 */
>  	u64 t5[ECC_MAX_DIGITS];
> +	const u64 *curve_prime = curve->p;
> +	const unsigned int ndigits = curve->g.ndigits;
>  
>  	/* t5 = x2 - x1 */
>  	vli_mod_sub(t5, x2, x1, curve_prime, ndigits);
>  	/* t5 = (x2 - x1)^2 = A */
> -	vli_mod_square_fast(t5, t5, curve_prime, ndigits);
> +	vli_mod_square_fast(t5, t5, curve);
>  	/* t1 = x1*A = B */
> -	vli_mod_mult_fast(x1, x1, t5, curve_prime, ndigits);
> +	vli_mod_mult_fast(x1, x1, t5, curve);
>  	/* t3 = x2*A = C */
> -	vli_mod_mult_fast(x2, x2, t5, curve_prime, ndigits);
> +	vli_mod_mult_fast(x2, x2, t5, curve);
>  	/* t4 = y2 - y1 */
>  	vli_mod_sub(y2, y2, y1, curve_prime, ndigits);
>  	/* t5 = (y2 - y1)^2 = D */
> -	vli_mod_square_fast(t5, y2, curve_prime, ndigits);
> +	vli_mod_square_fast(t5, y2, curve);
>  
>  	/* t5 = D - B */
>  	vli_mod_sub(t5, t5, x1, curve_prime, ndigits);
> @@ -1074,11 +1195,11 @@ static void xycz_add(u64 *x1, u64 *y1, u64 *x2, u64 *y2, u64 *curve_prime,
>  	/* t3 = C - B */
>  	vli_mod_sub(x2, x2, x1, curve_prime, ndigits);
>  	/* t2 = y1*(C - B) */
> -	vli_mod_mult_fast(y1, y1, x2, curve_prime, ndigits);
> +	vli_mod_mult_fast(y1, y1, x2, curve);
>  	/* t3 = B - x3 */
>  	vli_mod_sub(x2, x1, t5, curve_prime, ndigits);
>  	/* t4 = (y2 - y1)*(B - x3) */
> -	vli_mod_mult_fast(y2, y2, x2, curve_prime, ndigits);
> +	vli_mod_mult_fast(y2, y2, x2, curve);
>  	/* t4 = y3 */
>  	vli_mod_sub(y2, y2, y1, curve_prime, ndigits);
>  
> @@ -1089,22 +1210,24 @@ static void xycz_add(u64 *x1, u64 *y1, u64 *x2, u64 *y2, u64 *curve_prime,
>   * Output P + Q = (x3, y3, Z3), P - Q = (x3', y3', Z3)
>   * or P => P - Q, Q => P + Q
>   */
> -static void xycz_add_c(u64 *x1, u64 *y1, u64 *x2, u64 *y2, u64 *curve_prime,
> -		       unsigned int ndigits)
> +static void xycz_add_c(u64 *x1, u64 *y1, u64 *x2, u64 *y2,
> +			const struct ecc_curve *curve)
>  {
>  	/* t1 = X1, t2 = Y1, t3 = X2, t4 = Y2 */
>  	u64 t5[ECC_MAX_DIGITS];
>  	u64 t6[ECC_MAX_DIGITS];
>  	u64 t7[ECC_MAX_DIGITS];
> +	const u64 *curve_prime = curve->p;
> +	const unsigned int ndigits = curve->g.ndigits;
>  
>  	/* t5 = x2 - x1 */
>  	vli_mod_sub(t5, x2, x1, curve_prime, ndigits);
>  	/* t5 = (x2 - x1)^2 = A */
> -	vli_mod_square_fast(t5, t5, curve_prime, ndigits);
> +	vli_mod_square_fast(t5, t5, curve);
>  	/* t1 = x1*A = B */
> -	vli_mod_mult_fast(x1, x1, t5, curve_prime, ndigits);
> +	vli_mod_mult_fast(x1, x1, t5, curve);
>  	/* t3 = x2*A = C */
> -	vli_mod_mult_fast(x2, x2, t5, curve_prime, ndigits);
> +	vli_mod_mult_fast(x2, x2, t5, curve);
>  	/* t4 = y2 + y1 */
>  	vli_mod_add(t5, y2, y1, curve_prime, ndigits);
>  	/* t4 = y2 - y1 */
> @@ -1113,29 +1236,29 @@ static void xycz_add_c(u64 *x1, u64 *y1, u64 *x2, u64 *y2, u64 *curve_prime,
>  	/* t6 = C - B */
>  	vli_mod_sub(t6, x2, x1, curve_prime, ndigits);
>  	/* t2 = y1 * (C - B) */
> -	vli_mod_mult_fast(y1, y1, t6, curve_prime, ndigits);
> +	vli_mod_mult_fast(y1, y1, t6, curve);
>  	/* t6 = B + C */
>  	vli_mod_add(t6, x1, x2, curve_prime, ndigits);
>  	/* t3 = (y2 - y1)^2 */
> -	vli_mod_square_fast(x2, y2, curve_prime, ndigits);
> +	vli_mod_square_fast(x2, y2, curve);
>  	/* t3 = x3 */
>  	vli_mod_sub(x2, x2, t6, curve_prime, ndigits);
>  
>  	/* t7 = B - x3 */
>  	vli_mod_sub(t7, x1, x2, curve_prime, ndigits);
>  	/* t4 = (y2 - y1)*(B - x3) */
> -	vli_mod_mult_fast(y2, y2, t7, curve_prime, ndigits);
> +	vli_mod_mult_fast(y2, y2, t7, curve);
>  	/* t4 = y3 */
>  	vli_mod_sub(y2, y2, y1, curve_prime, ndigits);
>  
>  	/* t7 = (y2 + y1)^2 = F */
> -	vli_mod_square_fast(t7, t5, curve_prime, ndigits);
> +	vli_mod_square_fast(t7, t5, curve);
>  	/* t7 = x3' */
>  	vli_mod_sub(t7, t7, t6, curve_prime, ndigits);
>  	/* t6 = x3' - B */
>  	vli_mod_sub(t6, t7, x1, curve_prime, ndigits);
>  	/* t6 = (y2 + y1)*(x3' - B) */
> -	vli_mod_mult_fast(t6, t6, t5, curve_prime, ndigits);
> +	vli_mod_mult_fast(t6, t6, t5, curve);
>  	/* t2 = y3' */
>  	vli_mod_sub(y1, t6, y1, curve_prime, ndigits);
>  
> @@ -1165,41 +1288,37 @@ static void ecc_point_mult(struct ecc_point *result,
>  	vli_set(rx[1], point->x, ndigits);
>  	vli_set(ry[1], point->y, ndigits);
>  
> -	xycz_initial_double(rx[1], ry[1], rx[0], ry[0], initial_z, curve_prime,
> -			    ndigits);
> +	xycz_initial_double(rx[1], ry[1], rx[0], ry[0], initial_z, curve);
>  
>  	for (i = num_bits - 2; i > 0; i--) {
>  		nb = !vli_test_bit(scalar, i);
> -		xycz_add_c(rx[1 - nb], ry[1 - nb], rx[nb], ry[nb], curve_prime,
> -			   ndigits);
> -		xycz_add(rx[nb], ry[nb], rx[1 - nb], ry[1 - nb], curve_prime,
> -			 ndigits);
> +		xycz_add_c(rx[1 - nb], ry[1 - nb], rx[nb], ry[nb], curve);
> +		xycz_add(rx[nb], ry[nb], rx[1 - nb], ry[1 - nb], curve);
>  	}
>  
>  	nb = !vli_test_bit(scalar, 0);
> -	xycz_add_c(rx[1 - nb], ry[1 - nb], rx[nb], ry[nb], curve_prime,
> -		   ndigits);
> +	xycz_add_c(rx[1 - nb], ry[1 - nb], rx[nb], ry[nb], curve);
>  
>  	/* Find final 1/Z value. */
>  	/* X1 - X0 */
>  	vli_mod_sub(z, rx[1], rx[0], curve_prime, ndigits);
>  	/* Yb * (X1 - X0) */
> -	vli_mod_mult_fast(z, z, ry[1 - nb], curve_prime, ndigits);
> +	vli_mod_mult_fast(z, z, ry[1 - nb], curve);
>  	/* xP * Yb * (X1 - X0) */
> -	vli_mod_mult_fast(z, z, point->x, curve_prime, ndigits);
> +	vli_mod_mult_fast(z, z, point->x, curve);
>  
>  	/* 1 / (xP * Yb * (X1 - X0)) */
>  	vli_mod_inv(z, z, curve_prime, point->ndigits);
>  
>  	/* yP / (xP * Yb * (X1 - X0)) */
> -	vli_mod_mult_fast(z, z, point->y, curve_prime, ndigits);
> +	vli_mod_mult_fast(z, z, point->y, curve);
>  	/* Xb * yP / (xP * Yb * (X1 - X0)) */
> -	vli_mod_mult_fast(z, z, rx[1 - nb], curve_prime, ndigits);
> +	vli_mod_mult_fast(z, z, rx[1 - nb], curve);
>  	/* End 1/Z calculation */
>  
> -	xycz_add(rx[nb], ry[nb], rx[1 - nb], ry[1 - nb], curve_prime, ndigits);
> +	xycz_add(rx[nb], ry[nb], rx[1 - nb], ry[1 - nb], curve);
>  
> -	apply_z(rx[0], ry[0], z, curve_prime, ndigits);
> +	apply_z(rx[0], ry[0], z, curve);
>  
>  	vli_set(result->x, rx[0], ndigits);
>  	vli_set(result->y, ry[0], ndigits);
> @@ -1220,9 +1339,9 @@ static void ecc_point_add(const struct ecc_point *result,
>  	vli_mod_sub(z, result->x, p->x, curve->p, ndigits);
>  	vli_set(px, p->x, ndigits);
>  	vli_set(py, p->y, ndigits);
> -	xycz_add(px, py, result->x, result->y, curve->p, ndigits);
> +	xycz_add(px, py, result->x, result->y, curve);
>  	vli_mod_inv(z, z, curve->p, ndigits);
> -	apply_z(result->x, result->y, z, curve->p, ndigits);
> +	apply_z(result->x, result->y, z, curve);
>  }
>  
>  /* Computes R = u1P + u2Q mod p using Shamir's trick.
> @@ -1251,8 +1370,7 @@ void ecc_point_mult_shamir(const struct ecc_point *result,
>  	points[2] = q;
>  	points[3] = &sum;
>  
> -	num_bits = max(vli_num_bits(u1, ndigits),
> -		       vli_num_bits(u2, ndigits));
> +	num_bits = max(vli_num_bits(u1, ndigits), vli_num_bits(u2, ndigits));
>  	i = num_bits - 1;
>  	idx = (!!vli_test_bit(u1, i)) | ((!!vli_test_bit(u2, i)) << 1);
>  	point = points[idx];
> @@ -1263,7 +1381,7 @@ void ecc_point_mult_shamir(const struct ecc_point *result,
>  	z[0] = 1;
>  
>  	for (--i; i >= 0; i--) {
> -		ecc_point_double_jacobian(rx, ry, z, curve->p, ndigits);
> +		ecc_point_double_jacobian(rx, ry, z, curve);
>  		idx = (!!vli_test_bit(u1, i)) | ((!!vli_test_bit(u2, i)) << 1);
>  		point = points[idx];
>  		if (point) {
> @@ -1273,14 +1391,14 @@ void ecc_point_mult_shamir(const struct ecc_point *result,
>  
>  			vli_set(tx, point->x, ndigits);
>  			vli_set(ty, point->y, ndigits);
> -			apply_z(tx, ty, z, curve->p, ndigits);
> +			apply_z(tx, ty, z, curve);
>  			vli_mod_sub(tz, rx, tx, curve->p, ndigits);
> -			xycz_add(tx, ty, rx, ry, curve->p, ndigits);
> -			vli_mod_mult_fast(z, z, tz, curve->p, ndigits);
> +			xycz_add(tx, ty, rx, ry, curve);
> +			vli_mod_mult_fast(z, z, tz, curve);
>  		}
>  	}
>  	vli_mod_inv(z, z, curve->p, ndigits);
> -	apply_z(rx, ry, z, curve->p, ndigits);
> +	apply_z(rx, ry, z, curve);
>  }
>  EXPORT_SYMBOL(ecc_point_mult_shamir);
>  
> @@ -1434,10 +1552,10 @@ int ecc_is_pubkey_valid_partial(const struct ecc_curve *curve,
>  		return -EINVAL;
>  
>  	/* Check 3: Verify that y^2 == (x^3 + a·x + b) mod p */
> -	vli_mod_square_fast(yy, pk->y, curve->p, pk->ndigits); /* y^2 */
> -	vli_mod_square_fast(xxx, pk->x, curve->p, pk->ndigits); /* x^2 */
> -	vli_mod_mult_fast(xxx, xxx, pk->x, curve->p, pk->ndigits); /* x^3 */
> -	vli_mod_mult_fast(w, curve->a, pk->x, curve->p, pk->ndigits); /* a·x */
> +	vli_mod_square_fast(yy, pk->y, curve); /* y^2 */
> +	vli_mod_square_fast(xxx, pk->x, curve); /* x^2 */
> +	vli_mod_mult_fast(xxx, xxx, pk->x, curve); /* x^3 */
> +	vli_mod_mult_fast(w, curve->a, pk->x, curve); /* a·x */
>  	vli_mod_add(w, w, curve->b, curve->p, pk->ndigits); /* a·x + b */
>  	vli_mod_add(w, w, xxx, curve->p, pk->ndigits); /* x^3 + a·x + b */
>  	if (vli_cmp(yy, w, pk->ndigits) != 0) /* Equation */
> diff --git a/crypto/ecc.h b/crypto/ecc.h
> index 2ea86dfb5cf7..8f40ebd74565 100644
> --- a/crypto/ecc.h
> +++ b/crypto/ecc.h
> @@ -29,7 +29,8 @@
>  /* One digit is u64 qword. */
>  #define ECC_CURVE_NIST_P192_DIGITS  3
>  #define ECC_CURVE_NIST_P256_DIGITS  4
> -#define ECC_MAX_DIGITS             (512 / 64)
> +#define ECC_CURVE_NIST_P384_DIGITS  6
> +#define ECC_MAX_DIGITS              (512 / 64) /* due to ecrdsa */
>  
>  #define ECC_DIGITS_TO_BYTES_SHIFT 3
>  
> -- 
> 2.29.2
> 
> 

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