mirror of
https://github.com/openssl/openssl.git
synced 2024-12-09 05:51:54 +08:00
Remove some unneeded stuff
Reviewed-by: Bernd Edlinger <bernd.edlinger@hotmail.de> (Merged from https://github.com/openssl/openssl/pull/5105)
This commit is contained in:
parent
6853d09368
commit
67f1cccd7e
@ -42,9 +42,7 @@
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#define EDDSA_USE_SIGMA_ISOGENY 0
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static const int EDWARDS_D = -39081;
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static const scalar_t point_scalarmul_adjustment = {{{
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SC_LIMB(0xc873d6d54a7bb0cf), SC_LIMB(0xe933d8d723a70aad), SC_LIMB(0xbb124b65129c96fd), SC_LIMB(0x00000008335dc163)
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}}}, precomputed_scalarmul_adjustment = {{{
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static const scalar_t precomputed_scalarmul_adjustment = {{{
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SC_LIMB(0xc873d6d54a7bb0cf), SC_LIMB(0xe933d8d723a70aad), SC_LIMB(0xbb124b65129c96fd), SC_LIMB(0x00000008335dc163)
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}}};
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@ -95,8 +93,6 @@ const gf RISTRETTO_FACTOR = {{{
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#define WBITS DECAF_WORD_BITS /* NB this may be different from ARCH_WORD_BITS */
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extern const point_t API_NS(point_base);
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/* Projective Niels coordinates */
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typedef struct { gf a, b, c; } niels_s, niels_t[1];
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typedef struct { niels_t n; gf z; } VECTOR_ALIGNED pniels_s, pniels_t[1];
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@ -108,9 +104,6 @@ extern const gf API_NS(precomputed_base_as_fe)[];
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const precomputed_s *API_NS(precomputed_base) =
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(const precomputed_s *) &API_NS(precomputed_base_as_fe);
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const size_t API_NS(sizeof_precomputed_s) = sizeof(precomputed_s);
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const size_t API_NS(alignof_precomputed_s) = sizeof(big_register_t);
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/** Inverse. */
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static void
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gf_invert(gf y, const gf x, int assert_nonzero) {
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@ -127,228 +120,6 @@ gf_invert(gf y, const gf x, int assert_nonzero) {
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/** identity = (0,1) */
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const point_t API_NS(point_identity) = {{{{{0}}},{{{1}}},{{{1}}},{{{0}}}}};
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/* Predeclare because not static: called by elligator */
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void API_NS(deisogenize) (
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gf_s *__restrict__ s,
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gf_s *__restrict__ inv_el_sum,
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gf_s *__restrict__ inv_el_m1,
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const point_t p,
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mask_t toggle_s,
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mask_t toggle_altx,
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mask_t toggle_rotation
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);
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void API_NS(deisogenize) (
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gf_s *__restrict__ s,
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gf_s *__restrict__ inv_el_sum,
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gf_s *__restrict__ inv_el_m1,
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const point_t p,
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mask_t toggle_s,
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mask_t toggle_altx,
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mask_t toggle_rotation
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) {
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#if COFACTOR == 4 && !IMAGINE_TWIST
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(void)toggle_rotation; /* Only applies to cofactor 8 */
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gf t1;
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gf_s *t2 = s, *t3=inv_el_sum, *t4=inv_el_m1;
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gf_add(t1,p->x,p->t);
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gf_sub(t2,p->x,p->t);
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gf_mul(t3,t1,t2); /* t3 = num */
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gf_sqr(t2,p->x);
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gf_mul(t1,t2,t3);
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gf_mulw(t2,t1,-1-TWISTED_D); /* -x^2 * (a-d) * num */
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gf_isr(t1,t2); /* t1 = isr */
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gf_mul(t2,t1,t3); /* t2 = ratio */
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gf_mul(t4,t2,RISTRETTO_FACTOR);
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mask_t negx = gf_lobit(t4) ^ toggle_altx;
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gf_cond_neg(t2, negx);
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gf_mul(t3,t2,p->z);
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gf_sub(t3,t3,p->t);
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gf_mul(t2,t3,p->x);
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gf_mulw(t4,t2,-1-TWISTED_D);
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gf_mul(s,t4,t1);
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mask_t lobs = gf_lobit(s);
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gf_cond_neg(s,lobs);
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gf_copy(inv_el_m1,p->x);
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gf_cond_neg(inv_el_m1,~lobs^negx^toggle_s);
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gf_add(inv_el_m1,inv_el_m1,p->t);
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#elif COFACTOR == 8 && IMAGINE_TWIST
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/* More complicated because of rotation */
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gf t1,t2,t3,t4,t5;
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gf_add(t1,p->z,p->y);
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gf_sub(t2,p->z,p->y);
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gf_mul(t3,t1,t2); /* t3 = num */
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gf_mul(t2,p->x,p->y); /* t2 = den */
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gf_sqr(t1,t2);
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gf_mul(t4,t1,t3);
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gf_mulw(t1,t4,-1-TWISTED_D);
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gf_isr(t4,t1); /* isqrt(num*(a-d)*den^2) */
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gf_mul(t1,t2,t4);
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gf_mul(t2,t1,RISTRETTO_FACTOR); /* t2 = "iden" in ristretto.sage */
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gf_mul(t1,t3,t4); /* t1 = "inum" in ristretto.sage */
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/* Calculate altxy = iden*inum*i*t^2*(d-a) */
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gf_mul(t3,t1,t2);
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gf_mul_i(t4,t3);
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gf_mul(t3,t4,p->t);
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gf_mul(t4,t3,p->t);
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gf_mulw(t3,t4,TWISTED_D+1); /* iden*inum*i*t^2*(d-1) */
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mask_t rotate = toggle_rotation ^ gf_lobit(t3);
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/* Rotate if altxy is negative */
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gf_cond_swap(t1,t2,rotate);
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gf_mul_i(t4,p->x);
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gf_cond_sel(t4,p->y,t4,rotate); /* t4 = "fac" = ix if rotate, else y */
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gf_mul_i(t5,RISTRETTO_FACTOR); /* t5 = imi */
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gf_mul(t3,t5,t2); /* iden * imi */
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gf_mul(t2,t5,t1);
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gf_mul(t5,t2,p->t); /* "altx" = iden*imi*t */
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mask_t negx = gf_lobit(t5) ^ toggle_altx;
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gf_cond_neg(t1,negx^rotate);
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gf_mul(t2,t1,p->z);
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gf_add(t2,t2,ONE);
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gf_mul(inv_el_sum,t2,t4);
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gf_mul(s,inv_el_sum,t3);
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mask_t negs = gf_lobit(s);
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gf_cond_neg(s,negs);
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mask_t negz = ~negs ^ toggle_s ^ negx;
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gf_copy(inv_el_m1,p->z);
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gf_cond_neg(inv_el_m1,negz);
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gf_sub(inv_el_m1,inv_el_m1,t4);
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#else
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#error "Cofactor must be 4 (with no IMAGINE_TWIST) or 8 (with IMAGINE_TWIST)"
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#endif
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}
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void API_NS(point_encode)( unsigned char ser[SER_BYTES], const point_t p ) {
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gf s,ie1,ie2;
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API_NS(deisogenize)(s,ie1,ie2,p,0,0,0);
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gf_serialize(ser,s,1);
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}
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decaf_error_t API_NS(point_decode) (
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point_t p,
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const unsigned char ser[SER_BYTES],
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decaf_bool_t allow_identity
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) {
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gf s, s2, num, tmp;
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gf_s *tmp2=s2, *ynum=p->z, *isr=p->x, *den=p->t;
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mask_t succ = gf_deserialize(s, ser, 1, 0);
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succ &= bool_to_mask(allow_identity) | ~gf_eq(s, ZERO);
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succ &= ~gf_lobit(s);
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gf_sqr(s2,s); /* s^2 = -as^2 */
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#if IMAGINE_TWIST
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gf_sub(s2,ZERO,s2); /* -as^2 */
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#endif
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gf_sub(den,ONE,s2); /* 1+as^2 */
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gf_add(ynum,ONE,s2); /* 1-as^2 */
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gf_mulw(num,s2,-4*TWISTED_D);
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gf_sqr(tmp,den); /* tmp = den^2 */
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gf_add(num,tmp,num); /* num = den^2 - 4*d*s^2 */
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gf_mul(tmp2,num,tmp); /* tmp2 = num*den^2 */
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succ &= gf_isr(isr,tmp2); /* isr = 1/sqrt(num*den^2) */
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gf_mul(tmp,isr,den); /* isr*den */
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gf_mul(p->y,tmp,ynum); /* isr*den*(1-as^2) */
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gf_mul(tmp2,tmp,s); /* s*isr*den */
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gf_add(tmp2,tmp2,tmp2); /* 2*s*isr*den */
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gf_mul(tmp,tmp2,isr); /* 2*s*isr^2*den */
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gf_mul(p->x,tmp,num); /* 2*s*isr^2*den*num */
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gf_mul(tmp,tmp2,RISTRETTO_FACTOR); /* 2*s*isr*den*magic */
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gf_cond_neg(p->x,gf_lobit(tmp)); /* flip x */
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#if COFACTOR==8
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/* Additionally check y != 0 and x*y*isomagic nonegative */
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succ &= ~gf_eq(p->y,ZERO);
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gf_mul(tmp,p->x,p->y);
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gf_mul(tmp2,tmp,RISTRETTO_FACTOR);
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succ &= ~gf_lobit(tmp2);
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#endif
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#if IMAGINE_TWIST
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gf_copy(tmp,p->x);
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gf_mul_i(p->x,tmp);
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#endif
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/* Fill in z and t */
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gf_copy(p->z,ONE);
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gf_mul(p->t,p->x,p->y);
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assert(API_NS(point_valid)(p) | ~succ);
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return decaf_succeed_if(mask_to_bool(succ));
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}
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void API_NS(point_sub) (
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point_t p,
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const point_t q,
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const point_t r
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) {
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gf a, b, c, d;
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gf_sub_nr ( b, q->y, q->x ); /* 3+e */
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gf_sub_nr ( d, r->y, r->x ); /* 3+e */
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gf_add_nr ( c, r->y, r->x ); /* 2+e */
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gf_mul ( a, c, b );
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gf_add_nr ( b, q->y, q->x ); /* 2+e */
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gf_mul ( p->y, d, b );
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gf_mul ( b, r->t, q->t );
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gf_mulw ( p->x, b, 2*EFF_D );
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gf_add_nr ( b, a, p->y ); /* 2+e */
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gf_sub_nr ( c, p->y, a ); /* 3+e */
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gf_mul ( a, q->z, r->z );
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gf_add_nr ( a, a, a ); /* 2+e */
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if (GF_HEADROOM <= 3) gf_weak_reduce(a); /* or 1+e */
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#if NEG_D
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gf_sub_nr ( p->y, a, p->x ); /* 4+e or 3+e */
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gf_add_nr ( a, a, p->x ); /* 3+e or 2+e */
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#else
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gf_add_nr ( p->y, a, p->x ); /* 3+e or 2+e */
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gf_sub_nr ( a, a, p->x ); /* 4+e or 3+e */
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#endif
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gf_mul ( p->z, a, p->y );
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gf_mul ( p->x, p->y, c );
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gf_mul ( p->y, a, b );
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gf_mul ( p->t, b, c );
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}
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void API_NS(point_add) (
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point_t p,
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const point_t q,
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const point_t r
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) {
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gf a, b, c, d;
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gf_sub_nr ( b, q->y, q->x ); /* 3+e */
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gf_sub_nr ( c, r->y, r->x ); /* 3+e */
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gf_add_nr ( d, r->y, r->x ); /* 2+e */
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gf_mul ( a, c, b );
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gf_add_nr ( b, q->y, q->x ); /* 2+e */
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gf_mul ( p->y, d, b );
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gf_mul ( b, r->t, q->t );
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gf_mulw ( p->x, b, 2*EFF_D );
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gf_add_nr ( b, a, p->y ); /* 2+e */
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gf_sub_nr ( c, p->y, a ); /* 3+e */
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gf_mul ( a, q->z, r->z );
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gf_add_nr ( a, a, a ); /* 2+e */
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if (GF_HEADROOM <= 3) gf_weak_reduce(a); /* or 1+e */
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#if NEG_D
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gf_add_nr ( p->y, a, p->x ); /* 3+e or 2+e */
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gf_sub_nr ( a, a, p->x ); /* 4+e or 3+e */
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#else
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gf_sub_nr ( p->y, a, p->x ); /* 4+e or 3+e */
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gf_add_nr ( a, a, p->x ); /* 3+e or 2+e */
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#endif
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gf_mul ( p->z, a, p->y );
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gf_mul ( p->x, p->y, c );
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gf_mul ( p->y, a, b );
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gf_mul ( p->t, b, c );
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}
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static DECAF_NOINLINE void
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point_double_internal (
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point_t p,
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@ -377,16 +148,6 @@ void API_NS(point_double)(point_t p, const point_t q) {
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point_double_internal(p,q,0);
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}
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void API_NS(point_negate) (
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point_t nega,
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const point_t a
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) {
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gf_sub(nega->x, ZERO, a->x);
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gf_copy(nega->y, a->y);
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gf_copy(nega->z, a->z);
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gf_sub(nega->t, ZERO, a->t);
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}
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/* Operations on [p]niels */
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static DECAF_INLINE void
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cond_neg_niels (
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@ -499,265 +260,6 @@ sub_pniels_from_pt (
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sub_niels_from_pt( p, pn->n, before_double );
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}
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static DECAF_NOINLINE void
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prepare_fixed_window(
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pniels_t *multiples,
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const point_t b,
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int ntable
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) {
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point_t tmp;
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pniels_t pn;
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int i;
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point_double_internal(tmp, b, 0);
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pt_to_pniels(pn, tmp);
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pt_to_pniels(multiples[0], b);
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API_NS(point_copy)(tmp, b);
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for (i=1; i<ntable; i++) {
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add_pniels_to_pt(tmp, pn, 0);
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pt_to_pniels(multiples[i], tmp);
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}
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OPENSSL_cleanse(pn,sizeof(pn));
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OPENSSL_cleanse(tmp,sizeof(tmp));
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}
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void API_NS(point_scalarmul) (
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point_t a,
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const point_t b,
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const scalar_t scalar
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) {
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const int WINDOW = DECAF_WINDOW_BITS,
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WINDOW_MASK = (1<<WINDOW)-1,
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WINDOW_T_MASK = WINDOW_MASK >> 1,
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NTABLE = 1<<(WINDOW-1);
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scalar_t scalar1x;
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API_NS(scalar_add)(scalar1x, scalar, point_scalarmul_adjustment);
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API_NS(scalar_halve)(scalar1x,scalar1x);
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/* Set up a precomputed table with odd multiples of b. */
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pniels_t pn, multiples[NTABLE];
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point_t tmp;
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prepare_fixed_window(multiples, b, NTABLE);
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/* Initialize. */
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int i,j,first=1;
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i = SCALAR_BITS - ((SCALAR_BITS-1) % WINDOW) - 1;
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for (; i>=0; i-=WINDOW) {
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/* Fetch another block of bits */
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word_t bits = scalar1x->limb[i/WBITS] >> (i%WBITS);
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if (i%WBITS >= WBITS-WINDOW && i/WBITS<SCALAR_LIMBS-1) {
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bits ^= scalar1x->limb[i/WBITS+1] << (WBITS - (i%WBITS));
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}
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bits &= WINDOW_MASK;
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mask_t inv = (bits>>(WINDOW-1))-1;
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bits ^= inv;
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/* Add in from table. Compute t only on last iteration. */
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constant_time_lookup(pn, multiples, sizeof(pn), NTABLE, bits & WINDOW_T_MASK);
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cond_neg_niels(pn->n, inv);
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if (first) {
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pniels_to_pt(tmp, pn);
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first = 0;
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} else {
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/* Using Hisil et al's lookahead method instead of extensible here
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* for no particular reason. Double WINDOW times, but only compute t on
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* the last one.
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*/
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for (j=0; j<WINDOW-1; j++)
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point_double_internal(tmp, tmp, -1);
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point_double_internal(tmp, tmp, 0);
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add_pniels_to_pt(tmp, pn, i ? -1 : 0);
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}
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}
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/* Write out the answer */
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API_NS(point_copy)(a,tmp);
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OPENSSL_cleanse(scalar1x,sizeof(scalar1x));
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OPENSSL_cleanse(pn,sizeof(pn));
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OPENSSL_cleanse(multiples,sizeof(multiples));
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OPENSSL_cleanse(tmp,sizeof(tmp));
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}
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void API_NS(point_double_scalarmul) (
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point_t a,
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const point_t b,
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const scalar_t scalarb,
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const point_t c,
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const scalar_t scalarc
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) {
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const int WINDOW = DECAF_WINDOW_BITS,
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WINDOW_MASK = (1<<WINDOW)-1,
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WINDOW_T_MASK = WINDOW_MASK >> 1,
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NTABLE = 1<<(WINDOW-1);
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scalar_t scalar1x, scalar2x;
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API_NS(scalar_add)(scalar1x, scalarb, point_scalarmul_adjustment);
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API_NS(scalar_halve)(scalar1x,scalar1x);
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API_NS(scalar_add)(scalar2x, scalarc, point_scalarmul_adjustment);
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API_NS(scalar_halve)(scalar2x,scalar2x);
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|
||||
/* Set up a precomputed table with odd multiples of b. */
|
||||
pniels_t pn, multiples1[NTABLE], multiples2[NTABLE];
|
||||
point_t tmp;
|
||||
prepare_fixed_window(multiples1, b, NTABLE);
|
||||
prepare_fixed_window(multiples2, c, NTABLE);
|
||||
|
||||
/* Initialize. */
|
||||
int i,j,first=1;
|
||||
i = SCALAR_BITS - ((SCALAR_BITS-1) % WINDOW) - 1;
|
||||
|
||||
for (; i>=0; i-=WINDOW) {
|
||||
/* Fetch another block of bits */
|
||||
word_t bits1 = scalar1x->limb[i/WBITS] >> (i%WBITS),
|
||||
bits2 = scalar2x->limb[i/WBITS] >> (i%WBITS);
|
||||
if (i%WBITS >= WBITS-WINDOW && i/WBITS<SCALAR_LIMBS-1) {
|
||||
bits1 ^= scalar1x->limb[i/WBITS+1] << (WBITS - (i%WBITS));
|
||||
bits2 ^= scalar2x->limb[i/WBITS+1] << (WBITS - (i%WBITS));
|
||||
}
|
||||
bits1 &= WINDOW_MASK;
|
||||
bits2 &= WINDOW_MASK;
|
||||
mask_t inv1 = (bits1>>(WINDOW-1))-1;
|
||||
mask_t inv2 = (bits2>>(WINDOW-1))-1;
|
||||
bits1 ^= inv1;
|
||||
bits2 ^= inv2;
|
||||
|
||||
/* Add in from table. Compute t only on last iteration. */
|
||||
constant_time_lookup(pn, multiples1, sizeof(pn), NTABLE, bits1 & WINDOW_T_MASK);
|
||||
cond_neg_niels(pn->n, inv1);
|
||||
if (first) {
|
||||
pniels_to_pt(tmp, pn);
|
||||
first = 0;
|
||||
} else {
|
||||
/* Using Hisil et al's lookahead method instead of extensible here
|
||||
* for no particular reason. Double WINDOW times, but only compute t on
|
||||
* the last one.
|
||||
*/
|
||||
for (j=0; j<WINDOW-1; j++)
|
||||
point_double_internal(tmp, tmp, -1);
|
||||
point_double_internal(tmp, tmp, 0);
|
||||
add_pniels_to_pt(tmp, pn, 0);
|
||||
}
|
||||
constant_time_lookup(pn, multiples2, sizeof(pn), NTABLE, bits2 & WINDOW_T_MASK);
|
||||
cond_neg_niels(pn->n, inv2);
|
||||
add_pniels_to_pt(tmp, pn, i?-1:0);
|
||||
}
|
||||
|
||||
/* Write out the answer */
|
||||
API_NS(point_copy)(a,tmp);
|
||||
|
||||
|
||||
OPENSSL_cleanse(scalar1x,sizeof(scalar1x));
|
||||
OPENSSL_cleanse(scalar2x,sizeof(scalar2x));
|
||||
OPENSSL_cleanse(pn,sizeof(pn));
|
||||
OPENSSL_cleanse(multiples1,sizeof(multiples1));
|
||||
OPENSSL_cleanse(multiples2,sizeof(multiples2));
|
||||
OPENSSL_cleanse(tmp,sizeof(tmp));
|
||||
}
|
||||
|
||||
void API_NS(point_dual_scalarmul) (
|
||||
point_t a1,
|
||||
point_t a2,
|
||||
const point_t b,
|
||||
const scalar_t scalar1,
|
||||
const scalar_t scalar2
|
||||
) {
|
||||
const int WINDOW = DECAF_WINDOW_BITS,
|
||||
WINDOW_MASK = (1<<WINDOW)-1,
|
||||
WINDOW_T_MASK = WINDOW_MASK >> 1,
|
||||
NTABLE = 1<<(WINDOW-1);
|
||||
|
||||
scalar_t scalar1x, scalar2x;
|
||||
API_NS(scalar_add)(scalar1x, scalar1, point_scalarmul_adjustment);
|
||||
API_NS(scalar_halve)(scalar1x,scalar1x);
|
||||
API_NS(scalar_add)(scalar2x, scalar2, point_scalarmul_adjustment);
|
||||
API_NS(scalar_halve)(scalar2x,scalar2x);
|
||||
|
||||
/* Set up a precomputed table with odd multiples of b. */
|
||||
point_t multiples1[NTABLE], multiples2[NTABLE], working, tmp;
|
||||
pniels_t pn;
|
||||
|
||||
API_NS(point_copy)(working, b);
|
||||
|
||||
/* Initialize. */
|
||||
int i,j;
|
||||
|
||||
for (i=0; i<NTABLE; i++) {
|
||||
API_NS(point_copy)(multiples1[i], API_NS(point_identity));
|
||||
API_NS(point_copy)(multiples2[i], API_NS(point_identity));
|
||||
}
|
||||
|
||||
for (i=0; i<SCALAR_BITS; i+=WINDOW) {
|
||||
if (i) {
|
||||
for (j=0; j<WINDOW-1; j++)
|
||||
point_double_internal(working, working, -1);
|
||||
point_double_internal(working, working, 0);
|
||||
}
|
||||
|
||||
/* Fetch another block of bits */
|
||||
word_t bits1 = scalar1x->limb[i/WBITS] >> (i%WBITS),
|
||||
bits2 = scalar2x->limb[i/WBITS] >> (i%WBITS);
|
||||
if (i%WBITS >= WBITS-WINDOW && i/WBITS<SCALAR_LIMBS-1) {
|
||||
bits1 ^= scalar1x->limb[i/WBITS+1] << (WBITS - (i%WBITS));
|
||||
bits2 ^= scalar2x->limb[i/WBITS+1] << (WBITS - (i%WBITS));
|
||||
}
|
||||
bits1 &= WINDOW_MASK;
|
||||
bits2 &= WINDOW_MASK;
|
||||
mask_t inv1 = (bits1>>(WINDOW-1))-1;
|
||||
mask_t inv2 = (bits2>>(WINDOW-1))-1;
|
||||
bits1 ^= inv1;
|
||||
bits2 ^= inv2;
|
||||
|
||||
pt_to_pniels(pn, working);
|
||||
|
||||
constant_time_lookup(tmp, multiples1, sizeof(tmp), NTABLE, bits1 & WINDOW_T_MASK);
|
||||
cond_neg_niels(pn->n, inv1);
|
||||
/* add_pniels_to_pt(multiples1[bits1 & WINDOW_T_MASK], pn, 0); */
|
||||
add_pniels_to_pt(tmp, pn, 0);
|
||||
constant_time_insert(multiples1, tmp, sizeof(tmp), NTABLE, bits1 & WINDOW_T_MASK);
|
||||
|
||||
|
||||
constant_time_lookup(tmp, multiples2, sizeof(tmp), NTABLE, bits2 & WINDOW_T_MASK);
|
||||
cond_neg_niels(pn->n, inv1^inv2);
|
||||
/* add_pniels_to_pt(multiples2[bits2 & WINDOW_T_MASK], pn, 0); */
|
||||
add_pniels_to_pt(tmp, pn, 0);
|
||||
constant_time_insert(multiples2, tmp, sizeof(tmp), NTABLE, bits2 & WINDOW_T_MASK);
|
||||
}
|
||||
|
||||
if (NTABLE > 1) {
|
||||
API_NS(point_copy)(working, multiples1[NTABLE-1]);
|
||||
API_NS(point_copy)(tmp , multiples2[NTABLE-1]);
|
||||
|
||||
for (i=NTABLE-1; i>1; i--) {
|
||||
API_NS(point_add)(multiples1[i-1], multiples1[i-1], multiples1[i]);
|
||||
API_NS(point_add)(multiples2[i-1], multiples2[i-1], multiples2[i]);
|
||||
API_NS(point_add)(working, working, multiples1[i-1]);
|
||||
API_NS(point_add)(tmp, tmp, multiples2[i-1]);
|
||||
}
|
||||
|
||||
API_NS(point_add)(multiples1[0], multiples1[0], multiples1[1]);
|
||||
API_NS(point_add)(multiples2[0], multiples2[0], multiples2[1]);
|
||||
point_double_internal(working, working, 0);
|
||||
point_double_internal(tmp, tmp, 0);
|
||||
API_NS(point_add)(a1, working, multiples1[0]);
|
||||
API_NS(point_add)(a2, tmp, multiples2[0]);
|
||||
} else {
|
||||
API_NS(point_copy)(a1, multiples1[0]);
|
||||
API_NS(point_copy)(a2, multiples2[0]);
|
||||
}
|
||||
|
||||
OPENSSL_cleanse(scalar1x,sizeof(scalar1x));
|
||||
OPENSSL_cleanse(scalar2x,sizeof(scalar2x));
|
||||
OPENSSL_cleanse(pn,sizeof(pn));
|
||||
OPENSSL_cleanse(multiples1,sizeof(multiples1));
|
||||
OPENSSL_cleanse(multiples2,sizeof(multiples2));
|
||||
OPENSSL_cleanse(tmp,sizeof(tmp));
|
||||
OPENSSL_cleanse(working,sizeof(working));
|
||||
}
|
||||
|
||||
decaf_bool_t API_NS(point_eq) ( const point_t p, const point_t q ) {
|
||||
/* equality mod 2-torsion compares x/y */
|
||||
gf a, b;
|
||||
@ -803,161 +305,6 @@ decaf_bool_t API_NS(point_valid) (
|
||||
return mask_to_bool(out);
|
||||
}
|
||||
|
||||
void API_NS(point_debugging_torque) (
|
||||
point_t q,
|
||||
const point_t p
|
||||
) {
|
||||
#if COFACTOR == 8 && IMAGINE_TWIST
|
||||
gf tmp;
|
||||
gf_mul(tmp,p->x,SQRT_MINUS_ONE);
|
||||
gf_mul(q->x,p->y,SQRT_MINUS_ONE);
|
||||
gf_copy(q->y,tmp);
|
||||
gf_copy(q->z,p->z);
|
||||
gf_sub(q->t,ZERO,p->t);
|
||||
#else
|
||||
gf_sub(q->x,ZERO,p->x);
|
||||
gf_sub(q->y,ZERO,p->y);
|
||||
gf_copy(q->z,p->z);
|
||||
gf_copy(q->t,p->t);
|
||||
#endif
|
||||
}
|
||||
|
||||
void API_NS(point_debugging_pscale) (
|
||||
point_t q,
|
||||
const point_t p,
|
||||
const uint8_t factor[SER_BYTES]
|
||||
) {
|
||||
gf gfac,tmp;
|
||||
/* NB this means you'll never pscale by negative numbers for p521 */
|
||||
ignore_result(gf_deserialize(gfac,factor,0,0));
|
||||
gf_cond_sel(gfac,gfac,ONE,gf_eq(gfac,ZERO));
|
||||
gf_mul(tmp,p->x,gfac);
|
||||
gf_copy(q->x,tmp);
|
||||
gf_mul(tmp,p->y,gfac);
|
||||
gf_copy(q->y,tmp);
|
||||
gf_mul(tmp,p->z,gfac);
|
||||
gf_copy(q->z,tmp);
|
||||
gf_mul(tmp,p->t,gfac);
|
||||
gf_copy(q->t,tmp);
|
||||
}
|
||||
|
||||
static void gf_batch_invert (
|
||||
gf *__restrict__ out,
|
||||
const gf *in,
|
||||
unsigned int n
|
||||
) {
|
||||
gf t1;
|
||||
assert(n>1);
|
||||
|
||||
gf_copy(out[1], in[0]);
|
||||
int i;
|
||||
for (i=1; i<(int) (n-1); i++) {
|
||||
gf_mul(out[i+1], out[i], in[i]);
|
||||
}
|
||||
gf_mul(out[0], out[n-1], in[n-1]);
|
||||
|
||||
gf_invert(out[0], out[0], 1);
|
||||
|
||||
for (i=n-1; i>0; i--) {
|
||||
gf_mul(t1, out[i], out[0]);
|
||||
gf_copy(out[i], t1);
|
||||
gf_mul(t1, out[0], in[i]);
|
||||
gf_copy(out[0], t1);
|
||||
}
|
||||
}
|
||||
|
||||
static void batch_normalize_niels (
|
||||
niels_t *table,
|
||||
const gf *zs,
|
||||
gf *__restrict__ zis,
|
||||
int n
|
||||
) {
|
||||
int i;
|
||||
gf product;
|
||||
gf_batch_invert(zis, zs, n);
|
||||
|
||||
for (i=0; i<n; i++) {
|
||||
gf_mul(product, table[i]->a, zis[i]);
|
||||
gf_strong_reduce(product);
|
||||
gf_copy(table[i]->a, product);
|
||||
|
||||
gf_mul(product, table[i]->b, zis[i]);
|
||||
gf_strong_reduce(product);
|
||||
gf_copy(table[i]->b, product);
|
||||
|
||||
gf_mul(product, table[i]->c, zis[i]);
|
||||
gf_strong_reduce(product);
|
||||
gf_copy(table[i]->c, product);
|
||||
}
|
||||
|
||||
OPENSSL_cleanse(product,sizeof(product));
|
||||
}
|
||||
|
||||
void API_NS(precompute) (
|
||||
precomputed_s *table,
|
||||
const point_t base
|
||||
) {
|
||||
const unsigned int n = COMBS_N, t = COMBS_T, s = COMBS_S;
|
||||
assert(n*t*s >= SCALAR_BITS);
|
||||
|
||||
point_t working, start, doubles[t-1];
|
||||
API_NS(point_copy)(working, base);
|
||||
pniels_t pn_tmp;
|
||||
|
||||
gf zs[n<<(t-1)], zis[n<<(t-1)];
|
||||
|
||||
unsigned int i,j,k;
|
||||
|
||||
/* Compute n tables */
|
||||
for (i=0; i<n; i++) {
|
||||
|
||||
/* Doubling phase */
|
||||
for (j=0; j<t; j++) {
|
||||
if (j) API_NS(point_add)(start, start, working);
|
||||
else API_NS(point_copy)(start, working);
|
||||
|
||||
if (j==t-1 && i==n-1) break;
|
||||
|
||||
point_double_internal(working, working,0);
|
||||
if (j<t-1) API_NS(point_copy)(doubles[j], working);
|
||||
|
||||
for (k=0; k<s-1; k++)
|
||||
point_double_internal(working, working, k<s-2);
|
||||
}
|
||||
|
||||
/* Gray-code phase */
|
||||
for (j=0;; j++) {
|
||||
int gray = j ^ (j>>1);
|
||||
int idx = (((i+1)<<(t-1))-1) ^ gray;
|
||||
|
||||
pt_to_pniels(pn_tmp, start);
|
||||
memcpy(table->table[idx], pn_tmp->n, sizeof(pn_tmp->n));
|
||||
gf_copy(zs[idx], pn_tmp->z);
|
||||
|
||||
if (j >= (1u<<(t-1)) - 1) break;
|
||||
int delta = (j+1) ^ ((j+1)>>1) ^ gray;
|
||||
|
||||
for (k=0; delta>1; k++)
|
||||
delta >>=1;
|
||||
|
||||
if (gray & (1<<k)) {
|
||||
API_NS(point_add)(start, start, doubles[k]);
|
||||
} else {
|
||||
API_NS(point_sub)(start, start, doubles[k]);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
batch_normalize_niels(table->table,(const gf *)zs,zis,n<<(t-1));
|
||||
|
||||
OPENSSL_cleanse(zs,sizeof(zs));
|
||||
OPENSSL_cleanse(zis,sizeof(zis));
|
||||
OPENSSL_cleanse(pn_tmp,sizeof(pn_tmp));
|
||||
OPENSSL_cleanse(working,sizeof(working));
|
||||
OPENSSL_cleanse(start,sizeof(start));
|
||||
OPENSSL_cleanse(doubles,sizeof(doubles));
|
||||
}
|
||||
|
||||
static DECAF_INLINE void
|
||||
constant_time_lookup_niels (
|
||||
niels_s *__restrict__ ni,
|
||||
@ -1015,33 +362,6 @@ void API_NS(precomputed_scalarmul) (
|
||||
OPENSSL_cleanse(scalar1x,sizeof(scalar1x));
|
||||
}
|
||||
|
||||
void API_NS(point_cond_sel) (
|
||||
point_t out,
|
||||
const point_t a,
|
||||
const point_t b,
|
||||
decaf_bool_t pick_b
|
||||
) {
|
||||
constant_time_select(out,a,b,sizeof(point_t),bool_to_mask(pick_b),0);
|
||||
}
|
||||
|
||||
/* FUTURE: restore Curve25519 Montgomery ladder? */
|
||||
decaf_error_t API_NS(direct_scalarmul) (
|
||||
uint8_t scaled[SER_BYTES],
|
||||
const uint8_t base[SER_BYTES],
|
||||
const scalar_t scalar,
|
||||
decaf_bool_t allow_identity,
|
||||
decaf_bool_t short_circuit
|
||||
) {
|
||||
point_t basep;
|
||||
decaf_error_t succ = API_NS(point_decode)(basep, base, allow_identity);
|
||||
if (short_circuit && succ != DECAF_SUCCESS) return succ;
|
||||
API_NS(point_cond_sel)(basep, API_NS(point_base), basep, succ);
|
||||
API_NS(point_scalarmul)(basep, basep, scalar);
|
||||
API_NS(point_encode)(scaled, basep);
|
||||
API_NS(point_destroy)(basep);
|
||||
return succ;
|
||||
}
|
||||
|
||||
void API_NS(point_mul_by_ratio_and_encode_like_eddsa) (
|
||||
uint8_t enc[DECAF_EDDSA_448_PUBLIC_BYTES],
|
||||
const point_t p
|
||||
@ -1482,32 +802,6 @@ prepare_wnaf_table(
|
||||
|
||||
extern const gf API_NS(precomputed_wnaf_as_fe)[];
|
||||
static const niels_t *API_NS(wnaf_base) = (const niels_t *)API_NS(precomputed_wnaf_as_fe);
|
||||
const size_t API_NS(sizeof_precomputed_wnafs) __attribute((visibility("hidden")))
|
||||
= sizeof(niels_t)<<DECAF_WNAF_FIXED_TABLE_BITS;
|
||||
|
||||
void API_NS(precompute_wnafs) (
|
||||
niels_t out[1<<DECAF_WNAF_FIXED_TABLE_BITS],
|
||||
const point_t base
|
||||
) __attribute__ ((visibility ("hidden")));
|
||||
|
||||
void API_NS(precompute_wnafs) (
|
||||
niels_t out[1<<DECAF_WNAF_FIXED_TABLE_BITS],
|
||||
const point_t base
|
||||
) {
|
||||
pniels_t tmp[1<<DECAF_WNAF_FIXED_TABLE_BITS];
|
||||
gf zs[1<<DECAF_WNAF_FIXED_TABLE_BITS], zis[1<<DECAF_WNAF_FIXED_TABLE_BITS];
|
||||
int i;
|
||||
prepare_wnaf_table(tmp,base,DECAF_WNAF_FIXED_TABLE_BITS);
|
||||
for (i=0; i<1<<DECAF_WNAF_FIXED_TABLE_BITS; i++) {
|
||||
memcpy(out[i], tmp[i]->n, sizeof(niels_t));
|
||||
gf_copy(zs[i], tmp[i]->z);
|
||||
}
|
||||
batch_normalize_niels(out, (const gf *)zs, zis, 1<<DECAF_WNAF_FIXED_TABLE_BITS);
|
||||
|
||||
OPENSSL_cleanse(tmp,sizeof(tmp));
|
||||
OPENSSL_cleanse(zs,sizeof(zs));
|
||||
OPENSSL_cleanse(zis,sizeof(zis));
|
||||
}
|
||||
|
||||
void API_NS(base_double_scalarmul_non_secret) (
|
||||
point_t combo,
|
||||
@ -1586,12 +880,6 @@ void API_NS(point_destroy) (
|
||||
OPENSSL_cleanse(point, sizeof(point_t));
|
||||
}
|
||||
|
||||
void API_NS(precomputed_destroy) (
|
||||
precomputed_s *pre
|
||||
) {
|
||||
OPENSSL_cleanse(pre, API_NS(sizeof_precomputed_s));
|
||||
}
|
||||
|
||||
int X448(uint8_t out_shared_key[56], const uint8_t private_key[56],
|
||||
const uint8_t peer_public_value[56])
|
||||
{
|
||||
|
@ -4,12 +4,6 @@
|
||||
#include "point_448.h"
|
||||
|
||||
#define API_NS(_id) decaf_448_##_id
|
||||
const API_NS(point_t) API_NS(point_base) = {{
|
||||
{FIELD_LITERAL(0x0000000000000000,0x0000000000000000,0x0000000000000000,0x0080000000000000,0x00fffffffffffffe,0x00ffffffffffffff,0x00ffffffffffffff,0x007fffffffffffff)},
|
||||
{FIELD_LITERAL(0x006079b4dfdd4a64,0x000c1e3ab470a1c8,0x0044d73f48e5199b,0x0050452714141818,0x004c74c393d5242c,0x0024080526437050,0x00d48d06c13078ca,0x008508de14f04286)},
|
||||
{FIELD_LITERAL(0x0000000000000001,0x0000000000000000,0x0000000000000000,0x0000000000000000,0x0000000000000000,0x0000000000000000,0x0000000000000000,0x0000000000000000)},
|
||||
{FIELD_LITERAL(0x00e3c816dc198105,0x0062071833f4e093,0x004dde98e3421403,0x00a319b57519c985,0x00794be956382384,0x00e1ddc2b86da60f,0x0050e23d5682a9ff,0x006d3669e173c6a4)}
|
||||
}};
|
||||
const gf API_NS(precomputed_base_as_fe)[240]
|
||||
VECTOR_ALIGNED __attribute__((visibility("hidden"))) = {
|
||||
{FIELD_LITERAL(0x00cc3b062366f4cc,0x003d6e34e314aa3c,0x00d51c0a7521774d,0x0094e060eec6ab8b,0x00d21291b4d80082,0x00befed12b55ef1e,0x00c3dd2df5c94518,0x00e0a7b112b8d4e6)},
|
||||
|
@ -77,9 +77,6 @@ struct decaf_448_precomputed_s;
|
||||
/** Precomputed table based on a point. Can be trivial implementation. */
|
||||
typedef struct decaf_448_precomputed_s decaf_448_precomputed_s;
|
||||
|
||||
/** Size and alignment of precomputed point tables. */
|
||||
extern const size_t decaf_448_sizeof_precomputed_s DECAF_API_VIS, decaf_448_alignof_precomputed_s DECAF_API_VIS;
|
||||
|
||||
/** Scalar is stored packed, because we don't need the speed. */
|
||||
typedef struct decaf_448_scalar_s {
|
||||
/** @cond internal */
|
||||
@ -234,37 +231,6 @@ void decaf_448_scalar_set_unsigned (
|
||||
uint64_t a
|
||||
) DECAF_API_VIS DECAF_NONNULL;
|
||||
|
||||
/**
|
||||
* @brief Encode a point as a sequence of bytes.
|
||||
*
|
||||
* @param [out] ser The byte representation of the point.
|
||||
* @param [in] pt The point to encode.
|
||||
*/
|
||||
void decaf_448_point_encode (
|
||||
uint8_t ser[DECAF_448_SER_BYTES],
|
||||
const decaf_448_point_t pt
|
||||
) DECAF_API_VIS DECAF_NONNULL DECAF_NOINLINE;
|
||||
|
||||
/**
|
||||
* @brief Decode a point from a sequence of bytes.
|
||||
*
|
||||
* Every point has a unique encoding, so not every
|
||||
* sequence of bytes is a valid encoding. If an invalid
|
||||
* encoding is given, the output is undefined.
|
||||
*
|
||||
* @param [out] pt The decoded point.
|
||||
* @param [in] ser The serialized version of the point.
|
||||
* @param [in] allow_identity DECAF_TRUE if the identity is a legal input.
|
||||
* @retval DECAF_SUCCESS The decoding succeeded.
|
||||
* @retval DECAF_FAILURE The decoding didn't succeed, because
|
||||
* ser does not represent a point.
|
||||
*/
|
||||
decaf_error_t decaf_448_point_decode (
|
||||
decaf_448_point_t pt,
|
||||
const uint8_t ser[DECAF_448_SER_BYTES],
|
||||
decaf_bool_t allow_identity
|
||||
) DECAF_API_VIS DECAF_WARN_UNUSED DECAF_NONNULL DECAF_NOINLINE;
|
||||
|
||||
/**
|
||||
* @brief Copy a point. The input and output may alias,
|
||||
* in which case this function does nothing.
|
||||
@ -293,21 +259,6 @@ decaf_bool_t decaf_448_point_eq (
|
||||
const decaf_448_point_t b
|
||||
) DECAF_API_VIS DECAF_WARN_UNUSED DECAF_NONNULL DECAF_NOINLINE;
|
||||
|
||||
/**
|
||||
* @brief Add two points to produce a third point. The
|
||||
* input points and output point can be pointers to the same
|
||||
* memory.
|
||||
*
|
||||
* @param [out] sum The sum a+b.
|
||||
* @param [in] a An addend.
|
||||
* @param [in] b An addend.
|
||||
*/
|
||||
void decaf_448_point_add (
|
||||
decaf_448_point_t sum,
|
||||
const decaf_448_point_t a,
|
||||
const decaf_448_point_t b
|
||||
) DECAF_API_VIS DECAF_NONNULL;
|
||||
|
||||
/**
|
||||
* @brief Double a point. Equivalent to
|
||||
* decaf_448_point_add(two_a,a,a), but potentially faster.
|
||||
@ -320,71 +271,6 @@ void decaf_448_point_double (
|
||||
const decaf_448_point_t a
|
||||
) DECAF_API_VIS DECAF_NONNULL;
|
||||
|
||||
/**
|
||||
* @brief Subtract two points to produce a third point. The
|
||||
* input points and output point can be pointers to the same
|
||||
* memory.
|
||||
*
|
||||
* @param [out] diff The difference a-b.
|
||||
* @param [in] a The minuend.
|
||||
* @param [in] b The subtrahend.
|
||||
*/
|
||||
void decaf_448_point_sub (
|
||||
decaf_448_point_t diff,
|
||||
const decaf_448_point_t a,
|
||||
const decaf_448_point_t b
|
||||
) DECAF_API_VIS DECAF_NONNULL;
|
||||
|
||||
/**
|
||||
* @brief Negate a point to produce another point. The input
|
||||
* and output points can use the same memory.
|
||||
*
|
||||
* @param [out] nega The negated input point
|
||||
* @param [in] a The input point.
|
||||
*/
|
||||
void decaf_448_point_negate (
|
||||
decaf_448_point_t nega,
|
||||
const decaf_448_point_t a
|
||||
) DECAF_API_VIS DECAF_NONNULL;
|
||||
|
||||
/**
|
||||
* @brief Multiply a base point by a scalar: scaled = scalar*base.
|
||||
*
|
||||
* @param [out] scaled The scaled point base*scalar
|
||||
* @param [in] base The point to be scaled.
|
||||
* @param [in] scalar The scalar to multiply by.
|
||||
*/
|
||||
void decaf_448_point_scalarmul (
|
||||
decaf_448_point_t scaled,
|
||||
const decaf_448_point_t base,
|
||||
const decaf_448_scalar_t scalar
|
||||
) DECAF_API_VIS DECAF_NONNULL DECAF_NOINLINE;
|
||||
|
||||
/**
|
||||
* @brief Multiply a base point by a scalar: scaled = scalar*base.
|
||||
* This function operates directly on serialized forms.
|
||||
*
|
||||
* @warning This function is experimental. It may not be supported
|
||||
* long-term.
|
||||
*
|
||||
* @param [out] scaled The scaled point base*scalar
|
||||
* @param [in] base The point to be scaled.
|
||||
* @param [in] scalar The scalar to multiply by.
|
||||
* @param [in] allow_identity Allow the input to be the identity.
|
||||
* @param [in] short_circuit Allow a fast return if the input is illegal.
|
||||
*
|
||||
* @retval DECAF_SUCCESS The scalarmul succeeded.
|
||||
* @retval DECAF_FAILURE The scalarmul didn't succeed, because
|
||||
* base does not represent a point.
|
||||
*/
|
||||
decaf_error_t decaf_448_direct_scalarmul (
|
||||
uint8_t scaled[DECAF_448_SER_BYTES],
|
||||
const uint8_t base[DECAF_448_SER_BYTES],
|
||||
const decaf_448_scalar_t scalar,
|
||||
decaf_bool_t allow_identity,
|
||||
decaf_bool_t short_circuit
|
||||
) DECAF_API_VIS DECAF_NONNULL DECAF_WARN_UNUSED DECAF_NOINLINE;
|
||||
|
||||
/**
|
||||
* @brief RFC 7748 Diffie-Hellman scalarmul. This function uses a different
|
||||
* (non-Decaf) encoding.
|
||||
@ -479,49 +365,6 @@ void decaf_448_precomputed_scalarmul (
|
||||
const decaf_448_scalar_t scalar
|
||||
) DECAF_API_VIS DECAF_NONNULL DECAF_NOINLINE;
|
||||
|
||||
/**
|
||||
* @brief Multiply two base points by two scalars:
|
||||
* scaled = scalar1*base1 + scalar2*base2.
|
||||
*
|
||||
* Equivalent to two calls to decaf_448_point_scalarmul, but may be
|
||||
* faster.
|
||||
*
|
||||
* @param [out] combo The linear combination scalar1*base1 + scalar2*base2.
|
||||
* @param [in] base1 A first point to be scaled.
|
||||
* @param [in] scalar1 A first scalar to multiply by.
|
||||
* @param [in] base2 A second point to be scaled.
|
||||
* @param [in] scalar2 A second scalar to multiply by.
|
||||
*/
|
||||
void decaf_448_point_double_scalarmul (
|
||||
decaf_448_point_t combo,
|
||||
const decaf_448_point_t base1,
|
||||
const decaf_448_scalar_t scalar1,
|
||||
const decaf_448_point_t base2,
|
||||
const decaf_448_scalar_t scalar2
|
||||
) DECAF_API_VIS DECAF_NONNULL DECAF_NOINLINE;
|
||||
|
||||
/**
|
||||
* Multiply one base point by two scalars:
|
||||
*
|
||||
* a1 = scalar1 * base
|
||||
* a2 = scalar2 * base
|
||||
*
|
||||
* Equivalent to two calls to decaf_448_point_scalarmul, but may be
|
||||
* faster.
|
||||
*
|
||||
* @param [out] a1 The first multiple. It may be the same as the input point.
|
||||
* @param [out] a2 The second multiple. It may be the same as the input point.
|
||||
* @param [in] base1 A point to be scaled.
|
||||
* @param [in] scalar1 A first scalar to multiply by.
|
||||
* @param [in] scalar2 A second scalar to multiply by.
|
||||
*/
|
||||
void decaf_448_point_dual_scalarmul (
|
||||
decaf_448_point_t a1,
|
||||
decaf_448_point_t a2,
|
||||
const decaf_448_point_t base1,
|
||||
const decaf_448_scalar_t scalar1,
|
||||
const decaf_448_scalar_t scalar2
|
||||
) DECAF_API_VIS DECAF_NONNULL DECAF_NOINLINE;
|
||||
|
||||
/**
|
||||
* @brief Multiply two base points by two scalars:
|
||||
@ -545,22 +388,6 @@ void decaf_448_base_double_scalarmul_non_secret (
|
||||
const decaf_448_scalar_t scalar2
|
||||
) DECAF_API_VIS DECAF_NONNULL DECAF_NOINLINE;
|
||||
|
||||
/**
|
||||
* @brief Constant-time decision between two points. If pick_b
|
||||
* is zero, out = a; else out = b.
|
||||
*
|
||||
* @param [out] out The output. It may be the same as either input.
|
||||
* @param [in] a Any point.
|
||||
* @param [in] b Any point.
|
||||
* @param [in] pick_b If nonzero, choose point b.
|
||||
*/
|
||||
void decaf_448_point_cond_sel (
|
||||
decaf_448_point_t out,
|
||||
const decaf_448_point_t a,
|
||||
const decaf_448_point_t b,
|
||||
decaf_word_t pick_b
|
||||
) DECAF_API_VIS DECAF_NONNULL DECAF_NOINLINE;
|
||||
|
||||
/**
|
||||
* @brief Constant-time decision between two scalars. If pick_b
|
||||
* is zero, out = a; else out = b.
|
||||
@ -588,32 +415,6 @@ decaf_bool_t decaf_448_point_valid (
|
||||
const decaf_448_point_t to_test
|
||||
) DECAF_API_VIS DECAF_WARN_UNUSED DECAF_NONNULL DECAF_NOINLINE;
|
||||
|
||||
/**
|
||||
* @brief Torque a point, for debugging purposes. The output
|
||||
* will be equal to the input.
|
||||
*
|
||||
* @param [out] q The point to torque.
|
||||
* @param [in] p The point to torque.
|
||||
*/
|
||||
void decaf_448_point_debugging_torque (
|
||||
decaf_448_point_t q,
|
||||
const decaf_448_point_t p
|
||||
) DECAF_API_VIS DECAF_NONNULL DECAF_NOINLINE;
|
||||
|
||||
/**
|
||||
* @brief Projectively scale a point, for debugging purposes.
|
||||
* The output will be equal to the input, and will be valid
|
||||
* even if the factor is zero.
|
||||
*
|
||||
* @param [out] q The point to scale.
|
||||
* @param [in] p The point to scale.
|
||||
* @param [in] factor Serialized GF factor to scale.
|
||||
*/
|
||||
void decaf_448_point_debugging_pscale (
|
||||
decaf_448_point_t q,
|
||||
const decaf_448_point_t p,
|
||||
const unsigned char factor[DECAF_448_SER_BYTES]
|
||||
) DECAF_API_VIS DECAF_NONNULL DECAF_NOINLINE;
|
||||
|
||||
/**
|
||||
* @brief Almost-Elligator-like hash to curve.
|
||||
@ -736,13 +537,6 @@ void decaf_448_point_destroy (
|
||||
decaf_448_point_t point
|
||||
) DECAF_NONNULL DECAF_API_VIS;
|
||||
|
||||
/**
|
||||
* @brief Overwrite precomputed table with zeros.
|
||||
*/
|
||||
void decaf_448_precomputed_destroy (
|
||||
decaf_448_precomputed_s *pre
|
||||
) DECAF_NONNULL DECAF_API_VIS;
|
||||
|
||||
#ifdef __cplusplus
|
||||
} /* extern "C" */
|
||||
#endif
|
||||
|
@ -110,71 +110,6 @@ void API_NS(scalar_mul) (
|
||||
sc_montmul(out,out,sc_r2);
|
||||
}
|
||||
|
||||
/* PERF: could implement this */
|
||||
static DECAF_INLINE void sc_montsqr (scalar_t out, const scalar_t a) {
|
||||
sc_montmul(out,a,a);
|
||||
}
|
||||
|
||||
decaf_error_t API_NS(scalar_invert) (
|
||||
scalar_t out,
|
||||
const scalar_t a
|
||||
) {
|
||||
/* Fermat's little theorem, sliding window.
|
||||
* Sliding window is fine here because the modulus isn't secret.
|
||||
*/
|
||||
const int SCALAR_WINDOW_BITS = 3;
|
||||
scalar_t precmp[1<<SCALAR_WINDOW_BITS];
|
||||
const int LAST = (1<<SCALAR_WINDOW_BITS)-1;
|
||||
|
||||
/* Precompute precmp = [a^1,a^3,...] */
|
||||
sc_montmul(precmp[0],a,sc_r2);
|
||||
if (LAST > 0) sc_montmul(precmp[LAST],precmp[0],precmp[0]);
|
||||
|
||||
int i;
|
||||
for (i=1; i<=LAST; i++) {
|
||||
sc_montmul(precmp[i],precmp[i-1],precmp[LAST]);
|
||||
}
|
||||
|
||||
/* Sliding window */
|
||||
unsigned residue = 0, trailing = 0, started = 0;
|
||||
for (i=SCALAR_BITS-1; i>=-SCALAR_WINDOW_BITS; i--) {
|
||||
|
||||
if (started) sc_montsqr(out,out);
|
||||
|
||||
decaf_word_t w = (i>=0) ? sc_p->limb[i/WBITS] : 0;
|
||||
if (i >= 0 && i<WBITS) {
|
||||
assert(w >= 2);
|
||||
w-=2;
|
||||
}
|
||||
|
||||
residue = (residue<<1) | ((w>>(i%WBITS))&1);
|
||||
if (residue>>SCALAR_WINDOW_BITS != 0) {
|
||||
assert(trailing == 0);
|
||||
trailing = residue;
|
||||
residue = 0;
|
||||
}
|
||||
|
||||
if (trailing > 0 && (trailing & ((1<<SCALAR_WINDOW_BITS)-1)) == 0) {
|
||||
if (started) {
|
||||
sc_montmul(out,out,precmp[trailing>>(SCALAR_WINDOW_BITS+1)]);
|
||||
} else {
|
||||
API_NS(scalar_copy)(out,precmp[trailing>>(SCALAR_WINDOW_BITS+1)]);
|
||||
started = 1;
|
||||
}
|
||||
trailing = 0;
|
||||
}
|
||||
trailing <<= 1;
|
||||
|
||||
}
|
||||
assert(residue==0);
|
||||
assert(trailing==0);
|
||||
|
||||
/* Demontgomerize */
|
||||
sc_montmul(out,out,API_NS(scalar_one));
|
||||
OPENSSL_cleanse(precmp, sizeof(precmp));
|
||||
return decaf_succeed_if(~API_NS(scalar_eq)(out,API_NS(scalar_zero)));
|
||||
}
|
||||
|
||||
void API_NS(scalar_sub) (
|
||||
scalar_t out,
|
||||
const scalar_t a,
|
||||
@ -198,34 +133,6 @@ void API_NS(scalar_add) (
|
||||
sc_subx(out, out->limb, sc_p, sc_p, chain);
|
||||
}
|
||||
|
||||
void
|
||||
API_NS(scalar_set_unsigned) (
|
||||
scalar_t out,
|
||||
uint64_t w
|
||||
) {
|
||||
memset(out,0,sizeof(scalar_t));
|
||||
unsigned int i = 0;
|
||||
for (; i<sizeof(uint64_t)/sizeof(decaf_word_t); i++) {
|
||||
out->limb[i] = w;
|
||||
#if DECAF_WORD_BITS < 64
|
||||
w >>= 8*sizeof(decaf_word_t);
|
||||
#endif
|
||||
}
|
||||
}
|
||||
|
||||
decaf_bool_t
|
||||
API_NS(scalar_eq) (
|
||||
const scalar_t a,
|
||||
const scalar_t b
|
||||
) {
|
||||
decaf_word_t diff = 0;
|
||||
unsigned int i;
|
||||
for (i=0; i<SCALAR_LIMBS; i++) {
|
||||
diff |= a->limb[i] ^ b->limb[i];
|
||||
}
|
||||
return mask_to_bool(word_is_zero(diff));
|
||||
}
|
||||
|
||||
static DECAF_INLINE void scalar_decode_short (
|
||||
scalar_t s,
|
||||
const unsigned char *ser,
|
||||
@ -314,15 +221,6 @@ void API_NS(scalar_encode)(
|
||||
}
|
||||
}
|
||||
|
||||
void API_NS(scalar_cond_sel) (
|
||||
scalar_t out,
|
||||
const scalar_t a,
|
||||
const scalar_t b,
|
||||
decaf_bool_t pick_b
|
||||
) {
|
||||
constant_time_select(out,a,b,sizeof(scalar_t),bool_to_mask(pick_b),sizeof(out->limb[0]));
|
||||
}
|
||||
|
||||
void API_NS(scalar_halve) (
|
||||
scalar_t out,
|
||||
const scalar_t a
|
||||
|
Loading…
Reference in New Issue
Block a user