diff options
Diffstat (limited to 'external_libs/python/pyzmq-14.7.0/bundled/libsodium/src/libsodium/crypto_sign/edwards25519sha512batch/ref/ge25519_edwards25519sha512batch.c')
-rw-r--r-- | external_libs/python/pyzmq-14.7.0/bundled/libsodium/src/libsodium/crypto_sign/edwards25519sha512batch/ref/ge25519_edwards25519sha512batch.c | 230 |
1 files changed, 230 insertions, 0 deletions
diff --git a/external_libs/python/pyzmq-14.7.0/bundled/libsodium/src/libsodium/crypto_sign/edwards25519sha512batch/ref/ge25519_edwards25519sha512batch.c b/external_libs/python/pyzmq-14.7.0/bundled/libsodium/src/libsodium/crypto_sign/edwards25519sha512batch/ref/ge25519_edwards25519sha512batch.c new file mode 100644 index 00000000..253b68f4 --- /dev/null +++ b/external_libs/python/pyzmq-14.7.0/bundled/libsodium/src/libsodium/crypto_sign/edwards25519sha512batch/ref/ge25519_edwards25519sha512batch.c @@ -0,0 +1,230 @@ +#include "fe25519.h" +#include "sc25519.h" +#include "ge25519.h" + +/* + * Arithmetic on the twisted Edwards curve -x^2 + y^2 = 1 + dx^2y^2 + * with d = -(121665/121666) = 37095705934669439343138083508754565189542113879843219016388785533085940283555 + * Base point: (15112221349535400772501151409588531511454012693041857206046113283949847762202,46316835694926478169428394003475163141307993866256225615783033603165251855960); + */ + +typedef struct +{ + fe25519 x; + fe25519 z; + fe25519 y; + fe25519 t; +} ge25519_p1p1; + +typedef struct +{ + fe25519 x; + fe25519 y; + fe25519 z; +} ge25519_p2; + +#define ge25519_p3 ge25519 + +/* Windowsize for fixed-window scalar multiplication */ +#define WINDOWSIZE 2 /* Should be 1,2, or 4 */ +#define WINDOWMASK ((1<<WINDOWSIZE)-1) + +/* packed parameter d in the Edwards curve equation */ +static const unsigned char ecd[32] = {0xA3, 0x78, 0x59, 0x13, 0xCA, 0x4D, 0xEB, 0x75, 0xAB, 0xD8, 0x41, 0x41, 0x4D, 0x0A, 0x70, 0x00, + 0x98, 0xE8, 0x79, 0x77, 0x79, 0x40, 0xC7, 0x8C, 0x73, 0xFE, 0x6F, 0x2B, 0xEE, 0x6C, 0x03, 0x52}; + +/* Packed coordinates of the base point */ +static const unsigned char ge25519_base_x[32] = {0x1A, 0xD5, 0x25, 0x8F, 0x60, 0x2D, 0x56, 0xC9, 0xB2, 0xA7, 0x25, 0x95, 0x60, 0xC7, 0x2C, 0x69, + 0x5C, 0xDC, 0xD6, 0xFD, 0x31, 0xE2, 0xA4, 0xC0, 0xFE, 0x53, 0x6E, 0xCD, 0xD3, 0x36, 0x69, 0x21}; +static const unsigned char ge25519_base_y[32] = {0x58, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, + 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66}; +static const unsigned char ge25519_base_z[32] = {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; +static const unsigned char ge25519_base_t[32] = {0xA3, 0xDD, 0xB7, 0xA5, 0xB3, 0x8A, 0xDE, 0x6D, 0xF5, 0x52, 0x51, 0x77, 0x80, 0x9F, 0xF0, 0x20, + 0x7D, 0xE3, 0xAB, 0x64, 0x8E, 0x4E, 0xEA, 0x66, 0x65, 0x76, 0x8B, 0xD7, 0x0F, 0x5F, 0x87, 0x67}; + +/* Packed coordinates of the neutral element */ +static const unsigned char ge25519_neutral_x[32] = {0}; +static const unsigned char ge25519_neutral_y[32] = {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; +static const unsigned char ge25519_neutral_z[32] = {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; +static const unsigned char ge25519_neutral_t[32] = {0}; + +static void p1p1_to_p2(ge25519_p2 *r, const ge25519_p1p1 *p) +{ + fe25519_mul(&r->x, &p->x, &p->t); + fe25519_mul(&r->y, &p->y, &p->z); + fe25519_mul(&r->z, &p->z, &p->t); +} + +static void p1p1_to_p3(ge25519_p3 *r, const ge25519_p1p1 *p) +{ + p1p1_to_p2((ge25519_p2 *)r, p); + fe25519_mul(&r->t, &p->x, &p->y); +} + +/* Constant-time version of: if(b) r = p */ +static void cmov_p3(ge25519_p3 *r, const ge25519_p3 *p, unsigned char b) +{ + fe25519_cmov(&r->x, &p->x, b); + fe25519_cmov(&r->y, &p->y, b); + fe25519_cmov(&r->z, &p->z, b); + fe25519_cmov(&r->t, &p->t, b); +} + +/* See http://www.hyperelliptic.org/EFD/g1p/auto-twisted-extended-1.html#doubling-dbl-2008-hwcd */ +static void dbl_p1p1(ge25519_p1p1 *r, const ge25519_p2 *p) +{ + fe25519 a,b,c,d; + fe25519_square(&a, &p->x); + fe25519_square(&b, &p->y); + fe25519_square(&c, &p->z); + fe25519_add(&c, &c, &c); + fe25519_neg(&d, &a); + + fe25519_add(&r->x, &p->x, &p->y); + fe25519_square(&r->x, &r->x); + fe25519_sub(&r->x, &r->x, &a); + fe25519_sub(&r->x, &r->x, &b); + fe25519_add(&r->z, &d, &b); + fe25519_sub(&r->t, &r->z, &c); + fe25519_sub(&r->y, &d, &b); +} + +static void add_p1p1(ge25519_p1p1 *r, const ge25519_p3 *p, const ge25519_p3 *q) +{ + fe25519 a, b, c, d, t, fd; + fe25519_unpack(&fd, ecd); + + fe25519_sub(&a, &p->y, &p->x); // A = (Y1-X1)*(Y2-X2) + fe25519_sub(&t, &q->y, &q->x); + fe25519_mul(&a, &a, &t); + fe25519_add(&b, &p->x, &p->y); // B = (Y1+X1)*(Y2+X2) + fe25519_add(&t, &q->x, &q->y); + fe25519_mul(&b, &b, &t); + fe25519_mul(&c, &p->t, &q->t); //C = T1*k*T2 + fe25519_mul(&c, &c, &fd); + fe25519_add(&c, &c, &c); //XXX: Can save this addition by precomputing 2*ecd + fe25519_mul(&d, &p->z, &q->z); //D = Z1*2*Z2 + fe25519_add(&d, &d, &d); + fe25519_sub(&r->x, &b, &a); // E = B-A + fe25519_sub(&r->t, &d, &c); // F = D-C + fe25519_add(&r->z, &d, &c); // G = D+C + fe25519_add(&r->y, &b, &a); // H = B+A +} + +/* ******************************************************************** + * EXPORTED FUNCTIONS + ******************************************************************** */ + +/* return 0 on success, -1 otherwise */ +int ge25519_unpack_vartime(ge25519_p3 *r, const unsigned char p[32]) +{ + int ret; + fe25519 t, fd; + unsigned char par; + + fe25519_setone(&r->z); + fe25519_unpack(&fd, ecd); + par = p[31] >> 7; + fe25519_unpack(&r->y, p); + fe25519_square(&r->x, &r->y); + fe25519_mul(&t, &r->x, &fd); + fe25519_sub(&r->x, &r->x, &r->z); + fe25519_add(&t, &r->z, &t); + fe25519_invert(&t, &t); + fe25519_mul(&r->x, &r->x, &t); + ret = fe25519_sqrt_vartime(&r->x, &r->x, par); + fe25519_mul(&r->t, &r->x, &r->y); + return ret; +} + +void ge25519_pack(unsigned char r[32], const ge25519_p3 *p) +{ + fe25519 tx, ty, zi; + fe25519_invert(&zi, &p->z); + fe25519_mul(&tx, &p->x, &zi); + fe25519_mul(&ty, &p->y, &zi); + fe25519_pack(r, &ty); + r[31] ^= fe25519_getparity(&tx) << 7; +} + +void ge25519_add(ge25519_p3 *r, const ge25519_p3 *p, const ge25519_p3 *q) +{ + ge25519_p1p1 grp1p1; + add_p1p1(&grp1p1, p, q); + p1p1_to_p3(r, &grp1p1); +} + +void ge25519_double(ge25519_p3 *r, const ge25519_p3 *p) +{ + ge25519_p1p1 grp1p1; + dbl_p1p1(&grp1p1, (const ge25519_p2 *)p); + p1p1_to_p3(r, &grp1p1); +} + +void ge25519_scalarmult(ge25519_p3 *r, const ge25519_p3 *p, const sc25519 *s) +{ + int i,j,k; + ge25519_p3 g; + ge25519_p3 pre[(1 << WINDOWSIZE)]; + ge25519_p3 t; + ge25519_p1p1 tp1p1; + unsigned char w; + unsigned char sb[32]; + + fe25519_unpack(&g.x, ge25519_neutral_x); + fe25519_unpack(&g.y, ge25519_neutral_y); + fe25519_unpack(&g.z, ge25519_neutral_z); + fe25519_unpack(&g.t, ge25519_neutral_t); + + sc25519_to32bytes(sb, s); + + // Precomputation + pre[0] = g; + pre[1] = *p; + for(i=2;i<(1<<WINDOWSIZE);i+=2) + { + dbl_p1p1(&tp1p1, (ge25519_p2 *)(pre+i/2)); + p1p1_to_p3(pre+i, &tp1p1); + add_p1p1(&tp1p1, pre+i, pre+1); + p1p1_to_p3(pre+i+1, &tp1p1); + } + + // Fixed-window scalar multiplication + for(i=32;i>0;i--) + { + for(j=8-WINDOWSIZE;j>=0;j-=WINDOWSIZE) + { + for(k=0;k<WINDOWSIZE-1;k++) + { + dbl_p1p1(&tp1p1, (ge25519_p2 *)&g); + p1p1_to_p2((ge25519_p2 *)&g, &tp1p1); + } + dbl_p1p1(&tp1p1, (ge25519_p2 *)&g); + p1p1_to_p3(&g, &tp1p1); + // Cache-timing resistant loading of precomputed value: + w = (sb[i-1]>>j) & WINDOWMASK; + t = pre[0]; + for(k=1;k<(1<<WINDOWSIZE);k++) + cmov_p3(&t, &pre[k], k==w); + + add_p1p1(&tp1p1, &g, &t); + if(j != 0) p1p1_to_p2((ge25519_p2 *)&g, &tp1p1); + else p1p1_to_p3(&g, &tp1p1); /* convert to p3 representation at the end */ + } + } + r->x = g.x; + r->y = g.y; + r->z = g.z; + r->t = g.t; +} + +void ge25519_scalarmult_base(ge25519_p3 *r, const sc25519 *s) +{ + /* XXX: Better algorithm for known-base-point scalar multiplication */ + ge25519_p3 t; + fe25519_unpack(&t.x, ge25519_base_x); + fe25519_unpack(&t.y, ge25519_base_y); + fe25519_unpack(&t.z, ge25519_base_z); + fe25519_unpack(&t.t, ge25519_base_t); + ge25519_scalarmult(r, &t, s); +} |