/* * Ed25519 * (C) 2017 Ribose Inc * * Based on the public domain code from SUPERCOP ref10 by * Peter Schwabe, Daniel J. Bernstein, Niels Duif, Tanja Lange, Bo-Yin Yang * * Botan is released under the Simplified BSD License (see license.txt) */ #include namespace Botan { /* Input: a[0]+256*a[1]+...+256^31*a[31] = a b[0]+256*b[1]+...+256^31*b[31] = b c[0]+256*c[1]+...+256^31*c[31] = c Output: s[0]+256*s[1]+...+256^31*s[31] = (ab+c) mod l where l = 2^252 + 27742317777372353535851937790883648493. */ void sc_muladd(uint8_t* s, const uint8_t* a, const uint8_t* b, const uint8_t* c) { const int32_t MASK = 0x1fffff; const int64_t a0 = MASK & load_3(a); const int64_t a1 = MASK & (load_4(a + 2) >> 5); const int64_t a2 = MASK & (load_3(a + 5) >> 2); const int64_t a3 = MASK & (load_4(a + 7) >> 7); const int64_t a4 = MASK & (load_4(a + 10) >> 4); const int64_t a5 = MASK & (load_3(a + 13) >> 1); const int64_t a6 = MASK & (load_4(a + 15) >> 6); const int64_t a7 = MASK & (load_3(a + 18) >> 3); const int64_t a8 = MASK & load_3(a + 21); const int64_t a9 = MASK & (load_4(a + 23) >> 5); const int64_t a10 = MASK & (load_3(a + 26) >> 2); const int64_t a11 = (load_4(a + 28) >> 7); const int64_t b0 = MASK & load_3(b); const int64_t b1 = MASK & (load_4(b + 2) >> 5); const int64_t b2 = MASK & (load_3(b + 5) >> 2); const int64_t b3 = MASK & (load_4(b + 7) >> 7); const int64_t b4 = MASK & (load_4(b + 10) >> 4); const int64_t b5 = MASK & (load_3(b + 13) >> 1); const int64_t b6 = MASK & (load_4(b + 15) >> 6); const int64_t b7 = MASK & (load_3(b + 18) >> 3); const int64_t b8 = MASK & load_3(b + 21); const int64_t b9 = MASK & (load_4(b + 23) >> 5); const int64_t b10 = MASK & (load_3(b + 26) >> 2); const int64_t b11 = (load_4(b + 28) >> 7); const int64_t c0 = MASK & load_3(c); const int64_t c1 = MASK & (load_4(c + 2) >> 5); const int64_t c2 = MASK & (load_3(c + 5) >> 2); const int64_t c3 = MASK & (load_4(c + 7) >> 7); const int64_t c4 = MASK & (load_4(c + 10) >> 4); const int64_t c5 = MASK & (load_3(c + 13) >> 1); const int64_t c6 = MASK & (load_4(c + 15) >> 6); const int64_t c7 = MASK & (load_3(c + 18) >> 3); const int64_t c8 = MASK & load_3(c + 21); const int64_t c9 = MASK & (load_4(c + 23) >> 5); const int64_t c10 = MASK & (load_3(c + 26) >> 2); const int64_t c11 = (load_4(c + 28) >> 7); int64_t s0 = c0 + a0*b0; int64_t s1 = c1 + a0*b1 + a1*b0; int64_t s2 = c2 + a0*b2 + a1*b1 + a2*b0; int64_t s3 = c3 + a0*b3 + a1*b2 + a2*b1 + a3*b0; int64_t s4 = c4 + a0*b4 + a1*b3 + a2*b2 + a3*b1 + a4*b0; int64_t s5 = c5 + a0*b5 + a1*b4 + a2*b3 + a3*b2 + a4*b1 + a5*b0; int64_t s6 = c6 + a0*b6 + a1*b5 + a2*b4 + a3*b3 + a4*b2 + a5*b1 + a6*b0; int64_t s7 = c7 + a0*b7 + a1*b6 + a2*b5 + a3*b4 + a4*b3 + a5*b2 + a6*b1 + a7*b0; int64_t s8 = c8 + a0*b8 + a1*b7 + a2*b6 + a3*b5 + a4*b4 + a5*b3 + a6*b2 + a7*b1 + a8*b0; int64_t s9 = c9 + a0*b9 + a1*b8 + a2*b7 + a3*b6 + a4*b5 + a5*b4 + a6*b3 + a7*b2 + a8*b1 + a9*b0; int64_t s10 = c10 + a0*b10 + a1*b9 + a2*b8 + a3*b7 + a4*b6 + a5*b5 + a6*b4 + a7*b3 + a8*b2 + a9*b1 + a10*b0; int64_t s11 = c11 + a0*b11 + a1*b10 + a2*b9 + a3*b8 + a4*b7 + a5*b6 + a6*b5 + a7*b4 + a8*b3 + a9*b2 + a10*b1 + a11*b0; int64_t s12 = a1*b11 + a2*b10 + a3*b9 + a4*b8 + a5*b7 + a6*b6 + a7*b5 + a8*b4 + a9*b3 + a10*b2 + a11*b1; int64_t s13 = a2*b11 + a3*b10 + a4*b9 + a5*b8 + a6*b7 + a7*b6 + a8*b5 + a9*b4 + a10*b3 + a11*b2; int64_t s14 = a3*b11 + a4*b10 + a5*b9 + a6*b8 + a7*b7 + a8*b6 + a9*b5 + a10*b4 + a11*b3; int64_t s15 = a4*b11 + a5*b10 + a6*b9 + a7*b8 + a8*b7 + a9*b6 + a10*b5 + a11*b4; int64_t s16 = a5*b11 + a6*b10 + a7*b9 + a8*b8 + a9*b7 + a10*b6 + a11*b5; int64_t s17 = a6*b11 + a7*b10 + a8*b9 + a9*b8 + a10*b7 + a11*b6; int64_t s18 = a7*b11 + a8*b10 + a9*b9 + a10*b8 + a11*b7; int64_t s19 = a8*b11 + a9*b10 + a10*b9 + a11*b8; int64_t s20 = a9*b11 + a10*b10 + a11*b9; int64_t s21 = a10*b11 + a11*b10; int64_t s22 = a11*b11; int64_t s23 = 0; carry<21>(s0, s1); carry<21>(s2, s3); carry<21>(s4, s5); carry<21>(s6, s7); carry<21>(s8, s9); carry<21>(s10, s11); carry<21>(s12, s13); carry<21>(s14, s15); carry<21>(s16, s17); carry<21>(s18, s19); carry<21>(s20, s21); carry<21>(s22, s23); carry<21>(s1, s2); carry<21>(s3, s4); carry<21>(s5, s6); carry<21>(s7, s8); carry<21>(s9, s10); carry<21>(s11, s12); carry<21>(s13, s14); carry<21>(s15, s16); carry<21>(s17, s18); carry<21>(s19, s20); carry<21>(s21, s22); redc_mul(s11, s12, s13, s14, s15, s16, s23); redc_mul(s10, s11, s12, s13, s14, s15, s22); redc_mul( s9, s10, s11, s12, s13, s14, s21); redc_mul( s8, s9, s10, s11, s12, s13, s20); redc_mul( s7, s8, s9, s10, s11, s12, s19); redc_mul( s6, s7, s8, s9, s10, s11, s18); carry<21>(s6, s7); carry<21>(s8, s9); carry<21>(s10, s11); carry<21>(s12, s13); carry<21>(s14, s15); carry<21>(s16, s17); carry<21>(s7, s8); carry<21>(s9, s10); carry<21>(s11, s12); carry<21>(s13, s14); carry<21>(s15, s16); redc_mul(s5, s6, s7, s8, s9, s10, s17); redc_mul(s4, s5, s6, s7, s8, s9, s16); redc_mul(s3, s4, s5, s6, s7, s8, s15); redc_mul(s2, s3, s4, s5, s6, s7, s14); redc_mul(s1, s2, s3, s4, s5, s6, s13); redc_mul(s0, s1, s2, s3, s4, s5, s12); carry<21>(s0, s1); carry<21>(s2, s3); carry<21>(s4, s5); carry<21>(s6, s7); carry<21>(s8, s9); carry<21>(s10, s11); carry<21>(s1, s2); carry<21>(s3, s4); carry<21>(s5, s6); carry<21>(s7, s8); carry<21>(s9, s10); carry<21>(s11, s12); redc_mul(s0, s1, s2, s3, s4, s5, s12); carry0<21>(s0, s1); carry0<21>(s1, s2); carry0<21>(s2, s3); carry0<21>(s3, s4); carry0<21>(s4, s5); carry0<21>(s5, s6); carry0<21>(s6, s7); carry0<21>(s7, s8); carry0<21>(s8, s9); carry0<21>(s9, s10); carry0<21>(s10, s11); carry0<21>(s11, s12); redc_mul(s0, s1, s2, s3, s4, s5, s12); carry0<21>(s0, s1); carry0<21>(s1, s2); carry0<21>(s2, s3); carry0<21>(s3, s4); carry0<21>(s4, s5); carry0<21>(s5, s6); carry0<21>(s6, s7); carry0<21>(s7, s8); carry0<21>(s8, s9); carry0<21>(s9, s10); carry0<21>(s10, s11); s[0] = s0 >> 0; s[1] = s0 >> 8; s[2] = (s0 >> 16) | (s1 << 5); s[3] = s1 >> 3; s[4] = s1 >> 11; s[5] = (s1 >> 19) | (s2 << 2); s[6] = s2 >> 6; s[7] = (s2 >> 14) | (s3 << 7); s[8] = s3 >> 1; s[9] = s3 >> 9; s[10] = (s3 >> 17) | (s4 << 4); s[11] = s4 >> 4; s[12] = s4 >> 12; s[13] = (s4 >> 20) | (s5 << 1); s[14] = s5 >> 7; s[15] = (s5 >> 15) | (s6 << 6); s[16] = s6 >> 2; s[17] = s6 >> 10; s[18] = (s6 >> 18) | (s7 << 3); s[19] = s7 >> 5; s[20] = s7 >> 13; s[21] = s8 >> 0; s[22] = s8 >> 8; s[23] = (s8 >> 16) | (s9 << 5); s[24] = s9 >> 3; s[25] = s9 >> 11; s[26] = (s9 >> 19) | (s10 << 2); s[27] = s10 >> 6; s[28] = (s10 >> 14) | (s11 << 7); s[29] = s11 >> 1; s[30] = s11 >> 9; s[31] = s11 >> 17; } }