/* ksdk_port.c * * Copyright (C) 2006-2020 wolfSSL Inc. * * This file is part of wolfSSL. * * wolfSSL is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * wolfSSL is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA */ #ifdef HAVE_CONFIG_H #include #endif #include #ifdef NO_INLINE #include #else #define WOLFSSL_MISC_INCLUDED #include #endif /* If FREESCALE_LTC_TFM or FREESCALE_LTC_ECC */ #if defined(FREESCALE_LTC_TFM) || defined(FREESCALE_LTC_ECC) #include #include #include #include #include #define ERROR_OUT(res) { ret = (res); goto done; } int ksdk_port_init(void) { #if defined(FREESCALE_LTC_TFM) LTC_Init(LTC0); #endif return 0; } /* Reverse array in memory (in place) */ static void ltc_reverse_array(uint8_t *src, size_t src_len) { unsigned int i; for (i = 0; i < src_len / 2; i++) { uint8_t tmp; tmp = src[i]; src[i] = src[src_len - 1 - i]; src[src_len - 1 - i] = tmp; } } #ifndef WOLFSSL_SP_MATH /* same as mp_to_unsigned_bin() with mp_reverse() skipped */ static int mp_to_unsigned_lsb_bin(mp_int *a, unsigned char *b) { int res; mp_int t; res = mp_init_copy(&t, a); if (res == MP_OKAY) { res = mp_to_unsigned_bin_at_pos(0, &t, b); if (res >= 0) res = 0; #ifndef USE_FAST_MATH mp_clear(&t); #endif } return res; } #endif static int ltc_get_lsb_bin_from_mp_int(uint8_t *dst, mp_int *A, uint16_t *psz) { int res; uint16_t sz; sz = mp_unsigned_bin_size(A); #ifndef WOLFSSL_SP_MATH res = mp_to_unsigned_lsb_bin(A, dst); /* result is lsbyte at lowest addr as required by LTC */ #else res = mp_to_unsigned_bin(A, dst); if (res == MP_OKAY) { ltc_reverse_array(dst, sz); } #endif *psz = sz; return res; } /* LTC TFM */ #if defined(FREESCALE_LTC_TFM) /* these function are used by wolfSSL upper layers (like RSA) */ /* c = a * b */ int mp_mul(mp_int *A, mp_int *B, mp_int *C) { int res = MP_OKAY; int szA, szB; szA = mp_unsigned_bin_size(A); szB = mp_unsigned_bin_size(B); /* if unsigned mul can fit into LTC PKHA let's use it, otherwise call software mul */ if ((szA <= LTC_MAX_INT_BYTES / 2) && (szB <= LTC_MAX_INT_BYTES / 2)) { int neg = 0; #ifndef WOLFSSL_SP_MATH neg = (A->sign == B->sign) ? MP_ZPOS : MP_NEG; #endif /* unsigned multiply */ uint8_t *ptrA = (uint8_t *)XMALLOC(LTC_MAX_INT_BYTES, 0, DYNAMIC_TYPE_BIGINT); uint8_t *ptrB = (uint8_t *)XMALLOC(LTC_MAX_INT_BYTES, 0, DYNAMIC_TYPE_BIGINT); uint8_t *ptrC = (uint8_t *)XMALLOC(LTC_MAX_INT_BYTES, 0, DYNAMIC_TYPE_BIGINT); if (ptrA && ptrB && ptrC) { uint16_t sizeA, sizeB; res = ltc_get_lsb_bin_from_mp_int(ptrA, A, &sizeA); if (res == MP_OKAY) res = ltc_get_lsb_bin_from_mp_int(ptrB, B, &sizeB); if (res == MP_OKAY) { XMEMSET(ptrC, 0xFF, LTC_MAX_INT_BYTES); LTC_PKHA_ModMul(LTC_BASE, ptrA, sizeA, ptrB, sizeB, ptrC, LTC_MAX_INT_BYTES, ptrB, &sizeB, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); ltc_reverse_array(ptrB, sizeB); res = mp_read_unsigned_bin(C, ptrB, sizeB); } } #ifndef WOLFSSL_SP_MATH /* fix sign */ C->sign = neg; #endif if (ptrA) { XFREE(ptrA, NULL, DYNAMIC_TYPE_BIGINT); } if (ptrB) { XFREE(ptrB, NULL, DYNAMIC_TYPE_BIGINT); } if (ptrC) { XFREE(ptrC, NULL, DYNAMIC_TYPE_BIGINT); } } else { #ifdef WOLFSSL_SP_MATH res = sp_mul(A, B, C); #else res = wolfcrypt_mp_mul(A, B, C); #endif } return res; } /* c = a mod b, 0 <= c < b */ int mp_mod(mp_int *a, mp_int *b, mp_int *c) { int res = MP_OKAY; #if defined(FREESCALE_LTC_TFM_RSA_4096_ENABLE) int szA, szB; szA = mp_unsigned_bin_size(a); szB = mp_unsigned_bin_size(b); if ((szA <= LTC_MAX_INT_BYTES) && (szB <= LTC_MAX_INT_BYTES)) { #endif /* FREESCALE_LTC_TFM_RSA_4096_ENABLE */ int neg = 0; uint8_t *ptrA = (uint8_t *)XMALLOC(LTC_MAX_INT_BYTES, 0, DYNAMIC_TYPE_BIGINT); uint8_t *ptrB = (uint8_t *)XMALLOC(LTC_MAX_INT_BYTES, 0, DYNAMIC_TYPE_BIGINT); uint8_t *ptrC = (uint8_t *)XMALLOC(LTC_MAX_INT_BYTES, 0, DYNAMIC_TYPE_BIGINT); #ifndef WOLFSSL_SP_MATH /* get sign for the result */ neg = (a->sign == b->sign) ? MP_ZPOS : MP_NEG; #endif /* get remainder of unsigned a divided by unsigned b */ if (ptrA && ptrB && ptrC) { uint16_t sizeA, sizeB, sizeC; res = ltc_get_lsb_bin_from_mp_int(ptrA, a, &sizeA); if (res == MP_OKAY) res = ltc_get_lsb_bin_from_mp_int(ptrB, b, &sizeB); if (res == MP_OKAY) { if (kStatus_Success == LTC_PKHA_ModRed(LTC_BASE, ptrA, sizeA, ptrB, sizeB, ptrC, &sizeC, kLTC_PKHA_IntegerArith)) { ltc_reverse_array(ptrC, sizeC); res = mp_read_unsigned_bin(c, ptrC, sizeC); } else { res = MP_VAL; } } } else { res = MP_MEM; } #ifndef WOLFSSL_SP_MATH /* fix sign */ c->sign = neg; #endif if (ptrA) { XFREE(ptrA, NULL, DYNAMIC_TYPE_BIGINT); } if (ptrB) { XFREE(ptrB, NULL, DYNAMIC_TYPE_BIGINT); } if (ptrC) { XFREE(ptrC, NULL, DYNAMIC_TYPE_BIGINT); } #if defined(FREESCALE_LTC_TFM_RSA_4096_ENABLE) } else { res = wolfcrypt_mp_mod(a, b, c); } #endif /* FREESCALE_LTC_TFM_RSA_4096_ENABLE */ return res; } /* c = 1/a (mod b) for odd b only */ int mp_invmod(mp_int *a, mp_int *b, mp_int *c) { int res = MP_OKAY; #if defined(FREESCALE_LTC_TFM_RSA_4096_ENABLE) int szA, szB; szA = mp_unsigned_bin_size(a); szB = mp_unsigned_bin_size(b); if ((szA <= LTC_MAX_INT_BYTES) && (szB <= LTC_MAX_INT_BYTES)) { #endif uint8_t *ptrA = (uint8_t *)XMALLOC(LTC_MAX_INT_BYTES, 0, DYNAMIC_TYPE_BIGINT); uint8_t *ptrB = (uint8_t *)XMALLOC(LTC_MAX_INT_BYTES, 0, DYNAMIC_TYPE_BIGINT); uint8_t *ptrC = (uint8_t *)XMALLOC(LTC_MAX_INT_BYTES, 0, DYNAMIC_TYPE_BIGINT); if (ptrA && ptrB && ptrC) { uint16_t sizeA, sizeB, sizeC; res = ltc_get_lsb_bin_from_mp_int(ptrA, a, &sizeA); if (res == MP_OKAY) res = ltc_get_lsb_bin_from_mp_int(ptrB, b, &sizeB); if (res == MP_OKAY) { if (kStatus_Success == LTC_PKHA_ModInv(LTC_BASE, ptrA, sizeA, ptrB, sizeB, ptrC, &sizeC, kLTC_PKHA_IntegerArith)) { ltc_reverse_array(ptrC, sizeC); res = mp_read_unsigned_bin(c, ptrC, sizeC); } else { res = MP_VAL; } } } else { res = MP_MEM; } #ifndef WOLFSSL_SP_MATH c->sign = a->sign; #endif if (ptrA) { XFREE(ptrA, NULL, DYNAMIC_TYPE_BIGINT); } if (ptrB) { XFREE(ptrB, NULL, DYNAMIC_TYPE_BIGINT); } if (ptrC) { XFREE(ptrC, NULL, DYNAMIC_TYPE_BIGINT); } #if defined(FREESCALE_LTC_TFM_RSA_4096_ENABLE) } else { res = wolfcrypt_mp_invmod(a, b, c); } #endif /* FREESCALE_LTC_TFM_RSA_4096_ENABLE */ return res; } /* d = a * b (mod c) */ int mp_mulmod(mp_int *a, mp_int *b, mp_int *c, mp_int *d) { int res = MP_OKAY; #if defined(FREESCALE_LTC_TFM_RSA_4096_ENABLE) int szA, szB, szC; szA = mp_unsigned_bin_size(a); szB = mp_unsigned_bin_size(b); szC = mp_unsigned_bin_size(c); if ((szA <= LTC_MAX_INT_BYTES) && (szB <= LTC_MAX_INT_BYTES) && (szC <= LTC_MAX_INT_BYTES)) { #endif /* FREESCALE_LTC_TFM_RSA_4096_ENABLE */ mp_int t; uint8_t *ptrA = (uint8_t *)XMALLOC(LTC_MAX_INT_BYTES, NULL, DYNAMIC_TYPE_BIGINT); uint8_t *ptrB = (uint8_t *)XMALLOC(LTC_MAX_INT_BYTES, NULL, DYNAMIC_TYPE_BIGINT); uint8_t *ptrC = (uint8_t *)XMALLOC(LTC_MAX_INT_BYTES, NULL, DYNAMIC_TYPE_BIGINT); uint8_t *ptrD = (uint8_t *)XMALLOC(LTC_MAX_INT_BYTES, NULL, DYNAMIC_TYPE_BIGINT); /* if A or B is negative, subtract abs(A) or abs(B) from modulus to get positive integer representation of the * same number */ res = mp_init(&t); #ifndef WOLFSSL_SP_MATH if (a->sign) { if (res == MP_OKAY) res = mp_add(a, c, &t); if (res == MP_OKAY) res = mp_copy(&t, a); } if (b->sign) { if (res == MP_OKAY) res = mp_add(b, c, &t); if (res == MP_OKAY) res = mp_copy(&t, b); } #endif if (res == MP_OKAY && ptrA && ptrB && ptrC && ptrD) { uint16_t sizeA, sizeB, sizeC, sizeD; res = ltc_get_lsb_bin_from_mp_int(ptrA, a, &sizeA); if (res == MP_OKAY) res = ltc_get_lsb_bin_from_mp_int(ptrB, b, &sizeB); if (res == MP_OKAY) res = ltc_get_lsb_bin_from_mp_int(ptrC, c, &sizeC); /* (A*B)mod C = ((A mod C) * (B mod C)) mod C */ if (res == MP_OKAY && LTC_PKHA_CompareBigNum(ptrA, sizeA, ptrC, sizeC) >= 0) { if (kStatus_Success != LTC_PKHA_ModRed(LTC_BASE, ptrA, sizeA, ptrC, sizeC, ptrA, &sizeA, kLTC_PKHA_IntegerArith)) { res = MP_VAL; } } if (res == MP_OKAY && (LTC_PKHA_CompareBigNum(ptrB, sizeB, ptrC, sizeC) >= 0)) { if (kStatus_Success != LTC_PKHA_ModRed(LTC_BASE, ptrB, sizeB, ptrC, sizeC, ptrB, &sizeB, kLTC_PKHA_IntegerArith)) { res = MP_VAL; } } if (res == MP_OKAY) { if (kStatus_Success != LTC_PKHA_ModMul(LTC_BASE, ptrA, sizeA, ptrB, sizeB, ptrC, sizeC, ptrD, &sizeD, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized)) { res = MP_VAL; } } if (res == MP_OKAY) { ltc_reverse_array(ptrD, sizeD); res = mp_read_unsigned_bin(d, ptrD, sizeD); } } else { res = MP_MEM; } if (ptrA) { XFREE(ptrA, NULL, DYNAMIC_TYPE_BIGINT); } if (ptrB) { XFREE(ptrB, NULL, DYNAMIC_TYPE_BIGINT); } if (ptrC) { XFREE(ptrC, NULL, DYNAMIC_TYPE_BIGINT); } if (ptrD) { XFREE(ptrD, NULL, DYNAMIC_TYPE_BIGINT); } #ifndef USE_FAST_MATH mp_clear(&t); #endif #if defined(FREESCALE_LTC_TFM_RSA_4096_ENABLE) } else { res = wolfcrypt_mp_mulmod(a, b, c, d); } #endif /* FREESCALE_LTC_TFM_RSA_4096_ENABLE */ return res; } /* Y = G^X mod P */ int mp_exptmod(mp_int *G, mp_int *X, mp_int *P, mp_int *Y) { int res = MP_OKAY; #if defined(FREESCALE_LTC_TFM_RSA_4096_ENABLE) int szA, szB, szC; mp_int tmp; /* if G cannot fit into LTC_PKHA, reduce it */ szA = mp_unsigned_bin_size(G); if (szA > LTC_MAX_INT_BYTES) { res = mp_init(&tmp); if (res != MP_OKAY) return res; if ((res = mp_mod(G, P, &tmp)) != MP_OKAY) { return res; } G = &tmp; szA = mp_unsigned_bin_size(G); } szB = mp_unsigned_bin_size(X); szC = mp_unsigned_bin_size(P); if ((szA <= LTC_MAX_INT_BYTES) && (szB <= LTC_MAX_INT_BYTES) && (szC <= LTC_MAX_INT_BYTES)) { #endif /* FREESCALE_LTC_TFM_RSA_4096_ENABLE */ mp_int t; uint16_t sizeG, sizeX, sizeP; uint8_t *ptrG = (uint8_t *)XMALLOC(LTC_MAX_INT_BYTES, 0, DYNAMIC_TYPE_BIGINT); uint8_t *ptrX = (uint8_t *)XMALLOC(LTC_MAX_INT_BYTES, 0, DYNAMIC_TYPE_BIGINT); uint8_t *ptrP = (uint8_t *)XMALLOC(LTC_MAX_INT_BYTES, 0, DYNAMIC_TYPE_BIGINT); /* if G is negative, add modulus to convert to positive number for LTC */ res = mp_init(&t); #ifndef WOLFSSL_SP_MATH if (G->sign) { if (res == MP_OKAY) res = mp_add(G, P, &t); if (res == MP_OKAY) res = mp_copy(&t, G); } #endif if (res == MP_OKAY && ptrG && ptrX && ptrP) { res = ltc_get_lsb_bin_from_mp_int(ptrG, G, &sizeG); if (res == MP_OKAY) res = ltc_get_lsb_bin_from_mp_int(ptrX, X, &sizeX); if (res == MP_OKAY) res = ltc_get_lsb_bin_from_mp_int(ptrP, P, &sizeP); /* if number if greater that modulo, we must first reduce due to LTC requirement on modular exponentiaton */ /* it needs number less than modulus. */ /* we can take advantage of modular arithmetic rule that: A^B mod C = ( (A mod C)^B ) mod C and so we do first (A mod N) : LTC does not give size requirement on A versus N, and then the modular exponentiation. */ /* if G >= P then */ if (res == MP_OKAY && LTC_PKHA_CompareBigNum(ptrG, sizeG, ptrP, sizeP) >= 0) { res = (int)LTC_PKHA_ModRed(LTC_BASE, ptrG, sizeG, ptrP, sizeP, ptrG, &sizeG, kLTC_PKHA_IntegerArith); if (res != kStatus_Success) { res = MP_VAL; } } if (res == MP_OKAY) { res = (int)LTC_PKHA_ModExp(LTC_BASE, ptrG, sizeG, ptrP, sizeP, ptrX, sizeX, ptrP, &sizeP, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); if (res != kStatus_Success) { res = MP_VAL; } else { ltc_reverse_array(ptrP, sizeP); res = mp_read_unsigned_bin(Y, ptrP, sizeP); } } } else { res = MP_MEM; } if (ptrG) { XFREE(ptrG, NULL, DYNAMIC_TYPE_BIGINT); } if (ptrX) { XFREE(ptrX, NULL, DYNAMIC_TYPE_BIGINT); } if (ptrP) { XFREE(ptrP, NULL, DYNAMIC_TYPE_BIGINT); } #ifndef USE_FAST_MATH mp_clear(&t); #endif #if defined(FREESCALE_LTC_TFM_RSA_4096_ENABLE) } else { res = wolfcrypt_mp_exptmod(G, X, P, Y); } #ifndef USE_FAST_MATH if (szA > LTC_MAX_INT_BYTES) mp_clear(&tmp); #endif #endif /* FREESCALE_LTC_TFM_RSA_4096_ENABLE */ return res; } #endif /* FREESCALE_LTC_TFM */ /* ECC */ #if defined(HAVE_ECC) && defined(FREESCALE_LTC_ECC) /* convert from mp_int to LTC integer, as array of bytes of size sz. * if mp_int has less bytes than sz, add zero bytes at most significant byte positions. * This is when for example modulus is 32 bytes (P-256 curve) * and mp_int has only 31 bytes, we add leading zeros * so that result array has 32 bytes, same as modulus (sz). */ static int ltc_get_from_mp_int(uint8_t *dst, mp_int *a, int sz) { int res; int szbin; int offset; /* check how many bytes are in the mp_int */ szbin = mp_unsigned_bin_size(a); /* compute offset from dst */ offset = sz - szbin; if (offset < 0) offset = 0; if (offset > sz) offset = sz; /* add leading zeroes */ if (offset) XMEMSET(dst, 0, offset); /* convert mp_int to array of bytes */ res = mp_to_unsigned_bin(a, dst + offset); if (res == MP_OKAY) { /* reverse array for LTC direct use */ ltc_reverse_array(dst, sz); } return res; } /* ECC specs in lsbyte at lowest address format for direct use by LTC PKHA driver functions */ #if defined(HAVE_ECC192) || defined(HAVE_ALL_CURVES) #define ECC192 #endif #if defined(HAVE_ECC224) || defined(HAVE_ALL_CURVES) #define ECC224 #endif #if !defined(NO_ECC256) || defined(HAVE_ALL_CURVES) #define ECC256 #endif #if defined(HAVE_ECC384) || defined(HAVE_ALL_CURVES) #define ECC384 #endif /* P-256 */ #ifdef ECC256 static const uint8_t ltc_ecc256_modulus[32] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0xFF}; static const uint8_t ltc_ecc256_r2modn[32] = { 0x03, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFB, 0xFF, 0xFF, 0xFF, 0xFE, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFD, 0xFF, 0xFF, 0xFF, 0x04, 0x00, 0x00, 0x00}; static const uint8_t ltc_ecc256_aCurveParam[32] = { 0xFC, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0xFF}; static const uint8_t ltc_ecc256_bCurveParam[32] = { 0x4B, 0x60, 0xD2, 0x27, 0x3E, 0x3C, 0xCE, 0x3B, 0xF6, 0xB0, 0x53, 0xCC, 0xB0, 0x06, 0x1D, 0x65, 0xBC, 0x86, 0x98, 0x76, 0x55, 0xBD, 0xEB, 0xB3, 0xE7, 0x93, 0x3A, 0xAA, 0xD8, 0x35, 0xC6, 0x5A}; #endif #ifdef ECC192 static const uint8_t ltc_ecc192_modulus[24] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFE, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF}; static const uint8_t ltc_ecc192_r2modn[24] = { 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}; static const uint8_t ltc_ecc192_aCurveParam[24] = { 0xFC, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFE, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF}; static const uint8_t ltc_ecc192_bCurveParam[24] = { 0xB1, 0xB9, 0x46, 0xC1, 0xEC, 0xDE, 0xB8, 0xFE, 0x49, 0x30, 0x24, 0x72, 0xAB, 0xE9, 0xA7, 0x0F, 0xE7, 0x80, 0x9C, 0xE5, 0x19, 0x05, 0x21, 0x64}; #endif #ifdef ECC224 static const uint8_t ltc_ecc224_modulus[28] = { 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF}; static const uint8_t ltc_ecc224_r2modn[28] = { 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFE, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00}; static const uint8_t ltc_ecc224_aCurveParam[28] = { 0xFE, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFE, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF}; static const uint8_t ltc_ecc224_bCurveParam[28] = { 0xB4, 0xFF, 0x55, 0x23, 0x43, 0x39, 0x0B, 0x27, 0xBA, 0xD8, 0xBF, 0xD7, 0xB7, 0xB0, 0x44, 0x50, 0x56, 0x32, 0x41, 0xF5, 0xAB, 0xB3, 0x04, 0x0C, 0x85, 0x0A, 0x05, 0xB4}; #endif #ifdef ECC384 static const uint8_t ltc_ecc384_modulus[48] = { 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xfe, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; static const uint8_t ltc_ecc384_r2modn[48] = { 0x01, 0x00, 0x00, 0x00, 0xfe, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xfe, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}; static const uint8_t ltc_ecc384_aCurveParam[48] = { 0xfc, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xfe, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; static const uint8_t ltc_ecc384_bCurveParam[48] = { 0xef, 0x2a, 0xec, 0xd3, 0xed, 0xc8, 0x85, 0x2a, 0x9d, 0xd1, 0x2e, 0x8a, 0x8d, 0x39, 0x56, 0xc6, 0x5a, 0x87, 0x13, 0x50, 0x8f, 0x08, 0x14, 0x03, 0x12, 0x41, 0x81, 0xfe, 0x6e, 0x9c, 0x1d, 0x18, 0x19, 0x2d, 0xf8, 0xe3, 0x6b, 0x05, 0x8e, 0x98, 0xe4, 0xe7, 0x3e, 0xe2, 0xa7, 0x2f, 0x31, 0xb3}; #endif static int ltc_get_ecc_specs(const uint8_t **modulus, const uint8_t **r2modn, const uint8_t **aCurveParam, const uint8_t **bCurveParam, int size) { switch(size) { case 32: *modulus = ltc_ecc256_modulus; *r2modn = ltc_ecc256_r2modn; *aCurveParam = ltc_ecc256_aCurveParam; *bCurveParam = ltc_ecc256_bCurveParam; break; #ifdef ECC224 case 28: *modulus = ltc_ecc224_modulus; *r2modn = ltc_ecc224_r2modn; *aCurveParam = ltc_ecc224_aCurveParam; *bCurveParam = ltc_ecc224_bCurveParam; break; #endif #ifdef ECC192 case 24: *modulus = ltc_ecc192_modulus; *r2modn = ltc_ecc192_r2modn; *aCurveParam = ltc_ecc192_aCurveParam; *bCurveParam = ltc_ecc192_bCurveParam; break; #endif #ifdef HAVE_ECC384 case 48: *modulus = ltc_ecc384_modulus; *r2modn = ltc_ecc384_r2modn; *aCurveParam = ltc_ecc384_aCurveParam; *bCurveParam = ltc_ecc384_bCurveParam; break; #endif default: return -1; } return 0; } /** Perform a point multiplication (timing resistant) k The scalar to multiply by G The base point R [out] Destination for kG modulus The modulus of the field the ECC curve is in map Boolean whether to map back to affine or not (1==map, 0 == leave in projective) return MP_OKAY on success */ int wc_ecc_mulmod_ex(mp_int *k, ecc_point *G, ecc_point *R, mp_int* a, mp_int *modulus, int map, void* heap) { ltc_pkha_ecc_point_t B; uint8_t size; int szModulus; int szkbin; bool point_of_infinity; status_t status; int res; (void)a; (void)heap; uint8_t Gxbin[LTC_MAX_ECC_BITS / 8]; uint8_t Gybin[LTC_MAX_ECC_BITS / 8]; uint8_t kbin[LTC_MAX_INT_BYTES]; const uint8_t *modbin; const uint8_t *aCurveParam; const uint8_t *bCurveParam; const uint8_t *r2modn; if (k == NULL || G == NULL || R == NULL || modulus == NULL) { return ECC_BAD_ARG_E; } szModulus = mp_unsigned_bin_size(modulus); szkbin = mp_unsigned_bin_size(k); res = ltc_get_from_mp_int(kbin, k, szkbin); if (res == MP_OKAY) res = ltc_get_from_mp_int(Gxbin, G->x, szModulus); if (res == MP_OKAY) res = ltc_get_from_mp_int(Gybin, G->y, szModulus); if (res != MP_OKAY) return res; size = szModulus; /* find LTC friendly parameters for the selected curve */ if (0 != ltc_get_ecc_specs(&modbin, &r2modn, &aCurveParam, &bCurveParam, size)) { return ECC_BAD_ARG_E; } B.X = &Gxbin[0]; B.Y = &Gybin[0]; status = LTC_PKHA_ECC_PointMul(LTC_BASE, &B, kbin, szkbin, modbin, r2modn, aCurveParam, bCurveParam, size, kLTC_PKHA_TimingEqualized, kLTC_PKHA_IntegerArith, &B, &point_of_infinity); if (status != kStatus_Success) { return MP_VAL; } ltc_reverse_array(Gxbin, size); ltc_reverse_array(Gybin, size); res = mp_read_unsigned_bin(R->x, Gxbin, size); if (res == MP_OKAY) { res = mp_read_unsigned_bin(R->y, Gybin, size); /* if k is negative, we compute the multiplication with abs(-k) * with result (x, y) and modify the result to (x, -y) */ #ifndef WOLFSSL_SP_MATH R->y->sign = k->sign; #endif } if (res == MP_OKAY) res = mp_set(R->z, 1); return res; } int wc_ecc_point_add(ecc_point *mG, ecc_point *mQ, ecc_point *mR, mp_int *m) { int res; ltc_pkha_ecc_point_t A, B; int size; status_t status; uint8_t Gxbin[LTC_MAX_ECC_BITS / 8]; uint8_t Gybin[LTC_MAX_ECC_BITS / 8]; uint8_t Qxbin[LTC_MAX_ECC_BITS / 8]; uint8_t Qybin[LTC_MAX_ECC_BITS / 8]; const uint8_t *modbin; const uint8_t *aCurveParam; const uint8_t *bCurveParam; const uint8_t *r2modn; size = mp_unsigned_bin_size(m); /* find LTC friendly parameters for the selected curve */ if (ltc_get_ecc_specs(&modbin, &r2modn, &aCurveParam, &bCurveParam, size) != 0) { res = ECC_BAD_ARG_E; } else { res = ltc_get_from_mp_int(Gxbin, mG->x, size); if (res == MP_OKAY) res = ltc_get_from_mp_int(Gybin, mG->y, size); if (res == MP_OKAY) res = ltc_get_from_mp_int(Qxbin, mQ->x, size); if (res == MP_OKAY) res = ltc_get_from_mp_int(Qybin, mQ->y, size); if (res != MP_OKAY) return res; A.X = Gxbin; A.Y = Gybin; B.X = Qxbin; B.Y = Qybin; status = LTC_PKHA_ECC_PointAdd(LTC_BASE, &A, &B, modbin, r2modn, aCurveParam, bCurveParam, size, kLTC_PKHA_IntegerArith, &A); if (status != kStatus_Success) { res = MP_VAL; } else { ltc_reverse_array(Gxbin, size); ltc_reverse_array(Gybin, size); res = mp_read_unsigned_bin(mR->x, Gxbin, size); if (res == MP_OKAY) res = mp_read_unsigned_bin(mR->y, Gybin, size); if (res == MP_OKAY) res = mp_set(mR->z, 1); } } return res; } #if defined(HAVE_ED25519) || defined(HAVE_CURVE25519) /* Weierstrass parameters of prime 2^255 - 19 */ static const uint8_t curve25519_modbin[32] = { 0xed, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x7f}; /* precomputed R2modN for the curve25519 */ static const uint8_t r2mod[32] = { 0xa4, 0x05, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}; /* invThree = ModInv(3,curve25519_modbin) in LSB first */ static const uint8_t invThree[32] = { 0x49, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55}; /* * * finds square root in finite field when modulus congruent to 5 modulo 8 * this is fixed to curve25519 modulus 2^255 - 19 which is congruent to 5 modulo 8 * * This function solves equation: res^2 = a mod (2^255 - 19) * p = prime p % 8 must be 5 v = ModularArithmetic.powmod(2*a, (p-5)/8, p) i = (2*a*v**2) % p r1 = 1*a*v*(i - 1) % p r2 = -1*a*v*(i - 1) % p puts "Gy=0x#{r2.to_s(16)}" */ status_t LTC_PKHA_Prime25519SquareRootMod(const uint8_t *A, size_t sizeA, uint8_t *res, size_t *szRes, int sign) { status_t status; const uint8_t curve25519_param[] = { 0xfd, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x0f}; uint8_t twoA[sizeof(curve25519_modbin)] = {0}; uint8_t V[sizeof(curve25519_modbin)] = {0}; uint8_t I[sizeof(curve25519_modbin)] = {0}; uint8_t VV[sizeof(curve25519_modbin)] = {0}; uint16_t szTwoA = 0; uint16_t szV = 0; uint16_t szVV = 0; uint16_t szI = 0; uint16_t szRes16 = 0; uint8_t one = 1; /* twoA = 2*A % p */ status = LTC_PKHA_ModAdd(LTC_BASE, A, sizeA, A, sizeA, curve25519_modbin, sizeof(curve25519_modbin), twoA, &szTwoA, kLTC_PKHA_IntegerArith); /* V = ModularArithmetic.powmod(twoA, (p-5)/8, p) */ if (status == kStatus_Success) { status = LTC_PKHA_ModExp(LTC_BASE, twoA, szTwoA, curve25519_modbin, sizeof(curve25519_modbin), curve25519_param, sizeof(curve25519_param), V, &szV, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); } /* VV = V*V % p */ if (status == kStatus_Success) { status = LTC_PKHA_ModMul(LTC_BASE, V, szV, V, szV, curve25519_modbin, sizeof(curve25519_modbin), VV, &szVV, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); } /* I = twoA * VV = 2*A*V*V % p */ if (status == kStatus_Success) { status = LTC_PKHA_ModMul(LTC_BASE, twoA, szTwoA, VV, szVV, curve25519_modbin, sizeof(curve25519_modbin), I, &szI, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); } /* I = I - 1 */ XMEMSET(VV, 0xff, sizeof(VV)); /* just temp for maximum integer - for non-modular subtract */ if (0 <= LTC_PKHA_CompareBigNum(I, szI, &one, sizeof(one))) { if (status == kStatus_Success) { status = LTC_PKHA_ModSub1(LTC_BASE, I, szI, &one, sizeof(one), VV, sizeof(VV), I, &szI); } } else { if (status == kStatus_Success) { status = LTC_PKHA_ModSub1(LTC_BASE, curve25519_modbin, sizeof(curve25519_modbin), &one, sizeof(one), VV, sizeof(VV), I, &szI); } } /* res = a*v mod p */ status = LTC_PKHA_ModMul(LTC_BASE, A, sizeA, V, szV, curve25519_modbin, sizeof(curve25519_modbin), res, &szRes16, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); /* res = res * (i-1) mod p */ if (status == kStatus_Success) { status = LTC_PKHA_ModMul(LTC_BASE, res, szRes16, I, szI, curve25519_modbin, sizeof(curve25519_modbin), res, &szRes16, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); } /* if X mod 2 != X_0 then we need the -X * * X mod 2 get from LSB bit0 */ if ((status == kStatus_Success) && ((bool)sign != (bool)(res[0] & 0x01u))) { status = LTC_PKHA_ModSub1(LTC_BASE, curve25519_modbin, sizeof(curve25519_modbin), res, szRes16, VV, sizeof(VV), res, &szRes16); /* -a = p - a */ } if (status == kStatus_Success) { *szRes = szRes16; } return status; } #endif /* HAVE_ED25519 || HAVE_CURVE25519 */ #ifdef HAVE_CURVE25519 /* for LTC we need Weierstrass format of curve25519 parameters * these two are base point X and Y. * in LSB first format (native for LTC) */ static const ECPoint ecBasePoint = { {0x5a, 0x24, 0xad, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0x2a}, {0xd9, 0xd3, 0xce, 0x7e, 0xa2, 0xc5, 0xe9, 0x29, 0xb2, 0x61, 0x7c, 0x6d, 0x7e, 0x4d, 0x3d, 0x92, 0x4c, 0xd1, 0x48, 0x77, 0x2c, 0xdd, 0x1e, 0xe0, 0xb4, 0x86, 0xa0, 0xb8, 0xa1, 0x19, 0xae, 0x20}, }; const ECPoint *wc_curve25519_GetBasePoint(void) { return &ecBasePoint; } static const uint8_t curve25519_aCurveParam[CURVE25519_KEYSIZE] = { 0x44, 0xa1, 0x14, 0x49, 0x98, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0x2a}; static const uint8_t curve_bCurveParam[CURVE25519_KEYSIZE] = { 0x64, 0xc8, 0x10, 0x77, 0x9c, 0x5e, 0x0b, 0x26, 0xb4, 0x97, 0xd0, 0x5e, 0x42, 0x7b, 0x09, 0xed, 0x25, 0xb4, 0x97, 0xd0, 0x5e, 0x42, 0x7b, 0x09, 0xed, 0x25, 0xb4, 0x97, 0xd0, 0x5e, 0x42, 0x7b}; /* transform a point on Montgomery curve to a point on Weierstrass curve */ status_t LTC_PKHA_Curve25519ToWeierstrass( const ltc_pkha_ecc_point_t *ltcPointIn,ltc_pkha_ecc_point_t *ltcPointOut) { /* offset X point (in Montgomery) so that it becomes Weierstrass */ const uint8_t offset[] = { 0x51, 0x24, 0xad, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0x2a}; uint16_t sizeRes = 0; status_t status; status = LTC_PKHA_ModAdd(LTC_BASE, ltcPointIn->X, CURVE25519_KEYSIZE, offset, sizeof(offset), curve25519_modbin, CURVE25519_KEYSIZE, ltcPointOut->X, &sizeRes, kLTC_PKHA_IntegerArith); if (status == kStatus_Success) { if (ltcPointOut->Y != ltcPointIn->Y) { XMEMCPY(ltcPointOut->Y, ltcPointIn->Y, CURVE25519_KEYSIZE); } } return status; } /* transform a point on Weierstrass curve to a point on Montgomery curve */ status_t LTC_PKHA_WeierstrassToCurve25519( const ltc_pkha_ecc_point_t *ltcPointIn, ltc_pkha_ecc_point_t *ltcPointOut) { status_t status; uint16_t resultSize = 0; const uint8_t three = 0x03; status = LTC_PKHA_ModMul(LTC_BASE, &three, sizeof(three), ltcPointIn->X, CURVE25519_KEYSIZE, curve25519_modbin, CURVE25519_KEYSIZE, ltcPointOut->X, &resultSize, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); if (status == kStatus_Success) { const uint8_t A[] = {0x06, 0x6d, 0x07}; if (LTC_PKHA_CompareBigNum(ltcPointOut->X, resultSize, A, sizeof(A))) { status = LTC_PKHA_ModSub1(LTC_BASE, ltcPointOut->X, resultSize, A, sizeof(A), curve25519_modbin, CURVE25519_KEYSIZE, ltcPointOut->X, &resultSize); } else { status = LTC_PKHA_ModSub2(LTC_BASE, ltcPointOut->X, resultSize, A, sizeof(A), curve25519_modbin, CURVE25519_KEYSIZE, ltcPointOut->X, &resultSize); } } if (status == kStatus_Success) { status = LTC_PKHA_ModMul(LTC_BASE, invThree, CURVE25519_KEYSIZE, ltcPointOut->X, resultSize, curve25519_modbin, CURVE25519_KEYSIZE, ltcPointOut->X, &resultSize, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); } if (status == kStatus_Success) { if (ltcPointOut->Y != ltcPointIn->Y) { XMEMCPY(ltcPointOut->Y, ltcPointIn->Y, CURVE25519_KEYSIZE); } } return status; } /* Y = square root (X^3 + 486662*X^2 + X) */ status_t LTC_PKHA_Curve25519ComputeY(ltc_pkha_ecc_point_t *ltcPoint) { uint8_t three = 3; const uint8_t A[] = {0x06, 0x6d, 0x07}; uint8_t U[CURVE25519_KEYSIZE] = {0}; uint8_t X2[CURVE25519_KEYSIZE] = {0}; uint16_t sizeU = 0; uint16_t sizeX2 = 0; size_t szRes = 0; status_t status; /* X^3 */ status = LTC_PKHA_ModExp(LTC_BASE, ltcPoint->X, CURVE25519_KEYSIZE, curve25519_modbin, CURVE25519_KEYSIZE, &three, 1, U, &sizeU, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); /* X^2 */ if (status == kStatus_Success) { status = LTC_PKHA_ModMul(LTC_BASE, ltcPoint->X, CURVE25519_KEYSIZE, ltcPoint->X, CURVE25519_KEYSIZE, curve25519_modbin, CURVE25519_KEYSIZE, X2, &sizeX2, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); } /* 486662*X^2 */ if (status == kStatus_Success) { status = LTC_PKHA_ModMul(LTC_BASE, A, sizeof(A), X2, sizeX2, curve25519_modbin, CURVE25519_KEYSIZE, X2, &sizeX2, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); } /* X^3 + 486662*X^2 */ if (status == kStatus_Success) { status = LTC_PKHA_ModAdd(LTC_BASE, U, sizeU, X2, sizeX2, curve25519_modbin, CURVE25519_KEYSIZE, U, &sizeU, kLTC_PKHA_IntegerArith); } /* U = X^3 + 486662*X^2 + X */ if (status == kStatus_Success) { status = LTC_PKHA_ModAdd(LTC_BASE, U, sizeU, ltcPoint->X, CURVE25519_KEYSIZE, curve25519_modbin, CURVE25519_KEYSIZE, U, &sizeU, kLTC_PKHA_IntegerArith); } /* Y = modular square root of U (U is Y^2) */ if (status == kStatus_Success) { status = LTC_PKHA_Prime25519SquareRootMod(U, sizeU, ltcPoint->Y, &szRes, 1); } return status; } /* Q = n*P */ /* if type is set, the input point p is in Montgomery curve coordinates, so there is a map to Weierstrass curve */ /* q output point is always in Montgomery curve coordinates */ int wc_curve25519(ECPoint *q, byte *n, const ECPoint *p, fsl_ltc_ecc_coordinate_system_t type) { status_t status; ltc_pkha_ecc_point_t ltcPoint; ltc_pkha_ecc_point_t ltcPointOut; ECPoint pIn = {{0}}; XMEMCPY(&pIn, p, sizeof(*p)); ltcPoint.X = &pIn.point[0]; ltcPoint.Y = &pIn.pointY[0]; /* if input point P is on Curve25519 Montgomery curve, transform it to Weierstrass equivalent */ if (type == kLTC_Curve25519) { LTC_PKHA_Curve25519ToWeierstrass(<cPoint, <cPoint); } ltcPointOut.X = &q->point[0]; ltcPointOut.Y = &q->pointY[0]; /* curve25519_modbin, r2mod, curve25519_aCurveParam, curve25519_bCurveParam * are Weierstrass equivalent with Curve25519 */ status = LTC_PKHA_ECC_PointMul(LTC_BASE, <cPoint, n, CURVE25519_KEYSIZE, curve25519_modbin, r2mod, curve25519_aCurveParam, curve25519_bCurveParam, CURVE25519_KEYSIZE, kLTC_PKHA_TimingEqualized, kLTC_PKHA_IntegerArith, <cPointOut, NULL); /* now need to map from Weierstrass form to Montgomery form */ if (status == kStatus_Success) { status = LTC_PKHA_WeierstrassToCurve25519(<cPointOut, <cPointOut); } return (status == kStatus_Success) ? 0 : IS_POINT_E; } #endif /* HAVE_CURVE25519 */ #ifdef HAVE_ED25519 /* a and d are Edwards curve parameters -1 and -121665/121666 prime is 2^255 - 19. * * https://en.wikipedia.org/wiki/Montgomery_curve#Equivalence_with_Edward_curves */ /* d parameter of ed25519 */ static const uint8_t d_coefEd25519[] = { 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}; /* Montgomery curve parameter A for a Montgomery curve equivalent with ed25519 */ static const uint8_t A_coefEd25519[] = { 0x06, 0x6d, 0x07, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}; /* Montgomery curve parameter B for a Montgomery curve equivalent with ed25519 */ static const uint8_t B_coefEd25519[] = { 0xe5, 0x92, 0xf8, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x7f}; /* these are pre-computed constants used in computations */ /* = 3*B */ static const uint8_t threeB_coefEd25519[] = { 0xd5, 0xb8, 0xe9, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x7f}; /* = -A */ static const uint8_t minus_A_coefEd25519[] = { 0xe7, 0x92, 0xf8, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x7f}; /* = 1/B */ static const uint8_t invB_coefEd25519[] = { 0xc4, 0xa1, 0x29, 0x7b, 0x8d, 0x2c, 0x85, 0x22, 0xd5, 0x89, 0xaf, 0xaf, 0x6c, 0xfd, 0xe3, 0xff, 0xd9, 0x85, 0x21, 0xa2, 0xe1, 0x2f, 0xce, 0x1c, 0x63, 0x00, 0x24, 0x75, 0xc4, 0x24, 0x7f, 0x6b}; /* = 1/(3*B) */ static const uint8_t A_mul_invThreeB_coefEd25519[] = { 0xb9, 0x3e, 0xe4, 0xad, 0xa1, 0x37, 0xa7, 0x93, 0x1c, 0xa4, 0x35, 0xe0, 0x0c, 0x57, 0xbd, 0xaa, 0x6e, 0x51, 0x94, 0x3e, 0x14, 0xe0, 0xcb, 0xec, 0xbd, 0xff, 0xe7, 0xb1, 0x27, 0x92, 0x00, 0x63}; /* Weierstrass curve parameter a for a Weierstrass curve equivalent with ed25519 */ static const uint8_t a_coefEd25519[] = { 0x2d, 0x17, 0xbc, 0xf8, 0x8e, 0xe1, 0x71, 0xac, 0xf7, 0x2a, 0xa5, 0x0c, 0x5d, 0xb6, 0xb8, 0x6b, 0xd6, 0x3d, 0x7b, 0x61, 0x0d, 0xe1, 0x97, 0x31, 0xe6, 0xbe, 0xb9, 0xa5, 0xd3, 0xac, 0x4e, 0x5d}; /* Weierstrass curve parameter b for a Weierstrass curve equivalent with ed25519 */ static const uint8_t b_coefEd25519[] = { 0xa4, 0xb2, 0x64, 0xf3, 0xc1, 0xeb, 0x04, 0x90, 0x32, 0xbc, 0x9f, 0x6b, 0x97, 0x31, 0x48, 0xf5, 0xd5, 0x80, 0x57, 0x10, 0x06, 0xdb, 0x0d, 0x55, 0xe0, 0xb3, 0xd0, 0xcf, 0x9b, 0xb2, 0x11, 0x1d}; /* Ed25519 basepoint B mapped to Weierstrass equivalent */ static uint8_t Wx_Ed25519[ED25519_KEY_SIZE] = { 0x35, 0xef, 0x5a, 0x02, 0x9b, 0xc8, 0x55, 0xca, 0x9a, 0x7c, 0x61, 0x0d, 0xdf, 0x3f, 0xc1, 0xa9, 0x18, 0x06, 0xc2, 0xf1, 0x02, 0x8f, 0x0b, 0xf0, 0x39, 0x03, 0x2c, 0xd0, 0x0f, 0xdd, 0x78, 0x2a}; static uint8_t Wy_Ed25519[ED25519_KEY_SIZE] = { 0x14, 0x1d, 0x2c, 0xf6, 0xf3, 0x30, 0x78, 0x9b, 0x65, 0x31, 0x71, 0x80, 0x61, 0xd0, 0x6f, 0xcf, 0x23, 0x83, 0x79, 0x63, 0xa5, 0x3b, 0x48, 0xbe, 0x2e, 0xa2, 0x1d, 0xc7, 0xa5, 0x44, 0xc6, 0x29}; static const ltc_pkha_ecc_point_t basepointEd25519 = { Wx_Ed25519, Wy_Ed25519, }; const ltc_pkha_ecc_point_t *LTC_PKHA_Ed25519_BasePoint(void) { return &basepointEd25519; } /* input point is on Weierstrass curve, typeOut determines the coordinates system of output point (either Weierstrass or Ed25519) */ status_t LTC_PKHA_Ed25519_PointMul(const ltc_pkha_ecc_point_t *ltcPointIn, const uint8_t *N, size_t sizeN, ltc_pkha_ecc_point_t *ltcPointOut, fsl_ltc_ecc_coordinate_system_t typeOut) { uint16_t szN = (uint16_t)sizeN; status_t status; /* input on W, output in W, W parameters of ECC curve are Ed25519 curve parameters mapped to Weierstrass curve */ status = LTC_PKHA_ECC_PointMul(LTC_BASE, ltcPointIn, N, szN, curve25519_modbin, r2mod, a_coefEd25519, b_coefEd25519, ED25519_KEY_SIZE, kLTC_PKHA_TimingEqualized, kLTC_PKHA_IntegerArith, ltcPointOut, NULL); /* Weierstrass coordinates to Ed25519 coordinates */ if ((status == kStatus_Success) && (typeOut == kLTC_Ed25519)) { status = LTC_PKHA_WeierstrassToEd25519(ltcPointOut, ltcPointOut); } return status; } status_t LTC_PKHA_Ed25519ToWeierstrass(const ltc_pkha_ecc_point_t *ltcPointIn, ltc_pkha_ecc_point_t *ltcPointOut) { status_t status; uint8_t Mx[ED25519_KEY_SIZE] = {0}; uint8_t My[ED25519_KEY_SIZE] = {0}; uint8_t temp[ED25519_KEY_SIZE] = {0}; uint8_t temp2[ED25519_KEY_SIZE] = {0}; const uint8_t max[32] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; const uint8_t *Ex; const uint8_t *Ey; uint8_t *Gx; uint8_t *Gy; uint16_t szMx = 0; uint16_t szGx = 0; uint16_t szMy = 0; uint16_t szGy = 0; uint16_t szTemp = 0; uint16_t szTemp2 = 0; uint8_t one = 1; Ex = ltcPointIn->X; Ey = ltcPointIn->Y; Gx = ltcPointOut->X; Gy = ltcPointOut->Y; /* # (Ex, Ey) on Ed (a_ed, d) to (x, y) on M (A,B) Mx = (1 + Ey) * ModularArithmetic.invert(1 - Ey, prime) % prime My = (1 + Ey) * ModularArithmetic.invert((1 - Ey)*Ex, prime) % prime */ /* Gx = ((Mx * ModularArithmetic.invert(B, prime)) + (A * ModularArithmetic.invert(3*B, prime))) % prime Gy = (My * ModularArithmetic.invert(B, prime)) % prime */ /* temp = 1 + Ey */ status = LTC_PKHA_ModAdd(LTC_BASE, Ey, ED25519_KEY_SIZE, &one, sizeof(one), curve25519_modbin, sizeof(curve25519_modbin), temp, &szTemp, kLTC_PKHA_IntegerArith); /* temp2 = 1 - Ey = 1 + (p - Ey) */ if (status == kStatus_Success) { status = LTC_PKHA_ModSub1(LTC_BASE, curve25519_modbin, sizeof(curve25519_modbin), Ey, ED25519_KEY_SIZE, max, sizeof(max), temp2, &szTemp2); } if (status == kStatus_Success) { status = LTC_PKHA_ModAdd(LTC_BASE, temp2, szTemp2, &one, sizeof(one), curve25519_modbin, sizeof(curve25519_modbin), temp2, &szTemp2, kLTC_PKHA_IntegerArith); } /* Mx = ModInv(temp2,prime) */ if (status == kStatus_Success) { status = LTC_PKHA_ModInv(LTC_BASE, temp2, szTemp2, curve25519_modbin, sizeof(curve25519_modbin), Mx, &szMx, kLTC_PKHA_IntegerArith); } /* Mx = Mx * temp */ if (status == kStatus_Success) { status = LTC_PKHA_ModMul(LTC_BASE, Mx, szMx, temp, szTemp, curve25519_modbin, ED25519_KEY_SIZE, Mx, &szMx, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); } /* My = temp2 * Ex */ if (status == kStatus_Success) { status = LTC_PKHA_ModMul(LTC_BASE, Ex, ED25519_KEY_SIZE, temp2, szTemp2, curve25519_modbin, ED25519_KEY_SIZE, My, &szMy, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); } /* My = ModInv(My, prime) */ if (status == kStatus_Success) { status = LTC_PKHA_ModInv(LTC_BASE, My, szMy, curve25519_modbin, sizeof(curve25519_modbin), My, &szMy, kLTC_PKHA_IntegerArith); } /* My = My * temp */ if (status == kStatus_Success) { status = LTC_PKHA_ModMul(LTC_BASE, My, szMy, temp, szTemp, curve25519_modbin, ED25519_KEY_SIZE, My, &szMy, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); } /* Gx = Mx * invB_coefEd25519 + A_mul_invThreeB_coefEd25519 */ if (status == kStatus_Success) { status = LTC_PKHA_ModMul(LTC_BASE, Mx, szMx, invB_coefEd25519, sizeof(invB_coefEd25519), curve25519_modbin, ED25519_KEY_SIZE, Gx, &szGx, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); } if (status == kStatus_Success) { status = LTC_PKHA_ModAdd(LTC_BASE, Gx, szGx, A_mul_invThreeB_coefEd25519, sizeof(A_mul_invThreeB_coefEd25519), curve25519_modbin, sizeof(curve25519_modbin), Gx, &szGx, kLTC_PKHA_IntegerArith); } /* Gy = My * invB_coefEd25519 */ if (status == kStatus_Success) { status = LTC_PKHA_ModMul(LTC_BASE, My, szMy, invB_coefEd25519, sizeof(invB_coefEd25519), curve25519_modbin, ED25519_KEY_SIZE, Gy, &szGy, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); } return status; } /* # (Gx, Gy) on W to (Ex, Ey) on E My = (B*Gy) % prime Mx = ((3*B*Gx-A)*ModularArithmetic.invert(3, prime)) % prime Ex = Mx*ModularArithmetic.invert(My, prime) % prime Ey = (Mx - 1)*ModularArithmetic.invert(Mx + 1, prime) % prime */ status_t LTC_PKHA_WeierstrassToEd25519(const ltc_pkha_ecc_point_t *ltcPointIn, ltc_pkha_ecc_point_t *ltcPointOut) { status_t status; uint8_t Mx[ED25519_KEY_SIZE] = {0}; uint8_t My[ED25519_KEY_SIZE] = {0}; uint8_t temp[ED25519_KEY_SIZE] = {0}; const uint8_t *Gx; const uint8_t *Gy; uint8_t *Ex; uint8_t *Ey; uint16_t szMx = 0; uint16_t szEx = 0; uint16_t szMy = 0; uint16_t szEy = 0; uint16_t szTemp = 0; uint8_t one = 1; Gx = ltcPointIn->X; Gy = ltcPointIn->Y; Ex = ltcPointOut->X; Ey = ltcPointOut->Y; /* My = (B*Gy) % prime */ status = LTC_PKHA_ModMul(LTC_BASE, B_coefEd25519, sizeof(B_coefEd25519), Gy, ED25519_KEY_SIZE, curve25519_modbin, ED25519_KEY_SIZE, My, &szMy, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); /* temp = 3*B*Gx mod p */ if (status == kStatus_Success) { status = LTC_PKHA_ModMul(LTC_BASE, threeB_coefEd25519, sizeof(threeB_coefEd25519), Gx, ED25519_KEY_SIZE, curve25519_modbin, ED25519_KEY_SIZE, temp, &szTemp, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); } /* temp = (temp - A) mod p */ if (status == kStatus_Success) { status = LTC_PKHA_ModAdd(LTC_BASE, temp, szTemp, minus_A_coefEd25519, sizeof(minus_A_coefEd25519), curve25519_modbin, sizeof(curve25519_modbin), temp, &szTemp, kLTC_PKHA_IntegerArith); } /* Mx = (temp/3) mod p */ if (status == kStatus_Success) { status = LTC_PKHA_ModMul(LTC_BASE, temp, szTemp, invThree, sizeof(invThree), curve25519_modbin, sizeof(curve25519_modbin), Mx, &szMx, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); } /* temp = 1/My mod p */ if (status == kStatus_Success) { status = LTC_PKHA_ModInv(LTC_BASE, My, szMy, curve25519_modbin, sizeof(curve25519_modbin), temp, &szTemp, kLTC_PKHA_IntegerArith); } /* Ex = Mx * temp mod p */ if (status == kStatus_Success) { status = LTC_PKHA_ModMul(LTC_BASE, temp, szTemp, Mx, szMx, curve25519_modbin, sizeof(curve25519_modbin), Ex, &szEx, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); } /* temp = Mx + 1 mod p */ if (status == kStatus_Success) { status = LTC_PKHA_ModAdd(LTC_BASE, Mx, szMx, &one, sizeof(one), curve25519_modbin, sizeof(curve25519_modbin), temp, &szTemp, kLTC_PKHA_IntegerArith); } /* temp = 1/temp mod p */ if (status == kStatus_Success) { status = LTC_PKHA_ModInv(LTC_BASE, temp, szTemp, curve25519_modbin, sizeof(curve25519_modbin), temp, &szTemp, kLTC_PKHA_IntegerArith); } /* Mx = (Mx - 1) mod p */ if (status == kStatus_Success) { if (LTC_PKHA_CompareBigNum(Mx, szMx, &one, sizeof(one)) >= 0) { status = LTC_PKHA_ModSub1(LTC_BASE, Mx, szMx, &one, sizeof(one), curve25519_modbin, sizeof(curve25519_modbin), Mx, &szMx); } else { /* Mx is zero, so it is modulus, thus we do modulus - 1 */ XMEMCPY(Mx, curve25519_modbin, sizeof(curve25519_modbin)); Mx[0]--; } } /* Ey = Mx * temp mod p */ if (status == kStatus_Success) { status = LTC_PKHA_ModMul(LTC_BASE, temp, szTemp, Mx, szMx, curve25519_modbin, sizeof(curve25519_modbin), Ey, &szEy, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); } return status; } status_t LTC_PKHA_Ed25519_PointDecompress(const uint8_t *pubkey, size_t pubKeySize, ltc_pkha_ecc_point_t *ltcPointOut) { status_t status; const uint8_t one = 1; /* pubkey contains the Y coordinate and a sign of X */ /* x^2 = ((y^2 - 1) / (d*y^2 +1)) mod p */ /* decode Y from pubkey */ XMEMCPY(ltcPointOut->Y, pubkey, pubKeySize); ltcPointOut->Y[pubKeySize - 1] &= ~0x80u; int sign = (int)(bool)(pubkey[pubKeySize - 1] & 0x80u); uint8_t U[ED25519_KEY_SIZE] = {0}; uint8_t V[ED25519_KEY_SIZE] = {0}; uint8_t *X = ltcPointOut->X; uint8_t *Y = ltcPointOut->Y; uint16_t szU = 0; uint16_t szV = 0; size_t szRes = 0; /* decode X from pubkey */ /* U = y * y mod p */ status = LTC_PKHA_ModMul(LTC_BASE, Y, ED25519_KEY_SIZE, Y, ED25519_KEY_SIZE, curve25519_modbin, ED25519_KEY_SIZE, U, &szU, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); XMEMCPY(V, U, szU); szV = szU; /* U = U - 1 = y^2 - 1 */ if (status == kStatus_Success) { if (LTC_PKHA_CompareBigNum(U, szU, &one, sizeof(one)) >= 0) { status = LTC_PKHA_ModSub1(LTC_BASE, U, szU, &one, sizeof(one), curve25519_modbin, sizeof(curve25519_modbin), U, &szU); } else { /* U is zero, so it is modulus, thus we do modulus - 1 */ XMEMCPY(U, curve25519_modbin, sizeof(curve25519_modbin)); U[0]--; } } /* V = d*y*y + 1 */ if (status == kStatus_Success) { status = LTC_PKHA_ModMul(LTC_BASE, V, szV, d_coefEd25519, ED25519_KEY_SIZE, curve25519_modbin, ED25519_KEY_SIZE, V, &szV, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); } if (status == kStatus_Success) { status = LTC_PKHA_ModAdd(LTC_BASE, V, szV, &one, sizeof(one), curve25519_modbin, sizeof(curve25519_modbin), V, &szV, kLTC_PKHA_IntegerArith); } /* U = U / V (mod p) */ if (status == kStatus_Success) { status = LTC_PKHA_ModInv(LTC_BASE, V, szV, curve25519_modbin, sizeof(curve25519_modbin), V, &szV, kLTC_PKHA_IntegerArith); } if (status == kStatus_Success) { status = LTC_PKHA_ModMul(LTC_BASE, V, szV, U, szU, curve25519_modbin, ED25519_KEY_SIZE, U, &szU, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); } /* get square root */ if (status == kStatus_Success) { status = LTC_PKHA_Prime25519SquareRootMod(U, szU, X, &szRes, sign); } return status; } /* LSByte first of Ed25519 parameter l = 2^252 + 27742317777372353535851937790883648493 */ static const uint8_t l_coefEdDSA[] = { 0xed, 0xd3, 0xf5, 0x5c, 0x1a, 0x63, 0x12, 0x58, 0xd6, 0x9c, 0xf7, 0xa2, 0xde, 0xf9, 0xde, 0x14, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10}; /* Input: s[0]+256*s[1]+...+256^63*s[63] = s Output: s[0]+256*s[1]+...+256^31*s[31] = s mod l where l = 2^252 + 27742317777372353535851937790883648493. Overwrites s in place. */ status_t LTC_PKHA_sc_reduce(uint8_t *a) { uint16_t szA = 0; return LTC_PKHA_ModRed(LTC_BASE, a, 64, l_coefEdDSA, sizeof(l_coefEdDSA), a, &szA, kLTC_PKHA_IntegerArith); } /* 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. */ status_t LTC_PKHA_sc_muladd(uint8_t *s, const uint8_t *a, const uint8_t *b, const uint8_t *c) { uint16_t szS = 0; uint16_t szB = 0; uint8_t tempB[32] = {0}; status_t status; /* Assume only b can be larger than modulus. It is called durind * wc_ed25519_sign_msg() where hram (=a) and nonce(=c) * have been reduced by LTC_PKHA_sc_reduce() * Thus reducing b only. */ status = LTC_PKHA_ModRed(LTC_BASE, b, 32, l_coefEdDSA, sizeof(l_coefEdDSA), tempB, &szB, kLTC_PKHA_IntegerArith); if (status == kStatus_Success) { status = LTC_PKHA_ModMul(LTC_BASE, a, 32, tempB, szB, l_coefEdDSA, sizeof(l_coefEdDSA), s, &szS, kLTC_PKHA_IntegerArith, kLTC_PKHA_NormalValue, kLTC_PKHA_NormalValue, kLTC_PKHA_TimingEqualized); } if (status == kStatus_Success) { status = LTC_PKHA_ModAdd(LTC_BASE, s, szS, c, 32, l_coefEdDSA, 32, s, &szS, kLTC_PKHA_IntegerArith); } return status; } /* r = a * A + b * B where A is public key point, B is basepoint where a = a[0]+256*a[1]+...+256^31 a[31]. and b = b[0]+256*b[1]+...+256^31 b[31]. B is the Ed25519 base point (x,4/5) with x positive. */ status_t LTC_PKHA_SignatureForVerify(uint8_t *rcheck, const unsigned char *a, const unsigned char *b, ed25519_key *key) { /* To verify a signature on a message M, first split the signature into two 32-octet halves. Decode the first half as a point R, and the second half as an integer s, in the range 0 <= s < q. If the decoding fails, the signature is invalid. */ /* Check the group equation 8s B = 8 R + 8k A. */ /* Uses a fast single-signature verification SB = R + H(R,A,M)A becomes SB - H(R,A,M)A saving decompression of R */ uint8_t X0[ED25519_PUB_KEY_SIZE] = {0}; uint8_t X1[ED25519_PUB_KEY_SIZE] = {0}; uint8_t Y0[ED25519_PUB_KEY_SIZE] = {0}; uint8_t Y1[ED25519_PUB_KEY_SIZE] = {0}; const uint8_t max[32] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; ltc_pkha_ecc_point_t ltc0; ltc_pkha_ecc_point_t ltc1; ltc_pkha_ecc_point_t pubKey; status_t status; /* The equality for the negative of a point P, in affine coordinates, is -P = -(x,y) = (x, -y) */ uint16_t szY = 32; ltc0.X = X0; ltc1.X = X1; ltc0.Y = Y0; ltc1.Y = Y1; pubKey.X = key->pointX; pubKey.Y = key->pointY; /* ltc0 = b*B */ status = LTC_PKHA_Ed25519_PointMul(LTC_PKHA_Ed25519_BasePoint(), b, ED25519_KEY_SIZE, <c0, kLTC_Weierstrass /* result in W */); /* ltc1 = a*A */ if (status == kStatus_Success) { status = LTC_PKHA_Ed25519ToWeierstrass(&pubKey, <c1); } if (status == kStatus_Success) { status = LTC_PKHA_Ed25519_PointMul(<c1, a, ED25519_KEY_SIZE, <c1, kLTC_Weierstrass /* result in W */); } /* R = b*B - a*A */ if (status == kStatus_Success) { status = LTC_PKHA_ModSub1(LTC_BASE, curve25519_modbin, sizeof(curve25519_modbin), ltc1.Y, szY, max, sizeof(max), ltc1.Y, &szY); } if (status == kStatus_Success) { status = LTC_PKHA_ECC_PointAdd(LTC_BASE, <c0, <c1, curve25519_modbin, r2mod, a_coefEd25519, b_coefEd25519, ED25519_KEY_SIZE, kLTC_PKHA_IntegerArith, <c0); } /* map to Ed25519 */ if (status == kStatus_Success) { status = LTC_PKHA_WeierstrassToEd25519(<c0, <c0); } if (((uint32_t)ltc0.X[0]) & 0x01u) { ltc0.Y[ED25519_KEY_SIZE - 1] |= 0x80u; } XMEMCPY(rcheck, ltc0.Y, ED25519_KEY_SIZE); return status; } status_t LTC_PKHA_Ed25519_Compress(const ltc_pkha_ecc_point_t *ltcPointIn, uint8_t *p) { /* compress */ /* get sign of X per https://tools.ietf.org/html/draft-josefsson-eddsa-ed25519-02 * To form the encoding of the point, copy the least significant bit of the x-coordinate to the most significant bit of the final octet */ XMEMCPY(p, ltcPointIn->Y, ED25519_KEY_SIZE); if (((uint32_t)ltcPointIn->X[0]) & 0x01u) { p[ED25519_KEY_SIZE - 1] |= 0x80u; } return kStatus_Success; } #endif /* HAVE_ED25519 */ #endif /* FREESCALE_LTC_ECC */ #undef ERROR_OUT #endif /* FREESCALE_LTC_TFM || FREESCALE_LTC_ECC */