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@@ -66,874 +66,874 @@ static uECC_RNG_Function g_rng_function = 0;
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void uECC_set_rng(uECC_RNG_Function rng_function)
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{
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- g_rng_function = rng_function;
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+ g_rng_function = rng_function;
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}
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uECC_RNG_Function uECC_get_rng(void)
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{
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- return g_rng_function;
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+ return g_rng_function;
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}
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int uECC_curve_private_key_size(uECC_Curve curve)
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{
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- return BITS_TO_BYTES(curve->num_n_bits);
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+ return BITS_TO_BYTES(curve->num_n_bits);
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}
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int uECC_curve_public_key_size(uECC_Curve curve)
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{
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- return 2 * curve->num_bytes;
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+ return 2 * curve->num_bytes;
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}
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void uECC_vli_clear(uECC_word_t *vli, wordcount_t num_words)
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{
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- wordcount_t i;
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- for (i = 0; i < num_words; ++i) {
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- vli[i] = 0;
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- }
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+ wordcount_t i;
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+ for (i = 0; i < num_words; ++i) {
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+ vli[i] = 0;
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+ }
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}
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uECC_word_t uECC_vli_isZero(const uECC_word_t *vli, wordcount_t num_words)
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{
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- uECC_word_t bits = 0;
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- wordcount_t i;
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- for (i = 0; i < num_words; ++i) {
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- bits |= vli[i];
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- }
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- return (bits == 0);
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+ uECC_word_t bits = 0;
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+ wordcount_t i;
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+ for (i = 0; i < num_words; ++i) {
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+ bits |= vli[i];
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+ }
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+ return (bits == 0);
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}
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uECC_word_t uECC_vli_testBit(const uECC_word_t *vli, bitcount_t bit)
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{
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- return (vli[bit >> uECC_WORD_BITS_SHIFT] &
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- ((uECC_word_t)1 << (bit & uECC_WORD_BITS_MASK)));
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+ return (vli[bit >> uECC_WORD_BITS_SHIFT] &
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+ ((uECC_word_t)1 << (bit & uECC_WORD_BITS_MASK)));
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}
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/* Counts the number of words in vli. */
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static wordcount_t vli_numDigits(const uECC_word_t *vli,
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- const wordcount_t max_words)
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+ const wordcount_t max_words)
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{
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- wordcount_t i;
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- /* Search from the end until we find a non-zero digit. We do it in reverse
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- * because we expect that most digits will be nonzero. */
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- for (i = max_words - 1; i >= 0 && vli[i] == 0; --i) {
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- }
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+ wordcount_t i;
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+ /* Search from the end until we find a non-zero digit. We do it in reverse
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+ * because we expect that most digits will be nonzero. */
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+ for (i = max_words - 1; i >= 0 && vli[i] == 0; --i) {
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+ }
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- return (i + 1);
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+ return (i + 1);
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}
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bitcount_t uECC_vli_numBits(const uECC_word_t *vli,
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- const wordcount_t max_words)
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+ const wordcount_t max_words)
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{
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- uECC_word_t i;
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- uECC_word_t digit;
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+ uECC_word_t i;
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+ uECC_word_t digit;
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- wordcount_t num_digits = vli_numDigits(vli, max_words);
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- if (num_digits == 0) {
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- return 0;
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- }
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+ wordcount_t num_digits = vli_numDigits(vli, max_words);
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+ if (num_digits == 0) {
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+ return 0;
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+ }
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- digit = vli[num_digits - 1];
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- for (i = 0; digit; ++i) {
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- digit >>= 1;
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- }
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+ digit = vli[num_digits - 1];
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+ for (i = 0; digit; ++i) {
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+ digit >>= 1;
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+ }
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- return (((bitcount_t)(num_digits - 1) << uECC_WORD_BITS_SHIFT) + i);
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+ return (((bitcount_t)(num_digits - 1) << uECC_WORD_BITS_SHIFT) + i);
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}
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void uECC_vli_set(uECC_word_t *dest, const uECC_word_t *src,
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- wordcount_t num_words)
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+ wordcount_t num_words)
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{
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- wordcount_t i;
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+ wordcount_t i;
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- for (i = 0; i < num_words; ++i) {
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- dest[i] = src[i];
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- }
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+ for (i = 0; i < num_words; ++i) {
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+ dest[i] = src[i];
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+ }
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}
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cmpresult_t uECC_vli_cmp_unsafe(const uECC_word_t *left,
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- const uECC_word_t *right,
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- wordcount_t num_words)
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+ const uECC_word_t *right,
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+ wordcount_t num_words)
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{
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- wordcount_t i;
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+ wordcount_t i;
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- for (i = num_words - 1; i >= 0; --i) {
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- if (left[i] > right[i]) {
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- return 1;
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- } else if (left[i] < right[i]) {
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- return -1;
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- }
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- }
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- return 0;
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+ for (i = num_words - 1; i >= 0; --i) {
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+ if (left[i] > right[i]) {
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+ return 1;
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+ } else if (left[i] < right[i]) {
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+ return -1;
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+ }
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+ }
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+ return 0;
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}
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uECC_word_t uECC_vli_equal(const uECC_word_t *left, const uECC_word_t *right,
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- wordcount_t num_words)
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+ wordcount_t num_words)
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{
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- uECC_word_t diff = 0;
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- wordcount_t i;
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+ uECC_word_t diff = 0;
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+ wordcount_t i;
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- for (i = num_words - 1; i >= 0; --i) {
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- diff |= (left[i] ^ right[i]);
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- }
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- return !(diff == 0);
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+ for (i = num_words - 1; i >= 0; --i) {
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+ diff |= (left[i] ^ right[i]);
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+ }
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+ return !(diff == 0);
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}
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uECC_word_t cond_set(uECC_word_t p_true, uECC_word_t p_false, unsigned int cond)
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{
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- return (p_true*(cond)) | (p_false*(!cond));
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+ return (p_true * (cond)) | (p_false * (!cond));
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}
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/* Computes result = left - right, returning borrow, in constant time.
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* Can modify in place. */
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uECC_word_t uECC_vli_sub(uECC_word_t *result, const uECC_word_t *left,
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- const uECC_word_t *right, wordcount_t num_words)
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+ const uECC_word_t *right, wordcount_t num_words)
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{
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- uECC_word_t borrow = 0;
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- wordcount_t i;
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- for (i = 0; i < num_words; ++i) {
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- uECC_word_t diff = left[i] - right[i] - borrow;
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- uECC_word_t val = (diff > left[i]);
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- borrow = cond_set(val, borrow, (diff != left[i]));
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+ uECC_word_t borrow = 0;
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+ wordcount_t i;
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+ for (i = 0; i < num_words; ++i) {
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+ uECC_word_t diff = left[i] - right[i] - borrow;
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+ uECC_word_t val = (diff > left[i]);
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+ borrow = cond_set(val, borrow, (diff != left[i]));
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- result[i] = diff;
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- }
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- return borrow;
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+ result[i] = diff;
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+ }
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+ return borrow;
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}
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/* Computes result = left + right, returning carry, in constant time.
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* Can modify in place. */
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static uECC_word_t uECC_vli_add(uECC_word_t *result, const uECC_word_t *left,
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- const uECC_word_t *right, wordcount_t num_words)
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+ const uECC_word_t *right, wordcount_t num_words)
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{
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- uECC_word_t carry = 0;
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- wordcount_t i;
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- for (i = 0; i < num_words; ++i) {
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- uECC_word_t sum = left[i] + right[i] + carry;
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- uECC_word_t val = (sum < left[i]);
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- carry = cond_set(val, carry, (sum != left[i]));
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- result[i] = sum;
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- }
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- return carry;
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+ uECC_word_t carry = 0;
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+ wordcount_t i;
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+ for (i = 0; i < num_words; ++i) {
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+ uECC_word_t sum = left[i] + right[i] + carry;
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+ uECC_word_t val = (sum < left[i]);
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+ carry = cond_set(val, carry, (sum != left[i]));
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+ result[i] = sum;
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+ }
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+ return carry;
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}
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cmpresult_t uECC_vli_cmp(const uECC_word_t *left, const uECC_word_t *right,
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- wordcount_t num_words)
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+ wordcount_t num_words)
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{
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- uECC_word_t tmp[NUM_ECC_WORDS];
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- uECC_word_t neg = !!uECC_vli_sub(tmp, left, right, num_words);
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- uECC_word_t equal = uECC_vli_isZero(tmp, num_words);
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- return (!equal - 2 * neg);
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+ uECC_word_t tmp[NUM_ECC_WORDS];
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+ uECC_word_t neg = !!uECC_vli_sub(tmp, left, right, num_words);
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+ uECC_word_t equal = uECC_vli_isZero(tmp, num_words);
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+ return (!equal - 2 * neg);
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}
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/* Computes vli = vli >> 1. */
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static void uECC_vli_rshift1(uECC_word_t *vli, wordcount_t num_words)
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{
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- uECC_word_t *end = vli;
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- uECC_word_t carry = 0;
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+ uECC_word_t *end = vli;
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+ uECC_word_t carry = 0;
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- vli += num_words;
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- while (vli-- > end) {
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- uECC_word_t temp = *vli;
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- *vli = (temp >> 1) | carry;
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- carry = temp << (uECC_WORD_BITS - 1);
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- }
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+ vli += num_words;
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+ while (vli-- > end) {
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+ uECC_word_t temp = *vli;
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+ *vli = (temp >> 1) | carry;
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+ carry = temp << (uECC_WORD_BITS - 1);
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+ }
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}
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static void muladd(uECC_word_t a, uECC_word_t b, uECC_word_t *r0,
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- uECC_word_t *r1, uECC_word_t *r2)
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+ uECC_word_t *r1, uECC_word_t *r2)
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{
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- uECC_dword_t p = (uECC_dword_t)a * b;
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- uECC_dword_t r01 = ((uECC_dword_t)(*r1) << uECC_WORD_BITS) | *r0;
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- r01 += p;
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- *r2 += (r01 < p);
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- *r1 = r01 >> uECC_WORD_BITS;
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- *r0 = (uECC_word_t)r01;
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+ uECC_dword_t p = (uECC_dword_t)a * b;
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+ uECC_dword_t r01 = ((uECC_dword_t)(*r1) << uECC_WORD_BITS) | *r0;
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+ r01 += p;
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+ *r2 += (r01 < p);
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+ *r1 = r01 >> uECC_WORD_BITS;
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+ *r0 = (uECC_word_t)r01;
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}
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/* Computes result = left * right. Result must be 2 * num_words long. */
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static void uECC_vli_mult(uECC_word_t *result, const uECC_word_t *left,
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- const uECC_word_t *right, wordcount_t num_words)
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+ const uECC_word_t *right, wordcount_t num_words)
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{
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- uECC_word_t r0 = 0;
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- uECC_word_t r1 = 0;
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- uECC_word_t r2 = 0;
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- wordcount_t i, k;
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+ uECC_word_t r0 = 0;
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+ uECC_word_t r1 = 0;
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+ uECC_word_t r2 = 0;
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+ wordcount_t i, k;
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- /* Compute each digit of result in sequence, maintaining the carries. */
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- for (k = 0; k < num_words; ++k) {
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+ /* Compute each digit of result in sequence, maintaining the carries. */
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+ for (k = 0; k < num_words; ++k) {
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- for (i = 0; i <= k; ++i) {
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- muladd(left[i], right[k - i], &r0, &r1, &r2);
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- }
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+ for (i = 0; i <= k; ++i) {
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+ muladd(left[i], right[k - i], &r0, &r1, &r2);
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+ }
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- result[k] = r0;
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- r0 = r1;
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- r1 = r2;
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- r2 = 0;
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- }
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+ result[k] = r0;
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+ r0 = r1;
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+ r1 = r2;
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+ r2 = 0;
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+ }
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- for (k = num_words; k < num_words * 2 - 1; ++k) {
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+ for (k = num_words; k < num_words * 2 - 1; ++k) {
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- for (i = (k + 1) - num_words; i < num_words; ++i) {
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- muladd(left[i], right[k - i], &r0, &r1, &r2);
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- }
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- result[k] = r0;
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- r0 = r1;
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- r1 = r2;
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- r2 = 0;
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- }
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- result[num_words * 2 - 1] = r0;
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+ for (i = (k + 1) - num_words; i < num_words; ++i) {
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+ muladd(left[i], right[k - i], &r0, &r1, &r2);
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+ }
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+ result[k] = r0;
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+ r0 = r1;
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+ r1 = r2;
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+ r2 = 0;
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+ }
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+ result[num_words * 2 - 1] = r0;
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}
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void uECC_vli_modAdd(uECC_word_t *result, const uECC_word_t *left,
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- const uECC_word_t *right, const uECC_word_t *mod,
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- wordcount_t num_words)
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+ const uECC_word_t *right, const uECC_word_t *mod,
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+ wordcount_t num_words)
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{
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- uECC_word_t carry = uECC_vli_add(result, left, right, num_words);
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- if (carry || uECC_vli_cmp_unsafe(mod, result, num_words) != 1) {
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- /* result > mod (result = mod + remainder), so subtract mod to get
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- * remainder. */
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- uECC_vli_sub(result, result, mod, num_words);
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- }
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+ uECC_word_t carry = uECC_vli_add(result, left, right, num_words);
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+ if (carry || uECC_vli_cmp_unsafe(mod, result, num_words) != 1) {
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+ /* result > mod (result = mod + remainder), so subtract mod to get
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+ * remainder. */
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+ uECC_vli_sub(result, result, mod, num_words);
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+ }
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}
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void uECC_vli_modSub(uECC_word_t *result, const uECC_word_t *left,
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- const uECC_word_t *right, const uECC_word_t *mod,
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- wordcount_t num_words)
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+ const uECC_word_t *right, const uECC_word_t *mod,
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+ wordcount_t num_words)
|
|
|
{
|
|
|
- uECC_word_t l_borrow = uECC_vli_sub(result, left, right, num_words);
|
|
|
- if (l_borrow) {
|
|
|
- /* In this case, result == -diff == (max int) - diff. Since -x % d == d - x,
|
|
|
- * we can get the correct result from result + mod (with overflow). */
|
|
|
- uECC_vli_add(result, result, mod, num_words);
|
|
|
- }
|
|
|
+ uECC_word_t l_borrow = uECC_vli_sub(result, left, right, num_words);
|
|
|
+ if (l_borrow) {
|
|
|
+ /* In this case, result == -diff == (max int) - diff. Since -x % d == d - x,
|
|
|
+ * we can get the correct result from result + mod (with overflow). */
|
|
|
+ uECC_vli_add(result, result, mod, num_words);
|
|
|
+ }
|
|
|
}
|
|
|
|
|
|
/* Computes result = product % mod, where product is 2N words long. */
|
|
|
/* Currently only designed to work for curve_p or curve_n. */
|
|
|
void uECC_vli_mmod(uECC_word_t *result, uECC_word_t *product,
|
|
|
- const uECC_word_t *mod, wordcount_t num_words)
|
|
|
-{
|
|
|
- uECC_word_t mod_multiple[2 * NUM_ECC_WORDS];
|
|
|
- uECC_word_t tmp[2 * NUM_ECC_WORDS];
|
|
|
- uECC_word_t *v[2] = {tmp, product};
|
|
|
- uECC_word_t index;
|
|
|
-
|
|
|
- /* Shift mod so its highest set bit is at the maximum position. */
|
|
|
- bitcount_t shift = (num_words * 2 * uECC_WORD_BITS) -
|
|
|
- uECC_vli_numBits(mod, num_words);
|
|
|
- wordcount_t word_shift = shift / uECC_WORD_BITS;
|
|
|
- wordcount_t bit_shift = shift % uECC_WORD_BITS;
|
|
|
- uECC_word_t carry = 0;
|
|
|
- uECC_vli_clear(mod_multiple, word_shift);
|
|
|
- if (bit_shift > 0) {
|
|
|
- for(index = 0; index < (uECC_word_t)num_words; ++index) {
|
|
|
- mod_multiple[word_shift + index] = (mod[index] << bit_shift) | carry;
|
|
|
- carry = mod[index] >> (uECC_WORD_BITS - bit_shift);
|
|
|
- }
|
|
|
- } else {
|
|
|
- uECC_vli_set(mod_multiple + word_shift, mod, num_words);
|
|
|
- }
|
|
|
-
|
|
|
- for (index = 1; shift >= 0; --shift) {
|
|
|
- uECC_word_t borrow = 0;
|
|
|
- wordcount_t i;
|
|
|
- for (i = 0; i < num_words * 2; ++i) {
|
|
|
- uECC_word_t diff = v[index][i] - mod_multiple[i] - borrow;
|
|
|
- if (diff != v[index][i]) {
|
|
|
- borrow = (diff > v[index][i]);
|
|
|
- }
|
|
|
- v[1 - index][i] = diff;
|
|
|
- }
|
|
|
- /* Swap the index if there was no borrow */
|
|
|
- index = !(index ^ borrow);
|
|
|
- uECC_vli_rshift1(mod_multiple, num_words);
|
|
|
- mod_multiple[num_words - 1] |= mod_multiple[num_words] <<
|
|
|
- (uECC_WORD_BITS - 1);
|
|
|
- uECC_vli_rshift1(mod_multiple + num_words, num_words);
|
|
|
- }
|
|
|
- uECC_vli_set(result, v[index], num_words);
|
|
|
+ const uECC_word_t *mod, wordcount_t num_words)
|
|
|
+{
|
|
|
+ uECC_word_t mod_multiple[2 * NUM_ECC_WORDS];
|
|
|
+ uECC_word_t tmp[2 * NUM_ECC_WORDS];
|
|
|
+ uECC_word_t *v[2] = {tmp, product};
|
|
|
+ uECC_word_t index;
|
|
|
+
|
|
|
+ /* Shift mod so its highest set bit is at the maximum position. */
|
|
|
+ bitcount_t shift = (num_words * 2 * uECC_WORD_BITS) -
|
|
|
+ uECC_vli_numBits(mod, num_words);
|
|
|
+ wordcount_t word_shift = shift / uECC_WORD_BITS;
|
|
|
+ wordcount_t bit_shift = shift % uECC_WORD_BITS;
|
|
|
+ uECC_word_t carry = 0;
|
|
|
+ uECC_vli_clear(mod_multiple, word_shift);
|
|
|
+ if (bit_shift > 0) {
|
|
|
+ for (index = 0; index < (uECC_word_t)num_words; ++index) {
|
|
|
+ mod_multiple[word_shift + index] = (mod[index] << bit_shift) | carry;
|
|
|
+ carry = mod[index] >> (uECC_WORD_BITS - bit_shift);
|
|
|
+ }
|
|
|
+ } else {
|
|
|
+ uECC_vli_set(mod_multiple + word_shift, mod, num_words);
|
|
|
+ }
|
|
|
+
|
|
|
+ for (index = 1; shift >= 0; --shift) {
|
|
|
+ uECC_word_t borrow = 0;
|
|
|
+ wordcount_t i;
|
|
|
+ for (i = 0; i < num_words * 2; ++i) {
|
|
|
+ uECC_word_t diff = v[index][i] - mod_multiple[i] - borrow;
|
|
|
+ if (diff != v[index][i]) {
|
|
|
+ borrow = (diff > v[index][i]);
|
|
|
+ }
|
|
|
+ v[1 - index][i] = diff;
|
|
|
+ }
|
|
|
+ /* Swap the index if there was no borrow */
|
|
|
+ index = !(index ^ borrow);
|
|
|
+ uECC_vli_rshift1(mod_multiple, num_words);
|
|
|
+ mod_multiple[num_words - 1] |= mod_multiple[num_words] <<
|
|
|
+ (uECC_WORD_BITS - 1);
|
|
|
+ uECC_vli_rshift1(mod_multiple + num_words, num_words);
|
|
|
+ }
|
|
|
+ uECC_vli_set(result, v[index], num_words);
|
|
|
}
|
|
|
|
|
|
void uECC_vli_modMult(uECC_word_t *result, const uECC_word_t *left,
|
|
|
- const uECC_word_t *right, const uECC_word_t *mod,
|
|
|
- wordcount_t num_words)
|
|
|
+ const uECC_word_t *right, const uECC_word_t *mod,
|
|
|
+ wordcount_t num_words)
|
|
|
{
|
|
|
- uECC_word_t product[2 * NUM_ECC_WORDS];
|
|
|
- uECC_vli_mult(product, left, right, num_words);
|
|
|
- uECC_vli_mmod(result, product, mod, num_words);
|
|
|
+ uECC_word_t product[2 * NUM_ECC_WORDS];
|
|
|
+ uECC_vli_mult(product, left, right, num_words);
|
|
|
+ uECC_vli_mmod(result, product, mod, num_words);
|
|
|
}
|
|
|
|
|
|
void uECC_vli_modMult_fast(uECC_word_t *result, const uECC_word_t *left,
|
|
|
- const uECC_word_t *right, uECC_Curve curve)
|
|
|
+ const uECC_word_t *right, uECC_Curve curve)
|
|
|
{
|
|
|
- uECC_word_t product[2 * NUM_ECC_WORDS];
|
|
|
- uECC_vli_mult(product, left, right, curve->num_words);
|
|
|
+ uECC_word_t product[2 * NUM_ECC_WORDS];
|
|
|
+ uECC_vli_mult(product, left, right, curve->num_words);
|
|
|
|
|
|
- curve->mmod_fast(result, product);
|
|
|
+ curve->mmod_fast(result, product);
|
|
|
}
|
|
|
|
|
|
static void uECC_vli_modSquare_fast(uECC_word_t *result,
|
|
|
- const uECC_word_t *left,
|
|
|
- uECC_Curve curve)
|
|
|
+ const uECC_word_t *left,
|
|
|
+ uECC_Curve curve)
|
|
|
{
|
|
|
- uECC_vli_modMult_fast(result, left, left, curve);
|
|
|
+ uECC_vli_modMult_fast(result, left, left, curve);
|
|
|
}
|
|
|
|
|
|
|
|
|
#define EVEN(vli) (!(vli[0] & 1))
|
|
|
|
|
|
static void vli_modInv_update(uECC_word_t *uv,
|
|
|
- const uECC_word_t *mod,
|
|
|
- wordcount_t num_words)
|
|
|
+ const uECC_word_t *mod,
|
|
|
+ wordcount_t num_words)
|
|
|
{
|
|
|
|
|
|
- uECC_word_t carry = 0;
|
|
|
+ uECC_word_t carry = 0;
|
|
|
|
|
|
- if (!EVEN(uv)) {
|
|
|
- carry = uECC_vli_add(uv, uv, mod, num_words);
|
|
|
- }
|
|
|
- uECC_vli_rshift1(uv, num_words);
|
|
|
- if (carry) {
|
|
|
- uv[num_words - 1] |= HIGH_BIT_SET;
|
|
|
- }
|
|
|
+ if (!EVEN(uv)) {
|
|
|
+ carry = uECC_vli_add(uv, uv, mod, num_words);
|
|
|
+ }
|
|
|
+ uECC_vli_rshift1(uv, num_words);
|
|
|
+ if (carry) {
|
|
|
+ uv[num_words - 1] |= HIGH_BIT_SET;
|
|
|
+ }
|
|
|
}
|
|
|
|
|
|
void uECC_vli_modInv(uECC_word_t *result, const uECC_word_t *input,
|
|
|
- const uECC_word_t *mod, wordcount_t num_words)
|
|
|
-{
|
|
|
- uECC_word_t a[NUM_ECC_WORDS], b[NUM_ECC_WORDS];
|
|
|
- uECC_word_t u[NUM_ECC_WORDS], v[NUM_ECC_WORDS];
|
|
|
- cmpresult_t cmpResult;
|
|
|
-
|
|
|
- if (uECC_vli_isZero(input, num_words)) {
|
|
|
- uECC_vli_clear(result, num_words);
|
|
|
- return;
|
|
|
- }
|
|
|
-
|
|
|
- uECC_vli_set(a, input, num_words);
|
|
|
- uECC_vli_set(b, mod, num_words);
|
|
|
- uECC_vli_clear(u, num_words);
|
|
|
- u[0] = 1;
|
|
|
- uECC_vli_clear(v, num_words);
|
|
|
- while ((cmpResult = uECC_vli_cmp_unsafe(a, b, num_words)) != 0) {
|
|
|
- if (EVEN(a)) {
|
|
|
- uECC_vli_rshift1(a, num_words);
|
|
|
- vli_modInv_update(u, mod, num_words);
|
|
|
- } else if (EVEN(b)) {
|
|
|
- uECC_vli_rshift1(b, num_words);
|
|
|
- vli_modInv_update(v, mod, num_words);
|
|
|
- } else if (cmpResult > 0) {
|
|
|
- uECC_vli_sub(a, a, b, num_words);
|
|
|
- uECC_vli_rshift1(a, num_words);
|
|
|
- if (uECC_vli_cmp_unsafe(u, v, num_words) < 0) {
|
|
|
- uECC_vli_add(u, u, mod, num_words);
|
|
|
- }
|
|
|
- uECC_vli_sub(u, u, v, num_words);
|
|
|
- vli_modInv_update(u, mod, num_words);
|
|
|
- } else {
|
|
|
- uECC_vli_sub(b, b, a, num_words);
|
|
|
- uECC_vli_rshift1(b, num_words);
|
|
|
- if (uECC_vli_cmp_unsafe(v, u, num_words) < 0) {
|
|
|
- uECC_vli_add(v, v, mod, num_words);
|
|
|
- }
|
|
|
- uECC_vli_sub(v, v, u, num_words);
|
|
|
- vli_modInv_update(v, mod, num_words);
|
|
|
- }
|
|
|
- }
|
|
|
- uECC_vli_set(result, u, num_words);
|
|
|
+ const uECC_word_t *mod, wordcount_t num_words)
|
|
|
+{
|
|
|
+ uECC_word_t a[NUM_ECC_WORDS], b[NUM_ECC_WORDS];
|
|
|
+ uECC_word_t u[NUM_ECC_WORDS], v[NUM_ECC_WORDS];
|
|
|
+ cmpresult_t cmpResult;
|
|
|
+
|
|
|
+ if (uECC_vli_isZero(input, num_words)) {
|
|
|
+ uECC_vli_clear(result, num_words);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+
|
|
|
+ uECC_vli_set(a, input, num_words);
|
|
|
+ uECC_vli_set(b, mod, num_words);
|
|
|
+ uECC_vli_clear(u, num_words);
|
|
|
+ u[0] = 1;
|
|
|
+ uECC_vli_clear(v, num_words);
|
|
|
+ while ((cmpResult = uECC_vli_cmp_unsafe(a, b, num_words)) != 0) {
|
|
|
+ if (EVEN(a)) {
|
|
|
+ uECC_vli_rshift1(a, num_words);
|
|
|
+ vli_modInv_update(u, mod, num_words);
|
|
|
+ } else if (EVEN(b)) {
|
|
|
+ uECC_vli_rshift1(b, num_words);
|
|
|
+ vli_modInv_update(v, mod, num_words);
|
|
|
+ } else if (cmpResult > 0) {
|
|
|
+ uECC_vli_sub(a, a, b, num_words);
|
|
|
+ uECC_vli_rshift1(a, num_words);
|
|
|
+ if (uECC_vli_cmp_unsafe(u, v, num_words) < 0) {
|
|
|
+ uECC_vli_add(u, u, mod, num_words);
|
|
|
+ }
|
|
|
+ uECC_vli_sub(u, u, v, num_words);
|
|
|
+ vli_modInv_update(u, mod, num_words);
|
|
|
+ } else {
|
|
|
+ uECC_vli_sub(b, b, a, num_words);
|
|
|
+ uECC_vli_rshift1(b, num_words);
|
|
|
+ if (uECC_vli_cmp_unsafe(v, u, num_words) < 0) {
|
|
|
+ uECC_vli_add(v, v, mod, num_words);
|
|
|
+ }
|
|
|
+ uECC_vli_sub(v, v, u, num_words);
|
|
|
+ vli_modInv_update(v, mod, num_words);
|
|
|
+ }
|
|
|
+ }
|
|
|
+ uECC_vli_set(result, u, num_words);
|
|
|
}
|
|
|
|
|
|
/* ------ Point operations ------ */
|
|
|
|
|
|
-void double_jacobian_default(uECC_word_t * X1, uECC_word_t * Y1,
|
|
|
- uECC_word_t * Z1, uECC_Curve curve)
|
|
|
-{
|
|
|
- /* t1 = X, t2 = Y, t3 = Z */
|
|
|
- uECC_word_t t4[NUM_ECC_WORDS];
|
|
|
- uECC_word_t t5[NUM_ECC_WORDS];
|
|
|
- wordcount_t num_words = curve->num_words;
|
|
|
-
|
|
|
- if (uECC_vli_isZero(Z1, num_words)) {
|
|
|
- return;
|
|
|
- }
|
|
|
-
|
|
|
- uECC_vli_modSquare_fast(t4, Y1, curve); /* t4 = y1^2 */
|
|
|
- uECC_vli_modMult_fast(t5, X1, t4, curve); /* t5 = x1*y1^2 = A */
|
|
|
- uECC_vli_modSquare_fast(t4, t4, curve); /* t4 = y1^4 */
|
|
|
- uECC_vli_modMult_fast(Y1, Y1, Z1, curve); /* t2 = y1*z1 = z3 */
|
|
|
- uECC_vli_modSquare_fast(Z1, Z1, curve); /* t3 = z1^2 */
|
|
|
-
|
|
|
- uECC_vli_modAdd(X1, X1, Z1, curve->p, num_words); /* t1 = x1 + z1^2 */
|
|
|
- uECC_vli_modAdd(Z1, Z1, Z1, curve->p, num_words); /* t3 = 2*z1^2 */
|
|
|
- uECC_vli_modSub(Z1, X1, Z1, curve->p, num_words); /* t3 = x1 - z1^2 */
|
|
|
- uECC_vli_modMult_fast(X1, X1, Z1, curve); /* t1 = x1^2 - z1^4 */
|
|
|
-
|
|
|
- uECC_vli_modAdd(Z1, X1, X1, curve->p, num_words); /* t3 = 2*(x1^2 - z1^4) */
|
|
|
- uECC_vli_modAdd(X1, X1, Z1, curve->p, num_words); /* t1 = 3*(x1^2 - z1^4) */
|
|
|
- if (uECC_vli_testBit(X1, 0)) {
|
|
|
- uECC_word_t l_carry = uECC_vli_add(X1, X1, curve->p, num_words);
|
|
|
- uECC_vli_rshift1(X1, num_words);
|
|
|
- X1[num_words - 1] |= l_carry << (uECC_WORD_BITS - 1);
|
|
|
- } else {
|
|
|
- uECC_vli_rshift1(X1, num_words);
|
|
|
- }
|
|
|
-
|
|
|
- /* t1 = 3/2*(x1^2 - z1^4) = B */
|
|
|
- uECC_vli_modSquare_fast(Z1, X1, curve); /* t3 = B^2 */
|
|
|
- uECC_vli_modSub(Z1, Z1, t5, curve->p, num_words); /* t3 = B^2 - A */
|
|
|
- uECC_vli_modSub(Z1, Z1, t5, curve->p, num_words); /* t3 = B^2 - 2A = x3 */
|
|
|
- uECC_vli_modSub(t5, t5, Z1, curve->p, num_words); /* t5 = A - x3 */
|
|
|
- uECC_vli_modMult_fast(X1, X1, t5, curve); /* t1 = B * (A - x3) */
|
|
|
- /* t4 = B * (A - x3) - y1^4 = y3: */
|
|
|
- uECC_vli_modSub(t4, X1, t4, curve->p, num_words);
|
|
|
-
|
|
|
- uECC_vli_set(X1, Z1, num_words);
|
|
|
- uECC_vli_set(Z1, Y1, num_words);
|
|
|
- uECC_vli_set(Y1, t4, num_words);
|
|
|
+void double_jacobian_default(uECC_word_t *X1, uECC_word_t *Y1,
|
|
|
+ uECC_word_t *Z1, uECC_Curve curve)
|
|
|
+{
|
|
|
+ /* t1 = X, t2 = Y, t3 = Z */
|
|
|
+ uECC_word_t t4[NUM_ECC_WORDS];
|
|
|
+ uECC_word_t t5[NUM_ECC_WORDS];
|
|
|
+ wordcount_t num_words = curve->num_words;
|
|
|
+
|
|
|
+ if (uECC_vli_isZero(Z1, num_words)) {
|
|
|
+ return;
|
|
|
+ }
|
|
|
+
|
|
|
+ uECC_vli_modSquare_fast(t4, Y1, curve); /* t4 = y1^2 */
|
|
|
+ uECC_vli_modMult_fast(t5, X1, t4, curve); /* t5 = x1*y1^2 = A */
|
|
|
+ uECC_vli_modSquare_fast(t4, t4, curve); /* t4 = y1^4 */
|
|
|
+ uECC_vli_modMult_fast(Y1, Y1, Z1, curve); /* t2 = y1*z1 = z3 */
|
|
|
+ uECC_vli_modSquare_fast(Z1, Z1, curve); /* t3 = z1^2 */
|
|
|
+
|
|
|
+ uECC_vli_modAdd(X1, X1, Z1, curve->p, num_words); /* t1 = x1 + z1^2 */
|
|
|
+ uECC_vli_modAdd(Z1, Z1, Z1, curve->p, num_words); /* t3 = 2*z1^2 */
|
|
|
+ uECC_vli_modSub(Z1, X1, Z1, curve->p, num_words); /* t3 = x1 - z1^2 */
|
|
|
+ uECC_vli_modMult_fast(X1, X1, Z1, curve); /* t1 = x1^2 - z1^4 */
|
|
|
+
|
|
|
+ uECC_vli_modAdd(Z1, X1, X1, curve->p, num_words); /* t3 = 2*(x1^2 - z1^4) */
|
|
|
+ uECC_vli_modAdd(X1, X1, Z1, curve->p, num_words); /* t1 = 3*(x1^2 - z1^4) */
|
|
|
+ if (uECC_vli_testBit(X1, 0)) {
|
|
|
+ uECC_word_t l_carry = uECC_vli_add(X1, X1, curve->p, num_words);
|
|
|
+ uECC_vli_rshift1(X1, num_words);
|
|
|
+ X1[num_words - 1] |= l_carry << (uECC_WORD_BITS - 1);
|
|
|
+ } else {
|
|
|
+ uECC_vli_rshift1(X1, num_words);
|
|
|
+ }
|
|
|
+
|
|
|
+ /* t1 = 3/2*(x1^2 - z1^4) = B */
|
|
|
+ uECC_vli_modSquare_fast(Z1, X1, curve); /* t3 = B^2 */
|
|
|
+ uECC_vli_modSub(Z1, Z1, t5, curve->p, num_words); /* t3 = B^2 - A */
|
|
|
+ uECC_vli_modSub(Z1, Z1, t5, curve->p, num_words); /* t3 = B^2 - 2A = x3 */
|
|
|
+ uECC_vli_modSub(t5, t5, Z1, curve->p, num_words); /* t5 = A - x3 */
|
|
|
+ uECC_vli_modMult_fast(X1, X1, t5, curve); /* t1 = B * (A - x3) */
|
|
|
+ /* t4 = B * (A - x3) - y1^4 = y3: */
|
|
|
+ uECC_vli_modSub(t4, X1, t4, curve->p, num_words);
|
|
|
+
|
|
|
+ uECC_vli_set(X1, Z1, num_words);
|
|
|
+ uECC_vli_set(Z1, Y1, num_words);
|
|
|
+ uECC_vli_set(Y1, t4, num_words);
|
|
|
}
|
|
|
|
|
|
void x_side_default(uECC_word_t *result,
|
|
|
- const uECC_word_t *x,
|
|
|
- uECC_Curve curve)
|
|
|
+ const uECC_word_t *x,
|
|
|
+ uECC_Curve curve)
|
|
|
{
|
|
|
- uECC_word_t _3[NUM_ECC_WORDS] = {3}; /* -a = 3 */
|
|
|
- wordcount_t num_words = curve->num_words;
|
|
|
+ uECC_word_t _3[NUM_ECC_WORDS] = {3}; /* -a = 3 */
|
|
|
+ wordcount_t num_words = curve->num_words;
|
|
|
|
|
|
- uECC_vli_modSquare_fast(result, x, curve); /* r = x^2 */
|
|
|
- uECC_vli_modSub(result, result, _3, curve->p, num_words); /* r = x^2 - 3 */
|
|
|
- uECC_vli_modMult_fast(result, result, x, curve); /* r = x^3 - 3x */
|
|
|
- /* r = x^3 - 3x + b: */
|
|
|
- uECC_vli_modAdd(result, result, curve->b, curve->p, num_words);
|
|
|
+ uECC_vli_modSquare_fast(result, x, curve); /* r = x^2 */
|
|
|
+ uECC_vli_modSub(result, result, _3, curve->p, num_words); /* r = x^2 - 3 */
|
|
|
+ uECC_vli_modMult_fast(result, result, x, curve); /* r = x^3 - 3x */
|
|
|
+ /* r = x^3 - 3x + b: */
|
|
|
+ uECC_vli_modAdd(result, result, curve->b, curve->p, num_words);
|
|
|
}
|
|
|
|
|
|
uECC_Curve uECC_secp256r1(void)
|
|
|
{
|
|
|
- return &curve_secp256r1;
|
|
|
-}
|
|
|
-
|
|
|
-void vli_mmod_fast_secp256r1(unsigned int *result, unsigned int*product)
|
|
|
-{
|
|
|
- unsigned int tmp[NUM_ECC_WORDS];
|
|
|
- int carry;
|
|
|
-
|
|
|
- /* t */
|
|
|
- uECC_vli_set(result, product, NUM_ECC_WORDS);
|
|
|
-
|
|
|
- /* s1 */
|
|
|
- tmp[0] = tmp[1] = tmp[2] = 0;
|
|
|
- tmp[3] = product[11];
|
|
|
- tmp[4] = product[12];
|
|
|
- tmp[5] = product[13];
|
|
|
- tmp[6] = product[14];
|
|
|
- tmp[7] = product[15];
|
|
|
- carry = uECC_vli_add(tmp, tmp, tmp, NUM_ECC_WORDS);
|
|
|
- carry += uECC_vli_add(result, result, tmp, NUM_ECC_WORDS);
|
|
|
-
|
|
|
- /* s2 */
|
|
|
- tmp[3] = product[12];
|
|
|
- tmp[4] = product[13];
|
|
|
- tmp[5] = product[14];
|
|
|
- tmp[6] = product[15];
|
|
|
- tmp[7] = 0;
|
|
|
- carry += uECC_vli_add(tmp, tmp, tmp, NUM_ECC_WORDS);
|
|
|
- carry += uECC_vli_add(result, result, tmp, NUM_ECC_WORDS);
|
|
|
-
|
|
|
- /* s3 */
|
|
|
- tmp[0] = product[8];
|
|
|
- tmp[1] = product[9];
|
|
|
- tmp[2] = product[10];
|
|
|
- tmp[3] = tmp[4] = tmp[5] = 0;
|
|
|
- tmp[6] = product[14];
|
|
|
- tmp[7] = product[15];
|
|
|
- carry += uECC_vli_add(result, result, tmp, NUM_ECC_WORDS);
|
|
|
-
|
|
|
- /* s4 */
|
|
|
- tmp[0] = product[9];
|
|
|
- tmp[1] = product[10];
|
|
|
- tmp[2] = product[11];
|
|
|
- tmp[3] = product[13];
|
|
|
- tmp[4] = product[14];
|
|
|
- tmp[5] = product[15];
|
|
|
- tmp[6] = product[13];
|
|
|
- tmp[7] = product[8];
|
|
|
- carry += uECC_vli_add(result, result, tmp, NUM_ECC_WORDS);
|
|
|
-
|
|
|
- /* d1 */
|
|
|
- tmp[0] = product[11];
|
|
|
- tmp[1] = product[12];
|
|
|
- tmp[2] = product[13];
|
|
|
- tmp[3] = tmp[4] = tmp[5] = 0;
|
|
|
- tmp[6] = product[8];
|
|
|
- tmp[7] = product[10];
|
|
|
- carry -= uECC_vli_sub(result, result, tmp, NUM_ECC_WORDS);
|
|
|
-
|
|
|
- /* d2 */
|
|
|
- tmp[0] = product[12];
|
|
|
- tmp[1] = product[13];
|
|
|
- tmp[2] = product[14];
|
|
|
- tmp[3] = product[15];
|
|
|
- tmp[4] = tmp[5] = 0;
|
|
|
- tmp[6] = product[9];
|
|
|
- tmp[7] = product[11];
|
|
|
- carry -= uECC_vli_sub(result, result, tmp, NUM_ECC_WORDS);
|
|
|
-
|
|
|
- /* d3 */
|
|
|
- tmp[0] = product[13];
|
|
|
- tmp[1] = product[14];
|
|
|
- tmp[2] = product[15];
|
|
|
- tmp[3] = product[8];
|
|
|
- tmp[4] = product[9];
|
|
|
- tmp[5] = product[10];
|
|
|
- tmp[6] = 0;
|
|
|
- tmp[7] = product[12];
|
|
|
- carry -= uECC_vli_sub(result, result, tmp, NUM_ECC_WORDS);
|
|
|
-
|
|
|
- /* d4 */
|
|
|
- tmp[0] = product[14];
|
|
|
- tmp[1] = product[15];
|
|
|
- tmp[2] = 0;
|
|
|
- tmp[3] = product[9];
|
|
|
- tmp[4] = product[10];
|
|
|
- tmp[5] = product[11];
|
|
|
- tmp[6] = 0;
|
|
|
- tmp[7] = product[13];
|
|
|
- carry -= uECC_vli_sub(result, result, tmp, NUM_ECC_WORDS);
|
|
|
-
|
|
|
- if (carry < 0) {
|
|
|
- do {
|
|
|
- carry += uECC_vli_add(result, result, curve_secp256r1.p, NUM_ECC_WORDS);
|
|
|
- }
|
|
|
- while (carry < 0);
|
|
|
- } else {
|
|
|
- while (carry ||
|
|
|
- uECC_vli_cmp_unsafe(curve_secp256r1.p, result, NUM_ECC_WORDS) != 1) {
|
|
|
- carry -= uECC_vli_sub(result, result, curve_secp256r1.p, NUM_ECC_WORDS);
|
|
|
- }
|
|
|
- }
|
|
|
+ return &curve_secp256r1;
|
|
|
+}
|
|
|
+
|
|
|
+void vli_mmod_fast_secp256r1(unsigned int *result, unsigned int *product)
|
|
|
+{
|
|
|
+ unsigned int tmp[NUM_ECC_WORDS];
|
|
|
+ int carry;
|
|
|
+
|
|
|
+ /* t */
|
|
|
+ uECC_vli_set(result, product, NUM_ECC_WORDS);
|
|
|
+
|
|
|
+ /* s1 */
|
|
|
+ tmp[0] = tmp[1] = tmp[2] = 0;
|
|
|
+ tmp[3] = product[11];
|
|
|
+ tmp[4] = product[12];
|
|
|
+ tmp[5] = product[13];
|
|
|
+ tmp[6] = product[14];
|
|
|
+ tmp[7] = product[15];
|
|
|
+ carry = uECC_vli_add(tmp, tmp, tmp, NUM_ECC_WORDS);
|
|
|
+ carry += uECC_vli_add(result, result, tmp, NUM_ECC_WORDS);
|
|
|
+
|
|
|
+ /* s2 */
|
|
|
+ tmp[3] = product[12];
|
|
|
+ tmp[4] = product[13];
|
|
|
+ tmp[5] = product[14];
|
|
|
+ tmp[6] = product[15];
|
|
|
+ tmp[7] = 0;
|
|
|
+ carry += uECC_vli_add(tmp, tmp, tmp, NUM_ECC_WORDS);
|
|
|
+ carry += uECC_vli_add(result, result, tmp, NUM_ECC_WORDS);
|
|
|
+
|
|
|
+ /* s3 */
|
|
|
+ tmp[0] = product[8];
|
|
|
+ tmp[1] = product[9];
|
|
|
+ tmp[2] = product[10];
|
|
|
+ tmp[3] = tmp[4] = tmp[5] = 0;
|
|
|
+ tmp[6] = product[14];
|
|
|
+ tmp[7] = product[15];
|
|
|
+ carry += uECC_vli_add(result, result, tmp, NUM_ECC_WORDS);
|
|
|
+
|
|
|
+ /* s4 */
|
|
|
+ tmp[0] = product[9];
|
|
|
+ tmp[1] = product[10];
|
|
|
+ tmp[2] = product[11];
|
|
|
+ tmp[3] = product[13];
|
|
|
+ tmp[4] = product[14];
|
|
|
+ tmp[5] = product[15];
|
|
|
+ tmp[6] = product[13];
|
|
|
+ tmp[7] = product[8];
|
|
|
+ carry += uECC_vli_add(result, result, tmp, NUM_ECC_WORDS);
|
|
|
+
|
|
|
+ /* d1 */
|
|
|
+ tmp[0] = product[11];
|
|
|
+ tmp[1] = product[12];
|
|
|
+ tmp[2] = product[13];
|
|
|
+ tmp[3] = tmp[4] = tmp[5] = 0;
|
|
|
+ tmp[6] = product[8];
|
|
|
+ tmp[7] = product[10];
|
|
|
+ carry -= uECC_vli_sub(result, result, tmp, NUM_ECC_WORDS);
|
|
|
+
|
|
|
+ /* d2 */
|
|
|
+ tmp[0] = product[12];
|
|
|
+ tmp[1] = product[13];
|
|
|
+ tmp[2] = product[14];
|
|
|
+ tmp[3] = product[15];
|
|
|
+ tmp[4] = tmp[5] = 0;
|
|
|
+ tmp[6] = product[9];
|
|
|
+ tmp[7] = product[11];
|
|
|
+ carry -= uECC_vli_sub(result, result, tmp, NUM_ECC_WORDS);
|
|
|
+
|
|
|
+ /* d3 */
|
|
|
+ tmp[0] = product[13];
|
|
|
+ tmp[1] = product[14];
|
|
|
+ tmp[2] = product[15];
|
|
|
+ tmp[3] = product[8];
|
|
|
+ tmp[4] = product[9];
|
|
|
+ tmp[5] = product[10];
|
|
|
+ tmp[6] = 0;
|
|
|
+ tmp[7] = product[12];
|
|
|
+ carry -= uECC_vli_sub(result, result, tmp, NUM_ECC_WORDS);
|
|
|
+
|
|
|
+ /* d4 */
|
|
|
+ tmp[0] = product[14];
|
|
|
+ tmp[1] = product[15];
|
|
|
+ tmp[2] = 0;
|
|
|
+ tmp[3] = product[9];
|
|
|
+ tmp[4] = product[10];
|
|
|
+ tmp[5] = product[11];
|
|
|
+ tmp[6] = 0;
|
|
|
+ tmp[7] = product[13];
|
|
|
+ carry -= uECC_vli_sub(result, result, tmp, NUM_ECC_WORDS);
|
|
|
+
|
|
|
+ if (carry < 0) {
|
|
|
+ do {
|
|
|
+ carry += uECC_vli_add(result, result, curve_secp256r1.p, NUM_ECC_WORDS);
|
|
|
+ } while (carry < 0);
|
|
|
+ } else {
|
|
|
+ while (carry ||
|
|
|
+ uECC_vli_cmp_unsafe(curve_secp256r1.p, result, NUM_ECC_WORDS) != 1) {
|
|
|
+ carry -= uECC_vli_sub(result, result, curve_secp256r1.p, NUM_ECC_WORDS);
|
|
|
+ }
|
|
|
+ }
|
|
|
}
|
|
|
|
|
|
uECC_word_t EccPoint_isZero(const uECC_word_t *point, uECC_Curve curve)
|
|
|
{
|
|
|
- return uECC_vli_isZero(point, curve->num_words * 2);
|
|
|
+ return uECC_vli_isZero(point, curve->num_words * 2);
|
|
|
}
|
|
|
|
|
|
-void apply_z(uECC_word_t * X1, uECC_word_t * Y1, const uECC_word_t * const Z,
|
|
|
- uECC_Curve curve)
|
|
|
+void apply_z(uECC_word_t *X1, uECC_word_t *Y1, const uECC_word_t *const Z,
|
|
|
+ uECC_Curve curve)
|
|
|
{
|
|
|
- uECC_word_t t1[NUM_ECC_WORDS];
|
|
|
+ uECC_word_t t1[NUM_ECC_WORDS];
|
|
|
|
|
|
- uECC_vli_modSquare_fast(t1, Z, curve); /* z^2 */
|
|
|
- uECC_vli_modMult_fast(X1, X1, t1, curve); /* x1 * z^2 */
|
|
|
- uECC_vli_modMult_fast(t1, t1, Z, curve); /* z^3 */
|
|
|
- uECC_vli_modMult_fast(Y1, Y1, t1, curve); /* y1 * z^3 */
|
|
|
+ uECC_vli_modSquare_fast(t1, Z, curve); /* z^2 */
|
|
|
+ uECC_vli_modMult_fast(X1, X1, t1, curve); /* x1 * z^2 */
|
|
|
+ uECC_vli_modMult_fast(t1, t1, Z, curve); /* z^3 */
|
|
|
+ uECC_vli_modMult_fast(Y1, Y1, t1, curve); /* y1 * z^3 */
|
|
|
}
|
|
|
|
|
|
/* P = (x1, y1) => 2P, (x2, y2) => P' */
|
|
|
-static void XYcZ_initial_double(uECC_word_t * X1, uECC_word_t * Y1,
|
|
|
- uECC_word_t * X2, uECC_word_t * Y2,
|
|
|
- const uECC_word_t * const initial_Z,
|
|
|
- uECC_Curve curve)
|
|
|
-{
|
|
|
- uECC_word_t z[NUM_ECC_WORDS];
|
|
|
- wordcount_t num_words = curve->num_words;
|
|
|
- if (initial_Z) {
|
|
|
- uECC_vli_set(z, initial_Z, num_words);
|
|
|
- } else {
|
|
|
- uECC_vli_clear(z, num_words);
|
|
|
- z[0] = 1;
|
|
|
- }
|
|
|
-
|
|
|
- uECC_vli_set(X2, X1, num_words);
|
|
|
- uECC_vli_set(Y2, Y1, num_words);
|
|
|
-
|
|
|
- apply_z(X1, Y1, z, curve);
|
|
|
- curve->double_jacobian(X1, Y1, z, curve);
|
|
|
- apply_z(X2, Y2, z, curve);
|
|
|
-}
|
|
|
-
|
|
|
-void XYcZ_add(uECC_word_t * X1, uECC_word_t * Y1,
|
|
|
- uECC_word_t * X2, uECC_word_t * Y2,
|
|
|
- uECC_Curve curve)
|
|
|
-{
|
|
|
- /* t1 = X1, t2 = Y1, t3 = X2, t4 = Y2 */
|
|
|
- uECC_word_t t5[NUM_ECC_WORDS];
|
|
|
- wordcount_t num_words = curve->num_words;
|
|
|
-
|
|
|
- uECC_vli_modSub(t5, X2, X1, curve->p, num_words); /* t5 = x2 - x1 */
|
|
|
- uECC_vli_modSquare_fast(t5, t5, curve); /* t5 = (x2 - x1)^2 = A */
|
|
|
- uECC_vli_modMult_fast(X1, X1, t5, curve); /* t1 = x1*A = B */
|
|
|
- uECC_vli_modMult_fast(X2, X2, t5, curve); /* t3 = x2*A = C */
|
|
|
- uECC_vli_modSub(Y2, Y2, Y1, curve->p, num_words); /* t4 = y2 - y1 */
|
|
|
- uECC_vli_modSquare_fast(t5, Y2, curve); /* t5 = (y2 - y1)^2 = D */
|
|
|
-
|
|
|
- uECC_vli_modSub(t5, t5, X1, curve->p, num_words); /* t5 = D - B */
|
|
|
- uECC_vli_modSub(t5, t5, X2, curve->p, num_words); /* t5 = D - B - C = x3 */
|
|
|
- uECC_vli_modSub(X2, X2, X1, curve->p, num_words); /* t3 = C - B */
|
|
|
- uECC_vli_modMult_fast(Y1, Y1, X2, curve); /* t2 = y1*(C - B) */
|
|
|
- uECC_vli_modSub(X2, X1, t5, curve->p, num_words); /* t3 = B - x3 */
|
|
|
- uECC_vli_modMult_fast(Y2, Y2, X2, curve); /* t4 = (y2 - y1)*(B - x3) */
|
|
|
- uECC_vli_modSub(Y2, Y2, Y1, curve->p, num_words); /* t4 = y3 */
|
|
|
-
|
|
|
- uECC_vli_set(X2, t5, num_words);
|
|
|
+static void XYcZ_initial_double(uECC_word_t *X1, uECC_word_t *Y1,
|
|
|
+ uECC_word_t *X2, uECC_word_t *Y2,
|
|
|
+ const uECC_word_t *const initial_Z,
|
|
|
+ uECC_Curve curve)
|
|
|
+{
|
|
|
+ uECC_word_t z[NUM_ECC_WORDS];
|
|
|
+ wordcount_t num_words = curve->num_words;
|
|
|
+ if (initial_Z) {
|
|
|
+ uECC_vli_set(z, initial_Z, num_words);
|
|
|
+ } else {
|
|
|
+ uECC_vli_clear(z, num_words);
|
|
|
+ z[0] = 1;
|
|
|
+ }
|
|
|
+
|
|
|
+ uECC_vli_set(X2, X1, num_words);
|
|
|
+ uECC_vli_set(Y2, Y1, num_words);
|
|
|
+
|
|
|
+ apply_z(X1, Y1, z, curve);
|
|
|
+ curve->double_jacobian(X1, Y1, z, curve);
|
|
|
+ apply_z(X2, Y2, z, curve);
|
|
|
+}
|
|
|
+
|
|
|
+void XYcZ_add(uECC_word_t *X1, uECC_word_t *Y1,
|
|
|
+ uECC_word_t *X2, uECC_word_t *Y2,
|
|
|
+ uECC_Curve curve)
|
|
|
+{
|
|
|
+ /* t1 = X1, t2 = Y1, t3 = X2, t4 = Y2 */
|
|
|
+ uECC_word_t t5[NUM_ECC_WORDS];
|
|
|
+ wordcount_t num_words = curve->num_words;
|
|
|
+
|
|
|
+ uECC_vli_modSub(t5, X2, X1, curve->p, num_words); /* t5 = x2 - x1 */
|
|
|
+ uECC_vli_modSquare_fast(t5, t5, curve); /* t5 = (x2 - x1)^2 = A */
|
|
|
+ uECC_vli_modMult_fast(X1, X1, t5, curve); /* t1 = x1*A = B */
|
|
|
+ uECC_vli_modMult_fast(X2, X2, t5, curve); /* t3 = x2*A = C */
|
|
|
+ uECC_vli_modSub(Y2, Y2, Y1, curve->p, num_words); /* t4 = y2 - y1 */
|
|
|
+ uECC_vli_modSquare_fast(t5, Y2, curve); /* t5 = (y2 - y1)^2 = D */
|
|
|
+
|
|
|
+ uECC_vli_modSub(t5, t5, X1, curve->p, num_words); /* t5 = D - B */
|
|
|
+ uECC_vli_modSub(t5, t5, X2, curve->p, num_words); /* t5 = D - B - C = x3 */
|
|
|
+ uECC_vli_modSub(X2, X2, X1, curve->p, num_words); /* t3 = C - B */
|
|
|
+ uECC_vli_modMult_fast(Y1, Y1, X2, curve); /* t2 = y1*(C - B) */
|
|
|
+ uECC_vli_modSub(X2, X1, t5, curve->p, num_words); /* t3 = B - x3 */
|
|
|
+ uECC_vli_modMult_fast(Y2, Y2, X2, curve); /* t4 = (y2 - y1)*(B - x3) */
|
|
|
+ uECC_vli_modSub(Y2, Y2, Y1, curve->p, num_words); /* t4 = y3 */
|
|
|
+
|
|
|
+ uECC_vli_set(X2, t5, num_words);
|
|
|
}
|
|
|
|
|
|
/* Input P = (x1, y1, Z), Q = (x2, y2, Z)
|
|
|
Output P + Q = (x3, y3, Z3), P - Q = (x3', y3', Z3)
|
|
|
or P => P - Q, Q => P + Q
|
|
|
*/
|
|
|
-static void XYcZ_addC(uECC_word_t * X1, uECC_word_t * Y1,
|
|
|
- uECC_word_t * X2, uECC_word_t * Y2,
|
|
|
- uECC_Curve curve)
|
|
|
+static void XYcZ_addC(uECC_word_t *X1, uECC_word_t *Y1,
|
|
|
+ uECC_word_t *X2, uECC_word_t *Y2,
|
|
|
+ uECC_Curve curve)
|
|
|
{
|
|
|
- /* t1 = X1, t2 = Y1, t3 = X2, t4 = Y2 */
|
|
|
- uECC_word_t t5[NUM_ECC_WORDS];
|
|
|
- uECC_word_t t6[NUM_ECC_WORDS];
|
|
|
- uECC_word_t t7[NUM_ECC_WORDS];
|
|
|
- wordcount_t num_words = curve->num_words;
|
|
|
+ /* t1 = X1, t2 = Y1, t3 = X2, t4 = Y2 */
|
|
|
+ uECC_word_t t5[NUM_ECC_WORDS];
|
|
|
+ uECC_word_t t6[NUM_ECC_WORDS];
|
|
|
+ uECC_word_t t7[NUM_ECC_WORDS];
|
|
|
+ wordcount_t num_words = curve->num_words;
|
|
|
|
|
|
- uECC_vli_modSub(t5, X2, X1, curve->p, num_words); /* t5 = x2 - x1 */
|
|
|
- uECC_vli_modSquare_fast(t5, t5, curve); /* t5 = (x2 - x1)^2 = A */
|
|
|
- uECC_vli_modMult_fast(X1, X1, t5, curve); /* t1 = x1*A = B */
|
|
|
- uECC_vli_modMult_fast(X2, X2, t5, curve); /* t3 = x2*A = C */
|
|
|
- uECC_vli_modAdd(t5, Y2, Y1, curve->p, num_words); /* t5 = y2 + y1 */
|
|
|
- uECC_vli_modSub(Y2, Y2, Y1, curve->p, num_words); /* t4 = y2 - y1 */
|
|
|
+ uECC_vli_modSub(t5, X2, X1, curve->p, num_words); /* t5 = x2 - x1 */
|
|
|
+ uECC_vli_modSquare_fast(t5, t5, curve); /* t5 = (x2 - x1)^2 = A */
|
|
|
+ uECC_vli_modMult_fast(X1, X1, t5, curve); /* t1 = x1*A = B */
|
|
|
+ uECC_vli_modMult_fast(X2, X2, t5, curve); /* t3 = x2*A = C */
|
|
|
+ uECC_vli_modAdd(t5, Y2, Y1, curve->p, num_words); /* t5 = y2 + y1 */
|
|
|
+ uECC_vli_modSub(Y2, Y2, Y1, curve->p, num_words); /* t4 = y2 - y1 */
|
|
|
|
|
|
- uECC_vli_modSub(t6, X2, X1, curve->p, num_words); /* t6 = C - B */
|
|
|
- uECC_vli_modMult_fast(Y1, Y1, t6, curve); /* t2 = y1 * (C - B) = E */
|
|
|
- uECC_vli_modAdd(t6, X1, X2, curve->p, num_words); /* t6 = B + C */
|
|
|
- uECC_vli_modSquare_fast(X2, Y2, curve); /* t3 = (y2 - y1)^2 = D */
|
|
|
- uECC_vli_modSub(X2, X2, t6, curve->p, num_words); /* t3 = D - (B + C) = x3 */
|
|
|
+ uECC_vli_modSub(t6, X2, X1, curve->p, num_words); /* t6 = C - B */
|
|
|
+ uECC_vli_modMult_fast(Y1, Y1, t6, curve); /* t2 = y1 * (C - B) = E */
|
|
|
+ uECC_vli_modAdd(t6, X1, X2, curve->p, num_words); /* t6 = B + C */
|
|
|
+ uECC_vli_modSquare_fast(X2, Y2, curve); /* t3 = (y2 - y1)^2 = D */
|
|
|
+ uECC_vli_modSub(X2, X2, t6, curve->p, num_words); /* t3 = D - (B + C) = x3 */
|
|
|
|
|
|
- uECC_vli_modSub(t7, X1, X2, curve->p, num_words); /* t7 = B - x3 */
|
|
|
- uECC_vli_modMult_fast(Y2, Y2, t7, curve); /* t4 = (y2 - y1)*(B - x3) */
|
|
|
- /* t4 = (y2 - y1)*(B - x3) - E = y3: */
|
|
|
- uECC_vli_modSub(Y2, Y2, Y1, curve->p, num_words);
|
|
|
+ uECC_vli_modSub(t7, X1, X2, curve->p, num_words); /* t7 = B - x3 */
|
|
|
+ uECC_vli_modMult_fast(Y2, Y2, t7, curve); /* t4 = (y2 - y1)*(B - x3) */
|
|
|
+ /* t4 = (y2 - y1)*(B - x3) - E = y3: */
|
|
|
+ uECC_vli_modSub(Y2, Y2, Y1, curve->p, num_words);
|
|
|
|
|
|
- uECC_vli_modSquare_fast(t7, t5, curve); /* t7 = (y2 + y1)^2 = F */
|
|
|
- uECC_vli_modSub(t7, t7, t6, curve->p, num_words); /* t7 = F - (B + C) = x3' */
|
|
|
- uECC_vli_modSub(t6, t7, X1, curve->p, num_words); /* t6 = x3' - B */
|
|
|
- uECC_vli_modMult_fast(t6, t6, t5, curve); /* t6 = (y2+y1)*(x3' - B) */
|
|
|
- /* t2 = (y2+y1)*(x3' - B) - E = y3': */
|
|
|
- uECC_vli_modSub(Y1, t6, Y1, curve->p, num_words);
|
|
|
+ uECC_vli_modSquare_fast(t7, t5, curve); /* t7 = (y2 + y1)^2 = F */
|
|
|
+ uECC_vli_modSub(t7, t7, t6, curve->p, num_words); /* t7 = F - (B + C) = x3' */
|
|
|
+ uECC_vli_modSub(t6, t7, X1, curve->p, num_words); /* t6 = x3' - B */
|
|
|
+ uECC_vli_modMult_fast(t6, t6, t5, curve); /* t6 = (y2+y1)*(x3' - B) */
|
|
|
+ /* t2 = (y2+y1)*(x3' - B) - E = y3': */
|
|
|
+ uECC_vli_modSub(Y1, t6, Y1, curve->p, num_words);
|
|
|
|
|
|
- uECC_vli_set(X1, t7, num_words);
|
|
|
+ uECC_vli_set(X1, t7, num_words);
|
|
|
}
|
|
|
|
|
|
-void EccPoint_mult(uECC_word_t * result, const uECC_word_t * point,
|
|
|
- const uECC_word_t * scalar,
|
|
|
- const uECC_word_t * initial_Z,
|
|
|
- bitcount_t num_bits, uECC_Curve curve)
|
|
|
+void EccPoint_mult(uECC_word_t *result, const uECC_word_t *point,
|
|
|
+ const uECC_word_t *scalar,
|
|
|
+ const uECC_word_t *initial_Z,
|
|
|
+ bitcount_t num_bits, uECC_Curve curve)
|
|
|
{
|
|
|
- /* R0 and R1 */
|
|
|
- uECC_word_t Rx[2][NUM_ECC_WORDS];
|
|
|
- uECC_word_t Ry[2][NUM_ECC_WORDS];
|
|
|
- uECC_word_t z[NUM_ECC_WORDS];
|
|
|
- bitcount_t i;
|
|
|
- uECC_word_t nb;
|
|
|
- wordcount_t num_words = curve->num_words;
|
|
|
+ /* R0 and R1 */
|
|
|
+ uECC_word_t Rx[2][NUM_ECC_WORDS];
|
|
|
+ uECC_word_t Ry[2][NUM_ECC_WORDS];
|
|
|
+ uECC_word_t z[NUM_ECC_WORDS];
|
|
|
+ bitcount_t i;
|
|
|
+ uECC_word_t nb;
|
|
|
+ wordcount_t num_words = curve->num_words;
|
|
|
|
|
|
- uECC_vli_set(Rx[1], point, num_words);
|
|
|
- uECC_vli_set(Ry[1], point + num_words, num_words);
|
|
|
+ uECC_vli_set(Rx[1], point, num_words);
|
|
|
+ uECC_vli_set(Ry[1], point + num_words, num_words);
|
|
|
|
|
|
- XYcZ_initial_double(Rx[1], Ry[1], Rx[0], Ry[0], initial_Z, curve);
|
|
|
+ XYcZ_initial_double(Rx[1], Ry[1], Rx[0], Ry[0], initial_Z, curve);
|
|
|
|
|
|
- for (i = num_bits - 2; i > 0; --i) {
|
|
|
- nb = !uECC_vli_testBit(scalar, i);
|
|
|
- XYcZ_addC(Rx[1 - nb], Ry[1 - nb], Rx[nb], Ry[nb], curve);
|
|
|
- XYcZ_add(Rx[nb], Ry[nb], Rx[1 - nb], Ry[1 - nb], curve);
|
|
|
- }
|
|
|
+ for (i = num_bits - 2; i > 0; --i) {
|
|
|
+ nb = !uECC_vli_testBit(scalar, i);
|
|
|
+ XYcZ_addC(Rx[1 - nb], Ry[1 - nb], Rx[nb], Ry[nb], curve);
|
|
|
+ XYcZ_add(Rx[nb], Ry[nb], Rx[1 - nb], Ry[1 - nb], curve);
|
|
|
+ }
|
|
|
|
|
|
- nb = !uECC_vli_testBit(scalar, 0);
|
|
|
- XYcZ_addC(Rx[1 - nb], Ry[1 - nb], Rx[nb], Ry[nb], curve);
|
|
|
+ nb = !uECC_vli_testBit(scalar, 0);
|
|
|
+ XYcZ_addC(Rx[1 - nb], Ry[1 - nb], Rx[nb], Ry[nb], curve);
|
|
|
|
|
|
- /* Find final 1/Z value. */
|
|
|
- uECC_vli_modSub(z, Rx[1], Rx[0], curve->p, num_words); /* X1 - X0 */
|
|
|
- uECC_vli_modMult_fast(z, z, Ry[1 - nb], curve); /* Yb * (X1 - X0) */
|
|
|
- uECC_vli_modMult_fast(z, z, point, curve); /* xP * Yb * (X1 - X0) */
|
|
|
- uECC_vli_modInv(z, z, curve->p, num_words); /* 1 / (xP * Yb * (X1 - X0))*/
|
|
|
- /* yP / (xP * Yb * (X1 - X0)) */
|
|
|
- uECC_vli_modMult_fast(z, z, point + num_words, curve);
|
|
|
- /* Xb * yP / (xP * Yb * (X1 - X0)) */
|
|
|
- uECC_vli_modMult_fast(z, z, Rx[1 - nb], curve);
|
|
|
- /* End 1/Z calculation */
|
|
|
+ /* Find final 1/Z value. */
|
|
|
+ uECC_vli_modSub(z, Rx[1], Rx[0], curve->p, num_words); /* X1 - X0 */
|
|
|
+ uECC_vli_modMult_fast(z, z, Ry[1 - nb], curve); /* Yb * (X1 - X0) */
|
|
|
+ uECC_vli_modMult_fast(z, z, point, curve); /* xP * Yb * (X1 - X0) */
|
|
|
+ uECC_vli_modInv(z, z, curve->p, num_words); /* 1 / (xP * Yb * (X1 - X0))*/
|
|
|
+ /* yP / (xP * Yb * (X1 - X0)) */
|
|
|
+ uECC_vli_modMult_fast(z, z, point + num_words, curve);
|
|
|
+ /* Xb * yP / (xP * Yb * (X1 - X0)) */
|
|
|
+ uECC_vli_modMult_fast(z, z, Rx[1 - nb], curve);
|
|
|
+ /* End 1/Z calculation */
|
|
|
|
|
|
- XYcZ_add(Rx[nb], Ry[nb], Rx[1 - nb], Ry[1 - nb], curve);
|
|
|
- apply_z(Rx[0], Ry[0], z, curve);
|
|
|
+ XYcZ_add(Rx[nb], Ry[nb], Rx[1 - nb], Ry[1 - nb], curve);
|
|
|
+ apply_z(Rx[0], Ry[0], z, curve);
|
|
|
|
|
|
- uECC_vli_set(result, Rx[0], num_words);
|
|
|
- uECC_vli_set(result + num_words, Ry[0], num_words);
|
|
|
+ uECC_vli_set(result, Rx[0], num_words);
|
|
|
+ uECC_vli_set(result + num_words, Ry[0], num_words);
|
|
|
}
|
|
|
|
|
|
-uECC_word_t regularize_k(const uECC_word_t * const k, uECC_word_t *k0,
|
|
|
- uECC_word_t *k1, uECC_Curve curve)
|
|
|
+uECC_word_t regularize_k(const uECC_word_t *const k, uECC_word_t *k0,
|
|
|
+ uECC_word_t *k1, uECC_Curve curve)
|
|
|
{
|
|
|
|
|
|
- wordcount_t num_n_words = BITS_TO_WORDS(curve->num_n_bits);
|
|
|
+ wordcount_t num_n_words = BITS_TO_WORDS(curve->num_n_bits);
|
|
|
|
|
|
- bitcount_t num_n_bits = curve->num_n_bits;
|
|
|
+ bitcount_t num_n_bits = curve->num_n_bits;
|
|
|
|
|
|
- uECC_word_t carry = uECC_vli_add(k0, k, curve->n, num_n_words) ||
|
|
|
- (num_n_bits < ((bitcount_t)num_n_words * uECC_WORD_SIZE * 8) &&
|
|
|
- uECC_vli_testBit(k0, num_n_bits));
|
|
|
+ uECC_word_t carry = uECC_vli_add(k0, k, curve->n, num_n_words) ||
|
|
|
+ (num_n_bits < ((bitcount_t)num_n_words * uECC_WORD_SIZE * 8) &&
|
|
|
+ uECC_vli_testBit(k0, num_n_bits));
|
|
|
|
|
|
- uECC_vli_add(k1, k0, curve->n, num_n_words);
|
|
|
+ uECC_vli_add(k1, k0, curve->n, num_n_words);
|
|
|
|
|
|
- return carry;
|
|
|
+ return carry;
|
|
|
}
|
|
|
|
|
|
uECC_word_t EccPoint_compute_public_key(uECC_word_t *result,
|
|
|
- uECC_word_t *private_key,
|
|
|
- uECC_Curve curve)
|
|
|
+ uECC_word_t *private_key,
|
|
|
+ uECC_Curve curve)
|
|
|
{
|
|
|
|
|
|
- uECC_word_t tmp1[NUM_ECC_WORDS];
|
|
|
- uECC_word_t tmp2[NUM_ECC_WORDS];
|
|
|
- uECC_word_t *p2[2] = {tmp1, tmp2};
|
|
|
- uECC_word_t carry;
|
|
|
+ uECC_word_t tmp1[NUM_ECC_WORDS];
|
|
|
+ uECC_word_t tmp2[NUM_ECC_WORDS];
|
|
|
+ uECC_word_t *p2[2] = {tmp1, tmp2};
|
|
|
+ uECC_word_t carry;
|
|
|
|
|
|
- /* Regularize the bitcount for the private key so that attackers cannot
|
|
|
- * use a side channel attack to learn the number of leading zeros. */
|
|
|
- carry = regularize_k(private_key, tmp1, tmp2, curve);
|
|
|
+ /* Regularize the bitcount for the private key so that attackers cannot
|
|
|
+ * use a side channel attack to learn the number of leading zeros. */
|
|
|
+ carry = regularize_k(private_key, tmp1, tmp2, curve);
|
|
|
|
|
|
- EccPoint_mult(result, curve->G, p2[!carry], 0, curve->num_n_bits + 1, curve);
|
|
|
+ EccPoint_mult(result, curve->G, p2[!carry], 0, curve->num_n_bits + 1, curve);
|
|
|
|
|
|
- if (EccPoint_isZero(result, curve)) {
|
|
|
- return 0;
|
|
|
- }
|
|
|
- return 1;
|
|
|
+ if (EccPoint_isZero(result, curve)) {
|
|
|
+ return 0;
|
|
|
+ }
|
|
|
+ return 1;
|
|
|
}
|
|
|
|
|
|
/* Converts an integer in uECC native format to big-endian bytes. */
|
|
|
void uECC_vli_nativeToBytes(uint8_t *bytes, int num_bytes,
|
|
|
- const unsigned int *native)
|
|
|
+ const unsigned int *native)
|
|
|
{
|
|
|
- wordcount_t i;
|
|
|
- for (i = 0; i < num_bytes; ++i) {
|
|
|
- unsigned b = num_bytes - 1 - i;
|
|
|
- bytes[i] = native[b / uECC_WORD_SIZE] >> (8 * (b % uECC_WORD_SIZE));
|
|
|
- }
|
|
|
+ wordcount_t i;
|
|
|
+ for (i = 0; i < num_bytes; ++i) {
|
|
|
+ unsigned b = num_bytes - 1 - i;
|
|
|
+ bytes[i] = native[b / uECC_WORD_SIZE] >> (8 * (b % uECC_WORD_SIZE));
|
|
|
+ }
|
|
|
}
|
|
|
|
|
|
/* Converts big-endian bytes to an integer in uECC native format. */
|
|
|
void uECC_vli_bytesToNative(unsigned int *native, const uint8_t *bytes,
|
|
|
- int num_bytes)
|
|
|
+ int num_bytes)
|
|
|
{
|
|
|
- wordcount_t i;
|
|
|
- uECC_vli_clear(native, (num_bytes + (uECC_WORD_SIZE - 1)) / uECC_WORD_SIZE);
|
|
|
- for (i = 0; i < num_bytes; ++i) {
|
|
|
- unsigned b = num_bytes - 1 - i;
|
|
|
- native[b / uECC_WORD_SIZE] |=
|
|
|
- (uECC_word_t)bytes[i] << (8 * (b % uECC_WORD_SIZE));
|
|
|
- }
|
|
|
+ wordcount_t i;
|
|
|
+ uECC_vli_clear(native, (num_bytes + (uECC_WORD_SIZE - 1)) / uECC_WORD_SIZE);
|
|
|
+ for (i = 0; i < num_bytes; ++i) {
|
|
|
+ unsigned b = num_bytes - 1 - i;
|
|
|
+ native[b / uECC_WORD_SIZE] |=
|
|
|
+ (uECC_word_t)bytes[i] << (8 * (b % uECC_WORD_SIZE));
|
|
|
+ }
|
|
|
}
|
|
|
|
|
|
int uECC_generate_random_int(uECC_word_t *random, const uECC_word_t *top,
|
|
|
- wordcount_t num_words)
|
|
|
+ wordcount_t num_words)
|
|
|
{
|
|
|
- uECC_word_t mask = (uECC_word_t)-1;
|
|
|
- uECC_word_t tries;
|
|
|
- bitcount_t num_bits = uECC_vli_numBits(top, num_words);
|
|
|
+ uECC_word_t mask = (uECC_word_t) - 1;
|
|
|
+ uECC_word_t tries;
|
|
|
+ bitcount_t num_bits = uECC_vli_numBits(top, num_words);
|
|
|
|
|
|
- if (!g_rng_function) {
|
|
|
- return 0;
|
|
|
- }
|
|
|
+ if (!g_rng_function) {
|
|
|
+ return 0;
|
|
|
+ }
|
|
|
|
|
|
- for (tries = 0; tries < uECC_RNG_MAX_TRIES; ++tries) {
|
|
|
- if (!g_rng_function((uint8_t *)random, num_words * uECC_WORD_SIZE)) {
|
|
|
- return 0;
|
|
|
- }
|
|
|
- random[num_words - 1] &=
|
|
|
- mask >> ((bitcount_t)(num_words * uECC_WORD_SIZE * 8 - num_bits));
|
|
|
- if (!uECC_vli_isZero(random, num_words) &&
|
|
|
- uECC_vli_cmp(top, random, num_words) == 1) {
|
|
|
- return 1;
|
|
|
- }
|
|
|
- }
|
|
|
- return 0;
|
|
|
+ for (tries = 0; tries < uECC_RNG_MAX_TRIES; ++tries) {
|
|
|
+ if (!g_rng_function((uint8_t *)random, num_words * uECC_WORD_SIZE)) {
|
|
|
+ return 0;
|
|
|
+ }
|
|
|
+ random[num_words - 1] &=
|
|
|
+ mask >> ((bitcount_t)(num_words * uECC_WORD_SIZE * 8 - num_bits));
|
|
|
+ if (!uECC_vli_isZero(random, num_words) &&
|
|
|
+ uECC_vli_cmp(top, random, num_words) == 1) {
|
|
|
+ return 1;
|
|
|
+ }
|
|
|
+ }
|
|
|
+ return 0;
|
|
|
}
|
|
|
|
|
|
|
|
|
int uECC_valid_point(const uECC_word_t *point, uECC_Curve curve)
|
|
|
{
|
|
|
- uECC_word_t tmp1[NUM_ECC_WORDS];
|
|
|
- uECC_word_t tmp2[NUM_ECC_WORDS];
|
|
|
- wordcount_t num_words = curve->num_words;
|
|
|
+ uECC_word_t tmp1[NUM_ECC_WORDS];
|
|
|
+ uECC_word_t tmp2[NUM_ECC_WORDS];
|
|
|
+ wordcount_t num_words = curve->num_words;
|
|
|
|
|
|
- /* The point at infinity is invalid. */
|
|
|
- if (EccPoint_isZero(point, curve)) {
|
|
|
- return -1;
|
|
|
- }
|
|
|
+ /* The point at infinity is invalid. */
|
|
|
+ if (EccPoint_isZero(point, curve)) {
|
|
|
+ return -1;
|
|
|
+ }
|
|
|
|
|
|
- /* x and y must be smaller than p. */
|
|
|
- if (uECC_vli_cmp_unsafe(curve->p, point, num_words) != 1 ||
|
|
|
- uECC_vli_cmp_unsafe(curve->p, point + num_words, num_words) != 1) {
|
|
|
- return -2;
|
|
|
- }
|
|
|
+ /* x and y must be smaller than p. */
|
|
|
+ if (uECC_vli_cmp_unsafe(curve->p, point, num_words) != 1 ||
|
|
|
+ uECC_vli_cmp_unsafe(curve->p, point + num_words, num_words) != 1) {
|
|
|
+ return -2;
|
|
|
+ }
|
|
|
|
|
|
- uECC_vli_modSquare_fast(tmp1, point + num_words, curve);
|
|
|
- curve->x_side(tmp2, point, curve); /* tmp2 = x^3 + ax + b */
|
|
|
+ uECC_vli_modSquare_fast(tmp1, point + num_words, curve);
|
|
|
+ curve->x_side(tmp2, point, curve); /* tmp2 = x^3 + ax + b */
|
|
|
|
|
|
- /* Make sure that y^2 == x^3 + ax + b */
|
|
|
- if (uECC_vli_equal(tmp1, tmp2, num_words) != 0)
|
|
|
- return -3;
|
|
|
+ /* Make sure that y^2 == x^3 + ax + b */
|
|
|
+ if (uECC_vli_equal(tmp1, tmp2, num_words) != 0) {
|
|
|
+ return -3;
|
|
|
+ }
|
|
|
|
|
|
- return 0;
|
|
|
+ return 0;
|
|
|
}
|
|
|
|
|
|
int uECC_valid_public_key(const uint8_t *public_key, uECC_Curve curve)
|
|
|
{
|
|
|
|
|
|
- uECC_word_t _public[NUM_ECC_WORDS * 2];
|
|
|
+ uECC_word_t _public[NUM_ECC_WORDS * 2];
|
|
|
|
|
|
- uECC_vli_bytesToNative(_public, public_key, curve->num_bytes);
|
|
|
- uECC_vli_bytesToNative(
|
|
|
- _public + curve->num_words,
|
|
|
- public_key + curve->num_bytes,
|
|
|
- curve->num_bytes);
|
|
|
+ uECC_vli_bytesToNative(_public, public_key, curve->num_bytes);
|
|
|
+ uECC_vli_bytesToNative(
|
|
|
+ _public + curve->num_words,
|
|
|
+ public_key + curve->num_bytes,
|
|
|
+ curve->num_bytes);
|
|
|
|
|
|
- if (uECC_vli_cmp_unsafe(_public, curve->G, NUM_ECC_WORDS * 2) == 0) {
|
|
|
- return -4;
|
|
|
- }
|
|
|
+ if (uECC_vli_cmp_unsafe(_public, curve->G, NUM_ECC_WORDS * 2) == 0) {
|
|
|
+ return -4;
|
|
|
+ }
|
|
|
|
|
|
- return uECC_valid_point(_public, curve);
|
|
|
+ return uECC_valid_point(_public, curve);
|
|
|
}
|
|
|
|
|
|
int uECC_compute_public_key(const uint8_t *private_key, uint8_t *public_key,
|
|
|
- uECC_Curve curve)
|
|
|
+ uECC_Curve curve)
|
|
|
{
|
|
|
|
|
|
- uECC_word_t _private[NUM_ECC_WORDS];
|
|
|
- uECC_word_t _public[NUM_ECC_WORDS * 2];
|
|
|
+ uECC_word_t _private[NUM_ECC_WORDS];
|
|
|
+ uECC_word_t _public[NUM_ECC_WORDS * 2];
|
|
|
|
|
|
- uECC_vli_bytesToNative(
|
|
|
- _private,
|
|
|
- private_key,
|
|
|
- BITS_TO_BYTES(curve->num_n_bits));
|
|
|
+ uECC_vli_bytesToNative(
|
|
|
+ _private,
|
|
|
+ private_key,
|
|
|
+ BITS_TO_BYTES(curve->num_n_bits));
|
|
|
|
|
|
- /* Make sure the private key is in the range [1, n-1]. */
|
|
|
- if (uECC_vli_isZero(_private, BITS_TO_WORDS(curve->num_n_bits))) {
|
|
|
- return 0;
|
|
|
- }
|
|
|
+ /* Make sure the private key is in the range [1, n-1]. */
|
|
|
+ if (uECC_vli_isZero(_private, BITS_TO_WORDS(curve->num_n_bits))) {
|
|
|
+ return 0;
|
|
|
+ }
|
|
|
|
|
|
- if (uECC_vli_cmp(curve->n, _private, BITS_TO_WORDS(curve->num_n_bits)) != 1) {
|
|
|
- return 0;
|
|
|
- }
|
|
|
+ if (uECC_vli_cmp(curve->n, _private, BITS_TO_WORDS(curve->num_n_bits)) != 1) {
|
|
|
+ return 0;
|
|
|
+ }
|
|
|
|
|
|
- /* Compute public key. */
|
|
|
- if (!EccPoint_compute_public_key(_public, _private, curve)) {
|
|
|
- return 0;
|
|
|
- }
|
|
|
+ /* Compute public key. */
|
|
|
+ if (!EccPoint_compute_public_key(_public, _private, curve)) {
|
|
|
+ return 0;
|
|
|
+ }
|
|
|
|
|
|
- uECC_vli_nativeToBytes(public_key, curve->num_bytes, _public);
|
|
|
- uECC_vli_nativeToBytes(
|
|
|
- public_key +
|
|
|
- curve->num_bytes, curve->num_bytes, _public + curve->num_words);
|
|
|
- return 1;
|
|
|
+ uECC_vli_nativeToBytes(public_key, curve->num_bytes, _public);
|
|
|
+ uECC_vli_nativeToBytes(
|
|
|
+ public_key +
|
|
|
+ curve->num_bytes, curve->num_bytes, _public + curve->num_words);
|
|
|
+ return 1;
|
|
|
}
|
lly