diff options
Diffstat (limited to 'src/verify.c')
-rw-r--r-- | src/verify.c | 77 |
1 files changed, 0 insertions, 77 deletions
diff --git a/src/verify.c b/src/verify.c deleted file mode 100644 index 32f988e..0000000 --- a/src/verify.c +++ /dev/null @@ -1,77 +0,0 @@ -#include "ed25519.h" -#include "sha512.h" -#include "ge.h" -#include "sc.h" - -static int consttime_equal(const unsigned char *x, const unsigned char *y) { - unsigned char r = 0; - - r = x[0] ^ y[0]; - #define F(i) r |= x[i] ^ y[i] - F(1); - F(2); - F(3); - F(4); - F(5); - F(6); - F(7); - F(8); - F(9); - F(10); - F(11); - F(12); - F(13); - F(14); - F(15); - F(16); - F(17); - F(18); - F(19); - F(20); - F(21); - F(22); - F(23); - F(24); - F(25); - F(26); - F(27); - F(28); - F(29); - F(30); - F(31); - #undef F - - return !r; -} - -int ed25519_verify(const unsigned char *signature, const unsigned char *message, size_t message_len, const unsigned char *public_key) { - unsigned char h[64]; - unsigned char checker[32]; - sha512_context hash; - ge_p3 A; - ge_p2 R; - - if (signature[63] & 224) { - return 0; - } - - if (ge_frombytes_negate_vartime(&A, public_key) != 0) { - return 0; - } - - sha512_init(&hash); - sha512_update(&hash, signature, 32); - sha512_update(&hash, public_key, 32); - sha512_update(&hash, message, message_len); - sha512_final(&hash, h); - - sc_reduce(h); - ge_double_scalarmult_vartime(&R, h, &A, signature + 32); - ge_tobytes(checker, &R); - - if (!consttime_equal(checker, signature)) { - return 0; - } - - return 1; -} |