mirror of
https://github.com/oxen-io/lokinet.git
synced 2024-11-19 09:25:28 +00:00
100 lines
2.3 KiB
C
100 lines
2.3 KiB
C
|
|
#include <limits.h>
|
|
#include <stdint.h>
|
|
#include <string.h>
|
|
|
|
#include <sodium/crypto_hash_sha512.h>
|
|
#include <sodium/crypto_sign_ed25519.h>
|
|
#include <sodium/crypto_verify_32.h>
|
|
#include "sign_ed25519_ref10.h"
|
|
#include <sodium/private/ed25519_ref10.h>
|
|
#include <sodium/utils.h>
|
|
|
|
int
|
|
_crypto_sign_ed25519_verify_detached(const unsigned char *sig,
|
|
const unsigned char *m,
|
|
unsigned long long mlen,
|
|
const unsigned char *pk, int prehashed)
|
|
{
|
|
crypto_hash_sha512_state hs;
|
|
unsigned char h[64];
|
|
unsigned char rcheck[32];
|
|
ge25519_p3 A;
|
|
ge25519_p2 R;
|
|
|
|
#ifndef ED25519_COMPAT
|
|
if(sc25519_is_canonical(sig + 32) == 0 || ge25519_has_small_order(sig) != 0)
|
|
{
|
|
return -1;
|
|
}
|
|
if(ge25519_is_canonical(pk) == 0)
|
|
{
|
|
return -1;
|
|
}
|
|
#else
|
|
if(sig[63] & 224)
|
|
{
|
|
return -1;
|
|
}
|
|
#endif
|
|
if(ge25519_has_small_order(pk) != 0
|
|
|| ge25519_frombytes_negate_vartime(&A, pk) != 0)
|
|
{
|
|
return -1;
|
|
}
|
|
_crypto_sign_ed25519_ref10_hinit(&hs, prehashed);
|
|
crypto_hash_sha512_update(&hs, sig, 32);
|
|
crypto_hash_sha512_update(&hs, pk, 32);
|
|
crypto_hash_sha512_update(&hs, m, mlen);
|
|
crypto_hash_sha512_final(&hs, h);
|
|
sc25519_reduce(h);
|
|
|
|
ge25519_double_scalarmult_vartime(&R, h, &A, sig + 32);
|
|
ge25519_tobytes(rcheck, &R);
|
|
|
|
return crypto_verify_32(rcheck, sig) | (-(rcheck == sig))
|
|
| sodium_memcmp(sig, rcheck, 32);
|
|
}
|
|
|
|
int
|
|
crypto_sign_ed25519_verify_detached(const unsigned char *sig,
|
|
const unsigned char *m,
|
|
unsigned long long mlen,
|
|
const unsigned char *pk)
|
|
{
|
|
return _crypto_sign_ed25519_verify_detached(sig, m, mlen, pk, 0);
|
|
}
|
|
|
|
int
|
|
crypto_sign_ed25519_open(unsigned char *m, unsigned long long *mlen_p,
|
|
const unsigned char *sm, unsigned long long smlen,
|
|
const unsigned char *pk)
|
|
{
|
|
unsigned long long mlen;
|
|
|
|
if(smlen < 64 || smlen - 64 > crypto_sign_ed25519_MESSAGEBYTES_MAX)
|
|
{
|
|
goto badsig;
|
|
}
|
|
mlen = smlen - 64;
|
|
if(crypto_sign_ed25519_verify_detached(sm, sm + 64, mlen, pk) != 0)
|
|
{
|
|
memset(m, 0, mlen);
|
|
goto badsig;
|
|
}
|
|
if(mlen_p != NULL)
|
|
{
|
|
*mlen_p = mlen;
|
|
}
|
|
memmove(m, sm + 64, mlen);
|
|
|
|
return 0;
|
|
|
|
badsig:
|
|
if(mlen_p != NULL)
|
|
{
|
|
*mlen_p = 0;
|
|
}
|
|
return -1;
|
|
}
|