kris/pqc
1
1
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Made one more cast explicit

Browse Source
This commit is contained in:
Peter Schwabe 2019-02-14 16:18:17 +01:00
parent 393c7a3cde
commit bab1d185cd
1 changed files with 7 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
crypto_kem/kyber768/clean/kem.c
View File

@ -84,25 +84,25 @@ int PQCLEAN_KYBER768_crypto_kem_dec(unsigned char *ss, const unsigned char *ct,
unsigned char cmp[KYBER_CIPHERTEXTBYTES]; unsigned char cmp[KYBER_CIPHERTEXTBYTES];
unsigned char buf[2 * KYBER_SYMBYTES]; unsigned char buf[2 * KYBER_SYMBYTES];
unsigned char unsigned char
kr[2 * KYBER_SYMBYTES]; /* Will contain key, coins, qrom-hash */ kr[2 * KYBER_SYMBYTES]; /* Will contain key, coins, qrom-hash */
const unsigned char *pk = sk + KYBER_INDCPA_SECRETKEYBYTES; const unsigned char *pk = sk + KYBER_INDCPA_SECRETKEYBYTES;
PQCLEAN_KYBER768_indcpa_dec(buf, ct, sk); PQCLEAN_KYBER768_indcpa_dec(buf, ct, sk);
for (i = 0; i < KYBER_SYMBYTES; i++) { /* Multitarget countermeasure for coins + contributory KEM */ for (i = 0; i < KYBER_SYMBYTES; i++) { /* Multitarget countermeasure for coins + contributory KEM */
buf[KYBER_SYMBYTES + i] = sk[KYBER_SECRETKEYBYTES - 2 * KYBER_SYMBYTES + i]; /* Save hash by storing H(pk) in sk */ buf[KYBER_SYMBYTES + i] = sk[KYBER_SECRETKEYBYTES - 2 * KYBER_SYMBYTES + i]; /* Save hash by storing H(pk) in sk */
} }
sha3_512(kr, buf, 2 * KYBER_SYMBYTES); sha3_512(kr, buf, 2 * KYBER_SYMBYTES);
PQCLEAN_KYBER768_indcpa_enc(cmp, buf, pk, kr + KYBER_SYMBYTES); /* coins are in kr+KYBER_SYMBYTES */ PQCLEAN_KYBER768_indcpa_enc(cmp, buf, pk, kr + KYBER_SYMBYTES); /* coins are in kr+KYBER_SYMBYTES */
fail = PQCLEAN_KYBER768_verify(ct, cmp, KYBER_CIPHERTEXTBYTES); fail = PQCLEAN_KYBER768_verify(ct, cmp, KYBER_CIPHERTEXTBYTES);
sha3_256(kr + KYBER_SYMBYTES, ct, KYBER_CIPHERTEXTBYTES); /* overwrite coins in kr with H(c) */ sha3_256(kr + KYBER_SYMBYTES, ct, KYBER_CIPHERTEXTBYTES); /* overwrite coins in kr with H(c) */
PQCLEAN_KYBER768_cmov(kr, sk + KYBER_SECRETKEYBYTES - KYBER_SYMBYTES, KYBER_SYMBYTES, fail); /* Overwrite pre-k with z on re-encryption failure */ PQCLEAN_KYBER768_cmov(kr, sk + KYBER_SECRETKEYBYTES - KYBER_SYMBYTES, KYBER_SYMBYTES, (unsigned char)fail); /* Overwrite pre-k with z on re-encryption failure */
sha3_256(ss, kr, 2 * KYBER_SYMBYTES); /* hash concatenation of pre-k and H(c) to k */ sha3_256(ss, kr, 2 * KYBER_SYMBYTES); /* hash concatenation of pre-k and H(c) to k */
return 0; return 0;
} }