diff options
Diffstat (limited to 'lib/chacha.c')
| -rw-r--r-- | lib/chacha.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/lib/chacha.c b/lib/chacha.c index 1bdc688c18df..a46d2832dbab 100644 --- a/lib/chacha.c +++ b/lib/chacha.c @@ -21,7 +21,7 @@ static void chacha_permute(u32 *x, int nrounds) int i; /* whitelist the allowed round counts */ - WARN_ON_ONCE(nrounds != 20); + WARN_ON_ONCE(nrounds != 20 && nrounds != 12); for (i = 0; i < nrounds; i += 2) { x[0] += x[4]; x[12] = rol32(x[12] ^ x[0], 16); @@ -70,7 +70,7 @@ static void chacha_permute(u32 *x, int nrounds) * chacha_block - generate one keystream block and increment block counter * @state: input state matrix (16 32-bit words) * @stream: output keystream block (64 bytes) - * @nrounds: number of rounds (currently must be 20) + * @nrounds: number of rounds (20 or 12; 20 is recommended) * * This is the ChaCha core, a function from 64-byte strings to 64-byte strings. * The caller has already converted the endianness of the input. This function @@ -96,7 +96,7 @@ EXPORT_SYMBOL(chacha_block); * hchacha_block - abbreviated ChaCha core, for XChaCha * @in: input state matrix (16 32-bit words) * @out: output (8 32-bit words) - * @nrounds: number of rounds (currently must be 20) + * @nrounds: number of rounds (20 or 12; 20 is recommended) * * HChaCha is the ChaCha equivalent of HSalsa and is an intermediate step * towards XChaCha (see https://cr.yp.to/snuffle/xsalsa-20081128.pdf). HChaCha |