From: Eric Biggers <ebiggers@xxxxxxxxxx> Now that the generic implementation of ChaCha20 has been refactored to allow varying the number of rounds, add support for XChaCha12, which is the XSalsa construction applied to ChaCha12. ChaCha12 is one of the three ciphers specified by the original ChaCha paper (https://cr.yp.to/chacha/chacha-20080128.pdf: "ChaCha, a variant of Salsa20"), alongside ChaCha8 and ChaCha20. ChaCha12 is faster than ChaCha20 but has a lower, but still large, security margin. We need XChaCha12 support so that it can be used in the Adiantum encryption mode, which enables disk/file encryption on low-end mobile devices where AES-XTS is too slow as the CPUs lack AES instructions. We'd prefer XChaCha20 (the more popular variant), but it's too slow on some of our target devices, so at least in some cases we do need the XChaCha12-based version. In more detail, the problem is that Adiantum is still much slower than we're happy with, and encryption still has a quite noticeable effect on the feel of low-end devices. Users and vendors push back hard against encryption that degrades the user experience, which always risks encryption being disabled entirely. So we need to choose the fastest option that gives us a solid margin of security, and here that's XChaCha12. The best known attack on ChaCha breaks only 7 rounds and has 2^235 time complexity, so ChaCha12's security margin is still better than AES-256's. Much has been learned about cryptanalysis of ARX ciphers since Salsa20 was originally designed in 2005, and it now seems we can be comfortable with a smaller number of rounds. The eSTREAM project also suggests the 12-round version of Salsa20 as providing the best balance among the different variants: combining very good performance with a "comfortable margin of security". Note that it would be trivial to add vanilla ChaCha12 in addition to XChaCha12. However, it's unneeded for now and therefore is omitted. As discussed in the patch that introduced XChaCha20 support, I considered splitting the code into separate chacha-common, chacha20, xchacha20, and xchacha12 modules, so that these algorithms could be enabled/disabled independently. However, since nearly all the code is shared anyway, I ultimately decided there would have been little benefit to the added complexity. Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx> --- crypto/Kconfig | 8 +- crypto/chacha_generic.c | 26 +- crypto/testmgr.c | 6 + crypto/testmgr.h | 578 ++++++++++++++++++++++++++++++++++++++++ include/crypto/chacha.h | 7 + lib/chacha.c | 6 +- 6 files changed, 625 insertions(+), 6 deletions(-) diff --git a/crypto/Kconfig b/crypto/Kconfig index d9acbce23d4d5..4fa0a4a0e8615 100644 --- a/crypto/Kconfig +++ b/crypto/Kconfig @@ -1387,10 +1387,10 @@ config CRYPTO_SALSA20 Bernstein <djb@xxxxxxxx>. See <http://cr.yp.to/snuffle.html> config CRYPTO_CHACHA20 - tristate "ChaCha20 stream cipher algorithms" + tristate "ChaCha stream cipher algorithms" select CRYPTO_BLKCIPHER help - The ChaCha20 and XChaCha20 stream cipher algorithms. + The ChaCha20, XChaCha20, and XChaCha12 stream cipher algorithms. ChaCha20 is a 256-bit high-speed stream cipher designed by Daniel J. Bernstein and further specified in RFC7539 for use in IETF protocols. @@ -1403,6 +1403,10 @@ config CRYPTO_CHACHA20 while provably retaining ChaCha20's security. See also: <https://cr.yp.to/snuffle/xsalsa-20081128.pdf> + XChaCha12 is XChaCha20 reduced to 12 rounds, with correspondingly + reduced security margin but increased performance. It can be needed + in some performance-sensitive scenarios. + config CRYPTO_CHACHA20_X86_64 tristate "ChaCha20 cipher algorithm (x86_64/SSSE3/AVX2)" depends on X86 && 64BIT diff --git a/crypto/chacha_generic.c b/crypto/chacha_generic.c index 8e25e9930c549..8f8f84e51f334 100644 --- a/crypto/chacha_generic.c +++ b/crypto/chacha_generic.c @@ -1,5 +1,5 @@ /* - * ChaCha20 (RFC7539) and XChaCha20 stream cipher algorithms + * ChaCha and XChaCha stream ciphers, including ChaCha20 (RFC7539) * * Copyright (C) 2015 Martin Willi * Copyright (C) 2018 Google LLC @@ -106,6 +106,13 @@ int crypto_chacha20_setkey(struct crypto_skcipher *tfm, const u8 *key, } EXPORT_SYMBOL_GPL(crypto_chacha20_setkey); +int crypto_chacha12_setkey(struct crypto_skcipher *tfm, const u8 *key, + unsigned int keysize) +{ + return chacha_setkey(tfm, key, keysize, 12); +} +EXPORT_SYMBOL_GPL(crypto_chacha12_setkey); + int crypto_chacha_crypt(struct skcipher_request *req) { struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); @@ -168,6 +175,21 @@ static struct skcipher_alg algs[] = { .setkey = crypto_chacha20_setkey, .encrypt = crypto_xchacha_crypt, .decrypt = crypto_xchacha_crypt, + }, { + .base.cra_name = "xchacha12", + .base.cra_driver_name = "xchacha12-generic", + .base.cra_priority = 100, + .base.cra_blocksize = 1, + .base.cra_ctxsize = sizeof(struct chacha_ctx), + .base.cra_module = THIS_MODULE, + + .min_keysize = CHACHA_KEY_SIZE, + .max_keysize = CHACHA_KEY_SIZE, + .ivsize = XCHACHA_IV_SIZE, + .chunksize = CHACHA_BLOCK_SIZE, + .setkey = crypto_chacha12_setkey, + .encrypt = crypto_xchacha_crypt, + .decrypt = crypto_xchacha_crypt, } }; @@ -191,3 +213,5 @@ MODULE_ALIAS_CRYPTO("chacha20"); MODULE_ALIAS_CRYPTO("chacha20-generic"); MODULE_ALIAS_CRYPTO("xchacha20"); MODULE_ALIAS_CRYPTO("xchacha20-generic"); +MODULE_ALIAS_CRYPTO("xchacha12"); +MODULE_ALIAS_CRYPTO("xchacha12-generic"); diff --git a/crypto/testmgr.c b/crypto/testmgr.c index a5512e69c8f31..3ff70ebc745cb 100644 --- a/crypto/testmgr.c +++ b/crypto/testmgr.c @@ -3544,6 +3544,12 @@ static const struct alg_test_desc alg_test_descs[] = { .suite = { .hash = __VECS(aes_xcbc128_tv_template) } + }, { + .alg = "xchacha12", + .test = alg_test_skcipher, + .suite = { + .cipher = __VECS(xchacha12_tv_template) + }, }, { .alg = "xchacha20", .test = alg_test_skcipher, diff --git a/crypto/testmgr.h b/crypto/testmgr.h index 371641c73cf8c..3b57b2701fcb2 100644 --- a/crypto/testmgr.h +++ b/crypto/testmgr.h @@ -31379,6 +31379,584 @@ static const struct cipher_testvec xchacha20_tv_template[] = { }, }; +/* + * Same as XChaCha20 test vectors above, but recomputed the ciphertext with + * XChaCha12, using a modified libsodium. + */ +static const struct cipher_testvec xchacha12_tv_template[] = { + { + .key = "\x79\xc9\x97\x98\xac\x67\x30\x0b" + "\xbb\x27\x04\xc9\x5c\x34\x1e\x32" + "\x45\xf3\xdc\xb2\x17\x61\xb9\x8e" + "\x52\xff\x45\xb2\x4f\x30\x4f\xc4", + .klen = 32, + .iv = "\xb3\x3f\xfd\x30\x96\x47\x9b\xcf" + "\xbc\x9a\xee\x49\x41\x76\x88\xa0" + "\xa2\x55\x4f\x8d\x95\x38\x94\x19" + "\x00\x00\x00\x00\x00\x00\x00\x00", + .ptext = "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00", + .ctext = "\x1b\x78\x7f\xd7\xa1\x41\x68\xab" + "\x3d\x3f\xd1\x7b\x69\x56\xb2\xd5" + "\x43\xce\xeb\xaf\x36\xf0\x29\x9d" + "\x3a\xfb\x18\xae\x1b", + .len = 29, + }, { + .key = "\x9d\x23\xbd\x41\x49\xcb\x97\x9c" + "\xcf\x3c\x5c\x94\xdd\x21\x7e\x98" + "\x08\xcb\x0e\x50\xcd\x0f\x67\x81" + "\x22\x35\xea\xaf\x60\x1d\x62\x32", + .klen = 32, + .iv = "\xc0\x47\x54\x82\x66\xb7\xc3\x70" + "\xd3\x35\x66\xa2\x42\x5c\xbf\x30" + "\xd8\x2d\x1e\xaf\x52\x94\x10\x9e" + "\x00\x00\x00\x00\x00\x00\x00\x00", + .ptext = "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00", + .ctext = "\xfb\x32\x09\x1d\x83\x05\xae\x4c" + "\x13\x1f\x12\x71\xf2\xca\xb2\xeb" + "\x5b\x83\x14\x7d\x83\xf6\x57\x77" + "\x2e\x40\x1f\x92\x2c\xf9\xec\x35" + "\x34\x1f\x93\xdf\xfb\x30\xd7\x35" + "\x03\x05\x78\xc1\x20\x3b\x7a\xe3" + "\x62\xa3\x89\xdc\x11\x11\x45\xa8" + "\x82\x89\xa0\xf1\x4e\xc7\x0f\x11" + "\x69\xdd\x0c\x84\x2b\x89\x5c\xdc" + "\xf0\xde\x01\xef\xc5\x65\x79\x23" + "\x87\x67\xd6\x50\xd9\x8d\xd9\x92" + "\x54\x5b\x0e", + .len = 91, + }, { + .key = "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00", + .klen = 32, + .iv = "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x67\xc6\x69\x73" + "\x51\xff\x4a\xec\x29\xcd\xba\xab" + "\x00\x00\x00\x00\x00\x00\x00\x00", + .ptext = "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00", + .ctext = "\xdf\x2d\xc6\x21\x2a\x9d\xa1\xbb" + "\xc2\x77\x66\x0c\x5c\x46\xef\xa7" + "\x79\x1b\xb9\xdf\x55\xe2\xf9\x61" + "\x4c\x7b\xa4\x52\x24\xaf\xa2\xda" + "\xd1\x8f\x8f\xa2\x9e\x53\x4d\xc4" + "\xb8\x55\x98\x08\x7c\x08\xd4\x18" + "\x67\x8f\xef\x50\xb1\x5f\xa5\x77" + "\x4c\x25\xe7\x86\x26\x42\xca\x44", + .len = 64, + }, { + .key = "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x00\x00\x00\x00\x01", + .klen = 32, + .iv = "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x02\xf2\xfb\xe3\x46" + "\x7c\xc2\x54\xf8\x1b\xe8\xe7\x8d" + "\x01\x00\x00\x00\x00\x00\x00\x00", + .ptext = "\x41\x6e\x79\x20\x73\x75\x62\x6d" + "\x69\x73\x73\x69\x6f\x6e\x20\x74" + "\x6f\x20\x74\x68\x65\x20\x49\x45" + "\x54\x46\x20\x69\x6e\x74\x65\x6e" + "\x64\x65\x64\x20\x62\x79\x20\x74" + "\x68\x65\x20\x43\x6f\x6e\x74\x72" + "\x69\x62\x75\x74\x6f\x72\x20\x66" + "\x6f\x72\x20\x70\x75\x62\x6c\x69" + "\x63\x61\x74\x69\x6f\x6e\x20\x61" + "\x73\x20\x61\x6c\x6c\x20\x6f\x72" + "\x20\x70\x61\x72\x74\x20\x6f\x66" + "\x20\x61\x6e\x20\x49\x45\x54\x46" + "\x20\x49\x6e\x74\x65\x72\x6e\x65" + "\x74\x2d\x44\x72\x61\x66\x74\x20" + "\x6f\x72\x20\x52\x46\x43\x20\x61" + "\x6e\x64\x20\x61\x6e\x79\x20\x73" + "\x74\x61\x74\x65\x6d\x65\x6e\x74" + "\x20\x6d\x61\x64\x65\x20\x77\x69" + "\x74\x68\x69\x6e\x20\x74\x68\x65" + "\x20\x63\x6f\x6e\x74\x65\x78\x74" + "\x20\x6f\x66\x20\x61\x6e\x20\x49" + "\x45\x54\x46\x20\x61\x63\x74\x69" + "\x76\x69\x74\x79\x20\x69\x73\x20" + "\x63\x6f\x6e\x73\x69\x64\x65\x72" + "\x65\x64\x20\x61\x6e\x20\x22\x49" + "\x45\x54\x46\x20\x43\x6f\x6e\x74" + "\x72\x69\x62\x75\x74\x69\x6f\x6e" + "\x22\x2e\x20\x53\x75\x63\x68\x20" + "\x73\x74\x61\x74\x65\x6d\x65\x6e" + "\x74\x73\x20\x69\x6e\x63\x6c\x75" + "\x64\x65\x20\x6f\x72\x61\x6c\x20" + "\x73\x74\x61\x74\x65\x6d\x65\x6e" + "\x74\x73\x20\x69\x6e\x20\x49\x45" + "\x54\x46\x20\x73\x65\x73\x73\x69" + "\x6f\x6e\x73\x2c\x20\x61\x73\x20" + "\x77\x65\x6c\x6c\x20\x61\x73\x20" + "\x77\x72\x69\x74\x74\x65\x6e\x20" + "\x61\x6e\x64\x20\x65\x6c\x65\x63" + "\x74\x72\x6f\x6e\x69\x63\x20\x63" + "\x6f\x6d\x6d\x75\x6e\x69\x63\x61" + "\x74\x69\x6f\x6e\x73\x20\x6d\x61" + "\x64\x65\x20\x61\x74\x20\x61\x6e" + "\x79\x20\x74\x69\x6d\x65\x20\x6f" + "\x72\x20\x70\x6c\x61\x63\x65\x2c" + "\x20\x77\x68\x69\x63\x68\x20\x61" + "\x72\x65\x20\x61\x64\x64\x72\x65" + "\x73\x73\x65\x64\x20\x74\x6f", + .ctext = "\xe4\xa6\xc8\x30\xc4\x23\x13\xd6" + "\x08\x4d\xc9\xb7\xa5\x64\x7c\xb9" + "\x71\xe2\xab\x3e\xa8\x30\x8a\x1c" + "\x4a\x94\x6d\x9b\xe0\xb3\x6f\xf1" + "\xdc\xe3\x1b\xb3\xa9\x6d\x0d\xd6" + "\xd0\xca\x12\xef\xe7\x5f\xd8\x61" + "\x3c\x82\xd3\x99\x86\x3c\x6f\x66" + "\x02\x06\xdc\x55\xf9\xed\xdf\x38" + "\xb4\xa6\x17\x00\x7f\xef\xbf\x4f" + "\xf8\x36\xf1\x60\x7e\x47\xaf\xdb" + "\x55\x9b\x12\xcb\x56\x44\xa7\x1f" + "\xd3\x1a\x07\x3b\x00\xec\xe6\x4c" + "\xa2\x43\x27\xdf\x86\x19\x4f\x16" + "\xed\xf9\x4a\xf3\x63\x6f\xfa\x7f" + "\x78\x11\xf6\x7d\x97\x6f\xec\x6f" + "\x85\x0f\x5c\x36\x13\x8d\x87\xe0" + "\x80\xb1\x69\x0b\x98\x89\x9c\x4e" + "\xf8\xdd\xee\x5c\x0a\x85\xce\xd4" + "\xea\x1b\x48\xbe\x08\xf8\xe2\xa8" + "\xa5\xb0\x3c\x79\xb1\x15\xb4\xb9" + "\x75\x10\x95\x35\x81\x7e\x26\xe6" + "\x78\xa4\x88\xcf\xdb\x91\x34\x18" + "\xad\xd7\x8e\x07\x7d\xab\x39\xf9" + "\xa3\x9e\xa5\x1d\xbb\xed\x61\xfd" + "\xdc\xb7\x5a\x27\xfc\xb5\xc9\x10" + "\xa8\xcc\x52\x7f\x14\x76\x90\xe7" + "\x1b\x29\x60\x74\xc0\x98\x77\xbb" + "\xe0\x54\xbb\x27\x49\x59\x1e\x62" + "\x3d\xaf\x74\x06\xa4\x42\x6f\xc6" + "\x52\x97\xc4\x1d\xc4\x9f\xe2\xe5" + "\x38\x57\x91\xd1\xa2\x28\xcc\x40" + "\xcc\x70\x59\x37\xfc\x9f\x4b\xda" + "\xa0\xeb\x97\x9a\x7d\xed\x14\x5c" + "\x9c\xb7\x93\x26\x41\xa8\x66\xdd" + "\x87\x6a\xc0\xd3\xc2\xa9\x3e\xae" + "\xe9\x72\xfe\xd1\xb3\xac\x38\xea" + "\x4d\x15\xa9\xd5\x36\x61\xe9\x96" + "\x6c\x23\xf8\x43\xe4\x92\x29\xd9" + "\x8b\x78\xf7\x0a\x52\xe0\x19\x5b" + "\x59\x69\x5b\x5d\xa1\x53\xc4\x68" + "\xe1\xbb\xac\x89\x14\xe2\xe2\x85" + "\x41\x18\xf5\xb3\xd1\xfa\x68\x19" + "\x44\x78\xdc\xcf\xe7\x88\x2d\x52" + "\x5f\x40\xb5\x7e\xf8\x88\xa2\xae" + "\x4a\xb2\x07\x35\x9d\x9b\x07\x88" + "\xb7\x00\xd0\x0c\xb6\xa0\x47\x59" + "\xda\x4e\xc9\xab\x9b\x8a\x7b", + + .len = 375, + .also_non_np = 1, + .np = 3, + .tap = { 375 - 20, 4, 16 }, + + }, { + .key = "\x1c\x92\x40\xa5\xeb\x55\xd3\x8a" + "\xf3\x33\x88\x86\x04\xf6\xb5\xf0" + "\x47\x39\x17\xc1\x40\x2b\x80\x09" + "\x9d\xca\x5c\xbc\x20\x70\x75\xc0", + .klen = 32, + .iv = "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x02\x76\x5a\x2e\x63" + "\x33\x9f\xc9\x9a\x66\x32\x0d\xb7" + "\x2a\x00\x00\x00\x00\x00\x00\x00", + .ptext = "\x27\x54\x77\x61\x73\x20\x62\x72" + "\x69\x6c\x6c\x69\x67\x2c\x20\x61" + "\x6e\x64\x20\x74\x68\x65\x20\x73" + "\x6c\x69\x74\x68\x79\x20\x74\x6f" + "\x76\x65\x73\x0a\x44\x69\x64\x20" + "\x67\x79\x72\x65\x20\x61\x6e\x64" + "\x20\x67\x69\x6d\x62\x6c\x65\x20" + "\x69\x6e\x20\x74\x68\x65\x20\x77" + "\x61\x62\x65\x3a\x0a\x41\x6c\x6c" + "\x20\x6d\x69\x6d\x73\x79\x20\x77" + "\x65\x72\x65\x20\x74\x68\x65\x20" + "\x62\x6f\x72\x6f\x67\x6f\x76\x65" + "\x73\x2c\x0a\x41\x6e\x64\x20\x74" + "\x68\x65\x20\x6d\x6f\x6d\x65\x20" + "\x72\x61\x74\x68\x73\x20\x6f\x75" + "\x74\x67\x72\x61\x62\x65\x2e", + .ctext = "\xb9\x68\xbc\x6a\x24\xbc\xcc\xd8" + "\x9b\x2a\x8d\x5b\x96\xaf\x56\xe3" + "\x11\x61\xe7\xa7\x9b\xce\x4e\x7d" + "\x60\x02\x48\xac\xeb\xd5\x3a\x26" + "\x9d\x77\x3b\xb5\x32\x13\x86\x8e" + "\x20\x82\x26\x72\xae\x64\x1b\x7e" + "\x2e\x01\x68\xb4\x87\x45\xa1\x24" + "\xe4\x48\x40\xf0\xaa\xac\xee\xa9" + "\xfc\x31\xad\x9d\x89\xa3\xbb\xd2" + "\xe4\x25\x13\xad\x0f\x5e\xdf\x3c" + "\x27\xab\xb8\x62\x46\x22\x30\x48" + "\x55\x2c\x4e\x84\x78\x1d\x0d\x34" + "\x8d\x3c\x91\x0a\x7f\x5b\x19\x9f" + "\x97\x05\x4c\xa7\x62\x47\x8b\xc5" + "\x44\x2e\x20\x33\xdd\xa0\x82\xa9" + "\x25\x76\x37\xe6\x3c\x67\x5b", + .len = 127, + }, { + .key = "\x1c\x92\x40\xa5\xeb\x55\xd3\x8a" + "\xf3\x33\x88\x86\x04\xf6\xb5\xf0" + "\x47\x39\x17\xc1\x40\x2b\x80\x09" + "\x9d\xca\x5c\xbc\x20\x70\x75\xc0", + .klen = 32, + .iv = "\x00\x00\x00\x00\x00\x00\x00\x00" + "\x00\x00\x00\x01\x31\x58\xa3\x5a" + "\x25\x5d\x05\x17\x58\xe9\x5e\xd4" + "\x1c\x00\x00\x00\x00\x00\x00\x00", + .ptext = "\x49\xee\xe0\xdc\x24\x90\x40\xcd" + "\xc5\x40\x8f\x47\x05\xbc\xdd\x81" + "\x47\xc6\x8d\xe6\xb1\x8f\xd7\xcb" + "\x09\x0e\x6e\x22\x48\x1f\xbf\xb8" + "\x5c\xf7\x1e\x8a\xc1\x23\xf2\xd4" + "\x19\x4b\x01\x0f\x4e\xa4\x43\xce" + "\x01\xc6\x67\xda\x03\x91\x18\x90" + "\xa5\xa4\x8e\x45\x03\xb3\x2d\xac" + "\x74\x92\xd3\x53\x47\xc8\xdd\x25" + "\x53\x6c\x02\x03\x87\x0d\x11\x0c" + "\x58\xe3\x12\x18\xfd\x2a\x5b\x40" + "\x0c\x30\xf0\xb8\x3f\x43\xce\xae" + "\x65\x3a\x7d\x7c\xf4\x54\xaa\xcc" + "\x33\x97\xc3\x77\xba\xc5\x70\xde" + "\xd7\xd5\x13\xa5\x65\xc4\x5f\x0f" + "\x46\x1a\x0d\x97\xb5\xf3\xbb\x3c" + "\x84\x0f\x2b\xc5\xaa\xea\xf2\x6c" + "\xc9\xb5\x0c\xee\x15\xf3\x7d\xbe" + "\x9f\x7b\x5a\xa6\xae\x4f\x83\xb6" + "\x79\x49\x41\xf4\x58\x18\xcb\x86" + "\x7f\x30\x0e\xf8\x7d\x44\x36\xea" + "\x75\xeb\x88\x84\x40\x3c\xad\x4f" + "\x6f\x31\x6b\xaa\x5d\xe5\xa5\xc5" + "\x21\x66\xe9\xa7\xe3\xb2\x15\x88" + "\x78\xf6\x79\xa1\x59\x47\x12\x4e" + "\x9f\x9f\x64\x1a\xa0\x22\x5b\x08" + "\xbe\x7c\x36\xc2\x2b\x66\x33\x1b" + "\xdd\x60\x71\xf7\x47\x8c\x61\xc3" + "\xda\x8a\x78\x1e\x16\xfa\x1e\x86" + "\x81\xa6\x17\x2a\xa7\xb5\xc2\xe7" + "\xa4\xc7\x42\xf1\xcf\x6a\xca\xb4" + "\x45\xcf\xf3\x93\xf0\xe7\xea\xf6" + "\xf4\xe6\x33\x43\x84\x93\xa5\x67" + "\x9b\x16\x58\x58\x80\x0f\x2b\x5c" + "\x24\x74\x75\x7f\x95\x81\xb7\x30" + "\x7a\x33\xa7\xf7\x94\x87\x32\x27" + "\x10\x5d\x14\x4c\x43\x29\xdd\x26" + "\xbd\x3e\x3c\x0e\xfe\x0e\xa5\x10" + "\xea\x6b\x64\xfd\x73\xc6\xed\xec" + "\xa8\xc9\xbf\xb3\xba\x0b\x4d\x07" + "\x70\xfc\x16\xfd\x79\x1e\xd7\xc5" + "\x49\x4e\x1c\x8b\x8d\x79\x1b\xb1" + "\xec\xca\x60\x09\x4c\x6a\xd5\x09" + "\x49\x46\x00\x88\x22\x8d\xce\xea" + "\xb1\x17\x11\xde\x42\xd2\x23\xc1" + "\x72\x11\xf5\x50\x73\x04\x40\x47" + "\xf9\x5d\xe7\xa7\x26\xb1\x7e\xb0" + "\x3f\x58\xc1\x52\xab\x12\x67\x9d" + "\x3f\x43\x4b\x68\xd4\x9c\x68\x38" + "\x07\x8a\x2d\x3e\xf3\xaf\x6a\x4b" + "\xf9\xe5\x31\x69\x22\xf9\xa6\x69" + "\xc6\x9c\x96\x9a\x12\x35\x95\x1d" + "\x95\xd5\xdd\xbe\xbf\x93\x53\x24" + "\xfd\xeb\xc2\x0a\x64\xb0\x77\x00" + "\x6f\x88\xc4\x37\x18\x69\x7c\xd7" + "\x41\x92\x55\x4c\x03\xa1\x9a\x4b" + "\x15\xe5\xdf\x7f\x37\x33\x72\xc1" + "\x8b\x10\x67\xa3\x01\x57\x94\x25" + "\x7b\x38\x71\x7e\xdd\x1e\xcc\x73" + "\x55\xd2\x8e\xeb\x07\xdd\xf1\xda" + "\x58\xb1\x47\x90\xfe\x42\x21\x72" + "\xa3\x54\x7a\xa0\x40\xec\x9f\xdd" + "\xc6\x84\x6e\xca\xae\xe3\x68\xb4" + "\x9d\xe4\x78\xff\x57\xf2\xf8\x1b" + "\x03\xa1\x31\xd9\xde\x8d\xf5\x22" + "\x9c\xdd\x20\xa4\x1e\x27\xb1\x76" + "\x4f\x44\x55\xe2\x9b\xa1\x9c\xfe" + "\x54\xf7\x27\x1b\xf4\xde\x02\xf5" + "\x1b\x55\x48\x5c\xdc\x21\x4b\x9e" + "\x4b\x6e\xed\x46\x23\xdc\x65\xb2" + "\xcf\x79\x5f\x28\xe0\x9e\x8b\xe7" + "\x4c\x9d\x8a\xff\xc1\xa6\x28\xb8" + "\x65\x69\x8a\x45\x29\xef\x74\x85" + "\xde\x79\xc7\x08\xae\x30\xb0\xf4" + "\xa3\x1d\x51\x41\xab\xce\xcb\xf6" + "\xb5\xd8\x6d\xe0\x85\xe1\x98\xb3" + "\x43\xbb\x86\x83\x0a\xa0\xf5\xb7" + "\x04\x0b\xfa\x71\x1f\xb0\xf6\xd9" + "\x13\x00\x15\xf0\xc7\xeb\x0d\x5a" + "\x9f\xd7\xb9\x6c\x65\x14\x22\x45" + "\x6e\x45\x32\x3e\x7e\x60\x1a\x12" + "\x97\x82\x14\xfb\xaa\x04\x22\xfa" + "\xa0\xe5\x7e\x8c\x78\x02\x48\x5d" + "\x78\x33\x5a\x7c\xad\xdb\x29\xce" + "\xbb\x8b\x61\xa4\xb7\x42\xe2\xac" + "\x8b\x1a\xd9\x2f\x0b\x8b\x62\x21" + "\x83\x35\x7e\xad\x73\xc2\xb5\x6c" + "\x10\x26\x38\x07\xe5\xc7\x36\x80" + "\xe2\x23\x12\x61\xf5\x48\x4b\x2b" + "\xc5\xdf\x15\xd9\x87\x01\xaa\xac" + "\x1e\x7c\xad\x73\x78\x18\x63\xe0" + "\x8b\x9f\x81\xd8\x12\x6a\x28\x10" + "\xbe\x04\x68\x8a\x09\x7c\x1b\x1c" + "\x83\x66\x80\x47\x80\xe8\xfd\x35" + "\x1c\x97\x6f\xae\x49\x10\x66\xcc" + "\xc6\xd8\xcc\x3a\x84\x91\x20\x77" + "\x72\xe4\x24\xd2\x37\x9f\xc5\xc9" + "\x25\x94\x10\x5f\x40\x00\x64\x99" + "\xdc\xae\xd7\x21\x09\x78\x50\x15" + "\xac\x5f\xc6\x2c\xa2\x0b\xa9\x39" + "\x87\x6e\x6d\xab\xde\x08\x51\x16" + "\xc7\x13\xe9\xea\xed\x06\x8e\x2c" + "\xf8\x37\x8c\xf0\xa6\x96\x8d\x43" + "\xb6\x98\x37\xb2\x43\xed\xde\xdf" + "\x89\x1a\xe7\xeb\x9d\xa1\x7b\x0b" + "\x77\xb0\xe2\x75\xc0\xf1\x98\xd9" + "\x80\x55\xc9\x34\x91\xd1\x59\xe8" + "\x4b\x0f\xc1\xa9\x4b\x7a\x84\x06" + "\x20\xa8\x5d\xfa\xd1\xde\x70\x56" + "\x2f\x9e\x91\x9c\x20\xb3\x24\xd8" + "\x84\x3d\xe1\x8c\x7e\x62\x52\xe5" + "\x44\x4b\x9f\xc2\x93\x03\xea\x2b" + "\x59\xc5\xfa\x3f\x91\x2b\xbb\x23" + "\xf5\xb2\x7b\xf5\x38\xaf\xb3\xee" + "\x63\xdc\x7b\xd1\xff\xaa\x8b\xab" + "\x82\x6b\x37\x04\xeb\x74\xbe\x79" + "\xb9\x83\x90\xef\x20\x59\x46\xff" + "\xe9\x97\x3e\x2f\xee\xb6\x64\x18" + "\x38\x4c\x7a\x4a\xf9\x61\xe8\x9a" + "\xa1\xb5\x01\xa6\x47\xd3\x11\xd4" + "\xce\xd3\x91\x49\x88\xc7\xb8\x4d" + "\xb1\xb9\x07\x6d\x16\x72\xae\x46" + "\x5e\x03\xa1\x4b\xb6\x02\x30\xa8" + "\x3d\xa9\x07\x2a\x7c\x19\xe7\x62" + "\x87\xe3\x82\x2f\x6f\xe1\x09\xd9" + "\x94\x97\xea\xdd\x58\x9e\xae\x76" + "\x7e\x35\xe5\xb4\xda\x7e\xf4\xde" + "\xf7\x32\x87\xcd\x93\xbf\x11\x56" + "\x11\xbe\x08\x74\xe1\x69\xad\xe2" + "\xd7\xf8\x86\x75\x8a\x3c\xa4\xbe" + "\x70\xa7\x1b\xfc\x0b\x44\x2a\x76" + "\x35\xea\x5d\x85\x81\xaf\x85\xeb" + "\xa0\x1c\x61\xc2\xf7\x4f\xa5\xdc" + "\x02\x7f\xf6\x95\x40\x6e\x8a\x9a" + "\xf3\x5d\x25\x6e\x14\x3a\x22\xc9" + "\x37\x1c\xeb\x46\x54\x3f\xa5\x91" + "\xc2\xb5\x8c\xfe\x53\x08\x97\x32" + "\x1b\xb2\x30\x27\xfe\x25\x5d\xdc" + "\x08\x87\xd0\xe5\x94\x1a\xd4\xf1" + "\xfe\xd6\xb4\xa3\xe6\x74\x81\x3c" + "\x1b\xb7\x31\xa7\x22\xfd\xd4\xdd" + "\x20\x4e\x7c\x51\xb0\x60\x73\xb8" + "\x9c\xac\x91\x90\x7e\x01\xb0\xe1" + "\x8a\x2f\x75\x1c\x53\x2a\x98\x2a" + "\x06\x52\x95\x52\xb2\xe9\x25\x2e" + "\x4c\xe2\x5a\x00\xb2\x13\x81\x03" + "\x77\x66\x0d\xa5\x99\xda\x4e\x8c" + "\xac\xf3\x13\x53\x27\x45\xaf\x64" + "\x46\xdc\xea\x23\xda\x97\xd1\xab" + "\x7d\x6c\x30\x96\x1f\xbc\x06\x34" + "\x18\x0b\x5e\x21\x35\x11\x8d\x4c" + "\xe0\x2d\xe9\x50\x16\x74\x81\xa8" + "\xb4\x34\xb9\x72\x42\xa6\xcc\xbc" + "\xca\x34\x83\x27\x10\x5b\x68\x45" + "\x8f\x52\x22\x0c\x55\x3d\x29\x7c" + "\xe3\xc0\x66\x05\x42\x91\x5f\x58" + "\xfe\x4a\x62\xd9\x8c\xa9\x04\x19" + "\x04\xa9\x08\x4b\x57\xfc\x67\x53" + "\x08\x7c\xbc\x66\x8a\xb0\xb6\x9f" + "\x92\xd6\x41\x7c\x5b\x2a\x00\x79" + "\x72", + .ctext = "\xe1\xb6\x8b\x5c\x80\xb8\xcc\x08" + "\x1b\x84\xb2\xd1\xad\xa4\x70\xac" + "\x67\xa9\x39\x27\xac\xb4\x5b\xb7" + "\x4c\x26\x77\x23\x1d\xce\x0a\xbe" + "\x18\x9e\x42\x8b\xbd\x7f\xd6\xf1" + "\xf1\x6b\xe2\x6d\x7f\x92\x0e\xcb" + "\xb8\x79\xba\xb4\xac\x7e\x2d\xc0" + "\x9e\x83\x81\x91\xd5\xea\xc3\x12" + "\x8d\xa4\x26\x70\xa4\xf9\x71\x0b" + "\xbd\x2e\xe1\xb3\x80\x42\x25\xb3" + "\x0b\x31\x99\xe1\x0d\xde\xa6\x90" + "\xf2\xa3\x10\xf7\xe5\xf3\x83\x1e" + "\x2c\xfb\x4d\xf0\x45\x3d\x28\x3c" + "\xb8\xf1\xcb\xbf\x67\xd8\x43\x5a" + "\x9d\x7b\x73\x29\x88\x0f\x13\x06" + "\x37\x50\x0d\x7c\xe6\x9b\x07\xdd" + "\x7e\x01\x1f\x81\x90\x10\x69\xdb" + "\xa4\xad\x8a\x5e\xac\x30\x72\xf2" + "\x36\xcd\xe3\x23\x49\x02\x93\xfa" + "\x3d\xbb\xe2\x98\x83\xeb\xe9\x8d" + "\xb3\x8f\x11\xaa\x53\xdb\xaf\x2e" + "\x95\x13\x99\x3d\x71\xbd\x32\x92" + "\xdd\xfc\x9d\x5e\x6f\x63\x2c\xee" + "\x91\x1f\x4c\x64\x3d\x87\x55\x0f" + "\xcc\x3d\x89\x61\x53\x02\x57\x8f" + "\xe4\x77\x29\x32\xaf\xa6\x2f\x0a" + "\xae\x3c\x3f\x3f\xf4\xfb\x65\x52" + "\xc5\xc1\x78\x78\x53\x28\xad\xed" + "\xd1\x67\x37\xc7\x59\x70\xcd\x0a" + "\xb8\x0f\x80\x51\x9f\xc0\x12\x5e" + "\x06\x0a\x7e\xec\x24\x5f\x73\x00" + "\xb1\x0b\x31\x47\x4f\x73\x8d\xb4" + "\xce\xf3\x55\x45\x6c\x84\x27\xba" + "\xb9\x6f\x03\x4a\xeb\x98\x88\x6e" + "\x53\xed\x25\x19\x0d\x8f\xfe\xca" + "\x60\xe5\x00\x93\x6e\x3c\xff\x19" + "\xae\x08\x3b\x8a\xa6\x84\x05\xfe" + "\x9b\x59\xa0\x8c\xc8\x05\x45\xf5" + "\x05\x37\xdc\x45\x6f\x8b\x95\x8c" + "\x4e\x11\x45\x7a\xce\x21\xa5\xf7" + "\x71\x67\xb9\xce\xd7\xf9\xe9\x5e" + "\x60\xf5\x53\x7a\xa8\x85\x14\x03" + "\xa0\x92\xec\xf3\x51\x80\x84\xc4" + "\xdc\x11\x9e\x57\xce\x4b\x45\xcf" + "\x90\x95\x85\x0b\x96\xe9\xee\x35" + "\x10\xb8\x9b\xf2\x59\x4a\xc6\x7e" + "\x85\xe5\x6f\x38\x51\x93\x40\x0c" + "\x99\xd7\x7f\x32\xa8\x06\x27\xd1" + "\x2b\xd5\xb5\x3a\x1a\xe1\x5e\xda" + "\xcd\x5a\x50\x30\x3c\xc7\xe7\x65" + "\xa6\x07\x0b\x98\x91\xc6\x20\x27" + "\x2a\x03\x63\x1b\x1e\x3d\xaf\xc8" + "\x71\x48\x46\x6a\x64\x28\xf9\x3d" + "\xd1\x1d\xab\xc8\x40\x76\xc2\x39" + "\x4e\x00\x75\xd2\x0e\x82\x58\x8c" + "\xd3\x73\x5a\xea\x46\x89\xbe\xfd" + "\x4e\x2c\x0d\x94\xaa\x9b\x68\xac" + "\x86\x87\x30\x7e\xa9\x16\xcd\x59" + "\xd2\xa6\xbe\x0a\xd8\xf5\xfd\x2d" + "\x49\x69\xd2\x1a\x90\xd2\x1b\xed" + "\xff\x71\x04\x87\x87\x21\xc4\xb8" + "\x1f\x5b\x51\x33\xd0\xd6\x59\x9a" + "\x03\x0e\xd3\x8b\xfb\x57\x73\xfd" + "\x5a\x52\x63\x82\xc8\x85\x2f\xcb" + "\x74\x6d\x4e\xd9\x68\x37\x85\x6a" + "\xd4\xfb\x94\xed\x8d\xd1\x1a\xaf" + "\x76\xa7\xb7\x88\xd0\x2b\x4e\xda" + "\xec\x99\x94\x27\x6f\x87\x8c\xdf" + "\x4b\x5e\xa6\x66\xdd\xcb\x33\x7b" + "\x64\x94\x31\xa8\x37\xa6\x1d\xdb" + "\x0d\x5c\x93\xa4\x40\xf9\x30\x53" + "\x4b\x74\x8d\xdd\xf6\xde\x3c\xac" + "\x5c\x80\x01\x3a\xef\xb1\x9a\x02" + "\x0c\x22\x8e\xe7\x44\x09\x74\x4c" + "\xf2\x9a\x27\x69\x7f\x12\x32\x36" + "\xde\x92\xdf\xde\x8f\x5b\x31\xab" + "\x4a\x01\x26\xe0\xb1\xda\xe8\x37" + "\x21\x64\xe8\xff\x69\xfc\x9e\x41" + "\xd2\x96\x2d\x18\x64\x98\x33\x78" + "\x24\x61\x73\x9b\x47\x29\xf1\xa7" + "\xcb\x27\x0f\xf0\x85\x6d\x8c\x9d" + "\x2c\x95\x9e\xe5\xb2\x8e\x30\x29" + "\x78\x8a\x9d\x65\xb4\x8e\xde\x7b" + "\xd9\x00\x50\xf5\x7f\x81\xc3\x1b" + "\x25\x85\xeb\xc2\x8c\x33\x22\x1e" + "\x68\x38\x22\x30\xd8\x2e\x00\x98" + "\x85\x16\x06\x56\xb4\x81\x74\x20" + "\x95\xdb\x1c\x05\x19\xe8\x23\x4d" + "\x65\x5d\xcc\xd8\x7f\xc4\x2d\x0f" + "\x57\x26\x71\x07\xad\xaa\x71\x9f" + "\x19\x76\x2f\x25\x51\x88\xe4\xc0" + "\x82\x6e\x08\x05\x37\x04\xee\x25" + "\x23\x90\xe9\x4e\xce\x9b\x16\xc1" + "\x31\xe7\x6e\x2c\x1b\xe1\x85\x9a" + "\x0c\x8c\xbb\x12\x1e\x68\x7b\x93" + "\xa9\x3c\x39\x56\x23\x3e\x6e\xc7" + "\x77\x84\xd3\xe0\x86\x59\xaa\xb9" + "\xd5\x53\x58\xc9\x0a\x83\x5f\x85" + "\xd8\x47\x14\x67\x8a\x3c\x17\xe0" + "\xab\x02\x51\xea\xf1\xf0\x4f\x30" + "\x7d\xe0\x92\xc2\x5f\xfb\x19\x5a" + "\x3f\xbd\xf4\x39\xa4\x31\x0c\x39" + "\xd1\xae\x4e\xf7\x65\x7f\x1f\xce" + "\xc2\x39\xd1\x84\xd4\xe5\x02\xe0" + "\x58\xaa\xf1\x5e\x81\xaf\x7f\x72" + "\x0f\x08\x99\x43\xb9\xd8\xac\x41" + "\x35\x55\xf2\xb2\xd4\x98\xb8\x3b" + "\x2b\x3c\x3e\x16\x06\x31\xfc\x79" + "\x47\x38\x63\x51\xc5\xd0\x26\xd7" + "\x43\xb4\x2b\xd9\xc5\x05\xf2\x9d" + "\x18\xc9\x26\x82\x56\xd2\x11\x05" + "\xb6\x89\xb4\x43\x9c\xb5\x9d\x11" + "\x6c\x83\x37\x71\x27\x1c\xae\xbf" + "\xcd\x57\xd2\xee\x0d\x5a\x15\x26" + "\x67\x88\x80\x80\x1b\xdc\xc1\x62" + "\xdd\x4c\xff\x92\x5c\x6c\xe1\xa0" + "\xe3\x79\xa9\x65\x8c\x8c\x14\x42" + "\xe5\x11\xd2\x1a\xad\xa9\x56\x6f" + "\x98\xfc\x8a\x7b\x56\x1f\xc6\xc1" + "\x52\x12\x92\x9b\x41\x0f\x4b\xae" + "\x1b\x4a\xbc\xfe\x23\xb6\x94\x70" + "\x04\x30\x9e\x69\x47\xbe\xb8\x8f" + "\xca\x45\xd7\x8a\xf4\x78\x3e\xaa" + "\x71\x17\xd8\x1e\xb8\x11\x8f\xbc" + "\xc8\x1a\x65\x7b\x41\x89\x72\xc7" + "\x5f\xbe\xc5\x2a\xdb\x5c\x54\xf9" + "\x25\xa3\x7a\x80\x56\x9c\x8c\xab" + "\x26\x19\x10\x36\xa6\xf3\x14\x79" + "\x40\x98\x70\x68\xb7\x35\xd9\xb9" + "\x27\xd4\xe7\x74\x5b\x3d\x97\xb4" + "\xd9\xaa\xd9\xf2\xb5\x14\x84\x1f" + "\xa9\xde\x12\x44\x5b\x00\xc0\xbc" + "\xc8\x11\x25\x1b\x67\x7a\x15\x72" + "\xa6\x31\x6f\xf4\x68\x7a\x86\x9d" + "\x43\x1c\x5f\x16\xd3\xad\x2e\x52" + "\xf3\xb4\xc3\xfa\x27\x2e\x68\x6c" + "\x06\xe7\x4c\x4f\xa2\xe0\xe4\x21" + "\x5d\x9e\x33\x58\x8d\xbf\xd5\x70" + "\xf8\x80\xa5\xdd\xe7\x18\x79\xfa" + "\x7b\xfd\x09\x69\x2c\x37\x32\xa8" + "\x65\xfa\x8d\x8b\x5c\xcc\xe8\xf3" + "\x37\xf6\xa6\xc6\x5c\xa2\x66\x79" + "\xfa\x8a\xa7\xd1\x0b\x2e\x1b\x5e" + "\x95\x35\x00\x76\xae\x42\xf7\x50" + "\x51\x78\xfb\xb4\x28\x24\xde\x1a" + "\x70\x8b\xed\xca\x3c\x5e\xe4\xbd" + "\x28\xb5\xf3\x76\x4f\x67\x5d\x81" + "\xb2\x60\x87\xd9\x7b\x19\x1a\xa7" + "\x79\xa2\xfa\x3f\x9e\xa9\xd7\x25" + "\x61\xe1\x74\x31\xa2\x77\xa0\x1b" + "\xf6\xf7\xcb\xc5\xaa\x9e\xce\xf9" + "\x9b\x96\xef\x51\xc3\x1a\x44\x96" + "\xae\x17\x50\xab\x29\x08\xda\xcc" + "\x1a\xb3\x12\xd0\x24\xe4\xe2\xe0" + "\xc6\xe3\xcc\x82\xd0\xba\x47\x4c" + "\x3f\x49\xd7\xe8\xb6\x61\xaa\x65" + "\x25\x18\x40\x2d\x62\x25\x02\x71" + "\x61\xa2\xc1\xb2\x13\xd2\x71\x3f" + "\x43\x1a\xc9\x09\x92\xff\xd5\x57" + "\xf0\xfc\x5e\x1c\xf1\xf5\xf9\xf3" + "\x5b", + .len = 1281, + .also_non_np = 1, + .np = 3, + .tap = { 1200, 1, 80 }, + }, +}; + /* * CTS (Cipher Text Stealing) mode tests */ diff --git a/include/crypto/chacha.h b/include/crypto/chacha.h index ae79e9983c72f..3d261f5cd156d 100644 --- a/include/crypto/chacha.h +++ b/include/crypto/chacha.h @@ -5,6 +5,11 @@ * XChaCha extends ChaCha's nonce to 192 bits, while provably retaining ChaCha's * security. Here they share the same key size, tfm context, and setkey * function; only their IV size and encrypt/decrypt function differ. + * + * The ChaCha paper specifies 20, 12, and 8-round variants. In general, it is + * recommended to use the 20-round variant ChaCha20. However, the other + * variants can be needed in some performance-sensitive scenarios. The generic + * ChaCha code currently allows only the 20 and 12-round variants. */ #ifndef _CRYPTO_CHACHA_H @@ -39,6 +44,8 @@ void crypto_chacha_init(u32 *state, struct chacha_ctx *ctx, u8 *iv); int crypto_chacha20_setkey(struct crypto_skcipher *tfm, const u8 *key, unsigned int keysize); +int crypto_chacha12_setkey(struct crypto_skcipher *tfm, const u8 *key, + unsigned int keysize); int crypto_chacha_crypt(struct skcipher_request *req); int crypto_xchacha_crypt(struct skcipher_request *req); diff --git a/lib/chacha.c b/lib/chacha.c index 0a2c2e5b7b84d..c4d69a83fcd2d 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 */ - BUG_ON(nrounds != 20); + BUG_ON(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 -- 2.19.1.331.ge82ca0e54c-goog
