@@ -1437,10 +1437,10 @@ config CRYPTO_SALSA20
Bernstein <djb@cr.yp.to>. 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.
@@ -1453,6 +1453,12 @@ 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 very performance-sensitive scenarios. There is no known
+ attack on XChaCha12 (or ChaCha12) yet, but it has a higher risk of
+ being broken than the 20-round variant.
+
config CRYPTO_CHACHA20_X86_64
tristate "ChaCha20 cipher algorithm (x86_64/SSSE3/AVX2)"
depends on X86 && 64BIT
@@ -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
@@ -105,6 +105,13 @@ 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);
@@ -167,6 +174,21 @@ 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,
}
};
@@ -190,3 +212,5 @@ 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");
@@ -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,
@@ -31990,6 +31990,584 @@ 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"
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+ "\x72",
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+ "\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
*/
@@ -5,6 +5,13 @@
* 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
+ * strongly recommended to use the 20-round variant ChaCha20. However, the
+ * reduced-round variants can be needed in some very performance-sensitive
+ * scenarios where a reduced security margin may be tolerated.
+ *
+ * The generic ChaCha code currently allows only the 20 and 12-round variants.
*/
#ifndef _CRYPTO_CHACHA_H
@@ -40,6 +47,8 @@ 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);
@@ -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