xref: /freebsd/sys/crypto/chacha20/chacha-sw.c (revision 4d846d26)
1 /* This file is in the public domain. */
2 
3 #include <sys/cdefs.h>
4 __FBSDID("$FreeBSD$");
5 
6 #include <crypto/chacha20/chacha.h>
7 #include <opencrypto/xform_enc.h>
8 
9 static int
10 chacha20_xform_setkey(void *ctx, const uint8_t *key, int len)
11 {
12 
13 	if (len != CHACHA_MINKEYLEN && len != 32)
14 		return (EINVAL);
15 
16 	chacha_keysetup(ctx, key, len * 8);
17 	return (0);
18 }
19 
20 static void
21 chacha20_xform_reinit(void *ctx, const uint8_t *iv, size_t ivlen)
22 {
23 	KASSERT(ivlen == CHACHA_NONCELEN + CHACHA_CTRLEN,
24 	    ("%s: invalid IV length", __func__));
25 	chacha_ivsetup(ctx, iv + 8, iv);
26 }
27 
28 static void
29 chacha20_xform_crypt(void *ctx, const uint8_t *in, uint8_t *out)
30 {
31 
32 	chacha_encrypt_bytes(ctx, in, out, CHACHA_BLOCKLEN);
33 }
34 
35 static void
36 chacha20_xform_crypt_multi(void *ctx, const uint8_t *in, uint8_t *out,
37     size_t len)
38 {
39 	KASSERT(len % CHACHA_BLOCKLEN == 0, ("%s: invalid length", __func__));
40 	chacha_encrypt_bytes(ctx, in, out, len);
41 }
42 
43 static void
44 chacha20_xform_crypt_last(void *ctx, const uint8_t *in, uint8_t *out,
45     size_t len)
46 {
47 
48 	chacha_encrypt_bytes(ctx, in, out, len);
49 }
50 
51 const struct enc_xform enc_xform_chacha20 = {
52 	.type = CRYPTO_CHACHA20,
53 	.name = "chacha20",
54 	.ctxsize = sizeof(struct chacha_ctx),
55 	.blocksize = 1,
56 	.native_blocksize = CHACHA_BLOCKLEN,
57 	.ivsize = CHACHA_NONCELEN + CHACHA_CTRLEN,
58 	.minkey = CHACHA_MINKEYLEN,
59 	.maxkey = 32,
60 	.setkey = chacha20_xform_setkey,
61 	.reinit = chacha20_xform_reinit,
62 	.encrypt = chacha20_xform_crypt,
63 	.decrypt = chacha20_xform_crypt,
64 	.encrypt_multi = chacha20_xform_crypt_multi,
65 	.decrypt_multi = chacha20_xform_crypt_multi,
66 	.encrypt_last = chacha20_xform_crypt_last,
67 	.decrypt_last = chacha20_xform_crypt_last,
68 };
69