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