diff options
| author | Meng Yu <yumeng18@huawei.com> | 2021-03-27 12:56:16 +0300 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2021-04-02 10:28:14 +0300 |
| commit | 0ae869926fab00b95709518d72cca2d50a29eccd (patch) | |
| tree | f9fe4b9977053af3fffdd3239817248ad951a950 /drivers/crypto/hisilicon | |
| parent | 9bb3fbbff3710dfebeed2f8cf9ee61c415722543 (diff) | |
| download | linux-0ae869926fab00b95709518d72cca2d50a29eccd.tar.xz | |
crypto: hisilicon/hpre - Add processing of src_data in 'CURVE25519'
HPRE can only deal with src_data smaller than 'p' in 'CURVE25519'
algorithm, but 'rfc7748' says:
'Implementations MUST accept non-canonical values and process them as
if they had been reduced modulo the field prime'
So we get its modulus to p, and then deal it with HPRE.
Signed-off-by: Meng Yu <yumeng18@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'drivers/crypto/hisilicon')
| -rw-r--r-- | drivers/crypto/hisilicon/hpre/hpre_crypto.c | 22 |
1 files changed, 18 insertions, 4 deletions
diff --git a/drivers/crypto/hisilicon/hpre/hpre_crypto.c b/drivers/crypto/hisilicon/hpre/hpre_crypto.c index d743c540d602..f363653b32e9 100644 --- a/drivers/crypto/hisilicon/hpre/hpre_crypto.c +++ b/drivers/crypto/hisilicon/hpre/hpre_crypto.c @@ -1729,6 +1729,17 @@ static int hpre_curve25519_msg_request_set(struct hpre_ctx *ctx, return 0; } +static void hpre_curve25519_src_modulo_p(u8 *ptr) +{ + int i; + + for (i = 0; i < CURVE25519_KEY_SIZE - 1; i++) + ptr[i] = 0; + + /* The modulus is ptr's last byte minus '0xed'(last byte of p) */ + ptr[i] -= 0xed; +} + static int hpre_curve25519_src_init(struct hpre_asym_request *hpre_req, struct scatterlist *data, unsigned int len) { @@ -1767,10 +1778,13 @@ static int hpre_curve25519_src_init(struct hpre_asym_request *hpre_req, curve = ecc_get_curve25519(); fill_curve_param(p, curve->p, CURVE25519_KEY_SIZE, curve->g.ndigits); - if (memcmp(ptr, p, ctx->key_sz) >= 0) { - dev_err(dev, "gx is out of p!\n"); - goto err; - } + + /* + * When src_data equals (2^255 - 19) ~ (2^255 - 1), it is out of p, + * we get its modulus to p, and then use it. + */ + if (memcmp(ptr, p, ctx->key_sz) >= 0) + hpre_curve25519_src_modulo_p(ptr); hpre_req->src = ptr; msg->in = cpu_to_le64(dma); |