diff options
| -rw-r--r-- | arch/s390/crypto/phmac_s390.c | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/arch/s390/crypto/phmac_s390.c b/arch/s390/crypto/phmac_s390.c index 8473af47f5b9..90602f72108f 100644 --- a/arch/s390/crypto/phmac_s390.c +++ b/arch/s390/crypto/phmac_s390.c @@ -177,6 +177,114 @@ struct phmac_req_ctx { }; /* + * Pkey 'token' struct used to derive a protected key value from a clear key. + */ +struct hmac_clrkey_token { + u8 type; + u8 res0[3]; + u8 version; + u8 res1[3]; + u32 keytype; + u32 len; + u8 key[]; +} __packed; + +static int hash_key(const u8 *in, unsigned int inlen, + u8 *digest, unsigned int digestsize) +{ + unsigned long func; + union { + struct sha256_paramblock { + u32 h[8]; + u64 mbl; + } sha256; + struct sha512_paramblock { + u64 h[8]; + u128 mbl; + } sha512; + } __packed param; + +#define PARAM_INIT(x, y, z) \ + param.sha##x.h[0] = SHA##y ## _H0; \ + param.sha##x.h[1] = SHA##y ## _H1; \ + param.sha##x.h[2] = SHA##y ## _H2; \ + param.sha##x.h[3] = SHA##y ## _H3; \ + param.sha##x.h[4] = SHA##y ## _H4; \ + param.sha##x.h[5] = SHA##y ## _H5; \ + param.sha##x.h[6] = SHA##y ## _H6; \ + param.sha##x.h[7] = SHA##y ## _H7; \ + param.sha##x.mbl = (z) + + switch (digestsize) { + case SHA224_DIGEST_SIZE: + func = CPACF_KLMD_SHA_256; + PARAM_INIT(256, 224, inlen * 8); + break; + case SHA256_DIGEST_SIZE: + func = CPACF_KLMD_SHA_256; + PARAM_INIT(256, 256, inlen * 8); + break; + case SHA384_DIGEST_SIZE: + func = CPACF_KLMD_SHA_512; + PARAM_INIT(512, 384, inlen * 8); + break; + case SHA512_DIGEST_SIZE: + func = CPACF_KLMD_SHA_512; + PARAM_INIT(512, 512, inlen * 8); + break; + default: + return -EINVAL; + } + +#undef PARAM_INIT + + cpacf_klmd(func, ¶m, in, inlen); + + memcpy(digest, ¶m, digestsize); + + return 0; +} + +/* + * make_clrkey_token() - wrap the clear key into a pkey clearkey token. + */ +static inline int make_clrkey_token(const u8 *clrkey, size_t clrkeylen, + unsigned int digestsize, u8 *dest) +{ + struct hmac_clrkey_token *token = (struct hmac_clrkey_token *)dest; + unsigned int blocksize; + int rc; + + token->type = 0x00; + token->version = 0x02; + switch (digestsize) { + case SHA224_DIGEST_SIZE: + case SHA256_DIGEST_SIZE: + token->keytype = PKEY_KEYTYPE_HMAC_512; + blocksize = 64; + break; + case SHA384_DIGEST_SIZE: + case SHA512_DIGEST_SIZE: + token->keytype = PKEY_KEYTYPE_HMAC_1024; + blocksize = 128; + break; + default: + return -EINVAL; + } + token->len = blocksize; + + if (clrkeylen > blocksize) { + rc = hash_key(clrkey, clrkeylen, token->key, digestsize); + if (rc) + return rc; + } else { + memcpy(token->key, clrkey, clrkeylen); + } + + return 0; +} + +/* * phmac_tfm_ctx_setkey() - Set key value into tfm context, maybe construct * a clear key token digestible by pkey from a clear key value. */ @@ -623,8 +731,30 @@ static int phmac_setkey(struct crypto_ahash *tfm, { struct phmac_tfm_ctx *tfm_ctx = crypto_ahash_ctx(tfm); unsigned int ds = crypto_ahash_digestsize(tfm); + unsigned int bs = crypto_ahash_blocksize(tfm); + unsigned int tmpkeylen; + u8 *tmpkey = NULL; int rc = 0; + if (!crypto_ahash_tested(tfm)) { + /* + * selftest running: key is a raw hmac clear key and needs + * to get embedded into a 'clear key token' in order to have + * it correctly processed by the pkey module. + */ + tmpkeylen = sizeof(struct hmac_clrkey_token) + bs; + tmpkey = kzalloc(tmpkeylen, GFP_KERNEL); + if (!tmpkey) { + rc = -ENOMEM; + goto out; + } + rc = make_clrkey_token(key, keylen, ds, tmpkey); + if (rc) + goto out; + keylen = tmpkeylen; + key = tmpkey; + } + /* copy raw key into tfm context */ rc = phmac_tfm_ctx_setkey(tfm_ctx, key, keylen); if (rc) @@ -667,6 +797,7 @@ static int phmac_setkey(struct crypto_ahash *tfm, } out: + kfree(tmpkey); pr_debug("rc=%d\n", rc); return rc; } @@ -861,6 +992,12 @@ static int __init s390_phmac_init(void) struct phmac_alg *phmac; int i, rc; + /* for selftest cpacf klmd subfunction is needed */ + if (!cpacf_query_func(CPACF_KLMD, CPACF_KLMD_SHA_256)) + return -ENODEV; + if (!cpacf_query_func(CPACF_KLMD, CPACF_KLMD_SHA_512)) + return -ENODEV; + /* register a simple phmac pseudo misc device */ rc = misc_register(&phmac_dev); if (rc) |