oysteikt/heimdal
0
0
Fork 0
Code Issues 5 Pull Requests Releases Activity

krb5: Store a digest context in the crypto structure

Browse Source 
Creating and destroying an EVP_CTX_MD structure with every hash
operation is very expensive. Speed things up by caching one within
the krb5_crypto structure. krb5_crypto can already only be safely
used by one thread at a time - adding a message digest context here
shouldn't introduce any further threading risks.

Users of the stashed context must be careful to ensure that they
call no other hash functions whilst they are in the middle of using
the context.
This commit is contained in:
Simon Wilkinson
2018-05-14 14:21:28 +01:00
committed by Jeffrey Altman
parent fa1e998b53
commit e50faea7f0
12 changed files with 100 additions and 50 deletions
Download Patch File Download Diff File Expand all files Collapse all files

29
lib/krb5/crypto.c
View File

@@ -168,14 +168,17 @@ _key_schedule(krb5_context context,
static krb5_error_code
SHA1_checksum(krb5_context context,
krb5_crypto crypto,
struct _krb5_key_data *key,
unsigned usage,
const struct krb5_crypto_iov *iov,
int niov,
Checksum *C)
{
if (_krb5_evp_digest_iov(iov, niov, C->checksum.data,
NULL, EVP_sha1(), NULL) != 1)
if (_krb5_evp_digest_iov(crypto,
iov, niov,
C->checksum.data, NULL,
EVP_sha1(), NULL) != 1)
krb5_abortx(context, "sha1 checksum failed");
return 0;
@@ -184,6 +187,7 @@ SHA1_checksum(krb5_context context,
/* HMAC according to RFC2104 */
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
_krb5_internal_hmac_iov(krb5_context context,
krb5_crypto crypto,
struct _krb5_checksum_type *cm,
unsigned usage,
const struct krb5_crypto_iov *iov,
@@ -221,6 +225,7 @@ _krb5_internal_hmac_iov(krb5_context context,
working[0].data = keyblock->key->keyvalue;
working[0].flags = KRB5_CRYPTO_TYPE_DATA;
(*cm->checksum)(context,
crypto,
keyblock,
usage,
working,
@@ -243,14 +248,14 @@ _krb5_internal_hmac_iov(krb5_context context,
for (i = 0; i < niov; i++)
working[i + 1] = iov[i];
(*cm->checksum)(context, keyblock, usage, working, niov + 1, result);
(*cm->checksum)(context, crypto, keyblock, usage, working, niov + 1, result);
memcpy(opad + cm->blocksize, result->checksum.data,
result->checksum.length);
working[0].data.data = opad;
working[0].data.length = cm->blocksize + cm->checksumsize;
working[0].flags = KRB5_CRYPTO_TYPE_DATA;
(*cm->checksum)(context, keyblock, usage, working, 1, result);
(*cm->checksum)(context, crypto, keyblock, usage, working, 1, result);
memset(ipad, 0, cm->blocksize);
free(ipad);
memset(opad, 0, cm->blocksize + cm->checksumsize);
@@ -262,6 +267,7 @@ _krb5_internal_hmac_iov(krb5_context context,
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
_krb5_internal_hmac(krb5_context context,
krb5_crypto crypto,
struct _krb5_checksum_type *cm,
const void *data,
size_t len,
@@ -274,7 +280,7 @@ _krb5_internal_hmac(krb5_context context,
iov[0].data.data = (void *) data;
iov[0].data.length = len;
iov[0].flags = KRB5_CRYPTO_TYPE_DATA;
return _krb5_internal_hmac_iov(context, cm, usage, iov, 1,
return _krb5_internal_hmac_iov(context, crypto, cm, usage, iov, 1,
keyblock, result);
}
@@ -302,7 +308,7 @@ krb5_hmac(krb5_context context,
kd.key = key;
kd.schedule = NULL;
ret = _krb5_internal_hmac(context, c, data, len, usage, &kd, result);
ret = _krb5_internal_hmac(context, NULL, c, data, len, usage, &kd, result);
if (kd.schedule)
krb5_free_data(context, kd.schedule);
@@ -312,6 +318,7 @@ krb5_hmac(krb5_context context,
krb5_error_code
_krb5_SP_HMAC_SHA1_checksum(krb5_context context,
krb5_crypto crypto,
struct _krb5_key_data *key,
unsigned usage,
const struct krb5_crypto_iov *iov,
@@ -425,7 +432,7 @@ create_checksum_iov(krb5_context context,
result->cksumtype = ct->type;
return (*ct->checksum)(context, dkey, usage, iov, niov, result);
return (*ct->checksum)(context, crypto, dkey, usage, iov, niov, result);
}
static krb5_error_code
@@ -539,7 +546,7 @@ verify_checksum_iov(krb5_context context,
*/
if(ct->verify) {
ret = (*ct->verify)(context, dkey, usage, iov, niov, cksum);
ret = (*ct->verify)(context, crypto, dkey, usage, iov, niov, cksum);
if (ret)
krb5_set_error_message(context, ret,
N_("Decrypt integrity check failed for checksum "
@@ -552,7 +559,7 @@ verify_checksum_iov(krb5_context context,
if (ret)
return ret;
ret = (*ct->checksum)(context, dkey, usage, iov, niov, &c);
ret = (*ct->checksum)(context, crypto, dkey, usage, iov, niov, &c);
if (ret) {
krb5_data_free(&c.checksum);
return ret;
@@ -2515,6 +2522,10 @@ krb5_crypto_destroy(krb5_context context,
free_key_usage(context, &crypto->key_usage[i], crypto->et);
free(crypto->key_usage);
_krb5_free_key_data(context, &crypto->key, crypto->et);
if (crypto->mdctx)
EVP_MD_CTX_destroy(crypto->mdctx);
free (crypto);
return 0;
}