diff options
Diffstat (limited to 'crypto/crypto_null.c')
| -rw-r--r-- | crypto/crypto_null.c | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/crypto/crypto_null.c b/crypto/crypto_null.c index a20319132e33..941c9a434d50 100644 --- a/crypto/crypto_null.c +++ b/crypto/crypto_null.c @@ -25,6 +25,10 @@ #include <linux/mm.h> #include <linux/string.h> +static DEFINE_MUTEX(crypto_default_null_skcipher_lock); +static struct crypto_blkcipher *crypto_default_null_skcipher; +static int crypto_default_null_skcipher_refcnt; + static int null_compress(struct crypto_tfm *tfm, const u8 *src, unsigned int slen, u8 *dst, unsigned int *dlen) { @@ -149,6 +153,41 @@ MODULE_ALIAS_CRYPTO("compress_null"); MODULE_ALIAS_CRYPTO("digest_null"); MODULE_ALIAS_CRYPTO("cipher_null"); +struct crypto_blkcipher *crypto_get_default_null_skcipher(void) +{ + struct crypto_blkcipher *tfm; + + mutex_lock(&crypto_default_null_skcipher_lock); + tfm = crypto_default_null_skcipher; + + if (!tfm) { + tfm = crypto_alloc_blkcipher("ecb(cipher_null)", 0, 0); + if (IS_ERR(tfm)) + goto unlock; + + crypto_default_null_skcipher = tfm; + } + + crypto_default_null_skcipher_refcnt++; + +unlock: + mutex_unlock(&crypto_default_null_skcipher_lock); + + return tfm; +} +EXPORT_SYMBOL_GPL(crypto_get_default_null_skcipher); + +void crypto_put_default_null_skcipher(void) +{ + mutex_lock(&crypto_default_null_skcipher_lock); + if (!--crypto_default_null_skcipher_refcnt) { + crypto_free_blkcipher(crypto_default_null_skcipher); + crypto_default_null_skcipher = NULL; + } + mutex_unlock(&crypto_default_null_skcipher_lock); +} +EXPORT_SYMBOL_GPL(crypto_put_default_null_skcipher); + static int __init crypto_null_mod_init(void) { int ret = 0; |