tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
crypto: null - Add default null skcipher
This patch adds a default null skcipher for users such as gcm
to perform copies on SG lists.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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+39
crypto/crypto_null.c
+39
crypto/crypto_null.c
···
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#include <linux/mm.h>
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#include <linux/string.h>
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static DEFINE_MUTEX(crypto_default_null_skcipher_lock);
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static struct crypto_blkcipher *crypto_default_null_skcipher;
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static int crypto_default_null_skcipher_refcnt;
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static int null_compress(struct crypto_tfm *tfm, const u8 *src,
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unsigned int slen, u8 *dst, unsigned int *dlen)
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{
···
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MODULE_ALIAS_CRYPTO("compress_null");
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MODULE_ALIAS_CRYPTO("digest_null");
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MODULE_ALIAS_CRYPTO("cipher_null");
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struct crypto_blkcipher *crypto_get_default_null_skcipher(void)
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{
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struct crypto_blkcipher *tfm;
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mutex_lock(&crypto_default_null_skcipher_lock);
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tfm = crypto_default_null_skcipher;
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if (!tfm) {
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tfm = crypto_alloc_blkcipher("ecb(cipher_null)", 0, 0);
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if (IS_ERR(tfm))
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goto unlock;
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crypto_default_null_skcipher = tfm;
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}
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crypto_default_null_skcipher_refcnt++;
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unlock:
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mutex_unlock(&crypto_default_null_skcipher_lock);
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return tfm;
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}
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EXPORT_SYMBOL_GPL(crypto_get_default_null_skcipher);
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void crypto_put_default_null_skcipher(void)
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{
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mutex_lock(&crypto_default_null_skcipher_lock);
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if (!--crypto_default_null_skcipher_refcnt) {
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crypto_free_blkcipher(crypto_default_null_skcipher);
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crypto_default_null_skcipher = NULL;
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}
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mutex_unlock(&crypto_default_null_skcipher_lock);
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}
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EXPORT_SYMBOL_GPL(crypto_put_default_null_skcipher);
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static int __init crypto_null_mod_init(void)
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{