From 7613636def82092a5c7b6322078a2af832410417 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Tue, 20 Nov 2007 17:26:06 +0800 Subject: [CRYPTO] api: Add crypto_inc and crypto_xor With the addition of more stream ciphers we need to curb the proliferation of ad-hoc xor functions. This patch creates a generic pair of functions, crypto_inc and crypto_xor which does big-endian increment and exclusive or, respectively. For optimum performance, they both use u32 operations so alignment must be as that of u32 even though the arguments are of type u8 *. Signed-off-by: Herbert Xu --- crypto/algapi.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) (limited to 'crypto/algapi.c') diff --git a/crypto/algapi.c b/crypto/algapi.c index 8383282de1dd..08eca6da1d53 100644 --- a/crypto/algapi.c +++ b/crypto/algapi.c @@ -605,6 +605,53 @@ int crypto_tfm_in_queue(struct crypto_queue *queue, struct crypto_tfm *tfm) } EXPORT_SYMBOL_GPL(crypto_tfm_in_queue); +static inline void crypto_inc_byte(u8 *a, unsigned int size) +{ + u8 *b = (a + size); + u8 c; + + for (; size; size--) { + c = *--b + 1; + *b = c; + if (c) + break; + } +} + +void crypto_inc(u8 *a, unsigned int size) +{ + __be32 *b = (__be32 *)(a + size); + u32 c; + + for (; size >= 4; size -= 4) { + c = be32_to_cpu(*--b) + 1; + *b = cpu_to_be32(c); + if (c) + return; + } + + crypto_inc_byte(a, size); +} +EXPORT_SYMBOL_GPL(crypto_inc); + +static inline void crypto_xor_byte(u8 *a, const u8 *b, unsigned int size) +{ + for (; size; size--) + *a++ ^= *b++; +} + +void crypto_xor(u8 *dst, const u8 *src, unsigned int size) +{ + u32 *a = (u32 *)dst; + u32 *b = (u32 *)src; + + for (; size >= 4; size -= 4) + *a++ ^= *b++; + + crypto_xor_byte((u8 *)a, (u8 *)b, size); +} +EXPORT_SYMBOL_GPL(crypto_xor); + static int __init crypto_algapi_init(void) { crypto_init_proc(); -- cgit v1.2.3 From 68b6c7d6919be7c732fc6229c55e35d0166e9258 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Fri, 7 Dec 2007 20:18:17 +0800 Subject: [CRYPTO] api: Add crypto_attr_alg_name This patch adds a new helper crypto_attr_alg_name which is basically the first half of crypto_attr_alg. That is, it returns an algorithm name parameter as a string without looking it up. The caller can then look it up immediately or defer it until later. Signed-off-by: Herbert Xu --- crypto/algapi.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) (limited to 'crypto/algapi.c') diff --git a/crypto/algapi.c b/crypto/algapi.c index 08eca6da1d53..e65cb50cf4af 100644 --- a/crypto/algapi.c +++ b/crypto/algapi.c @@ -472,7 +472,7 @@ int crypto_check_attr_type(struct rtattr **tb, u32 type) } EXPORT_SYMBOL_GPL(crypto_check_attr_type); -struct crypto_alg *crypto_attr_alg(struct rtattr *rta, u32 type, u32 mask) +const char *crypto_attr_alg_name(struct rtattr *rta) { struct crypto_attr_alg *alga; @@ -486,7 +486,21 @@ struct crypto_alg *crypto_attr_alg(struct rtattr *rta, u32 type, u32 mask) alga = RTA_DATA(rta); alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0; - return crypto_alg_mod_lookup(alga->name, type, mask); + return alga->name; +} +EXPORT_SYMBOL_GPL(crypto_attr_alg_name); + +struct crypto_alg *crypto_attr_alg(struct rtattr *rta, u32 type, u32 mask) +{ + const char *name; + int err; + + name = crypto_attr_alg_name(rta); + err = PTR_ERR(name); + if (IS_ERR(name)) + return ERR_PTR(err); + + return crypto_alg_mod_lookup(name, type, mask); } EXPORT_SYMBOL_GPL(crypto_attr_alg); -- cgit v1.2.3