diff options
Diffstat (limited to 'crypto/shash.c')
| -rw-r--r-- | crypto/shash.c | 239 |
1 files changed, 239 insertions, 0 deletions
diff --git a/crypto/shash.c b/crypto/shash.c new file mode 100644 index 0000000..82ec4bd --- /dev/null +++ b/crypto/shash.c @@ -0,0 +1,239 @@ +/* + * Synchronous Cryptographic Hash operations. + * + * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the Free + * Software Foundation; either version 2 of the License, or (at your option) + * any later version. + * + */ + +#include <crypto/internal/hash.h> +#include <linux/err.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/seq_file.h> + +static inline struct crypto_shash *__crypto_shash_cast(struct crypto_tfm *tfm) +{ + return container_of(tfm, struct crypto_shash, base); +} + +static int shash_setkey_unaligned(struct crypto_shash *tfm, const u8 *key, + unsigned int keylen) +{ + struct shash_alg *shash = crypto_shash_alg(tfm); + unsigned long alignmask = crypto_shash_alignmask(tfm); + unsigned long absize; + u8 *buffer, *alignbuffer; + int err; + + absize = keylen + (alignmask & ~(CRYPTO_MINALIGN - 1)); + buffer = kmalloc(absize, GFP_KERNEL); + if (!buffer) + return -ENOMEM; + + alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); + memcpy(alignbuffer, key, keylen); + err = shash->setkey(tfm, alignbuffer, keylen); + memset(alignbuffer, 0, keylen); + kfree(buffer); + return err; +} + +int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key, + unsigned int keylen) +{ + struct shash_alg *shash = crypto_shash_alg(tfm); + unsigned long alignmask = crypto_shash_alignmask(tfm); + + if ((unsigned long)key & alignmask) + return shash_setkey_unaligned(tfm, key, keylen); + + return shash->setkey(tfm, key, keylen); +} +EXPORT_SYMBOL_GPL(crypto_shash_setkey); + +static inline unsigned int shash_align_buffer_size(unsigned len, + unsigned long mask) +{ + return len + (mask & ~(__alignof__(u8 __attribute__ ((aligned))) - 1)); +} + +static int shash_update_unaligned(struct shash_desc *desc, const u8 *data, + unsigned int len) +{ + struct crypto_shash *tfm = desc->tfm; + struct shash_alg *shash = crypto_shash_alg(tfm); + unsigned long alignmask = crypto_shash_alignmask(tfm); + unsigned int unaligned_len = alignmask + 1 - + ((unsigned long)data & alignmask); + u8 buf[shash_align_buffer_size(unaligned_len, alignmask)] + __attribute__ ((aligned)); + + memcpy(buf, data, unaligned_len); + + return shash->update(desc, buf, unaligned_len) ?: + shash->update(desc, data + unaligned_len, len - unaligned_len); +} + +int crypto_shash_update(struct shash_desc *desc, const u8 *data, + unsigned int len) +{ + struct crypto_shash *tfm = desc->tfm; + struct shash_alg *shash = crypto_shash_alg(tfm); + unsigned long alignmask = crypto_shash_alignmask(tfm); + + if ((unsigned long)data & alignmask) + return shash_update_unaligned(desc, data, len); + + return shash->update(desc, data, len); +} +EXPORT_SYMBOL_GPL(crypto_shash_update); + +static int shash_final_unaligned(struct shash_desc *desc, u8 *out) +{ + struct crypto_shash *tfm = desc->tfm; + unsigned long alignmask = crypto_shash_alignmask(tfm); + struct shash_alg *shash = crypto_shash_alg(tfm); + unsigned int ds = crypto_shash_digestsize(tfm); + u8 buf[shash_align_buffer_size(ds, alignmask)] + __attribute__ ((aligned)); + int err; + + err = shash->final(desc, buf); + memcpy(out, buf, ds); + return err; +} + +int crypto_shash_final(struct shash_desc *desc, u8 *out) +{ + struct crypto_shash *tfm = desc->tfm; + struct shash_alg *shash = crypto_shash_alg(tfm); + unsigned long alignmask = crypto_shash_alignmask(tfm); + + if ((unsigned long)out & alignmask) + return shash_final_unaligned(desc, out); + + return shash->final(desc, out); +} +EXPORT_SYMBOL_GPL(crypto_shash_final); + +static int shash_finup_unaligned(struct shash_desc *desc, const u8 *data, + unsigned int len, u8 *out) +{ + return crypto_shash_update(desc, data, len) ?: + crypto_shash_final(desc, out); +} + +int crypto_shash_finup(struct shash_desc *desc, const u8 *data, + unsigned int len, u8 *out) +{ + struct crypto_shash *tfm = desc->tfm; + struct shash_alg *shash = crypto_shash_alg(tfm); + unsigned long alignmask = crypto_shash_alignmask(tfm); + + if (((unsigned long)data | (unsigned long)out) & alignmask || + !shash->finup) + return shash_finup_unaligned(desc, data, len, out); + + return shash->finup(desc, data, len, out); +} +EXPORT_SYMBOL_GPL(crypto_shash_finup); + +static int shash_digest_unaligned(struct shash_desc *desc, const u8 *data, + unsigned int len, u8 *out) +{ + return crypto_shash_init(desc) ?: + crypto_shash_update(desc, data, len) ?: + crypto_shash_final(desc, out); +} + +int crypto_shash_digest(struct shash_desc *desc, const u8 *data, + unsigned int len, u8 *out) +{ + struct crypto_shash *tfm = desc->tfm; + struct shash_alg *shash = crypto_shash_alg(tfm); + unsigned long alignmask = crypto_shash_alignmask(tfm); + + if (((unsigned long)data | (unsigned long)out) & alignmask || + !shash->digest) + return shash_digest_unaligned(desc, data, len, out); + + return shash->digest(desc, data, len, out); +} +EXPORT_SYMBOL_GPL(crypto_shash_digest); + +static int crypto_shash_init_tfm(struct crypto_tfm *tfm, + const struct crypto_type *frontend) +{ + if (frontend->type != CRYPTO_ALG_TYPE_SHASH) + return -EINVAL; + return 0; +} + +static unsigned int crypto_shash_extsize(struct crypto_alg *alg, + const struct crypto_type *frontend) +{ + return alg->cra_ctxsize; +} + +static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg) + __attribute__ ((unused)); +static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg) +{ + struct shash_alg *salg = __crypto_shash_alg(alg); + + seq_printf(m, "type : shash\n"); + seq_printf(m, "blocksize : %u\n", alg->cra_blocksize); + seq_printf(m, "digestsize : %u\n", salg->digestsize); + seq_printf(m, "descsize : %u\n", salg->descsize); +} + +static const struct crypto_type crypto_shash_type = { + .extsize = crypto_shash_extsize, + .init_tfm = crypto_shash_init_tfm, +#ifdef CONFIG_PROC_FS + .show = crypto_shash_show, +#endif + .maskclear = ~CRYPTO_ALG_TYPE_MASK, + .maskset = CRYPTO_ALG_TYPE_MASK, + .type = CRYPTO_ALG_TYPE_SHASH, + .tfmsize = offsetof(struct crypto_shash, base), +}; + +struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type, + u32 mask) +{ + return __crypto_shash_cast( + crypto_alloc_tfm(alg_name, &crypto_shash_type, type, mask)); +} +EXPORT_SYMBOL_GPL(crypto_alloc_shash); + +int crypto_register_shash(struct shash_alg *alg) +{ + struct crypto_alg *base = &alg->base; + + if (alg->digestsize > PAGE_SIZE / 8 || + alg->descsize > PAGE_SIZE / 8) + return -EINVAL; + + base->cra_type = &crypto_shash_type; + base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK; + base->cra_flags |= CRYPTO_ALG_TYPE_SHASH; + + return crypto_register_alg(base); +} +EXPORT_SYMBOL_GPL(crypto_register_shash); + +int crypto_unregister_shash(struct shash_alg *alg) +{ + return crypto_unregister_alg(&alg->base); +} +EXPORT_SYMBOL_GPL(crypto_unregister_shash); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Synchronous cryptographic hash type"); |