diff options
Diffstat (limited to 'crypto/cipher.c')
-rw-r--r-- | crypto/cipher.c | 447 |
1 files changed, 3 insertions, 444 deletions
diff --git a/crypto/cipher.c b/crypto/cipher.c index 9e03701cfdc..333aab2f027 100644 --- a/crypto/cipher.c +++ b/crypto/cipher.c @@ -12,274 +12,13 @@ * any later version. * */ -#include <linux/compiler.h> + #include <linux/kernel.h> #include <linux/crypto.h> #include <linux/errno.h> -#include <linux/mm.h> -#include <linux/slab.h> +#include <linux/scatterlist.h> #include <linux/string.h> -#include <asm/scatterlist.h> #include "internal.h" -#include "scatterwalk.h" - -struct cipher_alg_compat { - unsigned int cia_min_keysize; - unsigned int cia_max_keysize; - int (*cia_setkey)(struct crypto_tfm *tfm, const u8 *key, - unsigned int keylen); - void (*cia_encrypt)(struct crypto_tfm *tfm, u8 *dst, const u8 *src); - void (*cia_decrypt)(struct crypto_tfm *tfm, u8 *dst, const u8 *src); - - unsigned int (*cia_encrypt_ecb)(const struct cipher_desc *desc, - u8 *dst, const u8 *src, - unsigned int nbytes); - unsigned int (*cia_decrypt_ecb)(const struct cipher_desc *desc, - u8 *dst, const u8 *src, - unsigned int nbytes); - unsigned int (*cia_encrypt_cbc)(const struct cipher_desc *desc, - u8 *dst, const u8 *src, - unsigned int nbytes); - unsigned int (*cia_decrypt_cbc)(const struct cipher_desc *desc, - u8 *dst, const u8 *src, - unsigned int nbytes); -}; - -static inline void xor_64(u8 *a, const u8 *b) -{ - ((u32 *)a)[0] ^= ((u32 *)b)[0]; - ((u32 *)a)[1] ^= ((u32 *)b)[1]; -} - -static inline void xor_128(u8 *a, const u8 *b) -{ - ((u32 *)a)[0] ^= ((u32 *)b)[0]; - ((u32 *)a)[1] ^= ((u32 *)b)[1]; - ((u32 *)a)[2] ^= ((u32 *)b)[2]; - ((u32 *)a)[3] ^= ((u32 *)b)[3]; -} - -static unsigned int crypt_slow(const struct cipher_desc *desc, - struct scatter_walk *in, - struct scatter_walk *out, unsigned int bsize) -{ - unsigned long alignmask = crypto_tfm_alg_alignmask(desc->tfm); - u8 buffer[bsize * 2 + alignmask]; - u8 *src = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); - u8 *dst = src + bsize; - - scatterwalk_copychunks(src, in, bsize, 0); - desc->prfn(desc, dst, src, bsize); - scatterwalk_copychunks(dst, out, bsize, 1); - - return bsize; -} - -static inline unsigned int crypt_fast(const struct cipher_desc *desc, - struct scatter_walk *in, - struct scatter_walk *out, - unsigned int nbytes, u8 *tmp) -{ - u8 *src, *dst; - u8 *real_src, *real_dst; - - real_src = scatterwalk_map(in, 0); - real_dst = scatterwalk_map(out, 1); - - src = real_src; - dst = scatterwalk_samebuf(in, out) ? src : real_dst; - - if (tmp) { - memcpy(tmp, src, nbytes); - src = tmp; - dst = tmp; - } - - nbytes = desc->prfn(desc, dst, src, nbytes); - - if (tmp) - memcpy(real_dst, tmp, nbytes); - - scatterwalk_unmap(real_src, 0); - scatterwalk_unmap(real_dst, 1); - - scatterwalk_advance(in, nbytes); - scatterwalk_advance(out, nbytes); - - return nbytes; -} - -/* - * Generic encrypt/decrypt wrapper for ciphers, handles operations across - * multiple page boundaries by using temporary blocks. In user context, - * the kernel is given a chance to schedule us once per page. - */ -static int crypt(const struct cipher_desc *desc, - struct scatterlist *dst, - struct scatterlist *src, - unsigned int nbytes) -{ - struct scatter_walk walk_in, walk_out; - struct crypto_tfm *tfm = desc->tfm; - const unsigned int bsize = crypto_tfm_alg_blocksize(tfm); - unsigned int alignmask = crypto_tfm_alg_alignmask(tfm); - unsigned long buffer = 0; - - if (!nbytes) - return 0; - - if (nbytes % bsize) { - tfm->crt_flags |= CRYPTO_TFM_RES_BAD_BLOCK_LEN; - return -EINVAL; - } - - scatterwalk_start(&walk_in, src); - scatterwalk_start(&walk_out, dst); - - for(;;) { - unsigned int n = nbytes; - u8 *tmp = NULL; - - if (!scatterwalk_aligned(&walk_in, alignmask) || - !scatterwalk_aligned(&walk_out, alignmask)) { - if (!buffer) { - buffer = __get_free_page(GFP_ATOMIC); - if (!buffer) - n = 0; - } - tmp = (u8 *)buffer; - } - - n = scatterwalk_clamp(&walk_in, n); - n = scatterwalk_clamp(&walk_out, n); - - if (likely(n >= bsize)) - n = crypt_fast(desc, &walk_in, &walk_out, n, tmp); - else - n = crypt_slow(desc, &walk_in, &walk_out, bsize); - - nbytes -= n; - - scatterwalk_done(&walk_in, 0, nbytes); - scatterwalk_done(&walk_out, 1, nbytes); - - if (!nbytes) - break; - - crypto_yield(tfm->crt_flags); - } - - if (buffer) - free_page(buffer); - - return 0; -} - -static int crypt_iv_unaligned(struct cipher_desc *desc, - struct scatterlist *dst, - struct scatterlist *src, - unsigned int nbytes) -{ - struct crypto_tfm *tfm = desc->tfm; - unsigned long alignmask = crypto_tfm_alg_alignmask(tfm); - u8 *iv = desc->info; - - if (unlikely(((unsigned long)iv & alignmask))) { - unsigned int ivsize = tfm->crt_cipher.cit_ivsize; - u8 buffer[ivsize + alignmask]; - u8 *tmp = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); - int err; - - desc->info = memcpy(tmp, iv, ivsize); - err = crypt(desc, dst, src, nbytes); - memcpy(iv, tmp, ivsize); - - return err; - } - - return crypt(desc, dst, src, nbytes); -} - -static unsigned int cbc_process_encrypt(const struct cipher_desc *desc, - u8 *dst, const u8 *src, - unsigned int nbytes) -{ - struct crypto_tfm *tfm = desc->tfm; - void (*xor)(u8 *, const u8 *) = tfm->crt_u.cipher.cit_xor_block; - int bsize = crypto_tfm_alg_blocksize(tfm); - - void (*fn)(struct crypto_tfm *, u8 *, const u8 *) = desc->crfn; - u8 *iv = desc->info; - unsigned int done = 0; - - nbytes -= bsize; - - do { - xor(iv, src); - fn(tfm, dst, iv); - memcpy(iv, dst, bsize); - - src += bsize; - dst += bsize; - } while ((done += bsize) <= nbytes); - - return done; -} - -static unsigned int cbc_process_decrypt(const struct cipher_desc *desc, - u8 *dst, const u8 *src, - unsigned int nbytes) -{ - struct crypto_tfm *tfm = desc->tfm; - void (*xor)(u8 *, const u8 *) = tfm->crt_u.cipher.cit_xor_block; - int bsize = crypto_tfm_alg_blocksize(tfm); - unsigned long alignmask = crypto_tfm_alg_alignmask(desc->tfm); - - u8 stack[src == dst ? bsize + alignmask : 0]; - u8 *buf = (u8 *)ALIGN((unsigned long)stack, alignmask + 1); - u8 **dst_p = src == dst ? &buf : &dst; - - void (*fn)(struct crypto_tfm *, u8 *, const u8 *) = desc->crfn; - u8 *iv = desc->info; - unsigned int done = 0; - - nbytes -= bsize; - - do { - u8 *tmp_dst = *dst_p; - - fn(tfm, tmp_dst, src); - xor(tmp_dst, iv); - memcpy(iv, src, bsize); - if (tmp_dst != dst) - memcpy(dst, tmp_dst, bsize); - - src += bsize; - dst += bsize; - } while ((done += bsize) <= nbytes); - - return done; -} - -static unsigned int ecb_process(const struct cipher_desc *desc, u8 *dst, - const u8 *src, unsigned int nbytes) -{ - struct crypto_tfm *tfm = desc->tfm; - int bsize = crypto_tfm_alg_blocksize(tfm); - void (*fn)(struct crypto_tfm *, u8 *, const u8 *) = desc->crfn; - unsigned int done = 0; - - nbytes -= bsize; - - do { - fn(tfm, dst, src); - - src += bsize; - dst += bsize; - } while ((done += bsize) <= nbytes); - - return done; -} static int setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen) { @@ -293,122 +32,6 @@ static int setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen) return cia->cia_setkey(tfm, key, keylen); } -static int ecb_encrypt(struct crypto_tfm *tfm, - struct scatterlist *dst, - struct scatterlist *src, unsigned int nbytes) -{ - struct cipher_desc desc; - struct cipher_alg_compat *cipher = (void *)&tfm->__crt_alg->cra_cipher; - - desc.tfm = tfm; - desc.crfn = cipher->cia_encrypt; - desc.prfn = cipher->cia_encrypt_ecb ?: ecb_process; - - return crypt(&desc, dst, src, nbytes); -} - -static int ecb_decrypt(struct crypto_tfm *tfm, - struct scatterlist *dst, - struct scatterlist *src, - unsigned int nbytes) -{ - struct cipher_desc desc; - struct cipher_alg_compat *cipher = (void *)&tfm->__crt_alg->cra_cipher; - - desc.tfm = tfm; - desc.crfn = cipher->cia_decrypt; - desc.prfn = cipher->cia_decrypt_ecb ?: ecb_process; - - return crypt(&desc, dst, src, nbytes); -} - -static int cbc_encrypt(struct crypto_tfm *tfm, - struct scatterlist *dst, - struct scatterlist *src, - unsigned int nbytes) -{ - struct cipher_desc desc; - struct cipher_alg_compat *cipher = (void *)&tfm->__crt_alg->cra_cipher; - - desc.tfm = tfm; - desc.crfn = cipher->cia_encrypt; - desc.prfn = cipher->cia_encrypt_cbc ?: cbc_process_encrypt; - desc.info = tfm->crt_cipher.cit_iv; - - return crypt(&desc, dst, src, nbytes); -} - -static int cbc_encrypt_iv(struct crypto_tfm *tfm, - struct scatterlist *dst, - struct scatterlist *src, - unsigned int nbytes, u8 *iv) -{ - struct cipher_desc desc; - struct cipher_alg_compat *cipher = (void *)&tfm->__crt_alg->cra_cipher; - - desc.tfm = tfm; - desc.crfn = cipher->cia_encrypt; - desc.prfn = cipher->cia_encrypt_cbc ?: cbc_process_encrypt; - desc.info = iv; - - return crypt_iv_unaligned(&desc, dst, src, nbytes); -} - -static int cbc_decrypt(struct crypto_tfm *tfm, - struct scatterlist *dst, - struct scatterlist *src, - unsigned int nbytes) -{ - struct cipher_desc desc; - struct cipher_alg_compat *cipher = (void *)&tfm->__crt_alg->cra_cipher; - - desc.tfm = tfm; - desc.crfn = cipher->cia_decrypt; - desc.prfn = cipher->cia_decrypt_cbc ?: cbc_process_decrypt; - desc.info = tfm->crt_cipher.cit_iv; - - return crypt(&desc, dst, src, nbytes); -} - -static int cbc_decrypt_iv(struct crypto_tfm *tfm, - struct scatterlist *dst, - struct scatterlist *src, - unsigned int nbytes, u8 *iv) -{ - struct cipher_desc desc; - struct cipher_alg_compat *cipher = (void *)&tfm->__crt_alg->cra_cipher; - - desc.tfm = tfm; - desc.crfn = cipher->cia_decrypt; - desc.prfn = cipher->cia_decrypt_cbc ?: cbc_process_decrypt; - desc.info = iv; - - return crypt_iv_unaligned(&desc, dst, src, nbytes); -} - -static int nocrypt(struct crypto_tfm *tfm, - struct scatterlist *dst, - struct scatterlist *src, - unsigned int nbytes) -{ - return -ENOSYS; -} - -static int nocrypt_iv(struct crypto_tfm *tfm, - struct scatterlist *dst, - struct scatterlist *src, - unsigned int nbytes, u8 *iv) -{ - return -ENOSYS; -} - -int crypto_init_cipher_flags(struct crypto_tfm *tfm, u32 flags) -{ - u32 mode = flags & CRYPTO_TFM_MODE_MASK; - tfm->crt_cipher.cit_mode = mode ? mode : CRYPTO_TFM_MODE_ECB; - return 0; -} - static void cipher_crypt_unaligned(void (*fn)(struct crypto_tfm *, u8 *, const u8 *), struct crypto_tfm *tfm, @@ -454,7 +77,6 @@ static void cipher_decrypt_unaligned(struct crypto_tfm *tfm, int crypto_init_cipher_ops(struct crypto_tfm *tfm) { - int ret = 0; struct cipher_tfm *ops = &tfm->crt_cipher; struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher; @@ -464,70 +86,7 @@ int crypto_init_cipher_ops(struct crypto_tfm *tfm) ops->cit_decrypt_one = crypto_tfm_alg_alignmask(tfm) ? cipher_decrypt_unaligned : cipher->cia_decrypt; - switch (tfm->crt_cipher.cit_mode) { - case CRYPTO_TFM_MODE_ECB: - ops->cit_encrypt = ecb_encrypt; - ops->cit_decrypt = ecb_decrypt; - ops->cit_encrypt_iv = nocrypt_iv; - ops->cit_decrypt_iv = nocrypt_iv; - break; - - case CRYPTO_TFM_MODE_CBC: - ops->cit_encrypt = cbc_encrypt; - ops->cit_decrypt = cbc_decrypt; - ops->cit_encrypt_iv = cbc_encrypt_iv; - ops->cit_decrypt_iv = cbc_decrypt_iv; - break; - - case CRYPTO_TFM_MODE_CFB: - ops->cit_encrypt = nocrypt; - ops->cit_decrypt = nocrypt; - ops->cit_encrypt_iv = nocrypt_iv; - ops->cit_decrypt_iv = nocrypt_iv; - break; - - case CRYPTO_TFM_MODE_CTR: - ops->cit_encrypt = nocrypt; - ops->cit_decrypt = nocrypt; - ops->cit_encrypt_iv = nocrypt_iv; - ops->cit_decrypt_iv = nocrypt_iv; - break; - - default: - BUG(); - } - - if (ops->cit_mode == CRYPTO_TFM_MODE_CBC) { - unsigned long align; - unsigned long addr; - - switch (crypto_tfm_alg_blocksize(tfm)) { - case 8: - ops->cit_xor_block = xor_64; - break; - - case 16: - ops->cit_xor_block = xor_128; - break; - - default: - printk(KERN_WARNING "%s: block size %u not supported\n", - crypto_tfm_alg_name(tfm), - crypto_tfm_alg_blocksize(tfm)); - ret = -EINVAL; - goto out; - } - - ops->cit_ivsize = crypto_tfm_alg_blocksize(tfm); - align = crypto_tfm_alg_alignmask(tfm) + 1; - addr = (unsigned long)crypto_tfm_ctx(tfm); - addr = ALIGN(addr, align); - addr += ALIGN(tfm->__crt_alg->cra_ctxsize, align); - ops->cit_iv = (void *)addr; - } - -out: - return ret; + return 0; } void crypto_exit_cipher_ops(struct crypto_tfm *tfm) |