--- /dev/null
+/*
+ * Block chaining cipher operations.
+ *
+ * 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.
+ *
+ * Copyright (c) 2006 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 <linux/crypto.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/scatterlist.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+
+#include "internal.h"
+#include "scatterwalk.h"
+
+enum {
+ BLKCIPHER_WALK_PHYS = 1 << 0,
+ BLKCIPHER_WALK_SLOW = 1 << 1,
+ BLKCIPHER_WALK_COPY = 1 << 2,
+ BLKCIPHER_WALK_DIFF = 1 << 3,
+};
+
+static int blkcipher_walk_next(struct blkcipher_desc *desc,
+ struct blkcipher_walk *walk);
+static int blkcipher_walk_first(struct blkcipher_desc *desc,
+ struct blkcipher_walk *walk);
+
+static inline void blkcipher_map_src(struct blkcipher_walk *walk)
+{
+ walk->src.virt.addr = scatterwalk_map(&walk->in, 0);
+}
+
+static inline void blkcipher_map_dst(struct blkcipher_walk *walk)
+{
+ walk->dst.virt.addr = scatterwalk_map(&walk->out, 1);
+}
+
+static inline void blkcipher_unmap_src(struct blkcipher_walk *walk)
+{
+ scatterwalk_unmap(walk->src.virt.addr, 0);
+}
+
+static inline void blkcipher_unmap_dst(struct blkcipher_walk *walk)
+{
+ scatterwalk_unmap(walk->dst.virt.addr, 1);
+}
+
+static inline u8 *blkcipher_get_spot(u8 *start, unsigned int len)
+{
+ if (offset_in_page(start + len) < len)
+ return (u8 *)((unsigned long)(start + len) & PAGE_MASK);
+ return start;
+}
+
+static inline unsigned int blkcipher_done_slow(struct crypto_blkcipher *tfm,
+ struct blkcipher_walk *walk,
+ unsigned int bsize)
+{
+ u8 *addr;
+ unsigned int alignmask = crypto_blkcipher_alignmask(tfm);
+
+ addr = (u8 *)ALIGN((unsigned long)walk->buffer, alignmask + 1);
+ addr = blkcipher_get_spot(addr, bsize);
+ scatterwalk_copychunks(addr, &walk->out, bsize, 1);
+ return bsize;
+}
+
+static inline unsigned int blkcipher_done_fast(struct blkcipher_walk *walk,
+ unsigned int n)
+{
+ n = walk->nbytes - n;
+
+ if (walk->flags & BLKCIPHER_WALK_COPY) {
+ blkcipher_map_dst(walk);
+ memcpy(walk->dst.virt.addr, walk->page, n);
+ blkcipher_unmap_dst(walk);
+ } else if (!(walk->flags & BLKCIPHER_WALK_PHYS)) {
+ blkcipher_unmap_src(walk);
+ if (walk->flags & BLKCIPHER_WALK_DIFF)
+ blkcipher_unmap_dst(walk);
+ }
+
+ scatterwalk_advance(&walk->in, n);
+ scatterwalk_advance(&walk->out, n);
+
+ return n;
+}
+
+int blkcipher_walk_done(struct blkcipher_desc *desc,
+ struct blkcipher_walk *walk, int err)
+{
+ struct crypto_blkcipher *tfm = desc->tfm;
+ unsigned int nbytes = 0;
+
+ if (likely(err >= 0)) {
+ unsigned int bsize = crypto_blkcipher_blocksize(tfm);
+ unsigned int n;
+
+ if (likely(!(walk->flags & BLKCIPHER_WALK_SLOW)))
+ n = blkcipher_done_fast(walk, err);
+ else
+ n = blkcipher_done_slow(tfm, walk, bsize);
+
+ nbytes = walk->total - n;
+ err = 0;
+ }
+
+ scatterwalk_done(&walk->in, 0, nbytes);
+ scatterwalk_done(&walk->out, 1, nbytes);
+
+ walk->total = nbytes;
+ walk->nbytes = nbytes;
+
+ if (nbytes) {
+ crypto_yield(desc->flags);
+ return blkcipher_walk_next(desc, walk);
+ }
+
+ if (walk->iv != desc->info)
+ memcpy(desc->info, walk->iv, crypto_blkcipher_ivsize(tfm));
+ if (walk->buffer != walk->page)
+ kfree(walk->buffer);
+ if (walk->page)
+ free_page((unsigned long)walk->page);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(blkcipher_walk_done);
+
+static inline int blkcipher_next_slow(struct blkcipher_desc *desc,
+ struct blkcipher_walk *walk,
+ unsigned int bsize,
+ unsigned int alignmask)
+{
+ unsigned int n;
+
+ if (walk->buffer)
+ goto ok;
+
+ walk->buffer = walk->page;
+ if (walk->buffer)
+ goto ok;
+
+ n = bsize * 2 + (alignmask & ~(crypto_tfm_ctx_alignment() - 1));
+ walk->buffer = kmalloc(n, GFP_ATOMIC);
+ if (!walk->buffer)
+ return blkcipher_walk_done(desc, walk, -ENOMEM);
+
+ok:
+ walk->dst.virt.addr = (u8 *)ALIGN((unsigned long)walk->buffer,
+ alignmask + 1);
+ walk->dst.virt.addr = blkcipher_get_spot(walk->dst.virt.addr, bsize);
+ walk->src.virt.addr = blkcipher_get_spot(walk->dst.virt.addr + bsize,
+ bsize);
+
+ scatterwalk_copychunks(walk->src.virt.addr, &walk->in, bsize, 0);
+
+ walk->nbytes = bsize;
+ walk->flags |= BLKCIPHER_WALK_SLOW;
+
+ return 0;
+}
+
+static inline int blkcipher_next_copy(struct blkcipher_walk *walk)
+{
+ u8 *tmp = walk->page;
+
+ blkcipher_map_src(walk);
+ memcpy(tmp, walk->src.virt.addr, walk->nbytes);
+ blkcipher_unmap_src(walk);
+
+ walk->src.virt.addr = tmp;
+ walk->dst.virt.addr = tmp;
+
+ return 0;
+}
+
+static inline int blkcipher_next_fast(struct blkcipher_desc *desc,
+ struct blkcipher_walk *walk)
+{
+ unsigned long diff;
+
+ walk->src.phys.page = scatterwalk_page(&walk->in);
+ walk->src.phys.offset = offset_in_page(walk->in.offset);
+ walk->dst.phys.page = scatterwalk_page(&walk->out);
+ walk->dst.phys.offset = offset_in_page(walk->out.offset);
+
+ if (walk->flags & BLKCIPHER_WALK_PHYS)
+ return 0;
+
+ diff = walk->src.phys.offset - walk->dst.phys.offset;
+ diff |= walk->src.virt.page - walk->dst.virt.page;
+
+ blkcipher_map_src(walk);
+ walk->dst.virt.addr = walk->src.virt.addr;
+
+ if (diff) {
+ walk->flags |= BLKCIPHER_WALK_DIFF;
+ blkcipher_map_dst(walk);
+ }
+
+ return 0;
+}
+
+static int blkcipher_walk_next(struct blkcipher_desc *desc,
+ struct blkcipher_walk *walk)
+{
+ struct crypto_blkcipher *tfm = desc->tfm;
+ unsigned int alignmask = crypto_blkcipher_alignmask(tfm);
+ unsigned int bsize = crypto_blkcipher_blocksize(tfm);
+ unsigned int n;
+ int err;
+
+ n = walk->total;
+ if (unlikely(n < bsize)) {
+ desc->flags |= CRYPTO_TFM_RES_BAD_BLOCK_LEN;
+ return blkcipher_walk_done(desc, walk, -EINVAL);
+ }
+
+ walk->flags &= ~(BLKCIPHER_WALK_SLOW | BLKCIPHER_WALK_COPY |
+ BLKCIPHER_WALK_DIFF);
+ if (!scatterwalk_aligned(&walk->in, alignmask) ||
+ !scatterwalk_aligned(&walk->out, alignmask)) {
+ walk->flags |= BLKCIPHER_WALK_COPY;
+ if (!walk->page) {
+ walk->page = (void *)__get_free_page(GFP_ATOMIC);
+ if (!walk->page)
+ n = 0;
+ }
+ }
+
+ n = scatterwalk_clamp(&walk->in, n);
+ n = scatterwalk_clamp(&walk->out, n);
+
+ if (unlikely(n < bsize)) {
+ err = blkcipher_next_slow(desc, walk, bsize, alignmask);
+ goto set_phys_lowmem;
+ }
+
+ walk->nbytes = n;
+ if (walk->flags & BLKCIPHER_WALK_COPY) {
+ err = blkcipher_next_copy(walk);
+ goto set_phys_lowmem;
+ }
+
+ return blkcipher_next_fast(desc, walk);
+
+set_phys_lowmem:
+ if (walk->flags & BLKCIPHER_WALK_PHYS) {
+ walk->src.phys.page = virt_to_page(walk->src.virt.addr);
+ walk->dst.phys.page = virt_to_page(walk->dst.virt.addr);
+ walk->src.phys.offset &= PAGE_SIZE - 1;
+ walk->dst.phys.offset &= PAGE_SIZE - 1;
+ }
+ return err;
+}
+
+static inline int blkcipher_copy_iv(struct blkcipher_walk *walk,
+ struct crypto_blkcipher *tfm,
+ unsigned int alignmask)
+{
+ unsigned bs = crypto_blkcipher_blocksize(tfm);
+ unsigned int ivsize = crypto_blkcipher_ivsize(tfm);
+ unsigned int size = bs * 2 + ivsize + max(bs, ivsize) - (alignmask + 1);
+ u8 *iv;
+
+ size += alignmask & ~(crypto_tfm_ctx_alignment() - 1);
+ walk->buffer = kmalloc(size, GFP_ATOMIC);
+ if (!walk->buffer)
+ return -ENOMEM;
+
+ iv = (u8 *)ALIGN((unsigned long)walk->buffer, alignmask + 1);
+ iv = blkcipher_get_spot(iv, bs) + bs;
+ iv = blkcipher_get_spot(iv, bs) + bs;
+ iv = blkcipher_get_spot(iv, ivsize);
+
+ walk->iv = memcpy(iv, walk->iv, ivsize);
+ return 0;
+}
+
+int blkcipher_walk_virt(struct blkcipher_desc *desc,
+ struct blkcipher_walk *walk)
+{
+ walk->flags &= ~BLKCIPHER_WALK_PHYS;
+ return blkcipher_walk_first(desc, walk);
+}
+EXPORT_SYMBOL_GPL(blkcipher_walk_virt);
+
+int blkcipher_walk_phys(struct blkcipher_desc *desc,
+ struct blkcipher_walk *walk)
+{
+ walk->flags |= BLKCIPHER_WALK_PHYS;
+ return blkcipher_walk_first(desc, walk);
+}
+EXPORT_SYMBOL_GPL(blkcipher_walk_phys);
+
+static int blkcipher_walk_first(struct blkcipher_desc *desc,
+ struct blkcipher_walk *walk)
+{
+ struct crypto_blkcipher *tfm = desc->tfm;
+ unsigned int alignmask = crypto_blkcipher_alignmask(tfm);
+
+ walk->nbytes = walk->total;
+ if (unlikely(!walk->total))
+ return 0;
+
+ walk->buffer = NULL;
+ walk->iv = desc->info;
+ if (unlikely(((unsigned long)walk->iv & alignmask))) {
+ int err = blkcipher_copy_iv(walk, tfm, alignmask);
+ if (err)
+ return err;
+ }
+
+ scatterwalk_start(&walk->in, walk->in.sg);
+ scatterwalk_start(&walk->out, walk->out.sg);
+ walk->page = NULL;
+
+ return blkcipher_walk_next(desc, walk);
+}
+
+static int setkey(struct crypto_tfm *tfm, const u8 *key,
+ unsigned int keylen)
+{
+ struct blkcipher_alg *cipher = &tfm->__crt_alg->cra_blkcipher;
+
+ if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) {
+ tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
+ return -EINVAL;
+ }
+
+ return cipher->setkey(tfm, key, keylen);
+}
+
+static unsigned int crypto_blkcipher_ctxsize(struct crypto_alg *alg)
+{
+ struct blkcipher_alg *cipher = &alg->cra_blkcipher;
+ unsigned int len = alg->cra_ctxsize;
+
+ if (cipher->ivsize) {
+ len = ALIGN(len, (unsigned long)alg->cra_alignmask + 1);
+ len += cipher->ivsize;
+ }
+
+ return len;
+}
+
+static int crypto_init_blkcipher_ops(struct crypto_tfm *tfm)
+{
+ struct blkcipher_tfm *crt = &tfm->crt_blkcipher;
+ struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
+ unsigned long align = crypto_tfm_alg_alignmask(tfm) + 1;
+ unsigned long addr;
+
+ if (alg->ivsize > PAGE_SIZE / 8)
+ return -EINVAL;
+
+ crt->setkey = setkey;
+ crt->encrypt = alg->encrypt;
+ crt->decrypt = alg->decrypt;
+
+ addr = (unsigned long)crypto_tfm_ctx(tfm);
+ addr = ALIGN(addr, align);
+ addr += ALIGN(tfm->__crt_alg->cra_ctxsize, align);
+ crt->iv = (void *)addr;
+
+ return 0;
+}
+
+static void crypto_blkcipher_show(struct seq_file *m, struct crypto_alg *alg)
+ __attribute_used__;
+static void crypto_blkcipher_show(struct seq_file *m, struct crypto_alg *alg)
+{
+ seq_printf(m, "type : blkcipher\n");
+ seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
+ seq_printf(m, "min keysize : %u\n", alg->cra_blkcipher.min_keysize);
+ seq_printf(m, "max keysize : %u\n", alg->cra_blkcipher.max_keysize);
+ seq_printf(m, "ivsize : %u\n", alg->cra_blkcipher.ivsize);
+}
+
+const struct crypto_type crypto_blkcipher_type = {
+ .ctxsize = crypto_blkcipher_ctxsize,
+ .init = crypto_init_blkcipher_ops,
+#ifdef CONFIG_PROC_FS
+ .show = crypto_blkcipher_show,
+#endif
+};
+EXPORT_SYMBOL_GPL(crypto_blkcipher_type);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Generic block chaining cipher type");
#define CRYPTO_ALG_TYPE_MASK 0x0000000f
#define CRYPTO_ALG_TYPE_CIPHER 0x00000001
#define CRYPTO_ALG_TYPE_DIGEST 0x00000002
+#define CRYPTO_ALG_TYPE_BLKCIPHER 0x00000003
#define CRYPTO_ALG_TYPE_COMPRESS 0x00000004
#define CRYPTO_ALG_LARVAL 0x00000010
#endif
struct scatterlist;
+struct crypto_blkcipher;
struct crypto_tfm;
struct crypto_type;
+struct blkcipher_desc {
+ struct crypto_blkcipher *tfm;
+ void *info;
+ u32 flags;
+};
+
struct cipher_desc {
struct crypto_tfm *tfm;
void (*crfn)(struct crypto_tfm *tfm, u8 *dst, const u8 *src);
* Algorithms: modular crypto algorithm implementations, managed
* via crypto_register_alg() and crypto_unregister_alg().
*/
+struct blkcipher_alg {
+ int (*setkey)(struct crypto_tfm *tfm, const u8 *key,
+ unsigned int keylen);
+ int (*encrypt)(struct blkcipher_desc *desc,
+ struct scatterlist *dst, struct scatterlist *src,
+ unsigned int nbytes);
+ int (*decrypt)(struct blkcipher_desc *desc,
+ struct scatterlist *dst, struct scatterlist *src,
+ unsigned int nbytes);
+
+ unsigned int min_keysize;
+ unsigned int max_keysize;
+ unsigned int ivsize;
+};
+
struct cipher_alg {
unsigned int cia_min_keysize;
unsigned int cia_max_keysize;
unsigned int slen, u8 *dst, unsigned int *dlen);
};
+#define cra_blkcipher cra_u.blkcipher
#define cra_cipher cra_u.cipher
#define cra_digest cra_u.digest
#define cra_compress cra_u.compress
const struct crypto_type *cra_type;
union {
+ struct blkcipher_alg blkcipher;
struct cipher_alg cipher;
struct digest_alg digest;
struct compress_alg compress;
* crypto_free_*(), as well as the various helpers below.
*/
+struct blkcipher_tfm {
+ void *iv;
+ int (*setkey)(struct crypto_tfm *tfm, const u8 *key,
+ unsigned int keylen);
+ int (*encrypt)(struct blkcipher_desc *desc, struct scatterlist *dst,
+ struct scatterlist *src, unsigned int nbytes);
+ int (*decrypt)(struct blkcipher_desc *desc, struct scatterlist *dst,
+ struct scatterlist *src, unsigned int nbytes);
+};
+
struct cipher_tfm {
void *cit_iv;
unsigned int cit_ivsize;
u8 *dst, unsigned int *dlen);
};
+#define crt_blkcipher crt_u.blkcipher
#define crt_cipher crt_u.cipher
#define crt_digest crt_u.digest
#define crt_compress crt_u.compress
u32 crt_flags;
union {
+ struct blkcipher_tfm blkcipher;
struct cipher_tfm cipher;
struct digest_tfm digest;
struct compress_tfm compress;
#define crypto_cipher crypto_tfm
+struct crypto_blkcipher {
+ struct crypto_tfm base;
+};
+
enum {
CRYPTOA_UNSPEC,
CRYPTOA_ALG,
/*
* API wrappers.
*/
+static inline struct crypto_blkcipher *__crypto_blkcipher_cast(
+ struct crypto_tfm *tfm)
+{
+ return (struct crypto_blkcipher *)tfm;
+}
+
+static inline struct crypto_blkcipher *crypto_blkcipher_cast(
+ struct crypto_tfm *tfm)
+{
+ BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_BLKCIPHER);
+ return __crypto_blkcipher_cast(tfm);
+}
+
+static inline struct crypto_blkcipher *crypto_alloc_blkcipher(
+ const char *alg_name, u32 type, u32 mask)
+{
+ type &= ~CRYPTO_ALG_TYPE_MASK;
+ type |= CRYPTO_ALG_TYPE_BLKCIPHER;
+ mask |= CRYPTO_ALG_TYPE_MASK;
+
+ return __crypto_blkcipher_cast(crypto_alloc_base(alg_name, type, mask));
+}
+
+static inline struct crypto_tfm *crypto_blkcipher_tfm(
+ struct crypto_blkcipher *tfm)
+{
+ return &tfm->base;
+}
+
+static inline void crypto_free_blkcipher(struct crypto_blkcipher *tfm)
+{
+ crypto_free_tfm(crypto_blkcipher_tfm(tfm));
+}
+
+static inline const char *crypto_blkcipher_name(struct crypto_blkcipher *tfm)
+{
+ return crypto_tfm_alg_name(crypto_blkcipher_tfm(tfm));
+}
+
+static inline struct blkcipher_tfm *crypto_blkcipher_crt(
+ struct crypto_blkcipher *tfm)
+{
+ return &crypto_blkcipher_tfm(tfm)->crt_blkcipher;
+}
+
+static inline struct blkcipher_alg *crypto_blkcipher_alg(
+ struct crypto_blkcipher *tfm)
+{
+ return &crypto_blkcipher_tfm(tfm)->__crt_alg->cra_blkcipher;
+}
+
+static inline unsigned int crypto_blkcipher_ivsize(struct crypto_blkcipher *tfm)
+{
+ return crypto_blkcipher_alg(tfm)->ivsize;
+}
+
+static inline unsigned int crypto_blkcipher_blocksize(
+ struct crypto_blkcipher *tfm)
+{
+ return crypto_tfm_alg_blocksize(crypto_blkcipher_tfm(tfm));
+}
+
+static inline unsigned int crypto_blkcipher_alignmask(
+ struct crypto_blkcipher *tfm)
+{
+ return crypto_tfm_alg_alignmask(crypto_blkcipher_tfm(tfm));
+}
+
+static inline u32 crypto_blkcipher_get_flags(struct crypto_blkcipher *tfm)
+{
+ return crypto_tfm_get_flags(crypto_blkcipher_tfm(tfm));
+}
+
+static inline void crypto_blkcipher_set_flags(struct crypto_blkcipher *tfm,
+ u32 flags)
+{
+ crypto_tfm_set_flags(crypto_blkcipher_tfm(tfm), flags);
+}
+
+static inline void crypto_blkcipher_clear_flags(struct crypto_blkcipher *tfm,
+ u32 flags)
+{
+ crypto_tfm_clear_flags(crypto_blkcipher_tfm(tfm), flags);
+}
+
+static inline int crypto_blkcipher_setkey(struct crypto_blkcipher *tfm,
+ const u8 *key, unsigned int keylen)
+{
+ return crypto_blkcipher_crt(tfm)->setkey(crypto_blkcipher_tfm(tfm),
+ key, keylen);
+}
+
+static inline int crypto_blkcipher_encrypt(struct blkcipher_desc *desc,
+ struct scatterlist *dst,
+ struct scatterlist *src,
+ unsigned int nbytes)
+{
+ desc->info = crypto_blkcipher_crt(desc->tfm)->iv;
+ return crypto_blkcipher_crt(desc->tfm)->encrypt(desc, dst, src, nbytes);
+}
+
+static inline int crypto_blkcipher_encrypt_iv(struct blkcipher_desc *desc,
+ struct scatterlist *dst,
+ struct scatterlist *src,
+ unsigned int nbytes)
+{
+ return crypto_blkcipher_crt(desc->tfm)->encrypt(desc, dst, src, nbytes);
+}
+
+static inline int crypto_blkcipher_decrypt(struct blkcipher_desc *desc,
+ struct scatterlist *dst,
+ struct scatterlist *src,
+ unsigned int nbytes)
+{
+ desc->info = crypto_blkcipher_crt(desc->tfm)->iv;
+ return crypto_blkcipher_crt(desc->tfm)->decrypt(desc, dst, src, nbytes);
+}
+
+static inline int crypto_blkcipher_decrypt_iv(struct blkcipher_desc *desc,
+ struct scatterlist *dst,
+ struct scatterlist *src,
+ unsigned int nbytes)
+{
+ return crypto_blkcipher_crt(desc->tfm)->decrypt(desc, dst, src, nbytes);
+}
+
+static inline void crypto_blkcipher_set_iv(struct crypto_blkcipher *tfm,
+ const u8 *src, unsigned int len)
+{
+ memcpy(crypto_blkcipher_crt(tfm)->iv, src, len);
+}
+
+static inline void crypto_blkcipher_get_iv(struct crypto_blkcipher *tfm,
+ u8 *dst, unsigned int len)
+{
+ memcpy(dst, crypto_blkcipher_crt(tfm)->iv, len);
+}
+
static inline struct crypto_cipher *__crypto_cipher_cast(struct crypto_tfm *tfm)
{
return (struct crypto_cipher *)tfm;
projects / linux-2.6 / commitdiff