Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wirel...

[karo-tx-linux.git] / arch / x86 / crypto / glue_helper.c

diff --git a/arch/x86/crypto/glue_helper.c b/arch/x86/crypto/glue_helper.c
index 22ce4f683e550da4b464c99d8fedfce6414ea885..432f1d76ceb827f9d356c9a86b50b87d60c4ce09 100644 (file)
--- a/arch/x86/crypto/glue_helper.c
+++ b/arch/x86/crypto/glue_helper.c
@@ -1,7 +1,7 @@
 /*
  * Shared glue code for 128bit block ciphers
  *
- * Copyright (c) 2012 Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
+ * Copyright © 2012-2013 Jussi Kivilinna <jussi.kivilinna@iki.fi>
  *
  * CBC & ECB parts based on code (crypto/cbc.c,ecb.c) by:
  *   Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
@@ -304,4 +304,99 @@ int glue_ctr_crypt_128bit(const struct common_glue_ctx *gctx,
 }
 EXPORT_SYMBOL_GPL(glue_ctr_crypt_128bit);
 
+static unsigned int __glue_xts_crypt_128bit(const struct common_glue_ctx *gctx,
+                                           void *ctx,
+                                           struct blkcipher_desc *desc,
+                                           struct blkcipher_walk *walk)
+{
+       const unsigned int bsize = 128 / 8;
+       unsigned int nbytes = walk->nbytes;
+       u128 *src = (u128 *)walk->src.virt.addr;
+       u128 *dst = (u128 *)walk->dst.virt.addr;
+       unsigned int num_blocks, func_bytes;
+       unsigned int i;
+
+       /* Process multi-block batch */
+       for (i = 0; i < gctx->num_funcs; i++) {
+               num_blocks = gctx->funcs[i].num_blocks;
+               func_bytes = bsize * num_blocks;
+
+               if (nbytes >= func_bytes) {
+                       do {
+                               gctx->funcs[i].fn_u.xts(ctx, dst, src,
+                                                       (le128 *)walk->iv);
+
+                               src += num_blocks;
+                               dst += num_blocks;
+                               nbytes -= func_bytes;
+                       } while (nbytes >= func_bytes);
+
+                       if (nbytes < bsize)
+                               goto done;
+               }
+       }
+
+done:
+       return nbytes;
+}
+
+/* for implementations implementing faster XTS IV generator */
+int glue_xts_crypt_128bit(const struct common_glue_ctx *gctx,
+                         struct blkcipher_desc *desc, struct scatterlist *dst,
+                         struct scatterlist *src, unsigned int nbytes,
+                         void (*tweak_fn)(void *ctx, u8 *dst, const u8 *src),
+                         void *tweak_ctx, void *crypt_ctx)
+{
+       const unsigned int bsize = 128 / 8;
+       bool fpu_enabled = false;
+       struct blkcipher_walk walk;
+       int err;
+
+       blkcipher_walk_init(&walk, dst, src, nbytes);
+
+       err = blkcipher_walk_virt(desc, &walk);
+       nbytes = walk.nbytes;
+       if (!nbytes)
+               return err;
+
+       /* set minimum length to bsize, for tweak_fn */
+       fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
+                                    desc, fpu_enabled,
+                                    nbytes < bsize ? bsize : nbytes);
+
+       /* calculate first value of T */
+       tweak_fn(tweak_ctx, walk.iv, walk.iv);
+
+       while (nbytes) {
+               nbytes = __glue_xts_crypt_128bit(gctx, crypt_ctx, desc, &walk);
+
+               err = blkcipher_walk_done(desc, &walk, nbytes);
+               nbytes = walk.nbytes;
+       }
+
+       glue_fpu_end(fpu_enabled);
+
+       return err;
+}
+EXPORT_SYMBOL_GPL(glue_xts_crypt_128bit);
+
+void glue_xts_crypt_128bit_one(void *ctx, u128 *dst, const u128 *src, le128 *iv,
+                              common_glue_func_t fn)
+{
+       le128 ivblk = *iv;
+
+       /* generate next IV */
+       le128_gf128mul_x_ble(iv, &ivblk);
+
+       /* CC <- T xor C */
+       u128_xor(dst, src, (u128 *)&ivblk);
+
+       /* PP <- D(Key2,CC) */
+       fn(ctx, (u8 *)dst, (u8 *)dst);
+
+       /* P <- T xor PP */
+       u128_xor(dst, dst, (u128 *)&ivblk);
+}
+EXPORT_SYMBOL_GPL(glue_xts_crypt_128bit_one);
+
 MODULE_LICENSE("GPL");