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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /arch/x86/crypto/ecb_cbc_helpers.h
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/crypto/ecb_cbc_helpers.h')
-rw-r--r--arch/x86/crypto/ecb_cbc_helpers.h76
1 files changed, 76 insertions, 0 deletions
diff --git a/arch/x86/crypto/ecb_cbc_helpers.h b/arch/x86/crypto/ecb_cbc_helpers.h
new file mode 100644
index 000000000..eaa15c7b2
--- /dev/null
+++ b/arch/x86/crypto/ecb_cbc_helpers.h
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+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _CRYPTO_ECB_CBC_HELPER_H
+#define _CRYPTO_ECB_CBC_HELPER_H
+
+#include <crypto/internal/skcipher.h>
+#include <asm/fpu/api.h>
+
+/*
+ * Mode helpers to instantiate parameterized skcipher ECB/CBC modes without
+ * having to rely on indirect calls and retpolines.
+ */
+
+#define ECB_WALK_START(req, bsize, fpu_blocks) do { \
+ void *ctx = crypto_skcipher_ctx(crypto_skcipher_reqtfm(req)); \
+ const int __bsize = (bsize); \
+ struct skcipher_walk walk; \
+ int err = skcipher_walk_virt(&walk, (req), false); \
+ while (walk.nbytes > 0) { \
+ unsigned int nbytes = walk.nbytes; \
+ bool do_fpu = (fpu_blocks) != -1 && \
+ nbytes >= (fpu_blocks) * __bsize; \
+ const u8 *src = walk.src.virt.addr; \
+ u8 *dst = walk.dst.virt.addr; \
+ u8 __maybe_unused buf[(bsize)]; \
+ if (do_fpu) kernel_fpu_begin()
+
+#define CBC_WALK_START(req, bsize, fpu_blocks) \
+ ECB_WALK_START(req, bsize, fpu_blocks)
+
+#define ECB_WALK_ADVANCE(blocks) do { \
+ dst += (blocks) * __bsize; \
+ src += (blocks) * __bsize; \
+ nbytes -= (blocks) * __bsize; \
+} while (0)
+
+#define ECB_BLOCK(blocks, func) do { \
+ while (nbytes >= (blocks) * __bsize) { \
+ (func)(ctx, dst, src); \
+ ECB_WALK_ADVANCE(blocks); \
+ } \
+} while (0)
+
+#define CBC_ENC_BLOCK(func) do { \
+ const u8 *__iv = walk.iv; \
+ while (nbytes >= __bsize) { \
+ crypto_xor_cpy(dst, src, __iv, __bsize); \
+ (func)(ctx, dst, dst); \
+ __iv = dst; \
+ ECB_WALK_ADVANCE(1); \
+ } \
+ memcpy(walk.iv, __iv, __bsize); \
+} while (0)
+
+#define CBC_DEC_BLOCK(blocks, func) do { \
+ while (nbytes >= (blocks) * __bsize) { \
+ const u8 *__iv = src + ((blocks) - 1) * __bsize; \
+ if (dst == src) \
+ __iv = memcpy(buf, __iv, __bsize); \
+ (func)(ctx, dst, src); \
+ crypto_xor(dst, walk.iv, __bsize); \
+ memcpy(walk.iv, __iv, __bsize); \
+ ECB_WALK_ADVANCE(blocks); \
+ } \
+} while (0)
+
+#define ECB_WALK_END() \
+ if (do_fpu) kernel_fpu_end(); \
+ err = skcipher_walk_done(&walk, nbytes); \
+ } \
+ return err; \
+} while (0)
+
+#define CBC_WALK_END() ECB_WALK_END()
+
+#endif