1 /* SPDX-License-Identifier: GPL-2.0 */ 2 3 #ifndef _CRYPTO_ECB_CBC_HELPER_H 4 #define _CRYPTO_ECB_CBC_HELPER_H 5 6 #include <crypto/internal/skcipher.h> 7 #include <asm/fpu/api.h> 8 9 /* 10 * Mode helpers to instantiate parameterized skcipher ECB/CBC modes without 11 * having to rely on indirect calls and retpolines. 12 */ 13 14 #define ECB_WALK_START(req, bsize, fpu_blocks) do { \ 15 void *ctx = crypto_skcipher_ctx(crypto_skcipher_reqtfm(req)); \ 16 const int __bsize = (bsize); \ 17 struct skcipher_walk walk; \ 18 int err = skcipher_walk_virt(&walk, (req), false); \ 19 while (walk.nbytes > 0) { \ 20 unsigned int nbytes = walk.nbytes; \ 21 bool do_fpu = (fpu_blocks) != -1 && \ 22 nbytes >= (fpu_blocks) * __bsize; \ 23 const u8 *src = walk.src.virt.addr; \ 24 u8 *dst = walk.dst.virt.addr; \ 25 u8 __maybe_unused buf[(bsize)]; \ 26 if (do_fpu) kernel_fpu_begin() 27 28 #define CBC_WALK_START(req, bsize, fpu_blocks) \ 29 ECB_WALK_START(req, bsize, fpu_blocks) 30 31 #define ECB_WALK_ADVANCE(blocks) do { \ 32 dst += (blocks) * __bsize; \ 33 src += (blocks) * __bsize; \ 34 nbytes -= (blocks) * __bsize; \ 35 } while (0) 36 37 #define ECB_BLOCK(blocks, func) do { \ 38 while (nbytes >= (blocks) * __bsize) { \ 39 (func)(ctx, dst, src); \ 40 ECB_WALK_ADVANCE(blocks); \ 41 } \ 42 } while (0) 43 44 #define CBC_ENC_BLOCK(func) do { \ 45 const u8 *__iv = walk.iv; \ 46 while (nbytes >= __bsize) { \ 47 crypto_xor_cpy(dst, src, __iv, __bsize); \ 48 (func)(ctx, dst, dst); \ 49 __iv = dst; \ 50 ECB_WALK_ADVANCE(1); \ 51 } \ 52 memcpy(walk.iv, __iv, __bsize); \ 53 } while (0) 54 55 #define CBC_DEC_BLOCK(blocks, func) do { \ 56 while (nbytes >= (blocks) * __bsize) { \ 57 const u8 *__iv = src + ((blocks) - 1) * __bsize; \ 58 if (dst == src) \ 59 __iv = memcpy(buf, __iv, __bsize); \ 60 (func)(ctx, dst, src); \ 61 crypto_xor(dst, walk.iv, __bsize); \ 62 memcpy(walk.iv, __iv, __bsize); \ 63 ECB_WALK_ADVANCE(blocks); \ 64 } \ 65 } while (0) 66 67 #define ECB_WALK_END() \ 68 if (do_fpu) kernel_fpu_end(); \ 69 err = skcipher_walk_done(&walk, nbytes); \ 70 } \ 71 return err; \ 72 } while (0) 73 74 #define CBC_WALK_END() ECB_WALK_END() 75 76 #endif 77