| 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
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| 2 | |
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| 3 | #ifndef _CRYPTO_ECB_CBC_HELPER_H |
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| 4 | #define _CRYPTO_ECB_CBC_HELPER_H |
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| 5 | |
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| 6 | #include <crypto/internal/skcipher.h> |
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| 7 | #include <asm/fpu/api.h> |
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| 8 | |
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| 9 | /* |
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| 10 | * Mode helpers to instantiate parameterized skcipher ECB/CBC modes without |
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| 11 | * having to rely on indirect calls and retpolines. |
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| 12 | */ |
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| 13 | |
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| 14 | #define ECB_WALK_START(req, bsize, fpu_blocks) do { \ |
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| 15 | void *ctx = crypto_skcipher_ctx(crypto_skcipher_reqtfm(req)); \ |
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| 16 | const int __fpu_blocks = (fpu_blocks); \ |
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| 17 | const int __bsize = (bsize); \ |
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| 18 | struct skcipher_walk walk; \ |
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| 19 | int err = skcipher_walk_virt(&walk, (req), false); \ |
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| 20 | while (walk.nbytes > 0) { \ |
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| 21 | unsigned int nbytes = walk.nbytes; \ |
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| 22 | bool do_fpu = __fpu_blocks != -1 && \ |
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| 23 | nbytes >= __fpu_blocks * __bsize; \ |
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| 24 | const u8 *src = walk.src.virt.addr; \ |
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| 25 | u8 *dst = walk.dst.virt.addr; \ |
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| 26 | u8 __maybe_unused buf[(bsize)]; \ |
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| 27 | if (do_fpu) kernel_fpu_begin() |
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| 28 | |
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| 29 | #define CBC_WALK_START(req, bsize, fpu_blocks) \ |
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| 30 | ECB_WALK_START(req, bsize, fpu_blocks) |
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| 31 | |
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| 32 | #define ECB_WALK_ADVANCE(blocks) do { \ |
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| 33 | dst += (blocks) * __bsize; \ |
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| 34 | src += (blocks) * __bsize; \ |
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| 35 | nbytes -= (blocks) * __bsize; \ |
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| 36 | } while (0) |
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| 37 | |
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| 38 | #define ECB_BLOCK(blocks, func) do { \ |
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| 39 | const int __blocks = (blocks); \ |
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| 40 | if (do_fpu && __blocks < __fpu_blocks) { \ |
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| 41 | kernel_fpu_end(); \ |
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| 42 | do_fpu = false; \ |
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| 43 | } \ |
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| 44 | while (nbytes >= __blocks * __bsize) { \ |
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| 45 | (func)(ctx, dst, src); \ |
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| 46 | ECB_WALK_ADVANCE(blocks); \ |
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| 47 | } \ |
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| 48 | } while (0) |
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| 49 | |
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| 50 | #define CBC_ENC_BLOCK(func) do { \ |
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| 51 | const u8 *__iv = walk.iv; \ |
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| 52 | while (nbytes >= __bsize) { \ |
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| 53 | crypto_xor_cpy(dst, src, __iv, __bsize); \ |
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| 54 | (func)(ctx, dst, dst); \ |
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| 55 | __iv = dst; \ |
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| 56 | ECB_WALK_ADVANCE(1); \ |
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| 57 | } \ |
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| 58 | memcpy(walk.iv, __iv, __bsize); \ |
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| 59 | } while (0) |
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| 60 | |
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| 61 | #define CBC_DEC_BLOCK(blocks, func) do { \ |
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| 62 | const int __blocks = (blocks); \ |
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| 63 | if (do_fpu && __blocks < __fpu_blocks) { \ |
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| 64 | kernel_fpu_end(); \ |
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| 65 | do_fpu = false; \ |
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| 66 | } \ |
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| 67 | while (nbytes >= __blocks * __bsize) { \ |
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| 68 | const u8 *__iv = src + ((blocks) - 1) * __bsize; \ |
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| 69 | if (dst == src) \ |
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| 70 | __iv = memcpy(buf, __iv, __bsize); \ |
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| 71 | (func)(ctx, dst, src); \ |
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| 72 | crypto_xor(dst, walk.iv, __bsize); \ |
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| 73 | memcpy(walk.iv, __iv, __bsize); \ |
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| 74 | ECB_WALK_ADVANCE(blocks); \ |
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| 75 | } \ |
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| 76 | } while (0) |
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| 77 | |
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| 78 | #define ECB_WALK_END() \ |
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| 79 | if (do_fpu) kernel_fpu_end(); \ |
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| 80 | err = skcipher_walk_done(&walk, nbytes); \ |
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| 81 | } \ |
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| 82 | return err; \ |
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| 83 | } while (0) |
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| 84 | |
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| 85 | #define CBC_WALK_END() ECB_WALK_END() |
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| 86 | |
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| 87 | #endif |
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| 88 | |
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