.. | .. |
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| 1 | +// SPDX-License-Identifier: GPL-2.0-only |
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1 | 2 | /* |
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2 | 3 | * Scalar fixed time AES core transform |
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3 | 4 | * |
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4 | 5 | * Copyright (C) 2017 Linaro Ltd <ard.biesheuvel@linaro.org> |
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5 | | - * |
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6 | | - * This program is free software; you can redistribute it and/or modify |
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7 | | - * it under the terms of the GNU General Public License version 2 as |
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8 | | - * published by the Free Software Foundation. |
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9 | 6 | */ |
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10 | 7 | |
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11 | 8 | #include <crypto/aes.h> |
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12 | 9 | #include <linux/crypto.h> |
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13 | 10 | #include <linux/module.h> |
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14 | | -#include <asm/unaligned.h> |
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15 | | - |
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16 | | -/* |
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17 | | - * Emit the sbox as volatile const to prevent the compiler from doing |
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18 | | - * constant folding on sbox references involving fixed indexes. |
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19 | | - */ |
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20 | | -static volatile const u8 __cacheline_aligned __aesti_sbox[] = { |
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21 | | - 0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, |
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22 | | - 0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76, |
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23 | | - 0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0, |
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24 | | - 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0, |
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25 | | - 0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc, |
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26 | | - 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15, |
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27 | | - 0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, |
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28 | | - 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75, |
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29 | | - 0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, |
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30 | | - 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84, |
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31 | | - 0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b, |
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32 | | - 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf, |
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33 | | - 0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, |
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34 | | - 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8, |
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35 | | - 0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, |
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36 | | - 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2, |
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37 | | - 0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17, |
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38 | | - 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73, |
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39 | | - 0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, |
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40 | | - 0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb, |
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41 | | - 0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c, |
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42 | | - 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79, |
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43 | | - 0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9, |
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44 | | - 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08, |
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45 | | - 0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6, |
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46 | | - 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a, |
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47 | | - 0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e, |
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48 | | - 0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e, |
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49 | | - 0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94, |
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50 | | - 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf, |
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51 | | - 0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, |
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52 | | - 0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16, |
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53 | | -}; |
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54 | | - |
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55 | | -static volatile const u8 __cacheline_aligned __aesti_inv_sbox[] = { |
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56 | | - 0x52, 0x09, 0x6a, 0xd5, 0x30, 0x36, 0xa5, 0x38, |
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57 | | - 0xbf, 0x40, 0xa3, 0x9e, 0x81, 0xf3, 0xd7, 0xfb, |
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58 | | - 0x7c, 0xe3, 0x39, 0x82, 0x9b, 0x2f, 0xff, 0x87, |
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59 | | - 0x34, 0x8e, 0x43, 0x44, 0xc4, 0xde, 0xe9, 0xcb, |
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60 | | - 0x54, 0x7b, 0x94, 0x32, 0xa6, 0xc2, 0x23, 0x3d, |
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61 | | - 0xee, 0x4c, 0x95, 0x0b, 0x42, 0xfa, 0xc3, 0x4e, |
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62 | | - 0x08, 0x2e, 0xa1, 0x66, 0x28, 0xd9, 0x24, 0xb2, |
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63 | | - 0x76, 0x5b, 0xa2, 0x49, 0x6d, 0x8b, 0xd1, 0x25, |
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64 | | - 0x72, 0xf8, 0xf6, 0x64, 0x86, 0x68, 0x98, 0x16, |
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65 | | - 0xd4, 0xa4, 0x5c, 0xcc, 0x5d, 0x65, 0xb6, 0x92, |
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66 | | - 0x6c, 0x70, 0x48, 0x50, 0xfd, 0xed, 0xb9, 0xda, |
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67 | | - 0x5e, 0x15, 0x46, 0x57, 0xa7, 0x8d, 0x9d, 0x84, |
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68 | | - 0x90, 0xd8, 0xab, 0x00, 0x8c, 0xbc, 0xd3, 0x0a, |
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69 | | - 0xf7, 0xe4, 0x58, 0x05, 0xb8, 0xb3, 0x45, 0x06, |
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70 | | - 0xd0, 0x2c, 0x1e, 0x8f, 0xca, 0x3f, 0x0f, 0x02, |
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71 | | - 0xc1, 0xaf, 0xbd, 0x03, 0x01, 0x13, 0x8a, 0x6b, |
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72 | | - 0x3a, 0x91, 0x11, 0x41, 0x4f, 0x67, 0xdc, 0xea, |
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73 | | - 0x97, 0xf2, 0xcf, 0xce, 0xf0, 0xb4, 0xe6, 0x73, |
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74 | | - 0x96, 0xac, 0x74, 0x22, 0xe7, 0xad, 0x35, 0x85, |
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75 | | - 0xe2, 0xf9, 0x37, 0xe8, 0x1c, 0x75, 0xdf, 0x6e, |
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76 | | - 0x47, 0xf1, 0x1a, 0x71, 0x1d, 0x29, 0xc5, 0x89, |
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77 | | - 0x6f, 0xb7, 0x62, 0x0e, 0xaa, 0x18, 0xbe, 0x1b, |
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78 | | - 0xfc, 0x56, 0x3e, 0x4b, 0xc6, 0xd2, 0x79, 0x20, |
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79 | | - 0x9a, 0xdb, 0xc0, 0xfe, 0x78, 0xcd, 0x5a, 0xf4, |
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80 | | - 0x1f, 0xdd, 0xa8, 0x33, 0x88, 0x07, 0xc7, 0x31, |
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81 | | - 0xb1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xec, 0x5f, |
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82 | | - 0x60, 0x51, 0x7f, 0xa9, 0x19, 0xb5, 0x4a, 0x0d, |
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83 | | - 0x2d, 0xe5, 0x7a, 0x9f, 0x93, 0xc9, 0x9c, 0xef, |
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84 | | - 0xa0, 0xe0, 0x3b, 0x4d, 0xae, 0x2a, 0xf5, 0xb0, |
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85 | | - 0xc8, 0xeb, 0xbb, 0x3c, 0x83, 0x53, 0x99, 0x61, |
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86 | | - 0x17, 0x2b, 0x04, 0x7e, 0xba, 0x77, 0xd6, 0x26, |
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87 | | - 0xe1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0c, 0x7d, |
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88 | | -}; |
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89 | | - |
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90 | | -static u32 mul_by_x(u32 w) |
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91 | | -{ |
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92 | | - u32 x = w & 0x7f7f7f7f; |
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93 | | - u32 y = w & 0x80808080; |
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94 | | - |
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95 | | - /* multiply by polynomial 'x' (0b10) in GF(2^8) */ |
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96 | | - return (x << 1) ^ (y >> 7) * 0x1b; |
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97 | | -} |
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98 | | - |
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99 | | -static u32 mul_by_x2(u32 w) |
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100 | | -{ |
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101 | | - u32 x = w & 0x3f3f3f3f; |
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102 | | - u32 y = w & 0x80808080; |
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103 | | - u32 z = w & 0x40404040; |
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104 | | - |
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105 | | - /* multiply by polynomial 'x^2' (0b100) in GF(2^8) */ |
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106 | | - return (x << 2) ^ (y >> 7) * 0x36 ^ (z >> 6) * 0x1b; |
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107 | | -} |
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108 | | - |
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109 | | -static u32 mix_columns(u32 x) |
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110 | | -{ |
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111 | | - /* |
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112 | | - * Perform the following matrix multiplication in GF(2^8) |
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113 | | - * |
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114 | | - * | 0x2 0x3 0x1 0x1 | | x[0] | |
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115 | | - * | 0x1 0x2 0x3 0x1 | | x[1] | |
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116 | | - * | 0x1 0x1 0x2 0x3 | x | x[2] | |
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117 | | - * | 0x3 0x1 0x1 0x2 | | x[3] | |
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118 | | - */ |
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119 | | - u32 y = mul_by_x(x) ^ ror32(x, 16); |
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120 | | - |
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121 | | - return y ^ ror32(x ^ y, 8); |
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122 | | -} |
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123 | | - |
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124 | | -static u32 inv_mix_columns(u32 x) |
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125 | | -{ |
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126 | | - /* |
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127 | | - * Perform the following matrix multiplication in GF(2^8) |
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128 | | - * |
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129 | | - * | 0xe 0xb 0xd 0x9 | | x[0] | |
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130 | | - * | 0x9 0xe 0xb 0xd | | x[1] | |
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131 | | - * | 0xd 0x9 0xe 0xb | x | x[2] | |
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132 | | - * | 0xb 0xd 0x9 0xe | | x[3] | |
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133 | | - * |
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134 | | - * which can conveniently be reduced to |
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135 | | - * |
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136 | | - * | 0x2 0x3 0x1 0x1 | | 0x5 0x0 0x4 0x0 | | x[0] | |
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137 | | - * | 0x1 0x2 0x3 0x1 | | 0x0 0x5 0x0 0x4 | | x[1] | |
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138 | | - * | 0x1 0x1 0x2 0x3 | x | 0x4 0x0 0x5 0x0 | x | x[2] | |
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139 | | - * | 0x3 0x1 0x1 0x2 | | 0x0 0x4 0x0 0x5 | | x[3] | |
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140 | | - */ |
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141 | | - u32 y = mul_by_x2(x); |
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142 | | - |
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143 | | - return mix_columns(x ^ y ^ ror32(y, 16)); |
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144 | | -} |
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145 | | - |
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146 | | -static __always_inline u32 subshift(u32 in[], int pos) |
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147 | | -{ |
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148 | | - return (__aesti_sbox[in[pos] & 0xff]) ^ |
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149 | | - (__aesti_sbox[(in[(pos + 1) % 4] >> 8) & 0xff] << 8) ^ |
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150 | | - (__aesti_sbox[(in[(pos + 2) % 4] >> 16) & 0xff] << 16) ^ |
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151 | | - (__aesti_sbox[(in[(pos + 3) % 4] >> 24) & 0xff] << 24); |
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152 | | -} |
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153 | | - |
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154 | | -static __always_inline u32 inv_subshift(u32 in[], int pos) |
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155 | | -{ |
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156 | | - return (__aesti_inv_sbox[in[pos] & 0xff]) ^ |
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157 | | - (__aesti_inv_sbox[(in[(pos + 3) % 4] >> 8) & 0xff] << 8) ^ |
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158 | | - (__aesti_inv_sbox[(in[(pos + 2) % 4] >> 16) & 0xff] << 16) ^ |
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159 | | - (__aesti_inv_sbox[(in[(pos + 1) % 4] >> 24) & 0xff] << 24); |
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160 | | -} |
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161 | | - |
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162 | | -static u32 subw(u32 in) |
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163 | | -{ |
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164 | | - return (__aesti_sbox[in & 0xff]) ^ |
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165 | | - (__aesti_sbox[(in >> 8) & 0xff] << 8) ^ |
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166 | | - (__aesti_sbox[(in >> 16) & 0xff] << 16) ^ |
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167 | | - (__aesti_sbox[(in >> 24) & 0xff] << 24); |
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168 | | -} |
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169 | | - |
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170 | | -static int aesti_expand_key(struct crypto_aes_ctx *ctx, const u8 *in_key, |
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171 | | - unsigned int key_len) |
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172 | | -{ |
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173 | | - u32 kwords = key_len / sizeof(u32); |
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174 | | - u32 rc, i, j; |
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175 | | - |
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176 | | - if (key_len != AES_KEYSIZE_128 && |
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177 | | - key_len != AES_KEYSIZE_192 && |
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178 | | - key_len != AES_KEYSIZE_256) |
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179 | | - return -EINVAL; |
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180 | | - |
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181 | | - ctx->key_length = key_len; |
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182 | | - |
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183 | | - for (i = 0; i < kwords; i++) |
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184 | | - ctx->key_enc[i] = get_unaligned_le32(in_key + i * sizeof(u32)); |
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185 | | - |
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186 | | - for (i = 0, rc = 1; i < 10; i++, rc = mul_by_x(rc)) { |
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187 | | - u32 *rki = ctx->key_enc + (i * kwords); |
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188 | | - u32 *rko = rki + kwords; |
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189 | | - |
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190 | | - rko[0] = ror32(subw(rki[kwords - 1]), 8) ^ rc ^ rki[0]; |
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191 | | - rko[1] = rko[0] ^ rki[1]; |
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192 | | - rko[2] = rko[1] ^ rki[2]; |
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193 | | - rko[3] = rko[2] ^ rki[3]; |
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194 | | - |
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195 | | - if (key_len == 24) { |
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196 | | - if (i >= 7) |
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197 | | - break; |
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198 | | - rko[4] = rko[3] ^ rki[4]; |
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199 | | - rko[5] = rko[4] ^ rki[5]; |
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200 | | - } else if (key_len == 32) { |
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201 | | - if (i >= 6) |
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202 | | - break; |
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203 | | - rko[4] = subw(rko[3]) ^ rki[4]; |
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204 | | - rko[5] = rko[4] ^ rki[5]; |
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205 | | - rko[6] = rko[5] ^ rki[6]; |
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206 | | - rko[7] = rko[6] ^ rki[7]; |
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207 | | - } |
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208 | | - } |
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209 | | - |
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210 | | - /* |
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211 | | - * Generate the decryption keys for the Equivalent Inverse Cipher. |
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212 | | - * This involves reversing the order of the round keys, and applying |
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213 | | - * the Inverse Mix Columns transformation to all but the first and |
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214 | | - * the last one. |
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215 | | - */ |
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216 | | - ctx->key_dec[0] = ctx->key_enc[key_len + 24]; |
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217 | | - ctx->key_dec[1] = ctx->key_enc[key_len + 25]; |
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218 | | - ctx->key_dec[2] = ctx->key_enc[key_len + 26]; |
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219 | | - ctx->key_dec[3] = ctx->key_enc[key_len + 27]; |
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220 | | - |
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221 | | - for (i = 4, j = key_len + 20; j > 0; i += 4, j -= 4) { |
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222 | | - ctx->key_dec[i] = inv_mix_columns(ctx->key_enc[j]); |
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223 | | - ctx->key_dec[i + 1] = inv_mix_columns(ctx->key_enc[j + 1]); |
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224 | | - ctx->key_dec[i + 2] = inv_mix_columns(ctx->key_enc[j + 2]); |
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225 | | - ctx->key_dec[i + 3] = inv_mix_columns(ctx->key_enc[j + 3]); |
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226 | | - } |
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227 | | - |
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228 | | - ctx->key_dec[i] = ctx->key_enc[0]; |
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229 | | - ctx->key_dec[i + 1] = ctx->key_enc[1]; |
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230 | | - ctx->key_dec[i + 2] = ctx->key_enc[2]; |
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231 | | - ctx->key_dec[i + 3] = ctx->key_enc[3]; |
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232 | | - |
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233 | | - return 0; |
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234 | | -} |
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235 | 11 | |
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236 | 12 | static int aesti_set_key(struct crypto_tfm *tfm, const u8 *in_key, |
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237 | 13 | unsigned int key_len) |
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238 | 14 | { |
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239 | 15 | struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm); |
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240 | | - int err; |
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241 | 16 | |
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242 | | - err = aesti_expand_key(ctx, in_key, key_len); |
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243 | | - if (err) |
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244 | | - return err; |
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245 | | - |
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246 | | - /* |
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247 | | - * In order to force the compiler to emit data independent Sbox lookups |
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248 | | - * at the start of each block, xor the first round key with values at |
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249 | | - * fixed indexes in the Sbox. This will need to be repeated each time |
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250 | | - * the key is used, which will pull the entire Sbox into the D-cache |
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251 | | - * before any data dependent Sbox lookups are performed. |
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252 | | - */ |
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253 | | - ctx->key_enc[0] ^= __aesti_sbox[ 0] ^ __aesti_sbox[128]; |
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254 | | - ctx->key_enc[1] ^= __aesti_sbox[32] ^ __aesti_sbox[160]; |
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255 | | - ctx->key_enc[2] ^= __aesti_sbox[64] ^ __aesti_sbox[192]; |
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256 | | - ctx->key_enc[3] ^= __aesti_sbox[96] ^ __aesti_sbox[224]; |
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257 | | - |
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258 | | - ctx->key_dec[0] ^= __aesti_inv_sbox[ 0] ^ __aesti_inv_sbox[128]; |
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259 | | - ctx->key_dec[1] ^= __aesti_inv_sbox[32] ^ __aesti_inv_sbox[160]; |
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260 | | - ctx->key_dec[2] ^= __aesti_inv_sbox[64] ^ __aesti_inv_sbox[192]; |
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261 | | - ctx->key_dec[3] ^= __aesti_inv_sbox[96] ^ __aesti_inv_sbox[224]; |
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262 | | - |
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263 | | - return 0; |
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| 17 | + return aes_expandkey(ctx, in_key, key_len); |
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264 | 18 | } |
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265 | 19 | |
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266 | 20 | static void aesti_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) |
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267 | 21 | { |
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268 | 22 | const struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm); |
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269 | | - const u32 *rkp = ctx->key_enc + 4; |
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270 | | - int rounds = 6 + ctx->key_length / 4; |
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271 | | - u32 st0[4], st1[4]; |
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272 | 23 | unsigned long flags; |
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273 | | - int round; |
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274 | | - |
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275 | | - st0[0] = ctx->key_enc[0] ^ get_unaligned_le32(in); |
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276 | | - st0[1] = ctx->key_enc[1] ^ get_unaligned_le32(in + 4); |
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277 | | - st0[2] = ctx->key_enc[2] ^ get_unaligned_le32(in + 8); |
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278 | | - st0[3] = ctx->key_enc[3] ^ get_unaligned_le32(in + 12); |
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279 | 24 | |
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280 | 25 | /* |
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281 | 26 | * Temporarily disable interrupts to avoid races where cachelines are |
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.. | .. |
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283 | 28 | */ |
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284 | 29 | local_irq_save(flags); |
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285 | 30 | |
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286 | | - st0[0] ^= __aesti_sbox[ 0] ^ __aesti_sbox[128]; |
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287 | | - st0[1] ^= __aesti_sbox[32] ^ __aesti_sbox[160]; |
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288 | | - st0[2] ^= __aesti_sbox[64] ^ __aesti_sbox[192]; |
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289 | | - st0[3] ^= __aesti_sbox[96] ^ __aesti_sbox[224]; |
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290 | | - |
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291 | | - for (round = 0;; round += 2, rkp += 8) { |
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292 | | - st1[0] = mix_columns(subshift(st0, 0)) ^ rkp[0]; |
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293 | | - st1[1] = mix_columns(subshift(st0, 1)) ^ rkp[1]; |
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294 | | - st1[2] = mix_columns(subshift(st0, 2)) ^ rkp[2]; |
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295 | | - st1[3] = mix_columns(subshift(st0, 3)) ^ rkp[3]; |
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296 | | - |
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297 | | - if (round == rounds - 2) |
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298 | | - break; |
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299 | | - |
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300 | | - st0[0] = mix_columns(subshift(st1, 0)) ^ rkp[4]; |
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301 | | - st0[1] = mix_columns(subshift(st1, 1)) ^ rkp[5]; |
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302 | | - st0[2] = mix_columns(subshift(st1, 2)) ^ rkp[6]; |
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303 | | - st0[3] = mix_columns(subshift(st1, 3)) ^ rkp[7]; |
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304 | | - } |
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305 | | - |
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306 | | - put_unaligned_le32(subshift(st1, 0) ^ rkp[4], out); |
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307 | | - put_unaligned_le32(subshift(st1, 1) ^ rkp[5], out + 4); |
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308 | | - put_unaligned_le32(subshift(st1, 2) ^ rkp[6], out + 8); |
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309 | | - put_unaligned_le32(subshift(st1, 3) ^ rkp[7], out + 12); |
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| 31 | + aes_encrypt(ctx, out, in); |
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310 | 32 | |
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311 | 33 | local_irq_restore(flags); |
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312 | 34 | } |
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.. | .. |
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314 | 36 | static void aesti_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) |
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315 | 37 | { |
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316 | 38 | const struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm); |
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317 | | - const u32 *rkp = ctx->key_dec + 4; |
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318 | | - int rounds = 6 + ctx->key_length / 4; |
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319 | | - u32 st0[4], st1[4]; |
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320 | 39 | unsigned long flags; |
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321 | | - int round; |
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322 | | - |
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323 | | - st0[0] = ctx->key_dec[0] ^ get_unaligned_le32(in); |
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324 | | - st0[1] = ctx->key_dec[1] ^ get_unaligned_le32(in + 4); |
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325 | | - st0[2] = ctx->key_dec[2] ^ get_unaligned_le32(in + 8); |
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326 | | - st0[3] = ctx->key_dec[3] ^ get_unaligned_le32(in + 12); |
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327 | 40 | |
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328 | 41 | /* |
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329 | 42 | * Temporarily disable interrupts to avoid races where cachelines are |
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.. | .. |
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331 | 44 | */ |
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332 | 45 | local_irq_save(flags); |
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333 | 46 | |
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334 | | - st0[0] ^= __aesti_inv_sbox[ 0] ^ __aesti_inv_sbox[128]; |
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335 | | - st0[1] ^= __aesti_inv_sbox[32] ^ __aesti_inv_sbox[160]; |
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336 | | - st0[2] ^= __aesti_inv_sbox[64] ^ __aesti_inv_sbox[192]; |
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337 | | - st0[3] ^= __aesti_inv_sbox[96] ^ __aesti_inv_sbox[224]; |
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338 | | - |
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339 | | - for (round = 0;; round += 2, rkp += 8) { |
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340 | | - st1[0] = inv_mix_columns(inv_subshift(st0, 0)) ^ rkp[0]; |
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341 | | - st1[1] = inv_mix_columns(inv_subshift(st0, 1)) ^ rkp[1]; |
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342 | | - st1[2] = inv_mix_columns(inv_subshift(st0, 2)) ^ rkp[2]; |
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343 | | - st1[3] = inv_mix_columns(inv_subshift(st0, 3)) ^ rkp[3]; |
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344 | | - |
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345 | | - if (round == rounds - 2) |
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346 | | - break; |
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347 | | - |
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348 | | - st0[0] = inv_mix_columns(inv_subshift(st1, 0)) ^ rkp[4]; |
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349 | | - st0[1] = inv_mix_columns(inv_subshift(st1, 1)) ^ rkp[5]; |
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350 | | - st0[2] = inv_mix_columns(inv_subshift(st1, 2)) ^ rkp[6]; |
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351 | | - st0[3] = inv_mix_columns(inv_subshift(st1, 3)) ^ rkp[7]; |
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352 | | - } |
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353 | | - |
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354 | | - put_unaligned_le32(inv_subshift(st1, 0) ^ rkp[4], out); |
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355 | | - put_unaligned_le32(inv_subshift(st1, 1) ^ rkp[5], out + 4); |
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356 | | - put_unaligned_le32(inv_subshift(st1, 2) ^ rkp[6], out + 8); |
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357 | | - put_unaligned_le32(inv_subshift(st1, 3) ^ rkp[7], out + 12); |
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| 47 | + aes_decrypt(ctx, out, in); |
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358 | 48 | |
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359 | 49 | local_irq_restore(flags); |
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360 | 50 | } |
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