mirror of
https://github.com/lwvmobile/dsd-fme.git
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923 lines
28 KiB
C
923 lines
28 KiB
C
/*-------------------------------------------------------------------------------
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* aes.c Tinier AES
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* Easy To Use (and configurable) AES Output and Utility Bit/Byte Functions
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*
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* Modified Tiny AES code for more variable nk/nr/nb values, all in one file
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* https://github.com/kokke/tiny-AES-c
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*-----------------------------------------------------------------------------*/
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/*
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This is free and unencumbered software released into the public domain.
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Anyone is free to copy, modify, publish, use, compile, sell, or
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distribute this software, either in source code form or as a compiled
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binary, for any purpose, commercial or non-commercial, and by any
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means.
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In jurisdictions that recognize copyright laws, the author or authors
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of this software dedicate any and all copyright interest in the
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software to the public domain. We make this dedication for the benefit
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of the public at large and to the detriment of our heirs and
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successors. We intend this dedication to be an overt act of
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relinquishment in perpetuity of all present and future rights to this
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software under copyright law.
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
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IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
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OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
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ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
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OTHER DEALINGS IN THE SOFTWARE.
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For more information, please refer to <http://unlicense.org/>
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*/
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#include <string.h>
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#include <stdint.h>
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#include <stddef.h>
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#include "dsd.h"
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#define AES_BLOCKLEN 16
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unsigned Nb = 4;
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unsigned Nk = 8;
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unsigned Nr = 14;
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struct AES_ctx
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{
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uint8_t RoundKey[240];
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uint8_t Iv[16];
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};
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//internal function prototypes
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void AES_init_ctx(struct AES_ctx* ctx, const uint8_t* key);
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void AES_init_ctx_iv(struct AES_ctx* ctx, const uint8_t* key, const uint8_t* iv);
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void AES_ctx_set_iv(struct AES_ctx* ctx, const uint8_t* iv);
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void AES_ECB_encrypt(const struct AES_ctx* ctx, uint8_t* buf);
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void AES_ECB_decrypt(const struct AES_ctx* ctx, uint8_t* buf);
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void AES_CBC_encrypt_buffer(struct AES_ctx* ctx, uint8_t* buf, size_t length);
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void AES_CBC_decrypt_buffer(struct AES_ctx* ctx, uint8_t* buf, size_t length);
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void AES_CTR_xcrypt_buffer(struct AES_ctx* ctx, uint8_t* buf, size_t length);
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typedef uint8_t state_t[4][4];
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static const uint8_t sbox[256] = {
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//0 1 2 3 4 5 6 7 8 9 A B C D E F
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0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, 0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76,
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0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0, 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0,
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0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc, 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15,
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0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75,
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0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84,
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0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b, 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf,
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0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8,
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0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2,
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0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17, 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73,
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0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, 0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb,
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0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c, 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79,
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0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9, 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08,
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0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6, 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a,
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0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e, 0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e,
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0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94, 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf,
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0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, 0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16 };
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static const uint8_t rsbox[256] = {
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0x52, 0x09, 0x6a, 0xd5, 0x30, 0x36, 0xa5, 0x38, 0xbf, 0x40, 0xa3, 0x9e, 0x81, 0xf3, 0xd7, 0xfb,
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0x7c, 0xe3, 0x39, 0x82, 0x9b, 0x2f, 0xff, 0x87, 0x34, 0x8e, 0x43, 0x44, 0xc4, 0xde, 0xe9, 0xcb,
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0x54, 0x7b, 0x94, 0x32, 0xa6, 0xc2, 0x23, 0x3d, 0xee, 0x4c, 0x95, 0x0b, 0x42, 0xfa, 0xc3, 0x4e,
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0x08, 0x2e, 0xa1, 0x66, 0x28, 0xd9, 0x24, 0xb2, 0x76, 0x5b, 0xa2, 0x49, 0x6d, 0x8b, 0xd1, 0x25,
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0x72, 0xf8, 0xf6, 0x64, 0x86, 0x68, 0x98, 0x16, 0xd4, 0xa4, 0x5c, 0xcc, 0x5d, 0x65, 0xb6, 0x92,
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0x6c, 0x70, 0x48, 0x50, 0xfd, 0xed, 0xb9, 0xda, 0x5e, 0x15, 0x46, 0x57, 0xa7, 0x8d, 0x9d, 0x84,
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0x90, 0xd8, 0xab, 0x00, 0x8c, 0xbc, 0xd3, 0x0a, 0xf7, 0xe4, 0x58, 0x05, 0xb8, 0xb3, 0x45, 0x06,
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0xd0, 0x2c, 0x1e, 0x8f, 0xca, 0x3f, 0x0f, 0x02, 0xc1, 0xaf, 0xbd, 0x03, 0x01, 0x13, 0x8a, 0x6b,
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0x3a, 0x91, 0x11, 0x41, 0x4f, 0x67, 0xdc, 0xea, 0x97, 0xf2, 0xcf, 0xce, 0xf0, 0xb4, 0xe6, 0x73,
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0x96, 0xac, 0x74, 0x22, 0xe7, 0xad, 0x35, 0x85, 0xe2, 0xf9, 0x37, 0xe8, 0x1c, 0x75, 0xdf, 0x6e,
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0x47, 0xf1, 0x1a, 0x71, 0x1d, 0x29, 0xc5, 0x89, 0x6f, 0xb7, 0x62, 0x0e, 0xaa, 0x18, 0xbe, 0x1b,
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0xfc, 0x56, 0x3e, 0x4b, 0xc6, 0xd2, 0x79, 0x20, 0x9a, 0xdb, 0xc0, 0xfe, 0x78, 0xcd, 0x5a, 0xf4,
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0x1f, 0xdd, 0xa8, 0x33, 0x88, 0x07, 0xc7, 0x31, 0xb1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xec, 0x5f,
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0x60, 0x51, 0x7f, 0xa9, 0x19, 0xb5, 0x4a, 0x0d, 0x2d, 0xe5, 0x7a, 0x9f, 0x93, 0xc9, 0x9c, 0xef,
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0xa0, 0xe0, 0x3b, 0x4d, 0xae, 0x2a, 0xf5, 0xb0, 0xc8, 0xeb, 0xbb, 0x3c, 0x83, 0x53, 0x99, 0x61,
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0x17, 0x2b, 0x04, 0x7e, 0xba, 0x77, 0xd6, 0x26, 0xe1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0c, 0x7d };
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static const uint8_t Rcon[11] = {
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0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36 };
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#define getSBoxValue(num) (sbox[(num)])
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static void KeyExpansion(uint8_t* RoundKey, const uint8_t* Key)
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{
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unsigned i, j, k;
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uint8_t tempa[4]; // Used for the column/row operations
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// The first round key is the key itself.
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for (i = 0; i < Nk; ++i)
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{
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RoundKey[(i * 4) + 0] = Key[(i * 4) + 0];
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RoundKey[(i * 4) + 1] = Key[(i * 4) + 1];
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RoundKey[(i * 4) + 2] = Key[(i * 4) + 2];
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RoundKey[(i * 4) + 3] = Key[(i * 4) + 3];
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}
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// All other round keys are found from the previous round keys.
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for (i = Nk; i < Nb * (Nr + 1); ++i)
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{
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{
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k = (i - 1) * 4;
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tempa[0]=RoundKey[k + 0];
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tempa[1]=RoundKey[k + 1];
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tempa[2]=RoundKey[k + 2];
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tempa[3]=RoundKey[k + 3];
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}
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if (i % Nk == 0)
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{
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// This function shifts the 4 bytes in a word to the left once.
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// [a0,a1,a2,a3] becomes [a1,a2,a3,a0]
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// Function RotWord()
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{
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const uint8_t u8tmp = tempa[0];
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tempa[0] = tempa[1];
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tempa[1] = tempa[2];
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tempa[2] = tempa[3];
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tempa[3] = u8tmp;
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}
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// SubWord() is a function that takes a four-byte input word and
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// applies the S-box to each of the four bytes to produce an output word.
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// Function Subword()
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{
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tempa[0] = getSBoxValue(tempa[0]);
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tempa[1] = getSBoxValue(tempa[1]);
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tempa[2] = getSBoxValue(tempa[2]);
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tempa[3] = getSBoxValue(tempa[3]);
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}
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tempa[0] = tempa[0] ^ Rcon[i/Nk];
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}
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if (Nk == 8) //only run if using AES256 (Nk == 8)
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{
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if (i % Nk == 4)
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{
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// Function Subword()
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{
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tempa[0] = getSBoxValue(tempa[0]);
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tempa[1] = getSBoxValue(tempa[1]);
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tempa[2] = getSBoxValue(tempa[2]);
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tempa[3] = getSBoxValue(tempa[3]);
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}
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}
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}
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j = i * 4; k=(i - Nk) * 4;
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RoundKey[j + 0] = RoundKey[k + 0] ^ tempa[0];
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RoundKey[j + 1] = RoundKey[k + 1] ^ tempa[1];
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RoundKey[j + 2] = RoundKey[k + 2] ^ tempa[2];
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RoundKey[j + 3] = RoundKey[k + 3] ^ tempa[3];
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}
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}
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//input bit array, return output as up to a 64-bit value
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uint64_t convert_bits_into_output_ta(uint8_t * input, int len)
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{
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int i;
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uint64_t output = 0;
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for(i = 0; i < len; i++)
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{
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output <<= 1;
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output |= (uint64_t)(input[i] & 1);
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}
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return output;
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}
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//take x amount of bits and pack into len amount of bytes (symmetrical)
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void pack_bit_array_into_byte_array_ta (uint8_t * input, uint8_t * output, int len)
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{
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int i;
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for (i = 0; i < len; i++)
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output[i] = (uint8_t)convert_bits_into_output_ta(&input[i*8], 8);
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}
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//take len amount of bytes and unpack back into a bit array
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void unpack_byte_array_into_bit_array_ta (uint8_t * input, uint8_t * output, int len)
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{
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int i = 0, k = 0;
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for (i = 0; i < len; i++)
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{
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output[k++] = (input[i] >> 7) & 1;
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output[k++] = (input[i] >> 6) & 1;
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output[k++] = (input[i] >> 5) & 1;
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output[k++] = (input[i] >> 4) & 1;
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output[k++] = (input[i] >> 3) & 1;
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output[k++] = (input[i] >> 2) & 1;
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output[k++] = (input[i] >> 1) & 1;
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output[k++] = (input[i] >> 0) & 1;
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}
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}
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void AES_init_ctx(struct AES_ctx* ctx, const uint8_t* key)
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{
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KeyExpansion(ctx->RoundKey, key);
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}
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void AES_init_ctx_iv(struct AES_ctx* ctx, const uint8_t* key, const uint8_t* iv)
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{
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KeyExpansion(ctx->RoundKey, key);
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memcpy (ctx->Iv, iv, AES_BLOCKLEN);
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}
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void AES_ctx_set_iv(struct AES_ctx* ctx, const uint8_t* iv)
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{
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memcpy (ctx->Iv, iv, AES_BLOCKLEN);
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}
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static void AddRoundKey(uint8_t round, state_t* state, const uint8_t* RoundKey)
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{
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uint8_t i,j;
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for (i = 0; i < 4; ++i)
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{
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for (j = 0; j < 4; ++j)
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{
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(*state)[i][j] ^= RoundKey[(round * Nb * 4) + (i * Nb) + j];
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}
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}
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}
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static void SubBytes(state_t* state)
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{
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uint8_t i, j;
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for (i = 0; i < 4; ++i)
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{
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for (j = 0; j < 4; ++j)
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{
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(*state)[j][i] = getSBoxValue((*state)[j][i]);
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}
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}
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}
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static void ShiftRows(state_t* state)
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{
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uint8_t temp;
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// Rotate first row 1 columns to left
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temp = (*state)[0][1];
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(*state)[0][1] = (*state)[1][1];
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(*state)[1][1] = (*state)[2][1];
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(*state)[2][1] = (*state)[3][1];
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(*state)[3][1] = temp;
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// Rotate second row 2 columns to left
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temp = (*state)[0][2];
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(*state)[0][2] = (*state)[2][2];
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(*state)[2][2] = temp;
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temp = (*state)[1][2];
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(*state)[1][2] = (*state)[3][2];
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(*state)[3][2] = temp;
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// Rotate third row 3 columns to left
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temp = (*state)[0][3];
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(*state)[0][3] = (*state)[3][3];
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(*state)[3][3] = (*state)[2][3];
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(*state)[2][3] = (*state)[1][3];
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(*state)[1][3] = temp;
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}
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static uint8_t xtime(uint8_t x)
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{
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return ((x<<1) ^ (((x>>7) & 1) * 0x1b));
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}
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static void MixColumns(state_t* state)
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{
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uint8_t i;
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uint8_t Tmp, Tm, t;
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for (i = 0; i < 4; ++i)
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{
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t = (*state)[i][0];
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Tmp = (*state)[i][0] ^ (*state)[i][1] ^ (*state)[i][2] ^ (*state)[i][3] ;
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Tm = (*state)[i][0] ^ (*state)[i][1] ; Tm = xtime(Tm); (*state)[i][0] ^= Tm ^ Tmp ;
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Tm = (*state)[i][1] ^ (*state)[i][2] ; Tm = xtime(Tm); (*state)[i][1] ^= Tm ^ Tmp ;
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Tm = (*state)[i][2] ^ (*state)[i][3] ; Tm = xtime(Tm); (*state)[i][2] ^= Tm ^ Tmp ;
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Tm = (*state)[i][3] ^ t ; Tm = xtime(Tm); (*state)[i][3] ^= Tm ^ Tmp ;
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}
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}
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#define Multiply(x, y) \
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( ((y & 1) * x) ^ \
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((y>>1 & 1) * xtime(x)) ^ \
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((y>>2 & 1) * xtime(xtime(x))) ^ \
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((y>>3 & 1) * xtime(xtime(xtime(x)))) ^ \
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((y>>4 & 1) * xtime(xtime(xtime(xtime(x)))))) \
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#define getSBoxInvert(num) (rsbox[(num)])
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static void InvMixColumns(state_t* state)
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{
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int i;
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uint8_t a, b, c, d;
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for (i = 0; i < 4; ++i)
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{
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a = (*state)[i][0];
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b = (*state)[i][1];
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c = (*state)[i][2];
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d = (*state)[i][3];
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(*state)[i][0] = Multiply(a, 0x0e) ^ Multiply(b, 0x0b) ^ Multiply(c, 0x0d) ^ Multiply(d, 0x09);
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(*state)[i][1] = Multiply(a, 0x09) ^ Multiply(b, 0x0e) ^ Multiply(c, 0x0b) ^ Multiply(d, 0x0d);
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(*state)[i][2] = Multiply(a, 0x0d) ^ Multiply(b, 0x09) ^ Multiply(c, 0x0e) ^ Multiply(d, 0x0b);
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(*state)[i][3] = Multiply(a, 0x0b) ^ Multiply(b, 0x0d) ^ Multiply(c, 0x09) ^ Multiply(d, 0x0e);
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}
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}
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static void InvSubBytes(state_t* state)
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{
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uint8_t i, j;
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for (i = 0; i < 4; ++i)
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{
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for (j = 0; j < 4; ++j)
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{
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(*state)[j][i] = getSBoxInvert((*state)[j][i]);
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}
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}
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}
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static void InvShiftRows(state_t* state)
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{
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uint8_t temp;
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// Rotate first row 1 columns to right
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temp = (*state)[3][1];
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(*state)[3][1] = (*state)[2][1];
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(*state)[2][1] = (*state)[1][1];
|
|
(*state)[1][1] = (*state)[0][1];
|
|
(*state)[0][1] = temp;
|
|
|
|
// Rotate second row 2 columns to right
|
|
temp = (*state)[0][2];
|
|
(*state)[0][2] = (*state)[2][2];
|
|
(*state)[2][2] = temp;
|
|
|
|
temp = (*state)[1][2];
|
|
(*state)[1][2] = (*state)[3][2];
|
|
(*state)[3][2] = temp;
|
|
|
|
// Rotate third row 3 columns to right
|
|
temp = (*state)[0][3];
|
|
(*state)[0][3] = (*state)[1][3];
|
|
(*state)[1][3] = (*state)[2][3];
|
|
(*state)[2][3] = (*state)[3][3];
|
|
(*state)[3][3] = temp;
|
|
}
|
|
|
|
// Cipher is the main function that encrypts the PlainText,
|
|
// or produces a keystream, depending on application.
|
|
static void Cipher(state_t* state, const uint8_t* RoundKey)
|
|
{
|
|
uint8_t round = 0;
|
|
|
|
// Add the First round key to the state before starting the rounds.
|
|
AddRoundKey(0, state, RoundKey);
|
|
|
|
// There will be Nr rounds.
|
|
// The first Nr-1 rounds are identical.
|
|
// These Nr rounds are executed in the loop below.
|
|
// Last one without MixColumns()
|
|
for (round = 1; ; ++round)
|
|
{
|
|
SubBytes(state);
|
|
ShiftRows(state);
|
|
if (round == Nr) {
|
|
break;
|
|
}
|
|
MixColumns(state);
|
|
AddRoundKey(round, state, RoundKey);
|
|
}
|
|
// Add round key to last round
|
|
AddRoundKey(Nr, state, RoundKey);
|
|
}
|
|
|
|
static void InvCipher(state_t* state, const uint8_t* RoundKey)
|
|
{
|
|
uint8_t round = 0;
|
|
|
|
// Add the First round key to the state before starting the rounds.
|
|
AddRoundKey(Nr, state, RoundKey);
|
|
|
|
// There will be Nr rounds.
|
|
// The first Nr-1 rounds are identical.
|
|
// These Nr rounds are executed in the loop below.
|
|
// Last one without InvMixColumn()
|
|
for (round = (Nr - 1); ; --round)
|
|
{
|
|
InvShiftRows(state);
|
|
InvSubBytes(state);
|
|
AddRoundKey(round, state, RoundKey);
|
|
if (round == 0) {
|
|
break;
|
|
}
|
|
InvMixColumns(state);
|
|
}
|
|
|
|
}
|
|
|
|
void AES_ECB_encrypt(const struct AES_ctx* ctx, uint8_t* buf)
|
|
{
|
|
// The next function call encrypts the PlainText with the Key using AES algorithm.
|
|
Cipher((state_t*)buf, ctx->RoundKey);
|
|
}
|
|
|
|
void AES_ECB_decrypt(const struct AES_ctx* ctx, uint8_t* buf)
|
|
{
|
|
// The next function call decrypts the PlainText with the Key using AES algorithm.
|
|
InvCipher((state_t*)buf, ctx->RoundKey);
|
|
}
|
|
|
|
static void XorWithIv(uint8_t* buf, const uint8_t* Iv)
|
|
{
|
|
uint8_t i;
|
|
for (i = 0; i < AES_BLOCKLEN; ++i)
|
|
{
|
|
buf[i] ^= Iv[i];
|
|
}
|
|
}
|
|
|
|
void AES_CBC_encrypt_buffer(struct AES_ctx *ctx, uint8_t* buf, size_t length)
|
|
{
|
|
size_t i;
|
|
uint8_t *Iv = ctx->Iv;
|
|
for (i = 0; i < length; i += AES_BLOCKLEN)
|
|
{
|
|
XorWithIv(buf, Iv);
|
|
Cipher((state_t*)buf, ctx->RoundKey);
|
|
Iv = buf;
|
|
buf += AES_BLOCKLEN;
|
|
}
|
|
/* store Iv in ctx for next call */
|
|
memcpy(ctx->Iv, Iv, AES_BLOCKLEN);
|
|
}
|
|
|
|
void AES_CBC_decrypt_buffer(struct AES_ctx* ctx, uint8_t* buf, size_t length)
|
|
{
|
|
size_t i;
|
|
uint8_t storeNextIv[AES_BLOCKLEN];
|
|
for (i = 0; i < length; i += AES_BLOCKLEN)
|
|
{
|
|
memcpy(storeNextIv, buf, AES_BLOCKLEN);
|
|
InvCipher((state_t*)buf, ctx->RoundKey);
|
|
XorWithIv(buf, ctx->Iv);
|
|
memcpy(ctx->Iv, storeNextIv, AES_BLOCKLEN);
|
|
buf += AES_BLOCKLEN;
|
|
}
|
|
|
|
}
|
|
|
|
/* Symmetrical operation: same function for encrypting as for decrypting. Note any IV/nonce should never be reused with the same key */
|
|
void AES_CTR_xcrypt_buffer(struct AES_ctx* ctx, uint8_t* buf, size_t length)
|
|
{
|
|
uint8_t buffer[AES_BLOCKLEN];
|
|
|
|
size_t i;
|
|
int bi;
|
|
for (i = 0, bi = AES_BLOCKLEN; i < length; ++i, ++bi)
|
|
{
|
|
if (bi == AES_BLOCKLEN) /* we need to regen xor compliment in buffer */
|
|
{
|
|
|
|
memcpy(buffer, ctx->Iv, AES_BLOCKLEN);
|
|
Cipher((state_t*)buffer,ctx->RoundKey);
|
|
|
|
/* Increment Iv and handle overflow */
|
|
for (bi = (AES_BLOCKLEN - 1); bi >= 0; --bi)
|
|
{
|
|
/* inc will overflow */
|
|
if (ctx->Iv[bi] == 255)
|
|
{
|
|
ctx->Iv[bi] = 0;
|
|
continue;
|
|
}
|
|
ctx->Iv[bi] += 1;
|
|
break;
|
|
}
|
|
bi = 0;
|
|
}
|
|
|
|
buf[i] = (buf[i] ^ buffer[bi]);
|
|
}
|
|
|
|
}
|
|
|
|
//byte-wise output of AES OFB Keystream
|
|
//input iv is a 16-byte uint8_t array of initialization vector
|
|
//input key is up to 32-byte uint8_t array of key value
|
|
//input type is the type/key len of AES required (0-128, 1-192, 2-256)
|
|
//input nblocks is the number of rounds of 16-byte keystream output blocks requried
|
|
//output is a uint8_t bytewise array, each round filled with 16-bytes from aes keystream output
|
|
void aes_ofb_keystream_output (uint8_t * iv, uint8_t * key, uint8_t * output, int type, int nblocks)
|
|
{
|
|
|
|
int i;
|
|
uint8_t input_register[16]; //OFB Input Register
|
|
memset (input_register, 0, sizeof(input_register));
|
|
|
|
//Set values specific to type (128/192/256)
|
|
if (type == 0) //128
|
|
{
|
|
Nb = 4;
|
|
Nk = 4;
|
|
Nr = 10;
|
|
}
|
|
else if (type == 1) //192
|
|
{
|
|
Nb = 4;
|
|
Nk = 6;
|
|
Nr = 12;
|
|
}
|
|
else //if (type == 2) //256
|
|
{
|
|
Nb = 4;
|
|
Nk = 8;
|
|
Nr = 14;
|
|
}
|
|
|
|
struct AES_ctx ctx;
|
|
|
|
//load first round of input_register with received IV (OFB First Input Register)
|
|
memcpy (input_register, iv, 16*sizeof(uint8_t) );
|
|
|
|
//initialize the key variable for the Cipher function
|
|
memset (ctx.RoundKey, 0, 240*sizeof(uint8_t));
|
|
KeyExpansion(ctx.RoundKey, key);
|
|
|
|
//execute the cipher function, and copy ciphered input_register to output for required number of rounds
|
|
for (i = 0; i < nblocks; i++)
|
|
{
|
|
Cipher((state_t*)input_register, ctx.RoundKey); //input_register is returned as output, and is put back in as object feedback
|
|
memcpy (output+(i*16), input_register, 16*sizeof(uint8_t) ); //copy ciphered input_register to output
|
|
}
|
|
|
|
}
|
|
|
|
//byte-wise AES CFB (Cipher Feedback) Payload operating in 128-bit block mode
|
|
//input in is a uint8_t bytewise array,is the input to be ciphered (encrypted or decrypted)
|
|
//input iv is a 16-byte uint8_t array of initialization vector
|
|
//input key is up to 32-byte uint8_t array of key value
|
|
//input type is the type/key len of AES required (0-128, 1-192, 2-256)
|
|
//input nblocks is the number of rounds of 16-byte payload blocks requried (last block will need padding if not flush)
|
|
//output out is a uint8_t bytewise array, each round filled with 16-bytes of cfb ciphered output (encrypted or decrypted)
|
|
//de is a bit-flag signalling to run Cipher (encrypt) on 1, or InvCipher (decrypt) on 0
|
|
void aes_cfb_bytewise_payload_crypt (uint8_t * iv, uint8_t * key, uint8_t * in, uint8_t * out, int type, int nblocks, int de)
|
|
{
|
|
|
|
int i, j;
|
|
uint8_t input_register[16]; //Input Register
|
|
memset (input_register, 0, sizeof(input_register));
|
|
|
|
//Set values specific to type (128/192/256)
|
|
if (type == 0) //128
|
|
{
|
|
Nb = 4;
|
|
Nk = 4;
|
|
Nr = 10;
|
|
}
|
|
else if (type == 1) //192
|
|
{
|
|
Nb = 4;
|
|
Nk = 6;
|
|
Nr = 12;
|
|
}
|
|
else //if (type == 2) //256
|
|
{
|
|
Nb = 4;
|
|
Nk = 8;
|
|
Nr = 14;
|
|
}
|
|
|
|
struct AES_ctx ctx;
|
|
|
|
//load first round of input_register with received IV (CFB First Input Register)
|
|
memcpy (input_register, iv, 16*sizeof(uint8_t) );
|
|
|
|
//initialize the key variable for the Cipher function
|
|
memset (ctx.RoundKey, 0, 240*sizeof(uint8_t));
|
|
KeyExpansion(ctx.RoundKey, key);
|
|
|
|
//execute the cipher function, and copy ciphered input_register to output for required number of rounds
|
|
for (i = 0; i < nblocks; i++)
|
|
{
|
|
|
|
//the cipher is always run in the foward, or encryption mode
|
|
Cipher((state_t*)input_register, ctx.RoundKey);
|
|
|
|
//xor the current input 'in' to the current state of the input_register for cipher feedback
|
|
for (j = 0; j < 16; j++)
|
|
input_register[j] ^= in[j+(i*16)];
|
|
|
|
//copy ciphered/xor'd input_register to output 'out'
|
|
memcpy (out+(i*16), input_register, 16*sizeof(uint8_t) );
|
|
|
|
//if running in decryption mode, we feed in the next round of input
|
|
if (!de)
|
|
memcpy(input_register, in+(i*16), 16*sizeof(uint8_t));
|
|
|
|
}
|
|
|
|
}
|
|
|
|
//byte-wise AES CBC (Cipher Block Chaining) //Yeah, I know this already exists, but wanted a custom convenience wrapper version
|
|
//input in is a uint8_t bytewise array,is the input to be ciphered (encrypted or decrypted)
|
|
//input iv is a 16-byte uint8_t array of initialization vector
|
|
//input key is up to 32-byte uint8_t array of key value
|
|
//input type is the type/key len of AES required (0-128, 1-192, 2-256)
|
|
//input nblocks is the number of rounds of 16-byte payload blocks requried (last block will need padding if not flush)
|
|
//output out is a uint8_t bytewise array, each round filled with 16-bytes of cfb ciphered output (encrypted or decrypted)
|
|
//de is a bit-flag signalling to run Cipher (encrypt) on 1, or InvCipher (decrypt) on 0
|
|
void aes_cbc_bytewise_payload_crypt (uint8_t * iv, uint8_t * key, uint8_t * in, uint8_t * out, int type, int nblocks, int de)
|
|
{
|
|
|
|
int i, j;
|
|
uint8_t input_register[16]; //Input Register
|
|
memset (input_register, 0, sizeof(input_register));
|
|
|
|
//Set values specific to type (128/192/256)
|
|
if (type == 0) //128
|
|
{
|
|
Nb = 4;
|
|
Nk = 4;
|
|
Nr = 10;
|
|
}
|
|
else if (type == 1) //192
|
|
{
|
|
Nb = 4;
|
|
Nk = 6;
|
|
Nr = 12;
|
|
}
|
|
else //if (type == 2) //256
|
|
{
|
|
Nb = 4;
|
|
Nk = 8;
|
|
Nr = 14;
|
|
}
|
|
|
|
struct AES_ctx ctx;
|
|
|
|
//load first round of input_register accordingly
|
|
if (de)
|
|
memcpy (input_register, iv, 16*sizeof(uint8_t) );
|
|
else memcpy (input_register, in, 16*sizeof(uint8_t) );
|
|
|
|
//initialize the key variable for the Cipher function
|
|
memset (ctx.RoundKey, 0, 240*sizeof(uint8_t));
|
|
KeyExpansion(ctx.RoundKey, key);
|
|
|
|
//
|
|
for (i = 0; i < nblocks; i++)
|
|
{
|
|
|
|
//run encryption or decryption depending on de value
|
|
if (de) //encrypt
|
|
{
|
|
|
|
//xor the current input 'in' pt to the current state of the input_register for cbc feedback
|
|
for (j = 0; j < 16; j++)
|
|
input_register[j] ^= in[j+(i*16)];
|
|
|
|
Cipher((state_t*)input_register, ctx.RoundKey);
|
|
|
|
//copy ciphered input_register to output 'out'
|
|
memcpy (out+(i*16), input_register, 16*sizeof(uint8_t) );
|
|
|
|
}
|
|
|
|
else //decrypt
|
|
{
|
|
|
|
InvCipher((state_t*)input_register, ctx.RoundKey);
|
|
|
|
//copy ciphered input_register to output 'out'
|
|
memcpy (out+(i*16), input_register, 16*sizeof(uint8_t) );
|
|
|
|
//xor the current output by IV, or by last received CT
|
|
if (i == 0)
|
|
{
|
|
for (j = 0; j < 16; j++)
|
|
out[j] ^= iv[j];
|
|
}
|
|
else
|
|
{
|
|
for (j = 0; j < 16; j++)
|
|
out[j+(i*16)] ^= in[j+((i-1)*16)];
|
|
}
|
|
|
|
//copy in next segment for input_register (if not last)
|
|
if (i < nblocks)
|
|
memcpy(input_register, in+((i+1)*16), 16*sizeof(uint8_t) );
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
//byte-wise AES CBC_MAC (Cipher Block Chaining Message Authentication) //This is slightly different than above, no IV is present,
|
|
//but if iv is desireable, it will need to be pre-XOR'd with the first plaintext input block by the calling function
|
|
//input in is a uint8_t bytewise array, is the input to be ciphered.
|
|
//input key is up to 32-byte uint8_t array of key value
|
|
//input type is the type/key len of AES required (0-128, 1-192, 2-256)
|
|
//input nblocks is the number of rounds of 16-byte payload blocks requried (last block will need padding if not flush)
|
|
//output out is a uint8_t bytewise array, with only the final round output as the MAC octets
|
|
//NOTE: When doing a cbc_mac, you should only run it in the forward (encryption) mode to get the mac bytes
|
|
void aes_cbc_mac_generator (uint8_t * key, uint8_t * in, uint8_t * out, int type, int nblocks)
|
|
{
|
|
|
|
int i, j;
|
|
uint8_t input_register[16]; //Input Register
|
|
memset (input_register, 0, sizeof(input_register));
|
|
|
|
//Set values specific to type (128/192/256)
|
|
if (type == 0) //128
|
|
{
|
|
Nb = 4;
|
|
Nk = 4;
|
|
Nr = 10;
|
|
}
|
|
else if (type == 1) //192
|
|
{
|
|
Nb = 4;
|
|
Nk = 6;
|
|
Nr = 12;
|
|
}
|
|
else //if (type == 2) //256
|
|
{
|
|
Nb = 4;
|
|
Nk = 8;
|
|
Nr = 14;
|
|
}
|
|
|
|
struct AES_ctx ctx;
|
|
|
|
//initialize the key variable for the Cipher function
|
|
memset (ctx.RoundKey, 0, 240*sizeof(uint8_t));
|
|
KeyExpansion(ctx.RoundKey, key);
|
|
|
|
//
|
|
for (i = 0; i < nblocks; i++)
|
|
{
|
|
|
|
//xor the current input 'in' pt to the current state of the input_register for cbc feedback
|
|
//if this is the first iteration, this will load the first round plain text instead
|
|
for (j = 0; j < 16; j++)
|
|
input_register[j] ^= in[j+((i+0)*16)];
|
|
|
|
Cipher((state_t*)input_register, ctx.RoundKey);
|
|
|
|
//debug, load out all intermediate output register values
|
|
// memcpy (out+(i*16), input_register, 16*sizeof(uint8_t) );
|
|
|
|
}
|
|
|
|
//copy final ciphered input_register to output 'out', user will determine how many bytes of output they want for MAC
|
|
memcpy (out, input_register, 16*sizeof(uint8_t) );
|
|
|
|
}
|
|
|
|
//byte-wise output of AES ECB Ciphering/Deciphering
|
|
//input is uint8_t byte-wise (16-bytes) data to be ciphered or deciphered
|
|
//input key is up to 32-byte uint8_t array of key value
|
|
//input type is the type/len of AES required (0-128, 1-192, 2-256)
|
|
//output is a uint8_t bytewise array of ciphered or deciphered input
|
|
//de is a bit-flag signalling to run Cipher (encrypt) on 1, or InvCipher (decrypt) on 0
|
|
void aes_ecb_bytewise_payload_crypt (uint8_t * input, uint8_t * key, uint8_t * output, int type, int de)
|
|
{
|
|
|
|
uint8_t input_register[16]; //ECB Input Register
|
|
memset (input_register, 0, sizeof(input_register));
|
|
|
|
//Set values specific to type (128/192/256)
|
|
if (type == 0) //128
|
|
{
|
|
Nb = 4;
|
|
Nk = 4;
|
|
Nr = 10;
|
|
}
|
|
else if (type == 1) //192
|
|
{
|
|
Nb = 4;
|
|
Nk = 6;
|
|
Nr = 12;
|
|
}
|
|
else //if (type == 2) //256
|
|
{
|
|
Nb = 4;
|
|
Nk = 8;
|
|
Nr = 14;
|
|
}
|
|
|
|
struct AES_ctx ctx;
|
|
|
|
//load input_register with received input (ECB Payload)
|
|
memcpy (input_register, input, 16*sizeof(uint8_t) );
|
|
|
|
//initialize the key variable for the Cipher function
|
|
memset (ctx.RoundKey, 0, 240*sizeof(uint8_t));
|
|
KeyExpansion(ctx.RoundKey, key);
|
|
|
|
//run encryption or decryption depending on de value
|
|
if (de) //encrypt
|
|
Cipher((state_t*)input_register, ctx.RoundKey);
|
|
else //decrypt
|
|
InvCipher((state_t*)input_register, ctx.RoundKey);
|
|
|
|
//copy ciphered/deciphered input_register to output
|
|
memcpy (output, input_register, 16*sizeof(uint8_t) );
|
|
|
|
}
|
|
|
|
//symmetrical ctr mode payload encryption and decryption
|
|
void aes_ctr_bitwise_payload_crypt (uint8_t * iv, uint8_t * key, uint8_t * payload, int type)
|
|
{
|
|
|
|
//Set values specific to type (128/192/256)
|
|
if (type == 0) //128
|
|
{
|
|
Nb = 4;
|
|
Nk = 4;
|
|
Nr = 10;
|
|
}
|
|
else if (type == 1) //192
|
|
{
|
|
Nb = 4;
|
|
Nk = 6;
|
|
Nr = 12;
|
|
}
|
|
else //if (type == 2) //256
|
|
{
|
|
Nb = 4;
|
|
Nk = 8;
|
|
Nr = 14;
|
|
}
|
|
|
|
struct AES_ctx ctx;
|
|
|
|
//init and set the iv and key variables
|
|
memset (ctx.RoundKey, 0, 240*sizeof(uint8_t));
|
|
memset (ctx.Iv, 0, 16*sizeof(uint8_t));
|
|
|
|
KeyExpansion(ctx.RoundKey, key);
|
|
memcpy (ctx.Iv, iv, AES_BLOCKLEN);
|
|
|
|
//pack input bit-wise payload to byte array
|
|
uint8_t payload_bytes[16];
|
|
memset (payload_bytes, 0, sizeof(payload_bytes));
|
|
pack_bit_array_into_byte_array_ta (payload, payload_bytes, 16);
|
|
|
|
//pass to internal CTR handler for payload
|
|
AES_CTR_xcrypt_buffer(&ctx, payload_bytes, 16);
|
|
|
|
//unpack output bytes back to bits
|
|
unpack_byte_array_into_bit_array_ta(payload_bytes, payload, 16);
|
|
|
|
}
|
|
|
|
//symmetrical ctr mode payload encryption and decryption
|
|
void aes_ctr_bytewise_payload_crypt (uint8_t * iv, uint8_t * key, uint8_t * payload, int type)
|
|
{
|
|
|
|
//Set values specific to type (128/192/256)
|
|
if (type == 0) //128
|
|
{
|
|
Nb = 4;
|
|
Nk = 4;
|
|
Nr = 10;
|
|
}
|
|
else if (type == 1) //192
|
|
{
|
|
Nb = 4;
|
|
Nk = 6;
|
|
Nr = 12;
|
|
}
|
|
else //if (type == 2) //256
|
|
{
|
|
Nb = 4;
|
|
Nk = 8;
|
|
Nr = 14;
|
|
}
|
|
|
|
struct AES_ctx ctx;
|
|
|
|
//init and set the iv and key variables
|
|
memset (ctx.RoundKey, 0, 240*sizeof(uint8_t));
|
|
memset (ctx.Iv, 0, 16*sizeof(uint8_t));
|
|
|
|
KeyExpansion(ctx.RoundKey, key);
|
|
memcpy (ctx.Iv, iv, AES_BLOCKLEN);
|
|
|
|
//pass to internal CTR handler for payload
|
|
AES_CTR_xcrypt_buffer(&ctx, payload, 16);
|
|
|
|
}
|
|
|