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492 lines
14 KiB
C
492 lines
14 KiB
C
// http://gladman.plushost.co.uk/oldsite/AES/index.php
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#include <stdint.h>
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#include "aes.h"
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#define BPOLY 0x1B
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#define DPOLY 0x8D
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const uint8_t sbox[256] = {
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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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};
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const uint8_t isbox[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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};
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// #define xtime(x) ( (x << 1) ^ (((x >> 7) & 1) * BPOLY) )
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// #define xtime(x) ( (x << 1) ^ ((x & 0x80) ? BPOLY : 0) )
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const uint8_t xtime[256] = {
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0x00, 0x02, 0x04, 0x06, 0x08, 0x0a, 0x0c, 0x0e, 0x10, 0x12, 0x14, 0x16, 0x18, 0x1a, 0x1c, 0x1e,
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0x20, 0x22, 0x24, 0x26, 0x28, 0x2a, 0x2c, 0x2e, 0x30, 0x32, 0x34, 0x36, 0x38, 0x3a, 0x3c, 0x3e,
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0x40, 0x42, 0x44, 0x46, 0x48, 0x4a, 0x4c, 0x4e, 0x50, 0x52, 0x54, 0x56, 0x58, 0x5a, 0x5c, 0x5e,
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0x60, 0x62, 0x64, 0x66, 0x68, 0x6a, 0x6c, 0x6e, 0x70, 0x72, 0x74, 0x76, 0x78, 0x7a, 0x7c, 0x7e,
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0x80, 0x82, 0x84, 0x86, 0x88, 0x8a, 0x8c, 0x8e, 0x90, 0x92, 0x94, 0x96, 0x98, 0x9a, 0x9c, 0x9e,
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0xa0, 0xa2, 0xa4, 0xa6, 0xa8, 0xaa, 0xac, 0xae, 0xb0, 0xb2, 0xb4, 0xb6, 0xb8, 0xba, 0xbc, 0xbe,
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0xc0, 0xc2, 0xc4, 0xc6, 0xc8, 0xca, 0xcc, 0xce, 0xd0, 0xd2, 0xd4, 0xd6, 0xd8, 0xda, 0xdc, 0xde,
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0xe0, 0xe2, 0xe4, 0xe6, 0xe8, 0xea, 0xec, 0xee, 0xf0, 0xf2, 0xf4, 0xf6, 0xf8, 0xfa, 0xfc, 0xfe,
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0x1b, 0x19, 0x1f, 0x1d, 0x13, 0x11, 0x17, 0x15, 0x0b, 0x09, 0x0f, 0x0d, 0x03, 0x01, 0x07, 0x05,
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0x3b, 0x39, 0x3f, 0x3d, 0x33, 0x31, 0x37, 0x35, 0x2b, 0x29, 0x2f, 0x2d, 0x23, 0x21, 0x27, 0x25,
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0x5b, 0x59, 0x5f, 0x5d, 0x53, 0x51, 0x57, 0x55, 0x4b, 0x49, 0x4f, 0x4d, 0x43, 0x41, 0x47, 0x45,
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0x7b, 0x79, 0x7f, 0x7d, 0x73, 0x71, 0x77, 0x75, 0x6b, 0x69, 0x6f, 0x6d, 0x63, 0x61, 0x67, 0x65,
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0x9b, 0x99, 0x9f, 0x9d, 0x93, 0x91, 0x97, 0x95, 0x8b, 0x89, 0x8f, 0x8d, 0x83, 0x81, 0x87, 0x85,
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0xbb, 0xb9, 0xbf, 0xbd, 0xb3, 0xb1, 0xb7, 0xb5, 0xab, 0xa9, 0xaf, 0xad, 0xa3, 0xa1, 0xa7, 0xa5,
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0xdb, 0xd9, 0xdf, 0xdd, 0xd3, 0xd1, 0xd7, 0xd5, 0xcb, 0xc9, 0xcf, 0xcd, 0xc3, 0xc1, 0xc7, 0xc5,
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0xfb, 0xf9, 0xff, 0xfd, 0xf3, 0xf1, 0xf7, 0xf5, 0xeb, 0xe9, 0xef, 0xed, 0xe3, 0xe1, 0xe7, 0xe5
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};
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// ***********************************************************************************
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/*
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void createXTimeTable(void)
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{
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uint8_t i = 0;
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do {
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xtime[i] = (i << 1) ^ ((i & 0x80) ? BPOLY : 0);
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} while (++i != 0);
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}
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*/
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// ***********************************************************************************
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/*
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uint8_t powTable[256];
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uint8_t logTable[256];
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uint8_t sbox[256];
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uint8_t isbox[256];
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void createPowLogTables(void)
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{
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uint8_t i = 0;
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uint8_t t = 1;
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do {
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powTable[i] = t;
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logTable[t] = i;
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i++;
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t ^= (t << 1) ^ ((t & 0x80) ? BPOLY : 0);
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} while (t != 1);
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powTable[255] = powTable[0];
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}
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void createSubstitueBoxTable(void)
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{
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int i = 0;
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do {
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uint8_t temp;
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if (i > 0)
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temp = powTable[255 - logTable[i]];
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else
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temp = 0;
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uint8_t sb = temp ^ 0x63;
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for (int j = 0; j < 4; j++)
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{
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temp = (temp << 1) | (temp >> 7);
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sb ^= temp;
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}
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sbox[i] = sb;
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} while (++i != 0);
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}
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void createInverseSubstitueBoxTable(void)
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{
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uint8_t i = 0;
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uint8_t j = 0;
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do {
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do {
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if (sbox[j] == i)
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{
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isbox[i] = j;
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j = 255;
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}
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} while (++j != 0);
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} while (++i != 0);
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}
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*/
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// ***********************************************************************************
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void copy_block(void *d, void *s)
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{
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if (d == s) {
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return;
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}
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register uint8_t *src = s;
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register uint8_t *dest = d;
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for (int i = N_BLOCK; i; --i) {
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*dest++ = *src++;
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}
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}
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void xor_block(void *d, void *s)
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{
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register uint8_t *src = s;
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register uint8_t *dest = d;
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for (int i = N_BLOCK; i; --i) {
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*dest++ ^= *src++;
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}
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}
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void xor_word(uint8_t *d, uint8_t *s)
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{
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*d++ ^= *s++;
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*d++ ^= *s++;
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*d++ ^= *s++;
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*d++ ^= *s++;
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}
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void xor_sub_word(uint8_t *d, uint8_t *s)
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{
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*d++ ^= sbox[*s++];
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*d++ ^= sbox[*s++];
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*d++ ^= sbox[*s++];
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*d++ ^= sbox[*s++];
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}
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void xor_sub_rot_word(uint8_t *d, uint8_t *s, uint8_t rc)
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{
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*d++ ^= sbox[s[1]] ^ rc;
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*d++ ^= sbox[s[2]];
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*d++ ^= sbox[s[3]];
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*d++ ^= sbox[s[0]];
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}
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void mix_sub_column(uint8_t *a)
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{
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uint8_t a0 = a[0];
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uint8_t a1 = a[1];
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uint8_t a2 = a[2];
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uint8_t a3 = a[3];
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uint8_t tmp = a0 ^ a1 ^ a2 ^ a3;
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a[0] = a0 ^ xtime[a0 ^ a1] ^ tmp;
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a[1] = a1 ^ xtime[a1 ^ a2] ^ tmp;
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a[2] = a2 ^ xtime[a2 ^ a3] ^ tmp;
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a[3] = a3 ^ xtime[a3 ^ a0] ^ tmp;
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}
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void mix_sub_columns(void *a)
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{
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mix_sub_column((uint8_t *)a + 0);
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mix_sub_column((uint8_t *)a + 4);
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mix_sub_column((uint8_t *)a + 8);
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mix_sub_column((uint8_t *)a + 12);
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}
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void inv_mix_sub_column(uint8_t *a)
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{
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uint8_t tmp;
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tmp = xtime[xtime[a[0] ^ a[2]]];
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a[0] ^= tmp;
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a[2] ^= tmp;
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tmp = xtime[xtime[a[1] ^ a[3]]];
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a[1] ^= tmp;
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a[3] ^= tmp;
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}
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void inv_mix_sub_columns(void *a)
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{
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inv_mix_sub_column((uint8_t *)a + 0);
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inv_mix_sub_column((uint8_t *)a + 4);
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inv_mix_sub_column((uint8_t *)a + 8);
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inv_mix_sub_column((uint8_t *)a + 12);
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mix_sub_columns(a);
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}
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void shift_sub_rows(uint8_t *a)
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{
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uint8_t tmp;
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a[0] = sbox[a[0]];
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a[4] = sbox[a[4]];
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a[8] = sbox[a[8]];
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a[12] = sbox[a[12]];
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tmp = a[1];
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a[1] = sbox[a[5]];
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a[5] = sbox[a[9]];
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a[9] = sbox[a[13]];
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a[13] = sbox[tmp];
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tmp = a[2];
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a[2] = sbox[a[10]];
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a[10] = sbox[tmp];
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tmp = a[6];
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a[6] = sbox[a[14]];
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a[14] = sbox[tmp];
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tmp = a[15];
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a[15] = sbox[a[11]];
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a[11] = sbox[a[7]];
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a[7] = sbox[a[3]];
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a[3] = sbox[tmp];
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}
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void inv_shift_sub_rows(uint8_t *a)
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{
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uint8_t tmp;
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a[0] = isbox[a[0]];
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a[4] = isbox[a[4]];
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a[8] = isbox[a[8]];
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a[12] = isbox[a[12]];
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tmp = a[13];
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a[13] = isbox[a[9]];
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a[9] = isbox[a[5]];
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a[5] = isbox[a[1]];
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a[1] = isbox[tmp];
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tmp = a[2];
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a[2] = isbox[a[10]];
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a[10] = isbox[tmp];
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tmp = a[6];
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a[6] = isbox[a[14]];
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a[14] = isbox[tmp];
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tmp = a[3];
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a[3] = isbox[a[7]];
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a[7] = isbox[a[11]];
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a[11] = isbox[a[15]];
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a[15] = isbox[tmp];
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}
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// ***********************************************************************************
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// 'on the fly' encryption key update for 128 bit keys
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void update_encrypt_key_128(uint8_t *k, uint8_t *rc)
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{
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xor_sub_rot_word(k + 0, k + 12, *rc);
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*rc = (*rc << 1) ^ ((*rc & 0x80) ? BPOLY : 0);
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for (int i = 4; i < 16; i += 4) {
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xor_word(k + i + 0, k + i - 4);
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}
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}
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// Encrypt a single block of 16 bytes
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void aes_encrypt_cbc_128(void *data, void *key, void *chain_block)
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{
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uint8_t rc = 1;
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if (chain_block) {
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xor_block(data, chain_block);
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}
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for (int round = 10; round; --round) {
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xor_block(data, key); // add_round_key
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update_encrypt_key_128((uint8_t *)key, &rc);
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shift_sub_rows(data);
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if (round <= 1) {
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continue;
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}
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mix_sub_columns(data);
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}
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xor_block(data, key); // add_round_key
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if (chain_block) {
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copy_block(chain_block, data);
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}
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}
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// 'on the fly' decryption key update for 128 bit keys
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void update_decrypt_key_128(uint8_t *k, uint8_t *rc)
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{
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for (int i = 12; i; i -= 4) {
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xor_word(k + i + 0, k + i - 4);
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}
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*rc = (*rc >> 1) ^ ((*rc & 1) ? DPOLY : 0);
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xor_sub_rot_word(k + 0, k + 12, *rc);
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}
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// Decrypt a single block of 16 bytes
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void aes_decrypt_cbc_128(void *data, void *key, void *chain_block)
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{
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uint8_t tmp_data[N_BLOCK];
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uint8_t rc = 0x6c;
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|
|
copy_block(tmp_data, data);
|
|
|
|
xor_block(data, key); // add_round_key
|
|
for (int round = 10; round; --round) {
|
|
inv_shift_sub_rows(data);
|
|
update_decrypt_key_128(key, &rc);
|
|
xor_block(data, key); // add_round_key
|
|
if (round <= 1) {
|
|
continue;
|
|
}
|
|
inv_mix_sub_columns(data);
|
|
}
|
|
|
|
if (chain_block) {
|
|
xor_block(data, chain_block);
|
|
copy_block(chain_block, tmp_data);
|
|
}
|
|
}
|
|
|
|
void aes_decrypt_key_128_create(void *enc_key, void *dec_key)
|
|
{
|
|
copy_block(dec_key, enc_key);
|
|
|
|
uint8_t rc = 1;
|
|
for (int i = 0; i < 10; i++) {
|
|
update_encrypt_key_128(dec_key, &rc);
|
|
}
|
|
}
|
|
|
|
// ***********************************************************************************
|
|
|
|
// 'on the fly' encryption key update for 256 bit keys
|
|
void update_encrypt_key_256(uint8_t *k, uint8_t *rc)
|
|
{
|
|
xor_sub_rot_word(k + 0, k + 28, *rc);
|
|
|
|
*rc = (*rc << 1) ^ ((*rc & 0x80) ? BPOLY : 0);
|
|
|
|
for (int i = 4; i < 16; i += 4) {
|
|
xor_word(k + i + 0, k + i - 4);
|
|
}
|
|
|
|
xor_sub_word(k + 16, k + 12);
|
|
|
|
for (int i = 20; i < 32; i += 4) {
|
|
xor_word(k + i + 0, k + i - 4);
|
|
}
|
|
}
|
|
|
|
// Encrypt a single block of 16 bytes
|
|
void aes_encrypt_cbc_256(void *data, void *key, void *chain_block)
|
|
{
|
|
uint8_t rc = 1;
|
|
|
|
if (chain_block) {
|
|
xor_block(data, chain_block);
|
|
}
|
|
|
|
for (int round = 7; round; --round) {
|
|
// printf("key - ");
|
|
// uint8_t *p = key;
|
|
// for (int i = 0; i < 32; i++) printf("%0.2X ", *p++);
|
|
// printf("\r\n");
|
|
|
|
xor_block(data, key); // add_round_key
|
|
shift_sub_rows(data);
|
|
mix_sub_columns(data);
|
|
xor_block(data, (uint8_t *)key + 16); // add_round_key
|
|
update_encrypt_key_256(key, &rc);
|
|
shift_sub_rows(data);
|
|
if (round <= 1) {
|
|
continue;
|
|
}
|
|
mix_sub_columns(data);
|
|
}
|
|
xor_block(data, key); // add_round_key
|
|
|
|
if (chain_block) {
|
|
copy_block(chain_block, data);
|
|
}
|
|
}
|
|
|
|
// 'on the fly' decryption key update for 256 bit keys
|
|
void update_decrypt_key_256(uint8_t *k, uint8_t *rc)
|
|
{
|
|
for (int i = 28; i >= 20; i -= 4) {
|
|
xor_word(k + i + 0, k + i - 4);
|
|
}
|
|
|
|
xor_sub_word(k + 16, k + 12);
|
|
|
|
for (int i = 12; i; i -= 4) {
|
|
xor_word(k + i + 0, k + i - 4);
|
|
}
|
|
|
|
*rc = (*rc >> 1) ^ ((*rc & 1) ? DPOLY : 0);
|
|
|
|
xor_sub_rot_word(k + 0, k + 28, *rc);
|
|
}
|
|
|
|
// Decrypt a single block of 16 bytes
|
|
void aes_decrypt_cbc_256(void *data, void *key, void *chain_block)
|
|
{
|
|
uint8_t tmp_data[N_BLOCK];
|
|
|
|
uint8_t rc = 0x80;
|
|
|
|
copy_block(tmp_data, data);
|
|
|
|
xor_block(data, key); // add_round_key
|
|
for (int round = 7; round; --round) {
|
|
inv_shift_sub_rows(data);
|
|
update_decrypt_key_256(key, &rc);
|
|
xor_block(data, (uint8_t *)key + 16); // add_round_key
|
|
inv_mix_sub_columns(data);
|
|
inv_shift_sub_rows(data);
|
|
xor_block(data, key); // add_round_key
|
|
if (round <= 1) {
|
|
continue;
|
|
}
|
|
inv_mix_sub_columns(data);
|
|
}
|
|
|
|
if (chain_block) {
|
|
xor_block(data, chain_block);
|
|
copy_block(chain_block, tmp_data);
|
|
}
|
|
}
|
|
|
|
void aes_decrypt_key_256_create(void *enc_key, void *dec_key)
|
|
{
|
|
if (dec_key != enc_key) {
|
|
copy_block(dec_key, enc_key);
|
|
copy_block((uint8_t *)dec_key + 16, (uint8_t *)enc_key + 16);
|
|
}
|
|
|
|
uint8_t rc = 1;
|
|
for (int i = 7; i; --i) {
|
|
update_encrypt_key_256(dec_key, &rc);
|
|
}
|
|
}
|
|
|
|
// ***********************************************************************************
|