security.cpp

00001 /*****************************************************************************
00002 *
00003 *  security.c  - CC3000 Host Driver Implementation.
00004 *  Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/
00005 *
00006 *  Redistribution and use in source and binary forms, with or without
00007 *  modification, are permitted provided that the following conditions
00008 *  are met:
00009 *
00010 *    Redistributions of source code must retain the above copyright
00011 *    notice, this list of conditions and the following disclaimer.
00012 *
00013 *    Redistributions in binary form must reproduce the above copyright
00014 *    notice, this list of conditions and the following disclaimer in the
00015 *    documentation and/or other materials provided with the   
00016 *    distribution.
00017 *
00018 *    Neither the name of Texas Instruments Incorporated nor the names of
00019 *    its contributors may be used to endorse or promote products derived
00020 *    from this software without specific prior written permission.
00021 *
00022 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
00023 *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
00024 *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
00025 *  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 
00026 *  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
00027 *  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 
00028 *  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
00029 *  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
00030 *  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
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00032 *  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
00033 *
00034 *****************************************************************************/
00035 
00036 //*****************************************************************************
00037 //
00038 //! \addtogroup security_api
00039 //! @{
00040 //
00041 //*****************************************************************************
00042 
00043 #include "security.h"
00044 
00045 #ifndef CC3000_UNENCRYPTED_SMART_CONFIG
00046 // foreward sbox
00047 const unsigned char sbox[256] =   { 
00048 //0     1    2      3     4    5     6     7      8    9     A      B    C     D     E     F
00049 0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, 0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76, //0
00050 0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0, 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0, //1
00051 0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc, 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15, //2
00052 0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75, //3
00053 0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84, //4
00054 0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b, 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf, //5
00055 0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8, //6
00056 0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2, //7
00057 0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17, 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73, //8
00058 0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, 0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb, //9
00059 0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c, 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79, //A
00060 0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9, 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08, //B
00061 0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6, 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a, //C
00062 0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e, 0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e, //D
00063 0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94, 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf, //E
00064 0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, 0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16 }; //F   
00065 // inverse sbox
00066 const unsigned char rsbox[256] =
00067 { 0x52, 0x09, 0x6a, 0xd5, 0x30, 0x36, 0xa5, 0x38, 0xbf, 0x40, 0xa3, 0x9e, 0x81, 0xf3, 0xd7, 0xfb
00068 , 0x7c, 0xe3, 0x39, 0x82, 0x9b, 0x2f, 0xff, 0x87, 0x34, 0x8e, 0x43, 0x44, 0xc4, 0xde, 0xe9, 0xcb
00069 , 0x54, 0x7b, 0x94, 0x32, 0xa6, 0xc2, 0x23, 0x3d, 0xee, 0x4c, 0x95, 0x0b, 0x42, 0xfa, 0xc3, 0x4e
00070 , 0x08, 0x2e, 0xa1, 0x66, 0x28, 0xd9, 0x24, 0xb2, 0x76, 0x5b, 0xa2, 0x49, 0x6d, 0x8b, 0xd1, 0x25
00071 , 0x72, 0xf8, 0xf6, 0x64, 0x86, 0x68, 0x98, 0x16, 0xd4, 0xa4, 0x5c, 0xcc, 0x5d, 0x65, 0xb6, 0x92
00072 , 0x6c, 0x70, 0x48, 0x50, 0xfd, 0xed, 0xb9, 0xda, 0x5e, 0x15, 0x46, 0x57, 0xa7, 0x8d, 0x9d, 0x84
00073 , 0x90, 0xd8, 0xab, 0x00, 0x8c, 0xbc, 0xd3, 0x0a, 0xf7, 0xe4, 0x58, 0x05, 0xb8, 0xb3, 0x45, 0x06
00074 , 0xd0, 0x2c, 0x1e, 0x8f, 0xca, 0x3f, 0x0f, 0x02, 0xc1, 0xaf, 0xbd, 0x03, 0x01, 0x13, 0x8a, 0x6b
00075 , 0x3a, 0x91, 0x11, 0x41, 0x4f, 0x67, 0xdc, 0xea, 0x97, 0xf2, 0xcf, 0xce, 0xf0, 0xb4, 0xe6, 0x73
00076 , 0x96, 0xac, 0x74, 0x22, 0xe7, 0xad, 0x35, 0x85, 0xe2, 0xf9, 0x37, 0xe8, 0x1c, 0x75, 0xdf, 0x6e
00077 , 0x47, 0xf1, 0x1a, 0x71, 0x1d, 0x29, 0xc5, 0x89, 0x6f, 0xb7, 0x62, 0x0e, 0xaa, 0x18, 0xbe, 0x1b
00078 , 0xfc, 0x56, 0x3e, 0x4b, 0xc6, 0xd2, 0x79, 0x20, 0x9a, 0xdb, 0xc0, 0xfe, 0x78, 0xcd, 0x5a, 0xf4
00079 , 0x1f, 0xdd, 0xa8, 0x33, 0x88, 0x07, 0xc7, 0x31, 0xb1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xec, 0x5f
00080 , 0x60, 0x51, 0x7f, 0xa9, 0x19, 0xb5, 0x4a, 0x0d, 0x2d, 0xe5, 0x7a, 0x9f, 0x93, 0xc9, 0x9c, 0xef
00081 , 0xa0, 0xe0, 0x3b, 0x4d, 0xae, 0x2a, 0xf5, 0xb0, 0xc8, 0xeb, 0xbb, 0x3c, 0x83, 0x53, 0x99, 0x61
00082 , 0x17, 0x2b, 0x04, 0x7e, 0xba, 0x77, 0xd6, 0x26, 0xe1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0c, 0x7d };
00083 // round constant
00084 const unsigned char Rcon[11] = {
00085   0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36};
00086 
00087 
00088 unsigned char expandedKey[176];
00089 
00090 //*****************************************************************************
00091 //
00092 //!  expandKey
00093 //!
00094 //!  @param  key          AES128 key - 16 bytes
00095 //!  @param  expandedKey  expanded AES128 key
00096 //!
00097 //!  @return  none
00098 //!
00099 //!  @brief  expend a 16 bytes key for AES128 implementation
00100 //!
00101 //*****************************************************************************
00102 
00103 void expandKey(unsigned char *expandedKey,
00104                unsigned char *key)
00105 {
00106   unsigned short ii, buf1;
00107   for (ii=0;ii<16;ii++)
00108     expandedKey[ii] = key[ii];
00109   for (ii=1;ii<11;ii++){
00110     buf1 = expandedKey[ii*16 - 4];
00111     expandedKey[ii*16 + 0] = sbox[expandedKey[ii*16 - 3]]^expandedKey[(ii-1)*16 + 0]^Rcon[ii];
00112     expandedKey[ii*16 + 1] = sbox[expandedKey[ii*16 - 2]]^expandedKey[(ii-1)*16 + 1];
00113     expandedKey[ii*16 + 2] = sbox[expandedKey[ii*16 - 1]]^expandedKey[(ii-1)*16 + 2];
00114     expandedKey[ii*16 + 3] = sbox[buf1                  ]^expandedKey[(ii-1)*16 + 3];
00115     expandedKey[ii*16 + 4] = expandedKey[(ii-1)*16 + 4]^expandedKey[ii*16 + 0];
00116     expandedKey[ii*16 + 5] = expandedKey[(ii-1)*16 + 5]^expandedKey[ii*16 + 1];
00117     expandedKey[ii*16 + 6] = expandedKey[(ii-1)*16 + 6]^expandedKey[ii*16 + 2];
00118     expandedKey[ii*16 + 7] = expandedKey[(ii-1)*16 + 7]^expandedKey[ii*16 + 3];
00119     expandedKey[ii*16 + 8] = expandedKey[(ii-1)*16 + 8]^expandedKey[ii*16 + 4];
00120     expandedKey[ii*16 + 9] = expandedKey[(ii-1)*16 + 9]^expandedKey[ii*16 + 5];
00121     expandedKey[ii*16 +10] = expandedKey[(ii-1)*16 +10]^expandedKey[ii*16 + 6];
00122     expandedKey[ii*16 +11] = expandedKey[(ii-1)*16 +11]^expandedKey[ii*16 + 7];
00123     expandedKey[ii*16 +12] = expandedKey[(ii-1)*16 +12]^expandedKey[ii*16 + 8];
00124     expandedKey[ii*16 +13] = expandedKey[(ii-1)*16 +13]^expandedKey[ii*16 + 9];
00125     expandedKey[ii*16 +14] = expandedKey[(ii-1)*16 +14]^expandedKey[ii*16 +10];
00126     expandedKey[ii*16 +15] = expandedKey[(ii-1)*16 +15]^expandedKey[ii*16 +11];
00127   }
00128     
00129 }
00130 
00131 //*****************************************************************************
00132 //
00133 //!  galois_mul2
00134 //!
00135 //!  @param  value    argument to multiply
00136 //!
00137 //!  @return  multiplied argument
00138 //!
00139 //!  @brief  multiply by 2 in the galois field
00140 //!
00141 //*****************************************************************************
00142 
00143 unsigned char galois_mul2(unsigned char value)
00144 {
00145     if (value>>7)
00146     {
00147         value = value << 1;
00148         return (value^0x1b);
00149     } else
00150         return value<<1;
00151 }
00152 
00153 //*****************************************************************************
00154 //
00155 //!  aes_encr
00156 //!
00157 //!  @param[in]  expandedKey expanded AES128 key
00158 //!  @param[in/out] state 16 bytes of plain text and cipher text
00159 //!
00160 //!  @return  none
00161 //!
00162 //!  @brief   internal implementation of AES128 encryption.
00163 //!           straight forward aes encryption implementation
00164 //!           first the group of operations
00165 //!          - addRoundKey
00166 //!          - subbytes
00167 //!          - shiftrows
00168 //!          - mixcolums
00169 //!          is executed 9 times, after this addroundkey to finish the 9th 
00170 //!          round, after that the 10th round without mixcolums
00171 //!          no further subfunctions to save cycles for function calls
00172 //!          no structuring with "for (....)" to save cycles.
00173 //!     
00174 //!
00175 //*****************************************************************************
00176 
00177 void aes_encr(unsigned char *state, unsigned char *expandedKey)
00178 {
00179   unsigned char buf1, buf2, buf3, round;
00180         
00181   for (round = 0; round < 9; round ++){
00182     // addroundkey, sbox and shiftrows
00183     // row 0
00184     state[ 0]  = sbox[(state[ 0] ^ expandedKey[(round*16)     ])];
00185     state[ 4]  = sbox[(state[ 4] ^ expandedKey[(round*16) +  4])];
00186     state[ 8]  = sbox[(state[ 8] ^ expandedKey[(round*16) +  8])];
00187     state[12]  = sbox[(state[12] ^ expandedKey[(round*16) + 12])];
00188     // row 1
00189     buf1 = state[1] ^ expandedKey[(round*16) + 1];
00190     state[ 1]  = sbox[(state[ 5] ^ expandedKey[(round*16) +  5])];
00191     state[ 5]  = sbox[(state[ 9] ^ expandedKey[(round*16) +  9])];
00192     state[ 9]  = sbox[(state[13] ^ expandedKey[(round*16) + 13])];
00193     state[13]  = sbox[buf1];
00194     // row 2
00195     buf1 = state[2] ^ expandedKey[(round*16) + 2];
00196     buf2 = state[6] ^ expandedKey[(round*16) + 6];
00197     state[ 2]  = sbox[(state[10] ^ expandedKey[(round*16) + 10])];
00198     state[ 6]  = sbox[(state[14] ^ expandedKey[(round*16) + 14])];
00199     state[10]  = sbox[buf1];
00200     state[14]  = sbox[buf2];
00201     // row 3
00202     buf1 = state[15] ^ expandedKey[(round*16) + 15];
00203     state[15]  = sbox[(state[11] ^ expandedKey[(round*16) + 11])];
00204     state[11]  = sbox[(state[ 7] ^ expandedKey[(round*16) +  7])];
00205     state[ 7]  = sbox[(state[ 3] ^ expandedKey[(round*16) +  3])];
00206     state[ 3]  = sbox[buf1];
00207     
00208     // mixcolums //////////
00209     // col1
00210     buf1 = state[0] ^ state[1] ^ state[2] ^ state[3];
00211     buf2 = state[0];
00212     buf3 = state[0]^state[1]; buf3=galois_mul2(buf3); state[0] = state[0] ^ buf3 ^ buf1;
00213     buf3 = state[1]^state[2]; buf3=galois_mul2(buf3); state[1] = state[1] ^ buf3 ^ buf1;
00214     buf3 = state[2]^state[3]; buf3=galois_mul2(buf3); state[2] = state[2] ^ buf3 ^ buf1;
00215     buf3 = state[3]^buf2;     buf3=galois_mul2(buf3); state[3] = state[3] ^ buf3 ^ buf1;
00216     // col2
00217     buf1 = state[4] ^ state[5] ^ state[6] ^ state[7];
00218     buf2 = state[4];
00219     buf3 = state[4]^state[5]; buf3=galois_mul2(buf3); state[4] = state[4] ^ buf3 ^ buf1;
00220     buf3 = state[5]^state[6]; buf3=galois_mul2(buf3); state[5] = state[5] ^ buf3 ^ buf1;
00221     buf3 = state[6]^state[7]; buf3=galois_mul2(buf3); state[6] = state[6] ^ buf3 ^ buf1;
00222     buf3 = state[7]^buf2;     buf3=galois_mul2(buf3); state[7] = state[7] ^ buf3 ^ buf1;
00223     // col3
00224     buf1 = state[8] ^ state[9] ^ state[10] ^ state[11];
00225     buf2 = state[8];
00226     buf3 = state[8]^state[9];   buf3=galois_mul2(buf3); state[8] = state[8] ^ buf3 ^ buf1;
00227     buf3 = state[9]^state[10];  buf3=galois_mul2(buf3); state[9] = state[9] ^ buf3 ^ buf1;
00228     buf3 = state[10]^state[11]; buf3=galois_mul2(buf3); state[10] = state[10] ^ buf3 ^ buf1;
00229     buf3 = state[11]^buf2;      buf3=galois_mul2(buf3); state[11] = state[11] ^ buf3 ^ buf1;
00230     // col4
00231     buf1 = state[12] ^ state[13] ^ state[14] ^ state[15];
00232     buf2 = state[12];
00233     buf3 = state[12]^state[13]; buf3=galois_mul2(buf3); state[12] = state[12] ^ buf3 ^ buf1;
00234     buf3 = state[13]^state[14]; buf3=galois_mul2(buf3); state[13] = state[13] ^ buf3 ^ buf1;
00235     buf3 = state[14]^state[15]; buf3=galois_mul2(buf3); state[14] = state[14] ^ buf3 ^ buf1;
00236     buf3 = state[15]^buf2;      buf3=galois_mul2(buf3); state[15] = state[15] ^ buf3 ^ buf1;    
00237         
00238   }
00239   // 10th round without mixcols
00240   state[ 0]  = sbox[(state[ 0] ^ expandedKey[(round*16)     ])];
00241   state[ 4]  = sbox[(state[ 4] ^ expandedKey[(round*16) +  4])];
00242   state[ 8]  = sbox[(state[ 8] ^ expandedKey[(round*16) +  8])];
00243   state[12]  = sbox[(state[12] ^ expandedKey[(round*16) + 12])];
00244   // row 1
00245   buf1 = state[1] ^ expandedKey[(round*16) + 1];
00246   state[ 1]  = sbox[(state[ 5] ^ expandedKey[(round*16) +  5])];
00247   state[ 5]  = sbox[(state[ 9] ^ expandedKey[(round*16) +  9])];
00248   state[ 9]  = sbox[(state[13] ^ expandedKey[(round*16) + 13])];
00249   state[13]  = sbox[buf1];
00250   // row 2
00251   buf1 = state[2] ^ expandedKey[(round*16) + 2];
00252   buf2 = state[6] ^ expandedKey[(round*16) + 6];
00253   state[ 2]  = sbox[(state[10] ^ expandedKey[(round*16) + 10])];
00254   state[ 6]  = sbox[(state[14] ^ expandedKey[(round*16) + 14])];
00255   state[10]  = sbox[buf1];
00256   state[14]  = sbox[buf2];
00257   // row 3
00258   buf1 = state[15] ^ expandedKey[(round*16) + 15];
00259   state[15]  = sbox[(state[11] ^ expandedKey[(round*16) + 11])];
00260   state[11]  = sbox[(state[ 7] ^ expandedKey[(round*16) +  7])];
00261   state[ 7]  = sbox[(state[ 3] ^ expandedKey[(round*16) +  3])];
00262   state[ 3]  = sbox[buf1];
00263   // last addroundkey
00264   state[ 0]^=expandedKey[160];
00265   state[ 1]^=expandedKey[161];
00266   state[ 2]^=expandedKey[162];
00267   state[ 3]^=expandedKey[163];
00268   state[ 4]^=expandedKey[164];
00269   state[ 5]^=expandedKey[165];
00270   state[ 6]^=expandedKey[166];
00271   state[ 7]^=expandedKey[167];
00272   state[ 8]^=expandedKey[168];
00273   state[ 9]^=expandedKey[169];
00274   state[10]^=expandedKey[170];
00275   state[11]^=expandedKey[171];
00276   state[12]^=expandedKey[172];
00277   state[13]^=expandedKey[173];
00278   state[14]^=expandedKey[174]; 
00279   state[15]^=expandedKey[175];
00280 } 
00281 
00282 //*****************************************************************************
00283 //
00284 //!  aes_decr
00285 //!
00286 //!  @param[in]  expandedKey expanded AES128 key
00287 //!  @param[in\out] state 16 bytes of cipher text and plain text
00288 //!
00289 //!  @return  none
00290 //!
00291 //!  @brief   internal implementation of AES128 decryption.
00292 //!           straight forward aes decryption implementation
00293 //!           the order of substeps is the exact reverse of decryption
00294 //!           inverse functions:
00295 //!            - addRoundKey is its own inverse
00296 //!            - rsbox is inverse of sbox
00297 //!            - rightshift instead of leftshift
00298 //!            - invMixColumns = barreto + mixColumns
00299 //!           no further subfunctions to save cycles for function calls
00300 //!           no structuring with "for (....)" to save cycles
00301 //!
00302 //*****************************************************************************
00303 
00304 void aes_decr(unsigned char *state, unsigned char *expandedKey)
00305 {
00306   unsigned char buf1, buf2, buf3;
00307   signed char round;
00308   round = 9;
00309     
00310   // initial addroundkey
00311   state[ 0]^=expandedKey[160];
00312   state[ 1]^=expandedKey[161];
00313   state[ 2]^=expandedKey[162];
00314   state[ 3]^=expandedKey[163];
00315   state[ 4]^=expandedKey[164];
00316   state[ 5]^=expandedKey[165];
00317   state[ 6]^=expandedKey[166];
00318   state[ 7]^=expandedKey[167];
00319   state[ 8]^=expandedKey[168];
00320   state[ 9]^=expandedKey[169];
00321   state[10]^=expandedKey[170];
00322   state[11]^=expandedKey[171];
00323   state[12]^=expandedKey[172];
00324   state[13]^=expandedKey[173];
00325   state[14]^=expandedKey[174]; 
00326   state[15]^=expandedKey[175];
00327     
00328   // 10th round without mixcols
00329   state[ 0]  = rsbox[state[ 0]] ^ expandedKey[(round*16)     ];
00330   state[ 4]  = rsbox[state[ 4]] ^ expandedKey[(round*16) +  4];
00331   state[ 8]  = rsbox[state[ 8]] ^ expandedKey[(round*16) +  8];
00332   state[12]  = rsbox[state[12]] ^ expandedKey[(round*16) + 12];
00333   // row 1
00334   buf1 =       rsbox[state[13]] ^ expandedKey[(round*16) +  1];
00335   state[13]  = rsbox[state[ 9]] ^ expandedKey[(round*16) + 13];
00336   state[ 9]  = rsbox[state[ 5]] ^ expandedKey[(round*16) +  9];
00337   state[ 5]  = rsbox[state[ 1]] ^ expandedKey[(round*16) +  5];
00338   state[ 1]  = buf1;
00339   // row 2
00340   buf1 =       rsbox[state[ 2]] ^ expandedKey[(round*16) + 10];
00341   buf2 =       rsbox[state[ 6]] ^ expandedKey[(round*16) + 14];
00342   state[ 2]  = rsbox[state[10]] ^ expandedKey[(round*16) +  2];
00343   state[ 6]  = rsbox[state[14]] ^ expandedKey[(round*16) +  6];
00344   state[10]  = buf1;
00345   state[14]  = buf2;
00346   // row 3
00347   buf1 =       rsbox[state[ 3]] ^ expandedKey[(round*16) + 15];
00348   state[ 3]  = rsbox[state[ 7]] ^ expandedKey[(round*16) +  3];
00349   state[ 7]  = rsbox[state[11]] ^ expandedKey[(round*16) +  7];
00350   state[11]  = rsbox[state[15]] ^ expandedKey[(round*16) + 11];
00351   state[15]  = buf1;
00352     
00353   for (round = 8; round >= 0; round--){
00354     // barreto
00355     //col1
00356     buf1 = galois_mul2(galois_mul2(state[0]^state[2]));
00357     buf2 = galois_mul2(galois_mul2(state[1]^state[3]));
00358     state[0] ^= buf1;     state[1] ^= buf2;    state[2] ^= buf1;    state[3] ^= buf2;
00359     //col2
00360     buf1 = galois_mul2(galois_mul2(state[4]^state[6]));
00361     buf2 = galois_mul2(galois_mul2(state[5]^state[7]));
00362     state[4] ^= buf1;    state[5] ^= buf2;    state[6] ^= buf1;    state[7] ^= buf2;
00363     //col3
00364     buf1 = galois_mul2(galois_mul2(state[8]^state[10]));
00365     buf2 = galois_mul2(galois_mul2(state[9]^state[11]));
00366     state[8] ^= buf1;    state[9] ^= buf2;    state[10] ^= buf1;    state[11] ^= buf2;
00367     //col4
00368     buf1 = galois_mul2(galois_mul2(state[12]^state[14]));
00369     buf2 = galois_mul2(galois_mul2(state[13]^state[15]));
00370     state[12] ^= buf1;    state[13] ^= buf2;    state[14] ^= buf1;    state[15] ^= buf2;
00371     // mixcolums //////////
00372     // col1
00373     buf1 = state[0] ^ state[1] ^ state[2] ^ state[3];
00374     buf2 = state[0];
00375     buf3 = state[0]^state[1]; buf3=galois_mul2(buf3); state[0] = state[0] ^ buf3 ^ buf1;
00376     buf3 = state[1]^state[2]; buf3=galois_mul2(buf3); state[1] = state[1] ^ buf3 ^ buf1;
00377     buf3 = state[2]^state[3]; buf3=galois_mul2(buf3); state[2] = state[2] ^ buf3 ^ buf1;
00378     buf3 = state[3]^buf2;     buf3=galois_mul2(buf3); state[3] = state[3] ^ buf3 ^ buf1;
00379     // col2
00380     buf1 = state[4] ^ state[5] ^ state[6] ^ state[7];
00381     buf2 = state[4];
00382     buf3 = state[4]^state[5]; buf3=galois_mul2(buf3); state[4] = state[4] ^ buf3 ^ buf1;
00383     buf3 = state[5]^state[6]; buf3=galois_mul2(buf3); state[5] = state[5] ^ buf3 ^ buf1;
00384     buf3 = state[6]^state[7]; buf3=galois_mul2(buf3); state[6] = state[6] ^ buf3 ^ buf1;
00385     buf3 = state[7]^buf2;     buf3=galois_mul2(buf3); state[7] = state[7] ^ buf3 ^ buf1;
00386     // col3
00387     buf1 = state[8] ^ state[9] ^ state[10] ^ state[11];
00388     buf2 = state[8];
00389     buf3 = state[8]^state[9];   buf3=galois_mul2(buf3); state[8] = state[8] ^ buf3 ^ buf1;
00390     buf3 = state[9]^state[10];  buf3=galois_mul2(buf3); state[9] = state[9] ^ buf3 ^ buf1;
00391     buf3 = state[10]^state[11]; buf3=galois_mul2(buf3); state[10] = state[10] ^ buf3 ^ buf1;
00392     buf3 = state[11]^buf2;      buf3=galois_mul2(buf3); state[11] = state[11] ^ buf3 ^ buf1;
00393     // col4
00394     buf1 = state[12] ^ state[13] ^ state[14] ^ state[15];
00395     buf2 = state[12];
00396     buf3 = state[12]^state[13]; buf3=galois_mul2(buf3); state[12] = state[12] ^ buf3 ^ buf1;
00397     buf3 = state[13]^state[14]; buf3=galois_mul2(buf3); state[13] = state[13] ^ buf3 ^ buf1;
00398     buf3 = state[14]^state[15]; buf3=galois_mul2(buf3); state[14] = state[14] ^ buf3 ^ buf1;
00399     buf3 = state[15]^buf2;      buf3=galois_mul2(buf3); state[15] = state[15] ^ buf3 ^ buf1;    
00400         
00401     // addroundkey, rsbox and shiftrows
00402     // row 0
00403     state[ 0]  = rsbox[state[ 0]] ^ expandedKey[(round*16)     ];
00404     state[ 4]  = rsbox[state[ 4]] ^ expandedKey[(round*16) +  4];
00405     state[ 8]  = rsbox[state[ 8]] ^ expandedKey[(round*16) +  8];
00406     state[12]  = rsbox[state[12]] ^ expandedKey[(round*16) + 12];
00407     // row 1
00408     buf1 =       rsbox[state[13]] ^ expandedKey[(round*16) +  1];
00409     state[13]  = rsbox[state[ 9]] ^ expandedKey[(round*16) + 13];
00410     state[ 9]  = rsbox[state[ 5]] ^ expandedKey[(round*16) +  9];
00411     state[ 5]  = rsbox[state[ 1]] ^ expandedKey[(round*16) +  5];
00412     state[ 1]  = buf1;
00413     // row 2
00414     buf1 =       rsbox[state[ 2]] ^ expandedKey[(round*16) + 10];
00415     buf2 =       rsbox[state[ 6]] ^ expandedKey[(round*16) + 14];
00416     state[ 2]  = rsbox[state[10]] ^ expandedKey[(round*16) +  2];
00417     state[ 6]  = rsbox[state[14]] ^ expandedKey[(round*16) +  6];
00418     state[10]  = buf1;
00419     state[14]  = buf2;
00420     // row 3
00421     buf1 =       rsbox[state[ 3]] ^ expandedKey[(round*16) + 15];
00422     state[ 3]  = rsbox[state[ 7]] ^ expandedKey[(round*16) +  3];
00423     state[ 7]  = rsbox[state[11]] ^ expandedKey[(round*16) +  7];
00424     state[11]  = rsbox[state[15]] ^ expandedKey[(round*16) + 11];
00425     state[15]  = buf1;
00426   }
00427     
00428 } 
00429 
00430 //*****************************************************************************
00431 //
00432 //!  aes_encrypt
00433 //!
00434 //!  @param[in]  key   AES128 key of size 16 bytes
00435 //!  @param[in\out] state   16 bytes of plain text and cipher text
00436 //!
00437 //!  @return  none
00438 //!
00439 //!  @brief   AES128 encryption:
00440 //!           Given AES128 key and  16 bytes plain text, cipher text of 16 bytes
00441 //!           is computed. The AES implementation is in mode ECB (Electronic 
00442 //!           Code Book). 
00443 //!     
00444 //!
00445 //*****************************************************************************
00446 
00447 void aes_encrypt(unsigned char *state,
00448                  unsigned char *key)
00449 {
00450     // expand the key into 176 bytes
00451     expandKey(expandedKey, key);       
00452     aes_encr(state, expandedKey);
00453 }
00454 
00455 //*****************************************************************************
00456 //
00457 //!  aes_decrypt
00458 //!
00459 //!  @param[in]  key   AES128 key of size 16 bytes
00460 //!  @param[in\out] state   16 bytes of cipher text and plain text
00461 //!
00462 //!  @return  none
00463 //!
00464 //!  @brief   AES128 decryption:
00465 //!           Given AES128 key and  16 bytes cipher text, plain text of 16 bytes
00466 //!           is computed The AES implementation is in mode ECB 
00467 //!           (Electronic Code Book).
00468 //!     
00469 //!
00470 //*****************************************************************************
00471 
00472 void aes_decrypt(unsigned char *state,
00473                  unsigned char *key)
00474 {
00475     expandKey(expandedKey, key);       // expand the key into 176 bytes
00476     aes_decr(state, expandedKey);
00477 }
00478 
00479 //*****************************************************************************
00480 //
00481 //!  aes_read_key
00482 //!
00483 //!  @param[out]  key   AES128 key of size 16 bytes
00484 //!
00485 //!  @return  on success 0, error otherwise.
00486 //!
00487 //!  @brief   Reads AES128 key from EEPROM
00488 //!           Reads the AES128 key from fileID #12 in EEPROM
00489 //!           returns an error if the key does not exist. 
00490 //!     
00491 //!
00492 //*****************************************************************************
00493 
00494 signed long aes_read_key(unsigned char *key)
00495 {
00496     signed long    returnValue;
00497     
00498     returnValue = nvmem_read(NVMEM_AES128_KEY_FILEID, AES128_KEY_SIZE, 0, key);
00499 
00500     return returnValue;
00501 }
00502 
00503 //*****************************************************************************
00504 //
00505 //!  aes_write_key
00506 //!
00507 //!  @param[out]  key   AES128 key of size 16 bytes
00508 //!
00509 //!  @return  on success 0, error otherwise.
00510 //!
00511 //!  @brief   writes AES128 key from EEPROM
00512 //!           Writes the AES128 key to fileID #12 in EEPROM
00513 //!     
00514 //!
00515 //*****************************************************************************
00516 
00517 signed long aes_write_key(unsigned char *key)
00518 {
00519     signed long    returnValue;
00520 
00521     returnValue = nvmem_write(NVMEM_AES128_KEY_FILEID, AES128_KEY_SIZE, 0, key);
00522 
00523     return returnValue;
00524 }
00525 
00526 #endif //CC3000_UNENCRYPTED_SMART_CONFIG
00527 
00528 //*****************************************************************************
00529 //
00530 // Close the Doxygen group.
00531 //! @}
00532 //
00533 //*****************************************************************************
00534