mvAesAlg.c File Reference

#include "mvOs.h"
#include "mvAesAlg.h"
#include "mvAesBoxes.dat"

Include dependency graph for mvAesAlg.c:

Go to the source code of this file.

Macros
#define	mul(aa, bb)   (mask[bb] & Alogtable[aa + Logtable[bb]])

Functions
MV_U8	mul1 (MV_U8 aa, MV_U8 bb)
void	KeyAddition (MV_U8 a[4][MAXBC], MV_U8 rk[4][MAXBC], MV_U8 BC)
void	ShiftRow128Enc (MV_U8 a[4][MAXBC])
void	ShiftRow128Dec (MV_U8 a[4][MAXBC])
void	Substitution (MV_U8 a[4][MAXBC], MV_U8 box[256])
void	MixColumn (MV_U8 a[4][MAXBC], MV_U8 rk[4][MAXBC])
void	InvMixColumn (MV_U8 a[4][MAXBC])
int	rijndaelKeySched (MV_U8 k[4][MAXKC], int keyBits, int blockBits, MV_U8 W[MAXROUNDS+1][4][MAXBC])
int	rijndaelEncrypt128 (MV_U8 a[4][MAXBC], MV_U8 rk[MAXROUNDS+1][4][MAXBC], int rounds)
int	rijndaelDecrypt128 (MV_U8 a[4][MAXBC], MV_U8 rk[MAXROUNDS+1][4][MAXBC], int rounds)

Macro Definition Documentation

mul

#define mul	(		aa,
			bb
	)		(mask[bb] & Alogtable[aa + Logtable[bb]])

Definition at line 25 of file mvAesAlg.c.

Function Documentation

InvMixColumn()

void InvMixColumn

(

MV_U8

a[4][MAXBC]

)

Definition at line 161 of file mvAesAlg.c.

                                     {
        /* Mix the four bytes of every column in a linear way
     * This is the opposite operation of Mixcolumn
     */
    MV_U8 b[4][MAXBC];
    int i, j;
 
    for(j = 0; j < 4; j++){
        b[0][j] = mul(223,a[0][j]) ^ mul(104,a[1][j]) ^ mul(238,a[2][j]) ^ mul(199,a[3][j]);
        b[1][j] = mul(223,a[1][j]) ^ mul(104,a[2][j]) ^ mul(238,a[3][j]) ^ mul(199,a[0][j]);
        b[2][j] = mul(223,a[2][j]) ^ mul(104,a[3][j]) ^ mul(238,a[0][j]) ^ mul(199,a[1][j]);
        b[3][j] = mul(223,a[3][j]) ^ mul(104,a[0][j]) ^ mul(238,a[1][j]) ^ mul(199,a[2][j]);
    }
    for(i = 0; i < 4; i++)
        /*for(j = 0; j < BC; j++) a[i][j] = b[i][j];*/
        ((MV_U32*)(&(a[i][0])))[0] = ((MV_U32*)(&(b[i][0])))[0];
}

Referenced by rijndaelDecrypt128().

KeyAddition()

void KeyAddition	(	MV_U8	a[4][MAXBC],
		MV_U8	rk[4][MAXBC],
		MV_U8	BC
	)

Definition at line 33 of file mvAesAlg.c.

{
    /* Exor corresponding text input and round key input bytes
     */
    ((MV_U32*)(&(a[0][0])))[0] ^= ((MV_U32*)(&(rk[0][0])))[0];
    ((MV_U32*)(&(a[1][0])))[0] ^= ((MV_U32*)(&(rk[1][0])))[0];
    ((MV_U32*)(&(a[2][0])))[0] ^= ((MV_U32*)(&(rk[2][0])))[0];
    ((MV_U32*)(&(a[3][0])))[0] ^= ((MV_U32*)(&(rk[3][0])))[0];
 
}

Referenced by rijndaelDecrypt128(), and rijndaelEncrypt128().

MixColumn()

void MixColumn	(	MV_U8	a[4][MAXBC],
		MV_U8	rk[4][MAXBC]
	)

Definition at line 144 of file mvAesAlg.c.

                                                      {
        /* Mix the four bytes of every column in a linear way
     */
    MV_U8 b[4][MAXBC];
    int i, j;
 
    for(j = 0; j < 4; j++){
        b[0][j] = mul(25,a[0][j]) ^ mul(1,a[1][j]) ^ a[2][j] ^ a[3][j];
        b[1][j] = mul(25,a[1][j]) ^ mul(1,a[2][j]) ^ a[3][j] ^ a[0][j];
        b[2][j] = mul(25,a[2][j]) ^ mul(1,a[3][j]) ^ a[0][j] ^ a[1][j];
        b[3][j] = mul(25,a[3][j]) ^ mul(1,a[0][j]) ^ a[1][j] ^ a[2][j];
    }
    for(i = 0; i < 4; i++)
        /*for(j = 0; j < BC; j++) a[i][j] = b[i][j];*/
        ((MV_U32*)(&(a[i][0])))[0] = ((MV_U32*)(&(b[i][0])))[0] ^ ((MV_U32*)(&(rk[i][0])))[0];
}

Referenced by rijndaelEncrypt128().

mul1()

MV_U8 mul1	(	MV_U8	aa,
		MV_U8	bb
	)

Definition at line 27 of file mvAesAlg.c.

{
    return mask[bb] & Alogtable[aa + Logtable[bb]];
}

rijndaelDecrypt128()

int rijndaelDecrypt128	(	MV_U8	a[4][MAXBC],
		MV_U8	rk[MAXROUNDS+1][4][MAXBC],
		int	rounds
	)

Definition at line 277 of file mvAesAlg.c.

{
    int r, BC, ROUNDS;
 
    BC = 4;
    ROUNDS = rounds;
 
    /* To decrypt: apply the inverse operations of the encrypt routine,
     *             in opposite order
     *
     * (KeyAddition is an involution: it 's equal to its inverse)
     * (the inverse of Substitution with table S is Substitution with the inverse table of S)
     * (the inverse of Shiftrow is Shiftrow over a suitable distance)
     */
 
        /* First the special round:
     *   without InvMixColumn
     *   with extra KeyAddition
     */
    KeyAddition(a,rk[ROUNDS],BC);
    ShiftRow128Dec(a);
    Substitution(a,Si);
 
    /* ROUNDS-1 ordinary rounds
     */
    for(r = ROUNDS-1; r > 0; r--) {
        KeyAddition(a,rk[r],BC);
        InvMixColumn(a);
        ShiftRow128Dec(a);
        Substitution(a,Si);
 
    }
 
    /* End with the extra key addition
     */
 
    KeyAddition(a,rk[0],BC);
 
    return 0;
}

rijndaelEncrypt128()

int rijndaelEncrypt128	(	MV_U8	a[4][MAXBC],
		MV_U8	rk[MAXROUNDS+1][4][MAXBC],
		int	rounds
	)

Definition at line 244 of file mvAesAlg.c.

{
    /* Encryption of one block.
     */
    int r, BC, ROUNDS;
 
    BC = 4;
    ROUNDS = rounds;
 
    /* begin with a key addition
     */
 
    KeyAddition(a,rk[0],BC);
 
    /* ROUNDS-1 ordinary rounds
     */
    for(r = 1; r < ROUNDS; r++) {
        Substitution(a,S);
        ShiftRow128Enc(a);
        MixColumn(a, rk[r]);
        /*KeyAddition(a,rk[r],BC);*/
    }
 
    /* Last round is special: there is no MixColumn
     */
    Substitution(a,S);
    ShiftRow128Enc(a);
    KeyAddition(a,rk[ROUNDS],BC);
 
    return 0;
}

rijndaelKeySched()

int rijndaelKeySched	(	MV_U8	k[4][MAXKC],
		int	keyBits,
		int	blockBits,
		MV_U8	W[MAXROUNDS+1][4][MAXBC]
	)

Definition at line 179 of file mvAesAlg.c.

{
    /* Calculate the necessary round keys
     * The number of calculations depends on keyBits and blockBits
     */
    int KC, BC, ROUNDS;
    int i, j, t, rconpointer = 0;
    MV_U8 tk[4][MAXKC];
 
    switch (keyBits) {
    case 128: KC = 4; break;
    case 192: KC = 6; break;
    case 256: KC = 8; break;
    default : return (-1);
    }
 
    switch (blockBits) {
    case 128: BC = 4; break;
    case 192: BC = 6; break;
    case 256: BC = 8; break;
    default : return (-2);
    }
 
    switch (keyBits >= blockBits ? keyBits : blockBits) {
    case 128: ROUNDS = 10; break;
    case 192: ROUNDS = 12; break;
    case 256: ROUNDS = 14; break;
    default : return (-3); /* this cannot happen */
    }
 
 
    for(j = 0; j < KC; j++)
        for(i = 0; i < 4; i++)
            tk[i][j] = k[i][j];
    t = 0;
    /* copy values into round key array */
    for(j = 0; (j < KC) && (t < (ROUNDS+1)*BC); j++, t++)
        for(i = 0; i < 4; i++) W[t / BC][i][t % BC] = tk[i][j];
 
    while (t < (ROUNDS+1)*BC) { /* while not enough round key material calculated */
        /* calculate new values */
        for(i = 0; i < 4; i++)
            tk[i][0] ^= S[tk[(i+1)%4][KC-1]];
        tk[0][0] ^= rcon[rconpointer++];
 
        if (KC != 8)
            for(j = 1; j < KC; j++)
                for(i = 0; i < 4; i++) tk[i][j] ^= tk[i][j-1];
        else {
            for(j = 1; j < KC/2; j++)
                for(i = 0; i < 4; i++) tk[i][j] ^= tk[i][j-1];
            for(i = 0; i < 4; i++) tk[i][KC/2] ^= S[tk[i][KC/2 - 1]];
            for(j = KC/2 + 1; j < KC; j++)
                for(i = 0; i < 4; i++) tk[i][j] ^= tk[i][j-1];
    }
    /* copy values into round key array */
    for(j = 0; (j < KC) && (t < (ROUNDS+1)*BC); j++, t++)
        for(i = 0; i < 4; i++) W[t / BC][i][t % BC] = tk[i][j];
    }
 
    return 0;
}

ShiftRow128Dec()

void ShiftRow128Dec

(

MV_U8

a[4][MAXBC]

)

Definition at line 88 of file mvAesAlg.c.

                                       {
    /* Row 0 remains unchanged
     * The other three rows are shifted a variable amount
     */
    MV_U8 tmp[MAXBC];
 
    tmp[0] = a[1][3];
    tmp[1] = a[1][0];
    tmp[2] = a[1][1];
    tmp[3] = a[1][2];
 
    ((MV_U32*)(&(a[1][0])))[0] = ((MV_U32*)(&(tmp[0])))[0];
    /*
    a[1][0] = tmp[0];
    a[1][1] = tmp[1];
    a[1][2] = tmp[2];
    a[1][3] = tmp[3];
    */
 
    tmp[0] = a[2][2];
    tmp[1] = a[2][3];
    tmp[2] = a[2][0];
    tmp[3] = a[2][1];
 
    ((MV_U32*)(&(a[2][0])))[0] = ((MV_U32*)(&(tmp[0])))[0];
    /*
    a[2][0] = tmp[0];
    a[2][1] = tmp[1];
    a[2][2] = tmp[2];
    a[2][3] = tmp[3];
    */
 
    tmp[0] = a[3][1];
    tmp[1] = a[3][2];
    tmp[2] = a[3][3];
    tmp[3] = a[3][0];
 
    ((MV_U32*)(&(a[3][0])))[0] = ((MV_U32*)(&(tmp[0])))[0];
    /*
    a[3][0] = tmp[0];
    a[3][1] = tmp[1];
    a[3][2] = tmp[2];
    a[3][3] = tmp[3];
    */
}

Referenced by rijndaelDecrypt128().

ShiftRow128Enc()

void ShiftRow128Enc

(

MV_U8

a[4][MAXBC]

)

Definition at line 44 of file mvAesAlg.c.

                                       {
    /* Row 0 remains unchanged
     * The other three rows are shifted a variable amount
     */
    MV_U8 tmp[MAXBC];
 
    tmp[0] = a[1][1];
    tmp[1] = a[1][2];
    tmp[2] = a[1][3];
    tmp[3] = a[1][0];
 
    ((MV_U32*)(&(a[1][0])))[0] = ((MV_U32*)(&(tmp[0])))[0];
     /*
    a[1][0] = tmp[0];
    a[1][1] = tmp[1];
    a[1][2] = tmp[2];
    a[1][3] = tmp[3];
       */
    tmp[0] = a[2][2];
    tmp[1] = a[2][3];
    tmp[2] = a[2][0];
    tmp[3] = a[2][1];
 
    ((MV_U32*)(&(a[2][0])))[0] = ((MV_U32*)(&(tmp[0])))[0];
      /*
    a[2][0] = tmp[0];
    a[2][1] = tmp[1];
    a[2][2] = tmp[2];
    a[2][3] = tmp[3];
    */
    tmp[0] = a[3][3];
    tmp[1] = a[3][0];
    tmp[2] = a[3][1];
    tmp[3] = a[3][2];
 
    ((MV_U32*)(&(a[3][0])))[0] = ((MV_U32*)(&(tmp[0])))[0];
    /*
    a[3][0] = tmp[0];
    a[3][1] = tmp[1];
    a[3][2] = tmp[2];
    a[3][3] = tmp[3];
    */
}

Referenced by rijndaelEncrypt128().

Substitution()

void Substitution	(	MV_U8	a[4][MAXBC],
		MV_U8	box[256]
	)

Definition at line 134 of file mvAesAlg.c.

                                                     {
    /* Replace every byte of the input by the byte at that place
     * in the nonlinear S-box
     */
    int i, j;
 
    for(i = 0; i < 4; i++)
        for(j = 0; j < 4; j++) a[i][j] = box[a[i][j]] ;
}

Referenced by rijndaelDecrypt128(), and rijndaelEncrypt128().