/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifdef FREEBL_NO_DEPEND

#include "stubs.h"

#endif

#include "prerr.h"

#include "secerr.h"

#include "prtypes.h"

#include "blapi.h"

#define MD2_DIGEST_LEN 16

#define MD2_BUFSIZE 16

#define MD2_X_SIZE 48  /* The X array, [CV | INPUT | TMP VARS] */

#define MD2_CV 0       /* index into X for chaining variables */

#define MD2_INPUT 16   /* index into X for input */

#define MD2_TMPVARS 32 /* index into X for temporary variables */

#define MD2_CHECKSUM_SIZE 16

struct MD2ContextStr {

    unsigned char checksum[MD2_BUFSIZE];

    unsigned char X[MD2_X_SIZE];

    PRUint8 unusedBuffer;

};

static const PRUint8 MD2S[256] = {

    0051, 0056, 0103, 0311, 0242, 0330, 0174, 0001,

    0075, 0066, 0124, 0241, 0354, 0360, 0006, 0023,

    0142, 0247, 0005, 0363, 0300, 0307, 0163, 0214,

    0230, 0223, 0053, 0331, 0274, 0114, 0202, 0312,

    0036, 0233, 0127, 0074, 0375, 0324, 0340, 0026,

    0147, 0102, 0157, 0030, 0212, 0027, 0345, 0022,

    0276, 0116, 0304, 0326, 0332, 0236, 0336, 0111,

    0240, 0373, 0365, 0216, 0273, 0057, 0356, 0172,

    0251, 0150, 0171, 0221, 0025, 0262, 0007, 0077,

    0224, 0302, 0020, 0211, 0013, 0042, 0137, 0041,

    0200, 0177, 0135, 0232, 0132, 0220, 0062, 0047,

    0065, 0076, 0314, 0347, 0277, 0367, 0227, 0003,

    0377, 0031, 0060, 0263, 0110, 0245, 0265, 0321,

    0327, 0136, 0222, 0052, 0254, 0126, 0252, 0306,

    0117, 0270, 0070, 0322, 0226, 0244, 0175, 0266,

    0166, 0374, 0153, 0342, 0234, 0164, 0004, 0361,

    0105, 0235, 0160, 0131, 0144, 0161, 0207, 0040,

    0206, 0133, 0317, 0145, 0346, 0055, 0250, 0002,

    0033, 0140, 0045, 0255, 0256, 0260, 0271, 0366,

    0034, 0106, 0141, 0151, 0064, 0100, 0176, 0017,

    0125, 0107, 0243, 0043, 0335, 0121, 0257, 0072,

    0303, 0134, 0371, 0316, 0272, 0305, 0352, 0046,

    0054, 0123, 0015, 0156, 0205, 0050, 0204, 0011,

    0323, 0337, 0315, 0364, 0101, 0201, 0115, 0122,

    0152, 0334, 0067, 0310, 0154, 0301, 0253, 0372,

    0044, 0341, 0173, 0010, 0014, 0275, 0261, 0112,

    0170, 0210, 0225, 0213, 0343, 0143, 0350, 0155,

    0351, 0313, 0325, 0376, 0073, 0000, 0035, 0071,

    0362, 0357, 0267, 0016, 0146, 0130, 0320, 0344,

    0246, 0167, 0162, 0370, 0353, 0165, 0113, 0012,

    0061, 0104, 0120, 0264, 0217, 0355, 0037, 0032,

    0333, 0231, 0215, 0063, 0237, 0021, 0203, 0024

};

SECStatus

MD2_Hash(unsigned char *dest, const char *src)

{

    unsigned int len;

    MD2Context *cx = MD2_NewContext();

    if (!cx) {

        PORT_SetError(PR_OUT_OF_MEMORY_ERROR);

        return SECFailure;

    }

    MD2_Begin(cx);

    MD2_Update(cx, (const unsigned char *)src, PORT_Strlen(src));

    MD2_End(cx, dest, &len, MD2_DIGEST_LEN);

    MD2_DestroyContext(cx, PR_TRUE);

    return SECSuccess;

}

MD2Context *

MD2_NewContext(void)

{

    MD2Context *cx = (MD2Context *)PORT_ZAlloc(sizeof(MD2Context));

    if (cx == NULL) {

        PORT_SetError(PR_OUT_OF_MEMORY_ERROR);

        return NULL;

    }

    return cx;

}

void

MD2_DestroyContext(MD2Context *cx, PRBool freeit)

{

    if (freeit)

        PORT_ZFree(cx, sizeof(*cx));

}

void

MD2_Begin(MD2Context *cx)

{

    memset(cx, 0, sizeof(*cx));

    cx->unusedBuffer = MD2_BUFSIZE;

}

static void

md2_compress(MD2Context *cx)

{

    int j;

    unsigned char P;

    P = cx->checksum[MD2_CHECKSUM_SIZE - 1];

/* Compute the running checksum, and set the tmp variables to be

 * CV[i] XOR input[i]

 */

#define CKSUMFN(n)                                        \

    P = cx->checksum[n] ^ MD2S[cx->X[MD2_INPUT + n] ^ P]; \

    cx->checksum[n] = P;                                  \

    cx->X[MD2_TMPVARS + n] = cx->X[n] ^ cx->X[MD2_INPUT + n];

    CKSUMFN(0);

    CKSUMFN(1);

    CKSUMFN(2);

    CKSUMFN(3);

    CKSUMFN(4);

    CKSUMFN(5);

    CKSUMFN(6);

    CKSUMFN(7);

    CKSUMFN(8);

    CKSUMFN(9);

    CKSUMFN(10);

    CKSUMFN(11);

    CKSUMFN(12);

    CKSUMFN(13);

    CKSUMFN(14);

    CKSUMFN(15);

/* The compression function. */

#define COMPRESS(n)         \

    P = cx->X[n] ^ MD2S[P]; \

    cx->X[n] = P;

    P = 0x00;

    for (j = 0; j < 18; j++) {

        COMPRESS(0);

        COMPRESS(1);

        COMPRESS(2);

        COMPRESS(3);

        COMPRESS(4);

        COMPRESS(5);

        COMPRESS(6);

        COMPRESS(7);

        COMPRESS(8);

        COMPRESS(9);

        COMPRESS(10);

        COMPRESS(11);

        COMPRESS(12);

        COMPRESS(13);

        COMPRESS(14);

        COMPRESS(15);

        COMPRESS(16);

        COMPRESS(17);

        COMPRESS(18);

        COMPRESS(19);

        COMPRESS(20);

        COMPRESS(21);

        COMPRESS(22);

        COMPRESS(23);

        COMPRESS(24);

        COMPRESS(25);

        COMPRESS(26);

        COMPRESS(27);

        COMPRESS(28);

        COMPRESS(29);

        COMPRESS(30);

        COMPRESS(31);

        COMPRESS(32);

        COMPRESS(33);

        COMPRESS(34);

        COMPRESS(35);

        COMPRESS(36);

        COMPRESS(37);

        COMPRESS(38);

        COMPRESS(39);

        COMPRESS(40);

        COMPRESS(41);

        COMPRESS(42);

        COMPRESS(43);

        COMPRESS(44);

        COMPRESS(45);

        COMPRESS(46);

        COMPRESS(47);

        P = (P + j) % 256;

    }

    cx->unusedBuffer = MD2_BUFSIZE;

}

void

MD2_Update(MD2Context *cx, const unsigned char *input, unsigned int inputLen)

{

    PRUint32 bytesToConsume;

    /* Reject corrupt deserialized state: unusedBuffer must never exceed

     * MD2_BUFSIZE, otherwise the index computation below underflows. */

    if (cx->unusedBuffer > MD2_BUFSIZE) {

        PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);

        return;

    }

    /* Fill the remaining input buffer. */

    if (cx->unusedBuffer != MD2_BUFSIZE) {

        bytesToConsume = PR_MIN(inputLen, cx->unusedBuffer);

        memcpy(&cx->X[MD2_INPUT + (MD2_BUFSIZE - cx->unusedBuffer)],

               input, bytesToConsume);

        if (cx->unusedBuffer + bytesToConsume >= MD2_BUFSIZE)

            md2_compress(cx);

        inputLen -= bytesToConsume;

        input += bytesToConsume;

    }

    /* Iterate over 16-byte chunks of the input. */

    while (inputLen >= MD2_BUFSIZE) {

        memcpy(&cx->X[MD2_INPUT], input, MD2_BUFSIZE);

        md2_compress(cx);

        inputLen -= MD2_BUFSIZE;

        input += MD2_BUFSIZE;

    }

    /* Copy any input that remains into the buffer. */

    if (inputLen)

        memcpy(&cx->X[MD2_INPUT], input, inputLen);

    cx->unusedBuffer = MD2_BUFSIZE - inputLen;

}

void

MD2_End(MD2Context *cx, unsigned char *digest,

        unsigned int *digestLen, unsigned int maxDigestLen)

{

    PRUint8 padStart;

    if (maxDigestLen < MD2_BUFSIZE) {

        PORT_SetError(SEC_ERROR_INVALID_ARGS);

        return;

    }

    /* Reject corrupt deserialized state: unusedBuffer must never exceed

     * MD2_BUFSIZE, otherwise padStart wraps and the memset below overflows. */

    if (cx->unusedBuffer > MD2_BUFSIZE) {

        PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);

        return;

    }

    padStart = MD2_BUFSIZE - cx->unusedBuffer;

    memset(&cx->X[MD2_INPUT + padStart], cx->unusedBuffer,

           cx->unusedBuffer);

    md2_compress(cx);

    memcpy(&cx->X[MD2_INPUT], cx->checksum, MD2_BUFSIZE);

    md2_compress(cx);

    *digestLen = MD2_DIGEST_LEN;

    memcpy(digest, &cx->X[MD2_CV], MD2_DIGEST_LEN);

}

unsigned int

MD2_FlattenSize(MD2Context *cx)

{

    return sizeof(*cx);

}

SECStatus

MD2_Flatten(MD2Context *cx, unsigned char *space)

{

    memcpy(space, cx, sizeof(*cx));

    return SECSuccess;

}

MD2Context *

MD2_Resurrect(unsigned char *space, void *arg)

{

    MD2Context *cx = MD2_NewContext();

    if (cx)

        memcpy(cx, space, sizeof(*cx));

    return cx;

}

void

MD2_Clone(MD2Context *dest, MD2Context *src)

{

    memcpy(dest, src, sizeof *dest);

}