dlock.c

DIAMOND2加密算法的原代码

                }
            }
        else
            {
            lite_encrypt_block(plaintext, seed);
            for (i=0; i<blocksize; i++)
                {
                if (seed[i] != ciphertext[i])
                    {
                    puts("Encryption error.");
                    exit(8);
                    }
                }
            lite_decrypt_block(ciphertext, seed);
            for (i=0; i<blocksize; i++)
                {
                if (seed[i] != plaintext[i])
                    {
                    puts("Decryption error.");
                    exit(8);
                    }
                }
            }
        }
    fclose(f);
    }

static void get_pass_phrase(char *key, uint maxlength)
    {
    int ch;
    uint keypos;

    puts("Please enter your pass phrase (case sensitive):");
    keypos = 0;
    key[0] = 0;
    do
        {
#ifdef UNIX
        ch = getchar();
#else
        ch = getch();
        if (!ch) ch = 0x100 + getch();
#endif
        if (((ch == 8) || (ch == 127)) && keypos)
            {
            key[--keypos] = 0;
            printf("\x08 \x08");
            }
        else if ((ch == 27) || (ch == 3))
            {
            key[0] = 0;
            }
        else if ((ch != 13) && (ch != 10) && (ch != 8) && (ch != 127))
            {
            printf("*");
            key[keypos++] = (char) ch;
            key[keypos] = 0;
            }
        }
    while ((ch != 13) && (ch != 10) && (ch != 3) && (ch != 27) && (keypos < (maxlength-1)));
    puts("\r                                                                              "); 
    }

void help(void)
    {
    puts("\nCopyright (C) 1994 Michael Paul Johnson.\n"
        "All rights reserved.  No warranty.\n\n"
        "To test Diamond and Diamond Lite against validation data:\n"
        "  DLOCK /T\n"
#ifdef MPJs_Copy
        "To generate new validation data set:\n"
        "  DLOCK /G\n"
#endif
        "To encrypt a file:\n"
        "  DLOCK /E [/S] infilename outfilename [/Ppass phrase | /Kkeyfile]\n"
        "To decrypt a file:\n"
        "  DLOCK /D [/S] infilename outfilename [/Ppass phrase | /Kkeyfile]\n"
        "/S = Silent mode (minimal screen output).\n");
    exit(1);
    }

int encrypt_file(char *inname, char *outname, uint keysize, byte *key)
    {
    int infile, outfile, bytesinbuf, i, blockpos;
    byte *buf;
    byte lastciphertext[16];
    ulong bytesdone;

    buf = (byte*) malloc(CHUNK);
    if (!buf)
        {
        puts("Out of memory.");
        return(3);
        }
    infile = open(inname, O_RDONLY | O_BINARY);
    if (infile < 0)
        {
        printf("Can't open %s\n", inname);
        return(13);
        }
    outfile = open(outname,O_WRONLY|O_EXCL|O_CREAT|O_BINARY,S_IREAD|S_IWRITE);
    if (outfile < 0)
        {
        printf("Can't open %s\n", outname);
        puts("Output file cannot already exist.");
        return(14);
        }
    bytesdone = 0;
    set_diamond_key(key, keysize, 10, false, 16);
    memset(lastciphertext, 0, 16);
    diamond_encrypt_block(lastciphertext, lastciphertext);
    blockpos = 0;
    do
        {
        bytesinbuf = read(infile, (char *)buf, CHUNK);
        for (i = 0; i<bytesinbuf; i++)
            {
            buf[i] ^= lastciphertext[blockpos++];
            if (blockpos >= 16)
                {
                blockpos = 0;
                diamond_encrypt_block(buf + i - 15, lastciphertext);
                }
            }
        if (bytesinbuf)
            {
            if (write(outfile, (char *)buf, bytesinbuf) != bytesinbuf)
                {
                printf("Error writing to %s\n", outname);
                return(15);
                }
            bytesdone += bytesinbuf;
            if (verbose) printf("\r%lu bytes encrypted.  ", bytesdone);
            }
        }
    while (bytesinbuf == CHUNK);
    if (close(outfile)) printf("Error closing %s\n", outname);
    close(infile);
    diamond_done();
    if (verbose) puts("");
    return 0;
    }

int decrypt_file(char *inname, char *outname, uint keysize, byte *key)
    {
    int infile, outfile, bytesinbuf, i, blockpos;
    byte *buf;
    byte lastciphertext[16];
    byte thisciphertext[16];
    ulong bytesdone;

    buf = (byte*) malloc(CHUNK);
    if (!buf)
        {
        puts("Out of memory.");
        return(3);
        }
    infile = open(inname, O_RDONLY | O_BINARY);
    if (infile < 0)
        {
        printf("Can't open %s\n", inname);
        return(13);
        }
    outfile = open(outname,O_WRONLY|O_EXCL|O_CREAT|O_BINARY,S_IREAD|S_IWRITE);
    if (outfile < 0)
        {
        printf("Can't open %s\n", outname);
        puts("Output file cannot already exist.");
        return(14);
        }
    bytesdone = 0;
    set_diamond_key(key, keysize, 10, false, 16);
    memset(lastciphertext, 0, 16);
    diamond_encrypt_block(lastciphertext, lastciphertext);
    blockpos = 0;
    do
        {
        bytesinbuf = read(infile, (char *)buf, CHUNK);
        for (i = 0; i<bytesinbuf; i++)
            {
            thisciphertext[blockpos] = buf[i];
            buf[i] ^= lastciphertext[blockpos++];
            if (blockpos >= 16)
                {
                blockpos = 0;
                diamond_encrypt_block(thisciphertext, lastciphertext);
                }
            }
        if (bytesinbuf)
            {
            if (write(outfile, (char *)buf, bytesinbuf) != bytesinbuf)
                {
                printf("Error writing to %s\n", outname);
                return(15);
                }
            bytesdone += bytesinbuf;
            printf("\r%lu bytes decrypted.  ", bytesdone);
            }
        }
    while (bytesinbuf == CHUNK);
    if (close(outfile)) printf("Error closing %s\n", outname);
    close(infile);
    diamond_done();
    if (verbose) puts("");
    return 0;
    }

int main(int argc, char** argv)
    {
    int i, c, keyfile;
    uint keysize;
    char *p;
    char keyfilename[PATHSIZE];

    generate = validate_file = startpass = encryptit = decryptit = false;
    verbose = true;
    keysize = 0;
    keyfilename[0] = 0;
    passphrase[0] = 0;

    for (i=1;i<argc;i++)
        {
        if ((!startpass) && (argv[i][0] == '-') || (argv[i][0] == '/'))
            {
            c = argv[i][1] | 0x20;
            switch (c)
                {
                case 'd':
                    decryptit = true;
                    encryptit = false;
                    break;
                case 'e':
                    decryptit = false;
                    encryptit = true;
                    break;
#ifdef MPJs_Copy
                case 'g':
                    generate = true;
                    break;
#endif
                case 'k':
                    strcpy(keyfilename, argv[i] + 2);
                    break;
                case 'p':
                    startpass = true;
                    strcpy((char *) passphrase, argv[i] + 2);
                    keysize = strlen((char *)passphrase);
                    break;
                case 's':
                    verbose = false;
                    break;
                case 't':
                    validate_file = true;
                    break;
                default:
                    help();
                    break;
                }
            }
        else if (startpass)
            {
            strcat((char *) passphrase, " ");
            strcat((char *) passphrase, argv[i]);
            keysize = strlen((char *)passphrase);
            }
        else if (infilename[0] == 0)
            {
            strcpy(infilename, argv[i]);
            }
        else if (outfilename[0] == 0)
            {
            strcpy(outfilename, argv[i]);
            }
        else
            {
            help();
            }
        }
    if (!(generate || validate_file || encryptit || decryptit))
        help();
#ifdef MPJs_Copy
    if (generate) generate_test_data();
#endif
    if (generate || validate_file) validate_test_data();
    if (encryptit || decryptit)
        {
        if (!outfilename[0])
            help();
        if (keysize)
            {
            if (verbose)
                puts("Using pass phrase from command line.");
            }
        else if (keyfilename[0])
            {
            keyfile = open(keyfilename, O_RDONLY|O_BINARY);
            if (keyfile >= 0)
                {
                keysize = read(keyfile, (char *)passphrase, PASS_SIZE);
                close(keyfile);
                if (verbose)
                    {
                    if (keysize)
                        printf("Using pass phrase from %s\n", keyfilename);
                    else
                        printf("No key read from file %s\n", keyfilename);
                    }
                }
            else
                {
                printf("Can't open %s\n", keyfilename);
                }
            }
        if (!keysize)
            {
            p = getenv("DLOCK_KEY");
            if (p)
                {
                strcpy((char *) passphrase, p);
                keysize = strlen((char *)passphrase);
                if (verbose)
                    puts("Using pass phrase from DLOCK_KEY environment variable.");
                }
            else
                {
                get_pass_phrase((char *) passphrase, PASS_SIZE);
                keysize = strlen((char *)passphrase);
                }
            }
        if (!keysize)
            {
            puts("Pass phrase required to encrypt or decrypt.");
            return(10);
            }
        if (keysize < 8)
            {
            puts("WARNING: PASS PHRASE IS TOO SHORT FOR SECURITY!");
            }
        if (encryptit)
            {
            if (verbose)
                printf("Encrypting %s to %s\n", infilename, outfilename);
            return(encrypt_file(infilename, outfilename, keysize, passphrase));
            }
        else
            {
            if (verbose)
                printf("Decrypting %s to %s\n", infilename, outfilename);
            return(decrypt_file(infilename, outfilename, keysize, passphrase));
            }
        }
    return 0;
    }