1Crypt::CipherSaber(3) User Contributed Perl DocumentationCrypt::CipherSaber(3)
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6 Crypt::CipherSaber - Perl module implementing CipherSaber encryption.
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9 use Crypt::CipherSaber;
10 my $cs = Crypt::CipherSaber->new('my pathetic secret key');
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12 my $coded = $cs->encrypt('Here is a secret message for you');
13 my $decoded = $cs->decrypt($coded);
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15 # encrypt from and to a file
16 open(INFILE, 'secretletter.txt') or die "Can't open infile: $!";
17 open(OUTFILE, '>secretletter.cs1') or die "Can't open outfile: $!";
18 binmode(INFILE);
19 binmode(OUTFILE);
20 $cs->fh_crypt(\*INFILE, \*OUTFILE, 1);
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22 # decrypt from and to a file
23 open(INFILE, 'secretletter.cs1') or die "Can't open infile: $!";
24 open(OUTFILE, '>secretletter.txt') or die "Can't open outfile: $!";
25 binmode(INFILE);
26 binmode(OUTFILE);
27 $cs->fh_crypt(\*INFILE, \*OUTFILE);
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30 The Crypt::CipherSaber module implements CipherSaber encryption,
31 described at <http://ciphersaber.gurus.com/>. It is simple, fairly
32 speedy, and relatively secure algorithm based on RC4.
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34 Encryption and decryption are done based on a secret key, which must be
35 shared with all intended recipients of a message.
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38 new($key, $N)
39 Initialize a new Crypt::CipherSaber object. $key is a required
40 parameter: the key used to encrypt or to decrypt messages. $N is
41 optional. If provided and greater than one, it causes the object
42 to use CipherSaber-2 encryption (slightly slower but more secure).
43 If not specified, or equal to 1, the module defaults to
44 CipherSaber-1 encryption. $N must be a positive integer greater
45 than one.
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47 encrypt($message)
48 Encrypt a message. This uses the key stored in the current
49 Crypt::CipherSaber object. It generates a 10-byte random IV
50 (Initialization Vector) automatically, as defined in the RC4
51 specification. This returns a string containing the encrypted
52 message.
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54 Note that the encrypted message may contain unprintable characters,
55 as it uses the extended ASCII character set (valid numbers 0
56 through 255).
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58 decrypt($message)
59 Decrypt a message. For the curious, the first ten bytes of an
60 encrypted message are the IV, so this must strip it off first.
61 This returns a string containing the decrypted message.
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63 The decrypted message may also contain unprintable characters, as
64 the CipherSaber encryption scheme handles binary filesIf this is
65 important to you, be sure to treat the results correctly.
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67 crypt($iv, $message)
68 If you wish to generate the IV with a more cryptographically secure
69 random string (at least compared to Perl's builtin "rand()"
70 operator), you may do so separately, passing it to this method
71 directly. The IV must be a ten-byte string consisting of
72 characters from the extended ASCII set.
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74 This is generally only useful for encryption, although you may
75 extract the first ten characters of an encrypted message and pass
76 them in yourself. You might as well call decrypt(), though. The
77 more random the IV, the stronger the encryption tends to be. On
78 some operating systems, you can read from /dev/random. Other
79 approaches are the Math::TrulyRandom module, or compressing a file,
80 removing the headers, and compressing it again.
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82 fh_crypt(\*INPUT, \*OUTPUT, ($iv))
83 For the sake of efficiency, Crypt::CipherSaber can filehandles.
84 It's not super brilliant, but it's relatively fast and sane. Pass
85 in a reference to the input file handle and the output filehandle.
86 If your platform needs to use "binmode()", this is your
87 responsibility. It is also your responsibility to close the files.
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89 You may also pass in an optional third parameter, an IV. There are
90 three possibilities here. If you pass no IV, "fh_crypt()" will
91 pull the first ten bytes from the input filehandle and use that as
92 an IV. This corresponds to decryption. If you pass in an IV of
93 your own, it will use that when encrypting the file. If you pass
94 in the value 1, it will generate a new, random IV for you. This
95 corresponds to an encryption.
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98 Copyright (C) 2000 - 2001, 2005 chromatic
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100 This library is free software; you can use, modify, and redistribute it
101 under the same terms as Perl 5.8.x itself.
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104 chromatic "chromatic at wgz dot org"
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106 thanks to jlp for testing, moral support, and never fearing the icky
107 details and to the fine folks at http://perlmonks.org/.
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109 Additional thanks to Olivier Salaun and the Sympa project
110 (http://www.sympa.org) for testing.
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113 the CipherSaber home page at <http://ciphersaber.gurus.com/>
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115 perl(1), rand().
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119perl v5.12.0 2010-04-30 Crypt::CipherSaber(3)