Crypt::RSA::SS::PSS(3pm)

1Crypt::RSA::SS::PSS(3)User Contributed Perl DocumentationCrypt::RSA::SS::PSS(3)
2
3
4

NAME

6       Crypt::RSA::SS::PSS - Probabilistic Signature Scheme based on RSA.
7

SYNOPSIS

9           my $pss = new Crypt::RSA::SS::PSS;
10
11           my $signature = $pss->sign (
12                               Message => $message,
13                               Key     => $private,
14                           ) ⎪⎪ die $pss->errstr;
15
16           my $verify    = $pss->verify (
17                               Message   => $message,
18                               Key       => $key,
19                               Signature => $signature,
20                           ) ⎪⎪ die $pss->errstr;
21

DESCRIPTION

23       PSS (Probabilistic Signature Scheme) is a provably secure method of
24       creating digital signatures with RSA. "Provable" means that the diffi‐
25       culty of forging signatures can be directly related to inverting the
26       RSA function. "Probabilistic" alludes to the randomly generated salt
27       value included in the signature to enhance security. For more details
28       on PSS, see [4] & [13].
29

METHODS

31       new()
32
33       Constructor.
34
35       version()
36
37       Returns the version number of the module.
38
39       sign()
40
41       Computes a PSS signature on a message with the private key of the
42       signer.  In scalar context, sign() returns the computed signature. In
43       array context, it returns the signature and the random salt. The signa‐
44       ture can verified with verify() or verify_with_salt(). sign() takes a
45       hash argument with the following mandatory keys:
46
47       Message
48           Message to be signed, a string of arbitrary length.
49
50       Key Private key of the signer, a Crypt::RSA::Key::Private object.
51
52       verify()
53
54       Verifies a signature generated with sign(). The salt is recovered from
55       the signature and need not be passed. Returns a true value on success
56       and false on failure. $self->errstr is set to "Invalid signature." or
57       appropriate error on failure. verify() takes a hash argument with the
58       following mandatory keys:
59
60       Key Public key of the signer, a Crypt::RSA::Key::Public object.
61
62       Message
63           The original signed message, a string of arbitrary length.
64
65       Signature
66           Signature computed with sign(), a string.
67
68       Version
69           Version of the module that was used for creating the Signature.
70           This is an optional argument. When present, verify() will ensure
71           before proceeding that the installed version of the module can suc‐
72           cessfully verify the Signature.
73
74       verify_with_salt()
75
76       Verifies a signature given the salt. Takes the same arguments as ver‐
77       ify() in addition to Salt, which is a 20-byte string returned by sign()
78       in array context.
79

ERROR HANDLING

81       See ERROR HANDLING in Crypt::RSA(3) manpage.
82

BIBLIOGRAPHY

84       See BIBLIOGRAPHY in Crypt::RSA(3) manpage.
85

AUTHOR

87       Vipul Ved Prakash, <mail@vipul.net>
88