package Digest::SHA; require 5.003000; use strict; use warnings; use vars qw($VERSION @ISA @EXPORT_OK $errmsg); use Fcntl qw(O_RDONLY O_RDWR); use integer; $VERSION = '6.02'; require Exporter; @ISA = qw(Exporter); @EXPORT_OK = qw( $errmsg hmac_sha1 hmac_sha1_base64 hmac_sha1_hex hmac_sha224 hmac_sha224_base64 hmac_sha224_hex hmac_sha256 hmac_sha256_base64 hmac_sha256_hex hmac_sha384 hmac_sha384_base64 hmac_sha384_hex hmac_sha512 hmac_sha512_base64 hmac_sha512_hex hmac_sha512224 hmac_sha512224_base64 hmac_sha512224_hex hmac_sha512256 hmac_sha512256_base64 hmac_sha512256_hex sha1 sha1_base64 sha1_hex sha224 sha224_base64 sha224_hex sha256 sha256_base64 sha256_hex sha384 sha384_base64 sha384_hex sha512 sha512_base64 sha512_hex sha512224 sha512224_base64 sha512224_hex sha512256 sha512256_base64 sha512256_hex); # Inherit from Digest::base if possible eval { require Digest::base; push(@ISA, 'Digest::base'); }; # The following routines aren't time-critical, so they can be left in Perl sub new { my($class, $alg) = @_; $alg =~ s/\D+//g if defined $alg; if (ref($class)) { # instance method if (!defined($alg) || ($alg == $class->algorithm)) { sharewind($class); return($class); } return shainit($class, $alg) ? $class : undef; } $alg = 1 unless defined $alg; return $class->newSHA($alg); } BEGIN { *reset = \&new } sub add_bits { my($self, $data, $nbits) = @_; unless (defined $nbits) { $nbits = length($data); $data = pack("B*", $data); } $nbits = length($data) * 8 if $nbits > length($data) * 8; shawrite($data, $nbits, $self); return($self); } sub _bail { my $msg = shift; $errmsg = $!; $msg .= ": $!"; require Carp; Carp::croak($msg); } { my $_can_T_filehandle; sub _istext { local *FH = shift; my $file = shift; if (! defined $_can_T_filehandle) { local $^W = 0; my $istext = eval { -T FH }; $_can_T_filehandle = $@ ? 0 : 1; return $_can_T_filehandle ? $istext : -T $file; } return $_can_T_filehandle ? -T FH : -T $file; } } sub _addfile { my ($self, $handle) = @_; my $n; my $buf = ""; while (($n = read($handle, $buf, 4096))) { $self->add($buf); } _bail("Read failed") unless defined $n; $self; } sub addfile { my ($self, $file, $mode) = @_; return(_addfile($self, $file)) unless ref(\$file) eq 'SCALAR'; $mode = defined($mode) ? $mode : ""; my ($binary, $UNIVERSAL, $BITS) = map { $_ eq $mode } ("b", "U", "0"); ## Always interpret "-" to mean STDIN; otherwise use ## sysopen to handle full range of POSIX file names. ## If $file is a directory, force an EISDIR error ## by attempting to open with mode O_RDWR local *FH; $file eq '-' and open(FH, '< -') or sysopen(FH, $file, -d $file ? O_RDWR : O_RDONLY) or _bail('Open failed'); if ($BITS) { my ($n, $buf) = (0, ""); while (($n = read(FH, $buf, 4096))) { $buf =~ tr/01//cd; $self->add_bits($buf); } _bail("Read failed") unless defined $n; close(FH); return($self); } binmode(FH) if $binary || $UNIVERSAL; if ($UNIVERSAL && _istext(*FH, $file)) { $self->_addfileuniv(*FH); } else { $self->_addfilebin(*FH) } close(FH); $self; } sub getstate { my $self = shift; my $alg = $self->algorithm or return; my $state = $self->_getstate or return; my $nD = $alg <= 256 ? 8 : 16; my $nH = $alg <= 256 ? 32 : 64; my $nB = $alg <= 256 ? 64 : 128; my($H, $block, $blockcnt, $lenhh, $lenhl, $lenlh, $lenll) = $state =~ /^(.{$nH})(.{$nB})(.{4})(.{4})(.{4})(.{4})(.{4})$/s; for ($alg, $H, $block, $blockcnt, $lenhh, $lenhl, $lenlh, $lenll) { return unless defined $_; } my @s = (); push(@s, "alg:" . $alg); push(@s, "H:" . join(":", unpack("H*", $H) =~ /.{$nD}/g)); push(@s, "block:" . join(":", unpack("H*", $block) =~ /.{2}/g)); push(@s, "blockcnt:" . unpack("N", $blockcnt)); push(@s, "lenhh:" . unpack("N", $lenhh)); push(@s, "lenhl:" . unpack("N", $lenhl)); push(@s, "lenlh:" . unpack("N", $lenlh)); push(@s, "lenll:" . unpack("N", $lenll)); join("\n", @s) . "\n"; } sub putstate { my($class, $state) = @_; my %s = (); for (split(/\n/, $state)) { s/^\s+//; s/\s+$//; next if (/^(#|$)/); my @f = split(/[:\s]+/); my $tag = shift(@f); $s{$tag} = join('', @f); } # H and block may contain arbitrary values, but check everything else grep { $_ == $s{'alg'} } (1,224,256,384,512,512224,512256) or return; length($s{'H'}) == ($s{'alg'} <= 256 ? 64 : 128) or return; length($s{'block'}) == ($s{'alg'} <= 256 ? 128 : 256) or return; { no integer; for (qw(blockcnt lenhh lenhl lenlh lenll)) { 0 <= $s{$_} or return; $s{$_} <= 4294967295 or return; } $s{'blockcnt'} < ($s{'alg'} <= 256 ? 512 : 1024) or return; } my $packed_state = ( pack("H*", $s{'H'}) . pack("H*", $s{'block'}) . pack("N", $s{'blockcnt'}) . pack("N", $s{'lenhh'}) . pack("N", $s{'lenhl'}) . pack("N", $s{'lenlh'}) . pack("N", $s{'lenll'}) ); return $class->new($s{'alg'})->_putstate($packed_state); } sub dump { my $self = shift; my $file = shift; my $state = $self->getstate or return; $file = "-" if (!defined($file) || $file eq ""); local *FH; open(FH, "> $file") or return; print FH $state; close(FH); return($self); } sub load { my $class = shift; my $file = shift; $file = "-" if (!defined($file) || $file eq ""); local *FH; open(FH, "< $file") or return; my $str = join('', ); close(FH); $class->putstate($str); } eval { require XSLoader; XSLoader::load('Digest::SHA', $VERSION); 1; } or do { require DynaLoader; push @ISA, 'DynaLoader'; Digest::SHA->bootstrap($VERSION); }; 1; __END__ =head1 NAME Digest::SHA - Perl extension for SHA-1/224/256/384/512 =head1 SYNOPSIS In programs: # Functional interface use Digest::SHA qw(sha1 sha1_hex sha1_base64 ...); $digest = sha1($data); $digest = sha1_hex($data); $digest = sha1_base64($data); $digest = sha256($data); $digest = sha384_hex($data); $digest = sha512_base64($data); # Object-oriented use Digest::SHA; $sha = Digest::SHA->new($alg); $sha->add($data); # feed data into stream $sha->addfile(*F); $sha->addfile($filename); $sha->add_bits($bits); $sha->add_bits($data, $nbits); $sha_copy = $sha->clone; # make copy of digest object $state = $sha->getstate; # save current state to string $sha->putstate($state); # restore previous $state $digest = $sha->digest; # compute digest $digest = $sha->hexdigest; $digest = $sha->b64digest; From the command line: $ shasum files $ shasum --help =head1 SYNOPSIS (HMAC-SHA) # Functional interface only use Digest::SHA qw(hmac_sha1 hmac_sha1_hex ...); $digest = hmac_sha1($data, $key); $digest = hmac_sha224_hex($data, $key); $digest = hmac_sha256_base64($data, $key); =head1 ABSTRACT Digest::SHA is a complete implementation of the NIST Secure Hash Standard. It gives Perl programmers a convenient way to calculate SHA-1, SHA-224, SHA-256, SHA-384, SHA-512, SHA-512/224, and SHA-512/256 message digests. The module can handle all types of input, including partial-byte data. =head1 DESCRIPTION Digest::SHA is written in C for speed. If your platform lacks a C compiler, you can install the functionally equivalent (but much slower) L module. The programming interface is easy to use: it's the same one found in CPAN's L module. So, if your applications currently use L and you'd prefer the stronger security of SHA, it's a simple matter to convert them. The interface provides two ways to calculate digests: all-at-once, or in stages. To illustrate, the following short program computes the SHA-256 digest of "hello world" using each approach: use Digest::SHA qw(sha256_hex); $data = "hello world"; @frags = split(//, $data); # all-at-once (Functional style) $digest1 = sha256_hex($data); # in-stages (OOP style) $state = Digest::SHA->new(256); for (@frags) { $state->add($_) } $digest2 = $state->hexdigest; print $digest1 eq $digest2 ? "whew!\n" : "oops!\n"; To calculate the digest of an n-bit message where I is not a multiple of 8, use the I method. For example, consider the 446-bit message consisting of the bit-string "110" repeated 148 times, followed by "11". Here's how to display its SHA-1 digest: use Digest::SHA; $bits = "110" x 148 . "11"; $sha = Digest::SHA->new(1)->add_bits($bits); print $sha->hexdigest, "\n"; Note that for larger bit-strings, it's more efficient to use the two-argument version I, where I<$data> is in the customary packed binary format used for Perl strings. The module also lets you save intermediate SHA states to a string. The I method generates portable, human-readable text describing the current state of computation. You can subsequently restore that state with I to resume where the calculation left off. To see what a state description looks like, just run the following: use Digest::SHA; print Digest::SHA->new->add("Shaw" x 1962)->getstate; As an added convenience, the Digest::SHA module offers routines to calculate keyed hashes using the HMAC-SHA-1/224/256/384/512 algorithms. These services exist in functional form only, and mimic the style and behavior of the I, I, and I functions. # Test vector from draft-ietf-ipsec-ciph-sha-256-01.txt use Digest::SHA qw(hmac_sha256_hex); print hmac_sha256_hex("Hi There", chr(0x0b) x 32), "\n"; =head1 UNICODE AND SIDE EFFECTS Perl supports Unicode strings as of version 5.6. Such strings may contain wide characters, namely, characters whose ordinal values are greater than 255. This can cause problems for digest algorithms such as SHA that are specified to operate on sequences of bytes. The rule by which Digest::SHA handles a Unicode string is easy to state, but potentially confusing to grasp: the string is interpreted as a sequence of byte values, where each byte value is equal to the ordinal value (viz. code point) of its corresponding Unicode character. That way, the Unicode string 'abc' has exactly the same digest value as the ordinary string 'abc'. Since a wide character does not fit into a byte, the Digest::SHA routines croak if they encounter one. Whereas if a Unicode string contains no wide characters, the module accepts it quite happily. The following code illustrates the two cases: $str1 = pack('U*', (0..255)); print sha1_hex($str1); # ok $str2 = pack('U*', (0..256)); print sha1_hex($str2); # croaks Be aware that the digest routines silently convert UTF-8 input into its equivalent byte sequence in the native encoding (cf. utf8::downgrade). This side effect influences only the way Perl stores the data internally, but otherwise leaves the actual value of the data intact. =head1 NIST STATEMENT ON SHA-1 NIST acknowledges that the work of Prof. Xiaoyun Wang constitutes a practical collision attack on SHA-1. Therefore, NIST encourages the rapid adoption of the SHA-2 hash functions (e.g. SHA-256) for applications requiring strong collision resistance, such as digital signatures. ref. L =head1 PADDING OF BASE64 DIGESTS By convention, CPAN Digest modules do B pad their Base64 output. Problems can occur when feeding such digests to other software that expects properly padded Base64 encodings. For the time being, any necessary padding must be done by the user. Fortunately, this is a simple operation: if the length of a Base64-encoded digest isn't a multiple of 4, simply append "=" characters to the end of the digest until it is: while (length($b64_digest) % 4) { $b64_digest .= '='; } To illustrate, I is computed to be ungWv48Bz+pBQUDeXa4iI7ADYaOWF3qctBD/YfIAFa0 which has a length of 43. So, the properly padded version is ungWv48Bz+pBQUDeXa4iI7ADYaOWF3qctBD/YfIAFa0= =head1 EXPORT None by default. =head1 EXPORTABLE FUNCTIONS Provided your C compiler supports a 64-bit type (e.g. the I of C99, or I<__int64> used by Microsoft C/C++), all of these functions will be available for use. Otherwise, you won't be able to perform the SHA-384 and SHA-512 transforms, both of which require 64-bit operations. I =over 4 =item B =item B =item B =item B =item B =item B =item B Logically joins the arguments into a single string, and returns its SHA-1/224/256/384/512 digest encoded as a binary string. =item B =item B =item B =item B =item B =item B =item B Logically joins the arguments into a single string, and returns its SHA-1/224/256/384/512 digest encoded as a hexadecimal string. =item B =item B =item B =item B =item B =item B =item B Logically joins the arguments into a single string, and returns its SHA-1/224/256/384/512 digest encoded as a Base64 string. It's important to note that the resulting string does B contain the padding characters typical of Base64 encodings. This omission is deliberate, and is done to maintain compatibility with the family of CPAN Digest modules. See L for details. =back I =over 4 =item B Returns a new Digest::SHA object. Allowed values for I<$alg> are 1, 224, 256, 384, 512, 512224, or 512256. It's also possible to use common string representations of the algorithm (e.g. "sha256", "SHA-384"). If the argument is missing, SHA-1 will be used by default. Invoking I as an instance method will reset the object to the initial state associated with I<$alg>. If the argument is missing, the object will continue using the same algorithm that was selected at creation. =item B This method has exactly the same effect as I. In fact, I is just an alias for I. =item B Returns the number of digest bits for this object. The values are 160, 224, 256, 384, 512, 224, and 256 for SHA-1, SHA-224, SHA-256, SHA-384, SHA-512, SHA-512/224 and SHA-512/256, respectively. =item B Returns the digest algorithm for this object. The values are 1, 224, 256, 384, 512, 512224, and 512256 for SHA-1, SHA-224, SHA-256, SHA-384, SHA-512, SHA-512/224, and SHA-512/256, respectively. =item B Returns a duplicate copy of the object. =item B Logically joins the arguments into a single string, and uses it to update the current digest state. In other words, the following statements have the same effect: $sha->add("a"); $sha->add("b"); $sha->add("c"); $sha->add("a")->add("b")->add("c"); $sha->add("a", "b", "c"); $sha->add("abc"); The return value is the updated object itself. =item B =item B Updates the current digest state by appending bits to it. The return value is the updated object itself. The first form causes the most-significant I<$nbits> of I<$data> to be appended to the stream. The I<$data> argument is in the customary binary format used for Perl strings. The second form takes an ASCII string of "0" and "1" characters as its argument. It's equivalent to $sha->add_bits(pack("B*", $bits), length($bits)); So, the following two statements do the same thing: $sha->add_bits("111100001010"); $sha->add_bits("\xF0\xA0", 12); Note that SHA-1 and SHA-2 use I for their internal state. This means that $sha3->add_bits("110"); is equivalent to $sha3->add_bits("1")->add_bits("1")->add_bits("0"); =item B Reads from I until EOF, and appends that data to the current state. The return value is the updated object itself. =item B Reads the contents of I<$filename>, and appends that data to the current state. The return value is the updated object itself. By default, I<$filename> is simply opened and read; no special modes or I/O disciplines are used. To change this, set the optional I<$mode> argument to one of the following values: "b" read file in binary mode "U" use universal newlines "0" use BITS mode The "U" mode is modeled on Python's "Universal Newlines" concept, whereby DOS and Mac OS line terminators are converted internally to UNIX newlines before processing. This ensures consistent digest values when working simultaneously across multiple file systems. B, namely those passing Perl's I<-T> test; binary files are processed with no translation whatsoever. The BITS mode ("0") interprets the contents of I<$filename> as a logical stream of bits, where each ASCII '0' or '1' character represents a 0 or 1 bit, respectively. All other characters are ignored. This provides a convenient way to calculate the digest values of partial-byte data by using files, rather than having to write separate programs employing the I method. =item B Returns a string containing a portable, human-readable representation of the current SHA state. =item B Returns a Digest::SHA object representing the SHA state contained in I<$str>. The format of I<$str> matches the format of the output produced by method I. If called as a class method, a new object is created; if called as an instance method, the object is reset to the state contained in I<$str>. =item B Writes the output of I to I<$filename>. If the argument is missing, or equal to the empty string, the state information will be written to STDOUT. =item B Returns a Digest::SHA object that results from calling I on the contents of I<$filename>. If the argument is missing, or equal to the empty string, the state information will be read from STDIN. =item B Returns the digest encoded as a binary string. Note that the I method is a read-once operation. Once it has been performed, the Digest::SHA object is automatically reset in preparation for calculating another digest value. Call I<$sha-Eclone-Edigest> if it's necessary to preserve the original digest state. =item B Returns the digest encoded as a hexadecimal string. Like I, this method is a read-once operation. Call I<$sha-Eclone-Ehexdigest> if it's necessary to preserve the original digest state. =item B Returns the digest encoded as a Base64 string. Like I, this method is a read-once operation. Call I<$sha-Eclone-Eb64digest> if it's necessary to preserve the original digest state. It's important to note that the resulting string does B contain the padding characters typical of Base64 encodings. This omission is deliberate, and is done to maintain compatibility with the family of CPAN Digest modules. See L for details. =back I =over 4 =item B =item B =item B =item B =item B =item B =item B Returns the HMAC-SHA-1/224/256/384/512 digest of I<$data>/I<$key>, with the result encoded as a binary string. Multiple I<$data> arguments are allowed, provided that I<$key> is the last argument in the list. =item B =item B =item B =item B =item B =item B =item B Returns the HMAC-SHA-1/224/256/384/512 digest of I<$data>/I<$key>, with the result encoded as a hexadecimal string. Multiple I<$data> arguments are allowed, provided that I<$key> is the last argument in the list. =item B =item B =item B =item B =item B =item B =item B Returns the HMAC-SHA-1/224/256/384/512 digest of I<$data>/I<$key>, with the result encoded as a Base64 string. Multiple I<$data> arguments are allowed, provided that I<$key> is the last argument in the list. It's important to note that the resulting string does B contain the padding characters typical of Base64 encodings. This omission is deliberate, and is done to maintain compatibility with the family of CPAN Digest modules. See L for details. =back =head1 SEE ALSO L, L The Secure Hash Standard (Draft FIPS PUB 180-4) can be found at: L The Keyed-Hash Message Authentication Code (HMAC): L =head1 AUTHOR Mark Shelor =head1 ACKNOWLEDGMENTS The author is particularly grateful to Gisle Aas H. Merijn Brand Sean Burke Chris Carey Alexandr Ciornii Chris David Jim Doble Thomas Drugeon Julius Duque Jeffrey Friedl Robert Gilmour Brian Gladman Jarkko Hietaniemi Adam Kennedy Mark Lawrence Andy Lester Alex Muntada Steve Peters Chris Skiscim Martin Thurn Gunnar Wolf Adam Woodbury "who by trained skill rescued life from such great billows and such thick darkness and moored it in so perfect a calm and in so brilliant a light" - Lucretius =head1 COPYRIGHT AND LICENSE Copyright (C) 2003-2018 Mark Shelor This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself. L =cut