6 use vars qw($VERSION @ISA @EXPORT @EXPORT_OK);
14 @ISA = qw(Exporter DynaLoader);
16 hmac_sha1 hmac_sha1_base64 hmac_sha1_hex
17 hmac_sha224 hmac_sha224_base64 hmac_sha224_hex
18 hmac_sha256 hmac_sha256_base64 hmac_sha256_hex
19 hmac_sha384 hmac_sha384_base64 hmac_sha384_hex
20 hmac_sha512 hmac_sha512_base64 hmac_sha512_hex
21 hmac_sha512224 hmac_sha512224_base64 hmac_sha512224_hex
22 hmac_sha512256 hmac_sha512256_base64 hmac_sha512256_hex
23 sha1 sha1_base64 sha1_hex
24 sha224 sha224_base64 sha224_hex
25 sha256 sha256_base64 sha256_hex
26 sha384 sha384_base64 sha384_hex
27 sha512 sha512_base64 sha512_hex
28 sha512224 sha512224_base64 sha512224_hex
29 sha512256 sha512256_base64 sha512256_hex);
31 # If possible, inherit from Digest::base (which depends on MIME::Base64)
38 push(@ISA, 'Digest::base');
41 *hexdigest = \&Hexdigest;
42 *b64digest = \&B64digest;
45 # The following routines aren't time-critical, so they can be left in Perl
48 my($class, $alg) = @_;
49 $alg =~ s/\D+//g if defined $alg;
50 if (ref($class)) { # instance method
51 unless (defined($alg) && ($alg != $class->algorithm)) {
55 shaclose($$class) if $$class;
56 $$class = shaopen($alg) || return;
59 $alg = 1 unless defined $alg;
60 my $state = shaopen($alg) || return;
68 shaclose($$self) if $$self;
73 my $state = shadup($$self) || return;
75 bless($copy, ref($self));
82 my($self, $data, $nbits) = @_;
83 unless (defined $nbits) {
84 $nbits = length($data);
85 $data = pack("B*", $data);
87 shawrite($data, $nbits, $$self);
95 Carp::croak("$msg: $!");
98 sub _addfile { # this is "addfile" from Digest::base 1.00
99 my ($self, $handle) = @_;
104 while (($n = read($handle, $buf, 4096))) {
107 _bail("Read failed") unless defined $n;
113 my ($self, $file, $mode) = @_;
115 return(_addfile($self, $file)) unless ref(\$file) eq 'SCALAR';
117 $mode = defined($mode) ? $mode : "";
118 my ($binary, $portable) = map { $_ eq $mode } ("b", "p");
120 ## Always interpret "-" to mean STDIN; otherwise use
121 ## sysopen to handle full range of POSIX file names
123 $file eq '-' and open(FH, '< -')
124 or sysopen(FH, $file, O_RDONLY)
125 or _bail('Open failed');
126 binmode(FH) if $binary || $portable;
128 unless ($portable && -T $file) {
129 $self->_addfile(*FH);
135 my ($buf1, $buf2) = ("", "");
137 while (($n1 = read(FH, $buf1, 4096))) {
138 while (substr($buf1, -1) eq "\015") {
139 $n2 = read(FH, $buf2, 4096);
140 _bail("Read failed") unless defined $n2;
144 $buf1 =~ s/\015?\015\012/\012/g; # DOS/Windows
145 $buf1 =~ s/\015/\012/g; # early MacOS
148 _bail("Read failed") unless defined $n1;
156 my $file = shift || "";
158 shadump($file, $$self) || return;
164 my $file = shift || "";
165 if (ref($class)) { # instance method
166 shaclose($$class) if $$class;
167 $$class = shaload($file) || return;
170 my $state = shaload($file) || return;
172 bless($self, $class);
176 Digest::SHA->bootstrap($VERSION);
183 Digest::SHA - Perl extension for SHA-1/224/256/384/512
189 # Functional interface
191 use Digest::SHA qw(sha1 sha1_hex sha1_base64 ...);
193 $digest = sha1($data);
194 $digest = sha1_hex($data);
195 $digest = sha1_base64($data);
197 $digest = sha256($data);
198 $digest = sha384_hex($data);
199 $digest = sha512_base64($data);
205 $sha = Digest::SHA->new($alg);
207 $sha->add($data); # feed data into stream
210 $sha->addfile($filename);
212 $sha->add_bits($bits);
213 $sha->add_bits($data, $nbits);
215 $sha_copy = $sha->clone; # if needed, make copy of
216 $sha->dump($file); # current digest state,
217 $sha->load($file); # or save it on disk
219 $digest = $sha->digest; # compute digest
220 $digest = $sha->hexdigest;
221 $digest = $sha->b64digest;
223 From the command line:
229 =head1 SYNOPSIS (HMAC-SHA)
231 # Functional interface only
233 use Digest::SHA qw(hmac_sha1 hmac_sha1_hex ...);
235 $digest = hmac_sha1($data, $key);
236 $digest = hmac_sha224_hex($data, $key);
237 $digest = hmac_sha256_base64($data, $key);
241 Digest::SHA is a complete implementation of the NIST Secure Hash Standard.
242 It gives Perl programmers a convenient way to calculate SHA-1, SHA-224,
243 SHA-256, SHA-384, SHA-512, SHA-512/224, and SHA-512/256 message digests.
244 The module can handle all types of input, including partial-byte data.
248 Digest::SHA is written in C for speed. If your platform lacks a
249 C compiler, you can install the functionally equivalent (but much
250 slower) L<Digest::SHA::PurePerl> module.
252 The programming interface is easy to use: it's the same one found
253 in CPAN's L<Digest> module. So, if your applications currently
254 use L<Digest::MD5> and you'd prefer the stronger security of SHA,
255 it's a simple matter to convert them.
257 The interface provides two ways to calculate digests: all-at-once,
258 or in stages. To illustrate, the following short program computes
259 the SHA-256 digest of "hello world" using each approach:
261 use Digest::SHA qw(sha256_hex);
263 $data = "hello world";
264 @frags = split(//, $data);
266 # all-at-once (Functional style)
267 $digest1 = sha256_hex($data);
269 # in-stages (OOP style)
270 $state = Digest::SHA->new(256);
271 for (@frags) { $state->add($_) }
272 $digest2 = $state->hexdigest;
274 print $digest1 eq $digest2 ?
275 "whew!\n" : "oops!\n";
277 To calculate the digest of an n-bit message where I<n> is not a
278 multiple of 8, use the I<add_bits()> method. For example, consider
279 the 446-bit message consisting of the bit-string "110" repeated
280 148 times, followed by "11". Here's how to display its SHA-1
284 $bits = "110" x 148 . "11";
285 $sha = Digest::SHA->new(1)->add_bits($bits);
286 print $sha->hexdigest, "\n";
288 Note that for larger bit-strings, it's more efficient to use the
289 two-argument version I<add_bits($data, $nbits)>, where I<$data> is
290 in the customary packed binary format used for Perl strings.
292 The module also lets you save intermediate SHA states to disk, or
293 display them on standard output. The I<dump()> method generates
294 portable, human-readable text describing the current state of
295 computation. You can subsequently retrieve the file with I<load()>
296 to resume where the calculation left off.
298 To see what a state description looks like, just run the following:
301 Digest::SHA->new->add("Shaw" x 1962)->dump;
303 As an added convenience, the Digest::SHA module offers routines to
304 calculate keyed hashes using the HMAC-SHA-1/224/256/384/512
305 algorithms. These services exist in functional form only, and
306 mimic the style and behavior of the I<sha()>, I<sha_hex()>, and
307 I<sha_base64()> functions.
309 # Test vector from draft-ietf-ipsec-ciph-sha-256-01.txt
311 use Digest::SHA qw(hmac_sha256_hex);
312 print hmac_sha256_hex("Hi There", chr(0x0b) x 32), "\n";
314 =head1 NIST STATEMENT ON SHA-1
316 I<NIST was recently informed that researchers had discovered a way
317 to "break" the current Federal Information Processing Standard SHA-1
318 algorithm, which has been in effect since 1994. The researchers
319 have not yet published their complete results, so NIST has not
320 confirmed these findings. However, the researchers are a reputable
321 research team with expertise in this area.>
323 I<Due to advances in computing power, NIST already planned to phase
324 out SHA-1 in favor of the larger and stronger hash functions (SHA-224,
325 SHA-256, SHA-384 and SHA-512) by 2010. New developments should use
326 the larger and stronger hash functions.>
328 ref. L<http://www.csrc.nist.gov/pki/HashWorkshop/NIST%20Statement/Burr_Mar2005.html>
330 =head1 PADDING OF BASE64 DIGESTS
332 By convention, CPAN Digest modules do B<not> pad their Base64 output.
333 Problems can occur when feeding such digests to other software that
334 expects properly padded Base64 encodings.
336 For the time being, any necessary padding must be done by the user.
337 Fortunately, this is a simple operation: if the length of a Base64-encoded
338 digest isn't a multiple of 4, simply append "=" characters to the end
339 of the digest until it is:
341 while (length($b64_digest) % 4) {
345 To illustrate, I<sha256_base64("abc")> is computed to be
347 ungWv48Bz+pBQUDeXa4iI7ADYaOWF3qctBD/YfIAFa0
349 which has a length of 43. So, the properly padded version is
351 ungWv48Bz+pBQUDeXa4iI7ADYaOWF3qctBD/YfIAFa0=
357 =head1 EXPORTABLE FUNCTIONS
359 Provided your C compiler supports a 64-bit type (e.g. the I<long
360 long> of C99, or I<__int64> used by Microsoft C/C++), all of these
361 functions will be available for use. Otherwise, you won't be able
362 to perform the SHA-384 and SHA-512 transforms, both of which require
369 =item B<sha1($data, ...)>
371 =item B<sha224($data, ...)>
373 =item B<sha256($data, ...)>
375 =item B<sha384($data, ...)>
377 =item B<sha512($data, ...)>
379 =item B<sha512224($data, ...)>
381 =item B<sha512256($data, ...)>
383 Logically joins the arguments into a single string, and returns
384 its SHA-1/224/256/384/512 digest encoded as a binary string.
386 =item B<sha1_hex($data, ...)>
388 =item B<sha224_hex($data, ...)>
390 =item B<sha256_hex($data, ...)>
392 =item B<sha384_hex($data, ...)>
394 =item B<sha512_hex($data, ...)>
396 =item B<sha512224_hex($data, ...)>
398 =item B<sha512256_hex($data, ...)>
400 Logically joins the arguments into a single string, and returns
401 its SHA-1/224/256/384/512 digest encoded as a hexadecimal string.
403 =item B<sha1_base64($data, ...)>
405 =item B<sha224_base64($data, ...)>
407 =item B<sha256_base64($data, ...)>
409 =item B<sha384_base64($data, ...)>
411 =item B<sha512_base64($data, ...)>
413 =item B<sha512224_base64($data, ...)>
415 =item B<sha512256_base64($data, ...)>
417 Logically joins the arguments into a single string, and returns
418 its SHA-1/224/256/384/512 digest encoded as a Base64 string.
420 It's important to note that the resulting string does B<not> contain
421 the padding characters typical of Base64 encodings. This omission is
422 deliberate, and is done to maintain compatibility with the family of
423 CPAN Digest modules. See L</"PADDING OF BASE64 DIGESTS"> for details.
433 Returns a new Digest::SHA object. Allowed values for I<$alg> are 1,
434 224, 256, 384, 512, 512224, or 512256. It's also possible to use
435 common string representations of the algorithm (e.g. "sha256",
436 "SHA-384"). If the argument is missing, SHA-1 will be used by
439 Invoking I<new> as an instance method will not create a new object;
440 instead, it will simply reset the object to the initial state
441 associated with I<$alg>. If the argument is missing, the object
442 will continue using the same algorithm that was selected at creation.
446 This method has exactly the same effect as I<new($alg)>. In fact,
447 I<reset> is just an alias for I<new>.
451 Returns the number of digest bits for this object. The values are
452 160, 224, 256, 384, 512, 224, and 256 for SHA-1, SHA-224, SHA-256,
453 SHA-384, SHA-512, SHA-512/224 and SHA-512/256, respectively.
457 Returns the digest algorithm for this object. The values are 1,
458 224, 256, 384, 512, 512224, and 512256 for SHA-1, SHA-224, SHA-256,
459 SHA-384, SHA-512, SHA-512/224, and SHA-512/256, respectively.
463 Returns a duplicate copy of the object.
465 =item B<add($data, ...)>
467 Logically joins the arguments into a single string, and uses it to
468 update the current digest state. In other words, the following
469 statements have the same effect:
471 $sha->add("a"); $sha->add("b"); $sha->add("c");
472 $sha->add("a")->add("b")->add("c");
473 $sha->add("a", "b", "c");
476 The return value is the updated object itself.
478 =item B<add_bits($data, $nbits)>
480 =item B<add_bits($bits)>
482 Updates the current digest state by appending bits to it. The
483 return value is the updated object itself.
485 The first form causes the most-significant I<$nbits> of I<$data>
486 to be appended to the stream. The I<$data> argument is in the
487 customary binary format used for Perl strings.
489 The second form takes an ASCII string of "0" and "1" characters as
490 its argument. It's equivalent to
492 $sha->add_bits(pack("B*", $bits), length($bits));
494 So, the following two statements do the same thing:
496 $sha->add_bits("111100001010");
497 $sha->add_bits("\xF0\xA0", 12);
499 =item B<addfile(*FILE)>
501 Reads from I<FILE> until EOF, and appends that data to the current
502 state. The return value is the updated object itself.
504 =item B<addfile($filename [, $mode])>
506 Reads the contents of I<$filename>, and appends that data to the current
507 state. The return value is the updated object itself.
509 By default, I<$filename> is simply opened and read; no special modes
510 or I/O disciplines are used. To change this, set the optional I<$mode>
511 argument to one of the following values:
513 "b" read file in binary mode
515 "p" use portable mode
517 The "p" mode is handy since it ensures that the digest value of
518 I<$filename> will be the same when computed on different operating
519 systems. It accomplishes this by internally translating all newlines in
520 text files to UNIX format before calculating the digest. Binary files
521 are read in raw mode with no translation whatsoever.
523 For a fuller discussion of newline formats, refer to CPAN module
524 L<File::LocalizeNewlines>. Its "universal line separator" regex forms
525 the basis of I<addfile>'s portable mode processing.
527 =item B<dump($filename)>
529 Provides persistent storage of intermediate SHA states by writing
530 a portable, human-readable representation of the current state to
531 I<$filename>. If the argument is missing, or equal to the empty
532 string, the state information will be written to STDOUT.
534 =item B<load($filename)>
536 Returns a Digest::SHA object representing the intermediate SHA
537 state that was previously dumped to I<$filename>. If called as a
538 class method, a new object is created; if called as an instance
539 method, the object is reset to the state contained in I<$filename>.
540 If the argument is missing, or equal to the empty string, the state
541 information will be read from STDIN.
545 Returns the digest encoded as a binary string.
547 Note that the I<digest> method is a read-once operation. Once it
548 has been performed, the Digest::SHA object is automatically reset
549 in preparation for calculating another digest value. Call
550 I<$sha-E<gt>clone-E<gt>digest> if it's necessary to preserve the
551 original digest state.
555 Returns the digest encoded as a hexadecimal string.
557 Like I<digest>, this method is a read-once operation. Call
558 I<$sha-E<gt>clone-E<gt>hexdigest> if it's necessary to preserve
559 the original digest state.
561 This method is inherited if L<Digest::base> is installed on your
562 system. Otherwise, a functionally equivalent substitute is used.
566 Returns the digest encoded as a Base64 string.
568 Like I<digest>, this method is a read-once operation. Call
569 I<$sha-E<gt>clone-E<gt>b64digest> if it's necessary to preserve
570 the original digest state.
572 This method is inherited if L<Digest::base> is installed on your
573 system. Otherwise, a functionally equivalent substitute is used.
575 It's important to note that the resulting string does B<not> contain
576 the padding characters typical of Base64 encodings. This omission is
577 deliberate, and is done to maintain compatibility with the family of
578 CPAN Digest modules. See L</"PADDING OF BASE64 DIGESTS"> for details.
582 I<HMAC-SHA-1/224/256/384/512>
586 =item B<hmac_sha1($data, $key)>
588 =item B<hmac_sha224($data, $key)>
590 =item B<hmac_sha256($data, $key)>
592 =item B<hmac_sha384($data, $key)>
594 =item B<hmac_sha512($data, $key)>
596 =item B<hmac_sha512224($data, $key)>
598 =item B<hmac_sha512256($data, $key)>
600 Returns the HMAC-SHA-1/224/256/384/512 digest of I<$data>/I<$key>,
601 with the result encoded as a binary string. Multiple I<$data>
602 arguments are allowed, provided that I<$key> is the last argument
605 =item B<hmac_sha1_hex($data, $key)>
607 =item B<hmac_sha224_hex($data, $key)>
609 =item B<hmac_sha256_hex($data, $key)>
611 =item B<hmac_sha384_hex($data, $key)>
613 =item B<hmac_sha512_hex($data, $key)>
615 =item B<hmac_sha512224_hex($data, $key)>
617 =item B<hmac_sha512256_hex($data, $key)>
619 Returns the HMAC-SHA-1/224/256/384/512 digest of I<$data>/I<$key>,
620 with the result encoded as a hexadecimal string. Multiple I<$data>
621 arguments are allowed, provided that I<$key> is the last argument
624 =item B<hmac_sha1_base64($data, $key)>
626 =item B<hmac_sha224_base64($data, $key)>
628 =item B<hmac_sha256_base64($data, $key)>
630 =item B<hmac_sha384_base64($data, $key)>
632 =item B<hmac_sha512_base64($data, $key)>
634 =item B<hmac_sha512224_base64($data, $key)>
636 =item B<hmac_sha512256_base64($data, $key)>
638 Returns the HMAC-SHA-1/224/256/384/512 digest of I<$data>/I<$key>,
639 with the result encoded as a Base64 string. Multiple I<$data>
640 arguments are allowed, provided that I<$key> is the last argument
643 It's important to note that the resulting string does B<not> contain
644 the padding characters typical of Base64 encodings. This omission is
645 deliberate, and is done to maintain compatibility with the family of
646 CPAN Digest modules. See L</"PADDING OF BASE64 DIGESTS"> for details.
652 L<Digest>, L<Digest::SHA::PurePerl>
654 The Secure Hash Standard (Draft FIPS PUB 180-4) can be found at:
656 L<http://csrc.nist.gov/publications/drafts/fips180-4/Draft-FIPS180-4_Feb2011.pdf>
658 The Keyed-Hash Message Authentication Code (HMAC):
660 L<http://csrc.nist.gov/publications/fips/fips198/fips-198a.pdf>
664 Mark Shelor <mshelor@cpan.org>
666 =head1 ACKNOWLEDGMENTS
668 The author is particularly grateful to
688 "who by trained skill rescued life from such great billows and such thick
689 darkness and moored it in so perfect a calm and in so brilliant a light"
692 =head1 COPYRIGHT AND LICENSE
694 Copyright (C) 2003-2011 Mark Shelor
696 This library is free software; you can redistribute it and/or modify
697 it under the same terms as Perl itself.