NAME

File::BSED - Search/Replace in Binary Files.

VERSION

This document describes File::BSED version 0.5

SYNOPSIS

use File::BSED qw(binary_search_replace binary_file_matches);

# search/replace
my $matches = binary_search_replace({
    search  => 'ff3cea3f0013',
    replace => 'b801000000c3',
    infile  => '/bin/ls',
    outfile => '/tmp/ls.patched'
});
if ($matches == -1) {
    my $error_string = File::BSED->errtostr();
    die "Error: $error_string\n";
}
print "Replaced $matches time(s)\n";

# search
my $matches = binary_file_matches('ff3cea3f0013', '/bin/ls');
print "Matched $matches time(s)\n";

# replace 'gnu' to 'bsd'
my $hex_gnu = File::BSED::string_to_hexstring('gnu');
my $hex_bsd = File::BSED::string_to_hexstring('bsd');
my $matches = binary_search_replace({
    search  => $hex_gnu,
    replace => $hex_bsd,
    infile  => '/bin/ls',
    outfile => 'ls.bsd',
});
# [...]

DESCRIPTION

This is a perl-binding to libgbsed, a binary stream editor.

gbsed lets you search and replace binary data in binary files by using hex values in text strings as search patterns. You can also use wildcard matches with ??, which will match any wide byte.

These are all valid search strings:

search => "0xffc300193ab2f63a";
search => "0xff??00??3ab2f??a";
search => "FF??00??3AB2F??A";

while these are not:

search => "the quick brown fox"; # only hex, no text. you would have to
                                 # convert the text to hex first.
search => "0xff?c33ab3?accc";    # no nybbles only wide bytes. (?? not ?).

SUBROUTINES/METHODS

CLASS METHODS

binary_search_replace(\%arguments)

Search and replace in a binary file. Valid arguments are:

The pattern to search for. Must be a string with hex digits.

replace

What to replace with. Must be a string with hex digits. (Probably a very good idea that it is the same length as the search pattern).

infile

The filename of the file to search in.

outfile

The filename of the file to save changes to.

minmatch

Need at least $minmatch matches before any work.

maxmatch

Stop after $maxmatch matches.

bsed returns the number of times the search string was found in the file, or -1 if an error occurred. When an error occurs the error number can be found with errno and you can get a description of the error with errtostr.

Example:

my $number_of_matches = binary_search_replace({
    search  => '0xff',
    replace => '0x00',
    
    infile  => '/bin/ls',
    outfile => '/bin/ls.patched',
});

if ($number_of_matches = -1) {
    die sprintf("ERROR: %s\n", File::BSED->errtostr());
}
print "Replaced $number_of_matches time(s).\n";

gbsed(\%arguments)

Alias to binary_search_replace for backward compatibility.

binary_file_matches($search_pattern, $input_file)

Return the number of times $search_pattern is found in binary file. Search pattern must be a string of hex digits.

Example:

my $number_of_matches = binary_file_matches('0xfeedface', '/bin/ls');
print "Matched $number_of_matches time(s)\n";

string_to_hexstring($text)

Convert text to a string of ASCII hex values.

ERROR HANDLING

errtostr

This function returns a string describing what happened. if an error has occurred with either binary_search_matches or binary_file_matches (they return -1 on error).

errno

This function returns the error number if an error has occurred with either binary_search_replace or binary_file_matches (they return -1 on error).

Use errtostr instead.

WARNINGS

warnings()

Returns an array ref to any warnings raised.

Example:

my @warnings = @{ File::BSED::warnings() };
for my $warning (@warnings) {
    warn "Warning: $warning\n";
}

DIAGNOSTICS

CONFIGURATION AND ENVIRONMENT

This module requires no configuration file or environment variables.

DEPENDENCIES

  • A working C compiler.

INCOMPATIBILITIES

None known.

BUGS AND LIMITATIONS

No bugs have been reported.

Please report any bugs or feature requests to bug-file-bsed@rt.cpan.org, or through the web interface at http://rt.cpan.org.

SEE ALSO

AUTHOR

by Ask Solem, ask@0x61736b.net.

ACKNOWLEDGEMENTS

Dave Dykstra dwdbsed@drdykstra.us. for bsed the original program,

0xfeedface for the wildcards patch.

LICENSE AND COPYRIGHT

Copyright (c), 2007 Ask Solem ask@0x61736b.net.

SEE

perlartistic perlgpl

All rights reserved.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.6 or, at your option, any later version of Perl 5 you may have available.

DISCLAIMER OF WARRANTY

BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE SOFTWARE, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE SOFTWARE "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE SOFTWARE IS WITH YOU. SHOULD THE SOFTWARE PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR, OR CORRECTION.

IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE SOFTWARE AS PERMITTED BY THE ABOVE LICENCE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE SOFTWARE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE SOFTWARE TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.