How to read encrypted data from informix database into a single variable

Dev has asked for the wisdom of the Perl Monks concerning the following question:

I want to read a field of char(32) type, from an informix database table.And contents of this field, is in encrypted form.So it contains, new line characters also. I want to dump contents from this field(as it is) into a single variable and later use the same, for decrypting it.

Part of what i have done is , as follows , But it is'nt working as intended because of new line characters.

open (ki_file, ">ki_file.txt") or
            die ("\n\nCould not open file. $!\n\n");  
# Open file to dump ki_token from table
print "\n ki_file.txt opened for output\n";

undef $/;            # Undefining end of record character

$stmt = "SELECT ki from imsi_period where imsi_id=346 "; 
# ki is field, containing encrypted data
$sth = $dbh->prepare($stmt);
$sth->{ChopBlanks} = 1;
$sth->execute();
$sth->bind_col(1,\$ki_token,{TYPE => SQL_CHAR});
while ($sth->fetch) {
         # print $ki_token;
           print ki_file ($ki_token);
           print "Ki_Token is written to ki_file.txt."
       }

$/ = "\n";           # Restore end of record character for normal beha
+viour later

close (ki_file);     # Close file 

......
[download]

Comment on How to read encrypted data from informix database into a single variable Download Code

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Re: How to read encrypted data from informix database into a single variable by jettero (Monsignor) on May 15, 2007 at 12:27 UTC
I could be going it alone (in which case: sorry); but I don't seem to understand what doesn't work or what it is that you intend `undef $/` to do. I don't think `$/` applies in any way when using DBI, but I could be mistaken about that too. Do you want to somehow escape the newlines before writing them to `ki_file.txt`? You'd have to pick some standard way to do so if that's what you're intending. Personally, I'd probably choose to dump a hex or base64 representation to file: `# note that part of your trouble could be your antiquated file-handle +representation (doubtful). open my $output_file, ">", "ki_file.txt" or die $!; # unpack can be a little arcane... print $output_file unpack("H*", $ki_token), "\n";` [download] The best document on unpack is actually pack. Please correct me if I've completely missed the point of the question. -Paul	[reply] [d/l] [select]
Re^2: How to read encrypted data from informix database into a single variable by Dev (Initiate) on May 15, 2007 at 13:28 UTC
@jettero : I am working with archaic system and new to Perl :) Yes, i thing i will try to dump a hex and work on it. It sounds better. I will give it a shot. I have taken, hex unload to a file. It contains around 25,000 records. It is not possible to extract a single record (unique keys are such, that i cannot use them at runtime). So now i want to read , 32 bytes of this file ( the hex dump) at a time (in an scalar variable) and skip 2 bytes after - each 32 byte read. can you suggest me a way to do this!	[reply]
Re^3: How to read encrypted data from informix database into a single variable by jettero (Monsignor) on May 15, 2007 at 13:44 UTC
You generate the output file yourself, so I'd make sure to only write 32bytes per line — while simultaneously avoiding writing the two mystery bytes — and just read them back in that way. no? `while(<$input>) { chomp; my $var = pack("H*", $_); die "holy smokes, my hex-dump file is bad" unless length $var == 3 +2; }` [download] -Paul	[reply] [d/l]
Re^4: How to read encrypted data from informix database into a single variable by Dev (Initiate) on May 16, 2007 at 09:07 UTC
Re: How to read encrypted data from informix database into a single variable by shmem (Chancellor) on May 15, 2007 at 12:39 UTC
If you are on Windows, any "\n" in the token might be converted to "\r\n" on output; undefining $/ doesn't fix that. See binmode. --shmem _($_=" "x(1<<5)."?\n".q·/)Oo. G°\ / /\_¯/(q / ---------------------------- \__(m.====·.(_("always off the crowd"))."· ");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}	[reply]
Re^2: How to read encrypted data from informix database into a single variable by Dev (Initiate) on May 15, 2007 at 13:32 UTC
No, i am on HP-UX. i think working with hex dump, would be an better option for my problem I have taken, hex unload to a file. It contains around 25,000 records. It is not possible to extract a single record (unique keys are such, that i cannot use them at runtime). So now i want to read , 32 bytes of this file ( the hex dump) at a time (in an scalar variable) and skip 2 bytes after - each 32 byte read. can you suggest me a way to do this!	[reply]
Re^3: How to read encrypted data from informix database into a single variable by shmem (Chancellor) on May 15, 2007 at 13:41 UTC
Well, I'd do something along these lines.. `open my $fh, '<', $file or die "Can't read '$file': $!\n"; while((my $len = read $fh, my $record, 32) == 32) { # do something with $record ... (read $fh, my $junk, 2) == 2 or last; }` [download] Oh wait... yes, use strict, use warnings :-) --shmem _($_=" "x(1<<5)."?\n".q·/)Oo. G°\ / /\_¯/(q / ---------------------------- \__(m.====·.(_("always off the crowd"))."· ");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}	[reply] [d/l]
Re^4: How to read encrypted data from informix database into a single variable by Dev (Initiate) on May 16, 2007 at 09:10 UTC