735 lines
16 KiB
Perl
735 lines
16 KiB
Perl
# Copyright (c) 2000-2005 Graham Barr <gbarr@pobox.com>. All rights reserved.
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# This program is free software; you can redistribute it and/or
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# modify it under the same terms as Perl itself.
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package Convert::ASN1;
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{
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$Convert::ASN1::VERSION = '0.27';
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}
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use strict;
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use warnings;
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BEGIN {
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local $SIG{__DIE__};
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eval { require bytes and 'bytes'->import };
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}
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# These are the subs that do the decode, they are called with
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# 0 1 2 3 4
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# $optn, $op, $stash, $var, $buf
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# The order must be the same as the op definitions above
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my @decode = (
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sub { die "internal error\n" },
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\&_dec_boolean,
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\&_dec_integer,
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\&_dec_bitstring,
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\&_dec_string,
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\&_dec_null,
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\&_dec_object_id,
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\&_dec_real,
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\&_dec_sequence,
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\&_dec_explicit,
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\&_dec_set,
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\&_dec_time,
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\&_dec_time,
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\&_dec_utf8,
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undef, # ANY
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undef, # CHOICE
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\&_dec_object_id,
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\&_dec_bcd,
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);
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my @ctr;
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@ctr[opBITSTR, opSTRING, opUTF8] = (\&_ctr_bitstring,\&_ctr_string,\&_ctr_string);
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sub _decode {
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my ($optn, $ops, $stash, $pos, $end, $seqof, $larr) = @_;
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my $idx = 0;
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# we try not to copy the input buffer at any time
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foreach my $buf ($_[-1]) {
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OP:
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foreach my $op (@{$ops}) {
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my $var = $op->[cVAR];
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if (length $op->[cTAG]) {
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TAGLOOP: {
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my($tag,$len,$npos,$indef) = _decode_tl($buf,$pos,$end,$larr)
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or do {
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next OP if $pos==$end and ($seqof || defined $op->[cEXT]);
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die "decode error";
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};
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if ($tag eq $op->[cTAG]) {
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&{$decode[$op->[cTYPE]]}(
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$optn,
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$op,
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$stash,
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# We send 1 if there is not var as if there is the decode
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# should be getting undef. So if it does not get undef
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# it knows it has no variable
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($seqof ? $seqof->[$idx++] : defined($var) ? $stash->{$var} : ref($stash) eq 'SCALAR' ? $$stash : 1),
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$buf,$npos,$len, $larr
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);
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$pos = $npos+$len+$indef;
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redo TAGLOOP if $seqof && $pos < $end;
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next OP;
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}
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if ($tag eq ($op->[cTAG] | pack("C",ASN_CONSTRUCTOR))
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and my $ctr = $ctr[$op->[cTYPE]])
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{
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_decode(
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$optn,
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[$op],
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undef,
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$npos,
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$npos+$len,
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(\my @ctrlist),
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$larr,
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$buf,
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);
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($seqof ? $seqof->[$idx++] : defined($var) ? $stash->{$var} : ref($stash) eq 'SCALAR' ? $$stash : undef)
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= &{$ctr}(@ctrlist);
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$pos = $npos+$len+$indef;
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redo TAGLOOP if $seqof && $pos < $end;
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next OP;
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}
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if ($seqof || defined $op->[cEXT]) {
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next OP;
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}
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die "decode error " . unpack("H*",$tag) ."<=>" . unpack("H*",$op->[cTAG]), " ",$pos," ",$op->[cTYPE]," ",$op->[cVAR]||'';
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}
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}
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else { # opTag length is zero, so it must be an ANY, CHOICE or EXTENSIONS
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if ($op->[cTYPE] == opANY) {
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ANYLOOP: {
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my($tag,$len,$npos,$indef) = _decode_tl($buf,$pos,$end,$larr)
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or do {
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next OP if $pos==$end and ($seqof || defined $op->[cEXT]);
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die "decode error";
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};
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$len += $npos - $pos + $indef;
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my $handler;
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if ($op->[cDEFINE]) {
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$handler = $optn->{oidtable} && $optn->{oidtable}{$stash->{$op->[cDEFINE]}};
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$handler ||= $optn->{handlers}{$op->[cVAR]}{$stash->{$op->[cDEFINE]}};
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}
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($seqof ? $seqof->[$idx++] : ref($stash) eq 'SCALAR' ? $$stash : $stash->{$var})
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= $handler ? $handler->decode(substr($buf,$pos,$len)) : substr($buf,$pos,$len);
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$pos += $len;
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redo ANYLOOP if $seqof && $pos < $end;
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}
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}
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elsif ($op->[cTYPE] == opCHOICE) {
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CHOICELOOP: {
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my($tag,$len,$npos,$indef) = _decode_tl($buf,$pos,$end,$larr)
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or do {
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next OP if $pos==$end and ($seqof || defined $op->[cEXT]);
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die "decode error";
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};
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my $extensions;
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foreach my $cop (@{$op->[cCHILD]}) {
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if ($tag eq $cop->[cTAG]) {
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my $nstash = $seqof
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? ($seqof->[$idx++]={})
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: defined($var)
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? ($stash->{$var}={})
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: ref($stash) eq 'SCALAR'
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? ($$stash={}) : $stash;
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&{$decode[$cop->[cTYPE]]}(
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$optn,
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$cop,
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$nstash,
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($cop->[cVAR] ? $nstash->{$cop->[cVAR]} : undef),
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$buf,$npos,$len,$larr,
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);
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$pos = $npos+$len+$indef;
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redo CHOICELOOP if $seqof && $pos < $end;
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next OP;
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}
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if ($cop->[cTYPE] == opEXTENSIONS) {
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$extensions = 1;
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next;
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}
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unless (length $cop->[cTAG]) {
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eval {
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_decode(
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$optn,
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[$cop],
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(\my %tmp_stash),
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$pos,
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$npos+$len+$indef,
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undef,
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$larr,
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$buf,
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);
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my $nstash = $seqof
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? ($seqof->[$idx++]={})
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: defined($var)
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? ($stash->{$var}={})
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: ref($stash) eq 'SCALAR'
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? ($$stash={}) : $stash;
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@{$nstash}{keys %tmp_stash} = values %tmp_stash;
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} or next;
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$pos = $npos+$len+$indef;
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redo CHOICELOOP if $seqof && $pos < $end;
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next OP;
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}
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if ($tag eq ($cop->[cTAG] | pack("C",ASN_CONSTRUCTOR))
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and my $ctr = $ctr[$cop->[cTYPE]])
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{
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my $nstash = $seqof
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? ($seqof->[$idx++]={})
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: defined($var)
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? ($stash->{$var}={})
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: ref($stash) eq 'SCALAR'
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? ($$stash={}) : $stash;
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_decode(
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$optn,
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[$cop],
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undef,
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$npos,
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$npos+$len,
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(\my @ctrlist),
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$larr,
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$buf,
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);
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$nstash->{$cop->[cVAR]} = &{$ctr}(@ctrlist);
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$pos = $npos+$len+$indef;
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redo CHOICELOOP if $seqof && $pos < $end;
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next OP;
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}
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}
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if ($pos < $end && $extensions) {
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$pos = $npos+$len+$indef;
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redo CHOICELOOP if $seqof && $pos < $end;
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next OP;
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}
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}
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die "decode error" unless $op->[cEXT];
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}
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elsif ($op->[cTYPE] == opEXTENSIONS) {
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$pos = $end; # Skip over the rest
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}
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else {
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die "this point should never be reached";
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}
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}
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}
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}
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die "decode error $pos $end" unless $pos == $end;
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}
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sub _dec_boolean {
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# 0 1 2 3 4 5 6
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# $optn, $op, $stash, $var, $buf, $pos, $len
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$_[3] = unpack("C",substr($_[4],$_[5],1)) ? 1 : 0;
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1;
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}
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sub _dec_integer {
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# 0 1 2 3 4 5 6
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# $optn, $op, $stash, $var, $buf, $pos, $len
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my $buf = substr($_[4],$_[5],$_[6]);
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my $tmp = unpack("C",$buf) & 0x80 ? pack("C",255) : pack("C",0);
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if ($_[6] > 4) {
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$_[3] = os2ip($buf, $_[0]->{decode_bigint} || 'Math::BigInt');
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} else {
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# N unpacks an unsigned value
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$_[3] = unpack("l",pack("l",unpack("N", $tmp x (4-$_[6]) . $buf)));
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}
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1;
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}
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sub _dec_bitstring {
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# 0 1 2 3 4 5 6
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# $optn, $op, $stash, $var, $buf, $pos, $len
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$_[3] = [ substr($_[4],$_[5]+1,$_[6]-1), ($_[6]-1)*8-unpack("C",substr($_[4],$_[5],1)) ];
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1;
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}
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sub _dec_string {
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# 0 1 2 3 4 5 6
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# $optn, $op, $stash, $var, $buf, $pos, $len
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$_[3] = substr($_[4],$_[5],$_[6]);
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1;
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}
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sub _dec_null {
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# 0 1 2 3 4 5 6
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# $optn, $op, $stash, $var, $buf, $pos, $len
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$_[3] = exists($_[0]->{decode_null}) ? $_[0]->{decode_null} : 1;
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1;
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}
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sub _dec_object_id {
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# 0 1 2 3 4 5 6
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# $optn, $op, $stash, $var, $buf, $pos, $len
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my @data = unpack("w*",substr($_[4],$_[5],$_[6]));
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if ($_[1]->[cTYPE] == opOBJID and @data > 1) {
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if ($data[0] < 40) {
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splice(@data, 0, 1, 0, $data[0]);
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}
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elsif ($data[0] < 80) {
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splice(@data, 0, 1, 1, $data[0] - 40);
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}
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else {
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splice(@data, 0, 1, 2, $data[0] - 80);
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}
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}
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$_[3] = join(".", @data);
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1;
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}
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my @_dec_real_base = (2,8,16);
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sub _dec_real {
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# 0 1 2 3 4 5 6
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# $optn, $op, $stash, $var, $buf, $pos, $len
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$_[3] = 0.0, return unless $_[6];
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my $first = unpack("C",substr($_[4],$_[5],1));
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if ($first & 0x80) {
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# A real number
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require POSIX;
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my $exp;
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my $expLen = $first & 0x3;
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my $estart = $_[5]+1;
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if($expLen == 3) {
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$estart++;
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$expLen = unpack("C",substr($_[4],$_[5]+1,1));
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}
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else {
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$expLen++;
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}
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_dec_integer(undef, undef, undef, $exp, $_[4],$estart,$expLen);
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my $mant = 0.0;
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for (reverse unpack("C*",substr($_[4],$estart+$expLen,$_[6]-1-$expLen))) {
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$exp +=8, $mant = (($mant+$_) / 256) ;
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}
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$mant *= 1 << (($first >> 2) & 0x3);
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$mant = - $mant if $first & 0x40;
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$_[3] = $mant * POSIX::pow($_dec_real_base[($first >> 4) & 0x3], $exp);
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return;
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}
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elsif($first & 0x40) {
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$_[3] = POSIX::HUGE_VAL(),return if $first == 0x40;
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$_[3] = - POSIX::HUGE_VAL(),return if $first == 0x41;
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}
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elsif(substr($_[4],$_[5],$_[6]) =~ /^.([-+]?)0*(\d+(?:\.\d+(?:[Ee][-+]?\d+)?)?)$/s) {
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$_[3] = eval "$1$2";
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return;
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}
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die "REAL decode error\n";
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}
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sub _dec_explicit {
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# 0 1 2 3 4 5 6 7
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# $optn, $op, $stash, $var, $buf, $pos, $len, $larr
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local $_[1][cCHILD][0][cVAR] = $_[1][cVAR] unless $_[1][cCHILD][0][cVAR];
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_decode(
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$_[0], #optn
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$_[1]->[cCHILD], #ops
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$_[2], #stash
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$_[5], #pos
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$_[5]+$_[6], #end
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undef, #loop
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$_[7],
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$_[4], #buf
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);
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1;
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}
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sub _dec_sequence {
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# 0 1 2 3 4 5 6 7
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# $optn, $op, $stash, $var, $buf, $pos, $len, $larr
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if (defined( my $ch = $_[1]->[cCHILD])) {
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_decode(
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$_[0], #optn
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$ch, #ops
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(defined($_[3]) || $_[1]->[cLOOP]) ? $_[2] : ($_[3]= {}), #stash
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$_[5], #pos
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$_[5]+$_[6], #end
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$_[1]->[cLOOP] && ($_[3]=[]), #loop
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$_[7],
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$_[4], #buf
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);
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}
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else {
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$_[3] = substr($_[4],$_[5],$_[6]);
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}
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1;
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}
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sub _dec_set {
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# 0 1 2 3 4 5 6 7
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# $optn, $op, $stash, $var, $buf, $pos, $len, $larr
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# decode SET OF the same as SEQUENCE OF
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my $ch = $_[1]->[cCHILD];
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goto &_dec_sequence if $_[1]->[cLOOP] or !defined($ch);
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my ($optn, $pos, $larr) = @_[0,5,7];
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my $stash = defined($_[3]) ? $_[2] : ($_[3]={});
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my $end = $pos + $_[6];
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my @done;
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my $extensions;
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while ($pos < $end) {
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my($tag,$len,$npos,$indef) = _decode_tl($_[4],$pos,$end,$larr)
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or die "decode error";
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my ($idx, $any, $done) = (-1);
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SET_OP:
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foreach my $op (@$ch) {
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$idx++;
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if (length($op->[cTAG])) {
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if ($tag eq $op->[cTAG]) {
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my $var = $op->[cVAR];
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&{$decode[$op->[cTYPE]]}(
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$optn,
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$op,
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$stash,
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# We send 1 if there is not var as if there is the decode
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# should be getting undef. So if it does not get undef
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# it knows it has no variable
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(defined($var) ? $stash->{$var} : 1),
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$_[4],$npos,$len,$larr,
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);
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$done = $idx;
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last SET_OP;
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}
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if ($tag eq ($op->[cTAG] | pack("C",ASN_CONSTRUCTOR))
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and my $ctr = $ctr[$op->[cTYPE]])
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{
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_decode(
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$optn,
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[$op],
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undef,
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$npos,
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$npos+$len,
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(\my @ctrlist),
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$larr,
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$_[4],
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);
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$stash->{$op->[cVAR]} = &{$ctr}(@ctrlist)
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if defined $op->[cVAR];
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$done = $idx;
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last SET_OP;
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}
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next SET_OP;
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}
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elsif ($op->[cTYPE] == opANY) {
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$any = $idx;
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}
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elsif ($op->[cTYPE] == opCHOICE) {
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my $var = $op->[cVAR];
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foreach my $cop (@{$op->[cCHILD]}) {
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if ($tag eq $cop->[cTAG]) {
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my $nstash = defined($var) ? ($stash->{$var}={}) : $stash;
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&{$decode[$cop->[cTYPE]]}(
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$optn,
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$cop,
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$nstash,
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$nstash->{$cop->[cVAR]},
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$_[4],$npos,$len,$larr,
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);
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$done = $idx;
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last SET_OP;
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}
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if ($tag eq ($cop->[cTAG] | pack("C",ASN_CONSTRUCTOR))
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and my $ctr = $ctr[$cop->[cTYPE]])
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{
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my $nstash = defined($var) ? ($stash->{$var}={}) : $stash;
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_decode(
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$optn,
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[$cop],
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undef,
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$npos,
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$npos+$len,
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(\my @ctrlist),
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$larr,
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$_[4],
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);
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$nstash->{$cop->[cVAR]} = &{$ctr}(@ctrlist);
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$done = $idx;
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last SET_OP;
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}
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}
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}
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elsif ($op->[cTYPE] == opEXTENSIONS) {
|
|
$extensions = $idx;
|
|
}
|
|
else {
|
|
die "internal error";
|
|
}
|
|
}
|
|
|
|
if (!defined($done) and defined($any)) {
|
|
my $var = $ch->[$any][cVAR];
|
|
$stash->{$var} = substr($_[4],$pos,$len+$npos-$pos) if defined $var;
|
|
$done = $any;
|
|
}
|
|
|
|
if( !defined($done) && defined($extensions) ) {
|
|
$done = $extensions;
|
|
}
|
|
|
|
die "decode error" if !defined($done) or $done[$done]++;
|
|
|
|
$pos = $npos + $len + $indef;
|
|
}
|
|
|
|
die "decode error" unless $end == $pos;
|
|
|
|
foreach my $idx (0..$#{$ch}) {
|
|
die "decode error" unless $done[$idx] or $ch->[$idx][cEXT] or $ch->[$idx][cTYPE] == opEXTENSIONS;
|
|
}
|
|
|
|
1;
|
|
}
|
|
|
|
|
|
my %_dec_time_opt = ( unixtime => 0, withzone => 1, raw => 2);
|
|
|
|
sub _dec_time {
|
|
# 0 1 2 3 4 5 6
|
|
# $optn, $op, $stash, $var, $buf, $pos, $len
|
|
|
|
my $mode = $_dec_time_opt{$_[0]->{'decode_time'} || ''} || 0;
|
|
|
|
if ($mode == 2 or $_[6] == 0) {
|
|
$_[3] = substr($_[4],$_[5],$_[6]);
|
|
return;
|
|
}
|
|
|
|
my @bits = (substr($_[4],$_[5],$_[6])
|
|
=~ /^((?:\d\d)?\d\d)(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)((?:\.\d{1,3})?)(([-+])(\d\d)(\d\d)|Z)/)
|
|
or die "bad time format";
|
|
|
|
if ($bits[0] < 100) {
|
|
$bits[0] += 100 if $bits[0] < 50;
|
|
}
|
|
else {
|
|
$bits[0] -= 1900;
|
|
}
|
|
$bits[1] -= 1;
|
|
require Time::Local;
|
|
my $time = Time::Local::timegm(@bits[5,4,3,2,1,0]);
|
|
$time += $bits[6] if length $bits[6];
|
|
my $offset = 0;
|
|
if ($bits[7] ne 'Z') {
|
|
$offset = $bits[9] * 3600 + $bits[10] * 60;
|
|
$offset = -$offset if $bits[8] eq '-';
|
|
$time -= $offset;
|
|
}
|
|
$_[3] = $mode ? [$time,$offset] : $time;
|
|
}
|
|
|
|
|
|
sub _dec_utf8 {
|
|
# 0 1 2 3 4 5 6
|
|
# $optn, $op, $stash, $var, $buf, $pos, $len
|
|
|
|
BEGIN {
|
|
unless (CHECK_UTF8) {
|
|
local $SIG{__DIE__};
|
|
eval { require bytes } and 'bytes'->unimport;
|
|
eval { require utf8 } and 'utf8'->import;
|
|
}
|
|
}
|
|
|
|
if (CHECK_UTF8) {
|
|
$_[3] = Encode::decode('utf8', substr($_[4],$_[5],$_[6]));
|
|
}
|
|
else {
|
|
$_[3] = (substr($_[4],$_[5],$_[6]) =~ /(.*)/s)[0];
|
|
}
|
|
|
|
1;
|
|
}
|
|
|
|
|
|
sub _decode_tl {
|
|
my($pos,$end,$larr) = @_[1,2,3];
|
|
|
|
return if $pos >= $end;
|
|
|
|
my $indef = 0;
|
|
|
|
my $tag = substr($_[0], $pos++, 1);
|
|
|
|
if((unpack("C",$tag) & 0x1f) == 0x1f) {
|
|
my $b;
|
|
my $n=1;
|
|
do {
|
|
return if $pos >= $end;
|
|
$tag .= substr($_[0],$pos++,1);
|
|
$b = ord substr($tag,-1);
|
|
} while($b & 0x80);
|
|
}
|
|
return if $pos >= $end;
|
|
|
|
my $len = ord substr($_[0],$pos++,1);
|
|
|
|
if($len & 0x80) {
|
|
$len &= 0x7f;
|
|
|
|
if ($len) {
|
|
return if $pos+$len > $end ;
|
|
|
|
my $padding = $len < 4 ? "\0" x (4 - $len) : "";
|
|
($len,$pos) = (unpack("N", $padding . substr($_[0],$pos,$len)), $pos+$len);
|
|
}
|
|
else {
|
|
unless (exists $larr->{$pos}) {
|
|
_scan_indef($_[0],$pos,$end,$larr) or return;
|
|
}
|
|
$indef = 2;
|
|
$len = $larr->{$pos};
|
|
}
|
|
}
|
|
|
|
return if $pos+$len+$indef > $end;
|
|
|
|
# return the tag, the length of the data, the position of the data
|
|
# and the number of extra bytes for indefinate encoding
|
|
|
|
($tag, $len, $pos, $indef);
|
|
}
|
|
|
|
sub _scan_indef {
|
|
my($pos,$end,$larr) = @_[1,2,3];
|
|
my @depth = ( $pos );
|
|
|
|
while(@depth) {
|
|
return if $pos+2 > $end;
|
|
|
|
if (substr($_[0],$pos,2) eq "\0\0") {
|
|
my $end = $pos;
|
|
my $stref = shift @depth;
|
|
# replace pos with length = end - pos
|
|
$larr->{$stref} = $end - $stref;
|
|
$pos += 2;
|
|
next;
|
|
}
|
|
|
|
my $tag = substr($_[0], $pos++, 1);
|
|
|
|
if((unpack("C",$tag) & 0x1f) == 0x1f) {
|
|
my $b;
|
|
do {
|
|
$tag .= substr($_[0],$pos++,1);
|
|
$b = ord substr($tag,-1);
|
|
} while($b & 0x80);
|
|
}
|
|
return if $pos >= $end;
|
|
|
|
my $len = ord substr($_[0],$pos++,1);
|
|
|
|
if($len & 0x80) {
|
|
if ($len &= 0x7f) {
|
|
return if $pos+$len > $end ;
|
|
|
|
my $padding = $len < 4 ? "\0" x (4 - $len) : "";
|
|
$pos += $len + unpack("N", $padding . substr($_[0],$pos,$len));
|
|
}
|
|
else {
|
|
# reserve another list element
|
|
unshift @depth, $pos;
|
|
}
|
|
}
|
|
else {
|
|
$pos += $len;
|
|
}
|
|
}
|
|
|
|
1;
|
|
}
|
|
|
|
sub _ctr_string { join '', @_ }
|
|
|
|
sub _ctr_bitstring {
|
|
[ join('', map { $_->[0] } @_), $_[-1]->[1] ]
|
|
}
|
|
|
|
sub _dec_bcd {
|
|
# 0 1 2 3 4 5 6
|
|
# $optn, $op, $stash, $var, $buf, $pos, $len
|
|
|
|
($_[3] = unpack("H*", substr($_[4],$_[5],$_[6]))) =~ s/[fF]$//;
|
|
1;
|
|
}
|
|
1;
|
|
|