[joern@zyn.de - Sun Jun 1 18:10:07 2003]:
Show quoted text> So I'm currently working on a patch, which enables handling encoded data
> with MIME::Parser, MIME::Entity and MIME::Body, which resolves this
> issue.
I created this patch and sent it to the maintainer of MIME-tools. He was
not sure, if he accepts it, because it introduces a non-decoded mode,
which changes the semantics signficantly resp. break some parts of the
module (which are not relevant for our problem of making signature
checking possible).
Anyway I attach the patch here (for MIME-tools 5.411), because it's the
only currently known way to make signature checking with Mail::GnuPG work ;)
The patch adds a new method, which tells MIME::Parser to omit decoding:
$parser->dont_decode_bodies(1);
An entity created with this parser can be passed to Mail::GnuPG->verify.
MIME::Entity->print_bodyhandle() gives the original encoded data, but
you can't get decoded data from such an entity. You have to decode it
yourself, if you need decoded data from it!
Regards,
Joern
diff -ur MIME-tools-5.411.orig/lib/MIME/Body.pm MIME-tools-5.411/lib/MIME/Body.pm
--- MIME-tools-5.411.orig/lib/MIME/Body.pm 2000-11-04 20:54:46.000000000 +0100
+++ MIME-tools-5.411/lib/MIME/Body.pm 2003-06-02 00:37:39.000000000 +0200
@@ -239,6 +239,23 @@
#------------------------------
+=item is_encoded [ONOFF]
+
+I<Instance method.>
+If set to yes, no decoding is applied on output. This flag is set
+by MIME::Parser, if the parser runs in dont_decode(1) mode, so the
+content is handled transparent and completely unmodified.
+
+=cut
+
+sub is_encoded {
+ my ($self, $yesno) = @_;
+ $self->{MB_IsEncoded} = $yesno if (@_ > 1);
+ $self->{MB_IsEncoded};
+}
+
+#------------------------------
+
=item dup
I<Instance method.>
diff -ur MIME-tools-5.411.orig/lib/MIME/Entity.pm MIME-tools-5.411/lib/MIME/Entity.pm
--- MIME-tools-5.411.orig/lib/MIME/Entity.pm 2000-11-06 12:58:53.000000000 +0100
+++ MIME-tools-5.411/lib/MIME/Entity.pm 2003-06-02 00:40:58.000000000 +0200
@@ -1846,14 +1846,21 @@
my ($self, $out) = @_;
$out = wraphandle($out || select); ### get a printable output
- ### Get the encoding, defaulting to "binary" if unsupported:
- my $encoding = ($self->head->mime_encoding || 'binary');
- my $decoder = best MIME::Decoder $encoding;
- $decoder->head($self->head); ### associate with head, if any
-
### Output the body:
my $IO = $self->open("r") || die "open body: $!";
- $decoder->encode($IO, $out) || return error "encoding failed";
+ if ( $self->bodyhandle->is_encoded ) {
+ ### Transparent mode: data is already encoded, so no
+ ### need to encode it again
+ my $buf;
+ $out->print($buf) while ($IO->read($buf, 2048));
+ } else {
+ ### Get the encoding, defaulting to "binary" if unsupported:
+ my $encoding = ($self->head->mime_encoding || 'binary');
+ my $decoder = best MIME::Decoder $encoding;
+ $decoder->head($self->head); ### associate with head, if any
+ $decoder->encode($IO, $out) || return error "encoding failed";
+ }
+
$IO->close;
1;
}
diff -ur MIME-tools-5.411.orig/lib/MIME/Parser.pm MIME-tools-5.411/lib/MIME/Parser.pm
--- MIME-tools-5.411.orig/lib/MIME/Parser.pm 2000-11-12 06:55:11.000000000 +0100
+++ MIME-tools-5.411/lib/MIME/Parser.pm 2003-06-02 23:20:19.000000000 +0200
@@ -471,8 +471,37 @@
}
+#------------------------------
+
+=item dont_decode_bodies [YESNO]
+
+I<Instance method.>
+Controls whether the parser should decode entity bodies or not.
+If this is set to a true value (default is false), all entity bodies
+will be kept as-is in the original content-transfer encoding.
+
+To prevent double encoding on the output side MIME::Body->is_encoded
+is set, which tells MIME::Body not to encode the data agin, if encoded
+data is requested. This is in particular useful, when it's importat that
+the content B<must not> be modified, e.g. if you want to calculate
+OpenPGP signatures from it.
+
+B<WARNING>: the semantics change significantly if you parse MIME
+messages with this option set, because MIME::Entity resp. MIME::Body
+*always* see encoded data now, while the default behaviour is
+working with *decoded* data (and encoding it only if you request it).
+You need to decode the data yourself, if you want to have it decoded.
+
+So use this option only if you exactly know, what you're doing, and
+that you're sure, that you really need it ;)
+=cut
+sub dont_decode_bodies {
+ my ($self, $yesno) = @_;
+ $self->{MP5_DontDecodeBodies} = $yesno if (@_ > 1);
+ $self->{MP5_DontDecodeBodies};
+}
#------------------------------
#
@@ -781,6 +810,10 @@
$ENCODED->seek(0, 0);
}
+ ### Open a new bodyhandle for outputting the data:
+ my $body = $self->new_body_for($head) || die "$ME: no body\n"; # gotta die
+ $body->binmode(1) unless textual_type($ent->effective_type);
+
### Get a content-decoder to decode this part's encoding:
my $encoding = $head->mime_encoding;
my $decoder = new MIME::Decoder $encoding;
@@ -790,41 +823,52 @@
"application/octet-stream."); ### as per RFC-2045
$ent->effective_type('application/octet-stream');
$decoder = new MIME::Decoder 'binary';
+ $encoding = 'binary';
}
- ### If desired, sidetrack to troll for UUENCODE:
- $self->debug("extract uuencode? ", $self->extract_uuencode);
- $self->debug("encoding? ", $encoding);
- $self->debug("effective type? ", $ent->effective_type);
- if ($self->extract_uuencode and
- ($encoding =~ /^(7bit|8bit|binary)\Z/) and
- ($ent->effective_type =~ m{^text/plain\Z})) {
-
- ### Hunt for it:
- my $uu_ent = eval { $self->hunt_for_uuencode($ENCODED, $ent) };
- if ($uu_ent) { ### snark
- %$ent = %$uu_ent;
- return 1;
- }
- else { ### boojum
- $self->whine("while hunting for uuencode: $@");
- $ENCODED->seek(0,0);
- }
+ ### Data should be stored decoded?
+ if ( !$self->dont_decode_bodies ) {
+
+ ### If desired, sidetrack to troll for UUENCODE:
+ $self->debug("extract uuencode? ", $self->extract_uuencode);
+ $self->debug("encoding? ", $encoding);
+ $self->debug("effective type? ", $ent->effective_type);
+ if ($self->extract_uuencode and
+ ($encoding =~ /^(7bit|8bit|binary)\Z/) and
+ ($ent->effective_type =~ m{^text/plain\Z})) {
+
+ ### Hunt for it:
+ my $uu_ent = eval { $self->hunt_for_uuencode($ENCODED, $ent) };
+ if ($uu_ent) { ### snark
+ %$ent = %$uu_ent;
+ return 1;
+ }
+ else { ### boojum
+ $self->whine("while hunting for uuencode: $@");
+ $ENCODED->seek(0,0);
+ }
+ }
+
+ ### Decode and save the body (using the decoder):
+ my $DECODED = $body->open("w") || die "$ME: body not opened: $!\n";
+
+ my $bm = benchmark {
+ eval { $decoder->decode($ENCODED, $DECODED); };
+ $@ and $self->error($@);
+ };
+ $self->debug("t decode: $bm");
+
+ $DECODED->close;
+
+ } else {
+ ### No decoding, copy the data as is into the body object
+ my $HANDLE = $body->open("w") || die "$ME: body not opened: $!\n";
+ my $buf;
+ $HANDLE->print($buf) while ($ENCODED->read($buf, 2048));
+ $HANDLE->close;
+ $body->is_encoded(1);
}
-
- ### Open a new bodyhandle for outputting the data:
- my $body = $self->new_body_for($head) || die "$ME: no body\n"; # gotta die
- $body->binmode(1) unless textual_type($ent->effective_type);
- ### Decode and save the body (using the decoder):
- my $DECODED = $body->open("w") || die "$ME: body not opened: $!\n";
- my $bm = benchmark {
- eval { $decoder->decode($ENCODED, $DECODED); };
- $@ and $self->error($@);
- };
- $self->debug("t decode: $bm");
- $DECODED->close;
-
### Success! Remember where we put stuff:
$ent->bodyhandle($body);
