On Sat, Jun 30, 2007 at 02:42:49PM +0530, Hardeep Singh wrote: > On 6/27/07, David Shaw <[EMAIL PROTECTED]> wrote: > > On Mon, Jun 25, 2007 at 02:06:55PM +0200, Werner Koch wrote: > > > On Sun, 24 Jun 2007 12:07, [EMAIL PROTECTED] said: > > > > > > > If someone sends me an ASCII armoured file with some signed text, can > > > > I convert it into cleartext sign so that I can display it to people > > > > without GPG also? > > > > > > In general not because the canonicalization is different between the > > > formats. A conversion would break the signature. > > > > Interestingly enough, while you can't always go from a signed file to > > a clearsigned file, you can safely do the opposite of what the > > original poster asked: converting from cleartext to a signed file > > (armored or not) is possible. > > > > (I'm not sure when someone would want to do this, but...)
> How do we do that? You grab the signature from the clearsigned file, convert it to binary form, grab the text from the clearsigned file, package it inside a plaintext packet, and then just glue the two together. Something like this: 1. gpg --output text_part clearsigned_file 2. gpg --output sig_part.gpg --dearmor (now paste in the signature from the clearsigned file) ^D 3. Edit text_part and remove any whitespace at the end of each line, then remove the LAST (and only the last) message separator (CR, LF, etc). 4. gpg -z0 --textmode --store text_part 5. cat sig_part.gpg text_part.gpg > my_new_file.gpg Step 3 is the tricky bit, of course. Using a unix-ish system as an example, if the text file ends with "\n\n", you still only remove the last "\n". Step 5 makes a old-style signed file (you could make a new-style onepass signed file, but you'd need to create the onepass packet). It's an interesting side-effect of how the text canonicalization is done. The clearsigning rules are more strict than the regular signature rules, so it's possible to switch the packaging like this. David _______________________________________________ Gnupg-users mailing list Gnupg-users@gnupg.org http://lists.gnupg.org/mailman/listinfo/gnupg-users
