How to decrypt symmetric ciphertext without files?

[Dave U. Random]

I know how to get it done with files, that's easy.

What I want is to be able to use the command line to get gpg going,
paste the ciphertext and the pass-phrase in and get the plaintext
on screen.

I am not starting out with a file on my computer. I just have the
ciphertext available for pasting.

Sounds like it should be simple, but I'm not having luck with
trying to get it done. I've tried a bunch of different command line
combinations, but I must be missing something. Any suggestions?

[hymie!]

In our last episode, the evil Dr. Lacto had captured our hero,

Post by Dave U. Random
What I want is to be able to use the command line to get gpg going,
paste the ciphertext and the pass-phrase in and get the plaintext
on screen.

I assume you're referring to a Unix machine. There's a trick.

$ cat | gpg
<paste your text here>

You should be prompted for the passphrase. DO NOT TYPE IT.

Hit ctrl-D

There will be no obvious response. Now type your passphrase.

--hymie! http://lactose.homelinux.net/~hymie ***@lactose.homelinux.net
-------------------------------------------------------------------------------

[Nomen Nescio]

Post by hymie!
In our last episode, the evil Dr. Lacto had captured our hero,

Post by Dave U. Random
What I want is to be able to use the command line to get gpg going,
paste the ciphertext and the pass-phrase in and get the plaintext
on screen.

I assume you're referring to a Unix machine.

Actually, no. It's a Windows Vista box.

Post by hymie!
There's a trick.
$ cat | gpg
<paste your text here>
You should be prompted for the passphrase. DO NOT TYPE IT.
Hit ctrl-D
There will be no obvious response. Now type your passphrase.

There's a similar sequence of actions in Windows. I'm just not getting the combination right. I enter gpg -d<enter> and then if I enter the ciphertext I get the reply

gpg: encrypted with 1 passphrase
gpg: decryption failed: bad key

I never got to enter the key. If I just enter the key first I get
nohing, if I the enter the ciphertext I get the above again.

I'm clearly just missing some part of the proper sequence, but I've
looked and I can't find anything about how to do what I want.

[Arthur T.]

Post by Nomen Nescio
There's a similar sequence of actions in Windows. I'm just not getting the combination right. I enter gpg -d<enter> and then if I enter the ciphertext I get the reply
gpg: encrypted with 1 passphrase
gpg: decryption failed: bad key
I never got to enter the key. If I just enter the key first I get
nohing, if I the enter the ciphertext I get the above again.

Some trial and error got decrypting from the console to work for
me. See if it works for you, too:

The clipboard must have the ascii-armored encrypted text, BUT it
must NOT have the final line. Repeat, It MUST NOT have the line of
dashes surrounding END PGP MESSAGE.

Issue
gpg -d

Paste the encrypted text. If it does not include the final CRLF,
hit <Enter>. GPG replies something along the lines of:

gpg: CAST5 encrypted data
Enter passphrase:

Enter the password and hit <Enter>. GPG replies:

gpg: encrypted with 1 passphrase

Hit Ctrl-Z and <Enter>. The decrypted text should then show up.

When I had the whole thing (including that last line) in my
clipboard, I had the same problem that you did. But I noticed that
the GPG messages came out without that last line showing up. So I
experimented.

[Nomen Nescio]

Post by Arthur T.

Post by Nomen Nescio
There's a similar sequence of actions in Windows. I'm just not getting the combination right. I enter gpg -d<enter> and then if I enter the ciphertext I get the reply
gpg: encrypted with 1 passphrase
gpg: decryption failed: bad key
I never got to enter the key. If I just enter the key first I get
nohing, if I the enter the ciphertext I get the above again.

Some trial and error got decrypting from the console to work for
The clipboard must have the ascii-armored encrypted text, BUT it
must NOT have the final line. Repeat, It MUST NOT have the line of
dashes surrounding END PGP MESSAGE.
Issue
gpg -d
Paste the encrypted text. If it does not include the final CRLF,
gpg: CAST5 encrypted data
gpg: encrypted with 1 passphrase
Hit Ctrl-Z and <Enter>. The decrypted text should then show up.
When I had the whole thing (including that last line) in my
clipboard, I had the same problem that you did. But I noticed that
the GPG messages came out without that last line showing up. So I
experimented.

Bingo! Thank you Arthur T. That worked. I had tried all sorts of
combinatins but it had never ccurred to me to leave off the formal
ending of the gpg message. Thanks again.