-----BEGIN PGP SIGNED MESSAGE----- At 07:39 AM 1/29/96 -0500, Ted Garrett wrote:
-----BEGIN PGP SIGNED MESSAGE-----
I got a message in response to a request I made to someone for their public key. I wanted to check the signatures that they included with their posts to cypherpunks, but their key was not on the keyservers. The key they included was completely unsigned, and when I use it to validate their previous posts as well as the message they sent which included the key, the signatures come back as bad, the contents of the file changed. Names are appropriately withheld (I hope).
At this point, I think it would be appropriate to declare that I am the person Ted was communicating with, and the one he is referring to and (correctly, as I recall my own posts) quoting. I am, yes, a real newbie, and I appreciate the indirect lesson in "nettiquette" he is showing by not identifying my private email to him. I'm identifying myself for a number of reasons: 1. I REALLY am a newbie (at least to most of Internet, and common usage of PGP, etc.), and haven't learned much of the ways of Internet. (with a strange, short, early exception, which I will relate in another message if anybody has any interest in Internet history.) 2. I want to solve the problems Ted presumably correctly identified in my signing. (I use freebie Eudora, and WPGP, etc.) I only started signing my posts when I got a copy of WPGP by Gostl, and it made things much easier. 3. I did not want to make it difficult for him to fight off a potential MITM attack while, at the same time, complying with "nettiquette", especially seeing as how my key is not (yet) in any keyserver, which is obviously MY fault, not his! I want him to be able to point (and, repost, with my full permission) any messages allegedly from me that he receives by private email, so that others might check the signature too with their own software. This permission to him applies to any prior messages I've sent him, too, ideally so that anyone else can check the signature status against my sig. Ted may be right; there may be a MITM attack. More likely, it's a case of galloping NEWBIE-ITIS on my own part, sorry. Earlier, when I just began using WPGP to sign Eudora stuff, I was told that my signature didn't match. On the other hand, I was told by others that this is a common flaw of signing messages, having to do with line lengths. When I first started sending messages, I didn't use the "Wrap" selection of Eudora (under the EDIT selection), meaning that my lines were as long as the paragraphs were typed. Most people didn't seem to notice, I guess, because it took somebody a few weeks to eventually complain. After that, I RTFM'd and adopted the practice of WRAPping my paragraphs to limit their length to "reasonable" values. (although I would appreciate somebody explaining to me why this DAMN EUDORA can't seem to correctly re-wrap a paragraph after modification. Hell, Wordstar Version 3.0 for CP/M (shows you how long _I've_ been into computers!) reformatted paragraphs just fine back in 1982 on a 12.5 MHz Z-80 (ask me how I did this and I'll tell you a LONG story!) 3. Ted began to suspect a "MITM attack." While I'm a newbie, I'm well aware this is "man in the middle" and am aware of the potential (dangerous!) implications. Needless to say, I can't even say for certain that such an attack isn't happening. Yes, I am on no keyservers, yet, but I will try my best to follow his kind instructions and accomplish this feat. And yes, I am reminded that I need to sign my OWN public key, which (being a f______ newbie), I haven't even done yet! (This message will contain, however, BOTH my 1024-bit and 2047 bit public keys, unsigned, and I will sign the whole message with my 1024-bit key. I'd sign it with BOTH, but I don't know if WPGP will even do this. I'd sign a second copy with the 2047-bit key, except that would be wasting bandwidth.
As I understand the bcc: definition, only I and the first smtp server this message hits should know who it's to. I don't know if anyone else reading this mailing list needs this info, but just in case... here's my reply to the message.
At 10:03 PM 1/28/96 -0800, you wrote:
Sorry, I'm a newbie to Internet, and also the Internet usage of PGP. I just participated in a local keysigning meeting, so maybe my key will find its way to a server.
I wrote that.
Don't worry about being a 'newbie'. Everyone starts somewhere. However, your key will usually not 'find its way' to a server without you specifically sending it.
Thanks; I sorta assumed that, but until recently my usage of PGP was between me and my friends who knew me by face and voice, and who have my keys from hand-carried floppy disks that I gave them myself.
The keyserver I usually use is accessed by sending a mail message which fits the following format. As far as I know, all the keyservers use this format to add or update keys in their databases. You only have to send it to one keyserver, and it will propagate to all the others. I have indented the text so that no handlers decide to interpret it as a new message.
Okay, thanks for the details.
- - To: pgp-public-keys@pgp.iastate.edu - - Subject: ADD - - - - -----BEGIN PGP PUBLIC KEY BLOCK----- - - Version: 2.6.2 - - - - [key deleted to protect the innocent] - - - - -----END PGP PUBLIC KEY BLOCK-----
I'm sorry to have to admit that I don't even know how to do this! Newbie alert!
Again, I wrote that.
If you don't admit you don't know something, nobody will usually tell you how to do it. Also, you should sign your own key. That will make it harder to forge, I think.
Okay, up until now I've generally given out my key in messages, and signed the entire message with the key.
The reasons were spelled out in a couple of the web pages I read, but I've forgotten them. It has something to do with either a denial of service attack or a man in the middle attack, or both. The command to do this is:
Someday I'm gonna understand this stuff!
pgp -ks 0xHEXKEYID
Honestly, I've only just begun to use pgp myself. Also, you should add your e-mail address to the user-id of your key. The command to do so is:
pgp -ke 0xHEXKEYID
Again, much appreciated. I hate to RTFM. Lazy bum, I.
You will be asked if you wish to add a user id to the key. Say yes, and give it your e-mail address. What this does is it allows people who are using pgp-enabled mailers to directly encrypt messages to you without choosing your key manually.
The reason that I have not encrypted this message to you using the key you provided is that when I extracted the key and re-checked your message, the signature was no good. I've found that (using eudora) I must turn off the word wrap feature of my mailer to allow for good signed messages out. Of course, having said this, I'll probably not get a good signature on this message. Let me know if it signs ok.
I didn't check the signature of his message, admittedly. Guess I need to give him some feedback, huh?
Now, I have a question. Which attack(s) is/are a person vulnerable to when distributing an unsigned public key in the open? Could this actually be a complex man-in-the-middle attack? Am I paranoid?
Unfortunately, the more I learn about encryption, the more "paranoid" I get! Of course, I have a few more reasons than most, but... [I deleted Ted Garrett's signature. My own will follow my own two public keys.] My 1024-bit key. - -----BEGIN PGP PUBLIC KEY BLOCK----- Version: 2.6.2 mQCNAi1zvWcAAAEEAKmSqngLWK2N2gOJKPtjF9VCfSkXY+XUZBRCbbFU71uH/dLX C2Uq6wFS8alRgMc3rp90JnnJ/6eJqXwMjCunogwucWOaU7S/w+OwjOG9fUqsXIA6 2j25Wtjce65mbp0TKLAzwMb/P/Qq7BlclqhuKzfVBH7dIHnVAvqHVDBboB2dAAUR tBFKYW1lcyBEYWx0b24gQmVsbA== =G3LA - -----END PGP PUBLIC KEY BLOCK----- My 2047-bit key. - -----BEGIN PGP PUBLIC KEY BLOCK----- Version: 2.6.2 mQENAzDCFH4AAAEH/15sMvnnK1BIvLkxQsKwUHP7dKNFbKrQOtOoyLOFTk4/0Zlr gXkKw6NciDYaOKwW9dsIL3N3rjAlWtioQ/gg+5vMNoJOQXpp95mKBzpWYLeaB8MF Km6H/NGWISx5cz06NOGutWcaezO/S4xm8ay7W8HaZ4EmHQdXtSKIAL41PBQyyuhR wIKX+QwsAgKS1LALr9MuW7nXL6/h139QeNRAR+ubXyftoklFHC+HF+jcTTDuNjmU 4p7BEMp9cmYHh6WEYTZyOz5F8/8gtEbPA0IKsQH1LGdf+2APLqMdciuU8ALZA+ZM bbaBaxshqHbYfCQ8+ATCrBjsU0nO8RKjhSx91vkABRG0DUphbWVzIEQuIEJlbGw= =uncA - -----END PGP PUBLIC KEY BLOCK----- James Dalton Bell. Klaatu Burada Nikto Something is going to happen.... Something... Wonderful! -----BEGIN PGP SIGNATURE----- Version: 2.6.2 iQCVAwUBMQ1PZ/qHVDBboB2dAQE+AAP+MP5hM2j1Z3z+7cdZ/U12qH/uu6Dq2NEP LgKJ8Nm0idN7oiBZpYD2zuT22mhsIhCJzzmC3XIBiyX1AP4voDqrIwgLmvPgogcp Cr9p75xi2/UqV1mrYIWeHG4KJc+/x5V4PxeYg5iz0jjnLKN1mzmnjPRDqAOaaBhK 08MMgOkqxFs= =jU9M -----END PGP SIGNATURE-----