Editing Talk:1181: PGP

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Everybody below seems to have misread the comic.  It says nothing about 'verifying that the email is secure' or secret, or encrypted.  It says verifying that the email is '''AUTHENTIC'''.  This is a significant difference in meaning.[[Special:Contributions/24.70.188.179|24.70.188.179]] 15:55, 4 March 2013 (UTC)
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Everybody below seems to have misread the comic.  It says nothing about 'verifying that the email is secure' or secret, or encrypted.  It says verifying that the email is AUTHENTIC.  This is a significant difference in meaning.[[Special:Contributions/24.70.188.179|24.70.188.179]] 15:55, 4 March 2013 (UTC)
: I understood the same. I am probably the only nerd that use PGP. So if you receive a mail with that "heading" it's probably from me.[[Special:Contributions/83.42.5.246|83.42.5.246]] 09:20, 5 March 2013 (UTC)
 
: '''"AUTHENTIC" what?'''  Not to be too much of an engineer, but a confirmed/verified PGP signature only means that the contents have not been altered and the message was signed by the stated someone, but that 'stated someone' isn't necessarily the person whom you think it is.  To map a real person to a digital signature PGP uses the "Web of Trust" model that relies upon the signer and reader trusting many third parties and thus building trust-links (a web)...  rather than a central authority figure who issues trust to both users (the PKI model).--[[User:Sweerek|Sweerek]] ([[User talk:Sweerek|talk]]) 15:28, 2 April 2013 (UTC)
 
::Or you could go see them in person and have them print out their signature. [[User:Jacky720|That's right, Jacky720 just signed this]] ([[User talk:Jacky720|talk]] | [[Special:Contributions/Jacky720|contribs]]) 19:22, 2 July 2017 (UTC)
 
  
 
I don't really understand what's funny about this comic. [[Special:Contributions/76.106.251.87|76.106.251.87]] 05:53, 4 March 2013 (UTC)
 
I don't really understand what's funny about this comic. [[Special:Contributions/76.106.251.87|76.106.251.87]] 05:53, 4 March 2013 (UTC)
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I think merely the fact that PGP is in the email itself suggests the sender of the email is probably just a big nerd and therefore can be trusted. {{unsigned|153.90.91.1}}
 
I think merely the fact that PGP is in the email itself suggests the sender of the email is probably just a big nerd and therefore can be trusted. {{unsigned|153.90.91.1}}
: You are the type of person that the comic is making fun of. You assume it's safe and don't bother to verify it. [[Special:Contributions/108.162.212.18|108.162.212.18]] 16:37, 28 June 2014 (UTC)
 
  
 
Isn't it that those markers could very simply just have been typed in, rather than being part of the decryption system? [[User:DonGoat|DonGoat]] ([[User talk:DonGoat|talk]]) 07:41, 4 March 2013 (UTC)
 
Isn't it that those markers could very simply just have been typed in, rather than being part of the decryption system? [[User:DonGoat|DonGoat]] ([[User talk:DonGoat|talk]]) 07:41, 4 March 2013 (UTC)
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There is an interesting comparison to do with regular handwritten signature, as this is exactly how people check the authenticity of a handwritten signed document: check for a signature. If there is one, and if there is, even if you never saw a sample of that signature, trust it. However, as with cryptographic signature with an unknown key, this does rely one something: the fact that it is forbidden, and punishable, to counterfeit one's signature, even if it is badly done (as in: write a random signature, hoping that the recipient does not know the real signature of the alleged author). -- [[User:Elessar|Elessar]] ([[User talk:Elessar|talk]]) 09:02, 4 March 2013 (UTC)
 
There is an interesting comparison to do with regular handwritten signature, as this is exactly how people check the authenticity of a handwritten signed document: check for a signature. If there is one, and if there is, even if you never saw a sample of that signature, trust it. However, as with cryptographic signature with an unknown key, this does rely one something: the fact that it is forbidden, and punishable, to counterfeit one's signature, even if it is badly done (as in: write a random signature, hoping that the recipient does not know the real signature of the alleged author). -- [[User:Elessar|Elessar]] ([[User talk:Elessar|talk]]) 09:02, 4 March 2013 (UTC)
:Speaking of not checking handwritten signatures: http://www.zug.com/pranks/credit/ -- [[Special:Contributions/24.72.82.182|24.72.82.182]] 21:45, 4 March 2013 (UTC)
 
  
 
I agree with the commenters above me and I think the explanation goes into the wrong direction. This cartoon has nothing to do with encryption, it's only about (cryptographically) signing an e-mail. PGP can do both, but whilst signing is done using your own secret PGP key, for encryption you must have the public key of the recipient, so they must already know how to use PGP (or GnuPG) and have it installed. The cartoon is about people who either do not have PGP installed in their e-mail program or are using a web mailer (like many) that cannot handle cryptographically signed messages. For them, the signature is useless, unless they believe that the mere existence of a signature is a proof that the message is authentic.  
 
I agree with the commenters above me and I think the explanation goes into the wrong direction. This cartoon has nothing to do with encryption, it's only about (cryptographically) signing an e-mail. PGP can do both, but whilst signing is done using your own secret PGP key, for encryption you must have the public key of the recipient, so they must already know how to use PGP (or GnuPG) and have it installed. The cartoon is about people who either do not have PGP installed in their e-mail program or are using a web mailer (like many) that cannot handle cryptographically signed messages. For them, the signature is useless, unless they believe that the mere existence of a signature is a proof that the message is authentic.  
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:You may be confusing "ASCII armored" (which in OpenPGP speak is "a BASE64-encoded version of the signature or encrypted text") with the encoding of the actual data (which may also be BASE64, or it may be Quoted-Nonprintable, or it may be actual plain-text ASCII). This separation line signals that signature will be at the end, and that the mail will not be encoded in PGP-MIME, which pretty much requires that the signature is ASCII armored.[[Special:Contributions/195.144.91.202|195.144.91.202]] 12:03, 4 March 2013 (UTC)
 
:You may be confusing "ASCII armored" (which in OpenPGP speak is "a BASE64-encoded version of the signature or encrypted text") with the encoding of the actual data (which may also be BASE64, or it may be Quoted-Nonprintable, or it may be actual plain-text ASCII). This separation line signals that signature will be at the end, and that the mail will not be encoded in PGP-MIME, which pretty much requires that the signature is ASCII armored.[[Special:Contributions/195.144.91.202|195.144.91.202]] 12:03, 4 March 2013 (UTC)
 
::At the time of my comment, the explanation said: ''»[...] Randall suggests that if you just look for "Begin PGP Signed Message" in the message, the assumption that the message is encrypted is "Pretty Good." This holds true as one of the RFC4880-devised plaintext headers '''for messages with ASCII armor''' is exactly this text«'' (emphasis by me), whereas RFC 4880 defines in section "Cleartext Signature Framework" that this header is used for ''cleartext'' messages, i.e. explicitly ''without'' ASCII armor. The explanation was changed shortly afterwards, so my comment was outdated and apparently confusing. [[Special:Contributions/128.7.3.55|128.7.3.55]] 11:48, 7 March 2013 (UTC)
 
  
 
:I also agree that the explanation doesn't really explain the point. PGP does not only provide encryption (which is in some sense privacy), but also authentication. If I publish my public key, anyone can use it to verify an email I signed with my private key. The joke is about what really happens. The text says: "If you find a header, this indicates a signed message. You are pretty safe if you assume the mail is authentic." This is funny, because email signatures are still so uncommon that there actually is no need to fake it. If you fake an email, why faking a signature? Just don't sign it. The image text goes one step further saying that you're safer when you look at the bottom of the mail and look for some weird random characters. This is what the actual signature looks like, but of course, the only way to really authenticate the mail is to use the sender's public key to verify that the random characters are a real signature. --[[User:BKA|BKA]] ([[User talk:BKA|talk]]) 12:19, 4 March 2013 (UTC)
 
:I also agree that the explanation doesn't really explain the point. PGP does not only provide encryption (which is in some sense privacy), but also authentication. If I publish my public key, anyone can use it to verify an email I signed with my private key. The joke is about what really happens. The text says: "If you find a header, this indicates a signed message. You are pretty safe if you assume the mail is authentic." This is funny, because email signatures are still so uncommon that there actually is no need to fake it. If you fake an email, why faking a signature? Just don't sign it. The image text goes one step further saying that you're safer when you look at the bottom of the mail and look for some weird random characters. This is what the actual signature looks like, but of course, the only way to really authenticate the mail is to use the sender's public key to verify that the random characters are a real signature. --[[User:BKA|BKA]] ([[User talk:BKA|talk]]) 12:19, 4 March 2013 (UTC)
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Incidentally nearly EVERYONE has seen a public key verified message.  Visit any https website, and odds are the web browser not only established a secure channel through asymmetric (public key) encryption, but also verifies the owner of the 'site by checking with places like VeriSign.  How many people here have visited their own HTTPS 'site, (while playing around with a server, for instance,) and had their browser pop up a warning about the 'site being unverified? [[Special:Contributions/156.110.38.82|156.110.38.82]] 14:50, 4 March 2013 (UTC)
 
Incidentally nearly EVERYONE has seen a public key verified message.  Visit any https website, and odds are the web browser not only established a secure channel through asymmetric (public key) encryption, but also verifies the owner of the 'site by checking with places like VeriSign.  How many people here have visited their own HTTPS 'site, (while playing around with a server, for instance,) and had their browser pop up a warning about the 'site being unverified? [[Special:Contributions/156.110.38.82|156.110.38.82]] 14:50, 4 March 2013 (UTC)
 
As several others have noted, PGP can be used to encrypt and/or authenticate a message. I'd argue that the latter function is of little utility in the real world, as it solves a problem that few people have (the system itself dates to when e-mail was used very differently, and the expected future use case didn't exactly go as we all imagined). Security nerds would rarely need to authenticate anything that is otherwise unimportant enough to not bother to encrypt; typical end-users often can't even recognize obvious phishes, so unless their OS transparently refused to even display an email from a sender whose key was not in the recipients' keyring (ignoring all the complexity putting it in there entails) they would treat all emails as authentic anyway...which is what they do. E-mail was never designed for security, and nowadays the majority of it is spam, legit-spam, virtual receipts, and the like; there is so much noise now that most people who need secure communications have other vectors for such. <br> [TL;DR: if you both need and know how to use PGP authentication of plaintext e-mail for important communication, you probably don't send those important things via plaintext e-mail.] [[Special:Contributions/173.161.183.129|173.161.183.129]] 18:49, 4 March 2013 (UTC)
 
 
Also, Randall's comment that the presence of a signature does not necessarily authenticate the message is reminiscent of [[1121: Identity]]. --[[Special:Contributions/213.151.48.139|213.151.48.139]] 12:13, 6 March 2013 (UTC)
 
 
Hmmm... my take, and I thought I saw someone else hint at this above, is that the PGP decoration leads the ''unsophisticated'' reader into a ''false'' sense of security.  It's akin to that severe-looking envelope marked "For Official Business Only" but coming from some mass mailer making it seem like their solicitation is in fact some official governmental communication.  "It's got ''that'' on the cover, it ''must'' be important.  I better find out what it is..." Voila.  Mission accomplished. -- [[User:IronyChef|IronyChef]] ([[User talk:IronyChef|talk]]) 16:25, 9 March 2013 (UTC)
 
 
What would have been really funny is if the email content showed an attempt at [http://en.wikipedia.org/wiki/Nigerian_scam Nigerian Scam]. [[User:Abhaysk|Abhaysk]] ([[User talk:Abhaysk|talk]]) 01:06, 12 March 2013 (UTC)
 
:"As several others have noted, PGP can be used to encrypt and/or authenticate a message. I'd argue that the latter function is of little utility in the real world" :I'd argue the opposite, spoofing an email is trivial, reading someone elses email is somewhat harder. Having a policy of only performing certain actions based on signed mails from known keys makes a lot of sense. [[Special:Contributions/141.101.98.51|141.101.98.51]] 13:36, 18 March 2014 (UTC)
 
 
The best use of this is to purposely send emails with invalid signatures.  No one will ever notice since no one uses PGP.  But if someone ever tries to hold you accountable for an email you sent, you can explain how PGP authentication works and prove that your signature is invalid. [[Special:Contributions/108.162.216.190|108.162.216.190]] 13:49, 11 March 2015 (UTC)
 

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