Re: [ietf-822] A permission to re-sign header
Alessandro Vesely <vesely@tana.it> Sat, 19 April 2014 09:39 UTC
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Date: Sat, 19 Apr 2014 11:39:20 +0200
From: Alessandro Vesely <vesely@tana.it>
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Subject: Re: [ietf-822] A permission to re-sign header
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On Fri 18/Apr/2014 14:37:21 +0200 John Levine wrote: >> Even with the local part (marissam) an M-R is not really hard to >> forge, otherwise DKIM-Signature wouldn't have had to include all the >> other tags. If we worry about replay attacks, we can enhance M-R so >> that it includes them too. For example, we could make M-R exactly >> like a regular DKIM-Signature, except that it would be a very very >> weak one, something that the MLM won't break. > > BTDT. If we could invent a weak signature that the MLM won't break, > we wouldn't have this problem. The M-R token is signed so it should > be impossible to forge, and we don't expect anyone to change it in > transit. I reckon M-R is equivalent to a DKIM-Signature having h=From:To; l=0; assuming "From: marissam@yahoo.com" and "To: r=ietf.org". Correct? The equivalent signature is even weaker than it needs to. IME, the only problem is that some sites (e.g. netease) have a local policy whereby they discard weak signatures. (Their DMARC reports say "DKIM-Signature could not parse or has bad tags/values".) Ale
- [ietf-822] A permission to re-sign header John Levine
- Re: [ietf-822] A permission to re-sign header Alessandro Vesely
- Re: [ietf-822] A permission to re-sign header John Levine
- Re: [ietf-822] A permission to re-sign header Hector Santos
- Re: [ietf-822] A permission to re-sign header Murray S. Kucherawy
- Re: [ietf-822] A permission to re-sign header John R Levine
- Re: [ietf-822] A permission to re-sign header Murray S. Kucherawy
- Re: [ietf-822] A permission to re-sign header John R Levine
- Re: [ietf-822] A permission to re-sign header Pete Resnick
- Re: [ietf-822] A permission to re-sign header Pete Resnick
- Re: [ietf-822] A permission to re-sign header John R Levine
- Re: [ietf-822] A permission to re-sign header Pete Resnick
- Re: [ietf-822] A permission to re-sign header John R Levine
- Re: [ietf-822] A permission to re-sign header Alessandro Vesely
- Re: [ietf-822] A permission to re-sign header Michael Richardson
- Re: [ietf-822] A permission to re-sign header Michael Richardson
- Re: [ietf-822] A permission to re-sign header Theodore Ts'o
- Re: [ietf-822] A permission to re-sign header Pete Resnick
- Re: [ietf-822] A permission to re-sign header Miles Fidelman
- Re: [ietf-822] A permission to re-sign header John Levine
- Re: [ietf-822] one can re-sign without a permissi… Ned Freed
- Re: [ietf-822] one can re-sign without a permissi… Alessandro Vesely
- Re: [ietf-822] A permission to re-sign header Ned Freed
- Re: [ietf-822] A permission to re-sign header Alessandro Vesely
- Re: [ietf-822] A permission to re-sign header Paul Smith
- Re: [ietf-822] don't need a permission to re-sign… John Levine
- Re: [ietf-822] don't need a permission to re-sign… Ned Freed
- Re: [ietf-822] don't need a permission to re-sign… John R Levine
- Re: [ietf-822] don't need a permission to re-sign… Ned Freed
- Re: [ietf-822] one can re-sign without a permissi… Alessandro Vesely
- Re: [ietf-822] one can re-sign without a permissi… Ned Freed
- Re: [ietf-822] one can re-sign without a permissi… Pete Resnick
- Re: [ietf-822] one can re-sign without a permissi… Douglas Otis
- [ietf-822] We need a DKIM Policy Working Group Hector Santos
- Re: [ietf-822] We need a DKIM Policy Working Group S Moonesamy
- Re: [ietf-822] one can re-sign without a permissi… John Levine
- Re: [ietf-822] one can re-sign without a permissi… John Levine
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Miles Fidelman
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Alessandro Vesely
- Re: [ietf-822] one can re-sign without a permissi… Douglas Otis
- Re: [ietf-822] one can re-sign without a permissi… Pete Resnick
- Re: [ietf-822] one can re-sign without a permissi… Alessandro Vesely
- Re: [ietf-822] one can re-sign without a permissi… Paul Smith
- Re: [ietf-822] one can re-sign without a permissi… John R Levine
- Re: [ietf-822] one can re-sign without a permissi… Hector Santos
- Re: [ietf-822] one can re-sign without a permissi… Douglas Otis
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Alessandro Vesely
- Re: [ietf-822] one can re-sign without a permissi… Hector Santos
- [ietf-822] WSJ/gmail/ML, was a permission to... Alessandro Vesely
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… John R Levine
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Paul Smith
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Rolf E. Sonneveld
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Hector Santos
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Michael Richardson
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Paul Smith
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Alessandro Vesely
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Miles Fidelman
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… John R Levine
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… John Levine
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Arnt Gulbrandsen
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… John Levine
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Ned Freed
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Dave Crocker
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Ned Freed
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… John R Levine
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… John R Levine
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Arnt Gulbrandsen
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Bart Schaefer
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Hector Santos
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… John Levine
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Michael Richardson
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Michael Richardson
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… John Levine
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Ned Freed
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Michael Richardson
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Michael Richardson
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Russ Allbery
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Brandon Long
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Brandon Long
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Arnt Gulbrandsen
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Alessandro Vesely
- Re: [ietf-822] one can re-sign without a permissi… Paul Smith
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Hector Santos
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… John R Levine
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Ned Freed
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… S Moonesamy
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Russ Allbery
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Hector Santos
- Re: [ietf-822] one can re-sign without a permissi… Brandon Long
- Re: [ietf-822] one can re-sign without a permissi… Murray S. Kucherawy
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Miles Fidelman
- Re: [ietf-822] one can re-sign without a permissi… John R Levine
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Ned Freed
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… S Moonesamy
- Re: [ietf-822] one can re-sign without a permissi… John Levine
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Miles Fidelman
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Scott Kitterman
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Russ Allbery
- Re: [ietf-822] one can re-sign without a permissi… Murray S. Kucherawy
- Re: [ietf-822] one can re-sign without a permissi… John R Levine
- Re: [ietf-822] one can re-sign without a permissi… Hector Santos
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… S Moonesamy
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Paul Smith
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Alessandro Vesely
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Miles Fidelman
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… John Levine
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… John Levine
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Brandon Long
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Brandon Long
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Russ Allbery
- [ietf-822] Aptness of DKIM for MLs Alessandro Vesely
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Alessandro Vesely
- Re: [ietf-822] Aptness of DKIM for MLs S Moonesamy
- Re: [ietf-822] Aptness of DKIM for MLs Alessandro Vesely
- Re: [ietf-822] Aptness of DKIM for MLs S Moonesamy
- Re: [ietf-822] Aptness of DKIM for MLs Hector Santos
- Re: [ietf-822] Aptness of DKIM for MLs Douglas Otis
- Re: [ietf-822] Aptness of DKIM for MLs Alessandro Vesely
- Re: [ietf-822] Aptness of DKIM for MLs Douglas Otis
- Re: [ietf-822] WSJ/gmail/ML, was a permission to.… Douglas Otis
- Re: [ietf-822] Aptness of DKIM for MLs Alessandro Vesely
- Re: [ietf-822] one can re-sign without a permissi… Douglas Otis