keys/tripe-keys.in: Compare configuration files properly when updating.

[tripe] / server / tripe.8.in

diff --git a/server/tripe.8.in b/server/tripe.8.in
index ebbfc7904ce0c009704a198fd068d168d704db33..854b3a0a78672ec7febd0acf5e55c3ee564cf310 100644 (file)
--- a/server/tripe.8.in
+++ b/server/tripe.8.in
@@ -361,8 +361,13 @@ mode, designed by Bellare, Canetti and Krawczyk).  These can all be
 overridden by setting attributes on your private key, as follows.
 .TP
 .B bulk
 overridden by setting attributes on your private key, as follows.
 .TP
 .B bulk

-Names the bulk-crypto transform to use.  Currently the only choice is
-.BR v0 .
+Names the bulk-crypto transform to use.  See below.
+.TP
+.B blkc
+Names a block cipher, used by some bulk-crypto transforms (e.g.,
+.BR iiv ).  The default is to use the block cipher underlying the chosen
+.BR cipher ,
+if any.

 .TP
 .B cipher
 Names the symmetric encryption scheme to use.  The default is
 .TP
 .B cipher
 Names the symmetric encryption scheme to use.  The default is


@@ -384,6 +389,26 @@ at half the underlying hash function's output length.
 A `mask-generation function', used in the key-exchange.  The default is
 .IB hash \-mgf
 and there's no good reason to change it.
 A `mask-generation function', used in the key-exchange.  The default is
 .IB hash \-mgf
 and there's no good reason to change it.

+.PP
+The available bulk-crypto transforms are as follows.
+.TP
+.B v0
+Originally this was the only transform available.  It's a standard
+generic composition of a CPA-secure symmetric encryption scheme with a
+MAC; initialization vectors for symmetric encryption are chosen at
+random and included explicitly in the cryptogram.
+.TP
+.B iiv
+A newer `implicit-IV' transform.  Rather than having an explicit random
+IV, the IV is computed from the sequence number using a block cipher.
+This has two advantages over the
+.B v0
+transform.  Firstly, it adds less overhead to encrypted messages
+(because the IV no longer needs to be sent explicitly).  Secondly, and
+more significantly, the transform is entirely deterministic, so (a) it
+doesn't need the (possibly slow) random number generator, and (b) it
+closes a kleptographic channel, over which a compromised implementation
+could leak secret information to a third party.

 .SS "Using SLIP interfaces"
 Though not for the faint of heart, it is possible to get
 .B tripe
 .SS "Using SLIP interfaces"
 Though not for the faint of heart, it is possible to get
 .B tripe