[Swan-dev] please fix ikev1-algo-05-3des-sha2

[D. Hugh Redelmeier]

Pluto log on east says:

"westnet-eastnet-ipv4-psk-ikev1" #1: STATE_MAIN_R3: sent MR3, ISAKMP SA established {auth=PRESHARED_KEY cipher=aes_256 integ=sha2_256 group=MODP2048}
"westnet-eastnet-ipv4-psk-ikev1" #1: the peer proposed: 192.0.2.0/24:0/0 -> 192.0.1.0/24:0/0
"westnet-eastnet-ipv4-psk-ikev1" #2: IPsec encryption transform rejected: 3DES_CBC key_len 0 is incorrect
"westnet-eastnet-ipv4-psk-ikev1" #2: sending encrypted notification BAD_PROPOSAL_SYNTAX to 192.1.2.45:500

I think that the test is broken.  But it might be that Pluto is
broken.  I guess that this is something that Andrew is best equipped
to fix.

Bonus points (not just for Andrew):

(1) I assume that this notification was encrypted.  But nothing about a
notification shows up on west.console.diff.

Should we not report authenticated notifications to whack?  It is
reported in Pluto's log on west:

"westnet-eastnet-ipv4-psk-ikev1" #1: ignoring informational payload BAD_PROPOSAL_SYNTAX, msgid=00000000, length=12
| ISAKMP Notification Payload
|   00 00 00 0c  00 00 00 01  01 00 00 0f

(3) the message should make clear whether the informational payload
was authenticated.

(3) It would be nice of Pluto to report a decoded version of this
payload to the user.  That would help the user understand the problem.

(4) It would probably be smart not to keep resending the same message
when it is so very likely that the outcome will be identical.
This isn't a bug so it isn't very important.