[Swan-dev] DCOOKIE on server causes STF_FAIL with <no reason>

[Paul Wouters 🔓]

Mostly cosmetic:

| busy mode on. received I1 without a valid dcookie
| send a dcookie and forget this state
packet from 2001:db8:11::ff:fe00:1700:500: sending unencrypted notification v2N_COOKIE to 2001:db8:11::ff:fe00:1700:500
| **emit ISAKMP Message:
|    initiator cookie:
|   8b a2 e3 9b  35 71 11 88
|    responder cookie:
|   00 00 00 00  00 00 00 00
|    next payload type: ISAKMP_NEXT_v2N
|    ISAKMP version: IKEv2 version 2.0 (rfc4306/rfc5996)
|    exchange type: ISAKMP_v2_SA_INIT
|    flags: ISAKMP_FLAG_v2_MSG_RESPONSE
|    message ID:  00 00 00 00
| Adding a v2N Payload
| ***emit IKEv2 Notify Payload:
|    next payload type: ISAKMP_NEXT_v2NONE
|    flags: none
|    Protocol ID: PROTO_RESERVED
|    SPI size: 0
|    Notify Message Type: v2N_COOKIE
| emitting 20 raw bytes of Notify data into IKEv2 Notify Payload
| Notify data  49 56 71 8d  bb 29 1e 32  14 83 fb cd  1c ff a8 45
| Notify data  b9 85 a0 71
| emitting length of IKEv2 Notify Payload: 28
| no IKE message padding required
| emitting length of ISAKMP Message: 56
| sending 56 bytes for send_v2_notification through eth1:500 to 2001:db8:11::ff:fe00:1700:500 (using #0)
|   8b a2 e3 9b  35 71 11 88  00 00 00 00  00 00 00 00
|   29 20 22 20  00 00 00 00  00 00 00 38  00 00 00 1c
|   00 00 40 06  49 56 71 8d  bb 29 1e 32  14 83 fb cd
|   1c ff a8 45  b9 85 a0 71
| complete v2 state transition from STATE_UNDEFINED with STF_FAIL
| state transition function for STATE_UNDEFINED failed: <no reason given>
| * processed 0 messages from cryptographic helpers
| next event EVENT_PENDING_DDNS in 48 seconds
| next event EVENT_PENDING_DDNS in 48 seconds

I guess STF_FAIL is okay, although it would probably be nice to have
"<no reason given>" changed for "sent dcookie" or something?

Paul