Site-to-Site Tunnel Between IOS Routers Using SEAL Sample Configuration

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Updated:January 13, 2008
Document ID:50880

Bias-Free Language

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Introduction

The Software Encryption Algorithm (SEAL) is an alternative algorithm to Data Encryption Standard (DES), Triple DES (3DES), and Advanced Encryption Standard (AES). SEAL encryption uses a 160-bit encryption key and has a lower impact to the CPU when compared to other software-based algorithms. This document illustrates how to configure a LAN-to-LAN (site-to-site) IPSec tunnel using SEAL.

Prerequisites

Requirements

There are no specific requirements for this document.

Components Used

The information in this document is based on these software and hardware versions:

  • Cisco 7200 series routers running Cisco IOS® Software Release 12.3(7)T

The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, make sure that you understand the potential impact of any command.

Conventions

For more information on document conventions, refer to Cisco Technical Tips Conventions.

Configure

In this section, you are presented with the information to configure the features described in this document.

Note: Use the Command Lookup Tool (registered customers only) to find more information on the commands used in this document.

Network Diagram

This document uses this network setup:

seal-rtr-tunnel-cnfg-1.gif

Configurations

This document uses these configurations:

Router 1 
version 12.3
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R1
!
boot-start-marker
boot-end-marker
!
!
clock timezone EST -5
no aaa new-model
ip subnet-zero
no ip domain lookup
!
!
ip cef
ip audit po max-events 100
no ftp-server write-enable
!
!
!
!

!--- ISAKMP policy configuration.

crypto isakmp policy 1
encr aes 256
hash md5
authentication pre-share
group 2
crypto isakmp key cisco123 address 10.10.10.2
!

!--- Define a transform set with SEAL. !--- If you use the esp-seal transform set and a crypto !--- accelerator is present, you receive a warning. !--- The configuration is accepted, but it !--- is ignored as long as the accelerator is present. !--- If you use the esp-seal transform set with either of !--- the other two limitations, you receive an error !--- and the configuration is rejected. 


crypto ipsec transform-set cisco esp-seal esp-sha-hmac
!

!--- Define a transform set with SEAL. 

crypto map cisco 10 ipsec-isakmp
set peer 10.10.10.2
set transform-set cisco
match address 100
!
!
!
interface Ethernet0/0
ip address 172.18.124.201 255.255.255.0
!

!--- Apply crypto-map to the public interface.
 
interface Ethernet1/0
ip address 10.10.10.1 255.255.255.0
crypto map cisco
!

ip classless
ip route 0.0.0.0 0.0.0.0 10.10.10.2

no ip http server
no ip http secure-server
!
!

!--- Access Control List (ACL) that defines the networks to encrypt.
 
access-list 100 permit ip 172.18.124.0 0.0.0.255 20.20.20.0 0.0.0.255
!
!
!
control-plane
!
!
line con 0
exec-timeout 0 0
line aux 0
line vty 0 4
password ww
login
!
!
end

Router 2 
version 12.3
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R2
!
boot-start-marker
boot-end-marker
!
!
clock timezone EST -5
no aaa new-model
ip subnet-zero
no ip domain lookup
!
!
ip cef
ip audit po max-events 100
no ftp-server write-enable
!
!
!
!

!--- ISAKMP policy configuration.

crypto isakmp policy 1
encr aes 256
hash md5
authentication pre-share
group 2
crypto isakmp key cisco123 address 10.10.10.1
!

!--- Define a transform set with SEAL. !--- If you use the esp-seal transform set and a crypto !--- accelerator is present, you receive a warning. !--- The configuration is accepted, but it !--- is ignored as long as the accelerator is present. !--- If you use the esp-seal transform set with either of !--- the other two limitations, you receive an error !--- and the configuration is rejected.
 

crypto ipsec transform-set cisco esp-seal esp-sha-hmac
!

!--- Define a transform set with SEAL.
 
crypto map cisco 10 ipsec-isakmp
set peer 10.10.10.1
set transform-set cisco
match address 100
!
!
!
!

!--- Apply crypto-map to the public interface. 

interface Ethernet0/0
ip address 10.10.10.2 255.255.255.0
crypto map cisco
!
interface Ethernet0/0
ip address 20.20.20.2 255.255.255.0
!
ip classless
ip route 0.0.0.0 0.0.0.0 10.10.10.1

no ip http server
no ip http secure-server
!
!

!--- ACL defines the networks to encrypt.
 
access-list 100 permit ip 20.20.20.0 0.0.0.255 172.18.124.0 0.0.0.255
!
!
!
control-plane
!
!
line con 0
exec-timeout 0 0
line aux 0
line vty 0 4
password ww
login
!
!
end

Verify

This section provides information you can use to confirm your configuration is working properly.

Certain show commands are supported by the Output Interpreter Tool (registered customers only) , which allows you to view an analysis of show command output.

  • show crypto map—Verifies the configuration on the router.

    This output is taken from Router 1.

    R1#show crypto map
Crypto Map "cisco" 10 ipsec-isakmp
Peer = 10.10.10.2
Extended IP access list 100
access-list 100 permit ip 172.18.124.0 0.0.0.255 20.20.20.0 0.0.0.255
Current peer: 10.10.10.2
Security association lifetime: 4608000 kilobytes/3600 seconds
PFS (Y/N): N
Transform sets={
cisco,
}
Interfaces using crypto map cisco:
Ethernet1/0

Troubleshoot

This section provides information you can use to troubleshoot your configuration.

Troubleshooting Commands

Certain show commands are supported by the Output Interpreter Tool (registered customers only) , which allows you to view an analysis of show command output.

Note: Before issuing debug commands, refer to Important Information on Debug Commands.

ISAMP and IPSec Debugs

  • show debugging—Displays information about the types of debugging that are enabled for your router.

R1#show debugging
Cryptographic Subsystem:
Crypto ISAKMP debugging is on
Crypto IPSEC debugging is on
 

R1#
*Apr 18 05:59:20.491: ISAKMP (0:0): received packet 
from 10.10.10.2 dport 500 sport 500 Global (N) NEW SA
*Apr 18 05:59:20.491: ISAKMP: Created a peer struct for 
10.10.10.2, peer port 500
*Apr 18 05:59:20.491: ISAKMP: Locking peer struct 0x25F0BD8, 
IKE refcount 1 for crypto_isakmp_process_block
*Apr 18 05:59:20.491: ISAKMP: local port 500, remote port 500
*Apr 18 05:59:20.519: insert sa successfully sa = 2398188
*Apr 18 05:59:20.519: ISAKMP:(0:1:SW:1):Input = IKE_MESG_FROM_PEER, IKE_MM_EXCH
*Apr 18 05:59:20.519: ISAKMP:(0:1:SW:1):Old State = IKE_READY 
New State = IKE_R_MM1

*Apr 18 05:59:20.579: ISAKMP:(0:1:SW:1): processing SA payload. message ID = 0
*Apr 18 05:59:20.579: ISAKMP:(0:1:SW:1): processing vendor id payload
*Apr 18 05:59:20.579: ISAKMP:(0:1:SW:1): vendor ID seems Unity/DPD 
 but major 157 mismatch
*Apr 18 05:59:20.579: ISAKMP:(0:1:SW:1): vendor ID is NAT-T v3
*Apr 18 05:59:20.579: ISAKMP:(0:1:SW:1): processing vendor id payload
*Apr 18 05:59:20.579: ISAKMP:(0:1:SW:1): vendor ID seems Unity/DPD 
 but major 123 mismatch
*Apr 18 05:59:20.579: ISAKMP:(0:1:SW:1): vendor ID is NAT-T v2
*Apr 18 05:59:20.579: ISAKMP: Looking for a matching key for 
 10.10.10.2 in default : success
*Apr 18 05:59:20.579: ISAKMP:(0:1:SW:1):found peer pre-shared key 
 matching 10.10.10.2
*Apr 18 05:59:20.579: ISAKMP:(0:1:SW:1): local preshared key found
*Apr 18 05:59:20.579: ISAKMP : Scanning profiles for xauth ...
*Apr 18 05:59:20.579: ISAKMP:(0:1:SW:1):Checking ISAKMP transform 1 
 against priority 1 policy
*Apr 18 05:59:20.579: ISAKMP: encryption AES-CBC
*Apr 18 05:59:20.579: ISAKMP: keylength of 256
*Apr 18 05:59:20.579: ISAKMP: hash MD5
*Apr 18 05:59:20.579: ISAKMP: default group 2
*Apr 18 05:59:20.579: ISAKMP: auth pre-share
*Apr 18 05:59:20.579: ISAKMP: life type in seconds
*Apr 18 05:59:20.579: ISAKMP: life duration (VPI) of 0x0 0x1 0x51 0x80
*Apr 18 05:59:20.579: ISAKMP:(0:1:SW:1):atts are acceptable. Next payload is 0
*Apr 18 05:59:20.579: ISAKMP:(0:1:SW:1): processing vendor id payload
*Apr 18 05:59:20.579: ISAKMP:(0:1:SW:1): vendor ID seems Unity/DPD 
 but major 157 mismatch
*Apr 18 05:59:20.579: ISAKMP:(0:1:SW:1): vendor ID is NAT-T v3
*Apr 18 05:59:20.579: ISAKMP:(0:1:SW:1): processing vendor id payload
*Apr 18 05:59:20.579: ISAKMP:(0:1:SW:1): vendor ID seems Unity/DPD 
 but major 123 mismatch
*Apr 18 05:59:20.579: ISAKMP:(0:1:SW:1): vendor ID is NAT-T v2
*Apr 18 05:59:20.579: ISAKMP:(0:1:SW:1):Input = IKE_MESG_INTERNAL, 
 IKE_PROCESS_MAIN_MODE
*Apr 18 05:59:20.579: ISAKMP:(0:1:SW:1):Old State = IKE_R_MM1 New 
 State = IKE_R_MM1

*Apr 18 05:59:20.619: ISAKMP:(0:1:SW:1): constructed NAT-T vendor-03 ID
*Apr 18 05:59:20.619: ISAKMP:(0:1:SW:1): sending packet to 10.10.10.2 
 my_port 500 peer_port 500 (R) MM_SA_SETUP
*Apr 18 05:59:20.619: ISAKMP:(0:1:SW:1):Input = IKE_MESG_INTERNAL, 
 IKE_PROCESS_COMPLETE
*Apr 18 05:59:20.619: ISAKMP:(0:1:SW:1):Old State = IKE_R_MM1 New 
 State = IKE_R_MM2

*Apr 18 05:59:20.911: ISAKMP (0:134217729): received packet from 
 10.10.10.2 dport 500 sport 500 Global (R) MM_SA_SETUP
*Apr 18 05:59:20.911: ISAKMP:(0:1:SW:1):Input = IKE_MESG_FROM_PEER, 
 IKE_MM_EXCH
*Apr 18 05:59:20.911: ISAKMP:(0:1:SW:1):Old State = IKE_R_MM2 
 New State = IKE_R_MM3

*Apr 18 05:59:20.939: ISAKMP:(0:1:SW:1): processing KE payload. message ID = 0
*Apr 18 05:59:20.939: ISAKMP:(0:1:SW:1): processing NONCE 
 payload. message ID = 0
*Apr 18 05:59:20.991: ISAKMP: Looking for a matching key for 
 10.10.10.2 in default : success
*Apr 18 05:59:20.991: ISAKMP:(0:1:SW:1):found peer pre-shared 
 key matching 10.10.10.2
*Apr 18 05:59:20.991: ISAKMP:(0:1:SW:1):SKEYID state generated
*Apr 18 05:59:20.991: ISAKMP:(0:1:SW:1): processing vendor id payload
*Apr 18 05:59:20.991: ISAKMP:(0:1:SW:1): vendor ID is Unity
*Apr 18 05:59:20.991: ISAKMP:(0:1:SW:1): processing vendor id payload
*Apr 18 05:59:20.991: ISAKMP:(0:1:SW:1): vendor ID is DPD
*Apr 18 05:59:20.991: ISAKMP:(0:1:SW:1): processing vendor id payload
*Apr 18 05:59:20.991: ISAKMP:(0:1:SW:1): speaking to another IOS box!
*Apr 18 05:59:20.991: ISAKMP:received payload type 17
*Apr 18 05:59:20.991: ISAKMP:received payload type 17
*Apr 18 05:59:20.991: ISAKMP:(0:1:SW:1):Input = IKE_MESG_INTERNAL, 
 IKE_PROCESS_MAIN_MODE
*Apr 18 05:59:20.991: ISAKMP:(0:1:SW:1):Old State = IKE_R_MM3 New 
 State = IKE_R_MM3

*Apr 18 05:59:21.051: ISAKMP:(0:1:SW:1): sending packet to 
 10.10.10.2 my_port 500 peer_port 500 (R) MM_KEY_EXCH
*Apr 18 05:59:21.051: ISAKMP:(0:1:SW:1):Input = IKE_MESG_INTERNAL, 
 IKE_PROCESS_COMPLETE
*Apr 18 05:59:21.051: ISAKMP:(0:1:SW:1):Old State = IKE_R_MM3 
 New State = IKE_R_MM4

*Apr 18 05:59:21.279: ISAKMP (0:134217729): received packet 
 from 10.10.10.2 dport 500 sport 500 Global (R) MM_KEY_EXCH
*Apr 18 05:59:21.279: ISAKMP:(0:1:SW:1):Input = IKE_MESG_FROM_PEER, 
 IKE_MM_EXCH
*Apr 18 05:59:21.279: ISAKMP:(0:1:SW:1):Old State = IKE_R_MM4 
 New State = IKE_R_MM5

*Apr 18 05:59:21.311: ISAKMP:(0:1:SW:1): processing ID payload. message ID = 0
*Apr 18 05:59:21.311: ISAKMP (0:134217729): ID payload
next-payload : 8
type : 1
address : 10.10.10.2
protocol : 17
port : 500
length : 12
*Apr 18 05:59:21.311: ISAKMP:(0:1:SW:1):: peer matches *none* of the profiles
*Apr 18 05:59:21.311: ISAKMP:(0:1:SW:1): processing HASH 
 payload. message ID = 0
*Apr 18 05:59:21.311: ISAKMP:(0:1:SW:1): processing NOTIFY 
 INITIAL_CONTACT protocol 1
spi 0, message ID = 0, sa = 2398188
*Apr 18 05:59:21.311: ISAKMP:(0:1:SW:1):SA authentication status:
authenticated
*Apr 18 05:59:21.311: ISAKMP:(0:1:SW:1): Process initial contact,
bring down existing phase 1 and 2 SA's with local 10.10.10.1 
 remote 10.10.10.2 remote port 500
*Apr 18 05:59:21.311: ISAKMP:(0:1:SW:1):SA authentication status:
authenticated
*Apr 18 05:59:21.311: ISAKMP:(0:1:SW:1):SA has been authenticated 
 with 10.10.10.2
*Apr 18 05:59:21.311: ISAKMP: Trying to insert a peer 
 10.10.10.1/10.10.10.2/500/, and inserted successfully.
*Apr 18 05:59:21.311: ISAKMP:(0:1:SW:1):: peer matches 
 *none* of the profiles
*Apr 18 05:59:21.311: ISAKMP:(0:1:SW:1):Input = IKE_MESG_INTERNAL, 
 IKE_PROCESS_MAIN_MODE
*Apr 18 05:59:21.311: ISAKMP:(0:1:SW:1):Old State = 
 IKE_R_MM5 New State = IKE_R_MM5

*Apr 18 05:59:21.331: IPSEC(key_engine): got a queue event with 1 kei messages
*Apr 18 05:59:21.391: ISAKMP:(0:1:SW:1):SA is doing 
 pre-shared key authentication using id type ID_IPV4_ADDR
*Apr 18 05:59:21.391: ISAKMP (0:134217729): ID payload
next-payload : 8
type : 1
address : 10.10.10.1
protocol : 17
port : 500
length : 12
*Apr 18 05:59:21.391: ISAKMP:(0:1:SW:1):Total payload length: 12
*Apr 18 05:59:21.391: ISAKMP:(0:1:SW:1): sending packet to 
 10.10.10.2 my_port 500 peer_port 500 (R) MM_KEY_EXCH
*Apr 18 05:59:21.391: ISAKMP:(0:1:SW:1):Input = IKE_MESG_INTERNAL, 
 IKE_PROCESS_COMPLETE
*Apr 18 05:59:21.391: ISAKMP:(0:1:SW:1):Old State = IKE_R_MM5 
 New State = IKE_P1_COMPLETE

*Apr 18 05:59:21.439: ISAKMP:(0:1:SW:1):Input = IKE_MESG_INTERNAL, 
 IKE_PHASE1_COMPLETE
*Apr 18 05:59:21.439: ISAKMP:(0:1:SW:1):Old State = IKE_P1_COMPLETE 
 New State = IKE_P1_COMPLETE

*Apr 18 05:59:21.779: ISAKMP (0:134217729): received packet from 
 10.10.10.2 dport 500 sport 500 Global (R) QM_IDLE
*Apr 18 05:59:21.779: ISAKMP: set new node 1056009800 to QM_IDLE
*Apr 18 05:59:21.779: ISAKMP:(0:1:SW:1): processing HASH payload. 
 message ID = 1056009800
*Apr 18 05:59:21.779: ISAKMP:(0:1:SW:1): processing SA payload. 
 message ID = 1056009800
*Apr 18 05:59:21.779: ISAKMP:(0:1:SW:1):Checking IPSec proposal 1
*Apr 18 05:59:21.779: ISAKMP: transform 1, ESP_SEAL
*Apr 18 05:59:21.779: ISAKMP: attributes in transform:
*Apr 18 05:59:21.779: ISAKMP: encaps is 1 (Tunnel)
*Apr 18 05:59:21.779: ISAKMP: SA life type in seconds
*Apr 18 05:59:21.779: ISAKMP: SA life duration (basic) of 3600
*Apr 18 05:59:21.779: ISAKMP: SA life type in kilobytes
*Apr 18 05:59:21.779: ISAKMP: SA life duration (VPI) of 0x0 0x46 0x50 0x0
*Apr 18 05:59:21.779: ISAKMP: authenticator is HMAC-SHA
*Apr 18 05:59:21.779: ISAKMP:(0:1:SW:1):atts are acceptable.
*Apr 18 05:59:21.779: IPSEC(validate_proposal_request): proposal part #1,
(key eng. msg.) INBOUND local= 10.10.10.1, remote= 10.10.10.2,
local_proxy= 172.18.124.0/255.255.255.0/0/0 (type=4),
remote_proxy= 20.20.20.0/255.255.255.0/0/0 (type=4),
protocol= ESP, transform= esp-seal esp-sha-hmac (Tunnel),
lifedur= 0s and 0kb,
spi= 0x0(0), conn_id= 0, keysize= 0, flags= 0x2
*Apr 18 05:59:21.779: IPSEC(kei_proxy): head = cisco, 
map->ivrf = , kei->ivrf =
*Apr 18 05:59:21.779: ISAKMP:(0:1:SW:1): processing NONCE 
payload. message ID = 1056009800
*Apr 18 05:59:21.779: ISAKMP:(0:1:SW:1): processing ID 
payload. message ID = 1056009800
*Apr 18 05:59:21.779: ISAKMP:(0:1:SW:1): processing ID 
payload. message ID = 1056009800
*Apr 18 05:59:21.779: ISAKMP:(0:1:SW:1): asking for 1 spis from ipsec
*Apr 18 05:59:21.779: ISAKMP:(0:1:SW:1):Node 1056009800, 
Input = IKE_MESG_FROM_PEER, IKE_QM_EXCH
*Apr 18 05:59:21.779: ISAKMP:(0:1:SW:1):Old State = 
IKE_QM_READY New State = IKE_QM_SPI_STARVE
*Apr 18 05:59:21.799: IPSEC(key_engine): got a queue event with 1 kei messages
*Apr 18 05:59:21.799: IPSEC(spi_response): getting spi 3711321544 for SA
from 10.10.10.1 to 10.10.10.2 for prot 3
*Apr 18 05:59:21.811: ISAKMP: received ke message (2/1)
*Apr 18 05:59:22.079: IPSec: Flow_switching Allocated flow 
for flow_id 134217729
*Apr 18 05:59:22.079: IPSec: Flow_switching Allocated flow 
for flow_id 134217730
*Apr 18 05:59:22.199: %CRYPTO-5-SESSION_STATUS: Crypto tunnel 
 is UP . Peer 10.10.10.2:500 Id: 10.10.10.2
*Apr 18 05:59:22.199: ISAKMP: Locking peer struct 0x25F0BD8, 
IPSEC refcount 1 for for stuff_ke
*Apr 18 05:59:22.199: ISAKMP:(0:1:SW:1): Creating IPSec SAs
*Apr 18 05:59:22.199: inbound SA from 10.10.10.2 to 10.10.10.1 (f/i) 0/ 0
(proxy 20.20.20.0 to 172.18.124.0)
*Apr 18 05:59:22.199: has spi 0xDD3645C8 and conn_id 2000 and flags 2
*Apr 18 05:59:22.199: lifetime of 3600 seconds
*Apr 18 05:59:22.199: lifetime of 4608000 kilobytes
*Apr 18 05:59:22.199: has client flags 0x0
*Apr 18 05:59:22.199: outbound SA from 10.10.10.1 to 10.10.10.2 (f/i) 0/0
 (proxy 172.18.124.0 to 20.20.20.0)
*Apr 18 05:59:22.199: has spi 1918479069 and conn_id 2001 and flags A
*Apr 18 05:59:22.199: lifetime of 3600 seconds
*Apr 18 05:59:22.199: lifetime of 4608000 kilobytes
*Apr 18 05:59:22.199: has client flags 0x0
*Apr 18 05:59:22.199: ISAKMP:(0:1:SW:1): sending packet to 
10.10.10.2 my_port 500 peer_port 500 (R) QM_IDLE
*Apr 18 05:59:22.199: ISAKMP:(0:1:SW:1):Node 1056009800, 
 Input = IKE_MESG_FROM_IPSEC, IKE_SPI_REPLY
*Apr 18 05:59:22.199: ISAKMP:(0:1:SW:1):Old State = IKE_QM_SPI_STARVE 
 New State = IKE_QM_R_QM2
*Apr 18 05:59:22.211: IPSEC(key_engine): got a queue event with 2 kei messages
*Apr 18 05:59:22.211: IPSEC(initialize_sas): ,
(key eng. msg.) INBOUND local= 10.10.10.1, remote= 10.10.10.2,
local_proxy= 172.18.124.0/255.255.255.0/0/0 (type=4),
remote_proxy= 20.20.20.0/255.255.255.0/0/0 (type=4),
protocol= ESP, transform= esp-seal esp-sha-hmac (Tunnel),
lifedur= 3600s and 4608000kb,
spi= 0xDD3645C8(3711321544), conn_id= 134219728, keysize= 0, flags= 0x2
*Apr 18 05:59:22.211: IPSEC(initialize_sas): ,
(key eng. msg.) OUTBOUND local= 10.10.10.1, remote= 10.10.10.2,
local_proxy= 172.18.124.0/255.255.255.0/0/0 (type=4),
remote_proxy= 20.20.20.0/255.255.255.0/0/0 (type=4),
protocol= ESP, transform= esp-seal esp-sha-hmac (Tunnel),
lifedur= 3600s and 4608000kb,
spi= 0x7259AADD(1918479069), conn_id= 134219729, keysize= 0, flags= 0xA
*Apr 18 05:59:22.211: IPSEC(kei_proxy): head = cisco, 
map->ivrf = , kei->ivrf =
*Apr 18 05:59:22.211: IPSEC(crypto_ipsec_sa_find_ident_head): 
reconnecting with the same proxies and 10.10.10.2
*Apr 18 05:59:22.211: IPSEC(mtree_add_ident): src 172.18.124.0, 
dest 20.20.20.0, dest_port 0

*Apr 18 05:59:22.211: IPSEC(create_sa): sa created,
(sa) sa_dest= 10.10.10.1, sa_prot= 50,
sa_spi= 0xDD3645C8(3711321544),
sa_trans= esp-seal esp-sha-hmac , sa_conn_id= 134219728
*Apr 18 05:59:22.211: IPSEC(create_sa): sa created,
(sa) sa_dest= 10.10.10.2, sa_prot= 50,
sa_spi= 0x7259AADD(1918479069),
sa_trans= esp-seal esp-sha-hmac , sa_conn_id= 134219729
*Apr 18 05:59:22.339: ISAKMP (0:134217729): received packet 
from 10.10.10.2 dport 500 sport 500 Global (R) QM_IDLE
*Apr 18 05:59:22.339: ISAKMP:(0:1:SW:1):deleting node 1056009800 
error FALSE reason "quick mode done (await)"
*Apr 18 05:59:22.339: ISAKMP:(0:1:SW:1):Node 1056009800, Input = 
IKE_MESG_FROM_PEER, IKE_QM_EXCH
*Apr 18 05:59:22.339: ISAKMP:(0:1:SW:1):Old State = IKE_QM_R_QM2 
New State = IKE_QM_PHASE2_COMPLETE

show Commands

  • show crypto isakmp sa—Shows the Internet Security Association Management Protocol (ISAKMP) Security Association (SA) built between peers.

    R1#show crypto isakmp sa
dst src state conn-id slot
10.10.10.1 10.10.10.2 QM_IDLE 1 0

R2#show crypto isakmp sa
dst src state conn-id slot
10.10.10.1 10.10.10.2 QM_IDLE 1 0

  • show crypto ipsec sa—Shows the IPSec SA built between peers.

    R1#show crypto ipsec sa
interface: Ethernet1/0
Crypto map tag: cisco, local addr. 10.10.10.1

protected vrf:
local ident (addr/mask/prot/port): (172.18.124.0/255.255.255.0/0/0)
remote ident (addr/mask/prot/port): (20.20.20.0/255.255.255.0/0/0)
current_peer: 10.10.10.2:500
PERMIT, flags={origin_is_acl,}
#pkts encaps: 776, #pkts encrypt: 776, #pkts digest: 776
#pkts decaps: 776, #pkts decrypt: 776, #pkts verify: 776
#pkts compressed: 0, #pkts decompressed: 0
#pkts not compressed: 0, #pkts compr. failed: 0
#pkts not decompressed: 0, #pkts decompress failed: 0
#send errors 0, #recv errors 0

local crypto endpt.: 10.10.10.1, remote crypto endpt.: 10.10.10.2
path mtu 1500, media mtu 1500
current outbound spi: 7259AADD

inbound esp sas:
spi: 0xDD3645C8(3711321544)
transform: esp-seal esp-sha-hmac ,
in use settings ={Tunnel, }
slot: 0, conn id: 2000, flow_id: 1, crypto map: cisco
crypto engine type: Software, engine_id: 1
sa timing: remaining key lifetime (k/sec): (4565513/3382)
ike_cookies: 67432FCF F809B638 B84C0CD6 B0BCFFC3
IV size: 0 bytes
replay detection support: Y

inbound ah sas:

inbound pcp sas:

outbound esp sas:
spi: 0x7259AADD(1918479069)
transform: esp-seal esp-sha-hmac ,
in use settings ={Tunnel, }
slot: 0, conn id: 2001, flow_id: 2, crypto map: cisco
crypto engine type: Software, engine_id: 1
sa timing: remaining key lifetime (k/sec): (4565518/3382)
ike_cookies: 67432FCF F809B638 B84C0CD6 B0BCFFC3
IV size: 0 bytes
replay detection support: Y

outbound ah sas:

outbound pcp sas:

R1#

 
R2#show crypto ipsec sa

interface: Ethernet0/0
Crypto map tag: cisco, local addr. 10.10.10.2

protected vrf:
local ident (addr/mask/prot/port): (20.20.20.0/255.255.255.0/0/0)
remote ident (addr/mask/prot/port): (172.18.124.0/255.255.255.0/0/0)
current_peer: 10.10.10.1:500
PERMIT, flags={origin_is_acl,}
#pkts encaps: 776, #pkts encrypt: 776, #pkts digest: 38
#pkts decaps: 776, #pkts decrypt: 776, #pkts verify: 38
#pkts compressed: 0, #pkts decompressed: 0
#pkts not compressed: 0, #pkts compr. failed: 0
#pkts not decompressed: 0, #pkts decompress failed: 0
#send errors 1, #recv errors 0

local crypto endpt.: 10.10.10.2, remote crypto endpt.: 10.10.10.1
path mtu 1500, media mtu 1500
current outbound spi: DD3645C8

inbound esp sas:
spi: 0x7259AADD(1918479069)
transform: esp-seal esp-sha-hmac ,
in use settings ={Tunnel, }
slot: 0, conn id: 2000, flow_id: 3, crypto map: cisco
crypto engine type: Software, engine_id: 1
sa timing: remaining key lifetime (k/sec): (4536995/3410)
ike_cookies: B84C0CD6 B0BCFFC3 67432FCF F809B638
IV size: 0 bytes
replay detection support: Y

inbound ah sas:

inbound pcp sas:

outbound esp sas:
spi: 0xDD3645C8(3711321544)
transform: esp-seal esp-sha-hmac ,
in use settings ={Tunnel, }
slot: 0, conn id: 2001, flow_id: 4, crypto map: cisco
crypto engine type: Software, engine_id: 1
sa timing: remaining key lifetime (k/sec): (4537000/3409)
ike_cookies: B84C0CD6 B0BCFFC3 67432FCF F809B638
IV size: 0 bytes
replay detection support: Y

outbound ah sas:

outbound pcp sas:

Limitations with esp-seal Transform Set

There are three limitations on the use of the esp-seal transform set:

  • The esp-seal transform set can be used only if no crypto accelerators are present. This limitation is present because no current crypto accelerators implement the SEAL encryption transform set, and if a crypto accelerator is present, it will handle all IPSec connections that are negotiated with IKE. If a crypto accelerator is present, the Cisco IOS software will allow the transform set to be configured, but it will warn that it will not be used as long as the crypto accelerator is enabled.

  • The esp-seal transform set can be used only in conjunction with an authentication transform set, namely one of these: esp-md5-hmac, esp-sha-hmac, ah-md5-hmac, or ah-sha-hmac. This limitation is present because SEAL encryption is especially weak when it comes to protecting against modifications of the encrypted packet. Therefore, to prevent such a weakness, an authentication transform set is required (Authentication transform sets are designed to foil such attacks.). If you attempt to configure an IPSec transform set using SEAL without an authentication transform set, an error is generated, and the transform set is rejected.

  • The esp-seal transform set cannot be used with a manually keyed crypto map. This limitation is present because such a configuration would reuse the same keystream for each reboot, which would compromise security. Because of the security issue, such a configuration is prohibited. If you attempt to configure a manually keyed crypto map with a SEAL-based transform set, an error is generated, and the transform set is rejected.

Related Information

Revision History

Revision Publish Date Comments
1.0
16-Apr-2004
Initial Release

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