Túnel de Sitio a Sitio entre Routers IOS Usando la Configuración de Ejemplo SEAL

Introducción

SEAL (Software Encryption Algorithm) es un algoritmo alternativo a DES (Data Encryption Standard), 3DES (Triple DES) y AES (Advanced Encryption Standard). El cifrado SEAL utiliza una clave de cifrado de 160 bits y tiene un impacto menor en la CPU en comparación con otros algoritmos basados en software. Este documento ilustra cómo configurar un túnel IPSec de LAN a LAN (de sitio a sitio) mediante SEAL.

Prerequisites

Requirements

No hay requisitos específicos para este documento.

Componentes Utilizados

La información que contiene este documento se basa en las siguientes versiones de software y hardware.

• Cisco 7200 Series Routers que ejecutan Cisco IOS® Software Release 12.3(7)T

La información que contiene este documento se creó a partir de los dispositivos en un ambiente de laboratorio específico. Todos los dispositivos que se utilizan en este documento se pusieron en funcionamiento con una configuración verificada (predeterminada). If your network is live, make sure that you understand the potential impact of any command.

Convenciones

Para obtener más información sobre las convenciones del documento, consulte Convenciones de Consejos Técnicos de Cisco.

Configurar

En esta sección encontrará la información para configurar las funciones descritas en este documento.

Nota: Utilice la herramienta de búsqueda de comandos (solo para clientes registrados) para obtener más información sobre los comandos utilizados en este documento.

Diagrama de la red

En este documento, se utiliza esta configuración de red:

Configuraciones

En este documento, se utilizan estas configuraciones:

• Router 1

• Router 2

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

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

Verificación

En esta sección encontrará información que puede utilizar para confirmar que su configuración esté funcionando correctamente.

La herramienta Output Interpreter (sólo para clientes registrados) permite utilizar algunos comandos “show” y ver un análisis del resultado de estos comandos.

• show crypto map—Verifica la configuración en el router.

  Este resultado se toma del 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

En esta sección encontrará información que puede utilizar para solucionar problemas de configuración.

Comandos para resolución de problemas

La herramienta Output Interpreter (sólo para clientes registrados) permite utilizar algunos comandos “show” y ver un análisis del resultado de estos comandos.

Nota: Antes de ejecutar un comando debug, consulte Información Importante sobre Comandos Debug.

Depuraciones ISAMP e IPSec

• show debugging: muestra información sobre los tipos de depuración que están habilitados para el 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

Comandos show

• show crypto isakmp sa: muestra la Asociación de seguridad (SA) del Protocolo de administración de asociaciones de seguridad de Internet (ISAKMP) creada entre pares.

  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—Muestra los IPSec SA construidos entre pares.

  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:

Limitaciones con conjunto de transformación esp-seal

Existen tres limitaciones en el uso del conjunto de transformación esp-seal:

• El conjunto de transformación esp-seal solo se puede utilizar si no hay aceleradores de criptografía presentes. Esta limitación está presente porque ningún acelerador de cifrado actual implementa el conjunto de transformación de cifrado SEAL y, si hay un acelerador de cifrado presente, controlará todas las conexiones IPSec que se negocian con IKE. Si hay un acelerador de criptografía, el software Cisco IOS permitirá configurar el conjunto de transformación, pero advertirá que no se utilizará mientras el acelerador de criptografía esté habilitado.

• El conjunto de transformación esp-seal sólo se puede utilizar junto con un conjunto de transformación de autenticación, a saber, uno de estos: esp-md5-hmac, esp-sha-hmac, ah-md5-hmac o ah-sha-hmac. Esta limitación está presente porque el cifrado SEAL es especialmente débil cuando se trata de proteger contra las modificaciones del paquete cifrado. Por lo tanto, para evitar esta debilidad, se requiere un conjunto de transformación de autenticación (los conjuntos de transformación de autenticación están diseñados para frustrar estos ataques). Si intenta configurar un conjunto de transformación IPSec mediante SEAL sin un conjunto de transformación de autenticación, se genera un error y se rechaza el conjunto de transformación.

• El conjunto de transformación esp-seal no se puede utilizar con un mapa criptográfico con clave manual. Esta limitación está presente porque dicha configuración reutilizaría el mismo flujo de claves para cada reinicio, lo que pondría en peligro la seguridad. Debido al problema de seguridad, dicha configuración está prohibida. Si intenta configurar un mapa criptográfico con clave manual con un conjunto de transformación basado en SEAL, se genera un error y se rechaza el conjunto de transformación.

Información Relacionada

• Página de soporte de IPSec
• Soporte Técnico y Documentación - Cisco Systems