Dotaz: ipsec site-to-site tunel pinga jen z jedne strany

[y.]

Potreboval bych poradit jak tohle resit. Mam rozbehanout ipsec VPN (site-to-site). Na jednom konci je Ubiquiti Edge Max router (hostname ubnt) a na iface ma verejnou adresu. Neprekvapim, pokud konstatuji, ze uvnitr mam nat. Na druhem konci je Turris Omnia (hostname turris) a na outgoing iface ma soukromou adresu poskytovatele. Nicmene od poskytovatele mam prirazenou i verejnou adresu a router naprosto bez problemu reaguje i pres tu verejnou adresu. Jak je to technologicky reseno nevim, ale chova se to proste jako kdyby byly vsechny porty z verejne adresy smerovany na muj externi iface. Za tim iface take jedu NAT, cili je to externi-IP -> interni IP poskytovatele (10.x) -> interni sit moje (192.168.252.0.24). Jelikoz jsou ty routery napric kontinenty a jelikoz potrebuju obcas neco opravit na jedne ci druhe strane, chtel jsem obe site propojit pres IPSec. Ty interni site nekoliduji, to uz jsem si zmenil. Po dvou dnech prerusovaneho snazeni jsem v situaci, z ubnt pingnu vnitrni adresy site za turris, ale obracene to nejde. Jeste je to bohuzel zkomplikovane (aspon pro moje chapani situace) tim, ze zatimco na ubnt je to reseny pres policies (?) a tedy nevidim zadny interface, na turrisu mi strongswan pri startu vytvori ipsec0 interface. Ocividne nejaky traffic pres ten interface projde, ale jen jednim smere... Kdyz jsem totiz na turris a na pozadi zavolam ping 192.168.250.1 (na pozadi) a koukam na interfacy, vidim nasledujici:

root@turris:~# tcpdump -i ipsec0  -n icmp or udp
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on ipsec0, link-type RAW (Raw IP), capture size 262144 bytes
21:18:00.694485 IP 10.77.154.193 > 192.168.250.1: ICMP echo request, id 41260, seq 0, length 64
21:18:01.695720 IP 10.77.154.193 > 192.168.250.1: ICMP echo request, id 41260, seq 1, length 64
^C
2 packets captured
2 packets received by filter
0 packets dropped by kernel
root@turris:~# tcpdump -i eth1  -n icmp or udp
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), capture size 262144 bytes
//provoz, ale nevidim nic co by se vztahovalo k memu pingu
//i.e. nic jako UDP-encap: ESP(spi=0xc7fd7ae3,seq=0x70), length 132
root@turris:~# tcpdump -i ipsec0  -n icmp or udp
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on ipsec0, link-type RAW (Raw IP), capture size 262144 bytes
21:18:52.704185 IP 10.77.154.193 > 192.168.250.1: ICMP echo request, id 41260, seq 52, length 64
21:18:53.705168 IP 10.77.154.193 > 192.168.250.1: ICMP echo request, id 41260, seq 53, length 64
21:18:54.706153 IP 10.77.154.193 > 192.168.250.1: ICMP echo request, id 41260, seq 54, length 64
^C
3 packets captured
3 packets received by filter
0 packets dropped by kernel

Takze zatim to vypada, ze se po vstupu na ipsec0 packety nekam ztrati. Hadam tedy budto neco v iptables a nebo jeste nekde je neco spatne, ale nevim, na co koukat. Mate nekdo nejaky napad

Na turris:

root@turris:~# ipsec statusall
no files found matching '/etc/strongswan.d/*.conf'
Status of IKE charon daemon (strongSwan 5.3.5, Linux 4.4.91-e8cacce0ae0bf48eea19d58c2e860359-1, armv7l):
  uptime: 59 minutes, since Dec 07 20:40:42 2017
  worker threads: 6 of 16 idle, 6/0/4/0 working, job queue: 0/0/0/0, scheduled: 5
  loaded plugins: charon test-vectors ldap pkcs11 aes des blowfish rc2 sha1 sha2 md4 md5 random nonce x509 
  revocation constraints pubkey pkcs1 pkcs7 pkcs8 pkcs12 pgp dnskey sshkey pem openssl gcrypt af-alg fips-prf 
  gmp agent xcbc cmac hmac ctr ccm gcm curl mysql sqlite attr kernel-libipsec kernel-netlink resolve socket-default
  connmark farp stroke smp updown eap-identity eap-md5 eap-mschapv2 eap-radius eap-tls xauth-generic xauth-eap 
  dhcp whitelist led duplicheck addrblock unity
Listening IP addresses:
  10.77.154.193
  192.168.254.2
  192.168.252.1
  fda0:2209:2f01::1
  192.168.253.1
Connections:
peer-XXX.xxxree.net-tunnel-1:  XXX.xxxree.net,0.0.0.0/0,::/0...yyy.ddns.net,0.0.0.0/0,::/0  IKEv1
peer-XXX.xxxree.net-tunnel-1:   local:  [XXX.xxxree.net] uses pre-shared key authentication
peer-XXX.xxxree.net-tunnel-1:   remote: uses pre-shared key authentication
peer-XXX.xxxree.net-tunnel-1:   child:  192.168.252.0/24 === 192.168.250.0/24 TUNNEL
Routed Connections:
peer-XXX.xxxree.net-tunnel-1{1}:  ROUTED, TUNNEL, reqid 1
peer-XXX.xxxree.net-tunnel-1{1}:   192.168.252.0/24 === 192.168.250.0/24
Security Associations (1 up, 0 connecting):
peer-XXX.xxxree.net-tunnel-1[1]: ESTABLISHED 33 minutes ago, 10.77.154.193[XXX.xxxree.net]...y.y.y.y[y.y.y.y]
peer-XXX.xxxree.net-tunnel-1[1]: IKEv1 SPIs: 3650f1ed90c3ebbe_i 74679c88fb4978f3_r*, pre-shared key reauthentication in 7 hours
peer-XXX.xxxree.net-tunnel-1[1]: IKE proposal: AES_CBC_256/HMAC_SHA1_96/PRF_HMAC_SHA1/MODP_2048
peer-XXX.xxxree.net-tunnel-1{2}:  INSTALLED, TUNNEL, reqid 1, ESP in UDP SPIs: e86905ed_i c7fd7ae3_o
peer-XXX.xxxree.net-tunnel-1{2}:  AES_CBC_256/HMAC_SHA1_96, 9408 bytes_i (112 pkts, 293s ago), 9408 bytes_o (112 pkts, 293s ago), rekeying in 11 minutes
peer-XXX.xxxree.net-tunnel-1{2}:   192.168.252.0/24 === 192.168.250.0/24

Odpovědi

[NN]

21:18:52.704185 IP 10.77.154.193 > 192.168.250.1: ICMP echo request, id 41260, seq 52, length 64
21:18:53.705168 IP 10.77.154.193 > 192.168.250.1: ICMP echo request, id 41260, seq 53, length 64

Nemelo by to nahodou do tulenu chodit ciste = nepremaskovane na 10.77.154.193? Nemas tam nahodou maskaradu na vsechno co jde ven?

[y.]

To bylo ono!

root@turris:~# ping 192.168.250.1
PING 192.168.250.1 (192.168.250.1): 56 data bytes
64 bytes from 192.168.250.1: seq=0 ttl=64 time=109.060 ms
64 bytes from 192.168.250.1: seq=1 ttl=64 time=108.753 ms
64 bytes from 192.168.250.1: seq=2 ttl=64 time=109.128 ms
64 bytes from 192.168.250.1: seq=3 ttl=64 time=108.984 ms

Super, diky moc za nakopnuti Este pro uplnost (snad to nekomu pripadne pomuze)

root@turris:~# tcpdump -i ipsec0  -n icmp or udp
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on ipsec0, link-type RAW (Raw IP), capture size 262144 bytes
03:09:03.749067 IP 192.168.252.1 > 192.168.250.1: ICMP echo request, id 35358, seq 24, length 64
03:09:03.855987 IP 192.168.250.1 > 192.168.252.1: ICMP echo reply, id 35358, seq 24, length 64
03:09:04.750038 IP 192.168.252.1 > 192.168.250.1: ICMP echo request, id 35358, seq 25, length 64
03:09:04.858260 IP 192.168.250.1 > 192.168.252.1: ICMP echo reply, id 35358, seq 25, length 64

a tohle je vypis z eth1 (moje egress iface)

03:08:39.743681 IP 10.77.154.193.4500 > ext-ip-UBNT.4500: UDP-encap: ESP(spi=0xca7b4555,seq=0x5), length 132
03:08:39.850349 IP ext-ip-UBNT.4500 > 10.77.154.193.4500: UDP-encap: ESP(spi=0xb97a7b4f,seq=0x5), length 132
03:08:40.744794 IP 10.77.154.193.4500 > ext-ip-UBNT.4500: UDP-encap: ESP(spi=0xca7b4555,seq=0x6), length 132
03:08:40.852074 IP ext-ip-UBNT.4500 > 10.77.154.193.4500: UDP-encap: ESP(spi=0xb97a7b4f,seq=0x6), length 132
03:08:41.745913 IP 10.77.154.193.4500 > ext-ip-UBNT.4500: UDP-encap: ESP(spi=0xca7b4555,seq=0x7), length 132

kde 10.77.154.193 je egress IP stroje turris (jak jsem rikal, nema verejnou adresu, ale asi nejakou verzi 1:1 NAT nebo neceho takove). Jeste jednou diky!

[y.]

Příloha:

• Screen Shot 2017-12-07 at 21.18.18.png (260820 bytů)

Jeste prikladam obrazek nastaveni. Tu guest zonu a vpn_turris zonu jsem nepridal ja -- jedno je openVPN pristup pres Omnia wizarda a to druhy je guest network od jejich jineho wizarda. Zda se mi, ze vse funguje tak jak ma, ale ocenim pripadnou kontrolu -- kdyis jsem si s tim v zoufalosti hral a mozna jsem neco zkonil. Pokud je to ok, tak tu aspon zustane reference na to, jak to ma nastavene vypadat.