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CFC4N edited this page Jun 5, 2022 · 2 revisions

find the netshoot docker ID

docker ps | grep -w netshoot
b37ffd7a8341   nicolaka/netshoot           "/bin/sleep 3600"        50 minutes ago      Up 50 minutes                k8s_netshoot_netshoot-hostnetwork_default_751666e9-5a23-4da1-952f-379288b47f97_0

docker inspect the ID

docker inspect b37ffd7a8341  | grep '"MergedDir"'
                "MergedDir": "/var/lib/docker/overlay2/02c5fe50b9c6a817c47117ebddd8be82cf4095a6ff278f197519b1cedb7c3d75/merged",

find libssl

find /var/lib/docker/overlay2/02c5fe50b9c6a817c47117ebddd8be82cf4095a6ff278f197519b1cedb7c3d75/merged -name "libssl*"

/var/lib/docker/overlay2/02c5fe50b9c6a817c47117ebddd8be82cf4095a6ff278f197519b1cedb7c3d75/merged/lib/libssl.so.1.1
/var/lib/docker/overlay2/02c5fe50b9c6a817c47117ebddd8be82cf4095a6ff278f197519b1cedb7c3d75/merged/usr/lib/libssl.so.1.1

use ecapture with the correct libssl path

ecapture tls --libssl="/var/lib/docker/overlay2/02c5fe50b9c6a817c47117ebddd8be82cf4095a6ff278f197519b1cedb7c3d75/merged/lib/libssl.so.1.1" --hex
2022/05/30 14:02:27 pid info :2825032
2022/05/30 14:02:27 start to run EBPFProbeOPENSSL module
2022/05/30 14:02:27 start to run EBPFProbeGNUTLS module
2022/05/30 14:02:27 HOOK type:2, binrayPath:/var/lib/docker/overlay2/02c5fe50b9c6a817c47117ebddd8be82cf4095a6ff278f197519b1cedb7c3d75/merged/lib/libssl.so.1.1
2022/05/30 14:02:27 libPthread so Path:/lib64/libpthread.so.0
2022/05/30 14:02:27 target all process. 
2022/05/30 14:02:27 start to run EBPFProbeNSPR module
2022/05/30 14:02:27 stat /usr/lib/libnspr4.so: no such file or directory
2022/05/30 14:02:27 HOOK type:2, binrayPath:/lib64/libgnutls.so.30
2022/05/30 14:02:27 target all process.

execute the curl from netshoot pod

kubectl exec -it netshoot-hostnetwork  -- curl -k -v https://10.1.34.88/
*   Trying 10.1.34.88:443...
* Connected to 10.1.34.88 (10.1.34.88) port 443 (#0)
* ALPN: offers h2
* ALPN: offers http/1.1
* TLSv1.3 (OUT), TLS handshake, Client hello (1):
* TLSv1.3 (IN), TLS handshake, Server hello (2):
* TLSv1.2 (IN), TLS handshake, Certificate (11):
* TLSv1.2 (IN), TLS handshake, Server key exchange (12):
* TLSv1.2 (IN), TLS handshake, Server finished (14):
* TLSv1.2 (OUT), TLS handshake, Client key exchange (16):
* TLSv1.2 (OUT), TLS change cipher, Change cipher spec (1):
* TLSv1.2 (OUT), TLS handshake, Finished (20):
* TLSv1.2 (IN), TLS handshake, Finished (20):
* SSL connection using TLSv1.2 / ECDHE-RSA-AES128-GCM-SHA256
* ALPN: server did not agree on a protocol. Uses default.
* Server certificate:
*  subject: C=US; ST=WA; L=Seattle; O=MyCompany; OU=IT; CN=localhost.localdomain; [email protected]
*  start date: Oct  1 19:29:04 2020 GMT
*  expire date: Sep 29 19:29:04 2030 GMT
*  issuer: C=US; ST=WA; L=Seattle; O=MyCompany; OU=IT; CN=localhost.localdomain; [email protected]
*  SSL certificate verify result: self signed certificate (18), continuing anyway.
> GET / HTTP/1.1
> Host: 10.1.34.88
> User-Agent: curl/7.83.1
> Accept: */*
> 
* Mark bundle as not supporting multiuse
* HTTP 1.0, assume close after body
< HTTP/1.0 200 OK
< Server: BigIP
* HTTP/1.0 connection set to keep alive
< Connection: Keep-Alive
< Content-Length: 10
< 
* Connection #0 to host 10.1.34.88 left intact
 IT WORKS

the ecapture output:

2022/05/30 14:03:34 PID:2825502, Comm:curl, TID:2825502, Version:TLS1_2_VERSION, Send 74 bytes to [ADDR_NOT_FOUND], Payload:
GET / HTTP/1.1
Host: 10.1.34.88
User-Agent: curl/7.83.1
Accept: */*


2022/05/30 14:03:34 PID:2825502, Comm:curl, TID:2825502, Version:TLS1_2_VERSION, Recived 88 bytes from [ADDR_NOT_FOUND], Payload:
HTTP/1.0 200 OK
Server: BigIP
Connection: Keep-Alive
Content-Length: 10

 IT WORKS

ref : https://github.com/ehids/ecapture/issues/65

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