/ecapture

capture SSL/TLS text content without CA cert using eBPF.

Primary LanguageCGNU Affero General Public License v3.0AGPL-3.0

简体中文介绍

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eCapture: capture SSL/TLS text content without CA cert by eBPF.


How eCapture works

  • SSL/TLS text context capture, support openssl\gnutls\nspr(nss) libraries.
  • bash audit, capture bash command for Host Security Audit.
  • mysql query SQL audit, support mysqld 5.6\5.7\8.0, and mariadDB.

eCapture Architecure

eCapture User Manual

eCapture User Manual

Getting started

use ELF binary file

Download ELF zip file release , unzip and use by command ./ecapture --help.

check your server BTF config:

cfc4n@vm-server:~$# uname -r
4.18.0-305.3.1.el8.x86_64
cfc4n@vm-server:~$# cat /boot/config-`uname -r` | grep CONFIG_DEBUG_INFO_BTF
CONFIG_DEBUG_INFO_BTF=y

tls command

capture tls text context. Step 1:

./ecapture tls --hex

Step 2:

curl https://github.com

bash command

capture bash command.

ps -ef | grep foo

What's eBPF

eBPF

uprobe HOOK

openssl hook

eCapture hookSSL_write \ SSL_read function of shared library /lib/x86_64-linux-gnu/libssl.so.1.1. get text context, and send message to user space by eBPM map.

Probes: []*manager.Probe{
    {
        Section:          "uprobe/SSL_write",
        EbpfFuncName:     "probe_entry_SSL_write",
        AttachToFuncName: "SSL_write",
        //UprobeOffset:     0x386B0,
        BinaryPath: "/lib/x86_64-linux-gnu/libssl.so.1.1",
    },
    {
        Section:          "uretprobe/SSL_write",
        EbpfFuncName:     "probe_ret_SSL_write",
        AttachToFuncName: "SSL_write",
        //UprobeOffset:     0x386B0,
        BinaryPath: "/lib/x86_64-linux-gnu/libssl.so.1.1",
    },
    {
        Section:          "uprobe/SSL_read",
        EbpfFuncName:     "probe_entry_SSL_read",
        AttachToFuncName: "SSL_read",
        //UprobeOffset:     0x38380,
        BinaryPath: "/lib/x86_64-linux-gnu/libssl.so.1.1",
    },
    {
        Section:          "uretprobe/SSL_read",
        EbpfFuncName:     "probe_ret_SSL_read",
        AttachToFuncName: "SSL_read",
        //UprobeOffset:     0x38380,
        BinaryPath: "/lib/x86_64-linux-gnu/libssl.so.1.1",
    },
    /**/
},

bash readline.so hook

hook /bin/bash readline symbol name.

How to compile

Linux Kernel: >= 4.18.

Tools

  • golang 1.16
  • gcc 10.3.0
  • clang 9.0.0
  • cmake 3.18.4
  • clang backend: llvm 9.0.0
  • pahole >= v1.13
  • kernel config:CONFIG_DEBUG_INFO_BTF=y (Optional, 2022-04-17)

command

git clone git@github.com:ehids/ecapture.git
cd ecapture
make
bin/ecapture --help

compile without BTF

eCapture support NO BTF with command make nocore to compile on 2022/04/17.

make nocore
bin/ecapture --help

Contributing

See CONTRIBUTING for details on submitting patches and the contribution workflow.