thiago marcos p. santos intel...

Hardening WebKit2

Thiago Marcos P. SantosIntel Corporation

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example.com

Images source: Wikimedia.org

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example.com

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example.com

Images source: Wikimedia.org

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Trademarks and logos belong to their respective owners.Images source: Wikimedia.org

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Trademarks and logos belong to their respective owners.

Web

Kit2

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Trademarks and logos belong to their respective owners.

Linux

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Trademarks and logos belong to their respective owners.

Tizen

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Images source: Wikimedia.org

UIProcess WebProcess

IPC

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UIProcess

WebProcess

IPC

Images source: Wikimedia.org

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UIProcess

WebProcess

NetworkProcess

IPC IPC

Images source: Wikimedia.org

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WebProcess

Trademarks and logos belong to their respective owners.Images source: Wikimedia.org

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WebProcess

Trademarks and logos belong to their respective owners.Images source: Wikimedia.org

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WebProcess

Trademarks and logos belong to their respective owners.Images source: Wikimedia.org

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WebProcess

Trademarks and logos belong to their respective owners.

BrokerProcess

IPC

$HOME/.browser/example.com/* (rw)$HOME/.browser/defaults.conf (r)/usr/share/fonts/* (r)/* (not allowed)Images source: Wikimedia.org

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Seccomp Filters

● Linux Kernel 3.5● Ubuntu 12.04● Whitelist syscalls● Blacklist syscalls● Trap syscalls and inspect its parameters● Make it possible to emulate a syscall● ~370 syscalls: libseccomp for the rescue

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// Load seccomp filters // Load website

fd = open(path) write(fd, data) // IO close(fd) unlink(path) free(pointer)

WebProcess

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// Receive serialized // syscalls

// Execute if allowed

// Send back results

BrokerProcess

IPC

Images source: Wikimedia.org

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Additional information

● Performance implications● open() ~28x slower● 15.000 open()'s in ~590ms

● Source code# ls Source/WebKit2/Shared/linux/SeccompFilters/*

● How to build# ./Tools/Scripts/build-webkit --efl -2 --seccomp-filters

● Documentationhttp://tinyurl.com/seccompwk2

Questions?

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UIProcess WebProcess

IPC

Web

Kit

Trademarks and logos belong to their respective owners.Images source: Wikimedia.org

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UIProcess WebProcess

IPC

Chrom

ium

Trademarks and logos belong to their respective owners.

VirtualPlatform

Images source: Wikimedia.org

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UIProcess WebProcess

IPC

Trademarks and logos belong to their respective owners.Images source: Wikimedia.org

Web

Kit

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UIProcess WebProcess

IPC

Trademarks and logos belong to their respective owners.Images source: Wikimedia.org

Chrom

ium