search

EricssonResearch / openwebrtc

A cross-platform WebRTC client framework based on GStreamer
http://www.openwebrtc.org
BSD 2-Clause "Simplified" License
1.8k stars 537 forks source link

Use CCCrypt for hardware accelerated SRTP on iOS #199

Open ikonst opened 9 years ago

ikonst commented 9 years ago

Apparently some iOS devices have hardware accelerated AES and SHA-1: http://stackoverflow.com/questions/4812474/does-iphone-support-hardware-accelerated-aes-encryption

The API is: https://developer.apple.com/library/mac/documentation/Darwin/Reference/ManPages/man3/CCCrypt.3cc.html

This can be interesting for energy efficiency. The implementation should probably be in libsrtp, by implementing custom versions of AES_128_GCM, AES_256_GCM and AES_ICM. (Our build of libsrtp implements all of its own codecs, and does not use OpenSSL or GnuTLS.)

superdump commented 9 years ago

I think OpenSSL has such support too. Can libsrtp be built against that? Also, we had problems using system OpenSSL just because of bugs in hardware accelerated crypto previously.

sdroege commented 9 years ago

Changing libsrtp to use crypto functions from openssl/gnutls should be the best way forward here, yes. It reduces code duplication.

superdump commented 9 years ago

It's unclear whether OpenSSL supports hardware AES on iOS.

...wrong button...

ikonst commented 9 years ago

I don't see any indication online of neither OpenSSL nor GnuTLS support for Apple's CCCrypt. Grepping the code for CCCrypt finds nothing.

BTW, I'm not saying we should do it right away, as it's potentially complicated and security-sensitive. I'm just opening a task.