pylibsrtp

What is pylibsrtp?

pylibsrtp is a Python wrapper around libsrtp, making it possible to encrypt and decrypt Secure Real-time Transport Protocol (SRTP) packets from Python code.

SRTP is a profile of the Real-time Transport Protocol (RTP) which provides confidentiality, message authentication, and replay protection. It is defined by RFC 3711.

You can install pylibsrtp with pip:

$ pip install pylibsrtp

To learn more about pylibsrtp please read the documentation.

Example

#!/usr/bin/env python

from pylibsrtp import Policy, Session

key = (b'\x00' * 30)
rtp = b'\x80\x08\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00' + (b'\xd4' * 160)

# protect RTP
tx_policy = Policy(key=key, ssrc_type=Policy.SSRC_ANY_OUTBOUND)
tx_session = Session(policy=tx_policy)
srtp = tx_session.protect(rtp)

# unprotect RTP
rx_policy = Policy(key=key, ssrc_type=Policy.SSRC_ANY_INBOUND)
rx_session = Session(policy=rx_policy)
rtp2 = rx_session.unprotect(srtp)

# check roundtrip worked!
assert rtp2 == rtp

Building pylibsrtp

If you wish to build pylibsrtp yourself, you will need libsrtp version 2.0 or better.

Linux

On Debian/Ubuntu run:

$ apt install libsrtp2-dev

On Fedora/CentOS run:

$ dnf install libsrtp-devel

macOS

On macOS run:

$ brew install srtp

You will need to set some environment variables to link against libsrtp:

export CFLAGS=-I$(brew --prefix openssl)/include -I$(brew --prefix srtp)/include
export LDFLAGS=-L$(brew --prefix openssl)/lib -L$(brew --prefix srtp)/lib

License

pylibsrtp is released under the BSD license.