Secure RTCP functions are used to protect RTCP traffic. More...

Functions
srtp_err_status_t	srtp_protect_rtcp (srtp_t ctx, void rtcp_hdr, int pkt_octet_len)
	srtp_protect_rtcp() is the Secure RTCP sender-side packet processing function. More...

srtp_err_status_t	srtp_unprotect_rtcp (srtp_t ctx, void srtcp_hdr, int pkt_octet_len)
	srtp_unprotect_rtcp() is the Secure RTCP receiver-side packet processing function. More...

Detailed Description

Secure RTCP functions are used to protect RTCP traffic.

RTCP is the control protocol for RTP. libSRTP protects RTCP traffic in much the same way as it does RTP traffic. The function srtp_protect_rtcp() applies cryptographic protections to outbound RTCP packets, and srtp_unprotect_rtcp() verifies the protections on inbound RTCP packets.

A note on the naming convention: srtp_protect_rtcp() has an srtp_t as its first argument, and thus has `srtp_' as its prefix. The trailing `_rtcp' indicates the protocol on which it acts.

Function Documentation

◆ srtp_protect_rtcp()

srtp_err_status_t srtp_protect_rtcp	(	srtp_t	ctx,
		void *	rtcp_hdr,
		int *	pkt_octet_len
	)

srtp_protect_rtcp() is the Secure RTCP sender-side packet processing function.

The function call srtp_protect_rtcp(ctx, rtp_hdr, len_ptr) applies SRTCP protection to the RTCP packet rtcp_hdr (which has length *len_ptr) using the SRTP session context ctx. If srtp_err_status_ok is returned, then rtp_hdr points to the resulting SRTCP packet and *len_ptr is the number of octets in that packet; otherwise, no assumptions should be made about the value of either data elements.

Warning: This function assumes that it can write the authentication tag into the location in memory immediately following the RTCP packet, and assumes that the RTCP packet is aligned on a 32-bit boundary.; This function assumes that it can write SRTP_MAX_TRAILER_LEN+4 into the location in memory immediately following the RTCP packet. Callers MUST ensure that this much writable memory is available in the buffer that holds the RTCP packet.

Parameters

ctx	is the SRTP context to use in processing the packet.
rtcp_hdr	is a pointer to the RTCP packet (before the call); after the function returns, it points to the srtp packet.
pkt_octet_len	is a pointer to the length in octets of the complete RTCP packet (header and body) before the function call, and of the complete SRTCP packet after the call, if srtp_err_status_ok was returned. Otherwise, the value of the data to which it points is undefined.

Returns

srtp_err_status_ok if there were no problems.
[other] if there was a failure in the cryptographic mechanisms.

◆ srtp_unprotect_rtcp()

srtp_err_status_t srtp_unprotect_rtcp	(	srtp_t	ctx,
		void *	srtcp_hdr,
		int *	pkt_octet_len
	)

srtp_unprotect_rtcp() is the Secure RTCP receiver-side packet processing function.

The function call srtp_unprotect_rtcp(ctx, srtp_hdr, len_ptr) verifies the Secure RTCP protection of the SRTCP packet pointed to by srtcp_hdr (which has length *len_ptr), using the SRTP session context ctx. If srtp_err_status_ok is returned, then srtcp_hdr points to the resulting RTCP packet and *len_ptr is the number of octets in that packet; otherwise, no assumptions should be made about the value of either data elements.

Warning: This function assumes that the SRTCP packet is aligned on a 32-bit boundary.