[KaranGauswami]

Fixes #353

Problem

For IPv6 transports, the HEP capture sends :: as the source and destination address. The port, IP family, protocol and timestamp fields are correct.

Root cause

In libsofia-sip-ua/tport/tport_logging.c, the IPv6 branches copy the address from the IPv4 member of the su_sockaddr_t union (su_sin.sin_addr.s_addr, 4 bytes).

For an IPv6 socket address, su_sin.sin_addr is at offset 4. In struct sockaddr_in6, offset 4 is sin6_flowinfo, not the address:

offset 0  sin6_family    (2)
offset 2  sin6_port      (2)   <- same offset as sin_port, so ports are correct
offset 4  sin6_flowinfo  (4)   <- the code reads this as "sin_addr"
offset 8  sin6_addr      (16)  <- the real address, never read

The code thus copies 4 bytes of sin6_flowinfo (usually 0) into a 16-byte field that was set to zero before. The result is always ::.

The same problem is in:

• tport_capt_msg_hepv3(): the source and destination IPv6 chunks (0x0005, 0x0006)
• tport_capt_msg_hepv2(): hep_ip6header.hp6_src and hp6_dst

Change

Copy su_sin6.sin6_addr with its full size (16 bytes) in the IPv6 branches of HEPv2 and HEPv3. The IPv4 branches do not change.

Test

• Built commit 3cc785eeb1 with this change and loaded it into FreeSWITCH 1.11.3 (Debian 13, amd64).
• Enabled HEPv3 capture on an IPv6 SIP profile and sent HEP to sngrep and to Homer (heplify-server).
• Sent SIP over UDP and TLS (OPTIONS, REGISTER, INVITE, BYE).

Before the change:

src_ipv6 = ::               src_port = 5099
dst_ipv6 = ::               dst_port = 5060

After the change (documentation addresses shown):

src_ipv6 = 2001:db8:1::10   src_port = 5099
dst_ipv6 = 2001:db8:2::1    dst_port = 5060

The replies show the reverse direction correctly. Homer stores the correct srcIp and dstIp.

I did not test the HEPv2 change separately. It is the same correction.