From aaa187cd9951b71127c11c375e6a3954a187e1d3 Mon Sep 17 00:00:00 2001 From: Thiago Macieira Date: Sun, 20 Aug 2017 15:50:41 -0700 Subject: QAbstractSocket: Add socketOption for the Path MTU This allow retrieving the value of the known PMTU for the current socket. This works on Linux (IPv6 and IPv4) and FreeBSD (IPv6 only) -- the other OSes don't have the necessary API. Note: do we need add IP_MTU_DISCOVER? Change-Id: I6e9274c1e7444ad48c81fffd14dcaf97a18ce335 Reviewed-by: Edward Welbourne --- src/network/socket/qnativesocketengine_unix.cpp | 30 +++++++++++++++++++++++++ 1 file changed, 30 insertions(+) (limited to 'src/network/socket/qnativesocketengine_unix.cpp') diff --git a/src/network/socket/qnativesocketengine_unix.cpp b/src/network/socket/qnativesocketengine_unix.cpp index cb0a521360..b380b0f7d6 100644 --- a/src/network/socket/qnativesocketengine_unix.cpp +++ b/src/network/socket/qnativesocketengine_unix.cpp @@ -223,6 +223,20 @@ static void convertToLevelAndOption(QNativeSocketEngine::SocketOption opt, #ifdef IP_RECVTTL // IP_RECVTTL is a non-standard extension supported on some OS level = IPPROTO_IP; n = IP_RECVTTL; +#endif + } + break; + + case QNativeSocketEngine::PathMtuInformation: + if (socketProtocol == QAbstractSocket::IPv6Protocol || socketProtocol == QAbstractSocket::AnyIPProtocol) { +#ifdef IPV6_MTU + level = IPPROTO_IPV6; + n = IPV6_MTU; +#endif + } else { +#ifdef IP_MTU + level = IPPROTO_IP; + n = IP_MTU; #endif } break; @@ -331,6 +345,20 @@ int QNativeSocketEnginePrivate::option(QNativeSocketEngine::SocketOption opt) co return -1; } + case QNativeSocketEngine::PathMtuInformation: +#if defined(IPV6_PATHMTU) && !defined(IPV6_MTU) + // Prefer IPV6_MTU (handled by convertToLevelAndOption), if available + // (Linux); fall back to IPV6_PATHMTU otherwise (FreeBSD): + if (socketProtocol == QAbstractSocket::IPv6Protocol) { + ip6_mtuinfo mtuinfo; + QT_SOCKOPTLEN_T len = sizeof(mtuinfo); + if (::getsockopt(socketDescriptor, IPPROTO_IPV6, IPV6_PATHMTU, &mtuinfo, &len) == 0) + return int(mtuinfo.ip6m_mtu); + return -1; + } +#endif + break; + default: break; } @@ -420,6 +448,8 @@ bool QNativeSocketEnginePrivate::setOption(QNativeSocketEngine::SocketOption opt } #endif + if (n == -1) + return false; return ::setsockopt(socketDescriptor, level, n, (char *) &v, sizeof(v)) == 0; } -- cgit v1.2.3