diff options
Diffstat (limited to 'pkg/tcpip/transport/tcp/endpoint.go')
| -rw-r--r-- | pkg/tcpip/transport/tcp/endpoint.go | 17 |
1 files changed, 16 insertions, 1 deletions
diff --git a/pkg/tcpip/transport/tcp/endpoint.go b/pkg/tcpip/transport/tcp/endpoint.go index a1cd0d481..f9d5e0085 100644 --- a/pkg/tcpip/transport/tcp/endpoint.go +++ b/pkg/tcpip/transport/tcp/endpoint.go @@ -15,6 +15,7 @@ package tcp import ( + "encoding/binary" "fmt" "math" "strings" @@ -26,6 +27,7 @@ import ( "gvisor.dev/gvisor/pkg/sleep" "gvisor.dev/gvisor/pkg/tcpip" "gvisor.dev/gvisor/pkg/tcpip/buffer" + "gvisor.dev/gvisor/pkg/tcpip/hash/jenkins" "gvisor.dev/gvisor/pkg/tcpip/header" "gvisor.dev/gvisor/pkg/tcpip/iptables" "gvisor.dev/gvisor/pkg/tcpip/seqnum" @@ -1504,7 +1506,20 @@ func (e *endpoint) connect(addr tcpip.FullAddress, handshake bool, run bool) (er // address/port for both local and remote (otherwise this // endpoint would be trying to connect to itself). sameAddr := e.id.LocalAddress == e.id.RemoteAddress - if _, err := e.stack.PickEphemeralPort(func(p uint16) (bool, *tcpip.Error) { + + // Calculate a port offset based on the destination IP/port and + // src IP to ensure that for a given tuple (srcIP, destIP, + // destPort) the offset used as a starting point is the same to + // ensure that we can cycle through the port space effectively. + h := jenkins.Sum32(e.stack.PortSeed()) + h.Write([]byte(e.id.LocalAddress)) + h.Write([]byte(e.id.RemoteAddress)) + portBuf := make([]byte, 2) + binary.LittleEndian.PutUint16(portBuf, e.id.RemotePort) + h.Write(portBuf) + portOffset := h.Sum32() + + if _, err := e.stack.PickEphemeralPortStable(portOffset, func(p uint16) (bool, *tcpip.Error) { if sameAddr && p == e.id.RemotePort { return false, nil } |