diff options
Diffstat (limited to 'vendor/github.com/vishvananda/netlink/netns_linux.go')
| -rw-r--r-- | vendor/github.com/vishvananda/netlink/netns_linux.go | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/vendor/github.com/vishvananda/netlink/netns_linux.go b/vendor/github.com/vishvananda/netlink/netns_linux.go new file mode 100644 index 000000000..77cf6f469 --- /dev/null +++ b/vendor/github.com/vishvananda/netlink/netns_linux.go @@ -0,0 +1,141 @@ +package netlink + +// Network namespace ID functions +// +// The kernel has a weird concept called the network namespace ID. +// This is different from the file reference in proc (and any bind-mounted +// namespaces, etc.) +// +// Instead, namespaces can be assigned a numeric ID at any time. Once set, +// the ID is fixed. The ID can either be set manually by the user, or +// automatically, triggered by certain kernel actions. The most common kernel +// action that triggers namespace ID creation is moving one end of a veth pair +// in to that namespace. + +import ( + "fmt" + + "github.com/vishvananda/netlink/nl" + "golang.org/x/sys/unix" +) + +// These can be replaced by the values from sys/unix when it is next released. +const ( + _ = iota + NETNSA_NSID + NETNSA_PID + NETNSA_FD +) + +// GetNetNsIdByPid looks up the network namespace ID for a given pid (really thread id). +// Returns -1 if the namespace does not have an ID set. +func (h *Handle) GetNetNsIdByPid(pid int) (int, error) { + return h.getNetNsId(NETNSA_PID, uint32(pid)) +} + +// GetNetNsIdByPid looks up the network namespace ID for a given pid (really thread id). +// Returns -1 if the namespace does not have an ID set. +func GetNetNsIdByPid(pid int) (int, error) { + return pkgHandle.GetNetNsIdByPid(pid) +} + +// SetNetNSIdByPid sets the ID of the network namespace for a given pid (really thread id). +// The ID can only be set for namespaces without an ID already set. +func (h *Handle) SetNetNsIdByPid(pid, nsid int) error { + return h.setNetNsId(NETNSA_PID, uint32(pid), uint32(nsid)) +} + +// SetNetNSIdByPid sets the ID of the network namespace for a given pid (really thread id). +// The ID can only be set for namespaces without an ID already set. +func SetNetNsIdByPid(pid, nsid int) error { + return pkgHandle.SetNetNsIdByPid(pid, nsid) +} + +// GetNetNsIdByFd looks up the network namespace ID for a given fd. +// fd must be an open file descriptor to a namespace file. +// Returns -1 if the namespace does not have an ID set. +func (h *Handle) GetNetNsIdByFd(fd int) (int, error) { + return h.getNetNsId(NETNSA_FD, uint32(fd)) +} + +// GetNetNsIdByFd looks up the network namespace ID for a given fd. +// fd must be an open file descriptor to a namespace file. +// Returns -1 if the namespace does not have an ID set. +func GetNetNsIdByFd(fd int) (int, error) { + return pkgHandle.GetNetNsIdByFd(fd) +} + +// SetNetNSIdByFd sets the ID of the network namespace for a given fd. +// fd must be an open file descriptor to a namespace file. +// The ID can only be set for namespaces without an ID already set. +func (h *Handle) SetNetNsIdByFd(fd, nsid int) error { + return h.setNetNsId(NETNSA_FD, uint32(fd), uint32(nsid)) +} + +// SetNetNSIdByFd sets the ID of the network namespace for a given fd. +// fd must be an open file descriptor to a namespace file. +// The ID can only be set for namespaces without an ID already set. +func SetNetNsIdByFd(fd, nsid int) error { + return pkgHandle.SetNetNsIdByFd(fd, nsid) +} + +// getNetNsId requests the netnsid for a given type-val pair +// type should be either NETNSA_PID or NETNSA_FD +func (h *Handle) getNetNsId(attrType int, val uint32) (int, error) { + req := h.newNetlinkRequest(unix.RTM_GETNSID, unix.NLM_F_REQUEST) + + rtgen := nl.NewRtGenMsg() + req.AddData(rtgen) + + b := make([]byte, 4, 4) + native.PutUint32(b, val) + attr := nl.NewRtAttr(attrType, b) + req.AddData(attr) + + msgs, err := req.Execute(unix.NETLINK_ROUTE, unix.RTM_NEWNSID) + + if err != nil { + return 0, err + } + + for _, m := range msgs { + msg := nl.DeserializeRtGenMsg(m) + + attrs, err := nl.ParseRouteAttr(m[msg.Len():]) + if err != nil { + return 0, err + } + + for _, attr := range attrs { + switch attr.Attr.Type { + case NETNSA_NSID: + return int(int32(native.Uint32(attr.Value))), nil + } + } + } + + return 0, fmt.Errorf("unexpected empty result") +} + +// setNetNsId sets the netnsid for a given type-val pair +// type should be either NETNSA_PID or NETNSA_FD +// The ID can only be set for namespaces without an ID already set +func (h *Handle) setNetNsId(attrType int, val uint32, newnsid uint32) error { + req := h.newNetlinkRequest(unix.RTM_NEWNSID, unix.NLM_F_REQUEST|unix.NLM_F_ACK) + + rtgen := nl.NewRtGenMsg() + req.AddData(rtgen) + + b := make([]byte, 4, 4) + native.PutUint32(b, val) + attr := nl.NewRtAttr(attrType, b) + req.AddData(attr) + + b1 := make([]byte, 4, 4) + native.PutUint32(b1, newnsid) + attr1 := nl.NewRtAttr(NETNSA_NSID, b1) + req.AddData(attr1) + + _, err := req.Execute(unix.NETLINK_ROUTE, unix.RTM_NEWNSID) + return err +} |