Documentation
¶
Overview ¶
Package netutil pkg/netutil/copy.go c0-com-util
Package netutil pkg/netutil/net.go c0-com-util
The TinyGo-safe (pure) helpers. Network-interface enumeration + the ipinfo.io HTTP probe live in net_native.go (//go:build !tinygo); their TinyGo stubs are in net_tinygo.go.
Package netutil pkg/netutil/net_linux.go c0-com-util
Package netutil pkg/netutil/net_native.go c0-com-util
Network-interface enumeration + the ipinfo.io HTTP probe. Split out of net.go behind //go:build !tinygo because TinyGo's net.Interface has no Addrs() method and net/http doesn't compile on the TinyGo wasm (js) target. A TinyGo dmsg client needs none of these (it has no host NICs to enumerate); the stubs in net_tinygo.go satisfy any transitive linker reference. See docs/design/tinygo-dmsg-client.md.
Package netutil pkg/netutil/policy.go c0-com-util
Package netutil pkg/netutil/porter.go c0-com-util
Package netutil pkg/netutil/retrier.go c0-com-util
Index ¶
- Constants
- Variables
- func CopyReadWriteCloser(conn1, conn2 io.ReadWriteCloser) error
- func DefaultNetworkInterface() (string, error)
- func DefaultNetworkInterfaceIPs() ([]net.IP, error)
- func ExtractPort(addr net.Addr) (uint16, error)
- func HasPublicIP() (bool, error)
- func IsAdvertisableIP(ip net.IP) bool
- func IsPublicIP(IP net.IP) bool
- func IsVirtualInterface(name string) bool
- func LocalAddresses() ([]string, error)
- func LocalAddressesDetail() (kept, excluded []string, err error)
- func LocalNetworkInterfaceIPs() ([]net.IP, error)
- func LocalProtocol() bool
- func MatchPolicyEntry(entry, ifname string, ip net.IP) bool
- func NetworkInterfaceIPs(name string) ([]net.IP, error)
- func PolicyPermitsIP(ip net.IP) bool
- func RouteSourceIPs() (v4, v6 string)
- func SetAdvertisePolicy(p AddrPolicy)
- func ValidatePolicyEntry(e string) error
- type AddrPolicy
- type EphemeralDiagEntry
- type EphemeralDiagResult
- type IfaceAddr
- type Porter
- func (p *Porter) CloseAll(log logrus.FieldLogger)
- func (p *Porter) Count() int
- func (p *Porter) EphemeralDiag() EphemeralDiagResult
- func (p *Porter) PortValue(port uint16) (interface{}, bool)
- func (p *Porter) RangePortValues(fn func(port uint16, v interface{}) (next bool))
- func (p *Porter) RangePortValuesAndChildren(fn func(port uint16, v PorterValue) (next bool))
- func (p *Porter) Reserve(port uint16, v interface{}) (bool, func())
- func (p *Porter) ReserveChild(port, subPort uint16, v interface{}) (bool, func())
- func (p *Porter) ReserveEphemeral(ctx context.Context, v interface{}) (uint16, func(), error)
- func (p *Porter) ResetEphemeral() int
- func (p *Porter) SweepStaleEphemeral(maxAge time.Duration) int
- type PorterValue
- type Retrier
- type RetryFunc
Constants ¶
const ( DefaultInitBackoff = time.Second DefaultMaxBackoff = time.Second * 20 DefaultTries = int64(0) DefaultFactor = float64(1.3) )
Default values for retrier.
const ( // PorterMinEphemeral is the default minimum ephemeral port. PorterMinEphemeral = uint16(49152) )
Variables ¶
var ErrEphemeralPortSpace = errors.New("ephemeral port space exhausted")
ErrEphemeralPortSpace is returned when no ephemeral ports are available.
var (
ErrMaximumRetriesReached = errors.New("maximum retries attempted without success")
)
Package errors
Functions ¶
func CopyReadWriteCloser ¶
func CopyReadWriteCloser(conn1, conn2 io.ReadWriteCloser) error
CopyReadWriteCloser copies reads and writes between two connections. It returns when either direction encounters an error (including idle timeout).
func DefaultNetworkInterface ¶
DefaultNetworkInterface fetches default network interface name: the interface of each IPv4 default route, one a line, as `ip r` lists them.
Where the routing table cannot be read, as by an Android app, it is the interface the kernel routes a packet to the internet through, then the first usable interface. When none qualifies (airplane mode) it returns "" without error, which callers handle as unknown.
func DefaultNetworkInterfaceIPs ¶
DefaultNetworkInterfaceIPs returns IP addresses for the default network interface
func ExtractPort ¶
ExtractPort returns port of the given UDP or TCP address
func HasPublicIP ¶
HasPublicIP returns true if this machine has at least one publically available IP address
func IsAdvertisableIP ¶
IsAdvertisableIP reports whether ip may be offered to peers as a local address: not loopback, not link-local, and not a CLAT address.
func IsPublicIP ¶
IsPublicIP returns true if the provided IP is public. Obtained from: https://stackoverflow.com/questions/41670155/get-public-ip-in-golang
func IsVirtualInterface ¶
IsVirtualInterface reports whether name is an interface whose addresses must not be advertised to peers (see virtualIfacePrefixes).
func LocalAddresses ¶
LocalAddresses returns the addresses the visor may offer peers: global unicast, on an up interface that is not virtual, and permitted by the advertise policy (see SetAdvertisePolicy).
func LocalAddressesDetail ¶
LocalAddressesDetail is LocalAddresses plus what the advertise policy removed, each as "address (interface)".
func LocalNetworkInterfaceIPs ¶
LocalNetworkInterfaceIPs gets IPs of all local interfaces.
func LocalProtocol ¶
func LocalProtocol() bool
LocalProtocol check a condition to use dmsghttp or direct url
func MatchPolicyEntry ¶
MatchPolicyEntry reports whether entry names the interface or holds the address. A nil ip or an empty name matches only the other kind.
func NetworkInterfaceIPs ¶
NetworkInterfaceIPs gets IPs of network interface with name `name`.
func PolicyPermitsIP ¶
PolicyPermitsIP reports whether the advertise policy lets ip be offered, looking up the interface that holds it.
func RouteSourceIPs ¶
func RouteSourceIPs() (v4, v6 string)
RouteSourceIPs returns the local addresses the kernel would send internet traffic from, per family, or "" for a family with no route. Connecting a UDP socket looks the route up and sends nothing.
func SetAdvertisePolicy ¶
func SetAdvertisePolicy(p AddrPolicy)
SetAdvertisePolicy installs the policy LocalAddresses and the WebRTC ICE filter apply. It is process wide, like the interfaces it filters.
func ValidatePolicyEntry ¶
ValidatePolicyEntry checks one allow, deny or metered entry.
Types ¶
type AddrPolicy ¶
type AddrPolicy struct {
Allow []string `json:"allow,omitempty"`
Deny []string `json:"deny,omitempty"`
}
AddrPolicy decides which local interfaces and addresses the visor offers to peers. An entry is an interface name glob ("wlan*", "eth0") or an address range ("10.0.0.0/8", "192.168.1.5"). Deny wins over allow, and an empty allow list allows everything.
func AdvertisePolicy ¶
func AdvertisePolicy() AddrPolicy
AdvertisePolicy returns the policy in force, the zero policy by default.
func (AddrPolicy) AllowsNamed ¶
func (p AddrPolicy) AllowsNamed(ifname string) bool
AllowsNamed reports whether an allow entry names ifname as an interface. Such an entry brings back an interface the virtual filter would drop.
func (AddrPolicy) DeniesInterface ¶
func (p AddrPolicy) DeniesInterface(ifname string) bool
DeniesInterface reports whether a deny glob names ifname, so no address on it can be offered whatever the address is.
func (AddrPolicy) IsZero ¶
func (p AddrPolicy) IsZero() bool
IsZero reports whether the policy allows every address.
func (AddrPolicy) Permits ¶
func (p AddrPolicy) Permits(ifname string, ip net.IP) bool
Permits reports whether the address ip on interface ifname may be offered.
func (AddrPolicy) Validate ¶
func (p AddrPolicy) Validate() error
Validate rejects an entry that is neither a valid glob nor an address range.
type EphemeralDiagEntry ¶
type EphemeralDiagEntry struct {
Port uint16 `json:"port"`
ValueType string `json:"value_type"` // e.g. "*dmsg.Stream", "<nil>"
ValueInfo string `json:"value_info,omitempty"`
Children int `json:"children,omitempty"`
}
EphemeralDiag returns diagnostic information about ephemeral port reservations. For each ephemeral port, it reports whether the stored value is nil, its type, and (for Stringer values) a short string representation. This helps identify what is holding ephemeral ports when the porter approaches exhaustion.
type EphemeralDiagResult ¶
type EphemeralDiagResult struct {
Total int `json:"total"`
Ephemeral int `json:"ephemeral"`
Listeners int `json:"listeners"`
NilValues int `json:"nil_values"`
TotalReserved uint64 `json:"total_reserved"` // monotonic counter
TotalFreed uint64 `json:"total_freed"` // monotonic counter
LeakRate string `json:"leak_rate"` // current - freed as percentage
TypeCount map[string]int `json:"type_count"`
AgeBucket map[string]int `json:"age_bucket"` // "0-30s", "30s-2m", "2m-5m", "5m-30m", "30m+"
CallerCount map[string]int `json:"caller_count,omitempty"` // caller file:line → count (for entries >2min)
Sample []EphemeralDiagEntry `json:"sample,omitempty"` // first 20 entries
}
type IfaceAddr ¶
IfaceAddr is one address and the interface holding it.
func RouteInterfaces ¶
func RouteInterfaces() []IfaceAddr
RouteInterfaces returns the interfaces and addresses the kernel would send internet traffic from, one per family that has a route.
type Porter ¶
Porter reserves ports.
func (*Porter) CloseAll ¶
func (p *Porter) CloseAll(log logrus.FieldLogger)
CloseAll closes all contained variables that implement io.Closer
func (*Porter) EphemeralDiag ¶
func (p *Porter) EphemeralDiag() EphemeralDiagResult
func (*Porter) RangePortValues ¶
RangePortValues ranges all ports that are currently reserved.
func (*Porter) RangePortValuesAndChildren ¶
func (p *Porter) RangePortValuesAndChildren(fn func(port uint16, v PorterValue) (next bool))
RangePortValuesAndChildren ranges port values and it's contained children.
func (*Porter) Reserve ¶
Reserve a given port. It returns a boolean informing whether the port is reserved, and a function to clear the reservation.
func (*Porter) ReserveChild ¶
ReserveChild reserves a child.
func (*Porter) ReserveEphemeral ¶
ReserveEphemeral reserves a new ephemeral port. It returns the reserved ephemeral port, a function to clear the reservation and an error (if any). Returns ErrEphemeralPortSpace if all ephemeral ports (minEph through 65535) are occupied.
func (*Porter) ResetEphemeral ¶
ResetEphemeral removes all ephemeral port reservations (ports >= minEph), freeing the port space. Well-known ports (listeners) are preserved. Use this to recover from ephemeral port exhaustion without restarting.
func (*Porter) SweepStaleEphemeral ¶
SweepStaleEphemeral closes and frees ephemeral port entries older than maxAge. It calls Close() on entries whose Value implements io.Closer, then deletes the porter entry. Returns the number of entries swept.
This is a safety net for the DMSG stream lifecycle: if the normal cleanup paths (Stream.Read auto-release, explicit Close, session reaping) miss an entry, the sweeper catches it before the 16K port space is exhausted.
type PorterValue ¶
type PorterValue struct {
Value interface{}
Children map[uint16]interface{}
}
PorterValue associates a port value alongside it's children.
type Retrier ¶
type Retrier struct {
// contains filtered or unexported fields
}
Retrier holds a configuration for how retries should be performed
func NewDefaultRetrier ¶
func NewDefaultRetrier(log logrus.FieldLogger) *Retrier
NewDefaultRetrier creates a retrier with default values.
func NewRetrier ¶
func NewRetrier(log logrus.FieldLogger, initBO, maxBO time.Duration, tries int64, factor float64) *Retrier
NewRetrier returns a retrier that is ready to call Do() method
func (*Retrier) Do ¶
Do takes a RetryFunc and attempts to execute it. If it fails with an error it will be retried a maximum of given times with an initBO until it returns nil or an error that is whitelisted
func (*Retrier) WithErrWhitelist ¶
WithErrWhitelist sets a list of errors into the retrier, if the RetryFunc provided to Do() fails with one of them it will return inmediatelly with such error. Calling this function is not thread-safe, and is advised to only use it when initializing the Retrier
Source Files