998 lines
20 KiB
Go
998 lines
20 KiB
Go
// Copyright 2018 The etcd Authors
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package proxy
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import (
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"fmt"
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"io"
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mrand "math/rand"
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"net"
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"net/http"
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"net/url"
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"strconv"
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"strings"
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"sync"
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"time"
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"go.etcd.io/etcd/pkg/transport"
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humanize "github.com/dustin/go-humanize"
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"go.uber.org/zap"
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)
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var (
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defaultDialTimeout = 3 * time.Second
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defaultBufferSize = 48 * 1024
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defaultRetryInterval = 10 * time.Millisecond
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defaultLogger *zap.Logger
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)
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func init() {
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var err error
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defaultLogger, err = zap.NewProduction()
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if err != nil {
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panic(err)
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}
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}
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// Server defines proxy server layer that simulates common network faults:
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// latency spikes and packet drop or corruption. The proxy overhead is very
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// small overhead (<500μs per request). Please run tests to compute actual
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// overhead.
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type Server interface {
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// From returns proxy source address in "scheme://host:port" format.
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From() string
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// To returns proxy destination address in "scheme://host:port" format.
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To() string
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// Ready returns when proxy is ready to serve.
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Ready() <-chan struct{}
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// Done returns when proxy has been closed.
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Done() <-chan struct{}
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// Error sends errors while serving proxy.
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Error() <-chan error
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// Close closes listener and transport.
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Close() error
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// PauseAccept stops accepting new connections.
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PauseAccept()
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// UnpauseAccept removes pause operation on accepting new connections.
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UnpauseAccept()
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// DelayAccept adds latency ± random variable to accepting
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// new incoming connections.
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DelayAccept(latency, rv time.Duration)
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// UndelayAccept removes sending latencies.
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UndelayAccept()
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// LatencyAccept returns current latency on accepting
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// new incoming connections.
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LatencyAccept() time.Duration
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// DelayTx adds latency ± random variable for "outgoing" traffic
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// in "sending" layer.
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DelayTx(latency, rv time.Duration)
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// UndelayTx removes sending latencies.
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UndelayTx()
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// LatencyTx returns current send latency.
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LatencyTx() time.Duration
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// DelayRx adds latency ± random variable for "incoming" traffic
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// in "receiving" layer.
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DelayRx(latency, rv time.Duration)
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// UndelayRx removes "receiving" latencies.
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UndelayRx()
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// LatencyRx returns current receive latency.
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LatencyRx() time.Duration
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// ModifyTx alters/corrupts/drops "outgoing" packets from the listener
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// with the given edit function.
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ModifyTx(f func(data []byte) []byte)
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// UnmodifyTx removes modify operation on "forwarding".
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UnmodifyTx()
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// ModifyRx alters/corrupts/drops "incoming" packets to client
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// with the given edit function.
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ModifyRx(f func(data []byte) []byte)
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// UnmodifyRx removes modify operation on "receiving".
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UnmodifyRx()
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// BlackholeTx drops all "outgoing" packets before "forwarding".
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// "BlackholeTx" operation is a wrapper around "ModifyTx" with
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// a function that returns empty bytes.
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BlackholeTx()
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// UnblackholeTx removes blackhole operation on "sending".
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UnblackholeTx()
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// BlackholeRx drops all "incoming" packets to client.
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// "BlackholeRx" operation is a wrapper around "ModifyRx" with
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// a function that returns empty bytes.
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BlackholeRx()
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// UnblackholeRx removes blackhole operation on "receiving".
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UnblackholeRx()
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// PauseTx stops "forwarding" packets; "outgoing" traffic blocks.
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PauseTx()
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// UnpauseTx removes "forwarding" pause operation.
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UnpauseTx()
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// PauseRx stops "receiving" packets; "incoming" traffic blocks.
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PauseRx()
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// UnpauseRx removes "receiving" pause operation.
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UnpauseRx()
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// ResetListener closes and restarts listener.
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ResetListener() error
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}
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// ServerConfig defines proxy server configuration.
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type ServerConfig struct {
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Logger *zap.Logger
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From url.URL
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To url.URL
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TLSInfo transport.TLSInfo
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DialTimeout time.Duration
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BufferSize int
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RetryInterval time.Duration
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}
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type server struct {
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lg *zap.Logger
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from url.URL
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fromPort int
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to url.URL
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toPort int
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tlsInfo transport.TLSInfo
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dialTimeout time.Duration
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bufferSize int
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retryInterval time.Duration
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readyc chan struct{}
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donec chan struct{}
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errc chan error
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closeOnce sync.Once
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closeWg sync.WaitGroup
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listenerMu sync.RWMutex
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listener net.Listener
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pauseAcceptMu sync.Mutex
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pauseAcceptc chan struct{}
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latencyAcceptMu sync.RWMutex
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latencyAccept time.Duration
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modifyTxMu sync.RWMutex
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modifyTx func(data []byte) []byte
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modifyRxMu sync.RWMutex
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modifyRx func(data []byte) []byte
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pauseTxMu sync.Mutex
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pauseTxc chan struct{}
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pauseRxMu sync.Mutex
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pauseRxc chan struct{}
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latencyTxMu sync.RWMutex
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latencyTx time.Duration
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latencyRxMu sync.RWMutex
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latencyRx time.Duration
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}
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// NewServer returns a proxy implementation with no iptables/tc dependencies.
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// The proxy layer overhead is <1ms.
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func NewServer(cfg ServerConfig) Server {
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s := &server{
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lg: cfg.Logger,
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from: cfg.From,
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to: cfg.To,
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tlsInfo: cfg.TLSInfo,
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dialTimeout: cfg.DialTimeout,
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bufferSize: cfg.BufferSize,
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retryInterval: cfg.RetryInterval,
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readyc: make(chan struct{}),
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donec: make(chan struct{}),
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errc: make(chan error, 16),
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pauseAcceptc: make(chan struct{}),
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pauseTxc: make(chan struct{}),
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pauseRxc: make(chan struct{}),
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}
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_, fromPort, err := net.SplitHostPort(cfg.From.Host)
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if err == nil {
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s.fromPort, _ = strconv.Atoi(fromPort)
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}
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var toPort string
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_, toPort, err = net.SplitHostPort(cfg.To.Host)
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if err == nil {
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s.toPort, _ = strconv.Atoi(toPort)
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}
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if s.dialTimeout == 0 {
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s.dialTimeout = defaultDialTimeout
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}
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if s.bufferSize == 0 {
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s.bufferSize = defaultBufferSize
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}
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if s.retryInterval == 0 {
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s.retryInterval = defaultRetryInterval
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}
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if s.lg == nil {
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s.lg = defaultLogger
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}
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close(s.pauseAcceptc)
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close(s.pauseTxc)
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close(s.pauseRxc)
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if strings.HasPrefix(s.from.Scheme, "http") {
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s.from.Scheme = "tcp"
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}
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if strings.HasPrefix(s.to.Scheme, "http") {
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s.to.Scheme = "tcp"
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}
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addr := fmt.Sprintf(":%d", s.fromPort)
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if s.fromPort == 0 { // unix
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addr = s.from.Host
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}
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var ln net.Listener
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if !s.tlsInfo.Empty() {
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ln, err = transport.NewListener(addr, s.from.Scheme, &s.tlsInfo)
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} else {
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ln, err = net.Listen(s.from.Scheme, addr)
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}
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if err != nil {
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s.errc <- err
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s.Close()
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return s
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}
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s.listener = ln
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s.closeWg.Add(1)
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go s.listenAndServe()
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s.lg.Info("started proxying", zap.String("from", s.From()), zap.String("to", s.To()))
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return s
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}
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func (s *server) From() string {
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return fmt.Sprintf("%s://%s", s.from.Scheme, s.from.Host)
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}
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func (s *server) To() string {
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return fmt.Sprintf("%s://%s", s.to.Scheme, s.to.Host)
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}
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// TODO: implement packet reordering from multiple TCP connections
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// buffer packets per connection for awhile, reorder before transmit
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// - https://github.com/etcd-io/etcd/issues/5614
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// - https://github.com/etcd-io/etcd/pull/6918#issuecomment-264093034
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func (s *server) listenAndServe() {
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defer s.closeWg.Done()
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s.lg.Info("proxy is listening on", zap.String("from", s.From()))
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close(s.readyc)
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for {
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s.pauseAcceptMu.Lock()
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pausec := s.pauseAcceptc
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s.pauseAcceptMu.Unlock()
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select {
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case <-pausec:
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case <-s.donec:
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return
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}
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s.latencyAcceptMu.RLock()
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lat := s.latencyAccept
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s.latencyAcceptMu.RUnlock()
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if lat > 0 {
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select {
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case <-time.After(lat):
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case <-s.donec:
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return
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}
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}
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s.listenerMu.RLock()
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ln := s.listener
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s.listenerMu.RUnlock()
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in, err := ln.Accept()
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if err != nil {
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select {
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case s.errc <- err:
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select {
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case <-s.donec:
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return
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default:
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}
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case <-s.donec:
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return
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}
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s.lg.Debug("listener accept error", zap.Error(err))
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if strings.HasSuffix(err.Error(), "use of closed network connection") {
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select {
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case <-time.After(s.retryInterval):
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case <-s.donec:
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return
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}
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s.lg.Debug("listener is closed; retry listening on", zap.String("from", s.From()))
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if err = s.ResetListener(); err != nil {
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select {
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case s.errc <- err:
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select {
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case <-s.donec:
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return
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default:
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}
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case <-s.donec:
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return
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}
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s.lg.Warn("failed to reset listener", zap.Error(err))
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}
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}
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continue
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}
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var out net.Conn
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if !s.tlsInfo.Empty() {
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var tp *http.Transport
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tp, err = transport.NewTransport(s.tlsInfo, s.dialTimeout)
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if err != nil {
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select {
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case s.errc <- err:
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select {
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case <-s.donec:
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return
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default:
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}
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case <-s.donec:
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return
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}
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continue
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}
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out, err = tp.Dial(s.to.Scheme, s.to.Host)
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} else {
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out, err = net.Dial(s.to.Scheme, s.to.Host)
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}
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if err != nil {
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select {
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case s.errc <- err:
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select {
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case <-s.donec:
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return
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default:
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}
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case <-s.donec:
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return
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}
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s.lg.Debug("failed to dial", zap.Error(err))
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continue
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}
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go func() {
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// read incoming bytes from listener, dispatch to outgoing connection
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s.transmit(out, in)
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out.Close()
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in.Close()
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}()
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go func() {
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// read response from outgoing connection, write back to listener
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s.receive(in, out)
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in.Close()
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out.Close()
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}()
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}
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}
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func (s *server) transmit(dst io.Writer, src io.Reader) {
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s.ioCopy(dst, src, proxyTx)
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}
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func (s *server) receive(dst io.Writer, src io.Reader) {
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s.ioCopy(dst, src, proxyRx)
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}
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type proxyType uint8
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const (
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proxyTx proxyType = iota
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proxyRx
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)
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func (s *server) ioCopy(dst io.Writer, src io.Reader, ptype proxyType) {
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buf := make([]byte, s.bufferSize)
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for {
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nr1, err := src.Read(buf)
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if err != nil {
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if err == io.EOF {
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return
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}
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// connection already closed
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if strings.HasSuffix(err.Error(), "read: connection reset by peer") {
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return
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}
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if strings.HasSuffix(err.Error(), "use of closed network connection") {
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return
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}
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select {
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case s.errc <- err:
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select {
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case <-s.donec:
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return
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default:
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}
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case <-s.donec:
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return
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}
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s.lg.Debug("failed to read", zap.Error(err))
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return
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}
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if nr1 == 0 {
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return
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}
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data := buf[:nr1]
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// alters/corrupts/drops data
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switch ptype {
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case proxyTx:
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s.modifyTxMu.RLock()
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if s.modifyTx != nil {
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data = s.modifyTx(data)
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}
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s.modifyTxMu.RUnlock()
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case proxyRx:
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s.modifyRxMu.RLock()
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if s.modifyRx != nil {
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data = s.modifyRx(data)
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}
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s.modifyRxMu.RUnlock()
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default:
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panic("unknown proxy type")
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}
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nr2 := len(data)
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switch ptype {
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case proxyTx:
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s.lg.Debug(
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"modified tx",
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zap.String("data-received", humanize.Bytes(uint64(nr1))),
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zap.String("data-modified", humanize.Bytes(uint64(nr2))),
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zap.String("from", s.From()),
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zap.String("to", s.To()),
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)
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case proxyRx:
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s.lg.Debug(
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"modified rx",
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zap.String("data-received", humanize.Bytes(uint64(nr1))),
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zap.String("data-modified", humanize.Bytes(uint64(nr2))),
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zap.String("from", s.To()),
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zap.String("to", s.From()),
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)
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default:
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panic("unknown proxy type")
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}
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// pause before packet dropping, blocking, and forwarding
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var pausec chan struct{}
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switch ptype {
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case proxyTx:
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s.pauseTxMu.Lock()
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pausec = s.pauseTxc
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s.pauseTxMu.Unlock()
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case proxyRx:
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s.pauseRxMu.Lock()
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pausec = s.pauseRxc
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s.pauseRxMu.Unlock()
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default:
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panic("unknown proxy type")
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}
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select {
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case <-pausec:
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case <-s.donec:
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return
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}
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// pause first, and then drop packets
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if nr2 == 0 {
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continue
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}
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// block before forwarding
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var lat time.Duration
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switch ptype {
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case proxyTx:
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s.latencyTxMu.RLock()
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lat = s.latencyTx
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s.latencyTxMu.RUnlock()
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case proxyRx:
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s.latencyRxMu.RLock()
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lat = s.latencyRx
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s.latencyRxMu.RUnlock()
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default:
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panic("unknown proxy type")
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}
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if lat > 0 {
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select {
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case <-time.After(lat):
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case <-s.donec:
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return
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}
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}
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// now forward packets to target
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var nw int
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nw, err = dst.Write(data)
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if err != nil {
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if err == io.EOF {
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return
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}
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select {
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case s.errc <- err:
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select {
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case <-s.donec:
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return
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default:
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}
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case <-s.donec:
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return
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}
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switch ptype {
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case proxyTx:
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s.lg.Debug("write fail on tx", zap.Error(err))
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case proxyRx:
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s.lg.Debug("write fail on rx", zap.Error(err))
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default:
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panic("unknown proxy type")
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}
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return
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}
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if nr2 != nw {
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select {
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case s.errc <- io.ErrShortWrite:
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select {
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case <-s.donec:
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return
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default:
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}
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case <-s.donec:
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return
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}
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switch ptype {
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case proxyTx:
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s.lg.Debug(
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"write fail on tx; read/write bytes are different",
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zap.Int("read-bytes", nr1),
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zap.Int("write-bytes", nw),
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zap.Error(io.ErrShortWrite),
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)
|
|
case proxyRx:
|
|
s.lg.Debug(
|
|
"write fail on rx; read/write bytes are different",
|
|
zap.Int("read-bytes", nr1),
|
|
zap.Int("write-bytes", nw),
|
|
zap.Error(io.ErrShortWrite),
|
|
)
|
|
default:
|
|
panic("unknown proxy type")
|
|
}
|
|
return
|
|
}
|
|
|
|
switch ptype {
|
|
case proxyTx:
|
|
s.lg.Debug(
|
|
"transmitted",
|
|
zap.String("data-size", humanize.Bytes(uint64(nr1))),
|
|
zap.String("from", s.From()),
|
|
zap.String("to", s.To()),
|
|
)
|
|
case proxyRx:
|
|
s.lg.Debug(
|
|
"received",
|
|
zap.String("data-size", humanize.Bytes(uint64(nr1))),
|
|
zap.String("from", s.To()),
|
|
zap.String("to", s.From()),
|
|
)
|
|
default:
|
|
panic("unknown proxy type")
|
|
}
|
|
}
|
|
}
|
|
|
|
func (s *server) Ready() <-chan struct{} { return s.readyc }
|
|
func (s *server) Done() <-chan struct{} { return s.donec }
|
|
func (s *server) Error() <-chan error { return s.errc }
|
|
func (s *server) Close() (err error) {
|
|
s.closeOnce.Do(func() {
|
|
close(s.donec)
|
|
s.listenerMu.Lock()
|
|
if s.listener != nil {
|
|
err = s.listener.Close()
|
|
s.lg.Info(
|
|
"closed proxy listener",
|
|
zap.String("from", s.From()),
|
|
zap.String("to", s.To()),
|
|
)
|
|
}
|
|
s.lg.Sync()
|
|
s.listenerMu.Unlock()
|
|
})
|
|
s.closeWg.Wait()
|
|
return err
|
|
}
|
|
|
|
func (s *server) PauseAccept() {
|
|
s.pauseAcceptMu.Lock()
|
|
s.pauseAcceptc = make(chan struct{})
|
|
s.pauseAcceptMu.Unlock()
|
|
|
|
s.lg.Info(
|
|
"paused accept",
|
|
zap.String("from", s.From()),
|
|
zap.String("to", s.To()),
|
|
)
|
|
}
|
|
|
|
func (s *server) UnpauseAccept() {
|
|
s.pauseAcceptMu.Lock()
|
|
select {
|
|
case <-s.pauseAcceptc: // already unpaused
|
|
case <-s.donec:
|
|
s.pauseAcceptMu.Unlock()
|
|
return
|
|
default:
|
|
close(s.pauseAcceptc)
|
|
}
|
|
s.pauseAcceptMu.Unlock()
|
|
|
|
s.lg.Info(
|
|
"unpaused accept",
|
|
zap.String("from", s.From()),
|
|
zap.String("to", s.To()),
|
|
)
|
|
}
|
|
|
|
func (s *server) DelayAccept(latency, rv time.Duration) {
|
|
if latency <= 0 {
|
|
return
|
|
}
|
|
d := computeLatency(latency, rv)
|
|
s.latencyAcceptMu.Lock()
|
|
s.latencyAccept = d
|
|
s.latencyAcceptMu.Unlock()
|
|
|
|
s.lg.Info(
|
|
"set accept latency",
|
|
zap.Duration("latency", d),
|
|
zap.Duration("given-latency", latency),
|
|
zap.Duration("given-latency-random-variable", rv),
|
|
zap.String("from", s.From()),
|
|
zap.String("to", s.To()),
|
|
)
|
|
}
|
|
|
|
func (s *server) UndelayAccept() {
|
|
s.latencyAcceptMu.Lock()
|
|
d := s.latencyAccept
|
|
s.latencyAccept = 0
|
|
s.latencyAcceptMu.Unlock()
|
|
|
|
s.lg.Info(
|
|
"removed accept latency",
|
|
zap.Duration("latency", d),
|
|
zap.String("from", s.From()),
|
|
zap.String("to", s.To()),
|
|
)
|
|
}
|
|
|
|
func (s *server) LatencyAccept() time.Duration {
|
|
s.latencyAcceptMu.RLock()
|
|
d := s.latencyAccept
|
|
s.latencyAcceptMu.RUnlock()
|
|
return d
|
|
}
|
|
|
|
func (s *server) DelayTx(latency, rv time.Duration) {
|
|
if latency <= 0 {
|
|
return
|
|
}
|
|
d := computeLatency(latency, rv)
|
|
s.latencyTxMu.Lock()
|
|
s.latencyTx = d
|
|
s.latencyTxMu.Unlock()
|
|
|
|
s.lg.Info(
|
|
"set transmit latency",
|
|
zap.Duration("latency", d),
|
|
zap.Duration("given-latency", latency),
|
|
zap.Duration("given-latency-random-variable", rv),
|
|
zap.String("from", s.From()),
|
|
zap.String("to", s.To()),
|
|
)
|
|
}
|
|
|
|
func (s *server) UndelayTx() {
|
|
s.latencyTxMu.Lock()
|
|
d := s.latencyTx
|
|
s.latencyTx = 0
|
|
s.latencyTxMu.Unlock()
|
|
|
|
s.lg.Info(
|
|
"removed transmit latency",
|
|
zap.Duration("latency", d),
|
|
zap.String("from", s.From()),
|
|
zap.String("to", s.To()),
|
|
)
|
|
}
|
|
|
|
func (s *server) LatencyTx() time.Duration {
|
|
s.latencyTxMu.RLock()
|
|
d := s.latencyTx
|
|
s.latencyTxMu.RUnlock()
|
|
return d
|
|
}
|
|
|
|
func (s *server) DelayRx(latency, rv time.Duration) {
|
|
if latency <= 0 {
|
|
return
|
|
}
|
|
d := computeLatency(latency, rv)
|
|
s.latencyRxMu.Lock()
|
|
s.latencyRx = d
|
|
s.latencyRxMu.Unlock()
|
|
|
|
s.lg.Info(
|
|
"set receive latency",
|
|
zap.Duration("latency", d),
|
|
zap.Duration("given-latency", latency),
|
|
zap.Duration("given-latency-random-variable", rv),
|
|
zap.String("from", s.To()),
|
|
zap.String("to", s.From()),
|
|
)
|
|
}
|
|
|
|
func (s *server) UndelayRx() {
|
|
s.latencyRxMu.Lock()
|
|
d := s.latencyRx
|
|
s.latencyRx = 0
|
|
s.latencyRxMu.Unlock()
|
|
|
|
s.lg.Info(
|
|
"removed receive latency",
|
|
zap.Duration("latency", d),
|
|
zap.String("from", s.To()),
|
|
zap.String("to", s.From()),
|
|
)
|
|
}
|
|
|
|
func (s *server) LatencyRx() time.Duration {
|
|
s.latencyRxMu.RLock()
|
|
d := s.latencyRx
|
|
s.latencyRxMu.RUnlock()
|
|
return d
|
|
}
|
|
|
|
func computeLatency(lat, rv time.Duration) time.Duration {
|
|
if rv == 0 {
|
|
return lat
|
|
}
|
|
if rv < 0 {
|
|
rv *= -1
|
|
}
|
|
if rv > lat {
|
|
rv = lat / 10
|
|
}
|
|
now := time.Now()
|
|
mrand.Seed(int64(now.Nanosecond()))
|
|
sign := 1
|
|
if now.Second()%2 == 0 {
|
|
sign = -1
|
|
}
|
|
return lat + time.Duration(int64(sign)*mrand.Int63n(rv.Nanoseconds()))
|
|
}
|
|
|
|
func (s *server) ModifyTx(f func([]byte) []byte) {
|
|
s.modifyTxMu.Lock()
|
|
s.modifyTx = f
|
|
s.modifyTxMu.Unlock()
|
|
|
|
s.lg.Info(
|
|
"modifying tx",
|
|
zap.String("from", s.From()),
|
|
zap.String("to", s.To()),
|
|
)
|
|
}
|
|
|
|
func (s *server) UnmodifyTx() {
|
|
s.modifyTxMu.Lock()
|
|
s.modifyTx = nil
|
|
s.modifyTxMu.Unlock()
|
|
|
|
s.lg.Info(
|
|
"unmodifyed tx",
|
|
zap.String("from", s.From()),
|
|
zap.String("to", s.To()),
|
|
)
|
|
}
|
|
|
|
func (s *server) ModifyRx(f func([]byte) []byte) {
|
|
s.modifyRxMu.Lock()
|
|
s.modifyRx = f
|
|
s.modifyRxMu.Unlock()
|
|
s.lg.Info(
|
|
"modifying rx",
|
|
zap.String("from", s.To()),
|
|
zap.String("to", s.From()),
|
|
)
|
|
}
|
|
|
|
func (s *server) UnmodifyRx() {
|
|
s.modifyRxMu.Lock()
|
|
s.modifyRx = nil
|
|
s.modifyRxMu.Unlock()
|
|
|
|
s.lg.Info(
|
|
"unmodifyed rx",
|
|
zap.String("from", s.To()),
|
|
zap.String("to", s.From()),
|
|
)
|
|
}
|
|
|
|
func (s *server) BlackholeTx() {
|
|
s.ModifyTx(func([]byte) []byte { return nil })
|
|
s.lg.Info(
|
|
"blackholed tx",
|
|
zap.String("from", s.From()),
|
|
zap.String("to", s.To()),
|
|
)
|
|
}
|
|
|
|
func (s *server) UnblackholeTx() {
|
|
s.UnmodifyTx()
|
|
s.lg.Info(
|
|
"unblackholed tx",
|
|
zap.String("from", s.From()),
|
|
zap.String("to", s.To()),
|
|
)
|
|
}
|
|
|
|
func (s *server) BlackholeRx() {
|
|
s.ModifyRx(func([]byte) []byte { return nil })
|
|
s.lg.Info(
|
|
"blackholed rx",
|
|
zap.String("from", s.To()),
|
|
zap.String("to", s.From()),
|
|
)
|
|
}
|
|
|
|
func (s *server) UnblackholeRx() {
|
|
s.UnmodifyRx()
|
|
s.lg.Info(
|
|
"unblackholed rx",
|
|
zap.String("from", s.To()),
|
|
zap.String("to", s.From()),
|
|
)
|
|
}
|
|
|
|
func (s *server) PauseTx() {
|
|
s.pauseTxMu.Lock()
|
|
s.pauseTxc = make(chan struct{})
|
|
s.pauseTxMu.Unlock()
|
|
|
|
s.lg.Info(
|
|
"paused tx",
|
|
zap.String("from", s.From()),
|
|
zap.String("to", s.To()),
|
|
)
|
|
}
|
|
|
|
func (s *server) UnpauseTx() {
|
|
s.pauseTxMu.Lock()
|
|
select {
|
|
case <-s.pauseTxc: // already unpaused
|
|
case <-s.donec:
|
|
s.pauseTxMu.Unlock()
|
|
return
|
|
default:
|
|
close(s.pauseTxc)
|
|
}
|
|
s.pauseTxMu.Unlock()
|
|
|
|
s.lg.Info(
|
|
"unpaused tx",
|
|
zap.String("from", s.From()),
|
|
zap.String("to", s.To()),
|
|
)
|
|
}
|
|
|
|
func (s *server) PauseRx() {
|
|
s.pauseRxMu.Lock()
|
|
s.pauseRxc = make(chan struct{})
|
|
s.pauseRxMu.Unlock()
|
|
|
|
s.lg.Info(
|
|
"paused rx",
|
|
zap.String("from", s.To()),
|
|
zap.String("to", s.From()),
|
|
)
|
|
}
|
|
|
|
func (s *server) UnpauseRx() {
|
|
s.pauseRxMu.Lock()
|
|
select {
|
|
case <-s.pauseRxc: // already unpaused
|
|
case <-s.donec:
|
|
s.pauseRxMu.Unlock()
|
|
return
|
|
default:
|
|
close(s.pauseRxc)
|
|
}
|
|
s.pauseRxMu.Unlock()
|
|
|
|
s.lg.Info(
|
|
"unpaused rx",
|
|
zap.String("from", s.To()),
|
|
zap.String("to", s.From()),
|
|
)
|
|
}
|
|
|
|
func (s *server) ResetListener() error {
|
|
s.listenerMu.Lock()
|
|
defer s.listenerMu.Unlock()
|
|
|
|
if err := s.listener.Close(); err != nil {
|
|
// already closed
|
|
if !strings.HasSuffix(err.Error(), "use of closed network connection") {
|
|
return err
|
|
}
|
|
}
|
|
|
|
var ln net.Listener
|
|
var err error
|
|
if !s.tlsInfo.Empty() {
|
|
ln, err = transport.NewListener(s.from.Host, s.from.Scheme, &s.tlsInfo)
|
|
} else {
|
|
ln, err = net.Listen(s.from.Scheme, s.from.Host)
|
|
}
|
|
if err != nil {
|
|
return err
|
|
}
|
|
s.listener = ln
|
|
|
|
s.lg.Info(
|
|
"reset listener on",
|
|
zap.String("from", s.From()),
|
|
)
|
|
return nil
|
|
}
|