`p2p/security/tls`: does not handle simultaneous closes

[Jorropo]

Version Information

github.com/libp2p/go-libp2p
cloud.google.com/go v0.65.0
cloud.google.com/go/bigquery v1.8.0
cloud.google.com/go/datastore v1.1.0
cloud.google.com/go/pubsub v1.3.1
cloud.google.com/go/storage v1.10.0
dmitri.shuralyov.com/app/changes v0.0.0-20180602232624-0a106ad413e3
dmitri.shuralyov.com/gpu/mtl v0.0.0-20190408044501-666a987793e9
dmitri.shuralyov.com/html/belt v0.0.0-20180602232347-f7d459c86be0
dmitri.shuralyov.com/service/change v0.0.0-20181023043359-a85b471d5412
dmitri.shuralyov.com/state v0.0.0-20180228185332-28bcc343414c
git.apache.org/thrift.git v0.0.0-20180902110319-2566ecd5d999
github.com/AndreasBriese/bbloom v0.0.0-20190825152654-46b345b51c96
github.com/BurntSushi/toml v0.3.1
github.com/BurntSushi/xgb v0.0.0-20160522181843-27f122750802
github.com/OneOfOne/xxhash v1.2.2
github.com/alecthomas/template v0.0.0-20190718012654-fb15b899a751
github.com/alecthomas/units v0.0.0-20190924025748-f65c72e2690d
github.com/anmitsu/go-shlex v0.0.0-20161002113705-648efa622239
github.com/armon/consul-api v0.0.0-20180202201655-eb2c6b5be1b6
github.com/benbjohnson/clock v1.3.5
github.com/beorn7/perks v1.0.1
github.com/bradfitz/go-smtpd v0.0.0-20170404230938-deb6d6237625
github.com/buger/jsonparser v0.0.0-20181115193947-bf1c66bbce23
github.com/census-instrumentation/opencensus-proto v0.2.1
github.com/cespare/xxhash v1.1.0
github.com/cespare/xxhash/v2 v2.2.0
github.com/chromedp/cdproto v0.0.0-20230802225258-3cf4e6d46a89
github.com/chromedp/chromedp v0.9.2
github.com/chromedp/sysutil v1.0.0
github.com/chzyer/logex v1.1.10
github.com/chzyer/readline v1.5.1
github.com/chzyer/test v0.0.0-20180213035817-a1ea475d72b1
github.com/cilium/ebpf v0.9.1
github.com/client9/misspell v0.3.4
github.com/cncf/udpa/go v0.0.0-20191209042840-269d4d468f6f
github.com/containerd/cgroups v1.1.0
github.com/coreos/etcd v3.3.10+incompatible
github.com/coreos/go-etcd v2.0.0+incompatible
github.com/coreos/go-semver v0.2.0
github.com/coreos/go-systemd v0.0.0-20181012123002-c6f51f82210d
github.com/coreos/go-systemd/v22 v22.5.0
github.com/cpuguy83/go-md2man v1.0.10
github.com/cpuguy83/go-md2man/v2 v2.0.0
github.com/davecgh/go-spew v1.1.1
github.com/davidlazar/go-crypto v0.0.0-20200604182044-b73af7476f6c
github.com/decred/dcrd/crypto/blake256 v1.0.1
github.com/decred/dcrd/dcrec/secp256k1/v4 v4.2.0
github.com/dgraph-io/badger v1.6.2
github.com/dgraph-io/ristretto v0.0.2
github.com/dgryski/go-farm v0.0.0-20190423205320-6a90982ecee2
github.com/docker/go-units v0.5.0
github.com/dustin/go-humanize v1.0.0
github.com/elastic/gosigar v0.14.2
github.com/envoyproxy/go-control-plane v0.9.4
github.com/envoyproxy/protoc-gen-validate v0.1.0
github.com/flynn/go-shlex v0.0.0-20150515145356-3f9db97f8568
github.com/flynn/noise v1.0.0
github.com/francoispqt/gojay v1.2.13
github.com/fsnotify/fsnotify v1.5.4
github.com/ghodss/yaml v1.0.0
github.com/gliderlabs/ssh v0.1.1
github.com/go-errors/errors v1.0.1
github.com/go-gl/glfw v0.0.0-20190409004039-e6da0acd62b1
github.com/go-gl/glfw/v3.3/glfw v0.0.0-20200222043503-6f7a984d4dc4
github.com/go-kit/kit v0.9.0
github.com/go-kit/log v0.2.0
github.com/go-logfmt/logfmt v0.5.1
github.com/go-logr/logr v1.2.4
github.com/go-stack/stack v1.8.0
github.com/go-task/slim-sprig v0.0.0-20230315185526-52ccab3ef572
github.com/gobwas/httphead v0.1.0
github.com/gobwas/pool v0.2.1
github.com/gobwas/ws v1.2.1
github.com/godbus/dbus/v5 v5.1.0
github.com/gogo/protobuf v1.3.2
github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b
github.com/golang/groupcache v0.0.0-20200121045136-8c9f03a8e57e
github.com/golang/lint v0.0.0-20180702182130-06c8688daad7
github.com/golang/mock v1.4.4
github.com/golang/protobuf v1.5.3
github.com/golang/snappy v0.0.0-20180518054509-2e65f85255db
github.com/google/btree v1.0.0
github.com/google/go-cmp v0.5.9
github.com/google/go-github v17.0.0+incompatible
github.com/google/go-querystring v1.0.0
github.com/google/gofuzz v1.0.0
github.com/google/gopacket v1.1.19
github.com/google/martian v2.1.0+incompatible
github.com/google/martian/v3 v3.0.0
github.com/google/pprof v0.0.0-20231023181126-ff6d637d2a7b
github.com/google/renameio v0.1.0
github.com/google/uuid v1.3.0
github.com/googleapis/gax-go v2.0.0+incompatible
github.com/googleapis/gax-go/v2 v2.0.5
github.com/gopherjs/gopherjs v0.0.0-20181017120253-0766667cb4d1
github.com/gorilla/websocket v1.5.0
github.com/gregjones/httpcache v0.0.0-20180305231024-9cad4c3443a7
github.com/grpc-ecosystem/grpc-gateway v1.5.0
github.com/hashicorp/golang-lru v0.5.1
github.com/hashicorp/golang-lru/arc/v2 v2.0.5
github.com/hashicorp/golang-lru/v2 v2.0.5
github.com/hashicorp/hcl v1.0.0
github.com/hpcloud/tail v1.0.0
github.com/huin/goupnp v1.3.0
github.com/ianlancetaylor/demangle v0.0.0-20230524184225-eabc099b10ab
github.com/inconshreveable/mousetrap v1.0.0
github.com/ipfs/go-cid v0.4.1
github.com/ipfs/go-datastore v0.6.0
github.com/ipfs/go-detect-race v0.0.1
github.com/ipfs/go-ds-badger v0.3.0
github.com/ipfs/go-ds-leveldb v0.5.0
github.com/ipfs/go-ipfs-delay v0.0.0-20181109222059-70721b86a9a8
github.com/ipfs/go-ipfs-util v0.0.2
github.com/ipfs/go-log/v2 v2.5.1
github.com/jackpal/go-nat-pmp v1.0.2
github.com/jbenet/go-cienv v0.1.0
github.com/jbenet/go-temp-err-catcher v0.1.0
github.com/jbenet/goprocess v0.1.4
github.com/jellevandenhooff/dkim v0.0.0-20150330215556-f50fe3d243e1
github.com/josharian/intern v1.0.0
github.com/jpillora/backoff v1.0.0
github.com/json-iterator/go v1.1.12
github.com/jstemmer/go-junit-report v0.9.1
github.com/julienschmidt/httprouter v1.3.0
github.com/kisielk/errcheck v1.5.0
github.com/kisielk/gotool v1.0.0
github.com/klauspost/compress v1.17.2
github.com/klauspost/cpuid/v2 v2.2.5
github.com/konsorten/go-windows-terminal-sequences v1.0.3
github.com/koron/go-ssdp v0.0.4
github.com/kr/logfmt v0.0.0-20140226030751-b84e30acd515
github.com/kr/pretty v0.2.1
github.com/kr/pty v1.1.3
github.com/kr/text v0.2.0
github.com/libp2p/go-buffer-pool v0.1.0
github.com/libp2p/go-cidranger v1.1.0
github.com/libp2p/go-flow-metrics v0.1.0
github.com/libp2p/go-libp2p-asn-util v0.3.0
github.com/libp2p/go-libp2p-testing v0.12.0
github.com/libp2p/go-msgio v0.3.0
github.com/libp2p/go-nat v0.2.0
github.com/libp2p/go-netroute v0.2.1
github.com/libp2p/go-openssl v0.1.0
github.com/libp2p/go-reuseport v0.4.0
github.com/libp2p/go-yamux/v4 v4.0.1
github.com/libp2p/zeroconf/v2 v2.2.0
github.com/lunixbochs/vtclean v1.0.0
github.com/magiconair/properties v1.8.0
github.com/mailru/easyjson v0.7.7
github.com/marten-seemann/tcp v0.0.0-20210406111302-dfbc87cc63fd
github.com/mattn/go-isatty v0.0.20
github.com/mattn/go-pointer v0.0.1
github.com/matttproud/golang_protobuf_extensions v1.0.1
github.com/microcosm-cc/bluemonday v1.0.1
github.com/miekg/dns v1.1.56
github.com/mikioh/tcp v0.0.0-20190314235350-803a9b46060c
github.com/mikioh/tcpinfo v0.0.0-20190314235526-30a79bb1804b
github.com/mikioh/tcpopt v0.0.0-20190314235656-172688c1accc
github.com/minio/blake2b-simd v0.0.0-20160723061019-3f5f724cb5b1
github.com/minio/sha256-simd v1.0.1
github.com/mitchellh/go-homedir v1.1.0
github.com/mitchellh/mapstructure v1.1.2
github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd
github.com/modern-go/reflect2 v1.0.2
github.com/mr-tron/base58 v1.2.0
github.com/multiformats/go-base32 v0.1.0
github.com/multiformats/go-base36 v0.2.0
github.com/multiformats/go-multiaddr v0.12.0
github.com/multiformats/go-multiaddr-dns v0.3.1
github.com/multiformats/go-multiaddr-fmt v0.1.0
github.com/multiformats/go-multibase v0.2.0
github.com/multiformats/go-multicodec v0.9.0
github.com/multiformats/go-multihash v0.2.3
github.com/multiformats/go-multistream v0.5.0
github.com/multiformats/go-varint v0.0.7
github.com/mwitkow/go-conntrack v0.0.0-20190716064945-2f068394615f
github.com/neelance/astrewrite v0.0.0-20160511093645-99348263ae86
github.com/neelance/sourcemap v0.0.0-20151028013722-8c68805598ab
github.com/nxadm/tail v1.4.8
github.com/onsi/ginkgo v1.16.5
github.com/onsi/ginkgo/v2 v2.13.0
github.com/onsi/gomega v1.27.10
github.com/opencontainers/runtime-spec v1.1.0
github.com/openzipkin/zipkin-go v0.1.1
github.com/pbnjay/memory v0.0.0-20210728143218-7b4eea64cf58
github.com/pelletier/go-toml v1.2.0
github.com/pion/datachannel v1.5.5
github.com/pion/dtls/v2 v2.2.7
github.com/pion/ice/v2 v2.3.6
github.com/pion/interceptor v0.1.17
github.com/pion/logging v0.2.2
github.com/pion/mdns v0.0.7
github.com/pion/randutil v0.1.0
github.com/pion/rtcp v1.2.10
github.com/pion/rtp v1.7.13
github.com/pion/sctp v1.8.7
github.com/pion/sdp/v3 v3.0.6
github.com/pion/srtp/v2 v2.0.15
github.com/pion/stun v0.6.0
github.com/pion/transport v0.14.1
github.com/pion/transport/v2 v2.2.1
github.com/pion/turn/v2 v2.1.0
github.com/pion/webrtc/v3 v3.2.9
github.com/pkg/errors v0.9.1
github.com/pmezard/go-difflib v1.0.0
github.com/prometheus/client_golang v1.14.0
github.com/prometheus/client_model v0.4.0
github.com/prometheus/common v0.37.0
github.com/prometheus/procfs v0.8.0
github.com/quic-go/qpack v0.4.0
github.com/quic-go/qtls-go1-20 v0.3.4
github.com/quic-go/quic-go v0.39.3
github.com/quic-go/webtransport-go v0.6.0
github.com/raulk/go-watchdog v1.3.0
github.com/rogpeppe/go-internal v1.3.0
github.com/russross/blackfriday v1.5.2
github.com/russross/blackfriday/v2 v2.0.1
github.com/sclevine/agouti v3.0.0+incompatible
github.com/sergi/go-diff v1.0.0
github.com/shurcooL/component v0.0.0-20170202220835-f88ec8f54cc4
github.com/shurcooL/events v0.0.0-20181021180414-410e4ca65f48
github.com/shurcooL/github_flavored_markdown v0.0.0-20181002035957-2122de532470
github.com/shurcooL/go v0.0.0-20180423040247-9e1955d9fb6e
github.com/shurcooL/go-goon v0.0.0-20170922171312-37c2f522c041
github.com/shurcooL/gofontwoff v0.0.0-20180329035133-29b52fc0a18d
github.com/shurcooL/gopherjslib v0.0.0-20160914041154-feb6d3990c2c
github.com/shurcooL/highlight_diff v0.0.0-20170515013008-09bb4053de1b
github.com/shurcooL/highlight_go v0.0.0-20181028180052-98c3abbbae20
github.com/shurcooL/home v0.0.0-20181020052607-80b7ffcb30f9
github.com/shurcooL/htmlg v0.0.0-20170918183704-d01228ac9e50
github.com/shurcooL/httperror v0.0.0-20170206035902-86b7830d14cc
github.com/shurcooL/httpfs v0.0.0-20171119174359-809beceb2371
github.com/shurcooL/httpgzip v0.0.0-20180522190206-b1c53ac65af9
github.com/shurcooL/issues v0.0.0-20181008053335-6292fdc1e191
github.com/shurcooL/issuesapp v0.0.0-20180602232740-048589ce2241
github.com/shurcooL/notifications v0.0.0-20181007000457-627ab5aea122
github.com/shurcooL/octicon v0.0.0-20181028054416-fa4f57f9efb2
github.com/shurcooL/reactions v0.0.0-20181006231557-f2e0b4ca5b82
github.com/shurcooL/sanitized_anchor_name v1.0.0
github.com/shurcooL/users v0.0.0-20180125191416-49c67e49c537
github.com/shurcooL/webdavfs v0.0.0-20170829043945-18c3829fa133
github.com/sirupsen/logrus v1.8.1
github.com/sourcegraph/annotate v0.0.0-20160123013949-f4cad6c6324d
github.com/sourcegraph/syntaxhighlight v0.0.0-20170531221838-bd320f5d308e
github.com/spacemonkeygo/spacelog v0.0.0-20180420211403-2296661a0572
github.com/spaolacci/murmur3 v1.1.0
github.com/spf13/afero v1.1.2
github.com/spf13/cast v1.3.0
github.com/spf13/cobra v0.0.5
github.com/spf13/jwalterweatherman v1.0.0
github.com/spf13/pflag v1.0.3
github.com/spf13/viper v1.3.2
github.com/stretchr/objx v0.5.0
github.com/stretchr/testify v1.8.4
github.com/syndtr/goleveldb v1.0.0
github.com/tarm/serial v0.0.0-20180830185346-98f6abe2eb07
github.com/ugorji/go/codec v0.0.0-20181204163529-d75b2dcb6bc8
github.com/urfave/cli v1.22.2
github.com/viant/assertly v0.4.8
github.com/viant/toolbox v0.24.0
github.com/xordataexchange/crypt v0.0.3-0.20170626215501-b2862e3d0a77
github.com/yuin/goldmark v1.4.13
go.opencensus.io v0.22.4
go.uber.org/atomic v1.11.0
go.uber.org/dig v1.17.1
go.uber.org/fx v1.20.1
go.uber.org/goleak v1.2.0
go.uber.org/mock v0.3.0
go.uber.org/multierr v1.11.0
go.uber.org/tools v0.0.0-20190618225709-2cfd321de3ee
go.uber.org/zap v1.26.0
go4.org v0.0.0-20180809161055-417644f6feb5
golang.org/x/build v0.0.0-20190111050920-041ab4dc3f9d
golang.org/x/crypto v0.14.0
golang.org/x/exp v0.0.0-20231006140011-7918f672742d
golang.org/x/image v0.0.0-20190802002840-cff245a6509b
golang.org/x/lint v0.0.0-20200302205851-738671d3881b
golang.org/x/mobile v0.0.0-20190719004257-d2bd2a29d028
golang.org/x/mod v0.13.0
golang.org/x/net v0.17.0
golang.org/x/oauth2 v0.0.0-20220223155221-ee480838109b
golang.org/x/perf v0.0.0-20180704124530-6e6d33e29852
golang.org/x/sync v0.4.0
golang.org/x/sys v0.13.0
golang.org/x/term v0.13.0
golang.org/x/text v0.13.0
golang.org/x/time v0.0.0-20191024005414-555d28b269f0
golang.org/x/tools v0.14.0
golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1
google.golang.org/api v0.30.0
google.golang.org/appengine v1.6.6
google.golang.org/genproto v0.0.0-20200825200019-8632dd797987
google.golang.org/grpc v1.31.0
google.golang.org/protobuf v1.30.0
gopkg.in/alecthomas/kingpin.v2 v2.2.6
gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c
gopkg.in/errgo.v2 v2.1.0
gopkg.in/fsnotify.v1 v1.4.7
gopkg.in/inf.v0 v0.9.1
gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7
gopkg.in/yaml.v2 v2.4.0
gopkg.in/yaml.v3 v3.0.1
grpc.go4.org v0.0.0-20170609214715-11d0a25b4919
honnef.co/go/tools v0.0.1-2020.1.4
lukechampine.com/blake3 v1.2.1
rsc.io/binaryregexp v0.2.0
rsc.io/quote/v3 v3.1.0
rsc.io/sampler v1.3.0
sourcegraph.com/sourcegraph/go-diff v0.5.0
sourcegraph.com/sqs/pbtypes v0.0.0-20180604144634-d3ebe8f20ae4

While writing benchmarks for #2650 I originally wrote:

func benchmarkHandshakes(b *testing.B, factory Factory) {
    privA, pubA, err := crypto.GenerateEd25519Key(crand.Reader)
    assert.NoError(b, err)
    idA, err := peer.IDFromPublicKey(pubA)
    assert.NoError(b, err)
    tptA := factory(b, privA)

    privB, pubB, err := crypto.GenerateEd25519Key(crand.Reader)
    assert.NoError(b, err)
    idB, err := peer.IDFromPublicKey(pubB)
    assert.NoError(b, err)
    tptB := factory(b, privB)

    pipes := make(chan net.Conn, 1)

    var finished sync.Mutex // wait until all data has been transfered
    finished.Lock()
    go func() {
        defer finished.Unlock()
        for p := range pipes {
            conn, err := tptB.SecureInbound(context.Background(), p, idA)
            assert.NoError(b, err)
            assert.NoError(b, conn.Close())
        }
    }()
    b.ResetTimer()

    for i := b.N; i != 0; i-- {
        p1, p2 := net.Pipe()
        pipes <- p2
        conn, err := tptA.SecureOutbound(context.Background(), p1, idB)
        assert.NoError(b, err)
        assert.NoError(b, conn.Close())
    }
    close(pipes)

    finished.Lock()
}

This works with noise but with tls I get:

--- FAIL: BenchmarkTls/handshakes
    bench.go:97: 
            Error Trace:    /home/hugo/k/go-libp2p/p2p/security/internal/benchmark/bench.go:97
                                        /home/hugo/k/go-libp2p/p2p/security/internal/benchmark/bench.go:109
                                        /home/hugo/k/go/src/testing/benchmark.go:197
                                        /home/hugo/k/go/src/testing/benchmark.go:219
                                        /home/hugo/k/go/src/runtime/asm_amd64.s:1695
            Error:          Received unexpected error:
                            tls: failed to send closeNotify alert (but connection was closed anyway): write pipe: i/o timeout
            Test:           BenchmarkTls/handshakes
    bench.go:87: 
            Error Trace:    /home/hugo/k/go-libp2p/p2p/security/internal/benchmark/bench.go:87
                                        /home/hugo/k/go/src/runtime/asm_amd64.s:1695
            Error:          Received unexpected error:
                            tls: failed to send closeNotify alert (but connection was closed anyway): io: read/write on closed pipe
            Test:           BenchmarkTls/handshakes

So I changed it that way:

 func benchmarkHandshakes(b *testing.B, factory Factory) {
    privA, pubA, err := crypto.GenerateEd25519Key(crand.Reader)
    assert.NoError(b, err)
    idA, err := peer.IDFromPublicKey(pubA)
    assert.NoError(b, err)
    tptA := factory(b, privA)

    privB, pubB, err := crypto.GenerateEd25519Key(crand.Reader)
    assert.NoError(b, err)
    idB, err := peer.IDFromPublicKey(pubB)
    assert.NoError(b, err)
    tptB := factory(b, privB)

    pipes := make(chan net.Conn, 1)

    var finished sync.Mutex // wait until all data has been transfered
    finished.Lock()
    go func() {
        defer finished.Unlock()
+       var throwAway [1]byte
        for p := range pipes {
            conn, err := tptB.SecureInbound(context.Background(), p, idA)
            assert.NoError(b, err)
-           assert.NoError(b, conn.Close())
+           _, err = conn.Read(throwAway[:]) // read because currently the tls transport is buggy and don't handle concurrent symetric closes.
+           assert.ErrorIs(b, err, io.EOF)
        }
    }()
    b.ResetTimer()

    for i := b.N; i != 0; i-- {
        p1, p2 := net.Pipe()
        pipes <- p2
        conn, err := tptA.SecureOutbound(context.Background(), p1, idB)
        assert.NoError(b, err)
        assert.NoError(b, conn.Close())
    }
    close(pipes)

    finished.Lock()
 }

In english, I only close on side and the other side pretty wait for it by calling .Read which fixed the issue. This sounds like a bug that could impact production nodes, by making close that should go through fail and wait for timeout.

This maybe be a bug in crypto/tls.

---

p2p/security/noise does not have this issue and return nil nil. (I am not actually sure if noise implements authentified closings, but I hope it does).

[marten-seemann]

This is a quirk of crypto/tls that I run into every time I want to play around with crypto/tls: you need to call Read to drive the handshake on the server side, and you need to call Write (iirc) on the client side to make sure that the handshake actually completes. Not a fan of this API, but there's not much we can do about it.

Or put differently, there's not much that needs to be done about this, since libp2p is running protocols on top of the TLS connection, so the two properties are always satisfied when using this package with libp2p. This still makes it annoying to use for microbenchmarks, but we can probably live with that.

[marten-seemann]

@Jorropo Is there anything you think we should do here, or can we close the issue?

[Jorropo]

It's fine, it handles them after the handshake has been completed. Thx for clarifying this.