hostinfo: keep existing neigh with NUD_PERMANENT

go.mod

@@ -3,26 +3,26 @@ module github.com/yoursunny/ndpresponder
 go 1.19
 
 require (
-	github.com/fsouza/go-dockerclient v1.8.3
+	github.com/fsouza/go-dockerclient v1.9.0
 	github.com/google/gopacket v1.1.19
-	github.com/urfave/cli/v2 v2.16.3
+	github.com/urfave/cli/v2 v2.20.3
 	github.com/vishvananda/netlink v1.2.1-beta.2
 	go.uber.org/zap v1.23.0
-	golang.org/x/net v0.0.0-20220926192436-02166a98028e
-	golang.org/x/sys v0.0.0-20220926163933-8cfa568d3c25
+	golang.org/x/net v0.1.0
+	golang.org/x/sys v0.1.0
 	inet.af/netaddr v0.0.0-20220811202034-502d2d690317
 )
 
 require (
 	github.com/Azure/go-ansiterm v0.0.0-20210617225240-d185dfc1b5a1 // indirect
-	github.com/Microsoft/go-winio v0.5.2 // indirect
+	github.com/Microsoft/go-winio v0.6.0 // indirect
 	github.com/Microsoft/hcsshim v0.9.3 // indirect
 	github.com/containerd/cgroups v1.0.3 // indirect
 	github.com/containerd/containerd v1.6.6 // indirect
 	github.com/cpuguy83/go-md2man/v2 v2.0.2 // indirect
-	github.com/docker/docker v20.10.17+incompatible // indirect
+	github.com/docker/docker v20.10.19+incompatible // indirect
 	github.com/docker/go-connections v0.4.0 // indirect
-	github.com/docker/go-units v0.4.0 // indirect
+	github.com/docker/go-units v0.5.0 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
 	github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da // indirect
 	github.com/moby/sys/mount v0.3.3 // indirect
@@ -42,4 +42,6 @@ require (
 	go.uber.org/multierr v1.6.0 // indirect
 	go4.org/intern v0.0.0-20211027215823-ae77deb06f29 // indirect
 	go4.org/unsafe/assume-no-moving-gc v0.0.0-20220617031537-928513b29760 // indirect
+	golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4 // indirect
+	golang.org/x/tools v0.1.12 // indirect
 )

go.sum

@@ -47,8 +47,8 @@ github.com/Microsoft/go-winio v0.4.16/go.mod h1:XB6nPKklQyQ7GC9LdcBEcBl8PF76WugX
 github.com/Microsoft/go-winio v0.4.17-0.20210211115548-6eac466e5fa3/go.mod h1:JPGBdM1cNvN/6ISo+n8V5iA4v8pBzdOpzfwIujj1a84=
 github.com/Microsoft/go-winio v0.4.17-0.20210324224401-5516f17a5958/go.mod h1:JPGBdM1cNvN/6ISo+n8V5iA4v8pBzdOpzfwIujj1a84=
 github.com/Microsoft/go-winio v0.4.17/go.mod h1:JPGBdM1cNvN/6ISo+n8V5iA4v8pBzdOpzfwIujj1a84=
-github.com/Microsoft/go-winio v0.5.2 h1:a9IhgEQBCUEk6QCdml9CiJGhAws+YwffDHEMp1VMrpA=
-github.com/Microsoft/go-winio v0.5.2/go.mod h1:WpS1mjBmmwHBEWmogvA2mj8546UReBk4v8QkMxJ6pZY=
+github.com/Microsoft/go-winio v0.6.0 h1:slsWYD/zyx7lCXoZVlvQrj0hPTM1HI4+v1sIda2yDvg=
+github.com/Microsoft/go-winio v0.6.0/go.mod h1:cTAf44im0RAYeL23bpB+fzCyDH2MJiz2BO69KH/soAE=
 github.com/Microsoft/hcsshim v0.8.6/go.mod h1:Op3hHsoHPAvb6lceZHDtd9OkTew38wNoXnJs8iY7rUg=
 github.com/Microsoft/hcsshim v0.8.7-0.20190325164909-8abdbb8205e4/go.mod h1:Op3hHsoHPAvb6lceZHDtd9OkTew38wNoXnJs8iY7rUg=
 github.com/Microsoft/hcsshim v0.8.7/go.mod h1:OHd7sQqRFrYd3RmSgbgji+ctCwkbq2wbEYNSzOYtcBQ=
@@ -246,17 +246,18 @@ github.com/docker/distribution v0.0.0-20190905152932-14b96e55d84c/go.mod h1:0+TT
 github.com/docker/distribution v2.7.1-0.20190205005809-0d3efadf0154+incompatible/go.mod h1:J2gT2udsDAN96Uj4KfcMRqY0/ypR+oyYUYmja8H+y+w=
 github.com/docker/distribution v2.7.1+incompatible/go.mod h1:J2gT2udsDAN96Uj4KfcMRqY0/ypR+oyYUYmja8H+y+w=
 github.com/docker/docker v1.4.2-0.20190924003213-a8608b5b67c7/go.mod h1:eEKB0N0r5NX/I1kEveEz05bcu8tLC/8azJZsviup8Sk=
-github.com/docker/docker v20.10.17+incompatible h1:JYCuMrWaVNophQTOrMMoSwudOVEfcegoZZrleKc1xwE=
-github.com/docker/docker v20.10.17+incompatible/go.mod h1:eEKB0N0r5NX/I1kEveEz05bcu8tLC/8azJZsviup8Sk=
+github.com/docker/docker v20.10.19+incompatible h1:lzEmjivyNHFHMNAFLXORMBXyGIhw/UP4DvJwvyKYq64=
+github.com/docker/docker v20.10.19+incompatible/go.mod h1:eEKB0N0r5NX/I1kEveEz05bcu8tLC/8azJZsviup8Sk=
 github.com/docker/docker-credential-helpers v0.6.3/go.mod h1:WRaJzqw3CTB9bk10avuGsjVBZsD05qeibJ1/TYlvc0Y=
 github.com/docker/go-connections v0.4.0 h1:El9xVISelRB7BuFusrZozjnkIM5YnzCViNKohAFqRJQ=
 github.com/docker/go-connections v0.4.0/go.mod h1:Gbd7IOopHjR8Iph03tsViu4nIes5XhDvyHbTtUxmeec=
 github.com/docker/go-events v0.0.0-20170721190031-9461782956ad/go.mod h1:Uw6UezgYA44ePAFQYUehOuCzmy5zmg/+nl2ZfMWGkpA=
 github.com/docker/go-events v0.0.0-20190806004212-e31b211e4f1c/go.mod h1:Uw6UezgYA44ePAFQYUehOuCzmy5zmg/+nl2ZfMWGkpA=
 github.com/docker/go-metrics v0.0.0-20180209012529-399ea8c73916/go.mod h1:/u0gXw0Gay3ceNrsHubL3BtdOL2fHf93USgMTe0W5dI=
 github.com/docker/go-metrics v0.0.1/go.mod h1:cG1hvH2utMXtqgqqYE9plW6lDxS3/5ayHzueweSI3Vw=
-github.com/docker/go-units v0.4.0 h1:3uh0PgVws3nIA0Q+MwDC8yjEPf9zjRfZZWXZYDct3Tw=
 github.com/docker/go-units v0.4.0/go.mod h1:fgPhTUdO+D/Jk86RDLlptpiXQzgHJF7gydDDbaIK4Dk=
+github.com/docker/go-units v0.5.0 h1:69rxXcBk27SvSaaxTtLh/8llcHD8vYHT7WSdRZ/jvr4=
+github.com/docker/go-units v0.5.0/go.mod h1:fgPhTUdO+D/Jk86RDLlptpiXQzgHJF7gydDDbaIK4Dk=
 github.com/docker/libtrust v0.0.0-20150114040149-fa567046d9b1/go.mod h1:cyGadeNEkKy96OOhEzfZl+yxihPEzKnqJwvfuSUqbZE=
 github.com/docker/spdystream v0.0.0-20160310174837-449fdfce4d96/go.mod h1:Qh8CwZgvJUkLughtfhJv5dyTYa91l1fOUCrgjqmcifM=
 github.com/docopt/docopt-go v0.0.0-20180111231733-ee0de3bc6815/go.mod h1:WwZ+bS3ebgob9U8Nd0kOddGdZWjyMGR8Wziv+TBNwSE=
@@ -278,8 +279,8 @@ github.com/form3tech-oss/jwt-go v3.2.2+incompatible/go.mod h1:pbq4aXjuKjdthFRnoD
 github.com/frankban/quicktest v1.11.3/go.mod h1:wRf/ReqHper53s+kmmSZizM8NamnL3IM0I9ntUbOk+k=
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
 github.com/fsnotify/fsnotify v1.4.9/go.mod h1:znqG4EE+3YCdAaPaxE2ZRY/06pZUdp0tY4IgpuI1SZQ=
-github.com/fsouza/go-dockerclient v1.8.3 h1:ckb6sG98D607PNQo012YEhQ8hvuRHx7RISIJM5tjkQM=
-github.com/fsouza/go-dockerclient v1.8.3/go.mod h1:oenNB8JjNKY4o8I/sug4Qah9si/7OxH4MjL+u7oBxP8=
+github.com/fsouza/go-dockerclient v1.9.0 h1:KolErz3rXEhwjTuV0VLXcAyB/qFV9bLNZTIHbfpEsOY=
+github.com/fsouza/go-dockerclient v1.9.0/go.mod h1:OjHFPhuiKyqFDhT5owUV9L7+Ta7GPgnxDWb7UuFKuoQ=
 github.com/fullsailor/pkcs7 v0.0.0-20190404230743-d7302db945fa/go.mod h1:KnogPXtdwXqoenmZCw6S+25EAm2MkxbG0deNDu4cbSA=
 github.com/garyburd/redigo v0.0.0-20150301180006-535138d7bcd7/go.mod h1:NR3MbYisc3/PwhQ00EMzDiPmrwpPxAn5GI05/YaO1SY=
 github.com/ghodss/yaml v0.0.0-20150909031657-73d445a93680/go.mod h1:4dBDuWmgqj2HViK6kFavaiC9ZROes6MMH2rRYeMEF04=
@@ -364,7 +365,7 @@ github.com/google/go-cmp v0.5.3/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/
 github.com/google/go-cmp v0.5.4/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.5.6/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
-github.com/google/go-cmp v0.5.8 h1:e6P7q2lk1O+qJJb4BtCQXlK8vWEO8V1ZeuEdJNOqZyg=
+github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
 github.com/google/go-containerregistry v0.5.1/go.mod h1:Ct15B4yir3PLOP5jsy0GNeYVaIZs/MK/Jz5any1wFW0=
 github.com/google/gofuzz v1.0.0/go.mod h1:dBl0BpW6vV/+mYPU4Po3pmUjxk6FQPldtuIdl/M65Eg=
 github.com/google/gofuzz v1.1.0/go.mod h1:dBl0BpW6vV/+mYPU4Po3pmUjxk6FQPldtuIdl/M65Eg=
@@ -638,8 +639,8 @@ github.com/urfave/cli v0.0.0-20171014202726-7bc6a0acffa5/go.mod h1:70zkFmudgCuE/
 github.com/urfave/cli v1.20.0/go.mod h1:70zkFmudgCuE/ngEzBv17Jvp/497gISqfk5gWijbERA=
 github.com/urfave/cli v1.22.1/go.mod h1:Gos4lmkARVdJ6EkW0WaNv/tZAAMe9V7XWyB60NtXRu0=
 github.com/urfave/cli v1.22.2/go.mod h1:Gos4lmkARVdJ6EkW0WaNv/tZAAMe9V7XWyB60NtXRu0=
-github.com/urfave/cli/v2 v2.16.3 h1:gHoFIwpPjoyIMbJp/VFd+/vuD0dAgFK4B6DpEMFJfQk=
-github.com/urfave/cli/v2 v2.16.3/go.mod h1:1CNUng3PtjQMtRzJO4FMXBQvkGtuYRxxiR9xMa7jMwI=
+github.com/urfave/cli/v2 v2.20.3 h1:lOgGidH/N5loaigd9HjFsOIhXSTrzl7tBpHswZ428w4=
+github.com/urfave/cli/v2 v2.20.3/go.mod h1:1CNUng3PtjQMtRzJO4FMXBQvkGtuYRxxiR9xMa7jMwI=
 github.com/vishvananda/netlink v0.0.0-20181108222139-023a6dafdcdf/go.mod h1:+SR5DhBJrl6ZM7CoCKvpw5BKroDKQ+PJqOg65H/2ktk=
 github.com/vishvananda/netlink v1.1.0/go.mod h1:cTgwzPIzzgDAYoQrMm0EdrjRUBkTqKYppBueQtXaqoE=
 github.com/vishvananda/netlink v1.1.1-0.20201029203352-d40f9887b852/go.mod h1:twkDnbuQxJYemMlGd4JFIcuhgX83tXhKS2B/PRMpOho=
@@ -739,6 +740,8 @@ golang.org/x/mod v0.1.1-0.20191107180719-034126e5016b/go.mod h1:QqPTAvyqsEbceGzB
 golang.org/x/mod v0.2.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.3.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.4.2/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
+golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4 h1:6zppjxzCulZykYSLyVDYbneBfbaBIQPYMevg0bEwv2s=
+golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
 golang.org/x/net v0.0.0-20180724234803-3673e40ba225/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20180826012351-8a410e7b638d/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20180906233101-161cd47e91fd/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
@@ -778,8 +781,8 @@ golang.org/x/net v0.0.0-20201224014010-6772e930b67b/go.mod h1:m0MpNAwzfU5UDzcl9v
 golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
 golang.org/x/net v0.0.0-20210405180319-a5a99cb37ef4/go.mod h1:p54w0d4576C0XHj96bSt6lcn1PtDYWL6XObtHCRCNQM=
 golang.org/x/net v0.0.0-20210825183410-e898025ed96a/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
-golang.org/x/net v0.0.0-20220926192436-02166a98028e h1:I51lVG9ykW5AQeTE50sJ0+gJCAF0J78Hf1+1VUCGxDI=
-golang.org/x/net v0.0.0-20220926192436-02166a98028e/go.mod h1:YDH+HFinaLZZlnHAfSS6ZXJJ9M9t4Dl22yv3iI2vPwk=
+golang.org/x/net v0.1.0 h1:hZ/3BUoy5aId7sCpA/Tc5lt8DkFgdVS2onTpJsZ/fl0=
+golang.org/x/net v0.1.0/go.mod h1:Cx3nUiGt4eDBEyega/BKRp+/AlGL8hYe7U9odMt2Cco=
 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
 golang.org/x/oauth2 v0.0.0-20190226205417-e64efc72b421/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
 golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
@@ -869,10 +872,10 @@ golang.org/x/sys v0.0.0-20211025201205-69cdffdb9359/go.mod h1:oPkhp1MJrh7nUepCBc
 golang.org/x/sys v0.0.0-20211116061358-0a5406a5449c/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20211216021012-1d35b9e2eb4e/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.0.0-20220926163933-8cfa568d3c25 h1:nwzwVf0l2Y/lkov/+IYgMMbFyI+QypZDds9RxlSmsFQ=
-golang.org/x/sys v0.0.0-20220926163933-8cfa568d3c25/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.1.0 h1:kunALQeHf1/185U1i0GOB/fy1IPRDDpuoOOqRReG57U=
+golang.org/x/sys v0.1.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
-golang.org/x/term v0.0.0-20220526004731-065cf7ba2467 h1:CBpWXWQpIRjzmkkA+M7q9Fqnwd2mZr3AFqexg8YTfoM=
+golang.org/x/term v0.1.0 h1:g6Z6vPFA9dYBAF7DWcH6sCcOntplXsDKcliusYijMlw=
 golang.org/x/text v0.0.0-20170915032832-14c0d48ead0c/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.1-0.20180807135948-17ff2d5776d2/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
@@ -932,6 +935,8 @@ golang.org/x/tools v0.0.0-20210106214847-113979e3529a/go.mod h1:emZCQorbCU4vsT4f
 golang.org/x/tools v0.1.0/go.mod h1:xkSsbof2nBLbhDlRMhhhyNLN/zl3eTqcnHD5viDpcZ0=
 golang.org/x/tools v0.1.1/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
 golang.org/x/tools v0.1.5/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
+golang.org/x/tools v0.1.12 h1:VveCTK38A2rkS8ZqFY25HIDFscX5X9OoEhJd3quQmXU=
+golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=

hostinfo.go

@@ -27,7 +27,7 @@ func gatherHostInfo() (hi HostInfo, e error) {
 		logEntry.Error("netlink.NewHandle error", zap.Error(e))
 		return hi, nil
 	}
-	defer nl.Delete()
+	defer nl.Close()
 
 	link, e := nl.LinkByIndex(netif.Index)
 	if e != nil {
@@ -51,7 +51,6 @@ func gatherHostInfo() (hi HostInfo, e error) {
 	logEntry.Info("found gateway", zap.Stringer("gateway", hi.GatewayIP))
 
 	var gatewayNeigh *netlink.Neigh
-GWN:
 	for {
 		neighs, e := nl.NeighList(netif.Index, unix.AF_INET6)
 		if e != nil {
@@ -60,22 +59,31 @@ GWN:
 		}
 		for _, neigh := range neighs {
 			ip, _ := netaddr.FromStdIP(neigh.IP)
-			if ip == hi.GatewayIP && len(neigh.HardwareAddr) == 6 &&
-				(neigh.State == unix.NUD_REACHABLE || neigh.State == unix.NUD_NOARP) {
+			if ip != hi.GatewayIP || len(neigh.HardwareAddr) != 6 {
+				continue
+			}
+			switch neigh.State {
+			case unix.NUD_REACHABLE, unix.NUD_NOARP:
 				gatewayNeigh = &neigh
-				break GWN
+				goto NEIGH_SET
+			case unix.NUD_PERMANENT:
+				goto NEIGH_SKIP
 			}
 		}
+
 		exec.Command("/usr/bin/ping", "-c", "1", hi.GatewayIP.String()).Run()
 		logEntry.Debug("waiting for gateway neigh entry")
 		time.Sleep(time.Second)
 	}
+
+NEIGH_SET:
 	gatewayNeigh.State = unix.NUD_NOARP
 	if e = nl.NeighSet(gatewayNeigh); e != nil {
 		logEntry.Error("netlink.NeighSet error", zap.Error(e))
 	} else {
 		logEntry.Info("netlink.NeighSet OK", zap.Stringer("lladdr", gatewayNeigh.HardwareAddr))
 	}
+NEIGH_SKIP:
 
 	return hi, nil
 }

main.go

@@ -35,7 +35,8 @@ var (
 )
 
 var app = &cli.App{
-	Name: "ndpresponder",
+	Name:        "ndpresponder",
+	Description: "IPv6 Neighbor Discovery Responder",
 	Flags: []cli.Flag{
 		&cli.StringFlag{
 			Name:     "ifname",
@@ -54,6 +55,7 @@ var app = &cli.App{
 			Usage:   "Docker network name",
 		},
 	},
+	HideHelpCommand: true,
 	Before: func(c *cli.Context) (e error) {
 		if netif, e = net.InterfaceByName(c.String("ifname")); e != nil {
 			return cli.Exit(e, 1)