diff options
Diffstat (limited to 'vendor/github.com/rsc/letsencrypt/vendor/github.com/miekg/dns/msg_generate.go')
| -rw-r--r-- | vendor/github.com/rsc/letsencrypt/vendor/github.com/miekg/dns/msg_generate.go | 349 |
1 files changed, 349 insertions, 0 deletions
diff --git a/vendor/github.com/rsc/letsencrypt/vendor/github.com/miekg/dns/msg_generate.go b/vendor/github.com/rsc/letsencrypt/vendor/github.com/miekg/dns/msg_generate.go new file mode 100644 index 000000000..4d9f81d43 --- /dev/null +++ b/vendor/github.com/rsc/letsencrypt/vendor/github.com/miekg/dns/msg_generate.go @@ -0,0 +1,349 @@ +//+build ignore + +// msg_generate.go is meant to run with go generate. It will use +// go/{importer,types} to track down all the RR struct types. Then for each type +// it will generate pack/unpack methods based on the struct tags. The generated source is +// written to zmsg.go, and is meant to be checked into git. +package main + +import ( + "bytes" + "fmt" + "go/format" + "go/importer" + "go/types" + "log" + "os" + "strings" +) + +var packageHdr = ` +// *** DO NOT MODIFY *** +// AUTOGENERATED BY go generate from msg_generate.go + +package dns + +` + +// getTypeStruct will take a type and the package scope, and return the +// (innermost) struct if the type is considered a RR type (currently defined as +// those structs beginning with a RR_Header, could be redefined as implementing +// the RR interface). The bool return value indicates if embedded structs were +// resolved. +func getTypeStruct(t types.Type, scope *types.Scope) (*types.Struct, bool) { + st, ok := t.Underlying().(*types.Struct) + if !ok { + return nil, false + } + if st.Field(0).Type() == scope.Lookup("RR_Header").Type() { + return st, false + } + if st.Field(0).Anonymous() { + st, _ := getTypeStruct(st.Field(0).Type(), scope) + return st, true + } + return nil, false +} + +func main() { + // Import and type-check the package + pkg, err := importer.Default().Import("github.com/miekg/dns") + fatalIfErr(err) + scope := pkg.Scope() + + // Collect actual types (*X) + var namedTypes []string + for _, name := range scope.Names() { + o := scope.Lookup(name) + if o == nil || !o.Exported() { + continue + } + if st, _ := getTypeStruct(o.Type(), scope); st == nil { + continue + } + if name == "PrivateRR" { + continue + } + + // Check if corresponding TypeX exists + if scope.Lookup("Type"+o.Name()) == nil && o.Name() != "RFC3597" { + log.Fatalf("Constant Type%s does not exist.", o.Name()) + } + + namedTypes = append(namedTypes, o.Name()) + } + + b := &bytes.Buffer{} + b.WriteString(packageHdr) + + fmt.Fprint(b, "// pack*() functions\n\n") + for _, name := range namedTypes { + o := scope.Lookup(name) + st, _ := getTypeStruct(o.Type(), scope) + + fmt.Fprintf(b, "func (rr *%s) pack(msg []byte, off int, compression map[string]int, compress bool) (int, error) {\n", name) + fmt.Fprint(b, `off, err := rr.Hdr.pack(msg, off, compression, compress) +if err != nil { + return off, err +} +headerEnd := off +`) + for i := 1; i < st.NumFields(); i++ { + o := func(s string) { + fmt.Fprintf(b, s, st.Field(i).Name()) + fmt.Fprint(b, `if err != nil { +return off, err +} +`) + } + + if _, ok := st.Field(i).Type().(*types.Slice); ok { + switch st.Tag(i) { + case `dns:"-"`: // ignored + case `dns:"txt"`: + o("off, err = packStringTxt(rr.%s, msg, off)\n") + case `dns:"opt"`: + o("off, err = packDataOpt(rr.%s, msg, off)\n") + case `dns:"nsec"`: + o("off, err = packDataNsec(rr.%s, msg, off)\n") + case `dns:"domain-name"`: + o("off, err = packDataDomainNames(rr.%s, msg, off, compression, compress)\n") + default: + log.Fatalln(name, st.Field(i).Name(), st.Tag(i)) + } + continue + } + + switch { + case st.Tag(i) == `dns:"-"`: // ignored + case st.Tag(i) == `dns:"cdomain-name"`: + o("off, err = PackDomainName(rr.%s, msg, off, compression, compress)\n") + case st.Tag(i) == `dns:"domain-name"`: + o("off, err = PackDomainName(rr.%s, msg, off, compression, false)\n") + case st.Tag(i) == `dns:"a"`: + o("off, err = packDataA(rr.%s, msg, off)\n") + case st.Tag(i) == `dns:"aaaa"`: + o("off, err = packDataAAAA(rr.%s, msg, off)\n") + case st.Tag(i) == `dns:"uint48"`: + o("off, err = packUint48(rr.%s, msg, off)\n") + case st.Tag(i) == `dns:"txt"`: + o("off, err = packString(rr.%s, msg, off)\n") + + case strings.HasPrefix(st.Tag(i), `dns:"size-base32`): // size-base32 can be packed just like base32 + fallthrough + case st.Tag(i) == `dns:"base32"`: + o("off, err = packStringBase32(rr.%s, msg, off)\n") + + case strings.HasPrefix(st.Tag(i), `dns:"size-base64`): // size-base64 can be packed just like base64 + fallthrough + case st.Tag(i) == `dns:"base64"`: + o("off, err = packStringBase64(rr.%s, msg, off)\n") + + case strings.HasPrefix(st.Tag(i), `dns:"size-hex:SaltLength`): + // directly write instead of using o() so we get the error check in the correct place + field := st.Field(i).Name() + fmt.Fprintf(b, `// Only pack salt if value is not "-", i.e. empty +if rr.%s != "-" { + off, err = packStringHex(rr.%s, msg, off) + if err != nil { + return off, err + } +} +`, field, field) + continue + case strings.HasPrefix(st.Tag(i), `dns:"size-hex`): // size-hex can be packed just like hex + fallthrough + case st.Tag(i) == `dns:"hex"`: + o("off, err = packStringHex(rr.%s, msg, off)\n") + + case st.Tag(i) == `dns:"octet"`: + o("off, err = packStringOctet(rr.%s, msg, off)\n") + case st.Tag(i) == "": + switch st.Field(i).Type().(*types.Basic).Kind() { + case types.Uint8: + o("off, err = packUint8(rr.%s, msg, off)\n") + case types.Uint16: + o("off, err = packUint16(rr.%s, msg, off)\n") + case types.Uint32: + o("off, err = packUint32(rr.%s, msg, off)\n") + case types.Uint64: + o("off, err = packUint64(rr.%s, msg, off)\n") + case types.String: + o("off, err = packString(rr.%s, msg, off)\n") + default: + log.Fatalln(name, st.Field(i).Name()) + } + default: + log.Fatalln(name, st.Field(i).Name(), st.Tag(i)) + } + } + // We have packed everything, only now we know the rdlength of this RR + fmt.Fprintln(b, "rr.Header().Rdlength = uint16(off-headerEnd)") + fmt.Fprintln(b, "return off, nil }\n") + } + + fmt.Fprint(b, "// unpack*() functions\n\n") + for _, name := range namedTypes { + o := scope.Lookup(name) + st, _ := getTypeStruct(o.Type(), scope) + + fmt.Fprintf(b, "func unpack%s(h RR_Header, msg []byte, off int) (RR, int, error) {\n", name) + fmt.Fprintf(b, "rr := new(%s)\n", name) + fmt.Fprint(b, "rr.Hdr = h\n") + fmt.Fprint(b, `if noRdata(h) { +return rr, off, nil + } +var err error +rdStart := off +_ = rdStart + +`) + for i := 1; i < st.NumFields(); i++ { + o := func(s string) { + fmt.Fprintf(b, s, st.Field(i).Name()) + fmt.Fprint(b, `if err != nil { +return rr, off, err +} +`) + } + + // size-* are special, because they reference a struct member we should use for the length. + if strings.HasPrefix(st.Tag(i), `dns:"size-`) { + structMember := structMember(st.Tag(i)) + structTag := structTag(st.Tag(i)) + switch structTag { + case "hex": + fmt.Fprintf(b, "rr.%s, off, err = unpackStringHex(msg, off, off + int(rr.%s))\n", st.Field(i).Name(), structMember) + case "base32": + fmt.Fprintf(b, "rr.%s, off, err = unpackStringBase32(msg, off, off + int(rr.%s))\n", st.Field(i).Name(), structMember) + case "base64": + fmt.Fprintf(b, "rr.%s, off, err = unpackStringBase64(msg, off, off + int(rr.%s))\n", st.Field(i).Name(), structMember) + default: + log.Fatalln(name, st.Field(i).Name(), st.Tag(i)) + } + fmt.Fprint(b, `if err != nil { +return rr, off, err +} +`) + continue + } + + if _, ok := st.Field(i).Type().(*types.Slice); ok { + switch st.Tag(i) { + case `dns:"-"`: // ignored + case `dns:"txt"`: + o("rr.%s, off, err = unpackStringTxt(msg, off)\n") + case `dns:"opt"`: + o("rr.%s, off, err = unpackDataOpt(msg, off)\n") + case `dns:"nsec"`: + o("rr.%s, off, err = unpackDataNsec(msg, off)\n") + case `dns:"domain-name"`: + o("rr.%s, off, err = unpackDataDomainNames(msg, off, rdStart + int(rr.Hdr.Rdlength))\n") + default: + log.Fatalln(name, st.Field(i).Name(), st.Tag(i)) + } + continue + } + + switch st.Tag(i) { + case `dns:"-"`: // ignored + case `dns:"cdomain-name"`: + fallthrough + case `dns:"domain-name"`: + o("rr.%s, off, err = UnpackDomainName(msg, off)\n") + case `dns:"a"`: + o("rr.%s, off, err = unpackDataA(msg, off)\n") + case `dns:"aaaa"`: + o("rr.%s, off, err = unpackDataAAAA(msg, off)\n") + case `dns:"uint48"`: + o("rr.%s, off, err = unpackUint48(msg, off)\n") + case `dns:"txt"`: + o("rr.%s, off, err = unpackString(msg, off)\n") + case `dns:"base32"`: + o("rr.%s, off, err = unpackStringBase32(msg, off, rdStart + int(rr.Hdr.Rdlength))\n") + case `dns:"base64"`: + o("rr.%s, off, err = unpackStringBase64(msg, off, rdStart + int(rr.Hdr.Rdlength))\n") + case `dns:"hex"`: + o("rr.%s, off, err = unpackStringHex(msg, off, rdStart + int(rr.Hdr.Rdlength))\n") + case `dns:"octet"`: + o("rr.%s, off, err = unpackStringOctet(msg, off)\n") + case "": + switch st.Field(i).Type().(*types.Basic).Kind() { + case types.Uint8: + o("rr.%s, off, err = unpackUint8(msg, off)\n") + case types.Uint16: + o("rr.%s, off, err = unpackUint16(msg, off)\n") + case types.Uint32: + o("rr.%s, off, err = unpackUint32(msg, off)\n") + case types.Uint64: + o("rr.%s, off, err = unpackUint64(msg, off)\n") + case types.String: + o("rr.%s, off, err = unpackString(msg, off)\n") + default: + log.Fatalln(name, st.Field(i).Name()) + } + default: + log.Fatalln(name, st.Field(i).Name(), st.Tag(i)) + } + // If we've hit len(msg) we return without error. + if i < st.NumFields()-1 { + fmt.Fprintf(b, `if off == len(msg) { +return rr, off, nil + } +`) + } + } + fmt.Fprintf(b, "return rr, off, err }\n\n") + } + // Generate typeToUnpack map + fmt.Fprintln(b, "var typeToUnpack = map[uint16]func(RR_Header, []byte, int) (RR, int, error){") + for _, name := range namedTypes { + if name == "RFC3597" { + continue + } + fmt.Fprintf(b, "Type%s: unpack%s,\n", name, name) + } + fmt.Fprintln(b, "}\n") + + // gofmt + res, err := format.Source(b.Bytes()) + if err != nil { + b.WriteTo(os.Stderr) + log.Fatal(err) + } + + // write result + f, err := os.Create("zmsg.go") + fatalIfErr(err) + defer f.Close() + f.Write(res) +} + +// structMember will take a tag like dns:"size-base32:SaltLength" and return the last part of this string. +func structMember(s string) string { + fields := strings.Split(s, ":") + if len(fields) == 0 { + return "" + } + f := fields[len(fields)-1] + // f should have a closing " + if len(f) > 1 { + return f[:len(f)-1] + } + return f +} + +// structTag will take a tag like dns:"size-base32:SaltLength" and return base32. +func structTag(s string) string { + fields := strings.Split(s, ":") + if len(fields) < 2 { + return "" + } + return fields[1][len("\"size-"):] +} + +func fatalIfErr(err error) { + if err != nil { + log.Fatal(err) + } +} |