diff options
Diffstat (limited to 'vendor/github.com/miekg/dns/privaterr.go')
-rw-r--r-- | vendor/github.com/miekg/dns/privaterr.go | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/vendor/github.com/miekg/dns/privaterr.go b/vendor/github.com/miekg/dns/privaterr.go new file mode 100644 index 000000000..d256b652e --- /dev/null +++ b/vendor/github.com/miekg/dns/privaterr.go @@ -0,0 +1,113 @@ +package dns + +import "strings" + +// PrivateRdata is an interface used for implementing "Private Use" RR types, see +// RFC 6895. This allows one to experiment with new RR types, without requesting an +// official type code. Also see dns.PrivateHandle and dns.PrivateHandleRemove. +type PrivateRdata interface { + // String returns the text presentation of the Rdata of the Private RR. + String() string + // Parse parses the Rdata of the private RR. + Parse([]string) error + // Pack is used when packing a private RR into a buffer. + Pack([]byte) (int, error) + // Unpack is used when unpacking a private RR from a buffer. + Unpack([]byte) (int, error) + // Copy copies the Rdata into the PrivateRdata argument. + Copy(PrivateRdata) error + // Len returns the length in octets of the Rdata. + Len() int +} + +// PrivateRR represents an RR that uses a PrivateRdata user-defined type. +// It mocks normal RRs and implements dns.RR interface. +type PrivateRR struct { + Hdr RR_Header + Data PrivateRdata + + generator func() PrivateRdata // for copy +} + +// Header return the RR header of r. +func (r *PrivateRR) Header() *RR_Header { return &r.Hdr } + +func (r *PrivateRR) String() string { return r.Hdr.String() + r.Data.String() } + +// Private len and copy parts to satisfy RR interface. +func (r *PrivateRR) len(off int, compression map[string]struct{}) int { + l := r.Hdr.len(off, compression) + l += r.Data.Len() + return l +} + +func (r *PrivateRR) copy() RR { + // make new RR like this: + rr := &PrivateRR{r.Hdr, r.generator(), r.generator} + + if err := r.Data.Copy(rr.Data); err != nil { + panic("dns: got value that could not be used to copy Private rdata: " + err.Error()) + } + + return rr +} + +func (r *PrivateRR) pack(msg []byte, off int, compression compressionMap, compress bool) (int, error) { + n, err := r.Data.Pack(msg[off:]) + if err != nil { + return len(msg), err + } + off += n + return off, nil +} + +func (r *PrivateRR) unpack(msg []byte, off int) (int, error) { + off1, err := r.Data.Unpack(msg[off:]) + off += off1 + return off, err +} + +func (r *PrivateRR) parse(c *zlexer, origin string) *ParseError { + var l lex + text := make([]string, 0, 2) // could be 0..N elements, median is probably 1 +Fetch: + for { + // TODO(miek): we could also be returning _QUOTE, this might or might not + // be an issue (basically parsing TXT becomes hard) + switch l, _ = c.Next(); l.value { + case zNewline, zEOF: + break Fetch + case zString: + text = append(text, l.token) + } + } + + err := r.Data.Parse(text) + if err != nil { + return &ParseError{"", err.Error(), l} + } + + return nil +} + +func (r *PrivateRR) isDuplicate(r2 RR) bool { return false } + +// PrivateHandle registers a private resource record type. It requires +// string and numeric representation of private RR type and generator function as argument. +func PrivateHandle(rtypestr string, rtype uint16, generator func() PrivateRdata) { + rtypestr = strings.ToUpper(rtypestr) + + TypeToRR[rtype] = func() RR { return &PrivateRR{RR_Header{}, generator(), generator} } + TypeToString[rtype] = rtypestr + StringToType[rtypestr] = rtype +} + +// PrivateHandleRemove removes definitions required to support private RR type. +func PrivateHandleRemove(rtype uint16) { + rtypestr, ok := TypeToString[rtype] + if ok { + delete(TypeToRR, rtype) + delete(TypeToString, rtype) + delete(StringToType, rtypestr) + } +} |