a685e3fc98
Vndr has a simpler configuration and allows pointing to forked packages. Additionally other docker projects are now using vndr making vendoring in distribution more consistent. Updates letsencrypt to use fork. No longer uses sub-vendored packages. Signed-off-by: Derek McGowan <derek@mcgstyle.net> (github: dmcgowan)
104 lines
2.5 KiB
Go
104 lines
2.5 KiB
Go
package dns
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import "strconv"
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const (
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year68 = 1 << 31 // For RFC1982 (Serial Arithmetic) calculations in 32 bits.
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defaultTtl = 3600 // Default internal TTL.
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DefaultMsgSize = 4096 // DefaultMsgSize is the standard default for messages larger than 512 bytes.
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MinMsgSize = 512 // MinMsgSize is the minimal size of a DNS packet.
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MaxMsgSize = 65535 // MaxMsgSize is the largest possible DNS packet.
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)
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// Error represents a DNS error.
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type Error struct{ err string }
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func (e *Error) Error() string {
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if e == nil {
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return "dns: <nil>"
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}
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return "dns: " + e.err
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}
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// An RR represents a resource record.
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type RR interface {
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// Header returns the header of an resource record. The header contains
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// everything up to the rdata.
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Header() *RR_Header
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// String returns the text representation of the resource record.
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String() string
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// copy returns a copy of the RR
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copy() RR
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// len returns the length (in octets) of the uncompressed RR in wire format.
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len() int
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// pack packs an RR into wire format.
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pack([]byte, int, map[string]int, bool) (int, error)
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}
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// RR_Header is the header all DNS resource records share.
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type RR_Header struct {
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Name string `dns:"cdomain-name"`
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Rrtype uint16
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Class uint16
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Ttl uint32
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Rdlength uint16 // Length of data after header.
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}
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// Header returns itself. This is here to make RR_Header implements the RR interface.
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func (h *RR_Header) Header() *RR_Header { return h }
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// Just to implement the RR interface.
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func (h *RR_Header) copy() RR { return nil }
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func (h *RR_Header) copyHeader() *RR_Header {
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r := new(RR_Header)
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r.Name = h.Name
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r.Rrtype = h.Rrtype
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r.Class = h.Class
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r.Ttl = h.Ttl
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r.Rdlength = h.Rdlength
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return r
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}
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func (h *RR_Header) String() string {
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var s string
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if h.Rrtype == TypeOPT {
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s = ";"
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// and maybe other things
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}
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s += sprintName(h.Name) + "\t"
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s += strconv.FormatInt(int64(h.Ttl), 10) + "\t"
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s += Class(h.Class).String() + "\t"
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s += Type(h.Rrtype).String() + "\t"
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return s
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}
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func (h *RR_Header) len() int {
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l := len(h.Name) + 1
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l += 10 // rrtype(2) + class(2) + ttl(4) + rdlength(2)
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return l
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}
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// ToRFC3597 converts a known RR to the unknown RR representation from RFC 3597.
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func (rr *RFC3597) ToRFC3597(r RR) error {
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buf := make([]byte, r.len()*2)
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off, err := PackRR(r, buf, 0, nil, false)
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if err != nil {
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return err
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}
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buf = buf[:off]
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if int(r.Header().Rdlength) > off {
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return ErrBuf
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}
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rfc3597, _, err := unpackRFC3597(*r.Header(), buf, off-int(r.Header().Rdlength))
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if err != nil {
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return err
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}
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*rr = *rfc3597.(*RFC3597)
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return nil
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}
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