75 lines
1.5 KiB
Go
75 lines
1.5 KiB
Go
package signature
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import (
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"bytes"
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"crypto/ed25519"
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"encoding/base64"
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"io"
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)
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const Len = 86
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type S struct{ Signature []byte }
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func New(sig []byte) (p *S, err error) {
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if len(sig) != ed25519.SignatureSize {
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err = errorf.E("invalid signature size: %d; require %d",
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len(sig), ed25519.SignatureSize)
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return
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}
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p = &S{sig}
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return
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}
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func (p *S) Marshal(dst []byte) (result []byte, err error) {
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result = dst
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if p == nil || p.Signature == nil || len(p.Signature) == 0 {
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err = errorf.E("nil/zero length signature")
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return
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}
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if len(p.Signature) != ed25519.SignatureSize {
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err = errorf.E("invalid signature length %d; require %d '%0x'",
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len(p.Signature), ed25519.SignatureSize, p.Signature)
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return
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}
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buf := bytes.NewBuffer(result)
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w := base64.NewEncoder(base64.RawURLEncoding, buf)
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if _, err = w.Write(p.Signature); chk.E(err) {
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return
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}
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if err = w.Close(); chk.E(err) {
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return
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}
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result = append(buf.Bytes(), '\n')
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return
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}
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func (p *S) Unmarshal(data []byte) (rem []byte, err error) {
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rem = data
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if p == nil {
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err = errorf.E("can't unmarshal into nil types.T")
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return
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}
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if len(rem) < 2 {
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err = errorf.E("can't unmarshal nothing")
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return
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}
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for i := range rem {
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if rem[i] == '\n' {
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if i != Len {
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err = errorf.E("invalid encoded signature length %d; require %d '%0x'",
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i, Len, rem[:i])
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return
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}
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p.Signature = make([]byte, ed25519.SignatureSize)
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if _, err = base64.RawURLEncoding.Decode(p.Signature, rem[:i]); chk.E(err) {
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return
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}
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rem = rem[i+1:]
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return
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}
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}
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err = io.EOF
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return
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}
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