Files
realy/bech32encoding/nip19.go
2025-02-08 12:45:28 -01:06

234 lines
6.3 KiB
Go

package bech32encoding
import (
"bytes"
"encoding/binary"
"reflect"
"realy.lol/bech32encoding/pointers"
"realy.lol/ec/bech32"
"realy.lol/ec/schnorr"
"realy.lol/eventid"
"realy.lol/hex"
"realy.lol/kind"
"realy.lol/sha256"
)
var (
NoteHRP = []byte("note")
NsecHRP = []byte("nsec")
NpubHRP = []byte("npub")
NprofileHRP = []byte("nprofile")
NeventHRP = []byte("nevent")
NentityHRP = []byte("naddr")
)
func DecodeToString(bech32String []byte) (prefix, value []byte, err error) {
var s any
if prefix, s, err = Decode(bech32String); chk.D(err) {
return
}
var ok bool
if value, ok = s.([]byte); ok {
return
}
err = log.E.Err("value was not decoded to a string, found type %s",
reflect.TypeOf(s))
return
}
func Decode(bech32string []byte) (prefix []byte, value any, err error) {
var bits5 []byte
if prefix, bits5, err = bech32.DecodeNoLimit(bech32string); chk.D(err) {
return
}
var data []byte
if data, err = bech32.ConvertBits(bits5, 5, 8, false); chk.D(err) {
return prefix, nil, errorf.E("failed translating data into 8 bits: %s", err.Error())
}
switch {
case bytes.Equal(prefix, NpubHRP) ||
bytes.Equal(prefix, NsecHRP) ||
bytes.Equal(prefix, NoteHRP):
if len(data) < 32 {
return prefix, nil, errorf.E("data is less than 32 bytes (%d)", len(data))
}
b := make([]byte, schnorr.PubKeyBytesLen*2)
hex.EncBytes(b, data[:32])
return prefix, b, nil
case bytes.Equal(prefix, NprofileHRP):
var result pointers.Profile
curr := 0
for {
t, v := readTLVEntry(data[curr:])
if v == nil {
// end here
if len(result.PublicKey) < 1 {
return prefix, result, errorf.E("no pubkey found for nprofile")
}
return prefix, result, nil
}
switch t {
case TLVDefault:
if len(v) < 32 {
return prefix, nil, errorf.E("pubkey is less than 32 bytes (%d)", len(v))
}
result.PublicKey = make([]byte, schnorr.PubKeyBytesLen*2)
hex.EncBytes(result.PublicKey, v)
case TLVRelay:
result.Relays = append(result.Relays, v)
default:
// ignore
}
curr = curr + 2 + len(v)
}
case bytes.Equal(prefix, NeventHRP):
var result pointers.Event
curr := 0
for {
t, v := readTLVEntry(data[curr:])
if v == nil {
// end here
if result.ID.Len() == 0 {
return prefix, result, errorf.E("no id found for nevent")
}
return prefix, result, nil
}
switch t {
case TLVDefault:
if len(v) < 32 {
return prefix, nil, errorf.E("id is less than 32 bytes (%d)", len(v))
}
result.ID = eventid.NewWith(v)
case TLVRelay:
result.Relays = append(result.Relays, v)
case TLVAuthor:
if len(v) < 32 {
return prefix, nil, errorf.E("author is less than 32 bytes (%d)", len(v))
}
result.Author = make([]byte, schnorr.PubKeyBytesLen*2)
hex.EncBytes(result.Author, v)
case TLVKind:
result.Kind = kind.New(binary.BigEndian.Uint32(v))
default:
// ignore
}
curr = curr + 2 + len(v)
}
case bytes.Equal(prefix, NentityHRP):
var result pointers.Entity
curr := 0
for {
t, v := readTLVEntry(data[curr:])
if v == nil {
// end here
if result.Kind.ToU16() == 0 ||
len(result.Identifier) < 1 ||
len(result.PublicKey) < 1 {
return prefix, result, errorf.E("incomplete naddr")
}
return prefix, result, nil
}
switch t {
case TLVDefault:
result.Identifier = v
case TLVRelay:
result.Relays = append(result.Relays, v)
case TLVAuthor:
if len(v) < 32 {
return prefix, nil, errorf.E("author is less than 32 bytes (%d)", len(v))
}
result.PublicKey = make([]byte, schnorr.PubKeyBytesLen*2)
hex.EncBytes(result.PublicKey, v)
case TLVKind:
result.Kind = kind.New(binary.BigEndian.Uint32(v))
default:
log.D.Ln("got a bogus TLV type code", t)
// ignore
}
curr = curr + 2 + len(v)
}
}
return prefix, data, errorf.E("unknown tag %s", prefix)
}
func EncodeNote(eventIDHex []byte) (s []byte, err error) {
var b []byte
if _, err = hex.DecBytes(b, eventIDHex); chk.D(err) {
err = log.E.Err("failed to decode event id hex: %w", err)
return
}
var bits5 []byte
if bits5, err = bech32.ConvertBits(b, 8, 5, true); chk.D(err) {
return
}
return bech32.Encode(NoteHRP, bits5)
}
func EncodeProfile(publicKeyHex []byte, relays [][]byte) (s []byte, err error) {
buf := &bytes.Buffer{}
pb := make([]byte, schnorr.PubKeyBytesLen)
if _, err = hex.DecBytes(pb, publicKeyHex); chk.D(err) {
err = log.E.Err("invalid pubkey '%s': %w", publicKeyHex, err)
return
}
writeTLVEntry(buf, TLVDefault, pb)
for _, url := range relays {
writeTLVEntry(buf, TLVRelay, []byte(url))
}
var bits5 []byte
if bits5, err = bech32.ConvertBits(buf.Bytes(), 8, 5, true); chk.D(err) {
err = log.E.Err("failed to convert bits: %w", err)
return
}
return bech32.Encode(NprofileHRP, bits5)
}
func EncodeEvent(eventIDHex *eventid.T, relays [][]byte, author []byte) (s []byte, err error) {
buf := &bytes.Buffer{}
id := make([]byte, sha256.Size)
if _, err = hex.DecBytes(id, eventIDHex.ByteString(nil)); chk.D(err) ||
len(id) != 32 {
return nil, errorf.E("invalid id %d '%s': %v", len(id), eventIDHex,
err)
}
writeTLVEntry(buf, TLVDefault, id)
for _, url := range relays {
writeTLVEntry(buf, TLVRelay, []byte(url))
}
pubkey := make([]byte, schnorr.PubKeyBytesLen)
if _, err = hex.DecBytes(pubkey, author); len(pubkey) == 32 {
writeTLVEntry(buf, TLVAuthor, pubkey)
}
var bits5 []byte
if bits5, err = bech32.ConvertBits(buf.Bytes(), 8, 5, true); chk.D(err) {
err = log.E.Err("failed to convert bits: %w", err)
return
}
return bech32.Encode(NeventHRP, bits5)
}
func EncodeEntity(pk []byte, k *kind.T, id []byte, relays [][]byte) (s []byte, err error) {
buf := &bytes.Buffer{}
writeTLVEntry(buf, TLVDefault, []byte(id))
for _, url := range relays {
writeTLVEntry(buf, TLVRelay, []byte(url))
}
pb := make([]byte, schnorr.PubKeyBytesLen)
if _, err = hex.DecBytes(pb, pk); chk.D(err) {
return nil, errorf.E("invalid pubkey '%s': %w", pb, err)
}
writeTLVEntry(buf, TLVAuthor, pb)
kindBytes := make([]byte, 4)
binary.BigEndian.PutUint32(kindBytes, uint32(k.ToU16()))
writeTLVEntry(buf, TLVKind, kindBytes)
var bits5 []byte
if bits5, err = bech32.ConvertBits(buf.Bytes(), 8, 5, true); chk.D(err) {
return nil, errorf.E("failed to convert bits: %w", err)
}
return bech32.Encode(NentityHRP, bits5)
}