+/*
+meta4a -- Metalink 4.0 utility
+Copyright (C) 2021 Sergey Matveev <stargrave@stargrave.org>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, version 3 of the License.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+// Metalink 4.0 utility
+package main
+
+import (
+ "crypto/sha256"
+ "crypto/sha512"
+ "encoding/hex"
+ "encoding/xml"
+ "flag"
+ "io"
+ "io/ioutil"
+ "log"
+ "os"
+ "path/filepath"
+ "time"
+)
+
+const (
+ Generator = "meta4ra/0.1.0"
+ GPGSigMediaType = "application/pgp-signature"
+)
+
+type Metalink struct {
+ XMLName xml.Name `xml:"urn:ietf:params:xml:ns:metalink metalink"`
+ Files []File `xml:"file"`
+ Generator string `xml:"generator,,omitempty"`
+ Published time.Time `xml:"published,,omitempty"`
+}
+
+type File struct {
+ XMLName xml.Name `xml:"file"`
+ Name string `xml:"name,attr"`
+ Description string `xml:"description,,omitempty"`
+ Hashes []Hash `xml:"hash,,omitempty"`
+ MetaURLs []MetaURL `xml:"metaurl,,omitempty"`
+ Signature *Signature `xml:"signature"`
+ Size uint64 `xml:"size,,omitempty"`
+ URLs []URL `xml:"url,,omitempty"`
+}
+
+type URL struct {
+ XMLName xml.Name `xml:"url"`
+ URL string `xml:",chardata"`
+}
+
+type Signature struct {
+ XMLName xml.Name `xml:"signature"`
+ MediaType string `xml:"mediatype,attr"`
+ Signature string `xml:",cdata"`
+}
+
+type Hash struct {
+ XMLName xml.Name `xml:"hash"`
+ Type string `xml:"type,attr"`
+ Hash string `xml:",chardata"`
+}
+
+type MetaURL struct {
+ XMLName xml.Name `xml:"metaurl"`
+ MediaType string `xml:"mediatype,attr"`
+ URL string `xml:",chardata"`
+}
+
+func main() {
+ file := flag.String("file", "", "Path to file")
+ desc := flag.String("desc", "", "Description")
+ sig := flag.String("sig", "", "Path to signature file")
+ torrent := flag.String("torrent", "", "Torrent URL")
+ log.SetFlags(log.Lshortfile)
+ flag.Parse()
+ urls := make([]URL, 0, len(flag.Args()))
+ for _, u := range flag.Args() {
+ urls = append(urls, URL{URL: u})
+ }
+ fd, err := os.Open(*file)
+ if err != nil {
+ log.Fatalln(err)
+ }
+ fi, err := fd.Stat()
+ if err != nil {
+ log.Fatalln(err)
+ }
+ sha256Hasher := sha256.New()
+ sha512Hasher := sha512.New()
+ _, err = io.Copy(io.MultiWriter(sha256Hasher, sha512Hasher), fd)
+ if err != nil {
+ log.Fatalln(err)
+ }
+ f := File{
+ Name: filepath.Base(*file),
+ Description: *desc,
+ Size: uint64(fi.Size()),
+ URLs: urls,
+ Hashes: []Hash{
+ {Type: "sha-256", Hash: hex.EncodeToString(sha256Hasher.Sum(nil))},
+ {Type: "sha-512", Hash: hex.EncodeToString(sha512Hasher.Sum(nil))},
+ },
+ }
+ if *sig != "" {
+ sigData, err := ioutil.ReadFile(*sig)
+ if err != nil {
+ log.Fatalln(err)
+ }
+ f.Signature = &Signature{
+ MediaType: GPGSigMediaType,
+ Signature: "\n" + string(sigData),
+ }
+ }
+ if *torrent != "" {
+ f.MetaURLs = []MetaURL{{MediaType: "torrent", URL: *torrent}}
+ }
+ m := Metalink{
+ Files: []File{f},
+ Generator: Generator,
+ Published: time.Now().UTC().Truncate(time.Second),
+ }
+ out, err := xml.MarshalIndent(&m, "", " ")
+ if err != nil {
+ log.Fatalln(err)
+ }
+ os.Stdout.Write([]byte(xml.Header))
+ os.Stdout.Write(out)
+ os.Stdout.Write([]byte("\n"))
+}