cmd/meta4-check/main.go

   1 // meta4ra -- Metalink 4.0 utilities
   2 // Copyright (C) 2021-2024 Sergey Matveev <stargrave@stargrave.org>
   3 //
   4 // This program is free software: you can redistribute it and/or modify
   5 // it under the terms of the GNU General Public License as published by
   6 // the Free Software Foundation, version 3 of the License.
   7 //
   8 // This program is distributed in the hope that it will be useful,
   9 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11 // GNU General Public License for more details.
  12 //
  13 // You should have received a copy of the GNU General Public License
  14 // along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15
  16 // Metalink 4.0 checker
  17 package main
  18
  19 import (
  20         "bufio"
  21         "encoding/xml"
  22         "flag"
  23         "fmt"
  24         "io"
  25         "io/fs"
  26         "log"
  27         "os"
  28         "strings"
  29
  30         "go.stargrave.org/meta4ra"
  31 )
  32
  33 func main() {
  34         hashes := flag.String("hashes", strings.Join(meta4ra.HashesDefault, ","), "hash-name:command-s")
  35         extractSig := flag.Bool("extract-sig", false, "Extract signature files")
  36         log.SetFlags(log.Lshortfile)
  37         flag.Parse()
  38         bad := false
  39         for _, metaPath := range flag.Args() {
  40                 data, err := os.ReadFile(metaPath)
  41                 if err != nil {
  42                         log.Fatalln(err)
  43                 }
  44                 var meta meta4ra.Metalink
  45                 err = xml.Unmarshal(data, &meta)
  46                 if err != nil {
  47                         log.Fatalln(err)
  48                 }
  49                 for _, f := range meta.Files {
  50                         for _, sig := range f.Signature {
  51                                 if !*extractSig {
  52                                         continue
  53                                 }
  54                                 var fn string
  55                                 switch sig.MediaType {
  56                                 case meta4ra.SigMediaTypePGP:
  57                                         fn = f.Name + ".asc"
  58                                 case meta4ra.SigMediaTypeSSH:
  59                                         fn = f.Name + ".sig"
  60                                 }
  61                                 if fn == "" {
  62                                         continue
  63                                 }
  64                                 if err = os.WriteFile(
  65                                         fn,
  66                                         []byte(strings.TrimPrefix(sig.Signature, "\n")),
  67                                         fs.FileMode(0666),
  68                                 ); err != nil {
  69                                         fmt.Println("Error:", f.Name, "can not save signature:", err)
  70                                         bad = true
  71                                 }
  72                         }
  73                         hasher := meta4ra.NewHasher(*hashes)
  74                         var hashTheir string
  75                         var hashName string
  76                         for i, name := range hasher.Names {
  77                                 for _, h := range f.Hashes {
  78                                         if h.Type == name {
  79                                                 hasher.Names = []string{name}
  80                                                 hasher.Cmds = append(hasher.Cmds[:0], hasher.Cmds[i])
  81                                                 hasher.Ins = append(hasher.Ins[:0], hasher.Ins[i])
  82                                                 hasher.Outs = append(hasher.Outs[:0], hasher.Outs[i])
  83                                                 hashName = name
  84                                                 hashTheir = h.Hash
  85                                                 goto HashFound
  86                                         }
  87                                 }
  88                         }
  89                         log.Fatalln("no common hashes found for:", f.Name)
  90                 HashFound:
  91                         fd, err := os.Open(f.Name)
  92                         if err != nil {
  93                                 continue
  94                         }
  95                         hasher.Start()
  96                         _, err = io.Copy(hasher, bufio.NewReaderSize(fd, 1<<20))
  97                         fd.Close()
  98                         sums := hasher.Sums()
  99                         if err != nil {
 100                                 fmt.Println("Error:", f.Name, err)
 101                                 bad = true
 102                                 continue
 103                         }
 104                         hashOur := sums[0].Hash
 105                         if hashOur == hashTheir {
 106                                 fmt.Println(f.Name, hashName, "good")
 107                         } else {
 108                                 fmt.Println(
 109                                         "Hash does not match:", f.Name, hashName,
 110                                         "our:", hashOur,
 111                                         "their:", hashTheir,
 112                                 )
 113                                 bad = true
 114                                 continue
 115                         }
 116                 }
 117         }
 118         if bad {
 119                 os.Exit(1)
 120         }
 121 }