cmd/meta4ra/check.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 package main
  17
  18 import (
  19         "bufio"
  20         "encoding/xml"
  21         "flag"
  22         "fmt"
  23         "io"
  24         "io/fs"
  25         "log"
  26         "os"
  27         "path"
  28         "strings"
  29
  30         meta4ra "go.stargrave.org/meta4ra/internal"
  31 )
  32
  33 func runCheck() {
  34         pipe := flag.Bool("pipe", false, "Verify file data from stdin, copy to stdout")
  35         allHashes := flag.Bool("all-hashes", false, "Check all hashes, not the first common one")
  36         hashes := flag.String("hashes", meta4ra.HashesDefault,
  37                 "hash-name:commandline[,...]")
  38         extractSig := flag.Bool("extract-sig", false, "Extract signature files")
  39         metaPath := flag.String("meta4", "file.meta4", "Metalink file")
  40         flag.Usage = func() {
  41                 fmt.Fprintf(flag.CommandLine.Output(),
  42                         "Usage: %s [options] [FILE ...]\n", os.Args[0])
  43                 flag.PrintDefaults()
  44                 fmt.Fprint(flag.CommandLine.Output(), `
  45 If no FILEs are specified, then all <file>s from metalink are searched and
  46 verified if they exist. Otherwise only specified FILEs are checked. If you
  47 want to skip any <file> verification (for example only to validate the format
  48 and -extract-sig, then you can just specify an empty ("") FILE.
  49 `)
  50         }
  51         flag.Parse()
  52
  53         if *showVersion {
  54                 fmt.Println(meta4ra.Version())
  55                 return
  56         }
  57         if *showWarranty {
  58                 fmt.Println(meta4ra.Warranty)
  59                 return
  60         }
  61
  62         data, err := os.ReadFile(*metaPath)
  63         if err != nil {
  64                 log.Fatalln(err)
  65         }
  66         var meta meta4ra.Metalink
  67         err = xml.Unmarshal(data, &meta)
  68         if err != nil {
  69                 log.Fatalln(err)
  70         }
  71
  72         toCheck := make(map[string]string)
  73         for _, fn := range flag.Args() {
  74                 toCheck[path.Base(fn)] = fn
  75         }
  76         if *pipe && len(toCheck) != 1 {
  77                 log.Fatalln("exactly single FILE must be specified when using -pipe")
  78         }
  79
  80         bad := false
  81         for _, f := range meta.Files {
  82                 for _, sig := range f.Signature {
  83                         if !*extractSig {
  84                                 continue
  85                         }
  86                         var fn string
  87                         switch sig.MediaType {
  88                         case meta4ra.SigMediaTypePGP:
  89                                 fn = f.Name + ".asc"
  90                         case meta4ra.SigMediaTypeSSH:
  91                                 fn = f.Name + ".sig"
  92                         }
  93                         if fn == "" {
  94                                 continue
  95                         }
  96                         if err = os.WriteFile(
  97                                 fn,
  98                                 []byte(strings.TrimPrefix(sig.Signature, "\n")),
  99                                 fs.FileMode(0666),
 100                         ); err != nil {
 101                                 log.Println("Error:", f.Name, "can not save signature:", err)
 102                                 bad = true
 103                         }
 104                 }
 105
 106                 fullPath := toCheck[f.Name]
 107                 delete(toCheck, f.Name)
 108                 if !(len(toCheck) == 0 || fullPath != "") {
 109                         continue
 110                 }
 111                 if fullPath == "" {
 112                         fullPath = f.Name
 113                 }
 114                 if !*pipe {
 115                         s, err := os.Stat(fullPath)
 116                         if err != nil {
 117                                 log.Println(err)
 118                                 bad = true
 119                                 continue
 120                         }
 121                         if uint64(s.Size()) != f.Size {
 122                                 log.Println("size mismatch",
 123                                         f.Name, "our:", s.Size(), "their:", f.Size)
 124                                 bad = true
 125                                 continue
 126                         }
 127                 }
 128
 129                 hasher, err := meta4ra.NewHasher(*hashes)
 130                 if err != nil {
 131                         log.Println(f.Name, err)
 132                         bad = true
 133                         continue
 134                 }
 135                 var hashTheir string
 136                 var hashName string
 137                 if *allHashes {
 138                         goto HashFound
 139                 }
 140                 for i, name := range hasher.Names {
 141                         for _, h := range f.Hashes {
 142                                 if h.Type == name {
 143                                         hasher.Names = []string{name}
 144                                         hasher.Cmds = append(hasher.Cmds[:0], hasher.Cmds[i])
 145                                         hasher.Ins = append(hasher.Ins[:0], hasher.Ins[i])
 146                                         hasher.Outs = append(hasher.Outs[:0], hasher.Outs[i])
 147                                         hashName = name
 148                                         hashTheir = h.Hash
 149                                         goto HashFound
 150                                 }
 151                         }
 152                 }
 153                 log.Println("no common hashes found for:", f.Name)
 154                 bad = true
 155                 continue
 156         HashFound:
 157
 158                 fd := os.Stdin
 159                 if !*pipe {
 160                         fd, err = os.Open(fullPath)
 161                         if err != nil {
 162                                 log.Println("Error:", f.Name, err)
 163                                 bad = true
 164                                 continue
 165                         }
 166                 }
 167                 err = hasher.Start()
 168                 if err != nil {
 169                         if !*pipe {
 170                                 fd.Close()
 171                         }
 172                         hasher.Stop()
 173                         log.Println("Error:", f.Name, err)
 174                         bad = true
 175                         continue
 176                 }
 177                 var w io.Writer
 178                 if *pipe {
 179                         w = io.MultiWriter(os.Stdout, hasher)
 180                 } else {
 181                         w = hasher
 182                 }
 183                 _, err = io.Copy(w, bufio.NewReaderSize(fd, meta4ra.BufLen))
 184                 if !*pipe {
 185                         fd.Close()
 186                 }
 187                 if err != nil {
 188                         hasher.Stop()
 189                         log.Println("Error:", f.Name, err)
 190                         bad = true
 191                         continue
 192                 }
 193                 sums, err := hasher.Sums()
 194                 if err != nil {
 195                         hasher.Stop()
 196                         log.Println("Error:", f.Name, err)
 197                         bad = true
 198                         continue
 199                 }
 200                 if *allHashes {
 201                         hashesOur := make(map[string]string, len(sums))
 202                         for _, h := range sums {
 203                                 hashesOur[h.Type] = h.Hash
 204                         }
 205                         for _, h := range f.Hashes {
 206                                 hashOur := hashesOur[h.Type]
 207                                 if h.Hash == hashOur {
 208                                         if !*pipe {
 209                                                 fmt.Fprintln(os.Stderr, f.Name, h.Type, "good")
 210                                         }
 211                                 } else {
 212                                         log.Println(
 213                                                 "hash mismatch:", f.Name, h.Type,
 214                                                 "our:", hashOur,
 215                                                 "their:", h.Hash,
 216                                         )
 217                                         bad = true
 218                                 }
 219                         }
 220                 } else {
 221                         hashOur := sums[0].Hash
 222                         if hashOur == hashTheir {
 223                                 if !*pipe {
 224                                         fmt.Fprintln(os.Stderr, f.Name, hashName, "good")
 225                                 }
 226                         } else {
 227                                 log.Println(
 228                                         "hash mismatch:", f.Name, hashName,
 229                                         "our:", hashOur,
 230                                         "their:", hashTheir,
 231                                 )
 232                                 bad = true
 233                                 continue
 234                         }
 235                 }
 236         }
 237         if len(toCheck) != 0 {
 238                 if _, ok := toCheck["."]; !(len(toCheck) == 1 && ok) {
 239                         log.Println("not all FILEs met")
 240                         bad = true
 241                 }
 242         }
 243         if bad {
 244                 os.Exit(1)
 245         }
 246 }