From 97bde62236121bfee5c5cca0419be1db1f19fc53 Mon Sep 17 00:00:00 2001 From: Evan Su <48808396+HACKERALERT@users.noreply.github.com> Date: Thu, 25 Apr 2024 22:07:05 -0400 Subject: [PATCH] Add -fix flag, use fast RS by default --- cli/v2/picocrypt/main.go | 40 ++++++++++++++++++++++++++-------------- 1 file changed, 26 insertions(+), 14 deletions(-) diff --git a/cli/v2/picocrypt/main.go b/cli/v2/picocrypt/main.go index c703867..161f055 100644 --- a/cli/v2/picocrypt/main.go +++ b/cli/v2/picocrypt/main.go @@ -47,7 +47,10 @@ func rsEncode(rs *infectious.FEC, data []byte) []byte { return res } -func rsDecode(rs *infectious.FEC, data []byte) ([]byte, error) { +func rsDecode(rs *infectious.FEC, data []byte, fast bool) ([]byte, error) { + if rs.Total() == 136 && fast { + return data[:128], nil + } tmp := make([]infectious.Share, rs.Total()) for i := 0; i < rs.Total(); i++ { tmp[i].Number = i @@ -81,6 +84,7 @@ func work() int { } paranoid := flag.Bool("p", false, "") reedsolo := flag.Bool("r", false, "") + fix := flag.Bool("fix", false, "") flag.Parse() mode := "" @@ -327,16 +331,16 @@ func work() int { errs := make([]error, 10) version := make([]byte, 15) fin.Read(version) - _, errs[0] = rsDecode(rs5, version) + _, errs[0] = rsDecode(rs5, version, !(*fix)) tmp := make([]byte, 15) fin.Read(tmp) - tmp, errs[1] = rsDecode(rs5, tmp) + tmp, errs[1] = rsDecode(rs5, tmp, !(*fix)) commentsLength, _ := strconv.Atoi(string(tmp)) fin.Read(make([]byte, commentsLength*3)) total -= int64(commentsLength) * 3 flags := make([]byte, 15) fin.Read(flags) - flags, errs[2] = rsDecode(rs5, flags) + flags, errs[2] = rsDecode(rs5, flags, !(*fix)) *paranoid = flags[0] == 1 *reedsolo = flags[3] == 1 padded = flags[4] == 1 @@ -349,25 +353,25 @@ func work() int { } salt = make([]byte, 48) fin.Read(salt) - salt, errs[3] = rsDecode(rs16, salt) + salt, errs[3] = rsDecode(rs16, salt, !(*fix)) hkdfSalt = make([]byte, 96) fin.Read(hkdfSalt) - hkdfSalt, errs[4] = rsDecode(rs32, hkdfSalt) + hkdfSalt, errs[4] = rsDecode(rs32, hkdfSalt, !(*fix)) serpentIV = make([]byte, 48) fin.Read(serpentIV) - serpentIV, errs[5] = rsDecode(rs16, serpentIV) + serpentIV, errs[5] = rsDecode(rs16, serpentIV, !(*fix)) nonce = make([]byte, 72) fin.Read(nonce) - nonce, errs[6] = rsDecode(rs24, nonce) + nonce, errs[6] = rsDecode(rs24, nonce, !(*fix)) keyHashRef = make([]byte, 192) fin.Read(keyHashRef) - keyHashRef, errs[7] = rsDecode(rs64, keyHashRef) + keyHashRef, errs[7] = rsDecode(rs64, keyHashRef, !(*fix)) keyfileHashRef := make([]byte, 96) fin.Read(keyfileHashRef) - _, errs[8] = rsDecode(rs32, keyfileHashRef) + _, errs[8] = rsDecode(rs32, keyfileHashRef, !(*fix)) authTag = make([]byte, 192) fin.Read(authTag) - authTag, errs[9] = rsDecode(rs64, authTag) + authTag, errs[9] = rsDecode(rs64, authTag, !(*fix)) for _, err := range errs { if err != nil { fin.Close() @@ -487,7 +491,7 @@ func work() int { src = nil if len(dst) == MiB/128*136 { for i := 0; i < MiB/128*136; i += 136 { - tmp, err := rsDecode(rs128, dst[i:i+136]) + tmp, err := rsDecode(rs128, dst[i:i+136], !(*fix)) if err != nil { fin.Close() fout.Close() @@ -503,7 +507,7 @@ func work() int { } else { chunks := len(dst)/136 - 1 for i := 0; i < chunks; i++ { - tmp, err := rsDecode(rs128, dst[i*136:(i+1)*136]) + tmp, err := rsDecode(rs128, dst[i*136:(i+1)*136], !(*fix)) if err != nil { fin.Close() fout.Close() @@ -513,7 +517,7 @@ func work() int { } src = append(src, tmp...) } - tmp, err := rsDecode(rs128, dst[int(chunks)*136:]) + tmp, err := rsDecode(rs128, dst[int(chunks)*136:], !(*fix)) if err != nil { fin.Close() fout.Close() @@ -571,6 +575,14 @@ func work() int { fout.Close() os.Remove(fout_) fmt.Println("The input volume is damaged or modified.") + if *reedsolo { + if !(*fix) { + fmt.Println("Fortunately, this volume is encoded with Reed-Solomon.") + fmt.Println("Try again using the -fix flag to repair the corruption.") + } else { + fmt.Println("The corruption could not be fixed with Reed-Solomon.") + } + } return 1 } }