feat(seed): add advanced transfer seed support (OSS/torrent/CAS)

Add unified sharing-seed format library (openlist-sharing-seed v1), standard BT torrent v1 with x-openlist/x-cas extensions, and exact legacy-compatible CAS Base64 payload. Add /fs/seed/{capabilities,generate,parse,convert,rapid_upload,offline_download,update} APIs with hash-matrix driven generation, per-file comments, multi-format output, safe direct/share source embedding, rapid-upload and offline-download fallbacks, and seed sidecar lifecycle for upload/copy/move/rename/remove. Add global and per-storage (inherit/on/off) auto-generation policy, format policies, default hash matrix, site URL and single-file direct-preview settings. Includes security hardening: path traversal checks, SSRF-safe source validation restricted to the configured site, content-write permission checks, offline-download permission checks, and torrent/OSS/CAS parse limits.

Author: PIKACHUIM

internal/bootstrap/data/setting.go

@@ -187,6 +187,12 @@ func InitialSettings() []model.SettingItem {
 		{Key: conf.HandleHookAfterWriting, Value: "false", Type: conf.TypeBool, Group: model.GLOBAL, Flag: model.PRIVATE},
 		{Key: conf.HandleHookRateLimit, Value: "0", Type: conf.TypeNumber, Group: model.GLOBAL, Flag: model.PRIVATE},
 		{Key: conf.IgnoreSystemFiles, Value: "false", Type: conf.TypeBool, Group: model.GLOBAL, Flag: model.PRIVATE, Help: `When enabled, ignores common system files during upload (.DS_Store, desktop.ini, Thumbs.db, and files starting with ._)`},
+		{Key: conf.SeedSiteURL, Value: "", Type: conf.TypeString, Group: model.GLOBAL, Flag: model.PRIVATE, Help: `Public base URL embedded in generated transfer seed sources when configured`},
+		{Key: conf.SeedDefaultHashMatrix, Value: "md5,sha1,sha256", Type: conf.TypeString, Group: model.GLOBAL, Flag: model.PRIVATE},
+		{Key: conf.SeedFormatPolicies, Value: `{"oss":"off","torrent":"off","cas":"off"}`, Type: conf.TypeText, Group: model.GLOBAL, Flag: model.PRIVATE},
+		{Key: conf.SeedDefaultFormat, Value: "oss", Type: conf.TypeSelect, Options: "oss,torrent,cas", Group: model.GLOBAL, Flag: model.PRIVATE},
+		{Key: conf.SeedSingleDirectPreview, Value: "false", Type: conf.TypeBool, Group: model.GLOBAL, Flag: model.PUBLIC},
+		{Key: conf.SeedAutoGeneratePolicy, Value: "off", Type: conf.TypeSelect, Options: "off,on", Group: model.GLOBAL, Flag: model.PRIVATE, Help: `Global upload sidecar policy; storage-specific inheritance can be layered without changing the safe default`},
 
 		// single settings
 		{Key: conf.Token, Value: token, Type: conf.TypeString, Group: model.SINGLE, Flag: model.PRIVATE},

internal/conf/const.go

@@ -60,6 +60,14 @@ const (
 	HandleHookRateLimit     = "handle_hook_rate_limit"
 	IgnoreSystemFiles       = "ignore_system_files"
 
+	// transfer seeds
+	SeedSiteURL             = "seed_site_url"
+	SeedDefaultHashMatrix   = "seed_default_hash_matrix"
+	SeedFormatPolicies      = "seed_format_policies"
+	SeedDefaultFormat       = "seed_default_format"
+	SeedSingleDirectPreview = "seed_single_direct_preview"
+	SeedAutoGeneratePolicy  = "seed_auto_generate_policy"
+
 	// index
 	SearchIndex     = "search_index"
 	AutoUpdateIndex = "auto_update_index"

internal/model/storage.go

@@ -19,6 +19,7 @@ type Storage struct {
 	Disabled            bool      `json:"disabled"` // if disabled
 	DisableIndex        bool      `json:"disable_index"`
 	EnableSign          bool      `json:"enable_sign"`
+	SeedPolicy          string    `json:"seed_policy" gorm:"default:inherit"`
 	Sort
 	Proxy
 }

internal/op/driver.go

@@ -173,6 +173,14 @@ func getMainItems(config driver.Config) []driver.Item {
 		Default:  "false",
 		Required: true,
 	})
+	items = append(items, driver.Item{
+		Name:     "seed_policy",
+		Type:     conf.TypeSelect,
+		Options:  "inherit,on,off",
+		Default:  "inherit",
+		Required: true,
+		Help:     "Override automatic transfer-seed generation for this storage",
+	})
 	return items
 }
 func getAdditionalItems(t reflect.Type, defaultRoot string) []driver.Item {

pkg/torrent/bencode.go

@@ -145,15 +145,24 @@ func bencodeEncodeOrderedDict(w io.Writer, d OrderedDict) error {
 
 // BencodeDecode 从字节数组解码 bencode 数据
 func BencodeDecode(data []byte) (interface{}, error) {
+	if int64(len(data)) > DefaultMaxSeedSize {
+		return nil, fmt.Errorf("bencode: input exceeds %d bytes", DefaultMaxSeedSize)
+	}
 	reader := bytes.NewReader(data)
-	val, err := bencodeDecodeValue(reader)
+	val, err := bencodeDecodeValue(reader, 0)
 	if err != nil {
 		return nil, err
 	}
+	if reader.Len() != 0 {
+		return nil, fmt.Errorf("bencode: trailing data")
+	}
 	return val, nil
 }
 
-func bencodeDecodeValue(r *bytes.Reader) (interface{}, error) {
+func bencodeDecodeValue(r *bytes.Reader, depth int) (interface{}, error) {
+	if depth > DefaultParseLimits().MaxDepth {
+		return nil, fmt.Errorf("bencode: nesting depth exceeds limit")
+	}
 	b, err := r.ReadByte()
 	if err != nil {
 		return nil, err
@@ -163,9 +172,9 @@ func bencodeDecodeValue(r *bytes.Reader) (interface{}, error) {
 	case b == 'i':
 		return bencodeDecodeInt(r)
 	case b == 'l':
-		return bencodeDecodeList(r)
+		return bencodeDecodeList(r, depth+1)
 	case b == 'd':
-		return bencodeDecodeDict(r)
+		return bencodeDecodeDict(r, depth+1)
 	case b >= '0' && b <= '9':
 		r.UnreadByte()
 		return bencodeDecodeString(r)
@@ -218,41 +227,47 @@ func bencodeDecodeString(r *bytes.Reader) ([]byte, error) {
 	return data, nil
 }
 
-func bencodeDecodeList(r *bytes.Reader) ([]interface{}, error) {
+func bencodeDecodeList(r *bytes.Reader, depth int) ([]interface{}, error) {
 	var list []interface{}
 	for {
+		if len(list) >= DefaultMaxSeedFiles*4 {
+			return nil, fmt.Errorf("bencode: list item limit exceeded")
+		}
 		b, err := r.ReadByte()
 		if err != nil {
 			return nil, err
 		}
 		if b == 'e' {
 			return list, nil
 		}
-		r.UnreadByte()
-		val, err := bencodeDecodeValue(r)
+		_ = r.UnreadByte()
+		val, err := bencodeDecodeValue(r, depth)
 		if err != nil {
 			return nil, err
 		}
 		list = append(list, val)
 	}
 }
 
-func bencodeDecodeDict(r *bytes.Reader) (map[string]interface{}, error) {
+func bencodeDecodeDict(r *bytes.Reader, depth int) (map[string]interface{}, error) {
 	dict := make(map[string]interface{})
 	for {
+		if len(dict) >= DefaultMaxSeedFiles*4 {
+			return nil, fmt.Errorf("bencode: dictionary item limit exceeded")
+		}
 		b, err := r.ReadByte()
 		if err != nil {
 			return nil, err
 		}
 		if b == 'e' {
 			return dict, nil
 		}
-		r.UnreadByte()
+		_ = r.UnreadByte()
 		keyBytes, err := bencodeDecodeString(r)
 		if err != nil {
 			return nil, err
 		}
-		val, err := bencodeDecodeValue(r)
+		val, err := bencodeDecodeValue(r, depth)
 		if err != nil {
 			return nil, err
 		}

pkg/torrent/generate.go

@@ -1,8 +1,10 @@
 package torrent
 
 import (
+	"fmt"
 	"io"
 	"os"
+	"path"
 	"strings"
 )
 
@@ -121,3 +123,27 @@ func GenerateFromFileWithCAS(filePath string) ([]byte, error) {
 
 	return GenerateFromReaderWithCAS(f, info.Name(), info.Size(), DefaultPieceSize)
 }
+
+// GenerateSeedFromReader computes the complete OSS hash matrix in one stream pass.
+func GenerateSeedFromReader(reader io.Reader, filePath string, expectedSize, pieceSize int64, createdBy string) (*Seed, error) {
+	if pieceSize <= 0 {
+		pieceSize = DefaultPieceSize
+	}
+	if err := validateRelativeSeedPath(filePath); err != nil {
+		return nil, err
+	}
+	hw := NewHashWriter(pieceSize, pieceSize)
+	if _, err := CopyAndHash(nil, reader, hw); err != nil {
+		return nil, err
+	}
+	hw.Finish()
+	if expectedSize >= 0 && hw.GetTotalWritten() != expectedSize {
+		return nil, fmt.Errorf("stream size mismatch: read %d bytes, expected %d", hw.GetTotalWritten(), expectedSize)
+	}
+	seed := NewSeed(path.Base(filePath), createdBy, pieceSize)
+	seed.Files = []SeedFile{hw.BuildSeedFile(filePath, "")}
+	if err := ValidateSeed(seed, DefaultParseLimits()); err != nil {
+		return nil, err
+	}
+	return seed, nil
+}

pkg/torrent/hash_writer.go

@@ -3,6 +3,7 @@ package torrent
 import (
 	"crypto/md5"
 	"crypto/sha1"
+	"crypto/sha256"
 	"encoding/hex"
 	"fmt"
 	"hash"
@@ -15,10 +16,15 @@ import (
 type HashWriter struct {
 	// 整文件 MD5
 	fileMD5 hash.Hash
+	// fileSHA1 and fileSHA256 complete the portable full-file matrix.
+	fileSHA1   hash.Hash
+	fileSHA256 hash.Hash
 	// 当前分片 MD5
 	sliceMD5 hash.Hash
-	// 当前 piece 的 SHA-1
-	pieceSHA1 hash.Hash
+	// Per-piece hashers are updated in the same pass as whole-file hashes.
+	pieceMD5    hash.Hash
+	pieceSHA1   hash.Hash
+	pieceSHA256 hash.Hash
 
 	// 分片大小（默认 10MB）
 	sliceSize int64
@@ -34,8 +40,12 @@ type HashWriter struct {
 
 	// 每个分片的 MD5（大写十六进制）
 	sliceMD5Hexs []string
-	// 所有 piece 的 SHA-1 哈希拼接
+	// all standard BitTorrent SHA-1 piece hashes concatenated
 	pieceHashes []byte
+	// portable per-file piece matrix
+	pieceMD5Hexs    []string
+	pieceSHA1Hexs   []string
+	pieceSHA256Hexs []string
 }
 
 // NewHashWriter 创建一个新的 HashWriter
@@ -49,11 +59,15 @@ func NewHashWriter(sliceSize, pieceSize int64) *HashWriter {
 		pieceSize = DefaultPieceSize
 	}
 	return &HashWriter{
-		fileMD5:   md5.New(),
-		sliceMD5:  md5.New(),
-		pieceSHA1: sha1.New(),
-		sliceSize: sliceSize,
-		pieceSize: pieceSize,
+		fileMD5:     md5.New(),
+		fileSHA1:    sha1.New(),
+		fileSHA256:  sha256.New(),
+		sliceMD5:    md5.New(),
+		pieceMD5:    md5.New(),
+		pieceSHA1:   sha1.New(),
+		pieceSHA256: sha256.New(),
+		sliceSize:   sliceSize,
+		pieceSize:   pieceSize,
 	}
 }
 
@@ -76,12 +90,14 @@ func (hw *HashWriter) Write(p []byte) (n int, err error) {
 
 		chunk := p[offset : offset+int(canWrite)]
 
-		// 写入整文件 MD5
-		hw.fileMD5.Write(chunk)
-		// 写入当前分片 MD5
-		hw.sliceMD5.Write(chunk)
-		// 写入当前 piece SHA-1
-		hw.pieceSHA1.Write(chunk)
+		// Write all whole-file and boundary-specific hashes in one pass.
+		_, _ = hw.fileMD5.Write(chunk)
+		_, _ = hw.fileSHA1.Write(chunk)
+		_, _ = hw.fileSHA256.Write(chunk)
+		_, _ = hw.sliceMD5.Write(chunk)
+		_, _ = hw.pieceMD5.Write(chunk)
+		_, _ = hw.pieceSHA1.Write(chunk)
+		_, _ = hw.pieceSHA256.Write(chunk)
 
 		hw.sliceWritten += canWrite
 		hw.pieceWritten += canWrite
@@ -112,8 +128,16 @@ func (hw *HashWriter) finishSlice() {
 
 // finishPiece 完成当前 piece 的 SHA-1 计算
 func (hw *HashWriter) finishPiece() {
-	hw.pieceHashes = append(hw.pieceHashes, hw.pieceSHA1.Sum(nil)...)
+	md5Sum := hw.pieceMD5.Sum(nil)
+	sha1Sum := hw.pieceSHA1.Sum(nil)
+	sha256Sum := hw.pieceSHA256.Sum(nil)
+	hw.pieceMD5Hexs = append(hw.pieceMD5Hexs, hex.EncodeToString(md5Sum))
+	hw.pieceSHA1Hexs = append(hw.pieceSHA1Hexs, hex.EncodeToString(sha1Sum))
+	hw.pieceSHA256Hexs = append(hw.pieceSHA256Hexs, hex.EncodeToString(sha256Sum))
+	hw.pieceHashes = append(hw.pieceHashes, sha1Sum...)
+	hw.pieceMD5.Reset()
 	hw.pieceSHA1.Reset()
+	hw.pieceSHA256.Reset()
 	hw.pieceWritten = 0
 }
 
@@ -134,6 +158,50 @@ func (hw *HashWriter) GetFileMD5() string {
 	return strings.ToUpper(hex.EncodeToString(hw.fileMD5.Sum(nil)))
 }
 
+// GetFileSHA1 returns the lowercase whole-file SHA-1 digest.
+func (hw *HashWriter) GetFileSHA1() string {
+	return hex.EncodeToString(hw.fileSHA1.Sum(nil))
+}
+
+// GetFileSHA256 returns the lowercase whole-file SHA-256 digest.
+func (hw *HashWriter) GetFileSHA256() string {
+	return hex.EncodeToString(hw.fileSHA256.Sum(nil))
+}
+
+// GetPieceMD5s returns independent per-file MD5 piece hashes.
+func (hw *HashWriter) GetPieceMD5s() []string {
+	return append([]string(nil), hw.pieceMD5Hexs...)
+}
+
+// GetPieceSHA1s returns independent per-file SHA-1 piece hashes.
+func (hw *HashWriter) GetPieceSHA1s() []string {
+	return append([]string(nil), hw.pieceSHA1Hexs...)
+}
+
+// GetPieceSHA256s returns independent per-file SHA-256 piece hashes.
+func (hw *HashWriter) GetPieceSHA256s() []string {
+	return append([]string(nil), hw.pieceSHA256Hexs...)
+}
+
+// BuildSeedFile exports all hashes accumulated during this single stream pass.
+func (hw *HashWriter) BuildSeedFile(filePath string, modified string) SeedFile {
+	return SeedFile{
+		Path:     filePath,
+		Size:     hw.totalWritten,
+		Modified: modified,
+		Hashes: SeedHashes{
+			MD5:    strings.ToLower(hw.GetFileMD5()),
+			SHA1:   hw.GetFileSHA1(),
+			SHA256: hw.GetFileSHA256(),
+			Pieces: &SeedPieceHashes{
+				MD5:    hw.GetPieceMD5s(),
+				SHA1:   hw.GetPieceSHA1s(),
+				SHA256: hw.GetPieceSHA256s(),
+			},
+		},
+	}
+}
+
 // GetSliceMD5s 获取所有分片的 MD5 列表
 func (hw *HashWriter) GetSliceMD5s() []string {
 	return hw.sliceMD5Hexs