// Copyright 2023 The Gitea Authors. All rights reserved.// SPDX-License-Identifier: MIT package git import ( "crypto/sha1" "crypto/sha256" "hash" "regexp" "strconv") // sha1Pattern can be used to determine if a string is an valid shavar sha1Pattern = regexp.MustCompile(`^[0-9a-f]{4,40}$`) // sha256Pattern can be used to determine if a string is an valid shavar sha256Pattern = regexp.MustCompile(`^[0-9a-f]{4,64}$`) type ObjectFormat interface { // Name returns the name of the object format Name() string // EmptyObjectID creates a new empty ObjectID from an object format hash name EmptyObjectID() ObjectID // EmptyTree is the hash of an empty tree EmptyTree() ObjectID // FullLength is the length of the hash's hex string FullLength() int // IsValid returns true if the input is a valid hash IsValid(input string) bool // MustID creates a new ObjectID from a byte slice MustID(b []byte) ObjectID // ComputeHash compute the hash for a given ObjectType and content ComputeHash(t ObjectType, content []byte) ObjectID} func computeHash(dst []byte, hasher hash.Hash, t ObjectType, content []byte) []byte { _, _ = hasher.Write(t.Bytes()) _, _ = hasher.Write([]byte(" ")) _, _ = hasher.Write([]byte(strconv.Itoa(len(content)))) _, _ = hasher.Write([]byte{0}) _, _ = hasher.Write(content) return hasher.Sum(dst)} /* SHA1 Type */type Sha1ObjectFormatImpl struct{} var ( emptySha1ObjectID = &Sha1Hash{} emptySha1Tree = &Sha1Hash{ 0x4b, 0x82, 0x5d, 0xc6, 0x42, 0xcb, 0x6e, 0xb9, 0xa0, 0x60, 0xe5, 0x4b, 0xf8, 0xd6, 0x92, 0x88, 0xfb, 0xee, 0x49, 0x04, }) func (Sha1ObjectFormatImpl) Name() string { return "sha1" }func (Sha1ObjectFormatImpl) EmptyObjectID() ObjectID { return emptySha1ObjectID} func (Sha1ObjectFormatImpl) EmptyTree() ObjectID { return emptySha1Tree}func (Sha1ObjectFormatImpl) FullLength() int { return 40 }func (Sha1ObjectFormatImpl) IsValid(input string) bool { return sha1Pattern.MatchString(input)} func (Sha1ObjectFormatImpl) MustID(b []byte) ObjectID { var id Sha1Hash copy(id[0:20], b) return &id} // ComputeHash compute the hash for a given ObjectType and contentfunc (h Sha1ObjectFormatImpl) ComputeHash(t ObjectType, content []byte) ObjectID { var obj Sha1Hash computeHash(obj[:0], sha1.New(), t, content) return &obj} /* SHA256 Type */type Sha256ObjectFormatImpl struct{} var ( emptySha256ObjectID = &Sha256Hash{} emptySha256Tree = &Sha256Hash{ 0x6e, 0xf1, 0x9b, 0x41, 0x22, 0x5c, 0x53, 0x69, 0xf1, 0xc1, 0x04, 0xd4, 0x5d, 0x8d, 0x85, 0xef, 0xa9, 0xb0, 0x57, 0xb5, 0x3b, 0x14, 0xb4, 0xb9, 0xb9, 0x39, 0xdd, 0x74, 0xde, 0xcc, 0x53, 0x21, }) func (Sha256ObjectFormatImpl) Name() string { return "sha256" }func (Sha256ObjectFormatImpl) EmptyObjectID() ObjectID { return emptySha256ObjectID} func (Sha256ObjectFormatImpl) EmptyTree() ObjectID { return emptySha256Tree}func (Sha256ObjectFormatImpl) FullLength() int { return 64 }func (Sha256ObjectFormatImpl) IsValid(input string) bool { return sha256Pattern.MatchString(input)} func (Sha256ObjectFormatImpl) MustID(b []byte) ObjectID { var id Sha256Hash copy(id[0:32], b) return &id} // ComputeHash compute the hash for a given ObjectType and contentfunc (h Sha256ObjectFormatImpl) ComputeHash(t ObjectType, content []byte) ObjectID { var obj Sha256Hash computeHash(obj[:0], sha256.New(), t, content) return &obj} var ( Sha1ObjectFormat ObjectFormat = Sha1ObjectFormatImpl{} Sha256ObjectFormat ObjectFormat = Sha256ObjectFormatImpl{}) var SupportedObjectFormats = []ObjectFormat{ Sha1ObjectFormat,} func ObjectFormatFromName(name string) ObjectFormat { for _, objectFormat := range SupportedObjectFormats { if name == objectFormat.Name() { return objectFormat } } return nil} func IsValidObjectFormat(name string) bool { return ObjectFormatFromName(name) != nil}
// Copyright 2023 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package git
import (
"crypto/sha1"
"crypto/sha256"
"hash"
"regexp"
"strconv"
)
// sha1Pattern can be used to determine if a string is an valid sha
var sha1Pattern = regexp.MustCompile(`^[0-9a-f]{4,40}$`)
// sha256Pattern can be used to determine if a string is an valid sha
var sha256Pattern = regexp.MustCompile(`^[0-9a-f]{4,64}$`)
type ObjectFormat interface {
// Name returns the name of the object format
Name() string
// EmptyObjectID creates a new empty ObjectID from an object format hash name
EmptyObjectID() ObjectID
// EmptyTree is the hash of an empty tree
EmptyTree() ObjectID
// FullLength is the length of the hash's hex string
FullLength() int
// IsValid returns true if the input is a valid hash
IsValid(input string) bool
// MustID creates a new ObjectID from a byte slice
MustID(b []byte) ObjectID
// ComputeHash compute the hash for a given ObjectType and content
ComputeHash(t ObjectType, content []byte) ObjectID
}
func computeHash(dst []byte, hasher hash.Hash, t ObjectType, content []byte) []byte {
_, _ = hasher.Write(t.Bytes())
_, _ = hasher.Write([]byte(" "))
_, _ = hasher.Write([]byte(strconv.Itoa(len(content))))
_, _ = hasher.Write([]byte{0})
_, _ = hasher.Write(content)
return hasher.Sum(dst)
}
/* SHA1 Type */
type Sha1ObjectFormatImpl struct{}
var (
emptySha1ObjectID = &Sha1Hash{}
emptySha1Tree = &Sha1Hash{
0x4b, 0x82, 0x5d, 0xc6, 0x42, 0xcb, 0x6e, 0xb9, 0xa0, 0x60,
0xe5, 0x4b, 0xf8, 0xd6, 0x92, 0x88, 0xfb, 0xee, 0x49, 0x04,
}
)
func (Sha1ObjectFormatImpl) Name() string { return "sha1" }
func (Sha1ObjectFormatImpl) EmptyObjectID() ObjectID {
return emptySha1ObjectID
}
func (Sha1ObjectFormatImpl) EmptyTree() ObjectID {
return emptySha1Tree
}
func (Sha1ObjectFormatImpl) FullLength() int { return 40 }
func (Sha1ObjectFormatImpl) IsValid(input string) bool {
return sha1Pattern.MatchString(input)
}
func (Sha1ObjectFormatImpl) MustID(b []byte) ObjectID {
var id Sha1Hash
copy(id[0:20], b)
return &id
}
// ComputeHash compute the hash for a given ObjectType and content
func (h Sha1ObjectFormatImpl) ComputeHash(t ObjectType, content []byte) ObjectID {
var obj Sha1Hash
computeHash(obj[:0], sha1.New(), t, content)
return &obj
}
/* SHA256 Type */
type Sha256ObjectFormatImpl struct{}
var (
emptySha256ObjectID = &Sha256Hash{}
emptySha256Tree = &Sha256Hash{
0x6e, 0xf1, 0x9b, 0x41, 0x22, 0x5c, 0x53, 0x69, 0xf1, 0xc1,
0x04, 0xd4, 0x5d, 0x8d, 0x85, 0xef, 0xa9, 0xb0, 0x57, 0xb5,
0x3b, 0x14, 0xb4, 0xb9, 0xb9, 0x39, 0xdd, 0x74, 0xde, 0xcc,
0x53, 0x21,
}
)
func (Sha256ObjectFormatImpl) Name() string { return "sha256" }
func (Sha256ObjectFormatImpl) EmptyObjectID() ObjectID {
return emptySha256ObjectID
}
func (Sha256ObjectFormatImpl) EmptyTree() ObjectID {
return emptySha256Tree
}
func (Sha256ObjectFormatImpl) FullLength() int { return 64 }
func (Sha256ObjectFormatImpl) IsValid(input string) bool {
return sha256Pattern.MatchString(input)
}
func (Sha256ObjectFormatImpl) MustID(b []byte) ObjectID {
var id Sha256Hash
copy(id[0:32], b)
return &id
}
// ComputeHash compute the hash for a given ObjectType and content
func (h Sha256ObjectFormatImpl) ComputeHash(t ObjectType, content []byte) ObjectID {
var obj Sha256Hash
computeHash(obj[:0], sha256.New(), t, content)
return &obj
}
var (
Sha1ObjectFormat ObjectFormat = Sha1ObjectFormatImpl{}
Sha256ObjectFormat ObjectFormat = Sha256ObjectFormatImpl{}
)
var SupportedObjectFormats = []ObjectFormat{
Sha1ObjectFormat,
}
func ObjectFormatFromName(name string) ObjectFormat {
for _, objectFormat := range SupportedObjectFormats {
if name == objectFormat.Name() {
return objectFormat
}
}
return nil
}
func IsValidObjectFormat(name string) bool {
return ObjectFormatFromName(name) != nil
}