v2ray-core/common/io/reader.go

123 lines
2.9 KiB
Go

package io // import "github.com/v2ray/v2ray-core/common/io"
import (
"io"
"github.com/v2ray/v2ray-core/common/alloc"
"github.com/v2ray/v2ray-core/common/crypto"
"github.com/v2ray/v2ray-core/common/serial"
"github.com/v2ray/v2ray-core/transport"
)
// ReadFrom reads from a reader and put all content to a buffer.
// If buffer is nil, ReadFrom creates a new normal buffer.
func ReadFrom(reader io.Reader, buffer *alloc.Buffer) (*alloc.Buffer, error) {
if buffer == nil {
buffer = alloc.NewBuffer()
}
nBytes, err := reader.Read(buffer.Value)
buffer.Slice(0, nBytes)
return buffer, err
}
type Reader interface {
Read() (*alloc.Buffer, error)
}
type AdaptiveReader struct {
reader io.Reader
allocate func() *alloc.Buffer
isLarge bool
}
func NewAdaptiveReader(reader io.Reader) *AdaptiveReader {
return &AdaptiveReader{
reader: reader,
allocate: alloc.NewBuffer,
isLarge: false,
}
}
func (this *AdaptiveReader) Read() (*alloc.Buffer, error) {
buffer, err := ReadFrom(this.reader, this.allocate())
if buffer.IsFull() && !this.isLarge {
this.allocate = alloc.NewLargeBuffer
this.isLarge = true
} else if !buffer.IsFull() {
this.allocate = alloc.NewBuffer
this.isLarge = false
}
if err != nil {
alloc.Release(buffer)
return nil, err
}
return buffer, nil
}
type ChunkReader struct {
reader io.Reader
}
func NewChunkReader(reader io.Reader) *ChunkReader {
return &ChunkReader{
reader: reader,
}
}
func (this *ChunkReader) Read() (*alloc.Buffer, error) {
buffer := alloc.NewLargeBuffer()
if _, err := io.ReadFull(this.reader, buffer.Value[:2]); err != nil {
alloc.Release(buffer)
return nil, err
}
length := serial.BytesLiteral(buffer.Value[:2]).Uint16Value()
if _, err := io.ReadFull(this.reader, buffer.Value[:length]); err != nil {
alloc.Release(buffer)
return nil, err
}
buffer.Slice(0, int(length))
return buffer, nil
}
type AuthenticationReader struct {
reader Reader
authenticator crypto.Authenticator
authBeforePayload bool
}
func NewAuthenticationReader(reader Reader, auth crypto.Authenticator, authBeforePayload bool) *AuthenticationReader {
return &AuthenticationReader{
reader: reader,
authenticator: auth,
authBeforePayload: authBeforePayload,
}
}
func (this *AuthenticationReader) Read() (*alloc.Buffer, error) {
buffer, err := this.reader.Read()
if err != nil {
alloc.Release(buffer)
return nil, err
}
authSize := this.authenticator.AuthSize()
var authBytes, payloadBytes []byte
if this.authBeforePayload {
authBytes = buffer.Value[:authSize]
payloadBytes = buffer.Value[authSize:]
} else {
payloadBytes = buffer.Value[:authSize]
authBytes = buffer.Value[authSize:]
}
actualAuthBytes := this.authenticator.Authenticate(nil, payloadBytes)
if !serial.BytesLiteral(authBytes).Equals(serial.BytesLiteral(actualAuthBytes)) {
alloc.Release(buffer)
return nil, transport.CorruptedPacket
}
buffer.Value = payloadBytes
return buffer, nil
}