mirror of
https://github.com/go-gitea/gitea.git
synced 2024-12-28 06:46:29 +08:00
274149dd14
* Switch to keybase go-crypto (for some elliptic curve key) + test
* Use assert.NoError
and add a little more context to failing test description
* Use assert.(No)Error everywhere 🌈
and assert.Error in place of .Nil/.NotNil
77 lines
2.2 KiB
Go
77 lines
2.2 KiB
Go
// Copyright 2011 The Go Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
package packet
|
|
|
|
import (
|
|
"io"
|
|
|
|
"github.com/keybase/go-crypto/openpgp/errors"
|
|
)
|
|
|
|
// Reader reads packets from an io.Reader and allows packets to be 'unread' so
|
|
// that they result from the next call to Next.
|
|
type Reader struct {
|
|
q []Packet
|
|
readers []io.Reader
|
|
}
|
|
|
|
// New io.Readers are pushed when a compressed or encrypted packet is processed
|
|
// and recursively treated as a new source of packets. However, a carefully
|
|
// crafted packet can trigger an infinite recursive sequence of packets. See
|
|
// http://mumble.net/~campbell/misc/pgp-quine
|
|
// https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2013-4402
|
|
// This constant limits the number of recursive packets that may be pushed.
|
|
const maxReaders = 32
|
|
|
|
// Next returns the most recently unread Packet, or reads another packet from
|
|
// the top-most io.Reader. Unknown packet types are skipped.
|
|
func (r *Reader) Next() (p Packet, err error) {
|
|
if len(r.q) > 0 {
|
|
p = r.q[len(r.q)-1]
|
|
r.q = r.q[:len(r.q)-1]
|
|
return
|
|
}
|
|
|
|
for len(r.readers) > 0 {
|
|
p, err = Read(r.readers[len(r.readers)-1])
|
|
if err == nil {
|
|
return
|
|
}
|
|
if err == io.EOF {
|
|
r.readers = r.readers[:len(r.readers)-1]
|
|
continue
|
|
}
|
|
if _, ok := err.(errors.UnknownPacketTypeError); !ok {
|
|
return nil, err
|
|
}
|
|
}
|
|
return nil, io.EOF
|
|
}
|
|
|
|
// Push causes the Reader to start reading from a new io.Reader. When an EOF
|
|
// error is seen from the new io.Reader, it is popped and the Reader continues
|
|
// to read from the next most recent io.Reader. Push returns a StructuralError
|
|
// if pushing the reader would exceed the maximum recursion level, otherwise it
|
|
// returns nil.
|
|
func (r *Reader) Push(reader io.Reader) (err error) {
|
|
if len(r.readers) >= maxReaders {
|
|
return errors.StructuralError("too many layers of packets")
|
|
}
|
|
r.readers = append(r.readers, reader)
|
|
return nil
|
|
}
|
|
|
|
// Unread causes the given Packet to be returned from the next call to Next.
|
|
func (r *Reader) Unread(p Packet) {
|
|
r.q = append(r.q, p)
|
|
}
|
|
|
|
func NewReader(r io.Reader) *Reader {
|
|
return &Reader{
|
|
q: nil,
|
|
readers: []io.Reader{r},
|
|
}
|
|
}
|