pgx/pgproto3/ssl_request.go
Jack Christensen adbb38f298 Do not allow protocol messages larger than ~1GB
The PostgreSQL server will reject messages greater than ~1 GB anyway.
However, worse than that is that a message that is larger than 4 GB
could wrap the 32-bit integer message size and be interpreted by the
server as multiple messages. This could allow a malicious client to
inject arbitrary protocol messages.

https://github.com/jackc/pgx/security/advisories/GHSA-mrww-27vc-gghv
2024-03-04 09:09:29 -06:00

50 lines
1.0 KiB
Go

package pgproto3
import (
"encoding/binary"
"encoding/json"
"errors"
"github.com/jackc/pgx/v5/internal/pgio"
)
const sslRequestNumber = 80877103
type SSLRequest struct {
}
// Frontend identifies this message as sendable by a PostgreSQL frontend.
func (*SSLRequest) Frontend() {}
func (dst *SSLRequest) Decode(src []byte) error {
if len(src) < 4 {
return errors.New("ssl request too short")
}
requestCode := binary.BigEndian.Uint32(src)
if requestCode != sslRequestNumber {
return errors.New("bad ssl request code")
}
return nil
}
// Encode encodes src into dst. dst will include the 4 byte message length.
func (src *SSLRequest) Encode(dst []byte) ([]byte, error) {
dst = pgio.AppendInt32(dst, 8)
dst = pgio.AppendInt32(dst, sslRequestNumber)
return dst, nil
}
// MarshalJSON implements encoding/json.Marshaler.
func (src SSLRequest) MarshalJSON() ([]byte, error) {
return json.Marshal(struct {
Type string
ProtocolVersion uint32
Parameters map[string]string
}{
Type: "SSLRequest",
})
}