32 lines
853 B
Go
32 lines
853 B
Go
package xt
|
|
|
|
import (
|
|
"bytes"
|
|
"fmt"
|
|
)
|
|
|
|
// CommentSize is the fixed size of a comment info xt blob.
|
|
const CommentSize = 256
|
|
|
|
// Comment gets marshalled and unmarshalled as a fixed-sized char array, filled
|
|
// with zeros as necessary, see:
|
|
// https://elixir.bootlin.com/linux/v6.8.7/source/include/uapi/linux/netfilter/xt_comment.h#L7
|
|
type Comment string
|
|
|
|
func (c *Comment) marshal(fam TableFamily, rev uint32) ([]byte, error) {
|
|
if len(*c) >= CommentSize {
|
|
return nil, fmt.Errorf("Comment must be less than %d bytes", CommentSize)
|
|
}
|
|
data := make([]byte, CommentSize)
|
|
copy(data, []byte(*c))
|
|
return data, nil
|
|
}
|
|
|
|
func (c *Comment) unmarshal(fam TableFamily, rev uint32, data []byte) error {
|
|
if len(data) != CommentSize {
|
|
return fmt.Errorf("Comment takes exactly %d bytes", CommentSize)
|
|
}
|
|
*c = Comment(bytes.TrimRight(data, "\x00"))
|
|
return nil
|
|
}
|