|
1
|
|
|
<?php |
|
2
|
|
|
|
|
3
|
|
|
namespace Kodus\Mail\SMTP; |
|
4
|
|
|
|
|
5
|
|
|
use php_user_filter as Filter; |
|
6
|
|
|
|
|
7
|
1 |
|
stream_filter_register(SMTPDotStuffingFilter::FILTER_NAME, SMTPDotStuffingFilter::class); |
|
8
|
|
|
|
|
9
|
|
|
/** |
|
10
|
|
|
* This class implements a PHP stream filter that applies "dot-stuffing" to the stream contents. |
|
11
|
|
|
* |
|
12
|
|
|
* The transmission of the body of a mail message under the SMTP protocol is initiated with a `DATA` command |
|
13
|
|
|
* after which it is transmitted verbatim line by line and is terminated with an end-of-data sequence. |
|
14
|
|
|
* |
|
15
|
|
|
* This sequence consists of a new-line (`<CR><LF>`), a single full stop (`"."`), followed by another new-line. |
|
16
|
|
|
* |
|
17
|
|
|
* Since a message body can contain a line with just a period as part of the text, the client sends two periods |
|
18
|
|
|
* every time a line starts with a period; correspondingly, the server replaces every sequence of two periods |
|
19
|
|
|
* at the beginning of a line with a single one. |
|
20
|
|
|
*/ |
|
21
|
|
|
class SMTPDotStuffingFilter extends Filter |
|
22
|
|
|
{ |
|
23
|
|
|
const FILTER_NAME = "smtp.dot_stuffing"; |
|
24
|
|
|
|
|
25
|
|
|
/** |
|
26
|
|
|
* @var string |
|
27
|
|
|
*/ |
|
28
|
|
|
private $last_two_bytes = ""; |
|
29
|
|
|
|
|
30
|
|
|
/** |
|
31
|
|
|
* @param resource $in |
|
32
|
|
|
* @param resource $out |
|
33
|
|
|
* @param int &$consumed |
|
34
|
|
|
* @param bool $closing |
|
35
|
|
|
* |
|
36
|
|
|
* @return int |
|
37
|
|
|
*/ |
|
38
|
3 |
|
public function filter($in, $out, &$consumed, $closing): int |
|
39
|
|
|
{ |
|
40
|
3 |
|
while ($bucket = stream_bucket_make_writeable($in)) { |
|
41
|
3 |
|
$data = substr( |
|
42
|
3 |
|
str_replace( |
|
43
|
3 |
|
"\r\n.", |
|
44
|
3 |
|
"\r\n..", |
|
45
|
3 |
|
$this->last_two_bytes . $bucket->data |
|
46
|
3 |
|
), |
|
47
|
3 |
|
strlen($this->last_two_bytes) |
|
48
|
3 |
|
); |
|
49
|
|
|
|
|
50
|
3 |
|
$this->last_two_bytes = substr($this->last_two_bytes . $bucket->data, -2); |
|
51
|
|
|
|
|
52
|
3 |
|
$consumed += $bucket->datalen; |
|
53
|
|
|
|
|
54
|
3 |
|
$bucket->data = $data; |
|
55
|
3 |
|
$bucket->datalen = strlen($data); |
|
56
|
|
|
|
|
57
|
3 |
|
stream_bucket_append($out, $bucket); |
|
58
|
3 |
|
} |
|
59
|
|
|
|
|
60
|
3 |
|
return PSFS_PASS_ON; |
|
61
|
|
|
} |
|
62
|
|
|
} |
|
63
|
|
|
|
kodus /
mail
