1/*
2 * Copyright (C) 2007 David Malone <dwmalone@FreeBSD.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
| 1/*
2 * Copyright (C) 2007 David Malone <dwmalone@FreeBSD.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
|
26 * $FreeBSD: head/sys/netinet/accf_dns.c 192848 2009-05-26 20:00:30Z jhb $
| 26 * $FreeBSD: head/sys/netinet/accf_dns.c 193272 2009-06-01 21:17:03Z jhb $
|
27 */
28
29#define ACCEPT_FILTER_MOD
30
31#include <sys/param.h>
32#include <sys/kernel.h>
33#include <sys/mbuf.h>
34#include <sys/module.h>
35#include <sys/signalvar.h>
36#include <sys/sysctl.h>
37#include <sys/socketvar.h>
38
39/* check for full DNS request */
| 27 */
28
29#define ACCEPT_FILTER_MOD
30
31#include <sys/param.h>
32#include <sys/kernel.h>
33#include <sys/mbuf.h>
34#include <sys/module.h>
35#include <sys/signalvar.h>
36#include <sys/sysctl.h>
37#include <sys/socketvar.h>
38
39/* check for full DNS request */
|
40static void sohasdns(struct socket *so, void *arg, int waitflag);
| 40static int sohasdns(struct socket *so, void *arg, int waitflag);
|
41
42struct packet {
43 struct mbuf *m; /* Current mbuf. */
44 struct mbuf *n; /* nextpkt mbuf. */
45 unsigned long moff; /* Offset of the beginning of m. */
46 unsigned long offset; /* Which offset we are working at. */
47 unsigned long len; /* The number of bytes we have to play with. */
48};
49
50#define DNS_OK 0
51#define DNS_WAIT -1
52#define DNS_RUN -2
53
54/* check we can skip over various parts of DNS request */
55static int skippacket(struct sockbuf *sb);
56
57static struct accept_filter accf_dns_filter = {
58 "dnsready",
59 sohasdns,
60 NULL,
61 NULL
62};
63
64static moduledata_t accf_dns_mod = {
65 "accf_dns",
66 accept_filt_generic_mod_event,
67 &accf_dns_filter
68};
69
70DECLARE_MODULE(accf_dns, accf_dns_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE);
71
| 41
42struct packet {
43 struct mbuf *m; /* Current mbuf. */
44 struct mbuf *n; /* nextpkt mbuf. */
45 unsigned long moff; /* Offset of the beginning of m. */
46 unsigned long offset; /* Which offset we are working at. */
47 unsigned long len; /* The number of bytes we have to play with. */
48};
49
50#define DNS_OK 0
51#define DNS_WAIT -1
52#define DNS_RUN -2
53
54/* check we can skip over various parts of DNS request */
55static int skippacket(struct sockbuf *sb);
56
57static struct accept_filter accf_dns_filter = {
58 "dnsready",
59 sohasdns,
60 NULL,
61 NULL
62};
63
64static moduledata_t accf_dns_mod = {
65 "accf_dns",
66 accept_filt_generic_mod_event,
67 &accf_dns_filter
68};
69
70DECLARE_MODULE(accf_dns, accf_dns_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE);
71
|
72static void
| 72static int
|
73sohasdns(struct socket *so, void *arg, int waitflag)
74{
75 struct sockbuf *sb = &so->so_rcv;
76
77 /* If the socket is full, we're ready. */
78 if (sb->sb_cc >= sb->sb_hiwat || sb->sb_mbcnt >= sb->sb_mbmax)
79 goto ready;
80
81 /* Check to see if we have a request. */
82 if (skippacket(sb) == DNS_WAIT)
| 73sohasdns(struct socket *so, void *arg, int waitflag)
74{
75 struct sockbuf *sb = &so->so_rcv;
76
77 /* If the socket is full, we're ready. */
78 if (sb->sb_cc >= sb->sb_hiwat || sb->sb_mbcnt >= sb->sb_mbmax)
79 goto ready;
80
81 /* Check to see if we have a request. */
82 if (skippacket(sb) == DNS_WAIT)
|
83 return;
| 83 return (SU_OK);
|
84
85ready:
| 84
85ready:
|
86 so->so_upcall = NULL;
87 so->so_rcv.sb_flags &= ~SB_UPCALL;
88 soisconnected(so);
89 return;
| 86 return (SU_ISCONNECTED);
|
90}
91
92#define GET8(p, val) do { \
93 if (p->offset < p->moff) \
94 return DNS_RUN; \
95 while (p->offset >= p->moff + p->m->m_len) { \
96 p->moff += p->m->m_len; \
97 p->m = p->m->m_next; \
98 if (p->m == NULL) { \
99 p->m = p->n; \
100 p->n = p->m->m_nextpkt; \
101 } \
102 if (p->m == NULL) \
103 return DNS_WAIT; \
104 } \
105 val = *(mtod(p->m, unsigned char *) + (p->offset - p->moff)); \
106 p->offset++; \
107 } while (0)
108
109#define GET16(p, val) do { \
110 unsigned int v0, v1; \
111 GET8(p, v0); \
112 GET8(p, v1); \
113 val = v0 * 0x100 + v1; \
114 } while (0)
115
116static int
117skippacket(struct sockbuf *sb) {
118 unsigned long packlen;
119 struct packet q, *p = &q;
120
121 if (sb->sb_cc < 2)
122 return DNS_WAIT;
123
124 q.m = sb->sb_mb;
125 q.n = q.m->m_nextpkt;
126 q.moff = 0;
127 q.offset = 0;
128 q.len = sb->sb_cc;
129
130 GET16(p, packlen);
131 if (packlen + 2 > q.len)
132 return DNS_WAIT;
133
134 return DNS_OK;
135}
| 87}
88
89#define GET8(p, val) do { \
90 if (p->offset < p->moff) \
91 return DNS_RUN; \
92 while (p->offset >= p->moff + p->m->m_len) { \
93 p->moff += p->m->m_len; \
94 p->m = p->m->m_next; \
95 if (p->m == NULL) { \
96 p->m = p->n; \
97 p->n = p->m->m_nextpkt; \
98 } \
99 if (p->m == NULL) \
100 return DNS_WAIT; \
101 } \
102 val = *(mtod(p->m, unsigned char *) + (p->offset - p->moff)); \
103 p->offset++; \
104 } while (0)
105
106#define GET16(p, val) do { \
107 unsigned int v0, v1; \
108 GET8(p, v0); \
109 GET8(p, v1); \
110 val = v0 * 0x100 + v1; \
111 } while (0)
112
113static int
114skippacket(struct sockbuf *sb) {
115 unsigned long packlen;
116 struct packet q, *p = &q;
117
118 if (sb->sb_cc < 2)
119 return DNS_WAIT;
120
121 q.m = sb->sb_mb;
122 q.n = q.m->m_nextpkt;
123 q.moff = 0;
124 q.offset = 0;
125 q.len = sb->sb_cc;
126
127 GET16(p, packlen);
128 if (packlen + 2 > q.len)
129 return DNS_WAIT;
130
131 return DNS_OK;
132}
|