2 * SPDX-License-Identifier: BSD-2-Clause
4 * Copyright (c) 2000 Paycounter, Inc.
5 * Author: Alfred Perlstein <alfred@paycounter.com>, <alfred@FreeBSD.org>
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 #include <sys/cdefs.h>
31 #define ACCEPT_FILTER_MOD
33 #include <sys/param.h>
34 #include <sys/kernel.h>
36 #include <sys/module.h>
37 #include <sys/signalvar.h>
38 #include <sys/sysctl.h>
39 #include <sys/socketvar.h>
41 /* check for GET/HEAD */
42 static int sohashttpget(struct socket *so, void *arg, int waitflag);
43 /* check for HTTP/1.0 or HTTP/1.1 */
44 static int soparsehttpvers(struct socket *so, void *arg, int waitflag);
45 /* check for end of HTTP/1.x request */
46 static int soishttpconnected(struct socket *so, void *arg, int waitflag);
47 /* strcmp on an mbuf chain */
48 static int mbufstrcmp(struct mbuf *m, struct mbuf *npkt, int offset, char *cmp);
49 /* strncmp on an mbuf chain */
50 static int mbufstrncmp(struct mbuf *m, struct mbuf *npkt, int offset,
52 /* socketbuffer is full */
53 static int sbfull(struct sockbuf *sb);
55 ACCEPT_FILTER_DEFINE(accf_http, "httpready", sohashttpget, NULL, NULL, 1);
57 static int parse_http_version = 1;
59 static SYSCTL_NODE(_net_inet_accf, OID_AUTO, http,
60 CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
61 "HTTP accept filter");
62 SYSCTL_INT(_net_inet_accf_http, OID_AUTO, parsehttpversion, CTLFLAG_RW,
63 &parse_http_version, 1,
64 "Parse http version so that non 1.x requests work");
66 #ifdef ACCF_HTTP_DEBUG
67 #define DPRINT(fmt, args...) \
69 printf("%s:%d: " fmt "\n", __func__, __LINE__, ##args); \
72 #define DPRINT(fmt, args...)
76 sbfull(struct sockbuf *sb)
79 DPRINT("sbfull, cc(%ld) >= hiwat(%ld): %d, "
80 "mbcnt(%ld) >= mbmax(%ld): %d",
81 sb->sb_cc, sb->sb_hiwat, sb->sb_cc >= sb->sb_hiwat,
82 sb->sb_mbcnt, sb->sb_mbmax, sb->sb_mbcnt >= sb->sb_mbmax);
83 return (sbused(sb) >= sb->sb_hiwat || sb->sb_mbcnt >= sb->sb_mbmax);
87 * start at mbuf m, (must provide npkt if exists)
88 * starting at offset in m compare characters in mbuf chain for 'cmp'
91 mbufstrcmp(struct mbuf *m, struct mbuf *npkt, int offset, char *cmp)
95 for (; m != NULL; m = n) {
98 npkt = npkt->m_nextpkt;
99 for (; m; m = m->m_next) {
100 for (; offset < m->m_len; offset++, cmp++) {
103 else if (*cmp != *(mtod(m, char *) + offset))
115 * start at mbuf m, (must provide npkt if exists)
116 * starting at offset in m compare characters in mbuf chain for 'cmp'
117 * stop at 'max' characters
120 mbufstrncmp(struct mbuf *m, struct mbuf *npkt, int offset, int max, char *cmp)
124 for (; m != NULL; m = n) {
127 npkt = npkt->m_nextpkt;
128 for (; m; m = m->m_next) {
129 for (; offset < m->m_len; offset++, cmp++, max--) {
130 if (max == 0 || *cmp == '\0')
132 else if (*cmp != *(mtod(m, char *) + offset))
135 if (max == 0 || *cmp == '\0')
143 #define STRSETUP(sptr, slen, str) \
146 slen = sizeof(str) - 1; \
150 sohashttpget(struct socket *so, void *arg, int waitflag)
153 if ((so->so_rcv.sb_state & SBS_CANTRCVMORE) == 0 &&
154 !sbfull(&so->so_rcv)) {
159 m = so->so_rcv.sb_mb;
160 cc = sbavail(&so->so_rcv) - 1;
163 switch (*mtod(m, char *)) {
165 STRSETUP(cmp, cmplen, "ET ");
168 STRSETUP(cmp, cmplen, "EAD ");
174 if (mbufstrncmp(m, m->m_nextpkt, 1, cc, cmp) == 1) {
175 DPRINT("short cc (%d) but mbufstrncmp ok", cc);
178 DPRINT("short cc (%d) mbufstrncmp failed", cc);
182 if (mbufstrcmp(m, m->m_nextpkt, 1, cmp) == 1) {
183 DPRINT("mbufstrcmp ok");
184 if (parse_http_version == 0)
185 return (soishttpconnected(so, arg, waitflag));
187 return (soparsehttpvers(so, arg, waitflag));
189 DPRINT("mbufstrcmp bad");
194 return (SU_ISCONNECTED);
198 soparsehttpvers(struct socket *so, void *arg, int waitflag)
201 int i, cc, spaces, inspaces;
203 if ((so->so_rcv.sb_state & SBS_CANTRCVMORE) != 0 || sbfull(&so->so_rcv))
206 m = so->so_rcv.sb_mb;
207 cc = sbavail(&so->so_rcv);
208 inspaces = spaces = 0;
209 for (m = so->so_rcv.sb_mb; m; m = n) {
211 for (; m; m = m->m_next) {
212 for (i = 0; i < m->m_len; i++, cc--) {
213 switch (*(mtod(m, char *) + i)) {
232 * if we don't have enough characters
233 * left (cc < sizeof("HTTP/1.0") - 1)
234 * then see if the remaining ones
235 * are a request we can parse.
237 if (cc < sizeof("HTTP/1.0") - 1) {
238 if (mbufstrncmp(m, n, i, cc,
247 mbufstrcmp(m, n, i, "HTTP/1.0") ||
248 mbufstrcmp(m, n, i, "HTTP/1.1")) {
250 return (soishttpconnected(so,
263 * if we hit here we haven't hit something
264 * we don't understand or a newline, so try again
266 soupcall_set(so, SO_RCV, soparsehttpvers, arg);
271 return (SU_ISCONNECTED);
277 soishttpconnected(struct socket *so, void *arg, int waitflag)
284 if ((so->so_rcv.sb_state & SBS_CANTRCVMORE) != 0 || sbfull(&so->so_rcv))
288 * Walk the socketbuffer and copy the last NCHRS (3) into a, b, and c
289 * copied - how much we've copied so far
290 * ccleft - how many bytes remaining in the socketbuffer
291 * just loop over the mbufs subtracting from 'ccleft' until we only
295 ccleft = sbavail(&so->so_rcv);
299 for (m = so->so_rcv.sb_mb; m; m = n) {
301 for (; m; m = m->m_next) {
303 if (ccleft <= NCHRS) {
307 tocopy = (NCHRS - ccleft) - copied;
308 src = mtod(m, char *) + (m->m_len - tocopy);
326 if (c == '\n' && (b == '\n' || (b == '\r' && a == '\n'))) {
327 /* we have all request headers */
332 soupcall_set(so, SO_RCV, soishttpconnected, arg);
336 return (SU_ISCONNECTED);