[src/netbsd-8]: src/sys/netinet Back out the following from ticket #1045 by m...

[martin <martin%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/52ab9670a4a3
branches:  netbsd-8
changeset: 435295:52ab9670a4a3
user:      martin <martin%NetBSD.org@localhost>
date:      Tue Oct 09 09:44:31 2018 +0000

description:
Back out the following from ticket #1045 by maxv:

        sys/netinet/ip_reass.c          1.19

Faster IPv4 packet reassembly - causes fallout, needs further investigation
(see PR kern/53664)

diffstat:

 sys/netinet/ip_reass.c |  63 ++++++++++++++++++++++++++++++++-----------------
 1 files changed, 41 insertions(+), 22 deletions(-)

diffs (156 lines):

diff -r 0bcb2efe1d50 -r 52ab9670a4a3 sys/netinet/ip_reass.c
--- a/sys/netinet/ip_reass.c    Mon Oct 08 19:09:18 2018 +0000
+++ b/sys/netinet/ip_reass.c    Tue Oct 09 09:44:31 2018 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: ip_reass.c,v 1.11.8.5 2018/10/03 17:53:56 martin Exp $ */
+/*     $NetBSD: ip_reass.c,v 1.11.8.6 2018/10/09 09:44:31 martin Exp $ */
 
 /*
  * Copyright (c) 1982, 1986, 1988, 1993
@@ -46,7 +46,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: ip_reass.c,v 1.11.8.5 2018/10/03 17:53:56 martin Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ip_reass.c,v 1.11.8.6 2018/10/09 09:44:31 martin Exp $");
 
 #include <sys/param.h>
 #include <sys/types.h>
@@ -80,8 +80,6 @@
        struct ip *             ipqe_ip;
        struct mbuf *           ipqe_m;
        bool                    ipqe_mff;
-       uint16_t                ipqe_off;
-       uint16_t                ipqe_len;
 } ipfr_qent_t;
 
 TAILQ_HEAD(ipfr_qent_head, ipfr_qent);
@@ -217,7 +215,7 @@
 struct mbuf *
 ip_reass(ipfr_qent_t *ipqe, ipfr_queue_t *fp, const u_int hash)
 {
-       struct ip *ip = ipqe->ipqe_ip;
+       struct ip *ip = ipqe->ipqe_ip, *qip;
        const int hlen = ip->ip_hl << 2;
        struct mbuf *m = ipqe->ipqe_m, *t;
        int ipsecflags = m->m_flags & (M_DECRYPTED|M_AUTHIPHDR);
@@ -232,6 +230,16 @@
        m->m_data += hlen;
        m->m_len -= hlen;
 
+#ifdef notyet
+       /* Make sure fragment limit is up-to-date. */
+       CHECK_NMBCLUSTER_PARAMS();
+
+       /* If we have too many fragments, drop the older half. */
+       if (ip_nfrags >= ip_maxfrags) {
+               ip_reass_drophalf(void);
+       }
+#endif
+
        /*
         * We are about to add a fragment; increment frag count.
         */
@@ -247,9 +255,9 @@
                 * never accept fragments  b) if maxfrag is -1, accept
                 * all fragments without limitation.
                 */
-               if (ip_maxfragpackets < 0) {
-                       /* no limit */
-               } else if (ip_nfragpackets >= ip_maxfragpackets) {
+               if (ip_maxfragpackets < 0)
+                       ;
+               else if (ip_nfragpackets >= ip_maxfragpackets) {
                        goto dropfrag;
                }
                fp = malloc(sizeof(ipfr_queue_t), M_FTABLE, M_NOWAIT);
@@ -277,7 +285,7 @@
         * Find a segment which begins after this one does.
         */
        TAILQ_FOREACH(q, &fp->ipq_fragq, ipqe_q) {
-               if (q->ipqe_off > ipqe->ipqe_off)
+               if (ntohs(q->ipqe_ip->ip_off) > ntohs(ip->ip_off))
                        break;
        }
        if (q != NULL) {
@@ -292,14 +300,15 @@
         * If it provides all of our data, drop us.
         */
        if (p != NULL) {
-               i = p->ipqe_off + p->ipqe_len - ipqe->ipqe_off;
+               i = ntohs(p->ipqe_ip->ip_off) + ntohs(p->ipqe_ip->ip_len) -
+                   ntohs(ip->ip_off);
                if (i > 0) {
-                       if (i >= ipqe->ipqe_len) {
+                       if (i >= ntohs(ip->ip_len)) {
                                goto dropfrag;
                        }
                        m_adj(ipqe->ipqe_m, i);
-                       ipqe->ipqe_off = ipqe->ipqe_off + i;
-                       ipqe->ipqe_len = ipqe->ipqe_len - i;
+                       ip->ip_off = htons(ntohs(ip->ip_off) + i);
+                       ip->ip_len = htons(ntohs(ip->ip_len) - i);
                }
        }
 
@@ -308,13 +317,17 @@
         * completely covered, dequeue them.
         */
        while (q != NULL) {
-               i = ipqe->ipqe_off + ipqe->ipqe_len - q->ipqe_off;
-               if (i <= 0) {
+               size_t end;
+
+               qip = q->ipqe_ip;
+               end = ntohs(ip->ip_off) + ntohs(ip->ip_len);
+               if (end <= ntohs(qip->ip_off)) {
                        break;
                }
-               if (i < q->ipqe_len) {
-                       q->ipqe_off = q->ipqe_off + i;
-                       q->ipqe_len = q->ipqe_len - i;
+               i = end - ntohs(qip->ip_off);
+               if (i < ntohs(qip->ip_len)) {
+                       qip->ip_len = htons(ntohs(qip->ip_len) - i);
+                       qip->ip_off = htons(ntohs(qip->ip_off) + i);
                        m_adj(q->ipqe_m, i);
                        break;
                }
@@ -338,11 +351,12 @@
        }
        next = 0;
        TAILQ_FOREACH(q, &fp->ipq_fragq, ipqe_q) {
-               if (q->ipqe_off != next) {
+               qip = q->ipqe_ip;
+               if (ntohs(qip->ip_off) != next) {
                        mutex_exit(&ipfr_lock);
                        return NULL;
                }
-               next += q->ipqe_len;
+               next += ntohs(qip->ip_len);
        }
        p = TAILQ_LAST(&fp->ipq_fragq, ipfr_qent_head);
        if (p->ipqe_mff) {
@@ -637,6 +651,13 @@
                return EINVAL;
        }
 
+       /*
+        * Adjust total IP length to not reflect header and convert
+        * offset of this to bytes.  XXX: clobbers struct ip.
+        */
+       ip->ip_len = htons(flen);
+       ip->ip_off = htons(off);
+
        /* Look for queue of fragments of this datagram. */
        mutex_enter(&ipfr_lock);
        hash = IPREASS_HASH(ip->ip_src.s_addr, ip->ip_id);
@@ -681,8 +702,6 @@
        ipqe->ipqe_mff = mff;
        ipqe->ipqe_m = m;
        ipqe->ipqe_ip = ip;
-       ipqe->ipqe_off = off;
-       ipqe->ipqe_len = flen;
 
        *m0 = ip_reass(ipqe, fp, hash);
        if (*m0) {