Resource exhaustion in IP fragment reassembly.
Corresponding upstream changeset from https://www.freebsd.org/security/advisories/FreeBSD-SA-18:10.ip.asc.dev
fengbojiang(姜凤波)
parent
a98418af32
commit
2d72fc9054
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@ -42,6 +42,7 @@ __FBSDID("$FreeBSD$");
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#include <sys/hash.h>
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#include <sys/mbuf.h>
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#include <sys/malloc.h>
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#include <sys/limits.h>
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#include <sys/lock.h>
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#include <sys/mutex.h>
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#include <sys/sysctl.h>
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@ -63,13 +64,14 @@ SYSCTL_DECL(_net_inet_ip);
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/*
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* Reassembly headers are stored in hash buckets.
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*/
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#define IPREASS_NHASH_LOG2 6
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#define IPREASS_NHASH_LOG2 10
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#define IPREASS_NHASH (1 << IPREASS_NHASH_LOG2)
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#define IPREASS_HMASK (IPREASS_NHASH - 1)
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struct ipqbucket {
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TAILQ_HEAD(ipqhead, ipq) head;
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struct mtx lock;
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int count;
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};
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static VNET_DEFINE(struct ipqbucket, ipq[IPREASS_NHASH]);
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@ -82,6 +84,9 @@ static VNET_DEFINE(uint32_t, ipq_hashseed);
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#define IPQ_UNLOCK(i) mtx_unlock(&V_ipq[i].lock)
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#define IPQ_LOCK_ASSERT(i) mtx_assert(&V_ipq[i].lock, MA_OWNED)
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static VNET_DEFINE(int, ipreass_maxbucketsize);
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#define V_ipreass_maxbucketsize VNET(ipreass_maxbucketsize)
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void ipreass_init(void);
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void ipreass_drain(void);
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void ipreass_slowtimo(void);
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@ -89,27 +94,53 @@ void ipreass_slowtimo(void);
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void ipreass_destroy(void);
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#endif
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static int sysctl_maxfragpackets(SYSCTL_HANDLER_ARGS);
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static int sysctl_maxfragbucketsize(SYSCTL_HANDLER_ARGS);
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static void ipreass_zone_change(void *);
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static void ipreass_drain_tomax(void);
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static void ipq_free(struct ipqhead *, struct ipq *);
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static void ipq_free(struct ipqbucket *, struct ipq *);
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static struct ipq * ipq_reuse(int);
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static inline void
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ipq_timeout(struct ipqhead *head, struct ipq *fp)
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ipq_timeout(struct ipqbucket *bucket, struct ipq *fp)
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{
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IPSTAT_ADD(ips_fragtimeout, fp->ipq_nfrags);
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ipq_free(head, fp);
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ipq_free(bucket, fp);
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}
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static inline void
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ipq_drop(struct ipqhead *head, struct ipq *fp)
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ipq_drop(struct ipqbucket *bucket, struct ipq *fp)
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{
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IPSTAT_ADD(ips_fragdropped, fp->ipq_nfrags);
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ipq_free(head, fp);
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ipq_free(bucket, fp);
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}
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/*
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* By default, limit the number of IP fragments across all reassembly
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* queues to 1/32 of the total number of mbuf clusters.
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*
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* Limit the total number of reassembly queues per VNET to the
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* IP fragment limit, but ensure the limit will not allow any bucket
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* to grow above 100 items. (The bucket limit is
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* IP_MAXFRAGPACKETS / (IPREASS_NHASH / 2), so the 50 is the correct
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* multiplier to reach a 100-item limit.)
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* The 100-item limit was chosen as brief testing seems to show that
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* this produces "reasonable" performance on some subset of systems
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* under DoS attack.
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*/
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#define IP_MAXFRAGS (nmbclusters / 32)
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#define IP_MAXFRAGPACKETS (imin(IP_MAXFRAGS, IPREASS_NHASH * 50))
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static int maxfrags;
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static volatile u_int nfrags;
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SYSCTL_INT(_net_inet_ip, OID_AUTO, maxfrags, CTLFLAG_RW,
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&maxfrags, 0,
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"Maximum number of IPv4 fragments allowed across all reassembly queues");
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SYSCTL_UINT(_net_inet_ip, OID_AUTO, curfrags, CTLFLAG_RD,
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__DEVOLATILE(u_int *, &nfrags), 0,
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"Current number of IPv4 fragments across all reassembly queues");
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static VNET_DEFINE(uma_zone_t, ipq_zone);
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#define V_ipq_zone VNET(ipq_zone)
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SYSCTL_PROC(_net_inet_ip, OID_AUTO, maxfragpackets, CTLFLAG_VNET |
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@ -127,6 +158,10 @@ static VNET_DEFINE(int, maxfragsperpacket);
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SYSCTL_INT(_net_inet_ip, OID_AUTO, maxfragsperpacket, CTLFLAG_VNET | CTLFLAG_RW,
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&VNET_NAME(maxfragsperpacket), 0,
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"Maximum number of IPv4 fragments allowed per packet");
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SYSCTL_PROC(_net_inet_ip, OID_AUTO, maxfragbucketsize,
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CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_MPSAFE | CTLFLAG_RW, NULL, 0,
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sysctl_maxfragbucketsize, "I",
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"Maximum number of IPv4 fragment reassembly queue entries per bucket");
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/*
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* Take incoming datagram fragment and try to reassemble it into
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@ -146,9 +181,9 @@ ip_reass(struct mbuf *m)
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struct mbuf *p, *q, *nq, *t;
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struct ipq *fp;
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struct ipqhead *head;
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int i, hlen, next;
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int i, hlen, next, tmpmax;
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u_int8_t ecn, ecn0;
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uint32_t hash;
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uint32_t hash, hashkey[3];
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#ifdef RSS
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uint32_t rss_hash, rss_type;
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#endif
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@ -156,8 +191,12 @@ ip_reass(struct mbuf *m)
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/*
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* If no reassembling or maxfragsperpacket are 0,
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* never accept fragments.
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* Also, drop packet if it would exceed the maximum
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* number of fragments.
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*/
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if (V_noreass == 1 || V_maxfragsperpacket == 0) {
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tmpmax = maxfrags;
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if (V_noreass == 1 || V_maxfragsperpacket == 0 ||
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(tmpmax >= 0 && nfrags >= (u_int)tmpmax)) {
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IPSTAT_INC(ips_fragments);
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IPSTAT_INC(ips_fragdropped);
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m_freem(m);
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@ -202,8 +241,12 @@ ip_reass(struct mbuf *m)
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m->m_data += hlen;
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m->m_len -= hlen;
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hash = ip->ip_src.s_addr ^ ip->ip_id;
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hash = jenkins_hash32(&hash, 1, V_ipq_hashseed) & IPREASS_HMASK;
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hashkey[0] = ip->ip_src.s_addr;
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hashkey[1] = ip->ip_dst.s_addr;
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hashkey[2] = (uint32_t)ip->ip_p << 16;
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hashkey[2] += ip->ip_id;
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hash = jenkins_hash32(hashkey, nitems(hashkey), V_ipq_hashseed);
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hash &= IPREASS_HMASK;
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head = &V_ipq[hash].head;
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IPQ_LOCK(hash);
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@ -224,9 +267,12 @@ ip_reass(struct mbuf *m)
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* If first fragment to arrive, create a reassembly queue.
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*/
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if (fp == NULL) {
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fp = uma_zalloc(V_ipq_zone, M_NOWAIT);
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if (V_ipq[hash].count < V_ipreass_maxbucketsize)
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fp = uma_zalloc(V_ipq_zone, M_NOWAIT);
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if (fp == NULL)
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fp = ipq_reuse(hash);
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if (fp == NULL)
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goto dropfrag;
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#ifdef MAC
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if (mac_ipq_init(fp, M_NOWAIT) != 0) {
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uma_zfree(V_ipq_zone, fp);
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@ -236,7 +282,9 @@ ip_reass(struct mbuf *m)
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mac_ipq_create(m, fp);
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#endif
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TAILQ_INSERT_HEAD(head, fp, ipq_list);
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V_ipq[hash].count++;
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fp->ipq_nfrags = 1;
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atomic_add_int(&nfrags, 1);
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fp->ipq_ttl = IPFRAGTTL;
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fp->ipq_p = ip->ip_p;
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fp->ipq_id = ip->ip_id;
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@ -247,6 +295,7 @@ ip_reass(struct mbuf *m)
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goto done;
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} else {
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fp->ipq_nfrags++;
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atomic_add_int(&nfrags, 1);
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#ifdef MAC
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mac_ipq_update(m, fp);
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#endif
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@ -323,6 +372,7 @@ ip_reass(struct mbuf *m)
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m->m_nextpkt = nq;
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IPSTAT_INC(ips_fragdropped);
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fp->ipq_nfrags--;
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atomic_subtract_int(&nfrags, 1);
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m_freem(q);
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}
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@ -340,7 +390,7 @@ ip_reass(struct mbuf *m)
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for (p = NULL, q = fp->ipq_frags; q; p = q, q = q->m_nextpkt) {
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if (ntohs(GETIP(q)->ip_off) != next) {
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if (fp->ipq_nfrags > V_maxfragsperpacket)
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ipq_drop(head, fp);
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ipq_drop(&V_ipq[hash], fp);
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goto done;
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}
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next += ntohs(GETIP(q)->ip_len);
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@ -348,7 +398,7 @@ ip_reass(struct mbuf *m)
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/* Make sure the last packet didn't have the IP_MF flag */
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if (p->m_flags & M_IP_FRAG) {
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if (fp->ipq_nfrags > V_maxfragsperpacket)
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ipq_drop(head, fp);
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ipq_drop(&V_ipq[hash], fp);
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goto done;
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}
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@ -359,7 +409,7 @@ ip_reass(struct mbuf *m)
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ip = GETIP(q);
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if (next + (ip->ip_hl << 2) > IP_MAXPACKET) {
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IPSTAT_INC(ips_toolong);
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ipq_drop(head, fp);
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ipq_drop(&V_ipq[hash], fp);
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goto done;
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}
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@ -387,6 +437,7 @@ ip_reass(struct mbuf *m)
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while (m->m_pkthdr.csum_data & 0xffff0000)
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m->m_pkthdr.csum_data = (m->m_pkthdr.csum_data & 0xffff) +
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(m->m_pkthdr.csum_data >> 16);
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atomic_subtract_int(&nfrags, fp->ipq_nfrags);
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#ifdef MAC
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mac_ipq_reassemble(fp, m);
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mac_ipq_destroy(fp);
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@ -401,6 +452,7 @@ ip_reass(struct mbuf *m)
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ip->ip_src = fp->ipq_src;
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ip->ip_dst = fp->ipq_dst;
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TAILQ_REMOVE(head, fp, ipq_list);
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V_ipq[hash].count--;
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uma_zfree(V_ipq_zone, fp);
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m->m_len += (ip->ip_hl << 2);
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m->m_data -= (ip->ip_hl << 2);
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@ -446,8 +498,10 @@ ip_reass(struct mbuf *m)
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dropfrag:
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IPSTAT_INC(ips_fragdropped);
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if (fp != NULL)
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if (fp != NULL) {
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fp->ipq_nfrags--;
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atomic_subtract_int(&nfrags, 1);
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}
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m_freem(m);
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done:
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IPQ_UNLOCK(hash);
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@ -462,21 +516,27 @@ done:
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void
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ipreass_init(void)
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{
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int max;
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for (int i = 0; i < IPREASS_NHASH; i++) {
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TAILQ_INIT(&V_ipq[i].head);
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mtx_init(&V_ipq[i].lock, "IP reassembly", NULL,
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MTX_DEF | MTX_DUPOK);
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V_ipq[i].count = 0;
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}
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V_ipq_hashseed = arc4random();
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V_maxfragsperpacket = 16;
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V_ipq_zone = uma_zcreate("ipq", sizeof(struct ipq), NULL, NULL, NULL,
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NULL, UMA_ALIGN_PTR, 0);
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uma_zone_set_max(V_ipq_zone, nmbclusters / 32);
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max = IP_MAXFRAGPACKETS;
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max = uma_zone_set_max(V_ipq_zone, max);
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V_ipreass_maxbucketsize = imax(max / (IPREASS_NHASH / 2), 1);
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if (IS_DEFAULT_VNET(curvnet))
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if (IS_DEFAULT_VNET(curvnet)) {
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maxfrags = IP_MAXFRAGS;
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EVENTHANDLER_REGISTER(nmbclusters_change, ipreass_zone_change,
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NULL, EVENTHANDLER_PRI_ANY);
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}
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}
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/*
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@ -491,7 +551,7 @@ ipreass_slowtimo(void)
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IPQ_LOCK(i);
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TAILQ_FOREACH_SAFE(fp, &V_ipq[i].head, ipq_list, tmp)
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if (--fp->ipq_ttl == 0)
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ipq_timeout(&V_ipq[i].head, fp);
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ipq_timeout(&V_ipq[i], fp);
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IPQ_UNLOCK(i);
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}
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}
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@ -506,7 +566,10 @@ ipreass_drain(void)
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for (int i = 0; i < IPREASS_NHASH; i++) {
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IPQ_LOCK(i);
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while(!TAILQ_EMPTY(&V_ipq[i].head))
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ipq_drop(&V_ipq[i].head, TAILQ_FIRST(&V_ipq[i].head));
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ipq_drop(&V_ipq[i], TAILQ_FIRST(&V_ipq[i].head));
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KASSERT(V_ipq[i].count == 0,
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("%s: V_ipq[%d] count %d (V_ipq=%p)", __func__, i,
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V_ipq[i].count, V_ipq));
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IPQ_UNLOCK(i);
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}
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}
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@ -534,8 +597,22 @@ ipreass_destroy(void)
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static void
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ipreass_drain_tomax(void)
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{
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struct ipq *fp;
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int target;
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/*
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* Make sure each bucket is under the new limit. If
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* necessary, drop enough of the oldest elements from
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* each bucket to get under the new limit.
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*/
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for (int i = 0; i < IPREASS_NHASH; i++) {
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IPQ_LOCK(i);
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while (V_ipq[i].count > V_ipreass_maxbucketsize &&
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(fp = TAILQ_LAST(&V_ipq[i].head, ipqhead)) != NULL)
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ipq_timeout(&V_ipq[i], fp);
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IPQ_UNLOCK(i);
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}
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/*
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* If we are over the maximum number of fragments,
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* drain off enough to get down to the new limit,
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@ -544,13 +621,11 @@ ipreass_drain_tomax(void)
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*/
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target = uma_zone_get_max(V_ipq_zone);
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while (uma_zone_get_cur(V_ipq_zone) > target) {
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struct ipq *fp;
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for (int i = 0; i < IPREASS_NHASH; i++) {
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IPQ_LOCK(i);
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fp = TAILQ_LAST(&V_ipq[i].head, ipqhead);
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if (fp != NULL)
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ipq_timeout(&V_ipq[i].head, fp);
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ipq_timeout(&V_ipq[i], fp);
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IPQ_UNLOCK(i);
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}
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}
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@ -559,9 +634,20 @@ ipreass_drain_tomax(void)
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static void
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ipreass_zone_change(void *tag)
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{
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VNET_ITERATOR_DECL(vnet_iter);
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int max;
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uma_zone_set_max(V_ipq_zone, nmbclusters / 32);
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ipreass_drain_tomax();
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maxfrags = IP_MAXFRAGS;
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max = IP_MAXFRAGPACKETS;
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VNET_LIST_RLOCK_NOSLEEP();
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VNET_FOREACH(vnet_iter) {
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CURVNET_SET(vnet_iter);
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max = uma_zone_set_max(V_ipq_zone, max);
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V_ipreass_maxbucketsize = imax(max / (IPREASS_NHASH / 2), 1);
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ipreass_drain_tomax();
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CURVNET_RESTORE();
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}
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VNET_LIST_RUNLOCK_NOSLEEP();
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}
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/*
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@ -589,6 +675,7 @@ sysctl_maxfragpackets(SYSCTL_HANDLER_ARGS)
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* and place an extreme upper bound.
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*/
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max = uma_zone_set_max(V_ipq_zone, max);
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V_ipreass_maxbucketsize = imax(max / (IPREASS_NHASH / 2), 1);
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ipreass_drain_tomax();
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V_noreass = 0;
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} else if (max == 0) {
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@ -597,6 +684,7 @@ sysctl_maxfragpackets(SYSCTL_HANDLER_ARGS)
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} else if (max == -1) {
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V_noreass = 0;
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uma_zone_set_max(V_ipq_zone, 0);
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V_ipreass_maxbucketsize = INT_MAX;
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} else
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return (EINVAL);
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return (0);
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@ -610,49 +698,72 @@ static struct ipq *
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ipq_reuse(int start)
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{
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struct ipq *fp;
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int i;
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int bucket, i;
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IPQ_LOCK_ASSERT(start);
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for (i = start;; i++) {
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if (i == IPREASS_NHASH)
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i = 0;
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if (i != start && IPQ_TRYLOCK(i) == 0)
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for (i = 0; i < IPREASS_NHASH; i++) {
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bucket = (start + i) % IPREASS_NHASH;
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if (bucket != start && IPQ_TRYLOCK(bucket) == 0)
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continue;
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fp = TAILQ_LAST(&V_ipq[i].head, ipqhead);
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fp = TAILQ_LAST(&V_ipq[bucket].head, ipqhead);
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if (fp) {
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struct mbuf *m;
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IPSTAT_ADD(ips_fragtimeout, fp->ipq_nfrags);
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atomic_subtract_int(&nfrags, fp->ipq_nfrags);
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while (fp->ipq_frags) {
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m = fp->ipq_frags;
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fp->ipq_frags = m->m_nextpkt;
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||||
m_freem(m);
|
||||
}
|
||||
TAILQ_REMOVE(&V_ipq[i].head, fp, ipq_list);
|
||||
if (i != start)
|
||||
IPQ_UNLOCK(i);
|
||||
IPQ_LOCK_ASSERT(start);
|
||||
return (fp);
|
||||
TAILQ_REMOVE(&V_ipq[bucket].head, fp, ipq_list);
|
||||
V_ipq[bucket].count--;
|
||||
if (bucket != start)
|
||||
IPQ_UNLOCK(bucket);
|
||||
break;
|
||||
}
|
||||
if (i != start)
|
||||
IPQ_UNLOCK(i);
|
||||
if (bucket != start)
|
||||
IPQ_UNLOCK(bucket);
|
||||
}
|
||||
IPQ_LOCK_ASSERT(start);
|
||||
return (fp);
|
||||
}
|
||||
|
||||
/*
|
||||
* Free a fragment reassembly header and all associated datagrams.
|
||||
*/
|
||||
static void
|
||||
ipq_free(struct ipqhead *fhp, struct ipq *fp)
|
||||
ipq_free(struct ipqbucket *bucket, struct ipq *fp)
|
||||
{
|
||||
struct mbuf *q;
|
||||
|
||||
atomic_subtract_int(&nfrags, fp->ipq_nfrags);
|
||||
while (fp->ipq_frags) {
|
||||
q = fp->ipq_frags;
|
||||
fp->ipq_frags = q->m_nextpkt;
|
||||
m_freem(q);
|
||||
}
|
||||
TAILQ_REMOVE(fhp, fp, ipq_list);
|
||||
TAILQ_REMOVE(&bucket->head, fp, ipq_list);
|
||||
bucket->count--;
|
||||
uma_zfree(V_ipq_zone, fp);
|
||||
}
|
||||
|
||||
/*
|
||||
* Get or set the maximum number of reassembly queues per bucket.
|
||||
*/
|
||||
static int
|
||||
sysctl_maxfragbucketsize(SYSCTL_HANDLER_ARGS)
|
||||
{
|
||||
int error, max;
|
||||
|
||||
max = V_ipreass_maxbucketsize;
|
||||
error = sysctl_handle_int(oidp, &max, 0, req);
|
||||
if (error || !req->newptr)
|
||||
return (error);
|
||||
if (max <= 0)
|
||||
return (EINVAL);
|
||||
V_ipreass_maxbucketsize = max;
|
||||
ipreass_drain_tomax();
|
||||
return (0);
|
||||
}
|
||||
|
|
|
|||
|
|
@ -36,6 +36,7 @@ __FBSDID("$FreeBSD$");
|
|||
|
||||
#include <sys/param.h>
|
||||
#include <sys/systm.h>
|
||||
#include <sys/hash.h>
|
||||
#include <sys/malloc.h>
|
||||
#include <sys/mbuf.h>
|
||||
#include <sys/domain.h>
|
||||
|
|
@ -47,6 +48,8 @@ __FBSDID("$FreeBSD$");
|
|||
#include <sys/kernel.h>
|
||||
#include <sys/syslog.h>
|
||||
|
||||
#include <machine/atomic.h>
|
||||
|
||||
#include <net/if.h>
|
||||
#include <net/if_var.h>
|
||||
#include <net/netisr.h>
|
||||
|
|
@ -63,58 +66,112 @@ __FBSDID("$FreeBSD$");
|
|||
|
||||
#include <security/mac/mac_framework.h>
|
||||
|
||||
static void frag6_enq(struct ip6asfrag *, struct ip6asfrag *);
|
||||
static void frag6_deq(struct ip6asfrag *);
|
||||
static void frag6_insque(struct ip6q *, struct ip6q *);
|
||||
static void frag6_remque(struct ip6q *);
|
||||
static void frag6_freef(struct ip6q *);
|
||||
|
||||
static struct mtx ip6qlock;
|
||||
/*
|
||||
* These fields all protected by ip6qlock.
|
||||
* Reassembly headers are stored in hash buckets.
|
||||
*/
|
||||
static VNET_DEFINE(u_int, frag6_nfragpackets);
|
||||
static VNET_DEFINE(u_int, frag6_nfrags);
|
||||
static VNET_DEFINE(struct ip6q, ip6q); /* ip6 reassemble queue */
|
||||
#define IP6REASS_NHASH_LOG2 10
|
||||
#define IP6REASS_NHASH (1 << IP6REASS_NHASH_LOG2)
|
||||
#define IP6REASS_HMASK (IP6REASS_NHASH - 1)
|
||||
|
||||
static void frag6_enq(struct ip6asfrag *, struct ip6asfrag *,
|
||||
uint32_t bucket __unused);
|
||||
static void frag6_deq(struct ip6asfrag *, uint32_t bucket __unused);
|
||||
static void frag6_insque_head(struct ip6q *, struct ip6q *,
|
||||
uint32_t bucket);
|
||||
static void frag6_remque(struct ip6q *, uint32_t bucket);
|
||||
static void frag6_freef(struct ip6q *, uint32_t bucket);
|
||||
|
||||
struct ip6qbucket {
|
||||
struct ip6q ip6q;
|
||||
struct mtx lock;
|
||||
int count;
|
||||
};
|
||||
|
||||
static VNET_DEFINE(volatile u_int, frag6_nfragpackets);
|
||||
volatile u_int frag6_nfrags = 0;
|
||||
static VNET_DEFINE(struct ip6qbucket, ip6q[IP6REASS_NHASH]);
|
||||
static VNET_DEFINE(uint32_t, ip6q_hashseed);
|
||||
|
||||
#define V_frag6_nfragpackets VNET(frag6_nfragpackets)
|
||||
#define V_frag6_nfrags VNET(frag6_nfrags)
|
||||
#define V_ip6q VNET(ip6q)
|
||||
#define V_ip6q_hashseed VNET(ip6q_hashseed)
|
||||
|
||||
#define IP6Q_LOCK_INIT() mtx_init(&ip6qlock, "ip6qlock", NULL, MTX_DEF);
|
||||
#define IP6Q_LOCK() mtx_lock(&ip6qlock)
|
||||
#define IP6Q_TRYLOCK() mtx_trylock(&ip6qlock)
|
||||
#define IP6Q_LOCK_ASSERT() mtx_assert(&ip6qlock, MA_OWNED)
|
||||
#define IP6Q_UNLOCK() mtx_unlock(&ip6qlock)
|
||||
#define IP6Q_LOCK(i) mtx_lock(&V_ip6q[(i)].lock)
|
||||
#define IP6Q_TRYLOCK(i) mtx_trylock(&V_ip6q[(i)].lock)
|
||||
#define IP6Q_LOCK_ASSERT(i) mtx_assert(&V_ip6q[(i)].lock, MA_OWNED)
|
||||
#define IP6Q_UNLOCK(i) mtx_unlock(&V_ip6q[(i)].lock)
|
||||
#define IP6Q_HEAD(i) (&V_ip6q[(i)].ip6q)
|
||||
|
||||
static MALLOC_DEFINE(M_FTABLE, "fragment", "fragment reassembly header");
|
||||
|
||||
/*
|
||||
* By default, limit the number of IP6 fragments across all reassembly
|
||||
* queues to 1/32 of the total number of mbuf clusters.
|
||||
*
|
||||
* Limit the total number of reassembly queues per VNET to the
|
||||
* IP6 fragment limit, but ensure the limit will not allow any bucket
|
||||
* to grow above 100 items. (The bucket limit is
|
||||
* IP_MAXFRAGPACKETS / (IPREASS_NHASH / 2), so the 50 is the correct
|
||||
* multiplier to reach a 100-item limit.)
|
||||
* The 100-item limit was chosen as brief testing seems to show that
|
||||
* this produces "reasonable" performance on some subset of systems
|
||||
* under DoS attack.
|
||||
*/
|
||||
#define IP6_MAXFRAGS (nmbclusters / 32)
|
||||
#define IP6_MAXFRAGPACKETS (imin(IP6_MAXFRAGS, IP6REASS_NHASH * 50))
|
||||
|
||||
/*
|
||||
* Initialise reassembly queue and fragment identifier.
|
||||
*/
|
||||
void
|
||||
frag6_set_bucketsize()
|
||||
{
|
||||
int i;
|
||||
|
||||
if ((i = V_ip6_maxfragpackets) > 0)
|
||||
V_ip6_maxfragbucketsize = imax(i / (IP6REASS_NHASH / 2), 1);
|
||||
}
|
||||
|
||||
static void
|
||||
frag6_change(void *tag)
|
||||
{
|
||||
VNET_ITERATOR_DECL(vnet_iter);
|
||||
|
||||
V_ip6_maxfragpackets = nmbclusters / 4;
|
||||
V_ip6_maxfrags = nmbclusters / 4;
|
||||
ip6_maxfrags = IP6_MAXFRAGS;
|
||||
VNET_LIST_RLOCK_NOSLEEP();
|
||||
VNET_FOREACH(vnet_iter) {
|
||||
CURVNET_SET(vnet_iter);
|
||||
V_ip6_maxfragpackets = IP6_MAXFRAGPACKETS;
|
||||
frag6_set_bucketsize();
|
||||
CURVNET_RESTORE();
|
||||
}
|
||||
VNET_LIST_RUNLOCK_NOSLEEP();
|
||||
}
|
||||
|
||||
void
|
||||
frag6_init(void)
|
||||
{
|
||||
struct ip6q *q6;
|
||||
int i;
|
||||
|
||||
V_ip6_maxfragpackets = IP6_MAXFRAGPACKETS;
|
||||
frag6_set_bucketsize();
|
||||
for (i = 0; i < IP6REASS_NHASH; i++) {
|
||||
q6 = IP6Q_HEAD(i);
|
||||
q6->ip6q_next = q6->ip6q_prev = q6;
|
||||
mtx_init(&V_ip6q[i].lock, "ip6qlock", NULL, MTX_DEF);
|
||||
V_ip6q[i].count = 0;
|
||||
}
|
||||
V_ip6q_hashseed = arc4random();
|
||||
V_ip6_maxfragsperpacket = 64;
|
||||
|
||||
V_ip6_maxfragpackets = nmbclusters / 4;
|
||||
V_ip6_maxfrags = nmbclusters / 4;
|
||||
V_ip6q.ip6q_next = V_ip6q.ip6q_prev = &V_ip6q;
|
||||
|
||||
if (!IS_DEFAULT_VNET(curvnet))
|
||||
return;
|
||||
|
||||
ip6_maxfrags = IP6_MAXFRAGS;
|
||||
EVENTHANDLER_REGISTER(nmbclusters_change,
|
||||
frag6_change, NULL, EVENTHANDLER_PRI_ANY);
|
||||
|
||||
IP6Q_LOCK_INIT();
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
@ -155,12 +212,13 @@ frag6_input(struct mbuf **mp, int *offp, int proto)
|
|||
struct mbuf *m = *mp, *t;
|
||||
struct ip6_hdr *ip6;
|
||||
struct ip6_frag *ip6f;
|
||||
struct ip6q *q6;
|
||||
struct ip6q *head, *q6;
|
||||
struct ip6asfrag *af6, *ip6af, *af6dwn;
|
||||
struct in6_ifaddr *ia;
|
||||
int offset = *offp, nxt, i, next;
|
||||
int first_frag = 0;
|
||||
int fragoff, frgpartlen; /* must be larger than u_int16_t */
|
||||
uint32_t hash, hashkey[sizeof(struct in6_addr) * 2 + 1], *hashkeyp;
|
||||
struct ifnet *dstifp;
|
||||
u_int8_t ecn, ecn0;
|
||||
#ifdef RSS
|
||||
|
|
@ -228,19 +286,38 @@ frag6_input(struct mbuf **mp, int *offp, int proto)
|
|||
return (ip6f->ip6f_nxt);
|
||||
}
|
||||
|
||||
IP6Q_LOCK();
|
||||
/* Get fragment length and discard 0-byte fragments. */
|
||||
frgpartlen = sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen) - offset;
|
||||
if (frgpartlen == 0) {
|
||||
icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER,
|
||||
offsetof(struct ip6_hdr, ip6_plen));
|
||||
in6_ifstat_inc(dstifp, ifs6_reass_fail);
|
||||
IP6STAT_INC(ip6s_fragdropped);
|
||||
return IPPROTO_DONE;
|
||||
}
|
||||
|
||||
hashkeyp = hashkey;
|
||||
memcpy(hashkeyp, &ip6->ip6_src, sizeof(struct in6_addr));
|
||||
hashkeyp += sizeof(struct in6_addr) / sizeof(*hashkeyp);
|
||||
memcpy(hashkeyp, &ip6->ip6_dst, sizeof(struct in6_addr));
|
||||
hashkeyp += sizeof(struct in6_addr) / sizeof(*hashkeyp);
|
||||
*hashkeyp = ip6f->ip6f_ident;
|
||||
hash = jenkins_hash32(hashkey, nitems(hashkey), V_ip6q_hashseed);
|
||||
hash &= IP6REASS_HMASK;
|
||||
head = IP6Q_HEAD(hash);
|
||||
IP6Q_LOCK(hash);
|
||||
|
||||
/*
|
||||
* Enforce upper bound on number of fragments.
|
||||
* If maxfrag is 0, never accept fragments.
|
||||
* If maxfrag is -1, accept all fragments without limitation.
|
||||
*/
|
||||
if (V_ip6_maxfrags < 0)
|
||||
if (ip6_maxfrags < 0)
|
||||
;
|
||||
else if (V_frag6_nfrags >= (u_int)V_ip6_maxfrags)
|
||||
else if (frag6_nfrags >= (u_int)ip6_maxfrags)
|
||||
goto dropfrag;
|
||||
|
||||
for (q6 = V_ip6q.ip6q_next; q6 != &V_ip6q; q6 = q6->ip6q_next)
|
||||
for (q6 = head->ip6q_next; q6 != head; q6 = q6->ip6q_next)
|
||||
if (ip6f->ip6f_ident == q6->ip6q_ident &&
|
||||
IN6_ARE_ADDR_EQUAL(&ip6->ip6_src, &q6->ip6q_src) &&
|
||||
IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &q6->ip6q_dst)
|
||||
|
|
@ -250,7 +327,7 @@ frag6_input(struct mbuf **mp, int *offp, int proto)
|
|||
)
|
||||
break;
|
||||
|
||||
if (q6 == &V_ip6q) {
|
||||
if (q6 == head) {
|
||||
/*
|
||||
* the first fragment to arrive, create a reassembly queue.
|
||||
*/
|
||||
|
|
@ -265,9 +342,10 @@ frag6_input(struct mbuf **mp, int *offp, int proto)
|
|||
*/
|
||||
if (V_ip6_maxfragpackets < 0)
|
||||
;
|
||||
else if (V_frag6_nfragpackets >= (u_int)V_ip6_maxfragpackets)
|
||||
else if (V_ip6q[hash].count >= V_ip6_maxfragbucketsize ||
|
||||
V_frag6_nfragpackets >= (u_int)V_ip6_maxfragpackets)
|
||||
goto dropfrag;
|
||||
V_frag6_nfragpackets++;
|
||||
atomic_add_int(&V_frag6_nfragpackets, 1);
|
||||
q6 = (struct ip6q *)malloc(sizeof(struct ip6q), M_FTABLE,
|
||||
M_NOWAIT);
|
||||
if (q6 == NULL)
|
||||
|
|
@ -280,7 +358,7 @@ frag6_input(struct mbuf **mp, int *offp, int proto)
|
|||
}
|
||||
mac_ip6q_create(m, q6);
|
||||
#endif
|
||||
frag6_insque(q6, &V_ip6q);
|
||||
frag6_insque_head(q6, head, hash);
|
||||
|
||||
/* ip6q_nxt will be filled afterwards, from 1st fragment */
|
||||
q6->ip6q_down = q6->ip6q_up = (struct ip6asfrag *)q6;
|
||||
|
|
@ -314,21 +392,20 @@ frag6_input(struct mbuf **mp, int *offp, int proto)
|
|||
* in size.
|
||||
* If it would exceed, discard the fragment and return an ICMP error.
|
||||
*/
|
||||
frgpartlen = sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen) - offset;
|
||||
if (q6->ip6q_unfrglen >= 0) {
|
||||
/* The 1st fragment has already arrived. */
|
||||
if (q6->ip6q_unfrglen + fragoff + frgpartlen > IPV6_MAXPACKET) {
|
||||
icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER,
|
||||
offset - sizeof(struct ip6_frag) +
|
||||
offsetof(struct ip6_frag, ip6f_offlg));
|
||||
IP6Q_UNLOCK();
|
||||
IP6Q_UNLOCK(hash);
|
||||
return (IPPROTO_DONE);
|
||||
}
|
||||
} else if (fragoff + frgpartlen > IPV6_MAXPACKET) {
|
||||
icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER,
|
||||
offset - sizeof(struct ip6_frag) +
|
||||
offsetof(struct ip6_frag, ip6f_offlg));
|
||||
IP6Q_UNLOCK();
|
||||
IP6Q_UNLOCK(hash);
|
||||
return (IPPROTO_DONE);
|
||||
}
|
||||
/*
|
||||
|
|
@ -347,7 +424,7 @@ frag6_input(struct mbuf **mp, int *offp, int proto)
|
|||
int erroff = af6->ip6af_offset;
|
||||
|
||||
/* dequeue the fragment. */
|
||||
frag6_deq(af6);
|
||||
frag6_deq(af6, hash);
|
||||
free(af6, M_FTABLE);
|
||||
|
||||
/* adjust pointer. */
|
||||
|
|
@ -445,7 +522,7 @@ frag6_input(struct mbuf **mp, int *offp, int proto)
|
|||
}
|
||||
af6 = af6->ip6af_down;
|
||||
m_freem(IP6_REASS_MBUF(af6->ip6af_up));
|
||||
frag6_deq(af6->ip6af_up);
|
||||
frag6_deq(af6->ip6af_up, hash);
|
||||
}
|
||||
#else
|
||||
/*
|
||||
|
|
@ -494,29 +571,38 @@ insert:
|
|||
/*
|
||||
* Stick new segment in its place;
|
||||
* check for complete reassembly.
|
||||
* If not complete, check fragment limit.
|
||||
* Move to front of packet queue, as we are
|
||||
* the most recently active fragmented packet.
|
||||
*/
|
||||
frag6_enq(ip6af, af6->ip6af_up);
|
||||
V_frag6_nfrags++;
|
||||
frag6_enq(ip6af, af6->ip6af_up, hash);
|
||||
atomic_add_int(&frag6_nfrags, 1);
|
||||
q6->ip6q_nfrag++;
|
||||
#if 0 /* xxx */
|
||||
if (q6 != V_ip6q.ip6q_next) {
|
||||
frag6_remque(q6);
|
||||
frag6_insque(q6, &V_ip6q);
|
||||
if (q6 != head->ip6q_next) {
|
||||
frag6_remque(q6, hash);
|
||||
frag6_insque_head(q6, head, hash);
|
||||
}
|
||||
#endif
|
||||
next = 0;
|
||||
for (af6 = q6->ip6q_down; af6 != (struct ip6asfrag *)q6;
|
||||
af6 = af6->ip6af_down) {
|
||||
if (af6->ip6af_off != next) {
|
||||
IP6Q_UNLOCK();
|
||||
if (q6->ip6q_nfrag > V_ip6_maxfragsperpacket) {
|
||||
IP6STAT_INC(ip6s_fragdropped);
|
||||
frag6_freef(q6, hash);
|
||||
}
|
||||
IP6Q_UNLOCK(hash);
|
||||
return IPPROTO_DONE;
|
||||
}
|
||||
next += af6->ip6af_frglen;
|
||||
}
|
||||
if (af6->ip6af_up->ip6af_mff) {
|
||||
IP6Q_UNLOCK();
|
||||
if (q6->ip6q_nfrag > V_ip6_maxfragsperpacket) {
|
||||
IP6STAT_INC(ip6s_fragdropped);
|
||||
frag6_freef(q6, hash);
|
||||
}
|
||||
IP6Q_UNLOCK(hash);
|
||||
return IPPROTO_DONE;
|
||||
}
|
||||
|
||||
|
|
@ -526,10 +612,10 @@ insert:
|
|||
ip6af = q6->ip6q_down;
|
||||
t = m = IP6_REASS_MBUF(ip6af);
|
||||
af6 = ip6af->ip6af_down;
|
||||
frag6_deq(ip6af);
|
||||
frag6_deq(ip6af, hash);
|
||||
while (af6 != (struct ip6asfrag *)q6) {
|
||||
af6dwn = af6->ip6af_down;
|
||||
frag6_deq(af6);
|
||||
frag6_deq(af6, hash);
|
||||
while (t->m_next)
|
||||
t = t->m_next;
|
||||
m_adj(IP6_REASS_MBUF(af6), af6->ip6af_offset);
|
||||
|
|
@ -551,13 +637,13 @@ insert:
|
|||
#endif
|
||||
|
||||
if (ip6_deletefraghdr(m, offset, M_NOWAIT) != 0) {
|
||||
frag6_remque(q6);
|
||||
V_frag6_nfrags -= q6->ip6q_nfrag;
|
||||
frag6_remque(q6, hash);
|
||||
atomic_subtract_int(&frag6_nfrags, q6->ip6q_nfrag);
|
||||
#ifdef MAC
|
||||
mac_ip6q_destroy(q6);
|
||||
#endif
|
||||
free(q6, M_FTABLE);
|
||||
V_frag6_nfragpackets--;
|
||||
atomic_subtract_int(&V_frag6_nfragpackets, 1);
|
||||
|
||||
goto dropfrag;
|
||||
}
|
||||
|
|
@ -570,14 +656,14 @@ insert:
|
|||
*prvnxtp = nxt;
|
||||
}
|
||||
|
||||
frag6_remque(q6);
|
||||
V_frag6_nfrags -= q6->ip6q_nfrag;
|
||||
frag6_remque(q6, hash);
|
||||
atomic_subtract_int(&frag6_nfrags, q6->ip6q_nfrag);
|
||||
#ifdef MAC
|
||||
mac_ip6q_reassemble(q6, m);
|
||||
mac_ip6q_destroy(q6);
|
||||
#endif
|
||||
free(q6, M_FTABLE);
|
||||
V_frag6_nfragpackets--;
|
||||
atomic_subtract_int(&V_frag6_nfragpackets, 1);
|
||||
|
||||
if (m->m_flags & M_PKTHDR) { /* Isn't it always true? */
|
||||
int plen = 0;
|
||||
|
|
@ -599,7 +685,7 @@ insert:
|
|||
m_tag_prepend(m, mtag);
|
||||
#endif
|
||||
|
||||
IP6Q_UNLOCK();
|
||||
IP6Q_UNLOCK(hash);
|
||||
IP6STAT_INC(ip6s_reassembled);
|
||||
in6_ifstat_inc(dstifp, ifs6_reass_ok);
|
||||
|
||||
|
|
@ -621,7 +707,7 @@ insert:
|
|||
return nxt;
|
||||
|
||||
dropfrag:
|
||||
IP6Q_UNLOCK();
|
||||
IP6Q_UNLOCK(hash);
|
||||
in6_ifstat_inc(dstifp, ifs6_reass_fail);
|
||||
IP6STAT_INC(ip6s_fragdropped);
|
||||
m_freem(m);
|
||||
|
|
@ -632,19 +718,19 @@ insert:
|
|||
* Free a fragment reassembly header and all
|
||||
* associated datagrams.
|
||||
*/
|
||||
void
|
||||
frag6_freef(struct ip6q *q6)
|
||||
static void
|
||||
frag6_freef(struct ip6q *q6, uint32_t bucket)
|
||||
{
|
||||
struct ip6asfrag *af6, *down6;
|
||||
|
||||
IP6Q_LOCK_ASSERT();
|
||||
IP6Q_LOCK_ASSERT(bucket);
|
||||
|
||||
for (af6 = q6->ip6q_down; af6 != (struct ip6asfrag *)q6;
|
||||
af6 = down6) {
|
||||
struct mbuf *m = IP6_REASS_MBUF(af6);
|
||||
|
||||
down6 = af6->ip6af_down;
|
||||
frag6_deq(af6);
|
||||
frag6_deq(af6, bucket);
|
||||
|
||||
/*
|
||||
* Return ICMP time exceeded error for the 1st fragment.
|
||||
|
|
@ -666,24 +752,25 @@ frag6_freef(struct ip6q *q6)
|
|||
m_freem(m);
|
||||
free(af6, M_FTABLE);
|
||||
}
|
||||
frag6_remque(q6);
|
||||
V_frag6_nfrags -= q6->ip6q_nfrag;
|
||||
frag6_remque(q6, bucket);
|
||||
atomic_subtract_int(&frag6_nfrags, q6->ip6q_nfrag);
|
||||
#ifdef MAC
|
||||
mac_ip6q_destroy(q6);
|
||||
#endif
|
||||
free(q6, M_FTABLE);
|
||||
V_frag6_nfragpackets--;
|
||||
atomic_subtract_int(&V_frag6_nfragpackets, 1);
|
||||
}
|
||||
|
||||
/*
|
||||
* Put an ip fragment on a reassembly chain.
|
||||
* Like insque, but pointers in middle of structure.
|
||||
*/
|
||||
void
|
||||
frag6_enq(struct ip6asfrag *af6, struct ip6asfrag *up6)
|
||||
static void
|
||||
frag6_enq(struct ip6asfrag *af6, struct ip6asfrag *up6,
|
||||
uint32_t bucket __unused)
|
||||
{
|
||||
|
||||
IP6Q_LOCK_ASSERT();
|
||||
IP6Q_LOCK_ASSERT(bucket);
|
||||
|
||||
af6->ip6af_up = up6;
|
||||
af6->ip6af_down = up6->ip6af_down;
|
||||
|
|
@ -694,36 +781,41 @@ frag6_enq(struct ip6asfrag *af6, struct ip6asfrag *up6)
|
|||
/*
|
||||
* To frag6_enq as remque is to insque.
|
||||
*/
|
||||
void
|
||||
frag6_deq(struct ip6asfrag *af6)
|
||||
static void
|
||||
frag6_deq(struct ip6asfrag *af6, uint32_t bucket __unused)
|
||||
{
|
||||
|
||||
IP6Q_LOCK_ASSERT();
|
||||
IP6Q_LOCK_ASSERT(bucket);
|
||||
|
||||
af6->ip6af_up->ip6af_down = af6->ip6af_down;
|
||||
af6->ip6af_down->ip6af_up = af6->ip6af_up;
|
||||
}
|
||||
|
||||
void
|
||||
frag6_insque(struct ip6q *new, struct ip6q *old)
|
||||
static void
|
||||
frag6_insque_head(struct ip6q *new, struct ip6q *old, uint32_t bucket)
|
||||
{
|
||||
|
||||
IP6Q_LOCK_ASSERT();
|
||||
IP6Q_LOCK_ASSERT(bucket);
|
||||
KASSERT(IP6Q_HEAD(bucket) == old,
|
||||
("%s: attempt to insert at head of wrong bucket"
|
||||
" (bucket=%u, old=%p)", __func__, bucket, old));
|
||||
|
||||
new->ip6q_prev = old;
|
||||
new->ip6q_next = old->ip6q_next;
|
||||
old->ip6q_next->ip6q_prev= new;
|
||||
old->ip6q_next = new;
|
||||
V_ip6q[bucket].count++;
|
||||
}
|
||||
|
||||
void
|
||||
frag6_remque(struct ip6q *p6)
|
||||
static void
|
||||
frag6_remque(struct ip6q *p6, uint32_t bucket)
|
||||
{
|
||||
|
||||
IP6Q_LOCK_ASSERT();
|
||||
IP6Q_LOCK_ASSERT(bucket);
|
||||
|
||||
p6->ip6q_prev->ip6q_next = p6->ip6q_next;
|
||||
p6->ip6q_next->ip6q_prev = p6->ip6q_prev;
|
||||
V_ip6q[bucket].count--;
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
@ -735,37 +827,72 @@ void
|
|||
frag6_slowtimo(void)
|
||||
{
|
||||
VNET_ITERATOR_DECL(vnet_iter);
|
||||
struct ip6q *q6;
|
||||
struct ip6q *head, *q6;
|
||||
int i;
|
||||
|
||||
VNET_LIST_RLOCK_NOSLEEP();
|
||||
IP6Q_LOCK();
|
||||
VNET_FOREACH(vnet_iter) {
|
||||
CURVNET_SET(vnet_iter);
|
||||
q6 = V_ip6q.ip6q_next;
|
||||
if (q6)
|
||||
while (q6 != &V_ip6q) {
|
||||
for (i = 0; i < IP6REASS_NHASH; i++) {
|
||||
IP6Q_LOCK(i);
|
||||
head = IP6Q_HEAD(i);
|
||||
q6 = head->ip6q_next;
|
||||
if (q6 == NULL) {
|
||||
/*
|
||||
* XXXJTL: This should never happen. This
|
||||
* should turn into an assertion.
|
||||
*/
|
||||
IP6Q_UNLOCK(i);
|
||||
continue;
|
||||
}
|
||||
while (q6 != head) {
|
||||
--q6->ip6q_ttl;
|
||||
q6 = q6->ip6q_next;
|
||||
if (q6->ip6q_prev->ip6q_ttl == 0) {
|
||||
IP6STAT_INC(ip6s_fragtimeout);
|
||||
/* XXX in6_ifstat_inc(ifp, ifs6_reass_fail) */
|
||||
frag6_freef(q6->ip6q_prev);
|
||||
frag6_freef(q6->ip6q_prev, i);
|
||||
}
|
||||
}
|
||||
/*
|
||||
* If we are over the maximum number of fragments
|
||||
* (due to the limit being lowered), drain off
|
||||
* enough to get down to the new limit.
|
||||
* Note that we drain all reassembly queues if
|
||||
* maxfragpackets is 0 (fragmentation is disabled),
|
||||
* and don't enforce a limit when maxfragpackets
|
||||
* is negative.
|
||||
*/
|
||||
while ((V_ip6_maxfragpackets == 0 ||
|
||||
(V_ip6_maxfragpackets > 0 &&
|
||||
V_ip6q[i].count > V_ip6_maxfragbucketsize)) &&
|
||||
head->ip6q_prev != head) {
|
||||
IP6STAT_INC(ip6s_fragoverflow);
|
||||
/* XXX in6_ifstat_inc(ifp, ifs6_reass_fail) */
|
||||
frag6_freef(head->ip6q_prev, i);
|
||||
}
|
||||
IP6Q_UNLOCK(i);
|
||||
}
|
||||
|
||||
/*
|
||||
* If we are over the maximum number of fragments
|
||||
* (due to the limit being lowered), drain off
|
||||
* enough to get down to the new limit.
|
||||
* If we are still over the maximum number of fragmented
|
||||
* packets, drain off enough to get down to the new limit.
|
||||
*/
|
||||
while (V_frag6_nfragpackets > (u_int)V_ip6_maxfragpackets &&
|
||||
V_ip6q.ip6q_prev) {
|
||||
IP6STAT_INC(ip6s_fragoverflow);
|
||||
/* XXX in6_ifstat_inc(ifp, ifs6_reass_fail) */
|
||||
frag6_freef(V_ip6q.ip6q_prev);
|
||||
i = 0;
|
||||
while (V_ip6_maxfragpackets >= 0 &&
|
||||
V_frag6_nfragpackets > (u_int)V_ip6_maxfragpackets) {
|
||||
IP6Q_LOCK(i);
|
||||
head = IP6Q_HEAD(i);
|
||||
if (head->ip6q_prev != head) {
|
||||
IP6STAT_INC(ip6s_fragoverflow);
|
||||
/* XXX in6_ifstat_inc(ifp, ifs6_reass_fail) */
|
||||
frag6_freef(head->ip6q_prev, i);
|
||||
}
|
||||
IP6Q_UNLOCK(i);
|
||||
i = (i + 1) % IP6REASS_NHASH;
|
||||
}
|
||||
CURVNET_RESTORE();
|
||||
}
|
||||
IP6Q_UNLOCK();
|
||||
VNET_LIST_RUNLOCK_NOSLEEP();
|
||||
}
|
||||
|
||||
|
|
@ -776,22 +903,25 @@ void
|
|||
frag6_drain(void)
|
||||
{
|
||||
VNET_ITERATOR_DECL(vnet_iter);
|
||||
struct ip6q *head;
|
||||
int i;
|
||||
|
||||
VNET_LIST_RLOCK_NOSLEEP();
|
||||
if (IP6Q_TRYLOCK() == 0) {
|
||||
VNET_LIST_RUNLOCK_NOSLEEP();
|
||||
return;
|
||||
}
|
||||
VNET_FOREACH(vnet_iter) {
|
||||
CURVNET_SET(vnet_iter);
|
||||
while (V_ip6q.ip6q_next != &V_ip6q) {
|
||||
IP6STAT_INC(ip6s_fragdropped);
|
||||
/* XXX in6_ifstat_inc(ifp, ifs6_reass_fail) */
|
||||
frag6_freef(V_ip6q.ip6q_next);
|
||||
for (i = 0; i < IP6REASS_NHASH; i++) {
|
||||
if (IP6Q_TRYLOCK(i) == 0)
|
||||
continue;
|
||||
head = IP6Q_HEAD(i);
|
||||
while (head->ip6q_next != head) {
|
||||
IP6STAT_INC(ip6s_fragdropped);
|
||||
/* XXX in6_ifstat_inc(ifp, ifs6_reass_fail) */
|
||||
frag6_freef(head->ip6q_next, i);
|
||||
}
|
||||
IP6Q_UNLOCK(i);
|
||||
}
|
||||
CURVNET_RESTORE();
|
||||
}
|
||||
IP6Q_UNLOCK();
|
||||
VNET_LIST_RUNLOCK_NOSLEEP();
|
||||
}
|
||||
|
||||
|
|
|
|||
|
|
@ -637,7 +637,13 @@ struct ip6_mtuinfo {
|
|||
* receiving IF. */
|
||||
#define IPV6CTL_RFC6204W3 50 /* Accept defroute even when forwarding
|
||||
enabled */
|
||||
#define IPV6CTL_MAXID 51
|
||||
#define IPV6CTL_INTRQMAXLEN 51 /* max length of IPv6 netisr queue */
|
||||
#define IPV6CTL_INTRDQMAXLEN 52 /* max length of direct IPv6 netisr
|
||||
* queue */
|
||||
#define IPV6CTL_MAXFRAGSPERPACKET 53 /* Max fragments per packet */
|
||||
#define IPV6CTL_MAXFRAGBUCKETSIZE 54 /* Max reassembly queues per bucket */
|
||||
#define IPV6CTL_MAXID 55
|
||||
|
||||
#endif /* __BSD_VISIBLE */
|
||||
|
||||
/*
|
||||
|
|
|
|||
|
|
@ -418,7 +418,9 @@ VNET_DEFINE(int, ip6_no_radr) = 0;
|
|||
VNET_DEFINE(int, ip6_norbit_raif) = 0;
|
||||
VNET_DEFINE(int, ip6_rfc6204w3) = 0;
|
||||
VNET_DEFINE(int, ip6_maxfragpackets); /* initialized in frag6.c:frag6_init() */
|
||||
VNET_DEFINE(int, ip6_maxfrags); /* initialized in frag6.c:frag6_init() */
|
||||
int ip6_maxfrags; /* initialized in frag6.c:frag6_init() */
|
||||
VNET_DEFINE(int, ip6_maxfragbucketsize);/* initialized in frag6.c:frag6_init() */
|
||||
VNET_DEFINE(int, ip6_maxfragsperpacket); /* initialized in frag6.c:frag6_init() */
|
||||
VNET_DEFINE(int, ip6_log_interval) = 5;
|
||||
VNET_DEFINE(int, ip6_hdrnestlimit) = 15;/* How many header options will we
|
||||
* process? */
|
||||
|
|
@ -505,6 +507,20 @@ sysctl_ip6_tempvltime(SYSCTL_HANDLER_ARGS)
|
|||
return (0);
|
||||
}
|
||||
|
||||
static int
|
||||
sysctl_ip6_maxfragpackets(SYSCTL_HANDLER_ARGS)
|
||||
{
|
||||
int error, val;
|
||||
|
||||
val = V_ip6_maxfragpackets;
|
||||
error = sysctl_handle_int(oidp, &val, 0, req);
|
||||
if (error != 0 || !req->newptr)
|
||||
return (error);
|
||||
V_ip6_maxfragpackets = val;
|
||||
frag6_set_bucketsize();
|
||||
return (0);
|
||||
}
|
||||
|
||||
SYSCTL_INT(_net_inet6_ip6, IPV6CTL_FORWARDING, forwarding,
|
||||
CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_forwarding), 0,
|
||||
"Enable IPv6 forwarding between interfaces");
|
||||
|
|
@ -517,9 +533,12 @@ SYSCTL_INT(_net_inet6_ip6, IPV6CTL_DEFHLIM, hlim,
|
|||
SYSCTL_VNET_PCPUSTAT(_net_inet6_ip6, IPV6CTL_STATS, stats, struct ip6stat,
|
||||
ip6stat,
|
||||
"IP6 statistics (struct ip6stat, netinet6/ip6_var.h)");
|
||||
SYSCTL_INT(_net_inet6_ip6, IPV6CTL_MAXFRAGPACKETS, maxfragpackets,
|
||||
CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_maxfragpackets), 0,
|
||||
"Maximum allowed number of outstanding fragmented IPv6 packets");
|
||||
SYSCTL_PROC(_net_inet6_ip6, IPV6CTL_MAXFRAGPACKETS, maxfragpackets,
|
||||
CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW, NULL, 0,
|
||||
sysctl_ip6_maxfragpackets, "I",
|
||||
"Default maximum number of outstanding fragmented IPv6 packets. "
|
||||
"A value of 0 means no fragmented packets will be accepted, while a "
|
||||
"a value of -1 means no limit");
|
||||
SYSCTL_INT(_net_inet6_ip6, IPV6CTL_ACCEPT_RTADV, accept_rtadv,
|
||||
CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_accept_rtadv), 0,
|
||||
"Default value of per-interface flag for accepting ICMPv6 RA messages");
|
||||
|
|
@ -588,8 +607,16 @@ SYSCTL_INT(_net_inet6_ip6, IPV6CTL_USE_DEFAULTZONE, use_defaultzone,
|
|||
CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_use_defzone), 0,
|
||||
"Use the default scope zone when none is specified");
|
||||
SYSCTL_INT(_net_inet6_ip6, IPV6CTL_MAXFRAGS, maxfrags,
|
||||
CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_maxfrags), 0,
|
||||
"Maximum allowed number of outstanding IPv6 packet fragments");
|
||||
CTLFLAG_RW, &ip6_maxfrags, 0,
|
||||
"Maximum allowed number of outstanding IPv6 packet fragments. "
|
||||
"A value of 0 means no fragmented packets will be accepted, while a "
|
||||
"a value of -1 means no limit");
|
||||
SYSCTL_INT(_net_inet6_ip6, IPV6CTL_MAXFRAGBUCKETSIZE, maxfragbucketsize,
|
||||
CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_maxfragbucketsize), 0,
|
||||
"Maximum number of reassembly queues per hash bucket");
|
||||
SYSCTL_INT(_net_inet6_ip6, IPV6CTL_MAXFRAGSPERPACKET, maxfragsperpacket,
|
||||
CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_maxfragsperpacket), 0,
|
||||
"Maximum allowed number of fragments per packet");
|
||||
SYSCTL_INT(_net_inet6_ip6, IPV6CTL_MCAST_PMTU, mcast_pmtu,
|
||||
CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_mcast_pmtu), 0,
|
||||
"Enable path MTU discovery for multicast packets");
|
||||
|
|
|
|||
|
|
@ -296,8 +296,10 @@ VNET_DECLARE(struct socket *, ip6_mrouter); /* multicast routing daemon */
|
|||
VNET_DECLARE(int, ip6_sendredirects); /* send IP redirects when forwarding? */
|
||||
VNET_DECLARE(int, ip6_maxfragpackets); /* Maximum packets in reassembly
|
||||
* queue */
|
||||
VNET_DECLARE(int, ip6_maxfrags); /* Maximum fragments in reassembly
|
||||
extern int ip6_maxfrags; /* Maximum fragments in reassembly
|
||||
* queue */
|
||||
VNET_DECLARE(int, ip6_maxfragbucketsize); /* Maximum reassembly queues per bucket */
|
||||
VNET_DECLARE(int, ip6_maxfragsperpacket); /* Maximum fragments per packet */
|
||||
VNET_DECLARE(int, ip6_accept_rtadv); /* Acts as a host not a router */
|
||||
VNET_DECLARE(int, ip6_no_radr); /* No defroute from RA */
|
||||
VNET_DECLARE(int, ip6_norbit_raif); /* Disable R-bit in NA on RA
|
||||
|
|
@ -312,7 +314,8 @@ VNET_DECLARE(int, ip6_dad_count); /* DupAddrDetectionTransmits */
|
|||
#define V_ip6_mrouter VNET(ip6_mrouter)
|
||||
#define V_ip6_sendredirects VNET(ip6_sendredirects)
|
||||
#define V_ip6_maxfragpackets VNET(ip6_maxfragpackets)
|
||||
#define V_ip6_maxfrags VNET(ip6_maxfrags)
|
||||
#define V_ip6_maxfragbucketsize VNET(ip6_maxfragbucketsize)
|
||||
#define V_ip6_maxfragsperpacket VNET(ip6_maxfragsperpacket)
|
||||
#define V_ip6_accept_rtadv VNET(ip6_accept_rtadv)
|
||||
#define V_ip6_no_radr VNET(ip6_no_radr)
|
||||
#define V_ip6_norbit_raif VNET(ip6_norbit_raif)
|
||||
|
|
@ -399,6 +402,7 @@ int ip6_fragment(struct ifnet *, struct mbuf *, int, u_char, int,
|
|||
|
||||
int route6_input(struct mbuf **, int *, int);
|
||||
|
||||
void frag6_set_bucketsize(void);
|
||||
void frag6_init(void);
|
||||
int frag6_input(struct mbuf **, int *, int);
|
||||
void frag6_slowtimo(void);
|
||||
|
|
|
|||
Loading…
Reference in New Issue