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Differential D5009 Diff 12537 sys/netinet/ip_fastfwd.c

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sys/netinet/ip_fastfwd.c

Show First 20 Lines • Show All 94 Lines • ▼ Show 20 Lines
#include <net/if_var.h> #include <net/if_var.h>
#include <net/if_dl.h> #include <net/if_dl.h>
#include <net/route.h> #include <net/route.h>
#include <net/vnet.h> #include <net/vnet.h>
#include <netinet/in.h> #include <netinet/in.h>
#include <netinet/in_kdtrace.h> #include <netinet/in_kdtrace.h>
#include <netinet/in_systm.h> #include <netinet/in_systm.h>
#include <netinet/in_fib.h>
#include <netinet/in_var.h> #include <netinet/in_var.h>
#include <netinet/ip.h> #include <netinet/ip.h>
#include <netinet/ip_var.h> #include <netinet/ip_var.h>
#include <netinet/ip_icmp.h> #include <netinet/ip_icmp.h>
#include <netinet/ip_options.h> #include <netinet/ip_options.h>
#include <net/rt_nhops.h>
#include <machine/in_cksum.h> #include <machine/in_cksum.h>
static struct sockaddr_in * static struct sockaddr_in *
ip_findroute(struct route *ro, struct in_addr dest, struct mbuf *m) ip_findroute(struct route *ro, struct in_addr dest, struct mbuf *m,
struct nhop_prepend *pnh)
{ {
struct sockaddr_in *dst; struct sockaddr_in *dst;
struct rtentry *rt; uint32_t hash;
int error;
/* /*
* Find route to destination. * Find route to destination.
*/ */
bzero(ro, sizeof(*ro)); bzero(ro, sizeof(*ro));
/* XXX: Temporary cast to until ro_rt rename */
ro->ro_rt = (struct rtentry *)pnh;
struct ip *ip;
ip = mtod(m, struct ip *);
hash = m->m_pkthdr.flowid;
error = fib4_lookup_prepend(M_GETFIB(m), dest, 0, hash, ro, NULL);
if (error == 0) {
dst = (struct sockaddr_in *)&ro->ro_dst; dst = (struct sockaddr_in *)&ro->ro_dst;
dst->sin_family = AF_INET; dst->sin_family = AF_INET;
dst->sin_len = sizeof(*dst); dst->sin_len = sizeof(*dst);
dst->sin_addr.s_addr = dest.s_addr; dst->sin_addr = pnh->nh4_addr;
in_rtalloc_ign(ro, 0, M_GETFIB(m)); return (dst);
}
/*
* Route there and interface still up?
*/
rt = ro->ro_rt;
if (rt && (rt->rt_flags & RTF_UP) &&
(rt->rt_ifp->if_flags & IFF_UP) &&
(rt->rt_ifp->if_drv_flags & IFF_DRV_RUNNING)) {
if (rt->rt_flags & RTF_GATEWAY)
dst = (struct sockaddr_in *)rt->rt_gateway;
} else {
IPSTAT_INC(ips_noroute); IPSTAT_INC(ips_noroute);
IPSTAT_INC(ips_cantforward); IPSTAT_INC(ips_cantforward);
if (rt)
RTFREE(rt);
icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0); icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0);
return NULL; return NULL;
} }
return dst;
}
/* /*
* Try to forward a packet based on the destination address. * Try to forward a packet based on the destination address.
* This is a fast path optimized for the plain forwarding case. * This is a fast path optimized for the plain forwarding case.
* If the packet is handled (and consumed) here then we return NULL; * If the packet is handled (and consumed) here then we return NULL;
* otherwise mbuf is returned and the packet should be delivered * otherwise mbuf is returned and the packet should be delivered
* to ip_input for full processing. * to ip_input for full processing.
*/ */
struct mbuf * struct mbuf *
ip_tryforward(struct mbuf *m) ip_tryforward(struct mbuf *m)
{ {
struct ip *ip; struct ip *ip;
struct mbuf *m0 = NULL; struct mbuf *m0 = NULL;
struct route ro; struct route ro;
struct sockaddr_in *dst = NULL; struct sockaddr_in *dst = NULL;
struct ifnet *ifp; struct ifnet *ifp;
struct in_addr odest, dest; struct in_addr odest, dest;
uint16_t ip_len, ip_off; uint16_t ip_len, ip_off;
int error = 0; int error = 0;
int mtu; int mtu;
struct nhop_prepend nh;
struct m_tag *fwd_tag = NULL; struct m_tag *fwd_tag = NULL;
/* /*
* Are we active and forwarding packets? * Are we active and forwarding packets?
*/ */
M_ASSERTVALID(m); M_ASSERTVALID(m);
M_ASSERTPKTHDR(m); M_ASSERTPKTHDR(m);
▲ Show 20 Lines • Show All 127 Lines • ▼ Show 20 Lines else
ip->ip_sum += htons(IPTTLDEC << 8); ip->ip_sum += htons(IPTTLDEC << 8);
#ifdef IPSTEALTH #ifdef IPSTEALTH
} }
#endif #endif
/* /*
* Find route to destination. * Find route to destination.
*/ */
if ((dst = ip_findroute(&ro, dest, m)) == NULL) if ((dst = ip_findroute(&ro, dest, m, &nh)) == NULL)
return NULL; /* icmp unreach already sent */ return NULL; /* icmp unreach already sent */
ifp = ro.ro_rt->rt_ifp; ifp = nh.nh_lifp;
/* /*
* Immediately drop blackholed traffic, and directed broadcasts * Immediately drop blackholed traffic, and directed broadcasts
* for either the all-ones or all-zero subnet addresses on * for either the all-ones or all-zero subnet addresses on
* locally attached networks. * locally attached networks.
*/ */
if ((ro.ro_rt->rt_flags & (RTF_BLACKHOLE|RTF_BROADCAST)) != 0) if ((nh.nh_flags & (NHF_BLACKHOLE|NHF_BROADCAST)) != 0)
goto drop; goto drop;
/* /*
* Step 5: outgoing firewall packet processing * Step 5: outgoing firewall packet processing
*/ */
/* /*
* Run through list of hooks for output packets. * Run through list of hooks for output packets.
Show All 21 Lines if (odest.s_addr != dest.s_addr || fwd_tag != NULL) {
* Is it now for a local address on this host? * Is it now for a local address on this host?
*/ */
if (m->m_flags & M_FASTFWD_OURS || in_localip(dest)) { if (m->m_flags & M_FASTFWD_OURS || in_localip(dest)) {
forwardlocal: forwardlocal:
/* /*
* Return packet for processing by ip_input(). * Return packet for processing by ip_input().
*/ */
m->m_flags |= M_FASTFWD_OURS; m->m_flags |= M_FASTFWD_OURS;
if (ro.ro_rt) if (ro.ro_rt) {
RTFREE(ro.ro_rt); fib4_free_prepend(&nh);
ro.ro_rt = NULL;
}
return m; return m;
} }
/* /*
* Redo route lookup with new destination address * Redo route lookup with new destination address
*/ */
if (fwd_tag) { if (fwd_tag) {
dest.s_addr = ((struct sockaddr_in *) dest.s_addr = ((struct sockaddr_in *)
(fwd_tag + 1))->sin_addr.s_addr; (fwd_tag + 1))->sin_addr.s_addr;
m_tag_delete(m, fwd_tag); m_tag_delete(m, fwd_tag);
m->m_flags &= ~M_IP_NEXTHOP; m->m_flags &= ~M_IP_NEXTHOP;
} }
RTFREE(ro.ro_rt); fib4_free_prepend(&nh);
if ((dst = ip_findroute(&ro, dest, m)) == NULL) ro.ro_rt = NULL;
if ((dst = ip_findroute(&ro, dest, m, &nh)) == NULL)
return NULL; /* icmp unreach already sent */ return NULL; /* icmp unreach already sent */
ifp = ro.ro_rt->rt_ifp; ifp = nh.nh_lifp;
} }
passout: passout:
/* /*
* Step 6: send off the packet * Step 6: send off the packet
*/ */
ip_len = ntohs(ip->ip_len); ip_len = ntohs(ip->ip_len);
ip_off = ntohs(ip->ip_off); ip_off = ntohs(ip->ip_off);
/* /*
* Check if route is dampned (when ARP is unable to resolve) * Check if route is dampned (when ARP is unable to resolve)
*/ */
if ((ro.ro_rt->rt_flags & RTF_REJECT) && if (nh.nh_flags & NHF_REJECT) {
(ro.ro_rt->rt_expire == 0 || time_uptime < ro.ro_rt->rt_expire)) {
icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0); icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0);
goto consumed; goto consumed;
} }
/* /*
* Check if media link state of interface is not down * Check if media link state of interface is not down
*/ */
if (ifp->if_link_state == LINK_STATE_DOWN) { if (ifp->if_link_state == LINK_STATE_DOWN) {
icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0); icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0);
goto consumed; goto consumed;
} }
/* /*
* Check if packet fits MTU or if hardware will fragment for us * Check if packet fits MTU or if hardware will fragment for us
*/ */
if (ro.ro_rt->rt_mtu) mtu = nh.nh_mtu;
mtu = min(ro.ro_rt->rt_mtu, ifp->if_mtu);
else
mtu = ifp->if_mtu;
if (ip_len <= mtu) { if (ip_len <= mtu) {
/* /*
* Avoid confusing lower layers. * Avoid confusing lower layers.
*/ */
m_clrprotoflags(m); m_clrprotoflags(m);
/* /*
* Send off the packet via outgoing interface * Send off the packet via outgoing interface
*/ */
▲ Show 20 Lines • Show All 44 Lines • ▼ Show 20 Lines if (ip_off & IP_DF) {
} else } else
IPSTAT_INC(ips_fragmented); IPSTAT_INC(ips_fragmented);
} }
} }
if (error != 0) if (error != 0)
IPSTAT_INC(ips_odropped); IPSTAT_INC(ips_odropped);
else { else {
counter_u64_add(ro.ro_rt->rt_pksent, 1);
IPSTAT_INC(ips_forward); IPSTAT_INC(ips_forward);
IPSTAT_INC(ips_fastforward); IPSTAT_INC(ips_fastforward);
} }
consumed: consumed:
RTFREE(ro.ro_rt); fib4_free_prepend(&nh);
return NULL; return NULL;
drop: drop:
if (m) if (m)
m_freem(m); m_freem(m);
if (ro.ro_rt) if (ro.ro_rt)
RTFREE(ro.ro_rt); fib4_free_prepend(&nh);
return NULL; return NULL;
} }