Differential D27166 Diff 79475 sys/netinet/ip_fastfwd.c

Changeset View

Standalone View

sys/netinet/ip_fastfwd.c

Show First 20 Lines • Show All 105 Lines • ▼ Show 20 Lines
#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 <machine/in_cksum.h>		#include <machine/in_cksum.h>

		#define V_ipsendredirects VNET(ipsendredirects)
		aeUnsubmitted Not Done Inline Actions It is already defined in ip_var.h. ae: It is already defined in ip_var.h.
		gnnAuthorUnsubmitted Done Inline Actions It is declared in ip_var.h but we need to access it here so we have this #define. gnn: It is declared in ip_var.h but we need to access it here so we have this #define.
		aeUnsubmitted Not Done Inline Actions I meant it is already defined in ip_var.h and ip_var.h is included in this file. ae: I meant it is already defined in ip_var.h and ip_var.h is included in this file.

		static struct mbuf *
		ip_redir_alloc(struct mbuf m, struct nhop_object nh,
		struct ip ip, in_addr_t addr)
		{
		struct mbuf *mcopy = m_gethdr(M_NOWAIT, m->m_type);
		if (mcopy != NULL && !m_dup_pkthdr(mcopy, m, M_NOWAIT)) {
		aeUnsubmitted Not Done Inline Actions We still going to the panic in case when m_gethdr() returns NULL. This condition shoud be if (mcopy == NULL \|\| m_dup_pkthdr() == 0) ae: We still going to the panic in case when m_gethdr() returns NULL. This condition shoud be ```…
		/*
		* It's probably ok if the pkthdr dup fails (because
		* the deep copy of the tag chain failed), but for now
		* be conservative and just discard the copy since
		* code below may some day want the tags.
		*/
		m_free(mcopy);
		return (NULL);
		}
		mcopy->m_len = min(ntohs(ip->ip_len), M_TRAILINGSPACE(mcopy));
		mcopy->m_pkthdr.len = mcopy->m_len;
		m_copydata(m, 0, mcopy->m_len, mtod(mcopy, caddr_t));

		if (nh != NULL &&
		melifaroUnsubmitted Not Done Inline Actions Nit: nh is always != NULL, as we return if `ip_findroute()` returns error. melifaro: Nit: nh is always != NULL, as we return if `ip_findroute()` returns error.
		((nh->nh_flags & (NHF_REDIRECT\|NHF_DEFAULT)) == 0)) {
		struct in_ifaddr nh_ia = (struct in_ifaddr )(nh->nh_ifa);
		u_long src = ntohl(ip->ip_src.s_addr);

		if (nh_ia != NULL && (src & nh_ia->ia_subnetmask) == nh_ia->ia_subnet) {
		if (nh->nh_flags & NHF_GATEWAY)
		*addr = nh->gw4_sa.sin_addr.s_addr;
		else
		*addr = ip->ip_dst.s_addr;
		}
		}
		return (mcopy);
		}


static int		static int
ip_findroute(struct nhop_object *pnh, struct in_addr dest, struct mbuf m)		ip_findroute(struct nhop_object *pnh, struct in_addr dest, struct mbuf m)
{		{
struct nhop_object *nh;		struct nhop_object *nh;

nh = fib4_lookup(M_GETFIB(m), dest, 0, NHR_NONE,		nh = fib4_lookup(M_GETFIB(m), dest, 0, NHR_NONE,
m->m_pkthdr.flowid);		m->m_pkthdr.flowid);
if (nh == NULL) {		if (nh == NULL) {
Show All 29 Lines
* 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 nhop_object *nh;		struct nhop_object *nh = NULL;
struct sockaddr_in dst;		struct sockaddr_in dst;
struct in_addr dest, odest, rtdest;		struct in_addr dest, odest, rtdest;
uint16_t ip_len, ip_off;		uint16_t ip_len, ip_off;
int error = 0;		int error = 0;
struct m_tag *fwd_tag = NULL;		struct m_tag *fwd_tag = NULL;
		struct mbuf *mcopy = NULL;
		struct in_addr redest;
/*		/*
* Are we active and forwarding packets?		* Are we active and forwarding packets?
*/		*/

M_ASSERTVALID(m);		M_ASSERTVALID(m);
M_ASSERTPKTHDR(m);		M_ASSERTPKTHDR(m);

#ifdef ALTQ		#ifdef ALTQ
▲ Show 20 Lines • Show All 208 Lines • ▼ Show 20 Lines	passout:
dst.sin_family = AF_INET;		dst.sin_family = AF_INET;
dst.sin_len = sizeof(dst);		dst.sin_len = sizeof(dst);
if (nh->nh_flags & NHF_GATEWAY)		if (nh->nh_flags & NHF_GATEWAY)
dst.sin_addr = nh->gw4_sa.sin_addr;		dst.sin_addr = nh->gw4_sa.sin_addr;
else		else
dst.sin_addr = dest;		dst.sin_addr = dest;

/*		/*
		* Handle redirect case.
		*/
		redest.s_addr = 0;
		if (V_ipsendredirects && (nh->nh_ifp == m->m_pkthdr.rcvif))
		mcopy = ip_redir_alloc(m, nh, ip, &redest.s_addr);
		melifaroUnsubmitted Not Done Inline Actions Would it be possible to move all of the code under condition here in a separate function? melifaro: Would it be possible to move all of the code under condition here in a separate function?
		gnnAuthorUnsubmitted Done Inline Actions I'd prefer to do that both here and in ip_input, in a followup, cleanup change. gnn: I'd prefer to do that both here and in ip_input, in a followup, cleanup change.
		melifaroUnsubmitted Done Inline Actions Given the change is mostly about adding this piece of code, it would be beneficial to start with "cleaned up" version :-) melifaro: Given the change is mostly about adding this piece of code, it would be beneficial to start…

		/*
* 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 (ip_len <= nh->nh_mtu) {		if (ip_len <= nh->nh_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
*/		*/
		aeUnsubmitted Done Inline Actions NULL pointer dereference is possible here in case, when m_gethdr() returns NULL. ae: NULL pointer dereference is possible here in case, when m_gethdr() returns NULL.
IP_PROBE(send, NULL, NULL, ip, nh->nh_ifp, ip, NULL);		IP_PROBE(send, NULL, NULL, ip, nh->nh_ifp, ip, NULL);
error = (*nh->nh_ifp->if_output)(nh->nh_ifp, m,		error = (*nh->nh_ifp->if_output)(nh->nh_ifp, m,
(struct sockaddr *)&dst, NULL);		(struct sockaddr *)&dst, NULL);
} else {		} else {
		aeUnsubmitted Done Inline Actions It seem nh here can not be NULL. ae: It seem nh here can not be NULL.
/*		/*
* Handle EMSGSIZE with icmp reply needfrag for TCP MTU discovery		* Handle EMSGSIZE with icmp reply needfrag for TCP MTU discovery
*/		*/
if (ip_off & IP_DF) {		if (ip_off & IP_DF) {
IPSTAT_INC(ips_cantfrag);		IPSTAT_INC(ips_cantfrag);
icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_NEEDFRAG,		icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_NEEDFRAG,
0, nh->nh_mtu);		0, nh->nh_mtu);
goto consumed;		goto consumed;
Show All 38 Lines	passout:
}		}

if (error != 0)		if (error != 0)
IPSTAT_INC(ips_odropped);		IPSTAT_INC(ips_odropped);
else {		else {
IPSTAT_INC(ips_forward);		IPSTAT_INC(ips_forward);
IPSTAT_INC(ips_fastforward);		IPSTAT_INC(ips_fastforward);
}		}

		/* Send required redirect */
		if (mcopy != NULL) {
		icmp_error(mcopy, ICMP_REDIRECT, ICMP_REDIRECT_HOST, redest.s_addr, 0);
		mcopy = NULL; /* Freed by caller */
		}

consumed:		consumed:
		if (mcopy != NULL)
		m_freem(mcopy);
return NULL;		return NULL;
drop:		drop:
if (m)		if (m)
m_freem(m);		m_freem(m);
return NULL;		return NULL;
}		}