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vr_proto_ip.c
1257 lines (1036 loc) · 34.9 KB
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vr_proto_ip.c
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/*
* vr_proto_ip.c -- IP protocol handling
*
* Copyright (c) 2013 Juniper Networks, Inc. All rights reserved.
*/
#include <vr_os.h>
#include <vr_types.h>
#include <vr_packet.h>
#include "vr_interface.h"
#include "vr_datapath.h"
#include "vr_mpls.h"
#include "vr_vxlan.h"
#include "vr_ip_mtrie.h"
#include "vr_fragment.h"
#include "vr_bridge.h"
static unsigned short vr_ip_id;
extern struct vr_vrf_stats *(*vr_inet_vrf_stats)(unsigned short, unsigned int);
extern struct vr_nexthop *vr_inet6_ip_lookup(unsigned short, uint8_t *);
unsigned short
vr_generate_unique_ip_id()
{
vr_ip_id++;
if (!vr_ip_id)
vr_ip_id++;
return vr_ip_id;
}
struct vr_nexthop *
vr_inet_ip_lookup(unsigned short vrf, uint32_t ip)
{
uint32_t rt_prefix;
struct vr_route_req rt;
rt.rtr_req.rtr_vrf_id = vrf;
rt.rtr_req.rtr_prefix = (uint8_t *)&rt_prefix;
*(uint32_t*)rt.rtr_req.rtr_prefix = ip;
rt.rtr_req.rtr_prefix_size = 4;
rt.rtr_req.rtr_prefix_len = IP4_PREFIX_LEN;
rt.rtr_req.rtr_family = AF_INET;
rt.rtr_req.rtr_marker_size = 0;
rt.rtr_req.rtr_nh_id = 0;
return vr_inet_route_lookup(vrf, &rt);
}
struct vr_nexthop *
vr_inet_src_lookup(unsigned short vrf, struct vr_packet *pkt)
{
struct vr_ip *ip;
struct vr_ip6 *ip6;
if (!pkt)
return NULL;
if (pkt->vp_type == VP_TYPE_IP) {
ip = (struct vr_ip *)pkt_network_header(pkt);
if (!ip)
return NULL;
return vr_inet_ip_lookup(vrf, ip->ip_saddr);
} else if (pkt->vp_type == VP_TYPE_IP6) {
ip6 = (struct vr_ip6 *)pkt_network_header(pkt);
if (!ip6)
return NULL;
return vr_inet6_ip_lookup(vrf, ip6->ip6_src);
}
return NULL;
}
static inline unsigned char
vr_ip_decrement_ttl(struct vr_ip *ip)
{
unsigned int diff = 0xfffe;
unsigned int csum;
csum = (~ip->ip_csum) & 0xffff;
csum += diff;
csum = (csum >> 16) + (csum & 0xffff);
if (csum >> 16)
csum = (csum & 0xffff) + 1;
--ip->ip_ttl;
ip->ip_csum = ~(csum & 0xffff);
return ip->ip_ttl;
}
void
vr_ip_update_csum(struct vr_packet *pkt, unsigned int ip_inc, unsigned int inc)
{
struct vr_ip *ip;
struct vr_tcp *tcp;
struct vr_udp *udp;
unsigned int csum;
unsigned short *csump;
ip = (struct vr_ip *)pkt_network_header(pkt);
ip->ip_csum = vr_ip_csum(ip);
if (ip->ip_proto == VR_IP_PROTO_TCP) {
tcp = (struct vr_tcp *)((unsigned char *)ip + ip->ip_hl * 4);
csump = &tcp->tcp_csum;
} else if (ip->ip_proto == VR_IP_PROTO_UDP) {
udp = (struct vr_udp *)((unsigned char *)ip + ip->ip_hl * 4);
csump = &udp->udp_csum;
} else {
return;
}
if (vr_ip_transport_header_valid(ip)) {
/*
* for partial checksums, the actual value is stored rather
* than the complement
*/
if (pkt->vp_flags & VP_FLAG_CSUM_PARTIAL) {
csum = (*csump) & 0xffff;
inc = ip_inc;
} else {
csum = ~(*csump) & 0xffff;
}
csum += inc;
if (csum < inc)
csum += 1;
csum = (csum & 0xffff) + (csum >> 16);
if (csum >> 16)
csum = (csum & 0xffff) + 1;
if (pkt->vp_flags & VP_FLAG_CSUM_PARTIAL) {
*csump = csum & 0xffff;
} else {
*csump = ~(csum) & 0xffff;
}
}
return;
}
unsigned short
vr_ip_csum(struct vr_ip *ip)
{
int sum = 0;
unsigned short *ptr = (unsigned short *)ip;
unsigned short answer = 0;
unsigned short *w = ptr;
int len = ip->ip_hl * 4;
int nleft = len;
ip->ip_csum = 0;
while (nleft > 1) {
sum += *w++;
nleft -= 2;
}
/* mop up an odd byte, if necessary */
if (nleft == 1) {
*(unsigned char *)(&answer) = *(unsigned char *)w;
sum += answer;
}
sum = (sum >> 16) + (sum & 0xFFFF);
sum += (sum >> 16);
answer = ~sum;
return answer;
}
unsigned short
vr_ip_partial_csum(struct vr_ip *ip)
{
unsigned long long s;
unsigned int sum;
unsigned short csum, proto;
proto = ip->ip_proto;
s = ip->ip_saddr;
s += ip->ip_daddr;
s += htons(ntohs(ip->ip_len) - (ip->ip_hl * 4));
s += htons(proto);
s = (s & 0xFFFFFFFF) + (s >> 32);
sum = (s & 0xFFFF) + (s >> 16);
csum = (sum & 0xFFFF) + (sum >> 16);
return csum;
}
int
vr_forward(struct vrouter *router, struct vr_packet *pkt,
struct vr_forwarding_md *fmd)
{
struct vr_route_req rt;
struct vr_nexthop *nh;
struct vr_ip *ip;
struct vr_ip6 *ip6, *outer_ip6;
struct vr_icmp *icmph;
struct vr_forwarding_md rt_fmd;
struct vr_interface *vif;
int family, status, encap_len = 0;
unsigned char ttl;
short plen;
uint32_t rt_prefix[4];
ip6 = NULL;
ip = (struct vr_ip *)pkt_data(pkt);
if (vr_ip_is_ip6(ip)) {
family = AF_INET6;
ip6 = (struct vr_ip6 *)pkt_data(pkt);
/* ttl = --ip6->ip6_hlim */
ttl = ip6->ip6_hlim;
pkt->vp_type = VP_TYPE_IP6;
} else if (vr_ip_is_ip4(ip)) {
family = AF_INET;
if (!ip->ip_ttl) {
vr_pfree(pkt, VP_DROP_TTL_EXCEEDED);
return 0;
}
ttl = vr_ip_decrement_ttl(ip);
pkt->vp_type = VP_TYPE_IP;
} else {
vr_pfree(pkt, VP_DROP_INVALID_PROTOCOL);
return 0;
}
pkt->vp_ttl = ttl;
rt.rtr_req.rtr_vrf_id = fmd->fmd_dvrf;
rt.rtr_req.rtr_family = family;
if (family == AF_INET) {
rt.rtr_req.rtr_prefix = (uint8_t*)&rt_prefix;
*(uint32_t*)rt.rtr_req.rtr_prefix = (ip->ip_daddr);
rt.rtr_req.rtr_prefix_size = 4;
rt.rtr_req.rtr_prefix_len = IP4_PREFIX_LEN;
} else {
rt.rtr_req.rtr_prefix = (uint8_t*)&rt_prefix;
rt.rtr_req.rtr_prefix_size = 16;
memcpy(rt.rtr_req.rtr_prefix, ip6->ip6_dst, 16);
rt.rtr_req.rtr_prefix_len = IP6_PREFIX_LEN;
}
rt.rtr_req.rtr_nh_id = 0;
rt.rtr_req.rtr_marker_size = 0;
nh = vr_inet_route_lookup(fmd->fmd_dvrf, &rt);
if (rt.rtr_req.rtr_label_flags & VR_RT_LABEL_VALID_FLAG) {
if (!fmd) {
vr_init_forwarding_md(&rt_fmd);
fmd = &rt_fmd;
}
vr_forwarding_md_set_label(fmd, rt.rtr_req.rtr_label,
VR_LABEL_TYPE_UNKNOWN);
}
vif = nh->nh_dev;
if (vif) {
if (vif->vif_type == VIF_TYPE_PHYSICAL) {
encap_len = sizeof(struct vr_eth) + sizeof(struct vr_ip)+ sizeof(struct vr_udp) +sizeof(unsigned int);
}
if (family == AF_INET) {
if ((ip->ip_frag_off & VR_IP_DF) &&
(vif->vif_mtu < (sizeof(struct vr_ip)+ip->ip_len+encap_len))) {
}
} else if (family == AF_INET6) {
plen = ntohs(ip6->ip6_plen);
/* Handle PMTU for inet6 */
if (vif->vif_mtu < (sizeof(struct vr_ip6)+plen+encap_len)) {
/*Send ICMP too big message */
if (pkt->vp_data < (sizeof(struct vr_ip6) + sizeof(struct vr_icmp))) {
/* Not enough head room to add ip6/icmpv6 headers*/
vr_pfree(pkt, VP_DROP_PUSH);
return 0;
}
icmph = (struct vr_icmp*) pkt_push(pkt, sizeof(struct vr_icmp));
icmph->icmp_type = VR_ICMP6_TYPE_PKT_TOO_BIG;
icmph->icmp_code = 0;
icmph->icmp_csum = 0;
icmph->icmp_eid = 0;
icmph->icmp_eseq = htons(vif->vif_mtu - encap_len); /*set MTU in lower bytes of second word*/
/* Build the outer header */
outer_ip6 = (struct vr_ip6*) pkt_push(pkt, sizeof(struct vr_ip6));
memset(outer_ip6, 0, sizeof(struct vr_ip6));
memcpy(outer_ip6, ip6, sizeof(struct vr_ip6));
memcpy(outer_ip6->ip6_dst, ip6->ip6_src, 16);
memcpy(outer_ip6->ip6_src, ip6->ip6_dst, 16);
outer_ip6->ip6_src[15] = 0xff; //Mimic the GW IP as the src IP
if (pkt->vp_if->vif_mtu >= (plen + 2*sizeof(struct vr_ip6)
+ sizeof(struct vr_icmp))) {
outer_ip6->ip6_plen = htons(plen + sizeof(struct vr_ip6) + sizeof(struct vr_icmp));
} else {
/* TODO: Chop the packet at the tail for the added header*/
}
/* Calculate ICMP6 checksum */
icmph->icmp_csum = ~(vr_icmp6_checksum(outer_ip6, icmph));
/* Update packet pointers, perform route lookup and forward */
pkt_set_network_header(pkt, pkt->vp_data);
memcpy(rt.rtr_req.rtr_prefix, outer_ip6->ip6_dst, 16);
nh = vr_inet_route_lookup(fmd->fmd_dvrf, &rt);
}
}
}
status = nh_output(pkt, nh, fmd);
return status;
}
unsigned int
vr_icmp_input(struct vrouter *router, struct vr_packet *pkt,
struct vr_forwarding_md *fmd)
{
int ret;
unsigned int offset = 0, pull_len = 0;
unsigned int unhandled = 1, handled = 0;
struct vr_icmp *icmph;
struct vr_ip *iph;
struct vr_udp *udph;
icmph = (struct vr_icmp *)(pkt_data(pkt) + offset);
pull_len += sizeof(*icmph);
if (vr_icmp_error(icmph)) {
pull_len += sizeof(*iph);
ret = vr_pkt_may_pull(pkt, pull_len);
if (ret)
return unhandled;
offset += sizeof(*icmph);
iph = (struct vr_ip *)(pkt_data(pkt) + offset);
if ((iph->ip_proto != VR_IP_PROTO_GRE) &&
(iph->ip_proto != VR_IP_PROTO_UDP))
return unhandled;
pull_len += ((iph->ip_hl * 4) - sizeof(*iph));
ret = vr_pkt_may_pull(pkt, pull_len);
if (ret)
return unhandled;
iph = (struct vr_ip *)(pkt_data(pkt) + offset);
if (iph->ip_proto == VR_IP_PROTO_UDP) {
/* for sport and dport */
pull_len += 4;
offset += (iph->ip_hl * 4);
ret = vr_pkt_may_pull(pkt, pull_len);
if (ret)
return unhandled;
/*
* Note - we can't look at any other data other than ports
* since we pull only the first 4 bytes
*/
udph = (struct vr_udp *)(pkt_data(pkt) + offset);
if (!vr_mpls_udp_port(ntohs(udph->udp_dport)))
return unhandled;
}
vr_trap(pkt, pkt->vp_if->vif_vrf, AGENT_TRAP_ICMP_ERROR, 0);
return handled;
}
return unhandled;
}
/*
* vr_udp_input - handle incoming UDP packets. If the UDP destination
* port is for MPLS over UDP or VXLAN, decap the packet and forward the inner
* packet. Returns 1 if the packet was not handled, 0 otherwise.
*/
unsigned int
vr_udp_input(struct vrouter *router, struct vr_packet *pkt,
struct vr_forwarding_md *fmd)
{
struct vr_udp *udph, udp;
int handled = 0, ret = PKT_RET_FAST_PATH;
unsigned short reason;
int encap_type = PKT_ENCAP_MPLS;
if (vr_perfp && vr_pull_inner_headers_fast) {
handled = vr_pull_inner_headers_fast(pkt, VR_IP_PROTO_UDP,
vr_mpls_tunnel_type, &ret, &encap_type);
if (!handled) {
return 1;
}
if (ret == PKT_RET_FAST_PATH) {
goto next_encap;
}
if (ret == PKT_RET_ERROR) {
vr_pfree(pkt, VP_DROP_CKSUM_ERR);
return 0;
}
/* Fall through to the slower path */
ASSERT(ret == PKT_RET_SLOW_PATH);
}
udph = (struct vr_udp *)vr_pheader_pointer(pkt, sizeof(struct vr_udp),
&udp);
if (udph == NULL) {
vr_pfree(pkt, VP_DROP_MISC);
return 0;
}
if (vr_mpls_udp_port(ntohs(udph->udp_dport))) {
encap_type = PKT_ENCAP_MPLS;
} else if (ntohs(udph->udp_dport) == VR_VXLAN_UDP_DST_PORT) {
encap_type = PKT_ENCAP_VXLAN;
} else {
return 1;
}
/*
* We are going to handle this packet. Pull as much of the inner packet
* as required into the contiguous part of the pkt.
*/
if (vr_pull_inner_headers) {
if (!vr_pull_inner_headers(pkt, VR_IP_PROTO_UDP,
&reason, vr_mpls_tunnel_type)) {
vr_pfree(pkt, reason);
return 0;
}
}
pkt_pull(pkt, sizeof(struct vr_udp));
next_encap:
if (encap_type == PKT_ENCAP_MPLS) {
vr_mpls_input(router, pkt, fmd);
} else {
vr_vxlan_input(router, pkt, fmd);
}
return 0;
}
unsigned int
vr_gre_input(struct vrouter *router, struct vr_packet *pkt,
struct vr_forwarding_md *fmd)
{
unsigned short *gre_hdr, gre_proto, hdr_len, reason;
char buf[4];
int handled = 0, ret = PKT_RET_FAST_PATH;
int encap_type;
if (vr_perfp && vr_pull_inner_headers_fast) {
handled = vr_pull_inner_headers_fast(pkt, VR_IP_PROTO_GRE,
vr_mpls_tunnel_type, &ret, &encap_type);
if (!handled) {
goto unhandled;
}
if (ret == PKT_RET_FAST_PATH) {
goto mpls_input;
}
if (ret == PKT_RET_ERROR) {
vr_pfree(pkt, VP_DROP_CKSUM_ERR);
return 0;
}
/* Fall through to the slower path */
ASSERT(ret == PKT_RET_SLOW_PATH);
}
/* start with basic GRE header */
hdr_len = 4;
gre_hdr = (unsigned short *) vr_pheader_pointer(pkt, hdr_len, buf);
if (gre_hdr == NULL) {
vr_pfree(pkt, VP_DROP_MISC);
return 0;
}
if (*gre_hdr & VR_GRE_FLAG_CSUM)
hdr_len += 4;
if (*gre_hdr & VR_GRE_FLAG_KEY)
hdr_len += 4;
/* we are not RFC 1701 compliant receiver */
if (*gre_hdr & (~(VR_GRE_FLAG_CSUM | VR_GRE_FLAG_KEY)))
goto unhandled;
/*
* ... and we do not deal with any other protocol other than MPLS
* for now
*/
gre_proto = ntohs(*(gre_hdr + 1));
if (gre_proto != VR_GRE_PROTO_MPLS)
goto unhandled;
/*
* We are going to handle this packet. Pull as much of the inner packet
* as required into the contiguous part of the pkt.
*/
if (vr_pull_inner_headers) {
if (!vr_pull_inner_headers(pkt, VR_IP_PROTO_GRE, &reason,
vr_mpls_tunnel_type)) {
vr_pfree(pkt, reason);
return 0;
}
}
/* pull and junk the GRE header */
pkt_pull(pkt, hdr_len);
mpls_input:
vr_mpls_input(router, pkt, fmd);
return 0;
unhandled:
return 1;
}
int
vr_ip_rcv(struct vrouter *router, struct vr_packet *pkt,
struct vr_forwarding_md *fmd)
{
struct vr_ip *ip;
struct vr_interface *vif = NULL;
unsigned char *l2_hdr;
unsigned int hlen;
unsigned short drop_reason, l4_port = 0;
int ret = 0, unhandled = 1;
struct vr_fragment *frag;
ip = (struct vr_ip *)pkt_data(pkt);
hlen = ip->ip_hl * 4;
pkt_pull(pkt, hlen);
/*
* this is a check to make sure that packets were indeed destined to
* me or not. there are two ways a packet can reach here. either through
*
* route lookup->receive nexthop->vr_ip_rcv or through
* VP_FLAG_TO_ME(NO route lookup(!vp->vp_nh))->vr_ip_rcv
*/
if ((pkt->vp_nh) || (vr_myip(pkt->vp_if, ip->ip_daddr))) {
if (ip->ip_proto == VR_IP_PROTO_GRE) {
unhandled = vr_gre_input(router, pkt, fmd);
} else if (ip->ip_proto == VR_IP_PROTO_UDP) {
unhandled = vr_udp_input(router, pkt, fmd);
} else if (ip->ip_proto == VR_IP_PROTO_ICMP) {
unhandled = vr_icmp_input(router, pkt, fmd);
}
}
if (unhandled) {
/*
* the gre, udp, icmp handlers could have pulled the packet. so
* reset the notion of ip header
*/
if (!(ip = (struct vr_ip *)pkt_push(pkt, hlen))) {
drop_reason = VP_DROP_PUSH;
goto drop_pkt;
}
/* ...and position the data back to l4 header */
pkt_pull(pkt, hlen);
if (pkt->vp_nh) {
vif = pkt->vp_nh->nh_dev;
/*
* If flow processing is already not done, relaxed policy
* enabled, not in cross connect mode, not mirror packet,
* lets subject it to flow processing.
*/
if (pkt->vp_nh->nh_flags & NH_FLAG_RELAXED_POLICY) {
if (!(pkt->vp_flags & VP_FLAG_FLOW_SET) &&
!(pkt->vp_flags & (VP_FLAG_TO_ME | VP_FLAG_FROM_DP))) {
if ((ip->ip_proto == VR_IP_PROTO_UDP) ||
(ip->ip_proto == VR_IP_PROTO_TCP)) {
if (vr_ip_transport_header_valid(ip)) {
l4_port = *(unsigned short *) (pkt_data(pkt) + 2);
} else {
frag = vr_fragment_get(router, fmd->fmd_dvrf, ip);
if (frag)
l4_port = frag->f_dport;
}
if (l4_port && vr_valid_link_local_port(router, AF_INET,
ip->ip_proto, ntohs(l4_port))) {
/* Force the flow lookup */
pkt->vp_flags |= VP_FLAG_FLOW_GET;
/* Get back the IP header */
if (!pkt_push(pkt, hlen)) {
drop_reason = VP_DROP_PUSH;
goto drop_pkt;
}
/* Subject it to flow for Linklocal */
if (!vr_flow_forward(router, pkt, fmd))
return 0;
if (!vr_l3_input(pkt, fmd)) {
drop_reason = VP_DROP_NOWHERE_TO_GO;
goto drop_pkt;
}
return 0;
}
}
}
}
}
if (!vif && !(vif = pkt->vp_if->vif_bridge) &&
!(vif = router->vr_host_if)) {
drop_reason = VP_DROP_TRAP_NO_IF;
goto drop_pkt;
}
if ((pkt->vp_flags & VP_FLAG_FROM_DP) ||
!vr_phead_len(pkt)) {
/* get the ip header back */
if (!pkt_push(pkt, hlen)) {
drop_reason = VP_DROP_PUSH;
goto drop_pkt;
}
/* push the l2 header */
l2_hdr = pkt_push(pkt, sizeof(vif->vif_rewrite));
if (!l2_hdr) {
drop_reason = VP_DROP_PUSH;
goto drop_pkt;
}
memcpy(l2_hdr, vif->vif_rewrite, sizeof(vif->vif_rewrite));
} else {
vr_preset(pkt);
}
ret = vif->vif_tx(vif, pkt, fmd);
}
return ret;
drop_pkt:
vr_pfree(pkt, drop_reason);
return 0;
}
flow_result_t
vr_inet_flow_nat(struct vr_flow_entry *fe, struct vr_packet *pkt,
struct vr_forwarding_md *fmd)
{
bool hdr_update = false;
unsigned int ip_inc, inc = 0;
unsigned short *t_sport, *t_dport;
struct vrouter *router = pkt->vp_if->vif_router;
struct vr_flow_entry *rfe;
struct vr_ip *ip, *icmp_pl_ip;
struct vr_icmp *icmph;
if (fe->fe_rflow < 0)
goto drop;
rfe = vr_get_flow_entry(router, fe->fe_rflow);
if (!rfe)
goto drop;
ip = (struct vr_ip *)pkt_network_header(pkt);
if (ip->ip_proto == VR_IP_PROTO_ICMP) {
icmph = (struct vr_icmp *)((unsigned char *)ip + (ip->ip_hl * 4));
if (vr_icmp_error(icmph)) {
icmp_pl_ip = (struct vr_ip *)(icmph + 1);
if (fe->fe_flags & VR_FLOW_FLAG_SNAT) {
icmp_pl_ip->ip_daddr = rfe->fe_key.flow4_dip;
hdr_update = true;
}
if (fe->fe_flags & VR_FLOW_FLAG_DNAT) {
icmp_pl_ip->ip_saddr = rfe->fe_key.flow4_sip;
hdr_update = true;
}
if (hdr_update)
icmp_pl_ip->ip_csum = vr_ip_csum(icmp_pl_ip);
t_sport = (unsigned short *)((unsigned char *)icmp_pl_ip +
(icmp_pl_ip->ip_hl * 4));
t_dport = t_sport + 1;
if (fe->fe_flags & VR_FLOW_FLAG_SPAT)
*t_dport = rfe->fe_key.flow4_dport;
if (fe->fe_flags & VR_FLOW_FLAG_DPAT)
*t_sport = rfe->fe_key.flow4_sport;
}
}
if ((fe->fe_flags & VR_FLOW_FLAG_SNAT) &&
(ip->ip_saddr == fe->fe_key.flow4_sip)) {
vr_incremental_diff(ip->ip_saddr, rfe->fe_key.flow4_dip, &inc);
ip->ip_saddr = rfe->fe_key.flow4_dip;
}
if (fe->fe_flags & VR_FLOW_FLAG_DNAT) {
vr_incremental_diff(ip->ip_daddr, rfe->fe_key.flow4_sip, &inc);
ip->ip_daddr = rfe->fe_key.flow4_sip;
}
ip_inc = inc;
if (vr_ip_transport_header_valid(ip)) {
t_sport = (unsigned short *)((unsigned char *)ip +
(ip->ip_hl * 4));
t_dport = t_sport + 1;
if (fe->fe_flags & VR_FLOW_FLAG_SPAT) {
vr_incremental_diff(*t_sport, rfe->fe_key.flow4_dport, &inc);
*t_sport = rfe->fe_key.flow4_dport;
}
if (fe->fe_flags & VR_FLOW_FLAG_DPAT) {
vr_incremental_diff(*t_dport, rfe->fe_key.flow4_sport, &inc);
*t_dport = rfe->fe_key.flow4_sport;
}
}
if (!vr_pkt_is_diag(pkt))
vr_ip_update_csum(pkt, ip_inc, inc);
if ((fe->fe_flags & VR_FLOW_FLAG_VRFT) && pkt->vp_nh &&
((pkt->vp_nh->nh_vrf != fmd->fmd_dvrf) ||
(pkt->vp_nh->nh_flags & NH_FLAG_ROUTE_LOOKUP))) {
/* only if pkt->vp_nh was set before... */
pkt->vp_nh = vr_inet_ip_lookup(fmd->fmd_dvrf, ip->ip_daddr);
}
return FLOW_FORWARD;
drop:
vr_pfree(pkt, VP_DROP_FLOW_NAT_NO_RFLOW);
return FLOW_CONSUMED;
}
static void
vr_inet_flow_swap(struct vr_flow *key_p)
{
unsigned short port;
unsigned int ipaddr;
port = key_p->flow4_sport;
key_p->flow4_sport = key_p->flow4_dport;
key_p->flow4_dport = port;
ipaddr = key_p->flow4_sip;
key_p->flow4_sip = key_p->flow4_dip;
key_p->flow4_dip = ipaddr;
return;
}
static unsigned short
vr_inet_flow_nexthop(struct vr_packet *pkt, unsigned short vlan)
{
unsigned short nh_id;
if (vif_is_fabric(pkt->vp_if) && pkt->vp_nh) {
/* this is more a requirement from agent */
if ((pkt->vp_nh->nh_type == NH_ENCAP)) {
nh_id = pkt->vp_nh->nh_dev->vif_nh_id;
} else {
nh_id = pkt->vp_nh->nh_id;
}
} else if (vif_is_service(pkt->vp_if)) {
nh_id = vif_vrf_table_get_nh(pkt->vp_if, vlan);
} else {
nh_id = pkt->vp_if->vif_nh_id;
}
return nh_id;
}
void
vr_inet_fill_flow(struct vr_flow *flow_p, unsigned short nh_id,
uint32_t sip, uint32_t dip, uint8_t proto,
uint16_t sport, uint16_t dport)
{
/* copy both source and destinations */
flow_p->flow4_sip = sip;
flow_p->flow4_dip = dip;
flow_p->flow4_proto = proto;
flow_p->flow4_nh_id = nh_id;
flow_p->flow4_sport = sport;
flow_p->flow4_dport = dport;
flow_p->key_len = sizeof(struct vr_inet_flow);
return;
}
static int
vr_inet_fragment_flow(struct vrouter *router, unsigned short vrf,
struct vr_packet *pkt, uint16_t vlan, struct vr_flow *flow_p)
{
uint16_t sport, dport;
unsigned short nh_id;
struct vr_fragment *frag;
struct vr_ip *ip = (struct vr_ip *)pkt_network_header(pkt);
frag = vr_fragment_get(router, vrf, ip);
if (!frag) {
return -1;
}
frag->f_received += (ntohs(ip->ip_len) - (ip->ip_hl * 4));
if (vr_ip_fragment_tail(ip)) {
frag->f_expected = ((ntohs(ip->ip_frag_off) & 0x1FFF) * 8) +
ntohs(ip->ip_len) - (ip->ip_hl * 4) ;
}
sport = frag->f_sport;
dport = frag->f_dport;
if (frag->f_received == frag->f_expected)
vr_fragment_del(frag);
nh_id = vr_inet_flow_nexthop(pkt, vlan);
vr_inet_fill_flow(flow_p, nh_id, ip->ip_saddr, ip->ip_daddr,
ip->ip_proto, sport, dport);
return 0;
}
bool
vr_inet_flow_allow_new_flow(struct vrouter *router, struct vr_packet *pkt)
{
struct vr_ip *iph = (struct vr_ip *)pkt_network_header(pkt);
if (vr_ip_fragment(iph) && !vr_ip_fragment_head(iph))
return false;
return true;
}
bool
vr_inet_flow_is_fat_flow(struct vrouter *router, struct vr_packet *pkt,
struct vr_flow_entry *fe)
{
if (!fe->fe_key.flow4_sport || !fe->fe_key.flow4_dport) {
if ((fe->fe_key.flow4_proto == VR_IP_PROTO_TCP) ||
(fe->fe_key.flow4_proto == VR_IP_PROTO_UDP) ||
(fe->fe_key.flow4_proto == VR_IP_PROTO_SCTP)) {
return true;
}
}
return false;
}
static int
vr_inet_proto_flow(struct vrouter *router, unsigned short vrf,
struct vr_packet *pkt, uint16_t vlan, struct vr_ip *ip,
struct vr_flow *flow_p)
{
int ret = 0;
unsigned short *t_hdr, sport, dport;
unsigned short nh_id;
struct vr_icmp *icmph;
fat_flow_port_mask_t port_mask;
t_hdr = (unsigned short *)((char *)ip + (ip->ip_hl * 4));
if (ip->ip_proto == VR_IP_PROTO_ICMP) {
icmph = (struct vr_icmp *)t_hdr;
if (vr_icmp_error(icmph)) {
/* we will generate a flow only for the first icmp error */
if ((unsigned char *)ip == pkt_network_header(pkt)) {
ret = vr_inet_proto_flow(router, vrf, pkt, vlan,
(struct vr_ip *)(icmph + 1), flow_p);
if (ret)
return ret;
vr_inet_flow_swap(flow_p);
} else {
/* for icmp error for icmp error, we will drop the packet */
return -1;
}
return 0;
} else if (vr_icmp_echo(icmph)) {
sport = icmph->icmp_eid;
dport = VR_ICMP_TYPE_ECHO_REPLY;
} else {
sport = 0;
dport = icmph->icmp_type;
}
} else if ((ip->ip_proto == VR_IP_PROTO_TCP) ||
(ip->ip_proto == VR_IP_PROTO_UDP)) {
sport = *t_hdr;
dport = *(t_hdr + 1);
} else {
sport = 0;
dport = 0;
}
port_mask = vr_flow_fat_flow_lookup(router, pkt, ip->ip_proto,
sport, dport);
switch (port_mask) {
case SOURCE_PORT_MASK:
sport = 0;
break;
case DESTINATION_PORT_MASK:
dport = 0;
break;
case ALL_PORT_MASK:
sport = dport = 0;
break;
default:
break;
}
nh_id = vr_inet_flow_nexthop(pkt, vlan);
vr_inet_fill_flow(flow_p, nh_id, ip->ip_saddr, ip->ip_daddr,
ip->ip_proto, sport, dport);
return 0;
}
int
vr_inet_form_flow(struct vrouter *router, unsigned short vrf,
struct vr_packet *pkt, uint16_t vlan, struct vr_flow *flow_p)
{
int ret;
struct vr_ip *ip = (struct vr_ip *)pkt_network_header(pkt);
if (vr_ip_transport_header_valid(ip)) {
ret = vr_inet_proto_flow(router, vrf, pkt, vlan, ip, flow_p);
} else {
ret = vr_inet_fragment_flow(router, vrf, pkt, vlan, flow_p);
}
return ret;
}
static bool
vr_inet_should_trap(struct vr_packet *pkt, struct vr_flow *flow_p)
{
uint32_t proto_port;
/*
* dhcp packet handling:
*
* for now we handle dhcp requests from only VMs and that too only
* for VMs that are not in the fabric VRF. dhcp refresh packets will
* anyway hit the route entry and get trapped from there.
*/
if (vif_is_virtual(pkt->vp_if) && vif_dhcp_enabled(pkt->vp_if)) {
proto_port = (flow_p->flow4_proto << VR_FLOW_PROTO_SHIFT) |
flow_p->flow4_sport;
if (proto_port == VR_UDP_DHCP_CPORT) {
return true;
}
}
return false;
}
flow_result_t
vr_inet_flow_lookup(struct vrouter *router, struct vr_packet *pkt,
struct vr_forwarding_md *fmd)
{
int ret;
bool lookup = false;
struct vr_flow flow, *flow_p = &flow;
struct vr_ip *ip = (struct vr_ip *)pkt_network_header(pkt);
struct vr_packet *pkt_c;
/*
* if the packet has already done one round of flow lookup, there
* is no point in doing it again, eh?
*/
if (pkt->vp_flags & VP_FLAG_FLOW_SET)
return FLOW_FORWARD;
/*
* if the interface is policy enabled, or if somebody else (eg:nexthop)