bool skb_flow_dissect(const struct sk_buff *skb, struct flow_keys *flow)
{
int poff, nhoff = skb_network_offset(skb);
u8 ip_proto;
__be16 proto = skb->protocol;
memset(flow, 0, sizeof(*flow));
again:
switch (proto) {
case __constant_htons(ETH_P_IP): {
const struct iphdr *iph;
struct iphdr _iph;
ip:
iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph);
if (!iph || iph->ihl < 5)
return false;
if (ip_is_fragment(iph))
ip_proto = 0;
else
ip_proto = iph->protocol;
iph_to_flow_copy_addrs(flow, iph);
nhoff += iph->ihl * 4;
break;
}
case __constant_htons(ETH_P_IPV6): {
const struct ipv6hdr *iph;
struct ipv6hdr _iph;
ipv6:
iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph);
if (!iph)
return false;
ip_proto = iph->nexthdr;
flow->src = iph->saddr.s6_addr32[3];
flow->dst = iph->daddr.s6_addr32[3];
nhoff += sizeof(struct ipv6hdr);
break;
}
case __constant_htons(ETH_P_8021Q): {
const struct vlan_hdr *vlan;
struct vlan_hdr _vlan;
vlan = skb_header_pointer(skb, nhoff, sizeof(_vlan), &_vlan);
if (!vlan)
return false;
proto = vlan->h_vlan_encapsulated_proto;
nhoff += sizeof(*vlan);
goto again;
}
case __constant_htons(ETH_P_PPP_SES): {
struct {
struct pppoe_hdr hdr;
__be16 proto;
} *hdr, _hdr;
hdr = skb_header_pointer(skb, nhoff, sizeof(_hdr), &_hdr);
if (!hdr)
return false;
proto = hdr->proto;
nhoff += PPPOE_SES_HLEN;
switch (proto) {
case __constant_htons(PPP_IP):
goto ip;
case __constant_htons(PPP_IPV6):
goto ipv6;
default:
return false;
}
}
default:
return false;
}
switch (ip_proto) {
case IPPROTO_GRE: {
struct gre_hdr {
__be16 flags;
__be16 proto;
} *hdr, _hdr;
hdr = skb_header_pointer(skb, nhoff, sizeof(_hdr), &_hdr);
if (!hdr)
return false;
if (!(hdr->flags & (GRE_VERSION|GRE_ROUTING))) {
proto = hdr->proto;
nhoff += 4;
if (hdr->flags & GRE_CSUM)
nhoff += 4;
if (hdr->flags & GRE_KEY)
nhoff += 4;
if (hdr->flags & GRE_SEQ)
nhoff += 4;
goto again;
}
break;
}
case IPPROTO_IPIP:
goto again;
default:
break;
}
flow->ip_proto = ip_proto;
poff = proto_ports_offset(ip_proto);
if (poff >= 0) {
__be32 *ports, _ports;
nhoff += poff;
ports = skb_header_pointer(skb, nhoff, sizeof(_ports), &_ports);
if (ports)
flow->ports = *ports;
}
return true;
}
/**
* __skb_flow_dissect - extract the flow_keys struct and return it
* @skb: sk_buff to extract the flow from, can be NULL if the rest are specified
* @data: raw buffer pointer to the packet, if NULL use skb->data
* @proto: protocol for which to get the flow, if @data is NULL use skb->protocol
* @nhoff: network header offset, if @data is NULL use skb_network_offset(skb)
* @hlen: packet header length, if @data is NULL use skb_headlen(skb)
*
* The function will try to retrieve the struct flow_keys from either the skbuff
* or a raw buffer specified by the rest parameters
*/
bool __skb_flow_dissect(const struct sk_buff *skb, struct flow_keys *flow,
void *data, __be16 proto, int nhoff, int hlen)
{
u8 ip_proto;
if (!data) {
data = skb->data;
proto = skb->protocol;
nhoff = skb_network_offset(skb);
hlen = skb_headlen(skb);
}
memset(flow, 0, sizeof(*flow));
again:
switch (proto) {
case htons(ETH_P_IP): {
const struct iphdr *iph;
struct iphdr _iph;
ip:
iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
if (!iph || iph->ihl < 5)
return false;
nhoff += iph->ihl * 4;
ip_proto = iph->protocol;
if (ip_is_fragment(iph))
ip_proto = 0;
/* skip the address processing if skb is NULL. The assumption
* here is that if there is no skb we are not looking for flow
* info but lengths and protocols.
*/
if (!skb)
break;
iph_to_flow_copy_addrs(flow, iph);
break;
}
case htons(ETH_P_IPV6): {
const struct ipv6hdr *iph;
struct ipv6hdr _iph;
__be32 flow_label;
ipv6:
iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
if (!iph)
return false;
ip_proto = iph->nexthdr;
nhoff += sizeof(struct ipv6hdr);
/* see comment above in IPv4 section */
if (!skb)
break;
flow->src = (__force __be32)ipv6_addr_hash(&iph->saddr);
flow->dst = (__force __be32)ipv6_addr_hash(&iph->daddr);
flow_label = ip6_flowlabel(iph);
if (flow_label) {
/* Awesome, IPv6 packet has a flow label so we can
* use that to represent the ports without any
* further dissection.
*/
flow->n_proto = proto;
flow->ip_proto = ip_proto;
flow->ports = flow_label;
flow->thoff = (u16)nhoff;
return true;
}
break;
}
case htons(ETH_P_8021AD):
case htons(ETH_P_8021Q): {
const struct vlan_hdr *vlan;
struct vlan_hdr _vlan;
vlan = __skb_header_pointer(skb, nhoff, sizeof(_vlan), data, hlen, &_vlan);
if (!vlan)
return false;
proto = vlan->h_vlan_encapsulated_proto;
nhoff += sizeof(*vlan);
goto again;
}
case htons(ETH_P_PPP_SES): {
struct {
struct pppoe_hdr hdr;
__be16 proto;
} *hdr, _hdr;
hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
if (!hdr)
return false;
proto = hdr->proto;
nhoff += PPPOE_SES_HLEN;
switch (proto) {
case htons(PPP_IP):
goto ip;
case htons(PPP_IPV6):
goto ipv6;
default:
return false;
}
}
case __constant_htons(ETH_P_MAP): {
struct {
struct rmnet_map_header_s map;
uint8_t proto;
} *map, _map;
unsigned int maplen;
map = skb_header_pointer(skb, nhoff, sizeof(_map), &_map);
if (!map)
return false;
/* Is MAP command? */
if (map->map.cd_bit)
return false;
/* Is aggregated frame? */
maplen = ntohs(map->map.pkt_len);
maplen += map->map.pad_len;
maplen += sizeof(struct rmnet_map_header_s);
if (maplen < skb->len)
return false;
nhoff += sizeof(struct rmnet_map_header_s);
switch (map->proto & RMNET_IP_VER_MASK) {
case RMNET_IPV4:
proto = htons(ETH_P_IP);
goto ip;
case RMNET_IPV6:
proto = htons(ETH_P_IPV6);
goto ipv6;
default:
return false;
}
}
case htons(ETH_P_FCOE):
flow->thoff = (u16)(nhoff + FCOE_HEADER_LEN);
/* fall through */
default:
return false;
}
switch (ip_proto) {
case IPPROTO_GRE: {
struct gre_hdr {
__be16 flags;
__be16 proto;
} *hdr, _hdr;
hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
if (!hdr)
return false;
/*
* Only look inside GRE if version zero and no
* routing
*/
if (!(hdr->flags & (GRE_VERSION|GRE_ROUTING))) {
proto = hdr->proto;
nhoff += 4;
if (hdr->flags & GRE_CSUM)
nhoff += 4;
if (hdr->flags & GRE_KEY)
nhoff += 4;
if (hdr->flags & GRE_SEQ)
nhoff += 4;
if (proto == htons(ETH_P_TEB)) {
const struct ethhdr *eth;
struct ethhdr _eth;
eth = __skb_header_pointer(skb, nhoff,
sizeof(_eth),
data, hlen, &_eth);
if (!eth)
return false;
proto = eth->h_proto;
nhoff += sizeof(*eth);
}
goto again;
}
break;
}
case IPPROTO_IPIP:
proto = htons(ETH_P_IP);
goto ip;
case IPPROTO_IPV6:
proto = htons(ETH_P_IPV6);
goto ipv6;
default:
break;
}
flow->n_proto = proto;
flow->ip_proto = ip_proto;
flow->thoff = (u16) nhoff;
/* unless skb is set we don't need to record port info */
if (skb)
flow->ports = __skb_flow_get_ports(skb, nhoff, ip_proto,
data, hlen);
return true;
}
static bool skb_flow_dissect(const struct sk_buff *skb, struct flow_keys *flow)
{
int nhoff = skb_network_offset(skb);
u8 ip_proto;
__be16 proto = skb->protocol;
memset(flow, 0, sizeof(*flow));
again:
switch (proto) {
case __constant_htons(ETH_P_IP): {
const struct iphdr *iph;
struct iphdr _iph;
ip:
iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph);
if (!iph)
return false;
if (ip_is_fragment(iph))
ip_proto = 0;
else
ip_proto = iph->protocol;
iph_to_flow_copy_addrs(flow, iph);
nhoff += iph->ihl * 4;
break;
}
case __constant_htons(ETH_P_IPV6): {
const struct ipv6hdr *iph;
struct ipv6hdr _iph;
ipv6:
iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph);
if (!iph)
return false;
ip_proto = iph->nexthdr;
flow->src = (__force __be32)ipv6_addr_hash(&iph->saddr);
flow->dst = (__force __be32)ipv6_addr_hash(&iph->daddr);
nhoff += sizeof(struct ipv6hdr);
break;
}
case __constant_htons(ETH_P_8021AD):
case __constant_htons(ETH_P_8021Q): {
const struct vlan_hdr *vlan;
struct vlan_hdr _vlan;
vlan = skb_header_pointer(skb, nhoff, sizeof(_vlan), &_vlan);
if (!vlan)
return false;
proto = vlan->h_vlan_encapsulated_proto;
nhoff += sizeof(*vlan);
goto again;
}
case __constant_htons(ETH_P_PPP_SES): {
struct {
struct pppoe_hdr hdr;
__be16 proto;
} *hdr, _hdr;
hdr = skb_header_pointer(skb, nhoff, sizeof(_hdr), &_hdr);
if (!hdr)
return false;
proto = hdr->proto;
nhoff += PPPOE_SES_HLEN;
switch (proto) {
case __constant_htons(PPP_IP):
goto ip;
case __constant_htons(PPP_IPV6):
goto ipv6;
default:
return false;
}
}
default:
return false;
}
switch (ip_proto) {
case IPPROTO_GRE: {
struct gre_hdr {
__be16 flags;
__be16 proto;
} *hdr, _hdr;
hdr = skb_header_pointer(skb, nhoff, sizeof(_hdr), &_hdr);
if (!hdr)
return false;
/*
* Only look inside GRE if version zero and no
* routing
*/
if (!(hdr->flags & (GRE_VERSION|GRE_ROUTING))) {
proto = hdr->proto;
nhoff += 4;
if (hdr->flags & GRE_CSUM)
nhoff += 4;
if (hdr->flags & GRE_KEY)
nhoff += 4;
if (hdr->flags & GRE_SEQ)
nhoff += 4;
if (proto == htons(ETH_P_TEB)) {
const struct ethhdr *eth;
struct ethhdr _eth;
eth = skb_header_pointer(skb, nhoff,
sizeof(_eth), &_eth);
if (!eth)
return false;
proto = eth->h_proto;
nhoff += sizeof(*eth);
}
goto again;
}
break;
}
case IPPROTO_IPIP:
goto again;
case IPPROTO_IPV6:
proto = htons(ETH_P_IPV6);
goto ipv6;
default:
break;
}
flow->ip_proto = ip_proto;
flow->ports = skb_flow_get_ports(skb, nhoff, ip_proto);
flow->thoff = (u16) nhoff;
return true;
}
bool skb_flow_dissect(const struct sk_buff *skb, struct flow_keys *flow)
{
int poff, nhoff = skb_network_offset(skb);
u8 ip_proto;
__be16 proto = skb->protocol;
memset(flow, 0, sizeof(*flow));
again:
switch (proto) {
case __constant_htons(ETH_P_IP): {
const struct iphdr *iph;
struct iphdr _iph;
ip:
iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph);
/* 2014-01-21 [email protected], LGE_DATA_google_security_patch [START] */
// refer to 'https://git.kernel.org/cgit/linux/kernel/git/davem/net.git/commit/?id=6f092343855a71e03b8d209815d8c45bf3a27fcd'
/* previous code
if (!iph)
*/
if (!iph || iph->ihl < 5)
/* 2014-01-21 [email protected], LGE_DATA_google_security_patch [END] */
return false;
if (ip_is_fragment(iph))
ip_proto = 0;
else
ip_proto = iph->protocol;
iph_to_flow_copy_addrs(flow, iph);
nhoff += iph->ihl * 4;
break;
}
case __constant_htons(ETH_P_IPV6): {
const struct ipv6hdr *iph;
struct ipv6hdr _iph;
ipv6:
iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph);
if (!iph)
return false;
ip_proto = iph->nexthdr;
flow->src = iph->saddr.s6_addr32[3];
flow->dst = iph->daddr.s6_addr32[3];
nhoff += sizeof(struct ipv6hdr);
break;
}
case __constant_htons(ETH_P_8021Q): {
const struct vlan_hdr *vlan;
struct vlan_hdr _vlan;
vlan = skb_header_pointer(skb, nhoff, sizeof(_vlan), &_vlan);
if (!vlan)
return false;
proto = vlan->h_vlan_encapsulated_proto;
nhoff += sizeof(*vlan);
goto again;
}
case __constant_htons(ETH_P_PPP_SES): {
struct {
struct pppoe_hdr hdr;
__be16 proto;
} *hdr, _hdr;
hdr = skb_header_pointer(skb, nhoff, sizeof(_hdr), &_hdr);
if (!hdr)
return false;
proto = hdr->proto;
nhoff += PPPOE_SES_HLEN;
switch (proto) {
case __constant_htons(PPP_IP):
goto ip;
case __constant_htons(PPP_IPV6):
goto ipv6;
default:
return false;
}
}
default:
return false;
}
switch (ip_proto) {
case IPPROTO_GRE: {
struct gre_hdr {
__be16 flags;
__be16 proto;
} *hdr, _hdr;
hdr = skb_header_pointer(skb, nhoff, sizeof(_hdr), &_hdr);
if (!hdr)
return false;
/*
* Only look inside GRE if version zero and no
* routing
*/
if (!(hdr->flags & (GRE_VERSION|GRE_ROUTING))) {
proto = hdr->proto;
nhoff += 4;
if (hdr->flags & GRE_CSUM)
nhoff += 4;
if (hdr->flags & GRE_KEY)
nhoff += 4;
if (hdr->flags & GRE_SEQ)
nhoff += 4;
goto again;
}
break;
}
case IPPROTO_IPIP:
goto again;
default:
break;
}
flow->ip_proto = ip_proto;
poff = proto_ports_offset(ip_proto);
if (poff >= 0) {
__be32 *ports, _ports;
ports = skb_header_pointer(skb, nhoff + poff,
sizeof(_ports), &_ports);
if (ports)
flow->ports = *ports;
}
return true;
}
