413 lines
10 KiB
C
413 lines
10 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* Copyright (C) 2021-2022 Intel Corporation
|
|
*/
|
|
|
|
#include <uapi/linux/if_ether.h>
|
|
#include <uapi/linux/if_arp.h>
|
|
#include <uapi/linux/icmp.h>
|
|
|
|
#include <linux/etherdevice.h>
|
|
#include <linux/netdevice.h>
|
|
#include <linux/skbuff.h>
|
|
#include <linux/ieee80211.h>
|
|
|
|
#include <net/cfg80211.h>
|
|
#include <net/ip.h>
|
|
|
|
#include <linux/if_arp.h>
|
|
#include <linux/icmp.h>
|
|
#include <linux/udp.h>
|
|
#include <linux/ip.h>
|
|
#include <linux/mm.h>
|
|
|
|
#include "internal.h"
|
|
#include "sap.h"
|
|
#include "iwl-mei.h"
|
|
|
|
/*
|
|
* Returns true if further filtering should be stopped. Only in that case
|
|
* pass_to_csme and rx_handler_res are set. Otherwise, next level of filters
|
|
* should be checked.
|
|
*/
|
|
static bool iwl_mei_rx_filter_eth(const struct ethhdr *ethhdr,
|
|
const struct iwl_sap_oob_filters *filters,
|
|
bool *pass_to_csme,
|
|
rx_handler_result_t *rx_handler_res)
|
|
{
|
|
const struct iwl_sap_eth_filter *filt;
|
|
|
|
/* This filter is not relevant for UCAST packet */
|
|
if (!is_multicast_ether_addr(ethhdr->h_dest) ||
|
|
is_broadcast_ether_addr(ethhdr->h_dest))
|
|
return false;
|
|
|
|
for (filt = &filters->eth_filters[0];
|
|
filt < &filters->eth_filters[0] + ARRAY_SIZE(filters->eth_filters);
|
|
filt++) {
|
|
/* Assume there are no enabled filter after a disabled one */
|
|
if (!(filt->flags & SAP_ETH_FILTER_ENABLED))
|
|
break;
|
|
|
|
if (compare_ether_header(filt->mac_address, ethhdr->h_dest))
|
|
continue;
|
|
|
|
/* Packet needs to reach the host's stack */
|
|
if (filt->flags & SAP_ETH_FILTER_COPY)
|
|
*rx_handler_res = RX_HANDLER_PASS;
|
|
else
|
|
*rx_handler_res = RX_HANDLER_CONSUMED;
|
|
|
|
/* We have an authoritative answer, stop filtering */
|
|
if (filt->flags & SAP_ETH_FILTER_STOP) {
|
|
*pass_to_csme = true;
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
/* MCAST frames that don't match layer 2 filters are not sent to ME */
|
|
*pass_to_csme = false;
|
|
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Returns true iff the frame should be passed to CSME in which case
|
|
* rx_handler_res is set.
|
|
*/
|
|
static bool iwl_mei_rx_filter_arp(struct sk_buff *skb,
|
|
const struct iwl_sap_oob_filters *filters,
|
|
rx_handler_result_t *rx_handler_res)
|
|
{
|
|
const struct iwl_sap_ipv4_filter *filt = &filters->ipv4_filter;
|
|
const struct arphdr *arp;
|
|
const __be32 *target_ip;
|
|
u32 flags = le32_to_cpu(filt->flags);
|
|
|
|
if (!pskb_may_pull(skb, arp_hdr_len(skb->dev)))
|
|
return false;
|
|
|
|
arp = arp_hdr(skb);
|
|
|
|
/* Handle only IPv4 over ethernet ARP frames */
|
|
if (arp->ar_hrd != htons(ARPHRD_ETHER) ||
|
|
arp->ar_pro != htons(ETH_P_IP))
|
|
return false;
|
|
|
|
/*
|
|
* After the ARP header, we have:
|
|
* src MAC address - 6 bytes
|
|
* src IP address - 4 bytes
|
|
* target MAC addess - 6 bytes
|
|
*/
|
|
target_ip = (const void *)((const u8 *)(arp + 1) +
|
|
ETH_ALEN + sizeof(__be32) + ETH_ALEN);
|
|
|
|
/*
|
|
* ARP request is forwarded to ME only if IP address match in the
|
|
* ARP request's target ip field.
|
|
*/
|
|
if (arp->ar_op == htons(ARPOP_REQUEST) &&
|
|
(filt->flags & cpu_to_le32(SAP_IPV4_FILTER_ARP_REQ_PASS)) &&
|
|
(filt->ipv4_addr == 0 || filt->ipv4_addr == *target_ip)) {
|
|
if (flags & SAP_IPV4_FILTER_ARP_REQ_COPY)
|
|
*rx_handler_res = RX_HANDLER_PASS;
|
|
else
|
|
*rx_handler_res = RX_HANDLER_CONSUMED;
|
|
|
|
return true;
|
|
}
|
|
|
|
/* ARP reply is always forwarded to ME regardless of the IP */
|
|
if (flags & SAP_IPV4_FILTER_ARP_RESP_PASS &&
|
|
arp->ar_op == htons(ARPOP_REPLY)) {
|
|
if (flags & SAP_IPV4_FILTER_ARP_RESP_COPY)
|
|
*rx_handler_res = RX_HANDLER_PASS;
|
|
else
|
|
*rx_handler_res = RX_HANDLER_CONSUMED;
|
|
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
static bool
|
|
iwl_mei_rx_filter_tcp_udp(struct sk_buff *skb, bool ip_match,
|
|
const struct iwl_sap_oob_filters *filters,
|
|
rx_handler_result_t *rx_handler_res)
|
|
{
|
|
const struct iwl_sap_flex_filter *filt;
|
|
|
|
for (filt = &filters->flex_filters[0];
|
|
filt < &filters->flex_filters[0] + ARRAY_SIZE(filters->flex_filters);
|
|
filt++) {
|
|
if (!(filt->flags & SAP_FLEX_FILTER_ENABLED))
|
|
break;
|
|
|
|
/*
|
|
* We are required to have a match on the IP level and we didn't
|
|
* have such match.
|
|
*/
|
|
if ((filt->flags &
|
|
(SAP_FLEX_FILTER_IPV4 | SAP_FLEX_FILTER_IPV6)) &&
|
|
!ip_match)
|
|
continue;
|
|
|
|
if ((filt->flags & SAP_FLEX_FILTER_UDP) &&
|
|
ip_hdr(skb)->protocol != IPPROTO_UDP)
|
|
continue;
|
|
|
|
if ((filt->flags & SAP_FLEX_FILTER_TCP) &&
|
|
ip_hdr(skb)->protocol != IPPROTO_TCP)
|
|
continue;
|
|
|
|
/*
|
|
* We must have either a TCP header or a UDP header, both
|
|
* starts with a source port and then a destination port.
|
|
* Both are big endian words.
|
|
* Use a UDP header and that will work for TCP as well.
|
|
*/
|
|
if ((filt->src_port && filt->src_port != udp_hdr(skb)->source) ||
|
|
(filt->dst_port && filt->dst_port != udp_hdr(skb)->dest))
|
|
continue;
|
|
|
|
if (filt->flags & SAP_FLEX_FILTER_COPY)
|
|
*rx_handler_res = RX_HANDLER_PASS;
|
|
else
|
|
*rx_handler_res = RX_HANDLER_CONSUMED;
|
|
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
static bool iwl_mei_rx_filter_ipv4(struct sk_buff *skb,
|
|
const struct iwl_sap_oob_filters *filters,
|
|
rx_handler_result_t *rx_handler_res)
|
|
{
|
|
const struct iwl_sap_ipv4_filter *filt = &filters->ipv4_filter;
|
|
const struct iphdr *iphdr;
|
|
unsigned int iphdrlen;
|
|
bool match;
|
|
|
|
if (!pskb_may_pull(skb, skb_network_offset(skb) + sizeof(*iphdr)) ||
|
|
!pskb_may_pull(skb, skb_network_offset(skb) + ip_hdrlen(skb)))
|
|
return false;
|
|
|
|
iphdrlen = ip_hdrlen(skb);
|
|
iphdr = ip_hdr(skb);
|
|
match = !filters->ipv4_filter.ipv4_addr ||
|
|
filters->ipv4_filter.ipv4_addr == iphdr->daddr;
|
|
|
|
skb_set_transport_header(skb, skb_network_offset(skb) + iphdrlen);
|
|
|
|
switch (ip_hdr(skb)->protocol) {
|
|
case IPPROTO_UDP:
|
|
case IPPROTO_TCP:
|
|
/*
|
|
* UDP header is shorter than TCP header and we look at the first bytes
|
|
* of the header anyway (see below).
|
|
* If we have a truncated TCP packet, let CSME handle this.
|
|
*/
|
|
if (!pskb_may_pull(skb, skb_transport_offset(skb) +
|
|
sizeof(struct udphdr)))
|
|
return false;
|
|
|
|
return iwl_mei_rx_filter_tcp_udp(skb, match,
|
|
filters, rx_handler_res);
|
|
|
|
case IPPROTO_ICMP: {
|
|
struct icmphdr *icmp;
|
|
|
|
if (!pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(*icmp)))
|
|
return false;
|
|
|
|
icmp = icmp_hdr(skb);
|
|
|
|
/*
|
|
* Don't pass echo requests to ME even if it wants it as we
|
|
* want the host to answer.
|
|
*/
|
|
if ((filt->flags & cpu_to_le32(SAP_IPV4_FILTER_ICMP_PASS)) &&
|
|
match && (icmp->type != ICMP_ECHO || icmp->code != 0)) {
|
|
if (filt->flags & cpu_to_le32(SAP_IPV4_FILTER_ICMP_COPY))
|
|
*rx_handler_res = RX_HANDLER_PASS;
|
|
else
|
|
*rx_handler_res = RX_HANDLER_CONSUMED;
|
|
|
|
return true;
|
|
}
|
|
break;
|
|
}
|
|
case IPPROTO_ICMPV6:
|
|
/* TODO: Should we have the same ICMP request logic here too? */
|
|
if ((filters->icmpv6_flags & cpu_to_le32(SAP_ICMPV6_FILTER_ENABLED) &&
|
|
match)) {
|
|
if (filters->icmpv6_flags &
|
|
cpu_to_le32(SAP_ICMPV6_FILTER_COPY))
|
|
*rx_handler_res = RX_HANDLER_PASS;
|
|
else
|
|
*rx_handler_res = RX_HANDLER_CONSUMED;
|
|
|
|
return true;
|
|
}
|
|
break;
|
|
default:
|
|
return false;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
static bool iwl_mei_rx_filter_ipv6(struct sk_buff *skb,
|
|
const struct iwl_sap_oob_filters *filters,
|
|
rx_handler_result_t *rx_handler_res)
|
|
{
|
|
*rx_handler_res = RX_HANDLER_PASS;
|
|
|
|
/* TODO */
|
|
|
|
return false;
|
|
}
|
|
|
|
static rx_handler_result_t
|
|
iwl_mei_rx_pass_to_csme(struct sk_buff *skb,
|
|
const struct iwl_sap_oob_filters *filters,
|
|
bool *pass_to_csme)
|
|
{
|
|
const struct ethhdr *ethhdr = (void *)skb_mac_header(skb);
|
|
rx_handler_result_t rx_handler_res = RX_HANDLER_PASS;
|
|
bool (*filt_handler)(struct sk_buff *skb,
|
|
const struct iwl_sap_oob_filters *filters,
|
|
rx_handler_result_t *rx_handler_res);
|
|
|
|
/*
|
|
* skb->data points the IP header / ARP header and the ETH header
|
|
* is in the headroom.
|
|
*/
|
|
skb_reset_network_header(skb);
|
|
|
|
/*
|
|
* MCAST IP packets sent by us are received again here without
|
|
* an ETH header. Drop them here.
|
|
*/
|
|
if (!skb_mac_offset(skb))
|
|
return RX_HANDLER_PASS;
|
|
|
|
if (skb_headroom(skb) < sizeof(*ethhdr))
|
|
return RX_HANDLER_PASS;
|
|
|
|
if (iwl_mei_rx_filter_eth(ethhdr, filters,
|
|
pass_to_csme, &rx_handler_res))
|
|
return rx_handler_res;
|
|
|
|
switch (skb->protocol) {
|
|
case htons(ETH_P_IP):
|
|
filt_handler = iwl_mei_rx_filter_ipv4;
|
|
break;
|
|
case htons(ETH_P_ARP):
|
|
filt_handler = iwl_mei_rx_filter_arp;
|
|
break;
|
|
case htons(ETH_P_IPV6):
|
|
filt_handler = iwl_mei_rx_filter_ipv6;
|
|
break;
|
|
default:
|
|
*pass_to_csme = false;
|
|
return rx_handler_res;
|
|
}
|
|
|
|
*pass_to_csme = filt_handler(skb, filters, &rx_handler_res);
|
|
|
|
return rx_handler_res;
|
|
}
|
|
|
|
rx_handler_result_t iwl_mei_rx_filter(struct sk_buff *orig_skb,
|
|
const struct iwl_sap_oob_filters *filters,
|
|
bool *pass_to_csme)
|
|
{
|
|
rx_handler_result_t ret;
|
|
struct sk_buff *skb;
|
|
|
|
ret = iwl_mei_rx_pass_to_csme(orig_skb, filters, pass_to_csme);
|
|
|
|
if (!*pass_to_csme)
|
|
return RX_HANDLER_PASS;
|
|
|
|
if (ret == RX_HANDLER_PASS) {
|
|
skb = skb_copy(orig_skb, GFP_ATOMIC);
|
|
|
|
if (!skb)
|
|
return RX_HANDLER_PASS;
|
|
} else {
|
|
skb = orig_skb;
|
|
}
|
|
|
|
/* CSME wants the MAC header as well, push it back */
|
|
skb_push(skb, skb->data - skb_mac_header(skb));
|
|
|
|
/*
|
|
* Add the packet that CSME wants to get to the ring. Don't send the
|
|
* Check Shared Area HECI message since this is not possible from the
|
|
* Rx context. The caller will schedule a worker to do just that.
|
|
*/
|
|
iwl_mei_add_data_to_ring(skb, false);
|
|
|
|
/*
|
|
* In case we drop the packet, don't free it, the caller will do that
|
|
* for us
|
|
*/
|
|
if (ret == RX_HANDLER_PASS)
|
|
dev_kfree_skb(skb);
|
|
|
|
return ret;
|
|
}
|
|
|
|
#define DHCP_SERVER_PORT 67
|
|
#define DHCP_CLIENT_PORT 68
|
|
void iwl_mei_tx_copy_to_csme(struct sk_buff *origskb, unsigned int ivlen)
|
|
{
|
|
struct ieee80211_hdr *hdr;
|
|
struct sk_buff *skb;
|
|
struct ethhdr ethhdr;
|
|
struct ethhdr *eth;
|
|
|
|
/* Catch DHCP packets */
|
|
if (origskb->protocol != htons(ETH_P_IP) ||
|
|
ip_hdr(origskb)->protocol != IPPROTO_UDP ||
|
|
udp_hdr(origskb)->source != htons(DHCP_CLIENT_PORT) ||
|
|
udp_hdr(origskb)->dest != htons(DHCP_SERVER_PORT))
|
|
return;
|
|
|
|
/*
|
|
* We could be a bit less aggressive here and not copy everything, but
|
|
* this is very rare anyway, do don't bother much.
|
|
*/
|
|
skb = skb_copy(origskb, GFP_ATOMIC);
|
|
if (!skb)
|
|
return;
|
|
|
|
skb->protocol = origskb->protocol;
|
|
|
|
hdr = (void *)skb->data;
|
|
|
|
memcpy(ethhdr.h_dest, ieee80211_get_DA(hdr), ETH_ALEN);
|
|
memcpy(ethhdr.h_source, ieee80211_get_SA(hdr), ETH_ALEN);
|
|
|
|
/*
|
|
* Remove the ieee80211 header + IV + SNAP but leave the ethertype
|
|
* We still have enough headroom for the sap header.
|
|
*/
|
|
pskb_pull(skb, ieee80211_hdrlen(hdr->frame_control) + ivlen + 6);
|
|
eth = skb_push(skb, sizeof(ethhdr.h_dest) + sizeof(ethhdr.h_source));
|
|
memcpy(eth, ðhdr, sizeof(ethhdr.h_dest) + sizeof(ethhdr.h_source));
|
|
|
|
iwl_mei_add_data_to_ring(skb, true);
|
|
|
|
dev_kfree_skb(skb);
|
|
}
|
|
EXPORT_SYMBOL_GPL(iwl_mei_tx_copy_to_csme);
|