inet: constify ip headers and in6_addr
Add const qualifiers to structs iphdr, ipv6hdr and in6_addr pointers
where possible, to make code intention more obvious.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index da5941f..24efd35 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -462,7 +462,7 @@
by themself???
*/
- struct iphdr *iph = (struct iphdr *)skb->data;
+ const struct iphdr *iph = (const struct iphdr *)skb->data;
__be16 *p = (__be16*)(skb->data+(iph->ihl<<2));
int grehlen = (iph->ihl<<2) + 4;
const int type = icmp_hdr(skb)->type;
@@ -534,7 +534,7 @@
rcu_read_unlock();
}
-static inline void ipgre_ecn_decapsulate(struct iphdr *iph, struct sk_buff *skb)
+static inline void ipgre_ecn_decapsulate(const struct iphdr *iph, struct sk_buff *skb)
{
if (INET_ECN_is_ce(iph->tos)) {
if (skb->protocol == htons(ETH_P_IP)) {
@@ -546,19 +546,19 @@
}
static inline u8
-ipgre_ecn_encapsulate(u8 tos, struct iphdr *old_iph, struct sk_buff *skb)
+ipgre_ecn_encapsulate(u8 tos, const struct iphdr *old_iph, struct sk_buff *skb)
{
u8 inner = 0;
if (skb->protocol == htons(ETH_P_IP))
inner = old_iph->tos;
else if (skb->protocol == htons(ETH_P_IPV6))
- inner = ipv6_get_dsfield((struct ipv6hdr *)old_iph);
+ inner = ipv6_get_dsfield((const struct ipv6hdr *)old_iph);
return INET_ECN_encapsulate(tos, inner);
}
static int ipgre_rcv(struct sk_buff *skb)
{
- struct iphdr *iph;
+ const struct iphdr *iph;
u8 *h;
__be16 flags;
__sum16 csum = 0;
@@ -697,8 +697,8 @@
{
struct ip_tunnel *tunnel = netdev_priv(dev);
struct pcpu_tstats *tstats;
- struct iphdr *old_iph = ip_hdr(skb);
- struct iphdr *tiph;
+ const struct iphdr *old_iph = ip_hdr(skb);
+ const struct iphdr *tiph;
u8 tos;
__be16 df;
struct rtable *rt; /* Route to the other host */
@@ -714,7 +714,7 @@
if (dev->header_ops && dev->type == ARPHRD_IPGRE) {
gre_hlen = 0;
- tiph = (struct iphdr *)skb->data;
+ tiph = (const struct iphdr *)skb->data;
} else {
gre_hlen = tunnel->hlen;
tiph = &tunnel->parms.iph;
@@ -735,14 +735,14 @@
}
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
else if (skb->protocol == htons(ETH_P_IPV6)) {
- struct in6_addr *addr6;
+ const struct in6_addr *addr6;
int addr_type;
struct neighbour *neigh = skb_dst(skb)->neighbour;
if (neigh == NULL)
goto tx_error;
- addr6 = (struct in6_addr *)&neigh->primary_key;
+ addr6 = (const struct in6_addr *)&neigh->primary_key;
addr_type = ipv6_addr_type(addr6);
if (addr_type == IPV6_ADDR_ANY) {
@@ -766,7 +766,7 @@
if (skb->protocol == htons(ETH_P_IP))
tos = old_iph->tos;
else if (skb->protocol == htons(ETH_P_IPV6))
- tos = ipv6_get_dsfield((struct ipv6hdr *)old_iph);
+ tos = ipv6_get_dsfield((const struct ipv6hdr *)old_iph);
}
rt = ip_route_output_gre(dev_net(dev), dst, tiph->saddr,
@@ -881,7 +881,7 @@
iph->ttl = old_iph->ttl;
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
else if (skb->protocol == htons(ETH_P_IPV6))
- iph->ttl = ((struct ipv6hdr *)old_iph)->hop_limit;
+ iph->ttl = ((const struct ipv6hdr *)old_iph)->hop_limit;
#endif
else
iph->ttl = ip4_dst_hoplimit(&rt->dst);
@@ -927,7 +927,7 @@
{
struct net_device *tdev = NULL;
struct ip_tunnel *tunnel;
- struct iphdr *iph;
+ const struct iphdr *iph;
int hlen = LL_MAX_HEADER;
int mtu = ETH_DATA_LEN;
int addend = sizeof(struct iphdr) + 4;
@@ -1180,7 +1180,7 @@
static int ipgre_header_parse(const struct sk_buff *skb, unsigned char *haddr)
{
- struct iphdr *iph = (struct iphdr *) skb_mac_header(skb);
+ const struct iphdr *iph = (const struct iphdr *) skb_mac_header(skb);
memcpy(haddr, &iph->saddr, 4);
return 4;
}