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>

1 files changed, 7 insertions, 6 deletions

diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c
index 352c26081f5d..8b9644a8b697 100644
--- a/net/ipv6/syncookies.c
+++ b/net/ipv6/syncookies.c
@@ -66,7 +66,7 @@ static inline struct sock *get_cookie_sock(struct sock *sk, struct sk_buff *skb,
 static DEFINE_PER_CPU(__u32 [16 + 5 + SHA_WORKSPACE_WORDS],
                       ipv6_cookie_scratch);
 
-static u32 cookie_hash(struct in6_addr *saddr, struct in6_addr *daddr,
+static u32 cookie_hash(const struct in6_addr *saddr, const struct in6_addr *daddr,
                        __be16 sport, __be16 dport, u32 count, int c)
 {
         __u32 *tmp = __get_cpu_var(ipv6_cookie_scratch);
@@ -86,7 +86,8 @@ static u32 cookie_hash(struct in6_addr *saddr, struct in6_addr *daddr,
         return tmp[17];
 }
 
-static __u32 secure_tcp_syn_cookie(struct in6_addr *saddr, struct in6_addr *daddr,
+static __u32 secure_tcp_syn_cookie(const struct in6_addr *saddr,
+                                   const struct in6_addr *daddr,
                                    __be16 sport, __be16 dport, __u32 sseq,
                                    __u32 count, __u32 data)
 {
@@ -96,8 +97,8 @@ static __u32 secure_tcp_syn_cookie(struct in6_addr *saddr, struct in6_addr *dadd
                 & COOKIEMASK));
 }
 
-static __u32 check_tcp_syn_cookie(__u32 cookie, struct in6_addr *saddr,
-                                  struct in6_addr *daddr, __be16 sport,
+static __u32 check_tcp_syn_cookie(__u32 cookie, const struct in6_addr *saddr,
+                                  const struct in6_addr *daddr, __be16 sport,
                                   __be16 dport, __u32 sseq, __u32 count,
                                   __u32 maxdiff)
 {
@@ -116,7 +117,7 @@ static __u32 check_tcp_syn_cookie(__u32 cookie, struct in6_addr *saddr,
 
 __u32 cookie_v6_init_sequence(struct sock *sk, struct sk_buff *skb, __u16 *mssp)
 {
-        struct ipv6hdr *iph = ipv6_hdr(skb);
+        const struct ipv6hdr *iph = ipv6_hdr(skb);
         const struct tcphdr *th = tcp_hdr(skb);
         int mssind;
         const __u16 mss = *mssp;
@@ -138,7 +139,7 @@ __u32 cookie_v6_init_sequence(struct sock *sk, struct sk_buff *skb, __u16 *mssp)
 
 static inline int cookie_check(struct sk_buff *skb, __u32 cookie)
 {
-        struct ipv6hdr *iph = ipv6_hdr(skb);
+        const struct ipv6hdr *iph = ipv6_hdr(skb);
         const struct tcphdr *th = tcp_hdr(skb);
         __u32 seq = ntohl(th->seq) - 1;
         __u32 mssind = check_tcp_syn_cookie(cookie, &iph->saddr, &iph->daddr,