/* Azure hosts don't support non-TCP port numbers in hashing yet. We compute
* hash for non-TCP traffic with only IP numbers.
*/
static inline u32 netvsc_get_hash(struct sk_buff *skb, struct sock *sk)
{
struct flow_keys flow;
u32 hash;
static u32 hashrnd __read_mostly;
net_get_random_once(&hashrnd, sizeof(hashrnd));
if (!skb_flow_dissect_flow_keys(skb, &flow, 0))
return 0;
if (flow.basic.ip_proto == IPPROTO_TCP) {
return skb_get_hash(skb);
} else {
if (flow.basic.n_proto == htons(ETH_P_IP))
hash = jhash2((u32 *)&flow.addrs.v4addrs, 2, hashrnd);
else if (flow.basic.n_proto == htons(ETH_P_IPV6))
hash = jhash2((u32 *)&flow.addrs.v6addrs, 8, hashrnd);
else
hash = 0;
skb_set_hash(skb, hash, PKT_HASH_TYPE_L3);
}
return hash;
}
static unsigned int ipqhashfn(__be16 id, __be32 saddr, __be32 daddr, u8 prot)
{
net_get_random_once(&ip4_frags.rnd, sizeof(ip4_frags.rnd));
return jhash_3words((__force u32)id << 16 | prot,
(__force u32)saddr, (__force u32)daddr,
ip4_frags.rnd);
}
/*
* callers should be careful not to use the hash value outside the ipfrag_lock
* as doing so could race with ipfrag_hash_rnd being recalculated.
*/
static unsigned int inet6_hash_frag(__be32 id, const struct in6_addr *saddr,
const struct in6_addr *daddr)
{
net_get_random_once(&ip6_frags.rnd, sizeof(ip6_frags.rnd));
return jhash_3words(ipv6_addr_hash(saddr), ipv6_addr_hash(daddr),
(__force u32)id, ip6_frags.rnd);
}
static u32 cookie_hash(__be32 saddr, __be32 daddr, __be16 sport, __be16 dport,
u32 count, int c)
{
net_get_random_once(syncookie_secret, sizeof(syncookie_secret));
return siphash_4u32((__force u32)saddr, (__force u32)daddr,
(__force u32)sport << 16 | (__force u32)dport,
count, &syncookie_secret[c]);
}
static unsigned int lowpan_hash_frag(__be16 tag, u16 d_size,
const struct ieee802154_addr *saddr,
const struct ieee802154_addr *daddr)
{
net_get_random_once(&lowpan_frags.rnd, sizeof(lowpan_frags.rnd));
return jhash_3words(ieee802154_addr_hash(saddr),
ieee802154_addr_hash(daddr),
(__force u32)(tag + (d_size << 16)),
lowpan_frags.rnd);
}
void tcp_fastopen_init_key_once(bool publish)
{
static u8 key[TCP_FASTOPEN_KEY_LENGTH];
/* tcp_fastopen_reset_cipher publishes the new context
* atomically, so we allow this race happening here.
*
* All call sites of tcp_fastopen_cookie_gen also check
* for a valid cookie, so this is an acceptable risk.
*/
if (net_get_random_once(key, sizeof(key)) && publish)
tcp_fastopen_reset_cipher(key, sizeof(key));
}
static void ipv6_select_ident(struct frag_hdr *fhdr, struct rt6_info *rt)
{
static u32 ip6_idents_hashrnd __read_mostly;
u32 hash, id;
net_get_random_once(&ip6_idents_hashrnd, sizeof(ip6_idents_hashrnd));
hash = __ipv6_addr_jhash(&rt->rt6i_dst.addr, ip6_idents_hashrnd);
hash = __ipv6_addr_jhash(&rt->rt6i_src.addr, hash);
id = ip_idents_reserve(hash, 1);
fhdr->identification = htonl(id);
}
/* returns -ve errno or +ve port */
static int rds_add_bound(struct rds_sock *rs, __be32 addr, __be16 *port)
{
int ret = -EADDRINUSE;
u16 rover, last;
u64 key;
if (*port != 0) {
rover = be16_to_cpu(*port);
if (rover == RDS_FLAG_PROBE_PORT)
return -EINVAL;
last = rover;
} else {
rover = max_t(u16, prandom_u32(), 2);
last = rover - 1;
}
do {
if (rover == 0)
rover++;
if (rover == RDS_FLAG_PROBE_PORT)
continue;
key = ((u64)addr << 32) | cpu_to_be16(rover);
if (rhashtable_lookup_fast(&bind_hash_table, &key, ht_parms))
continue;
rs->rs_bound_key = key;
rs->rs_bound_addr = addr;
net_get_random_once(&rs->rs_hash_initval,
sizeof(rs->rs_hash_initval));
rs->rs_bound_port = cpu_to_be16(rover);
rs->rs_bound_node.next = NULL;
rds_sock_addref(rs);
if (!rhashtable_insert_fast(&bind_hash_table,
&rs->rs_bound_node, ht_parms)) {
*port = rs->rs_bound_port;
ret = 0;
rdsdebug("rs %p binding to %pI4:%d\n",
rs, &addr, (int)ntohs(*port));
break;
} else {
rds_sock_put(rs);
ret = -ENOMEM;
break;
}
} while (rover++ != last);
return ret;
}
static u32 cookie_hash(__be32 saddr, __be32 daddr, __be16 sport, __be16 dport,
u32 count, int c)
{
__u32 *tmp;
net_get_random_once(syncookie_secret, sizeof(syncookie_secret));
tmp = this_cpu_ptr(ipv4_cookie_scratch);
memcpy(tmp + 4, syncookie_secret[c], sizeof(syncookie_secret[c]));
tmp[0] = (__force u32)saddr;
tmp[1] = (__force u32)daddr;
tmp[2] = ((__force u32)sport << 16) + (__force u32)dport;
tmp[3] = count;
sha_transform(tmp + 16, (__u8 *)tmp, tmp + 16 + 5);
return tmp[17];
}
static __always_inline void __flow_hash_secret_init(void)
{
net_get_random_once(&hashrnd, sizeof(hashrnd));
}
static __always_inline void net_secret_init(void)
{
net_get_random_once(net_secret, sizeof(net_secret));
}
