Merge branch 'listener_refactor_16'

Eric Dumazet says:

====================
tcp: listener refactor part 16

A CONFIG_PROVE_RCU=y build revealed an RCU splat I had to fix.

I added const qualifiers to various md5 methods, as I expect
to call them on behalf of request sock traffic even if
the listener socket is not locked. This seems ok, but adding
const makes the contract clearer. Note a good reduction
of code size thanks to request/establish sockets convergence.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller 2015-03-24 21:16:30 -04:00
commit b1275eb32e
5 changed files with 72 additions and 117 deletions

View File

@ -1296,15 +1296,14 @@ struct tcp_md5sig_pool {
};
/* - functions */
int tcp_v4_md5_hash_skb(char *md5_hash, struct tcp_md5sig_key *key,
const struct sock *sk, const struct request_sock *req,
const struct sk_buff *skb);
int tcp_v4_md5_hash_skb(char *md5_hash, const struct tcp_md5sig_key *key,
const struct sock *sk, const struct sk_buff *skb);
int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr,
int family, const u8 *newkey, u8 newkeylen, gfp_t gfp);
int tcp_md5_do_del(struct sock *sk, const union tcp_md5_addr *addr,
int family);
struct tcp_md5sig_key *tcp_v4_md5_lookup(struct sock *sk,
struct sock *addr_sk);
const struct sock *addr_sk);
#ifdef CONFIG_TCP_MD5SIG
struct tcp_md5sig_key *tcp_md5_do_lookup(struct sock *sk,
@ -1615,28 +1614,26 @@ int tcp_conn_request(struct request_sock_ops *rsk_ops,
struct tcp_sock_af_ops {
#ifdef CONFIG_TCP_MD5SIG
struct tcp_md5sig_key *(*md5_lookup) (struct sock *sk,
struct sock *addr_sk);
int (*calc_md5_hash) (char *location,
struct tcp_md5sig_key *md5,
const struct sock *sk,
const struct request_sock *req,
const struct sk_buff *skb);
int (*md5_parse) (struct sock *sk,
char __user *optval,
int optlen);
const struct sock *addr_sk);
int (*calc_md5_hash)(char *location,
const struct tcp_md5sig_key *md5,
const struct sock *sk,
const struct sk_buff *skb);
int (*md5_parse)(struct sock *sk,
char __user *optval,
int optlen);
#endif
};
struct tcp_request_sock_ops {
u16 mss_clamp;
#ifdef CONFIG_TCP_MD5SIG
struct tcp_md5sig_key *(*md5_lookup) (struct sock *sk,
struct request_sock *req);
int (*calc_md5_hash) (char *location,
struct tcp_md5sig_key *md5,
const struct sock *sk,
const struct request_sock *req,
const struct sk_buff *skb);
struct tcp_md5sig_key *(*req_md5_lookup)(struct sock *sk,
const struct sock *addr_sk);
int (*calc_md5_hash) (char *location,
const struct tcp_md5sig_key *md5,
const struct sock *sk,
const struct sk_buff *skb);
#endif
void (*init_req)(struct request_sock *req, struct sock *sk,
struct sk_buff *skb);

View File

@ -1913,18 +1913,19 @@ EXPORT_SYMBOL_GPL(tcp_set_state);
static const unsigned char new_state[16] = {
/* current state: new state: action: */
/* (Invalid) */ TCP_CLOSE,
/* TCP_ESTABLISHED */ TCP_FIN_WAIT1 | TCP_ACTION_FIN,
/* TCP_SYN_SENT */ TCP_CLOSE,
/* TCP_SYN_RECV */ TCP_FIN_WAIT1 | TCP_ACTION_FIN,
/* TCP_FIN_WAIT1 */ TCP_FIN_WAIT1,
/* TCP_FIN_WAIT2 */ TCP_FIN_WAIT2,
/* TCP_TIME_WAIT */ TCP_CLOSE,
/* TCP_CLOSE */ TCP_CLOSE,
/* TCP_CLOSE_WAIT */ TCP_LAST_ACK | TCP_ACTION_FIN,
/* TCP_LAST_ACK */ TCP_LAST_ACK,
/* TCP_LISTEN */ TCP_CLOSE,
/* TCP_CLOSING */ TCP_CLOSING,
[0 /* (Invalid) */] = TCP_CLOSE,
[TCP_ESTABLISHED] = TCP_FIN_WAIT1 | TCP_ACTION_FIN,
[TCP_SYN_SENT] = TCP_CLOSE,
[TCP_SYN_RECV] = TCP_FIN_WAIT1 | TCP_ACTION_FIN,
[TCP_FIN_WAIT1] = TCP_FIN_WAIT1,
[TCP_FIN_WAIT2] = TCP_FIN_WAIT2,
[TCP_TIME_WAIT] = TCP_CLOSE,
[TCP_CLOSE] = TCP_CLOSE,
[TCP_CLOSE_WAIT] = TCP_LAST_ACK | TCP_ACTION_FIN,
[TCP_LAST_ACK] = TCP_LAST_ACK,
[TCP_LISTEN] = TCP_CLOSE,
[TCP_CLOSING] = TCP_CLOSING,
[TCP_NEW_SYN_RECV] = TCP_CLOSE, /* should not happen ! */
};
static int tcp_close_state(struct sock *sk)

View File

@ -648,7 +648,7 @@ static void tcp_v4_send_reset(struct sock *sk, struct sk_buff *skb)
if (!key)
goto release_sk1;
genhash = tcp_v4_md5_hash_skb(newhash, key, NULL, NULL, skb);
genhash = tcp_v4_md5_hash_skb(newhash, key, NULL, skb);
if (genhash || memcmp(hash_location, newhash, 16) != 0)
goto release_sk1;
} else {
@ -898,10 +898,10 @@ struct tcp_md5sig_key *tcp_md5_do_lookup(struct sock *sk,
const union tcp_md5_addr *addr,
int family)
{
struct tcp_sock *tp = tcp_sk(sk);
const struct tcp_sock *tp = tcp_sk(sk);
struct tcp_md5sig_key *key;
unsigned int size = sizeof(struct in_addr);
struct tcp_md5sig_info *md5sig;
const struct tcp_md5sig_info *md5sig;
/* caller either holds rcu_read_lock() or socket lock */
md5sig = rcu_dereference_check(tp->md5sig_info,
@ -924,24 +924,15 @@ struct tcp_md5sig_key *tcp_md5_do_lookup(struct sock *sk,
EXPORT_SYMBOL(tcp_md5_do_lookup);
struct tcp_md5sig_key *tcp_v4_md5_lookup(struct sock *sk,
struct sock *addr_sk)
const struct sock *addr_sk)
{
union tcp_md5_addr *addr;
addr = (union tcp_md5_addr *)&inet_sk(addr_sk)->inet_daddr;
addr = (union tcp_md5_addr *)&sk->sk_daddr;
return tcp_md5_do_lookup(sk, addr, AF_INET);
}
EXPORT_SYMBOL(tcp_v4_md5_lookup);
static struct tcp_md5sig_key *tcp_v4_reqsk_md5_lookup(struct sock *sk,
struct request_sock *req)
{
union tcp_md5_addr *addr;
addr = (union tcp_md5_addr *)&inet_rsk(req)->ir_rmt_addr;
return tcp_md5_do_lookup(sk, addr, AF_INET);
}
/* This can be called on a newly created socket, from other files */
int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr,
int family, const u8 *newkey, u8 newkeylen, gfp_t gfp)
@ -1102,8 +1093,8 @@ clear_hash_noput:
return 1;
}
int tcp_v4_md5_hash_skb(char *md5_hash, struct tcp_md5sig_key *key,
const struct sock *sk, const struct request_sock *req,
int tcp_v4_md5_hash_skb(char *md5_hash, const struct tcp_md5sig_key *key,
const struct sock *sk,
const struct sk_buff *skb)
{
struct tcp_md5sig_pool *hp;
@ -1111,12 +1102,9 @@ int tcp_v4_md5_hash_skb(char *md5_hash, struct tcp_md5sig_key *key,
const struct tcphdr *th = tcp_hdr(skb);
__be32 saddr, daddr;
if (sk) {
saddr = inet_sk(sk)->inet_saddr;
daddr = inet_sk(sk)->inet_daddr;
} else if (req) {
saddr = inet_rsk(req)->ir_loc_addr;
daddr = inet_rsk(req)->ir_rmt_addr;
if (sk) { /* valid for establish/request sockets */
saddr = sk->sk_rcv_saddr;
daddr = sk->sk_daddr;
} else {
const struct iphdr *iph = ip_hdr(skb);
saddr = iph->saddr;
@ -1153,8 +1141,9 @@ clear_hash_noput:
}
EXPORT_SYMBOL(tcp_v4_md5_hash_skb);
static bool __tcp_v4_inbound_md5_hash(struct sock *sk,
const struct sk_buff *skb)
/* Called with rcu_read_lock() */
static bool tcp_v4_inbound_md5_hash(struct sock *sk,
const struct sk_buff *skb)
{
/*
* This gets called for each TCP segment that arrives
@ -1194,7 +1183,7 @@ static bool __tcp_v4_inbound_md5_hash(struct sock *sk,
*/
genhash = tcp_v4_md5_hash_skb(newhash,
hash_expected,
NULL, NULL, skb);
NULL, skb);
if (genhash || memcmp(hash_location, newhash, 16) != 0) {
net_info_ratelimited("MD5 Hash failed for (%pI4, %d)->(%pI4, %d)%s\n",
@ -1206,18 +1195,6 @@ static bool __tcp_v4_inbound_md5_hash(struct sock *sk,
}
return false;
}
static bool tcp_v4_inbound_md5_hash(struct sock *sk, const struct sk_buff *skb)
{
bool ret;
rcu_read_lock();
ret = __tcp_v4_inbound_md5_hash(sk, skb);
rcu_read_unlock();
return ret;
}
#endif
static void tcp_v4_init_req(struct request_sock *req, struct sock *sk_listener,
@ -1261,7 +1238,7 @@ struct request_sock_ops tcp_request_sock_ops __read_mostly = {
static const struct tcp_request_sock_ops tcp_request_sock_ipv4_ops = {
.mss_clamp = TCP_MSS_DEFAULT,
#ifdef CONFIG_TCP_MD5SIG
.md5_lookup = tcp_v4_reqsk_md5_lookup,
.req_md5_lookup = tcp_v4_md5_lookup,
.calc_md5_hash = tcp_v4_md5_hash_skb,
#endif
.init_req = tcp_v4_init_req,

View File

@ -601,15 +601,14 @@ static unsigned int tcp_synack_options(struct sock *sk,
struct request_sock *req,
unsigned int mss, struct sk_buff *skb,
struct tcp_out_options *opts,
struct tcp_md5sig_key **md5,
const struct tcp_md5sig_key *md5,
struct tcp_fastopen_cookie *foc)
{
struct inet_request_sock *ireq = inet_rsk(req);
unsigned int remaining = MAX_TCP_OPTION_SPACE;
#ifdef CONFIG_TCP_MD5SIG
*md5 = tcp_rsk(req)->af_specific->md5_lookup(sk, req);
if (*md5) {
if (md5) {
opts->options |= OPTION_MD5;
remaining -= TCPOLEN_MD5SIG_ALIGNED;
@ -620,8 +619,6 @@ static unsigned int tcp_synack_options(struct sock *sk,
*/
ireq->tstamp_ok &= !ireq->sack_ok;
}
#else
*md5 = NULL;
#endif
/* We always send an MSS option. */
@ -989,7 +986,7 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
if (md5) {
sk_nocaps_add(sk, NETIF_F_GSO_MASK);
tp->af_specific->calc_md5_hash(opts.hash_location,
md5, sk, NULL, skb);
md5, sk, skb);
}
#endif
@ -2913,7 +2910,7 @@ struct sk_buff *tcp_make_synack(struct sock *sk, struct dst_entry *dst,
struct tcp_sock *tp = tcp_sk(sk);
struct tcphdr *th;
struct sk_buff *skb;
struct tcp_md5sig_key *md5;
struct tcp_md5sig_key *md5 = NULL;
int tcp_header_size;
int mss;
@ -2938,7 +2935,12 @@ struct sk_buff *tcp_make_synack(struct sock *sk, struct dst_entry *dst,
else
#endif
skb_mstamp_get(&skb->skb_mstamp);
tcp_header_size = tcp_synack_options(sk, req, mss, skb, &opts, &md5,
#ifdef CONFIG_TCP_MD5SIG
rcu_read_lock();
md5 = tcp_rsk(req)->af_specific->req_md5_lookup(sk, req_to_sk(req));
#endif
tcp_header_size = tcp_synack_options(sk, req, mss, skb, &opts, md5,
foc) + sizeof(*th);
skb_push(skb, tcp_header_size);
@ -2969,10 +2971,10 @@ struct sk_buff *tcp_make_synack(struct sock *sk, struct dst_entry *dst,
#ifdef CONFIG_TCP_MD5SIG
/* Okay, we have all we need - do the md5 hash if needed */
if (md5) {
if (md5)
tcp_rsk(req)->af_specific->calc_md5_hash(opts.hash_location,
md5, NULL, req, skb);
}
md5, req_to_sk(req), skb);
rcu_read_unlock();
#endif
return skb;

View File

@ -486,17 +486,11 @@ static struct tcp_md5sig_key *tcp_v6_md5_do_lookup(struct sock *sk,
}
static struct tcp_md5sig_key *tcp_v6_md5_lookup(struct sock *sk,
struct sock *addr_sk)
const struct sock *addr_sk)
{
return tcp_v6_md5_do_lookup(sk, &addr_sk->sk_v6_daddr);
}
static struct tcp_md5sig_key *tcp_v6_reqsk_md5_lookup(struct sock *sk,
struct request_sock *req)
{
return tcp_v6_md5_do_lookup(sk, &inet_rsk(req)->ir_v6_rmt_addr);
}
static int tcp_v6_parse_md5_keys(struct sock *sk, char __user *optval,
int optlen)
{
@ -582,9 +576,9 @@ clear_hash_noput:
return 1;
}
static int tcp_v6_md5_hash_skb(char *md5_hash, struct tcp_md5sig_key *key,
static int tcp_v6_md5_hash_skb(char *md5_hash,
const struct tcp_md5sig_key *key,
const struct sock *sk,
const struct request_sock *req,
const struct sk_buff *skb)
{
const struct in6_addr *saddr, *daddr;
@ -592,12 +586,9 @@ static int tcp_v6_md5_hash_skb(char *md5_hash, struct tcp_md5sig_key *key,
struct hash_desc *desc;
const struct tcphdr *th = tcp_hdr(skb);
if (sk) {
saddr = &inet6_sk(sk)->saddr;
if (sk) { /* valid for establish/request sockets */
saddr = &sk->sk_v6_rcv_saddr;
daddr = &sk->sk_v6_daddr;
} else if (req) {
saddr = &inet_rsk(req)->ir_v6_loc_addr;
daddr = &inet_rsk(req)->ir_v6_rmt_addr;
} else {
const struct ipv6hdr *ip6h = ipv6_hdr(skb);
saddr = &ip6h->saddr;
@ -633,8 +624,7 @@ clear_hash_noput:
return 1;
}
static int __tcp_v6_inbound_md5_hash(struct sock *sk,
const struct sk_buff *skb)
static bool tcp_v6_inbound_md5_hash(struct sock *sk, const struct sk_buff *skb)
{
const __u8 *hash_location = NULL;
struct tcp_md5sig_key *hash_expected;
@ -648,44 +638,32 @@ static int __tcp_v6_inbound_md5_hash(struct sock *sk,
/* We've parsed the options - do we have a hash? */
if (!hash_expected && !hash_location)
return 0;
return false;
if (hash_expected && !hash_location) {
NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND);
return 1;
return true;
}
if (!hash_expected && hash_location) {
NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED);
return 1;
return true;
}
/* check the signature */
genhash = tcp_v6_md5_hash_skb(newhash,
hash_expected,
NULL, NULL, skb);
NULL, skb);
if (genhash || memcmp(hash_location, newhash, 16) != 0) {
net_info_ratelimited("MD5 Hash %s for [%pI6c]:%u->[%pI6c]:%u\n",
genhash ? "failed" : "mismatch",
&ip6h->saddr, ntohs(th->source),
&ip6h->daddr, ntohs(th->dest));
return 1;
return true;
}
return 0;
return false;
}
static int tcp_v6_inbound_md5_hash(struct sock *sk, const struct sk_buff *skb)
{
int ret;
rcu_read_lock();
ret = __tcp_v6_inbound_md5_hash(sk, skb);
rcu_read_unlock();
return ret;
}
#endif
static void tcp_v6_init_req(struct request_sock *req, struct sock *sk,
@ -736,7 +714,7 @@ static const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = {
.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) -
sizeof(struct ipv6hdr),
#ifdef CONFIG_TCP_MD5SIG
.md5_lookup = tcp_v6_reqsk_md5_lookup,
.req_md5_lookup = tcp_v6_md5_lookup,
.calc_md5_hash = tcp_v6_md5_hash_skb,
#endif
.init_req = tcp_v6_init_req,
@ -893,7 +871,7 @@ static void tcp_v6_send_reset(struct sock *sk, struct sk_buff *skb)
if (!key)
goto release_sk1;
genhash = tcp_v6_md5_hash_skb(newhash, key, NULL, NULL, skb);
genhash = tcp_v6_md5_hash_skb(newhash, key, NULL, skb);
if (genhash || memcmp(hash_location, newhash, 16) != 0)
goto release_sk1;
} else {