*
* Implementation of the Transmission Control Protocol(TCP).
*
- * Version: $Id: tcp_ipv4.c,v 1.240 2002/02/01 22:01:04 davem Exp $
- *
* IPv4 specific functions
*
*
__be32 addr);
static int tcp_v4_do_calc_md5_hash(char *md5_hash, struct tcp_md5sig_key *key,
__be32 saddr, __be32 daddr,
- struct tcphdr *th, int protocol,
- unsigned int tcplen);
+ struct tcphdr *th, unsigned int tcplen);
+#else
+static inline
+struct tcp_md5sig_key *tcp_v4_md5_do_lookup(struct sock *sk, __be32 addr)
+{
+ return NULL;
+}
#endif
struct inet_hashinfo __cacheline_aligned tcp_hashinfo = {
key,
ip_hdr(skb)->daddr,
ip_hdr(skb)->saddr,
- &rep.th, IPPROTO_TCP,
- arg.iov[0].iov_len);
+ &rep.th, arg.iov[0].iov_len);
}
#endif
arg.csum = csum_tcpudp_nofold(ip_hdr(skb)->daddr,
outside socket context is ugly, certainly. What can I do?
*/
-static void tcp_v4_send_ack(struct tcp_timewait_sock *twsk,
- struct sk_buff *skb, u32 seq, u32 ack,
- u32 win, u32 ts)
+static void tcp_v4_send_ack(struct sk_buff *skb, u32 seq, u32 ack,
+ u32 win, u32 ts, int oif,
+ struct tcp_md5sig_key *key)
{
struct tcphdr *th = tcp_hdr(skb);
struct {
];
} rep;
struct ip_reply_arg arg;
-#ifdef CONFIG_TCP_MD5SIG
- struct tcp_md5sig_key *key;
- struct tcp_md5sig_key tw_key;
-#endif
memset(&rep.th, 0, sizeof(struct tcphdr));
memset(&arg, 0, sizeof(arg));
rep.th.window = htons(win);
#ifdef CONFIG_TCP_MD5SIG
- /*
- * The SKB holds an imcoming packet, but may not have a valid ->sk
- * pointer. This is especially the case when we're dealing with a
- * TIME_WAIT ack, because the sk structure is long gone, and only
- * the tcp_timewait_sock remains. So the md5 key is stashed in that
- * structure, and we use it in preference. I believe that (twsk ||
- * skb->sk) holds true, but we program defensively.
- */
- if (!twsk && skb->sk) {
- key = tcp_v4_md5_do_lookup(skb->sk, ip_hdr(skb)->daddr);
- } else if (twsk && twsk->tw_md5_keylen) {
- tw_key.key = twsk->tw_md5_key;
- tw_key.keylen = twsk->tw_md5_keylen;
- key = &tw_key;
- } else
- key = NULL;
-
if (key) {
int offset = (ts) ? 3 : 0;
key,
ip_hdr(skb)->daddr,
ip_hdr(skb)->saddr,
- &rep.th, IPPROTO_TCP,
- arg.iov[0].iov_len);
+ &rep.th, arg.iov[0].iov_len);
}
#endif
arg.csum = csum_tcpudp_nofold(ip_hdr(skb)->daddr,
ip_hdr(skb)->saddr, /* XXX */
arg.iov[0].iov_len, IPPROTO_TCP, 0);
arg.csumoffset = offsetof(struct tcphdr, check) / 2;
- if (twsk)
- arg.bound_dev_if = twsk->tw_sk.tw_bound_dev_if;
+ if (oif)
+ arg.bound_dev_if = oif;
ip_send_reply(dev_net(skb->dev)->ipv4.tcp_sock, skb,
&arg, arg.iov[0].iov_len);
struct inet_timewait_sock *tw = inet_twsk(sk);
struct tcp_timewait_sock *tcptw = tcp_twsk(sk);
- tcp_v4_send_ack(tcptw, skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt,
+ tcp_v4_send_ack(skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt,
tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale,
- tcptw->tw_ts_recent);
+ tcptw->tw_ts_recent,
+ tw->tw_bound_dev_if,
+ tcp_twsk_md5_key(tcptw)
+ );
inet_twsk_put(tw);
}
static void tcp_v4_reqsk_send_ack(struct sk_buff *skb,
struct request_sock *req)
{
- tcp_v4_send_ack(NULL, skb, tcp_rsk(req)->snt_isn + 1,
+ tcp_v4_send_ack(skb, tcp_rsk(req)->snt_isn + 1,
tcp_rsk(req)->rcv_isn + 1, req->rcv_wnd,
- req->ts_recent);
+ req->ts_recent,
+ 0,
+ tcp_v4_md5_do_lookup(skb->sk, ip_hdr(skb)->daddr));
}
/*
static int tcp_v4_do_calc_md5_hash(char *md5_hash, struct tcp_md5sig_key *key,
__be32 saddr, __be32 daddr,
- struct tcphdr *th, int protocol,
+ struct tcphdr *th,
unsigned int tcplen)
{
- struct scatterlist sg[4];
- __u16 data_len;
- int block = 0;
- __sum16 old_checksum;
struct tcp_md5sig_pool *hp;
struct tcp4_pseudohdr *bp;
- struct hash_desc *desc;
int err;
- unsigned int nbytes = 0;
/*
* Okay, so RFC2385 is turned on for this connection,
goto clear_hash_noput;
bp = &hp->md5_blk.ip4;
- desc = &hp->md5_desc;
/*
- * 1. the TCP pseudo-header (in the order: source IP address,
+ * The TCP pseudo-header (in the order: source IP address,
* destination IP address, zero-padded protocol number, and
* segment length)
*/
bp->saddr = saddr;
bp->daddr = daddr;
bp->pad = 0;
- bp->protocol = protocol;
+ bp->protocol = IPPROTO_TCP;
bp->len = htons(tcplen);
- sg_init_table(sg, 4);
-
- sg_set_buf(&sg[block++], bp, sizeof(*bp));
- nbytes += sizeof(*bp);
-
- /* 2. the TCP header, excluding options, and assuming a
- * checksum of zero/
- */
- old_checksum = th->check;
- th->check = 0;
- sg_set_buf(&sg[block++], th, sizeof(struct tcphdr));
- nbytes += sizeof(struct tcphdr);
-
- /* 3. the TCP segment data (if any) */
- data_len = tcplen - (th->doff << 2);
- if (data_len > 0) {
- unsigned char *data = (unsigned char *)th + (th->doff << 2);
- sg_set_buf(&sg[block++], data, data_len);
- nbytes += data_len;
- }
-
- /* 4. an independently-specified key or password, known to both
- * TCPs and presumably connection-specific
- */
- sg_set_buf(&sg[block++], key->key, key->keylen);
- nbytes += key->keylen;
-
- sg_mark_end(&sg[block - 1]);
-
- /* Now store the Hash into the packet */
- err = crypto_hash_init(desc);
- if (err)
- goto clear_hash;
- err = crypto_hash_update(desc, sg, nbytes);
- if (err)
- goto clear_hash;
- err = crypto_hash_final(desc, md5_hash);
+ err = tcp_calc_md5_hash(md5_hash, key, sizeof(*bp),
+ th, tcplen, hp);
if (err)
goto clear_hash;
- /* Reset header, and free up the crypto */
+ /* Free up the crypto pool */
tcp_put_md5sig_pool();
- th->check = old_checksum;
-
out:
return 0;
clear_hash:
struct sock *sk,
struct dst_entry *dst,
struct request_sock *req,
- struct tcphdr *th, int protocol,
+ struct tcphdr *th,
unsigned int tcplen)
{
__be32 saddr, daddr;
}
return tcp_v4_do_calc_md5_hash(md5_hash, key,
saddr, daddr,
- th, protocol, tcplen);
+ th, tcplen);
}
EXPORT_SYMBOL(tcp_v4_calc_md5_hash);
struct tcp_md5sig_key *hash_expected;
const struct iphdr *iph = ip_hdr(skb);
struct tcphdr *th = tcp_hdr(skb);
- int length = (th->doff << 2) - sizeof(struct tcphdr);
int genhash;
- unsigned char *ptr;
unsigned char newhash[16];
hash_expected = tcp_v4_md5_do_lookup(sk, iph->saddr);
+ hash_location = tcp_parse_md5sig_option(th);
- /*
- * If the TCP option length is less than the TCP_MD5SIG
- * option length, then we can shortcut
- */
- if (length < TCPOLEN_MD5SIG) {
- if (hash_expected)
- return 1;
- else
- return 0;
- }
-
- /* Okay, we can't shortcut - we have to grub through the options */
- ptr = (unsigned char *)(th + 1);
- while (length > 0) {
- int opcode = *ptr++;
- int opsize;
-
- switch (opcode) {
- case TCPOPT_EOL:
- goto done_opts;
- case TCPOPT_NOP:
- length--;
- continue;
- default:
- opsize = *ptr++;
- if (opsize < 2)
- goto done_opts;
- if (opsize > length)
- goto done_opts;
-
- if (opcode == TCPOPT_MD5SIG) {
- hash_location = ptr;
- goto done_opts;
- }
- }
- ptr += opsize-2;
- length -= opsize;
- }
-done_opts:
/* We've parsed the options - do we have a hash? */
if (!hash_expected && !hash_location)
return 0;
genhash = tcp_v4_do_calc_md5_hash(newhash,
hash_expected,
iph->saddr, iph->daddr,
- th, sk->sk_protocol,
- skb->len);
+ th, skb->len);
if (genhash || memcmp(hash_location, newhash, 16) != 0) {
if (net_ratelimit()) {
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff