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WSL2-Linux-Kernel
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[TCP]: MD5 Signature Option (RFC2385) support. 

Based on implementation by Rick Payne.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
YOSHIFUJI Hideaki 2006-11-14 19:07:45 -08:00 коммит произвёл David S. Miller
Родитель bf6bce71ea
Коммит cfb6eeb4c8
15 изменённых файлов: 1714 добавлений и 64 удалений
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3
CREDITS
Просмотреть файл

@ -2598,6 +2598,9 @@ S: Ucitelska 1576
S: Prague 8
S: 182 00 Czech Republic
N: Rick Payne
D: RFC2385 Support for TCP
N: Barak A. Pearlmutter
E: bap@cs.unm.edu
W: http://www.cs.unm.edu/~bap/

35
include/linux/tcp.h
Просмотреть файл

@ -19,6 +19,7 @@
#include <linux/types.h>
#include <asm/byteorder.h>
#include <linux/socket.h>
struct tcphdr {
__be16 source;
@ -94,6 +95,7 @@ enum {
#define TCP_INFO 11 /* Information about this connection. */
#define TCP_QUICKACK 12 /* Block/reenable quick acks */
#define TCP_CONGESTION 13 /* Congestion control algorithm */
#define TCP_MD5SIG 14 /* TCP MD5 Signature (RFC2385) */
#define TCPI_OPT_TIMESTAMPS 1
#define TCPI_OPT_SACK 2
@ -157,6 +159,17 @@ struct tcp_info
__u32 tcpi_total_retrans;
};
/* for TCP_MD5SIG socket option */
#define TCP_MD5SIG_MAXKEYLEN 80
struct tcp_md5sig {
struct __kernel_sockaddr_storage tcpm_addr; /* address associated */
__u16 __tcpm_pad1; /* zero */
__u16 tcpm_keylen; /* key length */
__u32 __tcpm_pad2; /* zero */
__u8 tcpm_key[TCP_MD5SIG_MAXKEYLEN]; /* key (binary) */
};
#ifdef __KERNEL__
#include <linux/skbuff.h>
@ -197,9 +210,13 @@ struct tcp_options_received {
};
struct tcp_request_sock {
struct inet_request_sock req;
__u32 rcv_isn;
__u32 snt_isn;
struct inet_request_sock req;
#ifdef CONFIG_TCP_MD5SIG
/* Only used by TCP MD5 Signature so far. */
struct tcp_request_sock_ops *af_specific;
#endif
__u32 rcv_isn;
__u32 snt_isn;
};
static inline struct tcp_request_sock *tcp_rsk(const struct request_sock *req)
@ -363,6 +380,14 @@ struct tcp_sock {
__u32 probe_seq_start;
__u32 probe_seq_end;
} mtu_probe;
#ifdef CONFIG_TCP_MD5SIG
/* TCP AF-Specific parts; only used by MD5 Signature support so far */
struct tcp_sock_af_ops *af_specific;
/* TCP MD5 Signagure Option information */
struct tcp_md5sig_info *md5sig_info;
#endif
};
static inline struct tcp_sock *tcp_sk(const struct sock *sk)
@ -377,6 +402,10 @@ struct tcp_timewait_sock {
__u32 tw_rcv_wnd;
__u32 tw_ts_recent;
long tw_ts_recent_stamp;
#ifdef CONFIG_TCP_MD5SIG
__u16 tw_md5_keylen;
__u8 tw_md5_key[TCP_MD5SIG_MAXKEYLEN];
#endif
};
static inline struct tcp_timewait_sock *tcp_twsk(const struct sock *sk)

3
include/net/request_sock.h
Просмотреть файл

@ -35,7 +35,8 @@ struct request_sock_ops {
struct dst_entry *dst);
void (*send_ack)(struct sk_buff *skb,
struct request_sock *req);
void (*send_reset)(struct sk_buff *skb);
void (*send_reset)(struct sock *sk,
struct sk_buff *skb);
void (*destructor)(struct request_sock *req);
};

143
include/net/tcp.h
Просмотреть файл

@ -28,6 +28,7 @@
#include <linux/percpu.h>
#include <linux/skbuff.h>
#include <linux/dmaengine.h>
#include <linux/crypto.h>
#include <net/inet_connection_sock.h>
#include <net/inet_timewait_sock.h>
@ -161,6 +162,7 @@ extern void tcp_time_wait(struct sock *sk, int state, int timeo);
#define TCPOPT_SACK_PERM 4 /* SACK Permitted */
#define TCPOPT_SACK 5 /* SACK Block */
#define TCPOPT_TIMESTAMP 8 /* Better RTT estimations/PAWS */
#define TCPOPT_MD5SIG 19 /* MD5 Signature (RFC2385) */
/*
* TCP option lengths
@ -170,6 +172,7 @@ extern void tcp_time_wait(struct sock *sk, int state, int timeo);
#define TCPOLEN_WINDOW 3
#define TCPOLEN_SACK_PERM 2
#define TCPOLEN_TIMESTAMP 10
#define TCPOLEN_MD5SIG 18
/* But this is what stacks really send out. */
#define TCPOLEN_TSTAMP_ALIGNED 12
@ -178,6 +181,7 @@ extern void tcp_time_wait(struct sock *sk, int state, int timeo);
#define TCPOLEN_SACK_BASE 2
#define TCPOLEN_SACK_BASE_ALIGNED 4
#define TCPOLEN_SACK_PERBLOCK 8
#define TCPOLEN_MD5SIG_ALIGNED 20
/* Flags in tp->nonagle */
#define TCP_NAGLE_OFF 1 /* Nagle's algo is disabled */
@ -299,6 +303,8 @@ extern void tcp_cleanup_rbuf(struct sock *sk, int copied);
extern int tcp_twsk_unique(struct sock *sk,
struct sock *sktw, void *twp);
extern void tcp_twsk_destructor(struct sock *sk);
static inline void tcp_dec_quickack_mode(struct sock *sk,
const unsigned int pkts)
{
@ -1064,6 +1070,114 @@ static inline void clear_all_retrans_hints(struct tcp_sock *tp){
tp->fastpath_skb_hint = NULL;
}
/* MD5 Signature */
struct crypto_hash;
/* - key database */
struct tcp_md5sig_key {
u8 *key;
u8 keylen;
};
struct tcp4_md5sig_key {
u8 *key;
u16 keylen;
__be32 addr;
};
struct tcp6_md5sig_key {
u8 *key;
u16 keylen;
#if 0
u32 scope_id; /* XXX */
#endif
struct in6_addr addr;
};
/* - sock block */
struct tcp_md5sig_info {
struct tcp4_md5sig_key *keys4;
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
struct tcp6_md5sig_key *keys6;
u32 entries6;
u32 alloced6;
#endif
u32 entries4;
u32 alloced4;
};
/* - pseudo header */
struct tcp4_pseudohdr {
__be32 saddr;
__be32 daddr;
__u8 pad;
__u8 protocol;
__be16 len;
};
struct tcp6_pseudohdr {
struct in6_addr saddr;
struct in6_addr daddr;
__be32 len;
__be32 protocol; /* including padding */
};
union tcp_md5sum_block {
struct tcp4_pseudohdr ip4;
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
struct tcp6_pseudohdr ip6;
#endif
};
/* - pool: digest algorithm, hash description and scratch buffer */
struct tcp_md5sig_pool {
struct hash_desc md5_desc;
union tcp_md5sum_block md5_blk;
};
#define TCP_MD5SIG_MAXKEYS (~(u32)0) /* really?! */
/* - functions */
extern int tcp_v4_calc_md5_hash(char *md5_hash,
struct tcp_md5sig_key *key,
struct sock *sk,
struct dst_entry *dst,
struct request_sock *req,
struct tcphdr *th,
int protocol, int tcplen);
extern struct tcp_md5sig_key *tcp_v4_md5_lookup(struct sock *sk,
struct sock *addr_sk);
extern int tcp_v4_md5_do_add(struct sock *sk,
__be32 addr,
u8 *newkey,
u8 newkeylen);
extern int tcp_v4_md5_do_del(struct sock *sk,
u32 addr);
extern struct tcp_md5sig_pool **tcp_alloc_md5sig_pool(void);
extern void tcp_free_md5sig_pool(void);
extern struct tcp_md5sig_pool *__tcp_get_md5sig_pool(int cpu);
extern void __tcp_put_md5sig_pool(void);
static inline
struct tcp_md5sig_pool *tcp_get_md5sig_pool(void)
{
int cpu = get_cpu();
struct tcp_md5sig_pool *ret = __tcp_get_md5sig_pool(cpu);
if (!ret)
put_cpu();
return ret;
}
static inline void tcp_put_md5sig_pool(void)
{
__tcp_put_md5sig_pool();
put_cpu();
}
/* /proc */
enum tcp_seq_states {
TCP_SEQ_STATE_LISTENING,
@ -1103,6 +1217,35 @@ extern int tcp4_proc_init(void);
extern void tcp4_proc_exit(void);
#endif
/* TCP af-specific functions */
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,
struct sock *sk,
struct dst_entry *dst,
struct request_sock *req,
struct tcphdr *th,
int protocol, int len);
int (*md5_add) (struct sock *sk,
struct sock *addr_sk,
u8 *newkey,
u8 len);
int (*md5_parse) (struct sock *sk,
char __user *optval,
int optlen);
#endif
};
struct tcp_request_sock_ops {
#ifdef CONFIG_TCP_MD5SIG
struct tcp_md5sig_key *(*md5_lookup) (struct sock *sk,
struct request_sock *req);
#endif
};
extern void tcp_v4_init(struct net_proto_family *ops);
extern void tcp_init(void);

3
include/net/timewait_sock.h
Просмотреть файл

@ -31,6 +31,9 @@ static inline int twsk_unique(struct sock *sk, struct sock *sktw, void *twp)
static inline void twsk_destructor(struct sock *sk)
{
BUG_ON(sk == NULL);
BUG_ON(sk->sk_prot == NULL);
BUG_ON(sk->sk_prot->twsk_prot == NULL);
if (sk->sk_prot->twsk_prot->twsk_destructor != NULL)
sk->sk_prot->twsk_prot->twsk_destructor(sk);
}

6
net/dccp/ipv4.c
Просмотреть файл

@ -509,7 +509,7 @@ out:
return err;
}
static void dccp_v4_ctl_send_reset(struct sk_buff *rxskb)
static void dccp_v4_ctl_send_reset(struct sock *sk, struct sk_buff *rxskb)
{
int err;
struct dccp_hdr *rxdh = dccp_hdr(rxskb), *dh;
@ -724,7 +724,7 @@ int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
return 0;
reset:
dccp_v4_ctl_send_reset(skb);
dccp_v4_ctl_send_reset(sk, skb);
discard:
kfree_skb(skb);
return 0;
@ -913,7 +913,7 @@ no_dccp_socket:
if (dh->dccph_type != DCCP_PKT_RESET) {
DCCP_SKB_CB(skb)->dccpd_reset_code =
DCCP_RESET_CODE_NO_CONNECTION;
dccp_v4_ctl_send_reset(skb);
dccp_v4_ctl_send_reset(sk, skb);
}
discard_it:

6
net/dccp/ipv6.c
Просмотреть файл

@ -310,7 +310,7 @@ static void dccp_v6_reqsk_destructor(struct request_sock *req)
kfree_skb(inet6_rsk(req)->pktopts);
}
static void dccp_v6_ctl_send_reset(struct sk_buff *rxskb)
static void dccp_v6_ctl_send_reset(struct sock *sk, struct sk_buff *rxskb)
{
struct dccp_hdr *rxdh = dccp_hdr(rxskb), *dh;
const u32 dccp_hdr_reset_len = sizeof(struct dccp_hdr) +
@ -805,7 +805,7 @@ static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
return 0;
reset:
dccp_v6_ctl_send_reset(skb);
dccp_v6_ctl_send_reset(sk, skb);
discard:
if (opt_skb != NULL)
__kfree_skb(opt_skb);
@ -902,7 +902,7 @@ no_dccp_socket:
if (dh->dccph_type != DCCP_PKT_RESET) {
DCCP_SKB_CB(skb)->dccpd_reset_code =
DCCP_RESET_CODE_NO_CONNECTION;
dccp_v6_ctl_send_reset(skb);
dccp_v6_ctl_send_reset(sk, skb);
}
discard_it:

2
net/dccp/minisocks.c
Просмотреть файл

@ -246,7 +246,7 @@ listen_overflow:
DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY;
drop:
if (dccp_hdr(skb)->dccph_type != DCCP_PKT_RESET)
req->rsk_ops->send_reset(skb);
req->rsk_ops->send_reset(sk, skb);
inet_csk_reqsk_queue_drop(sk, req, prev);
goto out;

16
net/ipv4/Kconfig
Просмотреть файл

@ -618,5 +618,21 @@ config DEFAULT_TCP_CONG
default "reno" if DEFAULT_RENO
default "cubic"
config TCP_MD5SIG
bool "TCP: MD5 Signature Option support (RFC2385) (EXPERIMENTAL)"
depends on EXPERIMENTAL
select CRYPTO
select CRYPTO_MD5
---help---
RFC2385 specifices a method of giving MD5 protection to TCP sessions.
Its main (only?) use is to protect BGP sessions between core routers
on the Internet.
If unsure, say N.
config TCP_MD5SIG_DEBUG
bool "TCP: MD5 Signature Option debugging"
depends on TCP_MD5SIG
source "net/ipv4/ipvs/Kconfig"

137
net/ipv4/tcp.c
Просмотреть файл

@ -258,6 +258,7 @@
#include <linux/bootmem.h>
#include <linux/cache.h>
#include <linux/err.h>
#include <linux/crypto.h>
#include <net/icmp.h>
#include <net/tcp.h>
@ -1942,6 +1943,13 @@ static int do_tcp_setsockopt(struct sock *sk, int level,
}
break;
#ifdef CONFIG_TCP_MD5SIG
case TCP_MD5SIG:
/* Read the IP->Key mappings from userspace */
err = tp->af_specific->md5_parse(sk, optval, optlen);
break;
#endif
default:
err = -ENOPROTOOPT;
break;
@ -2231,6 +2239,135 @@ out:
}
EXPORT_SYMBOL(tcp_tso_segment);
#ifdef CONFIG_TCP_MD5SIG
static unsigned long tcp_md5sig_users;
static struct tcp_md5sig_pool **tcp_md5sig_pool;
static DEFINE_SPINLOCK(tcp_md5sig_pool_lock);
static void __tcp_free_md5sig_pool(struct tcp_md5sig_pool **pool)
{
int cpu;
for_each_possible_cpu(cpu) {
struct tcp_md5sig_pool *p = *per_cpu_ptr(pool, cpu);
if (p) {
if (p->md5_desc.tfm)
crypto_free_hash(p->md5_desc.tfm);
kfree(p);
p = NULL;
}
}
free_percpu(pool);
}
void tcp_free_md5sig_pool(void)
{
struct tcp_md5sig_pool **pool = NULL;
spin_lock(&tcp_md5sig_pool_lock);
if (--tcp_md5sig_users == 0) {
pool = tcp_md5sig_pool;
tcp_md5sig_pool = NULL;
}
spin_unlock(&tcp_md5sig_pool_lock);
if (pool)
__tcp_free_md5sig_pool(pool);
}
EXPORT_SYMBOL(tcp_free_md5sig_pool);
struct tcp_md5sig_pool **__tcp_alloc_md5sig_pool(void)
{
int cpu;
struct tcp_md5sig_pool **pool;
pool = alloc_percpu(struct tcp_md5sig_pool *);
if (!pool)
return NULL;
for_each_possible_cpu(cpu) {
struct tcp_md5sig_pool *p;
struct crypto_hash *hash;
p = kzalloc(sizeof(*p), GFP_KERNEL);
if (!p)
goto out_free;
*per_cpu_ptr(pool, cpu) = p;
hash = crypto_alloc_hash("md5", 0, CRYPTO_ALG_ASYNC);
if (!hash || IS_ERR(hash))
goto out_free;
p->md5_desc.tfm = hash;
}
return pool;
out_free:
__tcp_free_md5sig_pool(pool);
return NULL;
}
struct tcp_md5sig_pool **tcp_alloc_md5sig_pool(void)
{
struct tcp_md5sig_pool **pool;
int alloc = 0;
retry:
spin_lock(&tcp_md5sig_pool_lock);
pool = tcp_md5sig_pool;
if (tcp_md5sig_users++ == 0) {
alloc = 1;
spin_unlock(&tcp_md5sig_pool_lock);
} else if (!pool) {
tcp_md5sig_users--;
spin_unlock(&tcp_md5sig_pool_lock);
cpu_relax();
goto retry;
} else
spin_unlock(&tcp_md5sig_pool_lock);
if (alloc) {
/* we cannot hold spinlock here because this may sleep. */
struct tcp_md5sig_pool **p = __tcp_alloc_md5sig_pool();
spin_lock(&tcp_md5sig_pool_lock);
if (!p) {
tcp_md5sig_users--;
spin_unlock(&tcp_md5sig_pool_lock);
return NULL;
}
pool = tcp_md5sig_pool;
if (pool) {
/* oops, it has already been assigned. */
spin_unlock(&tcp_md5sig_pool_lock);
__tcp_free_md5sig_pool(p);
} else {
tcp_md5sig_pool = pool = p;
spin_unlock(&tcp_md5sig_pool_lock);
}
}
return pool;
}
EXPORT_SYMBOL(tcp_alloc_md5sig_pool);
struct tcp_md5sig_pool *__tcp_get_md5sig_pool(int cpu)
{
struct tcp_md5sig_pool **p;
spin_lock(&tcp_md5sig_pool_lock);
p = tcp_md5sig_pool;
if (p)
tcp_md5sig_users++;
spin_unlock(&tcp_md5sig_pool_lock);
return (p ? *per_cpu_ptr(p, cpu) : NULL);
}
EXPORT_SYMBOL(__tcp_get_md5sig_pool);
void __tcp_put_md5sig_pool(void) {
__tcp_free_md5sig_pool(tcp_md5sig_pool);
}
EXPORT_SYMBOL(__tcp_put_md5sig_pool);
#endif
extern void __skb_cb_too_small_for_tcp(int, int);
extern struct tcp_congestion_ops tcp_reno;

8
net/ipv4/tcp_input.c
Просмотреть файл

@ -2677,6 +2677,14 @@ void tcp_parse_options(struct sk_buff *skb, struct tcp_options_received *opt_rx,
opt_rx->sack_ok) {
TCP_SKB_CB(skb)->sacked = (ptr - 2) - (unsigned char *)th;
}
#ifdef CONFIG_TCP_MD5SIG
case TCPOPT_MD5SIG:
/*
* The MD5 Hash has already been
* checked (see tcp_v{4,6}_do_rcv()).
*/
break;
#endif
};
ptr+=opsize-2;
length-=opsize;

673
net/ipv4/tcp_ipv4.c
Просмотреть файл

@ -78,6 +78,9 @@
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/crypto.h>
#include <linux/scatterlist.h>
int sysctl_tcp_tw_reuse __read_mostly;
int sysctl_tcp_low_latency __read_mostly;
@ -89,6 +92,13 @@ static struct socket *tcp_socket;
void tcp_v4_send_check(struct sock *sk, int len, struct sk_buff *skb);
#ifdef CONFIG_TCP_MD5SIG
static struct tcp_md5sig_key *tcp_v4_md5_do_lookup(struct sock *sk, __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, int tcplen);
#endif
struct inet_hashinfo __cacheline_aligned tcp_hashinfo = {
.lhash_lock = __RW_LOCK_UNLOCKED(tcp_hashinfo.lhash_lock),
.lhash_users = ATOMIC_INIT(0),
@ -526,11 +536,19 @@ int tcp_v4_gso_send_check(struct sk_buff *skb)
* Exception: precedence violation. We do not implement it in any case.
*/
static void tcp_v4_send_reset(struct sk_buff *skb)
static void tcp_v4_send_reset(struct sock *sk, struct sk_buff *skb)
{
struct tcphdr *th = skb->h.th;
struct tcphdr rth;
struct {
struct tcphdr th;
#ifdef CONFIG_TCP_MD5SIG
u32 opt[(TCPOLEN_MD5SIG_ALIGNED >> 2)];
#endif
} rep;
struct ip_reply_arg arg;
#ifdef CONFIG_TCP_MD5SIG
struct tcp_md5sig_key *key;
#endif
/* Never send a reset in response to a reset. */
if (th->rst)
@ -540,29 +558,50 @@ static void tcp_v4_send_reset(struct sk_buff *skb)
return;
/* Swap the send and the receive. */
memset(&rth, 0, sizeof(struct tcphdr));
rth.dest = th->source;
rth.source = th->dest;
rth.doff = sizeof(struct tcphdr) / 4;
rth.rst = 1;
memset(&rep, 0, sizeof(rep));
rep.th.dest = th->source;
rep.th.source = th->dest;
rep.th.doff = sizeof(struct tcphdr) / 4;
rep.th.rst = 1;
if (th->ack) {
rth.seq = th->ack_seq;
rep.th.seq = th->ack_seq;
} else {
rth.ack = 1;
rth.ack_seq = htonl(ntohl(th->seq) + th->syn + th->fin +
skb->len - (th->doff << 2));
rep.th.ack = 1;
rep.th.ack_seq = htonl(ntohl(th->seq) + th->syn + th->fin +
skb->len - (th->doff << 2));
}
memset(&arg, 0, sizeof arg);
arg.iov[0].iov_base = (unsigned char *)&rth;
arg.iov[0].iov_len = sizeof rth;
arg.iov[0].iov_base = (unsigned char *)&rep;
arg.iov[0].iov_len = sizeof(rep.th);
#ifdef CONFIG_TCP_MD5SIG
key = sk ? tcp_v4_md5_do_lookup(sk, skb->nh.iph->daddr) : NULL;
if (key) {
rep.opt[0] = htonl((TCPOPT_NOP << 24) |
(TCPOPT_NOP << 16) |
(TCPOPT_MD5SIG << 8) |
TCPOLEN_MD5SIG);
/* Update length and the length the header thinks exists */
arg.iov[0].iov_len += TCPOLEN_MD5SIG_ALIGNED;
rep.th.doff = arg.iov[0].iov_len / 4;
tcp_v4_do_calc_md5_hash((__u8 *)&rep.opt[1],
key,
skb->nh.iph->daddr,
skb->nh.iph->saddr,
&rep.th, IPPROTO_TCP,
arg.iov[0].iov_len);
}
#endif
arg.csum = csum_tcpudp_nofold(skb->nh.iph->daddr,
skb->nh.iph->saddr, /*XXX*/
sizeof(struct tcphdr), IPPROTO_TCP, 0);
arg.csumoffset = offsetof(struct tcphdr, check) / 2;
ip_send_reply(tcp_socket->sk, skb, &arg, sizeof rth);
ip_send_reply(tcp_socket->sk, skb, &arg, arg.iov[0].iov_len);
TCP_INC_STATS_BH(TCP_MIB_OUTSEGS);
TCP_INC_STATS_BH(TCP_MIB_OUTRSTS);
@ -572,15 +611,24 @@ static void tcp_v4_send_reset(struct sk_buff *skb)
outside socket context is ugly, certainly. What can I do?
*/
static void tcp_v4_send_ack(struct sk_buff *skb, u32 seq, u32 ack,
static void tcp_v4_send_ack(struct tcp_timewait_sock *twsk,
struct sk_buff *skb, u32 seq, u32 ack,
u32 win, u32 ts)
{
struct tcphdr *th = skb->h.th;
struct {
struct tcphdr th;
u32 tsopt[TCPOLEN_TSTAMP_ALIGNED >> 2];
u32 opt[(TCPOLEN_TSTAMP_ALIGNED >> 2)
#ifdef CONFIG_TCP_MD5SIG
+ (TCPOLEN_MD5SIG_ALIGNED >> 2)
#endif
];
} 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);
@ -588,12 +636,12 @@ static void tcp_v4_send_ack(struct sk_buff *skb, u32 seq, u32 ack,
arg.iov[0].iov_base = (unsigned char *)&rep;
arg.iov[0].iov_len = sizeof(rep.th);
if (ts) {
rep.tsopt[0] = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) |
(TCPOPT_TIMESTAMP << 8) |
TCPOLEN_TIMESTAMP);
rep.tsopt[1] = htonl(tcp_time_stamp);
rep.tsopt[2] = htonl(ts);
arg.iov[0].iov_len = sizeof(rep);
rep.opt[0] = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) |
(TCPOPT_TIMESTAMP << 8) |
TCPOLEN_TIMESTAMP);
rep.opt[1] = htonl(tcp_time_stamp);
rep.opt[2] = htonl(ts);
arg.iov[0].iov_len = TCPOLEN_TSTAMP_ALIGNED;
}
/* Swap the send and the receive. */
@ -605,6 +653,44 @@ static void tcp_v4_send_ack(struct sk_buff *skb, u32 seq, u32 ack,
rep.th.ack = 1;
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, skb->nh.iph->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;
rep.opt[offset++] = htonl((TCPOPT_NOP << 24) |
(TCPOPT_NOP << 16) |
(TCPOPT_MD5SIG << 8) |
TCPOLEN_MD5SIG);
arg.iov[0].iov_len += TCPOLEN_MD5SIG_ALIGNED;
rep.th.doff = arg.iov[0].iov_len/4;
tcp_v4_do_calc_md5_hash((__u8 *)&rep.opt[offset],
key,
skb->nh.iph->daddr,
skb->nh.iph->saddr,
&rep.th, IPPROTO_TCP,
arg.iov[0].iov_len);
}
#endif
arg.csum = csum_tcpudp_nofold(skb->nh.iph->daddr,
skb->nh.iph->saddr, /*XXX*/
arg.iov[0].iov_len, IPPROTO_TCP, 0);
@ -618,9 +704,9 @@ static void tcp_v4_send_ack(struct sk_buff *skb, u32 seq, u32 ack,
static void tcp_v4_timewait_ack(struct sock *sk, struct sk_buff *skb)
{
struct inet_timewait_sock *tw = inet_twsk(sk);
const struct tcp_timewait_sock *tcptw = tcp_twsk(sk);
struct tcp_timewait_sock *tcptw = tcp_twsk(sk);
tcp_v4_send_ack(skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt,
tcp_v4_send_ack(tcptw, skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt,
tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, tcptw->tw_ts_recent);
inet_twsk_put(tw);
@ -628,7 +714,8 @@ static void tcp_v4_timewait_ack(struct sock *sk, struct sk_buff *skb)
static void tcp_v4_reqsk_send_ack(struct sk_buff *skb, struct request_sock *req)
{
tcp_v4_send_ack(skb, tcp_rsk(req)->snt_isn + 1, tcp_rsk(req)->rcv_isn + 1, req->rcv_wnd,
tcp_v4_send_ack(NULL, skb, tcp_rsk(req)->snt_isn + 1,
tcp_rsk(req)->rcv_isn + 1, req->rcv_wnd,
req->ts_recent);
}
@ -714,6 +801,461 @@ static struct ip_options *tcp_v4_save_options(struct sock *sk,
return dopt;
}
#ifdef CONFIG_TCP_MD5SIG
/*
* RFC2385 MD5 checksumming requires a mapping of
* IP address->MD5 Key.
* We need to maintain these in the sk structure.
*/
/* Find the Key structure for an address. */
static struct tcp_md5sig_key *tcp_v4_md5_do_lookup(struct sock *sk, __be32 addr)
{
struct tcp_sock *tp = tcp_sk(sk);
int i;
if (!tp->md5sig_info || !tp->md5sig_info->entries4)
return NULL;
for (i = 0; i < tp->md5sig_info->entries4; i++) {
if (tp->md5sig_info->keys4[i].addr == addr)
return (struct tcp_md5sig_key *)&tp->md5sig_info->keys4[i];
}
return NULL;
}
struct tcp_md5sig_key *tcp_v4_md5_lookup(struct sock *sk,
struct sock *addr_sk)
{
return tcp_v4_md5_do_lookup(sk, inet_sk(addr_sk)->daddr);
}
EXPORT_SYMBOL(tcp_v4_md5_lookup);
struct tcp_md5sig_key *tcp_v4_reqsk_md5_lookup(struct sock *sk,
struct request_sock *req)
{
return tcp_v4_md5_do_lookup(sk, inet_rsk(req)->rmt_addr);
}
/* This can be called on a newly created socket, from other files */
int tcp_v4_md5_do_add(struct sock *sk, __be32 addr,
u8 *newkey, u8 newkeylen)
{
/* Add Key to the list */
struct tcp4_md5sig_key *key;
struct tcp_sock *tp = tcp_sk(sk);
struct tcp4_md5sig_key *keys;
key = (struct tcp4_md5sig_key *) tcp_v4_md5_do_lookup(sk, addr);
if (key) {
/* Pre-existing entry - just update that one. */
kfree (key->key);
key->key = newkey;
key->keylen = newkeylen;
} else {
if (!tp->md5sig_info) {
tp->md5sig_info = kzalloc(sizeof(*tp->md5sig_info), GFP_ATOMIC);
if (!tp->md5sig_info) {
kfree(newkey);
return -ENOMEM;
}
}
if (tcp_alloc_md5sig_pool() == NULL) {
kfree(newkey);
return -ENOMEM;
}
if (tp->md5sig_info->alloced4 == tp->md5sig_info->entries4) {
keys = kmalloc((sizeof(struct tcp4_md5sig_key) *
(tp->md5sig_info->entries4 + 1)), GFP_ATOMIC);
if (!keys) {
kfree(newkey);
tcp_free_md5sig_pool();
return -ENOMEM;
}
if (tp->md5sig_info->entries4)
memcpy(keys, tp->md5sig_info->keys4,
(sizeof (struct tcp4_md5sig_key) *
tp->md5sig_info->entries4));
/* Free old key list, and reference new one */
if (tp->md5sig_info->keys4)
kfree(tp->md5sig_info->keys4);
tp->md5sig_info->keys4 = keys;
tp->md5sig_info->alloced4++;
}
tp->md5sig_info->entries4++;
tp->md5sig_info->keys4[tp->md5sig_info->entries4 - 1].addr = addr;
tp->md5sig_info->keys4[tp->md5sig_info->entries4 - 1].key = newkey;
tp->md5sig_info->keys4[tp->md5sig_info->entries4 - 1].keylen = newkeylen;
}
return 0;
}
EXPORT_SYMBOL(tcp_v4_md5_do_add);
static int tcp_v4_md5_add_func(struct sock *sk, struct sock *addr_sk,
u8 *newkey, u8 newkeylen)
{
return tcp_v4_md5_do_add(sk, inet_sk(addr_sk)->daddr,
newkey, newkeylen);
}
int tcp_v4_md5_do_del(struct sock *sk, __be32 addr)
{
struct tcp_sock *tp = tcp_sk(sk);
int i;
for (i = 0; i < tp->md5sig_info->entries4; i++) {
if (tp->md5sig_info->keys4[i].addr == addr) {
/* Free the key */
kfree(tp->md5sig_info->keys4[i].key);
tp->md5sig_info->entries4--;
if (tp->md5sig_info->entries4 == 0) {
kfree(tp->md5sig_info->keys4);
tp->md5sig_info->keys4 = NULL;
} else {
/* Need to do some manipulation */
if (tp->md5sig_info->entries4 != i)
memcpy(&tp->md5sig_info->keys4[i],
&tp->md5sig_info->keys4[i+1],
(tp->md5sig_info->entries4 - i)
* sizeof (struct tcp4_md5sig_key));
}
tcp_free_md5sig_pool();
return 0;
}
}
return -ENOENT;
}
EXPORT_SYMBOL(tcp_v4_md5_do_del);
static void tcp_v4_clear_md5_list (struct sock *sk)
{
struct tcp_sock *tp = tcp_sk(sk);
/* Free each key, then the set of key keys,
* the crypto element, and then decrement our
* hold on the last resort crypto.
*/
if (tp->md5sig_info->entries4) {
int i;
for (i = 0; i < tp->md5sig_info->entries4; i++)
kfree(tp->md5sig_info->keys4[i].key);
tp->md5sig_info->entries4 = 0;
tcp_free_md5sig_pool();
}
if (tp->md5sig_info->keys4) {
kfree(tp->md5sig_info->keys4);
tp->md5sig_info->keys4 = NULL;
tp->md5sig_info->alloced4 = 0;
}
}
static int tcp_v4_parse_md5_keys (struct sock *sk, char __user *optval,
int optlen)
{
struct tcp_md5sig cmd;
struct sockaddr_in *sin = (struct sockaddr_in *)&cmd.tcpm_addr;
u8 *newkey;
if (optlen < sizeof(cmd))
return -EINVAL;
if (copy_from_user (&cmd, optval, sizeof(cmd)))
return -EFAULT;
if (sin->sin_family != AF_INET)
return -EINVAL;
if (!cmd.tcpm_key || !cmd.tcpm_keylen) {
if (!tcp_sk(sk)->md5sig_info)
return -ENOENT;
return tcp_v4_md5_do_del(sk, sin->sin_addr.s_addr);
}
if (cmd.tcpm_keylen > TCP_MD5SIG_MAXKEYLEN)
return -EINVAL;
if (!tcp_sk(sk)->md5sig_info) {
struct tcp_sock *tp = tcp_sk(sk);
struct tcp_md5sig_info *p;
p = kzalloc(sizeof(struct tcp_md5sig_info), GFP_KERNEL);
if (!p)
return -EINVAL;
tp->md5sig_info = p;
}
newkey = kmalloc(cmd.tcpm_keylen, GFP_KERNEL);
if (!newkey)
return -ENOMEM;
memcpy(newkey, cmd.tcpm_key, cmd.tcpm_keylen);
return tcp_v4_md5_do_add(sk, sin->sin_addr.s_addr,
newkey, cmd.tcpm_keylen);
}
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,
int tcplen)
{
struct scatterlist sg[4];
__u16 data_len;
int block = 0;
#ifdef CONFIG_TCP_MD5SIG_DEBUG
int i;
#endif
__u16 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,
* so we need to generate the MD5 hash for the packet now.
*/
hp = tcp_get_md5sig_pool();
if (!hp)
goto clear_hash_noput;
bp = &hp->md5_blk.ip4;
desc = &hp->md5_desc;
/*
* 1. 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->len = htons(tcplen);
sg_set_buf(&sg[block++], bp, sizeof(*bp));
nbytes += sizeof(*bp);
#ifdef CONFIG_TCP_MD5SIG_DEBUG
printk("Calcuating hash for: ");
for (i = 0; i < sizeof (*bp); i++)
printk ("%02x ", (unsigned int)((unsigned char *)bp)[i]);
printk(" ");
#endif
/* 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);
#ifdef CONFIG_TCP_MD5SIG_DEBUG
for (i = 0; i < sizeof (struct tcphdr); i++)
printk (" %02x", (unsigned int)((unsigned char *)th)[i]);
#endif
/* 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;
#ifdef CONFIG_TCP_MD5SIG_DEBUG
printk (" and password: ");
for (i = 0; i < key->keylen; i++)
printk ("%02x ", (unsigned int)key->key[i]);
#endif
/* 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);
if (err)
goto clear_hash;
/* Reset header, and free up the crypto */
tcp_put_md5sig_pool();
th->check = old_checksum;
out:
#ifdef CONFIG_TCP_MD5SIG_DEBUG
printk(" result:");
for (i = 0; i < 16; i++)
printk (" %02x", (unsigned int)(((u8*)md5_hash)[i]));
printk("\n");
#endif
return 0;
clear_hash:
tcp_put_md5sig_pool();
clear_hash_noput:
memset(md5_hash, 0, 16);
goto out;
}
int tcp_v4_calc_md5_hash(char *md5_hash, struct tcp_md5sig_key *key,
struct sock *sk,
struct dst_entry *dst,
struct request_sock *req,
struct tcphdr *th, int protocol,
int tcplen)
{
__be32 saddr, daddr;
if (sk) {
saddr = inet_sk(sk)->saddr;
daddr = inet_sk(sk)->daddr;
} else {
struct rtable *rt = (struct rtable *)dst;
BUG_ON(!rt);
saddr = rt->rt_src;
daddr = rt->rt_dst;
}
return tcp_v4_do_calc_md5_hash(md5_hash, key,
saddr, daddr,
th, protocol, tcplen);
}
EXPORT_SYMBOL(tcp_v4_calc_md5_hash);
static int tcp_v4_inbound_md5_hash (struct sock *sk, struct sk_buff *skb)
{
/*
* This gets called for each TCP segment that arrives
* so we want to be efficient.
* We have 3 drop cases:
* o No MD5 hash and one expected.
* o MD5 hash and we're not expecting one.
* o MD5 hash and its wrong.
*/
__u8 *hash_location = NULL;
struct tcp_md5sig_key *hash_expected;
struct iphdr *iph = skb->nh.iph;
struct tcphdr *th = skb->h.th;
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);
/*
* 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;
if (hash_expected && !hash_location) {
if (net_ratelimit()) {
printk(KERN_INFO "MD5 Hash NOT expected but found "
"(" NIPQUAD_FMT ", %d)->(" NIPQUAD_FMT ", %d)\n",
NIPQUAD (iph->saddr), ntohs(th->source),
NIPQUAD (iph->daddr), ntohs(th->dest));
}
return 1;
}
if (!hash_expected && hash_location) {
if (net_ratelimit()) {
printk(KERN_INFO "MD5 Hash NOT expected but found "
"(" NIPQUAD_FMT ", %d)->(" NIPQUAD_FMT ", %d)\n",
NIPQUAD (iph->saddr), ntohs(th->source),
NIPQUAD (iph->daddr), ntohs(th->dest));
}
return 1;
}
/* Okay, so this is hash_expected and hash_location -
* so we need to calculate the checksum.
*/
genhash = tcp_v4_do_calc_md5_hash(newhash,
hash_expected,
iph->saddr, iph->daddr,
th, sk->sk_protocol,
skb->len);
if (genhash || memcmp(hash_location, newhash, 16) != 0) {
if (net_ratelimit()) {
printk(KERN_INFO "MD5 Hash failed for "
"(" NIPQUAD_FMT ", %d)->(" NIPQUAD_FMT ", %d)%s\n",
NIPQUAD (iph->saddr), ntohs(th->source),
NIPQUAD (iph->daddr), ntohs(th->dest),
genhash ? " tcp_v4_calc_md5_hash failed" : "");
#ifdef CONFIG_TCP_MD5SIG_DEBUG
do {
int i;
printk("Received: ");
for (i = 0; i < 16; i++)
printk("%02x ", 0xff & (int)hash_location[i]);
printk("\n");
printk("Calculated: ");
for (i = 0; i < 16; i++)
printk("%02x ", 0xff & (int)newhash[i]);
printk("\n");
} while(0);
#endif
}
return 1;
}
return 0;
}
#endif
struct request_sock_ops tcp_request_sock_ops __read_mostly = {
.family = PF_INET,
.obj_size = sizeof(struct tcp_request_sock),
@ -723,9 +1265,16 @@ struct request_sock_ops tcp_request_sock_ops __read_mostly = {
.send_reset = tcp_v4_send_reset,
};
struct tcp_request_sock_ops tcp_request_sock_ipv4_ops = {
#ifdef CONFIG_TCP_MD5SIG
.md5_lookup = tcp_v4_reqsk_md5_lookup,
#endif
};
static struct timewait_sock_ops tcp_timewait_sock_ops = {
.twsk_obj_size = sizeof(struct tcp_timewait_sock),
.twsk_unique = tcp_twsk_unique,
.twsk_destructor= tcp_twsk_destructor,
};
int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
@ -773,6 +1322,10 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
if (!req)
goto drop;
#ifdef CONFIG_TCP_MD5SIG
tcp_rsk(req)->af_specific = &tcp_request_sock_ipv4_ops;
#endif
tcp_clear_options(&tmp_opt);
tmp_opt.mss_clamp = 536;
tmp_opt.user_mss = tcp_sk(sk)->rx_opt.user_mss;
@ -891,6 +1444,9 @@ struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
struct inet_sock *newinet;
struct tcp_sock *newtp;
struct sock *newsk;
#ifdef CONFIG_TCP_MD5SIG
struct tcp_md5sig_key *key;
#endif
if (sk_acceptq_is_full(sk))
goto exit_overflow;
@ -925,6 +1481,24 @@ struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
newtp->advmss = dst_metric(dst, RTAX_ADVMSS);
tcp_initialize_rcv_mss(newsk);
#ifdef CONFIG_TCP_MD5SIG
/* Copy over the MD5 key from the original socket */
if ((key = tcp_v4_md5_do_lookup(sk, newinet->daddr)) != NULL) {
/*
* We're using one, so create a matching key
* on the newsk structure. If we fail to get
* memory, then we end up not copying the key
* across. Shucks.
*/
char *newkey = kmalloc(key->keylen, GFP_ATOMIC);
if (newkey) {
memcpy(newkey, key->key, key->keylen);
tcp_v4_md5_do_add(newsk, inet_sk(sk)->daddr,
newkey, key->keylen);
}
}
#endif
__inet_hash(&tcp_hashinfo, newsk, 0);
__inet_inherit_port(&tcp_hashinfo, sk, newsk);
@ -1000,10 +1574,24 @@ static int tcp_v4_checksum_init(struct sk_buff *skb)
*/
int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
{
struct sock *rsk;
#ifdef CONFIG_TCP_MD5SIG
/*
* We really want to reject the packet as early as possible
* if:
* o We're expecting an MD5'd packet and this is no MD5 tcp option
* o There is an MD5 option and we're not expecting one
*/
if (tcp_v4_inbound_md5_hash (sk, skb))
goto discard;
#endif
if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */
TCP_CHECK_TIMER(sk);
if (tcp_rcv_established(sk, skb, skb->h.th, skb->len))
if (tcp_rcv_established(sk, skb, skb->h.th, skb->len)) {
rsk = sk;
goto reset;
}
TCP_CHECK_TIMER(sk);
return 0;
}
@ -1017,20 +1605,24 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
goto discard;
if (nsk != sk) {
if (tcp_child_process(sk, nsk, skb))
if (tcp_child_process(sk, nsk, skb)) {
rsk = nsk;
goto reset;
}
return 0;
}
}
TCP_CHECK_TIMER(sk);
if (tcp_rcv_state_process(sk, skb, skb->h.th, skb->len))
if (tcp_rcv_state_process(sk, skb, skb->h.th, skb->len)) {
rsk = sk;
goto reset;
}
TCP_CHECK_TIMER(sk);
return 0;
reset:
tcp_v4_send_reset(skb);
tcp_v4_send_reset(rsk, skb);
discard:
kfree_skb(skb);
/* Be careful here. If this function gets more complicated and
@ -1139,7 +1731,7 @@ no_tcp_socket:
bad_packet:
TCP_INC_STATS_BH(TCP_MIB_INERRS);
} else {
tcp_v4_send_reset(skb);
tcp_v4_send_reset(NULL, skb);
}
discard_it:
@ -1262,6 +1854,15 @@ struct inet_connection_sock_af_ops ipv4_specific = {
#endif
};
struct tcp_sock_af_ops tcp_sock_ipv4_specific = {
#ifdef CONFIG_TCP_MD5SIG
.md5_lookup = tcp_v4_md5_lookup,
.calc_md5_hash = tcp_v4_calc_md5_hash,
.md5_add = tcp_v4_md5_add_func,
.md5_parse = tcp_v4_parse_md5_keys,
#endif
};
/* NOTE: A lot of things set to zero explicitly by call to
* sk_alloc() so need not be done here.
*/
@ -1301,6 +1902,9 @@ static int tcp_v4_init_sock(struct sock *sk)
icsk->icsk_af_ops = &ipv4_specific;
icsk->icsk_sync_mss = tcp_sync_mss;
#ifdef CONFIG_TCP_MD5SIG
tp->af_specific = &tcp_sock_ipv4_specific;
#endif
sk->sk_sndbuf = sysctl_tcp_wmem[1];
sk->sk_rcvbuf = sysctl_tcp_rmem[1];
@ -1324,6 +1928,15 @@ int tcp_v4_destroy_sock(struct sock *sk)
/* Cleans up our, hopefully empty, out_of_order_queue. */
__skb_queue_purge(&tp->out_of_order_queue);
#ifdef CONFIG_TCP_MD5SIG
/* Clean up the MD5 key list, if any */
if (tp->md5sig_info) {
tcp_v4_clear_md5_list(sk);
kfree(tp->md5sig_info);
tp->md5sig_info = NULL;
}
#endif
#ifdef CONFIG_NET_DMA
/* Cleans up our sk_async_wait_queue */
__skb_queue_purge(&sk->sk_async_wait_queue);

64
net/ipv4/tcp_minisocks.c
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@ -306,6 +306,28 @@ void tcp_time_wait(struct sock *sk, int state, int timeo)
tw->tw_ipv6only = np->ipv6only;
}
#endif
#ifdef CONFIG_TCP_MD5SIG
/*
* The timewait bucket does not have the key DB from the
* sock structure. We just make a quick copy of the
* md5 key being used (if indeed we are using one)
* so the timewait ack generating code has the key.
*/
do {
struct tcp_md5sig_key *key;
memset(tcptw->tw_md5_key, 0, sizeof(tcptw->tw_md5_key));
tcptw->tw_md5_keylen = 0;
key = tp->af_specific->md5_lookup(sk, sk);
if (key != NULL) {
memcpy(&tcptw->tw_md5_key, key->key, key->keylen);
tcptw->tw_md5_keylen = key->keylen;
if (tcp_alloc_md5sig_pool() == NULL)
BUG();
}
} while(0);
#endif
/* Linkage updates. */
__inet_twsk_hashdance(tw, sk, &tcp_hashinfo);
@ -337,6 +359,17 @@ void tcp_time_wait(struct sock *sk, int state, int timeo)
tcp_done(sk);
}
void tcp_twsk_destructor(struct sock *sk)
{
struct tcp_timewait_sock *twsk = tcp_twsk(sk);
#ifdef CONFIG_TCP_MD5SIG
if (twsk->tw_md5_keylen)
tcp_put_md5sig_pool();
#endif
}
EXPORT_SYMBOL_GPL(tcp_twsk_destructor);
/* This is not only more efficient than what we used to do, it eliminates
* a lot of code duplication between IPv4/IPv6 SYN recv processing. -DaveM
*
@ -435,6 +468,11 @@ struct sock *tcp_create_openreq_child(struct sock *sk, struct request_sock *req,
newtp->rx_opt.ts_recent_stamp = 0;
newtp->tcp_header_len = sizeof(struct tcphdr);
}
#ifdef CONFIG_TCP_MD5SIG
newtp->md5sig_info = NULL; /*XXX*/
if (newtp->af_specific->md5_lookup(sk, newsk))
newtp->tcp_header_len += TCPOLEN_MD5SIG_ALIGNED;
#endif
if (skb->len >= TCP_MIN_RCVMSS+newtp->tcp_header_len)
newicsk->icsk_ack.last_seg_size = skb->len - newtp->tcp_header_len;
newtp->rx_opt.mss_clamp = req->mss;
@ -617,6 +655,30 @@ struct sock *tcp_check_req(struct sock *sk,struct sk_buff *skb,
req, NULL);
if (child == NULL)
goto listen_overflow;
#ifdef CONFIG_TCP_MD5SIG
else {
/* Copy over the MD5 key from the original socket */
struct tcp_md5sig_key *key;
struct tcp_sock *tp = tcp_sk(sk);
key = tp->af_specific->md5_lookup(sk, child);
if (key != NULL) {
/*
* We're using one, so create a matching key on the
* newsk structure. If we fail to get memory then we
* end up not copying the key across. Shucks.
*/
char *newkey = kmalloc(key->keylen, GFP_ATOMIC);
if (newkey) {
if (!tcp_alloc_md5sig_pool())
BUG();
memcpy(newkey, key->key, key->keylen);
tp->af_specific->md5_add(child, child,
newkey,
key->keylen);
}
}
}
#endif
inet_csk_reqsk_queue_unlink(sk, req, prev);
inet_csk_reqsk_queue_removed(sk, req);
@ -633,7 +695,7 @@ struct sock *tcp_check_req(struct sock *sk,struct sk_buff *skb,
embryonic_reset:
NET_INC_STATS_BH(LINUX_MIB_EMBRYONICRSTS);
if (!(flg & TCP_FLAG_RST))
req->rsk_ops->send_reset(skb);
req->rsk_ops->send_reset(sk, skb);
inet_csk_reqsk_queue_drop(sk, req, prev);
return NULL;

111
net/ipv4/tcp_output.c
Просмотреть файл

@ -270,7 +270,7 @@ static u16 tcp_select_window(struct sock *sk)
}
static void tcp_build_and_update_options(__be32 *ptr, struct tcp_sock *tp,
__u32 tstamp)
__u32 tstamp, __u8 **md5_hash)
{
if (tp->rx_opt.tstamp_ok) {
*ptr++ = htonl((TCPOPT_NOP << 24) |
@ -298,16 +298,29 @@ static void tcp_build_and_update_options(__be32 *ptr, struct tcp_sock *tp,
tp->rx_opt.eff_sacks--;
}
}
#ifdef CONFIG_TCP_MD5SIG
if (md5_hash) {
*ptr++ = htonl((TCPOPT_NOP << 24) |
(TCPOPT_NOP << 16) |
(TCPOPT_MD5SIG << 8) |
TCPOLEN_MD5SIG);
*md5_hash = (__u8 *)ptr;
}
#endif
}
/* Construct a tcp options header for a SYN or SYN_ACK packet.
* If this is every changed make sure to change the definition of
* MAX_SYN_SIZE to match the new maximum number of options that you
* can generate.
*
* Note - that with the RFC2385 TCP option, we make room for the
* 16 byte MD5 hash. This will be filled in later, so the pointer for the
* location to be filled is passed back up.
*/
static void tcp_syn_build_options(__be32 *ptr, int mss, int ts, int sack,
int offer_wscale, int wscale, __u32 tstamp,
__u32 ts_recent)
__u32 ts_recent, __u8 **md5_hash)
{
/* We always get an MSS option.
* The option bytes which will be seen in normal data
@ -346,6 +359,20 @@ static void tcp_syn_build_options(__be32 *ptr, int mss, int ts, int sack,
(TCPOPT_WINDOW << 16) |
(TCPOLEN_WINDOW << 8) |
(wscale));
#ifdef CONFIG_TCP_MD5SIG
/*
* If MD5 is enabled, then we set the option, and include the size
* (always 18). The actual MD5 hash is added just before the
* packet is sent.
*/
if (md5_hash) {
*ptr++ = htonl((TCPOPT_NOP << 24) |
(TCPOPT_NOP << 16) |
(TCPOPT_MD5SIG << 8) |
TCPOLEN_MD5SIG);
*md5_hash = (__u8 *) ptr;
}
#endif
}
/* This routine actually transmits TCP packets queued in by
@ -366,6 +393,10 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
struct tcp_sock *tp;
struct tcp_skb_cb *tcb;
int tcp_header_size;
#ifdef CONFIG_TCP_MD5SIG
struct tcp_md5sig_key *md5;
__u8 *md5_hash_location;
#endif
struct tcphdr *th;
int sysctl_flags;
int err;
@ -424,6 +455,16 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
if (tcp_packets_in_flight(tp) == 0)
tcp_ca_event(sk, CA_EVENT_TX_START);
#ifdef CONFIG_TCP_MD5SIG
/*
* Are we doing MD5 on this segment? If so - make
* room for it.
*/
md5 = tp->af_specific->md5_lookup(sk, sk);
if (md5)
tcp_header_size += TCPOLEN_MD5SIG_ALIGNED;
#endif
th = (struct tcphdr *) skb_push(skb, tcp_header_size);
skb->h.th = th;
@ -460,13 +501,34 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
(sysctl_flags & SYSCTL_FLAG_WSCALE),
tp->rx_opt.rcv_wscale,
tcb->when,
tp->rx_opt.ts_recent);
tp->rx_opt.ts_recent,
#ifdef CONFIG_TCP_MD5SIG
md5 ? &md5_hash_location :
#endif
NULL);
} else {
tcp_build_and_update_options((__be32 *)(th + 1),
tp, tcb->when);
tp, tcb->when,
#ifdef CONFIG_TCP_MD5SIG
md5 ? &md5_hash_location :
#endif
NULL);
TCP_ECN_send(sk, tp, skb, tcp_header_size);
}
#ifdef CONFIG_TCP_MD5SIG
/* Calculate the MD5 hash, as we have all we need now */
if (md5) {
tp->af_specific->calc_md5_hash(md5_hash_location,
md5,
sk, NULL, NULL,
skb->h.th,
sk->sk_protocol,
skb->len);
}
#endif
icsk->icsk_af_ops->send_check(sk, skb->len, skb);
if (likely(tcb->flags & TCPCB_FLAG_ACK))
@ -840,6 +902,11 @@ unsigned int tcp_current_mss(struct sock *sk, int large_allowed)
mss_now -= (TCPOLEN_SACK_BASE_ALIGNED +
(tp->rx_opt.eff_sacks * TCPOLEN_SACK_PERBLOCK));
#ifdef CONFIG_TCP_MD5SIG
if (tp->af_specific->md5_lookup(sk, sk))
mss_now -= TCPOLEN_MD5SIG_ALIGNED;
#endif
xmit_size_goal = mss_now;
if (doing_tso) {
@ -2033,6 +2100,10 @@ struct sk_buff * tcp_make_synack(struct sock *sk, struct dst_entry *dst,
struct tcphdr *th;
int tcp_header_size;
struct sk_buff *skb;
#ifdef CONFIG_TCP_MD5SIG
struct tcp_md5sig_key *md5;
__u8 *md5_hash_location;
#endif
skb = sock_wmalloc(sk, MAX_TCP_HEADER + 15, 1, GFP_ATOMIC);
if (skb == NULL)
@ -2048,6 +2119,13 @@ struct sk_buff * tcp_make_synack(struct sock *sk, struct dst_entry *dst,
(ireq->wscale_ok ? TCPOLEN_WSCALE_ALIGNED : 0) +
/* SACK_PERM is in the place of NOP NOP of TS */
((ireq->sack_ok && !ireq->tstamp_ok) ? TCPOLEN_SACKPERM_ALIGNED : 0));
#ifdef CONFIG_TCP_MD5SIG
/* Are we doing MD5 on this segment? If so - make room for it */
md5 = tcp_rsk(req)->af_specific->md5_lookup(sk, req);
if (md5)
tcp_header_size += TCPOLEN_MD5SIG_ALIGNED;
#endif
skb->h.th = th = (struct tcphdr *) skb_push(skb, tcp_header_size);
memset(th, 0, sizeof(struct tcphdr));
@ -2085,11 +2163,29 @@ struct sk_buff * tcp_make_synack(struct sock *sk, struct dst_entry *dst,
tcp_syn_build_options((__be32 *)(th + 1), dst_metric(dst, RTAX_ADVMSS), ireq->tstamp_ok,
ireq->sack_ok, ireq->wscale_ok, ireq->rcv_wscale,
TCP_SKB_CB(skb)->when,
req->ts_recent);
req->ts_recent,
(
#ifdef CONFIG_TCP_MD5SIG
md5 ? &md5_hash_location :
#endif
NULL)
);
skb->csum = 0;
th->doff = (tcp_header_size >> 2);
TCP_INC_STATS(TCP_MIB_OUTSEGS);
#ifdef CONFIG_TCP_MD5SIG
/* Okay, we have all we need - do the md5 hash if needed */
if (md5) {
tp->af_specific->calc_md5_hash(md5_hash_location,
md5,
NULL, dst, req,
skb->h.th, sk->sk_protocol,
skb->len);
}
#endif
return skb;
}
@ -2108,6 +2204,11 @@ static void tcp_connect_init(struct sock *sk)
tp->tcp_header_len = sizeof(struct tcphdr) +
(sysctl_tcp_timestamps ? TCPOLEN_TSTAMP_ALIGNED : 0);
#ifdef CONFIG_TCP_MD5SIG
if (tp->af_specific->md5_lookup(sk, sk) != NULL)
tp->tcp_header_len += TCPOLEN_MD5SIG_ALIGNED;
#endif
/* If user gave his TCP_MAXSEG, record it to clamp */
if (tp->rx_opt.user_mss)
tp->rx_opt.mss_clamp = tp->rx_opt.user_mss;

568
net/ipv6/tcp_ipv6.c
Просмотреть файл

@ -66,10 +66,13 @@
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/crypto.h>
#include <linux/scatterlist.h>
/* Socket used for sending RSTs and ACKs */
static struct socket *tcp6_socket;
static void tcp_v6_send_reset(struct sk_buff *skb);
static void tcp_v6_send_reset(struct sock *sk, struct sk_buff *skb);
static void tcp_v6_reqsk_send_ack(struct sk_buff *skb, struct request_sock *req);
static void tcp_v6_send_check(struct sock *sk, int len,
struct sk_buff *skb);
@ -78,6 +81,8 @@ static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb);
static struct inet_connection_sock_af_ops ipv6_mapped;
static struct inet_connection_sock_af_ops ipv6_specific;
static struct tcp_sock_af_ops tcp_sock_ipv6_specific;
static struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific;
static int tcp_v6_get_port(struct sock *sk, unsigned short snum)
{
@ -208,6 +213,9 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
icsk->icsk_af_ops = &ipv6_mapped;
sk->sk_backlog_rcv = tcp_v4_do_rcv;
#ifdef CONFIG_TCP_MD5SIG
tp->af_specific = &tcp_sock_ipv6_mapped_specific;
#endif
err = tcp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin));
@ -215,6 +223,9 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
icsk->icsk_ext_hdr_len = exthdrlen;
icsk->icsk_af_ops = &ipv6_specific;
sk->sk_backlog_rcv = tcp_v6_do_rcv;
#ifdef CONFIG_TCP_MD5SIG
tp->af_specific = &tcp_sock_ipv6_specific;
#endif
goto failure;
} else {
ipv6_addr_set(&np->saddr, 0, 0, htonl(0x0000FFFF),
@ -518,6 +529,396 @@ static void tcp_v6_reqsk_destructor(struct request_sock *req)
kfree_skb(inet6_rsk(req)->pktopts);
}
#ifdef CONFIG_TCP_MD5SIG
static struct tcp_md5sig_key *tcp_v6_md5_do_lookup(struct sock *sk,
struct in6_addr *addr)
{
struct tcp_sock *tp = tcp_sk(sk);
int i;
BUG_ON(tp == NULL);
if (!tp->md5sig_info || !tp->md5sig_info->entries6)
return NULL;
for (i = 0; i < tp->md5sig_info->entries6; i++) {
if (ipv6_addr_cmp(&tp->md5sig_info->keys6[i].addr, addr) == 0)
return (struct tcp_md5sig_key *)&tp->md5sig_info->keys6[i];
}
return NULL;
}
static struct tcp_md5sig_key *tcp_v6_md5_lookup(struct sock *sk,
struct sock *addr_sk)
{
return tcp_v6_md5_do_lookup(sk, &inet6_sk(addr_sk)->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, &inet6_rsk(req)->rmt_addr);
}
static int tcp_v6_md5_do_add(struct sock *sk, struct in6_addr *peer,
char *newkey, u8 newkeylen)
{
/* Add key to the list */
struct tcp6_md5sig_key *key;
struct tcp_sock *tp = tcp_sk(sk);
struct tcp6_md5sig_key *keys;
key = (struct tcp6_md5sig_key*) tcp_v6_md5_do_lookup(sk, peer);
if (key) {
/* modify existing entry - just update that one */
kfree(key->key);
key->key = newkey;
key->keylen = newkeylen;
} else {
/* reallocate new list if current one is full. */
if (!tp->md5sig_info) {
tp->md5sig_info = kzalloc(sizeof(*tp->md5sig_info), GFP_ATOMIC);
if (!tp->md5sig_info) {
kfree(newkey);
return -ENOMEM;
}
}
tcp_alloc_md5sig_pool();
if (tp->md5sig_info->alloced6 == tp->md5sig_info->entries6) {
keys = kmalloc((sizeof (tp->md5sig_info->keys6[0]) *
(tp->md5sig_info->entries6 + 1)), GFP_ATOMIC);
if (!keys) {
tcp_free_md5sig_pool();
kfree(newkey);
return -ENOMEM;
}
if (tp->md5sig_info->entries6)
memmove(keys, tp->md5sig_info->keys6,
(sizeof (tp->md5sig_info->keys6[0]) *
tp->md5sig_info->entries6));
kfree(tp->md5sig_info->keys6);
tp->md5sig_info->keys6 = keys;
tp->md5sig_info->alloced6++;
}
ipv6_addr_copy(&tp->md5sig_info->keys6[tp->md5sig_info->entries6].addr,
peer);
tp->md5sig_info->keys6[tp->md5sig_info->entries6].key = newkey;
tp->md5sig_info->keys6[tp->md5sig_info->entries6].keylen = newkeylen;
tp->md5sig_info->entries6++;
}
return 0;
}
static int tcp_v6_md5_add_func(struct sock *sk, struct sock *addr_sk,
u8 *newkey, __u8 newkeylen)
{
return tcp_v6_md5_do_add(sk, &inet6_sk(addr_sk)->daddr,
newkey, newkeylen);
}
static int tcp_v6_md5_do_del(struct sock *sk, struct in6_addr *peer)
{
struct tcp_sock *tp = tcp_sk(sk);
int i;
for (i = 0; i < tp->md5sig_info->entries6; i++) {
if (ipv6_addr_cmp(&tp->md5sig_info->keys6[i].addr, peer) == 0) {
/* Free the key */
kfree(tp->md5sig_info->keys6[i].key);
tp->md5sig_info->entries6--;
if (tp->md5sig_info->entries6 == 0) {
kfree(tp->md5sig_info->keys6);
tp->md5sig_info->keys6 = NULL;
tcp_free_md5sig_pool();
return 0;
} else {
/* shrink the database */
if (tp->md5sig_info->entries6 != i)
memmove(&tp->md5sig_info->keys6[i],
&tp->md5sig_info->keys6[i+1],
(tp->md5sig_info->entries6 - i)
* sizeof (tp->md5sig_info->keys6[0]));
}
}
}
return -ENOENT;
}
static void tcp_v6_clear_md5_list (struct sock *sk)
{
struct tcp_sock *tp = tcp_sk(sk);
int i;
if (tp->md5sig_info->entries6) {
for (i = 0; i < tp->md5sig_info->entries6; i++)
kfree(tp->md5sig_info->keys6[i].key);
tp->md5sig_info->entries6 = 0;
tcp_free_md5sig_pool();
}
kfree(tp->md5sig_info->keys6);
tp->md5sig_info->keys6 = NULL;
tp->md5sig_info->alloced6 = 0;
if (tp->md5sig_info->entries4) {
for (i = 0; i < tp->md5sig_info->entries4; i++)
kfree(tp->md5sig_info->keys4[i].key);
tp->md5sig_info->entries4 = 0;
tcp_free_md5sig_pool();
}
kfree(tp->md5sig_info->keys4);
tp->md5sig_info->keys4 = NULL;
tp->md5sig_info->alloced4 = 0;
}
static int tcp_v6_parse_md5_keys (struct sock *sk, char __user *optval,
int optlen)
{
struct tcp_md5sig cmd;
struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&cmd.tcpm_addr;
u8 *newkey;
if (optlen < sizeof(cmd))
return -EINVAL;
if (copy_from_user(&cmd, optval, sizeof(cmd)))
return -EFAULT;
if (sin6->sin6_family != AF_INET6)
return -EINVAL;
if (!cmd.tcpm_keylen) {
if (!tcp_sk(sk)->md5sig_info)
return -ENOENT;
if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_MAPPED)
return tcp_v4_md5_do_del(sk, sin6->sin6_addr.s6_addr32[3]);
return tcp_v6_md5_do_del(sk, &sin6->sin6_addr);
}
if (cmd.tcpm_keylen > TCP_MD5SIG_MAXKEYLEN)
return -EINVAL;
if (!tcp_sk(sk)->md5sig_info) {
struct tcp_sock *tp = tcp_sk(sk);
struct tcp_md5sig_info *p;
p = kzalloc(sizeof(struct tcp_md5sig_info), GFP_KERNEL);
if (!p)
return -ENOMEM;
tp->md5sig_info = p;
}
newkey = kmalloc(cmd.tcpm_keylen, GFP_KERNEL);
if (!newkey)
return -ENOMEM;
memcpy(newkey, cmd.tcpm_key, cmd.tcpm_keylen);
if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_MAPPED) {
return tcp_v4_md5_do_add(sk, sin6->sin6_addr.s6_addr32[3],
newkey, cmd.tcpm_keylen);
}
return tcp_v6_md5_do_add(sk, &sin6->sin6_addr, newkey, cmd.tcpm_keylen);
}
static int tcp_v6_do_calc_md5_hash(char *md5_hash, struct tcp_md5sig_key *key,
struct in6_addr *saddr,
struct in6_addr *daddr,
struct tcphdr *th, int protocol,
int tcplen)
{
struct scatterlist sg[4];
__u16 data_len;
int block = 0;
__u16 cksum;
struct tcp_md5sig_pool *hp;
struct tcp6_pseudohdr *bp;
struct hash_desc *desc;
int err;
unsigned int nbytes = 0;
hp = tcp_get_md5sig_pool();
if (!hp) {
printk(KERN_WARNING "%s(): hash pool not found...\n", __FUNCTION__);
goto clear_hash_noput;
}
bp = &hp->md5_blk.ip6;
desc = &hp->md5_desc;
/* 1. TCP pseudo-header (RFC2460) */
ipv6_addr_copy(&bp->saddr, saddr);
ipv6_addr_copy(&bp->daddr, daddr);
bp->len = htonl(tcplen);
bp->protocol = htonl(protocol);
sg_set_buf(&sg[block++], bp, sizeof(*bp));
nbytes += sizeof(*bp);
/* 2. TCP header, excluding options */
cksum = th->check;
th->check = 0;
sg_set_buf(&sg[block++], th, sizeof(*th));
nbytes += sizeof(*th);
/* 3. TCP segment data (if any) */
data_len = tcplen - (th->doff << 2);
if (data_len > 0) {
u8 *data = (u8 *)th + (th->doff << 2);
sg_set_buf(&sg[block++], data, data_len);
nbytes += data_len;
}
/* 4. shared key */
sg_set_buf(&sg[block++], key->key, key->keylen);
nbytes += key->keylen;
/* Now store the hash into the packet */
err = crypto_hash_init(desc);
if (err) {
printk(KERN_WARNING "%s(): hash_init failed\n", __FUNCTION__);
goto clear_hash;
}
err = crypto_hash_update(desc, sg, nbytes);
if (err) {
printk(KERN_WARNING "%s(): hash_update failed\n", __FUNCTION__);
goto clear_hash;
}
err = crypto_hash_final(desc, md5_hash);
if (err) {
printk(KERN_WARNING "%s(): hash_final failed\n", __FUNCTION__);
goto clear_hash;
}
/* Reset header, and free up the crypto */
tcp_put_md5sig_pool();
th->check = cksum;
out:
return 0;
clear_hash:
tcp_put_md5sig_pool();
clear_hash_noput:
memset(md5_hash, 0, 16);
goto out;
}
static int tcp_v6_calc_md5_hash(char *md5_hash, struct tcp_md5sig_key *key,
struct sock *sk,
struct dst_entry *dst,
struct request_sock *req,
struct tcphdr *th, int protocol,
int tcplen)
{
struct in6_addr *saddr, *daddr;
if (sk) {
saddr = &inet6_sk(sk)->saddr;
daddr = &inet6_sk(sk)->daddr;
} else {
saddr = &inet6_rsk(req)->loc_addr;
daddr = &inet6_rsk(req)->rmt_addr;
}
return tcp_v6_do_calc_md5_hash(md5_hash, key,
saddr, daddr,
th, protocol, tcplen);
}
static int tcp_v6_inbound_md5_hash (struct sock *sk, struct sk_buff *skb)
{
__u8 *hash_location = NULL;
struct tcp_md5sig_key *hash_expected;
struct ipv6hdr *ip6h = skb->nh.ipv6h;
struct tcphdr *th = skb->h.th;
int length = (th->doff << 2) - sizeof (*th);
int genhash;
u8 *ptr;
u8 newhash[16];
hash_expected = tcp_v6_md5_do_lookup(sk, &ip6h->saddr);
/* If the TCP option is too short, we can short cut */
if (length < TCPOLEN_MD5SIG)
return hash_expected ? 1 : 0;
/* parse options */
ptr = (u8*)(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 || opsize > length)
goto done_opts;
if (opcode == TCPOPT_MD5SIG) {
hash_location = ptr;
goto done_opts;
}
}
ptr += opsize - 2;
length -= opsize;
}
done_opts:
/* do we have a hash as expected? */
if (!hash_expected) {
if (!hash_location)
return 0;
if (net_ratelimit()) {
printk(KERN_INFO "MD5 Hash NOT expected but found "
"(" NIP6_FMT ", %u)->"
"(" NIP6_FMT ", %u)\n",
NIP6(ip6h->saddr), ntohs(th->source),
NIP6(ip6h->daddr), ntohs(th->dest));
}
return 1;
}
if (!hash_location) {
if (net_ratelimit()) {
printk(KERN_INFO "MD5 Hash expected but NOT found "
"(" NIP6_FMT ", %u)->"
"(" NIP6_FMT ", %u)\n",
NIP6(ip6h->saddr), ntohs(th->source),
NIP6(ip6h->daddr), ntohs(th->dest));
}
return 1;
}
/* check the signature */
genhash = tcp_v6_do_calc_md5_hash(newhash,
hash_expected,
&ip6h->saddr, &ip6h->daddr,
th, sk->sk_protocol,
skb->len);
if (genhash || memcmp(hash_location, newhash, 16) != 0) {
if (net_ratelimit()) {
printk(KERN_INFO "MD5 Hash %s for "
"(" NIP6_FMT ", %u)->"
"(" NIP6_FMT ", %u)\n",
genhash ? "failed" : "mismatch",
NIP6(ip6h->saddr), ntohs(th->source),
NIP6(ip6h->daddr), ntohs(th->dest));
}
return 1;
}
return 0;
}
#endif
static struct request_sock_ops tcp6_request_sock_ops __read_mostly = {
.family = AF_INET6,
.obj_size = sizeof(struct tcp6_request_sock),
@ -527,9 +928,16 @@ static struct request_sock_ops tcp6_request_sock_ops __read_mostly = {
.send_reset = tcp_v6_send_reset
};
struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = {
#ifdef CONFIG_TCP_MD5SIG
.md5_lookup = tcp_v6_reqsk_md5_lookup,
#endif
};
static struct timewait_sock_ops tcp6_timewait_sock_ops = {
.twsk_obj_size = sizeof(struct tcp6_timewait_sock),
.twsk_unique = tcp_twsk_unique,
.twsk_destructor= tcp_twsk_destructor,
};
static void tcp_v6_send_check(struct sock *sk, int len, struct sk_buff *skb)
@ -566,11 +974,15 @@ static int tcp_v6_gso_send_check(struct sk_buff *skb)
return 0;
}
static void tcp_v6_send_reset(struct sk_buff *skb)
static void tcp_v6_send_reset(struct sock *sk, struct sk_buff *skb)
{
struct tcphdr *th = skb->h.th, *t1;
struct sk_buff *buff;
struct flowi fl;
int tot_len = sizeof(*th);
#ifdef CONFIG_TCP_MD5SIG
struct tcp_md5sig_key *key;
#endif
if (th->rst)
return;
@ -578,25 +990,35 @@ static void tcp_v6_send_reset(struct sk_buff *skb)
if (!ipv6_unicast_destination(skb))
return;
#ifdef CONFIG_TCP_MD5SIG
if (sk)
key = tcp_v6_md5_do_lookup(sk, &skb->nh.ipv6h->daddr);
else
key = NULL;
if (key)
tot_len += TCPOLEN_MD5SIG_ALIGNED;
#endif
/*
* We need to grab some memory, and put together an RST,
* and then put it into the queue to be sent.
*/
buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + sizeof(struct tcphdr),
buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + tot_len,
GFP_ATOMIC);
if (buff == NULL)
return;
skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr) + sizeof(struct tcphdr));
skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr) + tot_len);
t1 = (struct tcphdr *) skb_push(buff,sizeof(struct tcphdr));
t1 = (struct tcphdr *) skb_push(buff, tot_len);
/* Swap the send and the receive. */
memset(t1, 0, sizeof(*t1));
t1->dest = th->source;
t1->source = th->dest;
t1->doff = sizeof(*t1)/4;
t1->doff = tot_len / 4;
t1->rst = 1;
if(th->ack) {
@ -607,6 +1029,22 @@ static void tcp_v6_send_reset(struct sk_buff *skb)
+ skb->len - (th->doff<<2));
}
#ifdef CONFIG_TCP_MD5SIG
if (key) {
u32 *opt = (u32*)(t1 + 1);
opt[0] = htonl((TCPOPT_NOP << 24) |
(TCPOPT_NOP << 16) |
(TCPOPT_MD5SIG << 8) |
TCPOLEN_MD5SIG);
tcp_v6_do_calc_md5_hash((__u8*)&opt[1],
key,
&skb->nh.ipv6h->daddr,
&skb->nh.ipv6h->saddr,
t1, IPPROTO_TCP,
tot_len);
}
#endif
buff->csum = csum_partial((char *)t1, sizeof(*t1), 0);
memset(&fl, 0, sizeof(fl));
@ -637,15 +1075,37 @@ static void tcp_v6_send_reset(struct sk_buff *skb)
kfree_skb(buff);
}
static void tcp_v6_send_ack(struct sk_buff *skb, u32 seq, u32 ack, u32 win, u32 ts)
static void tcp_v6_send_ack(struct tcp_timewait_sock *tw,
struct sk_buff *skb, u32 seq, u32 ack, u32 win, u32 ts)
{
struct tcphdr *th = skb->h.th, *t1;
struct sk_buff *buff;
struct flowi fl;
int tot_len = sizeof(struct tcphdr);
u32 *topt;
#ifdef CONFIG_TCP_MD5SIG
struct tcp_md5sig_key *key;
struct tcp_md5sig_key tw_key;
#endif
#ifdef CONFIG_TCP_MD5SIG
if (!tw && skb->sk) {
key = tcp_v6_md5_do_lookup(skb->sk, &skb->nh.ipv6h->daddr);
} else if (tw && tw->tw_md5_keylen) {
tw_key.key = tw->tw_md5_key;
tw_key.keylen = tw->tw_md5_keylen;
key = &tw_key;
} else {
key = NULL;
}
#endif
if (ts)
tot_len += TCPOLEN_TSTAMP_ALIGNED;
#ifdef CONFIG_TCP_MD5SIG
if (key)
tot_len += TCPOLEN_MD5SIG_ALIGNED;
#endif
buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + tot_len,
GFP_ATOMIC);
@ -665,15 +1125,29 @@ static void tcp_v6_send_ack(struct sk_buff *skb, u32 seq, u32 ack, u32 win, u32
t1->ack_seq = htonl(ack);
t1->ack = 1;
t1->window = htons(win);
topt = (u32*)(t1 + 1);
if (ts) {
u32 *ptr = (u32*)(t1 + 1);
*ptr++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) |
(TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP);
*ptr++ = htonl(tcp_time_stamp);
*ptr = htonl(ts);
*topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) |
(TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP);
*topt++ = htonl(tcp_time_stamp);
*topt = htonl(ts);
}
#ifdef CONFIG_TCP_MD5SIG
if (key) {
*topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) |
(TCPOPT_MD5SIG << 8) | TCPOLEN_MD5SIG);
tcp_v6_do_calc_md5_hash((__u8 *)topt,
key,
&skb->nh.ipv6h->daddr,
&skb->nh.ipv6h->saddr,
t1, IPPROTO_TCP,
tot_len);
}
#endif
buff->csum = csum_partial((char *)t1, tot_len, 0);
memset(&fl, 0, sizeof(fl));
@ -704,9 +1178,9 @@ static void tcp_v6_send_ack(struct sk_buff *skb, u32 seq, u32 ack, u32 win, u32
static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb)
{
struct inet_timewait_sock *tw = inet_twsk(sk);
const struct tcp_timewait_sock *tcptw = tcp_twsk(sk);
struct tcp_timewait_sock *tcptw = tcp_twsk(sk);
tcp_v6_send_ack(skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt,
tcp_v6_send_ack(tcptw, skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt,
tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale,
tcptw->tw_ts_recent);
@ -715,7 +1189,7 @@ static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb)
static void tcp_v6_reqsk_send_ack(struct sk_buff *skb, struct request_sock *req)
{
tcp_v6_send_ack(skb, tcp_rsk(req)->snt_isn + 1, tcp_rsk(req)->rcv_isn + 1, req->rcv_wnd, req->ts_recent);
tcp_v6_send_ack(NULL, skb, tcp_rsk(req)->snt_isn + 1, tcp_rsk(req)->rcv_isn + 1, req->rcv_wnd, req->ts_recent);
}
@ -786,6 +1260,10 @@ static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
if (req == NULL)
goto drop;
#ifdef CONFIG_TCP_MD5SIG
tcp_rsk(req)->af_specific = &tcp_request_sock_ipv6_ops;
#endif
tcp_clear_options(&tmp_opt);
tmp_opt.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr);
tmp_opt.user_mss = tp->rx_opt.user_mss;
@ -844,6 +1322,9 @@ static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
struct tcp_sock *newtp;
struct sock *newsk;
struct ipv6_txoptions *opt;
#ifdef CONFIG_TCP_MD5SIG
struct tcp_md5sig_key *key;
#endif
if (skb->protocol == htons(ETH_P_IP)) {
/*
@ -874,6 +1355,10 @@ static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
inet_csk(newsk)->icsk_af_ops = &ipv6_mapped;
newsk->sk_backlog_rcv = tcp_v4_do_rcv;
#ifdef CONFIG_TCP_MD5SIG
newtp->af_specific = &tcp_sock_ipv6_mapped_specific;
#endif
newnp->pktoptions = NULL;
newnp->opt = NULL;
newnp->mcast_oif = inet6_iif(skb);
@ -1008,6 +1493,23 @@ static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
newinet->daddr = newinet->saddr = newinet->rcv_saddr = LOOPBACK4_IPV6;
#ifdef CONFIG_TCP_MD5SIG
/* Copy over the MD5 key from the original socket */
if ((key = tcp_v6_md5_do_lookup(sk, &newnp->daddr)) != NULL) {
/* We're using one, so create a matching key
* on the newsk structure. If we fail to get
* memory, then we end up not copying the key
* across. Shucks.
*/
char *newkey = kmalloc(key->keylen, GFP_ATOMIC);
if (newkey) {
memcpy(newkey, key->key, key->keylen);
tcp_v6_md5_do_add(newsk, &inet6_sk(sk)->daddr,
newkey, key->keylen);
}
}
#endif
__inet6_hash(&tcp_hashinfo, newsk);
inet_inherit_port(&tcp_hashinfo, sk, newsk);
@ -1067,6 +1569,11 @@ static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
if (skb->protocol == htons(ETH_P_IP))
return tcp_v4_do_rcv(sk, skb);
#ifdef CONFIG_TCP_MD5SIG
if (tcp_v6_inbound_md5_hash (sk, skb))
goto discard;
#endif
if (sk_filter(sk, skb))
goto discard;
@ -1132,7 +1639,7 @@ static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
return 0;
reset:
tcp_v6_send_reset(skb);
tcp_v6_send_reset(sk, skb);
discard:
if (opt_skb)
__kfree_skb(opt_skb);
@ -1257,7 +1764,7 @@ no_tcp_socket:
bad_packet:
TCP_INC_STATS_BH(TCP_MIB_INERRS);
} else {
tcp_v6_send_reset(skb);
tcp_v6_send_reset(NULL, skb);
}
discard_it:
@ -1336,6 +1843,15 @@ static struct inet_connection_sock_af_ops ipv6_specific = {
#endif
};
static struct tcp_sock_af_ops tcp_sock_ipv6_specific = {
#ifdef CONFIG_TCP_MD5SIG
.md5_lookup = tcp_v6_md5_lookup,
.calc_md5_hash = tcp_v6_calc_md5_hash,
.md5_add = tcp_v6_md5_add_func,
.md5_parse = tcp_v6_parse_md5_keys,
#endif
};
/*
* TCP over IPv4 via INET6 API
*/
@ -1358,6 +1874,15 @@ static struct inet_connection_sock_af_ops ipv6_mapped = {
#endif
};
static struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific = {
#ifdef CONFIG_TCP_MD5SIG
.md5_lookup = tcp_v4_md5_lookup,
.calc_md5_hash = tcp_v4_calc_md5_hash,
.md5_add = tcp_v6_md5_add_func,
.md5_parse = tcp_v6_parse_md5_keys,
#endif
};
/* NOTE: A lot of things set to zero explicitly by call to
* sk_alloc() so need not be done here.
*/
@ -1397,6 +1922,10 @@ static int tcp_v6_init_sock(struct sock *sk)
sk->sk_write_space = sk_stream_write_space;
sock_set_flag(sk, SOCK_USE_WRITE_QUEUE);
#ifdef CONFIG_TCP_MD5SIG
tp->af_specific = &tcp_sock_ipv6_specific;
#endif
sk->sk_sndbuf = sysctl_tcp_wmem[1];
sk->sk_rcvbuf = sysctl_tcp_rmem[1];
@ -1407,6 +1936,11 @@ static int tcp_v6_init_sock(struct sock *sk)
static int tcp_v6_destroy_sock(struct sock *sk)
{
#ifdef CONFIG_TCP_MD5SIG
/* Clean up the MD5 key list */
if (tcp_sk(sk)->md5sig_info)
tcp_v6_clear_md5_list(sk);
#endif
tcp_v4_destroy_sock(sk);
return inet6_destroy_sock(sk);
}