Commit 822c8685 authored by Deepa Dinamani's avatar Deepa Dinamani Committed by David S. Miller
Browse files

net: ipv4: Convert IP network timestamps to be y2038 safe 



ICMP timestamp messages and IP source route options require
timestamps to be in milliseconds modulo 24 hours from
midnight UT format.

Add inet_current_timestamp() function to support this. The function
returns the required timestamp in network byte order.

Timestamp calculation is also changed to call ktime_get_real_ts64()
which uses struct timespec64. struct timespec64 is y2038 safe.
Previously it called getnstimeofday() which uses struct timespec.
struct timespec is not y2038 safe.

Signed-off-by: default avatarDeepa Dinamani <deepa.kernel@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: James Morris <jmorris@namei.org>
Cc: Patrick McHardy <kaber@trash.net>
Acked-by: default avatarYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Acked-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent e9c0d61d

include/net/ip.h

+2 −0
Original line number Diff line number Diff line
@@ -240,6 +240,8 @@ static inline int inet_is_local_reserved_port(struct net *net, int port) 
}

#endif



__be32 inet_current_timestamp(void);



/* From inetpeer.c */

extern int inet_peer_threshold;

extern int inet_peer_minttl;

net/ipv4/af_inet.c

+26 −0
Original line number Diff line number Diff line
@@ -1380,6 +1380,32 @@ out: 
	return pp;

}



#define SECONDS_PER_DAY	86400



/* inet_current_timestamp - Return IP network timestamp

 *

 * Return milliseconds since midnight in network byte order.

 */

__be32 inet_current_timestamp(void)

{

	u32 secs;

	u32 msecs;

	struct timespec64 ts;



	ktime_get_real_ts64(&ts);



	/* Get secs since midnight. */

	(void)div_u64_rem(ts.tv_sec, SECONDS_PER_DAY, &secs);

	/* Convert to msecs. */

	msecs = secs * MSEC_PER_SEC;

	/* Convert nsec to msec. */

	msecs += (u32)ts.tv_nsec / NSEC_PER_MSEC;



	/* Convert to network byte order. */

	return htons(msecs);

}

EXPORT_SYMBOL(inet_current_timestamp);



int inet_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)

{

	if (sk->sk_family == AF_INET)

net/ipv4/icmp.c

+1 −4
Original line number Diff line number Diff line
@@ -931,7 +931,6 @@ static bool icmp_echo(struct sk_buff *skb) 
 */

static bool icmp_timestamp(struct sk_buff *skb)

{

	struct timespec tv;

	struct icmp_bxm icmp_param;

	/*

	 *	Too short.
@@ -942,9 +941,7 @@ static bool icmp_timestamp(struct sk_buff *skb) 
	/*

	 *	Fill in the current time as ms since midnight UT:

	 */

	getnstimeofday(&tv);

	icmp_param.data.times[1] = htonl((tv.tv_sec % 86400) * MSEC_PER_SEC +

					 tv.tv_nsec / NSEC_PER_MSEC);

	icmp_param.data.times[1] = inet_current_timestamp();

	icmp_param.data.times[2] = icmp_param.data.times[1];

	if (skb_copy_bits(skb, 0, &icmp_param.data.times[0], 4))

		BUG();

net/ipv4/ip_options.c

+6 −8
Original line number Diff line number Diff line
@@ -58,10 +58,9 @@ void ip_options_build(struct sk_buff *skb, struct ip_options *opt, 
		if (opt->ts_needaddr)

			ip_rt_get_source(iph+opt->ts+iph[opt->ts+2]-9, skb, rt);

		if (opt->ts_needtime) {

			struct timespec tv;

			__be32 midtime;

			getnstimeofday(&tv);

			midtime = htonl((tv.tv_sec % 86400) * MSEC_PER_SEC + tv.tv_nsec / NSEC_PER_MSEC);



			midtime = inet_current_timestamp();

			memcpy(iph+opt->ts+iph[opt->ts+2]-5, &midtime, 4);

		}

		return;
@@ -415,11 +414,10 @@ int ip_options_compile(struct net *net, 
					break;

				}

				if (timeptr) {

					struct timespec tv;

					u32  midtime;

					getnstimeofday(&tv);

					midtime = (tv.tv_sec % 86400) * MSEC_PER_SEC + tv.tv_nsec / NSEC_PER_MSEC;

					put_unaligned_be32(midtime, timeptr);

					__be32 midtime;



					midtime = inet_current_timestamp();

					memcpy(timeptr, &midtime, 4);

					opt->is_changed = 1;

				}

			} else if ((optptr[3]&0xF) != IPOPT_TS_PRESPEC) {

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