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: Deepa Dinamani <deepa.ker...@gmail.com>
Cc: "David S. Miller" <da...@davemloft.net>
Cc: Alexey Kuznetsov <kuz...@ms2.inr.ac.ru>
Cc: Hideaki YOSHIFUJI <yoshf...@linux-ipv6.org>
Cc: James Morris <jmor...@namei.org>
Cc: Patrick McHardy <ka...@trash.net>
---
include/net/ip.h | 2 ++
net/ipv4/af_inet.c | 26 ++++++++++++++++++++++++++
net/ipv4/icmp.c | 5 +----
net/ipv4/ip_options.c | 14 ++++++--------
4 files changed, 35 insertions(+), 12 deletions(-)
diff --git a/include/net/ip.h b/include/net/ip.h
index 1a98f1c..5d3a9eb 100644
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -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;
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index eade66d..408e2b3 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1386,6 +1386,32 @@ 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)
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index 36e2697..6333489 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -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();
diff --git a/net/ipv4/ip_options.c b/net/ipv4/ip_options.c
index bd24679..4d158ff 100644
--- a/net/ipv4/ip_options.c
+++ b/net/ipv4/ip_options.c
@@ -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) {
--
1.9.1
