Hi Matt,
On Fri, Dec 18, 2020 at 12:06:51AM +0100, Matthieu Baerts wrote:
Hi Geliang, Mat,
On 17/12/2020 01:23, Mat Martineau wrote:
> On Wed, 16 Dec 2020, Geliang Tang wrote:
>
> > Currently, PM doesn't create subflow with IPv4-mapped IPv6 socket. This
> > patch converts the IPv4 address to IPv4-mapped IPv6 address to fix it.
> >
> > Signed-off-by: Geliang Tang <geliangtang(a)gmail.com>
> > ---
> > net/mptcp/pm_netlink.c | 25 ++++++++++++++++++++++---
> > 1 file changed, 22 insertions(+), 3 deletions(-)
> >
> > diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
> > index cc4ca013a06b..987e83cdee11 100644
> > --- a/net/mptcp/pm_netlink.c
> > +++ b/net/mptcp/pm_netlink.c
> > @@ -145,6 +158,8 @@ select_local_address(const struct pm_nl_pernet
> > *pernet,
> > if (!(entry->addr.flags & MPTCP_PM_ADDR_FLAG_SUBFLOW))
> > continue;
> >
> > + mptcp_pm_addr_convert_v4mapped(msk, &entry->addr);
> > +
>
> This is modifying the contents of pernet->local_addr_list, not a copy of
> the entry, when the msk has a v4mapped address. I'm not sure that's the
> way to fix this, and might leave some corner cases unaddressed.
>
> Did you look at modifying addresses_equal() so it can detect equivalent
> IPv4 and v4mapped addresses?
Maybe something like that the patch I joined?
I didn't try much but maybe more what we want?
Thanks for your help. Your patch is much better than mine. I added your
code in v3 with only a slightly change in addresses_equal. I added your
Co-developed-by tag in v3 if you don't mind:
@@ -66,12 +66,11 @@ static bool addresses_equal(const struct mptcp_addr_info *a,
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
else
addr_equals = !ipv6_addr_cmp(&a->addr6, &b->addr6);
- } else if (a->family == AF_INET6) {
- if (b->family == AF_INET &&
ipv6_addr_v4mapped(&a->addr6))
- addr_equals = a->addr6.s6_addr32[3] == b->addr.s_addr;
- } else if (b->family == AF_INET6) {
+ } else {
if (a->family == AF_INET &&
ipv6_addr_v4mapped(&b->addr6))
addr_equals = a->addr.s_addr == b->addr6.s6_addr32[3];
+ if (b->family == AF_INET &&
ipv6_addr_v4mapped(&a->addr6))
+ addr_equals = a->addr6.s6_addr32[3] == b->addr.s_addr;
#endif
}
And I added the following code in mptcp_info2sockaddr to deal with the
IPv4-mapped back to IPv4 case too:
--- a/net/mptcp/subflow.c
+++ b/net/mptcp/subflow.c
@@ -1082,7 +1082,10 @@ static void mptcp_info2sockaddr(const struct mptcp_addr_info
*info,
if (addr->ss_family == AF_INET) {
struct sockaddr_in *in_addr = (struct sockaddr_in *)addr;
- in_addr->sin_addr = info->addr;
+ if (info->family == AF_INET)
+ in_addr->sin_addr = info->addr;
+ else
+ in_addr->sin_addr.s_addr = info->addr6.s6_addr32[3];
in_addr->sin_port = info->port;
}
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
Also in v3 I added two new IPv4-mapped back to IPv4 testcases:
+# signal subflow v6-map-v4
+reset
+ip netns exec $ns1 ./pm_nl_ctl limits 0 1
+ip netns exec $ns2 ./pm_nl_ctl limits 0 1
+ip netns exec $ns2 ./pm_nl_ctl add "::ffff:10.0.3.2" flags subflow
+run_tests $ns1 $ns2 10.0.1.1
+chk_join_nr "single subflow v6-map-v4" 1 1 1
+
+# signal address v6-map-v4
+reset
+ip netns exec $ns1 ./pm_nl_ctl limits 0 1
+ip netns exec $ns2 ./pm_nl_ctl limits 1 1
+ip netns exec $ns1 ./pm_nl_ctl add "::ffff:10.0.2.1" flags signal
+run_tests $ns1 $ns2 10.0.1.1
+chk_join_nr "signal address v6-map-v4" 1 1 1
+chk_add_nr 1 1
Thanks.
-Geliang
Cheers,
Matt
--
Tessares | Belgium | Hybrid Access Solutions
www.tessares.net
>From 36f5e1f9bade5329e82a85fb6330db57a165c04c Mon Sep 17 00:00:00
2001
From: Matthieu Baerts <matthieu.baerts(a)tessares.net>
Date: Fri, 18 Dec 2020 00:03:12 +0100
Subject: [PATCH] mptcp: support v4mappedv6
Signed-off-by: Matthieu Baerts <matthieu.baerts(a)tessares.net>
---
net/mptcp/pm_netlink.c | 22 +++++++++++++---------
net/mptcp/subflow.c | 17 +++++++++++------
2 files changed, 24 insertions(+), 15 deletions(-)
diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index 9b1f6298bbdb..6c89a9e0099b 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -60,15 +60,20 @@ static bool addresses_equal(const struct mptcp_addr_info *a,
{
bool addr_equals = false;
- if (a->family != b->family)
- return false;
-
- if (a->family == AF_INET)
- addr_equals = a->addr.s_addr == b->addr.s_addr;
+ if (a->family == b->family) {
+ if (a->family == AF_INET)
+ addr_equals = a->addr.s_addr == b->addr.s_addr;
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
- else
- addr_equals = !ipv6_addr_cmp(&a->addr6, &b->addr6);
+ else
+ addr_equals = !ipv6_addr_cmp(&a->addr6, &b->addr6);
+ } else if (a->family == AF_INET6) {
+ if (b->family == AF_INET && ipv6_addr_v4mapped(&a->addr6))
+ addr_equals = a->addr6.s6_addr32[3] == b->addr.s_addr;
+ } else if (b->family == AF_INET6) {
+ if (a->family == AF_INET && ipv6_addr_v4mapped(&b->addr6))
+ addr_equals = a->addr.s_addr == b->addr6.s6_addr32[3];
#endif
+ }
if (!addr_equals)
return false;
@@ -147,8 +152,7 @@ select_local_address(const struct pm_nl_pernet *pernet,
/* avoid any address already in use by subflows and
* pending join
*/
- if (entry->addr.family == ((struct sock *)msk)->sk_family &&
- !lookup_subflow_by_saddr(&msk->conn_list, &entry->addr)) {
+ if (!lookup_subflow_by_saddr(&msk->conn_list, &entry->addr)) {
ret = entry;
break;
}
diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c
index 278cbe3e539e..11cc0ef3ae3c 100644
--- a/net/mptcp/subflow.c
+++ b/net/mptcp/subflow.c
@@ -1074,10 +1074,11 @@ void mptcpv6_handle_mapped(struct sock *sk, bool mapped)
#endif
static void mptcp_info2sockaddr(const struct mptcp_addr_info *info,
- struct sockaddr_storage *addr)
+ struct sockaddr_storage *addr,
+ unsigned short family)
{
memset(addr, 0, sizeof(*addr));
- addr->ss_family = info->family;
+ addr->ss_family = family;
if (addr->ss_family == AF_INET) {
struct sockaddr_in *in_addr = (struct sockaddr_in *)addr;
@@ -1088,7 +1089,11 @@ static void mptcp_info2sockaddr(const struct mptcp_addr_info
*info,
else if (addr->ss_family == AF_INET6) {
struct sockaddr_in6 *in6_addr = (struct sockaddr_in6 *)addr;
- in6_addr->sin6_addr = info->addr6;
+ if (info->family == AF_INET)
+ ipv6_addr_set_v4mapped(info->addr.s_addr,
+ &in6_addr->sin6_addr);
+ else
+ in6_addr->sin6_addr = info->addr6;
in6_addr->sin6_port = info->port;
}
#endif
@@ -1132,11 +1137,11 @@ int __mptcp_subflow_connect(struct sock *sk, const struct
mptcp_addr_info *loc,
subflow->remote_key = msk->remote_key;
subflow->local_key = msk->local_key;
subflow->token = msk->token;
- mptcp_info2sockaddr(loc, &addr);
+ mptcp_info2sockaddr(loc, &addr, ssk->sk_family);
addrlen = sizeof(struct sockaddr_in);
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
- if (loc->family == AF_INET6)
+ if (addr.ss_family == AF_INET6)
addrlen = sizeof(struct sockaddr_in6);
#endif
ssk->sk_bound_dev_if = loc->ifindex;
@@ -1152,7 +1157,7 @@ int __mptcp_subflow_connect(struct sock *sk, const struct
mptcp_addr_info *loc,
subflow->remote_id = remote_id;
subflow->request_join = 1;
subflow->request_bkup = !!(loc->flags & MPTCP_PM_ADDR_FLAG_BACKUP);
- mptcp_info2sockaddr(remote, &addr);
+ mptcp_info2sockaddr(remote, &addr, ssk->sk_family);
mptcp_add_pending_subflow(msk, subflow);
err = kernel_connect(sf, (struct sockaddr *)&addr, addrlen, O_NONBLOCK);
--
2.29.2