Re: [PATCH net-next v3 3/9] ipv6: sr: add support for SRH encapsulation and injection with lwtunnels

[Roopa Prabhu]

On 10/27/16, 6:33 AM, David Lebrun wrote:
> This patch creates a new type of interfaceless lightweight tunnel (SEG6),
> enabling the encapsulation and injection of SRH within locally emitted
> packets and forwarded packets.
>
> From a configuration viewpoint, a seg6 tunnel would be configured as follows:
>
>   ip -6 ro ad fc00::1/128 encap seg6 mode encap segs fc42::1,fc42::2,fc42::3 
> dev eth0
>
> Any packet whose destination address is fc00::1 would thus be encapsulated
> within an outer IPv6 header containing the SRH with three segments, and would
> actually be routed to the first segment of the list. If `mode inline' was
> specified instead of `mode encap', then the SRH would be directly inserted
> after the IPv6 header without outer encapsulation.
>
> Signed-off-by: David Lebrun 
>
Acked-by: Roopa Prabhu 

Re: [PATCH net-next v3 3/9] ipv6: sr: add support for SRH encapsulation and injection with lwtunnels

[kbuild test robot]

Hi David,

[auto build test ERROR on net-next/master]

url:
https://github.com/0day-ci/linux/commits/David-Lebrun/ipv6-implement-dataplane-support-for-rthdr-type-4-Segment-Routing-Header/20161027-233201
config: arm-iop13xx_defconfig (attached as .config)
compiler: arm-linux-gnueabi-gcc (Debian 6.1.1-9) 6.1.1 20160705
reproduce:
wget 
https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross
 -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=arm 

All errors (new ones prefixed by >>):

   net/built-in.o: In function `seg6_output':
>> sysctl_net.c:(.text+0xdfc8c): undefined reference to `dst_cache_get'
>> sysctl_net.c:(.text+0xdfd78): undefined reference to `dst_cache_set_ip6'

---
0-DAY kernel test infrastructureOpen Source Technology Center
https://lists.01.org/pipermail/kbuild-all   Intel Corporation


.config.gz
Description: application/gzip

[PATCH net-next v3 3/9] ipv6: sr: add support for SRH encapsulation and injection with lwtunnels

[David Lebrun]

This patch creates a new type of interfaceless lightweight tunnel (SEG6),
enabling the encapsulation and injection of SRH within locally emitted
packets and forwarded packets.

>From a configuration viewpoint, a seg6 tunnel would be configured as follows:

  ip -6 ro ad fc00::1/128 encap seg6 mode encap segs fc42::1,fc42::2,fc42::3 
dev eth0

Any packet whose destination address is fc00::1 would thus be encapsulated
within an outer IPv6 header containing the SRH with three segments, and would
actually be routed to the first segment of the list. If `mode inline' was
specified instead of `mode encap', then the SRH would be directly inserted
after the IPv6 header without outer encapsulation.

Signed-off-by: David Lebrun 
---
 include/linux/seg6_iptunnel.h  |   6 +
 include/net/seg6.h |   3 +
 include/uapi/linux/lwtunnel.h  |   1 +
 include/uapi/linux/seg6_iptunnel.h |  41 +
 net/core/lwtunnel.c|   2 +
 net/ipv6/Makefile  |   2 +-
 net/ipv6/seg6.c|   7 +
 net/ipv6/seg6_iptunnel.c   | 365 +
 8 files changed, 426 insertions(+), 1 deletion(-)
 create mode 100644 include/linux/seg6_iptunnel.h
 create mode 100644 include/uapi/linux/seg6_iptunnel.h
 create mode 100644 net/ipv6/seg6_iptunnel.c

diff --git a/include/linux/seg6_iptunnel.h b/include/linux/seg6_iptunnel.h
new file mode 100644
index 000..5377cf6
--- /dev/null
+++ b/include/linux/seg6_iptunnel.h
@@ -0,0 +1,6 @@
+#ifndef _LINUX_SEG6_IPTUNNEL_H
+#define _LINUX_SEG6_IPTUNNEL_H
+
+#include 
+
+#endif
diff --git a/include/net/seg6.h b/include/net/seg6.h
index 0cdd669..7ff7403 100644
--- a/include/net/seg6.h
+++ b/include/net/seg6.h
@@ -16,6 +16,7 @@
 
 #include 
 #include 
+#include 
 
 struct seg6_pernet_data {
struct mutex lock;
@@ -29,5 +30,7 @@ static inline struct seg6_pernet_data *seg6_pernet(struct net 
*net)
 
 extern int seg6_init(void);
 extern void seg6_exit(void);
+extern int seg6_iptunnel_init(void);
+extern void seg6_iptunnel_exit(void);
 
 #endif
diff --git a/include/uapi/linux/lwtunnel.h b/include/uapi/linux/lwtunnel.h
index a478fe8..453cc62 100644
--- a/include/uapi/linux/lwtunnel.h
+++ b/include/uapi/linux/lwtunnel.h
@@ -9,6 +9,7 @@ enum lwtunnel_encap_types {
LWTUNNEL_ENCAP_IP,
LWTUNNEL_ENCAP_ILA,
LWTUNNEL_ENCAP_IP6,
+   LWTUNNEL_ENCAP_SEG6,
__LWTUNNEL_ENCAP_MAX,
 };
 
diff --git a/include/uapi/linux/seg6_iptunnel.h 
b/include/uapi/linux/seg6_iptunnel.h
new file mode 100644
index 000..da5524a
--- /dev/null
+++ b/include/uapi/linux/seg6_iptunnel.h
@@ -0,0 +1,41 @@
+/*
+ *  SR-IPv6 implementation
+ *
+ *  Author:
+ *  David Lebrun 
+ *
+ *
+ *  This program is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License
+ *  as published by the Free Software Foundation; either version
+ *  2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _UAPI_LINUX_SEG6_IPTUNNEL_H
+#define _UAPI_LINUX_SEG6_IPTUNNEL_H
+
+enum {
+   SEG6_IPTUNNEL_UNSPEC,
+   SEG6_IPTUNNEL_SRH,
+   __SEG6_IPTUNNEL_MAX,
+};
+#define SEG6_IPTUNNEL_MAX (__SEG6_IPTUNNEL_MAX - 1)
+
+struct seg6_iptunnel_encap {
+   int flags;
+   struct ipv6_sr_hdr srh[0];
+};
+
+#define SEG6_IPTUN_ENCAP_SIZE(x) ((sizeof(*x)) + (((x)->srh->hdrlen + 1) << 3))
+
+#define SEG6_IPTUN_FLAG_ENCAP   0x1
+
+static inline size_t seg6_lwt_headroom(struct seg6_iptunnel_encap *tuninfo)
+{
+   int encap = !!(tuninfo->flags & SEG6_IPTUN_FLAG_ENCAP);
+
+   return ((tuninfo->srh->hdrlen + 1) << 3) +
+  (encap * sizeof(struct ipv6hdr));
+}
+
+#endif
diff --git a/net/core/lwtunnel.c b/net/core/lwtunnel.c
index 88fd642..03976e9 100644
--- a/net/core/lwtunnel.c
+++ b/net/core/lwtunnel.c
@@ -39,6 +39,8 @@ static const char *lwtunnel_encap_str(enum 
lwtunnel_encap_types encap_type)
return "MPLS";
case LWTUNNEL_ENCAP_ILA:
return "ILA";
+   case LWTUNNEL_ENCAP_SEG6:
+   return "SEG6";
case LWTUNNEL_ENCAP_IP6:
case LWTUNNEL_ENCAP_IP:
case LWTUNNEL_ENCAP_NONE:
diff --git a/net/ipv6/Makefile b/net/ipv6/Makefile
index c92010d..59ee92f 100644
--- a/net/ipv6/Makefile
+++ b/net/ipv6/Makefile
@@ -9,7 +9,7 @@ ipv6-objs :=af_inet6.o anycast.o ip6_output.o ip6_input.o 
addrconf.o \
route.o ip6_fib.o ipv6_sockglue.o ndisc.o udp.o udplite.o \
raw.o icmp.o mcast.o reassembly.o tcp_ipv6.o ping.o \
exthdrs.o datagram.o ip6_flowlabel.o inet6_connection_sock.o \
-   udp_offload.o seg6.o
+   udp_offload.o seg6.o seg6_iptunnel.o
 
 ipv6-offload :=ip6_offload.o tcpv6_offload.o exthdrs_offload.o
 
diff --git a/net/ipv6/seg6.c b/net/ipv6/seg6.c
index 9cca051..fb9ebea 100644
--- a/net/ipv6/seg6.c
+++ b/net/ipv6/seg6.c
@@ -193,10 +193,16