[PATCH][RESEND 3] IPv6: 6rd tunnel mode

[PATCH][RESEND 3] IPv6: 6rd tunnel mode

[Alexandre Cassen]

This patch add support to 6rd tunnel mode as described into
draft-despres-6rd-03.

Patch history :
* http://patchwork.ozlabs.org/patch/26870/
* http://patchwork.ozlabs.org/patch/34026/
* http://patchwork.ozlabs.org/patch/34045/

IPv6 rapid deployment (draft-despres-6rd-03) builds upon mechanisms
of 6to4 (RFC3056) to enable a service provider to rapidly deploy IPv6
unicast service to IPv4 sites to which it provides customer premise
equipment. Like 6to4, it utilizes stateless IPv6 in IPv4 encapsulation
in order to transit IPv4-only network infrastructure. Unlike 6to4, a
6rd service provider uses an IPv6 prefix of its own in place of the
fixed 6to4 prefix.

Signed-off-by: Alexandre Cassen <acassen@freebox.fr>
---
 include/linux/if_tunnel.h |   10 +++++
 include/net/ipip.h        |    2 +
 net/ipv6/Kconfig          |   13 +++++++
 net/ipv6/sit.c            |   84 +++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 109 insertions(+), 0 deletions(-)

diff --git a/include/linux/if_tunnel.h b/include/linux/if_tunnel.h
index 5eb9b0f..0d44376 100644
--- a/include/linux/if_tunnel.h
+++ b/include/linux/if_tunnel.h
@@ -15,6 +15,10 @@
 #define SIOCADDPRL      (SIOCDEVPRIVATE + 5)
 #define SIOCDELPRL      (SIOCDEVPRIVATE + 6)
 #define SIOCCHGPRL      (SIOCDEVPRIVATE + 7)
+#define SIOCGET6RD      (SIOCDEVPRIVATE + 8)
+#define SIOCADD6RD      (SIOCDEVPRIVATE + 9)
+#define SIOCDEL6RD      (SIOCDEVPRIVATE + 10)
+#define SIOCCHG6RD      (SIOCDEVPRIVATE + 11)
 
 #define GRE_CSUM	__cpu_to_be16(0x8000)
 #define GRE_ROUTING	__cpu_to_be16(0x4000)
@@ -51,6 +55,12 @@ struct ip_tunnel_prl {
 /* PRL flags */
 #define	PRL_DEFAULT		0x0001
 
+/* 6RD parms */
+struct ip_tunnel_6rd {
+	struct in6_addr		addr;
+	__u8			prefixlen;
+};
+
 enum
 {
 	IFLA_GRE_UNSPEC,
diff --git a/include/net/ipip.h b/include/net/ipip.h
index 5d3036f..fa92c41 100644
--- a/include/net/ipip.h
+++ b/include/net/ipip.h
@@ -26,6 +26,8 @@ struct ip_tunnel
 
 	struct ip_tunnel_prl_entry	*prl;		/* potential router list */
 	unsigned int			prl_count;	/* # of entries in PRL */
+
+	struct ip_tunnel_6rd	ip6rd_prefix;	/* 6RD SP prefix */
 };
 
 /* ISATAP: default interval between RS in secondy */
diff --git a/net/ipv6/Kconfig b/net/ipv6/Kconfig
index ead6c7a..8b779f7 100644
--- a/net/ipv6/Kconfig
+++ b/net/ipv6/Kconfig
@@ -170,6 +170,19 @@ config IPV6_SIT
 
 	  Saying M here will produce a module called sit. If unsure, say Y.
 
+config IPV6_SIT_6RD
+	bool "IPv6: 6rd tunnel mode (EXPERIMENTAL)"
+	depends on IPV6_SIT && EXPERIMENTAL
+	default n
+	---help---
+	IPv6 rapid deployment (draft-despres-6rd-03) builds upon mechanisms
+	of 6to4 (RFC3056) to enable a service provider to rapidly deploy IPv6
+	unicast service to IPv4 sites to which it provides customer premise
+	equipment. Like 6to4, it utilizes stateless IPv6 in IPv4 encapsulation
+	in order to transit IPv4-only network infrastructure. Unlike 6to4, a
+	6rd service provider uses an IPv6 prefix of its own in place of the
+	fixed 6to4 prefix.
+
 config IPV6_NDISC_NODETYPE
 	bool
 
diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index 0ae4f64..3587149 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -604,6 +604,30 @@ static inline __be32 try_6to4(struct in6_addr *v6dst)
 	return dst;
 }
 
+#ifdef CONFIG_IPV6_SIT_6RD
+/* Returns the embedded IPv4 address if the IPv6 address comes from
+   6rd rule */
+
+static inline __be32 try_6rd(struct in6_addr *addr, u8 prefix_len, struct in6_addr *v6dst)
+{
+	__be32 dst = 0;
+
+	/* isolate addr according to mask */
+	if (ipv6_prefix_equal(v6dst, addr, prefix_len)) {
+		unsigned int d32_off, bits;
+
+		d32_off = prefix_len >> 5;
+		bits = (prefix_len & 0x1f);
+
+		dst = (ntohl(v6dst->s6_addr32[d32_off]) << bits);
+		if (bits)
+			dst |= ntohl(v6dst->s6_addr32[d32_off + 1]) >> (32 - bits);
+		dst = htonl(dst);
+	}
+	return dst;
+}
+#endif
+
 /*
  *	This function assumes it is being called from dev_queue_xmit()
  *	and that skb is filled properly by that function.
@@ -657,6 +681,13 @@ static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb,
 			goto tx_error;
 	}
 
+#ifdef CONFIG_IPV6_SIT_6RD
+	if (!dst && tunnel->ip6rd_prefix.prefixlen)
+		dst = try_6rd(&tunnel->ip6rd_prefix.addr,
+			      tunnel->ip6rd_prefix.prefixlen,
+			      &iph6->daddr);
+	else
+#endif
 	if (!dst)
 		dst = try_6to4(&iph6->daddr);
 
@@ -848,6 +879,9 @@ ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
 	int err = 0;
 	struct ip_tunnel_parm p;
 	struct ip_tunnel_prl prl;
+#ifdef CONFIG_IPV6_SIT_6RD
+	struct ip_tunnel_6rd ip6rd;
+#endif
 	struct ip_tunnel *t;
 	struct net *net = dev_net(dev);
 	struct sit_net *sitn = net_generic(net, sit_net_id);
@@ -987,6 +1021,56 @@ ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
 		netdev_state_change(dev);
 		break;
 
+#ifdef CONFIG_IPV6_SIT_6RD
+	case SIOCGET6RD:
+		err = -EINVAL;
+		if (dev == sitn->fb_tunnel_dev)
+			goto done;
+		err = -ENOENT;
+		if (!(t = netdev_priv(dev)))
+			goto done;
+		memcpy(&ip6rd, &t->ip6rd_prefix, sizeof(ip6rd));
+		if (copy_to_user(ifr->ifr_ifru.ifru_data, &ip6rd, sizeof(ip6rd)))
+			err = -EFAULT;
+		else
+			err = 0;
+		break;
+
+	case SIOCADD6RD:
+	case SIOCDEL6RD:
+	case SIOCCHG6RD:
+		err = -EPERM;
+		if (!capable(CAP_NET_ADMIN))
+			goto done;
+		err = -EINVAL;
+		if (dev == sitn->fb_tunnel_dev)
+			goto done;
+		err = -EFAULT;
+		if (copy_from_user(&ip6rd, ifr->ifr_ifru.ifru_data, sizeof(ip6rd)))
+			goto done;
+		err = -ENOENT;
+		if (!(t = netdev_priv(dev)))
+			goto done;
+
+		err = 0;
+		switch (cmd) {
+		case SIOCDEL6RD:
+			memset(&t->ip6rd_prefix, 0, sizeof(ip6rd));
+			break;
+		case SIOCADD6RD:
+		case SIOCCHG6RD:
+			if (ip6rd.prefixlen >= 95) {
+				err = -EINVAL;
+				goto done;
+			}
+			ipv6_addr_copy(&t->ip6rd_prefix.addr, &ip6rd.addr);
+			t->ip6rd_prefix.prefixlen = ip6rd.prefixlen;
+			break;
+		}
+		netdev_state_change(dev);
+		break;
+#endif
+
 	default:
 		err = -EINVAL;
 	}
-- 
1.6.0.4

Re: [PATCH][RESEND 3] IPv6: 6rd tunnel mode

[Eric Dumazet]

Alexandre Cassen a écrit :
> This patch add support to 6rd tunnel mode as described into
> draft-despres-6rd-03.
> 
> Patch history :
> * http://patchwork.ozlabs.org/patch/26870/
> * http://patchwork.ozlabs.org/patch/34026/
> * http://patchwork.ozlabs.org/patch/34045/
> 
> IPv6 rapid deployment (draft-despres-6rd-03) builds upon mechanisms
> of 6to4 (RFC3056) to enable a service provider to rapidly deploy IPv6
> unicast service to IPv4 sites to which it provides customer premise
> equipment. Like 6to4, it utilizes stateless IPv6 in IPv4 encapsulation
> in order to transit IPv4-only network infrastructure. Unlike 6to4, a
> 6rd service provider uses an IPv6 prefix of its own in place of the
> fixed 6to4 prefix.
> 
> Signed-off-by: Alexandre Cassen <acassen@freebox.fr>
> ---
>  include/linux/if_tunnel.h |   10 +++++
>  include/net/ipip.h        |    2 +
>  net/ipv6/Kconfig          |   13 +++++++
>  net/ipv6/sit.c            |   84 +++++++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 109 insertions(+), 0 deletions(-)
> 
> diff --git a/include/linux/if_tunnel.h b/include/linux/if_tunnel.h
> index 5eb9b0f..0d44376 100644
> --- a/include/linux/if_tunnel.h
> +++ b/include/linux/if_tunnel.h
> @@ -15,6 +15,10 @@
>  #define SIOCADDPRL      (SIOCDEVPRIVATE + 5)
>  #define SIOCDELPRL      (SIOCDEVPRIVATE + 6)
>  #define SIOCCHGPRL      (SIOCDEVPRIVATE + 7)
> +#define SIOCGET6RD      (SIOCDEVPRIVATE + 8)
> +#define SIOCADD6RD      (SIOCDEVPRIVATE + 9)
> +#define SIOCDEL6RD      (SIOCDEVPRIVATE + 10)
> +#define SIOCCHG6RD      (SIOCDEVPRIVATE + 11)
>  
>  #define GRE_CSUM	__cpu_to_be16(0x8000)
>  #define GRE_ROUTING	__cpu_to_be16(0x4000)
> @@ -51,6 +55,12 @@ struct ip_tunnel_prl {
>  /* PRL flags */
>  #define	PRL_DEFAULT		0x0001
>  
> +/* 6RD parms */
> +struct ip_tunnel_6rd {
> +	struct in6_addr		addr;
> +	__u8			prefixlen;
> +};
> +
>  enum
>  {
>  	IFLA_GRE_UNSPEC,
> diff --git a/include/net/ipip.h b/include/net/ipip.h
> index 5d3036f..fa92c41 100644
> --- a/include/net/ipip.h
> +++ b/include/net/ipip.h
> @@ -26,6 +26,8 @@ struct ip_tunnel
>  
>  	struct ip_tunnel_prl_entry	*prl;		/* potential router list */
>  	unsigned int			prl_count;	/* # of entries in PRL */
> +
> +	struct ip_tunnel_6rd	ip6rd_prefix;	/* 6RD SP prefix */
>  };
>  
>  /* ISATAP: default interval between RS in secondy */
> diff --git a/net/ipv6/Kconfig b/net/ipv6/Kconfig
> index ead6c7a..8b779f7 100644
> --- a/net/ipv6/Kconfig
> +++ b/net/ipv6/Kconfig
> @@ -170,6 +170,19 @@ config IPV6_SIT
>  
>  	  Saying M here will produce a module called sit. If unsure, say Y.
>  
> +config IPV6_SIT_6RD
> +	bool "IPv6: 6rd tunnel mode (EXPERIMENTAL)"
> +	depends on IPV6_SIT && EXPERIMENTAL
> +	default n
> +	---help---
> +	IPv6 rapid deployment (draft-despres-6rd-03) builds upon mechanisms
> +	of 6to4 (RFC3056) to enable a service provider to rapidly deploy IPv6
> +	unicast service to IPv4 sites to which it provides customer premise
> +	equipment. Like 6to4, it utilizes stateless IPv6 in IPv4 encapsulation
> +	in order to transit IPv4-only network infrastructure. Unlike 6to4, a
> +	6rd service provider uses an IPv6 prefix of its own in place of the
> +	fixed 6to4 prefix.
> +
>  config IPV6_NDISC_NODETYPE
>  	bool
>  
> diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
> index 0ae4f64..3587149 100644
> --- a/net/ipv6/sit.c
> +++ b/net/ipv6/sit.c
> @@ -604,6 +604,30 @@ static inline __be32 try_6to4(struct in6_addr *v6dst)
>  	return dst;
>  }
>  
> +#ifdef CONFIG_IPV6_SIT_6RD
> +/* Returns the embedded IPv4 address if the IPv6 address comes from
> +   6rd rule */
> +
> +static inline __be32 try_6rd(struct in6_addr *addr, u8 prefix_len, struct in6_addr *v6dst)
> +{
> +	__be32 dst = 0;
> +
> +	/* isolate addr according to mask */
> +	if (ipv6_prefix_equal(v6dst, addr, prefix_len)) {
> +		unsigned int d32_off, bits;
> +
> +		d32_off = prefix_len >> 5;
> +		bits = (prefix_len & 0x1f);
> +
> +		dst = (ntohl(v6dst->s6_addr32[d32_off]) << bits);
> +		if (bits)
> +			dst |= ntohl(v6dst->s6_addr32[d32_off + 1]) >> (32 - bits);
> +		dst = htonl(dst);
> +	}
> +	return dst;
> +}
> +#endif
> +
>  /*
>   *	This function assumes it is being called from dev_queue_xmit()
>   *	and that skb is filled properly by that function.
> @@ -657,6 +681,13 @@ static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb,
>  			goto tx_error;
>  	}
>  
> +#ifdef CONFIG_IPV6_SIT_6RD
> +	if (!dst && tunnel->ip6rd_prefix.prefixlen)
> +		dst = try_6rd(&tunnel->ip6rd_prefix.addr,
> +			      tunnel->ip6rd_prefix.prefixlen,
> +			      &iph6->daddr);
> +	else
> +#endif
>  	if (!dst)
>  		dst = try_6to4(&iph6->daddr);
>  
> @@ -848,6 +879,9 @@ ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
>  	int err = 0;
>  	struct ip_tunnel_parm p;
>  	struct ip_tunnel_prl prl;
> +#ifdef CONFIG_IPV6_SIT_6RD
> +	struct ip_tunnel_6rd ip6rd;
> +#endif
>  	struct ip_tunnel *t;
>  	struct net *net = dev_net(dev);
>  	struct sit_net *sitn = net_generic(net, sit_net_id);
> @@ -987,6 +1021,56 @@ ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
>  		netdev_state_change(dev);
>  		break;
>  
> +#ifdef CONFIG_IPV6_SIT_6RD
> +	case SIOCGET6RD:
> +		err = -EINVAL;
> +		if (dev == sitn->fb_tunnel_dev)
> +			goto done;
> +		err = -ENOENT;
> +		if (!(t = netdev_priv(dev)))
> +			goto done;

> +		memcpy(&ip6rd, &t->ip6rd_prefix, sizeof(ip6rd));

Just wondering why you need a temporary ip6rd here,
why dont you copy_to_user(ifr->ifr_ifru.ifru_data, &t->ip6rd_prefix, sizeof(ip6rd)); ?

> +		if (copy_to_user(ifr->ifr_ifru.ifru_data, &ip6rd, sizeof(ip6rd)))
> +			err = -EFAULT;
> +		else
> +			err = 0;
> +		break;
> +
> +	case SIOCADD6RD:
> +	case SIOCDEL6RD:
> +	case SIOCCHG6RD:
> +		err = -EPERM;
> +		if (!capable(CAP_NET_ADMIN))
> +			goto done;
> +		err = -EINVAL;
> +		if (dev == sitn->fb_tunnel_dev)
> +			goto done;
> +		err = -EFAULT;
> +		if (copy_from_user(&ip6rd, ifr->ifr_ifru.ifru_data, sizeof(ip6rd)))
> +			goto done;
> +		err = -ENOENT;
> +		if (!(t = netdev_priv(dev)))
> +			goto done;
> +
> +		err = 0;
> +		switch (cmd) {
> +		case SIOCDEL6RD:
> +			memset(&t->ip6rd_prefix, 0, sizeof(ip6rd));
> +			break;
> +		case SIOCADD6RD:
> +		case SIOCCHG6RD:
> +			if (ip6rd.prefixlen >= 95) {
> +				err = -EINVAL;
> +				goto done;
> +			}
> +			ipv6_addr_copy(&t->ip6rd_prefix.addr, &ip6rd.addr);
> +			t->ip6rd_prefix.prefixlen = ip6rd.prefixlen;
> +			break;
> +		}
> +		netdev_state_change(dev);
> +		break;
> +#endif
> +
>  	default:
>  		err = -EINVAL;
>  	}

Re: [PATCH][RESEND 3] IPv6: 6rd tunnel mode

[Joe Perches]

On Wed, 2009-09-23 at 00:02 +0200, Alexandre Cassen wrote:
> diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
> index 0ae4f64..3587149 100644
> --- a/net/ipv6/sit.c
> +++ b/net/ipv6/sit.c
[]
> +static inline __be32 try_6rd(struct in6_addr *addr, u8 prefix_len, struct in6_addr *v6dst)
> +{
> +	__be32 dst = 0;
> +
> +	/* isolate addr according to mask */
> +	if (ipv6_prefix_equal(v6dst, addr, prefix_len)) {
> +		unsigned int d32_off, bits;
> +
> +		d32_off = prefix_len >> 5;
> +		bits = (prefix_len & 0x1f);
> +
> +		dst = (ntohl(v6dst->s6_addr32[d32_off]) << bits);

unnecessary parens and a sparse warning?
Perhaps use a temporary u32 and an htonl or cpu_to_be32 at the end?

> +		if (bits)
> +			dst |= ntohl(v6dst->s6_addr32[d32_off + 1]) >> (32 - bits);
> +		dst = htonl(dst);
> +	}
> +	return dst;
> +}
> +#endif

Re: [PATCH][RESEND 3] IPv6: 6rd tunnel mode

[Brian Haley]

Alexandre Cassen wrote:
>
> +/* 6RD parms */
> +struct ip_tunnel_6rd {
> +	struct in6_addr		addr;
> +	__u8			prefixlen;
> +};

Are you sure you're not going to want to add anything to this struct in
the future like ifindex or flags?  Since it's part of the API you'd want
to do that now.

-Brian

Re: [PATCH][RESEND 3] IPv6: 6rd tunnel mode

[Alexandre Cassen]

On Wed, 23 Sep 2009, Eric Dumazet wrote:
>> +#ifdef CONFIG_IPV6_SIT_6RD
>> +	case SIOCGET6RD:
>> +		err = -EINVAL;
>> +		if (dev == sitn->fb_tunnel_dev)
>> +			goto done;
>> +		err = -ENOENT;
>> +		if (!(t = netdev_priv(dev)))
>> +			goto done;
>
>> +		memcpy(&ip6rd, &t->ip6rd_prefix, sizeof(ip6rd));
>
> Just wondering why you need a temporary ip6rd here,
> why dont you copy_to_user(ifr->ifr_ifru.ifru_data, &t->ip6rd_prefix, sizeof(ip6rd)); ?
>
>> +		if (copy_to_user(ifr->ifr_ifru.ifru_data, &ip6rd, sizeof(ip6rd)))
>> +			err = -EFAULT;
>> +		else
>> +			err = 0;
>> +		break;

agreed. will fix.

Re: [PATCH][RESEND 3] IPv6: 6rd tunnel mode

[YOSHIFUJI Hideaki]

Hello.

First of all, thank you for this work.

On Wed, 23 Sep 2009 00:02:51 +0200
Alexandre Cassen <acassen@freebox.fr> wrote:

> This patch add support to 6rd tunnel mode as described into
> draft-despres-6rd-03.
> 
> Patch history :
> * http://patchwork.ozlabs.org/patch/26870/
> * http://patchwork.ozlabs.org/patch/34026/
> * http://patchwork.ozlabs.org/patch/34045/
> 
> IPv6 rapid deployment (draft-despres-6rd-03) builds upon mechanisms

Well, I was confused.  I think draft-softwire-ipv6-6rd
is the latest one, no?

Another comment is that we should combine 6to4
and 6rd.

In fact, I've been taking care of it since I met
with Mark Townsley last week.  Here's my tentative
version for reference.

Several points:
 - based on latest version.
 - share code path with 6to4.

(If anyone can invent better bitops,
it will great help...)

Regards,

--yoshfuji

----
>From 7c82f67d361155a2e8ee831c66c9663617ae45bc Mon Sep 17 00:00:00 2001
From: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Date: Tue, 22 Sep 2009 16:29:54 +0900
Subject: [PATCH] ipv6 sit: 6rd (IPv6 Rapid Deployment) Support.

IPv6 Rapid Deployment (6rd; draft-ietf-softwire-ipv6-6rd) builds upon
mechanisms of 6to4 (RFC3056) to enable a service provider to rapidly
deploy IPv6 unicast service to IPv4 sites to which it provides
customer premise equipment.  Like 6to4, it utilizes stateless IPv6 in
IPv4 encapsulation in order to transit IPv4-only network
infrastructure.  Unlike 6to4, a 6rd service provider uses an IPv6
prefix of its own in place of the fixed 6to4 prefix.

With this option enabled, the SIT driver offers 6rd functionality by
providing additional ioctl API to configure the IPv6 Prefix for in
stead of static 2002::/16 for 6to4.

Original patch was done by Alexandre Cassen <acassen@freebox.fr>
based on old Internet-Draft.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
---
 include/linux/if_tunnel.h |   11 ++++
 include/net/ipip.h        |   13 +++++
 net/ipv6/Kconfig          |   19 +++++++
 net/ipv6/sit.c            |  124 ++++++++++++++++++++++++++++++++++++++++++---
 4 files changed, 159 insertions(+), 8 deletions(-)

diff --git a/include/linux/if_tunnel.h b/include/linux/if_tunnel.h
index 5eb9b0f..cab4938 100644
--- a/include/linux/if_tunnel.h
+++ b/include/linux/if_tunnel.h
@@ -15,6 +15,10 @@
 #define SIOCADDPRL      (SIOCDEVPRIVATE + 5)
 #define SIOCDELPRL      (SIOCDEVPRIVATE + 6)
 #define SIOCCHGPRL      (SIOCDEVPRIVATE + 7)
+#define SIOCGET6RD      (SIOCDEVPRIVATE + 8)
+#define SIOCADD6RD      (SIOCDEVPRIVATE + 9)
+#define SIOCDEL6RD      (SIOCDEVPRIVATE + 10)
+#define SIOCCHG6RD      (SIOCDEVPRIVATE + 11)
 
 #define GRE_CSUM	__cpu_to_be16(0x8000)
 #define GRE_ROUTING	__cpu_to_be16(0x4000)
@@ -51,6 +55,13 @@ struct ip_tunnel_prl {
 /* PRL flags */
 #define	PRL_DEFAULT		0x0001
 
+struct ip_tunnel_6rd {
+	struct in6_addr		prefix;
+	__be32			relay_prefix;
+	__u16			prefixlen;
+	__u16			relay_prefixlen;
+};
+
 enum
 {
 	IFLA_GRE_UNSPEC,
diff --git a/include/net/ipip.h b/include/net/ipip.h
index 5d3036f..157be1c 100644
--- a/include/net/ipip.h
+++ b/include/net/ipip.h
@@ -7,6 +7,15 @@
 /* Keep error state on tunnel for 30 sec */
 #define IPTUNNEL_ERR_TIMEO	(30*HZ)
 
+/* 6rd prefix/relay information */
+struct ip_tunnel_6rd_parm
+{
+	struct in6_addr		prefix;
+	__be32			relay_prefix;
+	u16			prefixlen;
+	u16			relay_prefixlen;
+};
+
 struct ip_tunnel
 {
 	struct ip_tunnel	*next;
@@ -24,6 +33,10 @@ struct ip_tunnel
 
 	struct ip_tunnel_parm	parms;
 
+	/* for SIT */
+#ifdef CONFIG_IPV6_SIT_6RD
+	struct ip_tunnel_6rd_parm	ip6rd;
+#endif
 	struct ip_tunnel_prl_entry	*prl;		/* potential router list */
 	unsigned int			prl_count;	/* # of entries in PRL */
 };
diff --git a/net/ipv6/Kconfig b/net/ipv6/Kconfig
index ead6c7a..f561998 100644
--- a/net/ipv6/Kconfig
+++ b/net/ipv6/Kconfig
@@ -170,6 +170,25 @@ config IPV6_SIT
 
 	  Saying M here will produce a module called sit. If unsure, say Y.
 
+config IPV6_SIT_6RD
+	bool "IPv6: IPv6 Rapid Development (6RD) (EXPERIMENTAL)"
+	depends on IPV6_SIT && EXPERIMENTAL
+	default n
+	---help---
+	  IPv6 Rapid Deployment (6rd; draft-ietf-softwire-ipv6-6rd) builds upon
+	  mechanisms of 6to4 (RFC3056) to enable a service provider to rapidly
+	  deploy IPv6 unicast service to IPv4 sites to which it provides
+	  customer premise equipment.  Like 6to4, it utilizes stateless IPv6 in
+	  IPv4 encapsulation in order to transit IPv4-only network
+	  infrastructure.  Unlike 6to4, a 6rd service provider uses an IPv6
+	  prefix of its own in place of the fixed 6to4 prefix.
+
+	  With this option enabled, the SIT driver offers 6rd functionality by
+	  providing additional ioctl API to configure the IPv6 Prefix for in
+	  stead of static 2002::/16 for 6to4.
+
+	  If unsure, say N.
+
 config IPV6_NDISC_NODETYPE
 	bool
 
diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index 0ae4f64..14bd503 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -162,6 +162,21 @@ static void ipip6_tunnel_link(struct sit_net *sitn, struct ip_tunnel *t)
 	write_unlock_bh(&ipip6_lock);
 }
 
+static void ipip6_tunnel_clone_6rd(struct ip_tunnel *t, struct sit_net *sitn)
+{
+#ifdef CONFIG_IPV6_SIT_6RD
+	if (t->dev == sitn->fb_tunnel_dev) {
+		ipv6_addr_set(&t->ip6rd.prefix, htonl(0x20020000), 0, 0, 0);
+		t->ip6rd.relay_prefix = 0;
+		t->ip6rd.prefixlen = 16;
+		t->ip6rd.relay_prefixlen = 0;
+	} else {
+		struct ip_tunnel *t0 = netdev_priv(sitn->fb_tunnel_dev);
+		memcpy(&t->ip6rd, &t0->ip6rd, sizeof(t->ip6rd));
+	}
+#endif
+}
+
 static struct ip_tunnel * ipip6_tunnel_locate(struct net *net,
 		struct ip_tunnel_parm *parms, int create)
 {
@@ -214,6 +229,8 @@ static struct ip_tunnel * ipip6_tunnel_locate(struct net *net,
 
 	dev_hold(dev);
 
+	ipip6_tunnel_clone_6rd(t, sitn);
+
 	ipip6_tunnel_link(sitn, nt);
 	return nt;
 
@@ -590,17 +607,41 @@ out:
 	return 0;
 }
 
-/* Returns the embedded IPv4 address if the IPv6 address
-   comes from 6to4 (RFC 3056) addr space */
-
-static inline __be32 try_6to4(struct in6_addr *v6dst)
+/*
+ * Returns the embedded IPv4 address if the IPv6 address
+ * comes from 6rd / 6to4 (RFC 3056) addr space.
+ */
+static inline
+__be32 try_6rd(struct in6_addr *v6dst, struct ip_tunnel *tunnel)
 {
 	__be32 dst = 0;
 
+#ifdef CONFIG_IPV6_SIT_6RD
+	if (ipv6_prefix_equal(v6dst, &tunnel->ip6rd.prefix,
+			      tunnel->ip6rd.prefixlen)) {
+		unsigned pbw0, pbi0;
+		int pbi1;
+		u32 d;
+
+		pbw0 = tunnel->ip6rd.prefixlen >> 5;
+		pbi0 = tunnel->ip6rd.prefixlen & 0x1f;
+
+		d = (ntohl(tunnel->ip6rd.prefix.s6_addr32[pbw0]) << pbi0) >>
+		    tunnel->ip6rd.relay_prefixlen;
+
+		pbi1 = pbi0 - tunnel->ip6rd.relay_prefixlen;
+		if (pbi1 > 0)
+			d |= ntohl(tunnel->ip6rd.prefix.s6_addr32[pbw0 + 1]) >>
+			     (32 - pbi1);
+
+		dst = tunnel->ip6rd.relay_prefix | htonl(d);
+	}
+#else
 	if (v6dst->s6_addr16[0] == htons(0x2002)) {
 		/* 6to4 v6 addr has 16 bits prefix, 32 v4addr, 16 SLA, ... */
 		memcpy(&dst, &v6dst->s6_addr16[1], 4);
 	}
+#endif
 	return dst;
 }
 
@@ -658,7 +699,7 @@ static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb,
 	}
 
 	if (!dst)
-		dst = try_6to4(&iph6->daddr);
+		dst = try_6rd(&iph6->daddr, tunnel);
 
 	if (!dst) {
 		struct neighbour *neigh = NULL;
@@ -851,9 +892,15 @@ ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
 	struct ip_tunnel *t;
 	struct net *net = dev_net(dev);
 	struct sit_net *sitn = net_generic(net, sit_net_id);
+#ifdef CONFIG_IPV6_SIT_6RD
+	struct ip_tunnel_6rd ip6rd;
+#endif
 
 	switch (cmd) {
 	case SIOCGETTUNNEL:
+#ifdef CONFIG_IPV6_SIT_6RD
+	case SIOCGET6RD:
+#endif
 		t = NULL;
 		if (dev == sitn->fb_tunnel_dev) {
 			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
@@ -864,9 +911,25 @@ ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
 		}
 		if (t == NULL)
 			t = netdev_priv(dev);
-		memcpy(&p, &t->parms, sizeof(p));
-		if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
-			err = -EFAULT;
+
+		err = -EFAULT;
+		if (cmd == SIOCGETTUNNEL) {
+			memcpy(&p, &t->parms, sizeof(p));
+			if (copy_to_user(ifr->ifr_ifru.ifru_data, &p,
+					 sizeof(p)))
+				goto done;
+#ifdef CONFIG_IPV6_SIT_6RD
+		} else {
+			ipv6_addr_copy(&ip6rd.prefix, &t->ip6rd.prefix);
+			ip6rd.relay_prefix = t->ip6rd.relay_prefix;
+			ip6rd.prefixlen = t->ip6rd.prefixlen;
+			ip6rd.relay_prefixlen = t->ip6rd.relay_prefixlen;
+			if (copy_to_user(ifr->ifr_ifru.ifru_data, &ip6rd,
+					 sizeof(ip6rd)))
+				goto done;
+#endif
+		}
+		err = 0;
 		break;
 
 	case SIOCADDTUNNEL:
@@ -987,6 +1050,51 @@ ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
 		netdev_state_change(dev);
 		break;
 
+#ifdef CONFIG_IPV6_SIT_6RD
+	case SIOCADD6RD:
+	case SIOCCHG6RD:
+	case SIOCDEL6RD:
+		err = -EPERM;
+		if (!capable(CAP_NET_ADMIN))
+			goto done;
+
+		err = -EFAULT;
+		if (copy_from_user(&ip6rd, ifr->ifr_ifru.ifru_data,
+				   sizeof(ip6rd)))
+			goto done;
+
+		t = netdev_priv(dev);
+
+		if (cmd != SIOCDEL6RD) {
+			struct in6_addr prefix;
+			__be32 relay_prefix;
+
+			err = -EINVAL;
+			if (ip6rd.relay_prefixlen > 32 ||
+			    ip6rd.prefixlen + (32 - ip6rd.relay_prefixlen) > 64)
+				goto done;
+
+			ipv6_addr_prefix(&prefix, &ip6rd.prefix,
+					 ip6rd.prefixlen);
+			if (!ipv6_addr_equal(&prefix, &ip6rd.prefix))
+				goto done;
+			relay_prefix = ip6rd.relay_prefix &
+				       htonl(0xffffffffUL <<
+					     (32 - ip6rd.relay_prefixlen));
+			if (relay_prefix != ip6rd.relay_prefix)
+				goto done;
+
+			ipv6_addr_copy(&t->ip6rd.prefix, &prefix);
+			t->ip6rd.relay_prefix = relay_prefix;
+			t->ip6rd.prefixlen = ip6rd.prefixlen;
+			t->ip6rd.relay_prefixlen = ip6rd.relay_prefixlen;
+		} else
+			ipip6_tunnel_clone_6rd(t, sitn);
+
+		err = 0;
+		break;
+#endif
+
 	default:
 		err = -EINVAL;
 	}
-- 
1.5.6.5


--yoshfuji

Re: [PATCH][RESEND 3] IPv6: 6rd tunnel mode

[Alexandre Cassen]

On Wed, 2009-09-23 at 18:43 +0900, YOSHIFUJI Hideaki wrote:
> Hello.
> 
> First of all, thank you for this work.
> 
> On Wed, 23 Sep 2009 00:02:51 +0200
> Alexandre Cassen <acassen@freebox.fr> wrote:
> 
> > This patch add support to 6rd tunnel mode as described into
> > draft-despres-6rd-03.
> > 
> > Patch history :
> > * http://patchwork.ozlabs.org/patch/26870/
> > * http://patchwork.ozlabs.org/patch/34026/
> > * http://patchwork.ozlabs.org/patch/34045/
> > 
> > IPv6 rapid deployment (draft-despres-6rd-03) builds upon mechanisms
> 
> Well, I was confused.  I think draft-softwire-ipv6-6rd
> is the latest one, no?

draft-despres-6rd-03    : targeting informational RFC
                          (=> currently pending)
draft-softwire-ipv6-6rd : targeting standard track

after last IETF meeting previous draft-townsley-ipv6-6rd as been pushed
to IETG softwires WG.

So you right, ref should be set to draft-softwire-ipv6-6rd.

> Another comment is that we should combine 6to4
> and 6rd.

Completly agree. 6to4 is a special case of 6rd.

Okay, so I stop producing (fixing according to last comments) and
resending new patch for 6rd.

regs,
Alexandre

Re: [PATCH][RESEND 3] IPv6: 6rd tunnel mode

[David Miller]

From: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Date: Wed, 23 Sep 2009 18:43:14 +0900

> Subject: [PATCH] ipv6 sit: 6rd (IPv6 Rapid Deployment) Support.
> 
> IPv6 Rapid Deployment (6rd; draft-ietf-softwire-ipv6-6rd) builds upon
> mechanisms of 6to4 (RFC3056) to enable a service provider to rapidly
> deploy IPv6 unicast service to IPv4 sites to which it provides
> customer premise equipment.  Like 6to4, it utilizes stateless IPv6 in
> IPv4 encapsulation in order to transit IPv4-only network
> infrastructure.  Unlike 6to4, a 6rd service provider uses an IPv6
> prefix of its own in place of the fixed 6to4 prefix.
> 
> With this option enabled, the SIT driver offers 6rd functionality by
> providing additional ioctl API to configure the IPv6 Prefix for in
> stead of static 2002::/16 for 6to4.
> 
> Original patch was done by Alexandre Cassen <acassen@freebox.fr>
> based on old Internet-Draft.
> 
> Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

Applied, thanks everyone.

Re: [PATCH][RESEND 3] IPv6: 6rd tunnel mode

[Steffen Klassert]

On Wed, Oct 07, 2009 at 01:24:36AM -0700, David Miller wrote:
> From: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
> Date: Wed, 23 Sep 2009 18:43:14 +0900
> 
> > Subject: [PATCH] ipv6 sit: 6rd (IPv6 Rapid Deployment) Support.
> > 

I'm getting the following compile error after applying this patch:

  CC      net/ipv6/ip6_tunnel.o
 In file included from
/home/klassert/git/linux-sinafe-2.6/net/ipv6/ip6_tunnel.c:30:
 /home/klassert/git/linux-sinafe-2.6/include/linux/if_tunnel.h:59:
error: field 'prefix' has incomplete type
 make[3]: *** [net/ipv6/ip6_tunnel.o] Error 1

We probaply missing include/linux/in6.h in include/linux/if_tunnel.h
The patch below adds the missing include.

---  

Subject: [PATCH] if_tunnel.h: Add missing include

This patch fixes the following compile error:

  CC      net/ipv6/ip6_tunnel.o
 In file included from /home/klassert/git/linux-sinafe-2.6/net/ipv6/ip6_tunnel.c:30:
 /home/klassert/git/linux-sinafe-2.6/include/linux/if_tunnel.h:59: error: field 'prefix' has incomplete type
 make[3]: *** [net/ipv6/ip6_tunnel.o] Error 1

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 include/linux/if_tunnel.h |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/include/linux/if_tunnel.h b/include/linux/if_tunnel.h
index c53c8e0..8d76cb4 100644
--- a/include/linux/if_tunnel.h
+++ b/include/linux/if_tunnel.h
@@ -5,6 +5,7 @@
 
 #ifdef __KERNEL__
 #include <linux/ip.h>
+#include <linux/in6.h>
 #endif
 
 #define SIOCGETTUNNEL   (SIOCDEVPRIVATE + 0)
-- 
1.5.4.2