From b9961cdb54c22fa1b3f1eac5446a008fde7532e6 Mon Sep 17 00:00:00 2001

From: Andrea Claudi <aclaudi@redhat.com>

Date: Wed, 5 Jun 2019 13:13:31 +0200

Subject: [PATCH] gre6: add collect metadata support

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1714660

Upstream Status: iproute2.git commit 6231c5bec6d25

Conflicts:

* Context change due to missing commit

  ad4b1425c3182 ("iplink: Expose IFLA_*_FWMARK attributes for supported link types")

* Adjusted gre_print_opt() to missing commit 6856fb65484ba

  ("ip: link_gre6.c: add json output support")

commit 6231c5bec6d256f7861f39d3a578f5259f274cc4

Author: William Tu <u9012063@gmail.com>

Date:   Tue Dec 12 18:22:52 2017 -0800

    gre6: add collect metadata support

    The patch adds 'external' option to support collect metadata

    gre6 tunnel.  The 'external' keyword is already used to set the

    device into collect metadata mode such as vxlan, geneve, ipip,

    etc.  This patch extends support for ipv6 gre and gretap.

    Example of L3 and L2 gre device:

    bash:~# ip link add dev ip6gre123 type ip6gre external

    bash:~# ip link add dev ip6gretap123 type ip6gretap external

    Signed-off-by: William Tu <u9012063@gmail.com>

    Cc: Daniel Borkmann <daniel@iogearbox.net>

---

 ip/link_gre6.c        | 49 ++++++++++++++++++++++++++++---------------

 man/man8/ip-link.8.in | 17 +++++++++++++++

 2 files changed, 49 insertions(+), 17 deletions(-)

diff --git a/ip/link_gre6.c b/ip/link_gre6.c

index 127e51de4ab73..ea42fb1a9f664 100644

--- a/ip/link_gre6.c

+++ b/ip/link_gre6.c

@@ -102,6 +102,7 @@ static int gre_parse_opt(struct link_util *lu, int argc, char **argv,

 	__u16 encapflags = TUNNEL_ENCAP_FLAG_CSUM6;

 	__u16 encapsport = 0;

 	__u16 encapdport = 0;

+	__u8 metadata = 0;

 	int len;

 	if (!(n->nlmsg_flags & NLM_F_CREATE)) {

@@ -173,6 +174,9 @@ get_failed:

 		if (greinfo[IFLA_GRE_ENCAP_SPORT])

 			encapsport = rta_getattr_u16(greinfo[IFLA_GRE_ENCAP_SPORT]);

+		if (greinfo[IFLA_GRE_COLLECT_METADATA])

+			metadata = 1;

+

 		if (greinfo[IFLA_GRE_ENCAP_DPORT])

 			encapdport = rta_getattr_u16(greinfo[IFLA_GRE_ENCAP_DPORT]);

@@ -333,6 +337,8 @@ get_failed:

 			encapflags |= TUNNEL_ENCAP_FLAG_REMCSUM;

 		} else if (strcmp(*argv, "noencap-remcsum") == 0) {

 			encapflags &= ~TUNNEL_ENCAP_FLAG_REMCSUM;

+		} else if (strcmp(*argv, "external") == 0) {

+			metadata = 1;

 		} else if (strcmp(*argv, "encaplimit") == 0) {

 			NEXT_ARG();

 			if (strcmp(*argv, "none") == 0) {

@@ -350,23 +356,27 @@ get_failed:

 		argc--; argv++;

 	}

-	addattr32(n, 1024, IFLA_GRE_IKEY, ikey);

-	addattr32(n, 1024, IFLA_GRE_OKEY, okey);

-	addattr_l(n, 1024, IFLA_GRE_IFLAGS, &iflags, 2);

-	addattr_l(n, 1024, IFLA_GRE_OFLAGS, &oflags, 2);

-	addattr_l(n, 1024, IFLA_GRE_LOCAL, &laddr, sizeof(laddr));

-	addattr_l(n, 1024, IFLA_GRE_REMOTE, &raddr, sizeof(raddr));

-	if (link)

-		addattr32(n, 1024, IFLA_GRE_LINK, link);

-	addattr_l(n, 1024, IFLA_GRE_TTL, &hop_limit, 1);

-	addattr_l(n, 1024, IFLA_GRE_ENCAP_LIMIT, &encap_limit, 1);

-	addattr_l(n, 1024, IFLA_GRE_FLOWINFO, &flowinfo, 4);

-	addattr32(n, 1024, IFLA_GRE_FLAGS, flags);

-

-	addattr16(n, 1024, IFLA_GRE_ENCAP_TYPE, encaptype);

-	addattr16(n, 1024, IFLA_GRE_ENCAP_FLAGS, encapflags);

-	addattr16(n, 1024, IFLA_GRE_ENCAP_SPORT, htons(encapsport));

-	addattr16(n, 1024, IFLA_GRE_ENCAP_DPORT, htons(encapdport));

+	if (!metadata) {

+		addattr32(n, 1024, IFLA_GRE_IKEY, ikey);

+		addattr32(n, 1024, IFLA_GRE_OKEY, okey);

+		addattr_l(n, 1024, IFLA_GRE_IFLAGS, &iflags, 2);

+		addattr_l(n, 1024, IFLA_GRE_OFLAGS, &oflags, 2);

+		addattr_l(n, 1024, IFLA_GRE_LOCAL, &laddr, sizeof(laddr));

+		addattr_l(n, 1024, IFLA_GRE_REMOTE, &raddr, sizeof(raddr));

+		if (link)

+			addattr32(n, 1024, IFLA_GRE_LINK, link);

+		addattr_l(n, 1024, IFLA_GRE_TTL, &hop_limit, 1);

+		addattr_l(n, 1024, IFLA_GRE_ENCAP_LIMIT, &encap_limit, 1);

+		addattr_l(n, 1024, IFLA_GRE_FLOWINFO, &flowinfo, 4);

+		addattr32(n, 1024, IFLA_GRE_FLAGS, flags);

+

+		addattr16(n, 1024, IFLA_GRE_ENCAP_TYPE, encaptype);

+		addattr16(n, 1024, IFLA_GRE_ENCAP_FLAGS, encapflags);

+		addattr16(n, 1024, IFLA_GRE_ENCAP_SPORT, htons(encapsport));

+		addattr16(n, 1024, IFLA_GRE_ENCAP_DPORT, htons(encapdport));

+	} else {

+		addattr_l(n, 1024, IFLA_GRE_COLLECT_METADATA, NULL, 0);

+	}

 	return 0;

 }

@@ -385,6 +395,11 @@ static void gre_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])

 	if (!tb)

 		return;

+	if (tb[IFLA_GRE_COLLECT_METADATA]) {

+		fprintf(f, "external");

+		return;

+	}

+

 	if (tb[IFLA_GRE_FLAGS])

 		flags = rta_getattr_u32(tb[IFLA_GRE_FLAGS]);

diff --git a/man/man8/ip-link.8.in b/man/man8/ip-link.8.in

index 8be5d5e1e9fd6..612bd8ce92696 100644

--- a/man/man8/ip-link.8.in

+++ b/man/man8/ip-link.8.in

@@ -877,6 +877,8 @@ the following additional arguments are supported:

 .BI "dscp inherit"

 ] [

 .BI dev " PHYS_DEV "

+] [

+.RB external

 ]

 .in +8

@@ -958,6 +960,21 @@ or

 .IR 00 ".." ff

 when tunneling non-IP packets. The default value is 00.

+.sp

+.RB external

+- make this tunnel externally controlled (or not, which is the default).

+In the kernel, this is referred to as collect metadata mode.  This flag is

+mutually exclusive with the

+.BR remote ,

+.BR local ,

+.BR seq ,

+.BR key,

+.BR csum,

+.BR hoplimit,

+.BR encaplimit,

+.BR flowlabel " and " tclass

+options.

+

 .in -8

 .TP

-- 

2.20.1