xfrm: add an interface to offload policy

Extend at "ip xfrm policy" to allow policy offload to specific device.
The syntax and the code follow already established pattern from the
state offload.

The only difference between them is that direction was already mandatory
argument in policy configuration commands, so don't need to add direction
handling logic like it was done for the state offload.

The syntax is as follows:
 $ ip xfrm policy .... offload packet dev <if-name>

Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: David Ahern <dsahern@kernel.org>

ip/ipxfrm.c

@@ -688,8 +688,8 @@ done:
 	return 0;
 }
 
-void xfrm_xfrma_print(struct rtattr *tb[], __u16 family,
+void xfrm_xfrma_print(struct rtattr *tb[], __u16 family, FILE *fp,
-		      FILE *fp, const char *prefix, bool nokeys)
+		      const char *prefix, bool nokeys, bool dir)
 {
 	if (tb[XFRMA_MARK]) {
 		struct rtattr *rta = tb[XFRMA_MARK];
@@ -895,9 +895,12 @@ void xfrm_xfrma_print(struct rtattr *tb[], __u16 family,
 
 		xuo = (struct xfrm_user_offload *)
 			RTA_DATA(tb[XFRMA_OFFLOAD_DEV]);
-		fprintf(fp, "dev %s dir %s mode %s",
+		fprintf(fp, "dev %s ",
-			ll_index_to_name(xuo->ifindex),
+			ll_index_to_name(xuo->ifindex));
-			(xuo->flags & XFRM_OFFLOAD_INBOUND) ? "in" : "out",
+		if (dir)
+			fprintf(fp, "dir %s ",
+			(xuo->flags & XFRM_OFFLOAD_INBOUND) ? "in" : "out");
+		fprintf(fp, "mode %s",
 			(xuo->flags & XFRM_OFFLOAD_PACKET) ? "packet" : "crypto");
 		fprintf(fp, "%s", _SL_);
 	}
@@ -990,7 +993,7 @@ void xfrm_state_info_print(struct xfrm_usersa_info *xsinfo,
 		fprintf(fp, " (0x%s)", strxf_mask8(xsinfo->flags));
 	fprintf(fp, "%s", _SL_);
 
-	xfrm_xfrma_print(tb, xsinfo->family, fp, buf, nokeys);
+	xfrm_xfrma_print(tb, xsinfo->family, fp, buf, nokeys, true);
 
 	if (!xfrm_selector_iszero(&xsinfo->sel)) {
 		char sbuf[STRBUF_SIZE];
@@ -1096,7 +1099,7 @@ void xfrm_policy_info_print(struct xfrm_userpolicy_info *xpinfo,
 	if (show_stats > 0)
 		xfrm_lifetime_print(&xpinfo->lft, &xpinfo->curlft, fp, buf);
 
-	xfrm_xfrma_print(tb, xpinfo->sel.family, fp, buf, false);
+	xfrm_xfrma_print(tb, xpinfo->sel.family, fp, buf, false, false);
 }
 
 int xfrm_id_parse(xfrm_address_t *saddr, struct xfrm_id *id, __u16 *family,

ip/xfrm.h

@@ -124,8 +124,8 @@ const char *strxf_proto(__u8 proto);
 const char *strxf_ptype(__u8 ptype);
 void xfrm_selector_print(struct xfrm_selector *sel, __u16 family,
 			 FILE *fp, const char *prefix);
-void xfrm_xfrma_print(struct rtattr *tb[], __u16 family,
+void xfrm_xfrma_print(struct rtattr *tb[], __u16 family, FILE *fp,
-		      FILE *fp, const char *prefix, bool nokeys);
+		      const char *prefix, bool nokeys, bool dir);
 void xfrm_state_info_print(struct xfrm_usersa_info *xsinfo,
 			    struct rtattr *tb[], FILE *fp, const char *prefix,
 			   const char *title, bool nokeys);

ip/xfrm_monitor.c

@@ -199,7 +199,7 @@ static int xfrm_report_print(struct nlmsghdr *n, void *arg)
 
 	parse_rtattr(tb, XFRMA_MAX, XFRMREP_RTA(xrep), len);
 
-	xfrm_xfrma_print(tb, family, fp, "  ", nokeys);
+	xfrm_xfrma_print(tb, family, fp, "  ", nokeys, true);
 
 	if (oneline)
 		fprintf(fp, "\n");

ip/xfrm_policy.c

@@ -57,6 +57,7 @@ static void usage(void)
 		"	[ mark MARK [ mask MASK ] ] [ index INDEX ] [ ptype PTYPE ]\n"
 		"	[ action ACTION ] [ priority PRIORITY ] [ flag FLAG-LIST ]\n"
 		"	[ if_id IF_ID ] [ LIMIT-LIST ] [ TMPL-LIST ]\n"
+		"	[ offload packet dev DEV] } ]\n"
 		"Usage: ip xfrm policy { delete | get } { SELECTOR | index INDEX } dir DIR\n"
 		"	[ ctx CTX ] [ mark MARK [ mask MASK ] ] [ ptype PTYPE ]\n"
 		"	[ if_id IF_ID ]\n"
@@ -260,6 +261,7 @@ static int xfrm_policy_modify(int cmd, unsigned int flags, int argc, char **argv
 	char *ptypep = NULL;
 	char *sctxp = NULL;
 	struct xfrm_userpolicy_type upt = {};
+	struct xfrm_user_offload xuo = {};
 	char tmpls_buf[XFRM_TMPLS_BUF_SIZE] = {};
 	int tmpls_len = 0;
 	struct xfrm_mark mark = {0, 0};
@@ -268,6 +270,8 @@ static int xfrm_policy_modify(int cmd, unsigned int flags, int argc, char **argv
 		char	str[CTX_BUF_SIZE];
 	} ctx = {};
 	bool is_if_id_set = false;
+	unsigned int ifindex = 0;
+	bool is_offload = false;
 	__u32 if_id = 0;
 
 	while (argc > 0) {
@@ -342,6 +346,21 @@ static int xfrm_policy_modify(int cmd, unsigned int flags, int argc, char **argv
 			if (get_u32(&if_id, *argv, 0))
 				invarg("IF_ID value is invalid", *argv);
 			is_if_id_set = true;
+		} else if (strcmp(*argv, "offload") == 0) {
+			NEXT_ARG();
+			if (strcmp(*argv, "packet") == 0)
+				NEXT_ARG();
+			else
+				invarg("Invalid offload mode", *argv);
+
+			if (strcmp(*argv, "dev") == 0) {
+				NEXT_ARG();
+				ifindex = ll_name_to_index(*argv);
+				if (!ifindex)
+					invarg("Invalid device name", *argv);
+			} else
+				invarg("Missing dev keyword", *argv);
+			is_offload = true;
 		} else {
 			if (selp)
 				duparg("unknown", *argv);
@@ -387,6 +406,13 @@ static int xfrm_policy_modify(int cmd, unsigned int flags, int argc, char **argv
 	if (is_if_id_set)
 		addattr32(&req.n, sizeof(req.buf), XFRMA_IF_ID, if_id);
 
+	if (is_offload) {
+		xuo.ifindex = ifindex;
+		xuo.flags |= XFRM_OFFLOAD_PACKET;
+		addattr_l(&req.n, sizeof(req.buf), XFRMA_OFFLOAD_DEV, &xuo,
+			  sizeof(xuo));
+	}
+
 	if (rtnl_open_byproto(&rth, 0, NETLINK_XFRM) < 0)
 		exit(1);
 

man/man8/ip-xfrm.8

@@ -252,6 +252,10 @@ ip-xfrm \- transform configuration
 .IR FLAG-LIST " ]"
 .RB "[ " if_id
 .IR IF-ID " ]"
+.RB "[ " offload
+.RB packet
+.RB dev
+.IR DEV " ]"
 .RI "[ " LIMIT-LIST " ] [ " TMPL-LIST " ]"
 
 .ti -8
@@ -593,6 +597,10 @@ of the packets emitted by the state
 .I IF-ID
 xfrm interface identifier used to in both xfrm policies and states
 
+.TP
+.I DEV
+Network interface name used to offload policies and states
+
 .sp
 .PP
 .TS