xfrm: Allow replay setting

Hi Stephen:

[IP] xfrm: Allow replay setting

For certain applications there is a requirement to start the
sequence number from a point other than the default.  As it
is the kernel provides an interface to do that but it isn't
available through the ip(8) command.  Since we're encouraging
people to migrate over to ip(8) for manual keying, it is useful
to have this ability there.

This patch adds support for setting replay sequence numbers
through ip(8).
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Thanks,
--
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
--

ip/xfrm_state.c

@@ -57,7 +57,8 @@ static void usage(void)
 {
 	fprintf(stderr, "Usage: ip xfrm state { add | update } ID [ XFRM_OPT ] [ mode MODE ]\n");
 	fprintf(stderr, "        [ reqid REQID ] [ seq SEQ ] [ replay-window SIZE ] [ flag FLAG-LIST ]\n");
-	fprintf(stderr, "        [ encap ENCAP ] [ sel SELECTOR ] [ LIMIT-LIST ]\n");
+	fprintf(stderr, "        [ encap ENCAP ] [ sel SELECTOR ] [ replay-seq SEQ ]\n");
+	fprintf(stderr, "        [ replay-oseq SEQ ] [ LIMIT-LIST ]\n");
 	fprintf(stderr, "Usage: ip xfrm state allocspi ID [ mode MODE ] [ reqid REQID ] [ seq SEQ ]\n");
 	fprintf(stderr, "        [ min SPI max SPI ]\n");
 	fprintf(stderr, "Usage: ip xfrm state { delete | get } ID\n");
@@ -232,6 +233,7 @@ static int xfrm_state_modify(int cmd, unsigned flags, int argc, char **argv)
 		struct xfrm_usersa_info xsinfo;
 		char   			buf[RTA_BUF_SIZE];
 	} req;
+	struct xfrm_replay_state replay;
 	char *idp = NULL;
 	char *ealgop = NULL;
 	char *aalgop = NULL;
@@ -239,6 +241,7 @@ static int xfrm_state_modify(int cmd, unsigned flags, int argc, char **argv)
 	char *coap = NULL;
 
 	memset(&req, 0, sizeof(req));
+	memset(&replay, 0, sizeof(replay));
 
 	req.n.nlmsg_len = NLMSG_LENGTH(sizeof(req.xsinfo));
 	req.n.nlmsg_flags = NLM_F_REQUEST|flags;
@@ -264,6 +267,14 @@ static int xfrm_state_modify(int cmd, unsigned flags, int argc, char **argv)
 			NEXT_ARG();
 			if (get_u8(&req.xsinfo.replay_window, *argv, 0))
 				invarg("\"replay-window\" value is invalid", *argv);
+		} else if (strcmp(*argv, "replay-seq") == 0) {
+			NEXT_ARG();
+			if (get_u32(&replay.seq, *argv, 0))
+				invarg("\"replay-seq\" value is invalid", *argv);
+		} else if (strcmp(*argv, "replay-oseq") == 0) {
+			NEXT_ARG();
+			if (get_u32(&replay.oseq, *argv, 0))
+				invarg("\"replay-oseq\" value is invalid", *argv);
 		} else if (strcmp(*argv, "flag") == 0) {
 			NEXT_ARG();
 			xfrm_state_flag_parse(&req.xsinfo.flags, &argc, &argv);
@@ -386,6 +397,10 @@ static int xfrm_state_modify(int cmd, unsigned flags, int argc, char **argv)
 		argc--; argv++;
 	}
 
+	if (replay.seq || replay.oseq)
+		addattr_l(&req.n, sizeof(req.buf), XFRMA_REPLAY_VAL,
+			  (void *)&replay, sizeof(replay));
+
 	if (!idp) {
 		fprintf(stderr, "Not enough information: \"ID\" is required\n");
 		exit(1);