mctp, mctp-netlink: allow add & remove of range routes

Add a separate parser for the route target argument, allowing
<min>-<max> ranges to be specified, and pass to the rtm_dst_len value of
the netlink rtmsg.

Fixes: #58

Signed-off-by: Jeremy Kerr <[email protected]>

Author: jk-ozlabs

CHANGELOG.md

@@ -37,6 +37,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 6. `mctp` now supports gateway routes
 
+7. `mctp` route can add & delete range routes, using a <min>-<max> range format
+
 ### Changed
 
 1. tests are now run with address sanitizer enabled (-fsanitize=address)

README.md

@@ -52,10 +52,10 @@ Use `mctp help` for the list of available commands:
 
     mctp route
     mctp route show [net <network>]
-    mctp route add <eid> via <dev> [mtu <mtu>]
-    mctp route add <eid> gw <eid> [net <net>] [mtu <mtu>]
-    mctp route del <eid> via <dev>
-    mctp route del <eid> gw <eid> [net <net>]
+    mctp route add <eid>[-<eid>] via <dev> [mtu <mtu>]
+    mctp route add <eid>[-<eid>] gw <eid> [net <net>] [mtu <mtu>]
+    mctp route del <eid>[-<eid>] via <dev>
+    mctp route del <eid>[-<eid>] gw <eid> [net <net>]
 
     mctp neigh
     mctp neigh show [dev <network>]

src/mctp-netlink.c

@@ -1250,7 +1250,7 @@ struct mctp_rtalter_msg {
 };
 static int fill_rtalter_args(struct mctp_nl *nl, struct mctp_rtalter_msg *msg,
 			     struct rtattr **prta, size_t *prta_len,
-			     mctp_eid_t eid, int ifindex,
+			     mctp_eid_t eid, unsigned int extent, int ifindex,
 			     const struct mctp_fq_addr *gw)
 {
 	struct rtattr *rta;
@@ -1261,27 +1261,31 @@ static int fill_rtalter_args(struct mctp_nl *nl, struct mctp_rtalter_msg *msg,
 		return -1;
 	}
 
+	if (extent > 0xff || (unsigned int)eid + extent > 0xfe) {
+		warnx("invalid route extent");
+		return -1;
+	}
+
 	memset(msg, 0x0, sizeof(*msg));
 	msg->nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
 
 	msg->rtmsg.rtm_family = AF_MCTP;
 	msg->rtmsg.rtm_type = RTN_UNICAST;
-	// TODO add eid range handling
-	msg->rtmsg.rtm_dst_len = 0;
+	msg->rtmsg.rtm_dst_len = extent;
 	msg->rtmsg.rtm_type = RTN_UNICAST;
 
 	msg->nh.nlmsg_len = NLMSG_LENGTH(sizeof(msg->rtmsg));
 	rta_len = sizeof(msg->rta_buff);
 	rta = (void *)msg->rta_buff;
 
-	msg->nh.nlmsg_len += mctp_put_rtnlmsg_attr(&rta, &rta_len,
-		RTA_DST, &eid, sizeof(eid));
+	msg->nh.nlmsg_len += mctp_put_rtnlmsg_attr(&rta, &rta_len, RTA_DST,
+						   &eid, sizeof(eid));
 	if (ifindex) {
-		msg->nh.nlmsg_len += mctp_put_rtnlmsg_attr(&rta, &rta_len,
-			RTA_OIF, &ifindex, sizeof(ifindex));
+		msg->nh.nlmsg_len += mctp_put_rtnlmsg_attr(
+			&rta, &rta_len, RTA_OIF, &ifindex, sizeof(ifindex));
 	} else {
-		msg->nh.nlmsg_len += mctp_put_rtnlmsg_attr(&rta, &rta_len,
-			RTA_GATEWAY, gw, sizeof(*gw));
+		msg->nh.nlmsg_len += mctp_put_rtnlmsg_attr(
+			&rta, &rta_len, RTA_GATEWAY, gw, sizeof(*gw));
 	}
 
 	if (prta)
@@ -1292,15 +1296,16 @@ static int fill_rtalter_args(struct mctp_nl *nl, struct mctp_rtalter_msg *msg,
 	return 0;
 }
 
-int mctp_nl_route_add(struct mctp_nl *nl, uint8_t eid, int ifindex,
-		      const struct mctp_fq_addr *gw, uint32_t mtu)
+int mctp_nl_route_add(struct mctp_nl *nl, uint8_t eid, unsigned int extent,
+		      int ifindex, const struct mctp_fq_addr *gw, uint32_t mtu)
 {
 	struct mctp_rtalter_msg msg;
 	struct rtattr *rta;
 	size_t rta_len;
 	int rc;
 
-	rc = fill_rtalter_args(nl, &msg, &rta, &rta_len, eid, ifindex, gw);
+	rc = fill_rtalter_args(nl, &msg, &rta, &rta_len, eid, extent, ifindex,
+			       gw);
 	if (rc) {
 		return -1;
 	}
@@ -1329,13 +1334,13 @@ int mctp_nl_route_add(struct mctp_nl *nl, uint8_t eid, int ifindex,
 	return mctp_nl_send(nl, &msg.nh);
 }
 
-int mctp_nl_route_del(struct mctp_nl *nl, uint8_t eid, int ifindex,
-		      const struct mctp_fq_addr *gw)
+int mctp_nl_route_del(struct mctp_nl *nl, uint8_t eid, unsigned int extent,
+		      int ifindex, const struct mctp_fq_addr *gw)
 {
 	struct mctp_rtalter_msg msg;
 	int rc;
 
-	rc = fill_rtalter_args(nl, &msg, NULL, NULL, eid, ifindex, gw);
+	rc = fill_rtalter_args(nl, &msg, NULL, NULL, eid, extent, ifindex, gw);
 	if (rc) {
 		return rc;
 	}

src/mctp-netlink.h

@@ -108,10 +108,10 @@ int mctp_nl_addr_add(struct mctp_nl *nl, uint8_t eid, int ifindex);
 int mctp_nl_addr_del(struct mctp_nl *nl, uint8_t eid, int ifindex);
 
 /* MCTP route helper */
-int mctp_nl_route_add(struct mctp_nl *nl, uint8_t eid, int ifindex,
-		      const struct mctp_fq_addr *gw, uint32_t mtu);
-int mctp_nl_route_del(struct mctp_nl *nl, uint8_t eid, int ifindex,
-		      const struct mctp_fq_addr *gw);
+int mctp_nl_route_add(struct mctp_nl *nl, uint8_t eid, unsigned int extent,
+		      int ifindex, const struct mctp_fq_addr *gw, uint32_t mtu);
+int mctp_nl_route_del(struct mctp_nl *nl, uint8_t eid, unsigned int extent,
+		      int ifindex, const struct mctp_fq_addr *gw);
 
 /* Helpers */
 

src/mctp.c

@@ -872,24 +872,73 @@ static int cmd_route_show(struct ctx *ctx, int argc, const char **argv)
 	return 0;
 }
 
+/* Parses a "min-max" eid range, or a single eid, into *eid and *extent.
+ * If a single EID is given, *extent will be zero. Returns -1 on failure.
+ */
+static int parse_eid_range(const char *str, mctp_eid_t *eid,
+			   unsigned int *extent)
+{
+	char tmp[10]; /* sufficient length to handle "100-101" */
+	mctp_eid_t min, max;
+	size_t len;
+	char *sep;
+	int rc;
+
+	len = strlen(str);
+	if (len >= sizeof(tmp) - 1)
+		return -1;
+
+	strncpy(tmp, str, sizeof(tmp) - 1);
+	tmp[sizeof(tmp) - 1] = '\0';
+
+	sep = strchr(tmp, '-');
+	if (sep) {
+		rc = parse_eid(sep + 1, &max);
+		if (rc)
+			return rc;
+
+		if (max >= 0xff)
+			return -1;
+
+		*sep = '\0';
+	}
+
+	rc = parse_eid(tmp, &min);
+	if (rc)
+		return rc;
+
+	*eid = min;
+	if (sep) {
+		if (max < min)
+			return -1;
+		*extent = max - min;
+	} else {
+		*extent = 0;
+	}
+
+	return 0;
+}
+
 static int parse_route_args(struct ctx *ctx, int argc, const char **argv,
-			    mctp_eid_t *eidp, int *ifindexp,
-			    struct mctp_fq_addr *gwp, unsigned int *mtup)
+			    mctp_eid_t *eidp, unsigned int *extentp,
+			    int *ifindexp, struct mctp_fq_addr *gwp,
+			    unsigned int *mtup)
 {
 	const char *eidstr, *linkstr = NULL;
 	struct mctp_fq_addr gw = { 0 };
 	bool have_net = false;
 	unsigned int mtu = 0;
 	int ifindex = 0, rc;
+	unsigned int extent;
 	mctp_eid_t eid;
 
 	if (argc < 3 || !(argc % 2))
 		return -1;
 
 	eidstr = argv[0];
-	rc = parse_eid(eidstr, &eid);
+	rc = parse_eid_range(eidstr, &eid, &extent);
 	if (rc) {
-		warnx("Invalid EID '%s'", eidstr);
+		warnx("Invalid EID/range '%s'", eidstr);
 		return -1;
 	}
 
@@ -949,6 +998,7 @@ static int parse_route_args(struct ctx *ctx, int argc, const char **argv,
 	}
 
 	*eidp = eid;
+	*extentp = extent;
 	*ifindexp = ifindex;
 	*gwp = gw;
 	*mtup = mtu;
@@ -959,34 +1009,37 @@ static int parse_route_args(struct ctx *ctx, int argc, const char **argv,
 static int cmd_route_add(struct ctx *ctx, int argc, const char **argv)
 {
 	struct mctp_fq_addr gw = { 0 };
-	uint32_t mtu = 0;
 	int rc, ifindex = 0;
+	unsigned int extent;
+	uint32_t mtu = 0;
 	mctp_eid_t eid;
 
-	rc = parse_route_args(ctx, argc - 1, argv + 1, &eid, &ifindex, &gw, &mtu);
+	rc = parse_route_args(ctx, argc - 1, argv + 1, &eid, &extent, &ifindex,
+			      &gw, &mtu);
 	if (rc) {
 		warnx("add: invalid command line arguments");
 		return -1;
 	}
 
-	return mctp_nl_route_add(ctx->nl, eid, ifindex, &gw, mtu);
+	return mctp_nl_route_add(ctx->nl, eid, extent, ifindex, &gw, mtu);
 }
 
 static int cmd_route_del(struct ctx *ctx, int argc, const char **argv)
 {
 	struct mctp_fq_addr gw = { 0 };
-	unsigned int mtu = 0;
+	unsigned int extent, mtu = 0;
 	int ifindex = 0;
 	mctp_eid_t eid;
 	int rc;
 
-	rc = parse_route_args(ctx, argc - 1, argv + 1, &eid, &ifindex, &gw, &mtu);
+	rc = parse_route_args(ctx, argc - 1, argv + 1, &eid, &extent, &ifindex,
+			      &gw, &mtu);
 	if (rc) {
 		warnx("del: invalid command line arguments");
 		return -1;
 	}
 
-	return mctp_nl_route_del(ctx->nl, eid, ifindex, &gw);
+	return mctp_nl_route_del(ctx->nl, eid, extent, ifindex, &gw);
 }
 
 static int cmd_route(struct ctx *ctx, int argc, const char **argv)
@@ -996,12 +1049,16 @@ static int cmd_route(struct ctx *ctx, int argc, const char **argv)
 		fprintf(stderr, "%s route\n", ctx->top_cmd);
 		fprintf(stderr, "%s route show [net <network>]\n",
 			ctx->top_cmd);
-		fprintf(stderr, "%s route add <eid> via <dev> [mtu <mtu>]\n",
+		fprintf(stderr,
+			"%s route add <eid>[-<eid>] via <dev> [mtu <mtu>]\n",
 			ctx->top_cmd);
-		fprintf(stderr, "%s route add <eid> gw <eid> [net <net>] [mtu <mtu>]\n",
+		fprintf(stderr,
+			"%s route add <eid>[-<eid>] gw <eid> [net <net>] [mtu <mtu>]\n",
+			ctx->top_cmd);
+		fprintf(stderr, "%s route del <eid>[-<eid>] via <dev>\n",
 			ctx->top_cmd);
-		fprintf(stderr, "%s route del <eid> via <dev>\n", ctx->top_cmd);
-		fprintf(stderr, "%s route del <eid> gw <eid> [net <net>]\n",
+		fprintf(stderr,
+			"%s route del <eid>[-<eid>] gw <eid> [net <net>]\n",
 			ctx->top_cmd);
 		return 255;
 	}

src/mctpd.c

@@ -1601,15 +1601,16 @@ static int peer_set_mtu(struct ctx *ctx, struct peer *peer, uint32_t mtu)
 		return -EPROTO;
 	}
 
-	rc = mctp_nl_route_del(ctx->nl, peer->eid, peer->phys.ifindex, NULL);
+	rc = mctp_nl_route_del(ctx->nl, peer->eid, 0, peer->phys.ifindex, NULL);
 	if (rc < 0 && rc != -ENOENT) {
 		warnx("%s, Failed removing existing route for eid %d %s",
 		      __func__, peer->phys.ifindex,
 		      mctp_nl_if_byindex(ctx->nl, peer->phys.ifindex));
 		// Continue regardless, route_add will likely fail with EEXIST
 	}
 
-	rc = mctp_nl_route_add(ctx->nl, peer->eid, peer->phys.ifindex, NULL, mtu);
+	rc = mctp_nl_route_add(ctx->nl, peer->eid, 0, peer->phys.ifindex, NULL,
+			       mtu);
 	if (rc >= 0) {
 		peer->mtu = mtu;
 	}
@@ -2323,10 +2324,10 @@ static int peer_route_update(struct peer *peer, uint16_t type)
 	}
 
 	if (type == RTM_NEWROUTE) {
-		return mctp_nl_route_add(peer->ctx->nl, peer->eid,
+		return mctp_nl_route_add(peer->ctx->nl, peer->eid, 0,
 					 peer->phys.ifindex, NULL, peer->mtu);
 	} else if (type == RTM_DELROUTE) {
-		return mctp_nl_route_del(peer->ctx->nl, peer->eid,
+		return mctp_nl_route_del(peer->ctx->nl, peer->eid, 0,
 					 peer->phys.ifindex, NULL);
 	}