Merge pull request #6730 from wesleycoakley/pbrd-dscp-ecn

DSCP / ECN-based PBR Matching

4 files changed, 165 insertions, 1 deletions

diff --git a/pbrd/pbr_map.c b/pbrd/pbr_map.c
index 0ef8432e5..10a75a9f5 100644
--- a/pbrd/pbr_map.c
+++ b/pbrd/pbr_map.c
@@ -444,6 +444,59 @@ static void pbr_map_add_interfaces(struct pbr_map *pbrm)
 	}
 }
 
+/* Decodes a standardized DSCP into its representative value */
+uint8_t pbr_map_decode_dscp_enum(const char *name)
+{
+	/* Standard Differentiated Services Field Codepoints */
+	if (!strcmp(name, "cs0"))
+		return 0;
+	if (!strcmp(name, "cs1"))
+		return 8;
+	if (!strcmp(name, "cs2"))
+		return 16;
+	if (!strcmp(name, "cs3"))
+		return 24;
+	if (!strcmp(name, "cs4"))
+		return 32;
+	if (!strcmp(name, "cs5"))
+		return 40;
+	if (!strcmp(name, "cs6"))
+		return 48;
+	if (!strcmp(name, "cs7"))
+		return 56;
+	if (!strcmp(name, "af11"))
+		return 10;
+	if (!strcmp(name, "af12"))
+		return 12;
+	if (!strcmp(name, "af13"))
+		return 14;
+	if (!strcmp(name, "af21"))
+		return 18;
+	if (!strcmp(name, "af22"))
+		return 20;
+	if (!strcmp(name, "af23"))
+		return 22;
+	if (!strcmp(name, "af31"))
+		return 26;
+	if (!strcmp(name, "af32"))
+		return 28;
+	if (!strcmp(name, "af33"))
+		return 30;
+	if (!strcmp(name, "af41"))
+		return 34;
+	if (!strcmp(name, "af42"))
+		return 36;
+	if (!strcmp(name, "af43"))
+		return 38;
+	if (!strcmp(name, "ef"))
+		return 46;
+	if (!strcmp(name, "voice-admit"))
+		return 44;
+
+	/* No match? Error out */
+	return -1;
+}
+
 struct pbr_map_sequence *pbrms_get(const char *name, uint32_t seqno)
 {
 	struct pbr_map *pbrm;
@@ -547,7 +600,7 @@ pbr_map_sequence_check_nexthops_valid(struct pbr_map_sequence *pbrms)
 
 static void pbr_map_sequence_check_not_empty(struct pbr_map_sequence *pbrms)
 {
-	if (!pbrms->src && !pbrms->dst && !pbrms->mark)
+	if (!pbrms->src && !pbrms->dst && !pbrms->mark && !pbrms->dsfield)
 		pbrms->reason |= PBR_MAP_INVALID_EMPTY;
 }
 
diff --git a/pbrd/pbr_map.h b/pbrd/pbr_map.h
index 704f1a036..64c090d2e 100644
--- a/pbrd/pbr_map.h
+++ b/pbrd/pbr_map.h
@@ -89,6 +89,7 @@ struct pbr_map_sequence {
 	 */
 	struct prefix *src;
 	struct prefix *dst;
+	uint8_t dsfield;
 	uint32_t mark;
 
 	/*
@@ -168,6 +169,8 @@ extern void pbr_map_add_interface(struct pbr_map *pbrm, struct interface *ifp);
 extern void pbr_map_interface_delete(struct pbr_map *pbrm,
 				     struct interface *ifp);
 
+extern uint8_t pbr_map_decode_dscp_enum(const char *name);
+
 /* Update maps installed on interface */
 extern void pbr_map_policy_interface_update(const struct interface *ifp,
 					    bool state_up);
diff --git a/pbrd/pbr_vty.c b/pbrd/pbr_vty.c
index cd9096cbc..a73d885ea 100644
--- a/pbrd/pbr_vty.c
+++ b/pbrd/pbr_vty.c
@@ -183,6 +183,91 @@ DEFPY(pbr_map_match_dst, pbr_map_match_dst_cmd,
 	return CMD_SUCCESS;
 }
 
+DEFPY(pbr_map_match_dscp, pbr_map_match_dscp_cmd,
+      "[no] match dscp DSCP$dscp",
+      NO_STR
+      "Match the rest of the command\n"
+      "Match based on IP DSCP field\n"
+      "DSCP value (below 64) or standard codepoint name\n")
+{
+	struct pbr_map_sequence *pbrms = VTY_GET_CONTEXT(pbr_map_sequence);
+	char dscpname[100];
+	uint8_t rawDscp;
+
+	/* Discriminate dscp enums (cs0, cs1 etc.) and numbers */
+	bool isANumber = true;
+	for (int i = 0; i < (int)strlen(dscp); i++) {
+		/* Letters are not numbers */
+		if (!isdigit(dscp[i]))
+			isANumber = false;
+
+		/* Lowercase the dscp enum (if needed) */
+		if (isupper(dscp[i]))
+			dscpname[i] = tolower(dscp[i]);
+		else
+			dscpname[i] = dscp[i];
+	}
+	dscpname[strlen(dscp)] = '\0';
+
+	if (isANumber) {
+		/* dscp passed is a regular number */
+		long dscpAsNum = strtol(dscp, NULL, 0);
+
+		if (dscpAsNum > PBR_DSFIELD_DSCP >> 2) {
+			/* Refuse to install on overflow */
+			vty_out(vty, "dscp (%s) must be less than 64\n", dscp);
+			return CMD_WARNING_CONFIG_FAILED;
+		}
+		rawDscp = dscpAsNum;
+	} else {
+		/* check dscp if it is an enum like cs0 */
+		rawDscp = pbr_map_decode_dscp_enum(dscpname);
+		if (rawDscp > PBR_DSFIELD_DSCP) {
+			vty_out(vty, "Invalid dscp value: %s\n", dscpname);
+			return CMD_WARNING_CONFIG_FAILED;
+		}
+	}
+
+	if (!no) {
+		if (((pbrms->dsfield & PBR_DSFIELD_DSCP) >> 2) == rawDscp)
+			return CMD_SUCCESS;
+
+		/* Set the DSCP bits of the DSField */
+		pbrms->dsfield =
+			(pbrms->dsfield & ~PBR_DSFIELD_DSCP) | (rawDscp << 2);
+	} else {
+		pbrms->dsfield &= ~PBR_DSFIELD_DSCP;
+	}
+
+	pbr_map_check(pbrms, true);
+
+	return CMD_SUCCESS;
+}
+
+DEFPY(pbr_map_match_ecn, pbr_map_match_ecn_cmd,
+      "[no] match ecn (0-3)$ecn",
+      NO_STR
+      "Match the rest of the command\n"
+      "Match based on IP ECN field\n"
+      "Explicit Congestion Notification\n")
+{
+	struct pbr_map_sequence *pbrms = VTY_GET_CONTEXT(pbr_map_sequence);
+
+	if (!no) {
+		if ((pbrms->dsfield & PBR_DSFIELD_ECN) == ecn)
+			return CMD_SUCCESS;
+
+		/* Set the ECN bits of the DSField */
+		pbrms->dsfield = (pbrms->dsfield & ~PBR_DSFIELD_ECN) | ecn;
+	} else {
+		pbrms->dsfield &= ~PBR_DSFIELD_ECN;
+	}
+
+	pbr_map_check(pbrms, true);
+
+	return CMD_SUCCESS;
+}
+
 DEFPY(pbr_map_match_mark, pbr_map_match_mark_cmd,
 	"[no] match mark (1-4294967295)$mark",
 	NO_STR
@@ -559,6 +644,12 @@ static void vty_show_pbrms(struct vty *vty,
 	if (pbrms->dst)
 		vty_out(vty, "        DST Match: %s\n",
 			prefix2str(pbrms->dst, buf, sizeof(buf)));
+	if (pbrms->dsfield & PBR_DSFIELD_DSCP)
+		vty_out(vty, "        DSCP Match: %u\n",
+			(pbrms->dsfield & PBR_DSFIELD_DSCP) >> 2);
+	if (pbrms->dsfield & PBR_DSFIELD_ECN)
+		vty_out(vty, "        ECN Match: %u\n",
+			pbrms->dsfield & PBR_DSFIELD_ECN);
 	if (pbrms->mark)
 		vty_out(vty, "        MARK Match: %u\n", pbrms->mark);
 
@@ -653,6 +744,12 @@ static void vty_json_pbrms(json_object *j, struct vty *vty,
 			prefix2str(pbrms->dst, buf, sizeof(buf)));
 	if (pbrms->mark)
 		json_object_int_add(jpbrm, "matchMark", pbrms->mark);
+	if (pbrms->dsfield & PBR_DSFIELD_DSCP)
+		json_object_int_add(jpbrm, "matchDscp",
+				    (pbrms->dsfield & PBR_DSFIELD_DSCP) >> 2);
+	if (pbrms->dsfield & PBR_DSFIELD_ECN)
+		json_object_int_add(jpbrm, "matchEcn",
+				    pbrms->dsfield & PBR_DSFIELD_ECN);
 
 	json_object_array_add(j, jpbrm);
 }
@@ -946,6 +1043,14 @@ static int pbr_vty_map_config_write_sequence(struct vty *vty,
 		vty_out(vty, " match dst-ip %s\n",
 			prefix2str(pbrms->dst, buff, sizeof(buff)));
 
+	if (pbrms->dsfield & PBR_DSFIELD_DSCP)
+		vty_out(vty, " match dscp %u\n",
+			(pbrms->dsfield & PBR_DSFIELD_DSCP) >> 2);
+
+	if (pbrms->dsfield & PBR_DSFIELD_ECN)
+		vty_out(vty, " match ecn %u\n",
+			pbrms->dsfield & PBR_DSFIELD_ECN);
+
 	if (pbrms->mark)
 		vty_out(vty, " match mark %u\n", pbrms->mark);
 
@@ -1026,6 +1131,8 @@ void pbr_vty_init(void)
 	install_element(INTERFACE_NODE, &pbr_policy_cmd);
 	install_element(PBRMAP_NODE, &pbr_map_match_src_cmd);
 	install_element(PBRMAP_NODE, &pbr_map_match_dst_cmd);
+	install_element(PBRMAP_NODE, &pbr_map_match_dscp_cmd);
+	install_element(PBRMAP_NODE, &pbr_map_match_ecn_cmd);
 	install_element(PBRMAP_NODE, &pbr_map_match_mark_cmd);
 	install_element(PBRMAP_NODE, &pbr_map_nexthop_group_cmd);
 	install_element(PBRMAP_NODE, &no_pbr_map_nexthop_group_cmd);
diff --git a/pbrd/pbr_zebra.c b/pbrd/pbr_zebra.c
index de2a99e26..d0099a46e 100644
--- a/pbrd/pbr_zebra.c
+++ b/pbrd/pbr_zebra.c
@@ -536,6 +536,7 @@ static void pbr_encode_pbr_map_sequence(struct stream *s,
 	stream_putw(s, 0);  /* src port */
 	pbr_encode_pbr_map_sequence_prefix(s, pbrms->dst, family);
 	stream_putw(s, 0);  /* dst port */
+	stream_putc(s, pbrms->dsfield);
 	stream_putl(s, pbrms->mark);
 
 	if (pbrms->vrf_unchanged || pbrms->vrf_lookup)