lib, pbrd: Move DSCP logic into a library module

Pull out all DSCP related code from PBR into a separate library module.
Relevant for route-maps used by the QPPB plugin.

Signed-off-by: Volodymyr Huti <[email protected]>

lib/dscp.c

@@ -0,0 +1,82 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * DSCP manipulation routines
+ * Copyright (C) 2023 VyOS Inc.
+ * Volodymyr Huti
+ */
+
+#include "dscp.h"
+
+enum dscp_val {
+	DSCP_CS0 = 0x00,
+	DSCP_CS1 = 0x08,
+	DSCP_CS2 = 0x10,
+	DSCP_CS3 = 0x18,
+	DSCP_CS4 = 0x20,
+	DSCP_CS5 = 0x28,
+	DSCP_CS6 = 0x30,
+	DSCP_CS7 = 0x38,
+	DSCP_AF11 = 0x0A,
+	DSCP_AF12 = 0x0C,
+	DSCP_AF13 = 0x0E,
+	DSCP_AF21 = 0x12,
+	DSCP_AF22 = 0x14,
+	DSCP_AF23 = 0x16,
+	DSCP_AF31 = 0x1A,
+	DSCP_AF32 = 0x1C,
+	DSCP_AF33 = 0x1E,
+	DSCP_AF41 = 0x22,
+	DSCP_AF42 = 0x34,
+	DSCP_AF43 = 0x26,
+	DSCP_EF = 0x2E,
+	DSCP_VOICE = 0x2C,
+	DSCP_MAX = DSCP_CS7 + 1,
+	DSCP_ERR
+};
+
+static const struct {
+	const char *name;
+	int val;
+} dscp_enum_int_map[] = {
+	{"cs0", DSCP_CS0},	    {"cs1", DSCP_CS1},	 {"cs2", DSCP_CS2},
+	{"cs3", DSCP_CS3},	    {"cs4", DSCP_CS4},	 {"cs5", DSCP_CS5},
+	{"cs6", DSCP_CS6},	    {"cs7", DSCP_CS7},	 {"af11", DSCP_AF11},
+	{"af12", DSCP_AF12},	    {"af13", DSCP_AF13}, {"af21", DSCP_AF21},
+	{"af22", DSCP_AF22},	    {"af23", DSCP_AF23}, {"af31", DSCP_AF31},
+	{"af32", DSCP_AF32},	    {"af33", DSCP_AF33}, {"af41", DSCP_AF41},
+	{"af42", DSCP_AF42},	    {"af43", DSCP_AF43}, {"ef", DSCP_EF},
+	{"voice-admit", DSCP_VOICE}};
+
+static const char *dscp_int_enum_map[DSCP_MAX] = {
+	[DSCP_CS0] = "cs0",	     [DSCP_CS1] = "cs1",   [DSCP_CS2] = "cs2",
+	[DSCP_CS3] = "cs3",	     [DSCP_CS4] = "cs4",   [DSCP_CS5] = "cs5",
+	[DSCP_CS6] = "cs6",	     [DSCP_CS7] = "cs7",   [DSCP_AF11] = "af11",
+	[DSCP_AF12] = "af12",	     [DSCP_AF13] = "af13", [DSCP_AF21] = "af21",
+	[DSCP_AF22] = "af22",	     [DSCP_AF23] = "af23", [DSCP_AF31] = "af31",
+	[DSCP_AF32] = "af32",	     [DSCP_AF33] = "af33", [DSCP_AF41] = "af41",
+	[DSCP_AF42] = "af42",	     [DSCP_AF43] = "af43", [DSCP_EF] = "ef",
+	[DSCP_VOICE] = "voice-admit"};
+
+static const int dscp_msize =
+	(sizeof(dscp_enum_int_map) / sizeof(*dscp_enum_int_map));
+
+/* Decodes a standardized DSCP into its representative value */
+uint8_t dscp_decode_enum(const char *name)
+{
+	int dscp_val = -1;
+
+	for (int i = 0; i < dscp_msize; ++i) {
+		if (!strcmp(dscp_enum_int_map[i].name, name)) {
+			dscp_val = dscp_enum_int_map[i].val;
+			break;
+		}
+	}
+
+	return dscp_val;
+}
+
+const char *dscp_enum_str(int dscp)
+{
+	return (dscp < DSCP_MAX) ? dscp_int_enum_map[dscp] : NULL;
+}
+

lib/dscp.h

@@ -0,0 +1,28 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * DSCP manipulation routines header
+ * Copyright (C) 2023 VyOS Inc.
+ * Volodymyr Huti
+ */
+
+#ifndef FRR_DSCP_H
+#define FRR_DSCP_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <zebra.h>
+#include "vty.h"
+
+#define DSFIELD_DSCP (0xfc) /* Upper 6 bits of DS field: DSCP */
+#define DSFIELD_ECN (0x03)  /* Lower 2 bits of DS field: BCN */
+
+extern uint8_t dscp_decode_enum(const char *dscp);
+extern const char *dscp_enum_str(int dscp);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* FRR_DSCP_H */

lib/pbr.h

@@ -43,9 +43,6 @@ struct pbr_filter {
 #define PBR_FILTER_VLAN_FLAGS     (1 << 11)
 #define PBR_FILTER_VLAN_ID        (1 << 12)
 
-#define PBR_DSFIELD_DSCP (0xfc) /* Upper 6 bits of DS field: DSCP */
-#define PBR_DSFIELD_ECN (0x03)	/* Lower 2 bits of DS field: BCN */
-
 #define PBR_PCP (0x07)		/* 3-bit value 0..7 for prioritization*/
 
 #define PBR_VLAN_FLAGS_NO_WILD	  0

lib/subdir.am

@@ -133,6 +133,7 @@ lib_libfrr_la_SOURCES = \
 	lib/printf/glue.c \
 	lib/routing_nb.c \
 	lib/routing_nb_config.c \
+	lib/dscp.c \
 	lib/tc.c \
 	# end
 

lib/zclient.c

@@ -28,6 +28,7 @@
 #include "srte.h"
 #include "printfrr.h"
 #include "srv6.h"
+#include "dscp.h"
 
 DEFINE_MTYPE_STATIC(LIB, ZCLIENT, "Zclient");
 DEFINE_MTYPE_STATIC(LIB, REDIST_INST, "Redistribution instance IDs");
@@ -1699,9 +1700,9 @@ static void zapi_pbr_rule_filter_encode(struct stream *s, struct pbr_filter *f)
 		stream_putw(s, f->dst_port);
 
 	if (CHECK_FLAG(f->filter_bm, PBR_FILTER_DSCP))
-		stream_putc(s, f->dsfield & PBR_DSFIELD_DSCP);
+		stream_putc(s, f->dsfield & DSFIELD_DSCP);
 	if (CHECK_FLAG(f->filter_bm, PBR_FILTER_ECN))
-		stream_putc(s, f->dsfield & PBR_DSFIELD_ECN);
+		stream_putc(s, f->dsfield & DSFIELD_ECN);
 
 	/* vlan */
 	if (CHECK_FLAG(f->filter_bm, PBR_FILTER_PCP))
@@ -1742,7 +1743,7 @@ static bool zapi_pbr_rule_filter_decode(struct stream *s, struct pbr_filter *f)
 		STREAM_GETC(s, dscp);
 	if (CHECK_FLAG(f->filter_bm, PBR_FILTER_ECN))
 		STREAM_GETC(s, ecn);
-	f->dsfield = (dscp & PBR_DSFIELD_DSCP) | (ecn & PBR_DSFIELD_ECN);
+	f->dsfield = (dscp & DSFIELD_DSCP) | (ecn & DSFIELD_ECN);
 
 	/* vlan */
 	if (CHECK_FLAG(f->filter_bm, PBR_FILTER_PCP))
@@ -1781,9 +1782,9 @@ static void zapi_pbr_rule_action_encode(struct stream *s, struct pbr_action *a)
 		stream_putw(s, a->dst_port);
 
 	if (CHECK_FLAG(a->flags, PBR_ACTION_DSCP))
-		stream_putc(s, a->dscp & PBR_DSFIELD_DSCP);
+		stream_putc(s, a->dscp & DSFIELD_DSCP);
 	if (CHECK_FLAG(a->flags, PBR_ACTION_ECN))
-		stream_putc(s, a->ecn & PBR_DSFIELD_ECN);
+		stream_putc(s, a->ecn & DSFIELD_ECN);
 
 	/* L2 */
 	if (CHECK_FLAG(a->flags, PBR_ACTION_PCP))
@@ -1817,11 +1818,11 @@ static bool zapi_pbr_rule_action_decode(struct stream *s, struct pbr_action *a)
 
 	if (CHECK_FLAG(a->flags, PBR_ACTION_DSCP)) {
 		STREAM_GETC(s, a->dscp);
-		a->dscp &= PBR_DSFIELD_DSCP;
+		a->dscp &= DSFIELD_DSCP;
 	}
 	if (CHECK_FLAG(a->flags, PBR_ACTION_ECN)) {
 		STREAM_GETC(s, a->ecn);
-		a->ecn &= PBR_DSFIELD_ECN;
+		a->ecn &= DSFIELD_ECN;
 	}
 
 	/* L2 */

pbrd/pbr_map.c

@@ -440,59 +440,6 @@ 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 = NULL;

pbrd/pbr_map.h

@@ -214,8 +214,6 @@ 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);

pbrd/pbr_vty.c

@@ -20,6 +20,7 @@
 #include "json.h"
 #include "debug.h"
 #include "pbr.h"
+#include "dscp.h"
 
 #include "pbrd/pbr_nht.h"
 #include "pbrd/pbr_map.h"
@@ -437,7 +438,7 @@ DEFPY  (pbr_map_match_dscp,
 		if (!CHECK_FLAG(pbrms->filter_bm, PBR_FILTER_DSCP))
 			return CMD_SUCCESS;
 		UNSET_FLAG(pbrms->filter_bm, PBR_FILTER_DSCP);
-		pbrms->dsfield &= ~PBR_DSFIELD_DSCP;
+		pbrms->dsfield &= ~DSFIELD_DSCP;
 		goto check;
 	}
 
@@ -448,23 +449,23 @@ DEFPY  (pbr_map_match_dscp,
 	assert(dscp);
 	ul_dscp = strtoul(dscp, &pend, 0);
 	if (pend && *pend)
-		ul_dscp = pbr_map_decode_dscp_enum(dscp);
+		ul_dscp = dscp_decode_enum(dscp);
 
-	if (ul_dscp > (PBR_DSFIELD_DSCP >> 2)) {
+	if (ul_dscp > (DSFIELD_DSCP >> 2)) {
 		vty_out(vty, "Invalid dscp value: %s%s\n", dscp,
 			((pend && *pend) ? "" : " (numeric value must be in range 0-63)"));
 		return CMD_WARNING_CONFIG_FAILED;
 	}
 
-	shifted_dscp = (ul_dscp << 2) & PBR_DSFIELD_DSCP;
+	shifted_dscp = (ul_dscp << 2) & DSFIELD_DSCP;
 
 	if (CHECK_FLAG(pbrms->filter_bm, PBR_FILTER_DSCP) &&
-	    ((pbrms->dsfield & PBR_DSFIELD_DSCP) == shifted_dscp)) {
+	    ((pbrms->dsfield & DSFIELD_DSCP) == shifted_dscp)) {
 		return CMD_SUCCESS;
 	}
 
 	/* Set the DSCP bits of the DSField */
-	pbrms->dsfield = (pbrms->dsfield & ~PBR_DSFIELD_DSCP) | shifted_dscp;
+	pbrms->dsfield = (pbrms->dsfield & ~DSFIELD_DSCP) | shifted_dscp;
 	SET_FLAG(pbrms->filter_bm, PBR_FILTER_DSCP);
 
 check:
@@ -491,17 +492,17 @@ DEFPY  (pbr_map_match_ecn,
 		if (!CHECK_FLAG(pbrms->filter_bm, PBR_FILTER_ECN))
 			return CMD_SUCCESS;
 		UNSET_FLAG(pbrms->filter_bm, PBR_FILTER_ECN);
-		pbrms->dsfield &= ~PBR_DSFIELD_ECN;
+		pbrms->dsfield &= ~DSFIELD_ECN;
 		goto check;
 	}
 
 	if (CHECK_FLAG(pbrms->filter_bm, PBR_FILTER_ECN) &&
-	    ((pbrms->dsfield & PBR_DSFIELD_ECN) == ecn)) {
+	    ((pbrms->dsfield & DSFIELD_ECN) == ecn)) {
 		return CMD_SUCCESS;
 	}
 
 	/* Set the ECN bits of the DSField */
-	pbrms->dsfield = (pbrms->dsfield & ~PBR_DSFIELD_ECN) | ecn;
+	pbrms->dsfield = (pbrms->dsfield & ~DSFIELD_ECN) | ecn;
 	SET_FLAG(pbrms->filter_bm, PBR_FILTER_ECN);
 
 check:
@@ -876,15 +877,15 @@ DEFPY  (pbr_map_action_dscp,
 	assert(dscp);
 	ul_dscp = strtoul(dscp, &pend, 0);
 	if (pend && *pend)
-		ul_dscp = pbr_map_decode_dscp_enum(dscp);
+		ul_dscp = dscp_decode_enum(dscp);
 
-	if (ul_dscp > (PBR_DSFIELD_DSCP >> 2)) {
+	if (ul_dscp > (DSFIELD_DSCP >> 2)) {
 		vty_out(vty, "Invalid dscp value: %s%s\n", dscp,
 			((pend && *pend) ? "" : " (numeric value must be in range 0-63)"));
 		return CMD_WARNING_CONFIG_FAILED;
 	}
 
-	shifted_dscp = (ul_dscp << 2) & PBR_DSFIELD_DSCP;
+	shifted_dscp = (ul_dscp << 2) & DSFIELD_DSCP;
 
 	if (CHECK_FLAG(pbrms->action_bm, PBR_ACTION_DSCP) &&
 	    (pbrms->action_dscp == shifted_dscp)) {
@@ -1549,10 +1550,10 @@ static void vty_show_pbrms(struct vty *vty,
 
 	if (CHECK_FLAG(pbrms->filter_bm, PBR_FILTER_DSCP))
 		vty_out(vty, "        DSCP Match: %u\n",
-			(pbrms->dsfield & PBR_DSFIELD_DSCP) >> 2);
+			(pbrms->dsfield & DSFIELD_DSCP) >> 2);
 	if (CHECK_FLAG(pbrms->filter_bm, PBR_FILTER_ECN))
 		vty_out(vty, "        ECN Match: %u\n",
-			pbrms->dsfield & PBR_DSFIELD_ECN);
+			pbrms->dsfield & DSFIELD_ECN);
 
 	if (CHECK_FLAG(pbrms->filter_bm, PBR_FILTER_FWMARK))
 		vty_out(vty, "        MARK Match: %u\n", pbrms->mark);
@@ -1717,11 +1718,10 @@ static void vty_json_pbrms(json_object *j, struct vty *vty,
 
 	if (CHECK_FLAG(pbrms->filter_bm, PBR_FILTER_DSCP))
 		json_object_int_add(jpbrm, "matchDscp",
-				    (pbrms->dsfield & PBR_DSFIELD_DSCP) >> 2);
+				    (pbrms->dsfield & DSFIELD_DSCP) >> 2);
 	if (CHECK_FLAG(pbrms->filter_bm, PBR_FILTER_ECN))
 		json_object_int_add(jpbrm, "matchEcn",
-				    pbrms->dsfield & PBR_DSFIELD_ECN);
-
+				    pbrms->dsfield & DSFIELD_ECN);
 	/* L2 headers */
 	if (CHECK_FLAG(pbrms->filter_bm, PBR_FILTER_PCP))
 		json_object_int_add(jpbrm, "matchPcp", pbrms->match_pcp);
@@ -2067,11 +2067,11 @@ static int pbr_vty_map_config_write_sequence(struct vty *vty,
 
 	if (CHECK_FLAG(pbrms->filter_bm, PBR_FILTER_DSCP))
 		vty_out(vty, " match dscp %u\n",
-			(pbrms->dsfield & PBR_DSFIELD_DSCP) >> 2);
+			(pbrms->dsfield & DSFIELD_DSCP) >> 2);
 
 	if (CHECK_FLAG(pbrms->filter_bm, PBR_FILTER_ECN))
 		vty_out(vty, " match ecn %u\n",
-			pbrms->dsfield & PBR_DSFIELD_ECN);
+			pbrms->dsfield & DSFIELD_ECN);
 
 	if (CHECK_FLAG(pbrms->filter_bm, PBR_FILTER_PCP))
 		vty_out(vty, " match pcp %d\n", pbrms->match_pcp);

tests/lib/cxxcompat.c

@@ -32,6 +32,7 @@
 #include "lib/if.h"
 #include "lib/if_rmap.h"
 #include "lib/imsg.h"
+#include "lib/dscp.h"
 #include "lib/ipaddr.h"
 #include "lib/jhash.h"
 #include "lib/json.h"