tc: pedit: Support JSON dumping

The action pedit does not currently support dumping to JSON. Convert
print_pedit() to the print_* family of functions so that dumping is correct
both in plain and JSON mode. In plain mode, the output is character for
character the same as it was before. In JSON mode, this is an example dump:

$ tc filter add dev dummy0 ingress prio 125 flower \
         action pedit ex munge udp dport set 12345 \
	                 munge ip ttl add 1        \
			 munge offset 10 u8 clear
$ tc -j filter show dev dummy0 ingress | jq
[
  {
    "protocol": "all",
    "pref": 125,
    "kind": "flower",
    "chain": 0
  },
  {
    "protocol": "all",
    "pref": 125,
    "kind": "flower",
    "chain": 0,
    "options": {
      "handle": 1,
      "keys": {},
      "not_in_hw": true,
      "actions": [
        {
          "order": 1,
          "kind": "pedit",
          "control_action": {
            "type": "pass"
          },
          "nkeys": 3,
          "index": 1,
          "ref": 1,
          "bind": 1,
          "keys": [
            {
              "htype": "udp",
              "offset": 0,
              "cmd": "set",
              "val": "3039",
              "mask": "ffff0000"
            },
            {
              "htype": "ipv4",
              "offset": 8,
              "cmd": "add",
              "val": "1000000",
              "mask": "ffffff"
            },
            {
              "htype": "network",
              "offset": 8,
              "cmd": "set",
              "val": "0",
              "mask": "ffff00ff"
            }
          ]
        }
      ]
    }
  }
]

Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David Ahern <dsahern@gmail.com>

1 files changed, 46 insertions, 25 deletions

diff --git a/tc/m_pedit.c b/tc/m_pedit.c
index fccfd17ca..51dcf1093 100644
--- a/tc/m_pedit.c
+++ b/tc/m_pedit.c
@@ -714,20 +714,28 @@ static const char * const pedit_htype_str[] = {
 	[TCA_PEDIT_KEY_EX_HDR_TYPE_UDP] = "udp",
 };
 
-static void print_pedit_location(FILE *f,
-				 enum pedit_header_type htype, __u32 off)
+static int print_pedit_location(FILE *f,
+				enum pedit_header_type htype, __u32 off)
 {
-	if (htype == TCA_PEDIT_KEY_EX_HDR_TYPE_NETWORK) {
-		fprintf(f, "%d", (unsigned int)off);
-		return;
+	char *buf = NULL;
+	int rc;
+
+	if (htype != TCA_PEDIT_KEY_EX_HDR_TYPE_NETWORK) {
+		if (htype < ARRAY_SIZE(pedit_htype_str))
+			rc = asprintf(&buf, "%s", pedit_htype_str[htype]);
+		else
+			rc = asprintf(&buf, "unknown(%d)", htype);
+		if (rc < 0)
+			return rc;
+		print_string(PRINT_ANY, "htype", "%s", buf);
+		print_int(PRINT_ANY, "offset", "%+d", off);
+	} else {
+		print_string(PRINT_JSON, "htype", NULL, "network");
+		print_int(PRINT_ANY, "offset", "%d", off);
 	}
 
-	if (htype < ARRAY_SIZE(pedit_htype_str))
-		fprintf(f, "%s", pedit_htype_str[htype]);
-	else
-		fprintf(f, "unknown(%d)", htype);
-
-	fprintf(f, "%c%d", (int)off  >= 0 ? '+' : '-', abs((int)off));
+	free(buf);
+	return 0;
 }
 
 static int print_pedit(struct action_util *au, FILE *f, struct rtattr *arg)
@@ -735,6 +743,7 @@ static int print_pedit(struct action_util *au, FILE *f, struct rtattr *arg)
 	struct tc_pedit_sel *sel;
 	struct rtattr *tb[TCA_PEDIT_MAX + 1];
 	struct m_pedit_key_ex *keys_ex = NULL;
+	int err;
 
 	if (arg == NULL)
 		return -1;
@@ -774,11 +783,12 @@ static int print_pedit(struct action_util *au, FILE *f, struct rtattr *arg)
 		}
 	}
 
-	fprintf(f, " pedit ");
+	print_string(PRINT_ANY, "kind", " %s ", "pedit");
 	print_action_control(f, "action ", sel->action, " ");
-	fprintf(f,"keys %d\n ", sel->nkeys);
-	fprintf(f, "\t index %u ref %d bind %d", sel->index, sel->refcnt,
-		sel->bindcnt);
+	print_uint(PRINT_ANY, "nkeys", "keys %d\n", sel->nkeys);
+	print_uint(PRINT_ANY, "index", " \t index %u", sel->index);
+	print_int(PRINT_ANY, "ref", " ref %d", sel->refcnt);
+	print_int(PRINT_ANY, "bind", " bind %d", sel->bindcnt);
 
 	if (show_stats) {
 		if (tb[TCA_PEDIT_TM]) {
@@ -787,6 +797,7 @@ static int print_pedit(struct action_util *au, FILE *f, struct rtattr *arg)
 			print_tm(f, tm);
 		}
 	}
+	open_json_array(PRINT_JSON, "keys");
 	if (sel->nkeys) {
 		int i;
 		struct tc_pedit_key *key = sel->keys;
@@ -804,21 +815,31 @@ static int print_pedit(struct action_util *au, FILE *f, struct rtattr *arg)
 				key_ex++;
 			}
 
-			fprintf(f, "\n\t key #%d", i);
-
-			fprintf(f, "  at ");
-
-			print_pedit_location(f, htype, key->off);
-
-			fprintf(f, ": %s %08x mask %08x",
-				cmd ? "add" : "val",
-				(unsigned int)ntohl(key->val),
-				(unsigned int)ntohl(key->mask));
+			open_json_object(NULL);
+			print_uint(PRINT_FP, NULL, "\n\t key #%d  at ", i);
+
+			err = print_pedit_location(f, htype, key->off);
+			if (err)
+				return err;
+
+			/* In FP, report the "set" command as "val" to keep
+			 * backward compatibility. Report the true name in JSON.
+			 */
+			print_string(PRINT_FP, NULL, ": %s",
+				     cmd ? "add" : "val");
+			print_string(PRINT_JSON, "cmd", NULL,
+				     cmd ? "add" : "set");
+			print_hex(PRINT_ANY, "val", " %08x",
+				  (unsigned int)ntohl(key->val));
+			print_hex(PRINT_ANY, "mask", " mask %08x",
+				  (unsigned int)ntohl(key->mask));
+			close_json_object();
 		}
 	} else {
 		fprintf(f, "\npedit %x keys %d is not LEGIT", sel->index,
 			sel->nkeys);
 	}
+	close_json_array(PRINT_JSON, " ");
 
 	print_nl();