iproute_lwtunnel: fix JSON output

The same tag "dst" was being used for both the route destination
and the encap destination. This made it hard for JSON parsers.
Change to put the per-encap information under a nested JSON
object (similar to ip link type info).

Original output
[ {
        "dst": "192.168.11.0/24",
        "encap": "ip6",
        "id": 0,
        "src": "::",
        "dst": "fd00::c0a8:2dd",
        "hoplimit": 0,
        "tc": 0,
        "protocol": "5",
        "scope": "link",
        "flags": [ ]
    } ]

Revised output
[ {
        "dst": "192.168.11.0/24",
        "encap": {
            "encap_type": "ip6",
            "id": 0,
            "src": "::",
            "dst": "fd00::c0a8:2dd",
            "hoplimit": 0,
            "tc": 0
        },
        "protocol": "5",
        "scope": "link",
        "flags": [ ]
    } ]

Reported-by: Lars Ekman <uablrek@gmail.com>
Fixes: 663c3cb23103 ("iproute: implement JSON and color output")
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>

diff --git a/ip/iproute_lwtunnel.c b/ip/iproute_lwtunnel.c
index 8b7f3742b71e33b90cb9df12cc8bc7cf45ed7b20..9fcbdeac3e77b3530d4c2cf2fb74b43dcfdb8a23 100644 (file)
--- a/ip/iproute_lwtunnel.c
+++ b/ip/iproute_lwtunnel.c
@@ -840,8 +840,9 @@ void lwt_print_encap(FILE *fp, struct rtattr *encap_type,
                return;
 
        et = rta_getattr_u16(encap_type);
-
-       print_string(PRINT_ANY, "encap", " encap %s ", format_encap_type(et));
+       open_json_object("encap");
+       print_string(PRINT_ANY, "encap_type", " encap %s ",
+                    format_encap_type(et));
 
        switch (et) {
        case LWTUNNEL_ENCAP_MPLS:
@@ -875,6 +876,7 @@ void lwt_print_encap(FILE *fp, struct rtattr *encap_type,
                print_encap_xfrm(fp, encap);
                break;
        }
+       close_json_object();
 }
 
 static struct ipv6_sr_hdr *parse_srh(char *segbuf, int hmac, bool encap)