ss: Distinguish between IPv4 and IPv6 wildcard sockets

Commit aba9c23a6e1cb ("ss: enclose IPv6 address in brackets") unified
display of wildcard sockets in IPv4 and IPv6 to print the unspecified
address as '*'. Users then complained that they can't distinguish
between address families anymore, so change this again to what Stephen
Hemminger suggested:

| *:80    << both IPV6 and IPV4
| [::]:80 << IPV6_ONLY
| 0.0.0.0:80  << IPV4_ONLY

Note that on older kernels which don't support INET_DIAG_SKV6ONLY
attribute, pure IPv6 sockets will still show as '*'.

Cc: Humberto Alves <hjalves@live.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Phil Sutter <phil@nwl.cc>

diff --git a/misc/ss.c b/misc/ss.c
index 09bff8a7e2d2804d66f55dfe03541eebbe707e45..e37aba6022eb4293b525fe1240c8cf8dbc1de7a1 100644 (file)
--- a/misc/ss.c
+++ b/misc/ss.c
@@ -1041,7 +1041,8 @@ do_numeric:
        return buf;
 }
 
-static void inet_addr_print(const inet_prefix *a, int port, unsigned int ifindex)
+static void inet_addr_print(const inet_prefix *a, int port,
+                           unsigned int ifindex, bool v6only)
 {
        char buf[1024];
        const char *ap = buf;
@@ -1049,14 +1050,10 @@ static void inet_addr_print(const inet_prefix *a, int port, unsigned int ifindex
        const char *ifname = NULL;
 
        if (a->family == AF_INET) {
-               if (a->data[0] == 0) {
-                       buf[0] = '*';
-                       buf[1] = 0;
-               } else {
-                       ap = format_host(AF_INET, 4, a->data);
-               }
+               ap = format_host(AF_INET, 4, a->data);
        } else {
-               if (!memcmp(a->data, &in6addr_any, sizeof(in6addr_any))) {
+               if (!v6only &&
+                   !memcmp(a->data, &in6addr_any, sizeof(in6addr_any))) {
                        buf[0] = '*';
                        buf[1] = 0;
                } else {
@@ -1728,12 +1725,12 @@ static void proc_ctx_print(struct sockstat *s)
        }
 }
 
-static void inet_stats_print(struct sockstat *s)
+static void inet_stats_print(struct sockstat *s, bool v6only)
 {
        sock_state_print(s);
 
-       inet_addr_print(&s->local, s->lport, s->iface);
-       inet_addr_print(&s->remote, s->rport, 0);
+       inet_addr_print(&s->local, s->lport, s->iface, v6only);
+       inet_addr_print(&s->remote, s->rport, 0, v6only);
 
        proc_ctx_print(s);
 }
@@ -2065,7 +2062,7 @@ static int tcp_show_line(char *line, const struct filter *f, int family)
        s.rto       = s.rto != 3 * hz  ? s.rto / hz : 0;
        s.ss.type   = IPPROTO_TCP;
 
-       inet_stats_print(&s.ss);
+       inet_stats_print(&s.ss, false);
 
        if (show_options)
                tcp_timer_print(&s);
@@ -2411,6 +2408,7 @@ static int inet_show_sock(struct nlmsghdr *nlh,
 {
        struct rtattr *tb[INET_DIAG_MAX+1];
        struct inet_diag_msg *r = NLMSG_DATA(nlh);
+       unsigned char v6only = 0;
 
        parse_rtattr(tb, INET_DIAG_MAX, (struct rtattr *)(r+1),
                     nlh->nlmsg_len - NLMSG_LENGTH(sizeof(*r)));
@@ -2418,7 +2416,10 @@ static int inet_show_sock(struct nlmsghdr *nlh,
        if (tb[INET_DIAG_PROTOCOL])
                s->type = rta_getattr_u8(tb[INET_DIAG_PROTOCOL]);
 
-       inet_stats_print(s);
+       if (s->local.family == AF_INET6 && tb[INET_DIAG_SKV6ONLY])
+               v6only = rta_getattr_u8(tb[INET_DIAG_SKV6ONLY]);
+
+       inet_stats_print(s, v6only);
 
        if (show_options) {
                struct tcpstat t = {};
@@ -2434,12 +2435,9 @@ static int inet_show_sock(struct nlmsghdr *nlh,
 
        if (show_details) {
                sock_details_print(s);
-               if (s->local.family == AF_INET6 && tb[INET_DIAG_SKV6ONLY]) {
-                       unsigned char v6only;
-
-                       v6only = rta_getattr_u8(tb[INET_DIAG_SKV6ONLY]);
+               if (s->local.family == AF_INET6 && tb[INET_DIAG_SKV6ONLY])
                        printf(" v6only:%u", v6only);
-               }
+
                if (tb[INET_DIAG_SHUTDOWN]) {
                        unsigned char mask;
 
@@ -2910,7 +2908,7 @@ static int dgram_show_line(char *line, const struct filter *f, int family)
                opt[0] = 0;
 
        s.type = dg_proto == UDP_PROTO ? IPPROTO_UDP : 0;
-       inet_stats_print(&s);
+       inet_stats_print(&s, false);
 
        if (show_details && opt[0])
                printf(" opt:\"%s\"", opt);