From 56ef320d6fed6676654a67097a6950d6868ce433 Mon Sep 17 00:00:00 2001
From: Zhe Weng <wengzhe@xiaomi.com>
Date: Wed, 25 Oct 2023 15:18:00 +0800
Subject: [PATCH] nshlib/ifconfig: Add support for add/del a single IPv6
 address

Note: We're using similar error codes as Linux:
```
linux> sudo ifconfig eth0 inet6 add fc00::2/64
linux> sudo ifconfig eth0 inet6 del fc00::2/112
SIOCDIFADDR: Cannot assign requested address
linux> sudo ifconfig eth0 inet6 del fc00::3/64
SIOCDIFADDR: Cannot assign requested address
linux> sudo ifconfig eth0 inet6 add fc00::2/64
SIOCSIFADDR: File exists

nuttx> ifconfig eth0 inet6 add fc00::2/64
nuttx> ifconfig eth0 inet6 del fc00::2/112
Failed to manage IPv6 address: Cannot assign requested address
nuttx> ifconfig eth0 inet6 del fc00::3/112
Failed to manage IPv6 address: Cannot assign requested address
nuttx> ifconfig eth0 inet6 add fc00::2/64
Failed to manage IPv6 address: File exists
```

Signed-off-by: Zhe Weng <wengzhe@xiaomi.com>
---
 nshlib/nsh_command.c |  2 +-
 nshlib/nsh_netcmds.c | 48 ++++++++++++++++++++++++++++++++++++++------
 2 files changed, 43 insertions(+), 7 deletions(-)

diff --git a/nshlib/nsh_command.c b/nshlib/nsh_command.c
index a1f5445d0..e4ce17a3d 100644
--- a/nshlib/nsh_command.c
+++ b/nshlib/nsh_command.c
@@ -278,7 +278,7 @@ static const struct cmdmap_s g_cmdmap[] =
 #ifdef CONFIG_NET
 #  ifndef CONFIG_NSH_DISABLE_IFCONFIG
   CMD_MAP("ifconfig", cmd_ifconfig, 1, 12,
-    "[interface [address_family] [mtu <len>] | [<ip-address>|dhcp]]"
+    "[interface [mtu <len>]|[address_family] [[add|del] <ip-address>|dhcp]]"
     "[dr|gw|gateway <dr-address>] [netmask <net-mask>|prefixlen <len>] "
     "[dns <dns-address>] [hw <hw-mac>]"),
 #  endif
diff --git a/nshlib/nsh_netcmds.c b/nshlib/nsh_netcmds.c
index e19841dc3..ddd2b7ea8 100644
--- a/nshlib/nsh_netcmds.c
+++ b/nshlib/nsh_netcmds.c
@@ -555,6 +555,9 @@ int cmd_ifconfig(FAR struct nsh_vtbl_s *vtbl, int argc, FAR char **argv)
   struct in6_addr addr6;
   struct in6_addr gip6 = IN6ADDR_ANY_INIT;
   FAR char *preflen = NULL;
+#  ifdef CONFIG_NETDEV_MULTIPLE_IPv6
+  bool remove = false;
+#  endif
 #endif
   int i;
   FAR char *ifname = NULL;
@@ -717,8 +720,14 @@ int cmd_ifconfig(FAR struct nsh_vtbl_s *vtbl, int argc, FAR char **argv)
 #endif
               else if (!strcmp(tmp, "add"))
                 {
-                  /* Compatible with linux IPv6 command, do nothing. */
-
+#if defined(CONFIG_NET_IPv6) && defined(CONFIG_NETDEV_MULTIPLE_IPv6)
+                  remove = false;
+                  continue;
+                }
+              else if (!strcmp(tmp, "del"))
+                {
+                  remove = true;
+#endif
                   continue;
                 }
               else if (!strcmp(tmp, "mtu"))
@@ -805,7 +814,9 @@ int cmd_ifconfig(FAR struct nsh_vtbl_s *vtbl, int argc, FAR char **argv)
           inet_pton(AF_INET6, hostip, &addr6);
         }
 
+#ifndef CONFIG_NETDEV_MULTIPLE_IPv6
       netlib_set_ipv6addr(ifname, &addr6);
+#endif
     }
 #endif /* CONFIG_NET_IPv6 */
 
@@ -899,23 +910,48 @@ int cmd_ifconfig(FAR struct nsh_vtbl_s *vtbl, int argc, FAR char **argv)
   if (inet6)
 #endif
     {
+      struct in6_addr mask6;
+#ifdef CONFIG_NETDEV_MULTIPLE_IPv6
+      uint8_t plen;
+#endif
       if (mask != NULL)
         {
           ninfo("Netmask: %s\n", mask);
-          inet_pton(AF_INET6, mask, &addr6);
+          inet_pton(AF_INET6, mask, &mask6);
         }
       else if (preflen != NULL)
         {
           ninfo("Prefixlen: %s\n", preflen);
-          netlib_prefix2ipv6netmask(atoi(preflen), &addr6);
+          netlib_prefix2ipv6netmask(atoi(preflen), &mask6);
         }
       else
         {
           ninfo("Netmask: Default\n");
-          inet_pton(AF_INET6, "ffff:ffff:ffff:ffff::", &addr6);
+          inet_pton(AF_INET6, "ffff:ffff:ffff:ffff::", &mask6);
         }
 
-      netlib_set_ipv6netmask(ifname, &addr6);
+#ifdef CONFIG_NETDEV_MULTIPLE_IPv6
+      plen = netlib_ipv6netmask2prefix(mask6.in6_u.u6_addr16);
+      if (remove)
+        {
+          ret = netlib_del_ipv6addr(ifname, &addr6, plen);
+        }
+      else
+        {
+          ret = netlib_add_ipv6addr(ifname, &addr6, plen);
+        }
+
+      if (ret < 0)
+        {
+          perror("Failed to manage IPv6 address");
+
+          /* REVISIT: Should we return ERROR or just let it go? */
+
+          return ERROR;
+        }
+#else
+      netlib_set_ipv6netmask(ifname, &mask6);
+#endif /* CONFIG_NETDEV_MULTIPLE_IPv6 */
     }
 #endif /* CONFIG_NET_IPv6 */