From 0ddd7de1bac5e6c2546b9c150f7aa7e838a7d36b Mon Sep 17 00:00:00 2001
From: sg <goldsimon@gmx.de>
Date: Fri, 6 Mar 2015 21:30:59 +0100
Subject: [PATCH] patch #8359 (Provide utility function to add an IPv6 address
 to an interface)

---
 CHANGELOG                |  4 ++++
 src/core/netif.c         | 32 ++++++++++++++++++++++++++++++++
 src/include/lwip/netif.h |  1 +
 3 files changed, 37 insertions(+)

diff --git a/CHANGELOG b/CHANGELOG
index 3163d810..2debd2ff 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -6,6 +6,10 @@ HISTORY
 
   ++ New features:
 
+  2015-03-06: Philip Gladstone
+  * netif.h/.c: patch #8359 (Provide utility function to add an IPv6 address to
+    an interface)
+
   2015-03-05: Simon Goldschmidt
   * netif.c, ip4.c, dhcp.c, autoip.c: fixed bug #37068 (netif up/down handling
     is unclear): correclty separated administrative status of a netif (up/down)
diff --git a/src/core/netif.c b/src/core/netif.c
index 3dc8dc9b..bd6d56e2 100644
--- a/src/core/netif.c
+++ b/src/core/netif.c
@@ -916,6 +916,38 @@ netif_create_ip6_linklocal_address(struct netif * netif, u8_t from_mac_48bit)
 #endif /* LWIP_IPV6_AUTOCONFIG */
 }
 
+err_t
+netif_add_ip6_address(struct netif *netif, ip6_addr_t * ip6addr, s8_t *chosen_idx)
+{
+  s8_t i;
+
+  i = netif_get_ip6_addr_match(netif, ip6addr);
+  if (i >= 0) {
+    /* Address already added */
+    if (chosen_idx != NULL) {
+      *chosen_idx = i;
+    }
+    return ERR_OK;
+  }
+
+  /* Find a free slot -- musn't be the first one (reserved for link local) */
+  for (i = 1; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
+    if (!ip6_addr_isvalid(netif->ip6_addr_state[i])) {
+      ip6_addr_copy(netif->ip6_addr[i], *ip6addr);
+      netif_ip6_addr_set_state(netif, i, IP6_ADDR_TENTATIVE);
+      if (chosen_idx != NULL) {
+        *chosen_idx = i;
+      }
+      return ERR_OK;
+    }
+  }
+
+  if (chosen_idx != NULL) {
+    *chosen_idx = -1;
+  }
+  return ERR_VAL;
+}
+
 static err_t
 netif_null_output_ip6(struct netif *netif, struct pbuf *p, const ip6_addr_t *ipaddr)
 {
diff --git a/src/include/lwip/netif.h b/src/include/lwip/netif.h
index fe71beb6..0b6afc23 100644
--- a/src/include/lwip/netif.h
+++ b/src/include/lwip/netif.h
@@ -375,6 +375,7 @@ void netif_poll_all(void);
 #define netif_ip6_addr_set_state(netif, i, state)  ((netif)->ip6_addr_state[(i)] = (state))
 s8_t netif_get_ip6_addr_match(struct netif * netif, ip6_addr_t * ip6addr);
 void netif_create_ip6_linklocal_address(struct netif * netif, u8_t from_mac_48bit);
+err_t netif_add_ip6_address(struct netif *netif, ip6_addr_t *ip6addr, s8_t *chosen_idx);
 #endif /* LWIP_IPV6 */
 
 #if LWIP_NETIF_HWADDRHINT