1 files changed, 78 insertions, 0 deletions

diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
index 8e29fb1d1df6..dc6695cc5767 100644
--- a/net/ipv6/ipv6_sockglue.c
+++ b/net/ipv6/ipv6_sockglue.c
@@ -617,7 +617,67 @@ done:
                 retv = xfrm_user_policy(sk, optname, optval, optlen);
                 break;
 
+        case IPV6_ADDR_PREFERENCES:
+            {
+                unsigned int pref = 0;
+                unsigned int prefmask = ~0;
+
+                retv = -EINVAL;
+
+                /* check PUBLIC/TMP/PUBTMP_DEFAULT conflicts */
+                switch (val & (IPV6_PREFER_SRC_PUBLIC|
+                               IPV6_PREFER_SRC_TMP|
+                               IPV6_PREFER_SRC_PUBTMP_DEFAULT)) {
+                case IPV6_PREFER_SRC_PUBLIC:
+                        pref |= IPV6_PREFER_SRC_PUBLIC;
+                        break;
+                case IPV6_PREFER_SRC_TMP:
+                        pref |= IPV6_PREFER_SRC_TMP;
+                        break;
+                case IPV6_PREFER_SRC_PUBTMP_DEFAULT:
+                        break;
+                case 0:
+                        goto pref_skip_pubtmp;
+                default:
+                        goto e_inval;
+                }
+
+                prefmask &= ~(IPV6_PREFER_SRC_PUBLIC|
+                              IPV6_PREFER_SRC_TMP);
+pref_skip_pubtmp:
+
+                /* check HOME/COA conflicts */
+                switch (val & (IPV6_PREFER_SRC_HOME|IPV6_PREFER_SRC_COA)) {
+                case IPV6_PREFER_SRC_HOME:
+                        break;
+                case IPV6_PREFER_SRC_COA:
+                        pref |= IPV6_PREFER_SRC_COA;
+                case 0:
+                        goto pref_skip_coa;
+                default:
+                        goto e_inval;
+                }
+
+                prefmask &= ~IPV6_PREFER_SRC_COA;
+pref_skip_coa:
+
+                /* check CGA/NONCGA conflicts */
+                switch (val & (IPV6_PREFER_SRC_CGA|IPV6_PREFER_SRC_NONCGA)) {
+                case IPV6_PREFER_SRC_CGA:
+                case IPV6_PREFER_SRC_NONCGA:
+                case 0:
+                        break;
+                default:
+                        goto e_inval;
+                }
+
+                np->srcprefs = (np->srcprefs & prefmask) | pref;
+                retv = 0;
+
+                break;
+            }
         }
+
         release_sock(sk);
 
         return retv;
@@ -932,6 +992,24 @@ static int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
                 val = np->sndflow;
                 break;
 
+        case IPV6_ADDR_PREFERENCES:
+                val = 0;
+
+                if (np->srcprefs & IPV6_PREFER_SRC_TMP)
+                        val |= IPV6_PREFER_SRC_TMP;
+                else if (np->srcprefs & IPV6_PREFER_SRC_PUBLIC)
+                        val |= IPV6_PREFER_SRC_PUBLIC;
+                else {
+                        /* XXX: should we return system default? */
+                        val |= IPV6_PREFER_SRC_PUBTMP_DEFAULT;
+                }
+
+                if (np->srcprefs & IPV6_PREFER_SRC_COA)
+                        val |= IPV6_PREFER_SRC_COA;
+                else
+                        val |= IPV6_PREFER_SRC_HOME;
+                break;
+
         default:
                 return -ENOPROTOOPT;
         }