Merge remote-tracking branch 'remotes/thibault/tags/samuel-thibault' into staging

slirp updates

# gpg: Signature made Tue 28 Mar 2017 23:51:51 BST
# gpg:                using RSA key 0xB0A51BF58C9179C5
# gpg: Good signature from "Samuel Thibault <samuel.thibault@aquilenet.fr>"
# gpg:                 aka "Samuel Thibault <sthibault@debian.org>"
# gpg:                 aka "Samuel Thibault <samuel.thibault@gnu.org>"
# gpg:                 aka "Samuel Thibault <samuel.thibault@inria.fr>"
# gpg:                 aka "Samuel Thibault <samuel.thibault@labri.fr>"
# gpg:                 aka "Samuel Thibault <samuel.thibault@ens-lyon.org>"
# gpg:                 aka "Samuel Thibault <samuel.thibault@u-bordeaux.fr>"
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg:          It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 900C B024 B679 31D4 0F82  304B D017 8C76 7D06 9EE6
#      Subkey fingerprint: AEBF 7448 FAB9 453A 4552  390E B0A5 1BF5 8C91 79C5

* remotes/thibault/tags/samuel-thibault:
  slirp: Send RDNSS in RA only if host has an IPv6 DNS server
  slirp: Make RA build more flexible
  slirp: fix compilation errors with DEBUG set

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

2 files changed, 23 insertions, 26 deletions

diff --git a/slirp/ip6_icmp.c b/slirp/ip6_icmp.c
index 298a48dd25..777eb574be 100644
--- a/slirp/ip6_icmp.c
+++ b/slirp/ip6_icmp.c
@@ -143,17 +143,13 @@ void ndp_send_ra(Slirp *slirp)
     /* Build IPv6 packet */
     struct mbuf *t = m_get(slirp);
     struct ip6 *rip = mtod(t, struct ip6 *);
+    size_t pl_size = 0;
+    struct in6_addr addr;
+    uint32_t scope_id;
+
     rip->ip_src = (struct in6_addr)LINKLOCAL_ADDR;
     rip->ip_dst = (struct in6_addr)ALLNODES_MULTICAST;
     rip->ip_nh = IPPROTO_ICMPV6;
-    rip->ip_pl = htons(ICMP6_NDP_RA_MINLEN
-                        + NDPOPT_LINKLAYER_LEN
-                        + NDPOPT_PREFIXINFO_LEN
-#ifndef _WIN32
-                        + NDPOPT_RDNSS_LEN
-#endif
-                        );
-    t->m_len = sizeof(struct ip6) + ntohs(rip->ip_pl);
 
     /* Build ICMPv6 packet */
     t->m_data += sizeof(struct ip6);
@@ -171,6 +167,7 @@ void ndp_send_ra(Slirp *slirp)
     ricmp->icmp6_nra.reach_time = htonl(NDP_AdvReachableTime);
     ricmp->icmp6_nra.retrans_time = htonl(NDP_AdvRetransTime);
     t->m_data += ICMP6_NDP_RA_MINLEN;
+    pl_size += ICMP6_NDP_RA_MINLEN;
 
     /* Source link-layer address (NDP option) */
     struct ndpopt *opt = mtod(t, struct ndpopt *);
@@ -178,6 +175,7 @@ void ndp_send_ra(Slirp *slirp)
     opt->ndpopt_len = NDPOPT_LINKLAYER_LEN / 8;
     in6_compute_ethaddr(rip->ip_src, opt->ndpopt_linklayer);
     t->m_data += NDPOPT_LINKLAYER_LEN;
+    pl_size += NDPOPT_LINKLAYER_LEN;
 
     /* Prefix information (NDP option) */
     struct ndpopt *opt2 = mtod(t, struct ndpopt *);
@@ -192,27 +190,26 @@ void ndp_send_ra(Slirp *slirp)
     opt2->ndpopt_prefixinfo.reserved2 = 0;
     opt2->ndpopt_prefixinfo.prefix = slirp->vprefix_addr6;
     t->m_data += NDPOPT_PREFIXINFO_LEN;
+    pl_size += NDPOPT_PREFIXINFO_LEN;
 
-#ifndef _WIN32
     /* Prefix information (NDP option) */
-    /* disabled for windows for now, until get_dns6_addr is implemented */
-    struct ndpopt *opt3 = mtod(t, struct ndpopt *);
-    opt3->ndpopt_type = NDPOPT_RDNSS;
-    opt3->ndpopt_len = NDPOPT_RDNSS_LEN / 8;
-    opt3->ndpopt_rdnss.reserved = 0;
-    opt3->ndpopt_rdnss.lifetime = htonl(2 * NDP_MaxRtrAdvInterval);
-    opt3->ndpopt_rdnss.addr = slirp->vnameserver_addr6;
-    t->m_data += NDPOPT_RDNSS_LEN;
-#endif
+    if (get_dns6_addr(&addr, &scope_id) >= 0) {
+        /* Host system does have an IPv6 DNS server, announce our proxy.  */
+        struct ndpopt *opt3 = mtod(t, struct ndpopt *);
+        opt3->ndpopt_type = NDPOPT_RDNSS;
+        opt3->ndpopt_len = NDPOPT_RDNSS_LEN / 8;
+        opt3->ndpopt_rdnss.reserved = 0;
+        opt3->ndpopt_rdnss.lifetime = htonl(2 * NDP_MaxRtrAdvInterval);
+        opt3->ndpopt_rdnss.addr = slirp->vnameserver_addr6;
+        t->m_data += NDPOPT_RDNSS_LEN;
+        pl_size += NDPOPT_RDNSS_LEN;
+    }
+
+    rip->ip_pl = htons(pl_size);
+    t->m_data -= sizeof(struct ip6) + pl_size;
+    t->m_len = sizeof(struct ip6) + pl_size;
 
     /* ICMPv6 Checksum */
-#ifndef _WIN32
-    t->m_data -= NDPOPT_RDNSS_LEN;
-#endif
-    t->m_data -= NDPOPT_PREFIXINFO_LEN;
-    t->m_data -= NDPOPT_LINKLAYER_LEN;
-    t->m_data -= ICMP6_NDP_RA_MINLEN;
-    t->m_data -= sizeof(struct ip6);
     ricmp->icmp6_cksum = ip6_cksum(t);
 
     ip6_output(NULL, t, 0);
diff --git a/slirp/slirp.c b/slirp/slirp.c
index 60539de7a3..5a94b06f5e 100644
--- a/slirp/slirp.c
+++ b/slirp/slirp.c
@@ -198,7 +198,7 @@ static int get_dns_addr_resolv_conf(int af, void *pdns_addr, void *cached_addr,
 #ifdef DEBUG
             else {
                 char s[INET6_ADDRSTRLEN];
-                char *res = inet_ntop(af, tmp_addr, s, sizeof(s));
+                const char *res = inet_ntop(af, tmp_addr, s, sizeof(s));
                 if (!res) {
                     res = "(string conversion error)";
                 }