slirp: Adding IPv6, ICMPv6 Echo and NDP autoconfiguration

This patch adds the functions needed to handle IPv6 packets. ICMPv6 and
NDP headers are implemented.

Slirp is now able to send NDP Router or Neighbor Advertisement when it
receives Router or Neighbor Solicitation. Using a 64bit-sized IPv6
prefix, the guest is now able to perform stateless autoconfiguration
(SLAAC) and to compute its IPv6 address.

This patch adds an ndp_table, mainly inspired by arp_table, to keep an
NDP cache and manage network address resolution.
Slirp regularly sends NDP Neighbor Advertisement, as recommended by the
RFC, to make the guest refresh its route.

This also adds ip6_cksum() to compute ICMPv6 checksums using IPv6
pseudo-header.

Some #define ETH_* are moved upper in slirp.h to make them accessible to
other slirp/*.h

Signed-off-by: Guillaume Subiron <maethor@subiron.org>
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>

1 files changed, 67 insertions, 0 deletions

diff --git a/slirp/ip6_input.c b/slirp/ip6_input.c
new file mode 100644
index 0000000000..add9e6a73a
--- /dev/null
+++ b/slirp/ip6_input.c
@@ -0,0 +1,67 @@
+/*
+ * Copyright (c) 2013
+ * Guillaume Subiron, Yann Bordenave, Serigne Modou Wagne.
+ */
+
+#include "qemu/osdep.h"
+#include "slirp.h"
+#include "ip6_icmp.h"
+
+/*
+ * IP initialization: fill in IP protocol switch table.
+ * All protocols not implemented in kernel go to raw IP protocol handler.
+ */
+void ip6_init(Slirp *slirp)
+{
+    icmp6_init(slirp);
+}
+
+void ip6_cleanup(Slirp *slirp)
+{
+    icmp6_cleanup(slirp);
+}
+
+void ip6_input(struct mbuf *m)
+{
+    struct ip6 *ip6;
+
+    DEBUG_CALL("ip6_input");
+    DEBUG_ARG("m = %lx", (long)m);
+    DEBUG_ARG("m_len = %d", m->m_len);
+
+    if (m->m_len < sizeof(struct ip6)) {
+        goto bad;
+    }
+
+    ip6 = mtod(m, struct ip6 *);
+
+    if (ip6->ip_v != IP6VERSION) {
+        goto bad;
+    }
+
+    /* check ip_ttl for a correct ICMP reply */
+    if (ip6->ip_hl == 0) {
+        /*icmp_error(m, ICMP_TIMXCEED,ICMP_TIMXCEED_INTRANS, 0,"ttl");*/
+        goto bad;
+    }
+
+    /*
+     * Switch out to protocol's input routine.
+     */
+    switch (ip6->ip_nh) {
+    case IPPROTO_TCP:
+        /*tcp_input(m, hlen, (struct socket *)NULL);*/
+        break;
+    case IPPROTO_UDP:
+        /*udp_input(m, hlen);*/
+        break;
+    case IPPROTO_ICMPV6:
+        icmp6_input(m);
+        break;
+    default:
+        m_free(m);
+    }
+    return;
+bad:
+    m_free(m);
+}