slirp: Adding IPv6 UDP support

This adds the sin6 case in the fhost and lhost unions and related macros.
It adds udp6_input() and udp6_output().
It adds the IPv6 case in sorecvfrom().
Finally, udp_input() is called by ip6_input().

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, 159 insertions, 0 deletions

diff --git a/slirp/udp6.c b/slirp/udp6.c
new file mode 100644
index 0000000000..a9a36716a0
--- /dev/null
+++ b/slirp/udp6.c
@@ -0,0 +1,159 @@
+/*
+ * Copyright (c) 2013
+ * Guillaume Subiron
+ */
+
+#include "qemu/osdep.h"
+#include "qemu-common.h"
+#include "slirp.h"
+#include "qemu/osdep.h"
+#include "udp.h"
+
+void udp6_input(struct mbuf *m)
+{
+    Slirp *slirp = m->slirp;
+    struct ip6 *ip, save_ip;
+    struct udphdr *uh;
+    int iphlen = sizeof(struct ip6);
+    int len;
+    struct socket *so;
+    struct sockaddr_in6 lhost;
+
+    DEBUG_CALL("udp6_input");
+    DEBUG_ARG("m = %lx", (long)m);
+
+    if (slirp->restricted) {
+        goto bad;
+    }
+
+    ip = mtod(m, struct ip6 *);
+    m->m_len -= iphlen;
+    m->m_data += iphlen;
+    uh = mtod(m, struct udphdr *);
+    m->m_len += iphlen;
+    m->m_data -= iphlen;
+
+    if (ip6_cksum(m)) {
+        goto bad;
+    }
+
+    len = ntohs((uint16_t)uh->uh_ulen);
+
+    /*
+     * Make mbuf data length reflect UDP length.
+     * If not enough data to reflect UDP length, drop.
+     */
+    if (ntohs(ip->ip_pl) != len) {
+        if (len > ntohs(ip->ip_pl)) {
+            goto bad;
+        }
+        m_adj(m, len - ntohs(ip->ip_pl));
+        ip->ip_pl = htons(len);
+    }
+
+    /*
+     * Save a copy of the IP header in case we want restore it
+     * for sending an ICMP error message in response.
+     */
+    save_ip = *ip;
+
+    /* TODO handle DHCP/BOOTP */
+    /* TODO handle TFTP */
+
+    /* Locate pcb for datagram. */
+    lhost.sin6_family = AF_INET6;
+    lhost.sin6_addr = ip->ip_src;
+    lhost.sin6_port = uh->uh_sport;
+
+    so = solookup(&slirp->udp_last_so, &slirp->udb,
+                  (struct sockaddr_storage *) &lhost, NULL);
+
+    if (so == NULL) {
+        /* If there's no socket for this packet, create one. */
+        so = socreate(slirp);
+        if (!so) {
+            goto bad;
+        }
+        if (udp_attach(so, AF_INET6) == -1) {
+            DEBUG_MISC((dfd, " udp6_attach errno = %d-%s\n",
+                        errno, strerror(errno)));
+            sofree(so);
+            goto bad;
+        }
+
+        /* Setup fields */
+        so->so_lfamily = AF_INET6;
+        so->so_laddr6 = ip->ip_src;
+        so->so_lport6 = uh->uh_sport;
+    }
+
+    so->so_ffamily = AF_INET6;
+    so->so_faddr6 = ip->ip_dst; /* XXX */
+    so->so_fport6 = uh->uh_dport; /* XXX */
+
+    iphlen += sizeof(struct udphdr);
+    m->m_len -= iphlen;
+    m->m_data += iphlen;
+
+    /*
+     * Now we sendto() the packet.
+     */
+    if (sosendto(so, m) == -1) {
+        m->m_len += iphlen;
+        m->m_data -= iphlen;
+        *ip = save_ip;
+        DEBUG_MISC((dfd, "udp tx errno = %d-%s\n", errno, strerror(errno)));
+        /* TODO: ICMPv6 error */
+        /*icmp_error(m, ICMP_UNREACH,ICMP_UNREACH_NET, 0,strerror(errno));*/
+        goto bad;
+    }
+
+    m_free(so->so_m);   /* used for ICMP if error on sorecvfrom */
+
+    /* restore the orig mbuf packet */
+    m->m_len += iphlen;
+    m->m_data -= iphlen;
+    *ip = save_ip;
+    so->so_m = m;
+
+    return;
+bad:
+    m_free(m);
+}
+
+int udp6_output(struct socket *so, struct mbuf *m,
+        struct sockaddr_in6 *saddr, struct sockaddr_in6 *daddr)
+{
+    struct ip6 *ip;
+    struct udphdr *uh;
+
+    DEBUG_CALL("udp6_output");
+    DEBUG_ARG("so = %lx", (long)so);
+    DEBUG_ARG("m = %lx", (long)m);
+
+    /* adjust for header */
+    m->m_data -= sizeof(struct udphdr);
+    m->m_len += sizeof(struct udphdr);
+    uh = mtod(m, struct udphdr *);
+    m->m_data -= sizeof(struct ip6);
+    m->m_len += sizeof(struct ip6);
+    ip = mtod(m, struct ip6 *);
+
+    /* Build IP header */
+    ip->ip_pl = htons(m->m_len - sizeof(struct ip6));
+    ip->ip_nh = IPPROTO_UDP;
+    ip->ip_src = saddr->sin6_addr;
+    ip->ip_dst = daddr->sin6_addr;
+
+    /* Build UDP header */
+    uh->uh_sport = saddr->sin6_port;
+    uh->uh_dport = daddr->sin6_port;
+    uh->uh_ulen = ip->ip_pl;
+    uh->uh_sum = 0;
+    uh->uh_sum = ip6_cksum(m);
+    if (uh->uh_sum == 0) {
+        uh->uh_sum = 0xffff;
+    }
+
+    return ip6_output(so, m, 0);
+}