+ /* copy mbuf header and IPv6 + Node Information base headers */
+ bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr));
+ nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1);
+ bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo));
+
+ /* qtype dependent procedure */
+ switch (qtype) {
+ case NI_QTYPE_NOOP:
+ nni6->ni_code = ICMP6_NI_SUCCESS;
+ nni6->ni_flags = 0;
+ break;
+ case NI_QTYPE_SUPTYPES:
+ {
+ u_int32_t v;
+ nni6->ni_code = ICMP6_NI_SUCCESS;
+ nni6->ni_flags = htons(0x0000); /* raw bitmap */
+ /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */
+ v = (u_int32_t)htonl(0x0000000f);
+ bcopy(&v, nni6 + 1, sizeof(u_int32_t));
+ break;
+ }
+ case NI_QTYPE_FQDN:
+ nni6->ni_code = ICMP6_NI_SUCCESS;
+ fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) +
+ sizeof(struct ip6_hdr) +
+ sizeof(struct icmp6_nodeinfo));
+ nni6->ni_flags = 0; /* XXX: meaningless TTL */
+ fqdn->ni_fqdn_ttl = 0; /* ditto. */
+ /*
+ * XXX do we really have FQDN in variable "hostname"?
+ */
+ n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn);
+ if (n->m_next == NULL)
+ goto bad;
+ /* XXX we assume that n->m_next is not a chain */
+ if (n->m_next->m_next != NULL)
+ goto bad;
+ n->m_pkthdr.len += n->m_next->m_len;
+ break;
+ case NI_QTYPE_NODEADDR:
+ {
+ int lenlim, copied;
+
+ nni6->ni_code = ICMP6_NI_SUCCESS;
+ n->m_pkthdr.len = n->m_len =
+ sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo);
+ lenlim = M_TRAILINGSPACE(n);
+ copied = ni6_store_addrs(ni6, nni6, ifp, lenlim);
+ /* XXX: reset mbuf length */
+ n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
+ sizeof(struct icmp6_nodeinfo) + copied;
+ break;
+ }
+ default:
+ break; /* XXX impossible! */
+ }
+
+ nni6->ni_type = ICMP6_NI_REPLY;
+ m_freem(m);
+ return(n);
+
+ bad:
+ m_freem(m);
+ if (n)
+ m_freem(n);
+ return(NULL);
+}
+#undef hostnamelen
+
+/*
+ * make a mbuf with DNS-encoded string. no compression support.
+ *
+ * XXX names with less than 2 dots (like "foo" or "foo.section") will be
+ * treated as truncated name (two \0 at the end). this is a wild guess.
+ */
+static struct mbuf *
+ni6_nametodns(name, namelen, old)
+ const char *name;
+ int namelen;
+ int old; /* return pascal string if non-zero */
+{
+ struct mbuf *m;
+ char *cp, *ep;
+ const char *p, *q;
+ int i, len, nterm;
+
+ if (old)
+ len = namelen + 1;
+ else
+ len = MCLBYTES;
+
+ /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */
+ MGET(m, M_DONTWAIT, MT_DATA);
+ if (m && len > MLEN) {
+ MCLGET(m, M_DONTWAIT);
+ if ((m->m_flags & M_EXT) == 0)
+ goto fail;
+ }
+ if (!m)
+ goto fail;
+ m->m_next = NULL;
+
+ if (old) {
+ m->m_len = len;
+ *mtod(m, char *) = namelen;
+ bcopy(name, mtod(m, char *) + 1, namelen);
+ return m;
+ } else {
+ m->m_len = 0;
+ cp = mtod(m, char *);
+ ep = mtod(m, char *) + M_TRAILINGSPACE(m);
+
+ /* if not certain about my name, return empty buffer */
+ if (namelen == 0)
+ return m;
+
+ /*
+ * guess if it looks like shortened hostname, or FQDN.
+ * shortened hostname needs two trailing "\0".
+ */
+ i = 0;
+ for (p = name; p < name + namelen; p++) {
+ if (*p && *p == '.')
+ i++;
+ }
+ if (i < 2)
+ nterm = 2;
+ else
+ nterm = 1;
+
+ p = name;
+ while (cp < ep && p < name + namelen) {
+ i = 0;
+ for (q = p; q < name + namelen && *q && *q != '.'; q++)
+ i++;
+ /* result does not fit into mbuf */
+ if (cp + i + 1 >= ep)
+ goto fail;
+ /*
+ * DNS label length restriction, RFC1035 page 8.
+ * "i == 0" case is included here to avoid returning
+ * 0-length label on "foo..bar".
+ */
+ if (i <= 0 || i >= 64)
+ goto fail;
+ *cp++ = i;
+ bcopy(p, cp, i);
+ cp += i;
+ p = q;
+ if (p < name + namelen && *p == '.')
+ p++;
+ }
+ /* termination */
+ if (cp + nterm >= ep)
+ goto fail;
+ while (nterm-- > 0)
+ *cp++ = '\0';
+ m->m_len = cp - mtod(m, char *);
+ return m;
+ }
+
+ panic("should not reach here");
+ /*NOTREACHED*/
+
+ fail:
+ if (m)
+ m_freem(m);
+ return NULL;
+}
+
+/*
+ * check if two DNS-encoded string matches. takes care of truncated
+ * form (with \0\0 at the end). no compression support.
+ * XXX upper/lowercase match (see RFC2065)
+ */
+static int
+ni6_dnsmatch(a, alen, b, blen)
+ const char *a;
+ int alen;
+ const char *b;
+ int blen;
+{
+ const char *a0, *b0;
+ int l;
+
+ /* simplest case - need validation? */
+ if (alen == blen && bcmp(a, b, alen) == 0)
+ return 1;
projects / apple / xnu.git / blobdiff