--- src/lib/libc/net/ip6opt.c	2006/07/08 01:04:28	1.5
+++ src/lib/libc/net/ip6opt.c	2007/05/29 10:58:11	1.6
@@ -366,3 +366,225 @@ inet6_insert_padopt(u_char *p, int len)
 		 return;
 	}
 }
+
+/*
+ * The following functions are defined in RFC3542, which is a successor
+ * of RFC2292.
+ */
+
+int
+inet6_opt_init(void *extbuf, socklen_t extlen)
+{
+	struct ip6_ext *ext = (struct ip6_ext *)extbuf;
+
+	if (extlen < 0 || (extlen % 8))
+		return (-1);
+
+	if (ext) {
+		if (extlen == 0)
+			return (-1);
+		ext->ip6e_len = (extlen >> 3) - 1;
+	}
+
+	return (2);		/* sizeof the next and the length fields */
+}
+
+int
+inet6_opt_append(void *extbuf, socklen_t extlen, int offset, u_int8_t type,
+		 socklen_t len, u_int8_t align, void **databufp)
+{
+	int currentlen = offset, padlen = 0;
+
+	/*
+	 * The option type must have a value from 2 to 255, inclusive.
+	 * (0 and 1 are reserved for the Pad1 and PadN options, respectively.)
+	 */
+#if 0 /* always false */
+	if (type < 2 || type > 255)
+#else
+	if (type < 2)
+#endif
+		return (-1);
+
+	/*
+	 * The option data length must have a value between 0 and 255,
+	 * inclusive, and is the length of the option data that follows.
+	 */
+	if (len < 0 || len > 255)
+		return (-1);
+
+	/*
+	 * The align parameter must have a value of 1, 2, 4, or 8.
+	 * The align value can not exceed the value of len.
+	 */
+	if (align != 1 && align != 2 && align != 4 && align != 8)
+		return (-1);
+	if (align > len)
+		return (-1);
+
+	/* Calculate the padding length. */
+	currentlen += 2 + len;	/* 2 means "type + len" */
+	if (currentlen % align)
+		padlen = align - (currentlen % align);
+
+	/* The option must fit in the extension header buffer. */
+	currentlen += padlen;
+	if (extlen &&		/* XXX: right? */
+	    currentlen > extlen)
+		return (-1);
+
+	if (extbuf) {
+		u_int8_t *optp = (u_int8_t *)extbuf + offset;
+
+		if (padlen == 1) {
+			/* insert a Pad1 option */
+			*optp = IP6OPT_PAD1;
+			optp++;
+		} else if (padlen > 0) {
+			/* insert a PadN option for alignment */
+			*optp++ = IP6OPT_PADN;
+			*optp++ = padlen - 2;
+			memset(optp, 0, padlen - 2);
+			optp += (padlen - 2);
+		}
+
+		*optp++ = type;
+		*optp++ = len;
+
+		*databufp = optp;
+	}
+
+	return (currentlen);
+}
+
+int
+inet6_opt_finish(void *extbuf, socklen_t extlen, int offset)
+{
+	int updatelen = offset > 0 ? (1 + ((offset - 1) | 7)) : 0;;
+
+	if (extbuf) {
+		u_int8_t *padp;
+		int padlen = updatelen - offset;
+
+		if (updatelen > extlen)
+			return (-1);
+
+		padp = (u_int8_t *)extbuf + offset;
+		if (padlen == 1)
+			*padp = IP6OPT_PAD1;
+		else if (padlen > 0) {
+			*padp++ = IP6OPT_PADN;
+			*padp++ = (padlen - 2);
+			memset(padp, 0, padlen - 2);
+		}
+	}
+
+	return (updatelen);
+}
+
+int
+inet6_opt_set_val(void *databuf, int offset, void *val, socklen_t vallen)
+{
+
+	memcpy((u_int8_t *)databuf + offset, val, vallen);
+	return (offset + vallen);
+}
+
+int
+inet6_opt_next(void *extbuf, socklen_t extlen, int offset, u_int8_t *typep,
+	       socklen_t *lenp, void **databufp)
+{
+	u_int8_t *optp, *lim;
+	int optlen;
+
+	/* Validate extlen. XXX: is the variable really necessary?? */
+	if (extlen == 0 || (extlen % 8))
+		return (-1);
+	lim = (u_int8_t *)extbuf + extlen;
+
+	/*
+	 * If this is the first time this function called for this options
+	 * header, simply return the 1st option.
+	 * Otherwise, search the option list for the next option.
+	 */
+	if (offset == 0)
+		optp = (u_int8_t *)((struct ip6_hbh *)extbuf + 1);
+	else
+		optp = (u_int8_t *)extbuf + offset;
+
+	/* Find the next option skipping any padding options. */
+	while (optp < lim) {
+		switch(*optp) {
+		case IP6OPT_PAD1:
+			optp++;
+			break;
+		case IP6OPT_PADN:
+			if ((optlen = ip6optlen(optp, lim)) == 0)
+				goto optend;
+			optp += optlen;
+			break;
+		default:	/* found */
+			if ((optlen = ip6optlen(optp, lim)) == 0)
+				goto optend;
+			*typep = *optp;
+			*lenp = optlen - 2;
+			*databufp = optp + 2;
+			return (optp + optlen - (u_int8_t *)extbuf);
+		}
+	}
+
+  optend:
+	*databufp = NULL; /* for safety */
+	return (-1);
+}
+
+int
+inet6_opt_find(void *extbuf, socklen_t extlen, int offset, u_int8_t type,
+	       socklen_t *lenp, void **databufp)
+{
+	u_int8_t *optp, *lim;
+	int optlen;
+
+	/* Validate extlen. XXX: is the variable really necessary?? */
+	if (extlen == 0 || (extlen % 8))
+		return (-1);
+	lim = (u_int8_t *)extbuf + extlen;
+
+	/*
+	 * If this is the first time this function called for this options
+	 * header, simply return the 1st option.
+	 * Otherwise, search the option list for the next option.
+	 */
+	if (offset == 0)
+		optp = (u_int8_t *)((struct ip6_hbh *)extbuf + 1);
+	else
+		optp = (u_int8_t *)extbuf + offset;
+
+	/* Find the specified option */
+	while (optp < lim) {
+		if ((optlen = ip6optlen(optp, lim)) == 0)
+			goto optend;
+
+		if (*optp == type) { /* found */
+			*lenp = optlen - 2;
+			*databufp = optp + 2;
+			return (optp + optlen - (u_int8_t *)extbuf);
+		}
+
+		optp += optlen;
+	}
+
+  optend:
+	*databufp = NULL; /* for safety */
+	return (-1);
+}
+
+int
+inet6_opt_get_val(void *databuf, int offset, void *val, socklen_t vallen)
+{
+
+	/* we can't assume alignment here */
+	memcpy(val, (u_int8_t *)databuf + offset, vallen);
+
+	return (offset + vallen);
+}