3 /*-
4  * SPDX-License-Identifier: BSD-3-Clause
59  * This function returns the number of bytes required to hold an option
70 	nbytes += 2;	/* we need space for nxt-hdr and length fields */  in inet6_option_space()
75  * This function is called once per ancillary data object that will
76  * contain either Hop-by-Hop or Destination options.  It returns 0 on
77  * success or -1 on an error.
86 		return(-1);  in inet6_option_init()
88 	ch->cmsg_level = IPPROTO_IPV6;  in inet6_option_init()
89 	ch->cmsg_type = type;  in inet6_option_init()
90 	ch->cmsg_len = CMSG_LEN(0);  in inet6_option_init()
97  * This function appends a Hop-by-Hop option or a Destination option
99  * inet6_option_init().  This function returns 0 if it succeeds or -1 on
110 	int padlen, optlen, off;  in inet6_option_append()  local
111 	u_char *bp = (u_char *)cmsg + cmsg->cmsg_len;  in inet6_option_append()
116 		return(-1);  in inet6_option_append()
118 		return(-1);  in inet6_option_append()
127 		cmsg->cmsg_len += 2;  in inet6_option_append()
131 	off = bp - (u_char *)eh;  in inet6_option_append()
132 	padlen = roundup2(off % multx, multx) - (off % multx);  in inet6_option_append()
137 	cmsg->cmsg_len += padlen;  in inet6_option_append()
147 	cmsg->cmsg_len += optlen;  in inet6_option_append()
150 	off = bp - (u_char *)eh;  in inet6_option_append()
151 	padlen = ((off + 7) & ~7) - off;  in inet6_option_append()
154 	cmsg->cmsg_len += padlen;  in inet6_option_append()
157 	eh->ip6e_len = ((bp - (u_char *)eh) >> 3) - 1;  in inet6_option_append()
163  * This function appends a Hop-by-Hop option or a Destination option
165  * inet6_option_init().  This function returns a pointer to the 8-bit
168  * The difference between this function and inet6_option_append() is
170  * the ancillary data object while the current function returns a
178 	int padlen, off;  in inet6_option_alloc()  local
179 	u_int8_t *bp = (u_char *)cmsg + cmsg->cmsg_len;  in inet6_option_alloc()
196 		cmsg->cmsg_len += 2;  in inet6_option_alloc()
200 	off = bp - (u_char *)eh;  in inet6_option_alloc()
201 	padlen = roundup2(off % multx, multx) - (off % multx);  in inet6_option_alloc()
206 	cmsg->cmsg_len += padlen;  in inet6_option_alloc()
212 	cmsg->cmsg_len += datalen;  in inet6_option_alloc()
215 	off = bp - (u_char *)eh;  in inet6_option_alloc()
216 	padlen = ((off + 7) & ~7) - off;  in inet6_option_alloc()
219 	cmsg->cmsg_len += padlen;  in inet6_option_alloc()
222 	eh->ip6e_len = ((bp - (u_char *)eh) >> 3) - 1;  in inet6_option_alloc()
228  * This function processes the next Hop-by-Hop option or Destination
230  * processed, the return value of the function is 0 and *tptrp points to
231  * the 8-bit option type field (which is followed by the 8-bit option
233  * to be processed, the return value is -1 and *tptrp is NULL.  If an
234  * error occurs, the return value is -1 and *tptrp is not NULL.
244 	if (cmsg->cmsg_level != IPPROTO_IPV6 ||  in inet6_option_next()
245 	    (!is_ipv6_hopopts(cmsg->cmsg_type) &&  in inet6_option_next()
246 	     !is_ipv6_dstopts(cmsg->cmsg_type)))  in inet6_option_next()
247 		return(-1);  in inet6_option_next()
250 	if (cmsg->cmsg_len < CMSG_SPACE(sizeof(struct ip6_ext)))  in inet6_option_next()
251 		return(-1);  in inet6_option_next()
253 	hdrlen = (ip6e->ip6e_len + 1) << 3;  in inet6_option_next()
254 	if (cmsg->cmsg_len < CMSG_SPACE(hdrlen))  in inet6_option_next()
255 		return(-1);  in inet6_option_next()
267 			return(-1);  in inet6_option_next()
273 		return(-1);  in inet6_option_next()
280 		return(-1);  in inet6_option_next()
286  * This function is similar to the inet6_option_next() function,
287  * except this function lets the caller specify the option type to be
300 	if (cmsg->cmsg_level != IPPROTO_IPV6 ||  in inet6_option_find()
301 	    (!is_ipv6_hopopts(cmsg->cmsg_type) &&  in inet6_option_find()
302 	     !is_ipv6_dstopts(cmsg->cmsg_type)))  in inet6_option_find()
303 		return(-1);  in inet6_option_find()
306 	if (cmsg->cmsg_len < CMSG_SPACE(sizeof(struct ip6_ext)))  in inet6_option_find()
307 		return(-1);  in inet6_option_find()
309 	hdrlen = (ip6e->ip6e_len + 1) << 3;  in inet6_option_find()
310 	if (cmsg->cmsg_len < CMSG_SPACE(hdrlen))  in inet6_option_find()
311 		return(-1);	  in inet6_option_find()
323 			return(-1);  in inet6_option_find()
333 			return(-1);  in inet6_option_find()
338 	return(-1);  in inet6_option_find()
376 		 p[1] = len - 2;   in inet6_insert_padopt()
377 		 memset(&p[2], 0, len - 2);  in inet6_insert_padopt()
394 			return(-1);  in inet6_opt_init()
395 		ext->ip6e_len = (extlen >> 3) - 1;  in inet6_opt_init()
412 		return(-1);  in inet6_opt_append()
419 		return(-1);  in inet6_opt_append()
426 		return(-1);  in inet6_opt_append()
428 		return(-1);  in inet6_opt_append()
433 		padlen = align - (currentlen % align);  in inet6_opt_append()
439 		return(-1);  in inet6_opt_append()
452 			*optp++ = padlen - 2;  in inet6_opt_append()
453 			memset(optp, 0, padlen - 2);  in inet6_opt_append()
454 			optp += (padlen - 2);  in inet6_opt_append()
469 	int updatelen = offset > 0 ? (1 + ((offset - 1) | 7)) : 0;  in inet6_opt_finish()
473 		int padlen = updatelen - offset;  in inet6_opt_finish()
476 			return(-1);  in inet6_opt_finish()
483 			*padp++ = (padlen - 2);  in inet6_opt_finish()
484 			memset(padp, 0, padlen - 2);  in inet6_opt_finish()
508 		return(-1);  in inet6_opt_next()
512 	 * If this is the first time this function called for this options  in inet6_opt_next()
537 			*lenp = optlen - 2;  in inet6_opt_next()
539 			return(optp + optlen - (u_int8_t *)extbuf);  in inet6_opt_next()
545 	return(-1);  in inet6_opt_next()
557 		return(-1);  in inet6_opt_find()
561 	 * If this is the first time this function called for this options  in inet6_opt_find()
577 			*lenp = optlen - 2;  in inet6_opt_find()
579 			return(optp + optlen - (u_int8_t *)extbuf);  in inet6_opt_find()
587 	return(-1);  in inet6_opt_find()