/* $NetBSD: udp6_output.c,v 1.55.6.2 2018/11/06 14:44:22 martin Exp $ */ /* $KAME: udp6_output.c,v 1.43 2001/10/15 09:19:52 itojun Exp $ */ /* * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the project nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * Copyright (c) 1982, 1986, 1989, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)udp_var.h 8.1 (Berkeley) 6/10/93 */ #include __KERNEL_RCSID(0, "$NetBSD: udp6_output.c,v 1.55.6.2 2018/11/06 14:44:22 martin Exp $"); #ifdef _KERNEL_OPT #include "opt_inet.h" #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "faith.h" #include /* * UDP protocol inplementation. * Per RFC 768, August, 1980. */ int udp6_output(struct in6pcb * const in6p, struct mbuf *m, struct sockaddr_in6 * const addr6, struct mbuf * const control, struct lwp * const l) { u_int32_t ulen = m->m_pkthdr.len; u_int32_t plen = sizeof(struct udphdr) + ulen; struct ip6_hdr *ip6; struct udphdr *udp6; struct in6_addr _laddr, *laddr, *faddr; struct in6_addr laddr_mapped; /* XXX ugly */ struct sockaddr_in6 *sin6 = NULL; struct ifnet *oifp = NULL; int scope_ambiguous = 0; u_int16_t fport; int error = 0; struct ip6_pktopts *optp = NULL; struct ip6_pktopts opt; int af = AF_INET6, hlen = sizeof(struct ip6_hdr); #ifdef INET struct ip *ip; struct udpiphdr *ui; int flags = 0; #endif struct sockaddr_in6 tmp; if (addr6) { sin6 = addr6; if (sin6->sin6_len != sizeof(*sin6)) { error = EINVAL; goto release; } if (sin6->sin6_family != AF_INET6) { error = EAFNOSUPPORT; goto release; } /* protect *sin6 from overwrites */ tmp = *sin6; sin6 = &tmp; /* * Application should provide a proper zone ID or the use of * default zone IDs should be enabled. Unfortunately, some * applications do not behave as it should, so we need a * workaround. Even if an appropriate ID is not determined, * we'll see if we can determine the outgoing interface. If we * can, determine the zone ID based on the interface below. */ if (sin6->sin6_scope_id == 0 && !ip6_use_defzone) scope_ambiguous = 1; if ((error = sa6_embedscope(sin6, ip6_use_defzone)) != 0) goto release; } if (control) { if ((error = ip6_setpktopts(control, &opt, in6p->in6p_outputopts, l->l_cred, IPPROTO_UDP)) != 0) goto release; optp = &opt; } else optp = in6p->in6p_outputopts; if (sin6) { /* * Slightly different than v4 version in that we call * in6_selectsrc and in6_pcbsetport to fill in the local * address and port rather than in_pcbconnect. in_pcbconnect * sets in6p_faddr which causes EISCONN below to be hit on * subsequent sendto. */ if (sin6->sin6_port == 0) { error = EADDRNOTAVAIL; goto release; } if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) { /* how about ::ffff:0.0.0.0 case? */ error = EISCONN; goto release; } faddr = &sin6->sin6_addr; fport = sin6->sin6_port; /* allow 0 port */ if (IN6_IS_ADDR_V4MAPPED(faddr)) { if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY)) { /* * I believe we should explicitly discard the * packet when mapped addresses are disabled, * rather than send the packet as an IPv6 one. * If we chose the latter approach, the packet * might be sent out on the wire based on the * default route, the situation which we'd * probably want to avoid. * (20010421 jinmei@kame.net) */ error = EINVAL; goto release; } if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && !IN6_IS_ADDR_V4MAPPED(&in6p->in6p_laddr)) { /* * when remote addr is an IPv4-mapped address, * local addr should not be an IPv6 address, * since you cannot determine how to map IPv6 * source address to IPv4. */ error = EINVAL; goto release; } af = AF_INET; } if (!IN6_IS_ADDR_V4MAPPED(faddr)) { struct psref psref; int bound = curlwp_bind(); error = in6_selectsrc(sin6, optp, in6p->in6p_moptions, &in6p->in6p_route, &in6p->in6p_laddr, &oifp, &psref, &_laddr); if (error) laddr = NULL; else laddr = &_laddr; if (oifp && scope_ambiguous && (error = in6_setscope(&sin6->sin6_addr, oifp, NULL))) { if_put(oifp, &psref); curlwp_bindx(bound); goto release; } if_put(oifp, &psref); curlwp_bindx(bound); } else { /* * XXX: freebsd[34] does not have in_selectsrc, but * we can omit the whole part because freebsd4 calls * udp_output() directly in this case, and thus we'll * never see this path. */ if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) { struct sockaddr_in sin_dst; struct in_addr ina; struct in_ifaddr *ia4; struct psref _psref; int bound; memcpy(&ina, &faddr->s6_addr[12], sizeof(ina)); sockaddr_in_init(&sin_dst, &ina, 0); bound = curlwp_bind(); ia4 = in_selectsrc(&sin_dst, &in6p->in6p_route, in6p->in6p_socket->so_options, NULL, &error, &_psref); if (ia4 == NULL) { curlwp_bindx(bound); if (error == 0) error = EADDRNOTAVAIL; goto release; } memset(&laddr_mapped, 0, sizeof(laddr_mapped)); laddr_mapped.s6_addr16[5] = 0xffff; /* ugly */ memcpy(&laddr_mapped.s6_addr[12], &IA_SIN(ia4)->sin_addr, sizeof(IA_SIN(ia4)->sin_addr)); ia4_release(ia4, &_psref); curlwp_bindx(bound); laddr = &laddr_mapped; } else { laddr = &in6p->in6p_laddr; /* XXX */ } } if (laddr == NULL) { if (error == 0) error = EADDRNOTAVAIL; goto release; } if (in6p->in6p_lport == 0) { /* * Craft a sockaddr_in6 for the local endpoint. Use the * "any" as a base, set the address, and recover the * scope. */ struct sockaddr_in6 lsin6 = *((const struct sockaddr_in6 *)in6p->in6p_socket->so_proto->pr_domain->dom_sa_any); lsin6.sin6_addr = *laddr; error = sa6_recoverscope(&lsin6); if (error) goto release; error = in6_pcbsetport(&lsin6, in6p, l); if (error) { in6p->in6p_laddr = in6addr_any; goto release; } } } else { if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) { error = ENOTCONN; goto release; } if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_faddr)) { if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY)) { /* * XXX: this case would happen when the * application sets the V6ONLY flag after * connecting the foreign address. * Such applications should be fixed, * so we bark here. */ log(LOG_INFO, "udp6_output: IPV6_V6ONLY " "option was set for a connected socket\n"); error = EINVAL; goto release; } else af = AF_INET; } laddr = &in6p->in6p_laddr; faddr = &in6p->in6p_faddr; fport = in6p->in6p_fport; } if (af == AF_INET) hlen = sizeof(struct ip); /* * Calculate data length and get a mbuf * for UDP and IP6 headers. */ M_PREPEND(m, hlen + sizeof(struct udphdr), M_DONTWAIT); if (m == 0) { error = ENOBUFS; goto release; } /* * Stuff checksum and output datagram. */ udp6 = (struct udphdr *)(mtod(m, char *) + hlen); udp6->uh_sport = in6p->in6p_lport; /* lport is always set in the PCB */ udp6->uh_dport = fport; if (plen <= 0xffff) udp6->uh_ulen = htons((u_int16_t)plen); else udp6->uh_ulen = 0; udp6->uh_sum = 0; switch (af) { case AF_INET6: ip6 = mtod(m, struct ip6_hdr *); ip6->ip6_flow = in6p->in6p_flowinfo & IPV6_FLOWINFO_MASK; ip6->ip6_vfc &= ~IPV6_VERSION_MASK; ip6->ip6_vfc |= IPV6_VERSION; #if 0 /* ip6_plen will be filled in ip6_output. */ ip6->ip6_plen = htons((u_int16_t)plen); #endif ip6->ip6_nxt = IPPROTO_UDP; ip6->ip6_hlim = in6_selecthlim_rt(in6p); ip6->ip6_src = *laddr; ip6->ip6_dst = *faddr; udp6->uh_sum = in6_cksum_phdr(laddr, faddr, htonl(plen), htonl(IPPROTO_UDP)); m->m_pkthdr.csum_flags = M_CSUM_UDPv6; m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); UDP6_STATINC(UDP6_STAT_OPACKETS); error = ip6_output(m, optp, &in6p->in6p_route, 0, in6p->in6p_moptions, in6p, NULL); break; case AF_INET: #ifdef INET /* can't transmit jumbogram over IPv4 */ if (plen > 0xffff) { error = EMSGSIZE; goto release; } ip = mtod(m, struct ip *); ui = (struct udpiphdr *)ip; memset(ui->ui_x1, 0, sizeof(ui->ui_x1)); ui->ui_pr = IPPROTO_UDP; ui->ui_len = htons(plen); memcpy(&ui->ui_src, &laddr->s6_addr[12], sizeof(ui->ui_src)); ui->ui_ulen = ui->ui_len; flags = (in6p->in6p_socket->so_options & (SO_DONTROUTE | SO_BROADCAST)); memcpy(&ui->ui_dst, &faddr->s6_addr[12], sizeof(ui->ui_dst)); udp6->uh_sum = in_cksum(m, hlen + plen); if (udp6->uh_sum == 0) udp6->uh_sum = 0xffff; ip->ip_len = htons(hlen + plen); ip->ip_ttl = in6_selecthlim(in6p, NULL); /* XXX */ ip->ip_tos = 0; /* XXX */ UDP_STATINC(UDP_STAT_OPACKETS); error = ip_output(m, NULL, &in6p->in6p_route, flags /* XXX */, in6p->in6p_v4moptions, NULL); break; #else error = EAFNOSUPPORT; goto release; #endif } goto releaseopt; release: m_freem(m); releaseopt: if (control) { if (optp == &opt) ip6_clearpktopts(&opt, -1); m_freem(control); } return (error); }