diff options
Diffstat (limited to 'src/VBox/Devices/Network/slirp/udp.c')
| -rw-r--r-- | src/VBox/Devices/Network/slirp/udp.c | 685 |
1 files changed, 685 insertions, 0 deletions
diff --git a/src/VBox/Devices/Network/slirp/udp.c b/src/VBox/Devices/Network/slirp/udp.c new file mode 100644 index 00000000..ebd9c20e --- /dev/null +++ b/src/VBox/Devices/Network/slirp/udp.c @@ -0,0 +1,685 @@ +/* $Id: udp.c $ */ +/** @file + * NAT - UDP protocol. + */ + +/* + * Copyright (C) 2006-2023 Oracle and/or its affiliates. + * + * This file is part of VirtualBox base platform packages, as + * available from https://www.virtualbox.org. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, in version 3 of the + * License. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <https://www.gnu.org/licenses>. + * + * SPDX-License-Identifier: GPL-3.0-only + */ + +/* + * This code is based on: + * + * Copyright (c) 1982, 1986, 1988, 1990, 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_usrreq.c 8.4 (Berkeley) 1/21/94 + * udp_usrreq.c,v 1.4 1994/10/02 17:48:45 phk Exp + */ + +/* + * Changes and additions relating to SLiRP + * Copyright (c) 1995 Danny Gasparovski. + * + * Please read the file COPYRIGHT for the + * terms and conditions of the copyright. + */ + +#include <slirp.h> +#include "ip_icmp.h" + + +/* + * UDP protocol implementation. + * Per RFC 768, August, 1980. + */ +#define udpcksum 1 + +void +udp_init(PNATState pData) +{ + udp_last_so = &udb; + udb.so_next = udb.so_prev = &udb; +} + +/* m->m_data points at ip packet header + * m->m_len length ip packet + * ip->ip_len length data (IPDU) + */ +void +udp_input(PNATState pData, register struct mbuf *m, int iphlen) +{ + register struct ip *ip; + register struct udphdr *uh; + int len; + struct ip save_ip; + struct socket *so; + int ret; + int ttl, tos; + + LogFlowFunc(("ENTER: m = %p, iphlen = %d\n", m, iphlen)); + ip = mtod(m, struct ip *); + Log2(("%RTnaipv4 iphlen = %d\n", ip->ip_dst, iphlen)); + + udpstat.udps_ipackets++; + + /* + * Strip IP options, if any; should skip this, + * make available to user, and use on returned packets, + * but we don't yet have a way to check the checksum + * with options still present. + */ + if (iphlen > sizeof(struct ip)) + { + ip_stripoptions(m, (struct mbuf *)0); + iphlen = sizeof(struct ip); + } + + /* + * Get IP and UDP header together in first mbuf. + */ + ip = mtod(m, struct ip *); + uh = (struct udphdr *)((caddr_t)ip + iphlen); + + /* + * Make mbuf data length reflect UDP length. + * If not enough data to reflect UDP length, drop. + */ + len = RT_N2H_U16((u_int16_t)uh->uh_ulen); + Assert(ip->ip_len + iphlen == (ssize_t)m_length(m, NULL)); + + if (ip->ip_len != len) + { + if (len > ip->ip_len) + { + udpstat.udps_badlen++; + Log3(("NAT: IP(id: %hd) has bad size\n", ip->ip_id)); + goto bad_free_mbuf; + } + m_adj(m, len - ip->ip_len); + ip->ip_len = 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; + save_ip.ip_len+= iphlen; /* tcp_input subtracts this */ + + /* + * Checksum extended UDP header and data. + */ + if (udpcksum && uh->uh_sum) + { + memset(((struct ipovly *)ip)->ih_x1, 0, 9); + ((struct ipovly *)ip)->ih_len = uh->uh_ulen; +#if 0 + /* keep uh_sum for ICMP reply */ + uh->uh_sum = cksum(m, len + sizeof (struct ip)); + if (uh->uh_sum) + { + +#endif + if (cksum(m, len + iphlen)) + { + udpstat.udps_badsum++; + Log3(("NAT: IP(id: %hd) has bad (udp) cksum\n", ip->ip_id)); + goto bad_free_mbuf; + } + } +#if 0 + } +#endif + + /* + * handle DHCP/BOOTP + */ + if (uh->uh_dport == RT_H2N_U16_C(BOOTP_SERVER)) + { + bootp_input(pData, m); + goto done_free_mbuf; + } + + LogFunc(("uh src: %RTnaipv4:%d, dst: %RTnaipv4:%d\n", + ip->ip_src.s_addr, RT_N2H_U16(uh->uh_sport), + ip->ip_dst.s_addr, RT_N2H_U16(uh->uh_dport))); + + /* + * handle DNS host resolver without creating a socket + */ + if ( pData->fUseHostResolver + && uh->uh_dport == RT_H2N_U16_C(53) + && CTL_CHECK(ip->ip_dst.s_addr, CTL_DNS)) + { + struct sockaddr_in dst, src; + + src.sin_addr.s_addr = ip->ip_dst.s_addr; + src.sin_port = uh->uh_dport; + dst.sin_addr.s_addr = ip->ip_src.s_addr; + dst.sin_port = uh->uh_sport; + + m_adj(m, sizeof(struct udpiphdr)); + + m = hostresolver(pData, m, ip->ip_src.s_addr, uh->uh_sport); + if (m == NULL) + goto done_free_mbuf; + + slirpMbufTagService(pData, m, CTL_DNS); + + udp_output2(pData, NULL, m, &src, &dst, IPTOS_LOWDELAY); + LogFlowFuncLeave(); + return; + } + + /* + * handle TFTP + */ + if ( uh->uh_dport == RT_H2N_U16_C(TFTP_SERVER) + && CTL_CHECK(ip->ip_dst.s_addr, CTL_TFTP)) + { + if (pData->pvTftpSessions) + slirpTftpInput(pData, m); + goto done_free_mbuf; + } + + /* + * XXX: DNS proxy currently relies on the fact that each socket + * only serves one request. + */ + if ( pData->fUseDnsProxy + && CTL_CHECK(ip->ip_dst.s_addr, CTL_DNS) + && (uh->uh_dport == RT_H2N_U16_C(53))) + { + so = NULL; + goto new_socket; + } + + /* + * Drop UDP packets destind for CTL_ALIAS (i.e. the hosts loopback interface) + * if it is disabled. + */ + if ( CTL_CHECK(ip->ip_dst.s_addr, CTL_ALIAS) + && !pData->fLocalhostReachable) + goto done_free_mbuf; + + /* + * Locate pcb for datagram. + */ + so = udp_last_so; + if ( so->so_lport != uh->uh_sport + || so->so_laddr.s_addr != ip->ip_src.s_addr) + { + struct socket *tmp; + + for (tmp = udb.so_next; tmp != &udb; tmp = tmp->so_next) + { + if ( tmp->so_lport == uh->uh_sport + && tmp->so_laddr.s_addr == ip->ip_src.s_addr) + { + so = tmp; + break; + } + } + if (tmp == &udb) + so = NULL; + else + { + udpstat.udpps_pcbcachemiss++; + udp_last_so = so; + } + } + + new_socket: + if (so == NULL) + { + /* + * If there's no socket for this packet, + * create one + */ + if ((so = socreate()) == NULL) + { + Log2(("NAT: IP(id: %hd) failed to create socket\n", ip->ip_id)); + goto bad_free_mbuf; + } + + /* + * Setup fields + */ + so->so_laddr = ip->ip_src; + so->so_lport = uh->uh_sport; + so->so_iptos = ip->ip_tos; + + if (udp_attach(pData, so) <= 0) + { + Log2(("NAT: IP(id: %hd) udp_attach errno = %d (%s)\n", + ip->ip_id, errno, strerror(errno))); + sofree(pData, so); + goto bad_free_mbuf; + } + + /* udp_last_so = so; */ + /* + * XXXXX Here, check if it's in udpexec_list, + * and if it is, do the fork_exec() etc. + */ + } + + so->so_faddr = ip->ip_dst; /* XXX */ + so->so_fport = uh->uh_dport; /* XXX */ + Assert(so->so_type == IPPROTO_UDP); + + /* + * DNS proxy + */ + if ( pData->fUseDnsProxy + && CTL_CHECK(ip->ip_dst.s_addr, CTL_DNS) + && (uh->uh_dport == RT_H2N_U16_C(53))) + { + dnsproxy_query(pData, so, m, iphlen); + goto done_free_mbuf; + } + + iphlen += sizeof(struct udphdr); + m->m_len -= iphlen; + m->m_data += iphlen; + + ttl = ip->ip_ttl = save_ip.ip_ttl; + if (ttl != so->so_sottl) { + ret = setsockopt(so->s, IPPROTO_IP, IP_TTL, + (char *)&ttl, sizeof(ttl)); + if (RT_LIKELY(ret == 0)) + so->so_sottl = ttl; + } + + tos = save_ip.ip_tos; + if (tos != so->so_sotos) { + ret = setsockopt(so->s, IPPROTO_IP, IP_TOS, + (char *)&tos, sizeof(tos)); + if (RT_LIKELY(ret == 0)) + so->so_sotos = tos; + } + + { + /* + * Different OSes have different socket options for DF. We + * can't use IP_HDRINCL here as it's only valid for SOCK_RAW. + */ +# define USE_DF_OPTION(_Optname) \ + const int dfopt = _Optname +#if defined(IP_MTU_DISCOVER) + USE_DF_OPTION(IP_MTU_DISCOVER); +#elif defined(IP_DONTFRAG) /* Solaris 11+, FreeBSD */ + USE_DF_OPTION(IP_DONTFRAG); +#elif defined(IP_DONTFRAGMENT) /* Windows */ + USE_DF_OPTION(IP_DONTFRAGMENT); +#else + USE_DF_OPTION(0); +#endif + if (dfopt) { + int df = (save_ip.ip_off & IP_DF) != 0; +#if defined(IP_MTU_DISCOVER) + df = df ? IP_PMTUDISC_DO : IP_PMTUDISC_DONT; +#endif + if (df != so->so_sodf) { + ret = setsockopt(so->s, IPPROTO_IP, dfopt, + (char *)&df, sizeof(df)); + if (RT_LIKELY(ret == 0)) + so->so_sodf = df; + } + } + } + + if ( sosendto(pData, so, m) == -1 + && ( !soIgnorableErrorCode(errno) + && errno != ENOTCONN)) + { + m->m_len += iphlen; + m->m_data -= iphlen; + *ip = save_ip; + Log2(("NAT: UDP tx errno = %d (%s) on sent to %RTnaipv4\n", + errno, strerror(errno), ip->ip_dst)); + icmp_error(pData, m, ICMP_UNREACH, ICMP_UNREACH_NET, 0, strerror(errno)); + so->so_m = NULL; + LogFlowFuncLeave(); + return; + } + + if (so->so_m) + m_freem(pData, 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; /* ICMP backup */ + LogFlowFuncLeave(); + return; + +bad_free_mbuf: + Log2(("NAT: UDP(id: %hd) datagram to %RTnaipv4 with size(%d) claimed as bad\n", + ip->ip_id, &ip->ip_dst, ip->ip_len)); + +done_free_mbuf: + /* some services like bootp(built-in), dns(buildt-in) and dhcp don't need sockets + * and create new m'buffers to send them to guest, so we'll free their incomming + * buffers here. + */ + if (m != NULL) + m_freem(pData, m); + LogFlowFuncLeave(); + return; +} + +/** + * Output a UDP packet. + * + * @note This function will finally free m! + */ +int udp_output2(PNATState pData, struct socket *so, struct mbuf *m, + struct sockaddr_in *saddr, struct sockaddr_in *daddr, + int iptos) +{ + register struct udpiphdr *ui; + int error; + int mlen = 0; + + LogFlowFunc(("ENTER: so = %R[natsock], m = %p, saddr = %RTnaipv4, daddr = %RTnaipv4\n", + so, m, saddr->sin_addr.s_addr, daddr->sin_addr.s_addr)); + + /* in case of built-in service so might be NULL */ + if (so) Assert(so->so_type == IPPROTO_UDP); + + /* + * Adjust for header + */ + m->m_data -= sizeof(struct udpiphdr); + m->m_len += sizeof(struct udpiphdr); + mlen = m_length(m, NULL); + + /* + * Fill in mbuf with extended UDP header + * and addresses and length put into network format. + */ + ui = mtod(m, struct udpiphdr *); + memset(ui->ui_x1, 0, 9); + ui->ui_pr = IPPROTO_UDP; + ui->ui_len = RT_H2N_U16((uint16_t)(mlen - sizeof(struct ip))); + /* XXXXX Check for from-one-location sockets, or from-any-location sockets */ + ui->ui_src = saddr->sin_addr; + ui->ui_dst = daddr->sin_addr; + ui->ui_sport = saddr->sin_port; + ui->ui_dport = daddr->sin_port; + ui->ui_ulen = ui->ui_len; + + /* + * Stuff checksum and output datagram. + */ + ui->ui_sum = 0; + if (udpcksum) + { + if ((ui->ui_sum = cksum(m, /* sizeof (struct udpiphdr) + */ mlen)) == 0) + ui->ui_sum = 0xffff; + } + ((struct ip *)ui)->ip_len = mlen; + ((struct ip *)ui)->ip_ttl = ip_defttl; + ((struct ip *)ui)->ip_tos = iptos; + + udpstat.udps_opackets++; + + error = ip_output(pData, so, m); + + return error; +} + +/** + * @note This function will free m! + */ +int udp_output(PNATState pData, struct socket *so, struct mbuf *m, + struct sockaddr_in *addr) +{ + struct sockaddr_in saddr, daddr; + + Assert(so->so_type == IPPROTO_UDP); + LogFlowFunc(("ENTER: so = %R[natsock], m = %p, saddr = %RTnaipv4\n", so, m, addr->sin_addr.s_addr)); + + if (so->so_laddr.s_addr == INADDR_ANY) + { + if (pData->guest_addr_guess.s_addr != INADDR_ANY) + { + LogRel2(("NAT: port-forward: using %RTnaipv4 for %R[natsock]\n", + pData->guest_addr_guess.s_addr, so)); + so->so_laddr = pData->guest_addr_guess; + } + else + { + LogRel2(("NAT: port-forward: guest address unknown for %R[natsock]\n", so)); + m_freem(pData, m); + return 0; + } + } + + saddr = *addr; + if ((so->so_faddr.s_addr & RT_H2N_U32(pData->netmask)) == pData->special_addr.s_addr) + { + saddr.sin_addr.s_addr = so->so_faddr.s_addr; + if (slirpIsWideCasting(pData, so->so_faddr.s_addr)) + { + /** + * We haven't got real firewall but have got its submodule libalias. + */ + m->m_flags |= M_SKIP_FIREWALL; + /** + * udp/137 port is Name Service in NetBIOS protocol. for some reasons Windows guest rejects + * accept data from non-aliased server. + */ + if ( (so->so_fport == so->so_lport) + && (so->so_fport == RT_H2N_U16(137))) + saddr.sin_addr.s_addr = alias_addr.s_addr; + else + saddr.sin_addr.s_addr = addr->sin_addr.s_addr; + so->so_faddr.s_addr = addr->sin_addr.s_addr; + } + } + + /* Any UDP packet to the loopback address must be translated to be from + * the forwarding address, i.e. 10.0.2.2. */ + if ( (saddr.sin_addr.s_addr & RT_H2N_U32_C(IN_CLASSA_NET)) + == RT_H2N_U32_C(INADDR_LOOPBACK & IN_CLASSA_NET)) + saddr.sin_addr.s_addr = alias_addr.s_addr; + + daddr.sin_addr = so->so_laddr; + daddr.sin_port = so->so_lport; + + return udp_output2(pData, so, m, &saddr, &daddr, so->so_iptos); +} + +int +udp_attach(PNATState pData, struct socket *so) +{ + struct sockaddr sa_addr; + socklen_t socklen = sizeof(struct sockaddr); + int status; + int opt = 1; + + AssertReturn(so->so_type == 0, -1); + so->so_type = IPPROTO_UDP; + + so->s = socket(AF_INET, SOCK_DGRAM, 0); + if (so->s == -1) + goto error; + fd_nonblock(so->s); + + so->so_sottl = 0; + so->so_sotos = 0; + so->so_sodf = -1; + + status = sobind(pData, so); + if (status != 0) + return status; + + /* success, insert in queue */ + so->so_expire = curtime + SO_EXPIRE; + + /* enable broadcast for later use */ + setsockopt(so->s, SOL_SOCKET, SO_BROADCAST, (const char *)&opt, sizeof(opt)); + + status = getsockname(so->s, &sa_addr, &socklen); + if (status == 0) + { + Assert(sa_addr.sa_family == AF_INET); + so->so_hlport = ((struct sockaddr_in *)&sa_addr)->sin_port; + so->so_hladdr.s_addr = ((struct sockaddr_in *)&sa_addr)->sin_addr.s_addr; + } + + SOCKET_LOCK_CREATE(so); + QSOCKET_LOCK(udb); + insque(pData, so, &udb); + NSOCK_INC(); + QSOCKET_UNLOCK(udb); + return so->s; +error: + Log2(("NAT: can't create datagram socket\n")); + return -1; +} + +void +udp_detach(PNATState pData, struct socket *so) +{ + if (so != &pData->icmp_socket) + { + Assert(so->so_type == IPPROTO_UDP); + QSOCKET_LOCK(udb); + SOCKET_LOCK(so); + QSOCKET_UNLOCK(udb); + closesocket(so->s); + sofree(pData, so); + SOCKET_UNLOCK(so); + } +} + +struct socket * +udp_listen(PNATState pData, u_int32_t bind_addr, u_int port, u_int32_t laddr, u_int lport, int flags) +{ + struct sockaddr_in addr; + struct socket *so; + socklen_t addrlen = sizeof(struct sockaddr_in); + int opt = 1; + LogFlowFunc(("ENTER: bind_addr:%RTnaipv4, port:%d, laddr:%RTnaipv4, lport:%d, flags:%x\n", + bind_addr, RT_N2H_U16(port), laddr, RT_N2H_U16(lport), flags)); + + if ((so = socreate()) == NULL) + { + LogFlowFunc(("LEAVE: NULL\n")); + return NULL; + } + + so->s = socket(AF_INET, SOCK_DGRAM, 0); + if (so->s == -1) + { + LogRel(("NAT: can't create datagram socket\n")); + RTMemFree(so); + LogFlowFunc(("LEAVE: NULL\n")); + return NULL; + } + so->so_expire = curtime + SO_EXPIRE; + so->so_type = IPPROTO_UDP; + fd_nonblock(so->s); + so->so_sottl = 0; + so->so_sotos = 0; + so->so_sodf = -1; + SOCKET_LOCK_CREATE(so); + QSOCKET_LOCK(udb); + insque(pData, so, &udb); + NSOCK_INC(); + QSOCKET_UNLOCK(udb); + + memset(&addr, 0, sizeof(addr)); +#ifdef RT_OS_DARWIN + addr.sin_len = sizeof(addr); +#endif + addr.sin_family = AF_INET; + addr.sin_addr.s_addr = bind_addr; + addr.sin_port = port; + + if (bind(so->s,(struct sockaddr *)&addr, addrlen) < 0) + { + LogRel(("NAT: udp bind to %RTnaipv4:%d failed, error %d\n", + addr.sin_addr, RT_N2H_U16(port), errno)); + udp_detach(pData, so); + LogFlowFunc(("LEAVE: NULL\n")); + return NULL; + } + setsockopt(so->s, SOL_SOCKET, SO_REUSEADDR,(char *)&opt, sizeof(int)); +/* setsockopt(so->s, SOL_SOCKET, SO_OOBINLINE,(char *)&opt, sizeof(int)); */ + + getsockname(so->s,(struct sockaddr *)&addr,&addrlen); + so->so_hladdr = addr.sin_addr; + so->so_hlport = addr.sin_port; + + /* XXX: wtf are we setting so_faddr/so_fport here? */ + so->so_fport = addr.sin_port; +#if 0 + /* The original check was completely broken, as the commented out + * if statement was always true (INADDR_ANY=0). */ + /** @todo vvl - alias_addr should be set (if required) + * later by liabalias module. + */ + if (addr.sin_addr.s_addr == 0 || addr.sin_addr.s_addr == loopback_addr.s_addr) + so->so_faddr = alias_addr; + else +#endif + so->so_faddr = addr.sin_addr; + + so->so_lport = lport; + so->so_laddr.s_addr = laddr; + if (flags != SS_FACCEPTONCE) + so->so_expire = 0; + + so->so_state = SS_ISFCONNECTED; + + LogFlowFunc(("LEAVE: %R[natsock]\n", so)); + return so; +} |