From f215e02bf85f68d3a6106c2a1f4f7f063f819064 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:17:27 +0200 Subject: Adding upstream version 7.0.14-dfsg. Signed-off-by: Daniel Baumann --- src/VBox/NetworkServices/NAT/fwudp.c | 555 +++++++++++++++++++++++++++++++++++ 1 file changed, 555 insertions(+) create mode 100644 src/VBox/NetworkServices/NAT/fwudp.c (limited to 'src/VBox/NetworkServices/NAT/fwudp.c') diff --git a/src/VBox/NetworkServices/NAT/fwudp.c b/src/VBox/NetworkServices/NAT/fwudp.c new file mode 100644 index 00000000..7c0b69f9 --- /dev/null +++ b/src/VBox/NetworkServices/NAT/fwudp.c @@ -0,0 +1,555 @@ +/* $Id: fwudp.c $ */ +/** @file + * NAT Network - UDP port-forwarding. + */ + +/* + * Copyright (C) 2013-2023 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 . + * + * SPDX-License-Identifier: GPL-3.0-only + */ + +#define LOG_GROUP LOG_GROUP_NAT_SERVICE + +#include "winutils.h" +#include "proxy.h" +#include "proxy_pollmgr.h" +#include "portfwd.h" +#include "pxremap.h" + +#ifndef RT_OS_WINDOWS +#include +#include +#include +#include +#include + +#include /* BSD'ism */ +#else +#include +#include +#include "winpoll.h" +#endif + +#include "lwip/opt.h" +#include "lwip/memp.h" /* XXX: for bulk delete of pcbs */ + +#include "lwip/sys.h" +#include "lwip/tcpip.h" +#include "lwip/udp.h" + +struct fwudp_dgram { + struct pbuf *p; + ipX_addr_t src_addr; + u16_t src_port; +}; + +/** + * UDP port-forwarding. + * + * Unlike pxudp that uses 1:1 mapping between pcb and socket, for + * port-forwarded UDP the setup is bit more elaborated. + * + * For fwtcp things are simple since incoming TCP connection get a new + * socket that we just hand off to pxtcp. Thus fwtcp only handles + * connection initiation. + * + * For fwudp all proxied UDP conversations share the same socket, so + * single fwudp multiplexes to several UDP pcbs. + * + * XXX: TODO: Currently pcbs point back directly to fwudp. It might + * make sense to introduce a per-pcb structure that points to fwudp + * and carries additional information, like pre-mapped peer address. + */ +struct fwudp { + /** + * Our poll manager handler. + */ + struct pollmgr_handler pmhdl; + + /** + * Forwarding specification. + */ + struct fwspec fwspec; + + /** + * XXX: lwip-format copy of destination + */ + ipX_addr_t dst_addr; + u16_t dst_port; + + /** + * Listening socket. + */ + SOCKET sock; + + /** + * Ring-buffer for inbound datagrams. + */ + struct { + struct fwudp_dgram *buf; + size_t bufsize; + volatile size_t vacant; + volatile size_t unsent; + } inbuf; + + struct tcpip_msg msg_send; + struct tcpip_msg msg_delete; + + struct fwudp *next; +}; + + +struct fwudp *fwudp_create(struct fwspec *); + +/* poll manager callback for fwudp socket */ +static int fwudp_pmgr_pump(struct pollmgr_handler *, SOCKET, int); + +/* lwip thread callbacks called via proxy_lwip_post() */ +static void fwudp_pcb_send(void *); +static void fwudp_pcb_delete(void *); + +static void fwudp_pcb_recv(void *, struct udp_pcb *, struct pbuf *, ip_addr_t *, u16_t); +static void fwudp_pcb_forward_outbound(struct fwudp *, struct udp_pcb *, struct pbuf *); + + +/** + * Linked list of active fwtcp forwarders. + */ +struct fwudp *fwudp_list = NULL; + + +void +fwudp_init(void) +{ + return; +} + + +void +fwudp_add(struct fwspec *fwspec) +{ + struct fwudp *fwudp; + + fwudp = fwudp_create(fwspec); + if (fwudp == NULL) { + DPRINTF0(("%s: failed to add rule for UDP ...\n", __func__)); + return; + } + + DPRINTF0(("%s\n", __func__)); + /* fwudp_create has put fwudp on the linked list */ +} + + +void +fwudp_del(struct fwspec *fwspec) +{ + struct fwudp *fwudp; + struct fwudp **pprev; + + for (pprev = &fwudp_list; (fwudp = *pprev) != NULL; pprev = &fwudp->next) { + if (fwspec_equal(&fwudp->fwspec, fwspec)) { + *pprev = fwudp->next; + fwudp->next = NULL; + break; + } + } + + if (fwudp == NULL) { + DPRINTF0(("%s: not found\n", __func__)); + return; + } + + DPRINTF0(("%s\n", __func__)); + + pollmgr_del_slot(fwudp->pmhdl.slot); + fwudp->pmhdl.slot = -1; + + /* let pending msg_send be processed before we delete fwudp */ + proxy_lwip_post(&fwudp->msg_delete); +} + + +struct fwudp * +fwudp_create(struct fwspec *fwspec) +{ + struct fwudp *fwudp; + SOCKET sock; + int status; + + sock = proxy_bound_socket(fwspec->sdom, fwspec->stype, &fwspec->src.sa); + if (sock == INVALID_SOCKET) { + return NULL; + } + + fwudp = (struct fwudp *)malloc(sizeof(*fwudp)); + if (fwudp == NULL) { + closesocket(sock); + return NULL; + } + + fwudp->pmhdl.callback = fwudp_pmgr_pump; + fwudp->pmhdl.data = (void *)fwudp; + fwudp->pmhdl.slot = -1; + + fwudp->sock = sock; + fwudp->fwspec = *fwspec; /* struct copy */ + + /* XXX */ + if (fwspec->sdom == PF_INET) { + struct sockaddr_in *dst4 = &fwspec->dst.sin; + memcpy(&fwudp->dst_addr.ip4, &dst4->sin_addr, sizeof(ip_addr_t)); + fwudp->dst_port = htons(dst4->sin_port); + } + else { /* PF_INET6 */ + struct sockaddr_in6 *dst6 = &fwspec->dst.sin6; + memcpy(&fwudp->dst_addr.ip6, &dst6->sin6_addr, sizeof(ip6_addr_t)); + fwudp->dst_port = htons(dst6->sin6_port); + } + + fwudp->inbuf.bufsize = 256; /* elements */ + fwudp->inbuf.buf + = (struct fwudp_dgram *)calloc(fwudp->inbuf.bufsize, + sizeof(struct fwudp_dgram)); + if (fwudp->inbuf.buf == NULL) { + closesocket(sock); + free(fwudp); + return (NULL); + } + fwudp->inbuf.vacant = 0; + fwudp->inbuf.unsent = 0; + +#define CALLBACK_MSG(MSG, FUNC) \ + do { \ + fwudp->MSG.type = TCPIP_MSG_CALLBACK_STATIC; \ + fwudp->MSG.sem = NULL; \ + fwudp->MSG.msg.cb.function = FUNC; \ + fwudp->MSG.msg.cb.ctx = (void *)fwudp; \ + } while (0) + + CALLBACK_MSG(msg_send, fwudp_pcb_send); + CALLBACK_MSG(msg_delete, fwudp_pcb_delete); + +#undef CALLBACK_MSG + + status = pollmgr_add(&fwudp->pmhdl, fwudp->sock, POLLIN); + if (status < 0) { + closesocket(sock); + free(fwudp->inbuf.buf); + free(fwudp); + return NULL; + } + + fwudp->next = fwudp_list; + fwudp_list = fwudp; + + return fwudp; +} + + +/** + * Poll manager callaback for fwudp::sock + */ +int +fwudp_pmgr_pump(struct pollmgr_handler *handler, SOCKET fd, int revents) +{ + struct fwudp *fwudp; + struct sockaddr_storage ss; + socklen_t sslen = sizeof(ss); + size_t beg, lim; + struct fwudp_dgram *dgram; + struct pbuf *p; + ssize_t nread; + int status; + err_t error; + + fwudp = (struct fwudp *)handler->data; + + LWIP_ASSERT1(fwudp != NULL); + LWIP_ASSERT1(fd == fwudp->sock); + LWIP_ASSERT1(revents == POLLIN); + LWIP_UNUSED_ARG(fd); + LWIP_UNUSED_ARG(revents); + +#ifdef RT_OS_WINDOWS + nread = recvfrom(fwudp->sock, (char *)pollmgr_udpbuf, sizeof(pollmgr_udpbuf), 0, + (struct sockaddr *)&ss, &sslen); +#else + nread = recvfrom(fwudp->sock, pollmgr_udpbuf, sizeof(pollmgr_udpbuf), 0, + (struct sockaddr *)&ss, &sslen); +#endif + if (nread < 0) { + DPRINTF(("%s: %R[sockerr]\n", __func__, SOCKERRNO())); + return POLLIN; + } + + /* Check that ring buffer is not full */ + lim = fwudp->inbuf.unsent; + if (lim == 0) { + lim = fwudp->inbuf.bufsize - 1; /* guard slot at the end */ + } + else { + --lim; + } + + beg = fwudp->inbuf.vacant; + if (beg == lim) { /* no vacant slot */ + return POLLIN; + } + + + dgram = &fwudp->inbuf.buf[beg]; + + + status = fwany_ipX_addr_set_src(&dgram->src_addr, (struct sockaddr *)&ss); + if (status == PXREMAP_FAILED) { + return POLLIN; + } + + if (ss.ss_family == AF_INET) { + const struct sockaddr_in *peer4 = (const struct sockaddr_in *)&ss; + dgram->src_port = htons(peer4->sin_port); + } + else { /* PF_INET6 */ + const struct sockaddr_in6 *peer6 = (const struct sockaddr_in6 *)&ss; + dgram->src_port = htons(peer6->sin6_port); + } + + p = pbuf_alloc(PBUF_RAW, nread, PBUF_RAM); + if (p == NULL) { + DPRINTF(("%s: pbuf_alloc(%d) failed\n", __func__, (int)nread)); + return POLLIN; + } + + error = pbuf_take(p, pollmgr_udpbuf, nread); + if (error != ERR_OK) { + DPRINTF(("%s: pbuf_take(%d) failed\n", __func__, (int)nread)); + pbuf_free(p); + return POLLIN; + } + + dgram->p = p; + + ++beg; + if (beg == fwudp->inbuf.bufsize) { + beg = 0; + } + fwudp->inbuf.vacant = beg; + + proxy_lwip_post(&fwudp->msg_send); + + return POLLIN; +} + + +/** + * Lwip thread callback invoked via fwudp::msg_send + */ +void +fwudp_pcb_send(void *arg) +{ + struct fwudp *fwudp = (struct fwudp *)arg; + struct fwudp_dgram dgram; + struct udp_pcb *pcb; + struct udp_pcb **pprev; + int isv6; + size_t idx; + + idx = fwudp->inbuf.unsent; + + if (idx == fwudp->inbuf.vacant) { + /* empty buffer - shouldn't happen! */ + DPRINTF(("%s: ring buffer empty!\n", __func__)); + return; + } + + dgram = fwudp->inbuf.buf[idx]; /* struct copy */ +#if 1 /* valgrind hint */ + fwudp->inbuf.buf[idx].p = NULL; +#endif + if (++idx == fwudp->inbuf.bufsize) { + idx = 0; + } + fwudp->inbuf.unsent = idx; + + /* XXX: this is *STUPID* */ + isv6 = (fwudp->fwspec.sdom == PF_INET6); + pprev = &udp_proxy_pcbs; + for (pcb = udp_proxy_pcbs; pcb != NULL; pcb = pcb->next) { + if (PCB_ISIPV6(pcb) == isv6 + && pcb->remote_port == fwudp->dst_port + && ipX_addr_cmp(isv6, &fwudp->dst_addr, &pcb->remote_ip) + && pcb->local_port == dgram.src_port + && ipX_addr_cmp(isv6, &dgram.src_addr, &pcb->local_ip)) + { + break; + } + else { + pprev = &pcb->next; + } + } + + if (pcb != NULL) { + *pprev = pcb->next; + pcb->next = udp_proxy_pcbs; + udp_proxy_pcbs = pcb; + + /* + * XXX: check that its ours and not accidentally created by + * outbound traffic. + * + * ???: Otherwise? Expire it and set pcb = NULL; to create a + * new one below? + */ + } + + if (pcb == NULL) { + pcb = udp_new(); + if (pcb == NULL) { + goto out; + } + + ip_set_v6(pcb, isv6); + + /* equivalent of udp_bind */ + ipX_addr_set(isv6, &pcb->local_ip, &dgram.src_addr); + pcb->local_port = dgram.src_port; + + /* equivalent to udp_connect */ + ipX_addr_set(isv6, &pcb->remote_ip, &fwudp->dst_addr); + pcb->remote_port = fwudp->dst_port; + pcb->flags |= UDP_FLAGS_CONNECTED; + + udp_recv(pcb, fwudp_pcb_recv, fwudp); + + pcb->next = udp_proxy_pcbs; + udp_proxy_pcbs = pcb; + udp_proxy_timer_needed(); + } + + udp_send(pcb, dgram.p); + + out: + pbuf_free(dgram.p); +} + + +/** + * udp_recv() callback. + */ +void +fwudp_pcb_recv(void *arg, struct udp_pcb *pcb, struct pbuf *p, + ip_addr_t *addr, u16_t port) +{ + struct fwudp *fwudp = (struct fwudp *)arg; + + LWIP_UNUSED_ARG(addr); + LWIP_UNUSED_ARG(port); + + LWIP_ASSERT1(fwudp != NULL); + + if (p == NULL) { + DPRINTF(("%s: pcb %p (fwudp %p); sock %d: expired\n", + __func__, (void *)pcb, (void *)fwudp, fwudp->sock)); + /* NB: fwudp is "global" and not deleted */ + /* XXX: TODO: delete local reference when we will keep one */ + udp_remove(pcb); + return; + } + else { + fwudp_pcb_forward_outbound(fwudp, pcb, p); + } +} + + +/* + * XXX: This is pxudp_pcb_forward_outbound modulo: + * - s/pxudp/fwudp/g + * - addr/port (unused in either) dropped + * - destination is specified since host socket is not connected + */ +static void +fwudp_pcb_forward_outbound(struct fwudp *fwudp, struct udp_pcb *pcb, + struct pbuf *p) +{ + union { + struct sockaddr_in sin; + struct sockaddr_in6 sin6; + } peer; + socklen_t namelen; + + memset(&peer, 0, sizeof(peer)); /* XXX: shut up valgrind */ + + if (fwudp->fwspec.sdom == PF_INET) { + peer.sin.sin_family = AF_INET; +#if HAVE_SA_LEN + peer.sin.sin_len = +#endif + namelen = sizeof(peer.sin); + pxremap_outbound_ip4((ip_addr_t *)&peer.sin.sin_addr, &pcb->local_ip.ip4); + peer.sin.sin_port = htons(pcb->local_port); + } + else { + peer.sin6.sin6_family = AF_INET6; +#if HAVE_SA_LEN + peer.sin6.sin6_len = +#endif + namelen = sizeof(peer.sin6); + + pxremap_outbound_ip6((ip6_addr_t *)&peer.sin6.sin6_addr, &pcb->local_ip.ip6); + peer.sin6.sin6_port = htons(pcb->local_port); + } + + proxy_sendto(fwudp->sock, p, &peer, namelen); + pbuf_free(p); +} + + +/** + * Lwip thread callback invoked via fwudp::msg_delete + */ +static void +fwudp_pcb_delete(void *arg) +{ + struct fwudp *fwudp = (struct fwudp *)arg; + struct udp_pcb *pcb; + struct udp_pcb **pprev; + + LWIP_ASSERT1(fwudp->inbuf.unsent == fwudp->inbuf.vacant); + + pprev = &udp_proxy_pcbs; + pcb = udp_proxy_pcbs; + while (pcb != NULL) { + if (pcb->recv_arg != fwudp) { + pprev = &pcb->next; + pcb = pcb->next; + } + else { + struct udp_pcb *dead = pcb; + pcb = pcb->next; + *pprev = pcb; + memp_free(MEMP_UDP_PCB, dead); + } + } + + closesocket(fwudp->sock); + free(fwudp->inbuf.buf); + free(fwudp); +} -- cgit v1.2.3