diff options
Diffstat (limited to 'slirp/src/slirp.c')
| -rw-r--r-- | slirp/src/slirp.c | 1117 |
1 files changed, 1117 insertions, 0 deletions
diff --git a/slirp/src/slirp.c b/slirp/src/slirp.c new file mode 100644 index 0000000000..18af670a0a --- /dev/null +++ b/slirp/src/slirp.c @@ -0,0 +1,1117 @@ +/* + * libslirp glue + * + * Copyright (c) 2004-2008 Fabrice Bellard + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ +#include "slirp.h" + + +#ifndef _WIN32 +#include <net/if.h> +#endif + +int slirp_debug; + +/* Define to 1 if you want KEEPALIVE timers */ +bool slirp_do_keepalive; + +/* host loopback address */ +struct in_addr loopback_addr; +/* host loopback network mask */ +unsigned long loopback_mask; + +/* emulated hosts use the MAC addr 52:55:IP:IP:IP:IP */ +static const uint8_t special_ethaddr[ETH_ALEN] = { + 0x52, 0x55, 0x00, 0x00, 0x00, 0x00 +}; + +unsigned curtime; + +static struct in_addr dns_addr; +#ifndef _WIN32 +static struct in6_addr dns6_addr; +#endif +static unsigned dns_addr_time; +#ifndef _WIN32 +static unsigned dns6_addr_time; +#endif + +#define TIMEOUT_FAST 2 /* milliseconds */ +#define TIMEOUT_SLOW 499 /* milliseconds */ +/* for the aging of certain requests like DNS */ +#define TIMEOUT_DEFAULT 1000 /* milliseconds */ + +#ifdef _WIN32 + +int get_dns_addr(struct in_addr *pdns_addr) +{ + FIXED_INFO *FixedInfo=NULL; + ULONG BufLen; + DWORD ret; + IP_ADDR_STRING *pIPAddr; + struct in_addr tmp_addr; + + if (dns_addr.s_addr != 0 && (curtime - dns_addr_time) < TIMEOUT_DEFAULT) { + *pdns_addr = dns_addr; + return 0; + } + + FixedInfo = (FIXED_INFO *)GlobalAlloc(GPTR, sizeof(FIXED_INFO)); + BufLen = sizeof(FIXED_INFO); + + if (ERROR_BUFFER_OVERFLOW == GetNetworkParams(FixedInfo, &BufLen)) { + if (FixedInfo) { + GlobalFree(FixedInfo); + FixedInfo = NULL; + } + FixedInfo = GlobalAlloc(GPTR, BufLen); + } + + if ((ret = GetNetworkParams(FixedInfo, &BufLen)) != ERROR_SUCCESS) { + printf("GetNetworkParams failed. ret = %08x\n", (unsigned)ret ); + if (FixedInfo) { + GlobalFree(FixedInfo); + FixedInfo = NULL; + } + return -1; + } + + pIPAddr = &(FixedInfo->DnsServerList); + inet_aton(pIPAddr->IpAddress.String, &tmp_addr); + *pdns_addr = tmp_addr; + dns_addr = tmp_addr; + dns_addr_time = curtime; + if (FixedInfo) { + GlobalFree(FixedInfo); + FixedInfo = NULL; + } + return 0; +} + +int get_dns6_addr(struct in6_addr *pdns6_addr, uint32_t *scope_id) +{ + return -1; +} + +static void winsock_cleanup(void) +{ + WSACleanup(); +} + +#else + +static int get_dns_addr_cached(void *pdns_addr, void *cached_addr, + socklen_t addrlen, + struct stat *cached_stat, unsigned *cached_time) +{ + struct stat old_stat; + if (curtime - *cached_time < TIMEOUT_DEFAULT) { + memcpy(pdns_addr, cached_addr, addrlen); + return 0; + } + old_stat = *cached_stat; + if (stat("/etc/resolv.conf", cached_stat) != 0) { + return -1; + } + if (cached_stat->st_dev == old_stat.st_dev + && cached_stat->st_ino == old_stat.st_ino + && cached_stat->st_size == old_stat.st_size + && cached_stat->st_mtime == old_stat.st_mtime) { + memcpy(pdns_addr, cached_addr, addrlen); + return 0; + } + return 1; +} + +static int get_dns_addr_resolv_conf(int af, void *pdns_addr, void *cached_addr, + socklen_t addrlen, uint32_t *scope_id, + unsigned *cached_time) +{ + char buff[512]; + char buff2[257]; + FILE *f; + int found = 0; + void *tmp_addr = alloca(addrlen); + unsigned if_index; + + f = fopen("/etc/resolv.conf", "r"); + if (!f) + return -1; + + DEBUG_MISC("IP address of your DNS(s):"); + while (fgets(buff, 512, f) != NULL) { + if (sscanf(buff, "nameserver%*[ \t]%256s", buff2) == 1) { + char *c = strchr(buff2, '%'); + if (c) { + if_index = if_nametoindex(c + 1); + *c = '\0'; + } else { + if_index = 0; + } + + if (!inet_pton(af, buff2, tmp_addr)) { + continue; + } + /* If it's the first one, set it to dns_addr */ + if (!found) { + memcpy(pdns_addr, tmp_addr, addrlen); + memcpy(cached_addr, tmp_addr, addrlen); + if (scope_id) { + *scope_id = if_index; + } + *cached_time = curtime; + } + + if (++found > 3) { + DEBUG_MISC(" (more)"); + break; + } else if (slirp_debug & DBG_MISC) { + char s[INET6_ADDRSTRLEN]; + const char *res = inet_ntop(af, tmp_addr, s, sizeof(s)); + if (!res) { + res = " (string conversion error)"; + } + DEBUG_MISC(" %s", res); + } + } + } + fclose(f); + if (!found) + return -1; + return 0; +} + +int get_dns_addr(struct in_addr *pdns_addr) +{ + static struct stat dns_addr_stat; + + if (dns_addr.s_addr != 0) { + int ret; + ret = get_dns_addr_cached(pdns_addr, &dns_addr, sizeof(dns_addr), + &dns_addr_stat, &dns_addr_time); + if (ret <= 0) { + return ret; + } + } + return get_dns_addr_resolv_conf(AF_INET, pdns_addr, &dns_addr, + sizeof(dns_addr), NULL, &dns_addr_time); +} + +int get_dns6_addr(struct in6_addr *pdns6_addr, uint32_t *scope_id) +{ + static struct stat dns6_addr_stat; + + if (!in6_zero(&dns6_addr)) { + int ret; + ret = get_dns_addr_cached(pdns6_addr, &dns6_addr, sizeof(dns6_addr), + &dns6_addr_stat, &dns6_addr_time); + if (ret <= 0) { + return ret; + } + } + return get_dns_addr_resolv_conf(AF_INET6, pdns6_addr, &dns6_addr, + sizeof(dns6_addr), + scope_id, &dns6_addr_time); +} + +#endif + +static void slirp_init_once(void) +{ + static int initialized; + const char *debug; +#ifdef _WIN32 + WSADATA Data; +#endif + + if (initialized) { + return; + } + initialized = 1; + +#ifdef _WIN32 + WSAStartup(MAKEWORD(2,0), &Data); + atexit(winsock_cleanup); +#endif + + loopback_addr.s_addr = htonl(INADDR_LOOPBACK); + loopback_mask = htonl(IN_CLASSA_NET); + + debug = g_getenv("SLIRP_DEBUG"); + if (debug) { + const GDebugKey keys[] = { + { "call", DBG_CALL }, + { "misc", DBG_MISC }, + { "error", DBG_ERROR }, + { "tftp", DBG_TFTP }, + }; + slirp_debug = g_parse_debug_string(debug, keys, G_N_ELEMENTS(keys)); + } + + +} + +Slirp *slirp_init(int restricted, bool in_enabled, struct in_addr vnetwork, + struct in_addr vnetmask, struct in_addr vhost, + bool in6_enabled, + struct in6_addr vprefix_addr6, uint8_t vprefix_len, + struct in6_addr vhost6, const char *vhostname, + const char *tftp_server_name, + const char *tftp_path, const char *bootfile, + struct in_addr vdhcp_start, struct in_addr vnameserver, + struct in6_addr vnameserver6, const char **vdnssearch, + const char *vdomainname, + const SlirpCb *callbacks, + void *opaque) +{ + Slirp *slirp = g_malloc0(sizeof(Slirp)); + + slirp_init_once(); + + slirp->opaque = opaque; + slirp->cb = callbacks; + slirp->grand = g_rand_new(); + slirp->restricted = restricted; + + slirp->in_enabled = in_enabled; + slirp->in6_enabled = in6_enabled; + + if_init(slirp); + ip_init(slirp); + ip6_init(slirp); + + /* Initialise mbufs *after* setting the MTU */ + m_init(slirp); + + slirp->vnetwork_addr = vnetwork; + slirp->vnetwork_mask = vnetmask; + slirp->vhost_addr = vhost; + slirp->vprefix_addr6 = vprefix_addr6; + slirp->vprefix_len = vprefix_len; + slirp->vhost_addr6 = vhost6; + if (vhostname) { + slirp_pstrcpy(slirp->client_hostname, sizeof(slirp->client_hostname), + vhostname); + } + slirp->tftp_prefix = g_strdup(tftp_path); + slirp->bootp_filename = g_strdup(bootfile); + slirp->vdomainname = g_strdup(vdomainname); + slirp->vdhcp_startaddr = vdhcp_start; + slirp->vnameserver_addr = vnameserver; + slirp->vnameserver_addr6 = vnameserver6; + slirp->tftp_server_name = g_strdup(tftp_server_name); + + if (vdnssearch) { + translate_dnssearch(slirp, vdnssearch); + } + + return slirp; +} + +void slirp_cleanup(Slirp *slirp) +{ + struct gfwd_list *e, *next; + + for (e = slirp->guestfwd_list; e; e = next) { + next = e->ex_next; + g_free(e->ex_exec); + g_free(e); + } + + ip_cleanup(slirp); + ip6_cleanup(slirp); + m_cleanup(slirp); + + g_rand_free(slirp->grand); + + g_free(slirp->vdnssearch); + g_free(slirp->tftp_prefix); + g_free(slirp->bootp_filename); + g_free(slirp->vdomainname); + g_free(slirp); +} + +#define CONN_CANFSEND(so) (((so)->so_state & (SS_FCANTSENDMORE|SS_ISFCONNECTED)) == SS_ISFCONNECTED) +#define CONN_CANFRCV(so) (((so)->so_state & (SS_FCANTRCVMORE|SS_ISFCONNECTED)) == SS_ISFCONNECTED) + +static void slirp_update_timeout(Slirp *slirp, uint32_t *timeout) +{ + uint32_t t; + + if (*timeout <= TIMEOUT_FAST) { + return; + } + + t = MIN(1000, *timeout); + + /* If we have tcp timeout with slirp, then we will fill @timeout with + * more precise value. + */ + if (slirp->time_fasttimo) { + *timeout = TIMEOUT_FAST; + return; + } + if (slirp->do_slowtimo) { + t = MIN(TIMEOUT_SLOW, t); + } + *timeout = t; +} + +void slirp_pollfds_fill(Slirp *slirp, uint32_t *timeout, + SlirpAddPollCb add_poll, void *opaque) +{ + struct socket *so, *so_next; + + /* + * First, TCP sockets + */ + + /* + * *_slowtimo needs calling if there are IP fragments + * in the fragment queue, or there are TCP connections active + */ + slirp->do_slowtimo = ((slirp->tcb.so_next != &slirp->tcb) || + (&slirp->ipq.ip_link != slirp->ipq.ip_link.next)); + + for (so = slirp->tcb.so_next; so != &slirp->tcb; so = so_next) { + int events = 0; + + so_next = so->so_next; + + so->pollfds_idx = -1; + + /* + * See if we need a tcp_fasttimo + */ + if (slirp->time_fasttimo == 0 && + so->so_tcpcb->t_flags & TF_DELACK) { + slirp->time_fasttimo = curtime; /* Flag when want a fasttimo */ + } + + /* + * NOFDREF can include still connecting to local-host, + * newly socreated() sockets etc. Don't want to select these. + */ + if (so->so_state & SS_NOFDREF || so->s == -1) { + continue; + } + + /* + * Set for reading sockets which are accepting + */ + if (so->so_state & SS_FACCEPTCONN) { + so->pollfds_idx = add_poll(so->s, + SLIRP_POLL_IN | SLIRP_POLL_HUP | SLIRP_POLL_ERR, opaque); + continue; + } + + /* + * Set for writing sockets which are connecting + */ + if (so->so_state & SS_ISFCONNECTING) { + so->pollfds_idx = add_poll(so->s, + SLIRP_POLL_OUT | SLIRP_POLL_ERR, opaque); + continue; + } + + /* + * Set for writing if we are connected, can send more, and + * we have something to send + */ + if (CONN_CANFSEND(so) && so->so_rcv.sb_cc) { + events |= SLIRP_POLL_OUT | SLIRP_POLL_ERR; + } + + /* + * Set for reading (and urgent data) if we are connected, can + * receive more, and we have room for it XXX /2 ? + */ + if (CONN_CANFRCV(so) && + (so->so_snd.sb_cc < (so->so_snd.sb_datalen/2))) { + events |= SLIRP_POLL_IN | SLIRP_POLL_HUP | + SLIRP_POLL_ERR | SLIRP_POLL_PRI; + } + + if (events) { + so->pollfds_idx = add_poll(so->s, events, opaque); + } + } + + /* + * UDP sockets + */ + for (so = slirp->udb.so_next; so != &slirp->udb; so = so_next) { + so_next = so->so_next; + + so->pollfds_idx = -1; + + /* + * See if it's timed out + */ + if (so->so_expire) { + if (so->so_expire <= curtime) { + udp_detach(so); + continue; + } else { + slirp->do_slowtimo = true; /* Let socket expire */ + } + } + + /* + * When UDP packets are received from over the + * link, they're sendto()'d straight away, so + * no need for setting for writing + * Limit the number of packets queued by this session + * to 4. Note that even though we try and limit this + * to 4 packets, the session could have more queued + * if the packets needed to be fragmented + * (XXX <= 4 ?) + */ + if ((so->so_state & SS_ISFCONNECTED) && so->so_queued <= 4) { + so->pollfds_idx = add_poll(so->s, + SLIRP_POLL_IN | SLIRP_POLL_HUP | SLIRP_POLL_ERR, opaque); + } + } + + /* + * ICMP sockets + */ + for (so = slirp->icmp.so_next; so != &slirp->icmp; so = so_next) { + so_next = so->so_next; + + so->pollfds_idx = -1; + + /* + * See if it's timed out + */ + if (so->so_expire) { + if (so->so_expire <= curtime) { + icmp_detach(so); + continue; + } else { + slirp->do_slowtimo = true; /* Let socket expire */ + } + } + + if (so->so_state & SS_ISFCONNECTED) { + so->pollfds_idx = add_poll(so->s, + SLIRP_POLL_IN | SLIRP_POLL_HUP | SLIRP_POLL_ERR, opaque); + } + } + + slirp_update_timeout(slirp, timeout); +} + +void slirp_pollfds_poll(Slirp *slirp, int select_error, + SlirpGetREventsCb get_revents, void *opaque) +{ + struct socket *so, *so_next; + int ret; + + curtime = slirp->cb->clock_get_ns(slirp->opaque) / SCALE_MS; + + /* + * See if anything has timed out + */ + if (slirp->time_fasttimo && + ((curtime - slirp->time_fasttimo) >= TIMEOUT_FAST)) { + tcp_fasttimo(slirp); + slirp->time_fasttimo = 0; + } + if (slirp->do_slowtimo && + ((curtime - slirp->last_slowtimo) >= TIMEOUT_SLOW)) { + ip_slowtimo(slirp); + tcp_slowtimo(slirp); + slirp->last_slowtimo = curtime; + } + + /* + * Check sockets + */ + if (!select_error) { + /* + * Check TCP sockets + */ + for (so = slirp->tcb.so_next; so != &slirp->tcb; + so = so_next) { + int revents; + + so_next = so->so_next; + + revents = 0; + if (so->pollfds_idx != -1) { + revents = get_revents(so->pollfds_idx, opaque); + } + + if (so->so_state & SS_NOFDREF || so->s == -1) { + continue; + } + + /* + * Check for URG data + * This will soread as well, so no need to + * test for SLIRP_POLL_IN below if this succeeds + */ + if (revents & SLIRP_POLL_PRI) { + ret = sorecvoob(so); + if (ret < 0) { + /* Socket error might have resulted in the socket being + * removed, do not try to do anything more with it. */ + continue; + } + } + /* + * Check sockets for reading + */ + else if (revents & + (SLIRP_POLL_IN | SLIRP_POLL_HUP | SLIRP_POLL_ERR)) { + /* + * Check for incoming connections + */ + if (so->so_state & SS_FACCEPTCONN) { + tcp_connect(so); + continue; + } /* else */ + ret = soread(so); + + /* Output it if we read something */ + if (ret > 0) { + tcp_output(sototcpcb(so)); + } + if (ret < 0) { + /* Socket error might have resulted in the socket being + * removed, do not try to do anything more with it. */ + continue; + } + } + + /* + * Check sockets for writing + */ + if (!(so->so_state & SS_NOFDREF) && + (revents & (SLIRP_POLL_OUT | SLIRP_POLL_ERR))) { + /* + * Check for non-blocking, still-connecting sockets + */ + if (so->so_state & SS_ISFCONNECTING) { + /* Connected */ + so->so_state &= ~SS_ISFCONNECTING; + + ret = send(so->s, (const void *) &ret, 0, 0); + if (ret < 0) { + /* XXXXX Must fix, zero bytes is a NOP */ + if (errno == EAGAIN || errno == EWOULDBLOCK || + errno == EINPROGRESS || errno == ENOTCONN) { + continue; + } + + /* else failed */ + so->so_state &= SS_PERSISTENT_MASK; + so->so_state |= SS_NOFDREF; + } + /* else so->so_state &= ~SS_ISFCONNECTING; */ + + /* + * Continue tcp_input + */ + tcp_input((struct mbuf *)NULL, sizeof(struct ip), so, + so->so_ffamily); + /* continue; */ + } else { + ret = sowrite(so); + if (ret > 0) { + /* Call tcp_output in case we need to send a window + * update to the guest, otherwise it will be stuck + * until it sends a window probe. */ + tcp_output(sototcpcb(so)); + } + } + } + } + + /* + * Now UDP sockets. + * Incoming packets are sent straight away, they're not buffered. + * Incoming UDP data isn't buffered either. + */ + for (so = slirp->udb.so_next; so != &slirp->udb; + so = so_next) { + int revents; + + so_next = so->so_next; + + revents = 0; + if (so->pollfds_idx != -1) { + revents = get_revents(so->pollfds_idx, opaque); + } + + if (so->s != -1 && + (revents & (SLIRP_POLL_IN | SLIRP_POLL_HUP | SLIRP_POLL_ERR))) { + sorecvfrom(so); + } + } + + /* + * Check incoming ICMP relies. + */ + for (so = slirp->icmp.so_next; so != &slirp->icmp; + so = so_next) { + int revents; + + so_next = so->so_next; + + revents = 0; + if (so->pollfds_idx != -1) { + revents = get_revents(so->pollfds_idx, opaque); + } + + if (so->s != -1 && + (revents & (SLIRP_POLL_IN | SLIRP_POLL_HUP | SLIRP_POLL_ERR))) { + icmp_receive(so); + } + } + } + + if_start(slirp); +} + +static void arp_input(Slirp *slirp, const uint8_t *pkt, int pkt_len) +{ + struct slirp_arphdr *ah = (struct slirp_arphdr *)(pkt + ETH_HLEN); + uint8_t arp_reply[MAX(ETH_HLEN + sizeof(struct slirp_arphdr), 64)]; + struct ethhdr *reh = (struct ethhdr *)arp_reply; + struct slirp_arphdr *rah = (struct slirp_arphdr *)(arp_reply + ETH_HLEN); + int ar_op; + struct gfwd_list *ex_ptr; + + if (!slirp->in_enabled) { + return; + } + + ar_op = ntohs(ah->ar_op); + switch(ar_op) { + case ARPOP_REQUEST: + if (ah->ar_tip == ah->ar_sip) { + /* Gratuitous ARP */ + arp_table_add(slirp, ah->ar_sip, ah->ar_sha); + return; + } + + if ((ah->ar_tip & slirp->vnetwork_mask.s_addr) == + slirp->vnetwork_addr.s_addr) { + if (ah->ar_tip == slirp->vnameserver_addr.s_addr || + ah->ar_tip == slirp->vhost_addr.s_addr) + goto arp_ok; + /* TODO: IPv6 */ + for (ex_ptr = slirp->guestfwd_list; ex_ptr; ex_ptr = ex_ptr->ex_next) { + if (ex_ptr->ex_addr.s_addr == ah->ar_tip) + goto arp_ok; + } + return; + arp_ok: + memset(arp_reply, 0, sizeof(arp_reply)); + + arp_table_add(slirp, ah->ar_sip, ah->ar_sha); + + /* ARP request for alias/dns mac address */ + memcpy(reh->h_dest, pkt + ETH_ALEN, ETH_ALEN); + memcpy(reh->h_source, special_ethaddr, ETH_ALEN - 4); + memcpy(&reh->h_source[2], &ah->ar_tip, 4); + reh->h_proto = htons(ETH_P_ARP); + + rah->ar_hrd = htons(1); + rah->ar_pro = htons(ETH_P_IP); + rah->ar_hln = ETH_ALEN; + rah->ar_pln = 4; + rah->ar_op = htons(ARPOP_REPLY); + memcpy(rah->ar_sha, reh->h_source, ETH_ALEN); + rah->ar_sip = ah->ar_tip; + memcpy(rah->ar_tha, ah->ar_sha, ETH_ALEN); + rah->ar_tip = ah->ar_sip; + slirp_send_packet_all(slirp, arp_reply, sizeof(arp_reply)); + } + break; + case ARPOP_REPLY: + arp_table_add(slirp, ah->ar_sip, ah->ar_sha); + break; + default: + break; + } +} + +void slirp_input(Slirp *slirp, const uint8_t *pkt, int pkt_len) +{ + struct mbuf *m; + int proto; + + if (pkt_len < ETH_HLEN) + return; + + proto = (((uint16_t) pkt[12]) << 8) + pkt[13]; + switch(proto) { + case ETH_P_ARP: + arp_input(slirp, pkt, pkt_len); + break; + case ETH_P_IP: + case ETH_P_IPV6: + m = m_get(slirp); + if (!m) + return; + /* Note: we add 2 to align the IP header on 4 bytes, + * and add the margin for the tcpiphdr overhead */ + if (M_FREEROOM(m) < pkt_len + TCPIPHDR_DELTA + 2) { + m_inc(m, pkt_len + TCPIPHDR_DELTA + 2); + } + m->m_len = pkt_len + TCPIPHDR_DELTA + 2; + memcpy(m->m_data + TCPIPHDR_DELTA + 2, pkt, pkt_len); + + m->m_data += TCPIPHDR_DELTA + 2 + ETH_HLEN; + m->m_len -= TCPIPHDR_DELTA + 2 + ETH_HLEN; + + if (proto == ETH_P_IP) { + ip_input(m); + } else if (proto == ETH_P_IPV6) { + ip6_input(m); + } + break; + + case ETH_P_NCSI: + ncsi_input(slirp, pkt, pkt_len); + break; + + default: + break; + } +} + +/* Prepare the IPv4 packet to be sent to the ethernet device. Returns 1 if no + * packet should be sent, 0 if the packet must be re-queued, 2 if the packet + * is ready to go. + */ +static int if_encap4(Slirp *slirp, struct mbuf *ifm, struct ethhdr *eh, + uint8_t ethaddr[ETH_ALEN]) +{ + const struct ip *iph = (const struct ip *)ifm->m_data; + + if (iph->ip_dst.s_addr == 0) { + /* 0.0.0.0 can not be a destination address, something went wrong, + * avoid making it worse */ + return 1; + } + if (!arp_table_search(slirp, iph->ip_dst.s_addr, ethaddr)) { + uint8_t arp_req[ETH_HLEN + sizeof(struct slirp_arphdr)]; + struct ethhdr *reh = (struct ethhdr *)arp_req; + struct slirp_arphdr *rah = (struct slirp_arphdr *)(arp_req + ETH_HLEN); + + if (!ifm->resolution_requested) { + /* If the client addr is not known, send an ARP request */ + memset(reh->h_dest, 0xff, ETH_ALEN); + memcpy(reh->h_source, special_ethaddr, ETH_ALEN - 4); + memcpy(&reh->h_source[2], &slirp->vhost_addr, 4); + reh->h_proto = htons(ETH_P_ARP); + rah->ar_hrd = htons(1); + rah->ar_pro = htons(ETH_P_IP); + rah->ar_hln = ETH_ALEN; + rah->ar_pln = 4; + rah->ar_op = htons(ARPOP_REQUEST); + + /* source hw addr */ + memcpy(rah->ar_sha, special_ethaddr, ETH_ALEN - 4); + memcpy(&rah->ar_sha[2], &slirp->vhost_addr, 4); + + /* source IP */ + rah->ar_sip = slirp->vhost_addr.s_addr; + + /* target hw addr (none) */ + memset(rah->ar_tha, 0, ETH_ALEN); + + /* target IP */ + rah->ar_tip = iph->ip_dst.s_addr; + slirp->client_ipaddr = iph->ip_dst; + slirp_send_packet_all(slirp, arp_req, sizeof(arp_req)); + ifm->resolution_requested = true; + + /* Expire request and drop outgoing packet after 1 second */ + ifm->expiration_date = + slirp->cb->clock_get_ns(slirp->opaque) + 1000000000ULL; + } + return 0; + } else { + memcpy(eh->h_source, special_ethaddr, ETH_ALEN - 4); + /* XXX: not correct */ + memcpy(&eh->h_source[2], &slirp->vhost_addr, 4); + eh->h_proto = htons(ETH_P_IP); + + /* Send this */ + return 2; + } +} + +/* Prepare the IPv6 packet to be sent to the ethernet device. Returns 1 if no + * packet should be sent, 0 if the packet must be re-queued, 2 if the packet + * is ready to go. + */ +static int if_encap6(Slirp *slirp, struct mbuf *ifm, struct ethhdr *eh, + uint8_t ethaddr[ETH_ALEN]) +{ + const struct ip6 *ip6h = mtod(ifm, const struct ip6 *); + if (!ndp_table_search(slirp, ip6h->ip_dst, ethaddr)) { + if (!ifm->resolution_requested) { + ndp_send_ns(slirp, ip6h->ip_dst); + ifm->resolution_requested = true; + ifm->expiration_date = slirp->cb->clock_get_ns(slirp->opaque) + 1000000000ULL; + } + return 0; + } else { + eh->h_proto = htons(ETH_P_IPV6); + in6_compute_ethaddr(ip6h->ip_src, eh->h_source); + + /* Send this */ + return 2; + } +} + +/* Output the IP packet to the ethernet device. Returns 0 if the packet must be + * re-queued. + */ +int if_encap(Slirp *slirp, struct mbuf *ifm) +{ + uint8_t buf[1600]; + struct ethhdr *eh = (struct ethhdr *)buf; + uint8_t ethaddr[ETH_ALEN]; + const struct ip *iph = (const struct ip *)ifm->m_data; + int ret; + + if (ifm->m_len + ETH_HLEN > sizeof(buf)) { + return 1; + } + + switch (iph->ip_v) { + case IPVERSION: + ret = if_encap4(slirp, ifm, eh, ethaddr); + if (ret < 2) { + return ret; + } + break; + + case IP6VERSION: + ret = if_encap6(slirp, ifm, eh, ethaddr); + if (ret < 2) { + return ret; + } + break; + + default: + g_assert_not_reached(); + break; + } + + memcpy(eh->h_dest, ethaddr, ETH_ALEN); + DEBUG_ARG("src = %02x:%02x:%02x:%02x:%02x:%02x", + eh->h_source[0], eh->h_source[1], eh->h_source[2], + eh->h_source[3], eh->h_source[4], eh->h_source[5]); + DEBUG_ARG("dst = %02x:%02x:%02x:%02x:%02x:%02x", + eh->h_dest[0], eh->h_dest[1], eh->h_dest[2], + eh->h_dest[3], eh->h_dest[4], eh->h_dest[5]); + memcpy(buf + sizeof(struct ethhdr), ifm->m_data, ifm->m_len); + slirp_send_packet_all(slirp, buf, ifm->m_len + ETH_HLEN); + return 1; +} + +/* Drop host forwarding rule, return 0 if found. */ +/* TODO: IPv6 */ +int slirp_remove_hostfwd(Slirp *slirp, int is_udp, struct in_addr host_addr, + int host_port) +{ + struct socket *so; + struct socket *head = (is_udp ? &slirp->udb : &slirp->tcb); + struct sockaddr_in addr; + int port = htons(host_port); + socklen_t addr_len; + + for (so = head->so_next; so != head; so = so->so_next) { + addr_len = sizeof(addr); + if ((so->so_state & SS_HOSTFWD) && + getsockname(so->s, (struct sockaddr *)&addr, &addr_len) == 0 && + addr.sin_addr.s_addr == host_addr.s_addr && + addr.sin_port == port) { + so->slirp->cb->unregister_poll_fd(so->s, so->slirp->opaque); + closesocket(so->s); + sofree(so); + return 0; + } + } + + return -1; +} + +/* TODO: IPv6 */ +int slirp_add_hostfwd(Slirp *slirp, int is_udp, struct in_addr host_addr, + int host_port, struct in_addr guest_addr, int guest_port) +{ + if (!guest_addr.s_addr) { + guest_addr = slirp->vdhcp_startaddr; + } + if (is_udp) { + if (!udp_listen(slirp, host_addr.s_addr, htons(host_port), + guest_addr.s_addr, htons(guest_port), SS_HOSTFWD)) + return -1; + } else { + if (!tcp_listen(slirp, host_addr.s_addr, htons(host_port), + guest_addr.s_addr, htons(guest_port), SS_HOSTFWD)) + return -1; + } + return 0; +} + +/* TODO: IPv6 */ +static bool +check_guestfwd(Slirp *slirp, struct in_addr *guest_addr, int guest_port) +{ + struct gfwd_list *tmp_ptr; + + if (!guest_addr->s_addr) { + guest_addr->s_addr = slirp->vnetwork_addr.s_addr | + (htonl(0x0204) & ~slirp->vnetwork_mask.s_addr); + } + if ((guest_addr->s_addr & slirp->vnetwork_mask.s_addr) != + slirp->vnetwork_addr.s_addr || + guest_addr->s_addr == slirp->vhost_addr.s_addr || + guest_addr->s_addr == slirp->vnameserver_addr.s_addr) { + return false; + } + + /* check if the port is "bound" */ + for (tmp_ptr = slirp->guestfwd_list; tmp_ptr; tmp_ptr = tmp_ptr->ex_next) { + if (guest_port == tmp_ptr->ex_fport && + guest_addr->s_addr == tmp_ptr->ex_addr.s_addr) + return false; + } + + return true; +} + +int slirp_add_exec(Slirp *slirp, const char *cmdline, + struct in_addr *guest_addr, int guest_port) +{ + if (!check_guestfwd(slirp, guest_addr, guest_port)) { + return -1; + } + + add_exec(&slirp->guestfwd_list, cmdline, *guest_addr, htons(guest_port)); + return 0; +} + +int slirp_add_guestfwd(Slirp *slirp, SlirpWriteCb write_cb, void *opaque, + struct in_addr *guest_addr, int guest_port) +{ + if (!check_guestfwd(slirp, guest_addr, guest_port)) { + return -1; + } + + add_guestfwd(&slirp->guestfwd_list, write_cb, opaque, + *guest_addr, htons(guest_port)); + return 0; +} + +ssize_t slirp_send(struct socket *so, const void *buf, size_t len, int flags) +{ + if (so->s == -1 && so->guestfwd) { + /* XXX this blocks entire thread. Rewrite to use + * qemu_chr_fe_write and background I/O callbacks */ + so->guestfwd->write_cb(buf, len, so->guestfwd->opaque); + return len; + } + + if (so->s == -1) { + /* + * This should in theory not happen but it is hard to be + * sure because some code paths will end up with so->s == -1 + * on a failure but don't dispose of the struct socket. + * Check specifically, so we don't pass -1 to send(). + */ + errno = EBADF; + return -1; + } + + return send(so->s, buf, len, flags); +} + +struct socket * +slirp_find_ctl_socket(Slirp *slirp, struct in_addr guest_addr, int guest_port) +{ + struct socket *so; + + /* TODO: IPv6 */ + for (so = slirp->tcb.so_next; so != &slirp->tcb; so = so->so_next) { + if (so->so_faddr.s_addr == guest_addr.s_addr && + htons(so->so_fport) == guest_port) { + return so; + } + } + return NULL; +} + +size_t slirp_socket_can_recv(Slirp *slirp, struct in_addr guest_addr, + int guest_port) +{ + struct iovec iov[2]; + struct socket *so; + + so = slirp_find_ctl_socket(slirp, guest_addr, guest_port); + + if (!so || so->so_state & SS_NOFDREF) { + return 0; + } + + if (!CONN_CANFRCV(so) || so->so_snd.sb_cc >= (so->so_snd.sb_datalen/2)) { + return 0; + } + + return sopreprbuf(so, iov, NULL); +} + +void slirp_socket_recv(Slirp *slirp, struct in_addr guest_addr, int guest_port, + const uint8_t *buf, int size) +{ + int ret; + struct socket *so = slirp_find_ctl_socket(slirp, guest_addr, guest_port); + + if (!so) + return; + + ret = soreadbuf(so, (const char *)buf, size); + + if (ret > 0) + tcp_output(sototcpcb(so)); +} + +void slirp_send_packet_all(Slirp *slirp, const void *buf, size_t len) +{ + ssize_t ret = slirp->cb->send_packet(buf, len, slirp->opaque); + + if (ret < 0) { + g_critical("Failed to send packet, ret: %ld", (long) ret); + } else if (ret < len) { + DEBUG_ERROR("send_packet() didn't send all data: %ld < %lu", + (long) ret, (unsigned long) len); + } +} |