/* * QEMU System Emulator * * Copyright (c) 2003-2008 Fabrice Bellard * Copyright (c) 2009 Red Hat, Inc. * * 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 "net/tap.h" #include "config-host.h" #include <signal.h> #include <sys/ioctl.h> #include <sys/stat.h> #include <sys/wait.h> #include <sys/socket.h> #include <net/if.h> #include "net.h" #include "sysemu.h" #include "qemu-char.h" #include "qemu-common.h" #include "net/tap-linux.h" /* Maximum GSO packet size (64k) plus plenty of room for * the ethernet and virtio_net headers */ #define TAP_BUFSIZE (4096 + 65536) typedef struct TAPState { VLANClientState nc; int fd; char down_script[1024]; char down_script_arg[128]; uint8_t buf[TAP_BUFSIZE]; unsigned int read_poll : 1; unsigned int write_poll : 1; unsigned int has_vnet_hdr : 1; unsigned int using_vnet_hdr : 1; unsigned int has_ufo: 1; } TAPState; static int launch_script(const char *setup_script, const char *ifname, int fd); static int tap_can_send(void *opaque); static void tap_send(void *opaque); static void tap_writable(void *opaque); static void tap_update_fd_handler(TAPState *s) { qemu_set_fd_handler2(s->fd, s->read_poll ? tap_can_send : NULL, s->read_poll ? tap_send : NULL, s->write_poll ? tap_writable : NULL, s); } static void tap_read_poll(TAPState *s, int enable) { s->read_poll = !!enable; tap_update_fd_handler(s); } static void tap_write_poll(TAPState *s, int enable) { s->write_poll = !!enable; tap_update_fd_handler(s); } static void tap_writable(void *opaque) { TAPState *s = opaque; tap_write_poll(s, 0); qemu_flush_queued_packets(&s->nc); } static ssize_t tap_write_packet(TAPState *s, const struct iovec *iov, int iovcnt) { ssize_t len; do { len = writev(s->fd, iov, iovcnt); } while (len == -1 && errno == EINTR); if (len == -1 && errno == EAGAIN) { tap_write_poll(s, 1); return 0; } return len; } static ssize_t tap_receive_iov(VLANClientState *nc, const struct iovec *iov, int iovcnt) { TAPState *s = DO_UPCAST(TAPState, nc, nc); const struct iovec *iovp = iov; struct iovec iov_copy[iovcnt + 1]; struct virtio_net_hdr hdr = { 0, }; if (s->has_vnet_hdr && !s->using_vnet_hdr) { iov_copy[0].iov_base = &hdr; iov_copy[0].iov_len = sizeof(hdr); memcpy(&iov_copy[1], iov, iovcnt * sizeof(*iov)); iovp = iov_copy; iovcnt++; } return tap_write_packet(s, iovp, iovcnt); } static ssize_t tap_receive_raw(VLANClientState *nc, const uint8_t *buf, size_t size) { TAPState *s = DO_UPCAST(TAPState, nc, nc); struct iovec iov[2]; int iovcnt = 0; struct virtio_net_hdr hdr = { 0, }; if (s->has_vnet_hdr) { iov[iovcnt].iov_base = &hdr; iov[iovcnt].iov_len = sizeof(hdr); iovcnt++; } iov[iovcnt].iov_base = (char *)buf; iov[iovcnt].iov_len = size; iovcnt++; return tap_write_packet(s, iov, iovcnt); } static ssize_t tap_receive(VLANClientState *nc, const uint8_t *buf, size_t size) { TAPState *s = DO_UPCAST(TAPState, nc, nc); struct iovec iov[1]; if (s->has_vnet_hdr && !s->using_vnet_hdr) { return tap_receive_raw(nc, buf, size); } iov[0].iov_base = (char *)buf; iov[0].iov_len = size; return tap_write_packet(s, iov, 1); } static int tap_can_send(void *opaque) { TAPState *s = opaque; return qemu_can_send_packet(&s->nc); } #ifndef __sun__ ssize_t tap_read_packet(int tapfd, uint8_t *buf, int maxlen) { return read(tapfd, buf, maxlen); } #endif static void tap_send_completed(VLANClientState *nc, ssize_t len) { TAPState *s = DO_UPCAST(TAPState, nc, nc); tap_read_poll(s, 1); } static void tap_send(void *opaque) { TAPState *s = opaque; int size; do { uint8_t *buf = s->buf; size = tap_read_packet(s->fd, s->buf, sizeof(s->buf)); if (size <= 0) { break; } if (s->has_vnet_hdr && !s->using_vnet_hdr) { buf += sizeof(struct virtio_net_hdr); size -= sizeof(struct virtio_net_hdr); } size = qemu_send_packet_async(&s->nc, buf, size, tap_send_completed); if (size == 0) { tap_read_poll(s, 0); } } while (size > 0 && qemu_can_send_packet(&s->nc)); } int tap_has_ufo(VLANClientState *nc) { TAPState *s = DO_UPCAST(TAPState, nc, nc); assert(nc->info->type == NET_CLIENT_TYPE_TAP); return s->has_ufo; } int tap_has_vnet_hdr(VLANClientState *nc) { TAPState *s = DO_UPCAST(TAPState, nc, nc); assert(nc->info->type == NET_CLIENT_TYPE_TAP); return s->has_vnet_hdr; } void tap_using_vnet_hdr(VLANClientState *nc, int using_vnet_hdr) { TAPState *s = DO_UPCAST(TAPState, nc, nc); using_vnet_hdr = using_vnet_hdr != 0; assert(nc->info->type == NET_CLIENT_TYPE_TAP); assert(s->has_vnet_hdr == using_vnet_hdr); s->using_vnet_hdr = using_vnet_hdr; } void tap_set_offload(VLANClientState *nc, int csum, int tso4, int tso6, int ecn, int ufo) { TAPState *s = DO_UPCAST(TAPState, nc, nc); return tap_fd_set_offload(s->fd, csum, tso4, tso6, ecn, ufo); } static void tap_cleanup(VLANClientState *nc) { TAPState *s = DO_UPCAST(TAPState, nc, nc); qemu_purge_queued_packets(nc); if (s->down_script[0]) launch_script(s->down_script, s->down_script_arg, s->fd); tap_read_poll(s, 0); tap_write_poll(s, 0); close(s->fd); } /* fd support */ static NetClientInfo net_tap_info = { .type = NET_CLIENT_TYPE_TAP, .size = sizeof(TAPState), .receive = tap_receive, .receive_raw = tap_receive_raw, .receive_iov = tap_receive_iov, .cleanup = tap_cleanup, }; static TAPState *net_tap_fd_init(VLANState *vlan, const char *model, const char *name, int fd, int vnet_hdr) { VLANClientState *nc; TAPState *s; nc = qemu_new_net_client(&net_tap_info, vlan, NULL, model, name); s = DO_UPCAST(TAPState, nc, nc); s->fd = fd; s->has_vnet_hdr = vnet_hdr != 0; s->using_vnet_hdr = 0; s->has_ufo = tap_probe_has_ufo(s->fd); tap_set_offload(&s->nc, 0, 0, 0, 0, 0); tap_read_poll(s, 1); return s; } static int launch_script(const char *setup_script, const char *ifname, int fd) { sigset_t oldmask, mask; int pid, status; char *args[3]; char **parg; sigemptyset(&mask); sigaddset(&mask, SIGCHLD); sigprocmask(SIG_BLOCK, &mask, &oldmask); /* try to launch network script */ pid = fork(); if (pid == 0) { int open_max = sysconf(_SC_OPEN_MAX), i; for (i = 0; i < open_max; i++) { if (i != STDIN_FILENO && i != STDOUT_FILENO && i != STDERR_FILENO && i != fd) { close(i); } } parg = args; *parg++ = (char *)setup_script; *parg++ = (char *)ifname; *parg++ = NULL; execv(setup_script, args); _exit(1); } else if (pid > 0) { while (waitpid(pid, &status, 0) != pid) { /* loop */ } sigprocmask(SIG_SETMASK, &oldmask, NULL); if (WIFEXITED(status) && WEXITSTATUS(status) == 0) { return 0; } } fprintf(stderr, "%s: could not launch network script\n", setup_script); return -1; } static int net_tap_init(QemuOpts *opts, int *vnet_hdr) { int fd, vnet_hdr_required; char ifname[128] = {0,}; const char *setup_script; if (qemu_opt_get(opts, "ifname")) { pstrcpy(ifname, sizeof(ifname), qemu_opt_get(opts, "ifname")); } *vnet_hdr = qemu_opt_get_bool(opts, "vnet_hdr", 1); if (qemu_opt_get(opts, "vnet_hdr")) { vnet_hdr_required = *vnet_hdr; } else { vnet_hdr_required = 0; } TFR(fd = tap_open(ifname, sizeof(ifname), vnet_hdr, vnet_hdr_required)); if (fd < 0) { return -1; } setup_script = qemu_opt_get(opts, "script"); if (setup_script && setup_script[0] != '\0' && strcmp(setup_script, "no") != 0 && launch_script(setup_script, ifname, fd)) { close(fd); return -1; } qemu_opt_set(opts, "ifname", ifname); return fd; } int net_init_tap(QemuOpts *opts, Monitor *mon, const char *name, VLANState *vlan) { TAPState *s; int fd, vnet_hdr = 0; if (qemu_opt_get(opts, "fd")) { if (qemu_opt_get(opts, "ifname") || qemu_opt_get(opts, "script") || qemu_opt_get(opts, "downscript") || qemu_opt_get(opts, "vnet_hdr")) { qemu_error("ifname=, script=, downscript= and vnet_hdr= is invalid with fd=\n"); return -1; } fd = net_handle_fd_param(mon, qemu_opt_get(opts, "fd")); if (fd == -1) { return -1; } fcntl(fd, F_SETFL, O_NONBLOCK); vnet_hdr = tap_probe_vnet_hdr(fd); } else { if (!qemu_opt_get(opts, "script")) { qemu_opt_set(opts, "script", DEFAULT_NETWORK_SCRIPT); } if (!qemu_opt_get(opts, "downscript")) { qemu_opt_set(opts, "downscript", DEFAULT_NETWORK_DOWN_SCRIPT); } fd = net_tap_init(opts, &vnet_hdr); if (fd == -1) { return -1; } } s = net_tap_fd_init(vlan, "tap", name, fd, vnet_hdr); if (!s) { close(fd); return -1; } if (tap_set_sndbuf(s->fd, opts) < 0) { return -1; } if (qemu_opt_get(opts, "fd")) { snprintf(s->nc.info_str, sizeof(s->nc.info_str), "fd=%d", fd); } else { const char *ifname, *script, *downscript; ifname = qemu_opt_get(opts, "ifname"); script = qemu_opt_get(opts, "script"); downscript = qemu_opt_get(opts, "downscript"); snprintf(s->nc.info_str, sizeof(s->nc.info_str), "ifname=%s,script=%s,downscript=%s", ifname, script, downscript); if (strcmp(downscript, "no") != 0) { snprintf(s->down_script, sizeof(s->down_script), "%s", downscript); snprintf(s->down_script_arg, sizeof(s->down_script_arg), "%s", ifname); } } if (vlan) { vlan->nb_host_devs++; } return 0; }