net: move net.c to net/

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

2 files changed, 1057 insertions, 1 deletions

diff --git a/net/Makefile.objs b/net/Makefile.objs
index cf04187..a08cd14 100644
--- a/net/Makefile.objs
+++ b/net/Makefile.objs
@@ -1,4 +1,4 @@
-common-obj-y = queue.o checksum.o util.o hub.o
+common-obj-y = net.o queue.o checksum.o util.o hub.o
 common-obj-y += socket.o
 common-obj-y += dump.o
 common-obj-$(CONFIG_POSIX) += tap.o
diff --git a/net/net.c b/net/net.c
new file mode 100644
index 0000000..7b1600f
--- /dev/null
+++ b/net/net.c
@@ -0,0 +1,1056 @@
+/*
+ * QEMU System Emulator
+ *
+ * Copyright (c) 2003-2008 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 "config-host.h"
+
+#include "net.h"
+#include "clients.h"
+#include "hub.h"
+#include "slirp.h"
+#include "util.h"
+
+#include "monitor.h"
+#include "qemu-common.h"
+#include "qemu_socket.h"
+#include "qemu-config.h"
+#include "qmp-commands.h"
+#include "hw/qdev.h"
+#include "iov.h"
+#include "qapi-visit.h"
+#include "qapi/opts-visitor.h"
+#include "qapi/qapi-dealloc-visitor.h"
+
+/* Net bridge is currently not supported for W32. */
+#if !defined(_WIN32)
+# define CONFIG_NET_BRIDGE
+#endif
+
+static QTAILQ_HEAD(, NetClientState) net_clients;
+
+int default_net = 1;
+
+/***********************************************************/
+/* network device redirectors */
+
+#if defined(DEBUG_NET)
+static void hex_dump(FILE *f, const uint8_t *buf, int size)
+{
+    int len, i, j, c;
+
+    for(i=0;i<size;i+=16) {
+        len = size - i;
+        if (len > 16)
+            len = 16;
+        fprintf(f, "%08x ", i);
+        for(j=0;j<16;j++) {
+            if (j < len)
+                fprintf(f, " %02x", buf[i+j]);
+            else
+                fprintf(f, "   ");
+        }
+        fprintf(f, " ");
+        for(j=0;j<len;j++) {
+            c = buf[i+j];
+            if (c < ' ' || c > '~')
+                c = '.';
+            fprintf(f, "%c", c);
+        }
+        fprintf(f, "\n");
+    }
+}
+#endif
+
+static int get_str_sep(char *buf, int buf_size, const char **pp, int sep)
+{
+    const char *p, *p1;
+    int len;
+    p = *pp;
+    p1 = strchr(p, sep);
+    if (!p1)
+        return -1;
+    len = p1 - p;
+    p1++;
+    if (buf_size > 0) {
+        if (len > buf_size - 1)
+            len = buf_size - 1;
+        memcpy(buf, p, len);
+        buf[len] = '\0';
+    }
+    *pp = p1;
+    return 0;
+}
+
+int parse_host_port(struct sockaddr_in *saddr, const char *str)
+{
+    char buf[512];
+    struct hostent *he;
+    const char *p, *r;
+    int port;
+
+    p = str;
+    if (get_str_sep(buf, sizeof(buf), &p, ':') < 0)
+        return -1;
+    saddr->sin_family = AF_INET;
+    if (buf[0] == '\0') {
+        saddr->sin_addr.s_addr = 0;
+    } else {
+        if (qemu_isdigit(buf[0])) {
+            if (!inet_aton(buf, &saddr->sin_addr))
+                return -1;
+        } else {
+            if ((he = gethostbyname(buf)) == NULL)
+                return - 1;
+            saddr->sin_addr = *(struct in_addr *)he->h_addr;
+        }
+    }
+    port = strtol(p, (char **)&r, 0);
+    if (r == p)
+        return -1;
+    saddr->sin_port = htons(port);
+    return 0;
+}
+
+void qemu_format_nic_info_str(NetClientState *nc, uint8_t macaddr[6])
+{
+    snprintf(nc->info_str, sizeof(nc->info_str),
+             "model=%s,macaddr=%02x:%02x:%02x:%02x:%02x:%02x",
+             nc->model,
+             macaddr[0], macaddr[1], macaddr[2],
+             macaddr[3], macaddr[4], macaddr[5]);
+}
+
+void qemu_macaddr_default_if_unset(MACAddr *macaddr)
+{
+    static int index = 0;
+    static const MACAddr zero = { .a = { 0,0,0,0,0,0 } };
+
+    if (memcmp(macaddr, &zero, sizeof(zero)) != 0)
+        return;
+    macaddr->a[0] = 0x52;
+    macaddr->a[1] = 0x54;
+    macaddr->a[2] = 0x00;
+    macaddr->a[3] = 0x12;
+    macaddr->a[4] = 0x34;
+    macaddr->a[5] = 0x56 + index++;
+}
+
+/**
+ * Generate a name for net client
+ *
+ * Only net clients created with the legacy -net option need this.  Naming is
+ * mandatory for net clients created with -netdev.
+ */
+static char *assign_name(NetClientState *nc1, const char *model)
+{
+    NetClientState *nc;
+    char buf[256];
+    int id = 0;
+
+    QTAILQ_FOREACH(nc, &net_clients, next) {
+        if (nc == nc1) {
+            continue;
+        }
+        /* For compatibility only bump id for net clients on a vlan */
+        if (strcmp(nc->model, model) == 0 &&
+            net_hub_id_for_client(nc, NULL) == 0) {
+            id++;
+        }
+    }
+
+    snprintf(buf, sizeof(buf), "%s.%d", model, id);
+
+    return g_strdup(buf);
+}
+
+NetClientState *qemu_new_net_client(NetClientInfo *info,
+                                    NetClientState *peer,
+                                    const char *model,
+                                    const char *name)
+{
+    NetClientState *nc;
+
+    assert(info->size >= sizeof(NetClientState));
+
+    nc = g_malloc0(info->size);
+
+    nc->info = info;
+    nc->model = g_strdup(model);
+    if (name) {
+        nc->name = g_strdup(name);
+    } else {
+        nc->name = assign_name(nc, model);
+    }
+
+    if (peer) {
+        assert(!peer->peer);
+        nc->peer = peer;
+        peer->peer = nc;
+    }
+    QTAILQ_INSERT_TAIL(&net_clients, nc, next);
+
+    nc->send_queue = qemu_new_net_queue(nc);
+
+    return nc;
+}
+
+NICState *qemu_new_nic(NetClientInfo *info,
+                       NICConf *conf,
+                       const char *model,
+                       const char *name,
+                       void *opaque)
+{
+    NetClientState *nc;
+    NICState *nic;
+
+    assert(info->type == NET_CLIENT_OPTIONS_KIND_NIC);
+    assert(info->size >= sizeof(NICState));
+
+    nc = qemu_new_net_client(info, conf->peer, model, name);
+
+    nic = DO_UPCAST(NICState, nc, nc);
+    nic->conf = conf;
+    nic->opaque = opaque;
+
+    return nic;
+}
+
+static void qemu_cleanup_net_client(NetClientState *nc)
+{
+    QTAILQ_REMOVE(&net_clients, nc, next);
+
+    if (nc->info->cleanup) {
+        nc->info->cleanup(nc);
+    }
+}
+
+static void qemu_free_net_client(NetClientState *nc)
+{
+    if (nc->send_queue) {
+        qemu_del_net_queue(nc->send_queue);
+    }
+    if (nc->peer) {
+        nc->peer->peer = NULL;
+    }
+    g_free(nc->name);
+    g_free(nc->model);
+    g_free(nc);
+}
+
+void qemu_del_net_client(NetClientState *nc)
+{
+    /* If there is a peer NIC, delete and cleanup client, but do not free. */
+    if (nc->peer && nc->peer->info->type == NET_CLIENT_OPTIONS_KIND_NIC) {
+        NICState *nic = DO_UPCAST(NICState, nc, nc->peer);
+        if (nic->peer_deleted) {
+            return;
+        }
+        nic->peer_deleted = true;
+        /* Let NIC know peer is gone. */
+        nc->peer->link_down = true;
+        if (nc->peer->info->link_status_changed) {
+            nc->peer->info->link_status_changed(nc->peer);
+        }
+        qemu_cleanup_net_client(nc);
+        return;
+    }
+
+    /* If this is a peer NIC and peer has already been deleted, free it now. */
+    if (nc->peer && nc->info->type == NET_CLIENT_OPTIONS_KIND_NIC) {
+        NICState *nic = DO_UPCAST(NICState, nc, nc);
+        if (nic->peer_deleted) {
+            qemu_free_net_client(nc->peer);
+        }
+    }
+
+    qemu_cleanup_net_client(nc);
+    qemu_free_net_client(nc);
+}
+
+void qemu_foreach_nic(qemu_nic_foreach func, void *opaque)
+{
+    NetClientState *nc;
+
+    QTAILQ_FOREACH(nc, &net_clients, next) {
+        if (nc->info->type == NET_CLIENT_OPTIONS_KIND_NIC) {
+            func(DO_UPCAST(NICState, nc, nc), opaque);
+        }
+    }
+}
+
+int qemu_can_send_packet(NetClientState *sender)
+{
+    if (!sender->peer) {
+        return 1;
+    }
+
+    if (sender->peer->receive_disabled) {
+        return 0;
+    } else if (sender->peer->info->can_receive &&
+               !sender->peer->info->can_receive(sender->peer)) {
+        return 0;
+    }
+    return 1;
+}
+
+ssize_t qemu_deliver_packet(NetClientState *sender,
+                            unsigned flags,
+                            const uint8_t *data,
+                            size_t size,
+                            void *opaque)
+{
+    NetClientState *nc = opaque;
+    ssize_t ret;
+
+    if (nc->link_down) {
+        return size;
+    }
+
+    if (nc->receive_disabled) {
+        return 0;
+    }
+
+    if (flags & QEMU_NET_PACKET_FLAG_RAW && nc->info->receive_raw) {
+        ret = nc->info->receive_raw(nc, data, size);
+    } else {
+        ret = nc->info->receive(nc, data, size);
+    }
+
+    if (ret == 0) {
+        nc->receive_disabled = 1;
+    };
+
+    return ret;
+}
+
+void qemu_purge_queued_packets(NetClientState *nc)
+{
+    if (!nc->peer) {
+        return;
+    }
+
+    qemu_net_queue_purge(nc->peer->send_queue, nc);
+}
+
+void qemu_flush_queued_packets(NetClientState *nc)
+{
+    nc->receive_disabled = 0;
+
+    if (qemu_net_queue_flush(nc->send_queue)) {
+        /* We emptied the queue successfully, signal to the IO thread to repoll
+         * the file descriptor (for tap, for example).
+         */
+        qemu_notify_event();
+    }
+}
+
+static ssize_t qemu_send_packet_async_with_flags(NetClientState *sender,
+                                                 unsigned flags,
+                                                 const uint8_t *buf, int size,
+                                                 NetPacketSent *sent_cb)
+{
+    NetQueue *queue;
+
+#ifdef DEBUG_NET
+    printf("qemu_send_packet_async:\n");
+    hex_dump(stdout, buf, size);
+#endif
+
+    if (sender->link_down || !sender->peer) {
+        return size;
+    }
+
+    queue = sender->peer->send_queue;
+
+    return qemu_net_queue_send(queue, sender, flags, buf, size, sent_cb);
+}
+
+ssize_t qemu_send_packet_async(NetClientState *sender,
+                               const uint8_t *buf, int size,
+                               NetPacketSent *sent_cb)
+{
+    return qemu_send_packet_async_with_flags(sender, QEMU_NET_PACKET_FLAG_NONE,
+                                             buf, size, sent_cb);
+}
+
+void qemu_send_packet(NetClientState *nc, const uint8_t *buf, int size)
+{
+    qemu_send_packet_async(nc, buf, size, NULL);
+}
+
+ssize_t qemu_send_packet_raw(NetClientState *nc, const uint8_t *buf, int size)
+{
+    return qemu_send_packet_async_with_flags(nc, QEMU_NET_PACKET_FLAG_RAW,
+                                             buf, size, NULL);
+}
+
+static ssize_t nc_sendv_compat(NetClientState *nc, const struct iovec *iov,
+                               int iovcnt)
+{
+    uint8_t buffer[4096];
+    size_t offset;
+
+    offset = iov_to_buf(iov, iovcnt, 0, buffer, sizeof(buffer));
+
+    return nc->info->receive(nc, buffer, offset);
+}
+
+ssize_t qemu_deliver_packet_iov(NetClientState *sender,
+                                unsigned flags,
+                                const struct iovec *iov,
+                                int iovcnt,
+                                void *opaque)
+{
+    NetClientState *nc = opaque;
+    int ret;
+
+    if (nc->link_down) {
+        return iov_size(iov, iovcnt);
+    }
+
+    if (nc->receive_disabled) {
+        return 0;
+    }
+
+    if (nc->info->receive_iov) {
+        ret = nc->info->receive_iov(nc, iov, iovcnt);
+    } else {
+        ret = nc_sendv_compat(nc, iov, iovcnt);
+    }
+
+    if (ret == 0) {
+        nc->receive_disabled = 1;
+    }
+
+    return ret;
+}
+
+ssize_t qemu_sendv_packet_async(NetClientState *sender,
+                                const struct iovec *iov, int iovcnt,
+                                NetPacketSent *sent_cb)
+{
+    NetQueue *queue;
+
+    if (sender->link_down || !sender->peer) {
+        return iov_size(iov, iovcnt);
+    }
+
+    queue = sender->peer->send_queue;
+
+    return qemu_net_queue_send_iov(queue, sender,
+                                   QEMU_NET_PACKET_FLAG_NONE,
+                                   iov, iovcnt, sent_cb);
+}
+
+ssize_t
+qemu_sendv_packet(NetClientState *nc, const struct iovec *iov, int iovcnt)
+{
+    return qemu_sendv_packet_async(nc, iov, iovcnt, NULL);
+}
+
+NetClientState *qemu_find_netdev(const char *id)
+{
+    NetClientState *nc;
+
+    QTAILQ_FOREACH(nc, &net_clients, next) {
+        if (nc->info->type == NET_CLIENT_OPTIONS_KIND_NIC)
+            continue;
+        if (!strcmp(nc->name, id)) {
+            return nc;
+        }
+    }
+
+    return NULL;
+}
+
+static int nic_get_free_idx(void)
+{
+    int index;
+
+    for (index = 0; index < MAX_NICS; index++)
+        if (!nd_table[index].used)
+            return index;
+    return -1;
+}
+
+int qemu_show_nic_models(const char *arg, const char *const *models)
+{
+    int i;
+
+    if (!arg || !is_help_option(arg)) {
+        return 0;
+    }
+
+    fprintf(stderr, "qemu: Supported NIC models: ");
+    for (i = 0 ; models[i]; i++)
+        fprintf(stderr, "%s%c", models[i], models[i+1] ? ',' : '\n');
+    return 1;
+}
+
+void qemu_check_nic_model(NICInfo *nd, const char *model)
+{
+    const char *models[2];
+
+    models[0] = model;
+    models[1] = NULL;
+
+    if (qemu_show_nic_models(nd->model, models))
+        exit(0);
+    if (qemu_find_nic_model(nd, models, model) < 0)
+        exit(1);
+}
+
+int qemu_find_nic_model(NICInfo *nd, const char * const *models,
+                        const char *default_model)
+{
+    int i;
+
+    if (!nd->model)
+        nd->model = g_strdup(default_model);
+
+    for (i = 0 ; models[i]; i++) {
+        if (strcmp(nd->model, models[i]) == 0)
+            return i;
+    }
+
+    error_report("Unsupported NIC model: %s", nd->model);
+    return -1;
+}
+
+static int net_init_nic(const NetClientOptions *opts, const char *name,
+                        NetClientState *peer)
+{
+    int idx;
+    NICInfo *nd;
+    const NetLegacyNicOptions *nic;
+
+    assert(opts->kind == NET_CLIENT_OPTIONS_KIND_NIC);
+    nic = opts->nic;
+
+    idx = nic_get_free_idx();
+    if (idx == -1 || nb_nics >= MAX_NICS) {
+        error_report("Too Many NICs");
+        return -1;
+    }
+
+    nd = &nd_table[idx];
+
+    memset(nd, 0, sizeof(*nd));
+
+    if (nic->has_netdev) {
+        nd->netdev = qemu_find_netdev(nic->netdev);
+        if (!nd->netdev) {
+            error_report("netdev '%s' not found", nic->netdev);
+            return -1;
+        }
+    } else {
+        assert(peer);
+        nd->netdev = peer;
+    }
+    if (name) {
+        nd->name = g_strdup(name);
+    }
+    if (nic->has_model) {
+        nd->model = g_strdup(nic->model);
+    }
+    if (nic->has_addr) {
+        nd->devaddr = g_strdup(nic->addr);
+    }
+
+    if (nic->has_macaddr &&
+        net_parse_macaddr(nd->macaddr.a, nic->macaddr) < 0) {
+        error_report("invalid syntax for ethernet address");
+        return -1;
+    }
+    qemu_macaddr_default_if_unset(&nd->macaddr);
+
+    if (nic->has_vectors) {
+        if (nic->vectors > 0x7ffffff) {
+            error_report("invalid # of vectors: %"PRIu32, nic->vectors);
+            return -1;
+        }
+        nd->nvectors = nic->vectors;
+    } else {
+        nd->nvectors = DEV_NVECTORS_UNSPECIFIED;
+    }
+
+    nd->used = 1;
+    nb_nics++;
+
+    return idx;
+}
+
+
+static int (* const net_client_init_fun[NET_CLIENT_OPTIONS_KIND_MAX])(
+    const NetClientOptions *opts,
+    const char *name,
+    NetClientState *peer) = {
+        [NET_CLIENT_OPTIONS_KIND_NIC]       = net_init_nic,
+#ifdef CONFIG_SLIRP
+        [NET_CLIENT_OPTIONS_KIND_USER]      = net_init_slirp,
+#endif
+        [NET_CLIENT_OPTIONS_KIND_TAP]       = net_init_tap,
+        [NET_CLIENT_OPTIONS_KIND_SOCKET]    = net_init_socket,
+#ifdef CONFIG_VDE
+        [NET_CLIENT_OPTIONS_KIND_VDE]       = net_init_vde,
+#endif
+        [NET_CLIENT_OPTIONS_KIND_DUMP]      = net_init_dump,
+#ifdef CONFIG_NET_BRIDGE
+        [NET_CLIENT_OPTIONS_KIND_BRIDGE]    = net_init_bridge,
+#endif
+        [NET_CLIENT_OPTIONS_KIND_HUBPORT]   = net_init_hubport,
+};
+
+
+static int net_client_init1(const void *object, int is_netdev, Error **errp)
+{
+    union {
+        const Netdev    *netdev;
+        const NetLegacy *net;
+    } u;
+    const NetClientOptions *opts;
+    const char *name;
+
+    if (is_netdev) {
+        u.netdev = object;
+        opts = u.netdev->opts;
+        name = u.netdev->id;
+
+        switch (opts->kind) {
+#ifdef CONFIG_SLIRP
+        case NET_CLIENT_OPTIONS_KIND_USER:
+#endif
+        case NET_CLIENT_OPTIONS_KIND_TAP:
+        case NET_CLIENT_OPTIONS_KIND_SOCKET:
+#ifdef CONFIG_VDE
+        case NET_CLIENT_OPTIONS_KIND_VDE:
+#endif
+#ifdef CONFIG_NET_BRIDGE
+        case NET_CLIENT_OPTIONS_KIND_BRIDGE:
+#endif
+        case NET_CLIENT_OPTIONS_KIND_HUBPORT:
+            break;
+
+        default:
+            error_set(errp, QERR_INVALID_PARAMETER_VALUE, "type",
+                      "a netdev backend type");
+            return -1;
+        }
+    } else {
+        u.net = object;
+        opts = u.net->opts;
+        /* missing optional values have been initialized to "all bits zero" */
+        name = u.net->has_id ? u.net->id : u.net->name;
+    }
+
+    if (net_client_init_fun[opts->kind]) {
+        NetClientState *peer = NULL;
+
+        /* Do not add to a vlan if it's a -netdev or a nic with a netdev=
+         * parameter. */
+        if (!is_netdev &&
+            (opts->kind != NET_CLIENT_OPTIONS_KIND_NIC ||
+             !opts->nic->has_netdev)) {
+            peer = net_hub_add_port(u.net->has_vlan ? u.net->vlan : 0, NULL);
+        }
+
+        if (net_client_init_fun[opts->kind](opts, name, peer) < 0) {
+            /* TODO push error reporting into init() methods */
+            error_set(errp, QERR_DEVICE_INIT_FAILED,
+                      NetClientOptionsKind_lookup[opts->kind]);
+            return -1;
+        }
+    }
+    return 0;
+}
+
+
+static void net_visit(Visitor *v, int is_netdev, void **object, Error **errp)
+{
+    if (is_netdev) {
+        visit_type_Netdev(v, (Netdev **)object, NULL, errp);
+    } else {
+        visit_type_NetLegacy(v, (NetLegacy **)object, NULL, errp);
+    }
+}
+
+
+int net_client_init(QemuOpts *opts, int is_netdev, Error **errp)
+{
+    void *object = NULL;
+    Error *err = NULL;
+    int ret = -1;
+
+    {
+        OptsVisitor *ov = opts_visitor_new(opts);
+
+        net_visit(opts_get_visitor(ov), is_netdev, &object, &err);
+        opts_visitor_cleanup(ov);
+    }
+
+    if (!err) {
+        ret = net_client_init1(object, is_netdev, &err);
+    }
+
+    if (object) {
+        QapiDeallocVisitor *dv = qapi_dealloc_visitor_new();
+
+        net_visit(qapi_dealloc_get_visitor(dv), is_netdev, &object, NULL);
+        qapi_dealloc_visitor_cleanup(dv);
+    }
+
+    error_propagate(errp, err);
+    return ret;
+}
+
+
+static int net_host_check_device(const char *device)
+{
+    int i;
+    const char *valid_param_list[] = { "tap", "socket", "dump"
+#ifdef CONFIG_NET_BRIDGE
+                                       , "bridge"
+#endif
+#ifdef CONFIG_SLIRP
+                                       ,"user"
+#endif
+#ifdef CONFIG_VDE
+                                       ,"vde"
+#endif
+    };
+    for (i = 0; i < sizeof(valid_param_list) / sizeof(char *); i++) {
+        if (!strncmp(valid_param_list[i], device,
+                     strlen(valid_param_list[i])))
+            return 1;
+    }
+
+    return 0;
+}
+
+void net_host_device_add(Monitor *mon, const QDict *qdict)
+{
+    const char *device = qdict_get_str(qdict, "device");
+    const char *opts_str = qdict_get_try_str(qdict, "opts");
+    Error *local_err = NULL;
+    QemuOpts *opts;
+
+    if (!net_host_check_device(device)) {
+        monitor_printf(mon, "invalid host network device %s\n", device);
+        return;
+    }
+
+    opts = qemu_opts_parse(qemu_find_opts("net"), opts_str ? opts_str : "", 0);
+    if (!opts) {
+        return;
+    }
+
+    qemu_opt_set(opts, "type", device);
+
+    net_client_init(opts, 0, &local_err);
+    if (error_is_set(&local_err)) {
+        qerror_report_err(local_err);
+        error_free(local_err);
+        monitor_printf(mon, "adding host network device %s failed\n", device);
+    }
+}
+
+void net_host_device_remove(Monitor *mon, const QDict *qdict)
+{
+    NetClientState *nc;
+    int vlan_id = qdict_get_int(qdict, "vlan_id");
+    const char *device = qdict_get_str(qdict, "device");
+
+    nc = net_hub_find_client_by_name(vlan_id, device);
+    if (!nc) {
+        return;
+    }
+    if (!net_host_check_device(nc->model)) {
+        monitor_printf(mon, "invalid host network device %s\n", device);
+        return;
+    }
+    qemu_del_net_client(nc);
+}
+
+void netdev_add(QemuOpts *opts, Error **errp)
+{
+    net_client_init(opts, 1, errp);
+}
+
+int qmp_netdev_add(Monitor *mon, const QDict *qdict, QObject **ret)
+{
+    Error *local_err = NULL;
+    QemuOptsList *opts_list;
+    QemuOpts *opts;
+
+    opts_list = qemu_find_opts_err("netdev", &local_err);
+    if (error_is_set(&local_err)) {
+        goto exit_err;
+    }
+
+    opts = qemu_opts_from_qdict(opts_list, qdict, &local_err);
+    if (error_is_set(&local_err)) {
+        goto exit_err;
+    }
+
+    netdev_add(opts, &local_err);
+    if (error_is_set(&local_err)) {
+        qemu_opts_del(opts);
+        goto exit_err;
+    }
+
+    return 0;
+
+exit_err:
+    qerror_report_err(local_err);
+    error_free(local_err);
+    return -1;
+}
+
+void qmp_netdev_del(const char *id, Error **errp)
+{
+    NetClientState *nc;
+    QemuOpts *opts;
+
+    nc = qemu_find_netdev(id);
+    if (!nc) {
+        error_set(errp, QERR_DEVICE_NOT_FOUND, id);
+        return;
+    }
+
+    opts = qemu_opts_find(qemu_find_opts_err("netdev", NULL), id);
+    if (!opts) {
+        error_setg(errp, "Device '%s' is not a netdev", id);
+        return;
+    }
+
+    qemu_del_net_client(nc);
+    qemu_opts_del(opts);
+}
+
+void print_net_client(Monitor *mon, NetClientState *nc)
+{
+    monitor_printf(mon, "%s: type=%s,%s\n", nc->name,
+                   NetClientOptionsKind_lookup[nc->info->type], nc->info_str);
+}
+
+void do_info_network(Monitor *mon)
+{
+    NetClientState *nc, *peer;
+    NetClientOptionsKind type;
+
+    net_hub_info(mon);
+
+    QTAILQ_FOREACH(nc, &net_clients, next) {
+        peer = nc->peer;
+        type = nc->info->type;
+
+        /* Skip if already printed in hub info */
+        if (net_hub_id_for_client(nc, NULL) == 0) {
+            continue;
+        }
+
+        if (!peer || type == NET_CLIENT_OPTIONS_KIND_NIC) {
+            print_net_client(mon, nc);
+        } /* else it's a netdev connected to a NIC, printed with the NIC */
+        if (peer && type == NET_CLIENT_OPTIONS_KIND_NIC) {
+            monitor_printf(mon, " \\ ");
+            print_net_client(mon, peer);
+        }
+    }
+}
+
+void qmp_set_link(const char *name, bool up, Error **errp)
+{
+    NetClientState *nc = NULL;
+
+    QTAILQ_FOREACH(nc, &net_clients, next) {
+        if (!strcmp(nc->name, name)) {
+            goto done;
+        }
+    }
+done:
+    if (!nc) {
+        error_set(errp, QERR_DEVICE_NOT_FOUND, name);
+        return;
+    }
+
+    nc->link_down = !up;
+
+    if (nc->info->link_status_changed) {
+        nc->info->link_status_changed(nc);
+    }
+
+    /* Notify peer. Don't update peer link status: this makes it possible to
+     * disconnect from host network without notifying the guest.
+     * FIXME: is disconnected link status change operation useful?
+     *
+     * Current behaviour is compatible with qemu vlans where there could be
+     * multiple clients that can still communicate with each other in
+     * disconnected mode. For now maintain this compatibility. */
+    if (nc->peer && nc->peer->info->link_status_changed) {
+        nc->peer->info->link_status_changed(nc->peer);
+    }
+}
+
+void net_cleanup(void)
+{
+    NetClientState *nc, *next_vc;
+
+    QTAILQ_FOREACH_SAFE(nc, &net_clients, next, next_vc) {
+        qemu_del_net_client(nc);
+    }
+}
+
+void net_check_clients(void)
+{
+    NetClientState *nc;
+    int i;
+
+    /* Don't warn about the default network setup that you get if
+     * no command line -net or -netdev options are specified. There
+     * are two cases that we would otherwise complain about:
+     * (1) board doesn't support a NIC but the implicit "-net nic"
+     * requested one
+     * (2) CONFIG_SLIRP not set, in which case the implicit "-net nic"
+     * sets up a nic that isn't connected to anything.
+     */
+    if (default_net) {
+        return;
+    }
+
+    net_hub_check_clients();
+
+    QTAILQ_FOREACH(nc, &net_clients, next) {
+        if (!nc->peer) {
+            fprintf(stderr, "Warning: %s %s has no peer\n",
+                    nc->info->type == NET_CLIENT_OPTIONS_KIND_NIC ?
+                    "nic" : "netdev", nc->name);
+        }
+    }
+
+    /* Check that all NICs requested via -net nic actually got created.
+     * NICs created via -device don't need to be checked here because
+     * they are always instantiated.
+     */
+    for (i = 0; i < MAX_NICS; i++) {
+        NICInfo *nd = &nd_table[i];
+        if (nd->used && !nd->instantiated) {
+            fprintf(stderr, "Warning: requested NIC (%s, model %s) "
+                    "was not created (not supported by this machine?)\n",
+                    nd->name ? nd->name : "anonymous",
+                    nd->model ? nd->model : "unspecified");
+        }
+    }
+}
+
+static int net_init_client(QemuOpts *opts, void *dummy)
+{
+    Error *local_err = NULL;
+
+    net_client_init(opts, 0, &local_err);
+    if (error_is_set(&local_err)) {
+        qerror_report_err(local_err);
+        error_free(local_err);
+        return -1;
+    }
+
+    return 0;
+}
+
+static int net_init_netdev(QemuOpts *opts, void *dummy)
+{
+    Error *local_err = NULL;
+    int ret;
+
+    ret = net_client_init(opts, 1, &local_err);
+    if (error_is_set(&local_err)) {
+        qerror_report_err(local_err);
+        error_free(local_err);
+        return -1;
+    }
+
+    return ret;
+}
+
+int net_init_clients(void)
+{
+    QemuOptsList *net = qemu_find_opts("net");
+
+    if (default_net) {
+        /* if no clients, we use a default config */
+        qemu_opts_set(net, NULL, "type", "nic");
+#ifdef CONFIG_SLIRP
+        qemu_opts_set(net, NULL, "type", "user");
+#endif
+    }
+
+    QTAILQ_INIT(&net_clients);
+
+    if (qemu_opts_foreach(qemu_find_opts("netdev"), net_init_netdev, NULL, 1) == -1)
+        return -1;
+
+    if (qemu_opts_foreach(net, net_init_client, NULL, 1) == -1) {
+        return -1;
+    }
+
+    return 0;
+}
+
+int net_client_parse(QemuOptsList *opts_list, const char *optarg)
+{
+#if defined(CONFIG_SLIRP)
+    int ret;
+    if (net_slirp_parse_legacy(opts_list, optarg, &ret)) {
+        return ret;
+    }
+#endif
+
+    if (!qemu_opts_parse(opts_list, optarg, 1)) {
+        return -1;
+    }
+
+    default_net = 0;
+    return 0;
+}
+
+/* From FreeBSD */
+/* XXX: optimize */
+unsigned compute_mcast_idx(const uint8_t *ep)
+{
+    uint32_t crc;
+    int carry, i, j;
+    uint8_t b;
+
+    crc = 0xffffffff;
+    for (i = 0; i < 6; i++) {
+        b = *ep++;
+        for (j = 0; j < 8; j++) {
+            carry = ((crc & 0x80000000L) ? 1 : 0) ^ (b & 0x01);
+            crc <<= 1;
+            b >>= 1;
+            if (carry) {
+                crc = ((crc ^ POLYNOMIAL) | carry);
+            }
+        }
+    }
+    return crc >> 26;
+}