ctrl_iface_named_pipe.c

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/*
 * WPA Supplicant / Windows Named Pipe -based control interface
 * Copyright (c) 2004-2006, Jouni Malinen <j@w1.fi>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Alternatively, this software may be distributed under the terms of BSD
 * license.
 *
 * See README and COPYING for more details.
 */

#include "includes.h"

#include "common.h"
#include "eloop.h"
#include "config.h"
#include "eapol_supp/eapol_supp_sm.h"
#include "wpa_supplicant_i.h"
#include "ctrl_iface.h"
#include "common/wpa_ctrl.h"

#ifdef __MINGW32_VERSION
/* mingw-w32api v3.1 does not yet include sddl.h, so define needed parts here
 */
#define SDDL_REVISION_1 1
BOOL WINAPI ConvertStringSecurityDescriptorToSecurityDescriptorA(
        LPCSTR, DWORD, PSECURITY_DESCRIPTOR *, PULONG);
BOOL WINAPI ConvertStringSecurityDescriptorToSecurityDescriptorW(
        LPCWSTR, DWORD, PSECURITY_DESCRIPTOR *, PULONG);
#ifdef UNICODE
#define ConvertStringSecurityDescriptorToSecurityDescriptor \
ConvertStringSecurityDescriptorToSecurityDescriptorW
#else
#define ConvertStringSecurityDescriptorToSecurityDescriptor \
ConvertStringSecurityDescriptorToSecurityDescriptorA
#endif
#else /* __MINGW32_VERSION */
#ifndef _WIN32_WINNT
#define _WIN32_WINNT 0x0500
#endif
#include <sddl.h>
#endif /* __MINGW32_VERSION */

#ifndef WPA_SUPPLICANT_NAMED_PIPE
#define WPA_SUPPLICANT_NAMED_PIPE "WpaSupplicant"
#endif
#define NAMED_PIPE_PREFIX TEXT("\\\\.\\pipe\\") TEXT(WPA_SUPPLICANT_NAMED_PIPE)

/* Per-interface ctrl_iface */

#define REQUEST_BUFSIZE 256
#define REPLY_BUFSIZE 4096

struct ctrl_iface_priv;

struct wpa_ctrl_dst {
        /* Note: OVERLAPPED must be the first member of struct wpa_ctrl_dst */
        OVERLAPPED overlap;
        struct wpa_ctrl_dst *next, *prev;
        struct ctrl_iface_priv *priv;
        HANDLE pipe;
        int attached;
        int debug_level;
        int errors;
        char req_buf[REQUEST_BUFSIZE];
        char *rsp_buf;
        int used;
};


struct ctrl_iface_priv {
        struct wpa_supplicant *wpa_s;
        struct wpa_ctrl_dst *ctrl_dst;
        SECURITY_ATTRIBUTES attr;
        int sec_attr_set;
};


static void wpa_supplicant_ctrl_iface_send(struct ctrl_iface_priv *priv,
                                           int level, const char *buf,
                                           size_t len);

static void ctrl_close_pipe(struct wpa_ctrl_dst *dst);
static void wpa_supplicant_ctrl_iface_receive(void *, void *);
static VOID WINAPI ctrl_iface_read_completed(DWORD err, DWORD bytes,
                                             LPOVERLAPPED overlap);

struct wpa_global_dst;
static void global_close_pipe(struct wpa_global_dst *dst);
static void wpa_supplicant_global_iface_receive(void *eloop_data,
                                                void *user_ctx);
static VOID WINAPI global_iface_read_completed(DWORD err, DWORD bytes,
                                               LPOVERLAPPED overlap);


static int ctrl_broken_pipe(HANDLE pipe, int used)
{
        DWORD err;

        if (PeekNamedPipe(pipe, NULL, 0, NULL, NULL, NULL))
                return 0;

        err = GetLastError();
        if (err == ERROR_BROKEN_PIPE || (err == ERROR_BAD_PIPE && used))
                return 1;
        return 0;
}


static void ctrl_flush_broken_pipes(struct ctrl_iface_priv *priv)
{
        struct wpa_ctrl_dst *dst, *next;

        dst = priv->ctrl_dst;

        while (dst) {
                next = dst->next;
                if (ctrl_broken_pipe(dst->pipe, dst->used)) {
                        wpa_printf(MSG_DEBUG, "CTRL: closing broken pipe %p",
                                   dst);
                        ctrl_close_pipe(dst);
                }
                dst = next;
        }
}


static int ctrl_open_pipe(struct ctrl_iface_priv *priv)
{
        struct wpa_ctrl_dst *dst;
        DWORD err;
        TCHAR name[256];

        dst = os_zalloc(sizeof(*dst));
        if (dst == NULL)
                return -1;
        wpa_printf(MSG_DEBUG, "CTRL: Open pipe %p", dst);

        dst->priv = priv;
        dst->debug_level = MSG_INFO;
        dst->pipe = INVALID_HANDLE_VALUE;

        dst->overlap.hEvent = CreateEvent(NULL, TRUE, TRUE, NULL);
        if (dst->overlap.hEvent == NULL) {
                wpa_printf(MSG_ERROR, "CTRL: CreateEvent failed: %d",
                           (int) GetLastError());
                goto fail;
        }

        eloop_register_event(dst->overlap.hEvent,
                             sizeof(dst->overlap.hEvent),
                             wpa_supplicant_ctrl_iface_receive, dst, NULL);

#ifdef UNICODE
        _snwprintf(name, 256, NAMED_PIPE_PREFIX TEXT("-%S"),
                   priv->wpa_s->ifname);
#else /* UNICODE */
        os_snprintf(name, 256, NAMED_PIPE_PREFIX "-%s",
                    priv->wpa_s->ifname);
#endif /* UNICODE */

        /* TODO: add support for configuring access list for the pipe */
        dst->pipe = CreateNamedPipe(name,
                                    PIPE_ACCESS_DUPLEX | FILE_FLAG_OVERLAPPED,
                                    PIPE_TYPE_MESSAGE |
                                    PIPE_READMODE_MESSAGE |
                                    PIPE_WAIT,
                                    15, REPLY_BUFSIZE, REQUEST_BUFSIZE,
                                    1000,
                                    priv->sec_attr_set ? &priv->attr : NULL);
        if (dst->pipe == INVALID_HANDLE_VALUE) {
                wpa_printf(MSG_ERROR, "CTRL: CreateNamedPipe failed: %d",
                           (int) GetLastError());
                goto fail;
        }

        if (ConnectNamedPipe(dst->pipe, &dst->overlap)) {
                wpa_printf(MSG_ERROR, "CTRL: ConnectNamedPipe failed: %d",
                           (int) GetLastError());
                CloseHandle(dst->pipe);
                os_free(dst);
                return -1;
        }

        err = GetLastError();
        switch (err) {
        case ERROR_IO_PENDING:
                wpa_printf(MSG_DEBUG, "CTRL: ConnectNamedPipe: connection in "
                           "progress");
                break;
        case ERROR_PIPE_CONNECTED:
                wpa_printf(MSG_DEBUG, "CTRL: ConnectNamedPipe: already "
                           "connected");
                if (SetEvent(dst->overlap.hEvent))
                        break;
                /* fall through */
        default:
                wpa_printf(MSG_DEBUG, "CTRL: ConnectNamedPipe error: %d",
                           (int) err);
                CloseHandle(dst->pipe);
                os_free(dst);
                return -1;
        }

        dst->next = priv->ctrl_dst;
        if (dst->next)
                dst->next->prev = dst;
        priv->ctrl_dst = dst;

        return 0;

fail:
        ctrl_close_pipe(dst);
        return -1;
}


static void ctrl_close_pipe(struct wpa_ctrl_dst *dst)
{
        wpa_printf(MSG_DEBUG, "CTRL: close pipe %p", dst);

        if (dst->overlap.hEvent) {
                eloop_unregister_event(dst->overlap.hEvent,
                                       sizeof(dst->overlap.hEvent));
                CloseHandle(dst->overlap.hEvent);
        }

        if (dst->pipe != INVALID_HANDLE_VALUE) {
                /*
                 * Could use FlushFileBuffers() here to guarantee that all data
                 * gets delivered to the client, but that can block, so let's
                 * not do this for now.
                 * FlushFileBuffers(dst->pipe);
                 */
                CloseHandle(dst->pipe);
        }

        if (dst->prev)
                dst->prev->next = dst->next;
        else
                dst->priv->ctrl_dst = dst->next;
        if (dst->next)
                dst->next->prev = dst->prev;

        os_free(dst->rsp_buf);
        os_free(dst);
}


static VOID WINAPI ctrl_iface_write_completed(DWORD err, DWORD bytes,
                                              LPOVERLAPPED overlap)
{
        struct wpa_ctrl_dst *dst = (struct wpa_ctrl_dst *) overlap;
        wpa_printf(MSG_DEBUG, "CTRL: Overlapped write completed: dst=%p "
                   "err=%d bytes=%d", dst, (int) err, (int) bytes);
        if (err) {
                ctrl_close_pipe(dst);
                return;
        }

        os_free(dst->rsp_buf);
        dst->rsp_buf = NULL;

        if (!ReadFileEx(dst->pipe, dst->req_buf, sizeof(dst->req_buf),
                        &dst->overlap, ctrl_iface_read_completed)) {
                wpa_printf(MSG_DEBUG, "CTRL: ReadFileEx failed: %d",
                           (int) GetLastError());
                ctrl_close_pipe(dst);
                return;
        }
        wpa_printf(MSG_DEBUG, "CTRL: Overlapped read started for %p", dst);
}


static void wpa_supplicant_ctrl_iface_rx(struct wpa_ctrl_dst *dst, size_t len)
{
        struct wpa_supplicant *wpa_s = dst->priv->wpa_s;
        char *reply = NULL, *send_buf;
        size_t reply_len = 0, send_len;
        int new_attached = 0;
        char *buf = dst->req_buf;

        dst->used = 1;
        if (len >= REQUEST_BUFSIZE)
                len = REQUEST_BUFSIZE - 1;
        buf[len] = '\0';

        if (os_strcmp(buf, "ATTACH") == 0) {
                dst->attached = 1;
                wpa_printf(MSG_DEBUG, "CTRL_IFACE monitor attached");
                new_attached = 1;
                reply_len = 2;
        } else if (os_strcmp(buf, "DETACH") == 0) {
                dst->attached = 0;
                wpa_printf(MSG_DEBUG, "CTRL_IFACE monitor detached");
                reply_len = 2;
        } else if (os_strncmp(buf, "LEVEL ", 6) == 0) {
                wpa_printf(MSG_DEBUG, "CTRL_IFACE LEVEL %s", buf + 6);
                dst->debug_level = atoi(buf + 6);
                reply_len = 2;
        } else {
                reply = wpa_supplicant_ctrl_iface_process(wpa_s, buf,
                                                          &reply_len);
        }

        if (reply) {
                send_buf = reply;
                send_len = reply_len;
        } else if (reply_len == 2) {
                send_buf = "OK\n";
                send_len = 3;
        } else {
                send_buf = "FAIL\n";
                send_len = 5;
        }

        os_free(dst->rsp_buf);
        dst->rsp_buf = os_malloc(send_len);
        if (dst->rsp_buf == NULL) {
                ctrl_close_pipe(dst);
                os_free(reply);
                return;
        }
        os_memcpy(dst->rsp_buf, send_buf, send_len);
        os_free(reply);

        if (!WriteFileEx(dst->pipe, dst->rsp_buf, send_len, &dst->overlap,
                         ctrl_iface_write_completed)) {
                wpa_printf(MSG_DEBUG, "CTRL: WriteFileEx failed: %d",
                           (int) GetLastError());
                ctrl_close_pipe(dst);
        } else {
                wpa_printf(MSG_DEBUG, "CTRL: Overlapped write started for %p",
                           dst);
        }

        if (new_attached)
                eapol_sm_notify_ctrl_attached(wpa_s->eapol);
}


static VOID WINAPI ctrl_iface_read_completed(DWORD err, DWORD bytes,
                                             LPOVERLAPPED overlap)
{
        struct wpa_ctrl_dst *dst = (struct wpa_ctrl_dst *) overlap;
        wpa_printf(MSG_DEBUG, "CTRL: Overlapped read completed: dst=%p err=%d "
                   "bytes=%d", dst, (int) err, (int) bytes);
        if (err == 0 && bytes > 0)
                wpa_supplicant_ctrl_iface_rx(dst, bytes);
}


static void wpa_supplicant_ctrl_iface_receive(void *eloop_data, void *user_ctx)
{
        struct wpa_ctrl_dst *dst = eloop_data;
        struct ctrl_iface_priv *priv = dst->priv;
        DWORD bytes;

        wpa_printf(MSG_DEBUG, "CTRL: wpa_supplicant_ctrl_iface_receive");
        ResetEvent(dst->overlap.hEvent);

        if (!GetOverlappedResult(dst->pipe, &dst->overlap, &bytes, FALSE)) {
                wpa_printf(MSG_DEBUG, "CTRL: GetOverlappedResult failed: %d",
                           (int) GetLastError());
                return;
        }
        wpa_printf(MSG_DEBUG, "CTRL: GetOverlappedResult: New client "
                   "connected");

        /* Open a new named pipe for the next client. */
        ctrl_open_pipe(priv);

        /* Use write completion function to start reading a command */
        ctrl_iface_write_completed(0, 0, &dst->overlap);

        ctrl_flush_broken_pipes(priv);
}


static int ctrl_iface_parse(struct ctrl_iface_priv *priv, const char *params)
{
        const char *sddl = NULL;
        TCHAR *t_sddl;

        if (os_strncmp(params, "SDDL=", 5) == 0)
                sddl = params + 5;
        if (!sddl) {
                sddl = os_strstr(params, " SDDL=");
                if (sddl)
                        sddl += 6;
        }

        if (!sddl)
                return 0;

        wpa_printf(MSG_DEBUG, "CTRL: SDDL='%s'", sddl);
        os_memset(&priv->attr, 0, sizeof(priv->attr));
        priv->attr.nLength = sizeof(priv->attr);
        priv->attr.bInheritHandle = FALSE;
        t_sddl = wpa_strdup_tchar(sddl);
        if (t_sddl == NULL)
                return -1;
        if (!ConvertStringSecurityDescriptorToSecurityDescriptor(
                    t_sddl, SDDL_REVISION_1,
                    (PSECURITY_DESCRIPTOR *) (void *)
                    &priv->attr.lpSecurityDescriptor,
                    NULL)) {
                os_free(t_sddl);
                wpa_printf(MSG_ERROR, "CTRL: SDDL='%s' - could not convert to "
                           "security descriptor: %d",
                           sddl, (int) GetLastError());
                return -1;
        }
        os_free(t_sddl);

        priv->sec_attr_set = 1;

        return 0;
}


static void wpa_supplicant_ctrl_iface_msg_cb(void *ctx, int level,
                                             const char *txt, size_t len)
{
        struct wpa_supplicant *wpa_s = ctx;
        if (wpa_s == NULL || wpa_s->ctrl_iface == NULL)
                return;
        wpa_supplicant_ctrl_iface_send(wpa_s->ctrl_iface, level, txt, len);
}


struct ctrl_iface_priv *
wpa_supplicant_ctrl_iface_init(struct wpa_supplicant *wpa_s)
{
        struct ctrl_iface_priv *priv;

        priv = os_zalloc(sizeof(*priv));
        if (priv == NULL)
                return NULL;
        priv->wpa_s = wpa_s;

        if (wpa_s->conf->ctrl_interface == NULL)
                return priv;

        if (ctrl_iface_parse(priv, wpa_s->conf->ctrl_interface) < 0) {
                os_free(priv);
                return NULL;
        }

        if (ctrl_open_pipe(priv) < 0) {
                os_free(priv);
                return NULL;
        }

        wpa_msg_register_cb(wpa_supplicant_ctrl_iface_msg_cb);

        return priv;
}


void wpa_supplicant_ctrl_iface_deinit(struct ctrl_iface_priv *priv)
{
        while (priv->ctrl_dst)
                ctrl_close_pipe(priv->ctrl_dst);
        if (priv->sec_attr_set)
                LocalFree(priv->attr.lpSecurityDescriptor);
        os_free(priv);
}


static void wpa_supplicant_ctrl_iface_send(struct ctrl_iface_priv *priv,
                                           int level, const char *buf,
                                           size_t len)
{
        struct wpa_ctrl_dst *dst, *next;
        char levelstr[10];
        int idx;
        char *sbuf;
        int llen;
        DWORD written;

        dst = priv->ctrl_dst;
        if (dst == NULL)
                return;

        os_snprintf(levelstr, sizeof(levelstr), "<%d>", level);

        llen = os_strlen(levelstr);
        sbuf = os_malloc(llen + len);
        if (sbuf == NULL)
                return;

        os_memcpy(sbuf, levelstr, llen);
        os_memcpy(sbuf + llen, buf, len);

        idx = 0;
        while (dst) {
                next = dst->next;
                if (dst->attached && level >= dst->debug_level) {
                        wpa_printf(MSG_DEBUG, "CTRL_IFACE monitor send %p",
                                   dst);
                        if (!WriteFile(dst->pipe, sbuf, llen + len, &written,
                                       NULL)) {
                                wpa_printf(MSG_DEBUG, "CTRL: WriteFile to dst "
                                           "%p failed: %d",
                                           dst, (int) GetLastError());
                                dst->errors++;
                                if (dst->errors > 10)
                                        ctrl_close_pipe(dst);
                        } else
                                dst->errors = 0;
                }
                idx++;
                dst = next;
        }
        os_free(sbuf);
}


void wpa_supplicant_ctrl_iface_wait(struct ctrl_iface_priv *priv)
{
        wpa_printf(MSG_DEBUG, "CTRL_IFACE - %s - wait for monitor",
                   priv->wpa_s->ifname);
        if (priv->ctrl_dst == NULL)
                return;
        WaitForSingleObject(priv->ctrl_dst->pipe, INFINITE);
}


/* Global ctrl_iface */

struct ctrl_iface_global_priv;

struct wpa_global_dst {
        /* Note: OVERLAPPED must be the first member of struct wpa_global_dst
         */
        OVERLAPPED overlap;
        struct wpa_global_dst *next, *prev;
        struct ctrl_iface_global_priv *priv;
        HANDLE pipe;
        char req_buf[REQUEST_BUFSIZE];
        char *rsp_buf;
        int used;
};

struct ctrl_iface_global_priv {
        struct wpa_global *global;
        struct wpa_global_dst *ctrl_dst;
};


static void global_flush_broken_pipes(struct ctrl_iface_global_priv *priv)
{
        struct wpa_global_dst *dst, *next;

        dst = priv->ctrl_dst;

        while (dst) {
                next = dst->next;
                if (ctrl_broken_pipe(dst->pipe, dst->used)) {
                        wpa_printf(MSG_DEBUG, "CTRL: closing broken pipe %p",
                                   dst);
                        global_close_pipe(dst);
                }
                dst = next;
        }
}


static int global_open_pipe(struct ctrl_iface_global_priv *priv)
{
        struct wpa_global_dst *dst;
        DWORD err;

        dst = os_zalloc(sizeof(*dst));
        if (dst == NULL)
                return -1;
        wpa_printf(MSG_DEBUG, "CTRL: Open pipe %p", dst);

        dst->priv = priv;
        dst->pipe = INVALID_HANDLE_VALUE;

        dst->overlap.hEvent = CreateEvent(NULL, TRUE, TRUE, NULL);
        if (dst->overlap.hEvent == NULL) {
                wpa_printf(MSG_ERROR, "CTRL: CreateEvent failed: %d",
                           (int) GetLastError());
                goto fail;
        }

        eloop_register_event(dst->overlap.hEvent,
                             sizeof(dst->overlap.hEvent),
                             wpa_supplicant_global_iface_receive, dst, NULL);

        /* TODO: add support for configuring access list for the pipe */
        dst->pipe = CreateNamedPipe(NAMED_PIPE_PREFIX,
                                    PIPE_ACCESS_DUPLEX | FILE_FLAG_OVERLAPPED,
                                    PIPE_TYPE_MESSAGE |
                                    PIPE_READMODE_MESSAGE |
                                    PIPE_WAIT,
                                    10, REPLY_BUFSIZE, REQUEST_BUFSIZE,
                                    1000, NULL);
        if (dst->pipe == INVALID_HANDLE_VALUE) {
                wpa_printf(MSG_ERROR, "CTRL: CreateNamedPipe failed: %d",
                           (int) GetLastError());
                goto fail;
        }

        if (ConnectNamedPipe(dst->pipe, &dst->overlap)) {
                wpa_printf(MSG_ERROR, "CTRL: ConnectNamedPipe failed: %d",
                           (int) GetLastError());
                CloseHandle(dst->pipe);
                os_free(dst);
                return -1;
        }

        err = GetLastError();
        switch (err) {
        case ERROR_IO_PENDING:
                wpa_printf(MSG_DEBUG, "CTRL: ConnectNamedPipe: connection in "
                           "progress");
                break;
        case ERROR_PIPE_CONNECTED:
                wpa_printf(MSG_DEBUG, "CTRL: ConnectNamedPipe: already "
                           "connected");
                if (SetEvent(dst->overlap.hEvent))
                        break;
                /* fall through */
        default:
                wpa_printf(MSG_DEBUG, "CTRL: ConnectNamedPipe error: %d",
                           (int) err);
                CloseHandle(dst->pipe);
                os_free(dst);
                return -1;
        }

        dst->next = priv->ctrl_dst;
        if (dst->next)
                dst->next->prev = dst;
        priv->ctrl_dst = dst;

        return 0;

fail:
        global_close_pipe(dst);
        return -1;
}


static void global_close_pipe(struct wpa_global_dst *dst)
{
        wpa_printf(MSG_DEBUG, "CTRL: close pipe %p", dst);

        if (dst->overlap.hEvent) {
                eloop_unregister_event(dst->overlap.hEvent,
                                       sizeof(dst->overlap.hEvent));
                CloseHandle(dst->overlap.hEvent);
        }

        if (dst->pipe != INVALID_HANDLE_VALUE) {
                /*
                 * Could use FlushFileBuffers() here to guarantee that all data
                 * gets delivered to the client, but that can block, so let's
                 * not do this for now.
                 * FlushFileBuffers(dst->pipe);
                 */
                CloseHandle(dst->pipe);
        }

        if (dst->prev)
                dst->prev->next = dst->next;
        else
                dst->priv->ctrl_dst = dst->next;
        if (dst->next)
                dst->next->prev = dst->prev;

        os_free(dst->rsp_buf);
        os_free(dst);
}


static VOID WINAPI global_iface_write_completed(DWORD err, DWORD bytes,
                                                LPOVERLAPPED overlap)
{
        struct wpa_global_dst *dst = (struct wpa_global_dst *) overlap;
        wpa_printf(MSG_DEBUG, "CTRL: Overlapped write completed: dst=%p "
                   "err=%d bytes=%d", dst, (int) err, (int) bytes);
        if (err) {
                global_close_pipe(dst);
                return;
        }

        os_free(dst->rsp_buf);
        dst->rsp_buf = NULL;

        if (!ReadFileEx(dst->pipe, dst->req_buf, sizeof(dst->req_buf),
                        &dst->overlap, global_iface_read_completed)) {
                wpa_printf(MSG_DEBUG, "CTRL: ReadFileEx failed: %d",
                           (int) GetLastError());
                global_close_pipe(dst);
                /* FIX: if this was the pipe waiting for new global
                 * connections, at this point there are no open global pipes..
                 * Should try to open a new pipe.. */
                return;
        }
        wpa_printf(MSG_DEBUG, "CTRL: Overlapped read started for %p", dst);
}


static void wpa_supplicant_global_iface_rx(struct wpa_global_dst *dst,
                                           size_t len)
{
        struct wpa_global *global = dst->priv->global;
        char *reply = NULL, *send_buf;
        size_t reply_len = 0, send_len;
        char *buf = dst->req_buf;

        dst->used = 1;
        if (len >= REQUEST_BUFSIZE)
                len = REQUEST_BUFSIZE - 1;
        buf[len] = '\0';

        reply = wpa_supplicant_global_ctrl_iface_process(global, buf,
                                                         &reply_len);
        if (reply) {
                send_buf = reply;
                send_len = reply_len;
        } else if (reply_len) {
                send_buf = "FAIL\n";
                send_len = 5;
        } else {
                os_free(dst->rsp_buf);
                dst->rsp_buf = NULL;
                return;
        }

        os_free(dst->rsp_buf);
        dst->rsp_buf = os_malloc(send_len);
        if (dst->rsp_buf == NULL) {
                global_close_pipe(dst);
                os_free(reply);
                return;
        }
        os_memcpy(dst->rsp_buf, send_buf, send_len);
        os_free(reply);

        if (!WriteFileEx(dst->pipe, dst->rsp_buf, send_len, &dst->overlap,
                         global_iface_write_completed)) {
                wpa_printf(MSG_DEBUG, "CTRL: WriteFileEx failed: %d",
                           (int) GetLastError());
                global_close_pipe(dst);
        } else {
                wpa_printf(MSG_DEBUG, "CTRL: Overlapped write started for %p",
                           dst);
        }
}


static VOID WINAPI global_iface_read_completed(DWORD err, DWORD bytes,
                                               LPOVERLAPPED overlap)
{
        struct wpa_global_dst *dst = (struct wpa_global_dst *) overlap;
        wpa_printf(MSG_DEBUG, "CTRL: Overlapped read completed: dst=%p err=%d "
                   "bytes=%d", dst, (int) err, (int) bytes);
        if (err == 0 && bytes > 0)
                wpa_supplicant_global_iface_rx(dst, bytes);
}


static void wpa_supplicant_global_iface_receive(void *eloop_data,
                                                void *user_ctx)
{
        struct wpa_global_dst *dst = eloop_data;
        struct ctrl_iface_global_priv *priv = dst->priv;
        DWORD bytes;

        wpa_printf(MSG_DEBUG, "CTRL: wpa_supplicant_global_iface_receive");
        ResetEvent(dst->overlap.hEvent);

        if (!GetOverlappedResult(dst->pipe, &dst->overlap, &bytes, FALSE)) {
                wpa_printf(MSG_DEBUG, "CTRL: GetOverlappedResult failed: %d",
                           (int) GetLastError());
                return;
        }
        wpa_printf(MSG_DEBUG, "CTRL: GetOverlappedResult: New client "
                   "connected");

        /* Open a new named pipe for the next client. */
        if (global_open_pipe(priv) < 0) {
                wpa_printf(MSG_DEBUG, "CTRL: global_open_pipe failed");
                return;
        }

        /* Use write completion function to start reading a command */
        global_iface_write_completed(0, 0, &dst->overlap);

        global_flush_broken_pipes(priv);
}


struct ctrl_iface_global_priv *
wpa_supplicant_global_ctrl_iface_init(struct wpa_global *global)
{
        struct ctrl_iface_global_priv *priv;

        priv = os_zalloc(sizeof(*priv));
        if (priv == NULL)
                return NULL;
        priv->global = global;

        if (global_open_pipe(priv) < 0) {
                os_free(priv);
                return NULL;
        }

        return priv;
}


void
wpa_supplicant_global_ctrl_iface_deinit(struct ctrl_iface_global_priv *priv)
{
        while (priv->ctrl_dst)
                global_close_pipe(priv->ctrl_dst);
        os_free(priv);
}