trunk/src/GPGOE.c

/* GPGOE.c - GnuPG for Outlook Express
 *      Copyright (C) 2001, 2002, 2003, 2006 Timo Schulz
 *
 * This file is part of GPGOE.
 *
 * GPGOE is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation; either version 2.1 of the License, or
 * (at your option) any later version.
 * 
 * GPGOE is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with GPGOE; if not, write to the Free Software Foundation, 
 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <windows.h>
#include <stdio.h>
#include "gpgme.h"
#include "GPGOE.h"

/* Global DLL module handle. */
HINSTANCE mod_hinst_dll;

/* Outlook Express old window procedure. */
WNDPROC oe_proc_old;

/* DLL hook handle for the CBT function. */
static HHOOK ctb_hook = NULL;

/* Outlook Express window handle. */
static HWND oe_hwnd = NULL;

/* We need a shared section to define variables which
   will keep their values in all address spaces. */
#ifdef __GNUC__
#define ATTR_SEC __attribute__((section (".SHARDAT"), shared))
#else
#define ATTR_SEC
#pragma data_seg(".SHARDAT")
#endif
static int gpgoe_active_modes ATTR_SEC = 0;
#ifndef __GNUC__
#pragma data_seg()
#endif
#undef ATTR_SEC


/* Supported plug-in modes. */
enum gpgoe_mode_t {
    GPGOE_MODE_NORMAL     = 0,
    GPGOE_MODE_PLAINREPLY = 1      /* decrypt mails before a reply. */
};


/* Main DLL entry point. */
BOOL WINAPI
DllMain (HINSTANCE hinst_dll, DWORD reason, LPVOID reserved)
{
    switch (reason) {
    case DLL_PROCESS_ATTACH: 
        mod_hinst_dll = hinst_dll; 
        break;

    case DLL_PROCESS_DETACH: 
        mod_hinst_dll = NULL; 
        break;

    case DLL_THREAD_ATTACH: 
        break;

    case DLL_THREAD_DETACH: 
        break;
    }
    
    return TRUE;
}


/* Quick and dirty check if the dialog is a common dialog
   and the 'File {Open, Save}' style. */
static int 
is_common_file_dlg (HWND h)
{
    HWND button = GetDlgItem (h, 1040);
    char wclass[200];

    if (button == NULL)
        return 0;
    if (GetClassName (button, wclass, 200) > 0
        && !stricmp (wclass, "Button"))
        return -1;
    return 0;
}


/* CTB hook procedure.
   Monitors the creation of all windows and subclass the window
   if it belongs to the Outlook Express (message) class. */
static LRESULT CALLBACK 
ctb_proc (int code, WPARAM wparam, LPARAM lparam)
{
    HWND hwnd;
    char wclass[256];

    if (code < 0)
        return CallNextHookEx (ctb_hook, code, wparam, lparam);

    hwnd = (HWND)wparam;
    switch (code) {
    case HCBT_CREATEWND:
        GetClassName (hwnd, wclass, sizeof (wclass) - 1);
        if (!strcmp (wclass, "ATH_Note")) {
            oe_proc_old = (WNDPROC) GetWindowLong (hwnd, GWL_WNDPROC);
            if (!oe_proc_old)
                show_error (NULL, "GPGOE", MB_ICONERROR|MB_OK,
                            "Could not get window procedure ec=%d",
                            (int)GetLastError ());
            else if (!SetWindowLong (hwnd, GWL_WNDPROC, (LONG)(WNDPROC)oe_proc))
                show_error (NULL, "GPGOE", MB_ICONERROR|MB_OK,
                           "Could not set window procedure: ec=%d",
                           (int)GetLastError ());
            else
                oe_hwnd = hwnd;
        }

        if ((gpgoe_active_modes & GPGOE_MODE_PLAINREPLY) &&
            !strcmp (wclass, "Outlook Express Browser Class")) {
            oe_main_proc_old = (WNDPROC)GetWindowLong (hwnd, GWL_WNDPROC);
            if (!oe_main_proc_old)
                show_error (NULL, "GPGOE", MB_ICONERROR|MB_OK,
                            "Could not get window procedure ec=%d",
                            (int)GetLastError ());
            else if (!SetWindowLong (hwnd, GWL_WNDPROC, (LONG)(WNDPROC)oe_main_proc))
                show_error (NULL, "GPGOE", MB_ICONERROR|MB_OK,
                            "Could not set window procedure: ec=%d",
                            (int)GetLastError ());
        }
        break;

#if 0
    case HCBT_ACTIVATE:
        if (plugin_active != NULL && 
            WaitForSingleObject (plugin_active, 0) == WAIT_OBJECT_0) {
            char wclass[200];

            if (GetClassName (hwnd, wclass, sizeof (wclass)-1) <= 0 ||
                !strstr (wclass, "#32770") || !is_common_file_dlg (hwnd))
                break;
            of_proc_old = (WNDPROC)GetWindowLong (hwnd, GWL_WNDPROC);
            SetWindowLong (hwnd, GWL_WNDPROC, (LONG)(WNDPROC)of_proc);
        }
        break;
#endif  
    }   
    return CallNextHookEx (ctb_hook, code, wparam, lparam);
}


/* Initialize the hooks; a named mutex prevents that the
   initialisation is done twice.
   Return value: 0 on success. */
int
gpgoe_initialize (void)
{
    CreateMutex (NULL, TRUE, "gpgoe");
    if (GetLastError () == ERROR_ALREADY_EXISTS)
        return 0;
    ctb_hook = SetWindowsHookEx (WH_CBT, ctb_proc, mod_hinst_dll, 0);
    return ctb_hook? 0 : (int)GetLastError ();
}


/* Deinitialize the hooks and close all handles.
   Return value: 0 on success. */
int
gpgoe_remove (void)
{
    HANDLE hd;
    int rc;

    hd = CreateMutex (NULL, TRUE, "gpgoe");
    if (GetLastError() == ERROR_ALREADY_EXISTS) {
        oe_hwnd = NULL;
        CloseHandle (hd);
    }
    SetWindowLong (oe_hwnd, GWL_WNDPROC, (LONG)(WNDPROC)oe_proc_old);
    rc = UnhookWindowsHookEx (ctb_hook);
    return rc ? 0 : (int)GetLastError ();
}


/* Change the active plug-in modes, enable mode @mode. */
void
gpgoe_set_active_modes (int mode)
{
    gpgoe_active_modes = mode;
}


int
gpgoe_get_active_modes (void)
{
    return gpgoe_active_modes;
}

1	/* GPGOE.c - GnuPG for Outlook Express
2	* Copyright (C) 2001, 2002, 2003, 2006 Timo Schulz
3	*
4	* This file is part of GPGOE.
5	*
6	* GPGOE is free software; you can redistribute it and/or modify
7	* it under the terms of the GNU Lesser General Public License as published by
8	* the Free Software Foundation; either version 2.1 of the License, or
9	* (at your option) any later version.
10	*
11	* GPGOE is distributed in the hope that it will be useful,
12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14	* GNU General Public License for more details.
15	*
16	* You should have received a copy of the GNU Lesser General Public License
17	* along with GPGOE; if not, write to the Free Software Foundation,
18	* Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
19	*/
20
21	#ifdef HAVE_CONFIG_H
22	#include <config.h>
23	#endif
24
25	#include <windows.h>
26	#include <stdio.h>
27	#include "gpgme.h"
28	#include "GPGOE.h"
29
30	/* Global DLL module handle. */
31	HINSTANCE mod_hinst_dll;
32
33	/* Outlook Express old window procedure. */
34	WNDPROC oe_proc_old;
35
36	/* DLL hook handle for the CBT function. */
37	static HHOOK ctb_hook = NULL;
38
39	/* Outlook Express window handle. */
40	static HWND oe_hwnd = NULL;
41
42	/* We need a shared section to define variables which
43	will keep their values in all address spaces. */
44	#ifdef __GNUC__
45	#define ATTR_SEC __attribute__((section (".SHARDAT"), shared))
46	#else
47	#define ATTR_SEC
48	#pragma data_seg(".SHARDAT")
49	#endif
50	static int gpgoe_active_modes ATTR_SEC = 0;
51	#ifndef __GNUC__
52	#pragma data_seg()
53	#endif
54	#undef ATTR_SEC
55
56
57	/* Supported plug-in modes. */
58	enum gpgoe_mode_t {
59	GPGOE_MODE_NORMAL = 0,
60	GPGOE_MODE_PLAINREPLY = 1 /* decrypt mails before a reply. */
61	};
62
63
64	/* Main DLL entry point. */
65	BOOL WINAPI
66	DllMain (HINSTANCE hinst_dll, DWORD reason, LPVOID reserved)
67	{
68	switch (reason) {
69	case DLL_PROCESS_ATTACH:
70	mod_hinst_dll = hinst_dll;
71	break;
72
73	case DLL_PROCESS_DETACH:
74	mod_hinst_dll = NULL;
75	break;
76
77	case DLL_THREAD_ATTACH:
78	break;
79
80	case DLL_THREAD_DETACH:
81	break;
82	}
83
84	return TRUE;
85	}
86
87
88	/* Quick and dirty check if the dialog is a common dialog
89	and the 'File {Open, Save}' style. */
90	static int
91	is_common_file_dlg (HWND h)
92	{
93	HWND button = GetDlgItem (h, 1040);
94	char wclass[200];
95
96	if (button == NULL)
97	return 0;
98	if (GetClassName (button, wclass, 200) > 0
99	&& !stricmp (wclass, "Button"))
100	return -1;
101	return 0;
102	}
103
104
105
106	/* CTB hook procedure.
107	Monitors the creation of all windows and subclass the window
108	if it belongs to the Outlook Express (message) class. */
109	static LRESULT CALLBACK
110	ctb_proc (int code, WPARAM wparam, LPARAM lparam)
111	{
112	HWND hwnd;
113	char wclass[256];
114
115	if (code < 0)
116	return CallNextHookEx (ctb_hook, code, wparam, lparam);
117
118	hwnd = (HWND)wparam;
119	switch (code) {
120	case HCBT_CREATEWND:
121	GetClassName (hwnd, wclass, sizeof (wclass) - 1);
122	if (!strcmp (wclass, "ATH_Note")) {
123	oe_proc_old = (WNDPROC) GetWindowLong (hwnd, GWL_WNDPROC);
124	if (!oe_proc_old)
125	show_error (NULL, "GPGOE", MB_ICONERROR\|MB_OK,
126	"Could not get window procedure ec=%d",
127	(int)GetLastError ());
128	else if (!SetWindowLong (hwnd, GWL_WNDPROC, (LONG)(WNDPROC)oe_proc))
129	show_error (NULL, "GPGOE", MB_ICONERROR\|MB_OK,
130	"Could not set window procedure: ec=%d",
131	(int)GetLastError ());
132	else
133	oe_hwnd = hwnd;
134	}
135
136	if ((gpgoe_active_modes & GPGOE_MODE_PLAINREPLY) &&
137	!strcmp (wclass, "Outlook Express Browser Class")) {
138	oe_main_proc_old = (WNDPROC)GetWindowLong (hwnd, GWL_WNDPROC);
139	if (!oe_main_proc_old)
140	show_error (NULL, "GPGOE", MB_ICONERROR\|MB_OK,
141	"Could not get window procedure ec=%d",
142	(int)GetLastError ());
143	else if (!SetWindowLong (hwnd, GWL_WNDPROC, (LONG)(WNDPROC)oe_main_proc))
144	show_error (NULL, "GPGOE", MB_ICONERROR\|MB_OK,
145	"Could not set window procedure: ec=%d",
146	(int)GetLastError ());
147	}
148	break;
149
150	#if 0
151	case HCBT_ACTIVATE:
152	if (plugin_active != NULL &&
153	WaitForSingleObject (plugin_active, 0) == WAIT_OBJECT_0) {
154	char wclass[200];
155
156	if (GetClassName (hwnd, wclass, sizeof (wclass)-1) <= 0 \|\|
157	!strstr (wclass, "#32770") \|\| !is_common_file_dlg (hwnd))
158	break;
159	of_proc_old = (WNDPROC)GetWindowLong (hwnd, GWL_WNDPROC);
160	SetWindowLong (hwnd, GWL_WNDPROC, (LONG)(WNDPROC)of_proc);
161	}
162	break;
163	#endif
164	}
165	return CallNextHookEx (ctb_hook, code, wparam, lparam);
166	}
167
168
169	/* Initialize the hooks; a named mutex prevents that the
170	initialisation is done twice.
171	Return value: 0 on success. */
172	int
173	gpgoe_initialize (void)
174	{
175	CreateMutex (NULL, TRUE, "gpgoe");
176	if (GetLastError () == ERROR_ALREADY_EXISTS)
177	return 0;
178	ctb_hook = SetWindowsHookEx (WH_CBT, ctb_proc, mod_hinst_dll, 0);
179	return ctb_hook? 0 : (int)GetLastError ();
180	}
181
182
183	/* Deinitialize the hooks and close all handles.
184	Return value: 0 on success. */
185	int
186	gpgoe_remove (void)
187	{
188	HANDLE hd;
189	int rc;
190
191	hd = CreateMutex (NULL, TRUE, "gpgoe");
192	if (GetLastError() == ERROR_ALREADY_EXISTS) {
193	oe_hwnd = NULL;
194	CloseHandle (hd);
195	}
196	SetWindowLong (oe_hwnd, GWL_WNDPROC, (LONG)(WNDPROC)oe_proc_old);
197	rc = UnhookWindowsHookEx (ctb_hook);
198	return rc ? 0 : (int)GetLastError ();
199	}
200
201
202	/* Change the active plug-in modes, enable mode @mode. */
203	void
204	gpgoe_set_active_modes (int mode)
205	{
206	gpgoe_active_modes = mode;
207	}
208
209
210	int
211	gpgoe_get_active_modes (void)
212	{
213	return gpgoe_active_modes;
214	}
215