trunk/src/OEPassphraseCBDlg.c

/* OEPassphraseDLG.cpp - GPGME Passphrase Callback 
 *      Copyright (C) 2001, 2002, 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.
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <windows.h>
#include <assert.h>
#include "resource.h"
#include "gpgme.h"
#include "GPGOE.h"


/* Structure for the passphrase callback. */
struct pass_cb_s {
    const char *uid_hint;
    const char *passphrase_info;
    char keyid[8+2];
    char *pass;
    HWND main_wnd;
    int cancel;
    int prev_was_bad;
};


/* Reference to the passphrase cache. */
extern char gpgoe_pass_cache[HASH_BUCKETS][MAX_PASS_LEN];


DWORD hash_string (const char *str_param);

/* Store the passphrase @pass in the hash table using the keyid @keyid
   as the index. */
static void
passphrase_put (char ctx[HASH_BUCKETS][MAX_PASS_LEN], const char *keyid, 
                const char *pass)               
{
    int pos = hash_string (keyid) % HASH_BUCKETS;
    int n, passlen;

    /* We cannot store passphrase of that size. */
    passlen = strlen (pass);
    if (passlen > MAX_PASS_LEN-1)
        return;
    
    n = 0;
    while (n < HASH_BUCKETS) {
        if (strlen (ctx[(pos+n) % HASH_BUCKETS]) != 0) {
            n++;
            continue;
        }
        memcpy (ctx[(pos+n) % HASH_BUCKETS], keyid, strlen (keyid));
        strncpy (ctx[(pos+n) % HASH_BUCKETS]+strlen (keyid), pass, passlen);
        break;
    }
}


/* Return the requested passphrase from the hash table @ctx
   using the keyid @keyid as the index. Or NULL if there is
   no stored passphrase. */
static const char*
passphrase_get (char ctx[HASH_BUCKETS][MAX_PASS_LEN], const char *keyid)
{
    const char *item;
    int pos = hash_string (keyid) % HASH_BUCKETS;
    int n;

    n = 0;
    item = gpgoe_pass_cache[pos];
    while (n < HASH_BUCKETS) {
        item = ctx[(pos+n) % HASH_BUCKETS];
        if (!strncmp (item, keyid, strlen (keyid)))
            break;
        n++;
    }
    
    if (strlen (item) > 0 && !strncmp (item, keyid, strlen (keyid)))
        return item + strlen (keyid);
    /* Return NULL to indicate no matching entry. */
    return NULL;
}


/* Extract public key algorithm from passwd info. */
const char*
get_pubkey_algo (const char *passphrase_info)
{    
    size_t pos = 16+1+16+1;

    /* AA6F7AB7DD3B4A21 E71D9BC8C93A8529 1 0 */
    assert (strlen (passphrase_info) > pos);
    switch (atol (passphrase_info+pos)) {
    case  1: return "RSA";
    case 17: return "DSA";
    case 16: return "ELG";
    default: break;
    }
    return "???";
}


/* Passphrase callback dialog box procedure. */
BOOL CALLBACK
pass_cb_dlg_proc (HWND dlg, UINT msg, WPARAM wparam, LPARAM lparam)
{
    static pass_cb_t ctx;
    char *info;
    int n;
    
    switch (msg) {
    case WM_INITDIALOG:
        ctx = (pass_cb_t)lparam;
        assert (ctx != NULL);
        if (ctx->uid_hint && ctx->passphrase_info) {
            char *utf8_uid = utf8_to_native (ctx->uid_hint+17);
            info = xcalloc (1, strlen (utf8_uid) +  strlen (ctx->keyid) + 32);
            sprintf (info, _("%s\n%s key, ID %s"), utf8_uid, 
                     get_pubkey_algo (ctx->passphrase_info), ctx->keyid);
            SetDlgItemText (dlg, IDC_DECRYPT_MSG, info);
            free_if_alloc (utf8_uid);
            free_if_alloc (info);
        }
        SetDlgItemText (dlg, IDOK, _("&OK"));
        SetDlgItemText (dlg, IDCANCEL, _("&Cancel"));
        SetDlgItemText (dlg, IDC_DECRYPT_PWDINFO, _("Please enter your passphrase"));
        SendDlgItemMessage (dlg, IDC_DECRYPT_PWD, EM_SETPASSWORDCHAR, 
                            (WPARAM)(UINT)'*', 0);
        CheckDlgButton (dlg, IDC_DECRYPT_HIDE, BST_CHECKED);
        SetDlgItemText (dlg, IDC_DECRYPT_HIDE, _("&Hide typing"));
        SetWindowText (dlg, _("Decryption"));
        SetForegroundWindow (dlg);
        center_window (dlg, ctx->main_wnd);
        break;

    case WM_COMMAND:
        if (HIWORD (wparam) == BN_CLICKED &&
            LOWORD (wparam) == IDC_DECRYPT_HIDE) {
            HWND hwnd;
            hwnd = GetDlgItem (dlg, IDC_DECRYPT_PWD);
            SendMessage (hwnd, EM_SETPASSWORDCHAR, 
                         IsDlgButtonChecked (dlg, IDC_DECRYPT_HIDE)? '*' : 0, 0);
            SetFocus (hwnd);
            break;
        }

        switch (LOWORD (wparam)) {
        case IDCANCEL:
            ctx->cancel = 1;
            free_if_alloc (ctx->pass);
            EndDialog (dlg, FALSE);
            break;

        case IDOK:
            if (ctx->prev_was_bad)
                SetDlgItemText (dlg, IDC_DECRYPT_PWDINFO,
                                _("Invalid passphrase; please enter your passphrase again"));
            else
                SetDlgItemText (dlg, IDC_DECRYPT_PWDINFO,
                                _("Please enter your passphrase"));
            n = SendDlgItemMessage (dlg, IDC_DECRYPT_PWD,
                                    WM_GETTEXTLENGTH, 0, 0);
            if (n < 1) {
                MessageBox (dlg, _("Please enter your passphrase"),
                            _("GPG Plug-in Info"), MB_ICONINFORMATION|MB_OK);
                return FALSE;
            }
            /* Make sure we reset the cancel flag. */
            ctx->cancel = 0;
            ctx->pass = xcalloc (1, n+2);
            GetDlgItemText (dlg, IDC_DECRYPT_PWD, ctx->pass, n+1);

            if (gpgoe_get_active_modes () & GPGOE_MODE_CACHEPASS)
                passphrase_put (gpgoe_pass_cache, ctx->keyid, ctx->pass);
            EndDialog (dlg, TRUE);
            break;
        }
        break;
    }
    return FALSE;
}


/* GPGME compatible passphrase callback. */
gpgme_error_t
passphrase_cb (void *hook,
               const char *uid_hint,
               const char *passphrase_info,
               int prev_was_bad, int fd)
{
    pass_cb_t cb = (pass_cb_t)hook;
    HANDLE fp = (HANDLE)fd;
    const char *pass;
    DWORD nwritten;
    
    assert (cb != NULL);
    cb->prev_was_bad = prev_was_bad;
    if (prev_was_bad && !cb->cancel) {
        wipememory (cb->pass, strlen (cb->pass));
        free_if_alloc (cb->pass);
    }
    if (!cb->pass && !cb->cancel) {
        cb->uid_hint = uid_hint;
        cb->passphrase_info = passphrase_info;
        memset (cb->keyid, 0, sizeof (cb->keyid));
        memcpy (cb->keyid, cb->passphrase_info+8, 8);

        pass = passphrase_get (gpgoe_pass_cache, cb->keyid);
        if (pass)
            cb->pass = xstrdup (pass);
        else
            DialogBoxParam (mod_hinst_dll, (LPCTSTR)IDD_DECRYPT,
                            cb->main_wnd, pass_cb_dlg_proc, (LPARAM)cb);
    }
    if (cb->cancel)
        WriteFile (fp, "\n", 1, &nwritten, NULL);
    else if (cb->pass != NULL) {
        WriteFile (fp, cb->pass, strlen (cb->pass), &nwritten, NULL);
        WriteFile (fp, "\n", 1, &nwritten, NULL);
    }
    return 0;
}


/* Allocate new passphrase callback context. */
pass_cb_t
new_pass_cb (HWND main)
{
    pass_cb_t cb_val;

    cb_val = xcalloc (1, sizeof *cb_val);
    cb_val->main_wnd = main;
    return cb_val;
}


/* Free passphrase callback context. */
void
free_pass_cb (pass_cb_t cb)
{
    if (!cb)
        return;
    if (cb->pass) {
        wipememory (cb->pass, strlen (cb->pass));
        free_if_alloc (cb->pass);
    }
    free_if_alloc (cb);
}


/* Return 1 if the passphrase dialog were cancelled. */
int
pass_cb_cancelled (pass_cb_t cb)
{
    return cb->cancel;
}


/* Reset the passphrase cache by overwritting each items with zeroes */
void
reset_pass_cache (void)
{
    int i;

    for (i=0; i < HASH_BUCKETS; i++)
        wipememory (gpgoe_pass_cache[i], DIM (gpgoe_pass_cache[i]));
}
1	/* OEPassphraseDLG.cpp - GPGME Passphrase Callback
2	* Copyright (C) 2001, 2002, 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
17	#ifdef HAVE_CONFIG_H
18	#include <config.h>
19	#endif
20	#include <windows.h>
21	#include <assert.h>
22	#include "resource.h"
23	#include "gpgme.h"
24	#include "GPGOE.h"
25
26
27	/* Structure for the passphrase callback. */
28	struct pass_cb_s {
29	const char *uid_hint;
30	const char *passphrase_info;
31	char keyid[8+2];
32	char *pass;
33	HWND main_wnd;
34	int cancel;
35	int prev_was_bad;
36	};
37
38
39	/* Reference to the passphrase cache. */
40	extern char gpgoe_pass_cache[HASH_BUCKETS][MAX_PASS_LEN];
41
42
43	DWORD hash_string (const char *str_param);
44
45	/* Store the passphrase @pass in the hash table using the keyid @keyid
46	as the index. */
47	static void
48	passphrase_put (char ctx[HASH_BUCKETS][MAX_PASS_LEN], const char *keyid,
49	const char *pass)
50	{
51	int pos = hash_string (keyid) % HASH_BUCKETS;
52	int n, passlen;
53
54	/* We cannot store passphrase of that size. */
55	passlen = strlen (pass);
56	if (passlen > MAX_PASS_LEN-1)
57	return;
58
59	n = 0;
60	while (n < HASH_BUCKETS) {
61	if (strlen (ctx[(pos+n) % HASH_BUCKETS]) != 0) {
62	n++;
63	continue;
64	}
65	memcpy (ctx[(pos+n) % HASH_BUCKETS], keyid, strlen (keyid));
66	strncpy (ctx[(pos+n) % HASH_BUCKETS]+strlen (keyid), pass, passlen);
67	break;
68	}
69	}
70
71
72	/* Return the requested passphrase from the hash table @ctx
73	using the keyid @keyid as the index. Or NULL if there is
74	no stored passphrase. */
75	static const char*
76	passphrase_get (char ctx[HASH_BUCKETS][MAX_PASS_LEN], const char *keyid)
77	{
78	const char *item;
79	int pos = hash_string (keyid) % HASH_BUCKETS;
80	int n;
81
82	n = 0;
83	item = gpgoe_pass_cache[pos];
84	while (n < HASH_BUCKETS) {
85	item = ctx[(pos+n) % HASH_BUCKETS];
86	if (!strncmp (item, keyid, strlen (keyid)))
87	break;
88	n++;
89	}
90
91	if (strlen (item) > 0 && !strncmp (item, keyid, strlen (keyid)))
92	return item + strlen (keyid);
93	/* Return NULL to indicate no matching entry. */
94	return NULL;
95	}
96
97
98	/* Extract public key algorithm from passwd info. */
99	const char*
100	get_pubkey_algo (const char *passphrase_info)
101	{
102	size_t pos = 16+1+16+1;
103
104	/* AA6F7AB7DD3B4A21 E71D9BC8C93A8529 1 0 */
105	assert (strlen (passphrase_info) > pos);
106	switch (atol (passphrase_info+pos)) {
107	case 1: return "RSA";
108	case 17: return "DSA";
109	case 16: return "ELG";
110	default: break;
111	}
112	return "???";
113	}
114
115
116	/* Passphrase callback dialog box procedure. */
117	BOOL CALLBACK
118	pass_cb_dlg_proc (HWND dlg, UINT msg, WPARAM wparam, LPARAM lparam)
119	{
120	static pass_cb_t ctx;
121	char *info;
122	int n;
123
124	switch (msg) {
125	case WM_INITDIALOG:
126	ctx = (pass_cb_t)lparam;
127	assert (ctx != NULL);
128	if (ctx->uid_hint && ctx->passphrase_info) {
129	char *utf8_uid = utf8_to_native (ctx->uid_hint+17);
130	info = xcalloc (1, strlen (utf8_uid) + strlen (ctx->keyid) + 32);
131	sprintf (info, _("%s\n%s key, ID %s"), utf8_uid,
132	get_pubkey_algo (ctx->passphrase_info), ctx->keyid);
133	SetDlgItemText (dlg, IDC_DECRYPT_MSG, info);
134	free_if_alloc (utf8_uid);
135	free_if_alloc (info);
136	}
137	SetDlgItemText (dlg, IDOK, _("&OK"));
138	SetDlgItemText (dlg, IDCANCEL, _("&Cancel"));
139	SetDlgItemText (dlg, IDC_DECRYPT_PWDINFO, _("Please enter your passphrase"));
140	SendDlgItemMessage (dlg, IDC_DECRYPT_PWD, EM_SETPASSWORDCHAR,
141	(WPARAM)(UINT)'*', 0);
142	CheckDlgButton (dlg, IDC_DECRYPT_HIDE, BST_CHECKED);
143	SetDlgItemText (dlg, IDC_DECRYPT_HIDE, _("&Hide typing"));
144	SetWindowText (dlg, _("Decryption"));
145	SetForegroundWindow (dlg);
146	center_window (dlg, ctx->main_wnd);
147	break;
148
149	case WM_COMMAND:
150	if (HIWORD (wparam) == BN_CLICKED &&
151	LOWORD (wparam) == IDC_DECRYPT_HIDE) {
152	HWND hwnd;
153	hwnd = GetDlgItem (dlg, IDC_DECRYPT_PWD);
154	SendMessage (hwnd, EM_SETPASSWORDCHAR,
155	IsDlgButtonChecked (dlg, IDC_DECRYPT_HIDE)? '*' : 0, 0);
156	SetFocus (hwnd);
157	break;
158	}
159
160	switch (LOWORD (wparam)) {
161	case IDCANCEL:
162	ctx->cancel = 1;
163	free_if_alloc (ctx->pass);
164	EndDialog (dlg, FALSE);
165	break;
166
167	case IDOK:
168	if (ctx->prev_was_bad)
169	SetDlgItemText (dlg, IDC_DECRYPT_PWDINFO,
170	_("Invalid passphrase; please enter your passphrase again"));
171	else
172	SetDlgItemText (dlg, IDC_DECRYPT_PWDINFO,
173	_("Please enter your passphrase"));
174	n = SendDlgItemMessage (dlg, IDC_DECRYPT_PWD,
175	WM_GETTEXTLENGTH, 0, 0);
176	if (n < 1) {
177	MessageBox (dlg, _("Please enter your passphrase"),
178	_("GPG Plug-in Info"), MB_ICONINFORMATION\|MB_OK);
179	return FALSE;
180	}
181	/* Make sure we reset the cancel flag. */
182	ctx->cancel = 0;
183	ctx->pass = xcalloc (1, n+2);
184	GetDlgItemText (dlg, IDC_DECRYPT_PWD, ctx->pass, n+1);
185
186	if (gpgoe_get_active_modes () & GPGOE_MODE_CACHEPASS)
187	passphrase_put (gpgoe_pass_cache, ctx->keyid, ctx->pass);
188	EndDialog (dlg, TRUE);
189	break;
190	}
191	break;
192	}
193	return FALSE;
194	}
195
196
197	/* GPGME compatible passphrase callback. */
198	gpgme_error_t
199	passphrase_cb (void *hook,
200	const char *uid_hint,
201	const char *passphrase_info,
202	int prev_was_bad, int fd)
203	{
204	pass_cb_t cb = (pass_cb_t)hook;
205	HANDLE fp = (HANDLE)fd;
206	const char *pass;
207	DWORD nwritten;
208
209	assert (cb != NULL);
210	cb->prev_was_bad = prev_was_bad;
211	if (prev_was_bad && !cb->cancel) {
212	wipememory (cb->pass, strlen (cb->pass));
213	free_if_alloc (cb->pass);
214	}
215	if (!cb->pass && !cb->cancel) {
216	cb->uid_hint = uid_hint;
217	cb->passphrase_info = passphrase_info;
218	memset (cb->keyid, 0, sizeof (cb->keyid));
219	memcpy (cb->keyid, cb->passphrase_info+8, 8);
220
221	pass = passphrase_get (gpgoe_pass_cache, cb->keyid);
222	if (pass)
223	cb->pass = xstrdup (pass);
224	else
225	DialogBoxParam (mod_hinst_dll, (LPCTSTR)IDD_DECRYPT,
226	cb->main_wnd, pass_cb_dlg_proc, (LPARAM)cb);
227	}
228	if (cb->cancel)
229	WriteFile (fp, "\n", 1, &nwritten, NULL);
230	else if (cb->pass != NULL) {
231	WriteFile (fp, cb->pass, strlen (cb->pass), &nwritten, NULL);
232	WriteFile (fp, "\n", 1, &nwritten, NULL);
233	}
234	return 0;
235	}
236
237
238	/* Allocate new passphrase callback context. */
239	pass_cb_t
240	new_pass_cb (HWND main)
241	{
242	pass_cb_t cb_val;
243
244	cb_val = xcalloc (1, sizeof *cb_val);
245	cb_val->main_wnd = main;
246	return cb_val;
247	}
248
249
250
251	/* Free passphrase callback context. */
252	void
253	free_pass_cb (pass_cb_t cb)
254	{
255	if (!cb)
256	return;
257	if (cb->pass) {
258	wipememory (cb->pass, strlen (cb->pass));
259	free_if_alloc (cb->pass);
260	}
261	free_if_alloc (cb);
262	}
263
264
265	/* Return 1 if the passphrase dialog were cancelled. */
266	int
267	pass_cb_cancelled (pass_cb_t cb)
268	{
269	return cb->cancel;
270	}
271
272
273	/* Reset the passphrase cache by overwritting each items with zeroes */
274	void
275	reset_pass_cache (void)
276	{
277	int i;
278
279	for (i=0; i < HASH_BUCKETS; i++)
280	wipememory (gpgoe_pass_cache[i], DIM (gpgoe_pass_cache[i]));
281	}