trunk/Src/wptPassphraseCB.cpp

/* wptPassphraseCB.cpp - GPGME Passphrase Callback
 *      Copyright (C) 2001, 2002, 2003, 2005 Timo Schulz
 *      Copyright (C) 2005 g10 Code GmbH
 *
 * This file is part of WinPT.
 *
 * WinPT is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License 
 * as published by the Free Software Foundation; either version 2 
 * of the License, or (at your option) any later version.
 *  
 * WinPT 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 General Public License 
 * along with WinPT; if not, write to the Free Software Foundation, 
 * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 
 */

#include <windows.h>
#include <ctype.h>

#include "../resource.h"
#include "wptNLS.h"
#include "wptW32API.h"
#include "wptVersion.h"
#include "wptGPG.h"
#include "wptCommonCtl.h"
#include "wptContext.h"
#include "wptDlgs.h"
#include "wptUTF8.h"
#include "wptErrors.h"
#include "wptTypes.h"
#include "wptKeyList.h"
#include "wptAgent.h"
#include "wptRegistry.h"

const char* get_symkey_algo (int algo);

#define item_ctrl_id( cmd ) \
    ((cmd) == GPG_CMD_DECRYPT? IDC_DECRYPT_PWD : IDC_DECRYPT_SIGN_PWD)

#define item_ctrl_id2(cmd) \
    ((cmd) == GPG_CMD_DECRYPT? IDC_DECRYPT_HIDE : IDC_DECRYPT_SIGN_HIDE)


/* Overwrite passphrase and free memory. */
static void
burn_passphrase (char **pwd)
{
    char *pass = *pwd;  
    memset (pass, 0, strlen (pass));
    delete []pass;
    *pwd = NULL;
}


/* Dialog procedure for the passphrase callback. */
static BOOL CALLBACK
passphrase_callback_proc (HWND dlg, UINT msg, WPARAM wparam, LPARAM lparam)
{    
    static passphrase_cb_s * c;
    gpgme_decrypt_result_t res;
    gpgme_sign_result_t res_sig;
    gpgme_key_t key;
    void *ctx = NULL, *item;
    const char *id;
    char *info;
    int n;

    switch (msg) {
    case WM_INITDIALOG:
        c = (passphrase_cb_s *)lparam;
        if (!c)
            BUG (0);
        SetWindowText (dlg, c->title);
        if (c->gpg_cmd == GPG_CMD_DECRYPT) {
            SetDlgItemText( dlg, IDC_DECRYPT_LISTINF,
                _("Encrypted with the following public key(s)") );
            CheckDlgButton( dlg, IDC_DECRYPT_HIDE, BST_CHECKED );
        }
        else if (c->gpg_cmd == GPG_CMD_SIGN)
            CheckDlgButton (dlg, IDC_DECRYPT_SIGN_HIDE, BST_CHECKED);
        res = gpgme_op_decrypt_result (c->gpg);
        if (res != NULL && c->gpg_cmd == GPG_CMD_DECRYPT) {
            gpgme_recipient_t r;

            /* XXX: not all ENCRYPT_TO entries are listed here. */
            for (r = res->recipients; r; r = r->next) {
                get_pubkey (r->keyid, &key);
                if (key) {
                    char *uid;
                    id = key->uids->name;
                    if (!id)
                        id = _("Invalid User ID");
                    uid = utf8_to_wincp (id, strlen (id));
                    info = new char [32+strlen (uid)+1 + 4 + strlen (r->keyid)+1
                                     + strlen (key->uids->email)+1];
                    if (!info)
                        BUG (NULL);
                    sprintf (info, "%s <%s> (%s, 0x%s)", uid, key->uids->email,
                             get_key_pubalgo (r->pubkey_algo), r->keyid+8);
                    free (uid);
                    
                }
                else {
                    info = new char [32 + strlen (r->keyid)+1 + 4];
                    if (!info)
                        BUG (NULL);
                    sprintf (info, _("Unknown key ID (%s, 0x%s)"), 
                             get_key_pubalgo (r->pubkey_algo), r->keyid+8);
                }
                listbox_add_string (GetDlgItem (dlg, IDC_DECRYPT_LIST), info);
                free_if_alloc (info);
            }
        }
        else if (c->gpg_cmd == GPG_CMD_DECRYPT)
            EnableWindow (GetDlgItem (dlg, IDC_DECRYPT_LIST), FALSE);
        SetDlgItemText (dlg, c->gpg_cmd == GPG_CMD_DECRYPT?
                        IDC_DECRYPT_PWDINFO : IDC_DECRYPT_SIGN_PWDINFO,
                        c->bad_pwd? _("Bad passphrase; Enter passphrase again") :
                        _("Please enter your passphrase"));
        if (c->gpg_cmd == GPG_CMD_DECRYPT) {
            SetFocus (GetDlgItem (dlg, IDC_DECRYPT_PWD));
            if (res && !res->recipients) {
                const char *s = _("Symmetric encryption.\n"
                                  "%s encrypted data.");
                const char *alg = get_symkey_algo (c->sym.sym_algo);
                info = new char[strlen (s) + strlen (alg) + 2];
                if (!info)
                    BUG (NULL);
                sprintf (info, s, alg);
                SetDlgItemText (dlg, IDC_DECRYPT_MSG, info);
                free_if_alloc (info);
            }
            else
                SetDlgItemText (dlg, IDC_DECRYPT_MSG, c->info);
        }
        else {
            SetFocus( GetDlgItem (dlg, IDC_DECRYPT_SIGN_PWD));
            SetDlgItemText (dlg, IDC_DECRYPT_SIGN_MSG, c->info);
        }
        center_window (dlg, NULL);
        SetForegroundWindow (dlg);
        set_active_window (dlg);
        return FALSE;

        case WM_SYSCOMMAND:
            if (LOWORD (wparam) == SC_CLOSE) {
                SetDlgItemText (dlg, item_ctrl_id( c->gpg_cmd ), "");
                c->cancel = 1;
                EndDialog (dlg, TRUE);
            }
            break;

        case WM_COMMAND:
            switch( HIWORD( wparam ) ) {
            case BN_CLICKED:
                if ( LOWORD( wparam ) == IDC_DECRYPT_HIDE
                    || LOWORD( wparam ) == IDC_DECRYPT_SIGN_HIDE ) {
                    HWND hwnd;
                    int hide = IsDlgButtonChecked (dlg, item_ctrl_id2 (c->gpg_cmd));
                    hwnd = GetDlgItem (dlg, item_ctrl_id (c->gpg_cmd));
                    SendMessage (hwnd, EM_SETPASSWORDCHAR, hide? '*' : 0, 0);
                    SetFocus (hwnd);
                }
            }

            switch (LOWORD (wparam)) {
            case IDOK:  
                /* fixme: the item is even cached when the passphrase is not
                          correct, which means that the user needs to delete all
                          cached entries to continue. */
                if (c->pwd)
                    burn_passphrase (&c->pwd);
                n = item_get_text_length (dlg, item_ctrl_id (c->gpg_cmd));
                if (!n) {
                    c->pwd = new char[2];
                    if (!c->pwd)
                        BUG (NULL);
                    strcpy (c->pwd, "");
                }
                else {
                    c->pwd = new char[n+2];
                    if (!c->pwd)
                        BUG (NULL);
                    GetDlgItemText (dlg, item_ctrl_id (c->gpg_cmd), c->pwd, n+1);
                }
                res = gpgme_op_decrypt_result (c->gpg);
                if (!res)
                    res_sig = gpgme_op_sign_result (c->gpg);
                if (reg_prefs.cache_time > 0 && !c->is_card && 
                    ((res && res->recipients) || (res_sig && res_sig->signatures))) {
                    if (agent_get_cache (c->keyid, &item))
                        agent_unlock_cache_entry (&item);
                    else
                        agent_put_cache (c->keyid, c->pwd, reg_prefs.cache_time);
                }
                EndDialog (dlg, TRUE);
                return TRUE;
                
            case IDCANCEL:
                SetDlgItemText (dlg, item_ctrl_id (c->gpg_cmd), "" );
                c->cancel = 1;
                EndDialog (dlg, FALSE);
                return FALSE;
            }
            break;
    }
    
    return FALSE;
}


/* Extract the main keyid from @pass_info.
   Return value: long main keyid or NULL for an error. */
static const char*
parse_gpg_keyid (const char *pass_info)
{
    static char keyid[16+1];
    
    /* XXX: check for leading alpha-chars? */
    if (strlen (pass_info) < 16)
        return NULL;
    /* the format of the desc buffer looks like this:
       request_keyid[16] main_keyid[16] keytype[1] keylength[4]
       we use the main keyid to use only one cache entry. */
    strncpy (keyid, pass_info+17, 16);
    keyid[16] = 0;
    return keyid;
}


/* Parse the information in @uid_hint and @pass_info to generate
   a input message for the user in @desc. */
static int
parse_gpg_description (const char *uid_hint, const char *pass_info,
                       char *desc, int size)
{
    gpgme_pubkey_algo_t algo;
    char usedkey[16+1], mainkey[16+1];
    char *uid, *p;
    int n=0;

    if (strlen (uid_hint) < 17) {
        *desc = 0;
        return -1;
    }

    while (p = strsep ((char**)&pass_info, " ")) {
        switch (n++) {
        case 0: strncpy (mainkey, p, 16); mainkey[16] = 0; break;
        case 1: strncpy (usedkey, p, 16); usedkey[16] = 0; break;
        case 2: algo = (gpgme_pubkey_algo_t)atol (p); break;
        }
    }
    uid_hint += 16; /* skip keyid */
    uid_hint += 1;  /* space */

    uid = utf8_to_wincp (uid_hint, strlen (uid_hint));

    if (strcmp (usedkey, mainkey))
        _snprintf (desc, size-1, 
                   _("You need a passphrase to unlock the secret key for\n"
                     "user: \"%s\"\n"
                     "%s key, ID %s (main key ID %s)\n"),
                   uid, get_key_pubalgo (algo), usedkey+8, mainkey+8);
    else if (!strcmp (usedkey, mainkey))
        _snprintf (desc, size-1,
                   _("You need a passphrase to unlock the secret key for\n"
                     "user: \"%s\"\n"
                     "%s key, ID %s\n"),
                     uid, get_key_pubalgo (algo), usedkey+8);
    free (uid);
    return 0;
}


/*
static int inline
is_hexstring (const char * p)
{
    size_t i;

    for (i=0; i < strlen (p); i++) {
        if (!isxdigit (p[i]))
            return -1;
    }
    return 0;
}
*/

/* Passphrase callback with the ability to support caching. */
gpgme_error_t
passphrase_cb (void *hook, const char *uid_hint,
               const char *passphrase_info,
               int prev_was_bad, int fd)
{
    passphrase_cb_s *c = (passphrase_cb_s*)hook;
    HANDLE hd = (HANDLE)fd;
    void *item;
    const char *keyid, *pass;
    DWORD n;
    int rc;

    if (!c)
        return gpg_error (GPG_ERR_INV_ARG);
    c->bad_pwd = prev_was_bad? 1 : 0;
    if (prev_was_bad && !c->cancel) {
        if (c->pwd)
            burn_passphrase (&c->pwd);
        agent_del_cache (c->keyid);
        c->pwd_init = 1;
    }

    if (passphrase_info) {
        if (strlen (passphrase_info) < 16 && 
            !strstr (passphrase_info, "OPENPGP")) {/* assume symetric encryption. */
            int n=2;
            c->sym.sym_algo = atoi (passphrase_info);
            if (c->sym.sym_algo > 9)
                n++;
            /* XXX: be more strict. */
            c->sym.s2k_mode = atoi (passphrase_info+n);
            c->sym.s2k_hash = atoi (passphrase_info+n+2);
        }

        keyid = parse_gpg_keyid (passphrase_info);
        pass = agent_get_cache (keyid+8, &item);
        if (pass) {
            agent_unlock_cache_entry (&item);
            c->pwd_init = 0;
            if (!WriteFile (hd, pass, strlen (pass), &n, NULL))
                log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
            if (!WriteFile (hd, "\n", 1, &n, NULL))
                log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
            return 0;
        }
    }

    if (c->pwd_init) {
        if (keyid && strlen (keyid) == 16)
            strcpy (c->keyid, keyid+8);

        /* if @passphrase_info contains 'OPENPGP' we assume a smart card
            has been used. */
        if (strstr (passphrase_info, "OPENPGP")) {
            char buf[16];
            memset (buf, 0, sizeof buf);
            strncpy (buf, "??", 2); /* XXX: fixme we need the serial no. */
            _snprintf (c->info, sizeof c->info-1,
                       _("Please enter the PIN to unlock your secret card key\n"
                         "Card: %s"), buf);
            c->is_card = 1;
        }
        else if (uid_hint)
            parse_gpg_description (uid_hint, passphrase_info, 
                                   c->info, sizeof c->info - 1);
        if (c->gpg_cmd == GPG_CMD_DECRYPT) {
            rc = DialogBoxParam (glob_hinst, (LPCSTR)IDD_WINPT_DECRYPT,
                                 (HWND)c->hwnd, passphrase_callback_proc,
                                 (LPARAM)c);
        }
        else if (c->gpg_cmd == GPG_CMD_SIGN) {
            rc = DialogBoxParam (glob_hinst, (LPCSTR)IDD_WINPT_DECRYPT_SIGN,
                                 (HWND)c->hwnd, passphrase_callback_proc,
                                 (LPARAM)c);
        }
        if (rc == -1) {
            WriteFile (hd, "\n", 1, &n, NULL);
            return 0;
        }
        c->pwd_init = 0;
    }
    if (c->cancel) {
        WriteFile (hd, "\n", 1, &n, NULL);
        return 0;
    }

    WriteFile (hd, c->pwd, strlen (c->pwd), &n, NULL);
    WriteFile (hd, "\n", 1, &n, NULL);
    return 0;
}


/* Initialize the given passphrase callback @cb with the
   used gpgme context @ctx, the command @cmd and a title
   @title for the dialog. */
void
set_gpg_passphrase_cb (passphrase_cb_s *cb, gpgme_ctx_t ctx, 
                       int cmd, HWND hwnd, const char *title)
{
    memset (cb, 0, sizeof *cb);
    cb->gpg_cmd = cmd;
    cb->bad_pwd = 0;
    cb->is_card = 0;
    cb->cancel = 0;
    cb->hwnd = hwnd;
    cb->pwd_init = 1;
    free_if_alloc (cb->title);
    cb->title = m_strdup (title);
    if (!cb->title)
        BUG (NULL);
    gpgme_set_passphrase_cb (ctx, passphrase_cb, cb);
    cb->gpg = ctx;
}


/* Release a passphrase callback @ctx. */
void
release_gpg_passphrase_cb (passphrase_cb_s *ctx)
{
    if (!ctx)
        return;
    sfree_if_alloc (ctx->pwd);
    free_if_alloc (ctx->title);
}


/* Simple check to measure passphrase (@pass) quality.
   Return value: 0 on success. */
int
check_passwd_quality (const char *pass, int strict)
{
    int i, nd=0, nc=0, n;

    n = strlen (pass);
    if (n < 8)
        return -1;

    for (i=0; i < n; i++) {
        if (isdigit (pass[i])) nd++;
        if (isalpha (pass[i])) nc++;
    }

    if (nd == n || nc == n)
        return -1;

    return 0;
}
1	twoaday	2	/* wptPassphraseCB.cpp - GPGME Passphrase Callback
2	twoaday	23	* Copyright (C) 2001, 2002, 2003, 2005 Timo Schulz
3	twoaday	24	* Copyright (C) 2005 g10 Code GmbH
4	twoaday	2	*
5			* This file is part of WinPT.
6			*
7			* WinPT is free software; you can redistribute it and/or
8			* modify it under the terms of the GNU General Public License
9			* as published by the Free Software Foundation; either version 2
10			* of the License, or (at your option) any later version.
11			*
12			* WinPT is distributed in the hope that it will be useful,
13			* but WITHOUT ANY WARRANTY; without even the implied warranty of
14			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15			* General Public License for more details.
16			*
17			* You should have received a copy of the GNU General Public License
18			* along with WinPT; if not, write to the Free Software Foundation,
19			* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20			*/
21
22			#include <windows.h>
23			#include <ctype.h>
24
25			#include "../resource.h"
26			#include "wptNLS.h"
27			#include "wptW32API.h"
28			#include "wptVersion.h"
29			#include "wptGPG.h"
30			#include "wptCommonCtl.h"
31			#include "wptContext.h"
32			#include "wptDlgs.h"
33			#include "wptUTF8.h"
34			#include "wptErrors.h"
35			#include "wptTypes.h"
36	twoaday	23	#include "wptKeyList.h"
37	twoaday	2	#include "wptAgent.h"
38			#include "wptRegistry.h"
39
40	twoaday	25	const char* get_symkey_algo (int algo);
41	twoaday	2
42			#define item_ctrl_id( cmd ) \
43			((cmd) == GPG_CMD_DECRYPT? IDC_DECRYPT_PWD : IDC_DECRYPT_SIGN_PWD)
44
45	twoaday	22	#define item_ctrl_id2(cmd) \
46			((cmd) == GPG_CMD_DECRYPT? IDC_DECRYPT_HIDE : IDC_DECRYPT_SIGN_HIDE)
47	twoaday	2
48	twoaday	22
49	twoaday	26	/* Overwrite passphrase and free memory. */
50			static void
51			burn_passphrase (char **pwd)
52			{
53			char pass = pwd;
54			memset (pass, 0, strlen (pass));
55			delete []pass;
56			*pwd = NULL;
57			}
58
59
60	twoaday	23	/* Dialog procedure for the passphrase callback. */
61			static BOOL CALLBACK
62	twoaday	4	passphrase_callback_proc (HWND dlg, UINT msg, WPARAM wparam, LPARAM lparam)
63	twoaday	2	{
64			static passphrase_cb_s * c;
65	twoaday	24	gpgme_decrypt_result_t res;
66			gpgme_sign_result_t res_sig;
67	twoaday	2	gpgme_key_t key;
68	twoaday	25	void ctx = NULL, item;
69	twoaday	23	const char *id;
70			char *info;
71			int n;
72	twoaday	2
73	twoaday	24	switch (msg) {
74	twoaday	2	case WM_INITDIALOG:
75			c = (passphrase_cb_s *)lparam;
76	twoaday	4	if (!c)
77			BUG (0);
78			SetWindowText (dlg, c->title);
79			if (c->gpg_cmd == GPG_CMD_DECRYPT) {
80	twoaday	2	SetDlgItemText( dlg, IDC_DECRYPT_LISTINF,
81			_("Encrypted with the following public key(s)") );
82			CheckDlgButton( dlg, IDC_DECRYPT_HIDE, BST_CHECKED );
83			}
84	twoaday	25	else if (c->gpg_cmd == GPG_CMD_SIGN)
85	twoaday	23	CheckDlgButton (dlg, IDC_DECRYPT_SIGN_HIDE, BST_CHECKED);
86	twoaday	24	res = gpgme_op_decrypt_result (c->gpg);
87			if (res != NULL && c->gpg_cmd == GPG_CMD_DECRYPT) {
88	twoaday	23	gpgme_recipient_t r;
89
90	twoaday	25	/* XXX: not all ENCRYPT_TO entries are listed here. */
91	twoaday	23	for (r = res->recipients; r; r = r->next) {
92			get_pubkey (r->keyid, &key);
93			if (key) {
94			char *uid;
95	twoaday	24	id = key->uids->name;
96	twoaday	23	if (!id)
97	twoaday	2	id = _("Invalid User ID");
98	twoaday	23	uid = utf8_to_wincp (id, strlen (id));
99	twoaday	25	info = new char [32+strlen (uid)+1 + 4 + strlen (r->keyid)+1
100			+ strlen (key->uids->email)+1];
101	twoaday	23	if (!info)
102			BUG (NULL);
103	twoaday	24	sprintf (info, "%s <%s> (%s, 0x%s)", uid, key->uids->email,
104	twoaday	23	get_key_pubalgo (r->pubkey_algo), r->keyid+8);
105			free (uid);
106	twoaday	24
107	twoaday	2	}
108	twoaday	23	else {
109	twoaday	25	info = new char [32 + strlen (r->keyid)+1 + 4];
110	twoaday	23	if (!info)
111			BUG (NULL);
112	twoaday	25	sprintf (info, _("Unknown key ID (%s, 0x%s)"),
113			get_key_pubalgo (r->pubkey_algo), r->keyid+8);
114	twoaday	23	}
115	twoaday	24	listbox_add_string (GetDlgItem (dlg, IDC_DECRYPT_LIST), info);
116	twoaday	25	free_if_alloc (info);
117	twoaday	2	}
118			}
119	twoaday	24	else if (c->gpg_cmd == GPG_CMD_DECRYPT)
120			EnableWindow (GetDlgItem (dlg, IDC_DECRYPT_LIST), FALSE);
121	twoaday	25	SetDlgItemText (dlg, c->gpg_cmd == GPG_CMD_DECRYPT?
122	twoaday	2	IDC_DECRYPT_PWDINFO : IDC_DECRYPT_SIGN_PWDINFO,
123	twoaday	26	c->bad_pwd? _("Bad passphrase; Enter passphrase again") :
124	twoaday	25	_("Please enter your passphrase"));
125	twoaday	24	if (c->gpg_cmd == GPG_CMD_DECRYPT) {
126			SetFocus (GetDlgItem (dlg, IDC_DECRYPT_PWD));
127	twoaday	25	if (res && !res->recipients) {
128			const char *s = _("Symmetric encryption.\n"
129			"%s encrypted data.");
130			const char *alg = get_symkey_algo (c->sym.sym_algo);
131			info = new char[strlen (s) + strlen (alg) + 2];
132			if (!info)
133			BUG (NULL);
134			sprintf (info, s, alg);
135			SetDlgItemText (dlg, IDC_DECRYPT_MSG, info);
136			free_if_alloc (info);
137			}
138	twoaday	24	else
139			SetDlgItemText (dlg, IDC_DECRYPT_MSG, c->info);
140	twoaday	2	}
141			else {
142	twoaday	24	SetFocus( GetDlgItem (dlg, IDC_DECRYPT_SIGN_PWD));
143			SetDlgItemText (dlg, IDC_DECRYPT_SIGN_MSG, c->info);
144	twoaday	2	}
145	twoaday	24	center_window (dlg, NULL);
146			SetForegroundWindow (dlg);
147			set_active_window (dlg);
148	twoaday	2	return FALSE;
149
150			case WM_SYSCOMMAND:
151	twoaday	26	if (LOWORD (wparam) == SC_CLOSE) {
152			SetDlgItemText (dlg, item_ctrl_id( c->gpg_cmd ), "");
153	twoaday	2	c->cancel = 1;
154	twoaday	26	EndDialog (dlg, TRUE);
155	twoaday	2	}
156	twoaday	24	break;
157	twoaday	2
158			case WM_COMMAND:
159			switch( HIWORD( wparam ) ) {
160			case BN_CLICKED:
161			if ( LOWORD( wparam ) == IDC_DECRYPT_HIDE
162			\|\| LOWORD( wparam ) == IDC_DECRYPT_SIGN_HIDE ) {
163			HWND hwnd;
164	twoaday	22	int hide = IsDlgButtonChecked (dlg, item_ctrl_id2 (c->gpg_cmd));
165			hwnd = GetDlgItem (dlg, item_ctrl_id (c->gpg_cmd));
166	twoaday	25	SendMessage (hwnd, EM_SETPASSWORDCHAR, hide? '*' : 0, 0);
167	twoaday	22	SetFocus (hwnd);
168	twoaday	2	}
169			}
170
171	twoaday	4	switch (LOWORD (wparam)) {
172			case IDOK:
173	twoaday	2	/* fixme: the item is even cached when the passphrase is not
174			correct, which means that the user needs to delete all
175			cached entries to continue. */
176	twoaday	26	if (c->pwd)
177			burn_passphrase (&c->pwd);
178	twoaday	23	n = item_get_text_length (dlg, item_ctrl_id (c->gpg_cmd));
179			if (!n) {
180			c->pwd = new char[2];
181	twoaday	26	if (!c->pwd)
182			BUG (NULL);
183	twoaday	23	strcpy (c->pwd, "");
184			}
185			else {
186	twoaday	24	c->pwd = new char[n+2];
187	twoaday	23	if (!c->pwd)
188			BUG (NULL);
189	twoaday	24	GetDlgItemText (dlg, item_ctrl_id (c->gpg_cmd), c->pwd, n+1);
190	twoaday	23	}
191	twoaday	24	res = gpgme_op_decrypt_result (c->gpg);
192			if (!res)
193			res_sig = gpgme_op_sign_result (c->gpg);
194			if (reg_prefs.cache_time > 0 && !c->is_card &&
195			((res && res->recipients) \|\| (res_sig && res_sig->signatures))) {
196	twoaday	4	if (agent_get_cache (c->keyid, &item))
197			agent_unlock_cache_entry (&item);
198	twoaday	2	else
199	twoaday	4	agent_put_cache (c->keyid, c->pwd, reg_prefs.cache_time);
200	twoaday	2	}
201	twoaday	4	EndDialog (dlg, TRUE);
202	twoaday	2	return TRUE;
203
204			case IDCANCEL:
205	twoaday	4	SetDlgItemText (dlg, item_ctrl_id (c->gpg_cmd), "" );
206	twoaday	2	c->cancel = 1;
207	twoaday	4	EndDialog (dlg, FALSE);
208	twoaday	2	return FALSE;
209			}
210			break;
211			}
212
213			return FALSE;
214	twoaday	23	}
215	twoaday	2
216
217	twoaday	23	/* Extract the main keyid from @pass_info.
218			Return value: long main keyid or NULL for an error. */
219			static const char*
220			parse_gpg_keyid (const char *pass_info)
221	twoaday	2	{
222			static char keyid[16+1];
223
224	twoaday	26	/* XXX: check for leading alpha-chars? */
225	twoaday	23	if (strlen (pass_info) < 16)
226	twoaday	2	return NULL;
227			/* the format of the desc buffer looks like this:
228			request_keyid[16] main_keyid[16] keytype[1] keylength[4]
229			we use the main keyid to use only one cache entry. */
230	twoaday	23	strncpy (keyid, pass_info+17, 16);
231			keyid[16] = 0;
232	twoaday	2	return keyid;
233	twoaday	23	}
234	twoaday	2
235
236	twoaday	23	/* Parse the information in @uid_hint and @pass_info to generate
237			a input message for the user in @desc. */
238	twoaday	26	static int
239	twoaday	23	parse_gpg_description (const char uid_hint, const char pass_info,
240			char *desc, int size)
241	twoaday	2	{
242	twoaday	23	gpgme_pubkey_algo_t algo;
243			char usedkey[16+1], mainkey[16+1];
244			char uid, p;
245			int n=0;
246	twoaday	2
247	twoaday	26	if (strlen (uid_hint) < 17) {
248			*desc = 0;
249			return -1;
250			}
251
252	twoaday	23	while (p = strsep ((char**)&pass_info, " ")) {
253			switch (n++) {
254			case 0: strncpy (mainkey, p, 16); mainkey[16] = 0; break;
255			case 1: strncpy (usedkey, p, 16); usedkey[16] = 0; break;
256			case 2: algo = (gpgme_pubkey_algo_t)atol (p); break;
257	twoaday	2	}
258			}
259	twoaday	23	uid_hint += 16; /* skip keyid */
260			uid_hint += 1; /* space */
261	twoaday	2
262	twoaday	23	uid = utf8_to_wincp (uid_hint, strlen (uid_hint));
263	twoaday	2
264	twoaday	23	if (strcmp (usedkey, mainkey))
265			_snprintf (desc, size-1,
266	twoaday	2	_("You need a passphrase to unlock the secret key for\n"
267			"user: \"%s\"\n"
268			"%s key, ID %s (main key ID %s)\n"),
269	twoaday	23	uid, get_key_pubalgo (algo), usedkey+8, mainkey+8);
270			else if (!strcmp (usedkey, mainkey))
271			_snprintf (desc, size-1,
272	twoaday	2	_("You need a passphrase to unlock the secret key for\n"
273			"user: \"%s\"\n"
274			"%s key, ID %s\n"),
275	twoaday	23	uid, get_key_pubalgo (algo), usedkey+8);
276			free (uid);
277	twoaday	26	return 0;
278	twoaday	23	}
279	twoaday	2
280
281	twoaday	26	/*
282	twoaday	2	static int inline
283	twoaday	23	is_hexstring (const char * p)
284	twoaday	2	{
285			size_t i;
286	twoaday	23
287			for (i=0; i < strlen (p); i++) {
288			if (!isxdigit (p[i]))
289	twoaday	2	return -1;
290			}
291			return 0;
292			}
293	twoaday	26	*/
294	twoaday	2
295	twoaday	23	/* Passphrase callback with the ability to support caching. */
296			gpgme_error_t
297			passphrase_cb (void hook, const char uid_hint,
298			const char *passphrase_info,
299			int prev_was_bad, int fd)
300			{
301			passphrase_cb_s c = (passphrase_cb_s)hook;
302	twoaday	24	HANDLE hd = (HANDLE)fd;
303	twoaday	23	void *item;
304			const char keyid, pass;
305	twoaday	24	DWORD n;
306	twoaday	23	int rc;
307	twoaday	2
308	twoaday	23	if (!c)
309			return gpg_error (GPG_ERR_INV_ARG);
310	twoaday	26	c->bad_pwd = prev_was_bad? 1 : 0;
311			if (prev_was_bad && !c->cancel) {
312			if (c->pwd)
313			burn_passphrase (&c->pwd);
314			agent_del_cache (c->keyid);
315			c->pwd_init = 1;
316			}
317	twoaday	2
318	twoaday	23	if (passphrase_info) {
319	twoaday	26	if (strlen (passphrase_info) < 16 &&
320			!strstr (passphrase_info, "OPENPGP")) {/* assume symetric encryption. */
321	twoaday	25	int n=2;
322			c->sym.sym_algo = atoi (passphrase_info);
323			if (c->sym.sym_algo > 9)
324			n++;
325			/* XXX: be more strict. */
326			c->sym.s2k_mode = atoi (passphrase_info+n);
327			c->sym.s2k_hash = atoi (passphrase_info+n+2);
328			}
329
330	twoaday	23	keyid = parse_gpg_keyid (passphrase_info);
331	twoaday	24	pass = agent_get_cache (keyid+8, &item);
332	twoaday	23	if (pass) {
333			agent_unlock_cache_entry (&item);
334	twoaday	2	c->pwd_init = 0;
335	twoaday	24	if (!WriteFile (hd, pass, strlen (pass), &n, NULL))
336			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
337			if (!WriteFile (hd, "\n", 1, &n, NULL))
338			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
339	twoaday	23	return 0;
340	twoaday	2	}
341			}
342
343	twoaday	23	if (c->pwd_init) {
344			if (keyid && strlen (keyid) == 16)
345			strcpy (c->keyid, keyid+8);
346
347	twoaday	26	/* if @passphrase_info contains 'OPENPGP' we assume a smart card
348			has been used. */
349			if (strstr (passphrase_info, "OPENPGP")) {
350	twoaday	2	char buf[16];
351	twoaday	23	memset (buf, 0, sizeof buf);
352	twoaday	26	strncpy (buf, "??", 2); /* XXX: fixme we need the serial no. */
353	twoaday	23	_snprintf (c->info, sizeof c->info-1,
354			_("Please enter the PIN to unlock your secret card key\n"
355			"Card: %s"), buf);
356	twoaday	2	c->is_card = 1;
357			}
358	twoaday	23	else if (uid_hint)
359			parse_gpg_description (uid_hint, passphrase_info,
360			c->info, sizeof c->info - 1);
361			if (c->gpg_cmd == GPG_CMD_DECRYPT) {
362			rc = DialogBoxParam (glob_hinst, (LPCSTR)IDD_WINPT_DECRYPT,
363			(HWND)c->hwnd, passphrase_callback_proc,
364			(LPARAM)c);
365	twoaday	2	}
366	twoaday	23	else if (c->gpg_cmd == GPG_CMD_SIGN) {
367			rc = DialogBoxParam (glob_hinst, (LPCSTR)IDD_WINPT_DECRYPT_SIGN,
368			(HWND)c->hwnd, passphrase_callback_proc,
369			(LPARAM)c);
370	twoaday	2	}
371	twoaday	23	if (rc == -1) {
372	twoaday	24	WriteFile (hd, "\n", 1, &n, NULL);
373	twoaday	26	return 0;
374	twoaday	2	}
375			c->pwd_init = 0;
376			}
377	twoaday	23	if (c->cancel) {
378	twoaday	24	WriteFile (hd, "\n", 1, &n, NULL);
379	twoaday	26	return 0;
380	twoaday	23	}
381	twoaday	2
382	twoaday	24	WriteFile (hd, c->pwd, strlen (c->pwd), &n, NULL);
383			WriteFile (hd, "\n", 1, &n, NULL);
384	twoaday	23	return 0;
385			}
386	twoaday	2
387
388	twoaday	23	/* Initialize the given passphrase callback @cb with the
389			used gpgme context @ctx, the command @cmd and a title
390			@title for the dialog. */
391			void
392			set_gpg_passphrase_cb (passphrase_cb_s *cb, gpgme_ctx_t ctx,
393			int cmd, HWND hwnd, const char *title)
394			{
395			memset (cb, 0, sizeof *cb);
396			cb->gpg_cmd = cmd;
397	twoaday	26	cb->bad_pwd = 0;
398	twoaday	23	cb->is_card = 0;
399			cb->cancel = 0;
400			cb->hwnd = hwnd;
401			cb->pwd_init = 1;
402			free_if_alloc (cb->title);
403			cb->title = m_strdup (title);
404			if (!cb->title)
405			BUG (NULL);
406			gpgme_set_passphrase_cb (ctx, passphrase_cb, cb);
407			cb->gpg = ctx;
408			}
409	twoaday	2
410	twoaday	23
411			/* Release a passphrase callback @ctx. */
412	twoaday	2	void
413	twoaday	23	release_gpg_passphrase_cb (passphrase_cb_s *ctx)
414	twoaday	2	{
415	twoaday	23	if (!ctx)
416			return;
417			sfree_if_alloc (ctx->pwd);
418			free_if_alloc (ctx->title);
419			}
420	twoaday	22
421	twoaday	26
422	twoaday	23	/* Simple check to measure passphrase (@pass) quality.
423			Return value: 0 on success. */
424	twoaday	22	int
425			check_passwd_quality (const char *pass, int strict)
426			{
427			int i, nd=0, nc=0, n;
428
429			n = strlen (pass);
430			if (n < 8)
431			return -1;
432
433			for (i=0; i < n; i++) {
434			if (isdigit (pass[i])) nd++;
435			if (isalpha (pass[i])) nc++;
436			}
437
438			if (nd == n \|\| nc == n)
439			return -1;
440
441			return 0;
442			}