trunk/Src/wptPassphraseCB.cpp

/* wptPassphraseCB.cpp - GPGME Passphrase Callback
 *      Copyright (C) 2001, 2002, 2003, 2005, 2006 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 
 */

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

#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 "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)


void ListBox_AddString_utf8 (HWND lb, const char *txt);

/* Overwrite passphrase and free memory. */
static void
burn_passphrase (char **pwd)
{
    char *pass = *pwd;
    wipememory (pass, 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=NULL;
    gpgme_sign_result_t res_sig=NULL;
    gpgme_key_t key;
    gpgme_recipient_t recip=NULL, r;
    void *item;
    const char *id;
    char *info;
    int n;

    switch (msg) {
    case WM_ACTIVATE:
        safe_edit_control_init (dlg, item_ctrl_id (c->gpg_cmd));
        break;

    case WM_DESTROY:
        safe_edit_control_free (dlg, item_ctrl_id (c->gpg_cmd));
        break;

    case WM_INITDIALOG:
        c = (passphrase_cb_s *)lparam;
        if (!c)
            BUG (0);
        SetDlgItemText (dlg, IDCANCEL, _("&Cancel"));
        SetDlgItemText (dlg, IDC_DECRYPT_HIDE, _("&Hide Typing"));
        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) {
            SetDlgItemText (dlg, IDC_DECRYPT_SIGN_HIDE, _("&Hide Typing"));
            CheckDlgButton (dlg, IDC_DECRYPT_SIGN_HIDE, BST_CHECKED);
        }
        /* Because it depends on the order the keys are stored in the
           keyring whether res->recipients is complete or not, we also
           support that the recipients were externally extracted and then
           we use this list. */
        if (c->recipients)
            recip = c->recipients; /* recipients were already extracted. */
        else {
            res = gpgme_op_decrypt_result (c->gpg);
            if (res && res->recipients)
                recip = res->recipients;
        }
        if (recip != NULL && c->gpg_cmd == GPG_CMD_DECRYPT) {
            for (r = recip; r; r = r->next) {
                get_pubkey (r->keyid, &key);
                if (key) {
                    gpgme_user_id_t u = key->uids;

                    id = u->name;
                    if (!id)
                        id = _("Invalid User ID");
                    n = 32+strlen (id)+1+4+strlen (r->keyid)+1;
                    if (u->email)
                        n += strlen (u->email)+1;
                    info = new char [n+1];
                    if (!info)
                        BUG (NULL);
                    if (!u->email || strlen (u->email) < 1)
                        sprintf (info, "%s (%s, 0x%s)", id,
                                 get_key_pubalgo (r->pubkey_algo), r->keyid+8);
                    else
                        sprintf (info, "%s <%s> (%s, 0x%s)", id, u->email,
                                 get_key_pubalgo (r->pubkey_algo), r->keyid+8);
                }
                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_AddString_utf8 (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_utf8 (dlg, IDC_DECRYPT_MSG, c->info);
        }
        else {
            SetFocus (GetDlgItem (dlg, IDC_DECRYPT_SIGN_PWD));
            SetDlgItemText_utf8 (dlg, IDC_DECRYPT_SIGN_MSG, c->info);
        }
        center_window (dlg, NULL);
        SetForegroundWindow (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:  
                /* XXX: 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);
                    SafeGetDlgItemText (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_sig)) {
                    if (agent_get_cache (c->keyid, &item))                      
                        agent_unlock_cache_entry (&item);
                    else 
                        agent_put_cache (c->keyid, c->pwd, reg_prefs.cache_time);
                }
                c->cancel = 0;
                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) {
        log_debug ("parse_gpg_keyid: error '%s'\r\n", pass_info);
        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];
    char mainkey[16+1];
    char *p;
    int n=0;

    algo = (gpgme_pubkey_algo_t)0;
    /* Each uid_hint contains a long key-ID so it is at least 16 bytes. */
    if (strlen (uid_hint) < 17) {
        *desc = 0;
        log_debug ("parse_gpg_description: error '%s'\r\n", uid_hint);
        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 */

    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_hint, 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_hint, get_key_pubalgo (algo), usedkey+8);
    return 0;
}


/* Extract the serial number from the card ID @id and return it. */
const char*
extract_serial_no (const char *id)
{
    static char buf[8];
    char *p;

    p = strchr (id, '/');
    if (!p) {
        log_debug ("extract_serial_no: error '%s'\r\n", id);
        return NULL;
    }
    strncpy (buf, id+(p-id)-6, 6);
    return buf;
}


/* 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=NULL, *pass;
    DWORD n;
    int rc = 0;

    if (!c) {
        log_debug ("passphrase_cb: error '!c'\r\n");
        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 pos=2;
            c->sym.sym_algo = atoi (passphrase_info);
            if (c->sym.sym_algo > 9)
                pos++;
            /* XXX: be more strict. */
            c->sym.s2k_mode = atoi (passphrase_info+pos);
            c->sym.s2k_hash = atoi (passphrase_info+pos+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")) {
            const char *s=passphrase_info;
            while (s && *s && *s != 'D')
                s++;
            _snprintf (c->info, sizeof c->info-1,
                       _("Please enter the PIN to unlock your secret card key\n"
                         "Card: %s"), extract_serial_no (s));
            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) {
            if (!WriteFile (hd, "\n", 1, &n, NULL))
                log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
            return 0;
        }
        c->pwd_init = 0;
    }
    if (c->cancel) {
        if (!WriteFile (hd, "\n", 1, &n, NULL))
            log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
        return 0;
    }

    if (!WriteFile (hd, c->pwd, strlen (c->pwd), &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;
}


/* 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)
{
    gpgme_recipient_t r, n;

    if (!ctx)
        return;
    sfree_if_alloc (ctx->pwd);
    free_if_alloc (ctx->title);
    r = ctx->recipients;
    while (r) {
        n = r->next;
        safe_free (r->keyid);
        safe_free (r);
        r = n;
    }
}


/* 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++;
    }

    /* check that the passphrase contains letters and numbers. */
    if (nd == n || nc == n)
        return -1;

    return 0;
}
1	werner	36	/* wptPassphraseCB.cpp - GPGME Passphrase Callback
2	twoaday	204	* Copyright (C) 2001, 2002, 2003, 2005, 2006 Timo Schulz
3	werner	36	* Copyright (C) 2005 g10 Code GmbH
4			*
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			#ifdef HAVE_CONFIG_H
23			#include <config.h>
24			#endif
25
26			#include <windows.h>
27			#include <ctype.h>
28
29	werner	47	#include "resource.h"
30	werner	36	#include "wptNLS.h"
31			#include "wptW32API.h"
32			#include "wptVersion.h"
33			#include "wptGPG.h"
34			#include "wptCommonCtl.h"
35			#include "wptContext.h"
36			#include "wptDlgs.h"
37			#include "wptErrors.h"
38			#include "wptTypes.h"
39	werner	48	#include "wptKeylist.h"
40	werner	36	#include "wptAgent.h"
41			#include "wptRegistry.h"
42
43			const char* get_symkey_algo (int algo);
44
45	twoaday	181	#define item_ctrl_id(cmd) \
46	werner	36	((cmd) == GPG_CMD_DECRYPT? IDC_DECRYPT_PWD : IDC_DECRYPT_SIGN_PWD)
47
48			#define item_ctrl_id2(cmd) \
49			((cmd) == GPG_CMD_DECRYPT? IDC_DECRYPT_HIDE : IDC_DECRYPT_SIGN_HIDE)
50
51
52	twoaday	204	void ListBox_AddString_utf8 (HWND lb, const char *txt);
53
54	werner	36	/* Overwrite passphrase and free memory. */
55			static void
56			burn_passphrase (char **pwd)
57			{
58			char pass = pwd;
59			wipememory (pass, strlen (pass));
60			delete []pass;
61			*pwd = NULL;
62			}
63
64
65			/* Dialog procedure for the passphrase callback. */
66			static BOOL CALLBACK
67			passphrase_callback_proc (HWND dlg, UINT msg, WPARAM wparam, LPARAM lparam)
68			{
69	twoaday	77	static passphrase_cb_s *c;
70			gpgme_decrypt_result_t res=NULL;
71			gpgme_sign_result_t res_sig=NULL;
72	werner	36	gpgme_key_t key;
73	twoaday	69	gpgme_recipient_t recip=NULL, r;
74			void *item;
75	werner	36	const char *id;
76			char *info;
77			int n;
78
79			switch (msg) {
80	twoaday	181	case WM_ACTIVATE:
81			safe_edit_control_init (dlg, item_ctrl_id (c->gpg_cmd));
82			break;
83
84			case WM_DESTROY:
85			safe_edit_control_free (dlg, item_ctrl_id (c->gpg_cmd));
86			break;
87
88	werner	36	case WM_INITDIALOG:
89			c = (passphrase_cb_s *)lparam;
90			if (!c)
91			BUG (0);
92	twoaday	105	SetDlgItemText (dlg, IDCANCEL, _("&Cancel"));
93	twoaday	85	SetDlgItemText (dlg, IDC_DECRYPT_HIDE, _("&Hide Typing"));
94	werner	36	SetWindowText (dlg, c->title);
95			if (c->gpg_cmd == GPG_CMD_DECRYPT) {
96			SetDlgItemText (dlg, IDC_DECRYPT_LISTINF,
97			_("Encrypted with the following public key(s)"));
98			CheckDlgButton (dlg, IDC_DECRYPT_HIDE, BST_CHECKED);
99			}
100	twoaday	95	else if (c->gpg_cmd == GPG_CMD_SIGN) {
101			SetDlgItemText (dlg, IDC_DECRYPT_SIGN_HIDE, _("&Hide Typing"));
102	werner	36	CheckDlgButton (dlg, IDC_DECRYPT_SIGN_HIDE, BST_CHECKED);
103	twoaday	95	}
104	twoaday	179	/* Because it depends on the order the keys are stored in the
105			keyring whether res->recipients is complete or not, we also
106			support that the recipients were externally extracted and then
107			we use this list. */
108	werner	36	if (c->recipients)
109			recip = c->recipients; /* recipients were already extracted. */
110			else {
111			res = gpgme_op_decrypt_result (c->gpg);
112			if (res && res->recipients)
113			recip = res->recipients;
114			}
115			if (recip != NULL && c->gpg_cmd == GPG_CMD_DECRYPT) {
116	twoaday	179	for (r = recip; r; r = r->next) {
117	werner	36	get_pubkey (r->keyid, &key);
118			if (key) {
119	twoaday	160	gpgme_user_id_t u = key->uids;
120
121			id = u->name;
122	werner	36	if (!id)
123			id = _("Invalid User ID");
124	twoaday	204	n = 32+strlen (id)+1+4+strlen (r->keyid)+1;
125	twoaday	160	if (u->email)
126			n += strlen (u->email)+1;
127			info = new char [n+1];
128	werner	36	if (!info)
129			BUG (NULL);
130	twoaday	160	if (!u->email \|\| strlen (u->email) < 1)
131	twoaday	204	sprintf (info, "%s (%s, 0x%s)", id,
132	twoaday	160	get_key_pubalgo (r->pubkey_algo), r->keyid+8);
133			else
134	twoaday	204	sprintf (info, "%s <%s> (%s, 0x%s)", id, u->email,
135	twoaday	160	get_key_pubalgo (r->pubkey_algo), r->keyid+8);
136	werner	36	}
137			else {
138			info = new char [32 + strlen (r->keyid)+1 + 4];
139			if (!info)
140			BUG (NULL);
141			sprintf (info, _("Unknown key ID (%s, 0x%s)"),
142			get_key_pubalgo (r->pubkey_algo), r->keyid+8);
143			}
144	twoaday	204	ListBox_AddString_utf8 (GetDlgItem (dlg, IDC_DECRYPT_LIST), info);
145	werner	36	free_if_alloc (info);
146			}
147			}
148			else if (c->gpg_cmd == GPG_CMD_DECRYPT)
149			EnableWindow (GetDlgItem (dlg, IDC_DECRYPT_LIST), FALSE);
150			SetDlgItemText (dlg, c->gpg_cmd == GPG_CMD_DECRYPT?
151			IDC_DECRYPT_PWDINFO : IDC_DECRYPT_SIGN_PWDINFO,
152			c->bad_pwd? _("Bad passphrase; Enter passphrase again") :
153			_("Please enter your passphrase"));
154			if (c->gpg_cmd == GPG_CMD_DECRYPT) {
155			SetFocus (GetDlgItem (dlg, IDC_DECRYPT_PWD));
156			if (res && !res->recipients) {
157			const char *s = _("Symmetric encryption.\n"
158			"%s encrypted data.");
159			const char *alg = get_symkey_algo (c->sym.sym_algo);
160			info = new char[strlen (s) + strlen (alg) + 2];
161			if (!info)
162			BUG (NULL);
163			sprintf (info, s, alg);
164			SetDlgItemText (dlg, IDC_DECRYPT_MSG, info);
165			free_if_alloc (info);
166			}
167			else
168	twoaday	204	SetDlgItemText_utf8 (dlg, IDC_DECRYPT_MSG, c->info);
169	werner	36	}
170			else {
171	twoaday	204	SetFocus (GetDlgItem (dlg, IDC_DECRYPT_SIGN_PWD));
172			SetDlgItemText_utf8 (dlg, IDC_DECRYPT_SIGN_MSG, c->info);
173	werner	36	}
174			center_window (dlg, NULL);
175			SetForegroundWindow (dlg);
176			return FALSE;
177
178			case WM_SYSCOMMAND:
179			if (LOWORD (wparam) == SC_CLOSE) {
180			SetDlgItemText (dlg, item_ctrl_id (c->gpg_cmd), "");
181			c->cancel = 1;
182			EndDialog (dlg, TRUE);
183			}
184			break;
185
186			case WM_COMMAND:
187			switch (HIWORD (wparam)) {
188			case BN_CLICKED:
189			if (LOWORD (wparam) == IDC_DECRYPT_HIDE
190			\|\| LOWORD (wparam) == IDC_DECRYPT_SIGN_HIDE) {
191			HWND hwnd;
192			int hide = IsDlgButtonChecked (dlg, item_ctrl_id2 (c->gpg_cmd));
193			hwnd = GetDlgItem (dlg, item_ctrl_id (c->gpg_cmd));
194			SendMessage (hwnd, EM_SETPASSWORDCHAR, hide? '*' : 0, 0);
195			SetFocus (hwnd);
196			}
197			}
198
199			switch (LOWORD (wparam)) {
200			case IDOK:
201			/* XXX: the item is even cached when the passphrase is not
202			correct, which means that the user needs to delete all
203			cached entries to continue. */
204			if (c->pwd)
205			burn_passphrase (&c->pwd);
206			n = item_get_text_length (dlg, item_ctrl_id (c->gpg_cmd));
207			if (!n) {
208			c->pwd = new char[2];
209			if (!c->pwd)
210			BUG (NULL);
211			strcpy (c->pwd, "");
212			}
213			else {
214			c->pwd = new char[n+2];
215			if (!c->pwd)
216			BUG (NULL);
217	twoaday	181	SafeGetDlgItemText (dlg, item_ctrl_id (c->gpg_cmd),
218			c->pwd, n+1);
219	werner	36	}
220			res = gpgme_op_decrypt_result (c->gpg);
221			if (!res)
222	twoaday	77	res_sig = gpgme_op_sign_result (c->gpg);
223			if (reg_prefs.cache_time > 0 && !c->is_card &&
224			(res \|\| res_sig)) {
225			if (agent_get_cache (c->keyid, &item))
226	werner	36	agent_unlock_cache_entry (&item);
227	twoaday	77	else
228	werner	36	agent_put_cache (c->keyid, c->pwd, reg_prefs.cache_time);
229			}
230			c->cancel = 0;
231			EndDialog (dlg, TRUE);
232			return TRUE;
233
234			case IDCANCEL:
235			SetDlgItemText (dlg, item_ctrl_id (c->gpg_cmd), "");
236			c->cancel = 1;
237			EndDialog (dlg, FALSE);
238			return FALSE;
239			}
240			break;
241			}
242
243			return FALSE;
244			}
245
246
247			/* Extract the main keyid from @pass_info.
248			Return value: long main keyid or NULL for an error. */
249			static const char*
250			parse_gpg_keyid (const char *pass_info)
251			{
252			static char keyid[16+1];
253
254			/* XXX: check for leading alpha-chars? */
255	twoaday	77	if (strlen (pass_info) < 16) {
256			log_debug ("parse_gpg_keyid: error '%s'\r\n", pass_info);
257	werner	36	return NULL;
258	twoaday	77	}
259	werner	36	/* the format of the desc buffer looks like this:
260			request_keyid[16] main_keyid[16] keytype[1] keylength[4]
261			we use the main keyid to use only one cache entry. */
262			strncpy (keyid, pass_info+17, 16);
263			keyid[16] = 0;
264			return keyid;
265			}
266
267
268			/* Parse the information in @uid_hint and @pass_info to generate
269			a input message for the user in @desc. */
270			static int
271			parse_gpg_description (const char uid_hint, const char pass_info,
272			char *desc, int size)
273			{
274			gpgme_pubkey_algo_t algo;
275			char usedkey[16+1];
276			char mainkey[16+1];
277	twoaday	204	char *p;
278	werner	36	int n=0;
279
280	twoaday	69	algo = (gpgme_pubkey_algo_t)0;
281	werner	36	/* Each uid_hint contains a long key-ID so it is at least 16 bytes. */
282			if (strlen (uid_hint) < 17) {
283			*desc = 0;
284	twoaday	77	log_debug ("parse_gpg_description: error '%s'\r\n", uid_hint);
285	werner	36	return -1;
286			}
287
288			while (p = strsep ((char**)&pass_info, " ")) {
289			switch (n++) {
290			case 0: strncpy (mainkey, p, 16); mainkey[16] = 0; break;
291			case 1: strncpy (usedkey, p, 16); usedkey[16] = 0; break;
292			case 2: algo = (gpgme_pubkey_algo_t)atol (p); break;
293			}
294			}
295			uid_hint += 16; /* skip keyid */
296			uid_hint += 1; /* space */
297
298			if (strcmp (usedkey, mainkey))
299			_snprintf (desc, size-1,
300			_("You need a passphrase to unlock the secret key for\n"
301			"user: \"%s\"\n"
302			"%s key, ID %s (main key ID %s)\n"),
303	twoaday	204	uid_hint, get_key_pubalgo (algo), usedkey+8, mainkey+8);
304	werner	36	else if (!strcmp (usedkey, mainkey))
305			_snprintf (desc, size-1,
306			_("You need a passphrase to unlock the secret key for\n"
307			"user: \"%s\"\n"
308			"%s key, ID %s\n"),
309	twoaday	204	uid_hint, get_key_pubalgo (algo), usedkey+8);
310	werner	36	return 0;
311			}
312
313
314			/* Extract the serial number from the card ID @id and return it. */
315			const char*
316			extract_serial_no (const char *id)
317			{
318			static char buf[8];
319			char *p;
320
321			p = strchr (id, '/');
322	twoaday	77	if (!p) {
323			log_debug ("extract_serial_no: error '%s'\r\n", id);
324	werner	36	return NULL;
325	twoaday	77	}
326	werner	36	strncpy (buf, id+(p-id)-6, 6);
327			return buf;
328			}
329
330
331			/* Passphrase callback with the ability to support caching. */
332			gpgme_error_t
333			passphrase_cb (void hook, const char uid_hint,
334			const char *passphrase_info,
335			int prev_was_bad, int fd)
336			{
337			passphrase_cb_s c = (passphrase_cb_s)hook;
338			HANDLE hd = (HANDLE)fd;
339			void *item;
340	twoaday	69	const char keyid=NULL, pass;
341	werner	36	DWORD n;
342	twoaday	77	int rc = 0;
343	werner	36
344	twoaday	77	if (!c) {
345			log_debug ("passphrase_cb: error '!c'\r\n");
346	werner	36	return gpg_error (GPG_ERR_INV_ARG);
347	twoaday	77	}
348	werner	36	c->bad_pwd = prev_was_bad? 1 : 0;
349			if (prev_was_bad && !c->cancel) {
350			if (c->pwd)
351			burn_passphrase (&c->pwd);
352			agent_del_cache (c->keyid);
353			c->pwd_init = 1;
354			}
355
356			if (passphrase_info) {
357			if (strlen (passphrase_info) < 16 &&
358			!strstr (passphrase_info, "OPENPGP")) {
359			/* assume symetric encryption. */
360	twoaday	69	int pos=2;
361	werner	36	c->sym.sym_algo = atoi (passphrase_info);
362			if (c->sym.sym_algo > 9)
363	twoaday	69	pos++;
364	werner	36	/* XXX: be more strict. */
365	twoaday	69	c->sym.s2k_mode = atoi (passphrase_info+pos);
366			c->sym.s2k_hash = atoi (passphrase_info+pos+2);
367	werner	36	}
368
369			keyid = parse_gpg_keyid (passphrase_info);
370	twoaday	77	pass = agent_get_cache (keyid+8, &item);
371	werner	36	if (pass) {
372			agent_unlock_cache_entry (&item);
373			c->pwd_init = 0;
374			if (!WriteFile (hd, pass, strlen (pass), &n, NULL))
375			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
376			if (!WriteFile (hd, "\n", 1, &n, NULL))
377			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
378			return 0;
379			}
380			}
381
382			if (c->pwd_init) {
383			if (keyid && strlen (keyid) == 16)
384			strcpy (c->keyid, keyid+8);
385
386			/* if @passphrase_info contains 'OPENPGP' we assume a smart card
387			has been used. */
388			if (strstr (passphrase_info, "OPENPGP")) {
389			const char *s=passphrase_info;
390			while (s && s && s != 'D')
391			s++;
392			_snprintf (c->info, sizeof c->info-1,
393			_("Please enter the PIN to unlock your secret card key\n"
394			"Card: %s"), extract_serial_no (s));
395			c->is_card = 1;
396			}
397			else if (uid_hint)
398			parse_gpg_description (uid_hint, passphrase_info,
399	twoaday	181	c->info, sizeof (c->info) - 1);
400	werner	36	if (c->gpg_cmd == GPG_CMD_DECRYPT) {
401			rc = DialogBoxParam (glob_hinst, (LPCSTR)IDD_WINPT_DECRYPT,
402			(HWND)c->hwnd, passphrase_callback_proc,
403			(LPARAM)c);
404			}
405			else if (c->gpg_cmd == GPG_CMD_SIGN) {
406			rc = DialogBoxParam (glob_hinst, (LPCSTR)IDD_WINPT_DECRYPT_SIGN,
407			(HWND)c->hwnd, passphrase_callback_proc,
408			(LPARAM)c);
409			}
410			if (rc == -1) {
411			if (!WriteFile (hd, "\n", 1, &n, NULL))
412			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
413			return 0;
414			}
415			c->pwd_init = 0;
416			}
417			if (c->cancel) {
418			if (!WriteFile (hd, "\n", 1, &n, NULL))
419			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
420			return 0;
421			}
422
423	twoaday	77	if (!WriteFile (hd, c->pwd, strlen (c->pwd), &n, NULL))
424			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
425			if (!WriteFile (hd, "\n", 1, &n, NULL))
426			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
427	werner	36	return 0;
428			}
429
430
431			/* Initialize the given passphrase callback @cb with the
432			used gpgme context @ctx, the command @cmd and a title
433			@title for the dialog. */
434			void
435			set_gpg_passphrase_cb (passphrase_cb_s *cb, gpgme_ctx_t ctx,
436			int cmd, HWND hwnd, const char *title)
437			{
438			memset (cb, 0, sizeof *cb);
439			cb->gpg_cmd = cmd;
440			cb->bad_pwd = 0;
441			cb->is_card = 0;
442			cb->cancel = 0;
443			cb->hwnd = hwnd;
444			cb->pwd_init = 1;
445			free_if_alloc (cb->title);
446			cb->title = m_strdup (title);
447			if (!cb->title)
448			BUG (NULL);
449			gpgme_set_passphrase_cb (ctx, passphrase_cb, cb);
450			cb->gpg = ctx;
451			}
452
453
454			/* Release a passphrase callback @ctx. */
455			void
456			release_gpg_passphrase_cb (passphrase_cb_s *ctx)
457			{
458			gpgme_recipient_t r, n;
459
460			if (!ctx)
461			return;
462			sfree_if_alloc (ctx->pwd);
463			free_if_alloc (ctx->title);
464			r = ctx->recipients;
465			while (r) {
466			n = r->next;
467			safe_free (r->keyid);
468			safe_free (r);
469			r = n;
470			}
471			}
472
473
474			/* Simple check to measure passphrase (@pass) quality.
475			Return value: 0 on success. */
476			int
477			check_passwd_quality (const char *pass, int strict)
478			{
479			int i, nd=0, nc=0, n;
480
481			n = strlen (pass);
482			if (n < 8)
483			return -1;
484
485			for (i=0; i < n; i++) {
486			if (isdigit (pass[i]))
487			nd++;
488			if (isalpha (pass[i]))
489			nc++;
490			}
491
492			/* check that the passphrase contains letters and numbers. */
493			if (nd == n \|\| nc == n)
494			return -1;
495
496			return 0;
497			}