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 
 */

#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 "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;
    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_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);
        }
        if (c->recipients)
            recip = c->recipients; /* recipients were already extracted. */
        else {
            /* XXX: not all ENCRYPT_TO entries are listed here. */
            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 = 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:  
                /* 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);
                    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_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 *uid, *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 */

    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;
}


/* 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			* Copyright (C) 2001, 2002, 2003, 2005 Timo Schulz
3			* 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 "wptUTF8.h"
38			#include "wptErrors.h"
39			#include "wptTypes.h"
40	werner	48	#include "wptKeylist.h"
41	werner	36	#include "wptAgent.h"
42			#include "wptRegistry.h"
43
44			const char* get_symkey_algo (int algo);
45
46			#define item_ctrl_id( cmd ) \
47			((cmd) == GPG_CMD_DECRYPT? IDC_DECRYPT_PWD : IDC_DECRYPT_SIGN_PWD)
48
49			#define item_ctrl_id2(cmd) \
50			((cmd) == GPG_CMD_DECRYPT? IDC_DECRYPT_HIDE : IDC_DECRYPT_SIGN_HIDE)
51
52
53			/* Overwrite passphrase and free memory. */
54			static void
55			burn_passphrase (char **pwd)
56			{
57			char pass = pwd;
58			wipememory (pass, strlen (pass));
59			delete []pass;
60			*pwd = NULL;
61			}
62
63
64			/* Dialog procedure for the passphrase callback. */
65			static BOOL CALLBACK
66			passphrase_callback_proc (HWND dlg, UINT msg, WPARAM wparam, LPARAM lparam)
67			{
68	twoaday	77	static passphrase_cb_s *c;
69			gpgme_decrypt_result_t res=NULL;
70			gpgme_sign_result_t res_sig=NULL;
71	werner	36	gpgme_key_t key;
72	twoaday	69	gpgme_recipient_t recip=NULL, r;
73			void *item;
74	werner	36	const char *id;
75			char *info;
76			int n;
77
78			switch (msg) {
79			case WM_INITDIALOG:
80			c = (passphrase_cb_s *)lparam;
81			if (!c)
82			BUG (0);
83	twoaday	105	SetDlgItemText (dlg, IDCANCEL, _("&Cancel"));
84	twoaday	85	SetDlgItemText (dlg, IDC_DECRYPT_HIDE, _("&Hide Typing"));
85	werner	36	SetWindowText (dlg, c->title);
86			if (c->gpg_cmd == GPG_CMD_DECRYPT) {
87			SetDlgItemText (dlg, IDC_DECRYPT_LISTINF,
88			_("Encrypted with the following public key(s)"));
89			CheckDlgButton (dlg, IDC_DECRYPT_HIDE, BST_CHECKED);
90			}
91	twoaday	95	else if (c->gpg_cmd == GPG_CMD_SIGN) {
92			SetDlgItemText (dlg, IDC_DECRYPT_SIGN_HIDE, _("&Hide Typing"));
93	werner	36	CheckDlgButton (dlg, IDC_DECRYPT_SIGN_HIDE, BST_CHECKED);
94	twoaday	95	}
95	werner	36	if (c->recipients)
96			recip = c->recipients; /* recipients were already extracted. */
97			else {
98			/* XXX: not all ENCRYPT_TO entries are listed here. */
99			res = gpgme_op_decrypt_result (c->gpg);
100			if (res && res->recipients)
101			recip = res->recipients;
102			}
103			if (recip != NULL && c->gpg_cmd == GPG_CMD_DECRYPT) {
104			for (r = res->recipients; r; r = r->next) {
105			get_pubkey (r->keyid, &key);
106			if (key) {
107			char *uid;
108			id = key->uids->name;
109			if (!id)
110			id = _("Invalid User ID");
111			uid = utf8_to_wincp (id, strlen (id));
112			info = new char [32+strlen (uid)+1 + 4 + strlen (r->keyid)+1
113			+ strlen (key->uids->email)+1];
114			if (!info)
115			BUG (NULL);
116			sprintf (info, "%s <%s> (%s, 0x%s)", uid, key->uids->email,
117			get_key_pubalgo (r->pubkey_algo), r->keyid+8);
118			free (uid);
119
120			}
121			else {
122			info = new char [32 + strlen (r->keyid)+1 + 4];
123			if (!info)
124			BUG (NULL);
125			sprintf (info, _("Unknown key ID (%s, 0x%s)"),
126			get_key_pubalgo (r->pubkey_algo), r->keyid+8);
127			}
128			listbox_add_string (GetDlgItem (dlg, IDC_DECRYPT_LIST), info);
129			free_if_alloc (info);
130			}
131			}
132			else if (c->gpg_cmd == GPG_CMD_DECRYPT)
133			EnableWindow (GetDlgItem (dlg, IDC_DECRYPT_LIST), FALSE);
134			SetDlgItemText (dlg, c->gpg_cmd == GPG_CMD_DECRYPT?
135			IDC_DECRYPT_PWDINFO : IDC_DECRYPT_SIGN_PWDINFO,
136			c->bad_pwd? _("Bad passphrase; Enter passphrase again") :
137			_("Please enter your passphrase"));
138			if (c->gpg_cmd == GPG_CMD_DECRYPT) {
139			SetFocus (GetDlgItem (dlg, IDC_DECRYPT_PWD));
140			if (res && !res->recipients) {
141			const char *s = _("Symmetric encryption.\n"
142			"%s encrypted data.");
143			const char *alg = get_symkey_algo (c->sym.sym_algo);
144			info = new char[strlen (s) + strlen (alg) + 2];
145			if (!info)
146			BUG (NULL);
147			sprintf (info, s, alg);
148			SetDlgItemText (dlg, IDC_DECRYPT_MSG, info);
149			free_if_alloc (info);
150			}
151			else
152			SetDlgItemText (dlg, IDC_DECRYPT_MSG, c->info);
153			}
154			else {
155			SetFocus( GetDlgItem (dlg, IDC_DECRYPT_SIGN_PWD));
156			SetDlgItemText (dlg, IDC_DECRYPT_SIGN_MSG, c->info);
157			}
158			center_window (dlg, NULL);
159			SetForegroundWindow (dlg);
160			set_active_window (dlg);
161			return FALSE;
162
163			case WM_SYSCOMMAND:
164			if (LOWORD (wparam) == SC_CLOSE) {
165			SetDlgItemText (dlg, item_ctrl_id (c->gpg_cmd), "");
166			c->cancel = 1;
167			EndDialog (dlg, TRUE);
168			}
169			break;
170
171			case WM_COMMAND:
172			switch (HIWORD (wparam)) {
173			case BN_CLICKED:
174			if (LOWORD (wparam) == IDC_DECRYPT_HIDE
175			\|\| LOWORD (wparam) == IDC_DECRYPT_SIGN_HIDE) {
176			HWND hwnd;
177			int hide = IsDlgButtonChecked (dlg, item_ctrl_id2 (c->gpg_cmd));
178			hwnd = GetDlgItem (dlg, item_ctrl_id (c->gpg_cmd));
179			SendMessage (hwnd, EM_SETPASSWORDCHAR, hide? '*' : 0, 0);
180			SetFocus (hwnd);
181			}
182			}
183
184			switch (LOWORD (wparam)) {
185			case IDOK:
186			/* XXX: the item is even cached when the passphrase is not
187			correct, which means that the user needs to delete all
188			cached entries to continue. */
189			if (c->pwd)
190			burn_passphrase (&c->pwd);
191			n = item_get_text_length (dlg, item_ctrl_id (c->gpg_cmd));
192			if (!n) {
193			c->pwd = new char[2];
194			if (!c->pwd)
195			BUG (NULL);
196			strcpy (c->pwd, "");
197			}
198			else {
199			c->pwd = new char[n+2];
200			if (!c->pwd)
201			BUG (NULL);
202			GetDlgItemText (dlg, item_ctrl_id (c->gpg_cmd), c->pwd, n+1);
203			}
204			res = gpgme_op_decrypt_result (c->gpg);
205			if (!res)
206	twoaday	77	res_sig = gpgme_op_sign_result (c->gpg);
207			if (reg_prefs.cache_time > 0 && !c->is_card &&
208			(res \|\| res_sig)) {
209			if (agent_get_cache (c->keyid, &item))
210	werner	36	agent_unlock_cache_entry (&item);
211	twoaday	77	else
212	werner	36	agent_put_cache (c->keyid, c->pwd, reg_prefs.cache_time);
213			}
214			c->cancel = 0;
215			EndDialog (dlg, TRUE);
216			return TRUE;
217
218			case IDCANCEL:
219			SetDlgItemText (dlg, item_ctrl_id (c->gpg_cmd), "");
220			c->cancel = 1;
221			EndDialog (dlg, FALSE);
222			return FALSE;
223			}
224			break;
225			}
226
227			return FALSE;
228			}
229
230
231			/* Extract the main keyid from @pass_info.
232			Return value: long main keyid or NULL for an error. */
233			static const char*
234			parse_gpg_keyid (const char *pass_info)
235			{
236			static char keyid[16+1];
237
238			/* XXX: check for leading alpha-chars? */
239	twoaday	77	if (strlen (pass_info) < 16) {
240			log_debug ("parse_gpg_keyid: error '%s'\r\n", pass_info);
241	werner	36	return NULL;
242	twoaday	77	}
243	werner	36	/* the format of the desc buffer looks like this:
244			request_keyid[16] main_keyid[16] keytype[1] keylength[4]
245			we use the main keyid to use only one cache entry. */
246			strncpy (keyid, pass_info+17, 16);
247			keyid[16] = 0;
248			return keyid;
249			}
250
251
252			/* Parse the information in @uid_hint and @pass_info to generate
253			a input message for the user in @desc. */
254			static int
255			parse_gpg_description (const char uid_hint, const char pass_info,
256			char *desc, int size)
257			{
258			gpgme_pubkey_algo_t algo;
259			char usedkey[16+1];
260			char mainkey[16+1];
261			char uid, p;
262			int n=0;
263
264	twoaday	69	algo = (gpgme_pubkey_algo_t)0;
265	werner	36	/* Each uid_hint contains a long key-ID so it is at least 16 bytes. */
266			if (strlen (uid_hint) < 17) {
267			*desc = 0;
268	twoaday	77	log_debug ("parse_gpg_description: error '%s'\r\n", uid_hint);
269	werner	36	return -1;
270			}
271
272			while (p = strsep ((char**)&pass_info, " ")) {
273			switch (n++) {
274			case 0: strncpy (mainkey, p, 16); mainkey[16] = 0; break;
275			case 1: strncpy (usedkey, p, 16); usedkey[16] = 0; break;
276			case 2: algo = (gpgme_pubkey_algo_t)atol (p); break;
277			}
278			}
279			uid_hint += 16; /* skip keyid */
280			uid_hint += 1; /* space */
281
282			uid = utf8_to_wincp (uid_hint, strlen (uid_hint));
283
284			if (strcmp (usedkey, mainkey))
285			_snprintf (desc, size-1,
286			_("You need a passphrase to unlock the secret key for\n"
287			"user: \"%s\"\n"
288			"%s key, ID %s (main key ID %s)\n"),
289			uid, get_key_pubalgo (algo), usedkey+8, mainkey+8);
290			else if (!strcmp (usedkey, mainkey))
291			_snprintf (desc, size-1,
292			_("You need a passphrase to unlock the secret key for\n"
293			"user: \"%s\"\n"
294			"%s key, ID %s\n"),
295			uid, get_key_pubalgo (algo), usedkey+8);
296			free (uid);
297			return 0;
298			}
299
300
301			/* Extract the serial number from the card ID @id and return it. */
302			const char*
303			extract_serial_no (const char *id)
304			{
305			static char buf[8];
306			char *p;
307
308			p = strchr (id, '/');
309	twoaday	77	if (!p) {
310			log_debug ("extract_serial_no: error '%s'\r\n", id);
311	werner	36	return NULL;
312	twoaday	77	}
313	werner	36	strncpy (buf, id+(p-id)-6, 6);
314			return buf;
315			}
316
317
318			/* Passphrase callback with the ability to support caching. */
319			gpgme_error_t
320			passphrase_cb (void hook, const char uid_hint,
321			const char *passphrase_info,
322			int prev_was_bad, int fd)
323			{
324			passphrase_cb_s c = (passphrase_cb_s)hook;
325			HANDLE hd = (HANDLE)fd;
326			void *item;
327	twoaday	69	const char keyid=NULL, pass;
328	werner	36	DWORD n;
329	twoaday	77	int rc = 0;
330	werner	36
331	twoaday	77	if (!c) {
332			log_debug ("passphrase_cb: error '!c'\r\n");
333	werner	36	return gpg_error (GPG_ERR_INV_ARG);
334	twoaday	77	}
335	werner	36	c->bad_pwd = prev_was_bad? 1 : 0;
336			if (prev_was_bad && !c->cancel) {
337			if (c->pwd)
338			burn_passphrase (&c->pwd);
339			agent_del_cache (c->keyid);
340			c->pwd_init = 1;
341			}
342
343			if (passphrase_info) {
344			if (strlen (passphrase_info) < 16 &&
345			!strstr (passphrase_info, "OPENPGP")) {
346			/* assume symetric encryption. */
347	twoaday	69	int pos=2;
348	werner	36	c->sym.sym_algo = atoi (passphrase_info);
349			if (c->sym.sym_algo > 9)
350	twoaday	69	pos++;
351	werner	36	/* XXX: be more strict. */
352	twoaday	69	c->sym.s2k_mode = atoi (passphrase_info+pos);
353			c->sym.s2k_hash = atoi (passphrase_info+pos+2);
354	werner	36	}
355
356			keyid = parse_gpg_keyid (passphrase_info);
357	twoaday	77	pass = agent_get_cache (keyid+8, &item);
358	werner	36	if (pass) {
359			agent_unlock_cache_entry (&item);
360			c->pwd_init = 0;
361			if (!WriteFile (hd, pass, strlen (pass), &n, NULL))
362			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
363			if (!WriteFile (hd, "\n", 1, &n, NULL))
364			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
365			return 0;
366			}
367			}
368
369			if (c->pwd_init) {
370			if (keyid && strlen (keyid) == 16)
371			strcpy (c->keyid, keyid+8);
372
373			/* if @passphrase_info contains 'OPENPGP' we assume a smart card
374			has been used. */
375			if (strstr (passphrase_info, "OPENPGP")) {
376			const char *s=passphrase_info;
377			while (s && s && s != 'D')
378			s++;
379			_snprintf (c->info, sizeof c->info-1,
380			_("Please enter the PIN to unlock your secret card key\n"
381			"Card: %s"), extract_serial_no (s));
382			c->is_card = 1;
383			}
384			else if (uid_hint)
385			parse_gpg_description (uid_hint, passphrase_info,
386			c->info, sizeof c->info - 1);
387			if (c->gpg_cmd == GPG_CMD_DECRYPT) {
388			rc = DialogBoxParam (glob_hinst, (LPCSTR)IDD_WINPT_DECRYPT,
389			(HWND)c->hwnd, passphrase_callback_proc,
390			(LPARAM)c);
391			}
392			else if (c->gpg_cmd == GPG_CMD_SIGN) {
393			rc = DialogBoxParam (glob_hinst, (LPCSTR)IDD_WINPT_DECRYPT_SIGN,
394			(HWND)c->hwnd, passphrase_callback_proc,
395			(LPARAM)c);
396			}
397			if (rc == -1) {
398			if (!WriteFile (hd, "\n", 1, &n, NULL))
399			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
400			return 0;
401			}
402			c->pwd_init = 0;
403			}
404			if (c->cancel) {
405			if (!WriteFile (hd, "\n", 1, &n, NULL))
406			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
407			return 0;
408			}
409
410	twoaday	77	if (!WriteFile (hd, c->pwd, strlen (c->pwd), &n, NULL))
411			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
412			if (!WriteFile (hd, "\n", 1, &n, NULL))
413			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
414	werner	36	return 0;
415			}
416
417
418			/* Initialize the given passphrase callback @cb with the
419			used gpgme context @ctx, the command @cmd and a title
420			@title for the dialog. */
421			void
422			set_gpg_passphrase_cb (passphrase_cb_s *cb, gpgme_ctx_t ctx,
423			int cmd, HWND hwnd, const char *title)
424			{
425			memset (cb, 0, sizeof *cb);
426			cb->gpg_cmd = cmd;
427			cb->bad_pwd = 0;
428			cb->is_card = 0;
429			cb->cancel = 0;
430			cb->hwnd = hwnd;
431			cb->pwd_init = 1;
432			free_if_alloc (cb->title);
433			cb->title = m_strdup (title);
434			if (!cb->title)
435			BUG (NULL);
436			gpgme_set_passphrase_cb (ctx, passphrase_cb, cb);
437			cb->gpg = ctx;
438			}
439
440
441			/* Release a passphrase callback @ctx. */
442			void
443			release_gpg_passphrase_cb (passphrase_cb_s *ctx)
444			{
445			gpgme_recipient_t r, n;
446
447			if (!ctx)
448			return;
449			sfree_if_alloc (ctx->pwd);
450			free_if_alloc (ctx->title);
451			r = ctx->recipients;
452			while (r) {
453			n = r->next;
454			safe_free (r->keyid);
455			safe_free (r);
456			r = n;
457			}
458			}
459
460
461			/* Simple check to measure passphrase (@pass) quality.
462			Return value: 0 on success. */
463			int
464			check_passwd_quality (const char *pass, int strict)
465			{
466			int i, nd=0, nc=0, n;
467
468			n = strlen (pass);
469			if (n < 8)
470			return -1;
471
472			for (i=0; i < n; i++) {
473			if (isdigit (pass[i]))
474			nd++;
475			if (isalpha (pass[i]))
476			nc++;
477			}
478
479			/* check that the passphrase contains letters and numbers. */
480			if (nd == n \|\| nc == n)
481			return -1;
482
483			return 0;
484			}