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"
#include "wptUTF8.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 (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);
        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, *uid;
    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_native (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);
    safe_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	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	twoaday	205	#include "wptUTF8.h"
43	werner	36
44			const char* get_symkey_algo (int algo);
45
46	twoaday	181	#define item_ctrl_id(cmd) \
47	werner	36	((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	twoaday	204	void ListBox_AddString_utf8 (HWND lb, const char *txt);
54
55	werner	36	/* Overwrite passphrase and free memory. */
56			static void
57			burn_passphrase (char **pwd)
58			{
59			char pass = pwd;
60			wipememory (pass, strlen (pass));
61			delete []pass;
62			*pwd = NULL;
63			}
64
65
66			/* Dialog procedure for the passphrase callback. */
67			static BOOL CALLBACK
68			passphrase_callback_proc (HWND dlg, UINT msg, WPARAM wparam, LPARAM lparam)
69			{
70	twoaday	77	static passphrase_cb_s *c;
71			gpgme_decrypt_result_t res=NULL;
72			gpgme_sign_result_t res_sig=NULL;
73	werner	36	gpgme_key_t key;
74	twoaday	69	gpgme_recipient_t recip=NULL, r;
75			void *item;
76	werner	36	const char *id;
77			char *info;
78			int n;
79
80			switch (msg) {
81	twoaday	181	case WM_ACTIVATE:
82			safe_edit_control_init (dlg, item_ctrl_id (c->gpg_cmd));
83			break;
84
85			case WM_DESTROY:
86			safe_edit_control_free (dlg, item_ctrl_id (c->gpg_cmd));
87			break;
88
89	werner	36	case WM_INITDIALOG:
90			c = (passphrase_cb_s *)lparam;
91			if (!c)
92			BUG (0);
93	twoaday	105	SetDlgItemText (dlg, IDCANCEL, _("&Cancel"));
94	twoaday	85	SetDlgItemText (dlg, IDC_DECRYPT_HIDE, _("&Hide Typing"));
95	werner	36	SetWindowText (dlg, c->title);
96			if (c->gpg_cmd == GPG_CMD_DECRYPT) {
97			SetDlgItemText (dlg, IDC_DECRYPT_LISTINF,
98			_("Encrypted with the following public key(s)"));
99			CheckDlgButton (dlg, IDC_DECRYPT_HIDE, BST_CHECKED);
100			}
101	twoaday	95	else if (c->gpg_cmd == GPG_CMD_SIGN) {
102			SetDlgItemText (dlg, IDC_DECRYPT_SIGN_HIDE, _("&Hide Typing"));
103	werner	36	CheckDlgButton (dlg, IDC_DECRYPT_SIGN_HIDE, BST_CHECKED);
104	twoaday	95	}
105	twoaday	179	/* Because it depends on the order the keys are stored in the
106			keyring whether res->recipients is complete or not, we also
107			support that the recipients were externally extracted and then
108			we use this list. */
109	werner	36	if (c->recipients)
110			recip = c->recipients; /* recipients were already extracted. */
111			else {
112			res = gpgme_op_decrypt_result (c->gpg);
113			if (res && res->recipients)
114			recip = res->recipients;
115			}
116			if (recip != NULL && c->gpg_cmd == GPG_CMD_DECRYPT) {
117	twoaday	179	for (r = recip; r; r = r->next) {
118	werner	36	get_pubkey (r->keyid, &key);
119			if (key) {
120	twoaday	160	gpgme_user_id_t u = key->uids;
121
122			id = u->name;
123	werner	36	if (!id)
124			id = _("Invalid User ID");
125	twoaday	204	n = 32+strlen (id)+1+4+strlen (r->keyid)+1;
126	twoaday	160	if (u->email)
127			n += strlen (u->email)+1;
128			info = new char [n+1];
129	werner	36	if (!info)
130			BUG (NULL);
131	twoaday	160	if (!u->email \|\| strlen (u->email) < 1)
132	twoaday	204	sprintf (info, "%s (%s, 0x%s)", id,
133	twoaday	160	get_key_pubalgo (r->pubkey_algo), r->keyid+8);
134			else
135	twoaday	204	sprintf (info, "%s <%s> (%s, 0x%s)", id, u->email,
136	twoaday	160	get_key_pubalgo (r->pubkey_algo), r->keyid+8);
137	werner	36	}
138			else {
139			info = new char [32 + strlen (r->keyid)+1 + 4];
140			if (!info)
141			BUG (NULL);
142			sprintf (info, _("Unknown key ID (%s, 0x%s)"),
143			get_key_pubalgo (r->pubkey_algo), r->keyid+8);
144			}
145	twoaday	204	ListBox_AddString_utf8 (GetDlgItem (dlg, IDC_DECRYPT_LIST), info);
146	werner	36	free_if_alloc (info);
147			}
148			}
149			else if (c->gpg_cmd == GPG_CMD_DECRYPT)
150			EnableWindow (GetDlgItem (dlg, IDC_DECRYPT_LIST), FALSE);
151			SetDlgItemText (dlg, c->gpg_cmd == GPG_CMD_DECRYPT?
152			IDC_DECRYPT_PWDINFO : IDC_DECRYPT_SIGN_PWDINFO,
153			c->bad_pwd? _("Bad passphrase; Enter passphrase again") :
154			_("Please enter your passphrase"));
155			if (c->gpg_cmd == GPG_CMD_DECRYPT) {
156			SetFocus (GetDlgItem (dlg, IDC_DECRYPT_PWD));
157			if (res && !res->recipients) {
158			const char *s = _("Symmetric encryption.\n"
159			"%s encrypted data.");
160			const char *alg = get_symkey_algo (c->sym.sym_algo);
161			info = new char[strlen (s) + strlen (alg) + 2];
162			if (!info)
163			BUG (NULL);
164			sprintf (info, s, alg);
165			SetDlgItemText (dlg, IDC_DECRYPT_MSG, info);
166			free_if_alloc (info);
167			}
168			else
169	twoaday	205	SetDlgItemText (dlg, IDC_DECRYPT_MSG, c->info);
170	werner	36	}
171			else {
172	twoaday	204	SetFocus (GetDlgItem (dlg, IDC_DECRYPT_SIGN_PWD));
173	twoaday	205	SetDlgItemText (dlg, IDC_DECRYPT_SIGN_MSG, c->info);
174	werner	36	}
175			center_window (dlg, NULL);
176			SetForegroundWindow (dlg);
177			return FALSE;
178
179			case WM_SYSCOMMAND:
180			if (LOWORD (wparam) == SC_CLOSE) {
181			SetDlgItemText (dlg, item_ctrl_id (c->gpg_cmd), "");
182			c->cancel = 1;
183			EndDialog (dlg, TRUE);
184			}
185			break;
186
187			case WM_COMMAND:
188			switch (HIWORD (wparam)) {
189			case BN_CLICKED:
190			if (LOWORD (wparam) == IDC_DECRYPT_HIDE
191			\|\| LOWORD (wparam) == IDC_DECRYPT_SIGN_HIDE) {
192			HWND hwnd;
193			int hide = IsDlgButtonChecked (dlg, item_ctrl_id2 (c->gpg_cmd));
194			hwnd = GetDlgItem (dlg, item_ctrl_id (c->gpg_cmd));
195			SendMessage (hwnd, EM_SETPASSWORDCHAR, hide? '*' : 0, 0);
196			SetFocus (hwnd);
197			}
198			}
199
200			switch (LOWORD (wparam)) {
201			case IDOK:
202			/* XXX: the item is even cached when the passphrase is not
203			correct, which means that the user needs to delete all
204			cached entries to continue. */
205			if (c->pwd)
206			burn_passphrase (&c->pwd);
207			n = item_get_text_length (dlg, item_ctrl_id (c->gpg_cmd));
208			if (!n) {
209			c->pwd = new char[2];
210			if (!c->pwd)
211			BUG (NULL);
212			strcpy (c->pwd, "");
213			}
214			else {
215			c->pwd = new char[n+2];
216			if (!c->pwd)
217			BUG (NULL);
218	twoaday	181	SafeGetDlgItemText (dlg, item_ctrl_id (c->gpg_cmd),
219			c->pwd, n+1);
220	werner	36	}
221			res = gpgme_op_decrypt_result (c->gpg);
222			if (!res)
223	twoaday	77	res_sig = gpgme_op_sign_result (c->gpg);
224			if (reg_prefs.cache_time > 0 && !c->is_card &&
225			(res \|\| res_sig)) {
226			if (agent_get_cache (c->keyid, &item))
227	werner	36	agent_unlock_cache_entry (&item);
228	twoaday	77	else
229	werner	36	agent_put_cache (c->keyid, c->pwd, reg_prefs.cache_time);
230			}
231			c->cancel = 0;
232			EndDialog (dlg, TRUE);
233			return TRUE;
234
235			case IDCANCEL:
236			SetDlgItemText (dlg, item_ctrl_id (c->gpg_cmd), "");
237			c->cancel = 1;
238			EndDialog (dlg, FALSE);
239			return FALSE;
240			}
241			break;
242			}
243
244			return FALSE;
245			}
246
247
248			/* Extract the main keyid from @pass_info.
249			Return value: long main keyid or NULL for an error. */
250			static const char*
251			parse_gpg_keyid (const char *pass_info)
252			{
253			static char keyid[16+1];
254
255			/* XXX: check for leading alpha-chars? */
256	twoaday	77	if (strlen (pass_info) < 16) {
257			log_debug ("parse_gpg_keyid: error '%s'\r\n", pass_info);
258	werner	36	return NULL;
259	twoaday	77	}
260	werner	36	/* the format of the desc buffer looks like this:
261			request_keyid[16] main_keyid[16] keytype[1] keylength[4]
262			we use the main keyid to use only one cache entry. */
263			strncpy (keyid, pass_info+17, 16);
264			keyid[16] = 0;
265			return keyid;
266			}
267
268
269			/* Parse the information in @uid_hint and @pass_info to generate
270			a input message for the user in @desc. */
271			static int
272			parse_gpg_description (const char uid_hint, const char pass_info,
273			char *desc, int size)
274			{
275			gpgme_pubkey_algo_t algo;
276			char usedkey[16+1];
277			char mainkey[16+1];
278	twoaday	205	char p, uid;
279	werner	36	int n=0;
280
281	twoaday	69	algo = (gpgme_pubkey_algo_t)0;
282	werner	36	/* Each uid_hint contains a long key-ID so it is at least 16 bytes. */
283			if (strlen (uid_hint) < 17) {
284			*desc = 0;
285	twoaday	77	log_debug ("parse_gpg_description: error '%s'\r\n", uid_hint);
286	werner	36	return -1;
287			}
288
289			while (p = strsep ((char**)&pass_info, " ")) {
290			switch (n++) {
291			case 0: strncpy (mainkey, p, 16); mainkey[16] = 0; break;
292			case 1: strncpy (usedkey, p, 16); usedkey[16] = 0; break;
293			case 2: algo = (gpgme_pubkey_algo_t)atol (p); break;
294			}
295			}
296			uid_hint += 16; /* skip keyid */
297			uid_hint += 1; /* space */
298
299	twoaday	205	uid = utf8_to_native (uid_hint);
300	werner	36	if (strcmp (usedkey, mainkey))
301			_snprintf (desc, size-1,
302			_("You need a passphrase to unlock the secret key for\n"
303			"user: \"%s\"\n"
304			"%s key, ID %s (main key ID %s)\n"),
305	twoaday	205	uid, get_key_pubalgo (algo), usedkey+8, mainkey+8);
306	werner	36	else if (!strcmp (usedkey, mainkey))
307			_snprintf (desc, size-1,
308			_("You need a passphrase to unlock the secret key for\n"
309			"user: \"%s\"\n"
310			"%s key, ID %s\n"),
311	twoaday	205	uid, get_key_pubalgo (algo), usedkey+8);
312			safe_free (uid);
313	werner	36	return 0;
314			}
315
316
317			/* Extract the serial number from the card ID @id and return it. */
318			const char*
319			extract_serial_no (const char *id)
320			{
321			static char buf[8];
322			char *p;
323
324			p = strchr (id, '/');
325	twoaday	77	if (!p) {
326			log_debug ("extract_serial_no: error '%s'\r\n", id);
327	werner	36	return NULL;
328	twoaday	77	}
329	werner	36	strncpy (buf, id+(p-id)-6, 6);
330			return buf;
331			}
332
333
334			/* Passphrase callback with the ability to support caching. */
335			gpgme_error_t
336			passphrase_cb (void hook, const char uid_hint,
337			const char *passphrase_info,
338			int prev_was_bad, int fd)
339			{
340			passphrase_cb_s c = (passphrase_cb_s)hook;
341			HANDLE hd = (HANDLE)fd;
342			void *item;
343	twoaday	69	const char keyid=NULL, pass;
344	werner	36	DWORD n;
345	twoaday	77	int rc = 0;
346	werner	36
347	twoaday	77	if (!c) {
348			log_debug ("passphrase_cb: error '!c'\r\n");
349	werner	36	return gpg_error (GPG_ERR_INV_ARG);
350	twoaday	77	}
351	werner	36	c->bad_pwd = prev_was_bad? 1 : 0;
352			if (prev_was_bad && !c->cancel) {
353			if (c->pwd)
354			burn_passphrase (&c->pwd);
355			agent_del_cache (c->keyid);
356			c->pwd_init = 1;
357			}
358
359			if (passphrase_info) {
360			if (strlen (passphrase_info) < 16 &&
361			!strstr (passphrase_info, "OPENPGP")) {
362			/* assume symetric encryption. */
363	twoaday	69	int pos=2;
364	werner	36	c->sym.sym_algo = atoi (passphrase_info);
365			if (c->sym.sym_algo > 9)
366	twoaday	69	pos++;
367	werner	36	/* XXX: be more strict. */
368	twoaday	69	c->sym.s2k_mode = atoi (passphrase_info+pos);
369			c->sym.s2k_hash = atoi (passphrase_info+pos+2);
370	werner	36	}
371
372			keyid = parse_gpg_keyid (passphrase_info);
373	twoaday	77	pass = agent_get_cache (keyid+8, &item);
374	werner	36	if (pass) {
375			agent_unlock_cache_entry (&item);
376			c->pwd_init = 0;
377			if (!WriteFile (hd, pass, strlen (pass), &n, NULL))
378			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
379			if (!WriteFile (hd, "\n", 1, &n, NULL))
380			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
381			return 0;
382			}
383			}
384
385			if (c->pwd_init) {
386			if (keyid && strlen (keyid) == 16)
387			strcpy (c->keyid, keyid+8);
388
389			/* if @passphrase_info contains 'OPENPGP' we assume a smart card
390			has been used. */
391			if (strstr (passphrase_info, "OPENPGP")) {
392			const char *s=passphrase_info;
393			while (s && s && s != 'D')
394			s++;
395			_snprintf (c->info, sizeof c->info-1,
396			_("Please enter the PIN to unlock your secret card key\n"
397			"Card: %s"), extract_serial_no (s));
398			c->is_card = 1;
399			}
400			else if (uid_hint)
401			parse_gpg_description (uid_hint, passphrase_info,
402	twoaday	181	c->info, sizeof (c->info) - 1);
403	werner	36	if (c->gpg_cmd == GPG_CMD_DECRYPT) {
404			rc = DialogBoxParam (glob_hinst, (LPCSTR)IDD_WINPT_DECRYPT,
405			(HWND)c->hwnd, passphrase_callback_proc,
406			(LPARAM)c);
407			}
408			else if (c->gpg_cmd == GPG_CMD_SIGN) {
409			rc = DialogBoxParam (glob_hinst, (LPCSTR)IDD_WINPT_DECRYPT_SIGN,
410			(HWND)c->hwnd, passphrase_callback_proc,
411			(LPARAM)c);
412			}
413			if (rc == -1) {
414			if (!WriteFile (hd, "\n", 1, &n, NULL))
415			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
416			return 0;
417			}
418			c->pwd_init = 0;
419			}
420			if (c->cancel) {
421			if (!WriteFile (hd, "\n", 1, &n, NULL))
422			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
423			return 0;
424			}
425
426	twoaday	77	if (!WriteFile (hd, c->pwd, strlen (c->pwd), &n, NULL))
427			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
428			if (!WriteFile (hd, "\n", 1, &n, NULL))
429			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
430	werner	36	return 0;
431			}
432
433
434			/* Initialize the given passphrase callback @cb with the
435			used gpgme context @ctx, the command @cmd and a title
436			@title for the dialog. */
437			void
438			set_gpg_passphrase_cb (passphrase_cb_s *cb, gpgme_ctx_t ctx,
439			int cmd, HWND hwnd, const char *title)
440			{
441			memset (cb, 0, sizeof *cb);
442			cb->gpg_cmd = cmd;
443			cb->bad_pwd = 0;
444			cb->is_card = 0;
445			cb->cancel = 0;
446			cb->hwnd = hwnd;
447			cb->pwd_init = 1;
448			free_if_alloc (cb->title);
449			cb->title = m_strdup (title);
450			if (!cb->title)
451			BUG (NULL);
452			gpgme_set_passphrase_cb (ctx, passphrase_cb, cb);
453			cb->gpg = ctx;
454			}
455
456
457			/* Release a passphrase callback @ctx. */
458			void
459			release_gpg_passphrase_cb (passphrase_cb_s *ctx)
460			{
461			gpgme_recipient_t r, n;
462
463			if (!ctx)
464			return;
465			sfree_if_alloc (ctx->pwd);
466			free_if_alloc (ctx->title);
467			r = ctx->recipients;
468			while (r) {
469			n = r->next;
470			safe_free (r->keyid);
471			safe_free (r);
472			r = n;
473			}
474			}
475
476
477			/* Simple check to measure passphrase (@pass) quality.
478			Return value: 0 on success. */
479			int
480			check_passwd_quality (const char *pass, int strict)
481			{
482			int i, nd=0, nc=0, n;
483
484			n = strlen (pass);
485			if (n < 8)
486			return -1;
487
488			for (i=0; i < n; i++) {
489			if (isdigit (pass[i]))
490			nd++;
491			if (isalpha (pass[i]))
492			nc++;
493			}
494
495			/* check that the passphrase contains letters and numbers. */
496			if (nd == n \|\| nc == n)
497			return -1;
498
499			return 0;
500			}