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_recipient_t recip=NULL, r;
    winpt_key_s key;
    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"));
        SetWindowText (dlg, c->title);
        if (c->gpg_cmd == GPG_CMD_DECRYPT) {
            SetDlgItemText (dlg, IDC_DECRYPT_HIDE, _("&Hide Typing"));
            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) {
                memset (&key, 0, sizeof (key));
                if (!winpt_get_pubkey (r->keyid, &key)) {
                    gpgme_user_id_t u = key.ctx->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);
                winpt_release_pubkey (&key);
            }
        }
        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 {
                    char *p = new char[n+2];
                    if (!p)
                        BUG (NULL);
                    /* Get the passphrase and convert it utf8.
                       This does not just the us-ascii charset. */
                    SafeGetDlgItemText (dlg, item_ctrl_id (c->gpg_cmd), p, n+1);
                    c->pwd = native_to_utf8 (p);
                    sfree_if_alloc (p);
                }
                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 || !c->pwd) {
        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);
    gpgme_set_passphrase_cb (ctx, passphrase_cb, cb);
    cb->gpg = ctx;
}


/* Release the gpg recipient list. */
void
release_gpg_recipients (gpgme_recipient_t *recipients)
{
    gpgme_recipient_t r, n;

    r = *recipients;
    while (r != NULL) {
        n = r->next;
        safe_free (r->keyid);
        safe_free (r);
        r = n;
    }
    *recipients = NULL;
}


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


/* 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	twoaday	69	gpgme_recipient_t recip=NULL, r;
74	twoaday	217	winpt_key_s key;
75	twoaday	69	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	werner	36	SetWindowText (dlg, c->title);
95			if (c->gpg_cmd == GPG_CMD_DECRYPT) {
96	twoaday	214	SetDlgItemText (dlg, IDC_DECRYPT_HIDE, _("&Hide Typing"));
97	werner	36	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	twoaday	217	memset (&key, 0, sizeof (key));
119			if (!winpt_get_pubkey (r->keyid, &key)) {
120			gpgme_user_id_t u = key.ctx->uids;
121	twoaday	160
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	twoaday	217	winpt_release_pubkey (&key);
148	werner	36	}
149			}
150			else if (c->gpg_cmd == GPG_CMD_DECRYPT)
151			EnableWindow (GetDlgItem (dlg, IDC_DECRYPT_LIST), FALSE);
152			SetDlgItemText (dlg, c->gpg_cmd == GPG_CMD_DECRYPT?
153			IDC_DECRYPT_PWDINFO : IDC_DECRYPT_SIGN_PWDINFO,
154			c->bad_pwd? _("Bad passphrase; Enter passphrase again") :
155			_("Please enter your passphrase"));
156			if (c->gpg_cmd == GPG_CMD_DECRYPT) {
157			SetFocus (GetDlgItem (dlg, IDC_DECRYPT_PWD));
158			if (res && !res->recipients) {
159			const char *s = _("Symmetric encryption.\n"
160			"%s encrypted data.");
161			const char *alg = get_symkey_algo (c->sym.sym_algo);
162			info = new char[strlen (s) + strlen (alg) + 2];
163			if (!info)
164			BUG (NULL);
165			sprintf (info, s, alg);
166			SetDlgItemText (dlg, IDC_DECRYPT_MSG, info);
167			free_if_alloc (info);
168			}
169			else
170	twoaday	205	SetDlgItemText (dlg, IDC_DECRYPT_MSG, c->info);
171	werner	36	}
172			else {
173	twoaday	204	SetFocus (GetDlgItem (dlg, IDC_DECRYPT_SIGN_PWD));
174	twoaday	205	SetDlgItemText (dlg, IDC_DECRYPT_SIGN_MSG, c->info);
175	werner	36	}
176			center_window (dlg, NULL);
177			SetForegroundWindow (dlg);
178			return FALSE;
179
180			case WM_SYSCOMMAND:
181			if (LOWORD (wparam) == SC_CLOSE) {
182			SetDlgItemText (dlg, item_ctrl_id (c->gpg_cmd), "");
183			c->cancel = 1;
184			EndDialog (dlg, TRUE);
185			}
186			break;
187
188			case WM_COMMAND:
189			switch (HIWORD (wparam)) {
190			case BN_CLICKED:
191			if (LOWORD (wparam) == IDC_DECRYPT_HIDE
192			\|\| LOWORD (wparam) == IDC_DECRYPT_SIGN_HIDE) {
193			HWND hwnd;
194			int hide = IsDlgButtonChecked (dlg, item_ctrl_id2 (c->gpg_cmd));
195			hwnd = GetDlgItem (dlg, item_ctrl_id (c->gpg_cmd));
196			SendMessage (hwnd, EM_SETPASSWORDCHAR, hide? '*' : 0, 0);
197			SetFocus (hwnd);
198			}
199			}
200
201			switch (LOWORD (wparam)) {
202			case IDOK:
203			/* XXX: the item is even cached when the passphrase is not
204			correct, which means that the user needs to delete all
205			cached entries to continue. */
206			if (c->pwd)
207			burn_passphrase (&c->pwd);
208			n = item_get_text_length (dlg, item_ctrl_id (c->gpg_cmd));
209			if (!n) {
210			c->pwd = new char[2];
211			if (!c->pwd)
212			BUG (NULL);
213			strcpy (c->pwd, "");
214			}
215			else {
216	twoaday	229	char *p = new char[n+2];
217			if (!p)
218	werner	36	BUG (NULL);
219	twoaday	229	/* Get the passphrase and convert it utf8.
220			This does not just the us-ascii charset. */
221			SafeGetDlgItemText (dlg, item_ctrl_id (c->gpg_cmd), p, n+1);
222			c->pwd = native_to_utf8 (p);
223			sfree_if_alloc (p);
224	werner	36	}
225			res = gpgme_op_decrypt_result (c->gpg);
226			if (!res)
227	twoaday	77	res_sig = gpgme_op_sign_result (c->gpg);
228			if (reg_prefs.cache_time > 0 && !c->is_card &&
229			(res \|\| res_sig)) {
230			if (agent_get_cache (c->keyid, &item))
231	werner	36	agent_unlock_cache_entry (&item);
232	twoaday	77	else
233	werner	36	agent_put_cache (c->keyid, c->pwd, reg_prefs.cache_time);
234			}
235			c->cancel = 0;
236			EndDialog (dlg, TRUE);
237			return TRUE;
238
239			case IDCANCEL:
240			SetDlgItemText (dlg, item_ctrl_id (c->gpg_cmd), "");
241			c->cancel = 1;
242			EndDialog (dlg, FALSE);
243			return FALSE;
244			}
245			break;
246			}
247
248			return FALSE;
249			}
250
251
252			/* Extract the main keyid from @pass_info.
253			Return value: long main keyid or NULL for an error. */
254			static const char*
255			parse_gpg_keyid (const char *pass_info)
256			{
257			static char keyid[16+1];
258
259			/* XXX: check for leading alpha-chars? */
260	twoaday	77	if (strlen (pass_info) < 16) {
261			log_debug ("parse_gpg_keyid: error '%s'\r\n", pass_info);
262	werner	36	return NULL;
263	twoaday	77	}
264	werner	36	/* the format of the desc buffer looks like this:
265			request_keyid[16] main_keyid[16] keytype[1] keylength[4]
266			we use the main keyid to use only one cache entry. */
267			strncpy (keyid, pass_info+17, 16);
268			keyid[16] = 0;
269			return keyid;
270			}
271
272
273			/* Parse the information in @uid_hint and @pass_info to generate
274			a input message for the user in @desc. */
275			static int
276			parse_gpg_description (const char uid_hint, const char pass_info,
277			char *desc, int size)
278			{
279			gpgme_pubkey_algo_t algo;
280			char usedkey[16+1];
281			char mainkey[16+1];
282	twoaday	205	char p, uid;
283	werner	36	int n=0;
284
285	twoaday	69	algo = (gpgme_pubkey_algo_t)0;
286	werner	36	/* Each uid_hint contains a long key-ID so it is at least 16 bytes. */
287			if (strlen (uid_hint) < 17) {
288			*desc = 0;
289	twoaday	77	log_debug ("parse_gpg_description: error '%s'\r\n", uid_hint);
290	werner	36	return -1;
291			}
292
293			while (p = strsep ((char**)&pass_info, " ")) {
294			switch (n++) {
295			case 0: strncpy (mainkey, p, 16); mainkey[16] = 0; break;
296			case 1: strncpy (usedkey, p, 16); usedkey[16] = 0; break;
297			case 2: algo = (gpgme_pubkey_algo_t)atol (p); break;
298			}
299			}
300			uid_hint += 16; /* skip keyid */
301			uid_hint += 1; /* space */
302
303	twoaday	205	uid = utf8_to_native (uid_hint);
304	werner	36	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 (main key ID %s)\n"),
309	twoaday	205	uid, get_key_pubalgo (algo), usedkey+8, mainkey+8);
310	werner	36	else if (!strcmp (usedkey, mainkey))
311			_snprintf (desc, size-1,
312			_("You need a passphrase to unlock the secret key for\n"
313			"user: \"%s\"\n"
314			"%s key, ID %s\n"),
315	twoaday	205	uid, get_key_pubalgo (algo), usedkey+8);
316			safe_free (uid);
317	werner	36	return 0;
318			}
319
320
321			/* Extract the serial number from the card ID @id and return it. */
322			const char*
323			extract_serial_no (const char *id)
324			{
325			static char buf[8];
326			char *p;
327
328			p = strchr (id, '/');
329	twoaday	77	if (!p) {
330			log_debug ("extract_serial_no: error '%s'\r\n", id);
331	werner	36	return NULL;
332	twoaday	77	}
333	werner	36	strncpy (buf, id+(p-id)-6, 6);
334			return buf;
335			}
336
337
338			/* Passphrase callback with the ability to support caching. */
339			gpgme_error_t
340			passphrase_cb (void hook, const char uid_hint,
341			const char *passphrase_info,
342			int prev_was_bad, int fd)
343			{
344			passphrase_cb_s c = (passphrase_cb_s)hook;
345			HANDLE hd = (HANDLE)fd;
346			void *item;
347	twoaday	69	const char keyid=NULL, pass;
348	werner	36	DWORD n;
349	twoaday	77	int rc = 0;
350	werner	36
351	twoaday	77	if (!c) {
352			log_debug ("passphrase_cb: error '!c'\r\n");
353	werner	36	return gpg_error (GPG_ERR_INV_ARG);
354	twoaday	77	}
355	werner	36	c->bad_pwd = prev_was_bad? 1 : 0;
356			if (prev_was_bad && !c->cancel) {
357			if (c->pwd)
358			burn_passphrase (&c->pwd);
359			agent_del_cache (c->keyid);
360			c->pwd_init = 1;
361			}
362
363			if (passphrase_info) {
364			if (strlen (passphrase_info) < 16 &&
365			!strstr (passphrase_info, "OPENPGP")) {
366			/* assume symetric encryption. */
367	twoaday	69	int pos=2;
368	werner	36	c->sym.sym_algo = atoi (passphrase_info);
369			if (c->sym.sym_algo > 9)
370	twoaday	69	pos++;
371	werner	36	/* XXX: be more strict. */
372	twoaday	69	c->sym.s2k_mode = atoi (passphrase_info+pos);
373			c->sym.s2k_hash = atoi (passphrase_info+pos+2);
374	werner	36	}
375
376			keyid = parse_gpg_keyid (passphrase_info);
377	twoaday	77	pass = agent_get_cache (keyid+8, &item);
378	werner	36	if (pass) {
379			agent_unlock_cache_entry (&item);
380			c->pwd_init = 0;
381			if (!WriteFile (hd, pass, strlen (pass), &n, NULL))
382			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
383			if (!WriteFile (hd, "\n", 1, &n, NULL))
384			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
385			return 0;
386			}
387			}
388
389			if (c->pwd_init) {
390			if (keyid && strlen (keyid) == 16)
391			strcpy (c->keyid, keyid+8);
392
393			/* if @passphrase_info contains 'OPENPGP' we assume a smart card
394			has been used. */
395			if (strstr (passphrase_info, "OPENPGP")) {
396			const char *s=passphrase_info;
397			while (s && s && s != 'D')
398			s++;
399			_snprintf (c->info, sizeof c->info-1,
400			_("Please enter the PIN to unlock your secret card key\n"
401			"Card: %s"), extract_serial_no (s));
402			c->is_card = 1;
403			}
404			else if (uid_hint)
405			parse_gpg_description (uid_hint, passphrase_info,
406	twoaday	181	c->info, sizeof (c->info) - 1);
407	werner	36	if (c->gpg_cmd == GPG_CMD_DECRYPT) {
408			rc = DialogBoxParam (glob_hinst, (LPCSTR)IDD_WINPT_DECRYPT,
409			(HWND)c->hwnd, passphrase_callback_proc,
410			(LPARAM)c);
411			}
412			else if (c->gpg_cmd == GPG_CMD_SIGN) {
413			rc = DialogBoxParam (glob_hinst, (LPCSTR)IDD_WINPT_DECRYPT_SIGN,
414			(HWND)c->hwnd, passphrase_callback_proc,
415			(LPARAM)c);
416			}
417			if (rc == -1) {
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			c->pwd_init = 0;
423			}
424	twoaday	214	if (c->cancel \|\| !c->pwd) {
425	werner	36	if (!WriteFile (hd, "\n", 1, &n, NULL))
426			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
427			return 0;
428			}
429
430	twoaday	77	if (!WriteFile (hd, c->pwd, strlen (c->pwd), &n, NULL))
431			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
432			if (!WriteFile (hd, "\n", 1, &n, NULL))
433			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
434	werner	36	return 0;
435			}
436
437
438			/* Initialize the given passphrase callback @cb with the
439			used gpgme context @ctx, the command @cmd and a title
440			@title for the dialog. */
441			void
442			set_gpg_passphrase_cb (passphrase_cb_s *cb, gpgme_ctx_t ctx,
443			int cmd, HWND hwnd, const char *title)
444			{
445			memset (cb, 0, sizeof *cb);
446			cb->gpg_cmd = cmd;
447			cb->bad_pwd = 0;
448			cb->is_card = 0;
449			cb->cancel = 0;
450			cb->hwnd = hwnd;
451			cb->pwd_init = 1;
452			free_if_alloc (cb->title);
453			cb->title = m_strdup (title);
454			gpgme_set_passphrase_cb (ctx, passphrase_cb, cb);
455			cb->gpg = ctx;
456			}
457
458
459	twoaday	214	/* Release the gpg recipient list. */
460	werner	36	void
461	twoaday	214	release_gpg_recipients (gpgme_recipient_t *recipients)
462	werner	36	{
463			gpgme_recipient_t r, n;
464
465	twoaday	214	r = *recipients;
466			while (r != NULL) {
467	werner	36	n = r->next;
468			safe_free (r->keyid);
469			safe_free (r);
470			r = n;
471			}
472	twoaday	214	*recipients = NULL;
473	werner	36	}
474
475
476	twoaday	214
477			/* Release a passphrase callback @ctx. */
478			void
479			release_gpg_passphrase_cb (passphrase_cb_s *ctx)
480			{
481			if (!ctx)
482			return;
483			sfree_if_alloc (ctx->pwd);
484			free_if_alloc (ctx->title);
485			release_gpg_recipients (&ctx->recipients);
486			}
487
488
489	werner	36	/* Simple check to measure passphrase (@pass) quality.
490			Return value: 0 on success. */
491			int
492			check_passwd_quality (const char *pass, int strict)
493			{
494			int i, nd=0, nc=0, n;
495
496			n = strlen (pass);
497			if (n < 8)
498			return -1;
499
500			for (i=0; i < n; i++) {
501			if (isdigit (pass[i]))
502			nd++;
503			if (isalpha (pass[i]))
504			nc++;
505			}
506
507			/* check that the passphrase contains letters and numbers. */
508			if (nd == n \|\| nc == n)
509			return -1;
510
511			return 0;
512			}