trunk/Src/wptPassphraseCB.cpp

/* wptPassphraseCB.cpp - GPGME Passphrase Callback
 *      Copyright (C) 2001, 2002-2006 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.
 */
#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"
#include "StringBuffer.h"


/* Return the control ID dependent on the mode (sign or decrypt). */
#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)

const char* get_symkey_algo (int algo);
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;
    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) {
            StringBuffer inf;

            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;
                    
                    inf = (u->name? u->name : _("Invalid User ID"));
                    if (u->email != NULL && strlen (u->email) > 1)
                        inf = inf + " <" + u->email + ">";
                    inf = inf + " (" + get_key_pubalgo (r->pubkey_algo);
                    inf = inf + ", 0x" + (r->keyid+8) + ")";
                }
                else {
                    inf = _("Unknown key ID");
                    inf = inf + " (" + get_key_pubalgo (r->pubkey_algo);
                    inf = inf + ", 0x" + (r->keyid+8) + ")";
                }
                ListBox_AddString_utf8 (GetDlgItem (dlg, IDC_DECRYPT_LIST),
                                        inf.getBuffer ());
                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) {
                StringBuffer sinf;

                sinf = _("Symmetric encryption.");
                sinf = sinf + "\n" + get_symkey_algo (c->sym.sym_algo);
                sinf = sinf + " " + _("encrypted data.");
                SetDlgItemText (dlg, IDC_DECRYPT_MSG, sinf.getBuffer ());
            }
            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_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 (!c->is_card && reg_prefs.cache_time > 0 && 
                    (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 TRUE;
            }
            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 user:\n"
                     "\"%s\"\n"
                     "%s key, ID 0x%s (main key ID 0x%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 user:\n"
                     "\"%s\"\n"
                     "%s key, ID 0x%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 "";
    }
    memset (buf, 0, sizeof (buf));
    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 no valid callback\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);
            log_debug ("passphrase_cb: could not create dialog box\n");
            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;

    /* A good passphrase should be at least 8 characters. */
    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	255	* Copyright (C) 2001, 2002-2006 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			#ifdef HAVE_CONFIG_H
18			#include <config.h>
19			#endif
20
21			#include <windows.h>
22			#include <ctype.h>
23
24	werner	47	#include "resource.h"
25	werner	36	#include "wptNLS.h"
26			#include "wptW32API.h"
27			#include "wptVersion.h"
28			#include "wptGPG.h"
29			#include "wptCommonCtl.h"
30			#include "wptContext.h"
31			#include "wptDlgs.h"
32			#include "wptErrors.h"
33			#include "wptTypes.h"
34	werner	48	#include "wptKeylist.h"
35	werner	36	#include "wptAgent.h"
36			#include "wptRegistry.h"
37	twoaday	205	#include "wptUTF8.h"
38	twoaday	278	#include "StringBuffer.h"
39	werner	36
40
41	twoaday	255	/* Return the control ID dependent on the mode (sign or decrypt). */
42	twoaday	181	#define item_ctrl_id(cmd) \
43	werner	36	((cmd) == GPG_CMD_DECRYPT? IDC_DECRYPT_PWD : IDC_DECRYPT_SIGN_PWD)
44
45			#define item_ctrl_id2(cmd) \
46			((cmd) == GPG_CMD_DECRYPT? IDC_DECRYPT_HIDE : IDC_DECRYPT_SIGN_HIDE)
47
48	twoaday	255	const char* get_symkey_algo (int algo);
49	twoaday	204	void ListBox_AddString_utf8 (HWND lb, const char *txt);
50
51	twoaday	255
52	werner	36	/* Overwrite passphrase and free memory. */
53			static void
54			burn_passphrase (char **pwd)
55			{
56			char pass = pwd;
57	twoaday	271
58	werner	36	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	twoaday	69	gpgme_recipient_t recip=NULL, r;
72	twoaday	217	winpt_key_s key;
73	twoaday	69	void *item;
74	werner	36	int n;
75
76			switch (msg) {
77	twoaday	181	case WM_ACTIVATE:
78			safe_edit_control_init (dlg, item_ctrl_id (c->gpg_cmd));
79			break;
80
81			case WM_DESTROY:
82			safe_edit_control_free (dlg, item_ctrl_id (c->gpg_cmd));
83			break;
84
85	werner	36	case WM_INITDIALOG:
86			c = (passphrase_cb_s *)lparam;
87			if (!c)
88			BUG (0);
89	twoaday	105	SetDlgItemText (dlg, IDCANCEL, _("&Cancel"));
90	werner	36	SetWindowText (dlg, c->title);
91			if (c->gpg_cmd == GPG_CMD_DECRYPT) {
92	twoaday	214	SetDlgItemText (dlg, IDC_DECRYPT_HIDE, _("&Hide Typing"));
93	werner	36	SetDlgItemText (dlg, IDC_DECRYPT_LISTINF,
94			_("Encrypted with the following public key(s)"));
95			CheckDlgButton (dlg, IDC_DECRYPT_HIDE, BST_CHECKED);
96			}
97	twoaday	95	else if (c->gpg_cmd == GPG_CMD_SIGN) {
98			SetDlgItemText (dlg, IDC_DECRYPT_SIGN_HIDE, _("&Hide Typing"));
99	werner	36	CheckDlgButton (dlg, IDC_DECRYPT_SIGN_HIDE, BST_CHECKED);
100	twoaday	95	}
101	twoaday	179	/* Because it depends on the order the keys are stored in the
102			keyring whether res->recipients is complete or not, we also
103			support that the recipients were externally extracted and then
104			we use this list. */
105	werner	36	if (c->recipients)
106			recip = c->recipients; /* recipients were already extracted. */
107			else {
108			res = gpgme_op_decrypt_result (c->gpg);
109			if (res && res->recipients)
110			recip = res->recipients;
111			}
112			if (recip != NULL && c->gpg_cmd == GPG_CMD_DECRYPT) {
113	twoaday	278	StringBuffer inf;
114
115	twoaday	179	for (r = recip; r; r = r->next) {
116	twoaday	217	memset (&key, 0, sizeof (key));
117			if (!winpt_get_pubkey (r->keyid, &key)) {
118			gpgme_user_id_t u = key.ctx->uids;
119	twoaday	278
120			inf = (u->name? u->name : _("Invalid User ID"));
121			if (u->email != NULL && strlen (u->email) > 1)
122			inf = inf + " <" + u->email + ">";
123			inf = inf + " (" + get_key_pubalgo (r->pubkey_algo);
124			inf = inf + ", 0x" + (r->keyid+8) + ")";
125	werner	36	}
126			else {
127	twoaday	278	inf = _("Unknown key ID");
128			inf = inf + " (" + get_key_pubalgo (r->pubkey_algo);
129			inf = inf + ", 0x" + (r->keyid+8) + ")";
130	werner	36	}
131	twoaday	278	ListBox_AddString_utf8 (GetDlgItem (dlg, IDC_DECRYPT_LIST),
132			inf.getBuffer ());
133	twoaday	217	winpt_release_pubkey (&key);
134	werner	36	}
135			}
136			else if (c->gpg_cmd == GPG_CMD_DECRYPT)
137			EnableWindow (GetDlgItem (dlg, IDC_DECRYPT_LIST), FALSE);
138			SetDlgItemText (dlg, c->gpg_cmd == GPG_CMD_DECRYPT?
139			IDC_DECRYPT_PWDINFO : IDC_DECRYPT_SIGN_PWDINFO,
140			c->bad_pwd? _("Bad passphrase; Enter passphrase again") :
141			_("Please enter your passphrase"));
142			if (c->gpg_cmd == GPG_CMD_DECRYPT) {
143			SetFocus (GetDlgItem (dlg, IDC_DECRYPT_PWD));
144			if (res && !res->recipients) {
145	twoaday	278	StringBuffer sinf;
146
147			sinf = _("Symmetric encryption.");
148			sinf = sinf + "\n" + get_symkey_algo (c->sym.sym_algo);
149			sinf = sinf + " " + _("encrypted data.");
150			SetDlgItemText (dlg, IDC_DECRYPT_MSG, sinf.getBuffer ());
151	werner	36	}
152			else
153	twoaday	205	SetDlgItemText (dlg, IDC_DECRYPT_MSG, c->info);
154	werner	36	}
155			else {
156	twoaday	204	SetFocus (GetDlgItem (dlg, IDC_DECRYPT_SIGN_PWD));
157	twoaday	205	SetDlgItemText (dlg, IDC_DECRYPT_SIGN_MSG, c->info);
158	werner	36	}
159			center_window (dlg, NULL);
160			SetForegroundWindow (dlg);
161			return FALSE;
162
163			case WM_COMMAND:
164			switch (HIWORD (wparam)) {
165			case BN_CLICKED:
166			if (LOWORD (wparam) == IDC_DECRYPT_HIDE
167			\|\| LOWORD (wparam) == IDC_DECRYPT_SIGN_HIDE) {
168			HWND hwnd;
169			int hide = IsDlgButtonChecked (dlg, item_ctrl_id2 (c->gpg_cmd));
170			hwnd = GetDlgItem (dlg, item_ctrl_id (c->gpg_cmd));
171			SendMessage (hwnd, EM_SETPASSWORDCHAR, hide? '*' : 0, 0);
172			SetFocus (hwnd);
173			}
174			}
175
176			switch (LOWORD (wparam)) {
177			case IDOK:
178			/* XXX: the item is even cached when the passphrase is not
179			correct, which means that the user needs to delete all
180			cached entries to continue. */
181			if (c->pwd)
182			burn_passphrase (&c->pwd);
183			n = item_get_text_length (dlg, item_ctrl_id (c->gpg_cmd));
184			if (!n) {
185			c->pwd = new char[2];
186			if (!c->pwd)
187			BUG (NULL);
188			strcpy (c->pwd, "");
189			}
190			else {
191	twoaday	229	char *p = new char[n+2];
192			if (!p)
193	werner	36	BUG (NULL);
194	twoaday	229	/* Get the passphrase and convert it utf8.
195			This does not just the us-ascii charset. */
196			SafeGetDlgItemText (dlg, item_ctrl_id (c->gpg_cmd), p, n+1);
197			c->pwd = native_to_utf8 (p);
198			sfree_if_alloc (p);
199	werner	36	}
200			res = gpgme_op_decrypt_result (c->gpg);
201			if (!res)
202	twoaday	271	res_sig = gpgme_op_sign_result (c->gpg);
203	twoaday	255	if (!c->is_card && reg_prefs.cache_time > 0 &&
204	twoaday	77	(res \|\| res_sig)) {
205	twoaday	255	if (agent_get_cache (c->keyid, &item))
206	werner	36	agent_unlock_cache_entry (&item);
207	twoaday	77	else
208	werner	36	agent_put_cache (c->keyid, c->pwd, reg_prefs.cache_time);
209			}
210			c->cancel = 0;
211			EndDialog (dlg, TRUE);
212			return TRUE;
213
214			case IDCANCEL:
215			SetDlgItemText (dlg, item_ctrl_id (c->gpg_cmd), "");
216			c->cancel = 1;
217			EndDialog (dlg, FALSE);
218	twoaday	271	return TRUE;
219	werner	36	}
220			break;
221			}
222
223			return FALSE;
224			}
225
226
227			/* Extract the main keyid from @pass_info.
228			Return value: long main keyid or NULL for an error. */
229			static const char*
230			parse_gpg_keyid (const char *pass_info)
231			{
232			static char keyid[16+1];
233
234			/* XXX: check for leading alpha-chars? */
235	twoaday	77	if (strlen (pass_info) < 16) {
236			log_debug ("parse_gpg_keyid: error '%s'\r\n", pass_info);
237	werner	36	return NULL;
238	twoaday	77	}
239	werner	36	/* the format of the desc buffer looks like this:
240			request_keyid[16] main_keyid[16] keytype[1] keylength[4]
241			we use the main keyid to use only one cache entry. */
242			strncpy (keyid, pass_info+17, 16);
243			keyid[16] = 0;
244			return keyid;
245			}
246
247
248			/* Parse the information in @uid_hint and @pass_info to generate
249			a input message for the user in @desc. */
250			static int
251			parse_gpg_description (const char uid_hint, const char pass_info,
252			char *desc, int size)
253			{
254			gpgme_pubkey_algo_t algo;
255			char usedkey[16+1];
256			char mainkey[16+1];
257	twoaday	205	char p, uid;
258	werner	36	int n=0;
259
260	twoaday	69	algo = (gpgme_pubkey_algo_t)0;
261	werner	36	/* Each uid_hint contains a long key-ID so it is at least 16 bytes. */
262			if (strlen (uid_hint) < 17) {
263			*desc = 0;
264	twoaday	77	log_debug ("parse_gpg_description: error '%s'\r\n", uid_hint);
265	werner	36	return -1;
266			}
267
268			while (p = strsep ((char**)&pass_info, " ")) {
269			switch (n++) {
270			case 0: strncpy (mainkey, p, 16); mainkey[16] = 0; break;
271			case 1: strncpy (usedkey, p, 16); usedkey[16] = 0; break;
272			case 2: algo = (gpgme_pubkey_algo_t)atol (p); break;
273			}
274			}
275			uid_hint += 16; /* skip keyid */
276			uid_hint += 1; /* space */
277
278	twoaday	205	uid = utf8_to_native (uid_hint);
279	werner	36	if (strcmp (usedkey, mainkey))
280			_snprintf (desc, size-1,
281	twoaday	255	_("You need a passphrase to unlock the secret key for user:\n"
282			"\"%s\"\n"
283			"%s key, ID 0x%s (main key ID 0x%s)\n"),
284	twoaday	205	uid, get_key_pubalgo (algo), usedkey+8, mainkey+8);
285	werner	36	else if (!strcmp (usedkey, mainkey))
286			_snprintf (desc, size-1,
287	twoaday	255	_("You need a passphrase to unlock the secret key for user:\n"
288			"\"%s\"\n"
289			"%s key, ID 0x%s\n"),
290	twoaday	205	uid, get_key_pubalgo (algo), usedkey+8);
291			safe_free (uid);
292	werner	36	return 0;
293			}
294
295
296			/* Extract the serial number from the card ID @id and return it. */
297			const char*
298			extract_serial_no (const char *id)
299			{
300			static char buf[8];
301			char *p;
302
303			p = strchr (id, '/');
304	twoaday	77	if (!p) {
305			log_debug ("extract_serial_no: error '%s'\r\n", id);
306	twoaday	260	return "";
307	twoaday	77	}
308	twoaday	260	memset (buf, 0, sizeof (buf));
309	werner	36	strncpy (buf, id+(p-id)-6, 6);
310			return buf;
311			}
312
313
314			/* Passphrase callback with the ability to support caching. */
315			gpgme_error_t
316			passphrase_cb (void hook, const char uid_hint,
317			const char *passphrase_info,
318			int prev_was_bad, int fd)
319			{
320			passphrase_cb_s c = (passphrase_cb_s)hook;
321			HANDLE hd = (HANDLE)fd;
322			void *item;
323	twoaday	69	const char keyid=NULL, pass;
324	werner	36	DWORD n;
325	twoaday	77	int rc = 0;
326	werner	36
327	twoaday	77	if (!c) {
328	twoaday	271	log_debug ("passphrase_cb: error no valid callback\r\n");
329	werner	36	return gpg_error (GPG_ERR_INV_ARG);
330	twoaday	77	}
331	werner	36	c->bad_pwd = prev_was_bad? 1 : 0;
332			if (prev_was_bad && !c->cancel) {
333			if (c->pwd)
334			burn_passphrase (&c->pwd);
335			agent_del_cache (c->keyid);
336			c->pwd_init = 1;
337			}
338
339			if (passphrase_info) {
340			if (strlen (passphrase_info) < 16 &&
341			!strstr (passphrase_info, "OPENPGP")) {
342			/* assume symetric encryption. */
343	twoaday	69	int pos=2;
344	werner	36	c->sym.sym_algo = atoi (passphrase_info);
345			if (c->sym.sym_algo > 9)
346	twoaday	69	pos++;
347	werner	36	/* XXX: be more strict. */
348	twoaday	69	c->sym.s2k_mode = atoi (passphrase_info+pos);
349			c->sym.s2k_hash = atoi (passphrase_info+pos+2);
350	werner	36	}
351
352			keyid = parse_gpg_keyid (passphrase_info);
353	twoaday	77	pass = agent_get_cache (keyid+8, &item);
354	werner	36	if (pass) {
355			agent_unlock_cache_entry (&item);
356			c->pwd_init = 0;
357			if (!WriteFile (hd, pass, strlen (pass), &n, NULL))
358			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
359			if (!WriteFile (hd, "\n", 1, &n, NULL))
360			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
361			return 0;
362			}
363			}
364
365			if (c->pwd_init) {
366			if (keyid && strlen (keyid) == 16)
367			strcpy (c->keyid, keyid+8);
368
369			/* if @passphrase_info contains 'OPENPGP' we assume a smart card
370			has been used. */
371			if (strstr (passphrase_info, "OPENPGP")) {
372			const char *s=passphrase_info;
373			while (s && s && s != 'D')
374			s++;
375	twoaday	278	_snprintf (c->info, sizeof (c->info)-1,
376	werner	36	_("Please enter the PIN to unlock your secret card key\n"
377			"Card: %s"), extract_serial_no (s));
378			c->is_card = 1;
379			}
380			else if (uid_hint)
381			parse_gpg_description (uid_hint, passphrase_info,
382	twoaday	181	c->info, sizeof (c->info) - 1);
383	werner	36	if (c->gpg_cmd == GPG_CMD_DECRYPT) {
384			rc = DialogBoxParam (glob_hinst, (LPCSTR)IDD_WINPT_DECRYPT,
385			(HWND)c->hwnd, passphrase_callback_proc,
386			(LPARAM)c);
387			}
388			else if (c->gpg_cmd == GPG_CMD_SIGN) {
389			rc = DialogBoxParam (glob_hinst, (LPCSTR)IDD_WINPT_DECRYPT_SIGN,
390			(HWND)c->hwnd, passphrase_callback_proc,
391			(LPARAM)c);
392			}
393			if (rc == -1) {
394			if (!WriteFile (hd, "\n", 1, &n, NULL))
395			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
396	twoaday	271	log_debug ("passphrase_cb: could not create dialog box\n");
397	werner	36	return 0;
398			}
399			c->pwd_init = 0;
400			}
401	twoaday	214	if (c->cancel \|\| !c->pwd) {
402	werner	36	if (!WriteFile (hd, "\n", 1, &n, NULL))
403			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
404			return 0;
405			}
406
407	twoaday	77	if (!WriteFile (hd, c->pwd, strlen (c->pwd), &n, NULL))
408			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
409			if (!WriteFile (hd, "\n", 1, &n, NULL))
410			log_debug ("passphrase_cb: WriteFile() failed ec=%d\n", w32_errno);
411	werner	36	return 0;
412			}
413
414
415			/* Initialize the given passphrase callback @cb with the
416			used gpgme context @ctx, the command @cmd and a title
417			@title for the dialog. */
418			void
419			set_gpg_passphrase_cb (passphrase_cb_s *cb, gpgme_ctx_t ctx,
420			int cmd, HWND hwnd, const char *title)
421			{
422			memset (cb, 0, sizeof *cb);
423			cb->gpg_cmd = cmd;
424			cb->bad_pwd = 0;
425			cb->is_card = 0;
426			cb->cancel = 0;
427			cb->hwnd = hwnd;
428			cb->pwd_init = 1;
429			free_if_alloc (cb->title);
430			cb->title = m_strdup (title);
431			gpgme_set_passphrase_cb (ctx, passphrase_cb, cb);
432			cb->gpg = ctx;
433			}
434
435
436	twoaday	214	/* Release the gpg recipient list. */
437	werner	36	void
438	twoaday	214	release_gpg_recipients (gpgme_recipient_t *recipients)
439	werner	36	{
440			gpgme_recipient_t r, n;
441
442	twoaday	214	r = *recipients;
443			while (r != NULL) {
444	werner	36	n = r->next;
445			safe_free (r->keyid);
446			safe_free (r);
447			r = n;
448			}
449	twoaday	214	*recipients = NULL;
450	werner	36	}
451
452
453	twoaday	214
454			/* Release a passphrase callback @ctx. */
455			void
456			release_gpg_passphrase_cb (passphrase_cb_s *ctx)
457			{
458			if (!ctx)
459			return;
460			sfree_if_alloc (ctx->pwd);
461			free_if_alloc (ctx->title);
462			release_gpg_recipients (&ctx->recipients);
463			}
464
465
466	twoaday	271	/* _Simple_ check to measure passphrase (@pass) quality.
467	werner	36	Return value: 0 on success. */
468			int
469			check_passwd_quality (const char *pass, int strict)
470			{
471			int i, nd=0, nc=0, n;
472
473	twoaday	271	/* A good passphrase should be at least 8 characters. */
474	werner	36	n = strlen (pass);
475			if (n < 8)
476			return -1;
477
478			for (i=0; i < n; i++) {
479	twoaday	271	if (isdigit (pass[i]))
480	werner	36	nd++;
481	twoaday	271	if (isalpha (pass[i]))
482	werner	36	nc++;
483			}
484
485	twoaday	271	/* Check that the passphrase contains letters and numbers. */
486	werner	36	if (nd == n \|\| nc == n)
487			return -1;
488
489			return 0;
490			}