trunk/src/OECrypto.c

/* OECrypto.c - OE crypto functions
 *      Copyright (C) 2001, 2002, 2003, 2006 Timo Schulz
 *
 * This file is part of GPGOE.
 *
 * GPGOE is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation; either version 2.1 of the License, or
 * (at your option) any later version.
 * 
 * GPGOE 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 Lesser General Public License
 * along with GPGOE; 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 <assert.h>
#include <commctrl.h>

#include "resource.h"
#include "gpgme.h"
#include "GPGOE.h"


/* Valid OpenPGP message types. */
enum {
    PGP_MESSAGE     =  1,       
    PGP_CLEARSIG    =  2,       
    PGP_SIG         =  4,
    PGP_KEY         =  8,
};


/* Move the keyboard focus to the message window 
   to copy the text to the clipboard. */
static void
set_focus (HWND main)
{       
    HWND doc, mime, msg;

    doc = FindWindowEx (main, NULL, "ME_DocHost", NULL );
    mime = FindWindowEx (doc, NULL, "##MimeEdit_Server", NULL);
    msg = FindWindowEx (mime, NULL, "Internet Explorer_Server", NULL);

    AttachThreadInput (GetCurrentThreadId (),
                       GetWindowThreadProcessId (main, NULL),
                       TRUE);

    SetFocus (doc);
    SetFocus (mime);
    SetFocus (msg);

    AttachThreadInput (GetCurrentThreadId (),
                       GetWindowThreadProcessId (main, NULL),
                       FALSE);
}


/* Copy the message to the clipboard and then return the clipboard
   data (which is the message). */
static char*
window_get_message (HWND main_hwnd)
{
    set_focus (main_hwnd);
    SetForegroundWindow (main_hwnd);
    SendMessage (main_hwnd, WM_COMMAND, MAKEWPARAM (ID_OE_SELECTALL, 0), 0);
    SendMessage (main_hwnd, WM_COMMAND, MAKEWPARAM (ID_OE_COPY, 0), 0);

    /* even so SendMessage() should wait, we wait for safety reasons. */
    Sleep (200);
    return get_clip_text (NULL);
}


/* Paste the message given in @msg into the window @main_hwnd.
   To make sure all existing text is overwritten, "select all"
   is send to the window first. */
static void
window_set_message (HWND main_hwnd, const char *msg)
{   
    set_clip_text (NULL, msg, strlen (msg));
    set_focus (main_hwnd);
    SetForegroundWindow (main_hwnd);
    SendMessage (main_hwnd, WM_COMMAND, MAKEWPARAM (ID_OE_SELECTALL, 0), 0);
    SendMessage (main_hwnd, WM_COMMAND, MAKEWPARAM (ID_OE_PASTE, 0), 0);
}


/* Try to find the given recipient by key @key and
   return it (NULL in case of error). */
static recip_list_t
find_recipient (recip_list_t rset, gpgme_key_t key)
{
    recip_list_t n;
    gpgme_user_id_t u;

    for (n = rset; n; n = n->next) {
        for (u = key->uids; u; u = u->next) {
            if (u->email && strstr (u->email, n->addr))
                return n;
        }
    }
    return NULL;
}


/* Add recipient with address @addr and key @key to @rset. */
void
add_recipient (recip_list_t *rset, const char *addr, gpgme_key_t key)
{
    recip_list_t r, n;

    r = xcalloc (1, sizeof *r);
    r->addr = xstrdup (addr);
    r->key = key;
    if (!*rset)
        *rset = r;
    else {
        for (n=*rset; n->next; n=n->next)
            ;
        n->next = r;
    }
}


/* Release recipient list @rset. */
static void
release_recipient (recip_list_t rset)
{
    recip_list_t n;

    while (rset != NULL) {
        n = rset->next;
        if (rset->key)
            gpgme_key_release (rset->key);
        free_if_alloc (rset->addr);
        free_if_alloc (rset);
        rset = n;
    }
}


/* This functions converts the OE recipient fields to GPG compatible fields.
   Currently the function support the following 'From' styles:
   John Hacker <[email protected]>; [email protected]
   or Foo Bar <[email protected]>, [email protected].
   only the part between '<' '>' are added.
 */
static int
parse_recipients (plugin_ctx_t ctx, recip_list_t *rset, char *recpt)
{
    char *token, *p;
    int count = 0;
    char *p1, *p2;
    int n1, n2;

    assert (recpt && rset);
                
    token = strtok (recpt, ",;");
    while (token != NULL ) {
        if ((p1=strchr (token, '<')) && (p2=strchr (token, '>'))
            && strchr (token, '@')) {
            n1 = p1 - token + 1 ;
            n2 = p2 - token + 1;

            p = xcalloc (1, strlen (token) + 1);
            memcpy (p, token+n1, n2-n1-1);
            add_recipient (rset, p, NULL);
            count++;
            free_if_alloc (p);
        }
        else if (strchr (token, '@') && !strchr (token, ' ')) {
            p = xcalloc (1, strlen (token) + 1);
            memcpy (p, token, strlen (token));
            add_recipient (rset, p, NULL);
            count++;
            free_if_alloc (p);
        }
        token = strtok (NULL, ",;");
    }
    return count;
}


/* Fill in the key part of the recipient list @addrs if possible. */
static int
get_keys_from_addresses (recip_list_t addrs)
{
    gpgme_ctx_t ctx;
    gpgme_error_t err;
    gpgme_key_t pk;    
    recip_list_t n, fnd;
    char *p;
    int nkeys=0;
    DWORD len=0;

    for (n = addrs; n; n = n->next)
        len += strlen (n->addr) + 3;
    p = xcalloc (1, len + 1);
    for (n = addrs; n; n = n->next) {
        strcat (p, n->addr);
        strcat (p, " ");
    }

    err = gpgme_new (&ctx);
    if (!err)
        err = gpgme_op_keylist_start (ctx, p, 0);
    while (!err) {
        err = gpgme_op_keylist_next (ctx, &pk);
        if (err)
            break;
        /* do not add invalid keys. */
        if (pk->disabled || pk->expired || pk->revoked)
            continue;
        fnd = find_recipient (addrs, pk);
        if (fnd != NULL && pk->can_encrypt) {
            fnd->key = pk;
            nkeys++;
        }
    }

    gpgme_release (ctx);
    free_if_alloc (p);
    return nkeys;
}


/* Create gpgme input data object. If @encode is 1, use UTF8 conversion. */
gpgme_error_t
create_in_data (gpgme_data_t *in, const char *buf, int encode)
{
    gpgme_error_t err;
    char *enc_buf;

    enc_buf = encode? native_to_utf8 (buf) : xstrdup (buf);
    err = gpgme_data_new_from_mem (in, enc_buf, strlen (enc_buf), 1);
    free_if_alloc (enc_buf);
    return err;
}


/* Map gpgme data object to a string. */
void
map_gpgme_data (gpgme_data_t out, char **r_msg)
{
    size_t len = 0;
    char *p;

    p = gpgme_data_release_and_get_mem (out, &len);
    free_if_alloc (*r_msg);
    *r_msg = xcalloc (1, len+1);
    memcpy (*r_msg, p, len);
    gpgme_free (p);
}


/* Try to extract the needed key information and retrieve
   the keys if possible. */
static gpgme_error_t
get_keys (plugin_ctx_t ctx, recip_list_t *r_list, gpgme_key_t **r_keys)
{
    gpgme_key_t *keys;
    recip_list_t addrs = NULL, n;
    int rcount = 0, nkeys = 0;
    int i;

    if (ctx->to && strlen (ctx->to) >= 3)
        rcount += parse_recipients (ctx, &addrs, ctx->to);
    if (ctx->cc && strlen (ctx->cc) >= 3)
        rcount += parse_recipients (ctx, &addrs, ctx->cc);
    if (ctx->bcc && strlen (ctx->bcc) >= 3)
        rcount += parse_recipients (ctx, &addrs, ctx->bcc);

    nkeys = get_keys_from_addresses (addrs);
    /* at least some keys were not found, so we offer to select them. */
    if (nkeys != rcount) {
        ctx->rset = addrs;
        rcount = DialogBoxParam (mod_hinst_dll, (LPCTSTR)IDD_ENCRYPT, 
                                 ctx->main_wnd, encrypt_dlg_proc, (LPARAM)ctx);
        if (rcount == 0)
            return gpg_error (GPG_ERR_NO_PUBKEY);
        nkeys += rcount;
    }

    keys = xcalloc (nkeys+1, sizeof *keys);
    for (n = addrs, i=0; n; n = n->next) {
        if (n->key != NULL)
            keys[i++] = n->key;
    }
    *r_list = addrs;
    *r_keys = keys;
    return 0;
}


/* Encrypt the given message @r_msg with the recipients from the
   To, Cc, Bcc fields. In case that a recipient was not found
   use the recipient dialog so the user can select the missing keys. */
static gpgme_error_t
encrypt_msg (plugin_ctx_t ctx, char **r_msg)
{
    gpgme_error_t err;
    gpgme_key_t *keys = NULL;
    gpgme_ctx_t gctx = NULL;
    gpgme_data_t in = NULL, out = NULL;
    recip_list_t list = NULL;
    char *msg = *r_msg;

    assert (ctx);

    err = get_keys (ctx, &list, &keys);
    if (err)
        return err;

    err = gpgme_new (&gctx);
    if (!err)
        err = create_in_data (&in, msg, ctx->use_utf8);
    if (!err)
        err = gpgme_data_new (&out);
    if (!err) {
        gpgme_set_armor (gctx, 1);
        gpgme_set_textmode (gctx, 1);
        err = gpgme_op_encrypt (gctx, keys, 
                                GPGME_ENCRYPT_ALWAYS_TRUST, in, out);
    }

    gpgme_release (gctx);
    gpgme_data_release (in);
    release_recipient (list);
    free_if_alloc (keys);

    if (err)
        gpgme_data_release (out);
    else
        map_gpgme_data (out, r_msg);
    return err;
}


/* Sign the message given in @r_msg with the GPG default key. */
static gpgme_error_t
sign_msg (plugin_ctx_t ctx, char **r_msg)
{
    gpgme_error_t err;
    gpgme_ctx_t gctx;
    gpgme_data_t in, out;
    pass_cb_t cb_val;
    int cancel;

    cb_val = new_pass_cb (ctx->main_wnd);

    err = gpgme_new (&gctx);
    if (!err)
        err = gpgme_data_new_from_mem (&in, *r_msg, strlen (*r_msg), 1);
    if (!err)
        err = gpgme_data_new (&out);
    if (!err) {
        gpgme_set_passphrase_cb (gctx, passphrase_cb, cb_val);
        err = gpgme_op_sign (gctx, in, out, GPGME_SIG_MODE_CLEAR);
    }

    cancel = pass_cb_cancelled (cb_val);

    gpgme_release (gctx);
    gpgme_data_release (in);
    free_pass_cb (cb_val);

    if (err || cancel)
        gpgme_data_release (out);
    else
        map_gpgme_data (out, r_msg);

    return cancel? 0 : err;
}


/* Sign and encrypt the message @r_msg. */
static gpgme_error_t
sign_encrypt_msg (plugin_ctx_t ctx, char **r_msg)
{
    gpgme_ctx_t gctx;
    gpgme_data_t in, out;
    gpgme_error_t err;    
    gpgme_key_t *keys;
    pass_cb_t cb_val;
    recip_list_t list = NULL;
    int cancel;

    err = get_keys (ctx, &list, &keys);
    if (err)
        return err;

    cb_val = new_pass_cb (ctx->main_wnd);

    err = gpgme_new (&gctx);
    if (!err)
        err = create_in_data (&in, *r_msg, ctx->use_utf8);
    if (!err)
        err = gpgme_data_new (&out);
    if (!err) {
        gpgme_set_armor (gctx, 1);
        gpgme_set_textmode (gctx, 1);
        gpgme_set_passphrase_cb (gctx, passphrase_cb, cb_val);
        err = gpgme_op_encrypt_sign (gctx, keys, GPGME_ENCRYPT_ALWAYS_TRUST, 
                                     in, out);
    }

    cancel = pass_cb_cancelled (cb_val);

    gpgme_release (gctx);
    gpgme_data_release (in);
    release_recipient (list);
    free_if_alloc (keys);
    free_pass_cb (cb_val);

    if (err || cancel)
        gpgme_data_release (out);
    else
        map_gpgme_data (out, r_msg);
    return cancel? 0 : err;
}


static gpgme_error_t
verify_msg (plugin_ctx_t ctx, char **r_msg)
{   
    gpgme_error_t err;
    gpgme_ctx_t gctx;
    gpgme_data_t out = NULL;
    gpgme_data_t sig = NULL;
    gpgme_verify_result_t res;
    
    err = gpgme_new (&gctx);
    if (!err)
        err = gpgme_data_new_from_mem (&sig, *r_msg, strlen (*r_msg), 1);
    if (!err)
        err = gpgme_data_new (&out);
    if (!err)
        err = gpgme_op_verify (gctx, sig, NULL, out);
    if (!err) {
        res = gpgme_op_verify_result (gctx);
        if (res && res->signatures)
            DialogBoxParam (mod_hinst_dll, (LPCTSTR)IDD_VERIFY, ctx->main_wnd,
                            verify_dlg_proc, (LPARAM)res->signatures);
    }

    gpgme_release (gctx);
    gpgme_data_release (sig);
    
    if (!err)
        map_gpgme_data (out, r_msg);
    else
        gpgme_data_release (out);
    return err;
}


/* Detailed error message when the decryption failed. */
static void
store_decrypt_info (char *buf, size_t buflen,
                    gpgme_decrypt_result_t res)
{
    gpgme_key_t key = NULL;
    gpgme_ctx_t ctx;
    int algo;
    
    if (!res->recipients)
        return;

    if (!gpgme_new (&ctx)) {
        gpgme_get_key (ctx, res->recipients->keyid, &key, 0);
        gpgme_release (ctx);
    }

    algo = res->recipients->pubkey_algo;
    if (!key)
        _snprintf (buf, buflen, _("encrypted with %s key, ID %s\n"
                                "decryption failed: secret key not available"),
                                algo == 1? "RSA" : algo==16? "ELG": "???", 
                                res->recipients->keyid+8);
    else {
        char *uid = utf8_to_native (key->uids->uid);
        _snprintf (buf, buflen, _("encrypted with %d-bit %s key, ID %s\n"
                                "\t\"%s\"\n"
                                "decryption failed: secret key not available"),
                                key->subkeys->length, 
                                algo == 1? "RSA" : algo==16? "ELG": "???",
                                key->subkeys->keyid+8, uid);
        free_if_alloc (uid);
    }
    if (key)
        gpgme_key_release (key);
}


/* Decrypt the message given in @r_msg.
   The old message will be freed and replaced with the plaintext. */
gpgme_error_t
oe_decrypt_msg (HWND main_wnd, char **r_msg)
{
    gpgme_ctx_t gctx = NULL;
    gpgme_data_t in = NULL, out = NULL;
    gpgme_error_t err;
    pass_cb_t cb_val;
    int cancel;
    char *msg = *r_msg;

    cb_val = new_pass_cb (main_wnd);
    err = gpgme_new (&gctx);
    if (!err)
        err = gpgme_data_new_from_mem (&in, msg, strlen (msg), 1);
    if (!err)
        err = gpgme_data_new (&out);
    if (!err) {
        gpgme_set_passphrase_cb (gctx, passphrase_cb, cb_val);
        err = gpgme_op_decrypt (gctx, in, out);
    }

    cancel = pass_cb_cancelled (cb_val);        

    gpgme_release (gctx);
    gpgme_data_release (in);
    free_pass_cb (cb_val);
    
    if (err || cancel)
        gpgme_data_release (out);
    else
        map_gpgme_data (out, r_msg);

    return cancel? 0 : err;
}


/* Decrypt the message @r_msg. If the type @type is actually a signature,
   the verify function is called instead of decryption. */
static gpgme_error_t
decrypt_msg (plugin_ctx_t ctx, char **r_msg, int type, int *r_cancel)
{
    gpgme_ctx_t gctx = NULL;
    gpgme_data_t in = NULL, out = NULL;
    gpgme_error_t err;
    gpgme_verify_result_t res;
    pass_cb_t cb_val;
    char *msg = *r_msg;

    if ((type & PGP_SIG) || (type & PGP_CLEARSIG))
        return verify_msg (ctx, r_msg);

    cb_val = new_pass_cb (ctx->main_wnd);

    err = gpgme_new (&gctx);
    if (!err)
        err = gpgme_data_new_from_mem (&in, msg, strlen (msg), 1);
    if (!err)
        err = gpgme_data_new (&out);
    if (!err) {
        gpgme_set_passphrase_cb (gctx, passphrase_cb, cb_val);
        err = gpgme_op_decrypt_verify (gctx, in, out);
        res = gpgme_op_verify_result (gctx);
        if (res && res->signatures)
            DialogBoxParam (mod_hinst_dll, (LPCTSTR)IDD_VERIFY, ctx->main_wnd,
                            verify_dlg_proc, (LPARAM)res->signatures);
    }
    *r_cancel = pass_cb_cancelled (cb_val);

    if (!*r_cancel && err) {
        gpgme_decrypt_result_t r = gpgme_op_decrypt_result (gctx);
        store_decrypt_info (ctx->errbuf, sizeof (ctx->errbuf)-1, r);
    }

    gpgme_release (gctx);
    gpgme_data_release (in);
    free_pass_cb (cb_val);
    
    if (err || *r_cancel)
        gpgme_data_release (out);
    else
        map_gpgme_data (out, r_msg);

    return *r_cancel? 0 : err;
}


/* Return what kind of OpenPGP message @msg is. */
static int
parse_pgp_id (const char *msg)
{
    int id = 0;

    if (strstr (msg, "BEGIN PGP MESSAGE"))
        id |= PGP_MESSAGE;
    if (strstr (msg, "BEGIN PGP PUBLIC KEY") ||
        strstr (msg, "BEGIN PGP SECRET KEY") ||
        strstr (msg, "BEGIN PGP PRIVATE KEY"))
        id |= PGP_KEY;
    if (strstr (msg, "BEGIN PGP SIGNED MESSAGE"))
        id |= PGP_CLEARSIG;
    return id;
}


static int
winpt_key_import (void)
{
    HWND winpt;

    winpt = FindWindow ("WinPT", "WinPT");
    if (winpt != NULL) {
        PostMessage (winpt, WM_COMMAND, 40014, 0);
        return 0;
    }
    return -1;
}


/* Try to decrypt a PGP/MIME message. */
static gpgme_error_t
oe_handle_pgp_mime_mail (plugin_ctx_t ctx)
{
    SetEvent (plugin_active);

    /* Select attachment number 0. */
    AttachThreadInput (GetCurrentThreadId (),
                       GetWindowThreadProcessId (ctx->main_wnd, NULL),
                       TRUE);

    SetFocus (ctx->addr_wnd);
    SetFocus (ctx->attach);
    ListView_SetItemState (ctx->attach, 0, LVIS_SELECTED|LVIS_FOCUSED, 
                           LVIS_FOCUSED|LVIS_SELECTED);

    AttachThreadInput (GetCurrentThreadId (),
                       GetWindowThreadProcessId (ctx->main_wnd, NULL),
                       FALSE);
    
    SendMessage (ctx->addr_wnd, WM_COMMAND, ID_OE_SAVE_ATT, 0);

    ResetEvent (plugin_active);

    return 0;
}


/* This function can be use for all kind of OE messages.
   It automatically choose the right procedure to handle the data. */
gpgme_error_t
oe_handle_mail (plugin_ctx_t ctx)
{
    gpgme_error_t rc = 0;
    char *msg;
    int msg_type = 0;
    int cancel;

    assert (ctx);

    msg = window_get_message (ctx->main_wnd);
#if 0
    if ((!msg || strlen (msg)) < 2 && 
        ctx->attach && ListView_GetItemCount (ctx->attach) == 2) {
        free_if_alloc (msg);
        return oe_handle_pgp_mime_mail (ctx);
    }
#endif
    if (!msg || strlen (msg) == 2) {
        free_if_alloc (msg);
        return 0;
    }

    if (strstr (msg, "-----BEGIN PGP") &&
        strstr (msg, "-----END PGP"))
        msg_type = parse_pgp_id (msg);

    if (msg_type & PGP_KEY) {
        if (winpt_key_import ())
            MessageBox (ctx->main_wnd,
                    _("This mail contains one or more public or secret keys.\n\n"
                      "Please save the mail text in a file to use WinPT to import them."),
                      _("GPG Plug-in Info"), MB_ICONINFORMATION|MB_OK);
    }
    else if (msg_type) {
        rc = decrypt_msg (ctx, &msg, msg_type, &cancel);
        SendMessage (ctx->msg_wnd, WM_CLEAR, 0, 0);
        SendMessage (ctx->msg_wnd, WM_UNDO, 0, 0);
        if (!cancel && !rc && (msg_type & PGP_MESSAGE) 
            && msg && strlen (msg) > 0) {
            struct viewer_ctx_s viewer;
            viewer.msg = msg;
            viewer.main_wnd = ctx->main_wnd;
            DialogBoxParam (mod_hinst_dll, (LPCTSTR)IDD_VIEWER, ctx->main_wnd,
                            viewer_dlg_proc, (LPARAM)&viewer);
        }
    }
    else if (ctx->sign || ctx->encrypt) {
        if (!ctx->to && !ctx->cc && !ctx->bcc) {
            free_if_alloc (msg);
            return gpg_error (GPG_ERR_NO_DATA);
        }
        if (ctx->sign && ctx->encrypt)
            rc = sign_encrypt_msg (ctx, &msg);
        else if (ctx->sign)
            rc = sign_msg (ctx, &msg);
        else if (ctx->encrypt)
            rc = encrypt_msg (ctx, &msg);
        window_set_message (ctx->main_wnd, msg);
    }

    free_if_alloc (msg);
    return rc;
}
1	twoaday	1	/* OECrypto.c - OE crypto functions
2			* Copyright (C) 2001, 2002, 2003, 2006 Timo Schulz
3			*
4			* This file is part of GPGOE.
5			*
6			* GPGOE is free software; you can redistribute it and/or modify
7			* it under the terms of the GNU Lesser General Public License as published by
8			* the Free Software Foundation; either version 2.1 of the License, or
9			* (at your option) any later version.
10			*
11			* GPGOE is distributed in the hope that it will be useful,
12			* but WITHOUT ANY WARRANTY; without even the implied warranty of
13			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14			* GNU General Public License for more details.
15			*
16			* You should have received a copy of the GNU Lesser General Public License
17			* along with GPGOE; if not, write to the Free Software Foundation,
18			* Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
19			*/
20
21			#ifdef HAVE_CONFIG_H
22			#include <config.h>
23			#endif
24			#include <windows.h>
25			#include <assert.h>
26	twoaday	12	#include <commctrl.h>
27
28	twoaday	1	#include "resource.h"
29			#include "gpgme.h"
30			#include "GPGOE.h"
31
32
33			/* Valid OpenPGP message types. */
34			enum {
35	twoaday	12	PGP_MESSAGE = 1,
36			PGP_CLEARSIG = 2,
37			PGP_SIG = 4,
38			PGP_KEY = 8,
39	twoaday	1	};
40
41
42	twoaday	10	/* Move the keyboard focus to the message window
43			to copy the text to the clipboard. */
44	twoaday	1	static void
45			set_focus (HWND main)
46			{
47			HWND doc, mime, msg;
48
49			doc = FindWindowEx (main, NULL, "ME_DocHost", NULL );
50			mime = FindWindowEx (doc, NULL, "##MimeEdit_Server", NULL);
51			msg = FindWindowEx (mime, NULL, "Internet Explorer_Server", NULL);
52
53			AttachThreadInput (GetCurrentThreadId (),
54			GetWindowThreadProcessId (main, NULL),
55			TRUE);
56
57			SetFocus (doc);
58			SetFocus (mime);
59			SetFocus (msg);
60
61			AttachThreadInput (GetCurrentThreadId (),
62			GetWindowThreadProcessId (main, NULL),
63			FALSE);
64			}
65
66
67			/* Copy the message to the clipboard and then return the clipboard
68			data (which is the message). */
69			static char*
70			window_get_message (HWND main_hwnd)
71			{
72			set_focus (main_hwnd);
73			SetForegroundWindow (main_hwnd);
74	twoaday	12	SendMessage (main_hwnd, WM_COMMAND, MAKEWPARAM (ID_OE_SELECTALL, 0), 0);
75			SendMessage (main_hwnd, WM_COMMAND, MAKEWPARAM (ID_OE_COPY, 0), 0);
76	twoaday	1
77	twoaday	10	/* even so SendMessage() should wait, we wait for safety reasons. */
78	twoaday	1	Sleep (200);
79	twoaday	10	return get_clip_text (NULL);
80	twoaday	1	}
81
82
83			/* Paste the message given in @msg into the window @main_hwnd.
84			To make sure all existing text is overwritten, "select all"
85			is send to the window first. */
86			static void
87			window_set_message (HWND main_hwnd, const char *msg)
88			{
89			set_clip_text (NULL, msg, strlen (msg));
90			set_focus (main_hwnd);
91			SetForegroundWindow (main_hwnd);
92	twoaday	12	SendMessage (main_hwnd, WM_COMMAND, MAKEWPARAM (ID_OE_SELECTALL, 0), 0);
93			SendMessage (main_hwnd, WM_COMMAND, MAKEWPARAM (ID_OE_PASTE, 0), 0);
94	twoaday	1	}
95
96
97			/* Try to find the given recipient by key @key and
98			return it (NULL in case of error). */
99			static recip_list_t
100			find_recipient (recip_list_t rset, gpgme_key_t key)
101			{
102			recip_list_t n;
103			gpgme_user_id_t u;
104
105			for (n = rset; n; n = n->next) {
106			for (u = key->uids; u; u = u->next) {
107			if (u->email && strstr (u->email, n->addr))
108			return n;
109			}
110			}
111			return NULL;
112			}
113
114
115			/* Add recipient with address @addr and key @key to @rset. */
116			void
117			add_recipient (recip_list_t rset, const char addr, gpgme_key_t key)
118			{
119			recip_list_t r, n;
120
121			r = xcalloc (1, sizeof *r);
122			r->addr = xstrdup (addr);
123			r->key = key;
124			if (!*rset)
125			*rset = r;
126			else {
127			for (n=*rset; n->next; n=n->next)
128			;
129			n->next = r;
130			}
131			}
132
133
134			/* Release recipient list @rset. */
135			static void
136			release_recipient (recip_list_t rset)
137			{
138			recip_list_t n;
139
140			while (rset != NULL) {
141			n = rset->next;
142			if (rset->key)
143			gpgme_key_release (rset->key);
144			free_if_alloc (rset->addr);
145			free_if_alloc (rset);
146			rset = n;
147			}
148			}
149
150
151			/* This functions converts the OE recipient fields to GPG compatible fields.
152			Currently the function support the following 'From' styles:
153			John Hacker <[email protected]>; [email protected]
154			or Foo Bar <[email protected]>, [email protected].
155			only the part between '<' '>' are added.
156			*/
157			static int
158			parse_recipients (plugin_ctx_t ctx, recip_list_t rset, char recpt)
159			{
160			char token, p;
161			int count = 0;
162			char p1, p2;
163			int n1, n2;
164
165			assert (recpt && rset);
166
167			token = strtok (recpt, ",;");
168			while (token != NULL ) {
169			if ((p1=strchr (token, '<')) && (p2=strchr (token, '>'))
170			&& strchr (token, '@')) {
171			n1 = p1 - token + 1 ;
172			n2 = p2 - token + 1;
173
174			p = xcalloc (1, strlen (token) + 1);
175			memcpy (p, token+n1, n2-n1-1);
176			add_recipient (rset, p, NULL);
177			count++;
178			free_if_alloc (p);
179			}
180			else if (strchr (token, '@') && !strchr (token, ' ')) {
181			p = xcalloc (1, strlen (token) + 1);
182			memcpy (p, token, strlen (token));
183			add_recipient (rset, p, NULL);
184			count++;
185			free_if_alloc (p);
186			}
187			token = strtok (NULL, ",;");
188			}
189			return count;
190			}
191
192
193	twoaday	10	/* Fill in the key part of the recipient list @addrs if possible. */
194	twoaday	1	static int
195			get_keys_from_addresses (recip_list_t addrs)
196			{
197			gpgme_ctx_t ctx;
198			gpgme_error_t err;
199			gpgme_key_t pk;
200			recip_list_t n, fnd;
201			char *p;
202			int nkeys=0;
203			DWORD len=0;
204
205			for (n = addrs; n; n = n->next)
206			len += strlen (n->addr) + 3;
207			p = xcalloc (1, len + 1);
208			for (n = addrs; n; n = n->next) {
209			strcat (p, n->addr);
210			strcat (p, " ");
211			}
212
213			err = gpgme_new (&ctx);
214			if (!err)
215			err = gpgme_op_keylist_start (ctx, p, 0);
216			while (!err) {
217			err = gpgme_op_keylist_next (ctx, &pk);
218			if (err)
219			break;
220	twoaday	10	/* do not add invalid keys. */
221	twoaday	1	if (pk->disabled \|\| pk->expired \|\| pk->revoked)
222			continue;
223			fnd = find_recipient (addrs, pk);
224			if (fnd != NULL && pk->can_encrypt) {
225			fnd->key = pk;
226			nkeys++;
227			}
228			}
229
230			gpgme_release (ctx);
231			free_if_alloc (p);
232			return nkeys;
233			}
234
235
236	twoaday	12	/* Create gpgme input data object. If @encode is 1, use UTF8 conversion. */
237			gpgme_error_t
238			create_in_data (gpgme_data_t in, const char buf, int encode)
239			{
240			gpgme_error_t err;
241			char *enc_buf;
242
243			enc_buf = encode? native_to_utf8 (buf) : xstrdup (buf);
244			err = gpgme_data_new_from_mem (in, enc_buf, strlen (enc_buf), 1);
245	twoaday	16	free_if_alloc (enc_buf);
246	twoaday	12	return err;
247			}
248
249
250	twoaday	1	/* Map gpgme data object to a string. */
251			void
252			map_gpgme_data (gpgme_data_t out, char **r_msg)
253			{
254			size_t len = 0;
255			char *p;
256
257			p = gpgme_data_release_and_get_mem (out, &len);
258			free_if_alloc (*r_msg);
259			*r_msg = xcalloc (1, len+1);
260			memcpy (*r_msg, p, len);
261			gpgme_free (p);
262			}
263
264
265			/* Try to extract the needed key information and retrieve
266			the keys if possible. */
267			static gpgme_error_t
268	twoaday	16	get_keys (plugin_ctx_t ctx, recip_list_t r_list, gpgme_key_t *r_keys)
269	twoaday	1	{
270			gpgme_key_t *keys;
271			recip_list_t addrs = NULL, n;
272			int rcount = 0, nkeys = 0;
273			int i;
274
275			if (ctx->to && strlen (ctx->to) >= 3)
276			rcount += parse_recipients (ctx, &addrs, ctx->to);
277			if (ctx->cc && strlen (ctx->cc) >= 3)
278			rcount += parse_recipients (ctx, &addrs, ctx->cc);
279			if (ctx->bcc && strlen (ctx->bcc) >= 3)
280			rcount += parse_recipients (ctx, &addrs, ctx->bcc);
281
282			nkeys = get_keys_from_addresses (addrs);
283	twoaday	10	/* at least some keys were not found, so we offer to select them. */
284	twoaday	1	if (nkeys != rcount) {
285			ctx->rset = addrs;
286			rcount = DialogBoxParam (mod_hinst_dll, (LPCTSTR)IDD_ENCRYPT,
287			ctx->main_wnd, encrypt_dlg_proc, (LPARAM)ctx);
288			if (rcount == 0)
289			return gpg_error (GPG_ERR_NO_PUBKEY);
290			nkeys += rcount;
291			}
292
293			keys = xcalloc (nkeys+1, sizeof *keys);
294			for (n = addrs, i=0; n; n = n->next) {
295			if (n->key != NULL)
296			keys[i++] = n->key;
297			}
298			*r_list = addrs;
299			*r_keys = keys;
300			return 0;
301			}
302
303
304	twoaday	10	/* Encrypt the given message @r_msg with the recipients from the
305			To, Cc, Bcc fields. In case that a recipient was not found
306			use the recipient dialog so the user can select the missing keys. */
307	twoaday	1	static gpgme_error_t
308			encrypt_msg (plugin_ctx_t ctx, char **r_msg)
309			{
310			gpgme_error_t err;
311			gpgme_key_t *keys = NULL;
312			gpgme_ctx_t gctx = NULL;
313			gpgme_data_t in = NULL, out = NULL;
314			recip_list_t list = NULL;
315			char msg = r_msg;
316
317			assert (ctx);
318
319	twoaday	16	err = get_keys (ctx, &list, &keys);
320	twoaday	10	if (err)
321			return err;
322	twoaday	1
323			err = gpgme_new (&gctx);
324			if (!err)
325	twoaday	12	err = create_in_data (&in, msg, ctx->use_utf8);
326	twoaday	1	if (!err)
327			err = gpgme_data_new (&out);
328			if (!err) {
329			gpgme_set_armor (gctx, 1);
330	twoaday	6	gpgme_set_textmode (gctx, 1);
331	twoaday	10	err = gpgme_op_encrypt (gctx, keys,
332			GPGME_ENCRYPT_ALWAYS_TRUST, in, out);
333	twoaday	1	}
334
335			gpgme_release (gctx);
336			gpgme_data_release (in);
337			release_recipient (list);
338	twoaday	16	free_if_alloc (keys);
339	twoaday	1
340	twoaday	10	if (err)
341	twoaday	1	gpgme_data_release (out);
342	twoaday	10	else
343			map_gpgme_data (out, r_msg);
344			return err;
345	twoaday	1	}
346
347
348	twoaday	10	/* Sign the message given in @r_msg with the GPG default key. */
349	twoaday	1	static gpgme_error_t
350			sign_msg (plugin_ctx_t ctx, char **r_msg)
351			{
352			gpgme_error_t err;
353			gpgme_ctx_t gctx;
354			gpgme_data_t in, out;
355			pass_cb_t cb_val;
356	twoaday	18	int cancel;
357	twoaday	1
358			cb_val = new_pass_cb (ctx->main_wnd);
359
360			err = gpgme_new (&gctx);
361			if (!err)
362			err = gpgme_data_new_from_mem (&in, r_msg, strlen (r_msg), 1);
363			if (!err)
364			err = gpgme_data_new (&out);
365			if (!err) {
366			gpgme_set_passphrase_cb (gctx, passphrase_cb, cb_val);
367			err = gpgme_op_sign (gctx, in, out, GPGME_SIG_MODE_CLEAR);
368			}
369
370	twoaday	18	cancel = pass_cb_cancelled (cb_val);
371
372	twoaday	1	gpgme_release (gctx);
373			gpgme_data_release (in);
374			free_pass_cb (cb_val);
375
376	twoaday	18	if (err \|\| cancel)
377	twoaday	1	gpgme_data_release (out);
378	twoaday	10	else
379			map_gpgme_data (out, r_msg);
380	twoaday	1
381	twoaday	18	return cancel? 0 : err;
382	twoaday	1	}
383
384
385	twoaday	10	/* Sign and encrypt the message @r_msg. */
386	twoaday	1	static gpgme_error_t
387			sign_encrypt_msg (plugin_ctx_t ctx, char **r_msg)
388			{
389			gpgme_ctx_t gctx;
390			gpgme_data_t in, out;
391			gpgme_error_t err;
392			gpgme_key_t *keys;
393			pass_cb_t cb_val;
394			recip_list_t list = NULL;
395	twoaday	18	int cancel;
396	twoaday	1
397	twoaday	16	err = get_keys (ctx, &list, &keys);
398			if (err)
399			return err;
400	twoaday	1
401			cb_val = new_pass_cb (ctx->main_wnd);
402
403			err = gpgme_new (&gctx);
404			if (!err)
405	twoaday	12	err = create_in_data (&in, *r_msg, ctx->use_utf8);
406	twoaday	1	if (!err)
407			err = gpgme_data_new (&out);
408			if (!err) {
409			gpgme_set_armor (gctx, 1);
410	twoaday	6	gpgme_set_textmode (gctx, 1);
411	twoaday	1	gpgme_set_passphrase_cb (gctx, passphrase_cb, cb_val);
412			err = gpgme_op_encrypt_sign (gctx, keys, GPGME_ENCRYPT_ALWAYS_TRUST,
413			in, out);
414			}
415
416	twoaday	18	cancel = pass_cb_cancelled (cb_val);
417
418	twoaday	1	gpgme_release (gctx);
419			gpgme_data_release (in);
420			release_recipient (list);
421	twoaday	16	free_if_alloc (keys);
422	twoaday	1	free_pass_cb (cb_val);
423
424	twoaday	18	if (err \|\| cancel)
425	twoaday	1	gpgme_data_release (out);
426	twoaday	10	else
427			map_gpgme_data (out, r_msg);
428	twoaday	18	return cancel? 0 : err;
429	twoaday	1	}
430
431
432			static gpgme_error_t
433			verify_msg (plugin_ctx_t ctx, char **r_msg)
434			{
435			gpgme_error_t err;
436			gpgme_ctx_t gctx;
437			gpgme_data_t out = NULL;
438			gpgme_data_t sig = NULL;
439			gpgme_verify_result_t res;
440
441			err = gpgme_new (&gctx);
442			if (!err)
443			err = gpgme_data_new_from_mem (&sig, r_msg, strlen (r_msg), 1);
444			if (!err)
445			err = gpgme_data_new (&out);
446			if (!err)
447			err = gpgme_op_verify (gctx, sig, NULL, out);
448			if (!err) {
449			res = gpgme_op_verify_result (gctx);
450			if (res && res->signatures)
451			DialogBoxParam (mod_hinst_dll, (LPCTSTR)IDD_VERIFY, ctx->main_wnd,
452			verify_dlg_proc, (LPARAM)res->signatures);
453			}
454
455			gpgme_release (gctx);
456			gpgme_data_release (sig);
457	twoaday	10
458			if (!err)
459			map_gpgme_data (out, r_msg);
460			else
461			gpgme_data_release (out);
462	twoaday	1	return err;
463			}
464
465
466			/* Detailed error message when the decryption failed. */
467			static void
468			store_decrypt_info (char *buf, size_t buflen,
469			gpgme_decrypt_result_t res)
470			{
471			gpgme_key_t key = NULL;
472			gpgme_ctx_t ctx;
473			int algo;
474
475			if (!res->recipients)
476			return;
477
478			if (!gpgme_new (&ctx)) {
479			gpgme_get_key (ctx, res->recipients->keyid, &key, 0);
480			gpgme_release (ctx);
481			}
482
483			algo = res->recipients->pubkey_algo;
484			if (!key)
485			_snprintf (buf, buflen, _("encrypted with %s key, ID %s\n"
486	twoaday	12	"decryption failed: secret key not available"),
487	twoaday	1	algo == 1? "RSA" : algo==16? "ELG": "???",
488			res->recipients->keyid+8);
489			else {
490			char *uid = utf8_to_native (key->uids->uid);
491			_snprintf (buf, buflen, _("encrypted with %d-bit %s key, ID %s\n"
492			"\t\"%s\"\n"
493	twoaday	12	"decryption failed: secret key not available"),
494	twoaday	1	key->subkeys->length,
495			algo == 1? "RSA" : algo==16? "ELG": "???",
496			key->subkeys->keyid+8, uid);
497			free_if_alloc (uid);
498			}
499			if (key)
500			gpgme_key_release (key);
501			}
502
503
504	twoaday	16	/* Decrypt the message given in @r_msg.
505			The old message will be freed and replaced with the plaintext. */
506			gpgme_error_t
507			oe_decrypt_msg (HWND main_wnd, char **r_msg)
508			{
509			gpgme_ctx_t gctx = NULL;
510			gpgme_data_t in = NULL, out = NULL;
511			gpgme_error_t err;
512			pass_cb_t cb_val;
513	twoaday	18	int cancel;
514	twoaday	16	char msg = r_msg;
515
516			cb_val = new_pass_cb (main_wnd);
517			err = gpgme_new (&gctx);
518			if (!err)
519			err = gpgme_data_new_from_mem (&in, msg, strlen (msg), 1);
520			if (!err)
521			err = gpgme_data_new (&out);
522			if (!err) {
523			gpgme_set_passphrase_cb (gctx, passphrase_cb, cb_val);
524			err = gpgme_op_decrypt (gctx, in, out);
525			}
526
527	twoaday	18	cancel = pass_cb_cancelled (cb_val);
528
529	twoaday	16	gpgme_release (gctx);
530			gpgme_data_release (in);
531			free_pass_cb (cb_val);
532
533	twoaday	18	if (err \|\| cancel)
534	twoaday	16	gpgme_data_release (out);
535			else
536			map_gpgme_data (out, r_msg);
537
538	twoaday	18	return cancel? 0 : err;
539	twoaday	16	}
540
541
542	twoaday	10	/* Decrypt the message @r_msg. If the type @type is actually a signature,
543			the verify function is called instead of decryption. */
544	twoaday	1	static gpgme_error_t
545	twoaday	18	decrypt_msg (plugin_ctx_t ctx, char *r_msg, int type, int r_cancel)
546	twoaday	1	{
547			gpgme_ctx_t gctx = NULL;
548			gpgme_data_t in = NULL, out = NULL;
549			gpgme_error_t err;
550			gpgme_verify_result_t res;
551			pass_cb_t cb_val;
552			char msg = r_msg;
553
554			if ((type & PGP_SIG) \|\| (type & PGP_CLEARSIG))
555			return verify_msg (ctx, r_msg);
556
557			cb_val = new_pass_cb (ctx->main_wnd);
558
559			err = gpgme_new (&gctx);
560			if (!err)
561			err = gpgme_data_new_from_mem (&in, msg, strlen (msg), 1);
562			if (!err)
563			err = gpgme_data_new (&out);
564			if (!err) {
565			gpgme_set_passphrase_cb (gctx, passphrase_cb, cb_val);
566			err = gpgme_op_decrypt_verify (gctx, in, out);
567			res = gpgme_op_verify_result (gctx);
568			if (res && res->signatures)
569			DialogBoxParam (mod_hinst_dll, (LPCTSTR)IDD_VERIFY, ctx->main_wnd,
570			verify_dlg_proc, (LPARAM)res->signatures);
571			}
572	twoaday	18	*r_cancel = pass_cb_cancelled (cb_val);
573
574			if (!*r_cancel && err) {
575	twoaday	1	gpgme_decrypt_result_t r = gpgme_op_decrypt_result (gctx);
576			store_decrypt_info (ctx->errbuf, sizeof (ctx->errbuf)-1, r);
577			}
578
579			gpgme_release (gctx);
580			gpgme_data_release (in);
581			free_pass_cb (cb_val);
582
583	twoaday	18	if (err \|\| *r_cancel)
584	twoaday	1	gpgme_data_release (out);
585	twoaday	10	else
586			map_gpgme_data (out, r_msg);
587	twoaday	1
588	twoaday	18	return *r_cancel? 0 : err;
589	twoaday	1	}
590
591
592			/* Return what kind of OpenPGP message @msg is. */
593			static int
594			parse_pgp_id (const char *msg)
595			{
596			int id = 0;
597
598			if (strstr (msg, "BEGIN PGP MESSAGE"))
599			id \|= PGP_MESSAGE;
600			if (strstr (msg, "BEGIN PGP PUBLIC KEY") \|\|
601			strstr (msg, "BEGIN PGP SECRET KEY") \|\|
602			strstr (msg, "BEGIN PGP PRIVATE KEY"))
603			id \|= PGP_KEY;
604			if (strstr (msg, "BEGIN PGP SIGNED MESSAGE"))
605			id \|= PGP_CLEARSIG;
606			return id;
607			}
608
609
610	twoaday	12	static int
611			winpt_key_import (void)
612			{
613			HWND winpt;
614
615			winpt = FindWindow ("WinPT", "WinPT");
616			if (winpt != NULL) {
617			PostMessage (winpt, WM_COMMAND, 40014, 0);
618			return 0;
619			}
620			return -1;
621			}
622
623
624			/* Try to decrypt a PGP/MIME message. */
625			static gpgme_error_t
626			oe_handle_pgp_mime_mail (plugin_ctx_t ctx)
627			{
628			SetEvent (plugin_active);
629
630			/* Select attachment number 0. */
631			AttachThreadInput (GetCurrentThreadId (),
632			GetWindowThreadProcessId (ctx->main_wnd, NULL),
633			TRUE);
634
635			SetFocus (ctx->addr_wnd);
636			SetFocus (ctx->attach);
637			ListView_SetItemState (ctx->attach, 0, LVIS_SELECTED\|LVIS_FOCUSED,
638			LVIS_FOCUSED\|LVIS_SELECTED);
639
640			AttachThreadInput (GetCurrentThreadId (),
641			GetWindowThreadProcessId (ctx->main_wnd, NULL),
642			FALSE);
643
644			SendMessage (ctx->addr_wnd, WM_COMMAND, ID_OE_SAVE_ATT, 0);
645
646			ResetEvent (plugin_active);
647
648			return 0;
649			}
650
651
652	twoaday	1	/* This function can be use for all kind of OE messages.
653			It automatically choose the right procedure to handle the data. */
654			gpgme_error_t
655			oe_handle_mail (plugin_ctx_t ctx)
656			{
657	twoaday	3	gpgme_error_t rc = 0;
658	twoaday	10	char *msg;
659	twoaday	1	int msg_type = 0;
660	twoaday	18	int cancel;
661	twoaday	1
662			assert (ctx);
663	twoaday	11
664	twoaday	1	msg = window_get_message (ctx->main_wnd);
665	twoaday	12	#if 0
666			if ((!msg \|\| strlen (msg)) < 2 &&
667			ctx->attach && ListView_GetItemCount (ctx->attach) == 2) {
668			free_if_alloc (msg);
669			return oe_handle_pgp_mime_mail (ctx);
670			}
671			#endif
672	twoaday	1	if (!msg \|\| strlen (msg) == 2) {
673			free_if_alloc (msg);
674			return 0;
675			}
676
677			if (strstr (msg, "-----BEGIN PGP") &&
678			strstr (msg, "-----END PGP"))
679			msg_type = parse_pgp_id (msg);
680
681			if (msg_type & PGP_KEY) {
682	twoaday	12	if (winpt_key_import ())
683			MessageBox (ctx->main_wnd,
684	twoaday	1	_("This mail contains one or more public or secret keys.\n\n"
685			"Please save the mail text in a file to use WinPT to import them."),
686			_("GPG Plug-in Info"), MB_ICONINFORMATION\|MB_OK);
687			}
688			else if (msg_type) {
689	twoaday	18	rc = decrypt_msg (ctx, &msg, msg_type, &cancel);
690	twoaday	1	SendMessage (ctx->msg_wnd, WM_CLEAR, 0, 0);
691			SendMessage (ctx->msg_wnd, WM_UNDO, 0, 0);
692	twoaday	18	if (!cancel && !rc && (msg_type & PGP_MESSAGE)
693			&& msg && strlen (msg) > 0) {
694	twoaday	1	struct viewer_ctx_s viewer;
695			viewer.msg = msg;
696	twoaday	16	viewer.main_wnd = ctx->main_wnd;
697	twoaday	1	DialogBoxParam (mod_hinst_dll, (LPCTSTR)IDD_VIEWER, ctx->main_wnd,
698			viewer_dlg_proc, (LPARAM)&viewer);
699			}
700			}
701	twoaday	11	else if (ctx->sign \|\| ctx->encrypt) {
702	twoaday	1	if (!ctx->to && !ctx->cc && !ctx->bcc) {
703			free_if_alloc (msg);
704			return gpg_error (GPG_ERR_NO_DATA);
705			}
706			if (ctx->sign && ctx->encrypt)
707			rc = sign_encrypt_msg (ctx, &msg);
708			else if (ctx->sign)
709			rc = sign_msg (ctx, &msg);
710			else if (ctx->encrypt)
711			rc = encrypt_msg (ctx, &msg);
712			window_set_message (ctx->main_wnd, msg);
713			}
714
715			free_if_alloc (msg);
716			return rc;
717			}