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 (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, int *r_n)
{
    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;
    *r_n = nkeys;
    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;
    int nkeys=0;
    char *msg = *r_msg;

    assert (ctx);

    err = get_keys (ctx, &list, &keys, &nkeys);
    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 (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;

    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);
    }

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

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

    return 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 ec, nkeys = 0;

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

    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);
    }

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

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

    return 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;

    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);
        SendMessage (ctx->msg_wnd, WM_CLEAR, 0, 0);
        SendMessage (ctx->msg_wnd, WM_UNDO, 0, 0);
        if (!rc && (msg_type & PGP_MESSAGE) && msg && strlen (msg) > 0) {
            struct viewer_ctx_s viewer;
            viewer.msg = msg;
            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			free (enc_buf);
246			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			get_keys (plugin_ctx_t ctx, recip_list_t *r_list,
269			gpgme_key_t *r_keys, int r_n)
270			{
271			gpgme_key_t *keys;
272			recip_list_t addrs = NULL, n;
273			int rcount = 0, nkeys = 0;
274			int i;
275
276			if (ctx->to && strlen (ctx->to) >= 3)
277			rcount += parse_recipients (ctx, &addrs, ctx->to);
278			if (ctx->cc && strlen (ctx->cc) >= 3)
279			rcount += parse_recipients (ctx, &addrs, ctx->cc);
280			if (ctx->bcc && strlen (ctx->bcc) >= 3)
281			rcount += parse_recipients (ctx, &addrs, ctx->bcc);
282
283			nkeys = get_keys_from_addresses (addrs);
284	twoaday	10	/* at least some keys were not found, so we offer to select them. */
285	twoaday	1	if (nkeys != rcount) {
286			ctx->rset = addrs;
287			rcount = DialogBoxParam (mod_hinst_dll, (LPCTSTR)IDD_ENCRYPT,
288			ctx->main_wnd, encrypt_dlg_proc, (LPARAM)ctx);
289			if (rcount == 0)
290			return gpg_error (GPG_ERR_NO_PUBKEY);
291			nkeys += rcount;
292			}
293
294			keys = xcalloc (nkeys+1, sizeof *keys);
295			for (n = addrs, i=0; n; n = n->next) {
296			if (n->key != NULL)
297			keys[i++] = n->key;
298			}
299			*r_list = addrs;
300			*r_keys = keys;
301			*r_n = nkeys;
302			return 0;
303			}
304
305
306	twoaday	10	/* Encrypt the given message @r_msg with the recipients from the
307			To, Cc, Bcc fields. In case that a recipient was not found
308			use the recipient dialog so the user can select the missing keys. */
309	twoaday	1	static gpgme_error_t
310			encrypt_msg (plugin_ctx_t ctx, char **r_msg)
311			{
312			gpgme_error_t err;
313			gpgme_key_t *keys = NULL;
314			gpgme_ctx_t gctx = NULL;
315			gpgme_data_t in = NULL, out = NULL;
316			recip_list_t list = NULL;
317	twoaday	10	int nkeys=0;
318	twoaday	1	char msg = r_msg;
319
320			assert (ctx);
321
322	twoaday	10	err = get_keys (ctx, &list, &keys, &nkeys);
323			if (err)
324			return err;
325	twoaday	1
326			err = gpgme_new (&gctx);
327			if (!err)
328	twoaday	12	err = create_in_data (&in, msg, ctx->use_utf8);
329	twoaday	1	if (!err)
330			err = gpgme_data_new (&out);
331			if (!err) {
332			gpgme_set_armor (gctx, 1);
333	twoaday	6	gpgme_set_textmode (gctx, 1);
334	twoaday	10	err = gpgme_op_encrypt (gctx, keys,
335			GPGME_ENCRYPT_ALWAYS_TRUST, in, out);
336	twoaday	1	}
337
338			gpgme_release (gctx);
339			gpgme_data_release (in);
340			release_recipient (list);
341			free (keys);
342
343	twoaday	10	if (err)
344	twoaday	1	gpgme_data_release (out);
345	twoaday	10	else
346			map_gpgme_data (out, r_msg);
347			return err;
348	twoaday	1	}
349
350
351	twoaday	10	/* Sign the message given in @r_msg with the GPG default key. */
352	twoaday	1	static gpgme_error_t
353			sign_msg (plugin_ctx_t ctx, char **r_msg)
354			{
355			gpgme_error_t err;
356			gpgme_ctx_t gctx;
357			gpgme_data_t in, out;
358			pass_cb_t cb_val;
359
360			cb_val = new_pass_cb (ctx->main_wnd);
361
362			err = gpgme_new (&gctx);
363			if (!err)
364			err = gpgme_data_new_from_mem (&in, r_msg, strlen (r_msg), 1);
365			if (!err)
366			err = gpgme_data_new (&out);
367			if (!err) {
368			gpgme_set_passphrase_cb (gctx, passphrase_cb, cb_val);
369			err = gpgme_op_sign (gctx, in, out, GPGME_SIG_MODE_CLEAR);
370			}
371
372			gpgme_release (gctx);
373			gpgme_data_release (in);
374			free_pass_cb (cb_val);
375
376	twoaday	10	if (err)
377	twoaday	1	gpgme_data_release (out);
378	twoaday	10	else
379			map_gpgme_data (out, r_msg);
380	twoaday	1
381	twoaday	10	return 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			int ec, nkeys = 0;
396
397			ec = get_keys (ctx, &list, &keys, &nkeys);
398			if (ec)
399			return ec;
400
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			gpgme_release (gctx);
417			gpgme_data_release (in);
418			release_recipient (list);
419			free (keys);
420			free_pass_cb (cb_val);
421
422	twoaday	10	if (err)
423	twoaday	1	gpgme_data_release (out);
424	twoaday	10	else
425			map_gpgme_data (out, r_msg);
426			return err;
427	twoaday	1	}
428
429
430			static gpgme_error_t
431			verify_msg (plugin_ctx_t ctx, char **r_msg)
432			{
433			gpgme_error_t err;
434			gpgme_ctx_t gctx;
435			gpgme_data_t out = NULL;
436			gpgme_data_t sig = NULL;
437			gpgme_verify_result_t res;
438
439			err = gpgme_new (&gctx);
440			if (!err)
441			err = gpgme_data_new_from_mem (&sig, r_msg, strlen (r_msg), 1);
442			if (!err)
443			err = gpgme_data_new (&out);
444			if (!err)
445			err = gpgme_op_verify (gctx, sig, NULL, out);
446			if (!err) {
447			res = gpgme_op_verify_result (gctx);
448			if (res && res->signatures)
449			DialogBoxParam (mod_hinst_dll, (LPCTSTR)IDD_VERIFY, ctx->main_wnd,
450			verify_dlg_proc, (LPARAM)res->signatures);
451			}
452
453			gpgme_release (gctx);
454			gpgme_data_release (sig);
455	twoaday	10
456			if (!err)
457			map_gpgme_data (out, r_msg);
458			else
459			gpgme_data_release (out);
460	twoaday	1	return err;
461			}
462
463
464			/* Detailed error message when the decryption failed. */
465			static void
466			store_decrypt_info (char *buf, size_t buflen,
467			gpgme_decrypt_result_t res)
468			{
469			gpgme_key_t key = NULL;
470			gpgme_ctx_t ctx;
471			int algo;
472
473			if (!res->recipients)
474			return;
475
476			if (!gpgme_new (&ctx)) {
477			gpgme_get_key (ctx, res->recipients->keyid, &key, 0);
478			gpgme_release (ctx);
479			}
480
481			algo = res->recipients->pubkey_algo;
482			if (!key)
483			_snprintf (buf, buflen, _("encrypted with %s key, ID %s\n"
484	twoaday	12	"decryption failed: secret key not available"),
485	twoaday	1	algo == 1? "RSA" : algo==16? "ELG": "???",
486			res->recipients->keyid+8);
487			else {
488			char *uid = utf8_to_native (key->uids->uid);
489			_snprintf (buf, buflen, _("encrypted with %d-bit %s key, ID %s\n"
490			"\t\"%s\"\n"
491	twoaday	12	"decryption failed: secret key not available"),
492	twoaday	1	key->subkeys->length,
493			algo == 1? "RSA" : algo==16? "ELG": "???",
494			key->subkeys->keyid+8, uid);
495			free_if_alloc (uid);
496			}
497			if (key)
498			gpgme_key_release (key);
499			}
500
501
502	twoaday	10	/* Decrypt the message @r_msg. If the type @type is actually a signature,
503			the verify function is called instead of decryption. */
504	twoaday	1	static gpgme_error_t
505			decrypt_msg (plugin_ctx_t ctx, char **r_msg, int type)
506			{
507			gpgme_ctx_t gctx = NULL;
508			gpgme_data_t in = NULL, out = NULL;
509			gpgme_error_t err;
510			gpgme_verify_result_t res;
511			pass_cb_t cb_val;
512			char msg = r_msg;
513
514			if ((type & PGP_SIG) \|\| (type & PGP_CLEARSIG))
515			return verify_msg (ctx, r_msg);
516
517			cb_val = new_pass_cb (ctx->main_wnd);
518
519			err = gpgme_new (&gctx);
520			if (!err)
521			err = gpgme_data_new_from_mem (&in, msg, strlen (msg), 1);
522			if (!err)
523			err = gpgme_data_new (&out);
524			if (!err) {
525			gpgme_set_passphrase_cb (gctx, passphrase_cb, cb_val);
526			err = gpgme_op_decrypt_verify (gctx, in, out);
527			res = gpgme_op_verify_result (gctx);
528			if (res && res->signatures)
529			DialogBoxParam (mod_hinst_dll, (LPCTSTR)IDD_VERIFY, ctx->main_wnd,
530			verify_dlg_proc, (LPARAM)res->signatures);
531			}
532			if (err) {
533			gpgme_decrypt_result_t r = gpgme_op_decrypt_result (gctx);
534			store_decrypt_info (ctx->errbuf, sizeof (ctx->errbuf)-1, r);
535			}
536
537			gpgme_release (gctx);
538			gpgme_data_release (in);
539			free_pass_cb (cb_val);
540
541	twoaday	10	if (err)
542	twoaday	1	gpgme_data_release (out);
543	twoaday	10	else
544			map_gpgme_data (out, r_msg);
545	twoaday	1
546	twoaday	10	return err;
547	twoaday	1	}
548
549
550			/* Return what kind of OpenPGP message @msg is. */
551			static int
552			parse_pgp_id (const char *msg)
553			{
554			int id = 0;
555
556			if (strstr (msg, "BEGIN PGP MESSAGE"))
557			id \|= PGP_MESSAGE;
558			if (strstr (msg, "BEGIN PGP PUBLIC KEY") \|\|
559			strstr (msg, "BEGIN PGP SECRET KEY") \|\|
560			strstr (msg, "BEGIN PGP PRIVATE KEY"))
561			id \|= PGP_KEY;
562			if (strstr (msg, "BEGIN PGP SIGNED MESSAGE"))
563			id \|= PGP_CLEARSIG;
564			return id;
565			}
566
567
568	twoaday	12	static int
569			winpt_key_import (void)
570			{
571			HWND winpt;
572
573			winpt = FindWindow ("WinPT", "WinPT");
574			if (winpt != NULL) {
575			PostMessage (winpt, WM_COMMAND, 40014, 0);
576			return 0;
577			}
578			return -1;
579			}
580
581
582			/* Try to decrypt a PGP/MIME message. */
583			static gpgme_error_t
584			oe_handle_pgp_mime_mail (plugin_ctx_t ctx)
585			{
586			SetEvent (plugin_active);
587
588			/* Select attachment number 0. */
589			AttachThreadInput (GetCurrentThreadId (),
590			GetWindowThreadProcessId (ctx->main_wnd, NULL),
591			TRUE);
592
593			SetFocus (ctx->addr_wnd);
594			SetFocus (ctx->attach);
595			ListView_SetItemState (ctx->attach, 0, LVIS_SELECTED\|LVIS_FOCUSED,
596			LVIS_FOCUSED\|LVIS_SELECTED);
597
598			AttachThreadInput (GetCurrentThreadId (),
599			GetWindowThreadProcessId (ctx->main_wnd, NULL),
600			FALSE);
601
602			SendMessage (ctx->addr_wnd, WM_COMMAND, ID_OE_SAVE_ATT, 0);
603
604			ResetEvent (plugin_active);
605
606			return 0;
607			}
608
609
610	twoaday	1	/* This function can be use for all kind of OE messages.
611			It automatically choose the right procedure to handle the data. */
612			gpgme_error_t
613			oe_handle_mail (plugin_ctx_t ctx)
614			{
615	twoaday	3	gpgme_error_t rc = 0;
616	twoaday	10	char *msg;
617	twoaday	1	int msg_type = 0;
618
619			assert (ctx);
620	twoaday	11
621	twoaday	1	msg = window_get_message (ctx->main_wnd);
622	twoaday	12	#if 0
623			if ((!msg \|\| strlen (msg)) < 2 &&
624			ctx->attach && ListView_GetItemCount (ctx->attach) == 2) {
625			free_if_alloc (msg);
626			return oe_handle_pgp_mime_mail (ctx);
627			}
628			#endif
629	twoaday	1	if (!msg \|\| strlen (msg) == 2) {
630			free_if_alloc (msg);
631			return 0;
632			}
633
634			if (strstr (msg, "-----BEGIN PGP") &&
635			strstr (msg, "-----END PGP"))
636			msg_type = parse_pgp_id (msg);
637
638			if (msg_type & PGP_KEY) {
639	twoaday	12	if (winpt_key_import ())
640			MessageBox (ctx->main_wnd,
641	twoaday	1	_("This mail contains one or more public or secret keys.\n\n"
642			"Please save the mail text in a file to use WinPT to import them."),
643			_("GPG Plug-in Info"), MB_ICONINFORMATION\|MB_OK);
644			}
645			else if (msg_type) {
646			rc = decrypt_msg (ctx, &msg, msg_type);
647			SendMessage (ctx->msg_wnd, WM_CLEAR, 0, 0);
648			SendMessage (ctx->msg_wnd, WM_UNDO, 0, 0);
649			if (!rc && (msg_type & PGP_MESSAGE) && msg && strlen (msg) > 0) {
650			struct viewer_ctx_s viewer;
651			viewer.msg = msg;
652			DialogBoxParam (mod_hinst_dll, (LPCTSTR)IDD_VIEWER, ctx->main_wnd,
653			viewer_dlg_proc, (LPARAM)&viewer);
654			}
655			}
656	twoaday	11	else if (ctx->sign \|\| ctx->encrypt) {
657	twoaday	1	if (!ctx->to && !ctx->cc && !ctx->bcc) {
658			free_if_alloc (msg);
659			return gpg_error (GPG_ERR_NO_DATA);
660			}
661			if (ctx->sign && ctx->encrypt)
662			rc = sign_encrypt_msg (ctx, &msg);
663			else if (ctx->sign)
664			rc = sign_msg (ctx, &msg);
665			else if (ctx->encrypt)
666			rc = encrypt_msg (ctx, &msg);
667			window_set_message (ctx->main_wnd, msg);
668			}
669
670			free_if_alloc (msg);
671			return rc;
672			}