trunk/Src/wptKeylist.cpp

/* wptKeylist.cpp - Keylist element
 *      Copyright (C) 2001-2006 Timo Schulz
 *      Copyright (C) 2004 Andreas Jobs
 *
 * This file is part of WinPT.
 *
 * WinPT is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License 
 * as published by the Free Software Foundation; either version 2 
 * of the License, or (at your option) any later version.
 *  
 * WinPT is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License 
 * along with WinPT; if not, write to the Free Software Foundation, 
 * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <windows.h>
#include <commctrl.h>
#include <time.h>

#include "wptCommonCtl.h"
#include "wptTypes.h"
#include "wptGPG.h"
#include "wptKeylist.h"
#include "wptKeyManager.h"
#include "wptW32API.h"
#include "wptNLS.h"
#include "wptErrors.h"
#include "wptUTF8.h"
#include "wptRegistry.h"
#include "wptContext.h"
#include "wptVersion.h"
#include "resource.h"

#define key_is_useable(key) (!(key)->revoked && !(key)->expired && !(key)->disabled)

struct key_array_s {
    char keyid[32];
    int checked;
};

static int find_secret_key (gpgme_key_t key);


static key_array_s*
key_array_new (int items)
{
    key_array_s *ka;
    int j;
    
    if (items == 0)
        return NULL;
    ka = new key_array_s[items + 1];
    if (!ka)
        BUG (NULL);
    for (j = 0; j < items; j++)
        ka[j].checked = 0;
    return ka;
}


static void
key_array_release (key_array_s *ka)
{
    free_if_alloc (ka);
}


/* Check if the keyid @keyid is in the key array @ka.
   Return value: 1 if it exists, 0 otherwise. */
static int
key_array_search (key_array_s *ka, int items, const char *keyid)
{
    int j;
    
    for (j = 0; j < items; j++) {
        if (!strcmp (keyid, ka[j].keyid ))
            return 1;   
    }
    return 0;
}


gpgme_user_id_t
get_nth_userid (gpgme_key_t key, int idx)
{
    gpgme_user_id_t t;

    if (!key->uids)
        return NULL;
    t = key->uids;
    while (idx-- && t->next)
        t = t->next;
    return t;
}


int
count_userids (gpgme_key_t key)
{
    gpgme_user_id_t u;
    int n = 1;

    u = key->uids;
    if (!u)
        return 0;
    while (u->next) {
        u = u->next;
        n++;
    }
    return n;
}


gpgme_subkey_t
get_nth_key (gpgme_key_t key, int idx)
{
    gpgme_subkey_t t;

    if (!key->subkeys)
        return NULL;
    t = key->subkeys;
    while (idx-- && t->next)
        t = t->next;
    return t;
}


int
count_subkeys (gpgme_key_t key)
{
    gpgme_subkey_t k;
    int n = 1;

    k = key->subkeys;
    if (!k)
        return 0;
    while (k->next) {
        k = k->next;
        n++;
    }
    return n;
}


/* Return the self signature of the key @keyid.
   If first is set, the first self sig will be returned. */
gpgme_key_sig_t
get_selfsig (gpgme_user_id_t uid, const char *keyid, int first)
{
    gpgme_key_sig_t s, self_sig=NULL;
    long timestamp=0;
    int off = 0;

    if (strlen (keyid) == 8)
        off = 8;

    for (s = uid->signatures; s; s = s->next) {
        if (!strcmp (s->keyid+off, keyid) && s->timestamp > timestamp) {
            self_sig = s;
            timestamp = s->timestamp;
            if (first)
                break;
        }
    }
    return self_sig;
}


const char*
get_key_algo (gpgme_key_t key, int keyidx)
{
    static char algo_id[128];
    gpgme_subkey_t k;
    char alg[32];
    const char *subalg;
    int n=0;
    
    if (keyidx > 0) {
        k = get_nth_key (key, keyidx-1);
        subalg =  get_key_pubalgo (k->pubkey_algo);
        _snprintf (algo_id, DIM (algo_id)-1, "%s", subalg);
        return algo_id;
    }
    strcpy (alg, get_key_pubalgo (key->subkeys->pubkey_algo));
    n = count_subkeys (key);
    if (n > 1) {
        k = get_nth_key (key, n-1);
        subalg = get_key_pubalgo (k->pubkey_algo);
        _snprintf (algo_id, DIM (algo_id)-1, "%s/%s", alg, subalg);
        return algo_id;
    }
    return get_key_pubalgo (key->subkeys->pubkey_algo);
}


const char*
get_key_created (long timestamp)
{
    static char timebuf[128];
    struct tm *warp;
    const char *dat;

    if (timestamp < 1)
        return "????" "-??" "-??";
    dat = get_locale_date (timestamp, timebuf, sizeof (timebuf)-1);
    if (dat)
        return dat;
    warp = localtime (&timestamp);
    _snprintf (timebuf, sizeof timebuf - 1, "%04d-%02d-%02d",
               warp->tm_year + 1900, warp->tm_mon + 1, warp->tm_mday);
    return timebuf;
}


/* Return a string presentation of the time @timestamp. */
const char*
get_key_expire_date (long timestamp)
{
    static char timebuf[64];
    struct tm *warp;
    const char *dat;

    if (timestamp == 0)
        return _("Never");
    dat = get_locale_date (timestamp, timebuf, sizeof (timebuf)-1);
    if (dat)
        return dat;
    warp = localtime (&timestamp);
    _snprintf (timebuf, sizeof timebuf -1, "%04d-%02d-%02d",
               warp->tm_year + 1900, warp->tm_mon + 1, warp->tm_mday);
    return timebuf;
}


const char*
get_key_type (gpgme_key_t key)
{
    int type = find_secret_key (key);

    if (type == 1)
        return _("Key Pair");
    else if (type == 2)
        return _("Key Pair (Card)");
    return _("Public Key");
}


const char*
get_key_size (gpgme_key_t key, int keyidx)
{
    static char size_id[64];
    gpgme_subkey_t k;
    int n, size_main, size_sub;
    
    if (keyidx > 0) {
        k = get_nth_key (key, keyidx-1);
        size_main = k->length;
        _snprintf (size_id, DIM (size_id)-1, "%d", size_main);
        return size_id;
    }
    size_main =  key->subkeys->length;
    n = count_subkeys (key);
    if (n > 1) {
        k = get_nth_key (key, n-1);
        size_sub = k->length;
        _snprintf (size_id, sizeof (size_id) - 1, "%d/%d", 
                    size_main, size_sub);
        return size_id; 
    }
    _snprintf( size_id, sizeof (size_id) - 1, "%d", size_main );
    return size_id;
}


const char*
get_key_pubalgo2 (gpgme_pubkey_algo_t alg)
{
    switch (alg) {
    case GPGME_PK_DSA: return "D";
    case GPGME_PK_RSA: return "R";
    case GPGME_PK_ELG: return "G";
    default: return "?";
    }
    return "?";
}


const char*
get_key_pubalgo (gpgme_pubkey_algo_t alg)
{
    switch (alg) {
    case GPGME_PK_DSA: return "DSA";
    case GPGME_PK_ELG:
    case GPGME_PK_ELG_E: return "ELG";
    case GPGME_PK_RSA: return "RSA";
    default: return "???";
    }
    return "???";
}

const char*
get_key_fpr (gpgme_key_t key)
{
    static char fpr_md[64];
    const char *fpr;
    char t[16], tmp[40];
    size_t i=0;
    
    memset (fpr_md, 0, sizeof (fpr_md));
    fpr = key->subkeys->fpr;
    if (!fpr || !*fpr) {
        memset (tmp, '0', 40);
        fpr = tmp;
    }
    if (strlen (fpr) == 32) {
        strcat (fpr_md, "        ");
        for (i=0; i < strlen (fpr)/2; i++) {
            sprintf (t, "%c%c ", fpr[2*i], fpr[2*i+1]);
            strcat (fpr_md, t);
        }
    }
    else {
        strcat (fpr_md, " ");
        for (i = 0; i < strlen (fpr) / 4; i++) {
            sprintf (t, "%c%c%c%c ", fpr[4*i], fpr[4*i+1], fpr[4*i+2], fpr[4*i+3]);
            strcat (fpr_md, t);
        }
    }
    return fpr_md;
}


const char*
get_key_trust2 (gpgme_key_t key, int val, int uididx, int listmode)
{
    if (key)
        val = key->owner_trust; /* uididx?? */
    switch (val) {
    case GPGME_VALIDITY_UNKNOWN:
    case GPGME_VALIDITY_UNDEFINED:    
        return _("None");
    case GPGME_VALIDITY_NEVER:    
        return _("Never");
    case GPGME_VALIDITY_MARGINAL:
        return _("Marginal");
    case GPGME_VALIDITY_FULL:
    case GPGME_VALIDITY_ULTIMATE:
        return _("Full");
    }
    return "";
}


const char*
get_key_trust (gpgme_key_t key, int uididx, int listmode)
{
    return get_key_trust2 (key, 0, uididx, listmode);
}


const char*
get_key_trust_str (int val)
{
    return get_key_trust2 (NULL, val, 0, 0);
}


/* Return the status of the key @key. */
char*
get_key_status (gpgme_key_t key, int uididx, int listmode)
{
    gpgme_user_id_t u;
    const char *attr;
    u32 key_attr =0;

    if (uididx < 0 || count_userids (key) > uididx)
        uididx = 0;
    if (listmode) {
        const char *s;
        if (key->revoked)
            s = _("Revoked");
        else if (key->expired)
            s = _("Expired");
        else if (key->disabled)
            s = _("Disabled");
        else
            s = "";
        /* if the key has a special status, we don't continue to figure out
           the user-id validities. */
        if (*s)
            return m_strdup (s);
    }
    u = get_nth_userid (key, uididx);
    key_attr = u->validity;
    attr = get_key_trust2 (NULL, key_attr, 0, 0);
    return m_strdup (attr);
}


/* Return human readable description of the key @key. */
char*
get_key_desc (gpgme_key_t key)
{
    gpgme_key_t sk;
    const char *state, *alg, *type;
    char *p;

    /* XXX: problems with the German translation. */
    state = "";
    if (key->disabled)
        state = _("Disabled");
    if (key->expired)
        state = _("Expired");
    if (key->revoked)
        state = _("Revoked");
    alg = "OpenPGP";
    if (strlen (key->subkeys->fpr) == 32)
        alg = "RSA Legacy";
    type = _("public key");
    if (!get_seckey (key->subkeys->keyid+8, &sk))
        type = _("key pair");
    p = new char[strlen (state) + strlen (alg) + strlen (type) + 4 + 1];
    if (!p)
        BUG (0);
    sprintf (p, "%s %s %s", state, alg, type);
    return p;
}


/* Integer comparsion of @a and @b. 
   Return values: same as in strcmp. */
static inline int
int_cmp (int a, int b)
{
    if (a == b) return 0;       
    else if (a > b) return 1;
    else return -1;
    return 0;
}


/* To allow to sort the keys, we need to take care of
   the expired/revoke status also. */
static int
get_ext_validity (gpgme_key_t k)
{
    if (k->revoked)
        return GPGME_VALIDITY_ULTIMATE+1;
    else if (k->expired)
        return GPGME_VALIDITY_ULTIMATE+2;
    else if (k->disabled)
        return GPGME_VALIDITY_ULTIMATE+3;
    return k->uids->validity;
}


/* List view sorting callback. */
static int CALLBACK
keylist_cmp_cb (LPARAM first, LPARAM second, LPARAM sortby)
{
    gpgme_key_t a, b;
    int cmpresult = 0;
    
    a = (gpgme_key_t)first;
    b = (gpgme_key_t)second;
    if (!a || !b)
        BUG (NULL);
    
    switch (sortby & ~KEYLIST_SORT_DESC) {
    case KEY_SORT_USERID:
        cmpresult = strcmpi (a->uids->uid, b->uids->uid);
        break;
        
    case KEY_SORT_KEYID:
        cmpresult = strcmpi (a->subkeys->keyid+8,
                             b->subkeys->keyid+8);
        break;

    case KEY_SORT_VALIDITY:
        cmpresult = int_cmp (get_ext_validity (a), 
                             get_ext_validity (b));
        break;

    case KEY_SORT_OTRUST:
        cmpresult = int_cmp (a->owner_trust, b->owner_trust);
        break;

    case KEY_SORT_IS_SECRET:
        get_seckey (a->subkeys->keyid, &a);
        get_seckey (b->subkeys->keyid, &b);
        cmpresult = int_cmp (a? a->secret : 0, b? b->secret : 0);
        break;

    case KEY_SORT_LEN:
        cmpresult = int_cmp (a->subkeys->length, 
                             b->subkeys->length);
        break;

    case KEY_SORT_CREATED:
        cmpresult = int_cmp (a->subkeys->timestamp, 
                             b->subkeys->timestamp);
        break;

    case KEY_SORT_ALGO:
        cmpresult = int_cmp (a->subkeys->pubkey_algo,
                             b->subkeys->pubkey_algo);
        break;
        
    default:
        cmpresult = strcmpi (a->uids->uid, b->uids->uid);
        break;
    }
    if (sortby & KEYLIST_SORT_DESC)
        return (~cmpresult + 1);
    else
        return cmpresult;
}


int
keylist_add_groups (listview_ctrl_t lv)
{
    return 0;
}


/* Create a listview for listing keys. Use the mode given in @mode
   and the control is given in @ctrl. */
static int
keylist_build (listview_ctrl_t *r_lv, HWND ctrl, int mode)
{
    struct listview_column_s klist_enc[] = {
    {0, 242, (char *)_("User ID")},
    {1, 80, (char *)_("Key ID")},
    {3, 46, (char *)_("Size")},
    {4, 50, (char *)_("Cipher")},
    {5, 70, (char *)_("Validity")},
    {0, 0, NULL}
    };
    struct listview_column_s klist[] = {
    {0, 240, (char *)_("User ID")},
    {1, 78, (char *)_("Key ID")},
    {2, 52, (char *)_("Type")},    
    {3, 66, (char *)_("Size")},
    {4, 60, (char *)_("Cipher")},
    {5, 66, (char *)_("Validity")},
    {6, 58, (char *)_("Trust")},
    {7, 72, (char *)_("Creation")},
    {0, 0, NULL}
    };
    HICON ico[2];
    listview_ctrl_t lv;
    listview_column_t col;
    int j, n = 0, ext_chk = 0;
    int rc = 0;
    
    rc = listview_new (&lv);
    if (rc)
        return rc;
    
    lv->ctrl = ctrl;
    if (mode & KEYLIST_ENCRYPT_MIN) {
        col = klist_enc;
        n = (DIM(klist_enc) -1);
        ext_chk = 1;
    }   
    else if ((mode & KEYLIST_SIGN)) {
        col = klist_enc;
        n = (DIM(klist_enc) - 1) - 1;
        ext_chk = 1;
    }
    else {
        col = klist;
        n = (DIM(klist) - 1);
    }
    
    for (j = 0; j < n; j++)
        listview_add_column (lv, &col[j]);    
    listview_set_ext_style (lv);
    if (ext_chk)
        listview_set_chkbox_style (lv);
    ico[0] = LoadIcon (glob_hinst, (LPCTSTR)IDI_PUBKEY);
    ico[1] = LoadIcon (glob_hinst, (LPCTSTR)IDI_KEYPAIR);
    listview_set_image_list (lv, 22, 14, ico, 2);
    listview_del_all_items (lv);

    *r_lv = lv;
    return 0;
}


static void
keylist_load_keycache (listview_ctrl_t lv, int mode, 
                       gpg_keycache_t pubkc, gpg_keycache_t seckc)
{
    gpgme_error_t err = gpg_error (GPG_ERR_NO_ERROR);
    gpgme_key_t key, skey;
    const char * keyid;

    if (pubkc && seckc) {
        gpg_keycache_rewind (pubkc);
        while (!gpg_keycache_next_key (pubkc, 0, &key)) {
            keyid = key->subkeys->keyid;
            if (keyid && !gpg_keycache_find_key (seckc, keyid, 0, &skey))
                keylist_add_key (lv, mode, key);
        }       
    }
    else if (pubkc) {
        gpg_keycache_rewind (pubkc);
        while (!err) {    
            err = gpg_keycache_next_key (pubkc, 0, &key);
            if (!err)
                keylist_add_key (lv, mode, key);
        }
    }
}


/* Load the list view @ctrl with the keys from the cache.
   Return value: list view context on success. */
listview_ctrl_t
keylist_load (HWND ctrl, gpg_keycache_t pubkc, gpg_keycache_t seckc, 
              int mode, int sortby)
{    
    listview_ctrl_t lv;
    int rc = 0;    

    rc = keylist_build (&lv, ctrl, mode);
    if (rc)
        return NULL;            
    keylist_load_keycache (lv, mode, pubkc, seckc);
    keylist_sort (lv, sortby);
    if (mode & KEYLIST_ENCRYPT_MIN)
        keylist_add_groups (lv);
    return lv;
}


/* Reload the given key list control @lv. */
int
keylist_reload (listview_ctrl_t lv, gpg_keycache_t pubkc, int mode, int sortby)
{
    listview_del_all_items (lv);
    keylist_load_keycache (lv, mode, pubkc, NULL);
    keylist_sort (lv, sortby);
    return 0;
}


void
keylist_delete (listview_ctrl_t lv)
{
    if (lv) {
        listview_release (lv);
    }
}


/* Return if there is a secret for @key.
   0 means success. */
static int
find_secret_key (gpgme_key_t key)
{
    const char *keyid;
    winpt_key_s skey;
    
    memset (&skey, 0, sizeof (skey));
    keyid = key->subkeys->keyid;
    if (!keyid)
        return 0;
    winpt_get_seckey (keyid, &skey);
    if (skey.ext && skey.ext->gloflags.divert_to_card)
        return 2;
    return skey.ctx? 1 : 0;
}


static int
do_addkey (listview_ctrl_t lv, gpgme_key_t key, int uididx, int keyidx, int list)
{    
    LV_ITEM lvi;
    gpgme_user_id_t u;
    gpgme_subkey_t k;
    char fmt[128], *p;
    const char *attr;
    u32 key_attr;
    int idx = 0;    

    /* we check the pubkey algorithm here to make sure that no ElGamal
       sign+encrypt key is used in _any_ mode */
    if (list != 1 && key->subkeys->pubkey_algo == GPGME_PK_ELG) {
        log_debug ("ElGamal (E+S) key found: %s (%s)\n",
                   key->uids->name, key->subkeys->keyid);
        return 0;
    }
        
    if (listview_add_item2 (lv, " ", (void *)key))
        return WPTERR_GENERAL;

    attr = key->uids->uid;
    memset (&lvi, 0, sizeof lvi);
    lvi.mask = LVIF_TEXT | LVIF_PARAM | LVIF_IMAGE;
    lvi.pszText = (char *)attr;
    lvi.iImage = find_secret_key (key)? 1 : 0;
    lvi.lParam = (LPARAM )key;
    if (ListView_SetItem (lv->ctrl, &lvi) == FALSE)
        return WPTERR_GENERAL;
        
    if (uididx == -1) { /* request the primary user-id of the key. */
        attr = key->uids->uid;
        uididx = 0;
    }
    else {
        u = get_nth_userid (key, uididx);
        if (!u || u->revoked || uididx < 0)
            uididx = 0;
        u = get_nth_userid (key, uididx);
        attr = u->uid;
    }
    if (attr == NULL || strlen (attr) < 5) { /* normal userids are > 5 chars */
        attr = _("Invalid User ID");
        listview_add_sub_item (lv, 0, idx++, attr);
    }   
    else {
        char *uid = utf8_to_wincp (attr, strlen (attr));
        if (uid) {
            listview_add_sub_item (lv, 0, idx++, uid);
            free (uid);
        }
    }
    k = get_nth_key (key, keyidx);
    if (k && k->keyid) {
        _snprintf (fmt, sizeof fmt -1, "0x%s", k->keyid + 8);
        listview_add_sub_item( lv, 0, idx++, fmt );
    }
    if (list > 0) {
        key_attr = find_secret_key (key);
        if (!key_attr)
            attr = "pub";
        else
            attr = key_attr == 1? "pub/sec" : "pub/crd";
        listview_add_sub_item (lv, 0, idx++, attr);
    }
    if (lv->cols >= 2) {
        attr = get_key_size (key, list == -1? keyidx+1 : 0);
        if (attr)
            listview_add_sub_item (lv, 0, idx++, attr);
    }
    if (lv->cols >= 3) {
        attr = get_key_algo (key, list == -1? keyidx+1 : 0);
        if (attr) 
            listview_add_sub_item( lv, 0, idx++, attr);
    }
    if (lv->cols >= 4) {
        p = get_key_status( key, uididx, list > 0? 1 : 0 );
        if (!p)
            return WPTERR_GENERAL;
        listview_add_sub_item (lv, 0, idx++, p);
        free_if_alloc (p);
    }
    if (lv->cols >= 5) {
        attr = get_key_trust (key, uididx, list > 0? 1 : 0);
        listview_add_sub_item (lv, 0, idx++, attr);
    }
    if( lv->cols >= 6 ) {
        k = get_nth_key (key, keyidx);
        key_attr = k->timestamp;
        if( key_attr ) {
            attr = get_key_created (key_attr);
            listview_add_sub_item( lv, 0, idx++, attr );
        }       
    }

    return 0;
}


/* Update a single column @col but for each element in the
   listview @lv. */
void
keylist_upd_col (listview_ctrl_t lv, int col)
{
    gpgme_key_t key;
    const char *s;
    char buf[32], *p;
    int i;

    for (i=0; i < listview_count_items (lv, 0); i++) {
        key = (gpgme_key_t)listview_get_item2 (lv, i);
        if (!key)
            continue;
        switch (col) {
        case KM_COL_KEYID:
            _snprintf (buf, sizeof (buf)-1, "0x%s", key->subkeys->keyid+8);
            listview_add_sub_item (lv, i, col, buf);
            break;

        case KM_COL_CIPHER:
            s = get_key_algo (key, 0);
            listview_add_sub_item (lv, i, col, s);
            break;

        case KM_COL_TYPE:
            s = find_secret_key (key)? "pub/sec" : "pub";
            listview_add_sub_item (lv, i, col, s);
            break;

        case KM_COL_CREAT:
            s = get_key_created (key->subkeys->timestamp);
            listview_add_sub_item (lv, i, col, s);
            break;

        case KM_COL_DESC:
            p = get_key_desc (key);
            listview_add_sub_item (lv, i, col, p);
            free_if_alloc (p);
            break;
        }
    }
}


/* Update the listview item at position @pos with the data from
   the key @key. */
void
keylist_upd_key (listview_ctrl_t lv, int pos, gpgme_key_t key)
{
    const char *s;
    char *uid, *p;
    char tmp[32];

    listview_set_item2 (lv, pos, (void *)key);
    /* the only mode we support is KYLIST_LIST in the Key Manager */
    
    s = key->uids->uid;
    if (s) {
        uid = utf8_to_wincp2 (s);
        listview_add_sub_item (lv, pos, KM_COL_UID, uid);
        free (uid);
    }

    s = key->subkeys->keyid;
    if (s) {
        sprintf (tmp, "0x%s", s+8);
        listview_add_sub_item (lv, pos, KM_COL_KEYID, tmp);
    }

    s = find_secret_key (key)? "pub/sec" : "pub";
    listview_add_sub_item (lv, pos, KM_COL_TYPE, s);

    s = get_key_size (key, 0);
    if (s)
        listview_add_sub_item (lv, pos, KM_COL_SIZE, s);

    s = get_key_algo (key, 0);
    if (s)
        listview_add_sub_item (lv, pos, KM_COL_CIPHER, s);

    p = get_key_status (key, 0, 1);
    if (p) {
        listview_add_sub_item (lv, pos, KM_COL_VALID, p);
        free_if_alloc (p);
    }

    s = get_key_trust (key, 0, 1);
    if (s)
        listview_add_sub_item (lv, pos, KM_COL_TRUST, s);

    long t = key->subkeys->timestamp;
    s = get_key_created (t);
    if (s)
        listview_add_sub_item (lv, pos, KM_COL_CREAT, s);
}


int
keylist_add_key (listview_ctrl_t lv, int mode, gpgme_key_t key)
{
    int uids, rc = 0, i;
    gpgme_subkey_t k;

    /* if the entire key is disabled, just return. */
    if (key->disabled && !(mode & KEYLIST_LIST))
        return 0;

    for (k=key->subkeys, i = 0; i < count_subkeys (key); i++, k=k->next) {
        if (k->invalid) {
            log_debug ("keylist_add_key: invalid key \"%s\"\n", key->uids->name);
            continue; /* Don't use invalid keys */
        }

        if (mode & KEYLIST_ALL) {
            uids = count_userids (key);
            rc = do_addkey (lv, key, uids, i, 0);
            if (rc)
                return rc;
        }
        else if (mode & KEYLIST_LIST)
            return do_addkey (lv, key, -1, i, 1);
        else if (mode & KEYLIST_ENCRYPT) {
            if (k->can_encrypt && key_is_useable (k)) {
                if (mode & KEYLIST_FLAG_FILE) {
                    rc = do_addkey (lv, key, -1, i, -1);
                    if (rc)
                        return rc;
                }
                else {
                    for (uids = 0;  uids < count_userids (key); uids++) {
                        rc = do_addkey (lv, key, uids, i, -1);
                        if (rc)
                            return rc;
                    }
                }
            }
        }
        else if (mode & KEYLIST_ENCRYPT_MIN) {
            if( k->can_encrypt && key_is_useable (k))
            {
                rc = do_addkey (lv, key, -1, i, -1);
                return rc;
            }
        }       
        else if (mode & KEYLIST_SIGN) {
            if (k->can_sign 
                && find_secret_key (key)
                && key_is_useable (k)) {
                rc = do_addkey (lv, key, -1, i, -1);
                if (rc)
                    return rc;  
            }
        }       
    }

    return rc;  
}


int
keylist_sort (listview_ctrl_t lv, int sortby)
{
    return listview_sort_items (lv, sortby, keylist_cmp_cb);
}


/* Check that the validity @validity is at least >= marginal. */
static int
key_check_validity (gpgme_key_t key)
{
    gpgme_user_id_t u;

    for (u=key->uids; u; u =u->next) {
        if (u->validity >= GPGME_VALIDITY_MARGINAL)
            return -1;
    }

    return 0;
}


/* Extract all selected recipients from the list @lv and return them 
   as a vector. @r_force_trust is >= 1 if one of the recipients is not
   fully trusted. @r_count returns the number of selected keys.
   Return value: the key list on success, NULL otherwise. */
gpgme_key_t*
keylist_get_recipients (listview_ctrl_t lv, int *r_force_trust, int *r_count)
{
    key_array_s *ka = NULL;
    gpgme_key_t *keybuf, key;
    int count = 0, force_trust = 0;
    int n, j, ka_pos = 0, rc = 0;
    int k_pos=0;

    n = listview_count_items (lv, 0);
    
    ka = key_array_new (n);
    if (!ka)
        BUG (NULL);

    keybuf = (gpgme_key_t*)calloc (n, sizeof (gpgme_key_t));
    if (!keybuf)
        BUG (NULL);
        
    for (j = 0; j < n; j++) {
        if (listview_get_item_state (lv, j) || n == 1) {
            key = (gpgme_key_t)listview_get_item2 (lv, j);
            if (!key)
                BUG (0);
            if (!key_check_validity (key) &&
                !key_array_search (ka, ka_pos, key->subkeys->keyid)) {
                char *warn = new char[512+strlen (key->uids->uid) + 1];
                if (!warn)
                    BUG (0);
                sprintf (warn,
                    _("It is NOT certain that the key belongs to the person\n"
                      "named in the user ID.  If you *really* know what you are\n"
                      "doing, you may answer the next question with yes\n"
                      "\n"
                      "Use \"%s\" anyway?"), key->uids->uid);
                if (reg_prefs.always_trust)
                    rc = IDYES;
                else
                    rc = msg_box (NULL, warn, _("Recipients"), MB_ERR_ASK);
                if (rc == IDYES) {
                    keybuf[k_pos++] = key;
                    force_trust++;
                    ka[ka_pos].checked = 1;
                    strcpy (ka[ka_pos++].keyid, key->subkeys->keyid);
                    count++;
                }
                free_if_alloc (warn);
            }
            else {
                keybuf[k_pos++] = key;
                count++;        
            }
        }
    }
    key_array_release (ka);
    if (r_force_trust)
        *r_force_trust = force_trust;
    if (r_count)
        *r_count = count;
    return keybuf;
}


static int
keylist_get_keyflags (gpgme_key_t key)
{
    int flags = KEYFLAG_NONE;

    if (key->revoked)
        flags |= KEYFLAG_REVOKED;
    if (key->expired)
        flags |= KEYFLAG_EXPIRED;
    if (key->disabled)
        flags |= KEYFLAG_DISABLED;

    return flags;
}


gpgme_key_t*
keylist_enum_recipients (listview_ctrl_t lv,  int listype, int *r_count)
{
    gpgme_key_t *rset;
    gpgme_key_t key;
    int i, n, id, k_pos=0;

    n = listview_count_items (lv, 0);
    if (!n)
        return 0;
    rset = (gpgme_key_t*)calloc (n, sizeof (gpgme_key_t));
    if (!rset)
        BUG (NULL);
    for (i = 0; i < n; i++) {
        if (!listview_get_item_state (lv, i))
            continue;
        key = (gpgme_key_t)listview_get_item2 (lv, i);
        if (!key)
            BUG (0);
        switch (listype) {
        case KEYLIST_LIST:
            if (keylist_get_keyflags (key) & KEYFLAG_REVOKED) {
                id = printf_box (_("Recipients"), MB_INFO|MB_YESNO,
                _("KeyID %s.\nDo you really want to export a revoked key?"),
                                 key->uids->uid);
                if (id == IDNO)
                    continue;
            }
            break;
        }
        rset[k_pos++] = key;
    }
    if (r_count)
        *r_count = k_pos;
    return rset;
}


void
seclist_destroy (keylist_t *list)
{
    keylist_t l2;
    while (*list) {
        l2 = (*list)->next;
        safe_free (*list);
        *list = l2;     
    }
    list = NULL;
}


void
seclist_init (HWND dlg, int ctlid, int flags, keylist_t * ret_list)
{    
    gpg_keycache_t kc = NULL;
    gpgme_key_t key = NULL;
    HWND kb;
    keylist_t list=NULL, l, l2;    
    long pos = 0;

    SendDlgItemMessage (dlg, ctlid, CB_RESETCONTENT, 0, 0);
    kb = GetDlgItem (dlg, ctlid);
    kc = keycache_get_ctx (0);
    if (!kc)
        BUG (0);
    gpg_keycache_rewind (kc);
    
    while (!gpg_keycache_next_key (kc, 1, &key)) {
        char *inf = NULL, *uid = NULL;
        const char *id;
        const char *keyid;
        int algo;
        size_t size = 0;

        if (flags & KEYLIST_FLAG_SHORT)
            id = key->uids->name;
        else
            id = key->uids->uid;
        keyid = key->subkeys->keyid;
        algo = key->subkeys->pubkey_algo;
        if (!id || !keyid)
            continue;
        if (key->disabled || !key_is_useable (key->subkeys))
            continue;

        uid = utf8_to_wincp (id, strlen (id));
        size = strlen (uid) + strlen (keyid) + 32;
        inf = new char[size+1];
        if (!inf)
            BUG (NULL);
        _snprintf (inf, size, "%s (%s/0x%s)", uid,
                   get_key_pubalgo (key->subkeys->pubkey_algo), keyid + 8);
        combox_add_string (kb, inf);
        free_if_alloc (inf);
        free (uid);
        l = (struct keylist_s *)calloc (1, sizeof * l);
        if (!l)
            BUG (0);
        l->key = key;
        if (!list)
            list = l;
        else {
            for( l2 = list; l2->next; l2 = l2->next )
                ;
            l2->next = l;
        }
    }
    for (pos = 0, l2=list; pos < SendMessage (kb, CB_GETCOUNT, 0, 0); 
         pos++, l2=l2->next)
        SendMessage (kb, CB_SETITEMDATA, pos, (LPARAM)(DWORD)l2->key);
    SendMessage (kb, CB_SETCURSEL, 0, 0);
    *ret_list = list;
}
        

/* Select a secret key from the combo box with the ID @ctlid.
   Return the code on success in @ret_key. */
int
seclist_select_key (HWND dlg, int ctlid, gpgme_key_t *ret_key)
{
    int pos;
    DWORD k = 0;

    pos = SendDlgItemMessage (dlg, ctlid, CB_GETCURSEL, 0, 0);
    if (pos == CB_ERR) {
        msg_box (dlg, _("No key was selected."), _("Secret Key List"), MB_ERR);
        *ret_key = NULL;
    }
    else {
        k = SendDlgItemMessage (dlg, ctlid, CB_GETITEMDATA, pos, 0);
        *ret_key = (gpgme_key_t)k;
    }
    return k? 0 : -1; 
}