gpgme/trunk/gpgme/encrypt.c

/* encrypt.c -  encrypt functions
 *	Copyright (C) 2000 Werner Koch (dd9jn)
 *      Copyright (C) 2001 g10 Code GmbH
 *
 * This file is part of GPGME.
 *
 * GPGME 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.
 *
 * GPGME 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 this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
 */

#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>

#include "util.h"
#include "context.h"
#include "ops.h"

#define SKIP_TOKEN_OR_RETURN(a) do { \
    while (*(a) && *(a) != ' ') (a)++; \
    while (*(a) == ' ') (a)++; \
    if (!*(a)) \
        return; /* oops */ \
} while (0)

struct encrypt_result_s
{
  int no_recipients;
  GpgmeData xmlinfo;
};

void
_gpgme_release_encrypt_result (EncryptResult result)
{
  if (!result)
    return;
  gpgme_data_release (result->xmlinfo);
  xfree (result);
}

/* 
 * Parse the args and save the information 
 * in an XML structure.
 * With args of NULL the xml structure is closed.
 */
static void
append_xml_encinfo (GpgmeData *rdh, char *args)
{
    GpgmeData dh;
    char helpbuf[100];

    if ( !*rdh ) {
        if (gpgme_data_new (rdh)) {
            return; /* fixme: We are ignoring out-of-core */
        }
        dh = *rdh;
        _gpgme_data_append_string (dh, "<GnupgOperationInfo>\n");
    }
    else {
        dh = *rdh;
        _gpgme_data_append_string (dh, "  </encryption>\n");
    }

    if (!args) { /* just close the XML containter */
        _gpgme_data_append_string (dh, "</GnupgOperationInfo>\n");
        return;
    }

    _gpgme_data_append_string (dh, "  <encryption>\n"
                                   "    <error>\n"
                                   "      <invalidRecipient/>\n");
    
    sprintf (helpbuf, "      <reason>%d</reason>\n", atoi (args));
    _gpgme_data_append_string (dh, helpbuf);
    SKIP_TOKEN_OR_RETURN (args);

    _gpgme_data_append_string (dh, "      <name>");
    _gpgme_data_append_percentstring_for_xml (dh, args);
    _gpgme_data_append_string (dh, "</name>\n"
                                   "    </error>\n");
}





static void
encrypt_status_handler (GpgmeCtx ctx, GpgStatusCode code, char *args)
{
    if (ctx->out_of_core)
      return;
    if (!ctx->result.encrypt)
      {
        ctx->result.encrypt = xtrycalloc (1, sizeof *ctx->result.encrypt);
        if (!ctx->result.encrypt)
	  {
            ctx->out_of_core = 1;
            return;
	  }
      }

    switch (code) {
      case STATUS_EOF:
        if (ctx->result.encrypt->xmlinfo) {
            append_xml_encinfo (&ctx->result.encrypt->xmlinfo, NULL);
            _gpgme_set_op_info (ctx, ctx->result.encrypt->xmlinfo);
            ctx->result.encrypt->xmlinfo = NULL;
        }
        break;

      case STATUS_INV_RECP:
        append_xml_encinfo (&ctx->result.encrypt->xmlinfo, args);
        break;

      case STATUS_NO_RECP:
        ctx->result.encrypt->no_recipients = 1; /* i.e. no usable ones */
        break;

      default:
        break;
    }

}



GpgmeError
gpgme_op_encrypt_start ( GpgmeCtx c, GpgmeRecipients recp,
                         GpgmeData plain, GpgmeData ciph )
{
    int rc = 0;
    int i;

    fail_on_pending_request( c );
    c->pending = 1;

    _gpgme_release_result (c);
    c->out_of_core = 0;

    /* do some checks */
    if ( !gpgme_recipients_count ( recp ) ) {
        /* Fixme: In this case we should do symmentric encryption */
        rc = mk_error (No_Recipients);
        goto leave;
    }
        
    /* create a process object */
    _gpgme_gpg_release (c->gpg); c->gpg = NULL;
    rc = _gpgme_gpg_new ( &c->gpg );
    if (rc)
        goto leave;

    _gpgme_gpg_set_status_handler ( c->gpg, encrypt_status_handler, c );

    /* build the commandline */
    _gpgme_gpg_add_arg ( c->gpg, "--encrypt" );
    if ( c->use_armor )
        _gpgme_gpg_add_arg ( c->gpg, "--armor" );
    for ( i=0; i < c->verbosity; i++ )
        _gpgme_gpg_add_arg ( c->gpg, "--verbose" );
    /* If we know that all recipients are valid (full or ultimate trust)
     * we can suppress further checks */
    if ( _gpgme_recipients_all_valid (recp) )
        _gpgme_gpg_add_arg ( c->gpg, "--always-trust" );
    
    _gpgme_append_gpg_args_from_recipients ( recp, c->gpg );

    /* Check the supplied data */
    if ( gpgme_data_get_type (plain) == GPGME_DATA_TYPE_NONE ) {
        rc = mk_error (No_Data);
        goto leave;
    }
    _gpgme_data_set_mode (plain, GPGME_DATA_MODE_OUT );
    if ( !ciph || gpgme_data_get_type (ciph) != GPGME_DATA_TYPE_NONE ) {
        rc = mk_error (Invalid_Value);
        goto leave;
    }
    _gpgme_data_set_mode (ciph, GPGME_DATA_MODE_IN );
    /* Tell the gpg object about the data */
    _gpgme_gpg_add_arg ( c->gpg, "--output" );
    _gpgme_gpg_add_arg ( c->gpg, "-" );
    _gpgme_gpg_add_data ( c->gpg, ciph, 1 );
    _gpgme_gpg_add_arg ( c->gpg, "--" );
    _gpgme_gpg_add_data ( c->gpg, plain, 0 );

    /* and kick off the process */
    rc = _gpgme_gpg_spawn ( c->gpg, c );

 leave:
    if (rc) {
        c->pending = 0; 
        _gpgme_gpg_release ( c->gpg ); c->gpg = NULL;
    }
    return rc;
}


/**
 * gpgme_op_encrypt:
 * @c: The context
 * @recp: A set of recipients 
 * @in: plaintext input
 * @out: ciphertext output
 * 
 * This function encrypts @in to @out for all recipients from
 * @recp.  Other parameters are take from the context @c.
 * The function does wait for the result.
 * 
 * Return value:  0 on success or an errorcode. 
 **/
GpgmeError
gpgme_op_encrypt ( GpgmeCtx c, GpgmeRecipients recp,
                   GpgmeData in, GpgmeData out )
{
    int err = gpgme_op_encrypt_start ( c, recp, in, out );
    if ( !err ) {
        gpgme_wait (c, 1);
        if (!c->result.encrypt)
            err = mk_error (General_Error);
        else if (c->out_of_core)
            err = mk_error (Out_Of_Core);
        else {
            if (c->result.encrypt->no_recipients) 
                err = mk_error (No_Recipients);
        }
        c->pending = 0;
        /* Old gpg versions don't return status info for invalid
         * recipients, so we simply check whether we got any output at
         * all and if not assume that we don't have valid recipients
         * */
        if (!err && gpgme_data_get_type (out) == GPGME_DATA_TYPE_NONE)
            err = mk_error (No_Recipients);
    }
    return err;
}