gpgme/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 ctx, GpgmeRecipients recp, GpgmeData plain,
			GpgmeData ciph)
{
  int err = 0;

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

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

  /* Do some checks.  */
  if (!gpgme_recipients_count (recp))
    {
      /* Fixme: In this case we should do symmentric encryption.  */
      err = mk_error (No_Recipients);
      goto leave;
    }

  /* Create an engine object.  */
  _gpgme_engine_release (ctx->engine);
  ctx->engine = NULL;
  err = _gpgme_engine_new (ctx->use_cms ? GPGME_PROTOCOL_CMS
			   : GPGME_PROTOCOL_OpenPGP, &ctx->engine);
  if (err)
    goto leave;

  _gpgme_engine_set_status_handler (ctx->engine, encrypt_status_handler, ctx);
  _gpgme_engine_set_verbosity (ctx->engine, ctx->verbosity);

  /* Check the supplied data */
  if (gpgme_data_get_type (plain) == GPGME_DATA_TYPE_NONE)
    {
      err = 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)
    {
      err = mk_error (Invalid_Value);
      goto leave;
    }
  _gpgme_data_set_mode (ciph, GPGME_DATA_MODE_IN);

  err = _gpgme_engine_op_encrypt (ctx->engine, recp, plain, ciph, ctx->use_armor);


  if (!err)	/* And kick off the process.  */
    err = _gpgme_engine_start (ctx->engine, ctx);

 leave:
  if (err)
    {
      ctx->pending = 0; 
      _gpgme_engine_release (ctx->engine);
      ctx->engine = NULL;
    }
  return err;
}


/**
 * 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;
}