gnupg/sm/import.c

/* import.c - Import certificates
 *	Copyright (C) 2001 Free Software Foundation, Inc.
 *
 * This file is part of GnuPG.
 *
 * GnuPG 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.
 *
 * GnuPG 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 <errno.h>
#include <unistd.h> 
#include <time.h>
#include <assert.h>

#include <gcrypt.h>
#include <ksba.h>

#include "gpgsm.h"
#include "keydb.h"
#include "i18n.h"

struct reader_cb_parm_s {
  FILE *fp;
  unsigned char line[1024];
  int linelen;
  int readpos;
  int have_lf;
  unsigned long line_counter;

  int identified;
  int is_pem;
  int stop_seen;

  struct {
    int idx;
    unsigned char val;
    int stop_seen;
  } base64;


};

/*  static unsigned char bintoasc[] =  */
/*  "ABCDEFGHIJKLMNOPQRSTUVWXYZ" */
/*  "abcdefghijklmnopqrstuvwxyz" */
/*  "0123456789+/"; */

static unsigned char asctobin[256] = {
  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x3e, 0xff, 0xff, 0xff, 0x3f, 
  0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0xff, 0xff, 
  0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 
  0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, 
  0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0xff, 0xff, 0xff, 0xff, 0xff, 
  0xff, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, 0x21, 0x22, 0x23, 0x24, 
  0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, 0x30, 
  0x31, 0x32, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
  0xff, 0xff, 0xff, 0xff
};



static int
reader_cb (void *cb_value, char *buffer, size_t count, size_t *nread)
{
  struct reader_cb_parm_s *parm = cb_value;
  size_t n;
  int c, c2;

  *nread = 0;
  if (!buffer)
    return -1; /* not supported */

 next:
  if (!parm->linelen)
    {
      /* read an entire line or up to the size of the buffer */
      parm->line_counter++;
      parm->have_lf = 0;
      for (n=0; n < DIM(parm->line);)
        {
          c = getc (parm->fp);
          if (c == EOF)
            {
              if (ferror (parm->fp))
                return -1;
              break; 
            }
          parm->line[n++] = c;
          if (c == '\n')
            {
              parm->have_lf = 1;
              /* FIXME: we need to skip overlong lines while detecting
                 the dashed lines */
              break;
            }
        }
      parm->linelen = n;
      if (!n)
        return -1; /* eof */
      parm->readpos = 0;
    }

  if (!parm->identified)
    {
      if (parm->line_counter == 1 && !parm->have_lf)
        {
          /* first line too long - assume DER encoding */
          parm->is_pem = 0;
        }
      else if (parm->line_counter == 1 && parm->linelen && *parm->line == 0x30)
        {
          /* the very first bytes does pretty much look like a SEQUENCE tag*/
          parm->is_pem = 0;
        }
      else if ( parm->have_lf && !strncmp (parm->line, "-----BEGIN ", 11)
                && strncmp (parm->line+11, "PGP ", 4) )
        {
          /* Fixme: we must only compare if the line really starts at
             the beginning */
          parm->is_pem = 1;
          parm->linelen = parm->readpos = 0;
        }
      else
        {
          parm->linelen = parm->readpos = 0;
          goto next;
        }
      parm->identified = 1;
      parm->base64.stop_seen = 0;
      parm->base64.idx = 0;
    }
  

  n = 0;
  if (parm->is_pem)
    {  
      if (parm->have_lf && !strncmp (parm->line, "-----END ", 9))
        { 
          parm->identified = 0;
          parm->linelen = parm->readpos = 0;
          /* let us return 0 */
        }
      else if (parm->stop_seen)
        { /* skip the rest of the line */
          parm->linelen = parm->readpos = 0;
        }
      else
        {
          int idx = parm->base64.idx;
          unsigned char val = parm->base64.val;

          while (n < count && parm->readpos < parm->linelen )
            {
              c = parm->line[parm->readpos++];
              if (c == '\n' || c == ' ' || c == '\r' || c == '\t')
                continue;
              if (c == '=')
                { /* pad character: stop */
                  if (idx == 1)
                    buffer[n++] = val; 
                  parm->stop_seen = 1;
                  break;
                }
              if( (c = asctobin[(c2=c)]) == 255 ) 
                {
                  log_error (_("invalid radix64 character %02x skipped\n"),
                             c2);
                  continue;
                }
              switch (idx) 
                {
                case 0: 
                  val = c << 2;
                  break;
                case 1: 
                  val |= (c>>4)&3;
                  buffer[n++] = val;
                  val = (c<<4)&0xf0;
                  break;
                case 2: 
                  val |= (c>>2)&15;
                  buffer[n++] = val;
                  val = (c<<6)&0xc0;
                  break;
                case 3: 
                  val |= c&0x3f;
                  buffer[n++] = val;
                  break;
                }
              idx = (idx+1) % 4;
            }
          if (parm->readpos == parm->linelen)
            parm->linelen = parm->readpos = 0;

          parm->base64.idx = idx;
          parm->base64.val = val;
        }
    }
  else
    { /* DER encoded */
      while (n < count && parm->readpos < parm->linelen)
          buffer[n++] = parm->line[parm->readpos++];
      if (parm->readpos == parm->linelen)
        parm->linelen = parm->readpos = 0;
    }

  *nread = n;
  return 0;
}


static void
store_cert (KsbaCert cert)
{
  KEYDB_HANDLE kh;
  int rc;

  kh = keydb_new (0);
  if (!kh)
    {
      log_error (_("failed to allocated keyDB handle\n"));
      return;
    }
  rc = keydb_locate_writable (kh, 0);
  if (rc)
      log_error (_("error finding writable keyDB: %s\n"), gnupg_strerror (rc));

  rc = keydb_insert_cert (kh, cert);
  if (rc)
    {
      log_error (_("error storing certificate: %s\n"), gnupg_strerror (rc));
    }
  keydb_release (kh);               
}




int
gpgsm_import (CTRL ctrl, int in_fd)
{
  int rc;
  KsbaReader reader = NULL;
  KsbaCert cert = NULL;
  struct reader_cb_parm_s rparm;

  memset (&rparm, 0, sizeof rparm);

  rparm.fp = fdopen ( dup (in_fd), "rb");
  if (!rparm.fp)
    {
      log_error ("fdopen() failed: %s\n", strerror (errno));
      rc = seterr (IO_Error);
      goto leave;
    }

  /* setup a skaba reader which uses a callback function so that we can 
     strip off a base64 encoding when necessary */
  reader = ksba_reader_new ();
  if (!reader)
    {
      rc = seterr (Out_Of_Core);
      goto leave;
    }

  rc = ksba_reader_set_cb (reader, reader_cb, &rparm );
  if (rc)
    {
      ksba_reader_release (reader);
      rc = map_ksba_err (rc);
      goto leave;
    }

  cert = ksba_cert_new ();
  if (!cert)
    {
      rc = seterr (Out_Of_Core);
      goto leave;
    }

  rc = ksba_cert_read_der (cert, reader);
  if (rc)
    {
      rc = map_ksba_err (rc);
      goto leave;
    }

  if ( !gpgsm_validate_path (cert) )
    store_cert (cert);

 leave:
  ksba_cert_release (cert);
  ksba_reader_release (reader);
  if (rparm.fp)
    fclose (rparm.fp);
  return rc;
}