pgp.c

mutt-1.5.12 源代码。linux 下邮件接受的工具。

    return 0;

  /* fix the content type */
  
  mutt_set_parameter ("format", "fixed", &b->parameter);
  if (enc)
    mutt_set_parameter ("x-action", "pgp-encrypted", &b->parameter);
  else if (sgn)
    mutt_set_parameter ("x-action", "pgp-signed", &b->parameter);
  else if (key)
    mutt_set_parameter ("x-action", "pgp-keys", &b->parameter);
  
  return 1;
}

int pgp_check_traditional (FILE *fp, BODY *b, int tagged_only)
{
  int rv = 0;
  int r;
  for (; b; b = b->next)
  {
    if (is_multipart (b))
      rv = pgp_check_traditional (fp, b->parts, tagged_only) || rv;
    else if (b->type == TYPETEXT)
    {
      if ((r = mutt_is_application_pgp (b)))
	rv = rv || r;
      else
	rv = pgp_check_traditional_one_body (fp, b, tagged_only) || rv;
    }
  }

  return rv;
}

     



int pgp_verify_one (BODY *sigbdy, STATE *s, const char *tempfile)
{
  char sigfile[_POSIX_PATH_MAX], pgperrfile[_POSIX_PATH_MAX];
  FILE *fp, *pgpout, *pgperr;
  pid_t thepid;
  int badsig = -1;
  int rv;
  
  snprintf (sigfile, sizeof (sigfile), "%s.asc", tempfile);
  
  if(!(fp = safe_fopen (sigfile, "w")))
  {
    mutt_perror(sigfile);
    return -1;
  }
	
  fseeko (s->fpin, sigbdy->offset, 0);
  mutt_copy_bytes (s->fpin, fp, sigbdy->length);
  fclose (fp);
  
  mutt_mktemp(pgperrfile);
  if(!(pgperr = safe_fopen(pgperrfile, "w+")))
  {
    mutt_perror(pgperrfile);
    unlink(sigfile);
    return -1;
  }
  
  crypt_current_time (s, "PGP");
  
  if((thepid = pgp_invoke_verify (NULL, &pgpout, NULL, 
				   -1, -1, fileno(pgperr),
				   tempfile, sigfile)) != -1)
  {
    if (pgp_copy_checksig (pgpout, s->fpout) >= 0)
      badsig = 0;
    
    
    safe_fclose (&pgpout);
    fflush (pgperr);
    rewind (pgperr);
    
    if (pgp_copy_checksig  (pgperr, s->fpout) >= 0)
      badsig = 0;

    if ((rv = mutt_wait_filter (thepid)))
      badsig = -1;
    
     dprint (1, (debugfile, "pgp_verify_one: mutt_wait_filter returned %d.\n", rv));
  }

  safe_fclose (&pgperr);

  state_attach_puts (_("[-- End of PGP output --]\n\n"), s);

  mutt_unlink (sigfile);
  mutt_unlink (pgperrfile);

  dprint (1, (debugfile, "pgp_verify_one: returning %d.\n", badsig));
  
  return badsig;
}


/* Extract pgp public keys from messages or attachments */

void pgp_extract_keys_from_messages (HEADER *h)
{
  int i;
  char tempfname[_POSIX_PATH_MAX];
  FILE *fpout;

  if (h)
  {
    mutt_parse_mime_message (Context, h);
    if(h->security & PGPENCRYPT && !pgp_valid_passphrase ())
      return;
  }

  mutt_mktemp (tempfname);
  if (!(fpout = safe_fopen (tempfname, "w")))
  {
    mutt_perror (tempfname);
    return;
  }

  set_option (OPTDONTHANDLEPGPKEYS);
  
  if (!h)
  {
    for (i = 0; i < Context->vcount; i++)
    {
      if (Context->hdrs[Context->v2r[i]]->tagged)
      {
	mutt_parse_mime_message (Context, Context->hdrs[Context->v2r[i]]);
	if (Context->hdrs[Context->v2r[i]]->security & PGPENCRYPT
	   && !pgp_valid_passphrase())
	{
	  fclose (fpout);
	  goto bailout;
	}
	mutt_copy_message (fpout, Context, Context->hdrs[Context->v2r[i]], 
			   M_CM_DECODE|M_CM_CHARCONV, 0);
      }
    }
  } 
  else
  {
    mutt_parse_mime_message (Context, h);
    if (h->security & PGPENCRYPT && !pgp_valid_passphrase())
    {
      fclose (fpout);
      goto bailout;
    }
    mutt_copy_message (fpout, Context, h, M_CM_DECODE|M_CM_CHARCONV, 0);
  }
      
  fclose (fpout);
  mutt_endwin (NULL);
  pgp_invoke_import (tempfname);
  mutt_any_key_to_continue (NULL);

  bailout:
  
  mutt_unlink (tempfname);
  unset_option (OPTDONTHANDLEPGPKEYS);
  
}

static void pgp_extract_keys_from_attachment (FILE *fp, BODY *top)
{
  STATE s;
  FILE *tempfp;
  char tempfname[_POSIX_PATH_MAX];

  mutt_mktemp (tempfname);
  if (!(tempfp = safe_fopen (tempfname, "w")))
  {
    mutt_perror (tempfname);
    return;
  }

  memset (&s, 0, sizeof (STATE));
  
  s.fpin = fp;
  s.fpout = tempfp;
  
  mutt_body_handler (top, &s);

  fclose (tempfp);

  pgp_invoke_import (tempfname);
  mutt_any_key_to_continue (NULL);

  mutt_unlink (tempfname);
}

void pgp_extract_keys_from_attachment_list (FILE *fp, int tag, BODY *top)
{
  if(!fp)
  {
    mutt_error _("Internal error. Inform <[e-mail]>.");
    return;
  }

  mutt_endwin (NULL);
  set_option(OPTDONTHANDLEPGPKEYS);
  
  for(; top; top = top->next)
  {
    if(!tag || top->tagged)
      pgp_extract_keys_from_attachment (fp, top);
    
    if(!tag)
      break;
  }
  
  unset_option(OPTDONTHANDLEPGPKEYS);
}

BODY *pgp_decrypt_part (BODY *a, STATE *s, FILE *fpout, BODY *p)
{
  char buf[LONG_STRING];
  FILE *pgpin, *pgpout, *pgperr, *pgptmp;
  struct stat info;
  BODY *tattach;
  int len;
  char pgperrfile[_POSIX_PATH_MAX];
  char pgptmpfile[_POSIX_PATH_MAX];
  pid_t thepid;
  int rv;
  
  mutt_mktemp (pgperrfile);
  if ((pgperr = safe_fopen (pgperrfile, "w+")) == NULL)
  {
    mutt_perror (pgperrfile);
    return NULL;
  }
  unlink (pgperrfile);

  mutt_mktemp (pgptmpfile);
  if((pgptmp = safe_fopen (pgptmpfile, "w")) == NULL)
  {
    mutt_perror (pgptmpfile);
    fclose(pgperr);
    return NULL;
  }

  /* Position the stream at the beginning of the body, and send the data to
   * the temporary file.
   */

  fseeko (s->fpin, a->offset, 0);
  mutt_copy_bytes (s->fpin, pgptmp, a->length);
  fclose (pgptmp);

  if ((thepid = pgp_invoke_decrypt (&pgpin, &pgpout, NULL, -1, -1,
				    fileno (pgperr), pgptmpfile)) == -1)
  {
    fclose (pgperr);
    unlink (pgptmpfile);
    if (s->flags & M_DISPLAY)
      state_attach_puts (_("[-- Error: could not create a PGP subprocess! --]\n\n"), s);
    return (NULL);
  }

  /* send the PGP passphrase to the subprocess.  Never do this if the
     agent is active, because this might lead to a passphrase send as
     the message. */
  if (!pgp_use_gpg_agent())
    fputs (PgpPass, pgpin);
  fputc ('\n', pgpin);
  fclose(pgpin);
  
  /* Read the output from PGP, and make sure to change CRLF to LF, otherwise
   * read_mime_header has a hard time parsing the message.
   */
  while (fgets (buf, sizeof (buf) - 1, pgpout) != NULL)
  {
    len = mutt_strlen (buf);
    if (len > 1 && buf[len - 2] == '\r')
      strcpy (buf + len - 2, "\n");	/* __STRCPY_CHECKED__ */
    fputs (buf, fpout);
  }

  fclose (pgpout);
  rv = mutt_wait_filter (thepid);
  mutt_unlink(pgptmpfile);
  
  if (s->flags & M_DISPLAY)
  {
    fflush (pgperr);
    rewind (pgperr);
    if (pgp_copy_checksig (pgperr, s->fpout) == 0 && !rv && p)
      p->goodsig = 1;
    else
      p->goodsig = 0;
    state_attach_puts (_("[-- End of PGP output --]\n\n"), s);
  }
  fclose (pgperr);

  fflush (fpout);
  rewind (fpout);
  
  if (fgetc (fpout) == EOF)
  {
    mutt_error _("Decryption failed");
    pgp_void_passphrase ();
    return NULL;
  }

  rewind (fpout);
  
  if ((tattach = mutt_read_mime_header (fpout, 0)) != NULL)
  {
    /*
     * Need to set the length of this body part.
     */
    fstat (fileno (fpout), &info);
    tattach->length = info.st_size - tattach->offset;

    /* See if we need to recurse on this MIME part.  */

    mutt_parse_part (fpout, tattach);
  }

  return (tattach);
}

int pgp_decrypt_mime (FILE *fpin, FILE **fpout, BODY *b, BODY **cur)
{
  char tempfile[_POSIX_PATH_MAX];
  STATE s;
  BODY *p = b;
  
  if(!mutt_is_multipart_encrypted(b))
    return -1;

  if(!b->parts || !b->parts->next)
    return -1;
  
  b = b->parts->next;
  
  memset (&s, 0, sizeof (s));
  s.fpin = fpin;
  mutt_mktemp (tempfile);
  if ((*fpout = safe_fopen (tempfile, "w+")) == NULL)
  {
    mutt_perror (tempfile);
    return (-1);
  }
  unlink (tempfile);

  *cur = pgp_decrypt_part (b, &s, *fpout, p);

  rewind (*fpout);
  
  if (!*cur)
    return -1;
  
  return (0);
}

int pgp_encrypted_handler (BODY *a, STATE *s)
{
  char tempfile[_POSIX_PATH_MAX];
  FILE *fpout, *fpin;
  BODY *tattach;
  BODY *p = a;
  int rc = 0;
  
  a = a->parts;
  if (!a || a->type != TYPEAPPLICATION || !a->subtype || 
      ascii_strcasecmp ("pgp-encrypted", a->subtype) != 0 ||
      !a->next || a->next->type != TYPEAPPLICATION || !a->next->subtype ||
      ascii_strcasecmp ("octet-stream", a->next->subtype) != 0)
  {
    if (s->flags & M_DISPLAY)
      state_attach_puts (_("[-- Error: malformed PGP/MIME message! --]\n\n"), s);
    return -1;
  }

  /*
   * Move forward to the application/pgp-encrypted body.
   */
  a = a->next;

  mutt_mktemp (tempfile);
  if ((fpout = safe_fopen (tempfile, "w+")) == NULL)
  {
    if (s->flags & M_DISPLAY)
      state_attach_puts (_("[-- Error: could not create temporary file! --]\n"), s);
    return -1;
  }

  if (s->flags & M_DISPLAY) crypt_current_time (s, "PGP");

  if ((tattach = pgp_decrypt_part (a, s, fpout, p)) != NULL)
  {
    if (s->flags & M_DISPLAY)
      state_attach_puts (_("[-- The following data is PGP/MIME encrypted --]\n\n"), s);

    fpin = s->fpin;
    s->fpin = fpout;
    rc = mutt_body_handler (tattach, s);
    s->fpin = fpin;

    /* 
     * if a multipart/signed is the _only_ sub-part of a
     * multipart/encrypted, cache signature verification
     * status.
     *
     */
    
    if (mutt_is_multipart_signed (tattach) && !tattach->next)
      p->goodsig |= tattach->goodsig;
    
    if (s->flags & M_DISPLAY)
    {
      state_puts ("\n", s);
      state_attach_puts (_("[-- End of PGP/MIME encrypted data --]\n"), s);
    }

    mutt_free_body (&tattach);
    /* clear 'Invoking...' message, since there's no error */
    mutt_message _("PGP message successfully decrypted.");
  }
  else
  {
    mutt_error _("Could not decrypt PGP message");
    /* void the passphrase, even if it's not necessarily the problem */
    pgp_void_passphrase ();
    rc = -1;
  }

  fclose (fpout);
  mutt_unlink(tempfile);

  return rc;
}

/* ----------------------------------------------------------------------------
 * Routines for sending PGP/MIME messages.
 */


BODY *pgp_sign_message (BODY *a)
{
  BODY *t;
  char buffer[LONG_STRING];
  char sigfile[_POSIX_PATH_MAX], signedfile[_POSIX_PATH_MAX];
  FILE *pgpin, *pgpout, *pgperr, *fp, *sfp;
  int err = 0;
  int empty = 1;
  pid_t thepid;
  
  convert_to_7bit (a); /* Signed data _must_ be in 7-bit format. */

  mutt_mktemp (sigfile);
  if ((fp = safe_fopen (sigfile, "w")) == NULL)
  {
    return (NULL);
  }

  mutt_mktemp (signedfile);
  if ((sfp = safe_fopen(signedfile, "w")) == NULL)
  {
    mutt_perror(signedfile);
    fclose(fp);
    unlink(sigfile);
    return NULL;
  }
  
  mutt_write_mime_header (a, sfp);
  fputc ('\n', sfp);
  mutt_write_mime_body (a, sfp);
  fclose(sfp);
  
  if ((thepid = pgp_invoke_sign (&pgpin, &pgpout, &pgperr,
				 -1, -1, -1, signedfile)) == -1)
  {
    mutt_perror _("Can't open PGP subprocess!");
    fclose(fp);
    unlink(sigfile);
    unlink(signedfile);
    return NULL;
  }
  
  if (!pgp_use_gpg_agent())
     fputs(PgpPass, pgpin);
  fputc('\n', pgpin);
  fclose(pgpin);
  
  /*
   * Read back the PGP signature.  Also, change MESSAGE=>SIGNATURE as
   * recommended for future releases of PGP.
   */
  while (fgets (buffer, sizeof (buffer) - 1, pgpout) != NULL)
  {
    if (mutt_strcmp ("-----BEGIN PGP MESSAGE-----\n", buffer) == 0)
      fputs ("-----BEGIN PGP SIGNATURE-----\n", fp);
    else if (mutt_strcmp("-----END PGP MESSAGE-----\n", buffer) == 0)
      fputs ("-----END PGP SIGNATURE-----\n", fp);
    else
      fputs (buffer, fp);
    empty = 0; /* got some output, so we're ok */
  }

  /* check for errors from PGP */
  err = 0;
  while (fgets (buffer, sizeof (buffer) - 1, pgperr) != NULL)
  {
    err = 1;
    fputs (buffer, stdout);
  }

  if(mutt_wait_filter (thepid) && option(OPTPGPCHECKEXIT))
    empty=1;

  fclose (pgperr);
  fclose (pgpout);
  unlink (signedfile);
  
  if (fclose (fp) != 0)
  {
    mutt_perror ("fclose");
    unlink (sigfile);
    return (NULL);
  }

  if (err)
    mutt_any_key_to_continue (NULL);
  if (empty)
  {
    unlink (sigfile);
    /* most likely error is a bad passphrase, so automatically forget it */
    pgp_void_passphrase ();
    return (NULL); /* fatal error while signing */
  }

  t = mutt_new_body ();
  t->type = TYPEMULTIPART;
  t->subtype = safe_strdup ("signed");
  t->encoding = ENC7BIT;
  t->use_disp = 0;