[fwd] / fattr.c

/* -*-c-*-
 *
 * $Id: fattr.c,v 1.3 2002/01/13 14:50:22 mdw Exp $
 *
 * Handling of file attributes
 *
 * (c) 1999 Straylight/Edgeware
 */

/*----- Licensing notice --------------------------------------------------* 
 *
 * This file is part of the `fw' port forwarder.
 *
 * `fw' 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.
 * 
 * `fw' 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 `fw'; if not, write to the Free Software Foundation,
 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

/*----- Revision history --------------------------------------------------* 
 *
 * $Log: fattr.c,v $
 * Revision 1.3  2002/01/13 14:50:22  mdw
 * Delimiter-setting function names change.
 *
 * Revision 1.2  1999/08/19 18:32:48  mdw
 * Improve lexical analysis.  In particular, `chmod' patterns don't have to
 * be quoted any more.
 *
 * Revision 1.1  1999/07/26 23:33:56  mdw
 * Support code for new design.
 *
 */

/*----- Header files ------------------------------------------------------*/

#include "config.h"

#include <ctype.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>

#include <pwd.h>
#include <grp.h>

#include "conf.h"
#include "fattr.h"
#include "scan.h"

/*----- Global variables --------------------------------------------------*/

fattr fattr_global;

/*----- Main code ---------------------------------------------------------*/

/* --- @fattr_init@ --- *
 *
 * Arguments:	@fattr *f@ = pointer to file attributes
 *
 * Returns:	---
 *
 * Use:		Initializes a set of file attributes to default values.
 */

void fattr_init(fattr *f)
{
  unsigned um = umask(0);
  umask(um);
  f->mode = 0666 & ~um;
  f->uid = -1;
  f->gid = -1;
}

/* --- @fattr_option@ --- *
 *
 * Arguments:	@scanner *sc@ = pointer to scanner to read
 *		@fattr *f@ = pointer to file attributes to set
 *
 * Returns:	Whether the option was claimed.
 *
 * Use:		Reads file attributes from a scanner.
 */

int fattr_option(scanner *sc, fattr *f)
{
  CONF_BEGIN(sc, "fattr", "file attribute")

  /* --- Read a file mode specification --- */

  if (strcmp(sc->d.buf, "mode") == 0) {
    unsigned mode = 0;

    /* --- Gobble an optional `=' sign --- */

    conf_undelim(sc, 0, ",=+-");
    token(sc);
    if (sc->t == '=')
      token(sc);

    if (sc->t != CTOK_WORD)
      error(sc, "parse error, expected file mode");
    conf_undelim(sc, 0, 0);

    /* --- If it looks digitlike, read as octal --- */

    if (isdigit((unsigned char)*sc->d.buf))
      mode = strtoul(sc->d.buf, 0, 8) & 07777;

    /* --- Otherise read as chmod-like characters --- */

    else {
      const char *p;
      unsigned mask = 04700;
      unsigned state = 0;
      unsigned or = 1;

      /* --- Set the default from the umask --- */

      {
	unsigned um = umask(0);
	umask(um);
	mode = 0666 & ~um;
      }

      /* --- Parse the characters --- *
       *
       * This is a particularly lenient implementation of the usual chmod-
       * style mode language.
       */

      for (p = sc->d.buf; *p; p++) {
	switch (*p) {
	  case ',': break;

	  case 'a': mask = (mask & state) | 07777; state = 07777; break;
	  case 'u': mask = (mask & state) | 04700; state = 07777; break;
	  case 'g': mask = (mask & state) | 02070; state = 07777; break;
	  case 'o': mask = (mask & state) | 01007; state = 07777; break;

	  case '=': mode &= ~mask; /* Drop through */
	  case '+': state = 0; or = 1; break;
	  case '-': state = 0; or = 0; break;

#define APPLY(m) if (or) mode |= ((m) & mask); else mode &= ~((m) & mask);
	  case 'r': state = 0; APPLY(00444); break;
	  case 'w': state = 0; APPLY(00222); break;
	  case 'x': state = 0; APPLY(00111); break;
	  case 's': state = 0; APPLY(06000); break;
	  case 't': state = 0; APPLY(01000); break;
#undef APPLY

	  default: error(sc, "unknown mode character `%c'", *p);
	}
      }
    }

    token(sc);
    f->mode = mode;
    CONF_ACCEPT;
  }

  /* --- Read a file uid specification --- */

  if (strcmp(sc->d.buf, "uid") == 0 ||
      strcmp(sc->d.buf, "user") == 0 ||
      strcmp(sc->d.buf, "owner") == 0) {
    token(sc);
    if (sc->t == '=')
      token(sc);
    if (sc->t != CTOK_WORD)
      error(sc, "parse error, expected user name or uid");
    if (isdigit((unsigned char)*sc->d.buf))
      f->uid = atoi(sc->d.buf);
    else {
      struct passwd *pw = getpwnam(sc->d.buf);
      if (!pw)
	error(sc, "unknown user name `%s'", sc->d.buf);
      f->uid = pw->pw_uid;
    }
    token(sc);
    CONF_ACCEPT;
  }

  /* --- Read a file gid specification --- */

  if (strcmp(sc->d.buf, "gid") == 0 ||
      strcmp(sc->d.buf, "group") == 0) {
    token(sc);
    if (sc->t == '=')
      token(sc);
    if (sc->t != CTOK_WORD)
      error(sc, "parse error, expected group name or gid");
    if (isdigit((unsigned char)*sc->d.buf))
      f->gid = atoi(sc->d.buf);
    else {
      struct group *gr = getgrnam(sc->d.buf);
      if (!gr)
	error(sc, "unknown user name `%s'", sc->d.buf);
      f->gid = gr->gr_gid;
    }
    token(sc);
    CONF_ACCEPT;
  }

  /* --- Nothing here for me --- */

  CONF_END;
}

/* --- @fattr_apply@ --- *
 *
 * Arguments:	@const char *file@ = pointer to filename
 *		@fattr *f@ = pointer to attribute set
 *
 * Returns:	@-1@ if it failed.
 *
 * Use:		Applies file attributes to a file.  For best results, try to
 *		create the file with the right permissions and so on.  This
 *		call will fix everything up, but there are potential races
 *		which might catch you out if you're not careful.
 */

int fattr_apply(const char *file, fattr *f)
{
  if (chown(file, f->uid, f->gid) == -1 ||
      chmod(file, f->mode) == -1)
    return (-1);
  return (0);
}

/*----- That's all, folks -------------------------------------------------*/
Commit	Line	Data
3b7defab	1	/* --c--
3b7defab	2	*
9b699b28	3	* $Id: fattr.c,v 1.3 2002/01/13 14:50:22 mdw Exp $
3b7defab	4	*
	5	* Handling of file attributes
	6	*
	7	* (c) 1999 Straylight/Edgeware
	8	*/
	9
	10	/----- Licensing notice --------------------------------------------------
	11	*
	12	* This file is part of the `fw' port forwarder.
	13	*
	14	* `fw' is free software; you can redistribute it and/or modify
	15	* it under the terms of the GNU General Public License as published by
	16	* the Free Software Foundation; either version 2 of the License, or
	17	* (at your option) any later version.
	18	*
	19	* `fw' is distributed in the hope that it will be useful,
	20	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	21	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	22	* GNU General Public License for more details.
	23	*
	24	* You should have received a copy of the GNU General Public License
	25	* along with `fw'; if not, write to the Free Software Foundation,
	26	* Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
	27	*/
	28
	29	/----- Revision history --------------------------------------------------
	30	*
	31	* $Log: fattr.c,v $
9b699b28	32	* Revision 1.3 2002/01/13 14:50:22 mdw
	33	* Delimiter-setting function names change.
	34	*
e73034b0	35	* Revision 1.2 1999/08/19 18:32:48 mdw
	36	* Improve lexical analysis. In particular, `chmod' patterns don't have to
	37	* be quoted any more.
	38	*
3b7defab	39	* Revision 1.1 1999/07/26 23:33:56 mdw
	40	* Support code for new design.
	41	*
	42	*/
	43
	44	/----- Header files ------------------------------------------------------/
	45
	46	#include "config.h"
	47
	48	#include <ctype.h>
	49	#include <errno.h>
	50	#include <stdio.h>
	51	#include <stdlib.h>
	52	#include <string.h>
	53
	54	#include <sys/types.h>
	55	#include <sys/stat.h>
	56	#include <unistd.h>
	57
	58	#include <pwd.h>
	59	#include <grp.h>
	60
	61	#include "conf.h"
	62	#include "fattr.h"
	63	#include "scan.h"
	64
	65	/----- Global variables --------------------------------------------------/
	66
	67	fattr fattr_global;
	68
	69	/----- Main code ---------------------------------------------------------/
	70
	71	/* --- @fattr_init@ --- *
	72	*
	73	* Arguments: @fattr *f@ = pointer to file attributes
	74	*
	75	* Returns: ---
	76	*
	77	* Use: Initializes a set of file attributes to default values.
	78	*/
	79
	80	void fattr_init(fattr *f)
	81	{
	82	unsigned um = umask(0);
	83	umask(um);
	84	f->mode = 0666 & ~um;
	85	f->uid = -1;
	86	f->gid = -1;
	87	}
	88
	89	/* --- @fattr_option@ --- *
	90	*
	91	* Arguments: @scanner *sc@ = pointer to scanner to read
	92	* @fattr *f@ = pointer to file attributes to set
	93	*
	94	* Returns: Whether the option was claimed.
	95	*
	96	* Use: Reads file attributes from a scanner.
	97	*/
	98
	99	int fattr_option(scanner sc, fattr f)
	100	{
	101	CONF_BEGIN(sc, "fattr", "file attribute")
	102
103	/* --- Read a file mode specification --- */
104
105	if (strcmp(sc->d.buf, "mode") == 0) {
106	unsigned mode = 0;
107
108	/* --- Gobble an optional `=' sign --- */
109
9b699b28	110	conf_undelim(sc, 0, ",=+-");
3b7defab	111	token(sc);
	112	if (sc->t == '=')
	113	token(sc);
	114
	115	if (sc->t != CTOK_WORD)
	116	error(sc, "parse error, expected file mode");
9b699b28	117	conf_undelim(sc, 0, 0);
3b7defab	118
	119	/* --- If it looks digitlike, read as octal --- */
	120
	121	if (isdigit((unsigned char)*sc->d.buf))
	122	mode = strtoul(sc->d.buf, 0, 8) & 07777;
	123
	124	/* --- Otherise read as chmod-like characters --- */
	125
	126	else {
	127	const char *p;
e73034b0	128	unsigned mask = 04700;
e73034b0	129	unsigned state = 0;
3b7defab	130	unsigned or = 1;
	131
	132	/* --- Set the default from the umask --- */
	133
	134	{
	135	unsigned um = umask(0);
	136	umask(um);
	137	mode = 0666 & ~um;
	138	}
	139
	140	/* --- Parse the characters --- *
	141	*
	142	* This is a particularly lenient implementation of the usual chmod-
	143	* style mode language.
	144	*/
	145
	146	for (p = sc->d.buf; *p; p++) {
	147	switch (*p) {
	148	case ',': break;
	149
e73034b0	150	case 'a': mask = (mask & state) \| 07777; state = 07777; break;
	151	case 'u': mask = (mask & state) \| 04700; state = 07777; break;
	152	case 'g': mask = (mask & state) \| 02070; state = 07777; break;
	153	case 'o': mask = (mask & state) \| 01007; state = 07777; break;
3b7defab	154
e73034b0	155	case '=': mode &= ~mask; /* Drop through */
	156	case '+': state = 0; or = 1; break;
	157	case '-': state = 0; or = 0; break;
3b7defab	158
3b7defab	159	#define APPLY(m) if (or) mode \|= ((m) & mask); else mode &= ~((m) & mask);
e73034b0	160	case 'r': state = 0; APPLY(00444); break;
	161	case 'w': state = 0; APPLY(00222); break;
	162	case 'x': state = 0; APPLY(00111); break;
	163	case 's': state = 0; APPLY(06000); break;
	164	case 't': state = 0; APPLY(01000); break;
3b7defab	165	#undef APPLY
	166
	167	default: error(sc, "unknown mode character `%c'", *p);
	168	}
	169	}
	170	}
	171
	172	token(sc);
	173	f->mode = mode;
	174	CONF_ACCEPT;
	175	}
	176
	177	/* --- Read a file uid specification --- */
	178
	179	if (strcmp(sc->d.buf, "uid") == 0 \|\|
	180	strcmp(sc->d.buf, "user") == 0 \|\|
	181	strcmp(sc->d.buf, "owner") == 0) {
	182	token(sc);
	183	if (sc->t == '=')
	184	token(sc);
	185	if (sc->t != CTOK_WORD)
	186	error(sc, "parse error, expected user name or uid");
	187	if (isdigit((unsigned char)*sc->d.buf))
	188	f->uid = atoi(sc->d.buf);
	189	else {
	190	struct passwd *pw = getpwnam(sc->d.buf);
	191	if (!pw)
	192	error(sc, "unknown user name `%s'", sc->d.buf);
	193	f->uid = pw->pw_uid;
	194	}
	195	token(sc);
	196	CONF_ACCEPT;
	197	}
	198
	199	/* --- Read a file gid specification --- */
	200
	201	if (strcmp(sc->d.buf, "gid") == 0 \|\|
	202	strcmp(sc->d.buf, "group") == 0) {
	203	token(sc);
	204	if (sc->t == '=')
	205	token(sc);
	206	if (sc->t != CTOK_WORD)
	207	error(sc, "parse error, expected group name or gid");
	208	if (isdigit((unsigned char)*sc->d.buf))
	209	f->gid = atoi(sc->d.buf);
	210	else {
	211	struct group *gr = getgrnam(sc->d.buf);
	212	if (!gr)
	213	error(sc, "unknown user name `%s'", sc->d.buf);
	214	f->gid = gr->gr_gid;
	215	}
	216	token(sc);
	217	CONF_ACCEPT;
	218	}
	219
	220	/* --- Nothing here for me --- */
	221
	222	CONF_END;
	223	}
	224
	225	/* --- @fattr_apply@ --- *
	226	*
	227	* Arguments: @const char *file@ = pointer to filename
	228	* @fattr *f@ = pointer to attribute set
229	*
230	* Returns: @-1@ if it failed.
231	*
232	* Use: Applies file attributes to a file. For best results, try to
233	* create the file with the right permissions and so on. This
234	* call will fix everything up, but there are potential races
235	* which might catch you out if you're not careful.
236	*/
237
238	int fattr_apply(const char file, fattr f)
239	{
240	if (chown(file, f->uid, f->gid) == -1 \|\|
241	chmod(file, f->mode) == -1)
242	return (-1);
243	return (0);
244	}
245
246	/----- That's all, folks -------------------------------------------------/