/* modechange.c -- file mode manipulation
- Copyright (C) 1989, 1990, 1997 Free Software Foundation, Inc.
+
+ Copyright (C) 1989, 1990, 1997, 1998, 1999, 2001, 2003, 2004 Free
+ Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
# include <config.h>
#endif
-#include <sys/types.h>
-#include <sys/stat.h>
#include "modechange.h"
-
-#if STDC_HEADERS
-# include <stdlib.h>
-#else
-char *malloc ();
-#endif
-
-#ifndef NULL
-# define NULL 0
-#endif
+#include <sys/stat.h>
+#include "xstrtol.h"
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdlib.h>
#if STAT_MACROS_BROKEN
# undef S_ISDIR
# define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
#endif
+/* The traditional octal values corresponding to each mode bit. */
+#define SUID 04000
+#define SGID 02000
+#define SVTX 01000
+#define RUSR 00400
+#define WUSR 00200
+#define XUSR 00100
+#define RGRP 00040
+#define WGRP 00020
+#define XGRP 00010
+#define ROTH 00004
+#define WOTH 00002
+#define XOTH 00001
+#define ALLM 07777 /* all octal mode bits */
+
+#ifndef S_ISUID
+# define S_ISUID SUID
+#endif
+#ifndef S_ISGID
+# define S_ISGID SGID
+#endif
+#ifndef S_ISVTX
+# define S_ISVTX SVTX
+#endif
+#ifndef S_IRUSR
+# define S_IRUSR RUSR
+#endif
+#ifndef S_IWUSR
+# define S_IWUSR WUSR
+#endif
+#ifndef S_IXUSR
+# define S_IXUSR XUSR
+#endif
+#ifndef S_IRGRP
+# define S_IRGRP RGRP
+#endif
+#ifndef S_IWGRP
+# define S_IWGRP WGRP
+#endif
+#ifndef S_IXGRP
+# define S_IXGRP XGRP
+#endif
+#ifndef S_IROTH
+# define S_IROTH ROTH
+#endif
+#ifndef S_IWOTH
+# define S_IWOTH WOTH
+#endif
+#ifndef S_IXOTH
+# define S_IXOTH XOTH
+#endif
+#ifndef S_IRWXU
+# define S_IRWXU (S_IRUSR | S_IWUSR | S_IXUSR)
+#endif
+#ifndef S_IRWXG
+# define S_IRWXG (S_IRGRP | S_IWGRP | S_IXGRP)
+#endif
+#ifndef S_IRWXO
+# define S_IRWXO (S_IROTH | S_IWOTH | S_IXOTH)
+#endif
+
+/* All the mode bits that can be affected by chmod. */
+#define CHMOD_MODE_BITS \
+ (S_ISUID | S_ISGID | S_ISVTX | S_IRWXU | S_IRWXG | S_IRWXO)
+
/* Return newly allocated memory to hold one element of type TYPE. */
#define talloc(type) ((type *) malloc (sizeof (type)))
-#define isodigit(c) ((c) >= '0' && (c) <= '7')
+/* Create a mode_change entry with the specified `=ddd'-style
+ mode change operation, where NEW_MODE is `ddd'. Return the
+ new entry, or NULL upon failure. */
+
+static struct mode_change *
+make_node_op_equals (mode_t new_mode)
+{
+ struct mode_change *p;
+ p = talloc (struct mode_change);
+ if (p == NULL)
+ return p;
+ p->next = NULL;
+ p->op = '=';
+ p->flags = 0;
+ p->value = new_mode;
+ p->affected = CHMOD_MODE_BITS; /* Affect all permissions. */
+ return p;
+}
-static int oatoi ();
+/* Append entry E to the end of the link list with the specified
+ HEAD and TAIL. */
+
+static void
+mode_append_entry (struct mode_change **head,
+ struct mode_change **tail,
+ struct mode_change *e)
+{
+ if (*head == NULL)
+ *head = *tail = e;
+ else
+ {
+ (*tail)->next = e;
+ *tail = e;
+ }
+}
/* Return a linked list of file mode change operations created from
MODE_STRING, an ASCII string that contains either an octal number
return MODE_MEMORY_EXHAUSTED if there is insufficient memory. */
struct mode_change *
-mode_compile (mode_string, masked_ops)
- const char *mode_string;
- unsigned masked_ops;
+mode_compile (const char *mode_string, unsigned int masked_ops)
{
struct mode_change *head; /* First element of the linked list. */
- struct mode_change *change; /* An element of the linked list. */
- int i; /* General purpose temporary. */
- int umask_value; /* The umask value (surprise). */
- unsigned short affected_bits; /* Which bits in the mode are operated on. */
- unsigned short affected_masked; /* `affected_bits' modified by umask. */
- unsigned ops_to_mask; /* Operators to actually use umask on. */
-
- i = oatoi (mode_string);
- if (i >= 0)
+ struct mode_change *tail; /* An element of the linked list. */
+ unsigned long octal_value; /* The mode value, if octal. */
+ mode_t umask_value; /* The umask value (surprise). */
+
+ head = NULL;
+#ifdef lint
+ tail = NULL;
+#endif
+
+ if (xstrtoul (mode_string, NULL, 8, &octal_value, "") == LONGINT_OK)
{
- if (i > 07777)
+ struct mode_change *p;
+ mode_t mode;
+ if (octal_value != (octal_value & ALLM))
return MODE_INVALID;
- head = talloc (struct mode_change);
- if (head == NULL)
+
+ /* Help the compiler optimize the usual case where mode_t uses
+ the traditional octal representation. */
+ mode = ((S_ISUID == SUID && S_ISGID == SGID && S_ISVTX == SVTX
+ && S_IRUSR == RUSR && S_IWUSR == WUSR && S_IXUSR == XUSR
+ && S_IRGRP == RGRP && S_IWGRP == WGRP && S_IXGRP == XGRP
+ && S_IROTH == ROTH && S_IWOTH == WOTH && S_IXOTH == XOTH)
+ ? octal_value
+ : (mode_t) ((octal_value & SUID ? S_ISUID : 0)
+ | (octal_value & SGID ? S_ISGID : 0)
+ | (octal_value & SVTX ? S_ISVTX : 0)
+ | (octal_value & RUSR ? S_IRUSR : 0)
+ | (octal_value & WUSR ? S_IWUSR : 0)
+ | (octal_value & XUSR ? S_IXUSR : 0)
+ | (octal_value & RGRP ? S_IRGRP : 0)
+ | (octal_value & WGRP ? S_IWGRP : 0)
+ | (octal_value & XGRP ? S_IXGRP : 0)
+ | (octal_value & ROTH ? S_IROTH : 0)
+ | (octal_value & WOTH ? S_IWOTH : 0)
+ | (octal_value & XOTH ? S_IXOTH : 0)));
+
+ p = make_node_op_equals (mode);
+ if (p == NULL)
return MODE_MEMORY_EXHAUSTED;
- head->next = NULL;
- head->op = '=';
- head->flags = 0;
- head->value = i;
- head->affected = 07777; /* Affect all permissions. */
+ mode_append_entry (&head, &tail, p);
return head;
}
umask_value = umask (0);
umask (umask_value); /* Restore the old value. */
-
- head = NULL;
-#ifdef lint
- change = NULL;
-#endif
--mode_string;
/* One loop iteration for each "ugoa...=+-rwxXstugo...[=+-rwxXstugo...]". */
do
{
- affected_bits = 0;
- ops_to_mask = 0;
+ /* Which bits in the mode are operated on. */
+ mode_t affected_bits = 0;
+ /* `affected_bits' modified by umask. */
+ mode_t affected_masked;
+ /* Operators to actually use umask on. */
+ unsigned int ops_to_mask = 0;
+
+ bool who_specified_p;
+
/* Turn on all the bits in `affected_bits' for each group given. */
for (++mode_string;; ++mode_string)
switch (*mode_string)
{
case 'u':
- affected_bits |= 04700;
+ affected_bits |= S_ISUID | S_IRWXU;
break;
case 'g':
- affected_bits |= 02070;
+ affected_bits |= S_ISGID | S_IRWXG;
break;
case 'o':
- affected_bits |= 01007;
+ affected_bits |= S_ISVTX | S_IRWXO;
break;
case 'a':
- affected_bits |= 07777;
+ affected_bits |= CHMOD_MODE_BITS;
break;
default:
goto no_more_affected;
no_more_affected:
/* If none specified, affect all bits, except perhaps those
set in the umask. */
- if (affected_bits == 0)
+ if (affected_bits)
+ who_specified_p = true;
+ else
{
- affected_bits = 07777;
+ who_specified_p = false;
+ affected_bits = CHMOD_MODE_BITS;
ops_to_mask = masked_ops;
}
while (*mode_string == '=' || *mode_string == '+' || *mode_string == '-')
{
- /* Add the element to the tail of the list, so the operations
- are performed in the correct order. */
- if (head == NULL)
+ struct mode_change *change = talloc (struct mode_change);
+ if (change == NULL)
{
- head = talloc (struct mode_change);
- if (head == NULL)
- return MODE_MEMORY_EXHAUSTED;
- change = head;
- }
- else
- {
- change->next = talloc (struct mode_change);
- if (change->next == NULL)
- {
- mode_free (change);
- return MODE_MEMORY_EXHAUSTED;
- }
- change = change->next;
+ mode_free (head);
+ return MODE_MEMORY_EXHAUSTED;
}
change->next = NULL;
change->op = *mode_string; /* One of "=+-". */
affected_masked = affected_bits;
+
+ /* Per the Single Unix Spec, if `who' is not specified and the
+ `=' operator is used, then clear all the bits first. */
+ if (!who_specified_p &&
+ ops_to_mask & (*mode_string == '=' ? MODE_MASK_EQUALS : 0))
+ {
+ struct mode_change *p = make_node_op_equals (0);
+ if (p == NULL)
+ return MODE_MEMORY_EXHAUSTED;
+ mode_append_entry (&head, &tail, p);
+ }
+
if (ops_to_mask & (*mode_string == '=' ? MODE_MASK_EQUALS
: *mode_string == '+' ? MODE_MASK_PLUS
: MODE_MASK_MINUS))
change->value = 0;
change->flags = 0;
+ /* Add the element to the tail of the list, so the operations
+ are performed in the correct order. */
+ mode_append_entry (&head, &tail, change);
+
/* Set `value' according to the bits set in `affected_masked'. */
for (++mode_string;; ++mode_string)
switch (*mode_string)
{
case 'r':
- change->value |= 00444 & affected_masked;
+ change->value |= ((S_IRUSR | S_IRGRP | S_IROTH)
+ & affected_masked);
break;
case 'w':
- change->value |= 00222 & affected_masked;
+ change->value |= ((S_IWUSR | S_IWGRP | S_IWOTH)
+ & affected_masked);
break;
case 'X':
change->flags |= MODE_X_IF_ANY_X;
/* Fall through. */
case 'x':
- change->value |= 00111 & affected_masked;
+ change->value |= ((S_IXUSR | S_IXGRP | S_IXOTH)
+ & affected_masked);
break;
case 's':
/* Set the setuid/gid bits if `u' or `g' is selected. */
- change->value |= 06000 & affected_masked;
+ change->value |= (S_ISUID | S_ISGID) & affected_masked;
break;
case 't':
/* Set the "save text image" bit if `o' is selected. */
- change->value |= 01000 & affected_masked;
+ change->value |= S_ISVTX & affected_masked;
break;
case 'u':
/* Set the affected bits to the value of the `u' bits
on the same file. */
if (change->value)
goto invalid;
- change->value = 00700;
+ change->value = S_IRWXU;
change->flags |= MODE_COPY_EXISTING;
break;
case 'g':
on the same file. */
if (change->value)
goto invalid;
- change->value = 00070;
+ change->value = S_IRWXG;
change->flags |= MODE_COPY_EXISTING;
break;
case 'o':
on the same file. */
if (change->value)
goto invalid;
- change->value = 00007;
+ change->value = S_IRWXO;
change->flags |= MODE_COPY_EXISTING;
break;
default:
return MODE_INVALID;
}
-/* Return a file mode change operation created from the reference REF_FILE
- Don't affect special permissions, use umask, affect 'x' if any 'x', for
- maximum security
-
- Return MODE_BAD_REFERENCE if REF_FILE can't be accessed */
+/* Return a file mode change operation that sets permissions to match those
+ of REF_FILE. Return MODE_BAD_REFERENCE if REF_FILE can't be accessed. */
struct mode_change *
-mode_create_from_ref (ref_file)
- const char *ref_file;
+mode_create_from_ref (const char *ref_file)
{
struct mode_change *change; /* the only change element */
struct stat ref_stats;
- int i;
- int umask_value;
if (stat (ref_file, &ref_stats))
return MODE_BAD_REFERENCE;
if (change == NULL)
return MODE_MEMORY_EXHAUSTED;
- umask_value = umask (0);
- umask (umask_value);
-
change->op = '=';
- change->flags = MODE_X_IF_ANY_X;
- change->affected = 0777 & ~umask_value;
+ change->flags = 0;
+ change->affected = CHMOD_MODE_BITS;
change->value = ref_stats.st_mode;
change->next = NULL;
change affects it even if no execute bits were set in OLDMODE.
The returned value has the S_IFMT bits cleared. */
-unsigned short
-mode_adjust (oldmode, changes)
- unsigned oldmode;
- const struct mode_change *changes;
+mode_t
+mode_adjust (mode_t oldmode, const struct mode_change *changes)
{
- unsigned short newmode; /* The adjusted mode and one operand. */
- unsigned short value; /* The other operand. */
+ mode_t newmode; /* The adjusted mode and one operand. */
+ mode_t value; /* The other operand. */
- newmode = oldmode & 07777;
+ newmode = oldmode & CHMOD_MODE_BITS;
for (; changes; changes = changes->next)
{
the mask `changes->value'. */
value = newmode & changes->value;
- if (changes->value & 00700)
+ if (changes->value & S_IRWXU)
/* Copy `u' permissions onto `g' and `o'. */
- value |= (value >> 3) | (value >> 6);
- else if (changes->value & 00070)
+ value |= ( (value & S_IRUSR ? S_IRGRP | S_IROTH : 0)
+ | (value & S_IWUSR ? S_IWGRP | S_IWOTH : 0)
+ | (value & S_IXUSR ? S_IXGRP | S_IXOTH : 0));
+ else if (changes->value & S_IRWXG)
/* Copy `g' permissions onto `u' and `o'. */
- value |= (value << 3) | (value >> 3);
+ value |= ( (value & S_IRGRP ? S_IRUSR | S_IROTH : 0)
+ | (value & S_IWGRP ? S_IWUSR | S_IWOTH : 0)
+ | (value & S_IXGRP ? S_IXUSR | S_IXOTH : 0));
else
/* Copy `o' permissions onto `u' and `g'. */
- value |= (value << 3) | (value << 6);
+ value |= ( (value & S_IROTH ? S_IRUSR | S_IRGRP : 0)
+ | (value & S_IWOTH ? S_IWUSR | S_IWGRP : 0)
+ | (value & S_IXOTH ? S_IXUSR | S_IXGRP : 0));
/* In order to change only `u', `g', or `o' permissions,
or some combination thereof, clear unselected bits.
- This can not be done in mode_compile because the value
+ This cannot be done in mode_compile because the value
to which the `changes->affected' mask is applied depends
on the old mode of each file. */
value &= changes->affected;
directory and no execute bits are already set. */
if ((changes->flags & MODE_X_IF_ANY_X)
&& !S_ISDIR (oldmode)
- && (newmode & 00111) == 0)
- value &= ~00111; /* Clear the execute bits. */
+ && (newmode & (S_IXUSR | S_IXGRP | S_IXOTH)) == 0)
+ /* Clear the execute bits. */
+ value &= ~ (S_IXUSR | S_IXGRP | S_IXOTH);
}
switch (changes->op)
CHANGES. */
void
-mode_free (changes)
- register struct mode_change *changes;
+mode_free (register struct mode_change *changes)
{
register struct mode_change *next;
changes = next;
}
}
-
-/* Return a positive integer containing the value of the ASCII
- octal number S. If S is not an octal number, return -1. */
-
-static int
-oatoi (s)
- char *s;
-{
- register int i;
-
- if (*s == 0)
- return -1;
- for (i = 0; isodigit (*s); ++s)
- i = i * 8 + *s - '0';
- if (*s)
- return -1;
- return i;
-}