X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fuserspec.c;h=80ace3e237181b34fb7b70a10954d599bc5e718d;hb=66949d7f384e69e0b37b1753f4d2bed33fb0a8de;hp=37b7980b9f59b8ee62d6d9147f1fd50024d23946;hpb=9d3b49b8a24423725aa3da686f391dd50372fdb0;p=gnulib.git diff --git a/lib/userspec.c b/lib/userspec.c index 37b7980b9..80ace3e23 100644 --- a/lib/userspec.c +++ b/lib/userspec.c @@ -1,5 +1,5 @@ /* userspec.c -- Parse a user and group string. - Copyright (C) 1989, 1990, 1991, 1992 Free Software Foundation, Inc. + Copyright (C) 1989-1992, 1997-1998, 2000, 2002-2003 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 @@ -12,180 +12,354 @@ 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., 675 Mass Ave, Cambridge, MA 02139, USA. */ + along with this program; if not, write to the Free Software Foundation, + Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /* Written by David MacKenzie . */ - -#ifdef HAVE_CONFIG_H -#if defined (CONFIG_BROKETS) -/* We use instead of "config.h" so that a compilation - using -I. -I$srcdir will use ./config.h rather than $srcdir/config.h - (which it would do because it found this file in $srcdir). */ -#include -#else -#include "config.h" -#endif + +#if HAVE_CONFIG_H +# include #endif +#include + #include #include #include #include -#if defined(STDC_HEADERS) || defined(HAVE_STRING_H) -#include -#ifndef index -#define index strchr +#if HAVE_SYS_PARAM_H +# include #endif + +#include + +#if HAVE_STRING_H +# include #else -#include +# include +# ifndef strchr +# define strchr index +# endif #endif -#ifdef STDC_HEADERS -#include -#else -char *malloc (); +#if STDC_HEADERS +# include #endif -#ifdef HAVE_UNISTD_H -#include +#if HAVE_UNISTD_H +# include #endif +#include "xalloc.h" +#include "xstrtol.h" + +#include "gettext.h" +#define _(msgid) gettext (msgid) +#define N_(msgid) msgid + #ifndef _POSIX_VERSION struct passwd *getpwnam (); struct group *getgrnam (); struct group *getgrgid (); #endif -#ifdef _POSIX_SOURCE -#define endpwent() -#define endgrent() +#ifndef HAVE_ENDGRENT +# define endgrent() ((void) 0) +#endif + +#ifndef HAVE_ENDPWENT +# define endpwent() ((void) 0) #endif -#define isdigit(c) ((c) >= '0' && (c) <= '9') +/* The extra casts work around common compiler bugs. */ +#define TYPE_SIGNED(t) (! ((t) 0 < (t) -1)) +/* The outer cast is needed to work around a bug in Cray C 5.0.3.0. + It is necessary at least when t == time_t. */ +#define TYPE_MINIMUM(t) ((t) (TYPE_SIGNED (t) \ + ? ~ (t) 0 << (sizeof (t) * CHAR_BIT - 1) : (t) 0)) +#define TYPE_MAXIMUM(t) ((t) (~ (t) 0 - TYPE_MINIMUM (t))) + +#ifndef UID_T_MAX +# define UID_T_MAX TYPE_MAXIMUM (uid_t) +#endif + +#ifndef GID_T_MAX +# define GID_T_MAX TYPE_MAXIMUM (gid_t) +#endif + +/* MAXUID may come from limits.h or sys/params.h. */ +#ifndef MAXUID +# define MAXUID UID_T_MAX +#endif +#ifndef MAXGID +# define MAXGID GID_T_MAX +#endif + +/* Perform the equivalent of the statement `dest = strdup (src);', + but obtaining storage via alloca instead of from the heap. */ + +#define V_STRDUP(dest, src) \ + do \ + { \ + int _len = strlen ((src)); \ + (dest) = (char *) alloca (_len + 1); \ + strcpy (dest, src); \ + } \ + while (0) + +/* ISDIGIT differs from isdigit, as follows: + - Its arg may be any int or unsigned int; it need not be an unsigned char. + - It's guaranteed to evaluate its argument exactly once. + - It's typically faster. + POSIX says that only '0' through '9' are digits. Prefer ISDIGIT to + ISDIGIT_LOCALE unless it's important to use the locale's definition + of `digit' even when the host does not conform to POSIX. */ +#define ISDIGIT(c) ((unsigned) (c) - '0' <= 9) +#ifndef strdup char *strdup (); -static int isnumber (); +#endif + +/* Return nonzero if STR represents an unsigned decimal integer, + otherwise return 0. */ + +static int +is_number (const char *str) +{ + for (; *str; str++) + if (!ISDIGIT (*str)) + return 0; + return 1; +} /* Extract from NAME, which has the form "[user][:.][group]", a USERNAME, UID U, GROUPNAME, and GID G. Either user or group, or both, must be present. - If the group is omitted but the ":" or "." separator is given, + If the group is omitted but the ":" separator is given, use the given user's login group. + If SPEC_ARG contains a `:', then use that as the separator, ignoring + any `.'s. If there is no `:', but there is a `.', then first look + up the entire SPEC_ARG as a login name. If that look-up fails, then + try again interpreting the `.' as a separator. USERNAME and GROUPNAME will be in newly malloc'd memory. Either one might be NULL instead, indicating that it was not given and the corresponding numeric ID was left unchanged. - Might write NULs into NAME. Return NULL if successful, a static error message string if not. */ -char * -parse_user_spec (name, uid, gid, username, groupname) - char *name; - uid_t *uid; - gid_t *gid; - char **username, **groupname; +const char * +parse_user_spec (const char *spec_arg, uid_t *uid, gid_t *gid, + char **username_arg, char **groupname_arg) { - static char *tired = "virtual memory exhausted"; + static const char *E_invalid_user = N_("invalid user"); + static const char *E_invalid_group = N_("invalid group"); + static const char *E_bad_spec = + N_("cannot get the login group of a numeric UID"); + static const char *E_cannot_omit_both = + N_("cannot omit both user and group"); + + const char *error_msg; + char *spec; /* A copy we can write on. */ struct passwd *pwd; struct group *grp; - char *cp; - int use_login_group = 0; + char *g, *u, *separator; + char *groupname; + int maybe_retry = 0; + char *dot = NULL; + + error_msg = NULL; + *username_arg = *groupname_arg = NULL; + groupname = NULL; + + V_STRDUP (spec, spec_arg); + + /* Find the POSIX `:' separator if there is one. */ + separator = strchr (spec, ':'); + + /* If there is no colon, then see if there's a `.'. */ + if (separator == NULL) + { + dot = strchr (spec, '.'); + /* If there's no colon but there is a `.', then first look up the + whole spec, in case it's an OWNER name that includes a dot. + If that fails, then we'll try again, but interpreting the `.' + as a separator. */ + /* FIXME: accepting `.' as the separator is contrary to POSIX. + someday we should drop support for this. */ + if (dot) + maybe_retry = 1; + } + + retry: + + /* Replace separator with a NUL. */ + if (separator != NULL) + *separator = '\0'; + + /* Set U and G to non-zero length strings corresponding to user and + group specifiers or to NULL. */ + u = (*spec == '\0' ? NULL : spec); - *username = *groupname = NULL; + g = (separator == NULL || *(separator + 1) == '\0' + ? NULL + : separator + 1); - /* Check whether a group is given. */ - cp = index (name, ':'); - if (cp == NULL) - cp = index (name, '.'); - if (cp != NULL) + if (u == NULL && g == NULL) + return _(E_cannot_omit_both); + +#ifdef __DJGPP__ + /* Pretend that we are the user U whose group is G. This makes + pwd and grp functions ``know'' about the UID and GID of these. */ + if (u && !is_number (u)) + setenv ("USER", u, 1); + if (g && !is_number (g)) + setenv ("GROUP", g, 1); +#endif + + if (u != NULL) { - *cp++ = '\0'; - if (*cp == '\0') + pwd = getpwnam (u); + if (pwd == NULL) { - if (cp == name + 1) - /* Neither user nor group given, just "." or ":". */ - return "can not omit both user and group"; + + if (!is_number (u)) + error_msg = E_invalid_user; else - /* "user.". */ - use_login_group = 1; + { + int use_login_group; + use_login_group = (separator != NULL && g == NULL); + if (use_login_group) + error_msg = E_bad_spec; + else + { + unsigned long int tmp_long; + if (xstrtoul (u, NULL, 0, &tmp_long, NULL) != LONGINT_OK + || tmp_long > MAXUID) + return _(E_invalid_user); + *uid = tmp_long; + } + } } else { - /* Explicit group. */ - *groupname = strdup (cp); - if (*groupname == NULL) - return tired; - grp = getgrnam (cp); - if (grp == NULL) + *uid = pwd->pw_uid; + if (g == NULL && separator != NULL) { - if (!isnumber (cp)) - return "invalid group"; - *gid = atoi (cp); + /* A separator was given, but a group was not specified, + so get the login group. */ + *gid = pwd->pw_gid; + grp = getgrgid (pwd->pw_gid); + if (grp == NULL) + { + /* This is enough room to hold the unsigned decimal + representation of any 32-bit quantity and the trailing + zero byte. */ + char uint_buf[21]; + sprintf (uint_buf, "%u", (unsigned) (pwd->pw_gid)); + V_STRDUP (groupname, uint_buf); + } + else + { + V_STRDUP (groupname, grp->gr_name); + } + endgrent (); } - else - *gid = grp->gr_gid; - endgrent (); /* Save a file descriptor. */ } + endpwent (); } - /* Parse the user name, now that any group has been removed. */ - - if (name[0] == '\0') - /* No user name was given, just a group. */ - return NULL; - - *username = strdup (name); - if (*username == NULL) - return tired; - - pwd = getpwnam (name); - if (pwd == NULL) + if (g != NULL && error_msg == NULL) { - if (!isnumber (name)) - return "invalid user"; - if (use_login_group) - return "cannot get the login group of a numeric UID"; - *uid = atoi (name); - } - else - { - *uid = pwd->pw_uid; - if (use_login_group) + /* Explicit group. */ + grp = getgrnam (g); + if (grp == NULL) { - *gid = pwd->pw_gid; - grp = getgrgid (pwd->pw_gid); - if (grp == NULL) + if (!is_number (g)) + error_msg = E_invalid_group; + else { - *groupname = malloc (15); - if (*groupname == NULL) - return tired; - sprintf (*groupname, "%u", (unsigned) (pwd->pw_gid)); + unsigned long int tmp_long; + if (xstrtoul (g, NULL, 0, &tmp_long, NULL) != LONGINT_OK + || tmp_long > MAXGID) + return _(E_invalid_group); + *gid = tmp_long; } - else + } + else + *gid = grp->gr_gid; + endgrent (); /* Save a file descriptor. */ + + if (error_msg == NULL) + V_STRDUP (groupname, g); + } + + if (error_msg == NULL) + { + if (u != NULL) + { + *username_arg = strdup (u); + if (*username_arg == NULL) + error_msg = xalloc_msg_memory_exhausted; + } + + if (groupname != NULL && error_msg == NULL) + { + *groupname_arg = strdup (groupname); + if (*groupname_arg == NULL) { - *groupname = strdup (grp->gr_name); - if (*groupname == NULL) - return tired; + if (*username_arg != NULL) + { + free (*username_arg); + *username_arg = NULL; + } + error_msg = xalloc_msg_memory_exhausted; } - endgrent (); } } - endpwent (); - return NULL; + + if (error_msg && maybe_retry) + { + maybe_retry = 0; + separator = dot; + error_msg = NULL; + goto retry; + } + + return _(error_msg); } -/* Return nonzero if STR represents an unsigned decimal integer, - otherwise return 0. */ +#ifdef TEST -static int -isnumber (str) - char *str; +# define NULL_CHECK(s) ((s) == NULL ? "(null)" : (s)) + +int +main (int argc, char **argv) { - for (; *str; str++) - if (!isdigit (*str)) - return 0; - return 1; + int i; + + for (i = 1; i < argc; i++) + { + const char *e; + char *username, *groupname; + uid_t uid; + gid_t gid; + char *tmp; + + tmp = strdup (argv[i]); + e = parse_user_spec (tmp, &uid, &gid, &username, &groupname); + free (tmp); + printf ("%s: %u %u %s %s %s\n", + argv[i], + (unsigned int) uid, + (unsigned int) gid, + NULL_CHECK (username), + NULL_CHECK (groupname), + NULL_CHECK (e)); + } + + exit (0); } + +#endif