-/* setgrp.c - by Michael Haardt. Set the gid if possible */
-/* Added a bit more error recovery/reporting - poe */
-/* Vesa Roukonen added code for asking password */
-/* Currently maintained at ftp://ftp.daimi.aau.dk/pub/linux/poe/ */
+/* setgrp.c - by Michael Haardt. Set the gid if possible
+ * Added a bit more error recovery/reporting - poe
+ * Vesa Roukonen added code for asking password */
-/* 1999-02-22 Arkadiusz Mi¶kiewicz <misiek@pld.ORG.PL>
+/* 1999-02-22 Arkadiusz Miśkiewicz <misiek@pld.ORG.PL>
* - added Native Language Support
*/
-#include <unistd.h>
-#include <pwd.h>
+#include <errno.h>
+#include <getopt.h>
#include <grp.h>
-#include <string.h>
+#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
-#include <errno.h>
+#include <string.h>
+#include <termios.h>
+#include <unistd.h>
#ifdef HAVE_CRYPT_H
-#include <crypt.h>
+# include <crypt.h>
+#endif
+
+#ifdef HAVE_GETSGNAM
+# include <gshadow.h>
#endif
#include "c.h"
-#include "pathnames.h"
+#include "closestream.h"
#include "nls.h"
+#include "pathnames.h"
+#include "xalloc.h"
+
+static char *xgetpass(FILE *input, const char *prompt)
+{
+ char *pass = NULL;
+ struct termios saved, no_echo;
+ const int fd = fileno(input);
+ size_t dummy = 0;
+ ssize_t len;
+
+ fputs(prompt, stdout);
+ if (isatty(fd)) {
+ /* disable echo */
+ tcgetattr(fd, &saved);
+ no_echo = saved;
+ no_echo.c_lflag &= ~ECHO;
+ no_echo.c_lflag |= ECHONL;
+ if (tcsetattr(fd, TCSANOW, &no_echo))
+ err(EXIT_FAILURE, _("could not set terminal attributes"));
+ }
+ len = getline(&pass, &dummy, input);
+ if (isatty(fd))
+ /* restore terminal */
+ if (tcsetattr(fd, TCSANOW, &saved))
+ err(EXIT_FAILURE, _("could not set terminal attributes"));
+ if (len < 0)
+ err(EXIT_FAILURE, _("getline() failed"));
+ if (0 < len && *(pass + len - 1) == '\n')
+ *(pass + len - 1) = '\0';
+ return pass;
+}
+
+#ifndef HAVE_EXPLICIT_BZERO
+/* Ensure memory is set to value c without compiler optimization getting
+ * into way that could happen with memset(3). */
+static int xmemset_s(void *v, size_t sz, const int c)
+{
+ volatile unsigned char *p = v;
+
+ if (v == NULL)
+ return EINVAL;
+ while (sz--)
+ *p++ = c;
+ return 0;
+}
+#endif
/* try to read password from gshadow */
-static char *
-get_gshadow_pwd(char *groupname)
+static char *get_gshadow_pwd(const char *groupname)
{
+#ifdef HAVE_GETSGNAM
+ struct sgrp *sgrp;
+
+ sgrp = getsgnam(groupname);
+ return sgrp ? xstrdup(sgrp->sg_passwd) : NULL;
+#else
char buf[BUFSIZ];
char *pwd = NULL;
- FILE *f = fopen(_PATH_GSHADOW, "r");
+ FILE *f;
- if (groupname == NULL || *groupname == '\0' || f == NULL)
+ if (groupname == NULL || *groupname == '\0')
return NULL;
- while(fgets(buf, sizeof buf, f))
- {
- char *cp = strchr (buf, ':');
+ f = fopen(_PATH_GSHADOW, "r");
+ if (!f)
+ return NULL;
+
+ while (fgets(buf, sizeof buf, f)) {
+ char *cp = strchr(buf, ':');
if (!cp)
- continue; /* any junk in gshadow? */
+ /* any junk in gshadow? */
+ continue;
*cp = '\0';
- if (strcmp(buf, groupname) == 0)
- {
- if (cp-buf >= BUFSIZ)
- break; /* only group name on line */
- pwd = cp+1;
- if ((cp = strchr(pwd, ':')) && pwd == cp+1 )
- pwd = NULL; /* empty password */
+ if (strcmp(buf, groupname) == 0) {
+ if (cp - buf >= BUFSIZ)
+ /* only group name on line */
+ break;
+ pwd = cp + 1;
+ if ((cp = strchr(pwd, ':')) && pwd == cp + 1)
+ /* empty password */
+ pwd = NULL;
else if (cp)
*cp = '\0';
break;
}
}
fclose(f);
- return pwd ? strdup(pwd) : NULL;
+ return pwd ? xstrdup(pwd) : NULL;
+#endif /* HAVE_GETSGNAM */
}
-static int
-allow_setgid(struct passwd *pe, struct group *ge)
+static int allow_setgid(const struct passwd *pe, const struct group *ge)
{
- char **look;
- int notfound = 1;
- char *pwd, *xpwd;
-
- if (getuid() == 0) return TRUE; /* root may do anything */
- if (ge->gr_gid == pe->pw_gid) return TRUE; /* You can switch back to your default group */
-
- look = ge->gr_mem;
- while (*look && (notfound = strcmp(*look++,pe->pw_name)));
-
- if(!notfound) return TRUE; /* member of group => OK */
+ char **look;
+ int notfound = 1;
+ char *pwd, *xpwd;
+
+ if (getuid() == 0)
+ /* root may do anything */
+ return TRUE;
+ if (ge->gr_gid == pe->pw_gid)
+ /* You can switch back to your default group */
+ return TRUE;
+
+ look = ge->gr_mem;
+ while (*look && (notfound = strcmp(*look++, pe->pw_name))) ;
+
+ if (!notfound)
+ /* member of group => OK */
+ return TRUE;
+
+ /* Ask for password. Often there is no password in /etc/group, so
+ * contrary to login et al. we let an empty password mean the same
+ * as in /etc/passwd */
+
+ /* check /etc/gshadow */
+ if (!(pwd = get_gshadow_pwd(ge->gr_name)))
+ pwd = ge->gr_passwd;
+
+ if (pwd && *pwd && (xpwd = xgetpass(stdin, _("Password: ")))) {
+ char *cbuf = crypt(xpwd, pwd);
+
+#ifdef HAVE_EXPLICIT_BZERO
+ explicit_bzero(xpwd, strlen(xpwd));
+#else
+ xmemset_s(xpwd, strlen(xpwd), 0);
+#endif
+ free(xpwd);
+ if (!cbuf)
+ warn(_("crypt failed"));
+ else if (strcmp(pwd, cbuf) == 0)
+ return TRUE;
+ }
- /* Ask for password. Often there is no password in /etc/group, so
- contrary to login et al. we let an empty password mean the same
- as * in /etc/passwd */
+ /* default to denial */
+ return FALSE;
+}
- /* check /etc/gshadow */
- if (!(pwd = get_gshadow_pwd(ge->gr_name)))
- pwd = ge->gr_passwd;
+static void __attribute__((__noreturn__)) usage(void)
+{
+ FILE *out = stdout;
+ fputs(USAGE_HEADER, out);
+ fprintf(out, _(" %s <group>\n"), program_invocation_short_name);
- if(pwd && *pwd && (xpwd = getpass(_("Password: ")))) {
- if(strcmp(pwd, crypt(xpwd, pwd)) == 0)
- return TRUE; /* password accepted */
- }
+ fputs(USAGE_SEPARATOR, out);
+ fputs(_("Log in to a new group.\n"), out);
- return FALSE; /* default to denial */
+ fputs(USAGE_OPTIONS, out);
+ printf(USAGE_HELP_OPTIONS(16));
+ printf(USAGE_MAN_TAIL("newgrp(1)"));
+ exit(EXIT_SUCCESS);
}
-int
-main(int argc, char *argv[])
+int main(int argc, char *argv[])
{
- struct passwd *pw_entry;
- struct group *gr_entry;
- char *shell;
-
- setlocale(LC_ALL, "");
- bindtextdomain(PACKAGE, LOCALEDIR);
- textdomain(PACKAGE);
-
- if (!(pw_entry = getpwuid(getuid())))
- err(EXIT_FAILURE, _("who are you?"));
-
- shell = (pw_entry->pw_shell[0] ? pw_entry->pw_shell : _PATH_BSHELL);
-
- if (argc < 2) {
- if(setgid(pw_entry->pw_gid) < 0)
- err(EXIT_FAILURE, _("setgid failed"));
- } else {
- errno = 0;
- if (!(gr_entry = getgrnam(argv[1]))) {
- if (errno)
- err(EXIT_FAILURE, _("no such group"));
- else
- errx(EXIT_FAILURE, _("no such group")); /* No group */
+ struct passwd *pw_entry;
+ struct group *gr_entry;
+ char *shell;
+ int ch;
+ static const struct option longopts[] = {
+ {"version", no_argument, NULL, 'V'},
+ {"help", no_argument, NULL, 'h'},
+ {NULL, 0, NULL, 0}
+ };
+
+ setlocale(LC_ALL, "");
+ bindtextdomain(PACKAGE, LOCALEDIR);
+ textdomain(PACKAGE);
+ close_stdout_atexit();
+
+ while ((ch = getopt_long(argc, argv, "Vh", longopts, NULL)) != -1)
+ switch (ch) {
+ case 'V':
+ print_version(EXIT_SUCCESS);
+ case 'h':
+ usage();
+ default:
+ errtryhelp(EXIT_FAILURE);
+ }
+
+ if (!(pw_entry = getpwuid(getuid())))
+ err(EXIT_FAILURE, _("who are you?"));
+
+ if (argc < 2) {
+ if (setgid(pw_entry->pw_gid) < 0)
+ err(EXIT_FAILURE, _("setgid failed"));
} else {
- if (allow_setgid(pw_entry, gr_entry)) {
+ errno = 0;
+ if (!(gr_entry = getgrnam(argv[1]))) {
+ if (errno)
+ err(EXIT_FAILURE, _("no such group"));
+ else
+ errx(EXIT_FAILURE, _("no such group"));
+ }
+ if (!allow_setgid(pw_entry, gr_entry))
+ errx(EXIT_FAILURE, _("permission denied"));
if (setgid(gr_entry->gr_gid) < 0)
- err(EXIT_FAILURE, _("setgid failed"));
- } else
- errx(EXIT_FAILURE, _("permission denied"));
+ err(EXIT_FAILURE, _("setgid failed"));
}
- }
-
- if (setuid(getuid()) < 0)
- err(EXIT_FAILURE, _("setuid failed"));
- fflush(stdout); fflush(stderr);
- execl(shell,shell,(char*)0);
- warn(_("exec %s failed"), shell);
- fflush(stderr);
+ if (setuid(getuid()) < 0)
+ err(EXIT_FAILURE, _("setuid failed"));
- return EXIT_FAILURE;
+ fflush(NULL);
+ shell = (pw_entry->pw_shell && *pw_entry->pw_shell ?
+ pw_entry->pw_shell : _PATH_BSHELL);
+ execl(shell, shell, (char *)0);
+ errexec(shell);
}
projects / thirdparty / util-linux.git / blobdiff