Adding upstream version 2.38.1.upstream/2.38.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 241 insertions, 0 deletions

diff --git a/login-utils/newgrp.c b/login-utils/newgrp.c
new file mode 100644
index 0000000..2acbc91
--- /dev/null
+++ b/login-utils/newgrp.c
@@ -0,0 +1,241 @@
+/* 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 Miśkiewicz <misiek@pld.ORG.PL>
+ * - added Native Language Support
+ */
+
+#include <errno.h>
+#include <getopt.h>
+#include <grp.h>
+#include <pwd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <termios.h>
+#include <unistd.h>
+
+#ifdef HAVE_CRYPT_H
+# include <crypt.h>
+#endif
+
+#ifdef HAVE_GETSGNAM
+# include <gshadow.h>
+#endif
+
+#include "c.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(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;
+
+	if (groupname == NULL || *groupname == '\0')
+		return NULL;
+
+	f = fopen(_PATH_GSHADOW, "r");
+	if (!f)
+		return NULL;
+
+	while (fgets(buf, sizeof buf, f)) {
+		char *cp = strchr(buf, ':');
+		if (!cp)
+			/* any junk in gshadow? */
+			continue;
+		*cp = '\0';
+		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 ? xstrdup(pwd) : NULL;
+#endif	/* HAVE_GETSGNAM */
+}
+
+static int allow_setgid(const struct passwd *pe, const struct group *ge)
+{
+	char **look;
+	int notfound = 1;
+	char *pwd, *xpwd, *spwd;
+
+	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 */
+	spwd = get_gshadow_pwd(ge->gr_name);
+	pwd = spwd ? spwd : 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;
+	}
+
+	free(spwd);
+
+	/* default to denial */
+	return FALSE;
+}
+
+static void __attribute__((__noreturn__)) usage(void)
+{
+	FILE *out = stdout;
+	fputs(USAGE_HEADER, out);
+	fprintf(out, _(" %s <group>\n"), program_invocation_short_name);
+
+	fputs(USAGE_SEPARATOR, out);
+	fputs(_("Log in to a new group.\n"), out);
+
+	fputs(USAGE_OPTIONS, out);
+	printf(USAGE_HELP_OPTIONS(16));
+	printf(USAGE_MAN_TAIL("newgrp(1)"));
+	exit(EXIT_SUCCESS);
+}
+
+int main(int argc, char *argv[])
+{
+	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 {
+		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"));
+	}
+
+	if (setuid(getuid()) < 0)
+		err(EXIT_FAILURE, _("setuid failed"));
+
+	fflush(NULL);
+	shell = (pw_entry->pw_shell && *pw_entry->pw_shell ?
+				pw_entry->pw_shell : _PATH_BSHELL);
+	execl(shell, shell, (char *)NULL);
+	errexec(shell);
+}