changeset 642:812afb883392

Minor cleanups, mostly whitespace.
author Rob Landley <rob@landley.net>
date Tue, 24 Jul 2012 02:52:36 -0500
parents 94f189961631
children 7bdebd2af1d6
files toys/login.c
diffstat 1 files changed, 40 insertions(+), 85 deletions(-) [+]
line wrap: on
line diff
--- a/toys/login.c	Mon Jul 23 23:55:34 2012 -0500
+++ b/toys/login.c	Tue Jul 24 02:52:36 2012 -0500
@@ -30,7 +30,7 @@
 #define HOSTNAME_SIZE 32
 
 DEFINE_GLOBALS(
-	char * hostname;
+	char *hostname;
 )
 #define TT this.login
 
@@ -40,7 +40,7 @@
 	exit(0);
 }
 
-static const char *forbid[] = {
+static char *forbid[] = {
 	"BASH_ENV",
 	"ENV",
 	"HOME",
@@ -57,30 +57,16 @@
 	NULL
 };
 
-// Unset dangerous environment variables.
-void sanitize_env()
-{
-	const char **p = forbid;
-	do {
-		unsetenv(*p);
-		p++;
-	} while (*p);
-}
-
 int verify_password(char * pwd)
 {
-	char * pass;
+	char *pass;
 
-	if (read_password(toybuf, sizeof(toybuf), "Password: "))
-		return 1;
-	if (!pwd)
-		return 1;
-	if (pwd[0] == '!' || pwd[0] == '*')
-		return 1;
+	if (read_password(toybuf, sizeof(toybuf), "Password: ")) return 1;
+	if (!pwd) return 1;
+	if (pwd[0] == '!' || pwd[0] == '*') return 1;
 
 	pass = crypt(toybuf, pwd);
-	if (pass != NULL && strcmp(pass, pwd)==0)
-		return 0;
+	if (pass && !strcmp(pass, pwd)) return 0;
 
 	return 1;
 }
@@ -90,8 +76,7 @@
 	char hostname[HOSTNAME_SIZE+1];
 	int i = 0;
 	hostname[HOSTNAME_SIZE] = 0;
-	if(!gethostname(hostname, HOSTNAME_SIZE))
-		fputs(hostname, stdout);
+	if(!gethostname(hostname, HOSTNAME_SIZE)) fputs(hostname, stdout);
 
 	fputs(" login: ", stdout);
 	fflush(stdout);
@@ -106,10 +91,7 @@
 		if(!fgets(&buff[1], HOSTNAME_SIZE-1, stdin))
 			_exit(1);
 
-	while(i<HOSTNAME_SIZE-1 && isgraph(buff[i]))
-	{
-		i++;
-	}
+	while(i<HOSTNAME_SIZE-1 && isgraph(buff[i])) i++;
 	buff[i] = 0;
 }
 
@@ -117,15 +99,12 @@
 {
 	int fd = open("/etc/nologin", O_RDONLY);
 	int size;
-	if (fd == -1)
-		return;
+	if (fd == -1) return;
 
 	size = readall(fd, toybuf,sizeof(toybuf)-1);
 	toybuf[size] = 0;
-	if (!size)
-		puts("System closed for routine maintenance\n");
-	else
-		puts(toybuf);
+	if (!size) puts("System closed for routine maintenance\n");
+	else puts(toybuf);
 
 	close(fd);
 	fflush(stdout);
@@ -136,8 +115,7 @@
 {
 	int fd = open("/etc/motd", O_RDONLY);
 	int size;
-	if (fd == -1)
-		return;
+	if (fd == -1) return;
 
 	size = readall(fd, toybuf,sizeof(toybuf)-1);
 	toybuf[size] = 0;
@@ -149,12 +127,9 @@
 
 int change_identity(const struct passwd *pwd)
 {
-	if (initgroups(pwd->pw_name,pwd->pw_gid))
-		return 1;
-	if (setgid(pwd->pw_uid))
-		return 1;
-	if (setuid(pwd->pw_uid))
-		return 1;
+	if (initgroups(pwd->pw_name,pwd->pw_gid)) return 1;
+	if (setgid(pwd->pw_uid)) return 1;
+	if (setuid(pwd->pw_uid)) return 1;
 
 	return 0;
 }
@@ -162,10 +137,8 @@
 void spawn_shell(const char *shell)
 {
 	const char * exec_name = strrchr(shell,'/');
-	if (exec_name)
-		exec_name++;
-	else
-		exec_name = shell;
+	if (exec_name) exec_name++;
+	else exec_name = shell;
 
 	snprintf(toybuf,sizeof(toybuf)-1, "-%s", shell);
 	execl(shell, toybuf, NULL);
@@ -174,20 +147,18 @@
 
 void setup_environment(const struct passwd *pwd, int clear_env)
 {
-	if (chdir(pwd->pw_dir))
-		printf("can't chdir to home directory: %s\n", pwd->pw_dir);
+	if (chdir(pwd->pw_dir)) printf("bad home dir: %s\n", pwd->pw_dir);
 
-	if (clear_env)
-	{
+	if (clear_env) {
 		const char * term = getenv("TERM");
 		clearenv();
 		if (term) setenv("TERM", term, 1);
 	}
 
-	setenv("USER",	pwd->pw_name,  1);
-	setenv("LOGNAME", pwd->pw_name,  1);
-	setenv("HOME",	pwd->pw_dir,   1);
-	setenv("SHELL",   pwd->pw_shell, 1);
+	setenv("USER", pwd->pw_name, 1);
+	setenv("LOGNAME", pwd->pw_name, 1);
+	setenv("HOME", pwd->pw_dir, 1);
+	setenv("SHELL", pwd->pw_shell, 1);
 }
 
 void login_main(void)
@@ -195,25 +166,23 @@
 	int f_flag = (toys.optflags & 4) >> 2;
 	int p_flag = (toys.optflags & 2) >> 1;
 	int h_flag = toys.optflags & 1;
-	char username[USER_NAME_MAX_SIZE+1];
+	char username[USER_NAME_MAX_SIZE+1], *pass = NULL, **ss;
 	struct passwd * pwd = NULL;
 	struct spwd * spwd = NULL;
-	char *pass = NULL;
 	int auth_fail_cnt = 0;
 
 	if (f_flag && toys.optc != 1)
 		error_exit("-f requires username");
 
-	if (geteuid() != 0 )
-		error_exit("Cannot possibly work without effective root");
+	if (geteuid()) error_exit("not root");
 
-	if (!isatty(0) || !isatty(1) || !isatty(2))
-		error_exit("Not connected to a tty");
+	if (!isatty(0) || !isatty(1) || !isatty(2)) error_exit("no tty");
 
 	openlog("login", LOG_PID | LOG_CONS, LOG_AUTH);
 	signal(SIGALRM, login_timeout_handler);
 	alarm(LOGIN_TIMEOUT);
-	sanitize_env();
+
+	for (ss = forbid; *ss; ss++) unsetenv(*ss);
 
 	while (1) {
 		tcflush(0, TCIFLUSH);
@@ -223,47 +192,37 @@
 			strncpy(username, toys.optargs[0], USER_NAME_MAX_SIZE);
 		else {
 			read_user(username, USER_NAME_MAX_SIZE+1);
-			if (username[0] == 0)
-				continue;
+			if (username[0] == 0) continue;
 		}
 
 		pwd = getpwnam(username);
-		if (!pwd)
-			goto query_pass; // Non-existing user
+		if (!pwd) goto query_pass; // Non-existing user
 
 		if (pwd->pw_passwd[0] == '!' || pwd->pw_passwd[0] == '*')
 			goto query_pass;  // Locked account
 
-		if (f_flag)
-			break; // Pre-authenticated
+		if (f_flag) break; // Pre-authenticated
 
-		if (pwd->pw_passwd[0] == '\0')
-			break; // Password-less account
+		if (!pwd->pw_passwd[0]) break; // Password-less account
 
 		pass = pwd->pw_passwd;
 		if (pwd->pw_passwd[0] == 'x') {
 			spwd = getspnam (username);
-			if (spwd)
-				pass = spwd->sp_pwdp;
+			if (spwd) pass = spwd->sp_pwdp;
 		}
 
-	query_pass:
-		if (!verify_password(pass))
-			break;
+query_pass:
+		if (!verify_password(pass)) break;
 
 		f_flag = 0;
 		syslog(LOG_WARNING, "invalid password for '%s' on %s %s %s", username,
-			ttyname(0),
-			(h_flag)?"from":"",
-			(h_flag)?TT.hostname:"");
+			ttyname(0), (h_flag)?"from":"", (h_flag)?TT.hostname:"");
 
 		sleep(LOGIN_FAIL_TIMEOUT);
 		puts("Login incorrect");
 
 		if (++auth_fail_cnt == 3)
-		{
 			error_exit("Maximum number of tries exceeded (%d)\n", auth_fail_cnt);
-		}
 
 		username[0] = 0;
 		pwd = NULL;
@@ -272,20 +231,16 @@
 
 	alarm(0);
 
-	if (pwd->pw_uid)
-		handle_nologin();
+	if (pwd->pw_uid) handle_nologin();
 
-	if (change_identity(pwd))
-		error_exit("Failed to change identity");
+	if (change_identity(pwd)) error_exit("Failed to change identity");
 
 	setup_environment(pwd, !p_flag);
 
 	handle_motd();
 
 	syslog(LOG_INFO, "%s logged in on %s %s %s", pwd->pw_name,
-		ttyname(0),
-		(h_flag)?"from":"",
-		(h_flag)?TT.hostname:"");
+		ttyname(0), (h_flag)?"from":"", (h_flag)?TT.hostname:"");
 
 	spawn_shell(pwd->pw_shell);
 }