added su

src/findutils/xargs/xargs.c

@@ -8,6 +8,10 @@
 #include <limits.h>
 #include <ctype.h>
 
+#ifndef ARG_MAX
+#define ARG_MAX 10000
+#endif
+
 int args;
 char *cmd[ARG_MAX + 1];
 

src/loginutils/cryptpw/build.sh

@@ -1,3 +1,3 @@
 #!/bin/sh
 project_dir=$(pwd)
-echo ./*.c $CFLAGS -o $OUTPUT$(basename $project_dir) | xargs $CC
+echo ./*.c $CFLAGS -o $OUTPUT$(basename $project_dir) | xargs $CC -lcrypt

src/loginutils/login/build.sh

@@ -1,3 +1,3 @@
 #!/bin/sh
 project_dir=$(pwd)
-echo ./*.c $CFLAGS -o $OUTPUT$(basename $project_dir) | xargs $CC
+echo ./*.c $CFLAGS -o $OUTPUT$(basename $project_dir) | xargs $CC -lcrypt

src/loginutils/su/build.sh

@@ -0,0 +1,3 @@
+#!/bin/sh
+project_dir=$(pwd)
+echo ./*.c $CFLAGS -o $OUTPUT$(basename $project_dir) | xargs $CC -lcrypt

src/loginutils/su/su.c

@@ -0,0 +1,146 @@
+#include <pwd.h>
+#include <stdio.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <limits.h>
+#include <unistd.h>
+#include <signal.h>
+#include <termios.h>
+#include "pw_check.h"
+#include "unused.h"
+
+#define ECHOFLAGS (ECHO | ECHOE | ECHOK | ECHONL)
+
+char *c_flag = NULL;
+char *s_flag = NULL;
+char p_flag;
+
+int hide_input(int fd, int flag) {
+	struct termios term;
+	if (tcgetattr(fd, &term) < 0)
+		return 1;
+
+	if (flag)
+		term.c_lflag &= ~ECHOFLAGS;
+
+	else
+		term.c_lflag |= ECHOFLAGS;
+
+	if (tcsetattr(fd, TCSAFLUSH, &term) < 0)
+		return 1;
+
+	return 0;
+}
+
+void su(const struct passwd *pw) {
+	char *shell = s_flag;
+	if (s_flag == NULL)
+		shell = (pw->pw_shell[0] == '\0') ? "/bin/sh" : pw->pw_shell;
+
+	if (!p_flag) {
+		setenv("HOME", pw->pw_dir, 1);
+		setenv("SHELL", shell, 1);
+		setenv("USER", pw->pw_name, 1);
+		setenv("LOGNAME", pw->pw_name, 1);
+		setenv("PATH", "/bin", 1);
+	}
+
+	if (c_flag)
+		execlp(shell, shell, "-c", c_flag, NULL);
+
+	else
+		execlp(shell, shell, "-l", NULL);
+}
+
+int password(const struct passwd *pw) {
+	static char psswd[512];
+
+	printf("Password: ");
+	fflush(stdout);
+
+	if (hide_input(STDIN_FILENO, 1)) {
+		fprintf(stderr, "su: %s\n", strerror(errno));
+		return 1;
+	}
+
+	off_t ret = 0;
+	if ((ret = read(STDIN_FILENO, psswd, sizeof(psswd))) <= 0) {
+		fprintf(stderr, "su: %s\n", strerror(errno));
+		return 1;
+	}
+
+	psswd[ret - 1] = '\0';
+	if (pw_check("su", pw, psswd)) {
+		memset(psswd, '\0', sizeof(psswd));
+		return 1;
+	}
+
+	printf("\n");
+	memset(psswd, '\0', sizeof(psswd));
+	return 0;
+}
+
+void endwin(int sig) {
+	UNUSED(sig);
+
+	hide_input(STDIN_FILENO, 0);
+	exit(1);
+}
+
+int main(int argc, char **argv) {
+	int opt;
+	while ((opt = getopt(argc, argv, "c:s:p")) != -1) {
+		switch (opt) {
+			case 'c':
+				c_flag = optarg;
+				break;
+
+			case 's':
+				s_flag = optarg;
+				break;
+
+			case 'p':
+				p_flag = 1;
+				break;
+
+			default:
+				printf("su [cps] [user Default: root]\n\t-c CMD Command to pass to \'sh -c\'\n\t-s SHELL Shell to use instead of user's default\n\t-p Do not set new env\n");
+				return 0;
+		}
+	}
+
+	argc -= optind;
+	argv += optind;
+
+	char *user = "root";
+	if (argv[0])
+		user = argv[0];
+
+	struct passwd *pw = getpwnam(user);
+	if (!pw) {
+		fprintf(stderr, "su: Incorrent username\n");
+		return 1;
+	}
+
+	signal(SIGINT, endwin);
+
+	int ret = password(pw);
+	hide_input(STDIN_FILENO, 0);
+	if (ret)
+		return 1;
+
+	/* Start */
+	if (setgid(pw->pw_gid) < 0) {
+		fprintf(stderr, "su: %s\n", strerror(errno));
+		return 1;
+	}
+
+	if (setuid(pw->pw_uid) < 0) {
+		fprintf(stderr, "su: %s\n", strerror(errno));
+		return 1;
+	}
+
+	su(pw);
+	return 0;
+}