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/* See LICENSE file for license details. */
#define _XOPEN_SOURCE 700
#include <unistd.h>
#include <pwd.h>
#include <grp.h>
#include <shadow.h>
#include <crypt.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <stdarg.h>
#include <termios.h>
#include <sys/wait.h>
#include "../accent.h"
#include "config.h"
static ColorShm *accentshm;
static char accentcol[8] = "#005577";
static void
die(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
vfprintf(stderr, fmt, ap);
va_end(ap);
exit(1);
}
static void
updateaccent(void)
{
if (!readaccent(&accentshm, accentcol))
memcpy(accentcol, "#005577", 8);
}
static void
parseaccent(int *r, int *g, int *b)
{
unsigned int ri, gi, bi;
if (sscanf(accentcol + 1, "%02x%02x%02x", &ri, &gi, &bi) == 3) {
*r = ri;
*g = gi;
*b = bi;
} else {
*r = 0x00;
*g = 0x55;
*b = 0x77;
}
}
static void
colored(const char *msg)
{
int r, g, b;
parseaccent(&r, &g, &b);
printf("\033[38;2;%d;%d;%dm%s\033[0m", r, g, b, msg);
}
static const char *
gethash(const char *user)
{
struct passwd *pw;
const char *hash;
if (!(pw = getpwnam(user)))
return NULL;
hash = pw->pw_passwd;
#if HAVE_SHADOW_H
if (!strcmp(hash, "x")) {
struct spwd *sp;
if (!(sp = getspnam(user)))
return NULL;
hash = sp->sp_pwdp;
}
#endif
return hash;
}
static int
auth(const char *user, const char *pass)
{
const char *hash = gethash(user);
char *cryptpw;
if (!hash)
return 0;
if (!(cryptpw = crypt(pass, hash)))
return 0;
return !strcmp(cryptpw, hash);
}
static void
readinput(char *buf, size_t len)
{
if (!fgets(buf, len, stdin))
buf[0] = '\0';
buf[strcspn(buf, "\n")] = '\0';
}
static void
readpass(char *buf, size_t len)
{
struct termios old, new;
tcgetattr(STDIN_FILENO, &old);
new = old;
new.c_lflag &= ~(ECHO);
tcsetattr(STDIN_FILENO, TCSAFLUSH, &new);
readinput(buf, len);
tcsetattr(STDIN_FILENO, TCSAFLUSH, &old);
}
static void
runsession(const char *user)
{
struct passwd *pw;
pid_t pid;
if (!(pw = getpwnam(user)))
return;
if ((pid = fork()) == 0) {
if (initgroups(user, pw->pw_gid) < 0)
die("slogin: initgroups failed\n");
if (setgid(pw->pw_gid) < 0)
die("slogin: setgid failed\n");
if (setuid(pw->pw_uid) < 0)
die("slogin: setuid failed\n");
setenv("HOME", pw->pw_dir, 1);
if (chdir(pw->pw_dir) < 0)
die("slogin: chdir failed\n");
execvp(logincmd[0], (char *const *)logincmd);
_exit(1);
}
waitpid(pid, NULL, 0);
}
int
main(void)
{
char user[64];
char pass[64];
for (;;) {
updateaccent();
printf("\033[2J\033[H");
colored("login: ");
fflush(stdout);
readinput(user, sizeof user);
colored("password: ");
fflush(stdout);
readpass(pass, sizeof pass);
printf("\n");
if (auth(user, pass)) {
memset(pass, 0, sizeof pass);
runsession(user);
} else {
colored("Login incorrect\n");
memset(pass, 0, sizeof pass);
sleep(2);
}
}
return 0;
}
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