1 files changed, 92 insertions, 0 deletions
diff --git a/checkpasswd/checkpassword.c b/checkpasswd/checkpassword.c
new file mode 100644
index 0000000..afca798
--- /dev/null
+++ b/checkpasswd/checkpassword.c
@@ -0,0 +1,92 @@
+#include "error.h"
+#include "pathexec.h"
+#include "prot.h"
+
+extern char *crypt();
+#include <pwd.h>
+static struct passwd *pw;
+
+#include "hasspnam.h"
+#ifdef HASGETSPNAM
+#include <shadow.h>
+static struct spwd *spw;
+#endif
+
+#include "hasuserpw.h"
+#ifdef HASUSERPW
+#include <userpw.h>
+static struct userpw *upw;
+#endif
+
+static char up[513];
+static int uplen;
+
+main(int argc,char **argv)
+{
+  char *login;
+  char *password;
+  char *encrypted;
+  char *stored;
+  int r;
+  int i;
+ 
+  if (!argv[1]) _exit(2);
+ 
+  uplen = 0;
+  for (;;) {
+    do
+      r = read(3,up + uplen,sizeof(up) - uplen);
+    while ((r == -1) && (errno == error_intr));
+    if (r == -1) _exit(111);
+    if (r == 0) break;
+    uplen += r;
+    if (uplen >= sizeof(up)) _exit(1);
+  }
+  close(3);
+
+  i = 0;
+  if (i >= uplen) _exit(2);
+  login = up + i;
+  while (up[i++]) if (i >= uplen) _exit(2);
+  password = up + i;
+  if (i >= uplen) _exit(2);
+  while (up[i++]) if (i >= uplen) _exit(2);
+
+  pw = getpwnam(login);
+  if (pw)
+    stored = pw->pw_passwd;
+  else {
+    if (errno == error_txtbsy) _exit(111);
+    _exit(1);
+  }
+#ifdef HASUSERPW
+  upw = getuserpw(login);
+  if (upw)
+    stored = upw->upw_passwd;
+  else
+    if (errno == error_txtbsy) _exit(111);
+#endif
+#ifdef HASGETSPNAM
+  spw = getspnam(login);
+  if (spw)
+    stored = spw->sp_pwdp;
+  else
+    if (errno == error_txtbsy) _exit(111);
+#endif
+  if (!stored) _exit(1);
+ 
+  encrypted = crypt(password,stored);
+  for (i = 0;i < sizeof(up);++i) up[i] = 0;
+ 
+  if (!*stored || strcmp(encrypted,stored)) _exit(1);
+ 
+  if (prot_gid((int) pw->pw_gid) == -1) _exit(1);
+  if (prot_uid((int) pw->pw_uid) == -1) _exit(1);
+  if (chdir(pw->pw_dir) == -1) _exit(111);
+
+  if (!pathexec_env("USER",pw->pw_name)) _exit(111);
+  if (!pathexec_env("HOME",pw->pw_dir)) _exit(111);
+  if (!pathexec_env("SHELL",pw->pw_shell)) _exit(111);
+  pathexec(argv + 1);
+  _exit(111);
+}