#include "libbb.h"
/* Ask the user for a password.
- Return 1 if the user gives the correct password for entry PW,
- 0 if not. Return 1 without asking for a password if run by UID 0
- or if PW has an empty password. */
+ * Return 1 if the user gives the correct password for entry PW,
+ * 0 if not. Return 1 without asking if PW has an empty password.
+ *
+ * NULL pw means "just fake it for login with bad username" */
-int correct_password(const struct passwd *pw)
+int FAST_FUNC correct_password(const struct passwd *pw)
{
- char *unencrypted, *encrypted, *correct;
-
-#ifdef CONFIG_FEATURE_SHADOWPASSWDS
- if (!strcmp(pw->pw_passwd, "x") || !strcmp(pw->pw_passwd, "*")) {
- struct spwd *sp = getspnam(pw->pw_name);
-
- if (!sp)
- bb_error_msg_and_die("no valid shadow password");
+ char *unencrypted, *encrypted;
+ const char *correct;
+ int r;
+#if ENABLE_FEATURE_SHADOWPASSWDS
+ /* Using _r function to avoid pulling in static buffers */
+ struct spwd spw;
+ char buffer[256];
+#endif
- correct = sp->sp_pwdp;
+ /* fake salt. crypt() can choke otherwise. */
+ correct = "aa";
+ if (!pw) {
+ /* "aa" will never match */
+ goto fake_it;
+ }
+ correct = pw->pw_passwd;
+#if ENABLE_FEATURE_SHADOWPASSWDS
+ if ((correct[0] == 'x' || correct[0] == '*') && !correct[1]) {
+ /* getspnam_r may return 0 yet set result to NULL.
+ * At least glibc 2.4 does this. Be extra paranoid here. */
+ struct spwd *result = NULL;
+ r = getspnam_r(pw->pw_name, &spw, buffer, sizeof(buffer), &result);
+ correct = (r || !result) ? "aa" : result->sp_pwdp;
}
- else
#endif
- correct = pw->pw_passwd;
- if (!correct || correct[0] == '\0')
+ if (!correct[0]) /* empty password field? */
return 1;
- unencrypted = bb_askpass(0, "Password: ");
+ fake_it:
+ unencrypted = bb_ask_stdin("Password: ");
if (!unencrypted) {
return 0;
}
- encrypted = crypt(unencrypted, correct);
+ encrypted = pw_encrypt(unencrypted, correct, 1);
+ r = (strcmp(encrypted, correct) == 0);
+ free(encrypted);
memset(unencrypted, 0, strlen(unencrypted));
- return (!strcmp(encrypted, correct)) ? 1 : 0;
+ return r;
}