Changeset 3621 in MondoRescue for branches/3.3/mindi-busybox/libbb/correct_password.c

Timestamp:

Dec 20, 2016, 4:07:32 PM (7 years ago)

Author:

Bruno Cornec

Message:

New 3?3 banch for incorporation of latest busybox 1.25. Changing minor version to handle potential incompatibilities.

Location:

branches/3.3

Files:

• . (copied) (copied from branches/3.2 )
• mindi-busybox/libbb/correct_password.c (modified) (1 diff)

branches/3.3/mindi-busybox/libbb/correct_password.c

@@ -31 +31 @@
 #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 if PW has an empty password.
- *
- * NULL pw means "just fake it for login with bad username" */
+#define SHADOW_BUFSIZE 256
 
-int FAST_FUNC correct_password(const struct passwd *pw)
+/* Retrieve encrypted password string for pw.
+ * If pw == NULL, return a string which fails password check against any
+ * password.
+ */
+#if !ENABLE_FEATURE_SHADOWPASSWDS
+#define get_passwd(pw, buffer) get_passwd(pw)
+#endif
+static const char *get_passwd(const struct passwd *pw, char buffer[SHADOW_BUFSIZE])
 {
-    char *unencrypted, *encrypted;
-    const char *correct;
-    int r;
-    /* fake salt. crypt() can choke otherwise. */
-    correct = "aa";
-    if (!pw) {
-        /* "aa" will never match */
-        goto fake_it;
-    }
-    correct = pw->pw_passwd;
+    const char *pass;
+
+    if (!pw)
+        return "aa"; /* "aa" will never match */
+
+    pass = pw->pw_passwd;
 #if ENABLE_FEATURE_SHADOWPASSWDS
     /* Using _r function to avoid pulling in static buffers */
-    if ((correct[0] == 'x' || correct[0] == '*') && !correct[1]) {
+    if ((pass[0] == 'x' || pass[0] == '*') && !pass[1]) {
         struct spwd spw;
-        char buffer[256];
+        int r;
         /* 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;
+        r = getspnam_r(pw->pw_name, &spw, buffer, SHADOW_BUFSIZE, &result);
+        pass = (r || !result) ? "aa" : result->sp_pwdp;
     }
 #endif
+    return pass;
+}
 
-    if (!correct[0]) /* empty password field? */
+/*
+ * Return 1 if PW has an empty password.
+ * Return 1 if the user gives the correct password for entry PW,
+ * 0 if not.
+ * NULL pw means "just fake it for login with bad username"
+ */
+int FAST_FUNC check_password(const struct passwd *pw, const char *plaintext)
+{
+    IF_FEATURE_SHADOWPASSWDS(char buffer[SHADOW_BUFSIZE];)
+    char *encrypted;
+    const char *pw_pass;
+    int r;
+
+    pw_pass = get_passwd(pw, buffer);
+    if (!pw_pass[0]) { /* empty password field? */
+        return 1;
+    }
+
+    encrypted = pw_encrypt(plaintext, /*salt:*/ pw_pass, 1);
+    r = (strcmp(encrypted, pw_pass) == 0);
+    free(encrypted);
+    return r;
+}
+
+
+/* Ask the user for a password.
+ * Return 1 without asking if PW has an empty password.
+ * Return -1 on EOF, error while reading input, or timeout.
+ * Return 1 if the user gives the correct password for entry PW,
+ * 0 if not.
+ *
+ * NULL pw means "just fake it for login with bad username"
+ */
+int FAST_FUNC ask_and_check_password_extended(const struct passwd *pw,
+        int timeout, const char *prompt)
+{
+    IF_FEATURE_SHADOWPASSWDS(char buffer[SHADOW_BUFSIZE];)
+    char *plaintext;
+    const char *pw_pass;
+    int r;
+
+    pw_pass = get_passwd(pw, buffer);
+    if (!pw_pass[0]) /* empty password field? */
         return 1;
 
- fake_it:
-    unencrypted = bb_ask_stdin("Password: ");
-    if (!unencrypted) {
-        return 0;
+    plaintext = bb_ask(STDIN_FILENO, timeout, prompt);
+    if (!plaintext) {
+        /* EOF (such as ^D) or error (such as ^C) or timeout */
+        return -1;
     }
-    encrypted = pw_encrypt(unencrypted, correct, 1);
-    r = (strcmp(encrypted, correct) == 0);
-    free(encrypted);
-    memset(unencrypted, 0, strlen(unencrypted));
+
+    r = check_password(pw, plaintext);
+    nuke_str(plaintext);
     return r;
 }
+
+int FAST_FUNC ask_and_check_password(const struct passwd *pw)
+{
+    return ask_and_check_password_extended(pw, 0, "Password: ");
+}