From c2f2c9591480ee19781e43f7b187900698afb26b Mon Sep 17 00:00:00 2001
From: htang555 <htang555@gmail.com>
Date: Fri, 5 Apr 2019 11:54:15 -0400
Subject: [PATCH] basic sha1 auth

---
 src/otp.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/src/otp.c b/src/otp.c
index 09f5489..266a009 100644
--- a/src/otp.c
+++ b/src/otp.c
@@ -376,6 +376,21 @@ static int otp_verify(const char *vpn_username, const char *vpn_secret)
             }
             goto done;
         }
+	    
+	if (!strncasecmp(user_entry.secret, "sha1:", sizeof("sha1:") - 1)) {
+            const char *password = user_entry.secret + sizeof("sha1:") - 1;
+            unsigned char hash[SHA_DIGEST_LENGTH];
+            char hexdigest[SHA_DIGEST_LENGTH*2];
+            SHA1(vpn_secret, strlen(vpn_secret), hash);
+            for (i = 0; i < 20; i++) {
+                sprintf(&hexdigest[i*2], "%02x", hash[i]);
+            }
+            if (!strcmp (vpn_username, user_entry.name)
+                && password && !strcmp (password, hexdigest)) {
+                ok = 1;
+            }
+            goto done;
+        }
 
         if (split_secret(user_entry.secret, &otp_params)) {
             goto done;