1 files changed, 123 insertions, 0 deletions
diff --git a/webauth.c b/webauth.c
new file mode 100644
index 0000000..f4e5148
--- /dev/null
+++ b/webauth.c
@@ -0,0 +1,123 @@
+/*
+ * webauth.c
+ *
+ * See the README file for copyright information and how to reach the author.
+ *
+ */
+
+// https://gnunet.org/svn/libmicrohttpd/doc/examples/tlsauthentication.c
+
+#include "httpd.h"
+
+//***************************************************************************
+// String 2 Base 64
+//***************************************************************************
+
+char* string2base64(const char* message)
+{
+   const char *lookup = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+   unsigned long l;
+   uint i;
+   char* tmp;
+   size_t length = strlen(message);
+
+   tmp = (char*)malloc(length * 2);
+
+   if (!tmp)
+      return tmp;
+
+   tmp[0] = 0;
+
+   for (i = 0; i < length; i += 3)
+   {
+      l = (((unsigned long) message[i]) << 16)
+         | (((i + 1) < length) ? (((unsigned long) message[i + 1]) << 8) : 0)
+         | (((i + 2) < length) ? ((unsigned long) message[i + 2]) : 0);
+
+      strncat (tmp, &lookup[(l >> 18) & 0x3F], 1);
+      strncat (tmp, &lookup[(l >> 12) & 0x3F], 1);
+
+      if (i + 1 < length)
+         strncat(tmp, &lookup[(l >> 6) & 0x3F], 1);
+      if (i + 2 < length)
+         strncat(tmp, &lookup[l & 0x3F], 1);
+   }
+
+   if (length % 3)
+      strncat(tmp, "===", 3 - length % 3);
+
+   return tmp;
+}
+
+//***************************************************************************
+// Ask For Authentication
+//***************************************************************************
+
+int cEpgHttpd::askForAuthentication(struct MHD_Connection* connection, const char* realm)
+{
+   int status;
+   struct MHD_Response* response;
+   char* headervalue = 0;
+
+   response = MHD_create_response_from_buffer(0, 0, MHD_RESPMEM_PERSISTENT);
+
+   if (!response)
+      return MHD_NO;
+
+   asprintf(&headervalue, "Basic realm=\"%s\"", realm);
+   status = MHD_add_response_header(response, "WWW-Authenticate", headervalue);
+   free(headervalue);
+
+   if (!status)
+   {
+      MHD_destroy_response(response);
+      return MHD_NO;
+   }
+
+   status = MHD_queue_response(connection, MHD_HTTP_UNAUTHORIZED, response);
+
+   MHD_destroy_response(response);
+
+   return status;
+}
+
+//***************************************************************************
+// Is Authenticated
+//***************************************************************************
+
+int cEpgHttpd::isAuthenticated(struct MHD_Connection* connection,
+                               const char* username, const char* password)
+{
+   const char *headervalue;
+   char *expected64, *expected;
+   const char *strbase = "Basic ";
+   int authenticated;
+
+   headervalue = MHD_lookup_connection_value(connection, MHD_HEADER_KIND, "Authorization");
+
+   if (!headervalue)
+      return 0;
+
+   if (strncmp(headervalue, strbase, strlen(strbase)) != 0)
+      return 0;
+
+   expected = (char*)malloc(strlen(username) + 1 + strlen(password) + 1);
+
+   if (!expected)
+      return 0;
+
+   strcpy(expected, username);
+   strcat(expected, ":");
+   strcat(expected, password);
+
+   expected64 = string2base64(expected);
+   free(expected);
+
+   if (!expected64)
+      return 0;
+
+   authenticated = (strcmp(headervalue + strlen(strbase), expected64) == 0);
+   free(expected64);
+
+   return authenticated;
+}