From a6f8cbf6e732d16b5f40e6eed7ee7fa8f4c307ba Mon Sep 17 00:00:00 2001
From: Alex Kotov <kotovalexarian@gmail.com>
Date: Thu, 13 Jan 2022 19:41:50 +0500
Subject: [PATCH] Write code

---
 src/multiboot2/header_is_valid.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/src/multiboot2/header_is_valid.c b/src/multiboot2/header_is_valid.c
index a5a4fb2..3f7f14d 100644
--- a/src/multiboot2/header_is_valid.c
+++ b/src/multiboot2/header_is_valid.c
@@ -11,6 +11,14 @@
 bool KernAux_Multiboot2_Header_is_valid(
     const struct KernAux_Multiboot2_Header *const multiboot2_header
 ) {
+    if (multiboot2_header->magic != KERNAUX_MULTIBOOT2_MAGIC) return false;
+
+    if (multiboot2_header->arch != KERNAUX_MULTIBOOT2_ARCH_I386 &&
+        multiboot2_header->arch != KERNAUX_MULTIBOOT2_ARCH_MIPS32)
+    {
+        return false;
+    }
+
     if (multiboot2_header->total_size <
         sizeof(struct KernAux_Multiboot2_Header) +
         sizeof(struct KernAux_Multiboot2_HTag_None))
@@ -18,6 +26,15 @@ bool KernAux_Multiboot2_Header_is_valid(
         return false;
     }
 
+    if (multiboot2_header->checksum !=
+        KERNAUX_MULTIBOOT2_CHECKSUM(
+            multiboot2_header->arch,
+            multiboot2_header->total_size
+        )
+    ) {
+        return false;
+    }
+
     const struct KernAux_Multiboot2_HTagBase *tag_base =
         (struct KernAux_Multiboot2_HTagBase*)
         KERNAUX_MULTIBOOT2_DATA(multiboot2_header);