Changes in boot/generic/src/gzip.c [b169619:63a045c] in mainline

File:

• boot/generic/src/gzip.c (modified) (5 diffs)

boot/generic/src/gzip.c

@@ -32 +32 @@
 #include <stddef.h>
 #include <errno.h>
-#include <mem.h>
+#include <memstr.h>
 #include <byteorder.h>
 #include <gzip.h>
@@ -63 +63 @@
 } __attribute__((packed)) gzip_footer_t;
 
-/** Check GZIP signature
- *
- * Checks whether the source buffer start with a GZIP signature.
- *
- * @param[in] src    Source data buffer.
- * @param[in] srclen Source buffer size (bytes).
- *
- * @return True if GZIP signature found.
- * @return False if no GZIP signature found.
- *
- */
-bool gzip_check(const void *src, size_t srclen)
+size_t gzip_size(const void *src, size_t srclen)
 {
-        if ((srclen < (sizeof(gzip_header_t) + sizeof(gzip_footer_t))))
-                return false;
+        gzip_header_t header;
+        gzip_footer_t footer;
 
-        gzip_header_t header;
+        if ((srclen < sizeof(header)) || (srclen < sizeof(footer)))
+                return 0;
+
         memcpy(&header, src, sizeof(header));
+        memcpy(&footer, src + srclen - sizeof(footer), sizeof(footer));
 
         if ((header.id1 != GZIP_ID1) ||
@@ -86 +78 @@
             (header.method != GZIP_METHOD_DEFLATE) ||
             ((header.flags & (~GZIP_FLAGS_MASK)) != 0))
-                return false;
-
-        return true;
-}
-
-/** Get uncompressed size
- *
- * Note that the uncompressed size is read from the GZIP footer
- * (and not calculated by acutally decompressing the GZip archive).
- * Thus the source of the GZip archive needs to be trusted.
- *
- * @param[in]  src    Source data buffer.
- * @param[out] srclen Source buffer size (bytes).
- *
- * @return Uncompressed size.
- *
- */
-size_t gzip_size(const void *src, size_t srclen)
-{
-        if (!gzip_check(src, srclen))
                 return 0;
-
-        gzip_footer_t footer;
-        memcpy(&footer, src + srclen - sizeof(footer), sizeof(footer));
 
         return uint32_t_le2host(footer.size);
@@ -116 +85 @@
 /** Expand GZIP compressed data
  *
- * The routine compares the output buffer size with
- * the size encoded in the input stream. This
+ * The routine allocates the output buffer based
+ * on the size encoded in the input stream. This
  * effectively limits the size of the uncompressed
  * data to 4 GiB (expanding input streams that actually
@@ -139 +108 @@
 int gzip_expand(const void *src, size_t srclen, void *dest, size_t destlen)
 {
-        if (!gzip_check(src, srclen))
+        gzip_header_t header;
+        gzip_footer_t footer;
+
+        if ((srclen < sizeof(header)) || (srclen < sizeof(footer)))
                 return EINVAL;
 
         /* Decode header and footer */
 
-        gzip_header_t header;
         memcpy(&header, src, sizeof(header));
+        memcpy(&footer, src + srclen - sizeof(footer), sizeof(footer));
 
-        gzip_footer_t footer;
-        memcpy(&footer, src + srclen - sizeof(footer), sizeof(footer));
+        if ((header.id1 != GZIP_ID1) ||
+            (header.id2 != GZIP_ID2) ||
+            (header.method != GZIP_METHOD_DEFLATE) ||
+            ((header.flags & (~GZIP_FLAGS_MASK)) != 0))
+                return EINVAL;
 
         if (destlen != uint32_t_le2host(footer.size))