1 files changed, 99 insertions, 0 deletions
diff --git a/tools/src/tinf/tinfzlib.c b/tools/src/tinf/tinfzlib.c
new file mode 100644
index 0000000..6af07b8
--- /dev/null
+++ b/tools/src/tinf/tinfzlib.c
@@ -0,0 +1,99 @@
+/*
+ * tinfzlib - tiny zlib decompressor
+ *
+ * This version of tinfzlib was modified for use with m1n1.
+ *
+ * Copyright (c) 2003-2019 Joergen Ibsen
+ *
+ * This software is provided 'as-is', without any express or implied
+ * warranty. In no event will the authors be held liable for any damages
+ * arising from the use of this software.
+ *
+ * Permission is granted to anyone to use this software for any purpose,
+ * including commercial applications, and to alter it and redistribute it
+ * freely, subject to the following restrictions:
+ *
+ *   1. The origin of this software must not be misrepresented; you must
+ *      not claim that you wrote the original software. If you use this
+ *      software in a product, an acknowledgment in the product
+ *      documentation would be appreciated but is not required.
+ *
+ *   2. Altered source versions must be plainly marked as such, and must
+ *      not be misrepresented as being the original software.
+ *
+ *   3. This notice may not be removed or altered from any source
+ *      distribution.
+ */
+
+#include "tinf.h"
+
+static unsigned int read_be32(const unsigned char *p)
+{
+	return ((unsigned int) p[0] << 24)
+	     | ((unsigned int) p[1] << 16)
+	     | ((unsigned int) p[2] << 8)
+	     | ((unsigned int) p[3]);
+}
+
+int tinf_zlib_uncompress(void *dest, unsigned int *destLen,
+                         const void *source, unsigned int *sourceLen)
+{
+	const unsigned char *src = (const unsigned char *) source;
+	unsigned char *dst = (unsigned char *) dest;
+	unsigned int a32;
+	int res;
+	unsigned char cmf, flg;
+	unsigned int sourceDataLen = sourceLen ? *sourceLen - 6 : 0;
+
+	/* -- Check header -- */
+
+	/* Check room for at least 2 byte header and 4 byte trailer */
+	if (*sourceLen && *sourceLen < 6) {
+		return TINF_DATA_ERROR;
+	}
+
+	/* Get header bytes */
+	cmf = src[0];
+	flg = src[1];
+
+	/* Check checksum */
+	if ((256 * cmf + flg) % 31) {
+		return TINF_DATA_ERROR;
+	}
+
+	/* Check method is deflate */
+	if ((cmf & 0x0F) != 8) {
+		return TINF_DATA_ERROR;
+	}
+
+	/* Check window size is valid */
+	if ((cmf >> 4) > 7) {
+		return TINF_DATA_ERROR;
+	}
+
+	/* Check there is no preset dictionary */
+	if (flg & 0x20) {
+		return TINF_DATA_ERROR;
+	}
+
+	/* -- Decompress data -- */
+
+	res = tinf_uncompress(dst, destLen, src + 2, &sourceDataLen);
+
+	if (res != TINF_OK) {
+		return TINF_DATA_ERROR;
+	}
+
+	/* -- Check Adler-32 checksum -- */
+
+	a32 = read_be32(&src[sourceDataLen + 2]);
+
+	if (a32 != tinf_adler32(dst, *destLen)) {
+		return TINF_DATA_ERROR;
+	}
+
+	if (sourceLen)
+		*sourceLen = sourceDataLen + 6;
+
+	return TINF_OK;
+}