From 99fb66fed6fb9b30a119962510bbe8ac666b6215 Mon Sep 17 00:00:00 2001
From: jsing <jsing@openbsd.org>
Date: Thu, 10 Aug 2023 13:54:21 +0000
Subject: [PATCH] Implement MD5_{Update,Transform,Final}() directly in md5.c.

Copy the update, transform and final functions from md32_common.h, manually
expanding the macros for MD5. This will allow for further clean up to
occur.

No change in generated assembly.
---
 lib/libcrypto/md5/md5.c | 104 +++++++++++++++++++++++++++++++++++++++-
 1 file changed, 103 insertions(+), 1 deletion(-)

diff --git a/lib/libcrypto/md5/md5.c b/lib/libcrypto/md5/md5.c
index 7f6535506c3..5169627c02e 100644
--- a/lib/libcrypto/md5/md5.c
+++ b/lib/libcrypto/md5/md5.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: md5.c,v 1.8 2023/08/10 13:41:18 jsing Exp $ */
+/* $OpenBSD: md5.c,v 1.9 2023/08/10 13:54:21 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -96,7 +96,109 @@ __END_HIDDEN_DECLS
 	} while (0)
 #define	HASH_BLOCK_DATA_ORDER	md5_block_data_order
 
+#define HASH_NO_UPDATE
+#define HASH_NO_TRANSFORM
+#define HASH_NO_FINAL
+
 #include "md32_common.h"
+
+int
+MD5_Update(MD5_CTX *c, const void *data_, size_t len)
+{
+	const unsigned char *data = data_;
+	unsigned char *p;
+	MD5_LONG l;
+	size_t n;
+
+	if (len == 0)
+		return 1;
+
+	l = (c->Nl + (((MD5_LONG)len) << 3))&0xffffffffUL;
+	/* 95-05-24 eay Fixed a bug with the overflow handling, thanks to
+	 * Wei Dai <weidai@eskimo.com> for pointing it out. */
+	if (l < c->Nl) /* overflow */
+		c->Nh++;
+	c->Nh+=(MD5_LONG)(len>>29);	/* might cause compiler warning on 16-bit */
+	c->Nl = l;
+
+	n = c->num;
+	if (n != 0) {
+		p = (unsigned char *)c->data;
+
+		if (len >= MD5_CBLOCK || len + n >= MD5_CBLOCK) {
+			memcpy(p + n, data, MD5_CBLOCK - n);
+			md5_block_data_order(c, p, 1);
+			n = MD5_CBLOCK - n;
+			data += n;
+			len -= n;
+			c->num = 0;
+			memset(p, 0, MD5_CBLOCK);	/* keep it zeroed */
+		} else {
+			memcpy(p + n, data, len);
+			c->num += (unsigned int)len;
+			return 1;
+		}
+	}
+
+	n = len/MD5_CBLOCK;
+	if (n > 0) {
+		md5_block_data_order (c, data, n);
+		n    *= MD5_CBLOCK;
+		data += n;
+		len -= n;
+	}
+
+	if (len != 0) {
+		p = (unsigned char *)c->data;
+		c->num = (unsigned int)len;
+		memcpy (p, data, len);
+	}
+	return 1;
+}
+
+void
+MD5_Transform(MD5_CTX *c, const unsigned char *data)
+{
+	md5_block_data_order(c, data, 1);
+}
+
+int
+MD5_Final(unsigned char *md, MD5_CTX *c)
+{
+	unsigned char *p = (unsigned char *)c->data;
+	size_t n = c->num;
+
+	p[n] = 0x80; /* there is always room for one */
+	n++;
+
+	if (n > (MD5_CBLOCK - 8)) {
+		memset(p + n, 0, MD5_CBLOCK - n);
+		n = 0;
+		md5_block_data_order(c, p, 1);
+	}
+	memset(p + n, 0, MD5_CBLOCK - 8 - n);
+
+	p += MD5_CBLOCK - 8;
+#if   defined(DATA_ORDER_IS_BIG_ENDIAN)
+	HOST_l2c(c->Nh, p);
+	HOST_l2c(c->Nl, p);
+#elif defined(DATA_ORDER_IS_LITTLE_ENDIAN)
+	HOST_l2c(c->Nl, p);
+	HOST_l2c(c->Nh, p);
+#endif
+	p -= MD5_CBLOCK;
+	md5_block_data_order(c, p, 1);
+	c->num = 0;
+	memset(p, 0, MD5_CBLOCK);
+
+#ifndef HASH_MAKE_STRING
+#error "HASH_MAKE_STRING must be defined!"
+#else
+	HASH_MAKE_STRING(c, md);
+#endif
+
+	return 1;
+}
 LCRYPTO_ALIAS(MD5_Update);
 LCRYPTO_ALIAS(MD5_Transform);
 LCRYPTO_ALIAS(MD5_Final);
-- 
2.20.1