1 files changed, 86 insertions, 0 deletions
diff --git a/dhcpcd/crypt/hmac_md5.c b/dhcpcd/crypt/hmac_md5.c
new file mode 100644
index 00000000..06ea465a
--- /dev/null
+++ b/dhcpcd/crypt/hmac_md5.c
@@ -0,0 +1,86 @@
+/*
+ * dhcpcd - DHCP client daemon
+ * Copyright (c) 2006-2014 Roy Marples <roy@marples.name>
+ * All rights reserved
+
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <inttypes.h>
+#include <string.h>
+
+#include "crypt.h"
+
+#ifdef HAVE_MD5_H
+#include <md5.h>
+#else
+#include "md5.h"
+#endif
+
+#define HMAC_PAD_LEN	64
+#define IPAD		0x36
+#define OPAD		0x5C
+
+/* hmac_md5 as per RFC3118 */
+void
+hmac_md5(const uint8_t *text, int text_len,
+    const uint8_t *key, int key_len,
+    uint8_t *digest)
+{
+	uint8_t k_ipad[HMAC_PAD_LEN], k_opad[HMAC_PAD_LEN];
+	uint8_t tk[MD5_DIGEST_LENGTH];
+	int i;
+	MD5_CTX context;
+
+	/* Ensure key is no bigger than HMAC_PAD_LEN */
+	if (key_len > HMAC_PAD_LEN) {
+		MD5Init(&context);
+		MD5Update(&context, key, key_len);
+		MD5Final(tk, &context);
+		key = tk;
+		key_len = MD5_DIGEST_LENGTH;
+	}
+
+	/* store key in pads */
+	memcpy(k_ipad, key, key_len);
+	memcpy(k_opad, key, key_len);
+	memset(k_ipad + key_len, 0, sizeof(k_ipad) - key_len);
+	memset(k_opad + key_len, 0, sizeof(k_opad) - key_len);
+
+	/* XOR key with ipad and opad values */
+	for (i = 0; i < HMAC_PAD_LEN; i++) {
+		k_ipad[i] ^= IPAD;
+		k_opad[i] ^= OPAD;
+	}
+
+	/* inner MD5 */
+	MD5Init(&context);
+	MD5Update(&context, k_ipad, HMAC_PAD_LEN);
+	MD5Update(&context, text, text_len);
+	MD5Final(digest, &context);
+
+	/* outer MD5 */
+	MD5Init(&context);
+	MD5Update(&context, k_opad, HMAC_PAD_LEN);
+	MD5Update(&context, digest, MD5_DIGEST_LENGTH);
+	MD5Final(digest, &context);
+}