From 8970c4933c3dc80f3f5d64686d342c6821624b7c Mon Sep 17 00:00:00 2001
From: Joost Rijneveld <joost@joostrijneveld.nl>
Date: Mon, 23 Oct 2017 13:03:07 +0200
Subject: [PATCH] Document and simplify library usage

---
 Makefile         | 4 ++--
 README.md        | 4 ++++
 test/test_wots.c | 1 -
 3 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/Makefile b/Makefile
index c3e2ae1..45e8d62 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,6 @@
 CC = /usr/bin/gcc
 CFLAGS = -Wall -g -O3 -Wextra -Wpedantic
-LDLIBS =  -lcrypto -lm
+LDLIBS =  -lcrypto
 
 SOURCES = params.c hash.c fips202.c hash_address.c randombytes.c wots.c xmss.c xmss_core.c xmss_commons.c
 HEADERS = params.h hash.h fips202.h hash_address.h randombytes.h wots.h xmss.h xmss_core.h xmss_commons.h
@@ -34,7 +34,7 @@ test/%: test/%.c $(SOURCES) $(OBJS) $(HEADERS)
 	$(CC) $(CFLAGS) -o $@ $(SOURCES) $< $(LDLIBS)
 
 test/test_wots: params.c hash.c fips202.c hash_address.c randombytes.c wots.c xmss_commons.c test/test_wots.c params.h hash.h fips202.h hash_address.h randombytes.h wots.h xmss_commons.h
-	$(CC) $(CFLAGS) params.c hash.c fips202.c hash_address.c randombytes.c wots.c xmss_commons.c test/test_wots.c -o $@ -lcrypto -lm
+	$(CC) $(CFLAGS) params.c hash.c fips202.c hash_address.c randombytes.c wots.c xmss_commons.c test/test_wots.c -o $@ -lcrypto
 
 clean:
 	-$(RM) $(TESTS)
diff --git a/README.md b/README.md
index b37de64..93d2fdc 100644
--- a/README.md
+++ b/README.md
@@ -8,6 +8,10 @@ _While the behavior of the code in this repository is supposed to be stable, the
 
 _When using the current code base, please be careful, expect changes and watch this document for further documentation._
 
+### Dependencies
+
+For the SHA-2 hash functions (i.e. SHA-256 and SHA-512), we rely on OpenSSL. Make sure to install the OpenSSL development headers. On Debian-based systems, this is achieved by installing the OpenSSL development package `libssl-dev`.
+
 ### License
 
 This reference implementation was written by Andreas Hülsing and Joost Rijneveld. All included code is available under the CC0 1.0 Universal Public Domain Dedication.
diff --git a/test/test_wots.c b/test/test_wots.c
index 3c3a29a..3aa9c46 100644
--- a/test/test_wots.c
+++ b/test/test_wots.c
@@ -1,5 +1,4 @@
 #include <stdio.h>
-#include <math.h>
 #include <stdint.h>
 #include "../wots.h"
 #include "../randombytes.h"