From 4272ff9ca3f350a9a48bb2ac8efa01ffdd0675a7 Mon Sep 17 00:00:00 2001
From: kaleb-himes <kaleb@wolfssl.com>
Date: Thu, 24 Sep 2020 11:19:32 -0600
Subject: [PATCH] Add simple example to hash contents of a file

---
 .gitignore         |  1 +
 hash/Makefile      | 38 ++++++++++++++++++++
 hash/sha256-hash.c | 89 ++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 128 insertions(+)
 create mode 100644 hash/Makefile
 create mode 100644 hash/sha256-hash.c

diff --git a/.gitignore b/.gitignore
index e927ae87..4bc78c42 100644
--- a/.gitignore
+++ b/.gitignore
@@ -22,6 +22,7 @@
 *.x86_64
 *.hex
 *app
+*run
 
 # IDE Temp Files
 **/*.swp
diff --git a/hash/Makefile b/hash/Makefile
new file mode 100644
index 00000000..8db47c14
--- /dev/null
+++ b/hash/Makefile
@@ -0,0 +1,38 @@
+CC := gcc -fsanitize=address
+program_NAME := run
+program_C_SRCS := $(wildcard *.c)
+program_CXX_SRCS := $(wildcard *.cpp)
+program_C_OBJS := ${program_C_SRCS:.c=.o}
+program_CXX_OBJS := ${program_CXX_SRCS:.cpp=.o}
+program_OBJS := $(program_C_OBJS) $(program_CXX_OBJS)
+program_INCLUDE_DIRS :=
+program_LIBRARY_DIRS :=
+program_LIBRARIES :=
+
+#WOLF_INSTALL_DIR := /Users/kalebhimes/work/testDir/wolf-install-dir-for-testing
+WOLF_INSTALL_DIR := /usr/local/lib
+program_INCLUDE_DIRS += $(WOLF_INSTALL_DIR)/include
+program_INCLUDE_DIRS += ./include
+program_LIBRARY_DIRS += $(WOLF_INSTALL_DIR)/lib
+program_LIBRARIES += wolfssl
+
+CPPFLAGS += $(foreach includedir,$(program_INCLUDE_DIRS),-I$(includedir))
+#CPPFLAGS += -Werror
+#CPPFLAGS += -Weverything
+#CPPFLAGS += -Wsign-conversion
+#CPPFLAGS += -Wshorten-64-to-32 #NOTE: Not supported on most linux distros.
+LDFLAGS += $(foreach librarydir,$(program_LIBRARY_DIRS),-L$(librarydir))
+LDFLAGS += $(foreach library,$(program_LIBRARIES),-l$(library))
+
+.PHONY: all clean distclean
+
+all: $(program_NAME)
+
+$(program_NAME): $(program_OBJS)
+	$(CC) $(CPPFLAGS) $(program_OBJS) -o $(program_NAME) $(LDFLAGS) 
+
+clean:
+	@- $(RM) $(program_NAME)
+	@- $(RM) $(program_OBJS)
+
+distclean: clean
diff --git a/hash/sha256-hash.c b/hash/sha256-hash.c
new file mode 100644
index 00000000..5fdb09e8
--- /dev/null
+++ b/hash/sha256-hash.c
@@ -0,0 +1,89 @@
+/* sha256-hash.c
+ *
+ * Copyright (C) 2006-2020 wolfSSL Inc.
+ *
+ * This file is part of wolfSSL.
+ *
+ * wolfSSL is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * wolfSSL is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
+ */
+
+
+#include <wolfssl/options.h>
+#include <wolfssl/ssl.h>
+#include <wolfssl/wolfcrypt/hash.h>
+
+void usage(void)
+{
+    printf("./run <file to hash>\n");
+    exit(-99);
+}
+
+int main(int argc, char** argv)
+{
+    int ret = -1;
+#ifndef NO_SHA256
+    byte  hash[WC_SHA256_DIGEST_SIZE];
+    byte* rawInput;
+    FILE* inputStream;
+    char* fName = NULL;
+    int numBytes = 0;
+    int fileLength = 0;
+
+    if (argc < 2)
+        usage();
+    fName = argv[1];
+    printf("Hash input file %s\n", fName);
+
+    inputStream = fopen(fName, "rb");
+    if (inputStream == NULL) {
+        printf("ERROR: Unable to open file\n");
+        return -1;
+    }
+
+    /* find length of the file */
+    fseek(inputStream, 0, SEEK_END);
+    fileLength = (int) ftell(inputStream);
+    fseek(inputStream, 0, SEEK_SET); 
+
+    /* allocate buffer based on file size */
+    rawInput = (byte*) XMALLOC(fileLength*sizeof(byte), NULL,
+                               DYNAMIC_TYPE_TMP_BUFFER);
+
+    numBytes = fread(rawInput, 1, fileLength, inputStream);
+    if (numBytes != fileLength) {
+        printf("ERROR: Failed to read the entire file\n");
+        fclose(inputStream);
+        XFREE(rawInput, NULL, DYNAMIC_TYPE_TMP_BUFFER);
+        return -2;
+    }
+
+    ret = wc_Sha256Hash(rawInput, numBytes, hash);
+    if (ret != 0)
+        printf("ERROR: Hash operation failed");
+    else {
+        int i;
+        printf("Hash result is: ");
+        for (i = 0; i < WC_SHA256_DIGEST_SIZE; i++)
+            printf("%02x", hash[i]);
+        printf("\n");
+    }
+
+    fclose(inputStream);
+    XFREE(rawInput, NULL, DYNAMIC_TYPE_TMP_BUFFER);
+#else
+    printf("Please enabling sha256 and then try again\n");
+#endif
+    return ret;
+}