vboot2: Add host library functions to read/write files and objects

And unit tests for them.

Move roundup32() into hostlib.

Fix WriteFile() returning success even if it failed to write to the file.

BUG=chromium:423882
BRANCH=none
TEST=VBOOT2=1 make runtests

Change-Id: I8a115335c088dc5c66c88423d1ccbda7eaca1996
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/230844

3 files changed, 126 insertions, 0 deletions

diff --git a/host/lib/host_misc.c b/host/lib/host_misc.c
index adc39420..3fb9b24e 100644
--- a/host/lib/host_misc.c
+++ b/host/lib/host_misc.c
@@ -108,6 +108,7 @@ int WriteFile(const char* filename, const void *data, uint64_t size) {
     VBDEBUG(("Unable to write to file %s\n", filename));
     fclose(f);
     unlink(filename);  /* Delete any partial file */
+    return 1;
   }
 
   fclose(f);
diff --git a/host/lib/host_misc2.c b/host/lib/host_misc2.c
new file mode 100644
index 00000000..88b58f5b
--- /dev/null
+++ b/host/lib/host_misc2.c
@@ -0,0 +1,84 @@
+/* Copyright (c) 2014 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ *
+ * Host functions for verified boot.
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+
+#include "2sysincludes.h"
+#include "2common.h"
+#include "host_common.h"
+
+int vb2_read_file(const char *filename, uint8_t **data_ptr, uint32_t *size_ptr)
+{
+	FILE *f;
+	uint8_t *buf;
+	long size;
+
+	*data_ptr = NULL;
+	*size_ptr = 0;
+
+	f = fopen(filename, "rb");
+	if (!f) {
+		VB2_DEBUG("Unable to open file %s\n", filename);
+		return VB2_ERROR_READ_FILE_OPEN;
+	}
+
+	fseek(f, 0, SEEK_END);
+	size = ftell(f);
+	rewind(f);
+
+	if (size < 0 || size > UINT32_MAX) {
+		fclose(f);
+		return VB2_ERROR_READ_FILE_SIZE;
+	}
+
+	buf = malloc(size);
+	if (!buf) {
+		fclose(f);
+		return VB2_ERROR_READ_FILE_ALLOC;
+	}
+
+	if(1 != fread(buf, size, 1, f)) {
+		VB2_DEBUG("Unable to read file %s\n", filename);
+		fclose(f);
+		free(buf);
+		return VB2_ERROR_READ_FILE_DATA;
+	}
+
+	fclose(f);
+
+	*data_ptr = buf;
+	*size_ptr = size;
+	return VB2_SUCCESS;
+}
+
+int vb2_write_file(const char *filename, const void *buf, uint32_t size)
+{
+	FILE *f = fopen(filename, "wb");
+
+	if (!f) {
+		VB2_DEBUG("Unable to open file %s\n", filename);
+		return VB2_ERROR_WRITE_FILE_OPEN;
+	}
+
+	if (1 != fwrite(buf, size, 1, f)) {
+		VB2_DEBUG("Unable to write to file %s\n", filename);
+		fclose(f);
+		unlink(filename);  /* Delete any partial file */
+		return VB2_ERROR_WRITE_FILE_DATA;
+	}
+
+	fclose(f);
+	return VB2_SUCCESS;
+}
+
+int vb2_write_object(const char *filename, const void *buf)
+{
+	const struct vb2_struct_common *cptr = buf;
+
+	return vb2_write_file(filename, buf, cptr->total_size);
+}
diff --git a/host/lib/include/host_misc.h b/host/lib/include/host_misc.h
index b2b4fb94..2e18d90b 100644
--- a/host/lib/include/host_misc.h
+++ b/host/lib/include/host_misc.h
@@ -43,4 +43,45 @@ int ReadFileBit(const char* filename, int bitmask);
  * Returns 0 if success, 1 if error. */
 int WriteFile(const char* filename, const void *data, uint64_t size);
 
+/**
+ * Read data from a file into a newly allocated buffer.
+ *
+ * @param filename	Name of file to read from
+ * @param data_ptr	On exit, pointer to newly allocated buffer with data
+ *			will be stored here.  Caller must free() the buffer
+ *			when done with it.
+ * @param size_ptr	On exit, size of data will be stored here.
+ * @return VB2_SUCCESS, or non-zero if error.
+ */
+int vb2_read_file(const char *filename, uint8_t **data_ptr, uint32_t *size_ptr);
+
+/**
+ * Write data to a file from a buffer.
+ *
+ * @param filename	Name of file to write to
+ * @param buf		Buffer to write
+ * @param size		Number of bytes of data to write
+ * @return VB2_SUCCESS, or non-zero if error.
+ */
+int vb2_write_file(const char *filename, const void *buf, uint32_t size);
+
+/**
+ * Write a buffer which starts with a standard vb2_struct_common header.
+ *
+ * Determines the buffer size from the common header total size field.
+ *
+ * @param filename	Name of file to write to
+ * @param buf		Buffer to write
+ * @return VB2_SUCCESS, or non-zero if error.
+ */
+int vb2_write_object(const char *filename, const void *buf);
+
+/**
+ * Round up a size to a multiple of 32 bits (4 bytes).
+ */
+static __inline const uint32_t roundup32(uint32_t v)
+{
+	return (v + 3) & ~3;
+}
+
 #endif  /* VBOOT_REFERENCE_HOST_MISC_H_ */