[PATCH v2 07/14] fip: add function to calculate a sha256 over FIP image

[Sascha Hauer <s.hauer@pengutronix.de>]

This adds fip_sha256() to calculate a sha256 over a FIP image.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 include/fiptool.h |  3 +++
 lib/fip.c         | 23 ++++++++++++++++++++++-
 2 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/include/fiptool.h b/include/fiptool.h
index bb63a79c16..73b0fbe398 100644
--- a/include/fiptool.h
+++ b/include/fiptool.h
@@ -38,6 +38,7 @@ struct fip_state {
 	size_t nr_image_descs;
 	int verbose;
 	void *buffer;
+	size_t bufsize;
 	bool buf_no_free;
 };
 
@@ -100,4 +101,6 @@ extern toc_entry_t plat_def_toc_entries[];
 
 struct fip_state *fip_image_open(const char *filename, size_t offset);
 
+int fip_sha256(struct fip_state *fip, char *hash);
+
 #endif /* FIPTOOL_H */
diff --git a/lib/fip.c b/lib/fip.c
index 8086b43412..7a5e3dc844 100644
--- a/lib/fip.c
+++ b/lib/fip.c
@@ -24,6 +24,7 @@
 #include <libfile.h>
 #include <fs.h>
 #include <linux/kernel.h>
+#include <digest.h>
 
 #include <fip.h>
 #include <fiptool.h>
@@ -168,6 +169,7 @@ static int fip_do_parse_buf(struct fip_state *fip, void *buf, size_t size,
 	int terminated = 0;
 
 	fip->buffer = buf;
+	fip->bufsize = size;
 
 	bufend = fip->buffer + size;
 
@@ -570,10 +572,29 @@ struct fip_state *fip_image_open(const char *filename, size_t offset)
 	close(fd);
 
 	return fip_state;
-
 err:
 	close(fd);
 	fip_free(fip_state);
 
 	return ERR_PTR(ret);
 }
+
+int fip_sha256(struct fip_state *fip, char *hash)
+{
+	struct digest *d;
+	int ret;
+
+	d = digest_alloc_by_algo(HASH_ALGO_SHA256);
+	if (!d)
+		return -ENOSYS;
+
+	digest_init(d);
+
+	digest_update(d, fip->buffer, fip->bufsize);
+
+	ret = digest_final(d, hash);
+
+	digest_free(d);
+
+	return ret;
+}

-- 
2.39.5