[U-Boot] [PATCH 3/4] [RFC] [v2] hash: Add function to find hash_algo struct with progressive hash

[Ruchika Gupta]

The hash_algo structure has some implementations in which
progressive hash API's are not defined. These are basically the
hardware based implementations of SHA. An API is added to find
the algo which has progressive hash API's defined. This can then
be integrated with RSA checksum library which used Progressive
Hash API's.

Signed-off-by: Ruchika Gupta <ruchika.gupta at freescale.com>
CC: Simon Glass <sjg at chromium.org>
---
Changes in v2 :
Added commit message

 common/hash.c  | 35 ++++++++++++++++++++++++++---------
 include/hash.h | 15 +++++++++++++++
 2 files changed, 41 insertions(+), 9 deletions(-)

diff --git a/common/hash.c b/common/hash.c
index 12d6759..87263df 100644
--- a/common/hash.c
+++ b/common/hash.c
@@ -20,7 +20,7 @@
 #include <asm/io.h>
 #include <asm/errno.h>
 
-#ifdef CONFIG_CMD_SHA1SUM
+#ifdef CONFIG_SHA256
 static int hash_init_sha1(struct hash_algo *algo, void **ctxp)
 {
 	sha1_context *ctx = malloc(sizeof(sha1_context));
@@ -125,12 +125,8 @@ static struct hash_algo hash_algo[] = {
 		CHUNKSZ_SHA256,
 	},
 #endif
-	/*
-	 * This is CONFIG_CMD_SHA1SUM instead of CONFIG_SHA1 since otherwise
-	 * it bloats the code for boards which use SHA1 but not the 'hash'
-	 * or 'sha1sum' commands.
-	 */
-#ifdef CONFIG_CMD_SHA1SUM
+
+#ifdef CONFIG_SHA1
 	{
 		"sha1",
 		SHA1_SUM_LEN,
@@ -140,7 +136,6 @@ static struct hash_algo hash_algo[] = {
 		hash_update_sha1,
 		hash_finish_sha1,
 	},
-#define MULTI_HASH
 #endif
 #ifdef CONFIG_SHA256
 	{
@@ -152,7 +147,6 @@ static struct hash_algo hash_algo[] = {
 		hash_update_sha256,
 		hash_finish_sha256,
 	},
-#define MULTI_HASH
 #endif
 	{
 		"crc32",
@@ -165,6 +159,10 @@ static struct hash_algo hash_algo[] = {
 	},
 };
 
+#if defined(CONFIG_SHA256) || defined(CONFIG_CMD_SHA1SUM)
+#define MULTI_HASH
+#endif
+
 #if defined(CONFIG_HASH_VERIFY) || defined(CONFIG_CMD_HASH)
 #define MULTI_HASH
 #endif
@@ -311,6 +309,25 @@ int hash_lookup_algo(const char *algo_name, struct hash_algo **algop)
 	return -EPROTONOSUPPORT;
 }
 
+int hash_progressive_lookup_algo(const char *algo_name,
+				 struct hash_algo **algop)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(hash_algo); i++) {
+		if (!strcmp(algo_name, hash_algo[i].name)) {
+			if (hash_algo[i].hash_init) {
+				*algop = &hash_algo[i];
+				return 0;
+			}
+		}
+	}
+
+	debug("Unknown hash algorithm '%s'\n", algo_name);
+	return -EPROTONOSUPPORT;
+}
+
+
 void hash_show(struct hash_algo *algo, ulong addr, ulong len, uint8_t *output)
 {
 	int i;
diff --git a/include/hash.h b/include/hash.h
index d8ec4f0..059f84e 100644
--- a/include/hash.h
+++ b/include/hash.h
@@ -128,6 +128,21 @@ int hash_block(const char *algo_name, const void *data, unsigned int len,
 int hash_lookup_algo(const char *algo_name, struct hash_algo **algop);
 
 /**
+ * hash_progressive_lookup_algo() - Look up the hash_algo struct with progressive
+ *				    hash support for an algorithm
+ *
+ * The function returns the pointer to the struct or -EPROTONOSUPPORT if the
+ * algorithm is not available with progressive hash support.
+ *
+ * @algo_name: Hash algorithm to look up
+ * @algop: Pointer to the hash_algo struct if found
+ *
+ * @return 0 if ok, -EPROTONOSUPPORT for an unknown algorithm.
+ */
+int hash_progressive_lookup_algo(const char *algo_name,
+				 struct hash_algo **algop);
+
+/**
  * hash_show() - Print out a hash algorithm and value
  *
  * You will get a message like this (without a newline at the end):
-- 
1.8.1.4