Fix hash verification

Fix issue in parse_verify_sum() which swaps handling of env-var and *address.
Move hash_command() argc check earlier.
Cosmetic change on do_hash() variable declaration.
Improved help message for "hash" command.

Signed-off-by: Nikolay Dimitrov <picmaster@mail.bg>
Reviewed-by: Simon Glass <sjg@chromium.org>

common/cmd_hash.c

@@ -18,9 +18,9 @@
 static int do_hash(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
 	char *s;
-#ifdef CONFIG_HASH_VERIFY
 	int flags = HASH_FLAG_ENV;
 
+#ifdef CONFIG_HASH_VERIFY
 	if (argc < 4)
 		return CMD_RET_USAGE;
 	if (!strcmp(argv[1], "-v")) {
@@ -28,8 +28,6 @@ static int do_hash(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 		argc--;
 		argv++;
 	}
-#else
-	const int flags = HASH_FLAG_ENV;
 #endif
 	/* Move forward to 'algorithm' parameter */
 	argc--;
@@ -40,19 +38,19 @@ static int do_hash(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 }
 
 #ifdef CONFIG_HASH_VERIFY
-U_BOOT_CMD(
-	hash,	6,	1,	do_hash,
-	"compute hash message digest",
-	"algorithm address count [[*]sum_dest]\n"
-		"    - compute message digest [save to env var / *address]\n"
-	"hash -v algorithm address count [*]sum\n"
-		"    - verify hash of memory area with env var / *address"
-);
+#define HARGS 6
 #else
+#define HARGS 5
+#endif
+
 U_BOOT_CMD(
-	hash,	5,	1,	do_hash,
-	"compute message digest",
-	"algorithm address count [[*]sum_dest]\n"
+	hash,	HARGS,	1,	do_hash,
+	"compute hash message digest",
+	"algorithm address count [[*]hash_dest]\n"
 		"    - compute message digest [save to env var / *address]"
-);
+#ifdef CONFIG_HASH_VERIFY
+	"\nhash -v algorithm address count [*]hash\n"
+		"    - verify message digest of memory area to immediate value, \n"
+		"      env var or *address"
 #endif
+);

common/hash.c

@@ -256,7 +256,7 @@ static int parse_verify_sum(struct hash_algo *algo, char *verify_str,
 			env_var = 1;
 	}
 
-	if (env_var) {
+	if (!env_var) {
 		ulong addr;
 		void *buf;
 
@@ -347,7 +347,7 @@ int hash_command(const char *algo_name, int flags, cmd_tbl_t *cmdtp, int flag,
 {
 	ulong addr, len;
 
-	if (argc < 2)
+	if ((argc < 2) || ((flags & HASH_FLAG_VERIFY) && (argc < 3)))
 		return CMD_RET_USAGE;
 
 	addr = simple_strtoul(*argv++, NULL, 16);
@@ -380,8 +380,6 @@ int hash_command(const char *algo_name, int flags, cmd_tbl_t *cmdtp, int flag,
 #else
 		if (0) {
 #endif
-			if (!argc)
-				return CMD_RET_USAGE;
 			if (parse_verify_sum(algo, *argv, vsum,
 					flags & HASH_FLAG_ENV)) {
 				printf("ERROR: %s does not contain a valid "