Add generic hash API
We have a SHA1 command and want to add a SHA256 command also. Instead of
duplicating the code, create a generic hash API which can process
commands for different algorithms.
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/include/hash.h b/include/hash.h
new file mode 100644
index 0000000..34ba558
--- /dev/null
+++ b/include/hash.h
@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) 2012 The Chromium OS Authors.
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program 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.
+ *
+ * This program 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., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#ifndef _HASH_H
+#define _HASH_H
+
+#ifdef CONFIG_SHA1SUM_VERIFY
+#define CONFIG_HASH_VERIFY
+#endif
+
+struct hash_algo {
+ const char *name; /* Name of algorithm */
+ int digest_size; /* Length of digest */
+ /**
+ * hash_func_ws: Generic hashing function
+ *
+ * This is the generic prototype for a hashing function. We only
+ * have the watchdog version at present.
+ *
+ * @input: Input buffer
+ * @ilen: Input buffer length
+ * @output: Checksum result (length depends on algorithm)
+ * @chunk_sz: Trigger watchdog after processing this many bytes
+ */
+ void (*hash_func_ws)(const unsigned char *input, unsigned int ilen,
+ unsigned char *output, unsigned int chunk_sz);
+ int chunk_size; /* Watchdog chunk size */
+};
+
+/*
+ * Maximum digest size for all algorithms we support. Having this value
+ * avoids a malloc() or C99 local declaration in common/cmd_hash.c.
+ */
+#define HASH_MAX_DIGEST_SIZE 32
+
+/**
+ * hash_command: Process a hash command for a particular algorithm
+ *
+ * This common function is used to implement specific hash commands.
+ *
+ * @algo_name: Hash algorithm being used
+ * @verify: Non-zero to enable verify mode
+ * @cmdtp: Pointer to command table entry
+ * @flag: Some flags normally 0 (see CMD_FLAG_.. above)
+ * @argc: Number of arguments (arg 0 must be the command text)
+ * @argv: Arguments
+ */
+int hash_command(const char *algo_name, int verify, cmd_tbl_t *cmdtp, int flag,
+ int argc, char * const argv[]);
+
+#endif