[CRYPTO] padlock: Driver for SHA1 / SHA256 algorithms
Support for SHA1 / SHA256 algorithms in VIA C7 processors.
Signed-off-by: Michal Ludvig <michal@logix.cz>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/drivers/crypto/padlock-sha.c b/drivers/crypto/padlock-sha.c
new file mode 100644
index 0000000..f701003
--- /dev/null
+++ b/drivers/crypto/padlock-sha.c
@@ -0,0 +1,339 @@
+/*
+ * Cryptographic API.
+ *
+ * Support for VIA PadLock hardware crypto engine.
+ *
+ * Copyright (c) 2006 Michal Ludvig <michal@logix.cz>
+ *
+ * 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.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/crypto.h>
+#include <linux/cryptohash.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/scatterlist.h>
+#include "padlock.h"
+
+#define SHA1_DEFAULT_FALLBACK "sha1-generic"
+#define SHA1_DIGEST_SIZE 20
+#define SHA1_HMAC_BLOCK_SIZE 64
+
+#define SHA256_DEFAULT_FALLBACK "sha256-generic"
+#define SHA256_DIGEST_SIZE 32
+#define SHA256_HMAC_BLOCK_SIZE 64
+
+static char *sha1_fallback = SHA1_DEFAULT_FALLBACK;
+static char *sha256_fallback = SHA256_DEFAULT_FALLBACK;
+
+module_param(sha1_fallback, charp, 0644);
+module_param(sha256_fallback, charp, 0644);
+
+MODULE_PARM_DESC(sha1_fallback, "Fallback driver for SHA1. Default is "
+ SHA1_DEFAULT_FALLBACK);
+MODULE_PARM_DESC(sha256_fallback, "Fallback driver for SHA256. Default is "
+ SHA256_DEFAULT_FALLBACK);
+
+struct padlock_sha_ctx {
+ char *data;
+ size_t used;
+ int bypass;
+ void (*f_sha_padlock)(const char *in, char *out, int count);
+ struct crypto_tfm *fallback_tfm;
+};
+
+static inline struct padlock_sha_ctx *ctx(struct crypto_tfm *tfm)
+{
+ return (struct padlock_sha_ctx *)(crypto_tfm_ctx(tfm));
+}
+
+/* We'll need aligned address on the stack */
+#define NEAREST_ALIGNED(ptr) \
+ ((void *)ALIGN((size_t)(ptr), PADLOCK_ALIGNMENT))
+
+static struct crypto_alg sha1_alg, sha256_alg;
+
+static void padlock_sha_bypass(struct crypto_tfm *tfm)
+{
+ if (ctx(tfm)->bypass)
+ return;
+
+ BUG_ON(!ctx(tfm)->fallback_tfm);
+
+ crypto_digest_init(ctx(tfm)->fallback_tfm);
+ if (ctx(tfm)->data && ctx(tfm)->used) {
+ struct scatterlist sg;
+
+ sg_set_buf(&sg, ctx(tfm)->data, ctx(tfm)->used);
+ crypto_digest_update(ctx(tfm)->fallback_tfm, &sg, 1);
+ }
+
+ ctx(tfm)->used = 0;
+ ctx(tfm)->bypass = 1;
+}
+
+static void padlock_sha_init(struct crypto_tfm *tfm)
+{
+ ctx(tfm)->used = 0;
+ ctx(tfm)->bypass = 0;
+}
+
+static void padlock_sha_update(struct crypto_tfm *tfm,
+ const uint8_t *data, unsigned int length)
+{
+ /* Our buffer is always one page. */
+ if (unlikely(!ctx(tfm)->bypass &&
+ (ctx(tfm)->used + length > PAGE_SIZE)))
+ padlock_sha_bypass(tfm);
+
+ if (unlikely(ctx(tfm)->bypass)) {
+ struct scatterlist sg;
+ BUG_ON(!ctx(tfm)->fallback_tfm);
+ sg_set_buf(&sg, (uint8_t *)data, length);
+ crypto_digest_update(ctx(tfm)->fallback_tfm, &sg, 1);
+ return;
+ }
+
+ memcpy(ctx(tfm)->data + ctx(tfm)->used, data, length);
+ ctx(tfm)->used += length;
+}
+
+static inline void padlock_output_block(uint32_t *src,
+ uint32_t *dst, size_t count)
+{
+ while (count--)
+ *dst++ = swab32(*src++);
+}
+
+void padlock_do_sha1(const char *in, char *out, int count)
+{
+ /* We can't store directly to *out as it may be unaligned. */
+ /* BTW Don't reduce the buffer size below 128 Bytes!
+ * PadLock microcode needs it that big. */
+ char buf[128+16];
+ char *result = NEAREST_ALIGNED(buf);
+
+ ((uint32_t *)result)[0] = 0x67452301;
+ ((uint32_t *)result)[1] = 0xEFCDAB89;
+ ((uint32_t *)result)[2] = 0x98BADCFE;
+ ((uint32_t *)result)[3] = 0x10325476;
+ ((uint32_t *)result)[4] = 0xC3D2E1F0;
+
+ asm volatile (".byte 0xf3,0x0f,0xa6,0xc8" /* rep xsha1 */
+ : "+S"(in), "+D"(result)
+ : "c"(count), "a"(0));
+
+ padlock_output_block((uint32_t *)result, (uint32_t *)out, 5);
+}
+
+void padlock_do_sha256(const char *in, char *out, int count)
+{
+ /* We can't store directly to *out as it may be unaligned. */
+ /* BTW Don't reduce the buffer size below 128 Bytes!
+ * PadLock microcode needs it that big. */
+ char buf[128+16];
+ char *result = NEAREST_ALIGNED(buf);
+
+ ((uint32_t *)result)[0] = 0x6A09E667;
+ ((uint32_t *)result)[1] = 0xBB67AE85;
+ ((uint32_t *)result)[2] = 0x3C6EF372;
+ ((uint32_t *)result)[3] = 0xA54FF53A;
+ ((uint32_t *)result)[4] = 0x510E527F;
+ ((uint32_t *)result)[5] = 0x9B05688C;
+ ((uint32_t *)result)[6] = 0x1F83D9AB;
+ ((uint32_t *)result)[7] = 0x5BE0CD19;
+
+ asm volatile (".byte 0xf3,0x0f,0xa6,0xd0" /* rep xsha256 */
+ : "+S"(in), "+D"(result)
+ : "c"(count), "a"(0));
+
+ padlock_output_block((uint32_t *)result, (uint32_t *)out, 8);
+}
+
+static void padlock_sha_final(struct crypto_tfm *tfm, uint8_t *out)
+{
+ if (unlikely(ctx(tfm)->bypass)) {
+ BUG_ON(!ctx(tfm)->fallback_tfm);
+ crypto_digest_final(ctx(tfm)->fallback_tfm, out);
+ ctx(tfm)->bypass = 0;
+ return;
+ }
+
+ /* Pass the input buffer to PadLock microcode... */
+ ctx(tfm)->f_sha_padlock(ctx(tfm)->data, out, ctx(tfm)->used);
+
+ ctx(tfm)->used = 0;
+}
+
+static int padlock_cra_init(struct crypto_tfm *tfm, const char *fallback_driver_name)
+{
+ /* For now we'll allocate one page. This
+ * could eventually be configurable one day. */
+ ctx(tfm)->data = (char *)__get_free_page(GFP_KERNEL);
+ if (!ctx(tfm)->data)
+ return -ENOMEM;
+
+ /* Allocate a fallback and abort if it failed. */
+ ctx(tfm)->fallback_tfm = crypto_alloc_tfm(fallback_driver_name, 0);
+ if (!ctx(tfm)->fallback_tfm) {
+ printk(KERN_WARNING PFX "Fallback driver '%s' could not be loaded!\n",
+ fallback_driver_name);
+ free_page((unsigned long)(ctx(tfm)->data));
+ return -ENOENT;
+ }
+
+ return 0;
+}
+
+static int padlock_sha1_cra_init(struct crypto_tfm *tfm)
+{
+ ctx(tfm)->f_sha_padlock = padlock_do_sha1;
+
+ return padlock_cra_init(tfm, sha1_fallback);
+}
+
+static int padlock_sha256_cra_init(struct crypto_tfm *tfm)
+{
+ ctx(tfm)->f_sha_padlock = padlock_do_sha256;
+
+ return padlock_cra_init(tfm, sha256_fallback);
+}
+
+static void padlock_cra_exit(struct crypto_tfm *tfm)
+{
+ if (ctx(tfm)->data) {
+ free_page((unsigned long)(ctx(tfm)->data));
+ ctx(tfm)->data = NULL;
+ }
+
+ BUG_ON(!ctx(tfm)->fallback_tfm);
+ crypto_free_tfm(ctx(tfm)->fallback_tfm);
+ ctx(tfm)->fallback_tfm = NULL;
+}
+
+static struct crypto_alg sha1_alg = {
+ .cra_name = "sha1",
+ .cra_driver_name = "sha1-padlock",
+ .cra_priority = PADLOCK_CRA_PRIORITY,
+ .cra_flags = CRYPTO_ALG_TYPE_DIGEST,
+ .cra_blocksize = SHA1_HMAC_BLOCK_SIZE,
+ .cra_ctxsize = sizeof(struct padlock_sha_ctx),
+ .cra_module = THIS_MODULE,
+ .cra_list = LIST_HEAD_INIT(sha1_alg.cra_list),
+ .cra_init = padlock_sha1_cra_init,
+ .cra_exit = padlock_cra_exit,
+ .cra_u = {
+ .digest = {
+ .dia_digestsize = SHA1_DIGEST_SIZE,
+ .dia_init = padlock_sha_init,
+ .dia_update = padlock_sha_update,
+ .dia_final = padlock_sha_final,
+ }
+ }
+};
+
+static struct crypto_alg sha256_alg = {
+ .cra_name = "sha256",
+ .cra_driver_name = "sha256-padlock",
+ .cra_priority = PADLOCK_CRA_PRIORITY,
+ .cra_flags = CRYPTO_ALG_TYPE_DIGEST,
+ .cra_blocksize = SHA256_HMAC_BLOCK_SIZE,
+ .cra_ctxsize = sizeof(struct padlock_sha_ctx),
+ .cra_module = THIS_MODULE,
+ .cra_list = LIST_HEAD_INIT(sha256_alg.cra_list),
+ .cra_init = padlock_sha256_cra_init,
+ .cra_exit = padlock_cra_exit,
+ .cra_u = {
+ .digest = {
+ .dia_digestsize = SHA256_DIGEST_SIZE,
+ .dia_init = padlock_sha_init,
+ .dia_update = padlock_sha_update,
+ .dia_final = padlock_sha_final,
+ }
+ }
+};
+
+static void __init padlock_sha_check_fallbacks(void)
+{
+ static struct crypto_tfm *tfm_sha1, *tfm_sha256;
+
+ /* We'll try to allocate one TFM for each fallback
+ * to test that the modules are available. */
+ tfm_sha1 = crypto_alloc_tfm(sha1_fallback, 0);
+ if (!tfm_sha1) {
+ printk(KERN_WARNING PFX "Couldn't load fallback module for '%s'. Tried '%s'.\n",
+ sha1_alg.cra_name, sha1_fallback);
+ } else {
+ printk(KERN_NOTICE PFX "Fallback for '%s' is driver '%s' (prio=%d)\n", sha1_alg.cra_name,
+ crypto_tfm_alg_driver_name(tfm_sha1), crypto_tfm_alg_priority(tfm_sha1));
+ crypto_free_tfm(tfm_sha1);
+ }
+
+ tfm_sha256 = crypto_alloc_tfm(sha256_fallback, 0);
+ if (!tfm_sha256) {
+ printk(KERN_WARNING PFX "Couldn't load fallback module for '%s'. Tried '%s'.\n",
+ sha256_alg.cra_name, sha256_fallback);
+ } else {
+ printk(KERN_NOTICE PFX "Fallback for '%s' is driver '%s' (prio=%d)\n", sha256_alg.cra_name,
+ crypto_tfm_alg_driver_name(tfm_sha256), crypto_tfm_alg_priority(tfm_sha256));
+ crypto_free_tfm(tfm_sha256);
+ }
+}
+
+static int __init padlock_init(void)
+{
+ int rc = -ENODEV;
+
+ if (!cpu_has_phe) {
+ printk(KERN_ERR PFX "VIA PadLock Hash Engine not detected.\n");
+ return -ENODEV;
+ }
+
+ if (!cpu_has_phe_enabled) {
+ printk(KERN_ERR PFX "VIA PadLock detected, but not enabled. Hmm, strange...\n");
+ return -ENODEV;
+ }
+
+ padlock_sha_check_fallbacks();
+
+ rc = crypto_register_alg(&sha1_alg);
+ if (rc)
+ goto out;
+
+ rc = crypto_register_alg(&sha256_alg);
+ if (rc)
+ goto out_unreg1;
+
+ printk(KERN_NOTICE PFX "Using VIA PadLock ACE for SHA1/SHA256 algorithms.\n");
+
+ return 0;
+
+out_unreg1:
+ crypto_unregister_alg(&sha1_alg);
+out:
+ printk(KERN_ERR PFX "VIA PadLock SHA1/SHA256 initialization failed.\n");
+ return rc;
+}
+
+static void __exit padlock_fini(void)
+{
+ crypto_unregister_alg(&sha1_alg);
+ crypto_unregister_alg(&sha256_alg);
+}
+
+module_init(padlock_init);
+module_exit(padlock_fini);
+
+MODULE_DESCRIPTION("VIA PadLock SHA1/SHA256 algorithms support.");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Michal Ludvig");
+
+MODULE_ALIAS("sha1-padlock");
+MODULE_ALIAS("sha256-padlock");
