[PATCH 6/6] crypto: caam: add blob_gen driver
Steffen Trumtrar
s.trumtrar at pengutronix.de
Wed Oct 14 06:39:39 PDT 2015
The blob_gen driver allows generating and reading of red blobs on the
i.MX6 CAAM crypto core.
Signed-off-by: Steffen Trumtrar <s.trumtrar at pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl at pengutronix.de>
---
drivers/crypto/caam/Kconfig | 9 +
drivers/crypto/caam/Makefile | 1 +
drivers/crypto/caam/blob_gen.c | 485 +++++++++++++++++++++++++++++++++++++++++
3 files changed, 495 insertions(+)
create mode 100644 drivers/crypto/caam/blob_gen.c
diff --git a/drivers/crypto/caam/Kconfig b/drivers/crypto/caam/Kconfig
index d54754c7a89b..4466785358e7 100644
--- a/drivers/crypto/caam/Kconfig
+++ b/drivers/crypto/caam/Kconfig
@@ -35,3 +35,12 @@ config CRYPTO_DEV_FSL_CAAM_RINGSIZE
7 => 128
8 => 256
9 => 512
+
+config CRYPTO_DEV_FSL_CAAM_BLOB_GEN
+ bool "CAAM - Blob Generator (EXPERIMENTAL)"
+ depends on CRYPTO_DEV_FSL_CAAM
+ select BASE64
+ default n
+ help
+ Selecting this will register the device /dev/blob which can en/decapsulate
+ red blobs with the help of the CAAM.
diff --git a/drivers/crypto/caam/Makefile b/drivers/crypto/caam/Makefile
index cd46936fb6b4..6c126cf11dac 100644
--- a/drivers/crypto/caam/Makefile
+++ b/drivers/crypto/caam/Makefile
@@ -3,3 +3,4 @@
#
obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM) += ctrl.o error.o
obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM_JR) += jr.o
+obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM_BLOB_GEN) += blob_gen.o
diff --git a/drivers/crypto/caam/blob_gen.c b/drivers/crypto/caam/blob_gen.c
new file mode 100644
index 000000000000..7e5f990bc8e5
--- /dev/null
+++ b/drivers/crypto/caam/blob_gen.c
@@ -0,0 +1,485 @@
+/*
+ * Copyright (C) 2015 Pengutronix, Steffen Trumtrar <kernel at pengutronix.de>
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License version 2 as published by the
+ * Free Software Foundation.
+ */
+
+#include <asm/io.h>
+#include <base64.h>
+#include <common.h>
+#include <dma.h>
+#include <driver.h>
+#include <init.h>
+#include <fs.h>
+#include <fcntl.h>
+#include "intern.h"
+#include "desc.h"
+#include "desc_constr.h"
+#include "error.h"
+#include "jr.h"
+
+#define DRIVERNAME "blob"
+
+/*
+ * Upon completion, desc points to a buffer containing a CAAM job
+ * descriptor which encapsulates data into an externally-storable
+ * blob.
+ */
+#define INITIAL_DESCSZ 16
+/* 32 bytes key blob + 16 bytes HMAC identifier */
+#define BLOB_OVERHEAD (32 + 16)
+#define KEYMOD_LENGTH 16
+#define RED_BLOB_LENGTH 64
+#define MAX_BLOB_LEN 4096
+
+enum access_rights {
+ KERNEL,
+ KERNEL_EVM,
+ USERSPACE,
+};
+
+struct blob_priv;
+
+struct blob_job_result {
+ int err;
+};
+
+struct blob_param {
+ struct param_d *param;
+ char *value;
+};
+
+struct blob_dma_blob {
+ u8 data[MAX_BLOB_LEN];
+};
+
+struct blob_dma_modifier {
+ u8 data[KEYMOD_LENGTH];
+};
+
+struct blob_priv {
+ struct device_d *jrdev;
+ struct device_d dev;
+ struct blob_param modifier_param;
+ struct blob_param payload_param;
+ struct blob_param blob_param;
+ u32 __iomem *desc;
+ bool busy;
+ enum access_rights access;
+ unsigned int payload_size;
+ struct blob_dma_blob *red_blob;
+ struct blob_dma_blob *payload;
+ struct blob_dma_modifier *modifier;
+};
+
+static void jr_jobdesc_blob_decap(u32 __iomem *desc, u8 *keymod, u8 *blob,
+ u8 *plain_txt, u16 input_size)
+{
+ dma_addr_t dma_keymod;
+ dma_addr_t dma_plain;
+ dma_addr_t dma_blob;
+ u16 in_sz;
+ u16 out_sz;
+
+ dma_keymod = (dma_addr_t)keymod;
+ dma_plain = (dma_addr_t)plain_txt;
+ dma_blob = (dma_addr_t)blob;
+
+ in_sz = input_size;
+ out_sz = input_size - BLOB_OVERHEAD;
+
+ init_job_desc(desc, 0);
+ /*
+ * The key modifier can be used to differentiate specific data.
+ * Or to prevent replay attacks.
+ */
+ append_key(desc, dma_keymod, KEYMOD_LENGTH, CLASS_2);
+ append_seq_in_ptr(desc, dma_blob, in_sz, 0);
+ append_seq_out_ptr(desc, dma_plain, out_sz, 0);
+ append_operation(desc, OP_TYPE_DECAP_PROTOCOL | OP_PCLID_BLOB);
+}
+
+static void jr_jobdesc_blob_encap(u32 __iomem *desc, u8 *keymod, u8 *plain_txt,
+ u8 *blob, u16 input_size)
+{
+ dma_addr_t dma_keymod;
+ dma_addr_t dma_plain;
+ dma_addr_t dma_blob;
+ u16 in_sz;
+ u16 out_sz;
+
+ dma_keymod = (dma_addr_t)keymod;
+ dma_plain = (dma_addr_t)plain_txt;
+ dma_blob = (dma_addr_t)blob;
+
+ in_sz = input_size;
+ out_sz = input_size + BLOB_OVERHEAD;
+
+ init_job_desc(desc, 0);
+ /*
+ * The key modifier can be used to differentiate specific data.
+ * Or to prevent replay attacks.
+ */
+ append_key(desc, dma_keymod, KEYMOD_LENGTH, CLASS_2);
+ append_seq_in_ptr(desc, dma_plain, in_sz, 0);
+ append_seq_out_ptr(desc, dma_blob, out_sz, 0);
+ append_operation(desc, OP_TYPE_ENCAP_PROTOCOL | OP_PCLID_BLOB);
+}
+
+static void blob_job_done(struct device_d *dev, u32 *desc, u32 err, void *arg)
+{
+ struct blob_job_result *res = arg;
+
+ if (!res)
+ return;
+
+ if (err)
+ caam_jr_strstatus(dev, readl(0x2101044));
+
+ res->err = err;
+}
+
+/*
+ * Generate a blob with the following format:
+ * Format: Normal format (Test format only for testing)
+ * Contents: General data (aka red blob)
+ * Security State: Secure State (Non-Secure for testing)
+ * Memory Types: General memory
+ */
+static int blob_encap_blob(struct blob_priv *priv, u8 *keymod, u8 *input,
+ u8 *output, u16 input_size)
+{
+ struct device_d *jrdev = priv->jrdev;
+ struct blob_job_result testres;
+ int ret;
+
+ memset(priv->desc, 0, 64);
+
+ jr_jobdesc_blob_encap(priv->desc, keymod, input, output, input_size);
+
+ pr_debug("data:\n");
+ pr_hex_dump_debug("data: ",
+ DUMP_PREFIX_OFFSET, 16, 1, input,
+ input_size, false);
+ pr_debug("jobdesc:\n");
+ pr_hex_dump_debug("jobdesc: ",
+ DUMP_PREFIX_OFFSET, 16, 1, priv->desc,
+ desc_bytes(priv->desc), false);
+ ret = caam_jr_enqueue(jrdev, priv->desc, blob_job_done, &testres);
+
+ pr_debug("output:\n");
+ pr_hex_dump_debug("",
+ DUMP_PREFIX_OFFSET, 16, 1, priv->red_blob,
+ input_size + BLOB_OVERHEAD, false);
+
+ return ret;
+}
+
+static int blob_decap_blob(struct blob_priv *priv, u8 *keymod, u8 *input,
+ u8 *output, u16 input_length)
+{
+ struct device_d *jrdev = priv->jrdev;
+ struct blob_job_result testres;
+ int ret;
+
+ memset(priv->desc, 0, 64);
+
+ jr_jobdesc_blob_decap(priv->desc, keymod, input, output, input_length);
+
+ pr_debug("data:\n");
+ pr_hex_dump_debug("data: ",
+ DUMP_PREFIX_OFFSET, 16, 1, input,
+ input_length, false);
+ pr_debug("jobdesc:\n");
+ pr_hex_dump_debug("jobdesc: ",
+ DUMP_PREFIX_OFFSET, 16, 1, priv->desc,
+ desc_bytes(priv->desc), false);
+
+ testres.err = 0;
+ ret = caam_jr_enqueue(jrdev, priv->desc, blob_job_done, &testres);
+ if (ret) {
+ dev_err(jrdev, "decryption error\n");
+ }
+ ret = testres.err;
+
+ pr_debug("%s: input_length %d\n", __func__, input_length);
+ pr_debug("output:\n");
+ pr_hex_dump_debug("",
+ DUMP_PREFIX_OFFSET, 16, 1, output,
+ input_length - BLOB_OVERHEAD, false);
+
+ return ret;
+}
+
+static int blob_gen_payload_get(struct param_d *p, void *arg)
+{
+ struct blob_priv *priv = arg;
+ struct blob_param *payload = &priv->payload_param;
+
+ if (priv->payload_size == 0)
+ return -EINVAL;
+
+ if (priv->access != USERSPACE)
+ return -EPERM;
+
+ free(payload->value);
+ payload->value = xstrndup(priv->payload->data, priv->payload_size);
+
+ return 0;
+}
+
+static int blob_gen_payload_set(struct param_d *p, void *arg)
+{
+ struct blob_priv *priv = arg;
+ struct blob_param *payload = &priv->payload_param;
+ size_t len;
+
+ if (priv->busy)
+ return -EBUSY;
+
+ len = strlen(payload->value);
+ if (len > sizeof(priv->payload->data))
+ return -EINVAL;
+
+ memcpy(priv->payload->data, payload->value, len);
+ priv->payload_size = len;
+
+ return 0;
+}
+
+static int blob_gen_blob_set(struct param_d *p, void *arg)
+{
+ struct blob_priv *priv = arg;
+ struct blob_param *blob = &priv->blob_param;
+ int length;
+ int ret;
+
+ if (priv->busy)
+ return -EBUSY;
+
+ length = strlen(blob->value);
+ if (length <= 0) {
+ dev_err(&priv->dev, "blob can't be 0\n");
+ return -EINVAL;
+ }
+
+ priv->busy = true;
+
+ pr_debug("red_blob:\n");
+ pr_hex_dump_debug("",
+ DUMP_PREFIX_OFFSET, 16, 1, blob->value,
+ length, false);
+
+ memset(priv->red_blob->data, 0x0, sizeof(priv->red_blob->data));
+ length = decode_base64(priv->red_blob->data, sizeof(priv->red_blob->data), blob->value);
+ if (length <= BLOB_OVERHEAD) {
+ dev_err(&priv->dev, "blob to short\n");
+ priv->busy = false;
+ return -EINVAL;
+ }
+
+ pr_debug("red_blob decoded:\n");
+ pr_hex_dump_debug("",
+ DUMP_PREFIX_OFFSET, 16, 1, priv->red_blob,
+ length, false);
+
+ memset(priv->payload->data, 0x0, sizeof(priv->payload->data));
+
+ ret = blob_decap_blob(priv, priv->modifier->data, priv->red_blob->data,
+ priv->payload->data, length);
+ if (ret) {
+ priv->busy = false;
+ return -EINVAL;
+ }
+
+ priv->payload_size = length - BLOB_OVERHEAD;
+
+ priv->busy = false;
+ return 0;
+}
+
+static int blob_gen_blob_get(struct param_d *p, void *arg)
+{
+ struct blob_priv *priv = arg;
+ struct blob_param *blob = &priv->blob_param;
+ int length;
+ int ret;
+
+ if (priv->busy)
+ return -EBUSY;
+
+ if (priv->payload_size <= 0) {
+ dev_err(&priv->dev, "No payload given\n");
+ return -EINVAL;
+ }
+
+ priv->busy = true;
+
+ memset(priv->red_blob->data, 0x0, sizeof(priv->red_blob->data));
+ ret = blob_encap_blob(priv,
+ priv->modifier->data,
+ priv->payload->data,
+ priv->red_blob->data,
+ priv->payload_size);
+ if (ret) {
+ priv->busy = false;
+ return -EINVAL;
+ }
+
+ free(blob->value);
+ length = priv->payload_size + BLOB_OVERHEAD;
+ blob->value = xzalloc(BASE64_LENGTH(length) + 1);
+ uuencode(blob->value, priv->red_blob->data, length);
+
+ pr_hex_dump_debug("",
+ DUMP_PREFIX_OFFSET, 16, 1, blob->value,
+ strlen(blob->value), false);
+
+ priv->busy = false;
+
+ return 0;
+}
+
+static int blob_gen_modifier_set(struct param_d *p, void *arg)
+{
+ struct blob_priv *priv = arg;
+ struct blob_param *modifier = &priv->modifier_param;
+ ssize_t len;
+
+ if (priv->busy)
+ return -EBUSY;
+
+ if (!strncmp(modifier->value, "kernel:evm", 10))
+ priv->access = KERNEL_EVM;
+ else if (!strncmp(modifier->value, "kernel:", 7))
+ priv->access = KERNEL;
+ else if (!strncmp(modifier->value, "user:", 5))
+ priv->access = USERSPACE;
+
+ len = strlen(modifier->value);
+ if (len > sizeof(priv->modifier->data))
+ return -EINVAL;
+
+ memset(priv->modifier->data, 0, sizeof(priv->modifier->data));
+ memcpy(priv->modifier->data, modifier->value, len);
+
+ return 0;
+}
+
+static int blob_gen_probe(struct device_d *dev)
+{
+ struct device_node *dev_node;
+ struct device_d *jrdev;
+ struct blob_priv *priv;
+ int ret;
+
+ priv = xzalloc(sizeof(*priv));
+
+ priv->busy = false;
+
+ dev->priv = priv;
+
+ dev_node = of_find_compatible_node(NULL, NULL, "fsl,sec-v4.0-job-ring");
+ if (!dev_node) {
+ dev_node = of_find_compatible_node(NULL, NULL, "fsl,sec4.0-job-ring");
+ if (!dev_node)
+ return -ENODEV;
+ }
+
+ jrdev = of_find_device_by_node(dev_node);
+ if (!jrdev)
+ return -ENODEV;
+
+ priv->jrdev = jrdev;
+
+ priv->payload = dma_alloc_coherent(sizeof(*priv->payload),
+ DMA_ADDRESS_BROKEN);
+ if (!priv->payload) {
+ dev_err(dev, "unable to allocate payload\n");
+ return -ENOMEM;
+ }
+ priv->modifier = dma_alloc_coherent(sizeof(*priv->modifier),
+ DMA_ADDRESS_BROKEN);
+ if (!priv->modifier) {
+ dev_err(dev, "unable to allocate modifier\n");
+ ret = -ENOMEM;
+ goto out_payload;
+ }
+
+ priv->red_blob = dma_alloc_coherent(sizeof(*priv->red_blob),
+ DMA_ADDRESS_BROKEN);
+ if (!priv->red_blob) {
+ dev_err(dev, "unable to allocate red_blob\n");
+ ret = -ENOMEM;
+ goto out_modifier;
+ }
+
+ priv->desc = dma_alloc_coherent(sizeof(*priv->desc) * 64, DMA_ADDRESS_BROKEN);
+ if (!priv->desc) {
+ dev_err(dev, "unable to allocate desc\n");
+ ret = -ENOMEM;
+ goto out_blob;
+ }
+
+ strcpy(priv->dev.name, "blob");
+ priv->dev.parent = dev;
+ register_device(&priv->dev);
+
+ priv->modifier_param.param = dev_add_param_string(&(priv->dev), "modifier",
+ blob_gen_modifier_set,
+ NULL,
+ &priv->modifier_param.value,
+ priv);
+ if (IS_ERR(priv->modifier_param.param)) {
+ ret = PTR_ERR(&priv->modifier_param.param);
+ goto out_desc;
+ }
+
+ priv->payload_param.param = dev_add_param_string(&(priv->dev), "payload",
+ blob_gen_payload_set,
+ blob_gen_payload_get,
+ &priv->payload_param.value,
+ priv);
+ if (IS_ERR(priv->payload_param.param)) {
+ ret = PTR_ERR(&priv->payload_param.param);
+ goto out_desc;
+ }
+
+ priv->blob_param.param = dev_add_param_string(&(priv->dev), "blob",
+ blob_gen_blob_set,
+ blob_gen_blob_get,
+ &priv->blob_param.value,
+ priv);
+ if (IS_ERR(priv->blob_param.param)) {
+ ret = PTR_ERR(&priv->blob_param.param);
+ goto out_desc;
+ }
+
+ return 0;
+
+out_desc:
+ dma_free_coherent(priv->desc, 0, sizeof(*priv->desc) * 64);
+out_blob:
+ dma_free_coherent(priv->red_blob, 0, sizeof(*priv->red_blob));
+out_modifier:
+ dma_free_coherent(priv->modifier, 0, sizeof(*priv->modifier));
+out_payload:
+ dma_free_coherent(priv->payload, 0, sizeof(*priv->payload));
+ return ret;
+}
+
+static struct of_device_id blob_gen_ids[] = {
+ {
+ .compatible = "caam_blob",
+ },
+ {},
+};
+
+static struct driver_d blob_gen_driver = {
+ .name = DRIVERNAME,
+ .of_compatible = DRV_OF_COMPAT(blob_gen_ids),
+ .probe = blob_gen_probe,
+};
+device_platform_driver(blob_gen_driver);
--
2.6.1
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