@@ -5,6 +5,7 @@
* Copyright (C) 2019, 2024 Marek Behún <kabel@kernel.org>
*/
+#include <crypto/sha2.h>
#include <linux/armada-37xx-rwtm-mailbox.h>
#include <linux/completion.h>
#include <linux/debugfs.h>
@@ -27,6 +28,12 @@
* https://gitlab.labs.nic.cz/turris/mox-boot-builder/tree/master/wtmi.
*/
+#define MOX_ECC_NUMBER_WORDS 17
+#define MOX_ECC_NUMBER_LEN (MOX_ECC_NUMBER_WORDS * sizeof(u32))
+
+#define MOX_ECC_SIGNATURE_WORDS (2 * MOX_ECC_NUMBER_WORDS)
+#define MOX_ECC_SIGNATURE_LEN (MOX_ECC_NUMBER_WORDS * sizeof(u32))
+
#define MBOX_STS_SUCCESS (0 << 30)
#define MBOX_STS_FAIL (1 << 30)
#define MBOX_STS_BADCMD (2 << 30)
@@ -81,7 +88,7 @@ struct mox_rwtm {
* from userspace.
*/
struct dentry *debugfs_root;
- u32 last_sig[34];
+ u32 last_sig[MOX_ECC_SIGNATURE_WORDS];
bool last_sig_done;
#endif
};
@@ -342,14 +349,15 @@ static ssize_t do_sign_read(struct file *file, char __user *buf, size_t len,
if (*ppos != 0)
return 0;
- if (len < 136)
+ if (len < MOX_ECC_SIGNATURE_LEN)
return -EINVAL;
if (!rwtm->last_sig_done)
return -ENODATA;
/* 2 arrays of 17 32-bit words are 136 bytes */
- ret = simple_read_from_buffer(buf, len, ppos, rwtm->last_sig, 136);
+ ret = simple_read_from_buffer(buf, len, ppos, rwtm->last_sig,
+ MOX_ECC_SIGNATURE_LEN);
rwtm->last_sig_done = false;
return ret;
@@ -364,8 +372,7 @@ static ssize_t do_sign_write(struct file *file, const char __user *buf,
loff_t dummy = 0;
ssize_t ret;
- /* the input is a SHA-512 hash, so exactly 64 bytes have to be read */
- if (len != 64)
+ if (len != SHA512_DIGEST_SIZE)
return -EINVAL;
/* if last result is not zero user has not read that information yet */
@@ -386,17 +393,18 @@ static ssize_t do_sign_write(struct file *file, const char __user *buf,
* 3. Address of the buffer where ECDSA signature value S shall be
* stored by the rWTM firmware.
*/
- memset(rwtm->buf, 0, 4);
- ret = simple_write_to_buffer(rwtm->buf + 4, 64, &dummy, buf, len);
+ memset(rwtm->buf, 0, sizeof(u32));
+ ret = simple_write_to_buffer(rwtm->buf + sizeof(u32),
+ SHA512_DIGEST_SIZE, &dummy, buf, len);
if (ret < 0)
goto unlock_mutex;
- be32_to_cpu_array(rwtm->buf, rwtm->buf, 17);
+ be32_to_cpu_array(rwtm->buf, rwtm->buf, MOX_ECC_NUMBER_WORDS);
msg.command = MBOX_CMD_SIGN;
msg.args[0] = 1;
msg.args[1] = rwtm->buf_phys;
- msg.args[2] = rwtm->buf_phys + 68;
- msg.args[3] = rwtm->buf_phys + 2 * 68;
+ msg.args[2] = rwtm->buf_phys + MOX_ECC_NUMBER_LEN;
+ msg.args[3] = rwtm->buf_phys + 2 * MOX_ECC_NUMBER_LEN;
ret = mbox_send_message(rwtm->mbox, &msg);
if (ret < 0)
goto unlock_mutex;
@@ -414,8 +422,10 @@ static ssize_t do_sign_write(struct file *file, const char __user *buf,
* computed by the rWTM firmware and convert their words from
* LE to BE.
*/
- memcpy(rwtm->last_sig, rwtm->buf + 68, 136);
- cpu_to_be32_array(rwtm->last_sig, rwtm->last_sig, 34);
+ memcpy(rwtm->last_sig, rwtm->buf + MOX_ECC_NUMBER_LEN,
+ MOX_ECC_SIGNATURE_LEN);
+ cpu_to_be32_array(rwtm->last_sig, rwtm->last_sig,
+ MOX_ECC_SIGNATURE_WORDS);
rwtm->last_sig_done = true;
mutex_unlock(&rwtm->busy);
Hide signature generation related constants behind macros instead of hardcoding the values. Use SHA512_DIGEST_SIZE from crypto/sha2.h instead of hardcoded 64 as the message size. Signed-off-by: Marek Behún <kabel@kernel.org> --- drivers/firmware/turris-mox-rwtm.c | 34 +++++++++++++++++++----------- 1 file changed, 22 insertions(+), 12 deletions(-)