1 files changed, 64 insertions, 10 deletions

diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c
index 3af9f4d1a23f..f26afdb1a702 100644
--- a/drivers/char/tpm/tpm.c
+++ b/drivers/char/tpm/tpm.c
@@ -30,12 +30,7 @@
 #include <linux/freezer.h>
 
 #include "tpm.h"
-
-enum tpm_const {
-        TPM_MINOR = 224,        /* officially assigned */
-        TPM_BUFSIZE = 4096,
-        TPM_NUM_DEVICES = 256,
-};
+#include "tpm_eventlog.h"
 
 enum tpm_duration {
         TPM_SHORT = 0,
@@ -482,6 +477,7 @@ static ssize_t transmit_cmd(struct tpm_chip *chip, struct tpm_cmd_t *cmd,
 #define TPM_INTERNAL_RESULT_SIZE 200
 #define TPM_TAG_RQU_COMMAND cpu_to_be16(193)
 #define TPM_ORD_GET_CAP cpu_to_be32(101)
+#define TPM_ORD_GET_RANDOM cpu_to_be32(70)
 
 static const struct tpm_input_header tpm_getcap_header = {
         .tag = TPM_TAG_RQU_COMMAND,
@@ -919,7 +915,7 @@ EXPORT_SYMBOL_GPL(tpm_show_pcrs);
 
 #define  READ_PUBEK_RESULT_SIZE 314
 #define TPM_ORD_READPUBEK cpu_to_be32(124)
-struct tpm_input_header tpm_readpubek_header = {
+static struct tpm_input_header tpm_readpubek_header = {
         .tag = TPM_TAG_RQU_COMMAND,
         .length = cpu_to_be32(30),
         .ordinal = TPM_ORD_READPUBEK
@@ -1175,7 +1171,7 @@ int tpm_release(struct inode *inode, struct file *file)
         flush_work(&chip->work);
         file->private_data = NULL;
         atomic_set(&chip->data_pending, 0);
-        kfree(chip->data_buffer);
+        kzfree(chip->data_buffer);
         clear_bit(0, &chip->is_open);
         put_device(chip->dev);
         return 0;
@@ -1227,7 +1223,6 @@ ssize_t tpm_read(struct file *file, char __user *buf,
         del_singleshot_timer_sync(&chip->user_read_timer);
         flush_work(&chip->work);
         ret_size = atomic_read(&chip->data_pending);
-        atomic_set(&chip->data_pending, 0);
         if (ret_size > 0) {     /* relay data */
                 ssize_t orig_ret_size = ret_size;
                 if (size < ret_size)
@@ -1242,6 +1237,8 @@ ssize_t tpm_read(struct file *file, char __user *buf,
                 mutex_unlock(&chip->buffer_mutex);
         }
 
+        atomic_set(&chip->data_pending, 0);
+
         return ret_size;
 }
 EXPORT_SYMBOL_GPL(tpm_read);
@@ -1326,6 +1323,58 @@ int tpm_pm_resume(struct device *dev)
 }
 EXPORT_SYMBOL_GPL(tpm_pm_resume);
 
+#define TPM_GETRANDOM_RESULT_SIZE       18
+static struct tpm_input_header tpm_getrandom_header = {
+        .tag = TPM_TAG_RQU_COMMAND,
+        .length = cpu_to_be32(14),
+        .ordinal = TPM_ORD_GET_RANDOM
+};
+
+/**
+ * tpm_get_random() - Get random bytes from the tpm's RNG
+ * @chip_num: A specific chip number for the request or TPM_ANY_NUM
+ * @out: destination buffer for the random bytes
+ * @max: the max number of bytes to write to @out
+ *
+ * Returns < 0 on error and the number of bytes read on success
+ */
+int tpm_get_random(u32 chip_num, u8 *out, size_t max)
+{
+        struct tpm_chip *chip;
+        struct tpm_cmd_t tpm_cmd;
+        u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA);
+        int err, total = 0, retries = 5;
+        u8 *dest = out;
+
+        chip = tpm_chip_find_get(chip_num);
+        if (chip == NULL)
+                return -ENODEV;
+
+        if (!out || !num_bytes || max > TPM_MAX_RNG_DATA)
+                return -EINVAL;
+
+        do {
+                tpm_cmd.header.in = tpm_getrandom_header;
+                tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes);
+
+                err = transmit_cmd(chip, &tpm_cmd,
+                                   TPM_GETRANDOM_RESULT_SIZE + num_bytes,
+                                   "attempting get random");
+                if (err)
+                        break;
+
+                recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len);
+                memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd);
+
+                dest += recd;
+                total += recd;
+                num_bytes -= recd;
+        } while (retries-- && total < max);
+
+        return total ? total : -EIO;
+}
+EXPORT_SYMBOL_GPL(tpm_get_random);
+
 /* In case vendor provided release function, call it too.*/
 
 void tpm_dev_vendor_release(struct tpm_chip *chip)
@@ -1346,7 +1395,7 @@ EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
  * Once all references to platform device are down to 0,
  * release all allocated structures.
  */
-void tpm_dev_release(struct device *dev)
+static void tpm_dev_release(struct device *dev)
 {
         struct tpm_chip *chip = dev_get_drvdata(dev);
 
@@ -1427,6 +1476,11 @@ struct tpm_chip *tpm_register_hardware(struct device *dev,
                 goto put_device;
         }
 
+        if (sys_add_ppi(&dev->kobj)) {
+                misc_deregister(&chip->vendor.miscdev);
+                goto put_device;
+        }
+
         chip->bios_dir = tpm_bios_log_setup(devname);
 
         /* Make chip available */