[PATCH v2 8/8] tpm: move tpm2 code validation to tpm2-space.c

[Tomas Winkler]

Add new function tpm2_validate_command to tpm2-space.c
that wraps up open coded functionality from tpm_validate_command.

Signed-off-by: Tomas Winkler <tomas.wink...@intel.com>
---
 drivers/char/tpm/tpm-interface.c | 31 ++-----------------------------
 drivers/char/tpm/tpm.h           |  1 +
 drivers/char/tpm/tpm2-cmd.c      |  1 +
 drivers/char/tpm/tpm2-space.c    | 32 ++++++++++++++++++++++++++++++++
 4 files changed, 36 insertions(+), 29 deletions(-)

diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index d347ad8325c6..93f7c12d4c4d 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -52,40 +52,13 @@ static int tpm_validate_command(struct tpm_chip *chip,
                                 const u8 *cmd,
                                 size_t len)
 {
-       const struct tpm_input_header *header = (const void *)cmd;
-       int i;
-       u32 cc;
-       u32 attrs;
-       unsigned int nr_handles;
-
        if (len < TPM_HEADER_SIZE)
                return -EINVAL;
 
-       if (!space)
-               return 0;
-
-       if (chip->flags & TPM_CHIP_FLAG_TPM2 && chip->nr_commands) {
-               cc = be32_to_cpu(header->ordinal);
-
-               i = tpm2_find_cc(chip, cc);
-               if (i < 0) {
-                       dev_dbg(&chip->dev, "0x%04X is an invalid command\n",
-                               cc);
-                       return -EOPNOTSUPP;
-               }
-
-               attrs = chip->cc_attrs_tbl[i];
-               nr_handles =
-                       4 * ((attrs >> TPM2_CC_ATTR_CHANDLES) & GENMASK(2, 0));
-               if (len < TPM_HEADER_SIZE + 4 * nr_handles)
-                       goto err_len;
-       }
+       if (chip->flags & TPM_CHIP_FLAG_TPM2 && space)
+               return tpm2_validate_command(chip, cmd, len);
 
        return 0;
-err_len:
-       dev_dbg(&chip->dev,
-               "%s: insufficient command length %zu", __func__, len);
-       return -EINVAL;
 }
 
 static int tpm_request_locality(struct tpm_chip *chip)
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 2b88aadc4743..15453a78a0d0 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -602,6 +602,7 @@ int tpm2_prepare_space(struct tpm_chip *chip, struct 
tpm_space *space, u32 cc,
                       u8 *cmd);
 int tpm2_commit_space(struct tpm_chip *chip, struct tpm_space *space,
                      u32 cc, u8 *buf, size_t *bufsiz);
+int tpm2_validate_command(struct tpm_chip *chip, const u8 *cmd, size_t len);
 
 extern const struct seq_operations tpm2_binary_b_measurements_seqops;
 
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 80eb4bb5feef..6db13cf801b4 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -1112,3 +1112,4 @@ int tpm2_find_cc(struct tpm_chip *chip, u32 cc)
 
        return -1;
 }
+
diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c
index 4e4014eabdb9..ed9eff948c05 100644
--- a/drivers/char/tpm/tpm2-space.c
+++ b/drivers/char/tpm/tpm2-space.c
@@ -263,6 +263,38 @@ static int tpm2_map_command(struct tpm_chip *chip, u32 cc, 
u8 *cmd)
        return 0;
 }
 
+int tpm2_validate_command(struct tpm_chip *chip, const u8 *cmd, size_t len)
+{
+       int i;
+       u32 cc;
+       u32 attrs;
+       unsigned int nr_handles;
+
+       if (len < TPM_HEADER_SIZE)
+               return -EINVAL;
+
+       if (!chip->nr_commands)
+               return 0;
+
+       cc =  be32_to_cpup((__be32 *)(cmd + 6));
+
+       i = tpm2_find_cc(chip, cc);
+       if (i < 0) {
+               dev_dbg(&chip->dev, "0x%04X is an invalid command\n", cc);
+               return -EOPNOTSUPP;
+       }
+
+       attrs = chip->cc_attrs_tbl[i];
+       nr_handles = 4 * ((attrs >> TPM2_CC_ATTR_CHANDLES) & GENMASK(2, 0));
+       if (len < TPM_HEADER_SIZE + 4 * nr_handles) {
+               dev_dbg(&chip->dev,
+                       "%s: insufficient command length %zu", __func__, len);
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
 int tpm2_prepare_space(struct tpm_chip *chip, struct tpm_space *space, u32 cc,
                       u8 *cmd)
 {
-- 
2.14.3