[PATCH] tpm: reorganize sysfs files

Many of the sysfs files were calling the TPM_GetCapability command with array.
Since for 1.2 more sysfs files of this type are coming I am generalizing the
array so there can be one array and the unique parts can be filled in just
before the command is called.

Signed-off-by: Kylene Hall <kjhall@us.ibm.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c
index 379c5d465579e51d140a37f643d03070877226db..187bcdaf7bf646b625809ab44819abc20bed9a57 100644 (file)
--- a/drivers/char/tpm/tpm.c
+++ b/drivers/char/tpm/tpm.c
@@ -119,17 +119,57 @@ out:
 }
 
 #define TPM_DIGEST_SIZE 20
-#define CAP_PCR_RESULT_SIZE 18
-static const u8 cap_pcr[] = {
+#define TPM_ERROR_SIZE 10
+#define TPM_RET_CODE_IDX 6
+#define TPM_GET_CAP_RET_SIZE_IDX 10
+#define TPM_GET_CAP_RET_UINT32_1_IDX 14
+#define TPM_GET_CAP_RET_UINT32_2_IDX 18
+#define TPM_GET_CAP_RET_UINT32_3_IDX 22
+#define TPM_GET_CAP_RET_UINT32_4_IDX 26
+
+#define TPM_CAP_IDX 13
+#define TPM_CAP_SUBCAP_IDX 21
+
+enum tpm_capabilities {
+       TPM_CAP_PROP = 5,
+};
+
+enum tpm_sub_capabilities {
+       TPM_CAP_PROP_PCR = 0x1,
+       TPM_CAP_PROP_MANUFACTURER = 0x3,
+};
+
+/*
+ * This is a semi generic GetCapability command for use
+ * with the capability type TPM_CAP_PROP or TPM_CAP_FLAG
+ * and their associated sub_capabilities.
+ */
+
+static const u8 tpm_cap[] = {
        0, 193,                 /* TPM_TAG_RQU_COMMAND */
        0, 0, 0, 22,            /* length */
        0, 0, 0, 101,           /* TPM_ORD_GetCapability */
-       0, 0, 0, 5,
-       0, 0, 0, 4,
-       0, 0, 1, 1
+       0, 0, 0, 0,             /* TPM_CAP_<TYPE> */
+       0, 0, 0, 4,             /* TPM_CAP_SUB_<TYPE> size */
+       0, 0, 1, 0              /* TPM_CAP_SUB_<TYPE> */
 };
 
-#define READ_PCR_RESULT_SIZE 30
+static ssize_t transmit_cmd(struct tpm_chip *chip, u8 *data, int len,
+                           char *desc)
+{
+       int err;
+
+       len = tpm_transmit(chip, data, len);
+       if (len <  0)
+               return len;
+       if (len == TPM_ERROR_SIZE) {
+               err = be32_to_cpu(*((__be32 *) (data + TPM_RET_CODE_IDX)));
+               dev_dbg(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
+               return err;
+       }
+       return 0;
+}
+
 static const u8 pcrread[] = {
        0, 193,                 /* TPM_TAG_RQU_COMMAND */
        0, 0, 0, 14,            /* length */
@@ -140,8 +180,8 @@ static const u8 pcrread[] = {
 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
                      char *buf)
 {
-       u8 data[READ_PCR_RESULT_SIZE];
-       ssize_t len;
+       u8 data[30];
+       ssize_t rc;
        int i, j, num_pcrs;
        __be32 index;
        char *str = buf;
@@ -150,29 +190,24 @@ ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
        if (chip == NULL)
                return -ENODEV;
 
-       memcpy(data, cap_pcr, sizeof(cap_pcr));
-       if ((len = tpm_transmit(chip, data, sizeof(data)))
-           < CAP_PCR_RESULT_SIZE) {
-               dev_dbg(chip->dev, "A TPM error (%d) occurred "
-                               "attempting to determine the number of PCRS\n",
-                       be32_to_cpu(*((__be32 *) (data + 6))));
+       memcpy(data, tpm_cap, sizeof(tpm_cap));
+       data[TPM_CAP_IDX] = TPM_CAP_PROP;
+       data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_PCR;
+
+       rc = transmit_cmd(chip, data, sizeof(data),
+                       "attempting to determine the number of PCRS");
+       if (rc)
                return 0;
-       }
 
        num_pcrs = be32_to_cpu(*((__be32 *) (data + 14)));
-
        for (i = 0; i < num_pcrs; i++) {
                memcpy(data, pcrread, sizeof(pcrread));
                index = cpu_to_be32(i);
                memcpy(data + 10, &index, 4);
-               if ((len = tpm_transmit(chip, data, sizeof(data)))
-                   < READ_PCR_RESULT_SIZE){
-                       dev_dbg(chip->dev, "A TPM error (%d) occurred"
-                               " attempting to read PCR %d of %d\n",
-                               be32_to_cpu(*((__be32 *) (data + 6))),
-                               i, num_pcrs);
+               rc = transmit_cmd(chip, data, sizeof(data),
+                               "attempting to read a PCR");
+               if (rc)
                        goto out;
-               }
                str += sprintf(str, "PCR-%02d: ", i);
                for (j = 0; j < TPM_DIGEST_SIZE; j++)
                        str += sprintf(str, "%02X ", *(data + 10 + j));
@@ -194,7 +229,7 @@ ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
                       char *buf)
 {
        u8 *data;
-       ssize_t len;
+       ssize_t err;
        int i, rc;
        char *str = buf;
 
@@ -208,14 +243,10 @@ ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
 
        memcpy(data, readpubek, sizeof(readpubek));
 
-       if ((len = tpm_transmit(chip, data, READ_PUBEK_RESULT_SIZE)) <
-           READ_PUBEK_RESULT_SIZE) {
-               dev_dbg(chip->dev, "A TPM error (%d) occurred "
-                               "attempting to read the PUBEK\n",
-                           be32_to_cpu(*((__be32 *) (data + 6))));
-               rc = 0;
+       err = transmit_cmd(chip, data, READ_PUBEK_RESULT_SIZE,
+                       "attempting to read the PUBEK");
+       if (err)
                goto out;
-       }
 
        /* 
           ignore header 10 bytes
@@ -245,63 +276,59 @@ ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
                if ((i + 1) % 16 == 0)
                        str += sprintf(str, "\n");
        }
-       rc = str - buf;
 out:
+       rc = str - buf;
        kfree(data);
        return rc;
 }
 EXPORT_SYMBOL_GPL(tpm_show_pubek);
 
-#define CAP_VER_RESULT_SIZE 18
+#define CAP_VERSION_1_1 6
+#define CAP_VERSION_IDX 13
 static const u8 cap_version[] = {
        0, 193,                 /* TPM_TAG_RQU_COMMAND */
        0, 0, 0, 18,            /* length */
        0, 0, 0, 101,           /* TPM_ORD_GetCapability */
-       0, 0, 0, 6,
+       0, 0, 0, 0,
        0, 0, 0, 0
 };
 
-#define CAP_MANUFACTURER_RESULT_SIZE 18
-static const u8 cap_manufacturer[] = {
-       0, 193,                 /* TPM_TAG_RQU_COMMAND */
-       0, 0, 0, 22,            /* length */
-       0, 0, 0, 101,           /* TPM_ORD_GetCapability */
-       0, 0, 0, 5,
-       0, 0, 0, 4,
-       0, 0, 1, 3
-};
-
 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
                      char *buf)
 {
-       u8 data[sizeof(cap_manufacturer)];
-       ssize_t len;
+       u8 data[30];
+       ssize_t rc;
        char *str = buf;
 
        struct tpm_chip *chip = dev_get_drvdata(dev);
        if (chip == NULL)
                return -ENODEV;
 
-       memcpy(data, cap_manufacturer, sizeof(cap_manufacturer));
+       memcpy(data, tpm_cap, sizeof(tpm_cap));
+       data[TPM_CAP_IDX] = TPM_CAP_PROP;
+       data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_MANUFACTURER;
 
-       if ((len = tpm_transmit(chip, data, sizeof(data))) <
-           CAP_MANUFACTURER_RESULT_SIZE)
-               return len;
+       rc = transmit_cmd(chip, data, sizeof(data),
+                       "attempting to determine the manufacturer");
+       if (rc)
+               return 0;
 
        str += sprintf(str, "Manufacturer: 0x%x\n",
-                      be32_to_cpu(*((__be32 *) (data + 14))));
+                      be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_1_IDX))));
 
        memcpy(data, cap_version, sizeof(cap_version));
+       data[CAP_VERSION_IDX] = CAP_VERSION_1_1;
+       rc = transmit_cmd(chip, data, sizeof(data),
+                       "attempting to determine the 1.1 version");
+       if (rc)
+               goto out;
 
-       if ((len = tpm_transmit(chip, data, sizeof(data))) <
-           CAP_VER_RESULT_SIZE)
-               return len;
-
-       str +=
-           sprintf(str, "TCG version: %d.%d\nFirmware version: %d.%d\n",
-                   (int) data[14], (int) data[15], (int) data[16],
-                   (int) data[17]);
+       str += sprintf(str,
+                      "TCG version: %d.%d\nFirmware version: %d.%d\n",
+                      (int) data[14], (int) data[15], (int) data[16],
+                      (int) data[17]);
 
+out:
        return str - buf;
 }
 EXPORT_SYMBOL_GPL(tpm_show_caps);