PCR numbers are naturally unsigned values. Further, they are
32 bits, even on 64-bit machines. This change eliminates the
need for negative value and overflow tests.
The parameter name is changed from j and idx to pcr_handle, which is
more descriptive and is similar to the parameter name used in the TPM
2.0 specification.
Signed-off-by: Ken Goldman <kgoldman@xxxxxxxxxx>
---
src/evmctl.c | 12 ++++++++----
src/pcr.h | 2 +-
src/pcr_tss.c | 5 +++--
src/pcr_tsspcrread.c | 6 +++---
4 files changed, 15 insertions(+), 10 deletions(-)
diff --git a/src/evmctl.c b/src/evmctl.c
index a8065bb..c999589 100644
--- a/src/evmctl.c
+++ b/src/evmctl.c
@@ -1914,7 +1914,8 @@ static int read_tpm_banks(int num_banks, struct tpm_bank_info *bank)
{
int tpm_enabled = 0;
char *errmsg = NULL;
- int i, j;
+ int i;
+ uint32_t pcr_handle;
int err;
/* If --pcrs was specified, read only from the specified file(s) */
@@ -1934,9 +1935,12 @@ static int read_tpm_banks(int num_banks, struct tpm_bank_info *bank)
/* Read PCRs from multiple TPM 2.0 banks */
for (i = 0; i < num_banks; i++) {
err = 0;
- for (j = 0; j < NUM_PCRS && !err; j++) {
- err = tpm2_pcr_read(bank[i].algo_name, j,
- bank[i].pcr[j], bank[i].digest_size,
+ for (pcr_handle = 0;
+ pcr_handle < NUM_PCRS && !err;
+ pcr_handle++) {
+ err = tpm2_pcr_read(bank[i].algo_name, pcr_handle,
+ bank[i].pcr[pcr_handle],
+ bank[i].digest_size,
&errmsg);
if (err) {
log_debug("Failed to read %s PCRs: (%s)\n",
diff --git a/src/pcr.h b/src/pcr.h
index 79547bd..205bae8 100644
--- a/src/pcr.h
+++ b/src/pcr.h
@@ -1,3 +1,3 @@
int tpm2_pcr_supported(void);
-int tpm2_pcr_read(const char *algo_name, int idx, uint8_t *hwpcr,
+int tpm2_pcr_read(const char *algo_name, uint32_t pcr_handle, uint8_t *hwpcr,
int len, char **errmsg);
diff --git a/src/pcr_tss.c b/src/pcr_tss.c
index feb1ff7..10930e2 100644
--- a/src/pcr_tss.c
+++ b/src/pcr_tss.c
@@ -106,7 +106,7 @@ static TPM2_ALG_ID algo_to_tss2(const char *algo_name)
return TPM2_ALG_ERROR;
}
-int tpm2_pcr_read(const char *algo_name, int idx, uint8_t *hwpcr,
+int tpm2_pcr_read(const char *algo_name, uint32_t pcr_handle, uint8_t *hwpcr,
int len, char **errmsg)
{
TSS2_ABI_VERSION abi_version = {
@@ -140,7 +140,8 @@ int tpm2_pcr_read(const char *algo_name, int idx, uint8_t *hwpcr,
}
};
- pcr_select_in.pcrSelections[0].pcrSelect[idx / 8] = (1 << (idx % 8));
+ pcr_select_in.pcrSelections[0].pcrSelect[pcr_handle / 8] =
+ (1 << (pcr_handle % 8));
ret = Esys_Initialize(&ctx, NULL, &abi_version);
if (ret != TPM2_RC_SUCCESS) {
diff --git a/src/pcr_tsspcrread.c b/src/pcr_tsspcrread.c
index 183dfc2..95048f8 100644
--- a/src/pcr_tsspcrread.c
+++ b/src/pcr_tsspcrread.c
@@ -68,7 +68,7 @@ int tpm2_pcr_supported(void)
return 1;
}
-int tpm2_pcr_read(const char *algo_name, int idx, uint8_t *hwpcr,
+int tpm2_pcr_read(const char *algo_name, uint32_t pcr_handle, uint8_t *hwpcr,
int len, char **errmsg)
{
FILE *fp;
@@ -76,8 +76,8 @@ int tpm2_pcr_read(const char *algo_name, int idx, uint8_t *hwpcr,
char cmd[PATH_MAX + 50];
int ret;
- sprintf(cmd, "%s -halg %s -ha %d -ns 2> /dev/null",
- path, algo_name, idx);
+ sprintf(cmd, "%s -halg %s -ha %u -ns 2> /dev/null",
+ path, algo_name, pcr_handle);
fp = popen(cmd, "r");
if (!fp) {
ret = asprintf(errmsg, "popen failed: %s", strerror(errno));
--
2.25.1
