Define a log_errno_reset macro to emit the errno string at or near the
time of error, similar to the existing log_errno macro, but also reset
errno to avoid dangling or duplicate errno messages on exit.
The initial usage is for non-critical file open failures.
Suggested-by: Vitaly Chikunov <vt@xxxxxxxxxxxx>
Signed-off-by: Mimi Zohar <zohar@xxxxxxxxxxxxx>
---
src/evmctl.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/src/evmctl.c b/src/evmctl.c
index 0412bc0ac2b0..54123bf20f03 100644
--- a/src/evmctl.c
+++ b/src/evmctl.c
@@ -166,6 +166,9 @@ struct tpm_bank_info {
static char *pcrfile[MAX_PCRFILE];
static unsigned npcrfile;
+#define log_errno_reset(level, fmt, args...) \
+ {do_log(level, fmt " (errno: %s)\n", ##args, strerror(errno)); errno = 0; }
+
static int bin2file(const char *file, const char *ext, const unsigned char *data, int len)
{
FILE *fp;
@@ -1911,8 +1914,10 @@ static int read_sysfs_pcrs(int num_banks, struct tpm_bank_info *tpm_banks)
fp = fopen(pcrs, "r");
if (!fp)
fp = fopen(misc_pcrs, "r");
- if (!fp)
+ if (!fp) {
+ log_errno_reset(LOG_DEBUG, "Failed to read TPM 1.2 PCRs");
return -1;
+ }
result = read_one_bank(&tpm_banks[0], fp);
fclose(fp);
@@ -2055,7 +2060,6 @@ static int ima_measurement(const char *file)
int err_padded = -1;
int err = -1;
- errno = 0;
memset(zero, 0, MAX_DIGEST_SIZE);
pseudo_padded_banks = init_tpm_banks(&num_banks);
@@ -2072,6 +2076,8 @@ static int ima_measurement(const char *file)
init_public_keys(imaevm_params.keyfile);
else /* assume read pubkey from x509 cert */
init_public_keys("/etc/keys/x509_evm.der");
+ if (errno)
+ log_errno_reset(LOG_DEBUG, "Failed to initialize public keys");
/*
* Reading the PCRs before walking the IMA measurement list
@@ -2746,6 +2752,8 @@ int main(int argc, char *argv[])
unsigned long keyid;
char *eptr;
+ errno = 0; /* initialize global errno */
+
#if !(OPENSSL_VERSION_NUMBER < 0x10100000)
OPENSSL_init_crypto(
#ifndef DISABLE_OPENSSL_CONF
--
2.31.1
