Bruno,

On Thu, Aug 19, 2021 at 03:28:17PM -0300, Bruno Meneguele wrote:

On Thu, Aug 19, 2021 at 05:11:36AM +0300, Vitaly Chikunov wrote:

quoted

After CRYPTO_secure_malloc_init OpenSSL will store private keys in
secure heap. This facility is only available since OpenSSL_1_1_0-pre1.

Signed-off-by: Vitaly Chikunov <redacted>
---
Change from v1:
- Do not use setfbuf to disable buffering as this is not proven to be
  meaningful.
- Use secure heap for passwords too as suggested by Mimi Zohar.
- Fallback to OPENSSL_malloc for old OpenSSL as suggested by Mimi Zohar.
- Simplify logic of calling CRYPTO_secure_malloc_init (call it always on
  OpenSSL init.)
- Should be applied after Bruno Meneguele's "evmctl: fix memory leak in
  get_password" patch v2.

 src/evmctl.c | 143 ++++++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 118 insertions(+), 25 deletions(-)

diff --git a/src/evmctl.c b/src/evmctl.c
index 5f7c2b8..a27e0b9 100644
--- a/src/evmctl.c
+++ b/src/evmctl.c

@@ -59,6 +59,7 @@
 #include <assert.h>
 
 #include <openssl/asn1.h>
+#include <openssl/crypto.h>
 #include <openssl/sha.h>
 #include <openssl/pem.h>
 #include <openssl/hmac.h>

@@ -165,6 +166,24 @@ struct tpm_bank_info {
 static char *pcrfile[MAX_PCRFILE];
 static unsigned npcrfile;
 
+#if OPENSSL_VERSION_NUMBER <= 0x10100000
+#warning Your OpenSSL version is too old to have OPENSSL_secure_malloc, \
+	falling back to use plain OPENSSL_malloc.
+#define OPENSSL_secure_malloc	  OPENSSL_malloc
+#define OPENSSL_secure_free	  OPENSSL_free
+/*
+ * Secure heap memory automatically cleared on free, but
+ * OPENSSL_secure_clear_free will be used in case of fallback

Shouldn't it be OPENSSL_clear_free instead of OPENSLL_secure_clear_free
in the setence above?

No. I meant our code will use OPENSSL_secure_clear_free, so when there
is no secure heap it will fallback to OPENSSL_clear_free (and not just
to OPENSSL_free if we used OPENSSL_secure_free).

Thanks,

-- 
bmeneg 
PGP Key: http://bmeneg.com/pubkey.txt