Hi crmoratelli,

Which version of wolfSSL are you using? You can find it noted in wolfssl/version.h.

Can you try connecting to your https server using the following and send back the results?
openssl s_client -host [your host] -port [your port] -showcerts

For the wolfCrypt test I was not able to reproduce with the latest in master. But curious if changing your test so out and plain are sized as 128 and let me know your results:
byte   out[128];
byte   plain[128];

Also in the test try changing "ret = wc_InitRsaKey_ex(&key, HEAP_HINT, devId);" to use "ret = wc_InitRsaKey(&key);".

If you want to send an email to support@wolfssl.com with your https server host/port so we can test against it that would be wonderful.

Thanks,
David Garske, wolfSSL

Hi Zine314,

It looks like the AES CCM* (star) spec adds variable length auth tags plus some encoding info. We do support the normal AES CCM block cipher, which AES CCM* is backwards compatibility with, but we do not support CCM*.

I put this on our feature request list. We do offer consulting services to help expedite features. If you would like more info on this option please email us at info@wolfssl.com.

Thanks,
David Garske, wolfSSL

1. It depends on your architecture and where it puts the stack region, but technically if a stack value is used and isn't cleared then it has the potential to be available later. That is why we use ForceZero on any private data after we are done with it.

2. Only the private (sensitive) information is cleared with ForceZero and that is always enabled. We don not have an option to clear all stack variables, but you could change the mp_clear to do a ForceZero and it would clear the dp section of the big integers. Also there is a GCC compiler option in the works for clearing stack. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69976

3. It depends on the math implementation used. We have a "normal" math and "fast" math (USE_FAST_MATH). The fast math uses stack and the normal math uses heap. So only the normal math uses dynamic mem (heap) for the big integer data.

Let me know if you have any other questions,
David Garske, wolfSSL

Hi, it sounds like you are looking for a way to clear allocated buffer with zero's on the free? If you are overriding the allocators for wolfSSL then you could do something like this:

void* my_Malloc(size_t size)
{
    void* ptr;
    ptr = malloc(size + sizeof(size_t));
    if (ptr) {
        *(size_t*)ptr = size;
        ptr += sizeof(size_t);

        memset(ptr, 0, size);
    }
    return ptr;

}
void my_Free(void *ptr)
{
    if (ptr) {
        size_t size = 0;
        ptr -= sizeof(size_t);
        size = *(size_t*)ptr;
        memset(ptr, 0, size);
        free(ptr);
    }
}

wolfSSL_SetAllocators(my_Malloc, my_Free, NULL);

This allocates some extra space at the front and stores the length in it. Let me know if that makes sense or not.

Thanks,
David Garske, wolfSSL

Hi Cxdinter,

Correct, those are the porting options. Its difficult for me to guess, which is better for you and the Poco library without a more detailed review.

For the first option you may have to implement some additional openssl compatibility API's. They have over 4000 API's and we only cover the most common ones. If you do add some and would like to contribute changes back to us that would be wonderful. We only require a signed contributor agreement, which I can send you.

We have more examples in this repo:
https://github.com/wolfSSL/wolfssl-examples

Some clean TLS examples are in this folder:
https://github.com/wolfSSL/wolfssl-exam … master/tls

Thanks,
David Garske, wolfSSL

Hi Cxdinter,

We are continually working to add new openssl compatibility API's. You'll find the ones you are missing in the pull request #618, which should make it into master shortly.

https://github.com/wolfSSL/wolfssl/pull/618

SSL_CTX_ctrl:
https://github.com/wolfSSL/wolfssl/pull … 2c5b9R5625

SSL_ctrl:
https://github.com/wolfSSL/wolfssl/pull … 2c5b9R5614

We also just added a bunch on Nov 10th in PR #617 into master:
https://github.com/wolfSSL/wolfssl/pull/617
Commit: https://github.com/wolfSSL/wolfssl/comm … 4537f5279f

Hopefully that will help with the Poco port you are working on. Let us know if there is anything else.
Your feedback has been very excellent, so thank you!

David Garske, wolfSSL

Hi Cxdinter,

The underlying math used for our Ed/Curve implementation is not the same and is highly optimized for that curve. That is the reason Ed/Curve 25519 is not in the ecc_sets table. However I think it would be good to have it in there optionally for those who want to keep the code size down. I'm adding it to our feature list. Thanks for the idea and your reports. Let me know if there is anything else.

Thanks,
David Garske, wolfSSL

Hi Cxdinter,

I performed tests for both wc_SignatureGenerate and wc_SignatureVerify against openssl and all passed using WC_SIGNATURE_TYPE_RSA_W_ENC with WC_HASH_TYPE_SHA256.

When using the WC_SIGNATURE_TYPE_RSA_W_ENC  with wc_SignatureVerify it takes in original data being validated, hashes it, adds the DER encoding (which includes the hash OID) and compares the provided signature. This behavior is correct.

These tests were done using the code here:
https://github.com/wolfSSL/wolfssl-examples/pull/27

This was run from inside the wolfssl-examples/signature directory.

Generate a signature and compare hex output (wolfSSL vs. openssl):
./signature README.md 3 5
openssl dgst -sha256 -sign ../certs/client-key.der -keyform der -hex README.md
Result of both RSA Sign with SHA256 hex output = Matches

Sign and verify using openssl. Save sign as sign.txt.
openssl dgst -sha256 -sign ../certs/client-key.der -keyform der -out sign.txt README.md
openssl dgst -sha256 -verify ../certs/client-keyPub.der -keyform der -signature sign.txt README.md
Verified OK

Use sign.txt to verify signature using wolfSSL.
./signature README.md 3 5 sign.txt
RSA Signature Verification: Pass (0)

If you are still having the issue can you provide some examples for your openssl commands and your specific wc_SignatureVerify arguments?

Thanks,
David Garske, wolfSSL

Hi Cxdinter,

Openssl adds a DER encoding on their RSA signature by default. Try using sig_type= "WC_SIGNATURE_TYPE_RSA_W_ENC".

Let me know if that helps.

Thanks,
David Garske, wolfSSL

Hi Andrey,

To enable SHA384 you must also defined "WOLFSSL_SHA512". The code for SHA384 is dependent on SHA512.

To disable SHA256 you will also have to disable the P-RNG is wolfSSL, since it requires SHA256. You are welcome to do this if you have a good hardware RNG source.

Here is an example for disabling the P-RNG:
https://github.com/wolfSSL/wolfssl/blob … ngs.h#L265
https://github.com/wolfSSL/wolfssl/blob … rget.c#L40

Additionally you will need to of course define NO_SHA256:
#define NO_SHA256

In my testing for this I located an issue in our code which assumes SHA256 is present in SendCertificateVerify. A fix for that is located here:
https://github.com/wolfSSL/wolfssl/pull/625

Thanks and please let me know if you have anymore questions.
David Garske, wolfSSL

Hi Jesussotofan,

I did a search for Arduino RNG and came up with this good result:
https://www.arduino.cc/en/Reference/Random

To implement option #2 you need to add the following to your settings.h or user_settins.h (if WOLFSSL_USER_SETTINGS is defined).

int rand_gen_seed(byte* output, word32 sz);
#define CUSTOM_RAND_GENERATE_SEED  rand_gen_seed

Then the function can be put into any .c file in your project (wherever it makes sense to you).

The function would look like:

int rand_gen_seed(byte* output, word32 sz)
{
    int i;
    for (i = 0; i < sz; i++ ) {
        output[i] = analogRead(0);
    }

    return 0;
}

Its important to have a good random seed, so if your micro controller has an RNG peripheral you should find example code for it and use it. The above example uses analog source 0 noise to seed the P-RNG, which is from the reference to website provided above.

Our random.c file has many references to RNG hardware implementations, so check and see if your micro-controller is already listed in there. If so you can define the value needed to enable it.

Let me know if you have any other questions.

Thanks,
David Garske, wolfSSL

Hi Eshober,

We do have a Microchip MLA example with SMTP support. Please send an email to support@wolfssl.com and we can send you a link for it.

Thanks,
David Garske, wolfSSL