Zeroize temporary buffers used to sanity-check the signature.
If there is an error, overwrite the tentative signature in the output
buffer.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Declare mbedtls_md functions as MBEDTLS_CHECK_RETURN_TYPICAL, meaning that
their return values should be checked.
Do check the return values in our code. We were already doing that
everywhere for hash calculations, but not for HMAC calculations.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Zeroize local MAC variables used for CBC+HMAC cipher suites. In encryption,
this is just good hygiene but probably not needed for security since the
data protected by the MAC that could leak is about to be transmitted anyway.
In DTLS decryption, this could be a security issue since an adversary could
learn the MAC of data that they were trying to inject. At least with
encrypt-then-MAC, the adversary could then easily inject a datagram with
a corrected packet. TLS would still be safe since the receiver would close
the connection after the bad MAC.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Expected output generated by OpenSSL (see below) apart from the case
where both password and salt are either NULL or zero length, as OpenSSL
does not support this. For these test cases we have had to use our own
output as that which is expected. Code to generate test cases is as
follows:
#include <openssl/pkcs12.h>
#include <openssl/evp.h>
#include <string.h>
int Keygen_Uni( const char * test_name, unsigned char *pass, int
passlen, unsigned char *salt,
int saltlen, int id, int iter, int n,
unsigned char *out, const EVP_MD
*md_type )
{
size_t index;
printf( "%s\n", test_name );
int ret = PKCS12_key_gen_uni( pass, passlen, salt, saltlen, id, iter,
n, out, md_type );
if( ret != 1 )
{
printf( "Key generation returned %d\n", ret );
}
else
{
for( index = 0; index < n; ++index )
{
printf( "%02x", out[index] );
}
printf( "\n" );
}
printf( "\n" );
}
int main(void)
{
unsigned char out_buf[48];
unsigned char pass[64];
int pass_len;
unsigned char salt[64];
int salt_len;
/* If ID=1, then the pseudorandom bits being produced are to be used
as key material for performing encryption or decryption.
If ID=2, then the pseudorandom bits being produced are to be
used as an IV (Initial Value) for encryption or decryption.
If ID=3, then the pseudorandom bits being produced are
to be used as an integrity key for MACing.
*/
int id = 1;
int iter = 3;
memset( out_buf, 0, sizeof( out_buf ) );
memset( pass, 0, sizeof( pass ) );
memset( salt, 0, sizeof( salt ) );
Keygen_Uni( "Zero length pass and salt", pass, 0, salt, 0, id, iter,
sizeof(out_buf),
out_buf, EVP_md5( ) );
memset( out_buf, 0, sizeof( out_buf ) );
Keygen_Uni( "NULL pass and salt", NULL, 0, NULL, 0, id, iter,
sizeof(out_buf),
out_buf, EVP_md5( ) );
memset( out_buf, 0, sizeof( out_buf ) );
salt[0] = 0x01;
salt[1] = 0x23;
salt[2] = 0x45;
salt[3] = 0x67;
salt[4] = 0x89;
salt[5] = 0xab;
salt[6] = 0xcd;
salt[7] = 0xef;
Keygen_Uni( "Zero length pass", pass, 0, salt, 8, id, iter,
sizeof(out_buf),
out_buf, EVP_md5( ) );
memset( out_buf, 0, sizeof( out_buf ) );
Keygen_Uni( "NULL pass", NULL, 0, salt, 8, id, iter, sizeof(out_buf),
out_buf, EVP_md5( ) );
memset( out_buf, 0, sizeof( out_buf ) );
memset( salt, 0, sizeof( salt ) );
pass[0] = 0x01;
pass[1] = 0x23;
pass[2] = 0x45;
pass[3] = 0x67;
pass[4] = 0x89;
pass[5] = 0xab;
pass[6] = 0xcd;
pass[7] = 0xef;
Keygen_Uni( "Zero length salt", pass, 8, salt, 0, id, iter,
sizeof(out_buf),
out_buf, EVP_md5( ) );
memset( out_buf, 0, sizeof( out_buf ) );
Keygen_Uni( "NULL salt", pass, 8, NULL, 0, id, iter, sizeof(out_buf),
out_buf, EVP_md5( ) );
memset( out_buf, 0, sizeof( out_buf ) );
salt[0] = 0x01;
salt[1] = 0x23;
salt[2] = 0x45;
salt[3] = 0x67;
salt[4] = 0x89;
salt[5] = 0xab;
salt[6] = 0xcd;
salt[7] = 0xef;
Keygen_Uni( "Valid pass and salt", pass, 8, salt, 8, id, iter,
sizeof(out_buf),
out_buf, EVP_md5( ) );
return 0;
}
Signed-off-by: Paul Elliott <paul.elliott@arm.com>
Can't call mbedtls_cipher_free(&invalid_ctx) in cleanup if
mbedtls_cipher_init(&invalid_ctx) hasn't been called.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
As we have now a minimal viable implementation of TLS 1.3,
let's remove EXPERIMENTAL from the config option enabling
it.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
