static int rsa_verify_wrap( void *ctx, mbedtls_md_type_t md_alg,
const unsigned char *hash, size_t hash_len,
const unsigned char *sig, size_t sig_len )
{
int ret;
mbedtls_rsa_context * rsa = (mbedtls_rsa_context *) ctx;
size_t rsa_len = mbedtls_rsa_get_len( rsa );
#if SIZE_MAX > UINT_MAX
if( md_alg == MBEDTLS_MD_NONE && UINT_MAX < hash_len )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
#endif /* SIZE_MAX > UINT_MAX */
if( sig_len < rsa_len )
return( MBEDTLS_ERR_RSA_VERIFY_FAILED );
if( ( ret = mbedtls_rsa_pkcs1_verify( rsa, NULL, NULL,
MBEDTLS_RSA_PUBLIC, md_alg,
(unsigned int) hash_len, hash, sig ) ) != 0 )
return( ret );
/* The buffer contains a valid signature followed by extra data.
* We have a special error code for that so that so that callers can
* use mbedtls_pk_verify() to check "Does the buffer start with a
* valid signature?" and not just "Does the buffer contain a valid
* signature?". */
if( sig_len > rsa_len )
return( MBEDTLS_ERR_PK_SIG_LEN_MISMATCH );
return( 0 );
}
const bool FrostIdentity::VerifySignature(const std::vector<unsigned char> &data, const std::string &signature)
{
if(data.size()>0 && signature!="")
{
std::vector<unsigned char> sigdata;
std::vector<unsigned char> hashdata(20,0);
unsigned long hashlen=hashdata.size();
int rval;
rval=0;
if(Base64::Decode(signature,sigdata)==true)
{
mbedtls_sha1(&data[0],data.size(),&hashdata[0]);
m_rsa.len=sigdata.size();
mbedtls_rsa_pkcs1_verify(&m_rsa,0,0,MBEDTLS_RSA_PUBLIC,MBEDTLS_MD_SHA1,hashdata.size(),&hashdata[0],&sigdata[0]);
return (rval==0) ? true : false;
}
else
{
return false;
}
}
else
{
return false;
}
}
int verify_signature(const unsigned char *signature,
const unsigned char *pubkey,
const unsigned char *expected_hmac)
{
rsa_context rsa;
init_rsa_context_with_public_key(&rsa, pubkey);
#ifdef USE_MBEDTLS
int ret = mbedtls_rsa_pkcs1_verify(&rsa, mbedtls_default_rng, nullptr, MBEDTLS_RSA_PUBLIC, MBEDTLS_MD_NONE, 20,
expected_hmac, signature);
#else
int ret = rsa_pkcs1_verify(&rsa, (rsa_mode_t)RSA_PUBLIC, (rsa_hash_id_t)RSA_RAW, 20,
expected_hmac, signature);
#endif
rsa_free(&rsa);
return ret;
}
static int rsa_verify_wrap( void *ctx, mbedtls_md_type_t md_alg,
const unsigned char *hash, size_t hash_len,
const unsigned char *sig, size_t sig_len )
{
int ret;
if( sig_len < ((mbedtls_rsa_context *) ctx)->len )
return( MBEDTLS_ERR_RSA_VERIFY_FAILED );
if( ( ret = mbedtls_rsa_pkcs1_verify( (mbedtls_rsa_context *) ctx, NULL, NULL,
MBEDTLS_RSA_PUBLIC, md_alg,
(unsigned int) hash_len, hash, sig ) ) != 0 )
return( ret );
if( sig_len > ((mbedtls_rsa_context *) ctx)->len )
return( MBEDTLS_ERR_PK_SIG_LEN_MISMATCH );
return( 0 );
}
int main( void )
{
FILE *f;
int ret;
size_t n, buflen;
mbedtls_net_context server_fd;
unsigned char *p, *end;
unsigned char buf[2048];
unsigned char hash[32];
const char *pers = "dh_client";
mbedtls_entropy_context entropy;
mbedtls_ctr_drbg_context ctr_drbg;
mbedtls_rsa_context rsa;
mbedtls_dhm_context dhm;
mbedtls_aes_context aes;
mbedtls_net_init( &server_fd );
mbedtls_rsa_init( &rsa, MBEDTLS_RSA_PKCS_V15, MBEDTLS_MD_SHA256 );
mbedtls_dhm_init( &dhm );
mbedtls_aes_init( &aes );
mbedtls_ctr_drbg_init( &ctr_drbg );
/*
* 1. Setup the RNG
*/
mbedtls_printf( "\n . Seeding the random number generator" );
fflush( stdout );
mbedtls_entropy_init( &entropy );
if( ( ret = mbedtls_ctr_drbg_seed( &ctr_drbg, mbedtls_entropy_func, &entropy,
(const unsigned char *) pers,
strlen( pers ) ) ) != 0 )
{
mbedtls_printf( " failed\n ! mbedtls_ctr_drbg_seed returned %d\n", ret );
goto exit;
}
/*
* 2. Read the server's public RSA key
*/
mbedtls_printf( "\n . Reading public key from rsa_pub.txt" );
fflush( stdout );
if( ( f = fopen( "rsa_pub.txt", "rb" ) ) == NULL )
{
ret = 1;
mbedtls_printf( " failed\n ! Could not open rsa_pub.txt\n" \
" ! Please run rsa_genkey first\n\n" );
goto exit;
}
mbedtls_rsa_init( &rsa, MBEDTLS_RSA_PKCS_V15, 0 );
if( ( ret = mbedtls_mpi_read_file( &rsa.N, 16, f ) ) != 0 ||
( ret = mbedtls_mpi_read_file( &rsa.E, 16, f ) ) != 0 )
{
mbedtls_printf( " failed\n ! mbedtls_mpi_read_file returned %d\n\n", ret );
goto exit;
}
rsa.len = ( mbedtls_mpi_bitlen( &rsa.N ) + 7 ) >> 3;
fclose( f );
/*
* 3. Initiate the connection
*/
mbedtls_printf( "\n . Connecting to tcp/%s/%s", SERVER_NAME,
SERVER_PORT );
fflush( stdout );
if( ( ret = mbedtls_net_connect( &server_fd, SERVER_NAME,
SERVER_PORT, MBEDTLS_NET_PROTO_TCP ) ) != 0 )
{
mbedtls_printf( " failed\n ! mbedtls_net_connect returned %d\n\n", ret );
goto exit;
}
/*
* 4a. First get the buffer length
*/
mbedtls_printf( "\n . Receiving the server's DH parameters" );
fflush( stdout );
memset( buf, 0, sizeof( buf ) );
if( ( ret = mbedtls_net_recv( &server_fd, buf, 2 ) ) != 2 )
{
mbedtls_printf( " failed\n ! mbedtls_net_recv returned %d\n\n", ret );
goto exit;
}
n = buflen = ( buf[0] << 8 ) | buf[1];
if( buflen < 1 || buflen > sizeof( buf ) )
{
mbedtls_printf( " failed\n ! Got an invalid buffer length\n\n" );
goto exit;
}
/*
* 4b. Get the DHM parameters: P, G and Ys = G^Xs mod P
*/
memset( buf, 0, sizeof( buf ) );
if( ( ret = mbedtls_net_recv( &server_fd, buf, n ) ) != (int) n )
{
mbedtls_printf( " failed\n ! mbedtls_net_recv returned %d\n\n", ret );
goto exit;
}
p = buf, end = buf + buflen;
if( ( ret = mbedtls_dhm_read_params( &dhm, &p, end ) ) != 0 )
{
mbedtls_printf( " failed\n ! mbedtls_dhm_read_params returned %d\n\n", ret );
goto exit;
}
if( dhm.len < 64 || dhm.len > 512 )
{
ret = 1;
mbedtls_printf( " failed\n ! Invalid DHM modulus size\n\n" );
goto exit;
}
/*
* 5. Check that the server's RSA signature matches
* the SHA-256 hash of (P,G,Ys)
*/
mbedtls_printf( "\n . Verifying the server's RSA signature" );
fflush( stdout );
p += 2;
if( ( n = (size_t) ( end - p ) ) != rsa.len )
{
ret = 1;
mbedtls_printf( " failed\n ! Invalid RSA signature size\n\n" );
goto exit;
}
mbedtls_sha1( buf, (int)( p - 2 - buf ), hash );
if( ( ret = mbedtls_rsa_pkcs1_verify( &rsa, NULL, NULL, MBEDTLS_RSA_PUBLIC,
MBEDTLS_MD_SHA256, 0, hash, p ) ) != 0 )
{
mbedtls_printf( " failed\n ! mbedtls_rsa_pkcs1_verify returned %d\n\n", ret );
goto exit;
}
/*
* 6. Send our public value: Yc = G ^ Xc mod P
*/
mbedtls_printf( "\n . Sending own public value to server" );
fflush( stdout );
n = dhm.len;
if( ( ret = mbedtls_dhm_make_public( &dhm, (int) dhm.len, buf, n,
mbedtls_ctr_drbg_random, &ctr_drbg ) ) != 0 )
{
mbedtls_printf( " failed\n ! mbedtls_dhm_make_public returned %d\n\n", ret );
goto exit;
}
if( ( ret = mbedtls_net_send( &server_fd, buf, n ) ) != (int) n )
{
mbedtls_printf( " failed\n ! mbedtls_net_send returned %d\n\n", ret );
goto exit;
}
/*
* 7. Derive the shared secret: K = Ys ^ Xc mod P
*/
mbedtls_printf( "\n . Shared secret: " );
fflush( stdout );
if( ( ret = mbedtls_dhm_calc_secret( &dhm, buf, sizeof( buf ), &n,
mbedtls_ctr_drbg_random, &ctr_drbg ) ) != 0 )
{
mbedtls_printf( " failed\n ! mbedtls_dhm_calc_secret returned %d\n\n", ret );
goto exit;
}
for( n = 0; n < 16; n++ )
mbedtls_printf( "%02x", buf[n] );
/*
* 8. Setup the AES-256 decryption key
*
* This is an overly simplified example; best practice is
* to hash the shared secret with a random value to derive
* the keying material for the encryption/decryption keys,
* IVs and MACs.
*/
mbedtls_printf( "...\n . Receiving and decrypting the ciphertext" );
fflush( stdout );
mbedtls_aes_setkey_dec( &aes, buf, 256 );
memset( buf, 0, sizeof( buf ) );
if( ( ret = mbedtls_net_recv( &server_fd, buf, 16 ) ) != 16 )
{
mbedtls_printf( " failed\n ! mbedtls_net_recv returned %d\n\n", ret );
goto exit;
}
mbedtls_aes_crypt_ecb( &aes, MBEDTLS_AES_DECRYPT, buf, buf );
buf[16] = '\0';
mbedtls_printf( "\n . Plaintext is \"%s\"\n\n", (char *) buf );
exit:
mbedtls_net_free( &server_fd );
mbedtls_aes_free( &aes );
mbedtls_rsa_free( &rsa );
mbedtls_dhm_free( &dhm );
mbedtls_ctr_drbg_free( &ctr_drbg );
mbedtls_entropy_free( &entropy );
#if defined(_WIN32)
mbedtls_printf( " + Press Enter to exit this program.\n" );
fflush( stdout ); getchar();
#endif
return( ret );
}
int main( int argc, char *argv[] )
{
FILE *f;
int ret, c;
size_t i;
mbedtls_rsa_context rsa;
unsigned char hash[32];
unsigned char buf[MBEDTLS_MPI_MAX_SIZE];
char filename[512];
ret = 1;
if( argc != 2 )
{
mbedtls_printf( "usage: rsa_verify <filename>\n" );
#if defined(_WIN32)
mbedtls_printf( "\n" );
#endif
goto exit;
}
mbedtls_printf( "\n . Reading public key from rsa_pub.txt" );
fflush( stdout );
if( ( f = fopen( "rsa_pub.txt", "rb" ) ) == NULL )
{
mbedtls_printf( " failed\n ! Could not open rsa_pub.txt\n" \
" ! Please run rsa_genkey first\n\n" );
goto exit;
}
mbedtls_rsa_init( &rsa, MBEDTLS_RSA_PKCS_V15, 0 );
if( ( ret = mbedtls_mpi_read_file( &rsa.N, 16, f ) ) != 0 ||
( ret = mbedtls_mpi_read_file( &rsa.E, 16, f ) ) != 0 )
{
mbedtls_printf( " failed\n ! mbedtls_mpi_read_file returned %d\n\n", ret );
goto exit;
}
rsa.len = ( mbedtls_mpi_bitlen( &rsa.N ) + 7 ) >> 3;
fclose( f );
/*
* Extract the RSA signature from the text file
*/
ret = 1;
mbedtls_snprintf( filename, sizeof(filename), "%s.sig", argv[1] );
if( ( f = fopen( filename, "rb" ) ) == NULL )
{
mbedtls_printf( "\n ! Could not open %s\n\n", filename );
goto exit;
}
i = 0;
while( fscanf( f, "%02X", &c ) > 0 &&
i < (int) sizeof( buf ) )
buf[i++] = (unsigned char) c;
fclose( f );
if( i != rsa.len )
{
mbedtls_printf( "\n ! Invalid RSA signature format\n\n" );
goto exit;
}
/*
* Compute the SHA-256 hash of the input file and
* verify the signature
*/
mbedtls_printf( "\n . Verifying the RSA/SHA-256 signature" );
fflush( stdout );
if( ( ret = mbedtls_md_file(
mbedtls_md_info_from_type( MBEDTLS_MD_SHA256 ),
argv[1], hash ) ) != 0 )
{
mbedtls_printf( " failed\n ! Could not open or read %s\n\n", argv[1] );
goto exit;
}
if( ( ret = mbedtls_rsa_pkcs1_verify( &rsa, NULL, NULL, MBEDTLS_RSA_PUBLIC,
MBEDTLS_MD_SHA256, 20, hash, buf ) ) != 0 )
{
mbedtls_printf( " failed\n ! mbedtls_rsa_pkcs1_verify returned -0x%0x\n\n", -ret );
goto exit;
}
mbedtls_printf( "\n . OK (the signature is valid)\n\n" );
ret = 0;
exit:
#if defined(_WIN32)
mbedtls_printf( " + Press Enter to exit this program.\n" );
fflush( stdout ); getchar();
#endif
return( ret );
}
