int main( int argc, char *argv[] )
{
FILE *f;
int ret;
size_t n, buflen;
int server_fd = -1;
unsigned char *p, *end;
unsigned char buf[2048];
unsigned char hash[20];
const char *pers = "dh_client";
entropy_context entropy;
ctr_drbg_context ctr_drbg;
rsa_context rsa;
dhm_context dhm;
aes_context aes;
((void) argc);
((void) argv);
memset( &rsa, 0, sizeof( rsa ) );
memset( &dhm, 0, sizeof( dhm ) );
/*
* 1. Setup the RNG
*/
printf( "\n . Seeding the random number generator" );
fflush( stdout );
entropy_init( &entropy );
if( ( ret = ctr_drbg_init( &ctr_drbg, entropy_func, &entropy,
(const unsigned char *) pers,
strlen( pers ) ) ) != 0 )
{
printf( " failed\n ! ctr_drbg_init returned %d\n", ret );
goto exit;
}
/*
* 2. Read the server's public RSA key
*/
printf( "\n . Reading public key from rsa_pub.txt" );
fflush( stdout );
if( ( f = fopen( "rsa_pub.txt", "rb" ) ) == NULL )
{
ret = 1;
printf( " failed\n ! Could not open rsa_pub.txt\n" \
" ! Please run rsa_genkey first\n\n" );
goto exit;
}
rsa_init( &rsa, RSA_PKCS_V15, 0 );
if( ( ret = mpi_read_file( &rsa.N, 16, f ) ) != 0 ||
( ret = mpi_read_file( &rsa.E, 16, f ) ) != 0 )
{
printf( " failed\n ! mpi_read_file returned %d\n\n", ret );
goto exit;
}
rsa.len = ( mpi_msb( &rsa.N ) + 7 ) >> 3;
fclose( f );
/*
* 3. Initiate the connection
*/
printf( "\n . Connecting to tcp/%s/%d", SERVER_NAME,
SERVER_PORT );
fflush( stdout );
if( ( ret = net_connect( &server_fd, SERVER_NAME,
SERVER_PORT ) ) != 0 )
{
printf( " failed\n ! net_connect returned %d\n\n", ret );
goto exit;
}
/*
* 4a. First get the buffer length
*/
printf( "\n . Receiving the server's DH parameters" );
fflush( stdout );
memset( buf, 0, sizeof( buf ) );
if( ( ret = net_recv( &server_fd, buf, 2 ) ) != 2 )
{
printf( " failed\n ! net_recv returned %d\n\n", ret );
goto exit;
}
n = buflen = ( buf[0] << 8 ) | buf[1];
if( buflen < 1 || buflen > sizeof( buf ) )
{
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 = net_recv( &server_fd, buf, n ) ) != (int) n )
{
printf( " failed\n ! net_recv returned %d\n\n", ret );
goto exit;
}
p = buf, end = buf + buflen;
if( ( ret = dhm_read_params( &dhm, &p, end ) ) != 0 )
{
printf( " failed\n ! dhm_read_params returned %d\n\n", ret );
goto exit;
}
if( dhm.len < 64 || dhm.len > 512 )
{
ret = 1;
printf( " failed\n ! Invalid DHM modulus size\n\n" );
goto exit;
}
/*
* 5. Check that the server's RSA signature matches
* the SHA-1 hash of (P,G,Ys)
*/
printf( "\n . Verifying the server's RSA signature" );
fflush( stdout );
p += 2;
if( ( n = (size_t) ( end - p ) ) != rsa.len )
{
ret = 1;
printf( " failed\n ! Invalid RSA signature size\n\n" );
goto exit;
}
sha1( buf, (int)( p - 2 - buf ), hash );
if( ( ret = rsa_pkcs1_verify( &rsa, RSA_PUBLIC, SIG_RSA_SHA1,
0, hash, p ) ) != 0 )
{
printf( " failed\n ! rsa_pkcs1_verify returned %d\n\n", ret );
goto exit;
}
/*
* 6. Send our public value: Yc = G ^ Xc mod P
*/
printf( "\n . Sending own public value to server" );
fflush( stdout );
n = dhm.len;
if( ( ret = dhm_make_public( &dhm, dhm.len, buf, n,
ctr_drbg_random, &ctr_drbg ) ) != 0 )
{
printf( " failed\n ! dhm_make_public returned %d\n\n", ret );
goto exit;
}
if( ( ret = net_send( &server_fd, buf, n ) ) != (int) n )
{
printf( " failed\n ! net_send returned %d\n\n", ret );
goto exit;
}
/*
* 7. Derive the shared secret: K = Ys ^ Xc mod P
*/
printf( "\n . Shared secret: " );
fflush( stdout );
n = dhm.len;
if( ( ret = dhm_calc_secret( &dhm, buf, &n ) ) != 0 )
{
printf( " failed\n ! dhm_calc_secret returned %d\n\n", ret );
goto exit;
}
for( n = 0; n < 16; n++ )
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.
*/
printf( "...\n . Receiving and decrypting the ciphertext" );
fflush( stdout );
aes_setkey_dec( &aes, buf, 256 );
memset( buf, 0, sizeof( buf ) );
if( ( ret = net_recv( &server_fd, buf, 16 ) ) != 16 )
{
printf( " failed\n ! net_recv returned %d\n\n", ret );
goto exit;
}
aes_crypt_ecb( &aes, AES_DECRYPT, buf, buf );
buf[16] = '\0';
printf( "\n . Plaintext is \"%s\"\n\n", (char *) buf );
exit:
net_close( server_fd );
rsa_free( &rsa );
dhm_free( &dhm );
#if defined(_WIN32)
printf( " + Press Enter to exit this program.\n" );
fflush( stdout ); getchar();
#endif
return( ret );
}
int main( int argc, char *argv[] )
{
FILE *f;
int ret, i, c;
rsa_context rsa;
unsigned char hash[20];
unsigned char buf[512];
ret = 1;
if( argc != 2 )
{
printf( "usage: rsa_verify <filename>\n" );
#ifdef WIN32
printf( "\n" );
#endif
goto exit;
}
printf( "\n . Reading public key from rsa_pub.txt" );
fflush( stdout );
if( ( f = fopen( "rsa_pub.txt", "rb" ) ) == NULL )
{
printf( " failed\n ! Could not open rsa_pub.txt\n" \
" ! Please run rsa_genkey first\n\n" );
goto exit;
}
rsa_init( &rsa, RSA_PKCS_V15, 0, NULL, NULL );
if( ( ret = mpi_read_file( &rsa.N, 16, f ) ) != 0 ||
( ret = mpi_read_file( &rsa.E, 16, f ) ) != 0 )
{
printf( " failed\n ! mpi_read_file returned %d\n\n", ret );
goto exit;
}
rsa.len = ( mpi_msb( &rsa.N ) + 7 ) >> 3;
fclose( f );
/*
* Extract the RSA signature from the text file
*/
ret = 1;
i = strlen( argv[1] );
memcpy( argv[1] + i, ".sig", 5 );
if( ( f = fopen( argv[1], "rb" ) ) == NULL )
{
printf( "\n ! Could not open %s\n\n", argv[1] );
goto exit;
}
argv[1][i] = '\0', i = 0;
while( fscanf( f, "%02X", &c ) > 0 &&
i < (int) sizeof( buf ) )
buf[i++] = (unsigned char) c;
fclose( f );
if( i != rsa.len )
{
printf( "\n ! Invalid RSA signature format\n\n" );
goto exit;
}
/*
* Compute the SHA-1 hash of the input file and compare
* it with the hash decrypted from the RSA signature.
*/
printf( "\n . Verifying the RSA/SHA-1 signature" );
fflush( stdout );
if( ( ret = sha1_file( argv[1], hash ) ) != 0 )
{
printf( " failed\n ! Could not open or read %s\n\n", argv[1] );
goto exit;
}
if( ( ret = rsa_pkcs1_verify( &rsa, RSA_PUBLIC, RSA_SHA1,
20, hash, buf ) ) != 0 )
{
printf( " failed\n ! rsa_pkcs1_verify returned %d\n\n", ret );
goto exit;
}
printf( "\n . OK (the decrypted SHA-1 hash matches)\n\n" );
ret = 0;
exit:
#ifdef WIN32
printf( " + Press Enter to exit this program.\n" );
fflush( stdout ); getchar();
#endif
return( ret );
}
int main( int argc, char *argv[] )
{
FILE *f;
int ret, i;
rsa_context rsa;
unsigned char hash[20];
unsigned char buf[512];
ret = 1;
if( argc != 2 )
{
printf( "usage: rsa_sign <filename>\n" );
#ifdef WIN32
printf( "\n" );
#endif
goto exit;
}
printf( "\n . Reading private key from rsa_priv.txt" );
fflush( stdout );
if( ( f = fopen( "rsa_priv.txt", "rb" ) ) == NULL )
{
ret = 1;
printf( " failed\n ! Could not open rsa_priv.txt\n" \
" ! Please run rsa_genkey first\n\n" );
goto exit;
}
rsa_init( &rsa, RSA_PKCS_V15, 0, NULL, NULL );
if( ( ret = mpi_read_file( &rsa.N , 16, f ) ) != 0 ||
( ret = mpi_read_file( &rsa.E , 16, f ) ) != 0 ||
( ret = mpi_read_file( &rsa.D , 16, f ) ) != 0 ||
( ret = mpi_read_file( &rsa.P , 16, f ) ) != 0 ||
( ret = mpi_read_file( &rsa.Q , 16, f ) ) != 0 ||
( ret = mpi_read_file( &rsa.DP, 16, f ) ) != 0 ||
( ret = mpi_read_file( &rsa.DQ, 16, f ) ) != 0 ||
( ret = mpi_read_file( &rsa.QP, 16, f ) ) != 0 )
{
printf( " failed\n ! mpi_read_file returned %d\n\n", ret );
goto exit;
}
rsa.len = ( mpi_msb( &rsa.N ) + 7 ) >> 3;
fclose( f );
/*
* Compute the SHA-1 hash of the input file,
* then calculate the RSA signature of the hash.
*/
printf( "\n . Generating the RSA/SHA-1 signature" );
fflush( stdout );
if( ( ret = sha1_file( argv[1], hash ) ) != 0 )
{
printf( " failed\n ! Could not open or read %s\n\n", argv[1] );
goto exit;
}
if( ( ret = rsa_pkcs1_sign( &rsa, RSA_PRIVATE, SIG_RSA_SHA1,
20, hash, buf ) ) != 0 )
{
printf( " failed\n ! rsa_pkcs1_sign returned %d\n\n", ret );
goto exit;
}
/*
* Write the signature into <filename>-sig.txt
*/
memcpy( argv[1] + strlen( argv[1] ), ".sig", 5 );
if( ( f = fopen( argv[1], "wb+" ) ) == NULL )
{
ret = 1;
printf( " failed\n ! Could not create %s\n\n", argv[1] );
goto exit;
}
for( i = 0; i < rsa.len; i++ )
fprintf( f, "%02X%s", buf[i],
( i + 1 ) % 16 == 0 ? "\r\n" : " " );
fclose( f );
printf( "\n . Done (created \"%s\")\n\n", argv[1] );
exit:
#ifdef WIN32
printf( " + Press Enter to exit this program.\n" );
fflush( stdout ); getchar();
#endif
return( ret );
}
int decipher_buffer(unsigned char **output, int *output_len,
unsigned char *input, int input_len,
char *priv_key_file)
{
int offset, ret;
size_t key_len;
unsigned char s_key[32] = {0};
aes_context aes_ctx;
rsa_context rsa_ctx;
FILE *f;
unsigned char iv[16] = {
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
};
/* *** Init *** */
ret = 1;
offset = 0;
key_len = 0;
f = NULL;
/* *** Get private key *** */
f = fopen(priv_key_file, "rb");
if (f == NULL) {
fprintf(stderr, "error : unable to open %s\n", priv_key_file);
ret = 1;
goto cleanup;
}
rsa_init(&rsa_ctx, RSA_PKCS_V15, 0 );
if (mpi_read_file(&rsa_ctx.N, 16, f) != 0
|| mpi_read_file(&rsa_ctx.E, 16, f) != 0
|| mpi_read_file(&rsa_ctx.D, 16, f) != 0
|| mpi_read_file(&rsa_ctx.P, 16, f) != 0
|| mpi_read_file(&rsa_ctx.Q, 16, f) != 0
|| mpi_read_file(&rsa_ctx.DP, 16, f) != 0
|| mpi_read_file(&rsa_ctx.DQ, 16, f) != 0
|| mpi_read_file(&rsa_ctx.QP, 16, f) != 0) {
fprintf(stderr, "error : unable to read private key\n");
ret = 1;
goto cleanup;
}
rsa_ctx.len = (mpi_msb(&rsa_ctx.N ) + 7 ) >> 3;
/* *** Decipher *** */
ret = rsa_pkcs1_decrypt(&rsa_ctx, RSA_PRIVATE, &key_len,
input, s_key, 16);
if (ret != 0) {
fprintf(stderr, "error : rsa_pkcs1_decrypt failed\n");
ret = 1;
goto cleanup;
}
ret = aes_setkey_dec(&aes_ctx, s_key, 256);
if (ret != 0) {
fprintf(stderr, "error : aes_setkey_dec failed\n");
ret = 1;
goto cleanup;
}
/* *** Plain text *** */
*output = (unsigned char *) malloc((input_len - 128) *
sizeof(unsigned char));
memset(*output, 0, input_len - 128);
ret = aes_crypt_cbc(&aes_ctx, AES_DECRYPT, input_len - 128 , iv,
input + 128, *output);
if (ret != 0) {
fprintf(stderr, "error : aes_crypt_cbc failed\n");
ret = 1;
goto cleanup;
}
/* *** Padding *** */
for (offset = input_len - 128 - 1; offset >= 0; offset--) {
if((*output)[offset] == 0x80) {
*output_len = offset;
(*output)[offset] = 0x00;
break;
}
}
cleanup:
if(f != NULL)
fclose(f);
rsa_free(&rsa_ctx);
return ret;
}
int sign(unsigned char *output,unsigned char *input, int input_len, char *pri_key_file)
{
unsigned char * cipher = NULL;
unsigned char * k_c = NULL;
unsigned char sign[128];
int ret;
FILE *fkey;
rsa_context rsa_ctx;
havege_state prng_ctx;
cipher = (unsigned char *)malloc((32)*sizeof(char));
/* ********************** HASH controle integrite *********************** */
k_c = (unsigned char *)malloc(2*KEY_LENGTH*sizeof(unsigned char));
memset(k_c, 0, 2*KEY_LENGTH);
//generation de la clef symetrique de KEY_LENGTH bits
gen_key(k_c, KEY_LENGTH);
sha2_hmac(k_c, KEY_LENGTH, input, input_len, cipher, 0);
print_hex(k_c, KEY_LENGTH, "cle secrete utilisée pour le hash : ");
/* *** Read the private asymetric key in the file*** */
if( ( fkey = fopen( pri_key_file, "rb" ) ) == NULL ) {
ret = 1;
printf( " failed\n ! Could not open %s\n" \
" ! Please run rsa_genkey first\n\n",pri_key_file );
goto cleanup;
}
rsa_init( &rsa_ctx, RSA_PKCS_V15, 0 );
if( ( ret = mpi_read_file( &rsa_ctx.N , 16, fkey ) ) != 0 ||
( ret = mpi_read_file( &rsa_ctx.E , 16, fkey ) ) != 0 ||
( ret = mpi_read_file( &rsa_ctx.D , 16, fkey ) ) != 0 ||
( ret = mpi_read_file( &rsa_ctx.P , 16, fkey ) ) != 0 ||
( ret = mpi_read_file( &rsa_ctx.Q , 16, fkey ) ) != 0 ||
( ret = mpi_read_file( &rsa_ctx.DP, 16, fkey ) ) != 0 ||
( ret = mpi_read_file( &rsa_ctx.DQ, 16, fkey ) ) != 0 ||
( ret = mpi_read_file( &rsa_ctx.QP, 16, fkey ) ) != 0 )
{
printf( " failed\n ! mpi_read_file returned %d\n\n", ret );
goto cleanup;
}
rsa_ctx.len = ( mpi_msb( &rsa_ctx.N ) + 7 ) >> 3;
fclose( fkey );
/* *** SYM_K(key) : chiffrement RSA de la clé de chiffrement key (16) => rsa-1024 bits = 128 octets en sortie *** */
/* *** cipher = ASYM_Kpriv (Hash) *** */
havege_init(&prng_ctx);
memset(sign, 0, 128);
if( ( ret = rsa_pkcs1_encrypt( &rsa_ctx, havege_random, &prng_ctx, RSA_PRIVATE, KEY_LENGTH, cipher, sign ) ) != 0 ) {
printf( " failed\n ! rsa_pkcs1_encrypt returned %d\n\n", ret );
goto cleanup;
}
print_hex(sign, sizeof(sign), "Hash chiffrée avec RSA : ");
/* *** ASYM_Kpub (K) *** */
output = (unsigned char *) malloc( 128 * sizeof(unsigned char));
memcpy(output, sign, 128);
cleanup:
if(cipher != NULL) {
memset(cipher, 0, 32);
free(cipher);
}
if(k_c != NULL) {
memset(k_c, 0, 2*KEY_LENGTH);
free(k_c);
}
memset(&prng_ctx,0x00, sizeof(havege_state));
memset(&rsa_ctx, 0x00, sizeof(rsa_ctx));
memset(sign, 0, 128);
return ret;
}
int main( int argc, char *argv[] )
{
FILE *f;
int ret, c;
size_t i;
rsa_context rsa;
entropy_context entropy;
ctr_drbg_context ctr_drbg;
unsigned char result[1024];
unsigned char buf[512];
const char *pers = "rsa_decrypt";
((void) argv);
memset(result, 0, sizeof( result ) );
ret = 1;
if( argc != 1 )
{
polarssl_printf( "usage: rsa_decrypt\n" );
#if defined(_WIN32)
polarssl_printf( "\n" );
#endif
goto exit;
}
polarssl_printf( "\n . Seeding the random number generator..." );
fflush( stdout );
entropy_init( &entropy );
if( ( ret = ctr_drbg_init( &ctr_drbg, entropy_func, &entropy,
(const unsigned char *) pers,
strlen( pers ) ) ) != 0 )
{
polarssl_printf( " failed\n ! ctr_drbg_init returned %d\n", ret );
goto exit;
}
polarssl_printf( "\n . Reading private key from rsa_priv.txt" );
fflush( stdout );
if( ( f = fopen( "rsa_priv.txt", "rb" ) ) == NULL )
{
polarssl_printf( " failed\n ! Could not open rsa_priv.txt\n" \
" ! Please run rsa_genkey first\n\n" );
goto exit;
}
rsa_init( &rsa, RSA_PKCS_V15, 0 );
if( ( ret = mpi_read_file( &rsa.N , 16, f ) ) != 0 ||
( ret = mpi_read_file( &rsa.E , 16, f ) ) != 0 ||
( ret = mpi_read_file( &rsa.D , 16, f ) ) != 0 ||
( ret = mpi_read_file( &rsa.P , 16, f ) ) != 0 ||
( ret = mpi_read_file( &rsa.Q , 16, f ) ) != 0 ||
( ret = mpi_read_file( &rsa.DP, 16, f ) ) != 0 ||
( ret = mpi_read_file( &rsa.DQ, 16, f ) ) != 0 ||
( ret = mpi_read_file( &rsa.QP, 16, f ) ) != 0 )
{
polarssl_printf( " failed\n ! mpi_read_file returned %d\n\n", ret );
goto exit;
}
rsa.len = ( mpi_msb( &rsa.N ) + 7 ) >> 3;
fclose( f );
/*
* Extract the RSA encrypted value from the text file
*/
ret = 1;
if( ( f = fopen( "result-enc.txt", "rb" ) ) == NULL )
{
polarssl_printf( "\n ! Could not open %s\n\n", "result-enc.txt" );
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 )
{
polarssl_printf( "\n ! Invalid RSA signature format\n\n" );
goto exit;
}
/*
* Decrypt the encrypted RSA data and print the result.
*/
polarssl_printf( "\n . Decrypting the encrypted data" );
fflush( stdout );
if( ( ret = rsa_pkcs1_decrypt( &rsa, ctr_drbg_random, &ctr_drbg,
RSA_PRIVATE, &i, buf, result,
1024 ) ) != 0 )
{
polarssl_printf( " failed\n ! rsa_pkcs1_decrypt returned %d\n\n", ret );
goto exit;
}
polarssl_printf( "\n . OK\n\n" );
polarssl_printf( "The decrypted result is: '%s'\n\n", result );
ret = 0;
exit:
ctr_drbg_free( &ctr_drbg );
entropy_free( &entropy );
#if defined(_WIN32)
polarssl_printf( " + Press Enter to exit this program.\n" );
fflush( stdout ); getchar();
#endif
return( ret );
}
