- return -1;
- }
- }
-
- if(read_rsa_public_key(c)) {
- return -1;
- }
-
- /* Check some options */
-
- if((get_config_bool(lookup_config(c->config_tree, "IndirectData"), &bla) && bla) || myself->options & OPTION_INDIRECT)
- c->options |= OPTION_INDIRECT;
-
- if((get_config_bool(lookup_config(c->config_tree, "TCPOnly"), &bla) && bla) || myself->options & OPTION_TCPONLY)
- c->options |= OPTION_TCPONLY | OPTION_INDIRECT;
-
- c->allow_request = METAKEY;
-
- return send_metakey(c);
-}
-
-int send_metakey(connection_t *c)
-{
- char buffer[MAX_STRING_SIZE];
- int len, x;
-
- cp();
-
- len = RSA_size(c->rsa_key);
-
- /* Allocate buffers for the meta key */
-
- if(!c->outkey)
- c->outkey = xmalloc(len);
-
- if(!c->outctx)
- c->outctx = xmalloc_and_zero(sizeof(*c->outctx));
- cp();
- /* Copy random data to the buffer */
-
- RAND_bytes(c->outkey, len);
-
- /* The message we send must be smaller than the modulus of the RSA key.
- By definition, for a key of k bits, the following formula holds:
-
- 2^(k-1) <= modulus < 2^(k)
-
- Where ^ means "to the power of", not "xor".
- This means that to be sure, we must choose our message < 2^(k-1).
- This can be done by setting the most significant bit to zero.
- */
-
- c->outkey[0] &= 0x7F;
-
- if(debug_level >= DEBUG_SCARY_THINGS) {
- bin2hex(c->outkey, buffer, len);
- buffer[len * 2] = '\0';
- logger(DEBUG_ALWAYS, LOG_DEBUG, _("Generated random meta key (unencrypted): %s"),
- buffer);
- }
-
- /* Encrypt the random data
-
- We do not use one of the PKCS padding schemes here.
- This is allowed, because we encrypt a totally random string
- with a length equal to that of the modulus of the RSA key.
- */
-
- if(RSA_public_encrypt(len, c->outkey, buffer, c->rsa_key, RSA_NO_PADDING) != len) {
- logger(DEBUG_ALWAYS, LOG_ERR, _("Error during encryption of meta key for %s (%s)"),
- c->name, c->hostname);
- return -1;
- }
-
- /* Convert the encrypted random data to a hexadecimal formatted string */
-
- bin2hex(buffer, buffer, len);
- buffer[len * 2] = '\0';
-
- /* Send the meta key */
-
- x = send_request(c, "%d %d %d %d %d %s", METAKEY,
- c->outcipher ? c->outcipher->nid : 0,
- c->outdigest ? c->outdigest->type : 0, c->outmaclength,
- c->outcompression, buffer);
-
- /* Further outgoing requests are encrypted with the key we just generated */
-
- if(c->outcipher) {
- EVP_EncryptInit(c->outctx, c->outcipher,
- c->outkey + len - c->outcipher->key_len,
- c->outkey + len - c->outcipher->key_len -
- c->outcipher->iv_len);
-
- c->status.encryptout = 1;
- }
-
- return x;
-}
-
-int metakey_h(connection_t *c)
-{
- char buffer[MAX_STRING_SIZE];
- int cipher, digest, maclength, compression;
- int len;
-
- cp();
-
- if(sscanf(c->buffer, "%*d %d %d %d %d " MAX_STRING, &cipher, &digest, &maclength, &compression, buffer) != 5) {
- logger(DEBUG_ALWAYS, LOG_ERR, _("Got bad %s from %s (%s)"), "METAKEY", c->name,
- c->hostname);
- return -1;
- }
-
- len = RSA_size(myself->connection->rsa_key);
-
- /* Check if the length of the meta key is all right */
-
- if(strlen(buffer) != len * 2) {
- logger(DEBUG_ALWAYS, LOG_ERR, _("Possible intruder %s (%s): %s"), c->name, c->hostname, "wrong keylength");
- return -1;
- }
-
- /* Allocate buffers for the meta key */
-
- if(!c->inkey)
- c->inkey = xmalloc(len);
-
- if(!c->inctx)
- c->inctx = xmalloc_and_zero(sizeof(*c->inctx));
-
- /* Convert the challenge from hexadecimal back to binary */
-
- hex2bin(buffer, buffer, len);
-
- /* Decrypt the meta key */
-
- if(RSA_private_decrypt(len, buffer, c->inkey, myself->connection->rsa_key, RSA_NO_PADDING) != len) { /* See challenge() */
- logger(DEBUG_ALWAYS, LOG_ERR, _("Error during encryption of meta key for %s (%s)"),
- c->name, c->hostname);
- return -1;
- }
-
- if(debug_level >= DEBUG_SCARY_THINGS) {
- bin2hex(c->inkey, buffer, len);
- buffer[len * 2] = '\0';
- logger(DEBUG_ALWAYS, LOG_DEBUG, _("Received random meta key (unencrypted): %s"), buffer);
- }
-
- /* All incoming requests will now be encrypted. */
-
- /* Check and lookup cipher and digest algorithms */
-
- if(cipher) {
- c->incipher = EVP_get_cipherbynid(cipher);
-
- if(!c->incipher) {
- logger(DEBUG_ALWAYS, LOG_ERR, _("%s (%s) uses unknown cipher!"), c->name, c->hostname);
- return -1;
- }
-
- EVP_DecryptInit(c->inctx, c->incipher,
- c->inkey + len - c->incipher->key_len,
- c->inkey + len - c->incipher->key_len -
- c->incipher->iv_len);
-
- c->status.decryptin = 1;
- } else {
- c->incipher = NULL;
- }
-
- c->inmaclength = maclength;
-
- if(digest) {
- c->indigest = EVP_get_digestbynid(digest);
-
- if(!c->indigest) {
- logger(DEBUG_ALWAYS, LOG_ERR, _("Node %s (%s) uses unknown digest!"), c->name, c->hostname);
- return -1;