#include "system.h"
+#include <openssl/sha.h>
+#include <openssl/rand.h>
+#include <openssl/err.h>
+#include <openssl/evp.h>
+
#include "splay_tree.h"
#include "conf.h"
#include "connection.h"
-#include "crypto.h"
#include "edge.h"
#include "graph.h"
#include "logger.h"
#include "netutl.h"
#include "node.h"
#include "protocol.h"
-#include "rsa.h"
#include "utils.h"
#include "xalloc.h"
bool send_id(connection_t *c) {
cp();
+ gettimeofday(&c->start, NULL);
+
return send_request(c, "%d %s %d", ID, myself->connection->name,
myself->connection->protocol_version);
}
}
bool send_metakey(connection_t *c) {
- size_t len = rsa_size(&c->rsa);
- char key[len];
- char enckey[len];
- char hexkey[2 * len + 1];
+ char *buffer;
+ int len;
+ bool x;
cp();
- if(!cipher_open_blowfish_ofb(&c->outcipher))
- return false;
+ len = RSA_size(c->rsa_key);
+
+ /* Allocate buffers for the meta key */
+
+ buffer = alloca(2 * len + 1);
- if(!digest_open_sha1(&c->outdigest))
- return false;
+ if(!c->outkey)
+ c->outkey = xmalloc(len);
- /* Create a random key */
+ if(!c->outctx)
+ c->outctx = xmalloc_and_zero(sizeof(*c->outctx));
+ cp();
+ /* Copy random data to the buffer */
- randomize(key, len);
+ RAND_pseudo_bytes((unsigned char *)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:
This can be done by setting the most significant bit to zero.
*/
- key[0] &= 0x7F;
-
- cipher_set_key_from_rsa(&c->outcipher, key, len, true);
+ c->outkey[0] &= 0x7F;
ifdebug(SCARY_THINGS) {
- bin2hex(key, hexkey, len);
- hexkey[len * 2] = '\0';
- logger(LOG_DEBUG, _("Generated random meta key (unencrypted): %s"), hexkey);
+ bin2hex(c->outkey, buffer, len);
+ buffer[len * 2] = '\0';
+ logger(LOG_DEBUG, _("Generated random meta key (unencrypted): %s"),
+ buffer);
}
/* Encrypt the random data
with a length equal to that of the modulus of the RSA key.
*/
- if(!rsa_public_encrypt(&c->rsa, key, len, enckey)) {
- logger(LOG_ERR, _("Error during encryption of meta key for %s (%s)"), c->name, c->hostname);
+ if(RSA_public_encrypt(len, (unsigned char *)c->outkey, (unsigned char *)buffer, c->rsa_key, RSA_NO_PADDING) != len) {
+ logger(LOG_ERR, _("Error during encryption of meta key for %s (%s)"),
+ c->name, c->hostname);
return false;
}
/* Convert the encrypted random data to a hexadecimal formatted string */
- bin2hex(enckey, hexkey, len);
- hexkey[len * 2] = '\0';
+ bin2hex(buffer, buffer, len);
+ buffer[len * 2] = '\0';
/* Send the meta key */
- bool result = send_request(c, "%d %d %d %d %d %s", METAKEY,
- cipher_get_nid(&c->outcipher),
- digest_get_nid(&c->outdigest), c->outmaclength,
- c->outcompression, hexkey);
-
- c->status.encryptout = true;
- return result;
+ 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) {
+ if(!EVP_EncryptInit(c->outctx, c->outcipher,
+ (unsigned char *)c->outkey + len - c->outcipher->key_len,
+ (unsigned char *)c->outkey + len - c->outcipher->key_len -
+ c->outcipher->iv_len)) {
+ logger(LOG_ERR, _("Error during initialisation of cipher for %s (%s): %s"),
+ c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL));
+ return false;
+ }
+
+ c->status.encryptout = true;
+ }
+
+ return x;
}
bool metakey_h(connection_t *c, char *request) {
- char hexkey[MAX_STRING_SIZE];
+ char buffer[MAX_STRING_SIZE];
int cipher, digest, maclength, compression;
- size_t len = rsa_size(&myself->connection->rsa);
- char enckey[len];
- char key[len];
+ int len;
cp();
- if(sscanf(request, "%*d %d %d %d %d " MAX_STRING, &cipher, &digest, &maclength, &compression, hexkey) != 5) {
- logger(LOG_ERR, _("Got bad %s from %s (%s)"), "METAKEY", c->name, c->hostname);
+ if(sscanf(request, "%*d %d %d %d %d " MAX_STRING, &cipher, &digest, &maclength, &compression, buffer) != 5) {
+ logger(LOG_ERR, _("Got bad %s from %s (%s)"), "METAKEY", c->name,
+ c->hostname);
return false;
}
+ len = RSA_size(myself->connection->rsa_key);
+
/* Check if the length of the meta key is all right */
- if(strlen(hexkey) != len * 2) {
+ if(strlen(buffer) != len * 2) {
logger(LOG_ERR, _("Possible intruder %s (%s): %s"), c->name, c->hostname, "wrong keylength");
return false;
}
+ /* 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(hexkey, enckey, len);
+ hex2bin(buffer, buffer, len);
/* Decrypt the meta key */
- if(!rsa_private_decrypt(&myself->connection->rsa, enckey, len, key)) {
- logger(LOG_ERR, _("Error during encryption of meta key for %s (%s)"), c->name, c->hostname);
+ if(RSA_private_decrypt(len, (unsigned char *)buffer, (unsigned char *)c->inkey, myself->connection->rsa_key, RSA_NO_PADDING) != len) { /* See challenge() */
+ logger(LOG_ERR, _("Error during encryption of meta key for %s (%s)"),
+ c->name, c->hostname);
return false;
}
ifdebug(SCARY_THINGS) {
- bin2hex(key, hexkey, len);
- hexkey[len * 2] = '\0';
- logger(LOG_DEBUG, _("Received random meta key (unencrypted): %s"), hexkey);
+ bin2hex(c->inkey, buffer, len);
+ buffer[len * 2] = '\0';
+ logger(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_open_by_nid(&c->incipher, cipher) || !cipher_set_key_from_rsa(&c->incipher, key, len, false)) {
- logger(LOG_ERR, _("Error during initialisation of cipher from %s (%s)"), c->name, c->hostname);
- return false;
+ if(cipher) {
+ c->incipher = EVP_get_cipherbynid(cipher);
+
+ if(!c->incipher) {
+ logger(LOG_ERR, _("%s (%s) uses unknown cipher!"), c->name, c->hostname);
+ return false;
+ }
+
+ if(!EVP_DecryptInit(c->inctx, c->incipher,
+ (unsigned char *)c->inkey + len - c->incipher->key_len,
+ (unsigned char *)c->inkey + len - c->incipher->key_len -
+ c->incipher->iv_len)) {
+ logger(LOG_ERR, _("Error during initialisation of cipher from %s (%s): %s"),
+ c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL));
+ return false;
+ }
+
+ c->status.decryptin = true;
+ } else {
+ c->incipher = NULL;
}
- if(!digest_open_by_nid(&c->indigest, digest)) {
- logger(LOG_ERR, _("Error during initialisation of digest from %s (%s)"), c->name, c->hostname);
- return false;
+ c->inmaclength = maclength;
+
+ if(digest) {
+ c->indigest = EVP_get_digestbynid(digest);
+
+ if(!c->indigest) {
+ logger(LOG_ERR, _("Node %s (%s) uses unknown digest!"), c->name, c->hostname);
+ return false;
+ }
+
+ if(c->inmaclength > c->indigest->md_size || c->inmaclength < 0) {
+ logger(LOG_ERR, _("%s (%s) uses bogus MAC length!"), c->name, c->hostname);
+ return false;
+ }
+ } else {
+ c->indigest = NULL;
}
- c->status.decryptin = true;
+ c->incompression = compression;
c->allow_request = CHALLENGE;
}
bool send_challenge(connection_t *c) {
- size_t len = rsa_size(&c->rsa);
- char buffer[len * 2 + 1];
+ char *buffer;
+ int len;
cp();
+ /* CHECKME: what is most reasonable value for len? */
+
+ len = RSA_size(c->rsa_key);
+
+ /* Allocate buffers for the challenge */
+
+ buffer = alloca(2 * len + 1);
+
if(!c->hischallenge)
c->hischallenge = xmalloc(len);
/* Copy random data to the buffer */
- randomize(c->hischallenge, len);
+ RAND_pseudo_bytes((unsigned char *)c->hischallenge, len);
/* Convert to hex */
bool challenge_h(connection_t *c, char *request) {
char buffer[MAX_STRING_SIZE];
- size_t len = rsa_size(&myself->connection->rsa);
- size_t digestlen = digest_length(&c->outdigest);
- char digest[digestlen];
+ int len;
cp();
if(sscanf(request, "%*d " MAX_STRING, buffer) != 1) {
- logger(LOG_ERR, _("Got bad %s from %s (%s)"), "CHALLENGE", c->name, c->hostname);
+ logger(LOG_ERR, _("Got bad %s from %s (%s)"), "CHALLENGE", c->name,
+ c->hostname);
return false;
}
+ len = RSA_size(myself->connection->rsa_key);
+
/* Check if the length of the challenge is all right */
if(strlen(buffer) != len * 2) {
- logger(LOG_ERR, _("Possible intruder %s (%s): %s"), c->name, c->hostname, "wrong challenge length");
+ logger(LOG_ERR, _("Possible intruder %s (%s): %s"), c->name,
+ c->hostname, "wrong challenge length");
return false;
}
+ /* Allocate buffers for the challenge */
+
+ if(!c->mychallenge)
+ c->mychallenge = xmalloc(len);
+
/* Convert the challenge from hexadecimal back to binary */
- hex2bin(buffer, buffer, len);
+ hex2bin(buffer, c->mychallenge, len);
c->allow_request = CHAL_REPLY;
+ /* Rest is done by send_chal_reply() */
+
+ return send_chal_reply(c);
+}
+
+bool send_chal_reply(connection_t *c) {
+ char hash[EVP_MAX_MD_SIZE * 2 + 1];
+ EVP_MD_CTX ctx;
+
cp();
/* Calculate the hash from the challenge we received */
- digest_create(&c->indigest, buffer, len, digest);
+ if(!EVP_DigestInit(&ctx, c->indigest)
+ || !EVP_DigestUpdate(&ctx, c->mychallenge, RSA_size(myself->connection->rsa_key))
+ || !EVP_DigestFinal(&ctx, (unsigned char *)hash, NULL)) {
+ logger(LOG_ERR, _("Error during calculation of response for %s (%s): %s"),
+ c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL));
+ return false;
+ }
/* Convert the hash to a hexadecimal formatted string */
- bin2hex(digest, buffer, digestlen);
- buffer[digestlen * 2] = '\0';
+ bin2hex(hash, hash, c->indigest->md_size);
+ hash[c->indigest->md_size * 2] = '\0';
/* Send the reply */
- return send_request(c, "%d %s", CHAL_REPLY, buffer);
+ return send_request(c, "%d %s", CHAL_REPLY, hash);
}
bool chal_reply_h(connection_t *c, char *request) {
char hishash[MAX_STRING_SIZE];
+ char myhash[EVP_MAX_MD_SIZE];
+ EVP_MD_CTX ctx;
cp();
/* Check if the length of the hash is all right */
- if(strlen(hishash) != digest_length(&c->outdigest) * 2) {
- logger(LOG_ERR, _("Possible intruder %s (%s): %s"), c->name, c->hostname, _("wrong challenge reply length"));
+ if(strlen(hishash) != c->outdigest->md_size * 2) {
+ logger(LOG_ERR, _("Possible intruder %s (%s): %s"), c->name,
+ c->hostname, _("wrong challenge reply length"));
return false;
}
/* Convert the hash to binary format */
- hex2bin(hishash, hishash, digest_length(&c->outdigest));
+ hex2bin(hishash, hishash, c->outdigest->md_size);
+
+ /* Calculate the hash from the challenge we sent */
+
+ if(!EVP_DigestInit(&ctx, c->outdigest)
+ || !EVP_DigestUpdate(&ctx, c->hischallenge, RSA_size(c->rsa_key))
+ || !EVP_DigestFinal(&ctx, (unsigned char *)myhash, NULL)) {
+ logger(LOG_ERR, _("Error during calculation of response from %s (%s): %s"),
+ c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL));
+ return false;
+ }
+
+ /* Verify the incoming hash with the calculated hash */
- /* Verify the hash */
+ if(memcmp(hishash, myhash, c->outdigest->md_size)) {
+ logger(LOG_ERR, _("Possible intruder %s (%s): %s"), c->name,
+ c->hostname, _("wrong challenge reply"));
+
+ ifdebug(SCARY_THINGS) {
+ bin2hex(myhash, hishash, SHA_DIGEST_LENGTH);
+ hishash[SHA_DIGEST_LENGTH * 2] = '\0';
+ logger(LOG_DEBUG, _("Expected challenge reply: %s"), hishash);
+ }
- if(!digest_verify(&c->outdigest, c->hischallenge, rsa_size(&c->rsa), hishash)) {
- logger(LOG_ERR, _("Possible intruder %s (%s): %s"), c->name, c->hostname, _("wrong challenge reply"));
return false;
}
Send an acknowledgement with the rest of the information needed.
*/
- free(c->hischallenge);
c->allow_request = ACK;
return send_ack(c);