/*
This file is part of GNUnet.
- (C) 2009, 2010, 2011, 2012 Christian Grothoff (and other contributing authors)
+ (C) 2009-2013 Christian Grothoff (and other contributing authors)
GNUnet is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published
#include "gnunet-service-core_neighbours.h"
#include "gnunet-service-core_sessions.h"
#include "gnunet_statistics_service.h"
-#include "gnunet_peerinfo_service.h"
-#include "gnunet_hello_lib.h"
#include "gnunet_constants.h"
#include "gnunet_signatures.h"
#include "gnunet_protocols.h"
#include "core.h"
-/**
- * Set to GNUNET_YES to perform some slightly expensive internal invariant checks.
- */
-#define EXTRA_CHECKS GNUNET_YES
-
/**
* How long do we wait for SET_KEY confirmation initially?
*/
-#define INITIAL_SET_KEY_RETRY_FREQUENCY GNUNET_TIME_relative_multiply (MAX_SET_KEY_DELAY, 1)
+#define INITIAL_SET_KEY_RETRY_FREQUENCY GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 10)
/**
* What is the minimum frequency for a PING message?
/**
* How often do we rekey?
*/
-#define REKEY_FREQUENCY GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 90)
+#define REKEY_FREQUENCY GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_HOURS, 12)
+/**
+ * What time difference do we tolerate?
+ */
+#define REKEY_TOLERANCE GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 5)
/**
* What is the maximum age of a message for us to consider processing
*/
#define MAX_MESSAGE_AGE GNUNET_TIME_UNIT_DAYS
+
+
+GNUNET_NETWORK_STRUCT_BEGIN
+
/**
- * What is the maximum delay for a SET_KEY message?
+ * Message transmitted with the signed ephemeral key of a peer. The
+ * session key is then derived from the two ephemeral keys (ECDHE).
*/
-#define MAX_SET_KEY_DELAY GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 10)
+struct EphemeralKeyMessage
+{
+
+ /**
+ * Message type is CORE_EPHEMERAL_KEY.
+ */
+ struct GNUNET_MessageHeader header;
+ /**
+ * Status of the sender (should be in "enum PeerStateMachine"), nbo.
+ */
+ int32_t sender_status GNUNET_PACKED;
+
+ /**
+ * An ECC signature of the 'origin' asserting the validity of
+ * the given ephemeral key.
+ */
+ struct GNUNET_CRYPTO_EddsaSignature signature;
+
+ /**
+ * Information about what is being signed.
+ */
+ struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
+
+ /**
+ * At what time was this key created (beginning of validity).
+ */
+ struct GNUNET_TIME_AbsoluteNBO creation_time;
+
+ /**
+ * When does the given ephemeral key expire (end of validity).
+ */
+ struct GNUNET_TIME_AbsoluteNBO expiration_time;
+
+ /**
+ * Ephemeral public ECC key (always for NIST P-521) encoded in a format suitable
+ * for network transmission as created using 'gcry_sexp_sprint'.
+ */
+ struct GNUNET_CRYPTO_EcdhePublicKey ephemeral_key;
+
+ /**
+ * Public key of the signing peer (persistent version, not the ephemeral public key).
+ */
+ struct GNUNET_PeerIdentity origin_identity;
+
+};
-GNUNET_NETWORK_STRUCT_BEGIN
/**
* We're sending an (encrypted) PING to the other peer to check if he
uint32_t challenge GNUNET_PACKED;
/**
- * Reserved, always 'GNUNET_BANDWIDTH_VALUE_MAX'.
+ * Reserved, always zero.
*/
- struct GNUNET_BANDWIDTH_Value32NBO reserved;
+ uint32_t reserved;
/**
* Intended target of the PING, used primarily to check
};
-/**
- * Message transmitted to set (or update) a session key.
- */
-struct SetKeyMessage
-{
-
- /**
- * Message type is either CORE_SET_KEY.
- */
- struct GNUNET_MessageHeader header;
-
- /**
- * Status of the sender (should be in "enum PeerStateMachine"), nbo.
- */
- int32_t sender_status GNUNET_PACKED;
-
- /**
- * Purpose of the signature, will be
- * GNUNET_SIGNATURE_PURPOSE_SET_KEY.
- */
- struct GNUNET_CRYPTO_RsaSignaturePurpose purpose;
-
- /**
- * At what time was this key created?
- */
- struct GNUNET_TIME_AbsoluteNBO creation_time;
-
- /**
- * The encrypted session key.
- */
- struct GNUNET_CRYPTO_RsaEncryptedData encrypted_key;
-
- /**
- * Who is the intended recipient?
- */
- struct GNUNET_PeerIdentity target;
-
- /**
- * Signature of the stuff above (starting at purpose).
- */
- struct GNUNET_CRYPTO_RsaSignature signature;
-
-};
-
-
/**
* Encapsulation for encrypted messages exchanged between
* peers. Followed by the actual encrypted data.
uint32_t sequence_number GNUNET_PACKED;
/**
- * Reserved, always 'GNUNET_BANDWIDTH_VALUE_MAX'.
+ * Reserved, always zero.
*/
- struct GNUNET_BANDWIDTH_Value32NBO reserved;
+ uint32_t reserved;
/**
* Timestamp. Used to prevent reply of ancient messages
KX_STATE_KEY_RECEIVED,
/**
- * The other peer has confirmed our session key with a message
- * encrypted with his session key (which we got). Key exchange
- * is done.
+ * The other peer has confirmed our session key + PING with a PONG
+ * message encrypted with his session key (which we got). Key
+ * exchange is done.
*/
KX_STATE_UP,
/**
- * We're rekeying, so we have received the other peer's session
- * key, but he didn't get ours yet.
- */
- KX_STATE_REKEY,
-
- /**
- * We're rekeying but have not yet received confirmation for our new
- * key from the other peer.
+ * We're rekeying (or had a timeout), so we have sent the other peer
+ * our new ephemeral key, but we did not get a matching PONG yet.
+ * This is equivalent to being 'KX_STATE_KEY_RECEIVED', except that
+ * the session is marked as 'up' with sessions (as we don't want to
+ * drop and re-establish P2P connections simply due to rekeying).
*/
KX_STATE_REKEY_SENT
+
};
*/
struct GSC_KeyExchangeInfo
{
- /**
- * Identity of the peer.
- */
- struct GNUNET_PeerIdentity peer;
-
- /**
- * SetKeyMessage to transmit (initialized the first
- * time our status goes past 'KX_STATE_KEY_SENT').
- */
- struct SetKeyMessage skm;
-
- /**
- * PING message we transmit to the other peer.
- */
- struct PingMessage ping;
/**
- * SetKeyMessage we received and did not process yet.
+ * DLL.
*/
- struct SetKeyMessage *skm_received;
+ struct GSC_KeyExchangeInfo *next;
/**
- * PING message we received from the other peer and
- * did not process yet (or NULL).
+ * DLL.
*/
- struct PingMessage *ping_received;
+ struct GSC_KeyExchangeInfo *prev;
/**
- * PONG message we received from the other peer and
- * did not process yet (or NULL).
- */
- struct PongMessage *pong_received;
-
- /**
- * Encrypted message we received from the other peer and
- * did not process yet (or NULL).
- */
- struct EncryptedMessage *emsg_received;
-
- /**
- * Non-NULL if we are currently looking up HELLOs for this peer.
- * for this peer.
- */
- struct GNUNET_PEERINFO_IteratorContext *pitr;
-
- /**
- * Public key of the neighbour, NULL if we don't have it yet.
+ * Identity of the peer.
*/
- struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *public_key;
+ struct GNUNET_PeerIdentity peer;
/**
- * We received a PONG message before we got the "public_key"
- * (or the SET_KEY). We keep it here until we have a key
- * to decrypt it. NULL if no PONG is pending.
+ * PING message we transmit to the other peer.
*/
- struct PongMessage *pending_pong;
+ struct PingMessage ping;
/**
* Key we use to encrypt our messages for the other peer
* (initialized by us when we do the handshake).
*/
- struct GNUNET_CRYPTO_AesSessionKey encrypt_key;
+ struct GNUNET_CRYPTO_SymmetricSessionKey encrypt_key;
/**
* Key we use to decrypt messages from the other peer
* (given to us by the other peer during the handshake).
*/
- struct GNUNET_CRYPTO_AesSessionKey decrypt_key;
-
- /**
- * At what time did we generate our encryption key?
- */
- struct GNUNET_TIME_Absolute encrypt_key_created;
+ struct GNUNET_CRYPTO_SymmetricSessionKey decrypt_key;
/**
* At what time did the other peer generate the decryption key?
*/
- struct GNUNET_TIME_Absolute decrypt_key_created;
+ struct GNUNET_TIME_Absolute foreign_key_expires;
/**
* When should the session time out (if there are no PONGs)?
/**
- * Handle to peerinfo service.
+ * Our private key.
*/
-static struct GNUNET_PEERINFO_Handle *peerinfo;
+static struct GNUNET_CRYPTO_EddsaPrivateKey *my_private_key;
/**
- * Our private key.
+ * Our ephemeral private key.
*/
-static struct GNUNET_CRYPTO_RsaPrivateKey *my_private_key;
+static struct GNUNET_CRYPTO_EcdhePrivateKey *my_ephemeral_key;
/**
- * Our public key.
+ * Current message we send for a key exchange.
*/
-static struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded my_public_key;
+static struct EphemeralKeyMessage current_ekm;
/**
* Our message stream tokenizer (for encrypted payload).
*/
static struct GNUNET_SERVER_MessageStreamTokenizer *mst;
-
-#if EXTRA_CHECKS
/**
- * Check internal invariants of the given KX record.
- *
- * @param kx record to check
- * @param file filename for error reporting
- * @param line line number for error reporting
- */
-static void
-check_kx_record (struct GSC_KeyExchangeInfo *kx,
- const char *file,
- int line)
-{
- struct GNUNET_HashCode hc;
-
- if (NULL == kx->public_key)
- return;
- GNUNET_CRYPTO_hash (kx->public_key, sizeof (*kx->public_key), &hc);
- GNUNET_assert_at (0 == memcmp (&hc, &kx->peer, sizeof (struct GNUNET_HashCode)), file, line);
-}
+ * DLL head.
+ */
+static struct GSC_KeyExchangeInfo *kx_head;
+/**
+ * DLL tail.
+ */
+static struct GSC_KeyExchangeInfo *kx_tail;
/**
- * Check internal invariants of the given KX record.
- *
- * @param kx record to check
+ * Task scheduled for periodic re-generation (and thus rekeying) of our
+ * ephemeral key.
*/
-#define CHECK_KX(kx) check_kx_record(kx, __FILE__, __LINE__)
-#else
-#define CHECK_KX(kx)
-#endif
+static GNUNET_SCHEDULER_TaskIdentifier rekey_task;
+
/**
* Derive an authentication key from "set key" information
* @param akey authentication key to derive
* @param skey session key to use
* @param seed seed to use
- * @param creation_time creation time to use
*/
static void
derive_auth_key (struct GNUNET_CRYPTO_AuthKey *akey,
- const struct GNUNET_CRYPTO_AesSessionKey *skey, uint32_t seed,
- struct GNUNET_TIME_Absolute creation_time)
+ const struct GNUNET_CRYPTO_SymmetricSessionKey *skey, uint32_t seed)
{
static const char ctx[] = "authentication key";
- struct GNUNET_TIME_AbsoluteNBO ctbe;
- ctbe = GNUNET_TIME_absolute_hton (creation_time);
- GNUNET_CRYPTO_hmac_derive_key (akey, skey, &seed, sizeof (seed), &skey->key,
- sizeof (skey->key), &ctbe, sizeof (ctbe), ctx,
- sizeof (ctx), NULL);
+ GNUNET_CRYPTO_hmac_derive_key (akey, skey,
+ &seed, sizeof (seed),
+ skey, sizeof (struct GNUNET_CRYPTO_SymmetricSessionKey),
+ ctx, sizeof (ctx),
+ NULL);
}
* @param identity identity of the other peer to use
*/
static void
-derive_iv (struct GNUNET_CRYPTO_AesInitializationVector *iv,
- const struct GNUNET_CRYPTO_AesSessionKey *skey, uint32_t seed,
+derive_iv (struct GNUNET_CRYPTO_SymmetricInitializationVector *iv,
+ const struct GNUNET_CRYPTO_SymmetricSessionKey *skey, uint32_t seed,
const struct GNUNET_PeerIdentity *identity)
{
static const char ctx[] = "initialization vector";
- GNUNET_CRYPTO_aes_derive_iv (iv, skey, &seed, sizeof (seed),
- &identity->hashPubKey.bits,
- sizeof (identity->hashPubKey.bits), ctx,
- sizeof (ctx), NULL);
+ GNUNET_CRYPTO_symmetric_derive_iv (iv, skey, &seed, sizeof (seed),
+ identity,
+ sizeof (struct GNUNET_PeerIdentity), ctx,
+ sizeof (ctx), NULL);
}
* @param identity identity of the other peer to use
*/
static void
-derive_pong_iv (struct GNUNET_CRYPTO_AesInitializationVector *iv,
- const struct GNUNET_CRYPTO_AesSessionKey *skey, uint32_t seed,
+derive_pong_iv (struct GNUNET_CRYPTO_SymmetricInitializationVector *iv,
+ const struct GNUNET_CRYPTO_SymmetricSessionKey *skey, uint32_t seed,
uint32_t challenge, const struct GNUNET_PeerIdentity *identity)
{
static const char ctx[] = "pong initialization vector";
- GNUNET_CRYPTO_aes_derive_iv (iv, skey, &seed, sizeof (seed),
- &identity->hashPubKey.bits,
- sizeof (identity->hashPubKey.bits), &challenge,
- sizeof (challenge), ctx, sizeof (ctx), NULL);
+ GNUNET_CRYPTO_symmetric_derive_iv (iv, skey, &seed, sizeof (seed),
+ identity,
+ sizeof (struct GNUNET_PeerIdentity),
+ &challenge, sizeof (challenge),
+ ctx, sizeof (ctx),
+ NULL);
+}
+
+
+/**
+ * Derive an AES key from key material
+ *
+ * @param sender peer identity of the sender
+ * @param receiver peer identity of the sender
+ * @param key_material high entropy key material to use
+ * @param skey set to derived session key
+ */
+static void
+derive_aes_key (const struct GNUNET_PeerIdentity *sender,
+ const struct GNUNET_PeerIdentity *receiver,
+ const struct GNUNET_HashCode *key_material,
+ struct GNUNET_CRYPTO_SymmetricSessionKey *skey)
+{
+ static const char ctx[] = "aes key generation vector";
+
+ GNUNET_CRYPTO_kdf (skey, sizeof (struct GNUNET_CRYPTO_SymmetricSessionKey),
+ ctx, sizeof (ctx),
+ key_material, sizeof (struct GNUNET_HashCode),
+ sender, sizeof (struct GNUNET_PeerIdentity),
+ receiver, sizeof (struct GNUNET_PeerIdentity),
+ NULL);
}
*/
static int
do_encrypt (struct GSC_KeyExchangeInfo *kx,
- const struct GNUNET_CRYPTO_AesInitializationVector *iv,
+ const struct GNUNET_CRYPTO_SymmetricInitializationVector *iv,
const void *in, void *out, size_t size)
{
if (size != (uint16_t) size)
return GNUNET_NO;
}
GNUNET_assert (size ==
- GNUNET_CRYPTO_aes_encrypt (in, (uint16_t) size,
+ GNUNET_CRYPTO_symmetric_encrypt (in, (uint16_t) size,
&kx->encrypt_key, iv, out));
GNUNET_STATISTICS_update (GSC_stats, gettext_noop ("# bytes encrypted"), size,
GNUNET_NO);
* @param iv initialization vector to use
* @param in ciphertext
* @param out plaintext
- * @param size size of in/out
- * @return GNUNET_OK on success
+ * @param size size of @a in / @a out
+ * @return #GNUNET_OK on success
*/
static int
do_decrypt (struct GSC_KeyExchangeInfo *kx,
- const struct GNUNET_CRYPTO_AesInitializationVector *iv,
+ const struct GNUNET_CRYPTO_SymmetricInitializationVector *iv,
const void *in, void *out, size_t size)
{
if (size != (uint16_t) size)
return GNUNET_NO;
}
if ( (kx->status != KX_STATE_KEY_RECEIVED) && (kx->status != KX_STATE_UP) &&
- (kx->status != KX_STATE_REKEY_SENT) &&
- (kx->status != KX_STATE_REKEY) )
+ (kx->status != KX_STATE_REKEY_SENT) )
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
if (size !=
- GNUNET_CRYPTO_aes_decrypt (in, (uint16_t) size, &kx->decrypt_key, iv,
+ GNUNET_CRYPTO_symmetric_decrypt (in, (uint16_t) size, &kx->decrypt_key, iv,
out))
{
GNUNET_break (0);
struct GSC_KeyExchangeInfo *kx = cls;
kx->retry_set_key_task = GNUNET_SCHEDULER_NO_TASK;
- kx->set_key_retry_frequency =
- GNUNET_TIME_relative_multiply (kx->set_key_retry_frequency, 2);
+ kx->set_key_retry_frequency = GNUNET_TIME_STD_BACKOFF (kx->set_key_retry_frequency);
+ GNUNET_assert (KX_STATE_DOWN != kx->status);
send_key (kx);
}
/**
- * PEERINFO is giving us a HELLO for a peer. Add the public key to
- * the neighbour's struct and continue with the key exchange. Or, if
- * we did not get a HELLO, just do nothing.
+ * Create a fresh PING message for transmission to the other peer.
*
- * @param cls the 'struct GSC_KeyExchangeInfo' to retry sending the key for
- * @param peer the peer for which this is the HELLO
- * @param hello HELLO message of that peer
- * @param err_msg NULL if successful, otherwise contains error message
+ * @param kx key exchange context to create PING for
*/
static void
-process_hello (void *cls, const struct GNUNET_PeerIdentity *peer,
- const struct GNUNET_HELLO_Message *hello, const char *err_msg)
+setup_fresh_ping (struct GSC_KeyExchangeInfo *kx)
{
- struct GSC_KeyExchangeInfo *kx = cls;
- struct SetKeyMessage *skm;
+ struct PingMessage pp;
+ struct PingMessage *pm;
+ struct GNUNET_CRYPTO_SymmetricInitializationVector iv;
- CHECK_KX (kx);
- if (NULL != err_msg)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- _("Error in communication with PEERINFO service\n"));
- kx->pitr = NULL;
- if (GNUNET_SCHEDULER_NO_TASK != kx->retry_set_key_task)
- GNUNET_SCHEDULER_cancel (kx->retry_set_key_task);
- kx->retry_set_key_task =
- GNUNET_SCHEDULER_add_delayed (kx->set_key_retry_frequency,
- &set_key_retry_task, kx);
- return;
- }
- if (NULL == peer)
- {
- kx->pitr = NULL;
- if (NULL != kx->public_key)
- return; /* done here */
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Failed to obtain public key for peer `%4s', delaying processing of SET_KEY\n",
- GNUNET_i2s (&kx->peer));
- GNUNET_STATISTICS_update (GSC_stats,
- gettext_noop
- ("# Delayed connecting due to lack of public key"),
- 1, GNUNET_NO);
- if (GNUNET_SCHEDULER_NO_TASK != kx->retry_set_key_task)
- GNUNET_SCHEDULER_cancel (kx->retry_set_key_task);
- kx->retry_set_key_task =
- GNUNET_SCHEDULER_add_delayed (kx->set_key_retry_frequency,
- &set_key_retry_task, kx);
- return;
- }
- GNUNET_break (0 == memcmp (peer, &kx->peer, sizeof (struct GNUNET_PeerIdentity)));
- if (NULL != kx->public_key)
- {
- /* already have public key, why are we here? */
- GNUNET_break (0);
- return;
- }
- GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == kx->retry_set_key_task);
- kx->public_key =
- GNUNET_malloc (sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded));
- if (GNUNET_OK != GNUNET_HELLO_get_key (hello, kx->public_key))
- {
- GNUNET_break (0);
- GNUNET_free (kx->public_key);
- kx->public_key = NULL;
- CHECK_KX (kx);
- return;
- }
- CHECK_KX (kx);
- send_key (kx);
- if (NULL != kx->skm_received)
- {
- skm = kx->skm_received;
- kx->skm_received = NULL;
- GSC_KX_handle_set_key (kx, &skm->header);
- GNUNET_free (skm);
- }
+ pm = &kx->ping;
+ pm->header.size = htons (sizeof (struct PingMessage));
+ pm->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_PING);
+ pm->iv_seed =
+ GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
+ derive_iv (&iv, &kx->encrypt_key, pm->iv_seed, &kx->peer);
+ pp.challenge = kx->ping_challenge;
+ pp.target = kx->peer;
+ do_encrypt (kx, &iv, &pp.target, &pm->target,
+ sizeof (struct PingMessage) - ((void *) &pm->target -
+ (void *) pm));
}
GSC_KX_start (const struct GNUNET_PeerIdentity *pid)
{
struct GSC_KeyExchangeInfo *kx;
+ struct GNUNET_HashCode h1;
+ struct GNUNET_HashCode h2;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Initiating key exchange with `%s'\n",
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Initiating key exchange with `%s'\n",
GNUNET_i2s (pid));
GNUNET_STATISTICS_update (GSC_stats,
gettext_noop ("# key exchanges initiated"), 1,
GNUNET_NO);
- kx = GNUNET_malloc (sizeof (struct GSC_KeyExchangeInfo));
+ kx = GNUNET_new (struct GSC_KeyExchangeInfo);
kx->peer = *pid;
kx->set_key_retry_frequency = INITIAL_SET_KEY_RETRY_FREQUENCY;
- kx->pitr =
- GNUNET_PEERINFO_iterate (peerinfo, pid,
- GNUNET_TIME_UNIT_FOREVER_REL /* timeout? */ ,
- &process_hello, kx);
- CHECK_KX (kx);
+ GNUNET_CONTAINER_DLL_insert (kx_head,
+ kx_tail,
+ kx);
+ GNUNET_CRYPTO_hash (pid, sizeof (struct GNUNET_PeerIdentity), &h1);
+ GNUNET_CRYPTO_hash (&GSC_my_identity, sizeof (struct GNUNET_PeerIdentity), &h2);
+
+ kx->status = KX_STATE_KEY_SENT;
+ if (0 < GNUNET_CRYPTO_hash_cmp (&h1,
+ &h2))
+ {
+ /* peer with "lower" identity starts KX, otherwise we typically end up
+ with both peers starting the exchange and transmit the 'set key'
+ message twice */
+ send_key (kx);
+ }
+ else
+ {
+ /* peer with "higher" identity starts a delayed KX, if the "lower" peer
+ * does not start a KX since he sees no reasons to do so */
+ kx->retry_set_key_task = GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS,
+ &set_key_retry_task, kx);
+ }
return kx;
}
void
GSC_KX_stop (struct GSC_KeyExchangeInfo *kx)
{
+ GSC_SESSIONS_end (&kx->peer);
GNUNET_STATISTICS_update (GSC_stats, gettext_noop ("# key exchanges stopped"),
1, GNUNET_NO);
- if (NULL != kx->pitr)
- {
- GNUNET_PEERINFO_iterate_cancel (kx->pitr);
- kx->pitr = NULL;
- }
if (kx->retry_set_key_task != GNUNET_SCHEDULER_NO_TASK)
{
GNUNET_SCHEDULER_cancel (kx->retry_set_key_task);
GNUNET_SCHEDULER_cancel (kx->keep_alive_task);
kx->keep_alive_task = GNUNET_SCHEDULER_NO_TASK;
}
- GNUNET_free_non_null (kx->skm_received);
- GNUNET_free_non_null (kx->ping_received);
- GNUNET_free_non_null (kx->pong_received);
- GNUNET_free_non_null (kx->emsg_received);
- GNUNET_free_non_null (kx->public_key);
+ GNUNET_CONTAINER_DLL_remove (kx_head,
+ kx_tail,
+ kx);
GNUNET_free (kx);
}
+/**
+ * Send our PING to the other peer.
+ *
+ * @param kx key exchange context
+ */
+static void
+send_ping (struct GSC_KeyExchangeInfo *kx)
+{
+ GSC_NEIGHBOURS_transmit (&kx->peer, &kx->ping.header,
+ MIN_PING_FREQUENCY);
+}
+
/**
* We received a SET_KEY message. Validate and update
* our key material and status.
* @param msg the set key message we received
*/
void
-GSC_KX_handle_set_key (struct GSC_KeyExchangeInfo *kx,
- const struct GNUNET_MessageHeader *msg)
+GSC_KX_handle_ephemeral_key (struct GSC_KeyExchangeInfo *kx,
+ const struct GNUNET_MessageHeader *msg)
{
- const struct SetKeyMessage *m;
- struct GNUNET_TIME_Absolute t;
- struct GNUNET_CRYPTO_AesSessionKey k;
- struct PingMessage *ping;
- struct PongMessage *pong;
+ const struct EphemeralKeyMessage *m;
+ struct GNUNET_TIME_Absolute start_t;
+ struct GNUNET_TIME_Absolute end_t;
+ struct GNUNET_TIME_Absolute now;
enum KxStateMachine sender_status;
uint16_t size;
-
- CHECK_KX (kx);
+ struct GNUNET_HashCode key_material;
+
size = ntohs (msg->size);
- if (size != sizeof (struct SetKeyMessage))
+ if (sizeof (struct EphemeralKeyMessage) != size)
{
GNUNET_break_op (0);
return;
}
- m = (const struct SetKeyMessage *) msg;
- GNUNET_STATISTICS_update (GSC_stats, gettext_noop ("# session keys received"),
+ m = (const struct EphemeralKeyMessage *) msg;
+ end_t = GNUNET_TIME_absolute_ntoh (m->expiration_time);
+ if ( ( (KX_STATE_KEY_RECEIVED == kx->status) ||
+ (KX_STATE_UP == kx->status) ||
+ (KX_STATE_REKEY_SENT == kx->status) ) &&
+ (end_t.abs_value_us <= kx->foreign_key_expires.abs_value_us) )
+ {
+ GNUNET_STATISTICS_update (GSC_stats, gettext_noop ("# old ephemeral keys ignored"),
+ 1, GNUNET_NO);
+ return;
+ }
+ start_t = GNUNET_TIME_absolute_ntoh (m->creation_time);
+
+ GNUNET_STATISTICS_update (GSC_stats, gettext_noop ("# ephemeral keys received"),
1, GNUNET_NO);
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Core service receives `%s' request from `%4s'.\n", "SET_KEY",
+ "Core service receives `%s' request from `%4s'.\n", "EPHEMERAL_KEY",
GNUNET_i2s (&kx->peer));
- if (NULL == kx->public_key)
- {
- GNUNET_free_non_null (kx->skm_received);
- kx->skm_received = (struct SetKeyMessage *) GNUNET_copy_message (msg);
- return;
- }
if (0 !=
- memcmp (&m->target, &GSC_my_identity,
+ memcmp (&m->origin_identity,
+ &kx->peer.public_key,
sizeof (struct GNUNET_PeerIdentity)))
{
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- _("`%s' is for `%s', not for me. Ignoring.\n"), "SET_KEY",
- GNUNET_i2s (&m->target));
+ GNUNET_break_op (0);
return;
}
if ((ntohl (m->purpose.size) !=
- sizeof (struct GNUNET_CRYPTO_RsaSignaturePurpose) +
+ sizeof (struct GNUNET_CRYPTO_EccSignaturePurpose) +
+ sizeof (struct GNUNET_TIME_AbsoluteNBO) +
sizeof (struct GNUNET_TIME_AbsoluteNBO) +
- sizeof (struct GNUNET_CRYPTO_RsaEncryptedData) +
- sizeof (struct GNUNET_PeerIdentity)) ||
+ sizeof (struct GNUNET_CRYPTO_EddsaPublicKey) +
+ sizeof (struct GNUNET_CRYPTO_EddsaPublicKey)) ||
(GNUNET_OK !=
- GNUNET_CRYPTO_rsa_verify (GNUNET_SIGNATURE_PURPOSE_SET_KEY, &m->purpose,
- &m->signature, kx->public_key)))
+ GNUNET_CRYPTO_eddsa_verify (GNUNET_SIGNATURE_PURPOSE_SET_ECC_KEY,
+ &m->purpose,
+ &m->signature, &m->origin_identity.public_key)))
{
/* invalid signature */
- CHECK_KX (kx);
GNUNET_break_op (0);
return;
}
- t = GNUNET_TIME_absolute_ntoh (m->creation_time);
- if (((kx->status == KX_STATE_KEY_RECEIVED) || (kx->status == KX_STATE_UP)) &&
- (t.abs_value < kx->decrypt_key_created.abs_value))
+ now = GNUNET_TIME_absolute_get ();
+ if ( (end_t.abs_value_us < GNUNET_TIME_absolute_subtract (now, REKEY_TOLERANCE).abs_value_us) ||
+ (start_t.abs_value_us > GNUNET_TIME_absolute_add (now, REKEY_TOLERANCE).abs_value_us) )
{
- /* this could rarely happen due to massive re-ordering of
- * messages on the network level, but is most likely either
- * a bug or some adversary messing with us. Report. */
- GNUNET_break_op (0);
+ GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+ _("Ephemeral key message from peer `%s' rejected as its validity range does not match our system time (%llu not in [%llu,%llu]).\n"),
+ GNUNET_i2s (&kx->peer),
+ now.abs_value_us,
+ start_t.abs_value_us,
+ end_t.abs_value_us);
return;
}
- if ((GNUNET_CRYPTO_rsa_decrypt
- (my_private_key, &m->encrypted_key, &k,
- sizeof (struct GNUNET_CRYPTO_AesSessionKey)) !=
- sizeof (struct GNUNET_CRYPTO_AesSessionKey)) ||
- (GNUNET_OK != GNUNET_CRYPTO_aes_check_session_key (&k)))
+ if (GNUNET_OK !=
+ GNUNET_CRYPTO_ecc_ecdh (my_ephemeral_key,
+ &m->ephemeral_key,
+ &key_material))
{
- /* failed to decrypt !? */
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
- "Invalid key %x decrypted by %s from message %u (origin: %s)\n",
- (unsigned int) GNUNET_CRYPTO_crc32_n (&k, sizeof (struct GNUNET_CRYPTO_AesSessionKey)),
- GNUNET_i2s (&GSC_my_identity),
- (unsigned int) GNUNET_CRYPTO_crc32_n (&m->encrypted_key, sizeof (struct GNUNET_CRYPTO_RsaEncryptedData)),
- GNUNET_h2s (&kx->peer.hashPubKey));
- GNUNET_break_op (0);
+ GNUNET_break (0);
return;
}
GNUNET_STATISTICS_update (GSC_stats,
- gettext_noop ("# SET_KEY messages decrypted"), 1,
+ gettext_noop ("# EPHEMERAL_KEY messages decrypted"), 1,
GNUNET_NO);
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Received SET_KEY from `%s'\n",
- GNUNET_i2s (&kx->peer));
- kx->decrypt_key = k;
- if (kx->decrypt_key_created.abs_value != t.abs_value)
+ derive_aes_key (&GSC_my_identity,
+ &kx->peer,
+ &key_material,
+ &kx->encrypt_key);
+ derive_aes_key (&kx->peer,
+ &GSC_my_identity,
+ &key_material,
+ &kx->decrypt_key);
+ /* fresh key, reset sequence numbers */
+ kx->last_sequence_number_received = 0;
+ kx->last_packets_bitmap = 0;
+ kx->foreign_key_expires = end_t;
+ setup_fresh_ping (kx);
+
+ /* check if we still need to send the sender our key */
+ sender_status = (enum KxStateMachine) ntohl (m->sender_status);
+ switch (sender_status)
{
- /* fresh key, reset sequence numbers */
- kx->last_sequence_number_received = 0;
- kx->last_packets_bitmap = 0;
- kx->decrypt_key_created = t;
+ case KX_STATE_DOWN:
+ GNUNET_break_op (0);
+ break;
+ case KX_STATE_KEY_SENT:
+ /* fine, need to send our key after updating our status, see below */
+ break;
+ case KX_STATE_KEY_RECEIVED:
+ case KX_STATE_UP:
+ case KX_STATE_REKEY_SENT:
+ /* other peer already got our key */
+ break;
+ default:
+ GNUNET_break (0);
+ break;
}
- sender_status = (enum KxStateMachine) ntohl (m->sender_status);
+ /* check if we need to confirm everything is fine via PING + PONG */
switch (kx->status)
{
case KX_STATE_DOWN:
+ GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == kx->keep_alive_task);
kx->status = KX_STATE_KEY_RECEIVED;
- /* we're not up, so we are already doing 'send_key' */
+ if (KX_STATE_KEY_SENT == sender_status)
+ send_key (kx);
+ send_ping (kx);
break;
case KX_STATE_KEY_SENT:
+ GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == kx->keep_alive_task);
kx->status = KX_STATE_KEY_RECEIVED;
- /* we're not up, so we are already doing 'send_key' */
+ if (KX_STATE_KEY_SENT == sender_status)
+ send_key (kx);
+ send_ping (kx);
break;
case KX_STATE_KEY_RECEIVED:
- /* we're not up, so we are already doing 'send_key' */
- break;
- case KX_STATE_UP:
- if ((sender_status == KX_STATE_DOWN) ||
- (sender_status == KX_STATE_KEY_SENT))
- send_key (kx); /* we are up, but other peer is not! */
+ GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == kx->keep_alive_task);
+ if (KX_STATE_KEY_SENT == sender_status)
+ send_key (kx);
+ send_ping (kx);
break;
- case KX_STATE_REKEY:
- if ((sender_status == KX_STATE_DOWN) ||
- (sender_status == KX_STATE_KEY_SENT))
- send_key (kx); /* we are up, but other peer is not! */
+ case KX_STATE_UP:
+ kx->status = KX_STATE_REKEY_SENT;
+ if (KX_STATE_KEY_SENT == sender_status)
+ send_key (kx);
+ /* we got a new key, need to reconfirm! */
+ send_ping (kx);
break;
case KX_STATE_REKEY_SENT:
- if ((sender_status == KX_STATE_DOWN) ||
- (sender_status == KX_STATE_KEY_SENT))
- send_key (kx); /* we are up, but other peer is not! */
+ if (KX_STATE_KEY_SENT == sender_status)
+ send_key (kx);
+ /* we got a new key, need to reconfirm! */
+ send_ping (kx);
break;
default:
GNUNET_break (0);
break;
}
- if (NULL != kx->ping_received)
- {
- ping = kx->ping_received;
- kx->ping_received = NULL;
- GSC_KX_handle_ping (kx, &ping->header);
- GNUNET_free (ping);
- }
- if (NULL != kx->pong_received)
- {
- pong = kx->pong_received;
- kx->pong_received = NULL;
- GSC_KX_handle_pong (kx, &pong->header);
- GNUNET_free (pong);
- }
}
struct PingMessage t;
struct PongMessage tx;
struct PongMessage tp;
- struct GNUNET_CRYPTO_AesInitializationVector iv;
+ struct GNUNET_CRYPTO_SymmetricInitializationVector iv;
uint16_t msize;
msize = ntohs (msg->size);
GNUNET_STATISTICS_update (GSC_stats,
gettext_noop ("# PING messages received"), 1,
GNUNET_NO);
- if ((kx->status != KX_STATE_KEY_RECEIVED) && (kx->status != KX_STATE_UP) &&
- (kx->status != KX_STATE_REKEY_SENT))
+ if ( (kx->status != KX_STATE_KEY_RECEIVED) &&
+ (kx->status != KX_STATE_UP) &&
+ (kx->status != KX_STATE_REKEY_SENT))
{
- /* defer */
- GNUNET_free_non_null (kx->ping_received);
- kx->ping_received = (struct PingMessage *) GNUNET_copy_message (msg);
+ /* ignore */
+ GNUNET_STATISTICS_update (GSC_stats,
+ gettext_noop ("# PING messages dropped (out of order)"), 1,
+ GNUNET_NO);
return;
}
m = (const struct PingMessage *) msg;
GNUNET_break_op (0);
return;
}
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Received PING from `%s'\n",
- GNUNET_i2s (&kx->peer));
/* construct PONG */
- tx.reserved = GNUNET_BANDWIDTH_VALUE_MAX;
+ tx.reserved = 0;
tx.challenge = t.challenge;
tx.target = t.target;
tp.header.type = htons (GNUNET_MESSAGE_TYPE_CORE_PONG);
}
-/**
- * Create a fresh SET KEY message for transmission to the other peer.
- * Also creates a new key.
- *
- * @param kx key exchange context to create SET KEY message for
- */
-static void
-setup_fresh_setkey (struct GSC_KeyExchangeInfo *kx)
-{
- struct SetKeyMessage *skm;
-
- GNUNET_CRYPTO_aes_create_session_key (&kx->encrypt_key);
- kx->encrypt_key_created = GNUNET_TIME_absolute_get ();
- skm = &kx->skm;
- skm->header.size = htons (sizeof (struct SetKeyMessage));
- skm->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_SET_KEY);
- skm->purpose.size =
- htonl (sizeof (struct GNUNET_CRYPTO_RsaSignaturePurpose) +
- sizeof (struct GNUNET_TIME_AbsoluteNBO) +
- sizeof (struct GNUNET_CRYPTO_RsaEncryptedData) +
- sizeof (struct GNUNET_PeerIdentity));
- skm->purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_SET_KEY);
- skm->creation_time = GNUNET_TIME_absolute_hton (kx->encrypt_key_created);
- skm->target = kx->peer;
- CHECK_KX (kx);
- GNUNET_assert (GNUNET_OK ==
- GNUNET_CRYPTO_rsa_encrypt (&kx->encrypt_key,
- sizeof (struct
- GNUNET_CRYPTO_AesSessionKey),
- kx->public_key,
- &skm->encrypted_key));
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Encrypting key %x for %s resulting in message %u (origin: %s)\n",
- (unsigned int) GNUNET_CRYPTO_crc32_n (&kx->encrypt_key, sizeof (struct GNUNET_CRYPTO_AesSessionKey)),
- GNUNET_i2s (&kx->peer),
- (unsigned int) GNUNET_CRYPTO_crc32_n (&skm->encrypted_key, sizeof (struct GNUNET_CRYPTO_RsaEncryptedData)),
- GNUNET_h2s (&GSC_my_identity.hashPubKey));
-
- GNUNET_assert (GNUNET_OK ==
- GNUNET_CRYPTO_rsa_sign (my_private_key, &skm->purpose,
- &skm->signature));
-}
-
-
-/**
- * Create a fresh PING message for transmission to the other peer.
- *
- * @param kx key exchange context to create PING for
- */
-static void
-setup_fresh_ping (struct GSC_KeyExchangeInfo *kx)
-{
- struct PingMessage pp;
- struct PingMessage *pm;
- struct GNUNET_CRYPTO_AesInitializationVector iv;
-
- pm = &kx->ping;
- pm->header.size = htons (sizeof (struct PingMessage));
- pm->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_PING);
- pm->iv_seed =
- GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
- derive_iv (&iv, &kx->encrypt_key, pm->iv_seed, &kx->peer);
- pp.challenge = kx->ping_challenge;
- pp.target = kx->peer;
- do_encrypt (kx, &iv, &pp.target, &pm->target,
- sizeof (struct PingMessage) - ((void *) &pm->target -
- (void *) pm));
-}
-
-
/**
* Task triggered when a neighbour entry is about to time out
* (and we should prevent this by sending a PING).
kx->keep_alive_task = GNUNET_SCHEDULER_NO_TASK;
left = GNUNET_TIME_absolute_get_remaining (kx->timeout);
- if (0 == left.rel_value)
+ if (0 == left.rel_value_us)
{
GNUNET_STATISTICS_update (GSC_stats,
gettext_noop ("# sessions terminated by timeout"),
1, GNUNET_NO);
GSC_SESSIONS_end (&kx->peer);
- kx->status = KX_STATE_DOWN;
+ kx->status = KX_STATE_KEY_SENT;
send_key (kx);
return;
}
}
-/**
- * Trigger rekeying event.
- *
- * @param cls the 'struct GSC_KeyExchangeInfo'
- * @param tc schedule context (unused)
- */
-static void
-trigger_rekey (void *cls,
- const struct GNUNET_SCHEDULER_TaskContext *tc)
-{
- struct GSC_KeyExchangeInfo *kx = cls;
-
- GNUNET_break (KX_STATE_UP == kx->status);
- kx->status = KX_STATE_REKEY;
- kx->set_key_retry_frequency = INITIAL_SET_KEY_RETRY_FREQUENCY;
- kx->retry_set_key_task =
- GNUNET_SCHEDULER_add_delayed (kx->set_key_retry_frequency,
- &set_key_retry_task, kx);
-}
-
-
-/**
- * Schedule rekey operation.
- *
- * @param kx key exchange to schedule rekey for
- */
-static void
-schedule_rekey (struct GSC_KeyExchangeInfo *kx)
-{
- struct GNUNET_TIME_Relative rdelay;
-
- if (GNUNET_SCHEDULER_NO_TASK != kx->retry_set_key_task)
- GNUNET_SCHEDULER_cancel (kx->retry_set_key_task);
- rdelay = REKEY_FREQUENCY;
- /* randomize rekey frequency by one minute to avoid synchronization */
- rdelay.rel_value += GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
- 60 * 1000);
- kx->retry_set_key_task = GNUNET_SCHEDULER_add_delayed (REKEY_FREQUENCY,
- &trigger_rekey,
- kx);
-}
-
-
/**
* We received a PONG message. Validate and update our status.
*
{
const struct PongMessage *m;
struct PongMessage t;
- struct EncryptedMessage *emsg;
- struct GNUNET_CRYPTO_AesInitializationVector iv;
+ struct GNUNET_CRYPTO_SymmetricInitializationVector iv;
uint16_t msize;
msize = ntohs (msg->size);
switch (kx->status)
{
case KX_STATE_DOWN:
+ GNUNET_STATISTICS_update (GSC_stats,
+ gettext_noop ("# PONG messages dropped (connection down)"), 1,
+ GNUNET_NO);
return;
case KX_STATE_KEY_SENT:
- GNUNET_free_non_null (kx->pong_received);
- kx->pong_received = (struct PongMessage *) GNUNET_copy_message (msg);
+ GNUNET_STATISTICS_update (GSC_stats,
+ gettext_noop ("# PONG messages dropped (out of order)"), 1,
+ GNUNET_NO);
return;
case KX_STATE_KEY_RECEIVED:
break;
case KX_STATE_UP:
break;
- case KX_STATE_REKEY:
- break;
case KX_STATE_REKEY_SENT:
break;
default:
}
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Received PONG from `%s'\n",
GNUNET_i2s (&kx->peer));
+ /* no need to resend key any longer */
+ if (GNUNET_SCHEDULER_NO_TASK != kx->retry_set_key_task)
+ {
+ GNUNET_SCHEDULER_cancel (kx->retry_set_key_task);
+ kx->retry_set_key_task = GNUNET_SCHEDULER_NO_TASK;
+ }
switch (kx->status)
{
case KX_STATE_DOWN:
- GNUNET_break (0); /* should be impossible */
+ GNUNET_assert (0); /* should be impossible */
return;
case KX_STATE_KEY_SENT:
- GNUNET_break (0); /* should be impossible */
+ GNUNET_assert (0); /* should be impossible */
return;
case KX_STATE_KEY_RECEIVED:
GNUNET_STATISTICS_update (GSC_stats,
GNUNET_NO);
kx->status = KX_STATE_UP;
GSC_SESSIONS_create (&kx->peer, kx);
- CHECK_KX (kx);
- schedule_rekey (kx);
GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == kx->keep_alive_task);
- if (NULL != kx->emsg_received)
- {
- emsg = kx->emsg_received;
- kx->emsg_received = NULL;
- GSC_KX_handle_encrypted_message (kx, &emsg->header, NULL,
- 0 /* FIXME: ATSI */ );
- GNUNET_free (emsg);
- }
update_timeout (kx);
break;
case KX_STATE_UP:
- update_timeout (kx);
- break;
- case KX_STATE_REKEY:
+ GNUNET_STATISTICS_update (GSC_stats,
+ gettext_noop
+ ("# timeouts prevented via PONG"), 1,
+ GNUNET_NO);
update_timeout (kx);
break;
case KX_STATE_REKEY_SENT:
("# rekey operations confirmed via PONG"), 1,
GNUNET_NO);
kx->status = KX_STATE_UP;
- schedule_rekey (kx);
update_timeout (kx);
break;
default:
/**
- * Send our key (and encrypted PING) to the other peer.
+ * Send our key to the other peer.
*
* @param kx key exchange context
*/
static void
send_key (struct GSC_KeyExchangeInfo *kx)
{
- CHECK_KX (kx);
+ GNUNET_assert (KX_STATE_DOWN != kx->status);
if (GNUNET_SCHEDULER_NO_TASK != kx->retry_set_key_task)
{
GNUNET_SCHEDULER_cancel (kx->retry_set_key_task);
kx->retry_set_key_task = GNUNET_SCHEDULER_NO_TASK;
}
- if (KX_STATE_UP == kx->status)
- return; /* nothing to do */
- if (NULL == kx->public_key)
- {
- if (NULL != kx->pitr)
- return;
- /* lookup public key, then try again */
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Trying to obtain public key for `%s'\n",
- GNUNET_i2s (&kx->peer));
- kx->pitr =
- GNUNET_PEERINFO_iterate (peerinfo, &kx->peer,
- GNUNET_TIME_UNIT_FOREVER_REL /* timeout? */ ,
- &process_hello, kx);
- return;
- }
-
- /* update status */
- switch (kx->status)
- {
- case KX_STATE_DOWN:
- kx->status = KX_STATE_KEY_SENT;
- /* setup SET KEY message */
- setup_fresh_setkey (kx);
- setup_fresh_ping (kx);
- GNUNET_STATISTICS_update (GSC_stats,
- gettext_noop
- ("# SET_KEY and PING messages created"), 1,
- GNUNET_NO);
- break;
- case KX_STATE_KEY_SENT:
- break;
- case KX_STATE_KEY_RECEIVED:
- break;
- case KX_STATE_UP:
- GNUNET_break (0);
- return;
- case KX_STATE_REKEY:
- kx->status = KX_STATE_REKEY_SENT;
- /* setup fresh SET KEY message */
- setup_fresh_setkey (kx);
- setup_fresh_ping (kx);
- GNUNET_STATISTICS_update (GSC_stats,
- gettext_noop
- ("# SET_KEY and PING messages created"), 1,
- GNUNET_NO);
- GNUNET_STATISTICS_update (GSC_stats,
- gettext_noop
- ("# REKEY operations performed"), 1,
- GNUNET_NO);
- break;
- case KX_STATE_REKEY_SENT:
- break;
- default:
- GNUNET_break (0);
- return;
- }
-
/* always update sender status in SET KEY message */
- /* Not sending rekey sent state to be compatible with GNUnet 0.9.2 */
- kx->skm.sender_status = htonl ((int32_t) ((kx->status == KX_STATE_REKEY_SENT) ?
- KX_STATE_KEY_RECEIVED : kx->status));
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Sending SET_KEY and PING to `%s'\n",
- GNUNET_i2s (&kx->peer));
- GSC_NEIGHBOURS_transmit (&kx->peer, &kx->skm.header,
- kx->set_key_retry_frequency);
- GSC_NEIGHBOURS_transmit (&kx->peer, &kx->ping.header,
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Sending key to `%s' (my status: %d)\n",
+ GNUNET_i2s (&kx->peer),
+ kx->status);
+ current_ekm.sender_status = htonl ((int32_t) (kx->status));
+ GSC_NEIGHBOURS_transmit (&kx->peer, ¤t_ekm.header,
kx->set_key_retry_frequency);
kx->retry_set_key_task =
GNUNET_SCHEDULER_add_delayed (kx->set_key_retry_frequency,
char cbuf[used]; /* ciphertext */
struct EncryptedMessage *em; /* encrypted message */
struct EncryptedMessage *ph; /* plaintext header */
- struct GNUNET_CRYPTO_AesInitializationVector iv;
+ struct GNUNET_CRYPTO_SymmetricInitializationVector iv;
struct GNUNET_CRYPTO_AuthKey auth_key;
ph = (struct EncryptedMessage *) pbuf;
htonl (GNUNET_CRYPTO_random_u32
(GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX));
ph->sequence_number = htonl (++kx->last_sequence_number_sent);
- ph->reserved = GNUNET_BANDWIDTH_VALUE_MAX;
+ ph->reserved = 0;
ph->timestamp = GNUNET_TIME_absolute_hton (GNUNET_TIME_absolute_get ());
memcpy (&ph[1], payload, payload_size);
used - ENCRYPTED_HEADER_SIZE));
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Encrypted %u bytes for %s\n",
used - ENCRYPTED_HEADER_SIZE, GNUNET_i2s (&kx->peer));
- derive_auth_key (&auth_key, &kx->encrypt_key, ph->iv_seed,
- kx->encrypt_key_created);
+ derive_auth_key (&auth_key,
+ &kx->encrypt_key,
+ ph->iv_seed);
GNUNET_CRYPTO_hmac (&auth_key, &em->sequence_number,
used - ENCRYPTED_HEADER_SIZE, &em->hmac);
GSC_NEIGHBOURS_transmit (&kx->peer, &em->header,
{
/**
- * Performance information for the connection.
+ * Key exchange context.
*/
- const struct GNUNET_ATS_Information *atsi;
+ struct GSC_KeyExchangeInfo *kx;
/**
* Sender of the message.
*/
const struct GNUNET_PeerIdentity *peer;
-
- /**
- * Number of entries in 'atsi' array.
- */
- uint32_t atsi_count;
};
*
* @param kx key exchange context for encrypting the message
* @param msg encrypted message
- * @param atsi performance data
- * @param atsi_count number of entries in ats (excluding 0-termination)
*/
void
GSC_KX_handle_encrypted_message (struct GSC_KeyExchangeInfo *kx,
- const struct GNUNET_MessageHeader *msg,
- const struct GNUNET_ATS_Information *atsi,
- uint32_t atsi_count)
+ const struct GNUNET_MessageHeader *msg)
{
const struct EncryptedMessage *m;
struct EncryptedMessage *pt; /* plaintext */
struct GNUNET_HashCode ph;
uint32_t snum;
struct GNUNET_TIME_Absolute t;
- struct GNUNET_CRYPTO_AesInitializationVector iv;
+ struct GNUNET_CRYPTO_SymmetricInitializationVector iv;
struct GNUNET_CRYPTO_AuthKey auth_key;
struct DeliverMessageContext dmc;
uint16_t size = ntohs (msg->size);
return;
}
m = (const struct EncryptedMessage *) msg;
- if ((kx->status != KX_STATE_KEY_RECEIVED) && (kx->status != KX_STATE_UP) &&
- (kx->status != KX_STATE_REKEY_SENT) )
+ if (kx->status != KX_STATE_UP)
{
GNUNET_STATISTICS_update (GSC_stats,
gettext_noop
- ("# failed to decrypt message (no session key)"),
+ ("# DATA message dropped (out of order)"),
1, GNUNET_NO);
return;
}
- if (KX_STATE_KEY_RECEIVED == kx->status)
+ if (0 == GNUNET_TIME_absolute_get_remaining (kx->foreign_key_expires).rel_value_us)
{
- /* defer */
- GNUNET_free_non_null (kx->emsg_received);
- kx->emsg_received = (struct EncryptedMessage *) GNUNET_copy_message (msg);
+ GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+ _("Session to peer `%s' went down due to key expiration (should not happen)\n"),
+ GNUNET_i2s (&kx->peer));
+ GNUNET_STATISTICS_update (GSC_stats,
+ gettext_noop ("# sessions terminated by key expiration"),
+ 1, GNUNET_NO);
+ GSC_SESSIONS_end (&kx->peer);
+ if (GNUNET_SCHEDULER_NO_TASK != kx->keep_alive_task)
+ {
+ GNUNET_SCHEDULER_cancel (kx->keep_alive_task);
+ kx->keep_alive_task = GNUNET_SCHEDULER_NO_TASK;
+ }
+ kx->status = KX_STATE_KEY_SENT;
+ send_key (kx);
return;
}
+
/* validate hash */
- derive_auth_key (&auth_key, &kx->decrypt_key, m->iv_seed,
- kx->decrypt_key_created);
+ derive_auth_key (&auth_key, &kx->decrypt_key, m->iv_seed);
GNUNET_CRYPTO_hmac (&auth_key, &m->sequence_number,
size - ENCRYPTED_HEADER_SIZE, &ph);
if (0 != memcmp (&ph, &m->hmac, sizeof (struct GNUNET_HashCode)))
{
/* checksum failed */
- GNUNET_break_op (0);
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Failed checksum validation for a message from `%s'\n",
+ GNUNET_i2s (&kx->peer));
return;
}
derive_iv (&iv, &kx->decrypt_key, m->iv_seed, &GSC_my_identity);
snum = ntohl (pt->sequence_number);
if (kx->last_sequence_number_received == snum)
{
- GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Received duplicate message, ignoring.\n");
/* duplicate, ignore */
GNUNET_STATISTICS_update (GSC_stats,
if ((kx->last_sequence_number_received > snum) &&
(kx->last_sequence_number_received - snum > 32))
{
- GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Received ancient out of sequence message, ignoring.\n");
/* ancient out of sequence, ignore */
GNUNET_STATISTICS_update (GSC_stats,
if ((kx->last_packets_bitmap & rotbit) != 0)
{
- GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Received duplicate message, ignoring.\n");
GNUNET_STATISTICS_update (GSC_stats,
gettext_noop ("# bytes dropped (duplicates)"),
/* check timestamp */
t = GNUNET_TIME_absolute_ntoh (pt->timestamp);
- if (GNUNET_TIME_absolute_get_duration (t).rel_value >
- MAX_MESSAGE_AGE.rel_value)
+ if (GNUNET_TIME_absolute_get_duration (t).rel_value_us >
+ MAX_MESSAGE_AGE.rel_value_us)
{
- GNUNET_log (GNUNET_ERROR_TYPE_INFO,
- _("Message received far too old (%llu ms). Content ignored.\n"),
- GNUNET_TIME_absolute_get_duration (t).rel_value);
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Message received far too old (%s). Content ignored.\n",
+ GNUNET_STRINGS_relative_time_to_string (GNUNET_TIME_absolute_get_duration (t), GNUNET_YES));
GNUNET_STATISTICS_update (GSC_stats,
gettext_noop
("# bytes dropped (ancient message)"), size,
GNUNET_STATISTICS_update (GSC_stats,
gettext_noop ("# bytes of payload decrypted"),
size - sizeof (struct EncryptedMessage), GNUNET_NO);
- dmc.atsi = atsi;
- dmc.atsi_count = atsi_count;
+ dmc.kx = kx;
dmc.peer = &kx->peer;
if (GNUNET_OK !=
GNUNET_SERVER_mst_receive (mst, &dmc,
{
struct DeliverMessageContext *dmc = client;
+ if (KX_STATE_UP != dmc->kx->status)
+ {
+ GNUNET_STATISTICS_update (GSC_stats,
+ gettext_noop
+ ("# PAYLOAD dropped (out of order)"),
+ 1, GNUNET_NO);
+ return GNUNET_OK;
+ }
switch (ntohs (m->type))
{
case GNUNET_MESSAGE_TYPE_CORE_BINARY_TYPE_MAP:
GSC_SESSIONS_set_typemap (dmc->peer, m);
return GNUNET_OK;
default:
- GSC_CLIENTS_deliver_message (dmc->peer, dmc->atsi, dmc->atsi_count, m,
+ GSC_CLIENTS_deliver_message (dmc->peer, m,
ntohs (m->size),
GNUNET_CORE_OPTION_SEND_FULL_INBOUND);
- GSC_CLIENTS_deliver_message (dmc->peer, dmc->atsi, dmc->atsi_count, m,
+ GSC_CLIENTS_deliver_message (dmc->peer, m,
sizeof (struct GNUNET_MessageHeader),
GNUNET_CORE_OPTION_SEND_HDR_INBOUND);
}
}
+/**
+ * Setup the message that links the ephemeral key to our persistent
+ * public key and generate the appropriate signature.
+ */
+static void
+sign_ephemeral_key ()
+{
+ current_ekm.header.size = htons (sizeof (struct EphemeralKeyMessage));
+ current_ekm.header.type = htons (GNUNET_MESSAGE_TYPE_CORE_EPHEMERAL_KEY);
+ current_ekm.sender_status = 0; /* to be set later */
+ current_ekm.purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_SET_ECC_KEY);
+ current_ekm.purpose.size = htonl (sizeof (struct GNUNET_CRYPTO_EccSignaturePurpose) +
+ sizeof (struct GNUNET_TIME_AbsoluteNBO) +
+ sizeof (struct GNUNET_TIME_AbsoluteNBO) +
+ sizeof (struct GNUNET_CRYPTO_EcdhePublicKey) +
+ sizeof (struct GNUNET_PeerIdentity));
+ current_ekm.creation_time = GNUNET_TIME_absolute_hton (GNUNET_TIME_absolute_get ());
+ if (GNUNET_YES ==
+ GNUNET_CONFIGURATION_get_value_yesno (GSC_cfg,
+ "core",
+ "USE_EPHEMERAL_KEYS"))
+ {
+ current_ekm.expiration_time = GNUNET_TIME_absolute_hton (GNUNET_TIME_relative_to_absolute (GNUNET_TIME_relative_add (REKEY_FREQUENCY,
+ REKEY_TOLERANCE)));
+ }
+ else
+ {
+ current_ekm.expiration_time = GNUNET_TIME_absolute_hton (GNUNET_TIME_UNIT_FOREVER_ABS);
+ }
+ GNUNET_CRYPTO_ecdhe_key_get_public (my_ephemeral_key,
+ ¤t_ekm.ephemeral_key);
+ current_ekm.origin_identity = GSC_my_identity;
+ GNUNET_assert (GNUNET_OK ==
+ GNUNET_CRYPTO_eddsa_sign (my_private_key,
+ ¤t_ekm.purpose,
+ ¤t_ekm.signature));
+}
+
+
+/**
+ * Task run to trigger rekeying.
+ *
+ * @param cls closure, NULL
+ * @param tc scheduler context
+ */
+static void
+do_rekey (void *cls,
+ const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ struct GSC_KeyExchangeInfo *pos;
+
+ rekey_task = GNUNET_SCHEDULER_add_delayed (REKEY_FREQUENCY,
+ &do_rekey,
+ NULL);
+ if (NULL != my_ephemeral_key)
+ GNUNET_free (my_ephemeral_key);
+ my_ephemeral_key = GNUNET_CRYPTO_ecdhe_key_create ();
+ GNUNET_assert (NULL != my_ephemeral_key);
+ sign_ephemeral_key ();
+ for (pos = kx_head; NULL != pos; pos = pos->next)
+ {
+ pos->status = KX_STATE_REKEY_SENT;
+ send_key (pos);
+ }
+}
+
+
/**
* Initialize KX subsystem.
*
* @param pk private key to use for the peer
- * @return GNUNET_OK on success, GNUNET_SYSERR on failure
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on failure
*/
int
-GSC_KX_init (struct GNUNET_CRYPTO_RsaPrivateKey *pk)
+GSC_KX_init (struct GNUNET_CRYPTO_EddsaPrivateKey *pk)
{
+ GNUNET_assert (NULL != pk);
my_private_key = pk;
- GNUNET_CRYPTO_rsa_key_get_public (my_private_key, &my_public_key);
- GNUNET_CRYPTO_hash (&my_public_key, sizeof (my_public_key),
- &GSC_my_identity.hashPubKey);
- peerinfo = GNUNET_PEERINFO_connect (GSC_cfg);
- if (NULL == peerinfo)
+ GNUNET_CRYPTO_eddsa_key_get_public (my_private_key,
+ &GSC_my_identity.public_key);
+ my_ephemeral_key = GNUNET_CRYPTO_ecdhe_key_create ();
+ if (NULL == my_ephemeral_key)
{
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
- _("Could not access PEERINFO service. Exiting.\n"));
- GNUNET_CRYPTO_rsa_key_free (my_private_key);
+ GNUNET_break (0);
+ GNUNET_free (my_private_key);
my_private_key = NULL;
return GNUNET_SYSERR;
}
+ sign_ephemeral_key ();
+ rekey_task = GNUNET_SCHEDULER_add_delayed (REKEY_FREQUENCY,
+ &do_rekey,
+ NULL);
mst = GNUNET_SERVER_mst_create (&deliver_message, NULL);
return GNUNET_OK;
}
void
GSC_KX_done ()
{
- if (NULL != my_private_key)
+ if (GNUNET_SCHEDULER_NO_TASK != rekey_task)
{
- GNUNET_CRYPTO_rsa_key_free (my_private_key);
- my_private_key = NULL;
+ GNUNET_SCHEDULER_cancel (rekey_task);
+ rekey_task = GNUNET_SCHEDULER_NO_TASK;
+ }
+ if (NULL != my_ephemeral_key)
+ {
+ GNUNET_free (my_ephemeral_key);
+ my_ephemeral_key = NULL;
}
- if (NULL != peerinfo)
+ if (NULL != my_private_key)
{
- GNUNET_PEERINFO_disconnect (peerinfo);
- peerinfo = NULL;
+ GNUNET_free (my_private_key);
+ my_private_key = NULL;
}
if (NULL != mst)
{