return status;
}
-/* Receives Key Exchange Payload from responder consisting responders
- public key, f, and signature. This function verifies the public key,
- computes the secret shared key and verifies the signature. */
+/* An initiator finish final callback that is called to indicate that
+ the SKE protocol may continue. */
-SilcSKEStatus silc_ske_initiator_finish(SilcSKE ske,
- SilcBuffer ke_payload,
- SilcSKEVerifyCb verify_key,
- void *verify_context,
- SilcSKECb callback,
- void *context)
+typedef struct {
+ SilcSKECb callback;
+ void *context;
+} *SKEInitiatorFinish;
+
+static void silc_ske_initiator_finish_final(SilcSKE ske,
+ SilcSKEStatus status,
+ void *context)
{
- SilcSKEStatus status = SILC_SKE_STATUS_OK;
- SilcSKEKEPayload *payload;
- SilcPublicKey public_key = NULL;
- SilcInt *KEY;
+ SKEInitiatorFinish finish = (SKEInitiatorFinish)context;
+ SilcSKEKEPayload *payload = ske->ke2_payload;
unsigned char hash[32];
uint32 hash_len;
+ SilcPublicKey public_key = NULL;
- SILC_LOG_DEBUG(("Start"));
+ /* If the caller returns PENDING status SKE library will assume that
+ the caller will re-call this callback when it is not anymore in
+ PENDING status. */
+ if (status == SILC_SKE_STATUS_PENDING)
+ return;
- /* Decode the payload */
- status = silc_ske_payload_ke_decode(ske, ke_payload, &payload);
+ /* If the status is an error then the public key that was verified
+ by the caller is not authentic. */
if (status != SILC_SKE_STATUS_OK) {
ske->status = status;
- return status;
+ if (finish->callback)
+ finish->callback(ske, finish->context);
+ silc_free(finish);
+ return;
}
- ske->ke2_payload = payload;
-
- SILC_LOG_DEBUG(("Computing KEY = f ^ x mod p"));
- /* Compute the shared secret key */
- KEY = silc_calloc(1, sizeof(*KEY));
- silc_mp_init(KEY);
- silc_mp_powm(KEY, &payload->x, ske->x, &ske->prop->group->group);
- ske->KEY = KEY;
-
- if (payload->pk_data) {
- SILC_LOG_DEBUG(("Verifying public key"));
-
- if (!silc_pkcs_public_key_decode(payload->pk_data, payload->pk_len,
- &public_key)) {
- status = SILC_SKE_STATUS_UNSUPPORTED_PUBLIC_KEY;
- goto err;
- }
+ /* Decode the public key */
+ if (!silc_pkcs_public_key_decode(payload->pk_data, payload->pk_len,
+ &public_key)) {
+ status = SILC_SKE_STATUS_UNSUPPORTED_PUBLIC_KEY;
+ if (finish->callback)
+ finish->callback(ske, finish->context);
+ silc_free(finish);
+ return;
}
- if (verify_key) {
- status = (*verify_key)(ske, payload->pk_data, payload->pk_len,
- payload->pk_type, verify_context);
- if (status != SILC_SKE_STATUS_OK)
- goto err;
-
- SILC_LOG_DEBUG(("Public key is authentic"));
- }
+ SILC_LOG_DEBUG(("Public key is authentic"));
if (payload->pk_data) {
/* Compute the hash value */
memset(hash, 'F', hash_len);
}
- /* Call the callback. */
- if (callback)
- (*callback)(ske, context);
+ ske->status = SILC_SKE_STATUS_OK;
- return status;
+ /* Call the callback. The caller may now continue the SKE protocol. */
+ if (finish->callback)
+ finish->callback(ske, finish->context);
+
+ silc_free(finish);
+ return;
err:
memset(hash, 'F', sizeof(hash));
ske->hash = NULL;
}
+ if (status == SILC_SKE_STATUS_OK)
+ ske->status = SILC_SKE_STATUS_ERROR;
+
+ ske->status = status;
+
+ /* Call the callback. */
+ if (finish->callback)
+ finish->callback(ske, finish->context);
+ silc_free(finish);
+}
+
+/* Receives Key Exchange Payload from responder consisting responders
+ public key, f, and signature. This function verifies the public key,
+ computes the secret shared key and verifies the signature.
+
+ The `callback' will be called to indicate that the caller may
+ continue with the SKE protocol. The caller must not continue
+ before the SKE libary has called that callback. If this function
+ returns an error the callback will not be called. It is called
+ if this function return SILC_SKE_STATUS_OK or SILC_SKE_STATUS_PENDING.
+ However, note that when the library calls the callback the ske->status
+ may be error.
+
+ This calls the `verify_key' callback to verify the received public
+ key or certificate. If the `verify_key' is provided then the remote
+ must send public key and it is considered to be an error if remote
+ does not send its public key. If caller is performing a re-key with
+ SKE then the `verify_key' is usually not provided when it is not also
+ required for the remote to send its public key. */
+
+SilcSKEStatus silc_ske_initiator_finish(SilcSKE ske,
+ SilcBuffer ke_payload,
+ SilcSKEVerifyCb verify_key,
+ void *verify_context,
+ SilcSKECb callback,
+ void *context)
+{
+ SilcSKEStatus status = SILC_SKE_STATUS_OK;
+ SilcSKEKEPayload *payload;
+ SilcInt *KEY;
+ SKEInitiatorFinish finish;
+
+ SILC_LOG_DEBUG(("Start"));
+
+ /* Decode the payload */
+ status = silc_ske_payload_ke_decode(ske, ke_payload, &payload);
+ if (status != SILC_SKE_STATUS_OK) {
+ ske->status = status;
+ return status;
+ }
+ ske->ke2_payload = payload;
+
+ if (!payload->pk_data && verify_key) {
+ SILC_LOG_DEBUG(("Remote end did not send its public key (or certificate), "
+ "even though we require it"));
+ ske->status = SILC_SKE_STATUS_PUBLIC_KEY_NOT_PROVIDED;
+ goto err;
+ }
+
+ SILC_LOG_DEBUG(("Computing KEY = f ^ x mod p"));
+
+ /* Compute the shared secret key */
+ KEY = silc_calloc(1, sizeof(*KEY));
+ silc_mp_init(KEY);
+ silc_mp_powm(KEY, &payload->x, ske->x, &ske->prop->group->group);
+ ske->KEY = KEY;
+
+ finish = silc_calloc(1, sizeof(*finish));
+ finish->callback = callback;
+ finish->context = context;
+
+ if (verify_key) {
+ SILC_LOG_DEBUG(("Verifying public key"));
+
+ (*verify_key)(ske, payload->pk_data, payload->pk_len,
+ payload->pk_type, verify_context,
+ silc_ske_initiator_finish_final, finish);
+
+ /* We will continue to the final state after the public key has
+ been verified by the caller. */
+ return SILC_SKE_STATUS_PENDING;
+ }
+
+ /* Continue to final state */
+ silc_ske_initiator_finish_final(ske, SILC_SKE_STATUS_OK, finish);
+
+ return SILC_SKE_STATUS_OK;
+
+ err:
+ silc_ske_payload_ke_free(payload);
+ ske->ke2_payload = NULL;
+
+ silc_mp_clear(ske->KEY);
+ silc_free(ske->KEY);
+ ske->KEY = NULL;
+
if (status == SILC_SKE_STATUS_OK)
return SILC_SKE_STATUS_ERROR;
return status;
}
-/* This function receives the Key Exchange Payload from the initiator.
- This also performs the mutual authentication if required. Then, this
- function first generated a random number x, such that 1 < x < q
- and computes f = g ^ x mod p. This then puts the result f to a Key
- Exchange Payload. */
+/* An responder phase 2 final callback that is called to indicate that
+ the SKE protocol may continue. */
-SilcSKEStatus silc_ske_responder_phase_2(SilcSKE ske,
- SilcBuffer ke_payload,
- SilcSKEVerifyCb verify_key,
- void *verify_context,
- SilcSKECb callback,
- void *context)
+typedef struct {
+ SilcSKECb callback;
+ void *context;
+} *SKEResponderPhaseII;
+
+static void silc_ske_responder_phase2_final(SilcSKE ske,
+ SilcSKEStatus status,
+ void *context)
{
- SilcSKEStatus status = SILC_SKE_STATUS_OK;
+ SKEResponderPhaseII finish = (SKEResponderPhaseII)context;
SilcSKEKEPayload *recv_payload, *send_payload;
SilcInt *x, f;
- SILC_LOG_DEBUG(("Start"));
+ recv_payload = ske->ke1_payload;
- /* Decode Key Exchange Payload */
- status = silc_ske_payload_ke_decode(ske, ke_payload, &recv_payload);
+ /* If the caller returns PENDING status SKE library will assume that
+ the caller will re-call this callback when it is not anymore in
+ PENDING status. */
+ if (status == SILC_SKE_STATUS_PENDING)
+ return;
+
+ /* If the status is an error then the public key that was verified
+ by the caller is not authentic. */
if (status != SILC_SKE_STATUS_OK) {
ske->status = status;
- return status;
+ if (finish->callback)
+ finish->callback(ske, finish->context);
+ silc_free(finish);
+ return;
}
- ske->ke1_payload = recv_payload;
-
- /* Verify the received public key and verify the signature if we are
- doing mutual authentication. */
+ /* The public key verification was performed only if the Mutual
+ Authentication flag is set. */
if (ske->start_payload &&
ske->start_payload->flags & SILC_SKE_SP_FLAG_MUTUAL) {
SilcPublicKey public_key = NULL;
unsigned char hash[32];
uint32 hash_len;
- SILC_LOG_DEBUG(("We are doing mutual authentication"));
- SILC_LOG_DEBUG(("Verifying public key"));
-
+ /* Decode the public key */
if (!silc_pkcs_public_key_decode(recv_payload->pk_data,
recv_payload->pk_len,
&public_key)) {
- status = SILC_SKE_STATUS_UNSUPPORTED_PUBLIC_KEY;
- return status;
- }
-
- if (verify_key) {
- status = (*verify_key)(ske, recv_payload->pk_data, recv_payload->pk_len,
- recv_payload->pk_type, verify_context);
- if (status != SILC_SKE_STATUS_OK)
- return status;
+ ske->status = SILC_SKE_STATUS_UNSUPPORTED_PUBLIC_KEY;
+ if (finish->callback)
+ finish->callback(ske, finish->context);
+ silc_free(finish);
+ return;
}
SILC_LOG_DEBUG(("Public key is authentic"));
/* Compute the hash value */
status = silc_ske_make_hash(ske, hash, &hash_len, TRUE);
- if (status != SILC_SKE_STATUS_OK)
- return status;
+ if (status != SILC_SKE_STATUS_OK) {
+ ske->status = status;
+ if (finish->callback)
+ finish->callback(ske, finish->context);
+ silc_free(finish);
+ return;
+ }
SILC_LOG_DEBUG(("Verifying signature (HASH_i)"));
SILC_LOG_DEBUG(("Signature don't match"));
- status = SILC_SKE_STATUS_INCORRECT_SIGNATURE;
- return status;
+ ske->status = SILC_SKE_STATUS_INCORRECT_SIGNATURE;
+ if (finish->callback)
+ finish->callback(ske, finish->context);
+ silc_free(finish);
+ return;
}
SILC_LOG_DEBUG(("Signature is Ok"));
if (status != SILC_SKE_STATUS_OK) {
silc_mp_clear(x);
silc_free(x);
- return status;
+ ske->status = status;
+ if (finish->callback)
+ finish->callback(ske, finish->context);
+ silc_free(finish);
+ return;
}
SILC_LOG_DEBUG(("Computing f = g ^ x mod p"));
ske->x = x;
ske->ke2_payload = send_payload;
- /* Call the callback. */
- if (callback)
- (*callback)(ske, context);
+ /* Call the callback. The caller may now continue with the SKE protocol. */
+ ske->status = SILC_SKE_STATUS_OK;
+ if (finish->callback)
+ finish->callback(ske, finish->context);
+ silc_free(finish);
+}
- return status;
+/* This function receives the Key Exchange Payload from the initiator.
+ This also performs the mutual authentication if required. Then, this
+ function first generated a random number x, such that 1 < x < q
+ and computes f = g ^ x mod p. This then puts the result f to a Key
+ Exchange Payload.
+
+ The `callback' will be called to indicate that the caller may
+ continue with the SKE protocol. The caller must not continue
+ before the SKE libary has called that callback. If this function
+ returns an error the callback will not be called. It is called
+ if this function return SILC_SKE_STATUS_OK or SILC_SKE_STATUS_PENDING.
+ However, note that when the library calls the callback the ske->status
+ may be error.
+
+ This calls the `verify_key' callback to verify the received public
+ key or certificate if the Mutual Authentication flag is set. If the
+ `verify_key' is provided then the remote must send public key and it
+ is considered to be an error if remote does not send its public key. */
+
+SilcSKEStatus silc_ske_responder_phase_2(SilcSKE ske,
+ SilcBuffer ke_payload,
+ SilcSKEVerifyCb verify_key,
+ void *verify_context,
+ SilcSKECb callback,
+ void *context)
+{
+ SilcSKEStatus status = SILC_SKE_STATUS_OK;
+ SilcSKEKEPayload *recv_payload;
+ SKEResponderPhaseII finish;
+
+ SILC_LOG_DEBUG(("Start"));
+
+ /* Decode Key Exchange Payload */
+ status = silc_ske_payload_ke_decode(ske, ke_payload, &recv_payload);
+ if (status != SILC_SKE_STATUS_OK) {
+ ske->status = status;
+ return status;
+ }
+
+ ske->ke1_payload = recv_payload;
+
+ finish = silc_calloc(1, sizeof(*finish));
+ finish->callback = callback;
+ finish->context = context;
+
+ /* Verify the received public key and verify the signature if we are
+ doing mutual authentication. */
+ if (ske->start_payload &&
+ ske->start_payload->flags & SILC_SKE_SP_FLAG_MUTUAL) {
+
+ SILC_LOG_DEBUG(("We are doing mutual authentication"));
+
+ if (!recv_payload->pk_data && verify_key) {
+ SILC_LOG_DEBUG(("Remote end did not send its public key (or "
+ "certificate), even though we require it"));
+ ske->status = SILC_SKE_STATUS_PUBLIC_KEY_NOT_PROVIDED;
+ return status;
+ }
+
+ if (verify_key) {
+ SILC_LOG_DEBUG(("Verifying public key"));
+
+ (*verify_key)(ske, recv_payload->pk_data, recv_payload->pk_len,
+ recv_payload->pk_type, verify_context,
+ silc_ske_responder_phase2_final, finish);
+
+ /* We will continue to the final state after the public key has
+ been verified by the caller. */
+ return SILC_SKE_STATUS_PENDING;
+ }
+ }
+
+ /* Continue to final state */
+ silc_ske_responder_phase2_final(ske, SILC_SKE_STATUS_OK, finish);
+
+ return SILC_SKE_STATUS_OK;
}
/* This functions generates the secret key KEY = e ^ x mod p, and, a hash
projects / silc.git / blobdiff