payload->cookie_len = SILC_SKE_COOKIE_LEN;
memcpy(payload->cookie, rp->cookie, SILC_SKE_COOKIE_LEN);
+ /* In case IV included flag and session port is set the first 16-bits of
+ cookie will include our session port. */
+ if (rp->flags & SILC_SKE_SP_FLAG_IV_INCLUDED && ske->session_port)
+ SILC_PUT16_MSB(ske->session_port, payload->cookie);
+
/* Put our version to our reply */
payload->version = strdup(ske->version);
if (!payload->version) {
return status;
}
+/* Assembles security properties */
+
+static SilcSKEStartPayload
+silc_ske_assemble_security_properties(SilcSKE ske,
+ SilcSKESecurityPropertyFlag flags,
+ const char *version)
+{
+ SilcSKEStartPayload rp;
+ int i;
+
+ SILC_LOG_DEBUG(("Assembling KE Start Payload"));
+
+ rp = silc_calloc(1, sizeof(*rp));
+
+ /* Set flags */
+ rp->flags = (unsigned char)flags;
+
+ /* Set random cookie */
+ rp->cookie = silc_calloc(SILC_SKE_COOKIE_LEN, sizeof(*rp->cookie));
+ for (i = 0; i < SILC_SKE_COOKIE_LEN; i++)
+ rp->cookie[i] = silc_rng_get_byte_fast(ske->rng);
+ rp->cookie_len = SILC_SKE_COOKIE_LEN;
+
+ /* In case IV included flag and session port is set the first 16-bits of
+ cookie will include our session port. */
+ if (flags & SILC_SKE_SP_FLAG_IV_INCLUDED && ske->session_port)
+ SILC_PUT16_MSB(ske->session_port, rp->cookie);
+
+ /* Put version */
+ rp->version = strdup(version);
+ rp->version_len = strlen(version);
+
+ /* Get supported Key Exhange groups */
+ rp->ke_grp_list = silc_ske_get_supported_groups();
+ rp->ke_grp_len = strlen(rp->ke_grp_list);
+
+ /* Get supported PKCS algorithms */
+ rp->pkcs_alg_list = silc_pkcs_get_supported();
+ rp->pkcs_alg_len = strlen(rp->pkcs_alg_list);
+
+ /* Get supported encryption algorithms */
+ rp->enc_alg_list = silc_cipher_get_supported();
+ rp->enc_alg_len = strlen(rp->enc_alg_list);
+
+ /* Get supported hash algorithms */
+ rp->hash_alg_list = silc_hash_get_supported();
+ rp->hash_alg_len = strlen(rp->hash_alg_list);
+
+ /* Get supported HMACs */
+ rp->hmac_alg_list = silc_hmac_get_supported();
+ rp->hmac_alg_len = strlen(rp->hmac_alg_list);
+
+ /* XXX */
+ /* Get supported compression algorithms */
+ rp->comp_alg_list = strdup("none");
+ rp->comp_alg_len = strlen("none");
+
+ rp->len = 1 + 1 + 2 + SILC_SKE_COOKIE_LEN +
+ 2 + rp->version_len +
+ 2 + rp->ke_grp_len + 2 + rp->pkcs_alg_len +
+ 2 + rp->enc_alg_len + 2 + rp->hash_alg_len +
+ 2 + rp->hmac_alg_len + 2 + rp->comp_alg_len;
+
+ return rp;
+}
+
/******************************* Protocol API *******************************/
SilcSKESecurityProperties prop;
SilcSKEDiffieHellmanGroup group;
SilcBuffer packet_buf = &ske->packet->buffer;
+ int coff = 0;
SILC_LOG_DEBUG(("Start"));
return SILC_FSM_CONTINUE;
}
- /* Check that the cookie is returned unmodified */
- if (memcmp(ske->start_payload->cookie, payload->cookie,
- ske->start_payload->cookie_len)) {
+ /* Check that the cookie is returned unmodified. In case IV included
+ flag and session port has been set, the first two bytes of cookie
+ are the session port and we ignore them in this check. */
+ if (payload->flags & SILC_SKE_SP_FLAG_IV_INCLUDED && ske->session_port)
+ coff = 2;
+ if (memcmp(ske->start_payload->cookie + coff, payload->cookie + coff,
+ SILC_SKE_COOKIE_LEN - coff)) {
/** Invalid cookie */
- SILC_LOG_ERROR(("Responder modified our cookie and it must not do it"));
+ SILC_LOG_ERROR(("Invalid cookie, modified or unsupported feature"));
ske->status = SILC_SKE_STATUS_INVALID_COOKIE;
silc_fsm_next(fsm, silc_ske_st_initiator_error);
return SILC_FSM_CONTINUE;
SilcAsyncOperation
silc_ske_initiator(SilcSKE ske,
SilcPacketStream stream,
+ SilcSKEParams params,
SilcSKEStartPayload start_payload)
{
SILC_LOG_DEBUG(("Start SKE as initiator"));
- if (!ske || !stream || !start_payload)
+ if (!ske || !stream || !params || !params->version)
return NULL;
if (!silc_async_init(&ske->op, silc_ske_abort, NULL, ske))
ske->schedule))
return NULL;
+ if (params->flags & SILC_SKE_SP_FLAG_IV_INCLUDED)
+ ske->session_port = params->session_port;
+
+ /* Generate security properties if not provided */
+ if (!start_payload) {
+ start_payload = silc_ske_assemble_security_properties(ske,
+ params->flags,
+ params->version);
+ if (!start_payload)
+ return NULL;
+ }
+
ske->start_payload = start_payload;
/* Link to packet stream to get key exchange packets */
SilcAsyncOperation
silc_ske_responder(SilcSKE ske,
SilcPacketStream stream,
- const char *version,
- SilcSKESecurityPropertyFlag flags)
+ SilcSKEParams params)
{
SILC_LOG_DEBUG(("Start SKE as responder"));
- if (!ske || !stream || !version) {
+ if (!ske || !stream || !params || !params->version) {
return NULL;
}
ske->schedule))
return NULL;
- ske->flags = flags;
- ske->version = strdup(version);
+ ske->responder = TRUE;
+ ske->flags = params->flags;
+ if (ske->flags & SILC_SKE_SP_FLAG_IV_INCLUDED)
+ ske->session_port = params->session_port;
+ ske->version = strdup(params->version);
if (!ske->version)
return NULL;
- ske->responder = TRUE;
/* Link to packet stream to get key exchange packets */
ske->stream = stream;
return &ske->op;
}
-/* Assembles security properties */
-
-SilcSKEStartPayload
-silc_ske_assemble_security_properties(SilcSKE ske,
- SilcSKESecurityPropertyFlag flags,
- const char *version)
-{
- SilcSKEStartPayload rp;
- int i;
-
- SILC_LOG_DEBUG(("Assembling KE Start Payload"));
-
- rp = silc_calloc(1, sizeof(*rp));
-
- /* Set flags */
- rp->flags = (unsigned char)flags;
-
- /* Set random cookie */
- rp->cookie = silc_calloc(SILC_SKE_COOKIE_LEN, sizeof(*rp->cookie));
- for (i = 0; i < SILC_SKE_COOKIE_LEN; i++)
- rp->cookie[i] = silc_rng_get_byte_fast(ske->rng);
- rp->cookie_len = SILC_SKE_COOKIE_LEN;
-
- /* Put version */
- rp->version = strdup(version);
- rp->version_len = strlen(version);
-
- /* Get supported Key Exhange groups */
- rp->ke_grp_list = silc_ske_get_supported_groups();
- rp->ke_grp_len = strlen(rp->ke_grp_list);
-
- /* Get supported PKCS algorithms */
- rp->pkcs_alg_list = silc_pkcs_get_supported();
- rp->pkcs_alg_len = strlen(rp->pkcs_alg_list);
-
- /* Get supported encryption algorithms */
- rp->enc_alg_list = silc_cipher_get_supported();
- rp->enc_alg_len = strlen(rp->enc_alg_list);
-
- /* Get supported hash algorithms */
- rp->hash_alg_list = silc_hash_get_supported();
- rp->hash_alg_len = strlen(rp->hash_alg_list);
-
- /* Get supported HMACs */
- rp->hmac_alg_list = silc_hmac_get_supported();
- rp->hmac_alg_len = strlen(rp->hmac_alg_list);
-
- /* XXX */
- /* Get supported compression algorithms */
- rp->comp_alg_list = strdup("none");
- rp->comp_alg_len = strlen("none");
-
- rp->len = 1 + 1 + 2 + SILC_SKE_COOKIE_LEN +
- 2 + rp->version_len +
- 2 + rp->ke_grp_len + 2 + rp->pkcs_alg_len +
- 2 + rp->enc_alg_len + 2 + rp->hash_alg_len +
- 2 + rp->hmac_alg_len + 2 + rp->comp_alg_len;
-
- return rp;
-}
-
/* Processes the provided key material `data' as the SILC protocol
specification defines. */
} *SilcSKERekeyMaterial;
/***/
+/****s* silcske/SilcSKEAPI/SilcSKEParams
+ *
+ * NAME
+ *
+ * typedef struct { ... } *SilcSKEParams, SilcSKEParamsStruct;
+ *
+ * DESCRIPTION
+ *
+ * SKE parameters structure. This structure is given as argument to
+ * silc_ske_initiator and silc_ske_responder functions.
+ *
+ * SOURCE
+ */
+typedef struct {
+ /* The SKE version string that is sent to the remote end. This field
+ must be set. Caller must free the pointer. */
+ char *version;
+
+ /* Security property flags. When initiator sets these it requests them
+ from the responder. Responder may set here the flags it supports
+ and wants to enforce for the initiator. */
+ SilcSKESecurityPropertyFlag flags;
+
+ /* SILC Session port when using UDP/IP and SILC_SKE_SP_FLAG_IV_INCLUDED
+ flag. It is the port the remote will use as SILC session port after
+ the key exchange protocol. Ignored without SILC_SKE_SP_FLAG_IV_INCLUDED
+ flag. */
+ SilcUInt16 session_port;
+} *SilcSKEParams, SilcSKEParamsStruct;
+/***/
+
/****d* silcske/SilcSKEAPI/SilcSKEPKType
*
* NAME
* EXMPALE
*
* // Initiator example
+ * params.version = version;
+ * params.flags = SILC_SKE_SP_FLAG_PFS | SILC_SKE_SP_FLAG_MUTUAL;
* ske = silc_ske_alloc(rng, scheduler, NULL, pk, prv, app);
* silc_ske_set_callbacks(ske, verify_public_key, completion, app);
- * start_payload =
- * silc_ske_assemble_security_properties(ske, SILC_SKE_SP_FLAG_PFS |
- * SILC_SKE_SP_FLAG_MUTUAL,
- * version);
- * silc_ske_initiator_start(ske, stream, start_payload);
+ * silc_ske_initiator_start(ske, stream, ¶ms, NULL);
*
***/
SilcSKE silc_ske_alloc(SilcRng rng, SilcSchedule schedule,
* SilcAsyncOperation
* silc_ske_initiator_start(SilcSKE ske,
* SilcPacketStream stream,
+ * SilcSKEParams params,
* SilcSKEStartPayload start_payload);
*
* DESCRIPTION
* callback that was set in silc_ske_set_callbacks will be called once
* the protocol has completed. The `stream' is the network connection
* to the remote host. The SKE library will handle all key exchange
- * packets sent and received in the `stream' connection.
+ * packets sent and received in the `stream' connection. The `params'
+ * include SKE parameters, and it must be provided.
*
- * The `start_payload' includes all configured security properties that
- * will be sent to the responder. The `start_payload' must be provided.
- * It can be created by calling silc_ske_assemble_security_properties
- * function. The caller must not free the payload once it has been
- * given as argument to this function.
+ * If the `start_payload' is NULL the library will generate it
+ * automatically. Caller may provide it if it wants to send its own
+ * security properties instead of using the default ones library
+ * generates. If caller provides it, it must not free it once it has
+ * been given as argument to this function.
*
* This function returns SilcAsyncOperation operation context which can
* be used to control the protocol from the application. Application may
SilcAsyncOperation
silc_ske_initiator(SilcSKE ske,
SilcPacketStream stream,
+ SilcSKEParams params,
SilcSKEStartPayload start_payload);
/****f* silcske/SilcSKEAPI/silc_ske_responder_start
* SilcAsyncOperation
* silc_ske_responder_start(SilcSKE ske,
* SilcPacketStream stream,
- * const char *version,
- * SilcBuffer start_payload,
- * SilcSKESecurityPropertyFlag flags);
+ * SilcSKEParams params);
*
* DESCRIPTION
*
* callback that was set in silc_ske_set_callbacks will be called once
* the protocol has completed. The `stream' is the network connection
* to the remote host. The SKE library will handle all key exchange
- * packets sent and received in the `stream' connection.
- *
- * The `version' is the responder's SILC protocol version that will be
- * sent in reply to the initiator. The `flags' indicates the
- * SilcSKESecurityPropertyFlag flags that responder supports and enforces
- * for the initiator. Responder may, for example, enforce that the PFS
- * will be performed in rekey.
+ * packets sent and received in the `stream' connection. The `params'
+ * include SKE parameters, and must be provided.
*
* This function returns SilcAsyncOperation operation context which can
* be used to control the protocol from the application. Application may
SilcAsyncOperation
silc_ske_responder(SilcSKE ske,
SilcPacketStream stream,
- const char *version,
- SilcSKESecurityPropertyFlag flags);
+ SilcSKEParams params);
SilcAsyncOperation
silc_ske_rekey_initiator(SilcSKE ske,
SilcBuffer ke_payload,
SilcSKERekeyMaterial rekey);
-/****f* silcske/SilcSKEAPI/silc_ske_assemble_security_properties
- *
- * SYNOPSIS
- *
- * SilcSKEStartPayload
- * silc_ske_assemble_security_properties(SilcSKE ske,
- * SilcSKESecurityPropertyFlag flags,
- * const char *version);
- *
- * DESCRIPTION
- *
- * Assembles security properties to Key Exchange Start Payload to be
- * sent to the remote end. This checks system wide (SILC system, that is)
- * settings and chooses from those. However, if other properties
- * should be used this function is easy to replace by another function.
- * Returns NULL on error. This is an utility function. This is used
- * by the initiator of the protocol. The `version' is the local SILC
- * protocol version string.
- *
- ***/
-SilcSKEStartPayload
-silc_ske_assemble_security_properties(SilcSKE ske,
- SilcSKESecurityPropertyFlag flags,
- const char *version);
-
/****f* silcske/SilcSKEAPI/silc_ske_assemble_security_properties
*
* SYNOPSIS
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