silcske.c
- Author: Pekka Riikonen <priikone@poseidon.pspt.fi>
+ Author: Pekka Riikonen <priikone@silcnet.org>
- Copyright (C) 2000 - 2001 Pekka Riikonen
+ Copyright (C) 2000 - 2005 Pekka Riikonen
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
- (at your option) any later version.
-
+ the Free Software Foundation; version 2 of the License.
+
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
/* $Id$ */
#include "silcincludes.h"
-#include "payload_internal.h"
+#include "silcske.h"
#include "groups_internal.h"
+/* Static functions */
+static SilcSKEStatus silc_ske_create_rnd(SilcSKE ske, SilcMPInt *n,
+ SilcUInt32 len,
+ SilcMPInt *rnd);
+static SilcSKEStatus silc_ske_make_hash(SilcSKE ske,
+ unsigned char *return_hash,
+ SilcUInt32 *return_hash_len,
+ int initiator);
+
+/* Structure to hold all SKE callbacks. */
+struct SilcSKECallbacksStruct {
+ SilcSKESendPacketCb send_packet;
+ SilcSKECb payload_receive;
+ SilcSKEVerifyCb verify_key;
+ SilcSKECb proto_continue;
+ SilcSKECheckVersion check_version;
+ void *context;
+};
+
/* Allocates new SKE object. */
-SilcSKE silc_ske_alloc()
+SilcSKE silc_ske_alloc(SilcRng rng, void *context)
{
SilcSKE ske;
SILC_LOG_DEBUG(("Allocating new Key Exchange object"));
ske = silc_calloc(1, sizeof(*ske));
+ if (!ske)
+ return NULL;
ske->status = SILC_SKE_STATUS_OK;
+ ske->rng = rng;
+ ske->user_data = context;
+ ske->users = 1;
return ske;
}
void silc_ske_free(SilcSKE ske)
{
+ ske->users--;
+ if (ske->users > 0) {
+ SILC_LOG_DEBUG(("Key Exchange set to FREED status"));
+ ske->status = SILC_SKE_STATUS_FREED;
+ return;
+ }
+
SILC_LOG_DEBUG(("Freeing Key Exchange object"));
if (ske) {
/* Free KE payload */
if (ske->ke1_payload)
silc_ske_payload_ke_free(ske->ke1_payload);
+ if (ske->ke2_payload)
+ silc_ske_payload_ke_free(ske->ke2_payload);
+ silc_free(ske->remote_version);
/* Free rest */
if (ske->prop) {
if (ske->prop->group)
- silc_free(ske->prop->group);
+ silc_ske_group_free(ske->prop->group);
if (ske->prop->pkcs)
silc_pkcs_free(ske->prop->pkcs);
if (ske->prop->cipher)
}
if (ske->start_payload_copy)
silc_buffer_free(ske->start_payload_copy);
- if (ske->pk)
- silc_free(ske->pk);
if (ske->x) {
- silc_mp_clear(ske->x);
+ silc_mp_uninit(ske->x);
silc_free(ske->x);
}
if (ske->KEY) {
- silc_mp_clear(ske->KEY);
+ silc_mp_uninit(ske->KEY);
silc_free(ske->KEY);
}
- if (ske->hash)
- silc_free(ske->hash);
+ silc_free(ske->hash);
+ silc_free(ske->callbacks);
+
+ memset(ske, 'F', sizeof(*ske));
silc_free(ske);
}
}
+/* Sets the callback functions for the SKE session.
+
+ The `send_packet' callback is a function that sends the packet to
+ network. The SKE library will call it at any time packet needs to
+ be sent to the remote host.
+
+ The `payload_receive' callback is called when the remote host's Key
+ Exchange Start Payload has been processed. The payload is saved
+ to ske->start_payload if the application would need it. The application
+ must also provide the payload to the next state of the SKE.
+
+ The `verify_key' callback is called to verify the received public key
+ or certificate. The verification process is most likely asynchronous.
+ That is why the application must call the completion callback when the
+ verification process has been completed. The library then calls the user
+ callback (`proto_continue'), if it is provided to indicate that the SKE
+ protocol may continue.
+
+ The `proto_continue' callback is called to indicate that it is
+ safe to continue the execution of the SKE protocol after executing
+ an asynchronous operation, such as calling the `verify_key' callback
+ function, which is asynchronous. The application should check the
+ ske->status in this function to check whether it is Ok to continue
+ the execution of the protocol.
+
+ The `check_version' callback is called to verify the remote host's
+ version. The application may check its own version against the remote
+ host's version and determine whether supporting the remote host
+ is possible.
+
+ The `context' is passed as argument to all of the above callback
+ functions. */
+
+void silc_ske_set_callbacks(SilcSKE ske,
+ SilcSKESendPacketCb send_packet,
+ SilcSKECb payload_receive,
+ SilcSKEVerifyCb verify_key,
+ SilcSKECb proto_continue,
+ SilcSKECheckVersion check_version,
+ void *context)
+{
+ if (ske->callbacks)
+ silc_free(ske->callbacks);
+ ske->callbacks = silc_calloc(1, sizeof(*ske->callbacks));
+ if (!ske->callbacks)
+ return;
+ ske->callbacks->send_packet = send_packet;
+ ske->callbacks->payload_receive = payload_receive;
+ ske->callbacks->verify_key = verify_key;
+ ske->callbacks->proto_continue = proto_continue;
+ ske->callbacks->check_version = check_version;
+ ske->callbacks->context = context;
+}
+
/* Starts the SILC Key Exchange protocol for initiator. The connection
to the remote end must be established before calling this function
and the connecting socket must be sent as argument. This function
- creates the Key Exchange Start Paload which includes all our
+ creates the Key Exchange Start Payload which includes all our
configured security properties. This payload is then sent to the
remote end for further processing. This payload must be sent as
argument to the function, however, it must not be encoded
- already, it is done by this function.
+ already, it is done by this function. The caller must not free
+ the `start_payload' since the SKE library will save it.
The packet sending is done by calling a callback function. Caller
must provide a routine to send the packet. */
SilcSKEStatus silc_ske_initiator_start(SilcSKE ske, SilcRng rng,
SilcSocketConnection sock,
- SilcSKEStartPayload *start_payload,
- SilcSKESendPacketCb send_packet,
- void *context)
+ SilcSKEStartPayload *start_payload)
{
SilcSKEStatus status = SILC_SKE_STATUS_OK;
SilcBuffer payload_buf;
if (status != SILC_SKE_STATUS_OK)
return status;
- /* Take a copy of the payload buffer for future use. It is used to
- compute the HASH value. */
- ske->start_payload_copy = silc_buffer_copy(payload_buf);
-
/* Send the packet. */
- if (send_packet)
- (*send_packet)(ske, payload_buf, SILC_PACKET_KEY_EXCHANGE, context);
+ if (ske->callbacks->send_packet)
+ (*ske->callbacks->send_packet)(ske, payload_buf, SILC_PACKET_KEY_EXCHANGE,
+ ske->callbacks->context);
- silc_buffer_free(payload_buf);
+ /* Save the the payload buffer for future use. It is later used to
+ compute the HASH value. */
+ ske->start_payload_copy = payload_buf;
+ ske->start_payload = start_payload;
return status;
}
security properties selected by the responder from our payload
sent in the silc_ske_initiator_start function. */
-SilcSKEStatus silc_ske_initiator_phase_1(SilcSKE ske,
- SilcBuffer start_payload,
- SilcSKECb callback,
- void *context)
+SilcSKEStatus silc_ske_initiator_phase_1(SilcSKE ske,
+ SilcBuffer start_payload)
{
SilcSKEStatus status = SILC_SKE_STATUS_OK;
SilcSKEStartPayload *payload;
status = silc_ske_payload_start_decode(ske, start_payload, &payload);
if (status != SILC_SKE_STATUS_OK) {
ske->status = status;
+ silc_ske_payload_start_free(ske->start_payload);
return status;
}
+ /* Check that the cookie is returned unmodified */
+ if (memcmp(ske->start_payload->cookie, payload->cookie,
+ ske->start_payload->cookie_len)) {
+ SILC_LOG_ERROR(("Responder modified our cookie and it must not do it"));
+ ske->status = SILC_SKE_STATUS_INVALID_COOKIE;
+ silc_ske_payload_start_free(ske->start_payload);
+ return status;
+ }
+
+ /* Check version string */
+ if (ske->callbacks->check_version) {
+ status = ske->callbacks->check_version(ske, payload->version,
+ payload->version_len,
+ ske->callbacks->context);
+ if (status != SILC_SKE_STATUS_OK) {
+ ske->status = status;
+ silc_ske_payload_start_free(ske->start_payload);
+ return status;
+ }
+ }
+
+ /* Free our KE Start Payload context, we don't need it anymore. */
+ silc_ske_payload_start_free(ske->start_payload);
+
/* Take the selected security properties into use while doing
- the key exchange. This is used only while doing the key
+ the key exchange. This is used only while doing the key
exchange. The same data is returned to upper levels by calling
the callback function. */
ske->prop = prop = silc_calloc(1, sizeof(*prop));
+ if (!ske->prop)
+ goto err;
prop->flags = payload->flags;
- status = silc_ske_get_group_by_name(payload->ke_grp_list, &group);
+ status = silc_ske_group_get_by_name(payload->ke_grp_list, &group);
if (status != SILC_SKE_STATUS_OK)
goto err;
goto err;
}
+ /* Save remote's KE Start Payload */
ske->start_payload = payload;
/* Return the received payload by calling the callback function. */
- if (callback)
- (*callback)(ske, context);
+ if (ske->callbacks->payload_receive)
+ (*ske->callbacks->payload_receive)(ske, ske->callbacks->context);
return status;
if (payload)
silc_ske_payload_start_free(payload);
- silc_free(group);
+ silc_ske_group_free(group);
if (prop->pkcs)
silc_pkcs_free(prop->pkcs);
return status;
}
-/* This function creates random number x, such that 1 < x < q and
- computes e = g ^ x mod p and sends the result to the remote end in
+/* This function creates random number x, such that 1 < x < q and
+ computes e = g ^ x mod p and sends the result to the remote end in
Key Exchange Payload. */
SilcSKEStatus silc_ske_initiator_phase_2(SilcSKE ske,
SilcPublicKey public_key,
SilcPrivateKey private_key,
- SilcSKESendPacketCb send_packet,
- void *context)
+ SilcSKEPKType pk_type)
{
SilcSKEStatus status = SILC_SKE_STATUS_OK;
SilcBuffer payload_buf;
- SilcInt *x, e;
+ SilcMPInt *x;
SilcSKEKEPayload *payload;
- uint32 pk_len;
+ SilcUInt32 pk_len;
SILC_LOG_DEBUG(("Start"));
/* Create the random number x, 1 < x < q. */
x = silc_calloc(1, sizeof(*x));
+ if (!x){
+ ske->status = SILC_SKE_STATUS_OUT_OF_MEMORY;
+ return ske->status;
+ }
silc_mp_init(x);
- status =
- silc_ske_create_rnd(ske, ske->prop->group->group_order,
+ status =
+ silc_ske_create_rnd(ske, &ske->prop->group->group_order,
silc_mp_sizeinbase(&ske->prop->group->group_order, 2),
x);
if (status != SILC_SKE_STATUS_OK) {
- silc_mp_clear(x);
+ silc_mp_uninit(x);
silc_free(x);
ske->status = status;
return status;
}
- SILC_LOG_DEBUG(("Computing e = g ^ x mod p"));
-
- /* Do the Diffie Hellman computation, e = g ^ x mod p */
- silc_mp_init(&e);
- silc_mp_powm(&e, &ske->prop->group->generator, x,
- &ske->prop->group->group);
-
/* Encode the result to Key Exchange Payload. */
payload = silc_calloc(1, sizeof(*payload));
+ if (!payload) {
+ silc_mp_uninit(x);
+ silc_free(x);
+ ske->status = SILC_SKE_STATUS_OUT_OF_MEMORY;
+ return ske->status;
+ }
ske->ke1_payload = payload;
- payload->x = e;
+ SILC_LOG_DEBUG(("Computing e = g ^ x mod p"));
+
+ /* Do the Diffie Hellman computation, e = g ^ x mod p */
+ silc_mp_init(&payload->x);
+ silc_mp_pow_mod(&payload->x, &ske->prop->group->generator, x,
+ &ske->prop->group->group);
/* Get public key */
if (public_key) {
payload->pk_data = silc_pkcs_public_key_encode(public_key, &pk_len);
if (!payload->pk_data) {
- silc_mp_clear(x);
+ silc_mp_uninit(x);
silc_free(x);
- silc_mp_clear(&e);
+ silc_mp_uninit(&payload->x);
silc_free(payload);
+ ske->ke1_payload = NULL;
ske->status = SILC_SKE_STATUS_OK;
return ske->status;
}
payload->pk_len = pk_len;
}
- payload->pk_type = SILC_SKE_PK_TYPE_SILC;
+ payload->pk_type = pk_type;
/* Compute signature data if we are doing mutual authentication */
if (private_key && ske->start_payload->flags & SILC_SKE_SP_FLAG_MUTUAL) {
- unsigned char hash[32], sign[1024];
- uint32 hash_len, sign_len;
+ unsigned char hash[SILC_HASH_MAXLEN], sign[2048 + 1];
+ SilcUInt32 hash_len, sign_len;
SILC_LOG_DEBUG(("We are doing mutual authentication"));
SILC_LOG_DEBUG(("Computing HASH_i value"));
silc_ske_make_hash(ske, hash, &hash_len, TRUE);
SILC_LOG_DEBUG(("Signing HASH_i value"));
-
+
/* Sign the hash value */
- silc_pkcs_private_key_data_set(ske->prop->pkcs, private_key->prv,
+ silc_pkcs_private_key_data_set(ske->prop->pkcs, private_key->prv,
private_key->prv_len);
- silc_pkcs_sign(ske->prop->pkcs, hash, hash_len, sign, &sign_len);
- payload->sign_data = silc_calloc(sign_len, sizeof(unsigned char));
- memcpy(payload->sign_data, sign, sign_len);
- memset(sign, 0, sizeof(sign));
+ if (silc_pkcs_get_key_len(ske->prop->pkcs) / 8 > sizeof(sign) - 1 ||
+ !silc_pkcs_sign(ske->prop->pkcs, hash, hash_len, sign, &sign_len)) {
+ silc_mp_uninit(x);
+ silc_free(x);
+ silc_mp_uninit(&payload->x);
+ silc_free(payload->pk_data);
+ silc_free(payload);
+ ske->ke1_payload = NULL;
+ ske->status = SILC_SKE_STATUS_SIGNATURE_ERROR;
+ return ske->status;
+ }
+ payload->sign_data = silc_memdup(sign, sign_len);
payload->sign_len = sign_len;
+ memset(sign, 0, sizeof(sign));
}
status = silc_ske_payload_ke_encode(ske, payload, &payload_buf);
if (status != SILC_SKE_STATUS_OK) {
- silc_mp_clear(x);
+ silc_mp_uninit(x);
silc_free(x);
- silc_mp_clear(&e);
+ silc_mp_uninit(&payload->x);
silc_free(payload->pk_data);
+ silc_free(payload->sign_data);
silc_free(payload);
+ ske->ke1_payload = NULL;
ske->status = status;
return status;
}
ske->x = x;
/* Send the packet. */
- if (send_packet)
- (*send_packet)(ske, payload_buf, SILC_PACKET_KEY_EXCHANGE_1, context);
+ if (ske->callbacks->send_packet)
+ (*ske->callbacks->send_packet)(ske, payload_buf,
+ SILC_PACKET_KEY_EXCHANGE_1,
+ ske->callbacks->context);
silc_buffer_free(payload_buf);
/* An initiator finish final callback that is called to indicate that
the SKE protocol may continue. */
-typedef struct {
- SilcSKECb callback;
- void *context;
-} *SKEInitiatorFinish;
-
static void silc_ske_initiator_finish_final(SilcSKE ske,
SilcSKEStatus status,
void *context)
{
- SKEInitiatorFinish finish = (SKEInitiatorFinish)context;
- SilcSKEKEPayload *payload = ske->ke2_payload;
- unsigned char hash[32];
- uint32 hash_len;
+ SilcSKEKEPayload *payload;
+ unsigned char hash[SILC_HASH_MAXLEN];
+ SilcUInt32 hash_len;
SilcPublicKey public_key = NULL;
+ /* If the SKE was freed during the async call then free it really now,
+ otherwise just decrement the reference counter. */
+ if (ske->status == SILC_SKE_STATUS_FREED) {
+ silc_ske_free(ske);
+ return;
+ }
+
/* 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;
+ ske->users--;
+ payload = ske->ke2_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;
- if (finish->callback)
- finish->callback(ske, finish->context);
- silc_free(finish);
+ if (ske->callbacks->proto_continue)
+ ske->callbacks->proto_continue(ske, ske->callbacks->context);
return;
}
- /* 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 (payload->pk_data) {
+ /* 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;
+ SILC_LOG_ERROR(("Unsupported/malformed public key received"));
+ if (ske->callbacks->proto_continue)
+ ske->callbacks->proto_continue(ske, ske->callbacks->context);
+ return;
+ }
- SILC_LOG_DEBUG(("Public key is authentic"));
+ SILC_LOG_DEBUG(("Public key is authentic"));
- if (payload->pk_data) {
/* Compute the hash value */
status = silc_ske_make_hash(ske, hash, &hash_len, FALSE);
if (status != SILC_SKE_STATUS_OK)
goto err;
- ske->hash = silc_calloc(hash_len, sizeof(unsigned char));
- memcpy(ske->hash, hash, hash_len);
+ ske->hash = silc_memdup(hash, hash_len);
ske->hash_len = hash_len;
SILC_LOG_DEBUG(("Verifying signature (HASH)"));
/* Verify signature */
- silc_pkcs_public_key_data_set(ske->prop->pkcs, public_key->pk,
- public_key->pk_len);
- if (silc_pkcs_verify(ske->prop->pkcs, payload->sign_data,
+ silc_pkcs_public_key_set(ske->prop->pkcs, public_key);
+ if (silc_pkcs_verify(ske->prop->pkcs, payload->sign_data,
payload->sign_len, hash, hash_len) == FALSE) {
-
- SILC_LOG_DEBUG(("Signature don't match"));
-
+ SILC_LOG_ERROR(("Signature verification failed, incorrect signature"));
status = SILC_SKE_STATUS_INCORRECT_SIGNATURE;
goto err;
}
SILC_LOG_DEBUG(("Signature is Ok"));
-
+
silc_pkcs_public_key_free(public_key);
memset(hash, 'F', hash_len);
}
ske->status = SILC_SKE_STATUS_OK;
/* Call the callback. The caller may now continue the SKE protocol. */
- if (finish->callback)
- finish->callback(ske, finish->context);
+ if (ske->callbacks->proto_continue)
+ ske->callbacks->proto_continue(ske, ske->callbacks->context);
- silc_free(finish);
return;
err:
silc_ske_payload_ke_free(payload);
ske->ke2_payload = NULL;
- silc_mp_clear(ske->KEY);
+ silc_mp_uninit(ske->KEY);
silc_free(ske->KEY);
ske->KEY = NULL;
ske->status = status;
/* Call the callback. */
- if (finish->callback)
- finish->callback(ske, finish->context);
- silc_free(finish);
+ if (ske->callbacks->proto_continue)
+ ske->callbacks->proto_continue(ske, ske->callbacks->context);
}
/* 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.
+ computes the secret shared key and verifies the signature.
- The `callback' will be called to indicate that the caller may
+ The `proto_continue' 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
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
+ 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)
+ SilcBuffer ke_payload)
{
SilcSKEStatus status = SILC_SKE_STATUS_OK;
SilcSKEKEPayload *payload;
- SilcInt *KEY;
- SKEInitiatorFinish finish;
+ SilcMPInt *KEY;
SILC_LOG_DEBUG(("Start"));
}
ske->ke2_payload = payload;
- if (!payload->pk_data && verify_key) {
+ if (!payload->pk_data && ske->callbacks->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;
/* 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);
+ silc_mp_pow_mod(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) {
+ if (payload->pk_data && ske->callbacks->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);
+
+ ske->users++;
+ (*ske->callbacks->verify_key)(ske, payload->pk_data, payload->pk_len,
+ payload->pk_type, ske->callbacks->context,
+ silc_ske_initiator_finish_final, NULL);
/* We will continue to the final state after the public key has
been verified by the caller. */
}
/* Continue to final state */
- silc_ske_initiator_finish_final(ske, SILC_SKE_STATUS_OK, finish);
+ ske->users++;
+ silc_ske_initiator_finish_final(ske, SILC_SKE_STATUS_OK, NULL);
return SILC_SKE_STATUS_OK;
silc_ske_payload_ke_free(payload);
ske->ke2_payload = NULL;
- silc_mp_clear(ske->KEY);
+ silc_mp_uninit(ske->KEY);
silc_free(ske->KEY);
ske->KEY = NULL;
/* Starts Key Exchange protocol for responder. Responder receives
Key Exchange Start Payload from initiator consisting of all the
security properties the initiator supports. This function decodes
- the payload and parses the payload further and selects the right
+ the payload and parses the payload further and selects the right
security properties. */
SilcSKEStatus silc_ske_responder_start(SilcSKE ske, SilcRng rng,
SilcSocketConnection sock,
- char *version,
+ const char *version,
SilcBuffer start_payload,
- int mutual_auth,
- SilcSKECb callback,
- void *context)
+ SilcSKESecurityPropertyFlag flags)
{
SilcSKEStatus status = SILC_SKE_STATUS_OK;
SilcSKEStartPayload *remote_payload = NULL, *payload = NULL;
ske->start_payload_copy = silc_buffer_copy(start_payload);
/* Force the mutual authentication flag if we want to do it. */
- if (mutual_auth) {
+ if (flags & SILC_SKE_SP_FLAG_MUTUAL) {
SILC_LOG_DEBUG(("Force mutual authentication"));
remote_payload->flags |= SILC_SKE_SP_FLAG_MUTUAL;
}
+ /* Force PFS flag if we require it */
+ if (flags & SILC_SKE_SP_FLAG_PFS) {
+ SILC_LOG_DEBUG(("Force PFS"));
+ remote_payload->flags |= SILC_SKE_SP_FLAG_PFS;
+ }
+
+ /* Disable IV Included flag if requested */
+ if (remote_payload->flags & SILC_SKE_SP_FLAG_IV_INCLUDED &&
+ !(flags & SILC_SKE_SP_FLAG_IV_INCLUDED)) {
+ SILC_LOG_DEBUG(("We do not support IV Included flag"));
+ remote_payload->flags &= ~SILC_SKE_SP_FLAG_IV_INCLUDED;
+ }
+
/* Parse and select the security properties from the payload */
payload = silc_calloc(1, sizeof(*payload));
status = silc_ske_select_security_properties(ske, version,
ske->start_payload = payload;
/* Call the callback function. */
- if (callback)
- (*callback)(ske, context);
+ if (ske->callbacks->payload_receive)
+ (*ske->callbacks->payload_receive)(ske, ske->callbacks->context);
+
+ silc_ske_payload_start_free(remote_payload);
return status;
err:
if (remote_payload)
silc_ske_payload_start_free(remote_payload);
- if (payload)
- silc_free(payload);
+ silc_free(payload);
if (status == SILC_SKE_STATUS_OK)
return SILC_SKE_STATUS_ERROR;
return status;
}
-/* The selected security properties from the initiator payload is now
+/* The selected security properties from the initiator payload is now
encoded into Key Exchange Start Payload and sent to the initiator. */
-SilcSKEStatus silc_ske_responder_phase_1(SilcSKE ske,
- SilcSKEStartPayload *start_payload,
- SilcSKESendPacketCb send_packet,
- void *context)
+SilcSKEStatus silc_ske_responder_phase_1(SilcSKE ske)
{
SilcSKEStatus status = SILC_SKE_STATUS_OK;
SilcBuffer payload_buf;
/* Allocate security properties from the payload. These are allocated
only for this negotiation and will be free'd after KE is over. */
ske->prop = prop = silc_calloc(1, sizeof(*prop));
- prop->flags = start_payload->flags;
- status = silc_ske_get_group_by_name(start_payload->ke_grp_list, &group);
+ prop->flags = ske->start_payload->flags;
+ status = silc_ske_group_get_by_name(ske->start_payload->ke_grp_list, &group);
if (status != SILC_SKE_STATUS_OK)
goto err;
prop->group = group;
- if (silc_pkcs_alloc(start_payload->pkcs_alg_list,
+ if (silc_pkcs_alloc(ske->start_payload->pkcs_alg_list,
&prop->pkcs) == FALSE) {
status = SILC_SKE_STATUS_UNKNOWN_PKCS;
goto err;
}
- if (silc_cipher_alloc(start_payload->enc_alg_list,
+ if (silc_cipher_alloc(ske->start_payload->enc_alg_list,
&prop->cipher) == FALSE) {
status = SILC_SKE_STATUS_UNKNOWN_CIPHER;
goto err;
}
- if (silc_hash_alloc(start_payload->hash_alg_list,
+ if (silc_hash_alloc(ske->start_payload->hash_alg_list,
&prop->hash) == FALSE) {
status = SILC_SKE_STATUS_UNKNOWN_HASH_FUNCTION;
goto err;
}
- if (silc_hmac_alloc(start_payload->hmac_alg_list, NULL,
+ if (silc_hmac_alloc(ske->start_payload->hmac_alg_list, NULL,
&prop->hmac) == FALSE) {
status = SILC_SKE_STATUS_UNKNOWN_HMAC;
goto err;
}
/* Encode the payload */
- status = silc_ske_payload_start_encode(ske, start_payload, &payload_buf);
+ status = silc_ske_payload_start_encode(ske, ske->start_payload,
+ &payload_buf);
if (status != SILC_SKE_STATUS_OK)
goto err;
/* Send the packet. */
- if (send_packet)
- (*send_packet)(ske, payload_buf, SILC_PACKET_KEY_EXCHANGE, context);
+ if (ske->callbacks->send_packet)
+ (*ske->callbacks->send_packet)(ske, payload_buf, SILC_PACKET_KEY_EXCHANGE,
+ ske->callbacks->context);
silc_buffer_free(payload_buf);
err:
if (group)
- silc_free(group);
+ silc_ske_group_free(group);
if (prop->pkcs)
silc_pkcs_free(prop->pkcs);
/* An responder phase 2 final callback that is called to indicate that
the SKE protocol may continue. */
-typedef struct {
- SilcSKECb callback;
- void *context;
-} *SKEResponderPhaseII;
-
static void silc_ske_responder_phase2_final(SilcSKE ske,
SilcSKEStatus status,
void *context)
{
- SKEResponderPhaseII finish = (SKEResponderPhaseII)context;
SilcSKEKEPayload *recv_payload, *send_payload;
- SilcInt *x, f;
+ SilcMPInt *x;
- recv_payload = ske->ke1_payload;
+ /* If the SKE was freed during the async call then free it really now,
+ otherwise just decrement the reference counter. */
+ if (ske->status == SILC_SKE_STATUS_FREED) {
+ silc_ske_free(ske);
+ return;
+ }
/* If the caller returns PENDING status SKE library will assume that
the caller will re-call this callback when it is not anymore in
if (status == SILC_SKE_STATUS_PENDING)
return;
+ ske->users--;
+ recv_payload = ske->ke1_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;
- if (finish->callback)
- finish->callback(ske, finish->context);
- silc_free(finish);
+ if (ske->callbacks->proto_continue)
+ ske->callbacks->proto_continue(ske, ske->callbacks->context);
return;
}
/* The public key verification was performed only if the Mutual
Authentication flag is set. */
- if (ske->start_payload &&
+ if (ske->start_payload &&
ske->start_payload->flags & SILC_SKE_SP_FLAG_MUTUAL) {
SilcPublicKey public_key = NULL;
- unsigned char hash[32];
- uint32 hash_len;
+ unsigned char hash[SILC_HASH_MAXLEN];
+ SilcUInt32 hash_len;
/* Decode the public key */
- if (!silc_pkcs_public_key_decode(recv_payload->pk_data,
- recv_payload->pk_len,
+ if (!silc_pkcs_public_key_decode(recv_payload->pk_data,
+ recv_payload->pk_len,
&public_key)) {
ske->status = SILC_SKE_STATUS_UNSUPPORTED_PUBLIC_KEY;
- if (finish->callback)
- finish->callback(ske, finish->context);
- silc_free(finish);
+ SILC_LOG_ERROR(("Unsupported/malformed public key received"));
+ if (ske->callbacks->proto_continue)
+ ske->callbacks->proto_continue(ske, ske->callbacks->context);
return;
}
status = silc_ske_make_hash(ske, hash, &hash_len, TRUE);
if (status != SILC_SKE_STATUS_OK) {
ske->status = status;
- if (finish->callback)
- finish->callback(ske, finish->context);
- silc_free(finish);
+ if (ske->callbacks->proto_continue)
+ ske->callbacks->proto_continue(ske, ske->callbacks->context);
return;
}
SILC_LOG_DEBUG(("Verifying signature (HASH_i)"));
-
+
/* Verify signature */
- silc_pkcs_public_key_data_set(ske->prop->pkcs, public_key->pk,
- public_key->pk_len);
- if (silc_pkcs_verify(ske->prop->pkcs, recv_payload->sign_data,
+ silc_pkcs_public_key_set(ske->prop->pkcs, public_key);
+ if (silc_pkcs_verify(ske->prop->pkcs, recv_payload->sign_data,
recv_payload->sign_len, hash, hash_len) == FALSE) {
-
- SILC_LOG_DEBUG(("Signature don't match"));
-
+ SILC_LOG_ERROR(("Signature verification failed, incorrect signature"));
ske->status = SILC_SKE_STATUS_INCORRECT_SIGNATURE;
- if (finish->callback)
- finish->callback(ske, finish->context);
- silc_free(finish);
+ if (ske->callbacks->proto_continue)
+ ske->callbacks->proto_continue(ske, ske->callbacks->context);
return;
}
-
+
SILC_LOG_DEBUG(("Signature is Ok"));
-
+
silc_pkcs_public_key_free(public_key);
memset(hash, 'F', hash_len);
}
/* Create the random number x, 1 < x < q. */
x = silc_calloc(1, sizeof(*x));
silc_mp_init(x);
- status =
- silc_ske_create_rnd(ske, ske->prop->group->group_order,
+ status =
+ silc_ske_create_rnd(ske, &ske->prop->group->group_order,
silc_mp_sizeinbase(&ske->prop->group->group_order, 2),
x);
if (status != SILC_SKE_STATUS_OK) {
- silc_mp_clear(x);
+ silc_mp_uninit(x);
silc_free(x);
ske->status = status;
- if (finish->callback)
- finish->callback(ske, finish->context);
- silc_free(finish);
+ if (ske->callbacks->proto_continue)
+ ske->callbacks->proto_continue(ske, ske->callbacks->context);
return;
}
- SILC_LOG_DEBUG(("Computing f = g ^ x mod p"));
-
- /* Do the Diffie Hellman computation, f = g ^ x mod p */
- silc_mp_init(&f);
- silc_mp_powm(&f, &ske->prop->group->generator, x,
- &ske->prop->group->group);
-
/* Save the results for later processing */
send_payload = silc_calloc(1, sizeof(*send_payload));
- send_payload->x = f;
ske->x = x;
ske->ke2_payload = send_payload;
+ SILC_LOG_DEBUG(("Computing f = g ^ x mod p"));
+
+ /* Do the Diffie Hellman computation, f = g ^ x mod p */
+ silc_mp_init(&send_payload->x);
+ silc_mp_pow_mod(&send_payload->x, &ske->prop->group->generator, x,
+ &ske->prop->group->group);
+
/* 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);
+ if (ske->callbacks->proto_continue)
+ ske->callbacks->proto_continue(ske, ske->callbacks->context);
}
/* This function receives the Key Exchange Payload from the initiator.
- This also performs the mutual authentication if required. Then, this
+ 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.
+ Exchange Payload.
- The `callback' will be called to indicate that the caller may
+ The `proto_continue' 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
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)
+ SilcBuffer ke_payload)
{
SilcSKEStatus status = SILC_SKE_STATUS_OK;
SilcSKEKEPayload *recv_payload;
- SKEResponderPhaseII finish;
SILC_LOG_DEBUG(("Start"));
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 &&
+ 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 "
+
+ if (!recv_payload->pk_data && ske->callbacks->verify_key) {
+ SILC_LOG_ERROR(("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) {
+ if (recv_payload->pk_data && ske->callbacks->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);
+ ske->users++;
+ (*ske->callbacks->verify_key)(ske, recv_payload->pk_data,
+ recv_payload->pk_len,
+ recv_payload->pk_type,
+ ske->callbacks->context,
+ silc_ske_responder_phase2_final, NULL);
/* We will continue to the final state after the public key has
been verified by the caller. */
}
/* Continue to final state */
- silc_ske_responder_phase2_final(ske, SILC_SKE_STATUS_OK, finish);
+ ske->users++;
+ silc_ske_responder_phase2_final(ske, SILC_SKE_STATUS_OK, NULL);
return SILC_SKE_STATUS_OK;
}
SilcSKEStatus silc_ske_responder_finish(SilcSKE ske,
SilcPublicKey public_key,
SilcPrivateKey private_key,
- SilcSKEPKType pk_type,
- SilcSKESendPacketCb send_packet,
- void *context)
+ SilcSKEPKType pk_type)
{
SilcSKEStatus status = SILC_SKE_STATUS_OK;
SilcBuffer payload_buf;
- SilcInt *KEY;
- unsigned char hash[32], sign[1024], *pk;
- uint32 hash_len, sign_len, pk_len;
+ SilcMPInt *KEY;
+ unsigned char hash[SILC_HASH_MAXLEN], sign[2048 + 1], *pk;
+ SilcUInt32 hash_len, sign_len, pk_len;
SILC_LOG_DEBUG(("Start"));
/* Compute the shared secret key */
KEY = silc_calloc(1, sizeof(*KEY));
silc_mp_init(KEY);
- silc_mp_powm(KEY, &ske->ke1_payload->x, ske->x,
- &ske->prop->group->group);
+ silc_mp_pow_mod(KEY, &ske->ke1_payload->x, ske->x,
+ &ske->prop->group->group);
ske->KEY = KEY;
if (public_key && private_key) {
SILC_LOG_DEBUG(("Getting public key"));
-
+
/* Get the public key */
pk = silc_pkcs_public_key_encode(public_key, &pk_len);
if (!pk) {
- status = SILC_SKE_STATUS_ERROR;
+ status = SILC_SKE_STATUS_OUT_OF_MEMORY;
goto err;
}
ske->ke2_payload->pk_data = pk;
ske->ke2_payload->pk_len = pk_len;
-
+
SILC_LOG_DEBUG(("Computing HASH value"));
-
+
/* Compute the hash value */
memset(hash, 0, sizeof(hash));
status = silc_ske_make_hash(ske, hash, &hash_len, FALSE);
if (status != SILC_SKE_STATUS_OK)
goto err;
- ske->hash = silc_calloc(hash_len, sizeof(unsigned char));
- memcpy(ske->hash, hash, hash_len);
+ ske->hash = silc_memdup(hash, hash_len);
ske->hash_len = hash_len;
-
+
SILC_LOG_DEBUG(("Signing HASH value"));
-
+
/* Sign the hash value */
- silc_pkcs_private_key_data_set(ske->prop->pkcs, private_key->prv,
+ silc_pkcs_private_key_data_set(ske->prop->pkcs, private_key->prv,
private_key->prv_len);
- silc_pkcs_sign(ske->prop->pkcs, hash, hash_len, sign, &sign_len);
- ske->ke2_payload->sign_data = silc_calloc(sign_len, sizeof(unsigned char));
- memcpy(ske->ke2_payload->sign_data, sign, sign_len);
- memset(sign, 0, sizeof(sign));
+ if (silc_pkcs_get_key_len(ske->prop->pkcs) / 8 > sizeof(sign) - 1 ||
+ !silc_pkcs_sign(ske->prop->pkcs, hash, hash_len, sign, &sign_len)) {
+ status = SILC_SKE_STATUS_SIGNATURE_ERROR;
+ goto err;
+ }
+ ske->ke2_payload->sign_data = silc_memdup(sign, sign_len);
ske->ke2_payload->sign_len = sign_len;
+ memset(sign, 0, sizeof(sign));
}
ske->ke2_payload->pk_type = pk_type;
goto err;
/* Send the packet. */
- if (send_packet)
- (*send_packet)(ske, payload_buf, SILC_PACKET_KEY_EXCHANGE_2, context);
+ if (ske->callbacks->send_packet)
+ (*ske->callbacks->send_packet)(ske, payload_buf,
+ SILC_PACKET_KEY_EXCHANGE_2,
+ ske->callbacks->context);
silc_buffer_free(payload_buf);
return status;
err:
- silc_mp_clear(ske->KEY);
+ silc_mp_uninit(ske->KEY);
silc_free(ske->KEY);
ske->KEY = NULL;
silc_ske_payload_ke_free(ske->ke2_payload);
must not be called until the keys are processed like the protocol
defines. This function is for both initiator and responder. */
-SilcSKEStatus silc_ske_end(SilcSKE ske,
- SilcSKESendPacketCb send_packet,
- void *context)
+SilcSKEStatus silc_ske_end(SilcSKE ske)
{
- SilcBuffer packet;
+ SilcBufferStruct packet;
+ unsigned char data[4];
SILC_LOG_DEBUG(("Start"));
- packet = silc_buffer_alloc(4);
- silc_buffer_pull_tail(packet, SILC_BUFFER_END(packet));
- silc_buffer_format(packet,
- SILC_STR_UI_INT((uint32)SILC_SKE_STATUS_OK),
- SILC_STR_END);
+ SILC_PUT32_MSB((SilcUInt32)SILC_SKE_STATUS_OK, data);
+ silc_buffer_set(&packet, data, 4);
- if (send_packet)
- (*send_packet)(ske, packet, SILC_PACKET_SUCCESS, context);
-
- silc_buffer_free(packet);
+ if (ske->callbacks->send_packet)
+ (*ske->callbacks->send_packet)(ske, &packet, SILC_PACKET_SUCCESS,
+ ske->callbacks->context);
return SILC_SKE_STATUS_OK;
}
while performing the protocol. The status argument is the error
status and it is sent to the remote end. */
-SilcSKEStatus silc_ske_abort(SilcSKE ske, SilcSKEStatus status,
- SilcSKESendPacketCb send_packet,
- void *context)
+SilcSKEStatus silc_ske_abort(SilcSKE ske, SilcSKEStatus status)
{
- SilcBuffer packet;
+ SilcBufferStruct packet;
+ unsigned char data[4];
SILC_LOG_DEBUG(("Start"));
- packet = silc_buffer_alloc(4);
- silc_buffer_pull_tail(packet, SILC_BUFFER_END(packet));
- silc_buffer_format(packet,
- SILC_STR_UI_INT((uint32)status),
- SILC_STR_END);
+ if (status > SILC_SKE_STATUS_INVALID_COOKIE)
+ status = SILC_SKE_STATUS_BAD_PAYLOAD;
- if (send_packet)
- (*send_packet)(ske, packet, SILC_PACKET_FAILURE, context);
+ SILC_PUT32_MSB((SilcUInt32)status, data);
+ silc_buffer_set(&packet, data, 4);
- silc_buffer_free(packet);
+ if (ske->callbacks->send_packet)
+ (*ske->callbacks->send_packet)(ske, &packet, SILC_PACKET_FAILURE,
+ ske->callbacks->context);
return SILC_SKE_STATUS_OK;
}
as, this function is called by the caller of the protocol and not
by the protocol itself. */
-SilcSKEStatus
+SilcSKEStatus
silc_ske_assemble_security_properties(SilcSKE ske,
- unsigned char flags,
- char *version,
+ SilcSKESecurityPropertyFlag flags,
+ const char *version,
SilcSKEStartPayload **return_payload)
{
SilcSKEStartPayload *rp;
rp = silc_calloc(1, sizeof(*rp));
/* Set flags */
- rp->flags = 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(ske->rng);
+ rp->cookie[i] = silc_rng_get_byte_fast(ske->rng);
rp->cookie_len = SILC_SKE_COOKIE_LEN;
/* Put version */
/* XXX */
/* Get supported compression algorithms */
- rp->comp_alg_list = "";
- rp->comp_alg_len = 0;
+ rp->comp_alg_list = strdup("none");
+ rp->comp_alg_len = strlen("none");
- rp->len = 1 + 1 + 2 + SILC_SKE_COOKIE_LEN +
+ 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->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_payload = rp;
return SILC_SKE_STATUS_OK;
}
-/* Selects the supported security properties from the remote end's Key
+/* Selects the supported security properties from the remote end's Key
Exchange Start Payload. */
-SilcSKEStatus
+SilcSKEStatus
silc_ske_select_security_properties(SilcSKE ske,
- char *version,
+ const char *version,
SilcSKEStartPayload *payload,
SilcSKEStartPayload *remote_payload)
{
rp = remote_payload;
/* Check version string */
- status = silc_ske_check_version(ske, rp->version, rp->version_len);
- if (status != SILC_SKE_STATUS_OK) {
- ske->status = status;
- return status;
+ if (ske->callbacks->check_version) {
+ status = ske->callbacks->check_version(ske, rp->version,
+ rp->version_len,
+ ske->callbacks->context);
+ if (status != SILC_SKE_STATUS_OK) {
+ ske->status = status;
+ return status;
+ }
}
+ ske->remote_version = silc_memdup(rp->version, rp->version_len);
+
/* Flags are returned unchanged. */
payload->flags = rp->flags;
- /* Take cookie */
+ /* Take cookie, we must return it to sender unmodified. */
payload->cookie = silc_calloc(SILC_SKE_COOKIE_LEN, sizeof(unsigned char));
payload->cookie_len = SILC_SKE_COOKIE_LEN;
memcpy(payload->cookie, rp->cookie, SILC_SKE_COOKIE_LEN);
SILC_LOG_DEBUG(("Proposed KE group `%s'", item));
- if (silc_ske_get_group_by_name(item, NULL) == SILC_SKE_STATUS_OK) {
+ if (silc_ske_group_get_by_name(item, NULL) == SILC_SKE_STATUS_OK) {
SILC_LOG_DEBUG(("Found KE group `%s'", item));
payload->ke_grp_len = len;
payload->hmac_alg_list = strdup(rp->hmac_alg_list);
}
-#if 0
/* Get supported compression algorithms */
- cp = rp->hash_alg_list;
+ cp = rp->comp_alg_list;
if (cp && strchr(cp, ',')) {
while(cp) {
char *item;
item = silc_calloc(len + 1, sizeof(char));
memcpy(item, cp, len);
- SILC_LOG_DEBUG(("Proposed hash alg `%s'", item));
+ SILC_LOG_DEBUG(("Proposed Compression `%s'", item));
- if (silc_hash_is_supported(item) == TRUE) {
- SILC_LOG_DEBUG(("Found hash alg `%s'", item));
-
- payload->hash_alg_len = len;
- payload->hash_alg_list = item;
+#if 1
+ if (!strcmp(item, "none")) {
+ SILC_LOG_DEBUG(("Found Compression `%s'", item));
+ payload->comp_alg_len = len;
+ payload->comp_alg_list = item;
break;
}
+#else
+ if (silc_hmac_is_supported(item) == TRUE) {
+ SILC_LOG_DEBUG(("Found Compression `%s'", item));
+ payload->comp_alg_len = len;
+ payload->comp_alg_list = item;
+ break;
+ }
+#endif
cp += len;
if (strlen(cp) == 0)
if (item)
silc_free(item);
}
-
- if (!payload->hash_alg_len && !payload->hash_alg_list) {
- SILC_LOG_DEBUG(("Could not find supported hash alg"));
- silc_ske_abort(ske, SILC_SKE_STATUS_UNKNOWN_HASH_FUNCTION);
- silc_free(payload->ke_grp_list);
- silc_free(payload->pkcs_alg_list);
- silc_free(payload->enc_alg_list);
- silc_free(payload);
- return;
- }
- } else {
-
}
-#endif
- payload->len = 1 + 1 + 2 + SILC_SKE_COOKIE_LEN +
- 2 + payload->version_len +
- 2 + payload->ke_grp_len + 2 + payload->pkcs_alg_len +
- 2 + payload->enc_alg_len + 2 + payload->hash_alg_len +
+ payload->len = 1 + 1 + 2 + SILC_SKE_COOKIE_LEN +
+ 2 + payload->version_len +
+ 2 + payload->ke_grp_len + 2 + payload->pkcs_alg_len +
+ 2 + payload->enc_alg_len + 2 + payload->hash_alg_len +
2 + payload->hmac_alg_len + 2 + payload->comp_alg_len;
return SILC_SKE_STATUS_OK;
/* Creates random number such that 1 < rnd < n and at most length
of len bits. The rnd sent as argument must be initialized. */
-SilcSKEStatus silc_ske_create_rnd(SilcSKE ske, SilcInt n,
- uint32 len,
- SilcInt *rnd)
+static SilcSKEStatus silc_ske_create_rnd(SilcSKE ske, SilcMPInt *n,
+ SilcUInt32 len,
+ SilcMPInt *rnd)
{
SilcSKEStatus status = SILC_SKE_STATUS_OK;
unsigned char *string;
+ SilcUInt32 l;
+
+ if (!len)
+ return SILC_SKE_STATUS_ERROR;
SILC_LOG_DEBUG(("Creating random number"));
+ l = ((len - 1) / 8);
+
/* Get the random number as string */
- string = silc_rng_get_rn_data(ske->rng, (len / 8));
+ string = silc_rng_get_rn_data(ske->rng, l);
if (!string)
- return SILC_SKE_STATUS_ERROR;
+ return SILC_SKE_STATUS_OUT_OF_MEMORY;
/* Decode the string into a MP integer */
- silc_mp_bin2mp(string, (len / 8), rnd);
+ silc_mp_bin2mp(string, l, rnd);
silc_mp_mod_2exp(rnd, rnd, len);
/* Checks */
if (silc_mp_cmp_ui(rnd, 1) < 0)
status = SILC_SKE_STATUS_ERROR;
-
- if (silc_mp_cmp(rnd, &n) >= 0)
+ if (silc_mp_cmp(rnd, n) >= 0)
status = SILC_SKE_STATUS_ERROR;
- memset(string, 'F', (len / 8));
+ memset(string, 'F', l);
silc_free(string);
return status;
hash value defined in the protocol. If it is FALSE then this is used
to create the HASH value defined by the protocol. */
-SilcSKEStatus silc_ske_make_hash(SilcSKE ske,
- unsigned char *return_hash,
- uint32 *return_hash_len,
- int initiator)
+static SilcSKEStatus silc_ske_make_hash(SilcSKE ske,
+ unsigned char *return_hash,
+ SilcUInt32 *return_hash_len,
+ int initiator)
{
SilcSKEStatus status = SILC_SKE_STATUS_OK;
SilcBuffer buf;
unsigned char *e, *f, *KEY;
- uint32 e_len, f_len, KEY_len;
+ SilcUInt32 e_len, f_len, KEY_len;
int ret;
SILC_LOG_DEBUG(("Start"));
e = silc_mp_mp2bin(&ske->ke1_payload->x, 0, &e_len);
f = silc_mp_mp2bin(&ske->ke2_payload->x, 0, &f_len);
KEY = silc_mp_mp2bin(ske->KEY, 0, &KEY_len);
-
- buf = silc_buffer_alloc(ske->start_payload_copy->len +
- ske->pk_len + e_len + f_len + KEY_len);
- silc_buffer_pull_tail(buf, SILC_BUFFER_END(buf));
-
+
/* Format the buffer used to compute the hash value */
- ret =
- silc_buffer_format(buf,
- SILC_STR_UI_XNSTRING(ske->start_payload_copy->data,
- ske->start_payload_copy->len),
- SILC_STR_UI_XNSTRING(ske->pk, ske->pk_len),
- SILC_STR_UI_XNSTRING(e, e_len),
- SILC_STR_UI_XNSTRING(f, f_len),
- SILC_STR_UI_XNSTRING(KEY, KEY_len),
- SILC_STR_END);
+ buf = silc_buffer_alloc_size(ske->start_payload_copy->len +
+ ske->ke2_payload->pk_len +
+ ske->ke1_payload->pk_len +
+ e_len + f_len + KEY_len);
+ if (!buf)
+ return SILC_SKE_STATUS_OUT_OF_MEMORY;
+
+ /* Initiator is not required to send its public key */
+ if (!ske->ke1_payload->pk_data) {
+ ret =
+ silc_buffer_format(buf,
+ SILC_STR_UI_XNSTRING(ske->start_payload_copy->
+ data,
+ ske->start_payload_copy->
+ len),
+ SILC_STR_UI_XNSTRING(ske->ke2_payload->pk_data,
+ ske->ke2_payload->pk_len),
+ SILC_STR_UI_XNSTRING(e, e_len),
+ SILC_STR_UI_XNSTRING(f, f_len),
+ SILC_STR_UI_XNSTRING(KEY, KEY_len),
+ SILC_STR_END);
+ } else {
+ ret =
+ silc_buffer_format(buf,
+ SILC_STR_UI_XNSTRING(ske->start_payload_copy->
+ data,
+ ske->start_payload_copy->
+ len),
+ SILC_STR_UI_XNSTRING(ske->ke2_payload->pk_data,
+ ske->ke2_payload->pk_len),
+ SILC_STR_UI_XNSTRING(ske->ke1_payload->pk_data,
+ ske->ke1_payload->pk_len),
+ SILC_STR_UI_XNSTRING(e, e_len),
+ SILC_STR_UI_XNSTRING(f, f_len),
+ SILC_STR_UI_XNSTRING(KEY, KEY_len),
+ SILC_STR_END);
+ }
if (ret == -1) {
silc_buffer_free(buf);
memset(e, 0, e_len);
} else {
e = silc_mp_mp2bin(&ske->ke1_payload->x, 0, &e_len);
- buf = silc_buffer_alloc(ske->start_payload_copy->len +
- ske->pk_len + e_len);
- silc_buffer_pull_tail(buf, SILC_BUFFER_END(buf));
-
+ buf = silc_buffer_alloc_size(ske->start_payload_copy->len +
+ ske->ke1_payload->pk_len + e_len);
+ if (!buf)
+ return SILC_SKE_STATUS_OUT_OF_MEMORY;
+
/* Format the buffer used to compute the hash value */
- ret =
+ ret =
silc_buffer_format(buf,
SILC_STR_UI_XNSTRING(ske->start_payload_copy->data,
ske->start_payload_copy->len),
- SILC_STR_UI_XNSTRING(ske->pk, ske->pk_len),
+ SILC_STR_UI_XNSTRING(ske->ke1_payload->pk_data,
+ ske->ke1_payload->pk_len),
SILC_STR_UI_XNSTRING(e, e_len),
SILC_STR_END);
if (ret == -1) {
/* Make the hash */
silc_hash_make(ske->prop->hash, buf->data, buf->len, return_hash);
- *return_hash_len = ske->prop->hash->hash->hash_len;
+ *return_hash_len = silc_hash_len(ske->prop->hash);
if (initiator == FALSE) {
SILC_LOG_HEXDUMP(("HASH"), return_hash, *return_hash_len);
return status;
}
-/* Processes the provided key material `data' as the SILC protocol
- specification specifies. */
+/* Processes the provided key material `data' as the SILC protocol
+ specification defines. */
-SilcSKEStatus
+SilcSKEStatus
silc_ske_process_key_material_data(unsigned char *data,
- uint32 data_len,
- uint32 req_iv_len,
- uint32 req_enc_key_len,
- uint32 req_hmac_key_len,
+ SilcUInt32 data_len,
+ SilcUInt32 req_iv_len,
+ SilcUInt32 req_enc_key_len,
+ SilcUInt32 req_hmac_key_len,
SilcHash hash,
SilcSKEKeyMaterial *key)
{
SilcBuffer buf;
- unsigned char hashd[32];
- uint32 hash_len = req_hmac_key_len;
- uint32 enc_key_len = req_enc_key_len / 8;
+ unsigned char hashd[SILC_HASH_MAXLEN];
+ SilcUInt32 hash_len = req_hmac_key_len;
+ SilcUInt32 enc_key_len = req_enc_key_len / 8;
SILC_LOG_DEBUG(("Start"));
if (!req_iv_len || !req_enc_key_len || !req_hmac_key_len)
return SILC_SKE_STATUS_ERROR;
- buf = silc_buffer_alloc(1 + data_len);
- silc_buffer_pull_tail(buf, SILC_BUFFER_END(buf));
+ buf = silc_buffer_alloc_size(1 + data_len);
+ if (!buf)
+ return SILC_SKE_STATUS_OUT_OF_MEMORY;
silc_buffer_format(buf,
SILC_STR_UI_CHAR(0),
SILC_STR_UI_XNSTRING(data, data_len),
buf->data[0] = 2;
if (enc_key_len > hash_len) {
SilcBuffer dist;
- unsigned char k1[32], k2[32], k3[32];
+ unsigned char k1[SILC_HASH_MAXLEN], k2[SILC_HASH_MAXLEN],
+ k3[SILC_HASH_MAXLEN];
unsigned char *dtmp;
-
+
/* XXX */
if (enc_key_len > (3 * hash_len))
return SILC_SKE_STATUS_ERROR;
-
+
/* Take first round */
memset(k1, 0, sizeof(k1));
silc_hash_make(hash, buf->data, buf->len, k1);
-
+
/* Take second round */
- dist = silc_buffer_alloc(data_len + hash_len);
- silc_buffer_pull_tail(dist, SILC_BUFFER_END(dist));
+ dist = silc_buffer_alloc_size(data_len + hash_len);
+ if (!dist)
+ return SILC_SKE_STATUS_OUT_OF_MEMORY;
silc_buffer_format(dist,
SILC_STR_UI_XNSTRING(data, data_len),
SILC_STR_UI_XNSTRING(k1, hash_len),
SILC_STR_END);
memset(k2, 0, sizeof(k2));
silc_hash_make(hash, dist->data, dist->len, k2);
-
+
/* Take third round */
dist = silc_buffer_realloc(dist, data_len + hash_len + hash_len);
silc_buffer_pull_tail(dist, hash_len);
dtmp = silc_calloc((3 * hash_len), sizeof(unsigned char));
memcpy(dtmp, k1, hash_len);
memcpy(dtmp + hash_len, k2, hash_len);
- memcpy(dtmp + hash_len, k3, hash_len);
+ memcpy(dtmp + hash_len + hash_len, k3, hash_len);
key->send_enc_key = silc_calloc(enc_key_len, sizeof(unsigned char));
memcpy(key->send_enc_key, dtmp, enc_key_len);
memset(k2, 0, sizeof(k2));
memset(k3, 0, sizeof(k3));
silc_free(dtmp);
+ silc_buffer_clear(dist);
silc_buffer_free(dist);
} else {
/* Take normal hash as key */
buf->data[0] = 3;
if (enc_key_len > hash_len) {
SilcBuffer dist;
- unsigned char k1[32], k2[32], k3[32];
+ unsigned char k1[SILC_HASH_MAXLEN], k2[SILC_HASH_MAXLEN],
+ k3[SILC_HASH_MAXLEN];
unsigned char *dtmp;
-
+
/* XXX */
if (enc_key_len > (3 * hash_len))
return SILC_SKE_STATUS_ERROR;
-
+
/* Take first round */
memset(k1, 0, sizeof(k1));
silc_hash_make(hash, buf->data, buf->len, k1);
-
+
/* Take second round */
- dist = silc_buffer_alloc(data_len + hash_len);
- silc_buffer_pull_tail(dist, SILC_BUFFER_END(dist));
+ dist = silc_buffer_alloc_size(data_len + hash_len);
+ if (!dist)
+ return SILC_SKE_STATUS_OUT_OF_MEMORY;
silc_buffer_format(dist,
SILC_STR_UI_XNSTRING(data, data_len),
SILC_STR_UI_XNSTRING(k1, hash_len),
SILC_STR_END);
memset(k2, 0, sizeof(k2));
silc_hash_make(hash, dist->data, dist->len, k2);
-
+
/* Take third round */
dist = silc_buffer_realloc(dist, data_len + hash_len + hash_len);
silc_buffer_pull_tail(dist, hash_len);
dtmp = silc_calloc((3 * hash_len), sizeof(unsigned char));
memcpy(dtmp, k1, hash_len);
memcpy(dtmp + hash_len, k2, hash_len);
- memcpy(dtmp + hash_len, k3, hash_len);
+ memcpy(dtmp + hash_len + hash_len, k3, hash_len);
key->receive_enc_key = silc_calloc(enc_key_len, sizeof(unsigned char));
memcpy(key->receive_enc_key, dtmp, enc_key_len);
memset(k2, 0, sizeof(k2));
memset(k3, 0, sizeof(k3));
silc_free(dtmp);
+ silc_buffer_clear(dist);
silc_buffer_free(dist);
} else {
/* Take normal hash as key */
key->enc_key_len = req_enc_key_len;
}
- /* Take HMAC key */
+ /* Take HMAC keys */
memset(hashd, 0, sizeof(hashd));
buf->data[0] = 4;
silc_hash_make(hash, buf->data, buf->len, hashd);
- key->hmac_key = silc_calloc(req_hmac_key_len, sizeof(unsigned char));
- memcpy(key->hmac_key, hashd, req_hmac_key_len);
+ key->send_hmac_key = silc_calloc(req_hmac_key_len, sizeof(unsigned char));
+ memcpy(key->send_hmac_key, hashd, req_hmac_key_len);
+ memset(hashd, 0, sizeof(hashd));
+ buf->data[0] = 5;
+ silc_hash_make(hash, buf->data, buf->len, hashd);
+ key->receive_hmac_key = silc_calloc(req_hmac_key_len, sizeof(unsigned char));
+ memcpy(key->receive_hmac_key, hashd, req_hmac_key_len);
key->hmac_key_len = req_hmac_key_len;
+ memset(hashd, 0, sizeof(hashd));
+ silc_buffer_clear(buf);
silc_buffer_free(buf);
return SILC_SKE_STATUS_OK;
/* Processes negotiated key material as protocol specifies. This returns
the actual keys to be used in the SILC. */
-SilcSKEStatus silc_ske_process_key_material(SilcSKE ske,
- uint32 req_iv_len,
- uint32 req_enc_key_len,
- uint32 req_hmac_key_len,
+SilcSKEStatus silc_ske_process_key_material(SilcSKE ske,
+ SilcUInt32 req_iv_len,
+ SilcUInt32 req_enc_key_len,
+ SilcUInt32 req_hmac_key_len,
SilcSKEKeyMaterial *key)
{
SilcSKEStatus status;
SilcBuffer buf;
unsigned char *tmpbuf;
- uint32 klen;
+ SilcUInt32 klen;
/* Encode KEY to binary data */
tmpbuf = silc_mp_mp2bin(ske->KEY, 0, &klen);
- buf = silc_buffer_alloc(klen + ske->hash_len);
- silc_buffer_pull_tail(buf, SILC_BUFFER_END(buf));
+ buf = silc_buffer_alloc_size(klen + ske->hash_len);
+ if (!buf)
+ return SILC_SKE_STATUS_OUT_OF_MEMORY;
silc_buffer_format(buf,
SILC_STR_UI_XNSTRING(tmpbuf, klen),
SILC_STR_UI_XNSTRING(ske->hash, ske->hash_len),
/* Process the key material */
status = silc_ske_process_key_material_data(buf->data, buf->len,
req_iv_len, req_enc_key_len,
- req_hmac_key_len,
+ req_hmac_key_len,
ske->prop->hash, key);
memset(tmpbuf, 0, klen);
silc_free(tmpbuf);
+ silc_buffer_clear(buf);
silc_buffer_free(buf);
return status;
memset(key->receive_enc_key, 0, key->enc_key_len / 8);
silc_free(key->receive_enc_key);
}
- if (key->hmac_key) {
- memset(key->hmac_key, 0, key->hmac_key_len);
- silc_free(key->hmac_key);
+ if (key->send_hmac_key) {
+ memset(key->send_hmac_key, 0, key->hmac_key_len);
+ silc_free(key->send_hmac_key);
+ }
+ if (key->receive_hmac_key) {
+ memset(key->receive_hmac_key, 0, key->hmac_key_len);
+ silc_free(key->receive_hmac_key);
}
silc_free(key);
}
+
+const char *silc_ske_status_string[] =
+{
+ /* Official */
+ "Ok",
+ "Unkown error occurred",
+ "Bad payload in packet",
+ "Unsupported group",
+ "Unsupported cipher",
+ "Unsupported PKCS",
+ "Unsupported hash function",
+ "Unsupported HMAC",
+ "Unsupported public key (or certificate)",
+ "Incorrect signature",
+ "Bad or unsupported version",
+ "Invalid cookie",
+
+ /* Other errors */
+ "Pending",
+ "Remote did not provide public key",
+ "Key exchange protocol is not active",
+ "Bad reserved field in packet",
+ "Bad payload length in packet",
+ "Error computing signature",
+ "System out of memory",
+
+ NULL
+};
+
+/* Maps status to readable string and returns the string. If string is not
+ found and empty character string ("") is returned. */
+
+const char *silc_ske_map_status(SilcSKEStatus status)
+{
+ int i;
+
+ for (i = 0; silc_ske_status_string[i]; i++)
+ if (status == i)
+ return silc_ske_status_string[i];
+
+ return "";
+}
+
+/* Parses remote host's version string. */
+
+bool silc_ske_parse_version(SilcSKE ske,
+ SilcUInt32 *protocol_version,
+ char **protocol_version_string,
+ SilcUInt32 *software_version,
+ char **software_version_string,
+ char **vendor_version)
+{
+ return silc_parse_version_string(ske->remote_version,
+ protocol_version,
+ protocol_version_string,
+ software_version,
+ software_version_string,
+ vendor_version);
+}