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Refactor signing backend (#690)

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Cleaned up the AES driver and removed some cppcheck isues
in the process.
This commit is contained in:
Patrick Fallberg
2016-12-25 16:12:40 +01:00
committed by Henrik Ekblad
parent 61e6cecb3f
commit 1040fbebc5
27 changed files with 398 additions and 14004 deletions
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core/MySigning.cpp
+286 -247
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@@ -36,6 +36,9 @@
#if defined(MY_SIGNING_GW_REQUEST_SIGNATURES_FROM_ALL) && !defined(MY_SIGNING_REQUEST_SIGNATURES)
#error You have to require signatures if you want to require signatures from all (also enable MY_SIGNING_REQUEST_SIGNATURES in your gateway)
#endif
#if defined(MY_SIGNING_SOFT) && defined(MY_SIGNING_ATSHA204)
#error You have to pick one and only one signing backend
#endif
#ifdef MY_SIGNING_FEATURE
uint8_t _doSign[32]; // Bitfield indicating which sensors require signed communication
uint8_t _doWhitelist[32]; // Bitfield indicating which sensors require serial salted signatures
@@ -47,23 +50,17 @@ static uint8_t nof_nonce_requests = 0;
static uint8_t nof_failed_verifications = 0;
#endif
// Status when waiting for signing nonce in signerProcessInternal
// Status when waiting for signing nonce in signerSignMsg
enum { SIGN_WAITING_FOR_NONCE = 0, SIGN_OK = 1 };
// Macros for manipulating signing requirement table
// Macros for manipulating signing requirement tables
#define DO_SIGN(node) (~_doSign[node>>3]&(1<<node%8))
#define SET_SIGN(node) (_doSign[node>>3]&=~(1<<node%8))
#define CLEAR_SIGN(node) (_doSign[node>>3]|=(1<<node%8))
#define DO_WHITELIST(node) (~_doWhitelist[node>>3]&(1<<node%8))
#define SET_WHITELIST(node) (_doWhitelist[node>>3]&=~(1<<node%8))
#define CLEAR_WHITELIST(node) (_doWhitelist[node>>3]|=(1<<node%8))
/*
* Stores signing identifier and a new nonce in provided message for signing operations.
*
* All space in message payload buffer is used for signing identifier and nonce.
* Returns false if subsystem is busy processing an ongoing signing operation.
* If successful, this marks the start of a signing operation at the receiving side so
* implementation is expected to do any necessary initializations within this call.
* This function is typically called as action when receiving a I_NONCE_REQUEST message.
*/
#if defined(MY_SIGNING_SOFT)
extern void signerAtsha204SoftInit(void);
extern bool signerAtsha204SoftCheckTimer(void);
@@ -71,53 +68,34 @@ extern bool signerAtsha204SoftGetNonce(MyMessage &msg);
extern void signerAtsha204SoftPutNonce(MyMessage &msg);
extern bool signerAtsha204SoftVerifyMsg(MyMessage &msg);
extern bool signerAtsha204SoftSignMsg(MyMessage &msg);
#endif
#if defined(MY_SIGNING_ATSHA204)
#define signerBackendInit signerAtsha204SoftInit
#define signerBackendCheckTimer signerAtsha204SoftCheckTimer
#define signerBackendGetNonce signerAtsha204SoftGetNonce
#define signerBackendPutNonce signerAtsha204SoftPutNonce
#define signerBackendVerifyMsg signerAtsha204SoftVerifyMsg
#define signerBackendSignMsg signerAtsha204SoftSignMsg
#elif defined(MY_SIGNING_ATSHA204)
extern void signerAtsha204Init(void);
extern bool signerAtsha204CheckTimer(void);
extern bool signerAtsha204GetNonce(MyMessage &msg);
extern void signerAtsha204PutNonce(MyMessage &msg);
extern bool signerAtsha204VerifyMsg(MyMessage &msg);
extern bool signerAtsha204SignMsg(MyMessage &msg);
#define signerBackendInit signerAtsha204Init
#define signerBackendCheckTimer signerAtsha204CheckTimer
#define signerBackendGetNonce signerAtsha204GetNonce
#define signerBackendPutNonce signerAtsha204PutNonce
#define signerBackendVerifyMsg signerAtsha204VerifyMsg
#define signerBackendSignMsg signerAtsha204SignMsg
#endif
// Helper function to centralize signing/verification exceptions
static bool skipSign(MyMessage &msg)
{
if mGetAck(msg) {
SIGN_DEBUG(PSTR("Skipping security for ACK on command %d type %d\n"), mGetCommand(msg), msg.type);
return true;
} else if (mGetCommand(msg) == C_INTERNAL &&
(msg.type == I_NONCE_REQUEST || msg.type == I_NONCE_RESPONSE ||
msg.type == I_SIGNING_PRESENTATION ||
msg.type == I_ID_REQUEST || msg.type == I_ID_RESPONSE ||
msg.type == I_FIND_PARENT_REQUEST || msg.type == I_FIND_PARENT_RESPONSE ||
msg.type == I_HEARTBEAT_REQUEST || msg.type == I_HEARTBEAT_RESPONSE ||
msg.type == I_PING || msg.type == I_PONG ||
msg.type == I_REGISTRATION_REQUEST )) {
SIGN_DEBUG(PSTR("Skipping security for command %d type %d\n"), mGetCommand(msg), msg.type);
return true;
} else if (mGetCommand(msg) == C_STREAM &&
(msg.type == ST_FIRMWARE_REQUEST || msg.type == ST_FIRMWARE_RESPONSE ||
msg.type == ST_SOUND || msg.type == ST_IMAGE)) {
SIGN_DEBUG(PSTR("Skipping security for command %d type %d\n"), mGetCommand(msg), msg.type);
return true;
} else {
return false;
}
}
static bool skipSign(MyMessage &msg);
#else // not MY_SIGNING_FEATURE
#define signerBackendCheckTimer() true
#endif // MY_SIGNING_FEATURE
// Helper to prepare a signing presentation message
static void prepareSigningPresentation(MyMessage &msg, uint8_t destination)
{
// Only supports version 1 for now
(void)build(msg, destination, NODE_SENSOR_ID, C_INTERNAL, I_SIGNING_PRESENTATION).set("");
mSetLength(msg, 2);
mSetPayloadType(msg, P_CUSTOM); // displayed as hex
msg.data[0] = SIGNING_PRESENTATION_VERSION_1;
msg.data[1] = 0;
}
static void prepareSigningPresentation(MyMessage &msg, uint8_t destination);
static bool signerInternalProcessPresentation(MyMessage &msg);
static bool signerInternalProcessNonceRequest(MyMessage &msg);
static bool signerInternalProcessNonceResponse(MyMessage &msg);
void signerInit(void)
{
@@ -130,12 +108,7 @@ void signerInit(void)
hwReadConfigBlock((void*)_doWhitelist, (void*)EEPROM_WHITELIST_REQUIREMENT_TABLE_ADDRESS,
sizeof(_doWhitelist));
#if defined(MY_SIGNING_SOFT)
signerAtsha204SoftInit();
#endif
#if defined(MY_SIGNING_ATSHA204)
signerAtsha204Init();
#endif
signerBackendInit();
#endif
}
@@ -164,212 +137,92 @@ void signerPresentation(MyMessage &msg, uint8_t destination)
bool signerProcessInternal(MyMessage &msg)
{
uint8_t sender = msg.sender;
(void)sender;
#if !defined(MY_SIGNING_FEATURE)
if (msg.type == I_SIGNING_PRESENTATION) {
#if defined(MY_GATEWAY_FEATURE)
// If we act as gateway and do not have the signing feature and receive a signing request we still
// need to do make sure the requester does not believe the gateway still require signatures
prepareSigningPresentation(msg, sender);
SIGN_DEBUG(
PSTR("Informing node %d that we do not require signatures because we do not support it\n"),
sender);
if (!_sendRoute(msg)) {
SIGN_DEBUG(PSTR("Failed to transmit signing presentation!\n"));
}
return true; // No need to further process I_SIGNING_PRESENTATION in this case
#else
// If we act as a node and do not have the signing feature then we just silently drop any signing
// presentation messages received
SIGN_DEBUG(PSTR("Received signing presentation, but signing is not supported (message ignored)\n"));
return true;
#endif
bool ret;
switch (msg.type) {
case I_SIGNING_PRESENTATION:
ret = signerInternalProcessPresentation(msg);
break;
case I_NONCE_REQUEST:
ret = signerInternalProcessNonceRequest(msg);
break;
case I_NONCE_RESPONSE:
ret = signerInternalProcessNonceResponse(msg);
break;
default:
ret = false; // Let the transport process this message further as it is not related to signing
break;
}
#elif defined(MY_SIGNING_FEATURE)
if (msg.type == I_NONCE_REQUEST) {
#if defined(MY_NODE_LOCK_FEATURE)
nof_nonce_requests++;
SIGN_DEBUG(PSTR("Nonce requests left until lockdown: %d\n"),
MY_NODE_LOCK_COUNTER_MAX-nof_nonce_requests);
if (nof_nonce_requests >= MY_NODE_LOCK_COUNTER_MAX) {
_nodeLock("TMNR"); //Too many nonces requested
}
#endif
#if defined(MY_SIGNING_SOFT)
if (signerAtsha204SoftGetNonce(msg)) {
#endif
#if defined(MY_SIGNING_ATSHA204)
if (signerAtsha204GetNonce(msg)) {
#endif
if (!_sendRoute(build(msg, msg.sender, NODE_SENSOR_ID, C_INTERNAL, I_NONCE_RESPONSE))) {
SIGN_DEBUG(PSTR("Failed to transmit nonce!\n"));
} else {
SIGN_DEBUG(PSTR("Transmitted nonce\n"));
}
} else {
SIGN_DEBUG(PSTR("Failed to generate nonce!\n"));
}
return true; // No need to further process I_NONCE_REQUEST
} else if (msg.type == I_SIGNING_PRESENTATION) {
if (msg.data[0] != SIGNING_PRESENTATION_VERSION_1) {
SIGN_DEBUG(PSTR("Unsupported signing presentation version (%d)!\n"), msg.data[0]);
return true; // Just drop this presentation message
}
// We only handle version 1 here...
if (msg.data[1] & SIGNING_PRESENTATION_REQUIRE_SIGNATURES) {
// We received an indicator that the sender require us to sign all messages we send to it
SIGN_DEBUG(PSTR("Mark node %d as one that require signed messages\n"), msg.sender);
SET_SIGN(msg.sender);
} else {
// We received an indicator that the sender does not require us to sign all messages we send to it
SIGN_DEBUG(PSTR("Mark node %d as one that do not require signed messages\n"), msg.sender);
CLEAR_SIGN(msg.sender);
}
if (msg.data[1] & SIGNING_PRESENTATION_REQUIRE_WHITELISTING) {
// We received an indicator that the sender require us to salt signatures with serial
SIGN_DEBUG(PSTR("Mark node %d as one that require whitelisting\n"), msg.sender);
SET_WHITELIST(msg.sender);
} else {
// We received an indicator that the sender does not require us to sign all messages we send to it
SIGN_DEBUG(PSTR("Mark node %d as one that do not require whitelisting\n"), msg.sender);
CLEAR_WHITELIST(msg.sender);
}
// Save updated tables
hwWriteConfigBlock((void*)_doSign, (void*)EEPROM_SIGNING_REQUIREMENT_TABLE_ADDRESS,
sizeof(_doSign));
hwWriteConfigBlock((void*)_doWhitelist, (void*)EEPROM_WHITELIST_REQUIREMENT_TABLE_ADDRESS,
sizeof(_doWhitelist));
// Inform sender about our preference if we are a gateway, but only require signing if the sender
// required signing unless we explicitly configure it to
// We do not want a gateway to require signing from all nodes in a network just because it wants one node
// to sign it's messages unless we explicitly configure it to
#if defined(MY_GATEWAY_FEATURE)
prepareSigningPresentation(msg, sender);
#if defined(MY_SIGNING_REQUEST_SIGNATURES)
if (DO_SIGN(sender)) {
msg.data[1] |= SIGNING_PRESENTATION_REQUIRE_SIGNATURES;
}
#if defined(MY_SIGNING_GW_REQUEST_SIGNATURES_FROM_ALL)
msg.data[1] |= SIGNING_PRESENTATION_REQUIRE_SIGNATURES;
#endif
#endif
#if defined(MY_SIGNING_NODE_WHITELISTING)
if (DO_WHITELIST(sender)) {
msg.data[1] |= SIGNING_PRESENTATION_REQUIRE_WHITELISTING;
}
#if defined(MY_SIGNING_GW_REQUEST_SIGNATURES_FROM_ALL)
msg.data[1] |= SIGNING_PRESENTATION_REQUIRE_WHITELISTING;
#endif
#endif
if (msg.data[1] & SIGNING_PRESENTATION_REQUIRE_SIGNATURES) {
SIGN_DEBUG(PSTR("Informing node %d that we require signatures\n"), sender);
} else {
SIGN_DEBUG(PSTR("Informing node %d that we do not require signatures\n"), sender);
}
if (msg.data[1] & SIGNING_PRESENTATION_REQUIRE_WHITELISTING) {
SIGN_DEBUG(PSTR("Informing node %d that we require whitelisting\n"), sender);
} else {
SIGN_DEBUG(PSTR("Informing node %d that we do not require whitelisting\n"), sender);
}
if (!_sendRoute(msg)) {
SIGN_DEBUG(PSTR("Failed to transmit signing presentation!\n"));
}
#endif // MY_GATEWAY_FEATURE
return true; // No need to further process I_SIGNING_PRESENTATION
} else if (msg.type == I_NONCE_RESPONSE) {
// Proceed with signing if nonce has been received
SIGN_DEBUG(PSTR("Nonce received from %d. Proceeding with signing...\n"), sender);
if (sender != _msgSign.destination) {
SIGN_DEBUG(PSTR("Nonce did not come from the destination (%d) of the message to be signed! "
"It came from %d.\n"), _msgSign.destination, sender);
SIGN_DEBUG(PSTR("Silently discarding this nonce\n"));
return true; // No need to further process I_NONCE_RESPONSE
}
#if defined(MY_SIGNING_SOFT)
signerAtsha204SoftPutNonce(msg);
#endif
#if defined(MY_SIGNING_ATSHA204)
signerAtsha204PutNonce(msg);
#endif
#if defined(MY_SIGNING_SOFT)
if (!signerAtsha204SoftSignMsg(_msgSign)) {
#endif
#if defined(MY_SIGNING_ATSHA204)
if (!signerAtsha204SignMsg(_msgSign)) {
#endif
SIGN_DEBUG(PSTR("Failed to sign message!\n"));
} else {
SIGN_DEBUG(PSTR("Message signed\n"));
_signingNonceStatus = SIGN_OK; // _msgSign now contains the signed message pending transmission
}
return true; // No need to further process I_NONCE_RESPONSE
}
#endif // MY_SIGNING_FEATURE
return false;
return ret;
}
bool signerCheckTimer(void) {
#if defined(MY_SIGNING_SOFT)
return signerAtsha204SoftCheckTimer();
#elif defined(MY_SIGNING_ATSHA204)
return signerAtsha204CheckTimer();
#else
return true; // Without a configured backend, we always give "positive" results
#endif
bool signerCheckTimer(void)
{
return signerBackendCheckTimer();
}
bool signerSignMsg(MyMessage &msg) {
bool signerSignMsg(MyMessage &msg)
{
bool ret;
#if defined(MY_SIGNING_FEATURE)
// If destination is known to require signed messages and we are the sender,
// sign this message unless it is a handshake message
// sign this message unless it is identified as an exception
if (DO_SIGN(msg.destination) && msg.sender == getNodeId()) {
if (skipSign(msg)) {
return true;
ret = true;
} else {
// Send nonce-request
_signingNonceStatus=SIGN_WAITING_FOR_NONCE;
if (!_sendRoute(build(_msgSign, msg.destination, msg.sensor, C_INTERNAL,
I_NONCE_REQUEST).set(""))) {
SIGN_DEBUG(PSTR("Failed to transmit nonce request!\n"));
return false;
}
SIGN_DEBUG(PSTR("Nonce requested from %d. Waiting...\n"), msg.destination);
// We have to wait for the nonce to arrive before we can sign our original message
// Other messages could come in-between. We trust _process() takes care of them
unsigned long enter = hwMillis();
_msgSign = msg; // Copy the message to sign since message buffer might be touched in _process()
while (hwMillis() - enter < MY_VERIFICATION_TIMEOUT_MS &&
_signingNonceStatus==SIGN_WAITING_FOR_NONCE) {
_process();
}
if (hwMillis() - enter > MY_VERIFICATION_TIMEOUT_MS) {
SIGN_DEBUG(PSTR("Timeout waiting for nonce!\n"));
return false;
}
if (_signingNonceStatus == SIGN_OK) {
// process() received a nonce and signerProcessInternal successfully signed the message
msg = _msgSign; // Write the signed message back
SIGN_DEBUG(PSTR("Message to send has been signed\n"));
ret = false;
} else {
SIGN_DEBUG(PSTR("Message to send could not be signed!\n"));
return false;
SIGN_DEBUG(PSTR("Nonce requested from %d. Waiting...\n"), msg.destination);
// We have to wait for the nonce to arrive before we can sign our original message
// Other messages could come in-between. We trust _process() takes care of them
unsigned long enter = hwMillis();
_msgSign = msg; // Copy the message to sign since message buffer might be touched in _process()
while (hwMillis() - enter < MY_VERIFICATION_TIMEOUT_MS &&
_signingNonceStatus==SIGN_WAITING_FOR_NONCE) {
_process();
}
if (hwMillis() - enter > MY_VERIFICATION_TIMEOUT_MS) {
SIGN_DEBUG(PSTR("Timeout waiting for nonce!\n"));
ret = false;
} else {
if (_signingNonceStatus == SIGN_OK) {
// process() received a nonce and signerProcessInternal successfully signed the message
msg = _msgSign; // Write the signed message back
SIGN_DEBUG(PSTR("Message to send has been signed\n"));
ret = true;
// After this point, only the 'last' member of the message structure is allowed to be altered if the
// message has been signed, or signature will become invalid and the message rejected by the receiver
} else {
SIGN_DEBUG(PSTR("Message to send could not be signed!\n"));
ret = false;
}
}
}
// After this point, only the 'last' member of the message structure is allowed to be altered if the
// message has been signed, or signature will become invalid and the message rejected by the receiver
}
} else if (getNodeId() == msg.sender) {
mSetSigned(msg, 0); // Message is not supposed to be signed, make sure it is marked unsigned
SIGN_DEBUG(PSTR("Will not sign message for destination %d as it does not require it\n"),
msg.destination);
ret = true;
} else {
SIGN_DEBUG(PSTR("Will not sign message since it was from %d and we are %d\n"), msg.sender,
getNodeId());
ret = true;
}
#else
(void)msg;
ret = true;
#endif // MY_SIGNING_FEATURE
return true;
return ret;
}
bool signerVerifyMsg(MyMessage &msg) {
bool signerVerifyMsg(MyMessage &msg)
{
bool verificationResult = true;
// Before processing message, reject unsigned messages if signing is required and check signature
// (if it is signed and addressed to us)
@@ -390,14 +243,9 @@ bool signerVerifyMsg(MyMessage &msg) {
SIGN_DEBUG(PSTR("Message is not signed, but it should have been!\n"));
verificationResult = false;
} else {
#if defined(MY_SIGNING_SOFT)
verificationResult = signerAtsha204SoftVerifyMsg(msg);
#endif
#if defined(MY_SIGNING_ATSHA204)
verificationResult = signerAtsha204VerifyMsg(msg);
#endif
if (!verificationResult) {
if (!signerBackendVerifyMsg(msg)) {
SIGN_DEBUG(PSTR("Signature verification failed!\n"));
verificationResult = false;
}
#if defined(MY_NODE_LOCK_FEATURE)
if (verificationResult) {
@@ -425,23 +273,27 @@ bool signerVerifyMsg(MyMessage &msg) {
static uint8_t sha256_hash[32];
Sha256Class _soft_sha256;
void signerSha256Init(void) {
void signerSha256Init(void)
{
memset(sha256_hash, 0, 32);
_soft_sha256.init();
}
void signerSha256Update(const uint8_t* data, size_t sz) {
void signerSha256Update(const uint8_t* data, size_t sz)
{
for (size_t i = 0; i < sz; i++) {
_soft_sha256.write(data[i]);
}
}
uint8_t* signerSha256Final(void) {
uint8_t* signerSha256Final(void)
{
memcpy(sha256_hash, _soft_sha256.result(), 32);
return sha256_hash;
}
int signerMemcmp(const void* a, const void* b, size_t sz) {
int signerMemcmp(const void* a, const void* b, size_t sz)
{
int retVal;
size_t i;
int done = 0;
@@ -469,3 +321,190 @@ int signerMemcmp(const void* a, const void* b, size_t sz) {
}
return retVal;
}
#if defined(MY_SIGNING_FEATURE)
// Helper function to centralize signing/verification exceptions
static bool skipSign(MyMessage &msg)
{
bool ret;
if (mGetAck(msg)) {
SIGN_DEBUG(PSTR("Skipping security for ACK on command %d type %d\n"), mGetCommand(msg), msg.type);
ret = true;
} else if (mGetCommand(msg) == C_INTERNAL &&
(msg.type == I_NONCE_REQUEST || msg.type == I_NONCE_RESPONSE ||
msg.type == I_SIGNING_PRESENTATION ||
msg.type == I_ID_REQUEST || msg.type == I_ID_RESPONSE ||
msg.type == I_FIND_PARENT_REQUEST || msg.type == I_FIND_PARENT_RESPONSE ||
msg.type == I_HEARTBEAT_REQUEST || msg.type == I_HEARTBEAT_RESPONSE ||
msg.type == I_PING || msg.type == I_PONG ||
msg.type == I_REGISTRATION_REQUEST )) {
SIGN_DEBUG(PSTR("Skipping security for command %d type %d\n"), mGetCommand(msg), msg.type);
ret = true;
} else if (mGetCommand(msg) == C_STREAM &&
(msg.type == ST_FIRMWARE_REQUEST || msg.type == ST_FIRMWARE_RESPONSE ||
msg.type == ST_SOUND || msg.type == ST_IMAGE)) {
SIGN_DEBUG(PSTR("Skipping security for command %d type %d\n"), mGetCommand(msg), msg.type);
ret = true;
} else {
ret = false;
}
return ret;
}
#endif
// Helper to prepare a signing presentation message
static void prepareSigningPresentation(MyMessage &msg, uint8_t destination)
{
// Only supports version 1 for now
(void)build(msg, destination, NODE_SENSOR_ID, C_INTERNAL, I_SIGNING_PRESENTATION).set("");
mSetLength(msg, 2);
mSetPayloadType(msg, P_CUSTOM); // displayed as hex
msg.data[0] = SIGNING_PRESENTATION_VERSION_1;
msg.data[1] = 0;
}
// Helper to process presentation mesages
static bool signerInternalProcessPresentation(MyMessage &msg)
{
#if defined(MY_SIGNING_FEATURE)
if (msg.data[0] != SIGNING_PRESENTATION_VERSION_1) {
SIGN_DEBUG(PSTR("Unsupported signing presentation version (%d)!\n"), msg.data[0]);
return true; // Just drop this presentation message
}
// We only handle version 1 here...
if (msg.data[1] & SIGNING_PRESENTATION_REQUIRE_SIGNATURES) {
// We received an indicator that the sender require us to sign all messages we send to it
SIGN_DEBUG(PSTR("Mark node %d as one that require signed messages\n"), msg.sender);
SET_SIGN(msg.sender);
} else {
// We received an indicator that the sender does not require us to sign all messages we send to it
SIGN_DEBUG(PSTR("Mark node %d as one that do not require signed messages\n"), msg.sender);
CLEAR_SIGN(msg.sender);
}
if (msg.data[1] & SIGNING_PRESENTATION_REQUIRE_WHITELISTING) {
// We received an indicator that the sender require us to salt signatures with serial
SIGN_DEBUG(PSTR("Mark node %d as one that require whitelisting\n"), msg.sender);
SET_WHITELIST(msg.sender);
} else {
// We received an indicator that the sender does not require us to sign all messages we send to it
SIGN_DEBUG(PSTR("Mark node %d as one that do not require whitelisting\n"), msg.sender);
CLEAR_WHITELIST(msg.sender);
}
// Save updated tables
hwWriteConfigBlock((void*)_doSign, (void*)EEPROM_SIGNING_REQUIREMENT_TABLE_ADDRESS,
sizeof(_doSign));
hwWriteConfigBlock((void*)_doWhitelist, (void*)EEPROM_WHITELIST_REQUIREMENT_TABLE_ADDRESS,
sizeof(_doWhitelist));
// Inform sender about our preference if we are a gateway, but only require signing if the sender
// required signing unless we explicitly configure it to
#if defined(MY_GATEWAY_FEATURE)
prepareSigningPresentation(msg, msg.sender);
#if defined(MY_SIGNING_REQUEST_SIGNATURES)
#if defined(MY_SIGNING_GW_REQUEST_SIGNATURES_FROM_ALL)
msg.data[1] |= SIGNING_PRESENTATION_REQUIRE_SIGNATURES;
#else
if (DO_SIGN(msg.sender)) {
msg.data[1] |= SIGNING_PRESENTATION_REQUIRE_SIGNATURES;
}
#endif
#endif // MY_SIGNING_REQUEST_SIGNATURES
#if defined(MY_SIGNING_NODE_WHITELISTING)
#if defined(MY_SIGNING_GW_REQUEST_SIGNATURES_FROM_ALL)
msg.data[1] |= SIGNING_PRESENTATION_REQUIRE_WHITELISTING;
#else
if (DO_WHITELIST(msg.sender)) {
msg.data[1] |= SIGNING_PRESENTATION_REQUIRE_WHITELISTING;
}
#endif
#endif // MY_SIGNING_NODE_WHITELISTING
if (msg.data[1] & SIGNING_PRESENTATION_REQUIRE_SIGNATURES) {
SIGN_DEBUG(PSTR("Informing node %d that we require signatures\n"), msg.sender);
} else {
SIGN_DEBUG(PSTR("Informing node %d that we do not require signatures\n"), msg.sender);
}
if (msg.data[1] & SIGNING_PRESENTATION_REQUIRE_WHITELISTING) {
SIGN_DEBUG(PSTR("Informing node %d that we require whitelisting\n"), msg.sender);
} else {
SIGN_DEBUG(PSTR("Informing node %d that we do not require whitelisting\n"), msg.sender);
}
if (!_sendRoute(msg)) {
SIGN_DEBUG(PSTR("Failed to transmit signing presentation!\n"));
}
#endif // MY_GATEWAY_FEATURE
#else // not MY_SIGNING_FEATURE
#if defined(MY_GATEWAY_FEATURE)
// If we act as gateway and do not have the signing feature and receive a signing request we still
// need to do make sure the requester does not believe the gateway still require signatures
prepareSigningPresentation(msg, msg.sender);
SIGN_DEBUG(
PSTR("Informing node %d that we do not require signatures because we do not support it\n"),
msg.sender);
if (!_sendRoute(msg)) {
SIGN_DEBUG(PSTR("Failed to transmit signing presentation!\n"));
}
#else // not MY_GATEWAY_FEATURE
// If we act as a node and do not have the signing feature then we just silently drop any signing
// presentation messages received
(void)msg;
SIGN_DEBUG(PSTR("Received signing presentation, but signing is not supported (message ignored)\n"));
#endif // not MY_GATEWAY_FEATURE
#endif // not MY_SIGNING_FEATURE
return true; // No need to further process I_SIGNING_PRESENTATION
}
// Helper to process nonce request mesages
static bool signerInternalProcessNonceRequest(MyMessage &msg)
{
#if defined(MY_SIGNING_FEATURE)
#if defined(MY_NODE_LOCK_FEATURE)
nof_nonce_requests++;
SIGN_DEBUG(PSTR("Nonce requests left until lockdown: %d\n"),
MY_NODE_LOCK_COUNTER_MAX-nof_nonce_requests);
if (nof_nonce_requests >= MY_NODE_LOCK_COUNTER_MAX) {
_nodeLock("TMNR"); //Too many nonces requested
}
#endif // MY_NODE_LOCK_FEATURE
if (signerBackendGetNonce(msg)) {
if (!_sendRoute(build(msg, msg.sender, NODE_SENSOR_ID, C_INTERNAL, I_NONCE_RESPONSE))) {
SIGN_DEBUG(PSTR("Failed to transmit nonce!\n"));
} else {
SIGN_DEBUG(PSTR("Transmitted nonce\n"));
}
} else {
SIGN_DEBUG(PSTR("Failed to generate nonce!\n"));
}
#else // not MY_SIGNING_FEATURE
(void)msg;
SIGN_DEBUG(PSTR("Received nonce request, but signing is not supported (message ignored)\n"));
#endif // MY_SIGNING_FEATURE
return true; // No need to further process I_NONCE_REQUEST
}
// Helper to process nonce response mesages
static bool signerInternalProcessNonceResponse(MyMessage &msg)
{
#if defined(MY_SIGNING_FEATURE)
// Proceed with signing if nonce has been received
SIGN_DEBUG(PSTR("Nonce received from %d.\n"), msg.sender);
if (msg.sender != _msgSign.destination) {
SIGN_DEBUG(PSTR("Nonce did not come from the destination (%d) of the message to be signed! "
"It came from %d.\n"), _msgSign.destination, msg.sender);
SIGN_DEBUG(PSTR("Silently discarding this nonce\n"));
} else {
SIGN_DEBUG(PSTR("Proceeding with signing...\n"));
signerBackendPutNonce(msg);
if (!signerBackendSignMsg(_msgSign)) {
SIGN_DEBUG(PSTR("Failed to sign message!\n"));
} else {
SIGN_DEBUG(PSTR("Message signed\n"));
_signingNonceStatus = SIGN_OK; // _msgSign now contains the signed message pending transmission
}
}
#else
(void)msg;
SIGN_DEBUG(PSTR("Received nonce response, but signing is not supported (message ignored)\n"));
#endif
return true; // No need to further process I_NONCE_RESPONSE
}