int parseUserInformation(byte[] buffer, int bufPos, int maxBufPos, ref bool userInfoValid)
{
iecs.logger.LogDebug(String.Format("ACSE: parseUserInformation {0} {1}", bufPos, maxBufPos));
bool hasindirectReference = false;
bool isDataValid = false;
while (bufPos < maxBufPos)
{
byte tag = buffer[bufPos++];
int len = 0;
bufPos = IsoUtil.BerDecoder_decodeLength(buffer, ref len, bufPos, maxBufPos);
switch (tag)
{
case 0x02: /* indirect-reference */
nextReference = IsoUtil.BerDecoder_decodeUint32(buffer, len, bufPos);
bufPos += len;
hasindirectReference = true;
break;
case 0xa0: /* encoding */
isDataValid = true;
userDataBufferSize = len;
userDataBufferIndex = bufPos;
bufPos += len;
break;
default: /* ignore unknown tag */
bufPos += len;
break;
}
}
if (!hasindirectReference)
{
iecs.logger.LogDebug("ACSE: User data has no indirect reference!");
}
if (!isDataValid)
{
iecs.logger.LogDebug("ACSE: No valid user data");
}
if (hasindirectReference && isDataValid)
{
userInfoValid = true;
}
else
{
userInfoValid = false;
}
return(bufPos);
}
int parsePresentationContextDefinitionList(byte[] buffer, int totalLength, int bufPos)
{
int endPos = bufPos + totalLength;
while (bufPos < endPos)
{
byte tag = buffer[bufPos++];
int len = 0;
bufPos = IsoUtil.BerDecoder_decodeLength(buffer, ref len, bufPos, endPos);
switch (tag)
{
case 0x30:
iecs.logger.LogDebug("PRES: parse pcd entry");
bufPos = parsePCDLEntry(buffer, len, bufPos);
if (bufPos < 0)
{
return(-1);
}
break;
default:
iecs.logger.LogDebug("PRES: unknown tag in presentation-context-definition-list");
bufPos += len;
break;
}
}
return(bufPos);
}
/// <summary>
/// Parses Iso presentation accept message
/// </summary>
/// <param name="buffer">Data buffer</param>
/// <param name="offset">Index of the first message byte</param>
/// <param name="length">Length of the buffer from offset to end</param>
/// <returns>Index to the user data (payload) in the absolute numbering (from the buffer index 0)</returns>
public int parseAcceptMessage(byte[] buffer, int offset, int length)
{
int maxBufPos = offset + length;
int bufPos = offset;
byte cpTag = buffer[bufPos++];
if (cpTag != 0x31)
{
iecs.logger.LogDebug("PRES: not a CPA message\n");
return(0);
}
int len = 0;
bufPos = IsoUtil.BerDecoder_decodeLength(buffer, ref len, bufPos, maxBufPos);
while (bufPos < maxBufPos)
{
byte tag = buffer[bufPos++];
bufPos = IsoUtil.BerDecoder_decodeLength(buffer, ref len, bufPos, maxBufPos);
if (bufPos < 0)
{
iecs.logger.LogDebug("PRES: wrong parameter length\n");
return(0);
}
switch (tag)
{
case 0xa0: /* mode-selector */
bufPos += len; /* ignore content since only normal mode is allowed */
break;
case 0xa2: /* normal-mode-parameters */
bufPos = parseNormalModeParameters(buffer, len, bufPos);
if (bufPos < 0)
{
iecs.logger.LogDebug("PRES: error parsing normal-mode-parameters");
return(0);
}
break;
default:
iecs.logger.LogDebug(String.Format("PRES: CPA unknown tag {0}", tag));
bufPos += len;
break;
}
}
return(bufPos);
}
int parseNormalModeParameters(byte[] buffer, int totalLength, int bufPos)
{
int endPos = bufPos + totalLength;
while (bufPos < endPos)
{
byte tag = buffer[bufPos++];
int len = 0;
bufPos = IsoUtil.BerDecoder_decodeLength(buffer, ref len, bufPos, endPos);
if (bufPos < 0)
{
iecs.logger.LogDebug("PRES: wrong parameter length");
return(-1);
}
switch (tag)
{
case 0x81: /* calling-presentation-selector */
iecs.logger.LogDebug("PRES: calling-pres-sel");
bufPos += len;
break;
case 0x82: /* calling-presentation-selector */
iecs.logger.LogDebug("PRES: calling-pres-sel");
bufPos += len;
break;
case 0xa4: /* presentation-context-definition list */
iecs.logger.LogDebug("PRES: pcd list");
bufPos = parsePresentationContextDefinitionList(buffer, len, bufPos);
break;
case 0x61: /* user data */
iecs.logger.LogDebug("PRES: user-data");
bufPos = parseFullyEncodedData(buffer, len, bufPos);
if (bufPos < 0)
{
return(-1);
}
break;
default:
iecs.logger.LogDebug("PRES: unknown tag in normal-mode");
bufPos += len;
break;
}
}
return(bufPos);
}
public AcseIndication parseMessage(byte[] buffer, int offset, int length)
{
AcseIndication indication;
int messageSize = offset + length;
int bufPos = offset;
byte messageType = buffer[bufPos++];
int len = 0;
bufPos = IsoUtil.BerDecoder_decodeLength(buffer, ref len, bufPos, messageSize);
if (bufPos < 0)
{
iecs.logger.LogDebug("ACSE: AcseConnection_parseMessage: invalid ACSE message!");
return(AcseIndication.ACSE_ERROR);
}
switch (messageType)
{
case 0x60:
indication = parseAarqPdu(buffer, bufPos, messageSize);
break;
case 0x61:
indication = parseAarePdu(buffer, bufPos, messageSize);
break;
case 0x62: /* A_RELEASE.request RLRQ-apdu */
indication = AcseIndication.ACSE_RELEASE_REQUEST;
break;
case 0x63: /* A_RELEASE.response RLRE-apdu */
indication = AcseIndication.ACSE_RELEASE_RESPONSE;
break;
case 0x64: /* A_ABORT */
indication = AcseIndication.ACSE_ABORT;
break;
default:
iecs.logger.LogDebug("ACSE: Unknown ACSE message\n");
indication = AcseIndication.ACSE_ERROR;
break;
}
return(indication);
}
/// <summary>
/// Parses Iso presentation user data message
/// </summary>
/// <param name="buffer">Data buffer</param>
/// <param name="offset">Index of the first message byte</param>
/// <param name="length">Length of the buffer from offset to end</param>
/// <returns>Index to the user data (payload) in the absolute numbering (from the buffer index 0)</returns>
public int parseUserData(byte[] buffer, int offset, int length)
{
int bufPos = offset;
if (length < 9)
{
return(0);
}
if (buffer[bufPos++] != 0x61)
{
return(0);
}
int len = 0;
bufPos = IsoUtil.BerDecoder_decodeLength(buffer, ref len, bufPos, length);
if (buffer[bufPos++] != 0x30)
{
return(0);
}
bufPos = IsoUtil.BerDecoder_decodeLength(buffer, ref len, bufPos, length);
if (buffer[bufPos++] != 0x02)
{
return(0);
}
if (buffer[bufPos++] != 0x01)
{
return(0);
}
nextContextId = buffer[bufPos++];
if (buffer[bufPos++] != 0xa0)
{
return(0);
}
int userDataLength = 0;
bufPos = IsoUtil.BerDecoder_decodeLength(buffer, ref userDataLength, bufPos, length);
return(bufPos);
}
AcseIndication parseAarqPdu(byte[] buffer, int bufPos, int maxBufPos)
{
iecs.logger.LogDebug("ACSE: parse AARQ PDU\n");
int authValuePos = 0;
int authValueLen = 0;
int authMechanismPos = 0;
int authMechLen = 0;
bool userInfoValid = false;
while (bufPos < maxBufPos)
{
byte tag = buffer[bufPos++];
int len = 0;
bufPos = IsoUtil.BerDecoder_decodeLength(buffer, ref len, bufPos, maxBufPos);
if (bufPos < 0)
{
iecs.logger.LogDebug("ACSE: parseAarqPdu: user info invalid!\n");
return(AcseIndication.ACSE_ASSOCIATE_FAILED);
}
switch (tag)
{
case 0xa1: /* application context name */
bufPos += len;
break;
case 0xa2: /* called AP title */
bufPos += len;
break;
case 0xa3: /* called AE qualifier */
bufPos += len;
break;
case 0xa6: /* calling AP title */
bufPos += len;
break;
case 0xa7: /* calling AE qualifier */
bufPos += len;
break;
case 0x8a: /* sender ACSE requirements */
bufPos += len;
break;
case 0x8b: /* (authentication) mechanism name */
authMechLen = len;
authMechanismPos = bufPos;
bufPos += len;
break;
case 0xac: /* authentication value */
bufPos++;
bufPos = IsoUtil.BerDecoder_decodeLength(buffer, ref len, bufPos, maxBufPos);
authValueLen = len;
authValuePos = bufPos;
bufPos += len;
break;
case 0xbe: /* user information */
if (buffer[bufPos] != 0x28)
{
iecs.logger.LogDebug("ACSE: invalid user info\n");
bufPos += len;
}
else
{
bufPos++;
bufPos = IsoUtil.BerDecoder_decodeLength(buffer, ref len, bufPos, maxBufPos);
bufPos = parseUserInformation(buffer, bufPos, bufPos + len, ref userInfoValid);
}
break;
default: /* ignore unknown tag */
iecs.logger.LogDebug(String.Format("ACSE: parseAarqPdu: unknown tag 0x{0:X2}", tag));
bufPos += len;
break;
}
}
if (checkAuthentication(buffer, authMechanismPos, authMechLen, authValuePos, authValueLen) == false)
{
iecs.logger.LogDebug("ACSE: parseAarqPdu: check authentication failed!");
return(AcseIndication.ACSE_ASSOCIATE_FAILED);
}
if (userInfoValid == false)
{
iecs.logger.LogDebug("ACSE: parseAarqPdu: user info invalid!");
return(AcseIndication.ACSE_ASSOCIATE_FAILED);
}
return(AcseIndication.ACSE_ASSOCIATE);
}
AcseIndication parseAarePdu(byte[] buffer, int bufPos, int maxBufPos)
{
iecs.logger.LogDebug("ACSE: parse AARE PDU");
bool userInfoValid = false;
uint result = 99;
while (bufPos < maxBufPos)
{
byte tag = buffer[bufPos++];
int len = 0;
bufPos = IsoUtil.BerDecoder_decodeLength(buffer, ref len, bufPos, maxBufPos);
switch (tag)
{
case 0xa1: /* application context name */
bufPos += len;
break;
case 0xa2: /* result */
bufPos++;
bufPos = IsoUtil.BerDecoder_decodeLength(buffer, ref len, bufPos, maxBufPos);
result = IsoUtil.BerDecoder_decodeUint32(buffer, len, bufPos);
bufPos += len;
break;
case 0xa3: /* result source diagnostic */
bufPos += len;
break;
case 0xbe: /* user information */
if (buffer[bufPos] != 0x28)
{
iecs.logger.LogDebug("ACSE: invalid user info");
bufPos += len;
}
else
{
bufPos++;
bufPos = IsoUtil.BerDecoder_decodeLength(buffer, ref len, bufPos, maxBufPos);
bufPos = parseUserInformation(buffer, bufPos, bufPos + len, ref userInfoValid);
}
break;
default: /* ignore unknown tag */
iecs.logger.LogDebug(String.Format("ACSE: parseAarePdu: unknown tag 0x{0:X2}", tag));
bufPos += len;
break;
}
}
if (!userInfoValid)
{
return(AcseIndication.ACSE_ERROR);
}
if (result != 0)
{
return(AcseIndication.ACSE_ASSOCIATE_FAILED);
}
return(AcseIndication.ACSE_ASSOCIATE);
}
/// <summary>
/// Parses Iso presentation connect message
/// </summary>
/// <param name="buffer">Data buffer</param>
/// <param name="offset">Index of the first message byte</param>
/// <param name="length">Length of the buffer from offset to end</param>
/// <returns>Index to the user data (payload) in the absolute numbering (from the buffer index 0)</returns>
public int parseConnect(byte[] buffer, int offset, int length)
{
int maxBufPos = offset + length;
int bufPos = offset;
byte cpTag = buffer[bufPos++];
if (cpTag != 0x31)
{
iecs.logger.LogDebug("PRES: not a CP type");
return(0);
}
int len = 0;
bufPos = IsoUtil.BerDecoder_decodeLength(buffer, ref len, bufPos, maxBufPos);
iecs.logger.LogDebug(String.Format("PRES: CPType with len {0}", len));
while (bufPos < maxBufPos)
{
byte tag = buffer[bufPos++];
bufPos = IsoUtil.BerDecoder_decodeLength(buffer, ref len, bufPos, maxBufPos);
if (bufPos < 0)
{
iecs.logger.LogDebug("PRES: wrong parameter length\n");
return(0);
}
switch (tag)
{
case 0xa0: /* mode-selection */
{
if (buffer[bufPos++] != 0x80)
{
iecs.logger.LogDebug("PRES: mode-value of wrong type!");
return(0);
}
bufPos = IsoUtil.BerDecoder_decodeLength(buffer, ref len, bufPos, maxBufPos);
uint modeSelector = IsoUtil.BerDecoder_decodeUint32(buffer, len, bufPos);
iecs.logger.LogDebug(String.Format("PRES: modesel {0}", modeSelector));
bufPos += len;
}
break;
case 0xa2: /* normal-mode-parameters */
bufPos = parseNormalModeParameters(buffer, len, bufPos);
if (bufPos < 0)
{
iecs.logger.LogDebug("PRES: error parsing normal-mode-parameters");
return(0);
}
break;
default: /* unsupported element */
iecs.logger.LogDebug(String.Format("PRES: tag 0x{0:X2} not recognized\n", tag));
bufPos += len;
break;
}
}
return(bufPos);
}
int parsePCDLEntry(byte[] buffer, int totalLength, int bufPos)
{
int endPos = bufPos + totalLength;
int contextId = -1;
bool isAcse = false;
bool isMms = false;
while (bufPos < endPos)
{
byte tag = buffer[bufPos++];
int len = 0;
bufPos = IsoUtil.BerDecoder_decodeLength(buffer, ref len, bufPos, endPos);
switch (tag)
{
case 0x02: /* presentation-context-identifier */
contextId = (int)IsoUtil.BerDecoder_decodeUint32(buffer, len, bufPos);
bufPos += len;
break;
case 0x06: /* abstract-syntax-name */
iecs.logger.LogDebug(String.Format("PRES: abstract-syntax-name with len {0}", len));
if (len == 5)
{
isMms = true;
for (int i = 0; i < 5; i++)
{
if (buffer[bufPos + i] != asn_id_mms[i])
{
isMms = false;
}
}
//if (memcmp(buffer + bufPos, asn_id_mms, 5) == 0)
// isMms = true;
}
else if (len == 4)
{
isAcse = true;
for (int i = 0; i < 4; i++)
{
if (buffer[bufPos + i] != asn_id_as_acse[i])
{
isAcse = false;
}
}
//if (memcmp(buffer + bufPos, asn_id_as_acse, 4) == 0)
// isAcse = true;
}
bufPos += len;
break;
case 0x30: /* transfer-syntax-name */
iecs.logger.LogDebug("PRES: ignore transfer-syntax-name");
bufPos += len;
break;
default:
iecs.logger.LogDebug("PRES: unknown tag in presentation-context-definition-list-entry");
bufPos += len;
break;
}
}
if (contextId < 0)
{
iecs.logger.LogDebug("PRES: ContextId not defined!");
return(-1);
}
if ((isAcse == false) && (isMms == false))
{
iecs.logger.LogDebug("PRES: not an ACSE nor MMS context definition");
return(-1);
}
if (isMms)
{
mmsContextId = (byte)contextId;
iecs.logger.LogDebug(String.Format("PRES: MMS context id is {0}", contextId));
}
else
{
acseContextId = (byte)contextId;
iecs.logger.LogDebug(String.Format("PRES: ACSE context id is {0}", contextId));
}
return(bufPos);
}
int parseFullyEncodedData(byte[] buffer, int len, int bufPos)
{
int presentationSelector = -1;
bool userDataPresent = false;
int endPos = bufPos + len;
if (buffer[bufPos++] != 0x30)
{
iecs.logger.LogDebug("PRES: user-data parse error");
return(-1);
}
bufPos = IsoUtil.BerDecoder_decodeLength(buffer, ref len, bufPos, endPos);
endPos = bufPos + len;
if (bufPos < 0)
{
iecs.logger.LogDebug("PRES: wrong parameter length");
return(-1);
}
while (bufPos < endPos)
{
byte tag = buffer[bufPos++];
int length = 0;
bufPos = IsoUtil.BerDecoder_decodeLength(buffer, ref length, bufPos, endPos);
if (bufPos < 0)
{
iecs.logger.LogDebug("PRES: wrong parameter length");
return(-1);
}
switch (tag)
{
case 0x02: /* presentation-context-identifier */
iecs.logger.LogDebug("PRES: presentation-context-identifier");
{
presentationSelector = (int)IsoUtil.BerDecoder_decodeUint32(buffer, length, bufPos);
nextContextId = (byte)presentationSelector;
bufPos += length;
}
break;
case 0xa0:
iecs.logger.LogDebug("PRES: fully-encoded-data");
userDataPresent = true;
nextPayload_bufferIndex = bufPos;
nextPayload_size = length;
bufPos += length;
break;
default:
iecs.logger.LogDebug(String.Format("PRES: fed: unknown tag 0x{0:X2}", tag));
bufPos += length;
break;
}
}
if (!userDataPresent)
{
iecs.logger.LogDebug("PRES: user-data not present\n");
return(-1);
}
return(bufPos);
}
