WNT Client/Server SDK
Tony Vaccaro
CS699 Project
Presentation
Primary Objective

Develop a basic client/server
application that would
demonstrate several of the
primitive but essential
functions required to
implement robust client/server
solutions.
 Communication System:
Transport and Protocol
 Security Mechanism
 Multi-Threaded Capability
 Multi-User Operation
Project Description

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A Software Development Kit (SDK)
that could be used as a design
center for implementation of a
complete client/server based
solution.
Suitable for development of
solutions where simple remote
management of a system or
resource is required.
Applications can issue commands
and obtain system specific
information from remote hosts for
desktop management applications.
Commands and information could
include any that are supported by
the Win32 API.
Software Components
Three basic software components:

WNT Agent (server)

Installed as a service program on a
Windows NT host system and starts at
boot time. Developed in C with Visual
C++.
WNT Agent Test (client)
A Win32 console based application.
Runs on local host or remote work
stations. Developed in C with Visual
C++.

Client/Server SDK Setup
Responsible
for
installing
and
uninstalling all components. Sets-up
registry parameters. Developed with
InstallShield.
Software Engineering
Approach

Project followed a traditional
“waterfall” model of program
development. Report includes:
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
Functional section that specifies the
primary capabilities of server, client,
and setup programs.
Design section that specifies the
overall system architecture, data-flow,
and data dictionaries.
A development section that describes
the tools used to obtain software
metrics, perform integrated debugging
and to maintain source control.
A system test section that outlines the
test cases used to verify specific areas
of program functionality.
Server Functionality
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WNT service application started
automatically at system boot time.
Interfaces with a host server using Win32
function calls and with remote clients using
the Windows Sockets (WinSock) API.
Capable of servicing multiple concurrent
client connections and service requests.
Implements a security mechanism that both
identifies and authenticates clients
requesting connection.
Implements a common messaging protocol
that is used when transmitting and
receiving data with clients.
Implements an event logging facility that
facilitates troubleshooting and maintenance
activities.
Extensible, allowing the addition of new
commands and service routines.
Client Functionality



Implemented as a command line (non-GUI)
based program.
Communicates with the Agent service
program using the TCP/IP transport
protocol.
Uses the messaging protocol supported by
the Agent service when transferring data
and commands.
Command
Syntax
Return
Get Agent Information “100|ProcessId” “0|Agent_Status_Command_Success |Agent Info
(string)<EoM>\n"”


Is able to display the constructed command
syntax sent to the Agent service as well as
the resulting response data.
Is capable of establishing connection with
the Agent service through use of the
supported security mechanism.
Sending and Receiving Data
Structures
Sending
char* Hexify(char* bData, int iLength)
{
int i;
char* cHexBuf;
cHexBuf = (char*) malloc((iLength*2) + 1);
memset(cHexBuf, '\0', (iLength*2) + 1);
// Grab a new buffer
// Clear it
// Convert each “char” of binary data to two hex chars
for (i = 0; i < iLength; i++)
{
sprintf (cHexBuf + (i*2), "%02x", (UCHAR) bData[i]);
}
return cHexBuf;
}
Receiving
// cast a char pointer to the TestInfo structure
pTestInfo = (char *) &sAgentTestInfo;
// Loop till End - De-Hexify the data
while (*pHexData != '\0')
{
// Get 2 characters
memcpy(cTemp, pHexData, 2);
// Save the byte in TestInfo structure
*pTestInfo = (UCHAR) strtol(cTemp, NULL, 16);
// Bump the pointers
pHexData += 2;
pTestInfo ++;
}
Figure 3
SERVER ARCHITECTURE
Agent
WNT System Services
Win32 API
Agent
service parameters
START AGENT
SERVICE
MAIN
Service Control Manager
Starts/Stops Agent Thread
Global Data Store
System
Info
dir paths
Thread
Initialize Critical
Sections and
WaitForSingleObj
Config
Get System and
Config File Dirs
dir paths
Thread
Create Client
Comm Thread
System
Directories
Win32 API
Config
Parse Data
files
Winnt
Config
Log Event
Get System
Info
Client
Communication
Thread
Config File
Client
Communication Thread
Connect to Client
Event
Messagss
Client File
Socket
Handles
Thread
Create Process
Request Thread
Socket
Create Listen
Socket
Socket
write/read/close/
accept socket
Client
Validate
Client
Winnt
Log Errors
Args passed: client name
socket handle
PassKey (seed) and Msg
Thread
Lock Rand
Crit Section
Client
Process Request Thread
Execute Client Command
Socket
Read/Write
Socket
Client
Create
PassKey
Winnt
Log Errors
PassKey
Swapped PassKey
Misc
Endian
Little Swap
Socket
Handle
filename
Socket
Get Thread
ID
Socket
Read/Write/
Close Socket
Thread
Exit Thread
Client
Load Agent Test
Structure
ClientCmd
Hexify Data
ClientCmd
Create Beep
Thread
Revcheck
Get File
Versions
Winnt
Log Errors
Client Specified File
Figure 4
CLIENT ARCHITECTURE
AgentTest
Input Arguments;
Remote Server
and Password
MAIN
Socket Handle
and Message
Comm Code
AgenTest
AgenTest
Get Process ID
Comm string
AgenTest
Display
Commands
AgenTest
Get Command
Code
AgenTest
Build Command
Send Message
User Input
Process Info
Win32 System
Service
Commands
Display Output
Encrypted Password
Socket Handle
Socket Handle
Seed
Password
PassKey
AgenTest
AgenTest
Receive
Message
AgenTest
Close Socket
Remote IP
AgenTest
Connect to
Remote Server
AgenTest
Client Connect
Remote IP
AgenTest
Get Host by
Name
AgenTest
Encrypt
Password
Create PassKey
Socket Handle
Socket Handle
AgenTest
Create Socket
AgenTest
Bind IP and Port
to Socket
Figure 5
Monitor Metric Details – Server Program
Figure 6
Monitor Metric Details – Client Program Component
SERVER DATA-FLOW DIAGRAM
Service
Params
Start Agent
Service
SCM Thread
Dispatched
Event
Message
Event Viewer
Logs Event
Log Start
Event
Locate Client
Config files
Config
files
Directory Path
Parse Client
Security Data
ClientData
Client
name &
seed
Get System
Information
Node,
machine, &
versions
Init Critical Sections:
Socket, DB, and RandNum
Start Sockets and Create
TCP Socket Communication
Thread
Socket
Communication
Thread
Create Socket and Listen
on Port: 4988
A
Client Data
Structure
Global
Data
A
Incoming Client
Request on Port 4988
(TCP Network)
Return server socket to
listen state; ready to
accept new client
requests
Accept Socket
Socket handle
Client name and server
socket descriptor
Client Data
Structure
Validate Client
Socket handle, client name,
Seed value (for password encryption)
Invalid Client
Create Process
Request Thread
H
Process Request Thread;
Socket Handle, Client name,
and Seed value passed
Read Socket
Buffer
Close Socket if
0 Length Read
Socket
Handle
Socket Data
Destroy this
thread
Socket
Handle
Parse and Decode
Client’s Command
Command
Command Execution Routines
B
C
D
E
F
G
CLIENTCMD Module Abstract and Data Dictionary
ClientCmd includes a set of functions that perform command specific processing for client
requests received by the Agent.
Entity Name
Type
THREADPARAMS
Structure
ThreadCountInfo
Structure
Hexify
Function
BeepThread
Function
Beeper
Function
Description
(int) iThreadCount – max number of threads
PTHREADCOUNTINFO pThreadCountInfo - Pointer to
global threadcountinfo struct
(int) iThreadCount - counts active Beep threads
(BOOL) ar_bBeepStop[MAX_THREADS] – stores stop flags
Converts a buffer of binary data to ASCII Hex characters.
Inputs: Pointer to binary buffer and length of buffer.
Outputs: Pointer to ASCII Hex buffer
Prepares thread parameters and creates a worker thread
which continually beeps until a system modal MessageBox
is acknowledged.
Inputs: PTHREADCOUNTINFO, a pointer to a thread info
structure.
Outputs: Pointer to a status string to return to the client.
Runs as a worker thread and continually beeps to indicate
the existence of the thread.
Inputs: A pointer the ThreadParams structure
Outputs: None
AGENT Module Abstract and Data Dictionary
The purpose of the Agent module is to request the WNT Service Control Manager (SCM) to start
the Agent service, prepare configuration data, initialize critical sections, and launch the client
communication thread to wait for incoming service requests.
Entity Name
Type
MAIN
Function
StartAgent
Function
Description
The main routine. First called at program startup.
Inputs: argc - The number of arguments in 'argv'.
argv - a pointer to an 'array' of passed arguments.
Outputs: None
This routine starts the Agent functions
Inputs: None
Outputs: None
REVCHECK Module Abstract and Data Dictionary
The purpose of the Revcheck module is to retrieve the file version from a specified file’s
GetFileVersionInfo structure.
Entity Name
GetFileVer
Type
Function
Description
Retrieves the file version from the GetFileVersionInfo
structure.
Inputs: LPSTR strFileName - name of file
LPSTR strFileVersion - gets loaded with the
version
Outputs: Returns TRUE if a version is found
System Test Matrix
TEST CASE
DESCRIPTION
SUCCESS CRITERA*
Kit Installation and
Setup
Invoke Setup wizard to install all
components of the kit.
Kit UnInstallation
Invoke WNTInfoAgent uninstall
from Add/Remove Programs
applet.
Agent and Client
Security
100 Level
Command
Connect with Agent using proper
client authorization and
password.
Attempt to connect with Agent
using improper client
authorization and password.
Issue 100 Level Command to
Agent from Client.
101 Level
Command
Issue 101 Level Command to
Agent from Client.
102 Level
Command
Issue 102 Level Command to
Agent from Client.
103 Level
Command
104 Level
Command
Issue 103 Level Command to
Agent from Client with valid file
path and name.
Issue 103 Level Command to
Agent from Client.
900 Level
Command
Issue the 900 Level Command to
the Agent from the Client.
Agent and Client programs are
installed in user selected folders,
correct registry parameters are
entered, Agent service starts, and
Client program executes. Startup
event is logged in the event viewer
Uninstall can be invoked from
Add/Remove Programs applet. All
files and folders are removed from
target system.
Client is granted access to the
server using the correct password
and/or client name authorization.
Client is denied access without the
correct password and/or client
name authorization.
Agent returns the correct current
version of the running agent to the
client and the client outputs the
version string.
Agent returns the correct server
information to the client and the
client outputs the information string
Agent launches Beeper worker
thread on host server and presents
MessageBox.
Agent cancels worker when user
clicks OK.
Agent returns the correct file
version for the specified file and the
Client properly displays the output.
Agent returns test structure
contents to Client and Client
properly displays output.
Agent shuts-down. Shutdown event
is logged in the event viewer.
Multi-thread and
multi-user Tests
Use 16 clients to concurrently
connect with the Agent and
issue 102 Level Commands.
Agent establishes connection with
each client and launches a
corresponding beep thread for
each. Also, threads are destroyed
and connections closed when each
thread is cancelled.
PASS
X
X
X
X
X
X
X
X
X
X
FAIL
CDROM Media Layout
Visual C++ Project Files for
the Server and Client
Following Setup start agent from
START\Programs\CS699\SpAgentTest
Debug version runs as a console application,
Release version runs as an installed WNT Service
MS Word Project Proposal and Report in Docs folder
MS Power Point presentation in Presentation folder
Kit Setup Wizard. Double click on Setup.exe or use
run from START menu.
Source Code Files for all project programs. View
with any text editor or from Visual C++