SSPI Kerberos for delegation
Kasparov
ganesh.tambat at gmail.com
Thu Dec 18 11:24:13 EST 2008
Hi,
We want the authentication to happen without providing credentials
anywhere. For this we are planning to use Windows SSPI. Now the
problem I am facing is once the authentication from client to server
is successful, I want to use the
security context created in server to connect back and authenticate to
the client. I am trying to find out if this thing is possible with
SSPI.
For this I have written an application (prototype) with client side
and server side. I am connecting to the server and after successfully
authentication at the server side I try to connect back (to the server
component on the client
machine, running in the same process and thread as client) using the
same procedure I used in the client side. My understanding is since I
have impersonated I will be able to authenticate the same user again.
But I always get the error
"No credentials are available in the security package" and the
credentials might have expired. I have verified that both the user
accounts are trusted for delegation and "cannot be delegated" tab is
unchcked. Also both the servers are
trusted for delegation for any service for Kerberos.
I have tried doing this with NTLM and Kerberos. With NTLM it looks
like the reverse connection is successful but after impersonation at
the client side if I try to print the user name it says "Anonymous
Logon". With Kerberos I am
getting various errors (not enough memory, credentials are expired
etc) and I am still working on that part. The reason I am trying with
Kerberos is that I learned from some articles on Net that such a thing
(delegation) is possible only
with Kerberos.
Surprisingly I am not able to find out a single working solution of
this kind. I have pasted my entire code below. Can anyone help me on
this and advise me on how this can be achieved ? Please see the code
samples below:
Client (Logged in user: win\gtambat)
***************************************************************************************
#include <stdio.h>
#include <windows.h>
#include <string.h>
#include <malloc.h>
#define SECURITY_WIN32 1
#include <security.h>
#pragma hdrstop
//
====================================================================
// IMPORTANT NOTICE -- Check out
// http://www.mvps.org/security/sspi.html
// for the gory details of how this works
//
====================================================================
void auth( SOCKET s, CredHandle& cred, CtxtHandle& cliCtx,
const char *tokenSource, const char *name = NULL,
const char *pwd = NULL, const char *domain = NULL );
PSecurityFunctionTable pf = NULL;
void initSecLib( HINSTANCE& hSec );
bool Ganesh_auth( SOCKET s, CredHandle& cred, CtxtHandle& srvCtx )
{
int rc;
bool haveToken = true;
SecPkgInfo *secPackInfo;
int bytesReceived = 0, bytesSent = 0;
char buf[256];
DWORD bufsiz = sizeof buf;
HANDLE threadRet;
puts( "auth() entered" );
rc = (pf->QuerySecurityPackageInfo)( "Kerberos", &secPackInfo );
printf( "QSPI(): %08xh\n", rc );
if ( rc != SEC_E_OK )
haveToken = false;
TimeStamp useBefore;
rc = (pf->AcquireCredentialsHandle)( NULL, "Kerberos",
SECPKG_CRED_BOTH,
NULL, NULL, NULL, NULL, &cred, &useBefore );
rc = GetLastError();
printf( "ACH(): %08xh\n", rc );
if ( rc != SEC_E_OK )
haveToken = false;
// input and output buffers
SecBufferDesc obd, ibd;
SecBuffer ob, ib;
DWORD ctxAttr;
bool haveContext = false;
while ( 1 )
{
// prepare to get the server's response
ibd.ulVersion = SECBUFFER_VERSION;
ibd.cBuffers = 1;
ibd.pBuffers = &ib; // just one buffer
ib.BufferType = SECBUFFER_TOKEN; // preping a token here
// receive the client's POD
// MACHINE-DEPENDENT CODE! (Besides, we assume that we
// get the length with a single read, which is not guaranteed)
recv( s, (char *) &ib.cbBuffer, sizeof ib.cbBuffer, 0 );
bytesReceived += sizeof ib.cbBuffer;
ib.pvBuffer = LocalAlloc( 0, ib.cbBuffer );
char *p = (char *) ib.pvBuffer;
int n = ib.cbBuffer;
while ( n )
{
rc = recv( s, p, n, 0 );
// if ( rc == SOCKET_ERROR )
// wserr( rc, "recv" );
// if ( rc == 0 )
// wserr( 999, "recv" );
bytesReceived += rc;
n -= rc;
p += rc;
}
// by now we have an input buffer
obd.ulVersion = SECBUFFER_VERSION;
obd.cBuffers = 1;
obd.pBuffers = &ob; // just one buffer
ob.BufferType = SECBUFFER_TOKEN; // preping a token here
ob.cbBuffer = secPackInfo->cbMaxToken;
ob.pvBuffer = LocalAlloc( 0, ob.cbBuffer );
// rc = (pf->AcceptSecurityContext)( &cred, haveContext? &srvCtx:
NULL,
// &ibd, 0, SECURITY_NATIVE_DREP, &srvCtx, &obd, &ctxAttr,
// &useBefore );
rc = (pf->AcceptSecurityContext)( &cred, haveContext? &srvCtx: NULL,
&ibd, 0, SECURITY_NATIVE_DREP /*SECURITY_NETWORK_DREP*/, &srvCtx,
&obd, &ctxAttr,
&useBefore );
printf( "ASC(): %08xh\n", rc );
if ( ib.pvBuffer != NULL )
{
LocalFree( ib.pvBuffer );
ib.pvBuffer = NULL;
}
if ( rc == SEC_I_COMPLETE_AND_CONTINUE || rc ==
SEC_I_COMPLETE_NEEDED )
{
if ( pf->CompleteAuthToken != NULL ) // only if implemented
(pf->CompleteAuthToken)( &srvCtx, &obd );
if ( rc == SEC_I_COMPLETE_NEEDED )
rc = SEC_E_OK;
else if ( rc == SEC_I_COMPLETE_AND_CONTINUE )
rc = SEC_I_CONTINUE_NEEDED;
}
// send the output buffer off to the server
// warning -- this is machine-dependent! FIX IT!
if ( rc == SEC_E_OK || rc == SEC_I_CONTINUE_NEEDED )
{
if ( ob.cbBuffer != 0 )
{
send( s, (const char *) &ob.cbBuffer, sizeof ob.cbBuffer, 0 );
bytesSent += sizeof ob.cbBuffer;
send( s, (const char *) ob.pvBuffer, ob.cbBuffer, 0 );
bytesSent += ob.cbBuffer;
}
LocalFree( ob.pvBuffer );
ob.pvBuffer = NULL;
}
if ( rc != SEC_I_CONTINUE_NEEDED )
break;
haveContext = true;
// loop back for another round
puts( "looping" );
}
// we arrive here as soon as InitializeSecurityContext()
// returns != SEC_I_CONTINUE_NEEDED.
if ( rc != SEC_E_OK )
{
printf( "Oops! ASC() returned %08xh!\n", rc );
haveToken = false;
}
rc = GetLastError();
GetUserName( buf, &bufsiz );
// now we try to use the context
rc = (pf->ImpersonateSecurityContext)( &srvCtx );
printf( "ImpSC(): %08xh\n", rc );
if ( rc != SEC_E_OK )
{
printf( "Oops! ImpSC() returns %08xh!\n", rc );
haveToken = false;
}
else
{
char buf[256];
DWORD bufsiz = sizeof buf;
GetUserName( buf, &bufsiz );
printf( "user name: \"%s\"\n", buf );
(pf->RevertSecurityContext)( &srvCtx );
printf( "RSC(): %08xh\n", rc );
}
(pf->FreeContextBuffer)( secPackInfo );
printf( "auth() exiting (%d received, %d sent)\n", bytesReceived,
bytesSent );
return haveToken;
}
int Ganesh_Server_Impl()
{
int rc, port = 12000, addrlen;
bool haveToken;
SOCKET sock, s;
WSADATA wsadata;
PSERVENT pse;
SOCKADDR_IN addr;
HINSTANCE hSecLib;
initSecLib( hSecLib );
rc = WSAStartup( 2, &wsadata );
// wserr( rc, "WSAStartup" );
sock = socket( AF_INET, SOCK_STREAM, 0 );
if ( sock == INVALID_SOCKET )
{
rc = -1;
}
else
{
rc = 0;
}
// wserr( 999, "socket" );
addr.sin_family = AF_INET;
addr.sin_addr.s_addr = INADDR_ANY;
// try numeric protocol first
if ( port > 0 && port < 32768 )
addr.sin_port = htons( (short) port );
else
{
}
rc = bind( sock, (SOCKADDR *) &addr, sizeof addr );
// wserr( rc, "bind" );
rc = listen( sock, 2 );
// wserr( rc, "listen" );
CredHandle cred;
CtxtHandle srvCtx;
while ( 1 )
{
addrlen = sizeof addr;
s = accept( sock, (SOCKADDR *) &addr, &addrlen );
if ( s == INVALID_SOCKET )
{
rc = -1;
}
else
{
rc = 0;
}
// wserr( s, "accept" );
haveToken = Ganesh_auth( s, cred, srvCtx );
// now we talk to the client
printf( "haveToken = %s\n\n", haveToken? "true": "false" );
send( s, (const char *) &haveToken, sizeof haveToken, 0 );
// clean up
(pf->DeleteSecurityContext)( &srvCtx );
(pf->FreeCredentialHandle)( &cred );
closesocket( s );
}
}
// wserr() displays winsock errors and aborts. No grace there.
void wserr( int rc, const char * const funcname )
{
if ( rc == 0 )
return;
fprintf( stderr, "\nWinsock error %d [gle %d] returned by %s().\n"
"Sorry, no bonus!\n", rc, WSAGetLastError(), funcname );
WSACleanup();
exit( rc );
}
void auth( SOCKET s, CredHandle& cred, CtxtHandle& cliCtx,
const char *tokenSource, const char *name /* = NULL */,
const char *pwd /* = NULL */, const char *domain /* = NULL */ )
{
int rc, rcISC;
SecPkgInfo *secPackInfo;
SEC_WINNT_AUTH_IDENTITY *nameAndPwd = NULL;
int bytesReceived = 0, bytesSent = 0;
puts( "auth() entered" );
// the arguments to ISC() is not const ... for once, I decided
// on creating writable copies instead of using a brutalizing cast.
char *myTokenSource;
myTokenSource = _strdup( tokenSource );
if ( name != NULL )
{
nameAndPwd = (SEC_WINNT_AUTH_IDENTITY *) malloc( sizeof
SEC_WINNT_AUTH_IDENTITY );
memset( nameAndPwd, '\0', sizeof *nameAndPwd );
nameAndPwd->Domain = (byte *) _strdup( domain? domain: "" );
nameAndPwd->DomainLength = domain? strlen( domain ): 0;
nameAndPwd->User = (byte *) _strdup( name? name: "" );
nameAndPwd->UserLength = name? strlen( name ): 0;
nameAndPwd->Password = (byte *) _strdup( pwd? pwd: "" );
nameAndPwd->PasswordLength = pwd? strlen( pwd ): 0;
nameAndPwd->Flags = SEC_WINNT_AUTH_IDENTITY_ANSI;
}
rc = (pf->QuerySecurityPackageInfo)( "Kerberos", &secPackInfo );
printf( "QSPI(): %08xh\n", rc );
TimeStamp useBefore;
rc = (pf->AcquireCredentialsHandle)( NULL, "Kerberos",
SECPKG_CRED_BOTH,
NULL, nameAndPwd, NULL, NULL, &cred, &useBefore );
printf( "ACH(): %08xh\n", rc );
// input and output buffers
SecBufferDesc obd, ibd;
SecBuffer ob, ib;
DWORD ctxReq, ctxAttr;
// from sspi.h:
// #define ISC_REQ_DELEGATE 0x00000001
// #define ISC_REQ_MUTUAL_AUTH 0x00000002
// #define ISC_REQ_REPLAY_DETECT 0x00000004
// #define ISC_REQ_SEQUENCE_DETECT 0x00000008
// #define ISC_REQ_CONFIDENTIALITY 0x00000010
// #define ISC_REQ_USE_SESSION_KEY 0x00000020
// #define ISC_REQ_PROMPT_FOR_CREDS 0x00000040
// #define ISC_REQ_USE_SUPPLIED_CREDS 0x00000080
// #define ISC_REQ_ALLOCATE_MEMORY 0x00000100
// #define ISC_REQ_USE_DCE_STYLE 0x00000200
// #define ISC_REQ_DATAGRAM 0x00000400
// #define ISC_REQ_CONNECTION 0x00000800
// #define ISC_REQ_CALL_LEVEL 0x00001000
// #define ISC_REQ_EXTENDED_ERROR 0x00004000
// #define ISC_REQ_STREAM 0x00008000
// #define ISC_REQ_INTEGRITY 0x00010000
ctxReq = ISC_REQ_REPLAY_DETECT | ISC_REQ_SEQUENCE_DETECT |
ISC_REQ_CONFIDENTIALITY | ISC_REQ_DELEGATE;
bool haveInbuffer = false;
bool haveContext = false;
ib.pvBuffer = NULL;
while ( 1 )
{
obd.ulVersion = SECBUFFER_VERSION;
obd.cBuffers = 1;
obd.pBuffers = &ob; // just one buffer
ob.BufferType = SECBUFFER_TOKEN; // preping a token here
ob.cbBuffer = secPackInfo->cbMaxToken;
ob.pvBuffer = LocalAlloc( 0, ob.cbBuffer );
rcISC = (pf->InitializeSecurityContext)( &cred, haveContext?
&cliCtx: NULL,
myTokenSource, ctxReq, 0, SECURITY_NATIVE_DREP /
*SECURITY_NETWORK_DREP*/, haveInbuffer? &ibd: NULL,
0, &cliCtx, &obd, &ctxAttr, &useBefore );
printf( "ISC(): %08xh\n", rcISC );
if ( ib.pvBuffer != NULL )
{
LocalFree( ib.pvBuffer );
ib.pvBuffer = NULL;
}
if ( rcISC == SEC_I_COMPLETE_AND_CONTINUE || rcISC ==
SEC_I_COMPLETE_NEEDED )
{
if ( pf->CompleteAuthToken != NULL ) // only if implemented
(pf->CompleteAuthToken)( &cliCtx, &obd );
if ( rcISC == SEC_I_COMPLETE_NEEDED )
rcISC = SEC_E_OK;
else if ( rcISC == SEC_I_COMPLETE_AND_CONTINUE )
rcISC = SEC_I_CONTINUE_NEEDED;
}
// send the output buffer off to the server
// warning -- this is machine-dependent! FIX IT!
if ( ob.cbBuffer != 0 )
{
send( s, (const char *) &ob.cbBuffer, sizeof ob.cbBuffer, 0 );
bytesSent += sizeof ob.cbBuffer;
send( s, (const char *) ob.pvBuffer, ob.cbBuffer, 0 );
bytesSent += ob.cbBuffer;
}
LocalFree( ob.pvBuffer );
ob.pvBuffer = NULL;
if ( rcISC != SEC_I_CONTINUE_NEEDED )
break;
// prepare to get the server's response
ibd.ulVersion = SECBUFFER_VERSION;
ibd.cBuffers = 1;
ibd.pBuffers = &ib; // just one buffer
ib.BufferType = SECBUFFER_TOKEN; // preping a token here
// receive the server's response
// MACHINE-DEPENDENT CODE! (Besides, we assume that we
// get the length with a single read, which is not guaranteed)
recv( s, (char *) &ib.cbBuffer, sizeof ib.cbBuffer, 0 );
bytesReceived += sizeof ib.cbBuffer;
ib.pvBuffer = LocalAlloc( 0, ib.cbBuffer );
char *p = (char *) ib.pvBuffer;
int n = ib.cbBuffer;
while ( n )
{
rc = recv( s, p, n, 0 );
if ( rc == SOCKET_ERROR )
wserr( rc, "recv" );
if ( rc == 0 )
wserr( 999, "recv" );
bytesReceived += rc;
n -= rc;
p += rc;
}
// by now we have an input buffer and a client context
haveInbuffer = true;
haveContext = true;
// loop back for another round
puts( "looping" );
}
// we arrive here as soon as InitializeSecurityContext()
// returns != SEC_I_CONTINUE_NEEDED.
if ( rcISC != SEC_E_OK )
printf( "Oops! ISC() returned %08xh!\n", rcISC );
(pf->FreeContextBuffer)( secPackInfo );
printf( "auth() exiting (%d sent, %d received)\n", bytesSent,
bytesReceived );
free( myTokenSource );
if ( nameAndPwd != 0 )
{
if ( nameAndPwd->Domain != 0 )
free( nameAndPwd->Domain );
if ( nameAndPwd->User != 0 )
free( nameAndPwd->User );
if ( nameAndPwd->Password != 0 )
free( nameAndPwd->Password );
free( nameAndPwd );
}
}
void initSecLib( HINSTANCE& hSec )
{
PSecurityFunctionTable (*pSFT)( void );
hSec = LoadLibrary( "security.dll" );
pSFT = (PSecurityFunctionTable (*)( void )) GetProcAddress( hSec,
"InitSecurityInterfaceA" );
if ( pSFT == NULL )
{
puts( "security.dll load messed up ..." );
exit( 1 );
}
pf = pSFT();
if ( pf == NULL )
{
puts( "no function table?!?" );
exit( 1 );
}
}
int main( int argc, char *argv[] )
{
int rc, port, i, errors;
HINSTANCE hSecLib;
unsigned long naddr;
SOCKET sock;
WSADATA wsadata;
PHOSTENT phe;
PSERVENT pse;
SOCKADDR_IN addr;
//const char *tokenSource = "Authsamp", *server = "server-machine";
const char *tokenSource = "win\\gtambat1", *server = "server-
machine";
const char *portstr = "11000", *user = 0, *pwd = 0, *domain = 0;
errors = 0;
for ( i = 1; i < argc; ++ i )
{
if ( argv[i][0] != '-' && argv[i][0] != '/' )
{
printf( "\"%s\" is not a valid switch.\n", argv[i] );
++ errors;
continue;
}
switch ( argv[i][1] )
{
case 's':
if ( i >= argc - 1 )
{
printf( "\"%s\" requires an argument.\n", argv[i] );
++ errors;
}
else if ( server != 0 )
{
printf( "\"%s\" has already been used.\n", argv[i ++] );
++ errors;
}
else
server = argv[++ i];
break;
case 'p':
if ( i >= argc - 1 )
{
printf( "\"%s\" requires an argument.\n", argv[i] );
++ errors;
}
else if ( portstr != 0 )
{
printf( "\"%s\" has already been used.\n", argv[i ++] );
++ errors;
}
else
portstr = argv[++ i];
break;
case 't':
if ( i >= argc - 1 )
{
printf( "\"%s\" requires an argument.\n", argv[i] );
++ errors;
}
else if ( tokenSource != 0 )
{
printf( "\"%s\" has already been used.\n", argv[i ++] );
++ errors;
}
else
tokenSource = argv[++ i];
break;
case 'd':
if ( i >= argc - 1 )
{
printf( "\"%s\" requires an argument.\n", argv[i] );
++ errors;
}
else if ( domain != 0 )
{
printf( "\"%s\" has already been used.\n", argv[i ++] );
++ errors;
}
else
domain = argv[++ i];
break;
case 'u':
if ( i >= argc - 2 )
{
printf( "\"%s\" requires two arguments.\n", argv[i ++] );
++ errors;
}
else if ( user != 0 )
{
printf( "\"%s\" has already been used.\n", argv[i] );
i += 2;
++ errors;
}
else
{
user = argv[++ i];
pwd = argv[++ i];
}
break;
default:
printf( "\"%s\" is not a valid switch.\n", argv[i] );
++ errors;
break;
}
}
if ( server == 0 )
{
puts( "A server name or IP address must be specified." );
++ errors;
}
if ( portstr == 0 )
{
puts( "A port name or port number must be specified." );
++ errors;
}
if ( user == 0 && domain != 0 )
puts( "No user name was specified, ignoring the domain." );
if ( errors )
{
puts( "\nusage: client -s your.server.com -p serverport" );
puts( " [-t token-source] [-u user pwd [-d domain]]" );
puts( "token-source is _required_ for Kerberos and should be
your" );
puts( "current logon name (e.g., \"MYDOMAIN\\felixk\")." );
puts( "If -u is absent, your current credentials will be used." );
return 1;
}
initSecLib( hSecLib );
rc = WSAStartup( 2, &wsadata );
wserr( rc, "WSAStartup" );
sock = socket( AF_INET, SOCK_STREAM, 0 );
if ( sock == INVALID_SOCKET )
wserr( 999, "socket" );
addr.sin_family = AF_INET;
// try numeric IP address first (inet_addr)
naddr = inet_addr( server );
if ( naddr != INADDR_NONE )
{
addr.sin_addr.s_addr = naddr;
}
else
{
phe = gethostbyname( server );
if ( phe == NULL )
wserr( 1, "gethostbyname" );
addr.sin_addr.s_addr = *( (unsigned long *) (phe->h_addr) );
memcpy( (char *) &addr.sin_addr, phe->h_addr, phe->h_length );
}
// try numeric protocol first
port = atoi( portstr );
if ( port > 0 && port < 32768 )
addr.sin_port = htons( (short) port );
else
{
pse = getservbyname( portstr, "tcp" );
if ( pse == NULL )
wserr( 1, "getservbyname" );
addr.sin_port = pse->s_port;
}
CredHandle cred;
CtxtHandle cliCtx;
rc = connect( sock, (SOCKADDR *) &addr, sizeof addr );
wserr( rc, "connect" );
struct sockaddr name;
int namelen = sizeof name;;
rc = getsockname( sock, &name, &namelen );
wserr( rc, "getsockname()" );
printf( "I am %u.%u.%u.%u\n", (unsigned int) (unsigned char)
name.sa_data[2],
(unsigned int) (unsigned char) name.sa_data[3], (unsigned int)
(unsigned char) name.sa_data[4],
(unsigned int) (unsigned char) name.sa_data[5] );
auth( sock, cred, cliCtx, tokenSource, user, pwd, server ); // this
does the real work
// Added by Ganesh
//auth( sock, cred, cliCtx, tokenSource, "ganesh", "ganesh", "client-
machine" ); // this does the real work
// use the authenticated connection here
bool haveToken = false;
rc = recv( sock, (char *) &haveToken, sizeof haveToken, 0 );
if ( rc != sizeof haveToken )
wserr( 999, "result-recv" );
if ( haveToken )
puts( "That seems to have worked." );
else
puts( "Oops! Wrong user name or password?" );
// the server is probably impersonating us by now
// this is where the client and server talk business
// clean up
(pf->DeleteSecurityContext)( &cliCtx );
(pf->FreeCredentialHandle)( &cred );
rc = closesocket( sock );
wserr( rc, "closesocket" );
rc = WSACleanup();
wserr( rc, "WSACleanup" );
int j;
puts("/n/n Should I start server implemenation within client ?: ");
scanf("%d",&j);
rc = Ganesh_Server_Impl();
__try
{
FreeLibrary( hSecLib );
}
__except ( 1 )
{
puts( "Freelibrary( security.dll ) caused an access violation.
Yuck." );
}
return 0;
}
***************************************************************************************
Server (Logged in user win\gtambat1)
***************************************************************************************
#include <stdio.h>
#include <windows.h>
#include <string.h>
#include <malloc.h>
#define SECURITY_WIN32 1
#include <sspi.h>
//#include <issperr.h> // uncomment if you have an old Platform SDK
#pragma hdrstop
//
====================================================================
// IMPORTANT NOTICE -- Check out
// http://www.mvps.org/security/sspi.html
// for the gory details of how this works
//
====================================================================
PSecurityFunctionTable pf = NULL;
int Ganesh_Client_Impl(CtxtHandle &srvCtx);
void initSecLib( HINSTANCE& hSec );
void Ganesh_auth( SOCKET s, CredHandle& cred, CtxtHandle& cliCtx,
const char *tokenSource, const char *name /* = NULL */,
const char *pwd /* = NULL */, const char *domain /* = NULL */ );
void Ganesh_auth( SOCKET s, CredHandle& cred, CtxtHandle& cliCtx,
const char *tokenSource, const char *name /* = NULL */,
const char *pwd /* = NULL */, const char *domain /* = NULL */ )
{
int rc, rcISC;
SecPkgInfo *secPackInfo;
SEC_WINNT_AUTH_IDENTITY *nameAndPwd = NULL;
int bytesReceived = 0, bytesSent = 0;
//puts( "auth() entered" );
// the arguments to ISC() is not const ... for once, I decided
// on creating writable copies instead of using a brutalizing cast.
char *myTokenSource;
myTokenSource = _strdup( tokenSource );
if ( name != NULL )
{
nameAndPwd = (SEC_WINNT_AUTH_IDENTITY *) malloc( sizeof
SEC_WINNT_AUTH_IDENTITY );
memset( nameAndPwd, '\0', sizeof *nameAndPwd );
nameAndPwd->Domain = (byte *) _strdup( domain? domain: "" );
nameAndPwd->DomainLength = domain? strlen( domain ): 0;
nameAndPwd->User = (byte *) _strdup( name? name: "" );
nameAndPwd->UserLength = name? strlen( name ): 0;
nameAndPwd->Password = (byte *) _strdup( pwd? pwd: "" );
nameAndPwd->PasswordLength = pwd? strlen( pwd ): 0;
nameAndPwd->Flags = SEC_WINNT_AUTH_IDENTITY_ANSI;
}
rc = (pf->QuerySecurityPackageInfo)( "kerberos", &secPackInfo );
//printf( "QSPI(): %08xh\n", rc );
TimeStamp useBefore;
rc = GetLastError();
rc = (pf->AcquireCredentialsHandle)( NULL, "kerberos",
SECPKG_CRED_BOTH,
NULL, nameAndPwd, NULL, NULL, &cred, &useBefore );
//printf( "ACH(): %08xh\n", rc );
rc = GetLastError();
// input and output buffers
SecBufferDesc obd, ibd;
SecBuffer ob, ib;
DWORD ctxReq, ctxAttr;
// from sspi.h:
// #define ISC_REQ_DELEGATE 0x00000001
// #define ISC_REQ_MUTUAL_AUTH 0x00000002
// #define ISC_REQ_REPLAY_DETECT 0x00000004
// #define ISC_REQ_SEQUENCE_DETECT 0x00000008
// #define ISC_REQ_CONFIDENTIALITY 0x00000010
// #define ISC_REQ_USE_SESSION_KEY 0x00000020
// #define ISC_REQ_PROMPT_FOR_CREDS 0x00000040
// #define ISC_REQ_USE_SUPPLIED_CREDS 0x00000080
// #define ISC_REQ_ALLOCATE_MEMORY 0x00000100
// #define ISC_REQ_USE_DCE_STYLE 0x00000200
// #define ISC_REQ_DATAGRAM 0x00000400
// #define ISC_REQ_CONNECTION 0x00000800
// #define ISC_REQ_CALL_LEVEL 0x00001000
// #define ISC_REQ_EXTENDED_ERROR 0x00004000
// #define ISC_REQ_STREAM 0x00008000
// #define ISC_REQ_INTEGRITY 0x00010000
ctxReq = ISC_REQ_REPLAY_DETECT | ISC_REQ_SEQUENCE_DETECT |
ISC_REQ_CONFIDENTIALITY | ISC_REQ_DELEGATE;
bool haveInbuffer = false;
bool haveContext = false;
ib.pvBuffer = NULL;
while ( 1 )
{
obd.ulVersion = SECBUFFER_VERSION;
obd.cBuffers = 1;
obd.pBuffers = &ob; // just one buffer
ob.BufferType = SECBUFFER_TOKEN; // preping a token here
ob.cbBuffer = secPackInfo->cbMaxToken;
ob.pvBuffer = LocalAlloc( 0, ob.cbBuffer );
rcISC = (pf->InitializeSecurityContext)( &cred, haveContext?
&cliCtx: NULL,
myTokenSource, ctxReq, 0, SECURITY_NATIVE_DREP /
*SECURITY_NETWORK_DREP*/, haveInbuffer? &ibd: NULL,
0, &cliCtx, &obd, &ctxAttr, &useBefore );
// printf( "ISC(): %08xh\n", rcISC );
if ( ib.pvBuffer != NULL )
{
LocalFree( ib.pvBuffer );
ib.pvBuffer = NULL;
}
if ( rcISC == SEC_I_COMPLETE_AND_CONTINUE || rcISC ==
SEC_I_COMPLETE_NEEDED )
{
if ( pf->CompleteAuthToken != NULL ) // only if implemented
(pf->CompleteAuthToken)( &cliCtx, &obd );
if ( rcISC == SEC_I_COMPLETE_NEEDED )
rcISC = SEC_E_OK;
else if ( rcISC == SEC_I_COMPLETE_AND_CONTINUE )
rcISC = SEC_I_CONTINUE_NEEDED;
}
// send the output buffer off to the server
// warning -- this is machine-dependent! FIX IT!
if ( ob.cbBuffer != 0 )
{
send( s, (const char *) &ob.cbBuffer, sizeof ob.cbBuffer, 0 );
bytesSent += sizeof ob.cbBuffer;
send( s, (const char *) ob.pvBuffer, ob.cbBuffer, 0 );
bytesSent += ob.cbBuffer;
}
LocalFree( ob.pvBuffer );
ob.pvBuffer = NULL;
if ( rcISC != SEC_I_CONTINUE_NEEDED )
break;
// prepare to get the server's response
ibd.ulVersion = SECBUFFER_VERSION;
ibd.cBuffers = 1;
ibd.pBuffers = &ib; // just one buffer
ib.BufferType = SECBUFFER_TOKEN; // preping a token here
// receive the server's response
// MACHINE-DEPENDENT CODE! (Besides, we assume that we
// get the length with a single read, which is not guaranteed)
rc = recv( s, (char *) &ib.cbBuffer, sizeof ib.cbBuffer, 0 );
bytesReceived += sizeof ib.cbBuffer;
ib.pvBuffer = LocalAlloc( 0, ib.cbBuffer );
char *p = (char *) ib.pvBuffer;
int n = ib.cbBuffer;
while ( n )
{
rc = recv( s, p, n, 0 );
// if ( rc == SOCKET_ERROR )
// wserr( rc, "recv" );
// if ( rc == 0 )
// wserr( 999, "recv" );
bytesReceived += rc;
n -= rc;
p += rc;
}
// by now we have an input buffer and a client context
haveInbuffer = true;
haveContext = true;
// loop back for another round
// puts( "looping" );
}
// we arrive here as soon as InitializeSecurityContext()
// returns != SEC_I_CONTINUE_NEEDED.
if ( rcISC != SEC_E_OK )
{
printf( "Oops! ISC() returned %08xh!\n", rcISC );
}
(pf->FreeContextBuffer)( secPackInfo );
//printf( "auth() exiting (%d sent, %d received)\n", bytesSent,
bytesReceived );
free( myTokenSource );
if ( nameAndPwd != 0 )
{
if ( nameAndPwd->Domain != 0 )
free( nameAndPwd->Domain );
if ( nameAndPwd->User != 0 )
free( nameAndPwd->User );
if ( nameAndPwd->Password != 0 )
free( nameAndPwd->Password );
free( nameAndPwd );
}
}
// wserr() displays winsock errors and aborts. No grace there.
void wserr( int rc, const char * const funcname )
{
if ( rc == 0 )
return;
fprintf( stderr, "\nWinsock error %d [gle %d] returned by %s().\n"
"Sorry, no bonus!\n", rc, WSAGetLastError(), funcname );
WSACleanup();
exit( rc );
}
bool auth( SOCKET s, CredHandle& cred, CtxtHandle& srvCtx )
{
int rc;
bool haveToken = true;
SecPkgInfo *secPackInfo;
int bytesReceived = 0, bytesSent = 0;
char buf[256];
DWORD bufsiz = sizeof buf;
puts( "auth() entered" );
rc = (pf->QuerySecurityPackageInfo)( "kerberos", &secPackInfo );
printf( "QSPI(): %08xh\n", rc );
if ( rc != SEC_E_OK )
haveToken = false;
TimeStamp useBefore;
rc = (pf->AcquireCredentialsHandle)( NULL, "kerberos",
SECPKG_CRED_BOTH,
NULL, NULL, NULL, NULL, &cred, &useBefore );
// rc = (pf->AcquireCredentialsHandle)( NULL, "kerberos",
SECPKG_CRED_BOTH,
// NULL, NULL, NULL, NULL, &cred, &useBefore );
printf( "ACH(): %08xh\n", rc );
if ( rc != SEC_E_OK )
haveToken = false;
// input and output buffers
SecBufferDesc obd, ibd;
SecBuffer ob, ib;
DWORD ctxAttr;
bool haveContext = false;
while ( 1 )
{
// prepare to get the server's response
ibd.ulVersion = SECBUFFER_VERSION;
ibd.cBuffers = 1;
ibd.pBuffers = &ib; // just one buffer
ib.BufferType = SECBUFFER_TOKEN; // preping a token here
// receive the client's POD
// MACHINE-DEPENDENT CODE! (Besides, we assume that we
// get the length with a single read, which is not guaranteed)
recv( s, (char *) &ib.cbBuffer, sizeof ib.cbBuffer, 0 );
bytesReceived += sizeof ib.cbBuffer;
ib.pvBuffer = LocalAlloc( 0, ib.cbBuffer );
char *p = (char *) ib.pvBuffer;
int n = ib.cbBuffer;
while ( n )
{
rc = recv( s, p, n, 0 );
if ( rc == SOCKET_ERROR )
wserr( rc, "recv" );
if ( rc == 0 )
wserr( 999, "recv" );
bytesReceived += rc;
n -= rc;
p += rc;
}
// by now we have an input buffer
obd.ulVersion = SECBUFFER_VERSION;
obd.cBuffers = 1;
obd.pBuffers = &ob; // just one buffer
ob.BufferType = SECBUFFER_TOKEN; // preping a token here
ob.cbBuffer = secPackInfo->cbMaxToken;
ob.pvBuffer = LocalAlloc( 0, ob.cbBuffer );
rc = (pf->AcceptSecurityContext)( &cred, haveContext? &srvCtx: NULL,
&ibd, 0,/* SECURITY_NATIVE_DREP */ SECURITY_NATIVE_DREP /
*SECURITY_NETWORK_DREP*/, &srvCtx, &obd, &ctxAttr,
&useBefore );
printf( "ASC(): %08xh\n", rc );
if ( ib.pvBuffer != NULL )
{
LocalFree( ib.pvBuffer );
ib.pvBuffer = NULL;
}
if ( rc == SEC_I_COMPLETE_AND_CONTINUE || rc ==
SEC_I_COMPLETE_NEEDED )
{
if ( pf->CompleteAuthToken != NULL ) // only if implemented
(pf->CompleteAuthToken)( &srvCtx, &obd );
if ( rc == SEC_I_COMPLETE_NEEDED )
rc = SEC_E_OK;
else if ( rc == SEC_I_COMPLETE_AND_CONTINUE )
rc = SEC_I_CONTINUE_NEEDED;
}
// send the output buffer off to the server
// warning -- this is machine-dependent! FIX IT!
if ( rc == SEC_E_OK || rc == SEC_I_CONTINUE_NEEDED )
{
if ( ob.cbBuffer != 0 )
{
send( s, (const char *) &ob.cbBuffer, sizeof ob.cbBuffer, 0 );
bytesSent += sizeof ob.cbBuffer;
send( s, (const char *) ob.pvBuffer, ob.cbBuffer, 0 );
bytesSent += ob.cbBuffer;
}
LocalFree( ob.pvBuffer );
ob.pvBuffer = NULL;
}
if ( rc != SEC_I_CONTINUE_NEEDED )
break;
haveContext = true;
// loop back for another round
puts( "looping" );
}
// we arrive here as soon as InitializeSecurityContext()
// returns != SEC_I_CONTINUE_NEEDED.
if ( rc != SEC_E_OK )
{
printf( "Oops! ASC() returned %08xh!\n", rc );
haveToken = false;
}
GetUserName( buf, &bufsiz );
// now we try to use the context
rc = (pf->ImpersonateSecurityContext)( &srvCtx );
printf( "ImpSC(): %08xh\n", rc );
if ( rc != SEC_E_OK )
{
printf( "Oops! ImpSC() returns %08xh!\n", rc );
haveToken = false;
}
else
{
char buf[256];
DWORD bufsiz = sizeof buf;
printf( "haveToken = %s\n\n", haveToken? "true": "false" );
send( s, (const char *) &haveToken, sizeof haveToken, 0 );
GetUserName( buf, &bufsiz );
printf( "user name: \"%s\"\n", buf );
//(pf->RevertSecurityContext)( &srvCtx );
printf( "RSC(): %08xh\n", rc );
}
//(pf->FreeContextBuffer)( secPackInfo );
printf( "auth() exiting (%d received, %d sent)\n", bytesReceived,
bytesSent );
return haveToken;
}
int Ganesh_Client_Impl(CtxtHandle &srvCtx)
{
char buf[256];
DWORD bufsiz = sizeof buf;
int rc = 0;
//CtxtHandle tmpCtx = srvCtx;
SecPkgContext_Lifespan lspan;
rc = (pf->QueryContextAttributes)(&srvCtx, SECPKG_ATTR_LIFESPAN,
&lspan);
rc = GetLastError();
GetUserName( buf, &bufsiz );
//rc = (pf->ImpersonateSecurityContext)( &srvCtx );
rc = GetLastError();
GetUserName( buf, &bufsiz );
int port, i, errors;
unsigned long naddr;
SOCKET sock;
WSADATA wsadata;
PHOSTENT phe;
PSERVENT pse;
SOCKADDR_IN addr;
HINSTANCE hSecLib;
const char *tokenSource = "win\\gtambat", *server = "client-machine";
//const char *tokenSource = "PUN\\gtambat"/*"Authsamp"*/, *server =
"client-machine";
const char *portstr = "12000", *user = 0, *pwd = 0, *domain = 0;
errors = 0;
if ( server == 0 )
{
//puts( "A server name or IP address must be specified." );
++ errors;
}
if ( portstr == 0 )
{
//puts( "A port name or port number must be specified." );
++ errors;
}
if ( user == 0 && domain != 0 )
{
}
// puts( "No user name was specified, ignoring the domain." );
if ( errors )
{
/* puts( "\nusage: client -s your.server.com -p serverport" );
puts( " [-t token-source] [-u user pwd [-d domain]]" );
puts( "token-source is _required_ for Kerberos and should be
your" );
puts( "current logon name (e.g., \"MYDOMAIN\\felixk\")." );
puts( "If -u is absent, your current credentials will be used." );*/
return 1;
}
initSecLib( hSecLib );
rc = WSAStartup( 2, &wsadata );
//wserr( rc, "WSAStartup" );
sock = socket( AF_INET, SOCK_STREAM, 0 );
if ( sock == INVALID_SOCKET )
{
rc = -1;
}
else
{
rc = 0;
}
addr.sin_family = AF_INET;
// try numeric IP address first (inet_addr)
naddr = inet_addr( server );
if ( naddr != INADDR_NONE )
{
addr.sin_addr.s_addr = naddr;
}
else
{
phe = gethostbyname( server );
// if ( phe == NULL )
// wserr( 1, "gethostbyname" );
addr.sin_addr.s_addr = *( (unsigned long *) (phe->h_addr) );
memcpy( (char *) &addr.sin_addr, phe->h_addr, phe->h_length );
}
// try numeric protocol first
port = atoi( portstr );
if ( port > 0 && port < 32768 )
addr.sin_port = htons( (short) port );
else
{
pse = getservbyname( portstr, "tcp" );
// if ( pse == NULL )
// wserr( 1, "getservbyname" );
addr.sin_port = pse->s_port;
}
CredHandle cred;
CtxtHandle cliCtx;
rc = connect( sock, (SOCKADDR *) &addr, sizeof addr );
//wserr( rc, "connect" );
struct sockaddr name;
int namelen = sizeof name;;
rc = getsockname( sock, &name, &namelen );
/*wserr( rc, "getsockname()" );
printf( "I am %u.%u.%u.%u\n", (unsigned int) (unsigned char)
name.sa_data[2],
(unsigned int) (unsigned char) name.sa_data[3], (unsigned int)
(unsigned char) name.sa_data[4],
(unsigned int) (unsigned char) name.sa_data[5] );*/
Ganesh_auth( sock, cred, cliCtx, tokenSource, user, pwd, domain ); //
this does the real work
// use the authenticated connection here
bool haveToken = false;
rc = recv( sock, (char *) &haveToken, sizeof haveToken, 0 );
if ( rc != sizeof haveToken )
{
rc = 999;
}
// wserr( 999, "result-recv" );
if ( haveToken )
puts( "That seems to have worked." );
else
puts( "Oops! Wrong user name or password?" );
// the server is probably impersonating us by now
// this is where the client and server talk business
// clean up
(pf->DeleteSecurityContext)( &cliCtx );
(pf->FreeCredentialHandle)( &cred );
rc = closesocket( sock );
wserr( rc, "closesocket" );
rc = WSACleanup();
wserr( rc, "WSACleanup" );
__try
{
FreeLibrary( hSecLib );
}
__except ( 1 )
{
// puts( "Freelibrary( security.dll ) caused an access violation.
Yuck." );
}
return 0;
}
struct CapName
{
DWORD bits;
const char *name;
const char *comment;
} capNames[] = {
{ SECPKG_FLAG_INTEGRITY, "SECPKG_FLAG_INTEGRITY", "Supports integrity
on messages" },
{ SECPKG_FLAG_PRIVACY, "SECPKG_FLAG_PRIVACY", "Supports privacy
(confidentiality)" },
{ SECPKG_FLAG_TOKEN_ONLY, "SECPKG_FLAG_TOKEN_ONLY", "Only security
token needed" },
{ SECPKG_FLAG_DATAGRAM, "SECPKG_FLAG_DATAGRAM", "Datagram RPC
support" },
{ SECPKG_FLAG_CONNECTION, "SECPKG_FLAG_CONNECTION", "Connection
oriented RPC support" },
{ SECPKG_FLAG_MULTI_REQUIRED, "SECPKG_FLAG_MULTI_REQUIRED", "Full 3-
leg required for re-auth." },
{ SECPKG_FLAG_CLIENT_ONLY, "SECPKG_FLAG_CLIENT_ONLY", "Server side
functionality not available" },
{ SECPKG_FLAG_EXTENDED_ERROR, "SECPKG_FLAG_EXTENDED_ERROR", "Supports
extended error msgs" },
{ SECPKG_FLAG_IMPERSONATION, "SECPKG_FLAG_IMPERSONATION", "Supports
impersonation" },
{ SECPKG_FLAG_ACCEPT_WIN32_NAME, "SECPKG_FLAG_ACCEPT_WIN32_NAME",
"Accepts Win32 names" },
{ SECPKG_FLAG_STREAM, "SECPKG_FLAG_STREAM", "Supports stream
semantics" },
{ SECPKG_FLAG_NEGOTIABLE, "SECPKG_FLAG_NEGOTIABLE", "Can be used by
the negotiate package" },
{ SECPKG_FLAG_GSS_COMPATIBLE, "SECPKG_FLAG_GSS_COMPATIBLE", "GSS
Compatibility Available" },
{ SECPKG_FLAG_LOGON, "SECPKG_FLAG_LOGON", "Supports common
LsaLogonUser" },
{ SECPKG_FLAG_ASCII_BUFFERS, "SECPKG_FLAG_ASCII_BUFFERS", "Token
Buffers are in ASCII" },
{ 0xffffffffL, "(fence)", "(fence)" }
};
void initSecLib( HINSTANCE& hSec )
{
PSecurityFunctionTable (*pSFT)( void );
hSec = LoadLibrary( "security.dll" );
pSFT = (PSecurityFunctionTable (*)( void )) GetProcAddress( hSec,
"InitSecurityInterfaceA" );
if ( pSFT == NULL )
{
exit( 1 );
}
pf = pSFT();
if ( pf == NULL )
{
exit( 1 );
}
SECURITY_STATUS rc;
DWORD numPacks = 0, i, j;
SecPkgInfo *pPacks = NULL;
rc = (pf->EnumerateSecurityPackages)( &numPacks, &pPacks );
if ( rc != 0 )
{
exit( 1 );
}
for ( i = 0; i < numPacks; ++ i )
{
for ( j = 0; capNames[j].bits != 0xffffffffL; ++ j )
{
//if ( ( capNames[j].bits & pPacks[i].fCapabilities ) == capNames
[j].bits )
//printf( " %s (%s)\n", capNames[j].name, capNames
[j].comment );
}
}
if ( pPacks != NULL )
(pf->FreeContextBuffer)( pPacks );
}
int main( int argc, char *argv[] )
{
int rc, port, addrlen;
HINSTANCE hSecLib;
CtxtHandle srvCtx;
bool haveToken;
SOCKET sock, s;
WSADATA wsadata;
PSERVENT pse;
SOCKADDR_IN addr;
HANDLE threadRet;
char buf[256];
DWORD bufsiz = sizeof buf;
if ( argc != 2 )
{
puts( "usage: server portnumber" );
return 1;
}
initSecLib( hSecLib );
rc = WSAStartup( 2, &wsadata );
wserr( rc, "WSAStartup" );
sock = socket( AF_INET, SOCK_STREAM, 0 );
if ( sock == INVALID_SOCKET )
wserr( 999, "socket" );
addr.sin_family = AF_INET;
addr.sin_addr.s_addr = INADDR_ANY;
// try numeric protocol first
port = atoi( argv[1] );
if ( port > 0 && port < 32768 )
addr.sin_port = htons( (short) port );
else
{
pse = getservbyname( argv[1], "tcp" );
if ( pse == NULL )
wserr( 1, "getservbyname" );
addr.sin_port = pse->s_port;
}
rc = bind( sock, (SOCKADDR *) &addr, sizeof addr );
wserr( rc, "bind" );
rc = listen( sock, 2 );
wserr( rc, "listen" );
CredHandle cred;
while ( 1 )
{
addrlen = sizeof addr;
s = accept( sock, (SOCKADDR *) &addr, &addrlen );
if ( s == INVALID_SOCKET )
wserr( s, "accept" );
haveToken = auth( s, cred, srvCtx );
// now we talk to the client
printf( "haveToken = %s\n\n", haveToken? "true": "false" );
send( s, (const char *) &haveToken, sizeof haveToken, 0 );
// clean up
// Modified by Ganesh
/*(pf->DeleteSecurityContext)( &srvCtx );
(pf->FreeCredentialHandle)( &cred );
closesocket( s );*/
break;
}
int j;
puts("/n/n Should I start client implemenation within server ?: ");
scanf("%d",&j);
LPVOID threadParam = &srvCtx;
DWORD threadId;
//PROCESS_INFORMATION Pi;
//STARTUPINFO Si;
//HANDLE hTokenNew = NULL, hTokenDup = NULL;
//ZeroMemory( &Pi,sizeof(Pi));
//ZeroMemory( &Si, sizeof( STARTUPINFO ) );
//Si.cb = sizeof( STARTUPINFO );
// Si.lpDesktop = "winsta0\\default";
//GetUserName( buf, &bufsiz );
//rc = (pf->ImpersonateSecurityContext)( &srvCtx );
//rc = GetLastError();
//GetUserName( buf, &bufsiz );
//rc = CreateProcess("C:\\WINDOWS\\system32\\notepad.exe","C:\\WINDOWS
\\system32\\notepad.exe", NULL, NULL, FALSE, NORMAL_PRIORITY_CLASS,
NULL, NULL, &Si, &Pi);
rc = GetLastError();
//threadRet = CreateThread( NULL, 0, (LPTHREAD_START_ROUTINE)
Ganesh_Client_Impl, threadParam, 0, &threadId);
j = Ganesh_Client_Impl(srvCtx);
WaitForSingleObject(threadRet,INFINITE);
CloseHandle( threadRet );
FreeLibrary( hSecLib );
return 0;
}
***************************************************************************************
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