org.ietf.jgss
Interface GSSContext
This interface encapsulates the GSS-API security context and provides
the security services (
wrap(byte[],int,int,MessageProp),
unwrap(byte[],int,int,MessageProp),
getMIC(byte[],int,int,MessageProp),
verifyMIC(byte[],int,int,byte[],int,int,MessageProp)) that
are available over the context. Security contexts are established
between peers using locally acquired credentials. Multiple contexts
may exist simultaneously between a pair of peers, using the same or
different set of credentials. GSS-API functions in a manner
independent of the underlying transport protocol and depends on its
calling application to transport its tokens between peers.
Before the context establishment phase is initiated, the context
initiator may request specific characteristics desired of the
established context. These can be set using the set methods. After
the context is established, the caller can check the actual
characteristic and services offered by the context using the query
methods.
The context establishment phase begins with the first call to the
init method by the context initiator. During this phase the
initSecContext(byte[],int,int) and
acceptSecContext(byte[],int,int) methods will produce GSS-API
authentication tokens which the calling application needs to send to
its peer. If an error occurs at any point, an exception will get
thrown and the code will start executing in a catch block. If not,
the normal flow of code continues and the application can make a call
to the
isEstablished() method. If this method returns false it
indicates that a token is needed from its peer in order to continue
the context establishment phase. A return value of true signals that
the local end of the context is established. This may still require
that a token be sent to the peer, if one is produced by GSS-API.
During the context establishment phase, the
isProtReady()
method may be called to determine if the context can be used for the
per-message operations. This allows applications to use per-message
operations on contexts which aren't fully established.
After the context has been established or the
isProtReady()
method returns
true, the query routines can be invoked to
determine the actual characteristics and services of the established
context. The application can also start using the per-message methods
of
wrap(byte[],int,int,MessageProp) and
getMIC(byte[],int,int,MessageProp) to obtain
cryptographic operations on application supplied data.
When the context is no longer needed, the application should call
dispose() to release any system resources the context may be
using.
Example Code
GSSManager mgr = GSSManager.getInstance();
// start by creating the name for a service entity
GSSName targetName = mgr.createName("service@host",
GSSName.NT_HOSTBASED_SERVICE);
// create a context using default credentials for the above entity
// and the implementation specific default mechanism
GSSContext context = mgr.createContext(targetName,
null, // default mechanism
null, // default credentials
GSSContext.INDEFINITE_LIFETIME);
// set desired context options - all others are false by default
context.requestConf(true);
context.requestMutualAuth(true);
context.requestReplayDet(true);
context.requestSequenceDet(true);
// establish a context between peers - using byte arrays
byte []inTok = new byte[0];
try
{
do
{
byte[] outTok = context.initSecContext(inTok, 0,
inTok.length);
// send the token if present
if (outTok != null)
sendToken(outTok);
// check if we should expect more tokens
if (context.isEstablished())
break;
// another token expected from peer
inTok = readToken();
}
while (true);
}
catch (GSSException e)
{
print("GSSAPI error: " + e.getMessage());
}
// display context information
print("Remaining lifetime in seconds = " + context.getLifetime());
print("Context mechanism = " + context.getMech().toString());
print("Initiator = " + context.getSrcName().toString());
print("Acceptor = " + context.getTargName().toString());
if (context.getConfState())
print("Confidentiality security service available");
if (context.getIntegState())
print("Integrity security service available");
// perform wrap on an application supplied message, appMsg,
// using QOP = 0, and requesting privacy service
byte[] appMsg ...
MessageProp mProp = new MessageProp(0, true);
byte[] tok = context.wrap(appMsg, 0, appMsg.length, mProp);
if (mProp.getPrivacy())
print("Message protected with privacy.");
sendToken(tok);
// release the local-end of the context
context.dispose();
static int | DEFAULT_LIFETIME- A lifetime constant representing the default context lifetime.
|
static int | INDEFINITE_LIFETIME- A lifetime constant representing indefinite context lifetime.
|
byte[] | acceptSecContext(byte[] inTok, int offset, int len)- Called by the context acceptor upon receiving a token from the peer.
|
void | acceptSecContext(InputStream inStream, OutputStream outStream)- Called by the context acceptor upon receiving a token from the peer.
|
void | dispose()- Releases any system resources and cryptographic information stored in
the context object.
|
byte[] | export()- Provided to support the sharing of work between multiple processes.
|
boolean | getAnonymityState()- Returns "true" if this is an anonymous context.
|
boolean | getConfState()- Returns the confidentiality service state over the context.
|
boolean | getCredDelegState()- Returns the state of the delegated credentials for the context.
|
GSSCredential | getDelegCred()- Returns the delegated credential object on the acceptor's side.
|
boolean | getIntegState()- Returns the integrity service state over the context.
|
int | getLifetime()- Returns the context lifetime in seconds.
|
byte[] | getMIC(byte[] inMsg, int offset, int len, MessageProp msgProp)- Returns a token containing a cryptographic MIC for the supplied
message, for transfer to the peer application.
|
void | getMIC(InputStream inStream, OutputStream outStream, MessageProp mgProp)- Produces a token containing a cryptographic MIC for the supplied
message, for transfer to the peer application.
|
Oid | getMech()- Returns the mechanism oid for this context.
|
boolean | getMutualAuthState()- Returns the state of the mutual authentication option for the
context.
|
boolean | getReplayDetState()- Returns the state of the replay detection option for the context.
|
boolean | getSequenceDetState()- Returns the state of the sequence detection option for the context.
|
GSSName | getSrcName()- Returns the name of the context initiator.
|
GSSName | getTargName()- Returns the name of the context target (acceptor).
|
int | getWrapSizeLimit(int qop, boolean confReq, int maxTokenSize)- Returns the maximum message size that, if presented to the
wrap(byte[],int,int,MessageProp) method with
the same confReq and qop parameters, will result in an
output token containing no more than the maxTokenSize bytes.
This call is intended for use by applications that communicate over
protocols that impose a maximum message size.
|
byte[] | initSecContext(byte[] inputBuf, int offset, int len)- Called by the context initiator to start the context creation
process.
|
int | initSecContext(InputStream inStream, OutputStream outStream)- Called by the context initiator to start the context creation
process.
|
boolean | isEstablished()- Used during context establishment to determine the state of the
context.
|
boolean | isInitiator()- Returns "true" if this is the initiator of the context.
|
boolean | isProtReady()- Returns "true" if the per message operations can be applied over
the context.
|
boolean | isTransferable()- Returns "true" if the context is transferable to other processes
through the use of the
export() method.
|
void | requestAnonymity(boolean state)- Requests anonymous support over the context.
|
void | requestConf(boolean state)- Requests that confidentiality service be available over the context.
|
void | requestCredDeleg(boolean state)- Sets the request state for the credential delegation flag for the
context.
|
void | requestInteg(boolean state)- Requests that integrity services be available over the context.
|
void | requestLifetime(int lifetime)- Sets the desired lifetime for the context in seconds.
|
void | requestMutualAuth(boolean state)- Sets the request state of the mutual authentication flag for the
context.
|
void | requestReplayDet(boolean state)- Sets the request state of the replay detection service for the
context.
|
void | requestSequenceDet(boolean state)- Sets the request state for the sequence checking service of the
context.
|
void | setChannelBinding(ChannelBinding cb)- Sets the channel bindings to be used during context establishment.
|
byte[] | unwrap(byte[] inBuf, int offset, int len, MessageProp msgProp)- Used by the peer application to process tokens generated with the
wrap call.
|
void | unwrap(InputStream inStream, OutputStream outStream, MessageProp msgProp)- Used by the peer application to process tokens generated with the
wrap call.
|
void | verifyMIC(byte[] inTok, int tokOffset, int tokLen, byte[] inMsg, int msgOffset, int msgLen, MessageProp msgProp)- Verifies the cryptographic MIC, contained in the token parameter,
over the supplied message.
|
void | verifyMIC(InputStream tokStream, InputStream msgStream, MessageProp msgProp)- Verifies the cryptographic MIC, contained in the token parameter,
over the supplied message.
|
byte[] | wrap(byte[] inBuf, int offset, int len, MessageProp msgProp)- Applies per-message security services over the established security
context.
|
void | wrap(InputStream inStream, OutputStream outStream, MessageProp msgProp)- Allows to apply per-message security services over the established
security context.
|
DEFAULT_LIFETIME
public static final int DEFAULT_LIFETIME
A lifetime constant representing the default context lifetime.
INDEFINITE_LIFETIME
public static final int INDEFINITE_LIFETIME
A lifetime constant representing indefinite context lifetime.
acceptSecContext
public byte[] acceptSecContext(byte[] inTok,
int offset,
int len)
throws GSSException Called by the context acceptor upon receiving a token from the peer.
This call is equivalent to the stream based method except that the
token buffers are handled as byte arrays instead of using stream
objects.
This method may return an output token which the application will
need to send to the peer for further processing by the init call.
null return value indicates that no token needs to be
sent to the peer. The application can call
isEstablished()
to determine if the context establishment phase is complete for this
peer. A return value of
false from
isEstablished()
indicates that more tokens are expected to be supplied to this
method.
Note that it is possible that acceptSecContext() return a token for
the peer, and isEstablished() return
true also. This
indicates that the token needs to be sent to the peer, but the local
end of the context is now fully established.
Upon completion of the context establishment, the available context
options may be queried through the get methods.
inTok - Token generated by the peer.offset - The offset within the inTok where the token begins.len - The length of the token within the inTok (starting
at the offset).
- The output token, if any.
acceptSecContext
public void acceptSecContext(InputStream inStream,
OutputStream outStream)
throws GSSException Called by the context acceptor upon receiving a token from the peer.
This call is equivalent to the byte array method. It may write an
output token to the outStream, which the application will need to
send to the peer for processing by its initSecContext method.
Typically, the application would do so by calling the
OutputStream.flush() method on an OutputStream that encapsulates the
connection between the two peers. The application can call
isEstablished() to determine if the context establishment phase is
complete for this peer. A return value of
false from
isEstablished() indicates that more tokens are expected to be
supplied to this method.
Note that it is possible that acceptSecContext() return a token for
the peer, and isEstablished() return
true also. This
indicates that the token needs to be sent to the peer, but the local
end of the context is now fully established.
The GSS-API authentication tokens contain a definitive start and end.
This method will attempt to read one of these tokens per invocation,
and may block on the stream if only part of the token is available.
Upon completion of the context establishment, the available context
options may be queried through the get methods.
inStream - Contains the token generated by the peer.outStream - Output stream where the output token will be written.
During the final stage of context establishment, there
may be no bytes written.
dispose
public void dispose()
throws GSSException Releases any system resources and cryptographic information stored in
the context object. This will invalidate the context.
export
public byte[] export()
throws GSSException Provided to support the sharing of work between multiple processes.
This routine will typically be used by the context-acceptor, in an
application where a single process receives incoming connection
requests and accepts security contexts over them, then passes the
established context to one or more other processes for message
exchange.
This method deactivates the security context and creates an
interprocess token which, when passed to the byte array constructor
of the GSSContext interface in another process, will re-activate the
context in the second process. Only a single instantiation of a
given context may be active at any one time; a subsequent attempt by
a context exporter to access the exported security context will fail.
The implementation may constrain the set of processes by which the
interprocess token may be imported, either as a function of local
security policy, or as a result of implementation decisions. For
example, some implementations may constrain contexts to be passed
only between processes that run under the same account, or which are
part of the same process group.
The interprocess token may contain security-sensitive information
(for example cryptographic keys). While mechanisms are encouraged to
either avoid placing such sensitive information within interprocess
tokens, or to encrypt the token before returning it to the
application, in a typical GSS-API implementation this may not be
possible. Thus the application must take care to protect the
interprocess token, and ensure that any process to which the token is
transferred is trustworthy.
getAnonymityState
public boolean getAnonymityState()
Returns "true" if this is an anonymous context. When issued before
context establishment completes or when the isProtReady method
returns "false", it returns the desired state, otherwise it will
indicate the actual state over the established context.
- True if this is an anonymous context.
getConfState
public boolean getConfState()
Returns the confidentiality service state over the context. When
issued before context establishment completes or when the isProtReady
method returns "false", it returns the desired state, otherwise it
will indicate the actual state over the established context.
- True the confidentiality service state.
getCredDelegState
public boolean getCredDelegState()
Returns the state of the delegated credentials for the context.
When issued before context establishment is completed or when the
isProtReady method returns "false", it returns the desired state,
otherwise it will indicate the actual state over the established
context.
- The state of the delegated credentials for the context.
getDelegCred
public GSSCredential getDelegCred()
throws GSSException Returns the delegated credential object on the acceptor's side.
To check for availability of delegated credentials call
getDelegCredState(). This call is only valid on fully
established contexts.
- The delegated credential object.
getIntegState
public boolean getIntegState()
Returns the integrity service state over the context. When issued
before context establishment completes or when the isProtReady method
returns "false", it returns the desired state, otherwise it will
indicate the actual state over the established context.
- The integrity service state.
getLifetime
public int getLifetime()
Returns the context lifetime in seconds. When issued before context
establishment completes or when the isProtReady method returns
"false", it returns the desired lifetime, otherwise it will indicate
the remaining lifetime for the context.
getMIC
public byte[] getMIC(byte[] inMsg,
int offset,
int len,
MessageProp msgProp)
throws GSSException Returns a token containing a cryptographic MIC for the supplied
message, for transfer to the peer application. Unlike wrap, which
encapsulates the user message in the returned token, only the message
MIC is returned in the output token. This method is identical in
functionality to its stream counterpart.
Note that privacy can only be applied through the wrap call.
Since some application-level protocols may wish to use tokens emitted
by getMIC to provide "secure framing", implementations should support
derivation of MICs from zero-length messages.
inMsg - Message to generate MIC over.offset - The offset within the inMsg where the token begins.len - The length of the token within the inMsg (starting at
the offset).msgProp - Instance of MessageProp that is used by the
application to set the desired QOP. Set the desired
QOP to 0 in msgProp to request the default QOP.
Alternatively pass in null for msgProp to
request default QOP.
getMIC
public void getMIC(InputStream inStream,
OutputStream outStream,
MessageProp mgProp)
throws GSSException Produces a token containing a cryptographic MIC for the supplied
message, for transfer to the peer application. Unlike wrap, which
encapsulates the user message in the returned token, only the message
MIC is produced in the output token. This method is identical in
functionality to its byte array counterpart.
Note that privacy can only be applied through the wrap call.
Since some application-level protocols may wish to use tokens emitted
by getMIC to provide "secure framing", implementations should support
derivation of MICs from zero-length messages.
inStream - Input stream containing the message to generate
the MIC over.outStream - Output stream to write the GSS-API output token to.
getMech
public Oid getMech()
throws GSSException Returns the mechanism oid for this context. This method may be called
before the context is fully established, but the mechanism returned
may change on successive calls in negotiated mechanism case.
getMutualAuthState
public boolean getMutualAuthState()
Returns the state of the mutual authentication option for the
context. When issued before context establishment completes or when
the isProtReady method returns "false", it returns the desired state,
otherwise it will indicate the actual state over the established
context.
- The state of the mutual authentication option.
getReplayDetState
public boolean getReplayDetState()
Returns the state of the replay detection option for the context.
When issued before context establishment completes or when the
isProtReady method returns "false", it returns the desired state,
otherwise it will indicate the actual state over the established
context.
- The state of the replay detection option.
getSequenceDetState
public boolean getSequenceDetState()
Returns the state of the sequence detection option for the context.
When issued before context establishment completes or when the
isProtReady method returns "false", it returns the desired state,
otherwise it will indicate the actual state over the established
context.
- The state of the sequence detection option.
getSrcName
public GSSName getSrcName()
throws GSSException Returns the name of the context initiator. This call is valid only
after the context is fully established or the isProtReady method
returns "true". It is guaranteed to return an MN.
- The name of the context initiator.
getTargName
public GSSName getTargName()
throws GSSException Returns the name of the context target (acceptor). This call is
valid only after the context is fully established or the isProtReady
method returns "true". It is guaranteed to return an MN.
- The name of the context target.
getWrapSizeLimit
public int getWrapSizeLimit(int qop,
boolean confReq,
int maxTokenSize)
throws GSSException Returns the maximum message size that, if presented to the
wrap(byte[],int,int,MessageProp) method with
the same
confReq and
qop parameters, will result in an
output token containing no more than the
maxTokenSize bytes.
This call is intended for use by applications that communicate over
protocols that impose a maximum message size. It enables the
application to fragment messages prior to applying protection.
GSS-API implementations are recommended but not required to detect
invalid QOP values when getWrapSizeLimit is called. This routine
guarantees only a maximum message size, not the availability of
specific QOP values for message protection.
Successful completion of this call does not guarantee that wrap will
be able to protect a message of the computed length, since this
ability may depend on the availability of system resources at the
time that wrap is called. However, if the implementation itself
imposes an upper limit on the length of messages that may be
processed by wrap, the implementation should not return a value that
is greater than this length.
qop - Indicates the level of protection wrap will be asked
to provide.confReq - Indicates if wrap will be asked to provide privacy
service.maxTokenSize - The desired maximum size of the token emitted
by wrap(byte[],int,int,MessageProp).
- The maximum wrapped output size.
initSecContext
public byte[] initSecContext(byte[] inputBuf,
int offset,
int len)
throws GSSException Called by the context initiator to start the context creation
process. This is equivalent to the stream based method except that
the token buffers are handled as byte arrays instead of using stream
objects. This method may return an output token which the
application will need to send to the peer for processing by the
accept call. Typically, the application would do so by calling the
OutputStream.flush() method on an OutputStream that
encapsulates the connection between the two peers. The application
can call
isEstablished() to determine if the context
establishment phase is complete for this peer. A return value of
false from
isEstablished() indicates that more
tokens are expected to be supplied to the initSecContext() method. Note
that it is possible that the initSecContext() method return a token for
the peer, and
isEstablished() to return
true also.
This indicates that the token needs to be sent to the peer, but the local
end of the context is now fully established.
Upon completion of the context establishment, the available context
options may be queried through the get methods.
inputBuf - Token generated by the peer. This parameter is ignored
on the first call.offset - The offset within the inputBuf where the token
begins.len - The length of the token within the inputBuf
(starting at the offset).
- The output token, if any.
initSecContext
public int initSecContext(InputStream inStream,
OutputStream outStream)
throws GSSException Called by the context initiator to start the context creation
process. This is equivalent to the byte array based method. This
method may write an output token to the
outStream, which the
application will need to send to the peer for processing by the
accept call. Typically, the application would do so by calling the
OutputStream.flush() method on an OutputStream that encapsulates
the connection between the two peers. The application can call
isEstablished() to determine if the context establishment phase is
complete for this peer. A return value of
false from
isEstablished indicates that more tokens are expected to be supplied
to the initSecContext() method. Note that it is possible that the
initSecContext() method return a token for the peer, and #isEstablished() return
true also. This indicates that
the token needs to be sent to the peer, but the local end of the context
is now fully established.
The GSS-API authentication tokens contain a definitive start and end.
This method will attempt to read one of these tokens per invocation,
and may block on the stream if only part of the token is available.
Upon completion of the context establishment, the available context
options may be queried through the get methods.
@param inStream Contains the token generated by the peer. This
parameter is ignored on the first call.
@param outStream Output stream where the output token will be written.
During the final stage of context establishment, there
may be no bytes written.
@return The number of bytes written to
outStream, or 0 if no
token is written.
@throws GSSException If this operation fails.
isEstablished
public boolean isEstablished()
- True of this context is fully established on this side.
isInitiator
public boolean isInitiator()
throws GSSException Returns "true" if this is the initiator of the context. This call is
only valid after the context creation process has started.
- True if this is the initiator.
isProtReady
public boolean isProtReady()
Returns "true" if the per message operations can be applied over
the context. Some mechanisms may allow the usage of per-message
operations before the context is fully established. This will also
indicate that the get methods will return actual context state
characteristics instead of the desired ones.
- True if the per message operations can be applied over
the context.
isTransferable
public boolean isTransferable()
throws GSSException Returns "true" if the context is transferable to other processes
through the use of the
export() method. This call is only
valid on fully established contexts.
- True if the context is transferable.
requestAnonymity
public void requestAnonymity(boolean state)
throws GSSException Requests anonymous support over the context. This method is only
valid before the context creation process begins and only for the
initiator.
state - Boolean representing if anonymity support is requested.
requestConf
public void requestConf(boolean state)
throws GSSException Requests that confidentiality service be available over the context.
This method is only valid before the context creation process begins
and only for the initiator.
state - Boolean indicating if confidentiality services are to
be requested for the context.
requestCredDeleg
public void requestCredDeleg(boolean state)
throws GSSException Sets the request state for the credential delegation flag for the
context. This method is only valid before the context creation
process begins and only for the initiator.
state - Boolean representing if credential delegation is
desired.
requestInteg
public void requestInteg(boolean state)
throws GSSException Requests that integrity services be available over the context. This
method is only valid before the context creation process begins and
only for the initiator.
state - Boolean indicating if integrity services are to be
requested for the context.
requestLifetime
public void requestLifetime(int lifetime)
throws GSSException Sets the desired lifetime for the context in seconds. This method is
only valid before the context creation process begins and only for
the initiator. Use
INDEFINITE_LIFETIME and
DEFAULT_LIFETIME to request indefinite or default context lifetime.
lifetime - The desired context lifetime in seconds.
requestMutualAuth
public void requestMutualAuth(boolean state)
throws GSSException Sets the request state of the mutual authentication flag for the
context. This method is only valid before the context creation
process begins and only for the initiator.
state - Boolean representing if mutual authentication should
be requested during context establishment.
requestReplayDet
public void requestReplayDet(boolean state)
throws GSSException Sets the request state of the replay detection service for the
context. This method is only valid before the context creation
process begins and only for the initiator.
state - Boolean representing if replay detection is desired
over the established context.
requestSequenceDet
public void requestSequenceDet(boolean state)
throws GSSException Sets the request state for the sequence checking service of the
context. This method is only valid before the context creation
process begins and only for the initiator.
state - Boolean representing if sequence detection is desired
over the established context.
setChannelBinding
public void setChannelBinding(ChannelBinding cb)
throws GSSException Sets the channel bindings to be used during context establishment.
This method is only valid before the context creation process begins.
cb - Channel bindings to be used.
unwrap
public byte[] unwrap(byte[] inBuf,
int offset,
int len,
MessageProp msgProp)
throws GSSException Used by the peer application to process tokens generated with the
wrap call. This call is equal in functionality to its stream
counterpart. The method will return the message supplied in the peer
application to the wrap call, verifying the embedded MIC.
The
MessageProp object is instantiated by the application and
is used by the underlying mechanism to return information to the caller
such as the QOP, whether confidentiality was applied to the message, and
other supplementary message state information.
Since some application-level protocols may wish to use tokens emitted
by wrap to provide "secure framing", implementations should support
the wrapping and unwrapping of zero-length messages.
inBuf - GSS-API wrap token received from peer.offset - The offset within the inBuf where the token begins.len - The length of the token within the inBuf (starting at
the offset).msgProp - Upon return from the method, this object will contain
the applied QOP, the privacy state of the message, and
supplementary information stating whether the token was
a duplicate, old, out of sequence or arriving after a gap.
unwrap
public void unwrap(InputStream inStream,
OutputStream outStream,
MessageProp msgProp)
throws GSSException Used by the peer application to process tokens generated with the
wrap call. This call is equal in functionality to its byte array
counterpart. It will produce the message supplied in the peer
application to the wrap call, verifying the embedded MIC.
The
MessageProp object is instantiated by the application
and is used by the underlying mechanism to return information to the
caller such as the QOP, whether confidentiality was applied to the
message, and other supplementary message state information.
Since some application-level protocols may wish to use tokens emitted
by wrap to provide "secure framing", implementations should support
the wrapping and unwrapping of zero-length messages.
inStream - Input stream containing the GSS-API wrap token
received from the peer.outStream - The output stream to write the application message to.msgProp - Upon return from the method, this object will contain
the applied QOP, the privacy state of the message, and
supplementary information stating whether the token was
a duplicate, old, out of sequence or arriving after a gap.
verifyMIC
public void verifyMIC(byte[] inTok,
int tokOffset,
int tokLen,
byte[] inMsg,
int msgOffset,
int msgLen,
MessageProp msgProp)
throws GSSException Verifies the cryptographic MIC, contained in the token parameter,
over the supplied message. This method is equivalent in
functionality to its stream counterpart.
The MessageProp object is instantiated by the application and is used
by the underlying mechanism to return information to the caller such
as the QOP indicating the strength of protection that was applied to
the message and other supplementary message state information.
Since some application-level protocols may wish to use tokens emitted
by getMIC to provide "secure framing", implementations should support
the calculation and verification of MICs over zero-length messages.
inTok - Token generated by peer's getMIC method.tokOffset - The offset within the inTok where the token begins.tokLen - The length of the token within the inTok (starting at
the offset).inMsg - Application message to verify the cryptographic MIC
over.msgOffset - The offset within the inMsg where the message begins.msgLen - The length of the message within the inMsg (starting
at the offset).msgProp - Upon return from the method, this object will contain
the applied QOP and supplementary information
stating whether the token was a duplicate, old, out
of sequence or arriving after a gap. The
confidentiality state will be set to false.
verifyMIC
public void verifyMIC(InputStream tokStream,
InputStream msgStream,
MessageProp msgProp)
throws GSSException Verifies the cryptographic MIC, contained in the token parameter,
over the supplied message. This method is equivalent in
functionality to its byte array counterpart.
The MessageProp object is instantiated by the application and is used
by the underlying mechanism to return information to the caller such
as the QOP indicating the strength of protection that was applied to
the message and other supplementary message state information.
Since some application-level protocols may wish to use tokens emitted
by getMIC to provide "secure framing", implementations should support
the calculation and verification of MICs over zero-length messages.
tokStream - Input stream containing the token generated by peer's
getMIC method.msgStream - Input stream containing the application message to
verify the cryptographic MIC over.msgProp - Upon return from the method, this object will contain
the applied QOP and supplementary information
stating whether the token was a duplicate, old, out of
sequence or arriving after a gap. The confidentiality
state will be set to false.
wrap
public byte[] wrap(byte[] inBuf,
int offset,
int len,
MessageProp msgProp)
throws GSSException Applies per-message security services over the established security
context. The method will return a token with a cryptographic MIC and
may optionally encrypt the specified
inBuf. This method is
equivalent in functionality to its stream counterpart. The returned
byte array will contain both the MIC and the message.
The
MessageProp object is instantiated by the application
and used to specify a QOP value which selects cryptographic algorithms,
and a privacy service to optionally encrypt the message. The underlying
mechanism that is used in the call may not be able to provide the
privacy service. It sets the actual privacy service that it does
provide in this
MessageProp object which the caller should then
query upon return. If the mechanism is not able to provide the
requested QOP, it throws a
GSSException with the
GSSException.BAD_QOP code.
Since some application-level protocols may wish to use tokens emitted
by wrap to provide "secure framing", implementations should support
the wrapping of zero-length messages.
The application will be responsible for sending the token to the
peer.
inBuf - Application data to be protected.offset - The offset within the inBuf where the data begins.len - The length of the data within the inBuf (starting at
the offset).msgProp - Instance of MessageProp that is used by the
application to set the desired QOP and privacy state.
Set the desired QOP to 0 to request the default QOP.
Upon return from this method, this object will contain
the the actual privacy state that was applied to the
message by the underlying mechanism.
wrap
public void wrap(InputStream inStream,
OutputStream outStream,
MessageProp msgProp)
throws GSSException Allows to apply per-message security services over the established
security context. The method will produce a token with a
cryptographic MIC and may optionally encrypt the message in inStream.
The outStream will contain both the MIC and the message.
The
MessageProp object is instantiated by the application and
used to specify a QOP value which selects cryptographic algorithms, and
a privacy service to optionally encrypt the message. The underlying
mechanism that is used in the call may not be able to provide the
privacy service. It sets the actual privacy service that it does
provide in this MessageProp object which the caller should then query
upon return. If the mechanism is not able to provide the requested
QOP, it throws a
GSSException with the
GSSException.BAD_QOP code.
Since some application-level protocols may wish to use tokens emitted
by wrap to provide "secure framing", implementations should support
the wrapping of zero-length messages.
The application will be responsible for sending the token to the
peer.
inStream - Input stream containing the application data to be
protected.outStream - The output stream to write the protected message to.
The application is responsible for sending this to the
other peer for processing in its unwrap method.msgProp - Instance of MessageProp that is used by the
application to set the desired QOP and privacy state.
Set the desired QOP to 0 to request the default QOP.
Upon return from this method, this object will contain
the the actual privacy state that was applied to the
message by the underlying mechanism.
GSSContext.java -- The GSS context interface.
Copyright (C) 2004 Free Software Foundation, Inc.
This file is part of GNU Classpath.
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it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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02110-1301 USA.
Linking this library statically or dynamically with other modules is
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