nsICryptoHash Interface

 nsICryptoHash
 This interface provides crytographic hashing algorithms.

[scriptable, uuid(1e5b7c43-4688-45ce-92e1-77ed931e3bbe)]

Constants

 Hashing Algorithms.  These values are to be used by the
 |init| method to indicate which hashing function to
 use.  These values map directly onto the values defined
 in mozilla/security/nss/lib/cryptohi/hasht.h.

const short MD2 = 1

const short MD5 = 2

const short SHA1 = 3

const short SHA256 = 4

const short SHA384 = 5

const short SHA512 = 6

Methods

 Completes this hash object and produces the actual hash data.

 @param aASCII if true then the returned value is a base-64 
        encoded string.  if false, then the returned value is
        binary data.  

 @return a hash of the data that was read by this object.  This can
         be either binary data or base 64 encoded.

 @throws NS_ERROR_NOT_INITIALIZED if |init| has not been 
         called.

 NOTE: This method may be called any time after |init|
       is called.  This call resets the object to its
       pre-init state.

ACString finish(in PRBool aASCII)

 Initialize the hashing object. This method may be
 called multiple times with different algorithm types.

 @param aAlgorithm the algorithm type to be used.
        This value must be one of the above valid
        algorithm types.

 @throws NS_ERROR_INVALID_ARG if an unsupported algorithm
         type is passed.

 NOTE: This method or initWithString must be called
       before any other method on this interface is called.

void init(in unsigned long aAlgorithm)

 Initialize the hashing object. This method may be
 called multiple times with different algorithm types.

 @param aAlgorithm the algorithm type to be used.

 @throws NS_ERROR_INVALID_ARG if an unsupported algorithm
         type is passed.

 NOTE: This method or init must be called before any
       other method on this interface is called.

void initWithString(in ACString aAlgorithm)

 @param aData a buffer to calculate the hash over

 @param aLen the length of the buffer |aData|

 @throws NS_ERROR_NOT_INITIALIZED if |init| has not been 
         called.

void update([const, array, size_is(aLen)] in octet aData, in unsigned long aLen)

 Calculates and updates a new hash based on a given data stream.

 @param aStream an input stream to read from.

 @param aLen how much to read from the given |aStream|.  Passing
        PR_UINT32_MAX indicates that all data available will be used 
        to update the hash. 

 @throws NS_ERROR_NOT_INITIALIZED if |init| has not been 
         called.

 @throws NS_ERROR_NOT_AVAILABLE if the requested amount of 
         data to be calculated into the hash is not available.

void updateFromStream(in nsIInputStream aStream, in unsigned long aLen)