md4(3ext) [opensolaris man page]

md4(3EXT)						    Extended Library Functions							 md4(3EXT)

NAME

       md4, MD4Init, MD4Update, MD4Final - MD4 digest functions

SYNOPSIS

       cc [ flag ... ] file ... -lmd [ library ... ]
       #include <md4.h>

       void MD4Init(MD4_CTX *context);

       void MD4Update(MD4_CTX *context, unsigned char *input,
	    unsigned int inlen);

       void MD4Final(unsigned char *output, MD4_CTX *context);

DESCRIPTION

       The  MD4  functions  implement  the MD4 message-digest algorithm. The algorithm takes as input a message of arbitrary length and produces a
       "fingerprint" or "message digest" as output. The MD4 message-digest algorithm is intended for digital signature applications in which large
       files are "compressed" in a secure manner before being encrypted with a private (secret) key under a public-key cryptosystem such as RSA.

   MD4Init(), MD4Update(), MD4Final()
       The  MD4Init(),	MD4Update(), and MD4Final() functions allow an MD4 digest to be computed over multiple message blocks. Between blocks, the
       state of the MD4 computation is held in an MD4 context structure allocated by the caller. A complete digest computation consists  of  calls
       to MD4 functions in the following order: one call to MD4Init(), one or more calls to MD4Update(), and one call to MD4Final().

       The MD4Init() function initializes the MD4 context structure pointed to by context.

       The  MD4Update()  function  computes  a partial MD4 digest on the inlen-byte message block pointed to by input, and updates the MD4 context
       structure pointed to by context accordingly.

       The MD4Final() function generates the final MD4 digest, using the MD4 context structure pointed to by context. The MD4 digest is written to
       output.	After a call to MD4Final(), the state of the context structure is undefined. It must be reinitialized with MD4Init() before it can
       be used again.

RETURN VALUES

       These functions do not return a value.

SECURITY

       The MD4 digest algorithm is not currently considered cryptographically secure. It is included in libmd(3LIB) for use  by  legacy  protocols
       and systems only. It should not be used by new systems or protocols.

EXAMPLES

       Example 1 Authenticate a message found in multiple buffers

       The  following  is  a  sample function that must authenticate a message that is found in multiple buffers. The calling function provides an
       authentication buffer that will contain the result of the MD4 digest.

	 #include <sys/types.h>
	 #include <sys/uio.h>
	 #include <md4.h>

	 int
	 AuthenticateMsg(unsigned char *auth_buffer, struct iovec
			 *messageIov, unsigned int num_buffers)
	 {
	     MD4_CTX ctx;
	     unsigned int i;

	     MD4Init(&ctx);

	     for(i=0; i<num_buffers; i++)
	     {
		  MD4Update(&ctx, messageIov->iov_base,
			    messageIov->iov_len);
		  messageIov += sizeof(struct iovec);
	     }

	     MD4Final(auth_buffer, &ctx);

	     return 0;
	 }

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Committed 		   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       libmd(3LIB)

       RFC 1320

SunOS 5.11							    13 Nov 2007 							 md4(3EXT)

md4(3EXT)						    Extended Library Functions							 md4(3EXT)

NAME

       md4, MD4Init, MD4Update, MD4Final - MD4 digest functions

SYNOPSIS

       cc [ flag ... ] file ... -lmd [ library ... ]
       #include <md4.h>

       void MD4Init(MD4_CTX *context);

       void MD4Update(MD4_CTX *context, unsigned char *input,
	    unsigned int inlen);

       void MD4Final(unsigned char *output, MD4_CTX *context);

DESCRIPTION

       The  MD4  functions  implement  the MD4 message-digest algorithm. The algorithm takes as input a message of arbitrary length and produces a
       "fingerprint" or "message digest" as output. The MD4 message-digest algorithm is intended for digital signature applications in which large
       files are "compressed" in a secure manner before being encrypted with a private (secret) key under a public-key cryptosystem such as RSA.

   MD4Init(), MD4Update(), MD4Final()
       The  MD4Init(),	MD4Update(), and MD4Final() functions allow an MD4 digest to be computed over multiple message blocks. Between blocks, the
       state of the MD4 computation is held in an MD4 context structure allocated by the caller. A complete digest computation consists  of  calls
       to MD4 functions in the following order: one call to MD4Init(), one or more calls to MD4Update(), and one call to MD4Final().

       The MD4Init() function initializes the MD4 context structure pointed to by context.

       The  MD4Update()  function  computes  a partial MD4 digest on the inlen-byte message block pointed to by input, and updates the MD4 context
       structure pointed to by context accordingly.

       The MD4Final() function generates the final MD4 digest, using the MD4 context structure pointed to by context. The MD4 digest is written to
       output.	After a call to MD4Final(), the state of the context structure is undefined. It must be reinitialized with MD4Init() before it can
       be used again.

RETURN VALUES

       These functions do not return a value.

SECURITY

       The MD4 digest algorithm is not currently considered cryptographically secure. It is included in libmd(3LIB) for use  by  legacy  protocols
       and systems only. It should not be used by new systems or protocols.

EXAMPLES

       Example 1 Authenticate a message found in multiple buffers

       The  following  is  a  sample function that must authenticate a message that is found in multiple buffers. The calling function provides an
       authentication buffer that will contain the result of the MD4 digest.

	 #include <sys/types.h>
	 #include <sys/uio.h>
	 #include <md4.h>

	 int
	 AuthenticateMsg(unsigned char *auth_buffer, struct iovec
			 *messageIov, unsigned int num_buffers)
	 {
	     MD4_CTX ctx;
	     unsigned int i;

	     MD4Init(&ctx);

	     for(i=0; i<num_buffers; i++)
	     {
		  MD4Update(&ctx, messageIov->iov_base,
			    messageIov->iov_len);
		  messageIov += sizeof(struct iovec);
	     }

	     MD4Final(auth_buffer, &ctx);

	     return 0;
	 }

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Committed 		   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       libmd(3LIB)

       RFC 1320

SunOS 5.11							    13 Nov 2007 							 md4(3EXT)