65 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			65 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
=pod
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=head1 NAME
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MDC2, MDC2_Init, MDC2_Update, MDC2_Final - MDC2 hash function
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=head1 SYNOPSIS
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 #include <openssl/mdc2.h>
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 unsigned char *MDC2(const unsigned char *d, unsigned long n,
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                  unsigned char *md);
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 void MDC2_Init(MDC2_CTX *c);
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 void MDC2_Update(MDC2_CTX *c, const unsigned char *data,
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                  unsigned long len);
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 void MDC2_Final(unsigned char *md, MDC2_CTX *c);
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=head1 DESCRIPTION
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MDC2 is a method to construct hash functions with 128 bit output from
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block ciphers.  These functions are an implementation of MDC2 with
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DES.
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MDC2() computes the MDC2 message digest of the B<n>
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bytes at B<d> and places it in B<md> (which must have space for
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MDC2_DIGEST_LENGTH == 16 bytes of output). If B<md> is NULL, the digest
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is placed in a static array.
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The following functions may be used if the message is not completely
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stored in memory:
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MDC2_Init() initializes a B<MDC2_CTX> structure.
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MDC2_Update() can be called repeatedly with chunks of the message to
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be hashed (B<len> bytes at B<data>).
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MDC2_Final() places the message digest in B<md>, which must have space
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for MDC2_DIGEST_LENGTH == 16 bytes of output, and erases the B<MDC2_CTX>.
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Applications should use the higher level functions
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L<EVP_DigestInit(3)|EVP_DigestInit(3)> etc. instead of calling the
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hash functions directly.
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=head1 RETURN VALUES
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MDC2() returns a pointer to the hash value. 
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MDC2_Init(), MDC2_Update() and MDC2_Final() do not return values.
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=head1 CONFORMING TO
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ISO/IEC 10118-2, with DES
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=head1 SEE ALSO
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L<sha(3)|sha(3)>, L<EVP_DigestInit(3)|EVP_DigestInit(3)>
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=head1 HISTORY
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MDC2(), MDC2_Init(), MDC2_Update() and MDC2_Final() are available since
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SSLeay 0.8.
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=cut
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