openssl/crypto/include/internal/md32_common.h
2018-12-06 15:57:31 +01:00

256 lines
7.9 KiB
C

/*
* Copyright 1999-2018 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the Apache License 2.0 (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
/*-
* This is a generic 32 bit "collector" for message digest algorithms.
* Whenever needed it collects input character stream into chunks of
* 32 bit values and invokes a block function that performs actual hash
* calculations.
*
* Porting guide.
*
* Obligatory macros:
*
* DATA_ORDER_IS_BIG_ENDIAN or DATA_ORDER_IS_LITTLE_ENDIAN
* this macro defines byte order of input stream.
* HASH_CBLOCK
* size of a unit chunk HASH_BLOCK operates on.
* HASH_LONG
* has to be at least 32 bit wide.
* HASH_CTX
* context structure that at least contains following
* members:
* typedef struct {
* ...
* HASH_LONG Nl,Nh;
* either {
* HASH_LONG data[HASH_LBLOCK];
* unsigned char data[HASH_CBLOCK];
* };
* unsigned int num;
* ...
* } HASH_CTX;
* data[] vector is expected to be zeroed upon first call to
* HASH_UPDATE.
* HASH_UPDATE
* name of "Update" function, implemented here.
* HASH_TRANSFORM
* name of "Transform" function, implemented here.
* HASH_FINAL
* name of "Final" function, implemented here.
* HASH_BLOCK_DATA_ORDER
* name of "block" function capable of treating *unaligned* input
* message in original (data) byte order, implemented externally.
* HASH_MAKE_STRING
* macro converting context variables to an ASCII hash string.
*
* MD5 example:
*
* #define DATA_ORDER_IS_LITTLE_ENDIAN
*
* #define HASH_LONG MD5_LONG
* #define HASH_CTX MD5_CTX
* #define HASH_CBLOCK MD5_CBLOCK
* #define HASH_UPDATE MD5_Update
* #define HASH_TRANSFORM MD5_Transform
* #define HASH_FINAL MD5_Final
* #define HASH_BLOCK_DATA_ORDER md5_block_data_order
*/
#include <openssl/crypto.h>
#if !defined(DATA_ORDER_IS_BIG_ENDIAN) && !defined(DATA_ORDER_IS_LITTLE_ENDIAN)
# error "DATA_ORDER must be defined!"
#endif
#ifndef HASH_CBLOCK
# error "HASH_CBLOCK must be defined!"
#endif
#ifndef HASH_LONG
# error "HASH_LONG must be defined!"
#endif
#ifndef HASH_CTX
# error "HASH_CTX must be defined!"
#endif
#ifndef HASH_UPDATE
# error "HASH_UPDATE must be defined!"
#endif
#ifndef HASH_TRANSFORM
# error "HASH_TRANSFORM must be defined!"
#endif
#ifndef HASH_FINAL
# error "HASH_FINAL must be defined!"
#endif
#ifndef HASH_BLOCK_DATA_ORDER
# error "HASH_BLOCK_DATA_ORDER must be defined!"
#endif
#define ROTATE(a,n) (((a)<<(n))|(((a)&0xffffffff)>>(32-(n))))
#if defined(DATA_ORDER_IS_BIG_ENDIAN)
# define HOST_c2l(c,l) (l =(((unsigned long)(*((c)++)))<<24), \
l|=(((unsigned long)(*((c)++)))<<16), \
l|=(((unsigned long)(*((c)++)))<< 8), \
l|=(((unsigned long)(*((c)++))) ) )
# define HOST_l2c(l,c) (*((c)++)=(unsigned char)(((l)>>24)&0xff), \
*((c)++)=(unsigned char)(((l)>>16)&0xff), \
*((c)++)=(unsigned char)(((l)>> 8)&0xff), \
*((c)++)=(unsigned char)(((l) )&0xff), \
l)
#elif defined(DATA_ORDER_IS_LITTLE_ENDIAN)
# define HOST_c2l(c,l) (l =(((unsigned long)(*((c)++))) ), \
l|=(((unsigned long)(*((c)++)))<< 8), \
l|=(((unsigned long)(*((c)++)))<<16), \
l|=(((unsigned long)(*((c)++)))<<24) )
# define HOST_l2c(l,c) (*((c)++)=(unsigned char)(((l) )&0xff), \
*((c)++)=(unsigned char)(((l)>> 8)&0xff), \
*((c)++)=(unsigned char)(((l)>>16)&0xff), \
*((c)++)=(unsigned char)(((l)>>24)&0xff), \
l)
#endif
/*
* Time for some action :-)
*/
int HASH_UPDATE(HASH_CTX *c, const void *data_, size_t len)
{
const unsigned char *data = data_;
unsigned char *p;
HASH_LONG l;
size_t n;
if (len == 0)
return 1;
l = (c->Nl + (((HASH_LONG) len) << 3)) & 0xffffffffUL;
if (l < c->Nl) /* overflow */
c->Nh++;
c->Nh += (HASH_LONG) (len >> 29); /* might cause compiler warning on
* 16-bit */
c->Nl = l;
n = c->num;
if (n != 0) {
p = (unsigned char *)c->data;
if (len >= HASH_CBLOCK || len + n >= HASH_CBLOCK) {
memcpy(p + n, data, HASH_CBLOCK - n);
HASH_BLOCK_DATA_ORDER(c, p, 1);
n = HASH_CBLOCK - n;
data += n;
len -= n;
c->num = 0;
/*
* We use memset rather than OPENSSL_cleanse() here deliberately.
* Using OPENSSL_cleanse() here could be a performance issue. It
* will get properly cleansed on finalisation so this isn't a
* security problem.
*/
memset(p, 0, HASH_CBLOCK); /* keep it zeroed */
} else {
memcpy(p + n, data, len);
c->num += (unsigned int)len;
return 1;
}
}
n = len / HASH_CBLOCK;
if (n > 0) {
HASH_BLOCK_DATA_ORDER(c, data, n);
n *= HASH_CBLOCK;
data += n;
len -= n;
}
if (len != 0) {
p = (unsigned char *)c->data;
c->num = (unsigned int)len;
memcpy(p, data, len);
}
return 1;
}
void HASH_TRANSFORM(HASH_CTX *c, const unsigned char *data)
{
HASH_BLOCK_DATA_ORDER(c, data, 1);
}
int HASH_FINAL(unsigned char *md, HASH_CTX *c)
{
unsigned char *p = (unsigned char *)c->data;
size_t n = c->num;
p[n] = 0x80; /* there is always room for one */
n++;
if (n > (HASH_CBLOCK - 8)) {
memset(p + n, 0, HASH_CBLOCK - n);
n = 0;
HASH_BLOCK_DATA_ORDER(c, p, 1);
}
memset(p + n, 0, HASH_CBLOCK - 8 - n);
p += HASH_CBLOCK - 8;
#if defined(DATA_ORDER_IS_BIG_ENDIAN)
(void)HOST_l2c(c->Nh, p);
(void)HOST_l2c(c->Nl, p);
#elif defined(DATA_ORDER_IS_LITTLE_ENDIAN)
(void)HOST_l2c(c->Nl, p);
(void)HOST_l2c(c->Nh, p);
#endif
p -= HASH_CBLOCK;
HASH_BLOCK_DATA_ORDER(c, p, 1);
c->num = 0;
OPENSSL_cleanse(p, HASH_CBLOCK);
#ifndef HASH_MAKE_STRING
# error "HASH_MAKE_STRING must be defined!"
#else
HASH_MAKE_STRING(c, md);
#endif
return 1;
}
#ifndef MD32_REG_T
# if defined(__alpha) || defined(__sparcv9) || defined(__mips)
# define MD32_REG_T long
/*
* This comment was originally written for MD5, which is why it
* discusses A-D. But it basically applies to all 32-bit digests,
* which is why it was moved to common header file.
*
* In case you wonder why A-D are declared as long and not
* as MD5_LONG. Doing so results in slight performance
* boost on LP64 architectures. The catch is we don't
* really care if 32 MSBs of a 64-bit register get polluted
* with eventual overflows as we *save* only 32 LSBs in
* *either* case. Now declaring 'em long excuses the compiler
* from keeping 32 MSBs zeroed resulting in 13% performance
* improvement under SPARC Solaris7/64 and 5% under AlphaLinux.
* Well, to be honest it should say that this *prevents*
* performance degradation.
*/
# else
/*
* Above is not absolute and there are LP64 compilers that
* generate better code if MD32_REG_T is defined int. The above
* pre-processor condition reflects the circumstances under which
* the conclusion was made and is subject to further extension.
*/
# define MD32_REG_T int
# endif
#endif