ctx_sha.c

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/****************************************************************************
*                                                                           *
*                           cryptlib SHA Hash Routines                      *
*                       Copyright Peter Gutmann 1992-2005                   *
*                                                                           *
****************************************************************************/

#if defined( INC_ALL )
  #include "crypt.h"
  #include "context.h"
  #include "sha.h"
#else
  #include "crypt.h"
  #include "context/context.h"
  #include "crypt/sha.h"
#endif /* Compiler-specific includes */

#define HASH_STATE_SIZE     sizeof( SHA_CTX )

/****************************************************************************
*                                                                           *
*                               SHA Self-test Routines                      *
*                                                                           *
****************************************************************************/

#ifndef CONFIG_NO_SELFTEST

/* Test the SHA output against the test vectors given in FIPS 180-1.  We skip
   the third test since this takes several seconds to execute, which leads to
   an unacceptable delay */

static const struct {
    const char FAR_BSS *data;               /* Data to hash */
    const int length;                       /* Length of data */
    const BYTE digest[ SHA_DIGEST_LENGTH ]; /* Digest of data */
    } FAR_BSS digestValues[] = {
    { "abc", 3,
      { 0xA9, 0x99, 0x3E, 0x36, 0x47, 0x06, 0x81, 0x6A,
        0xBA, 0x3E, 0x25, 0x71, 0x78, 0x50, 0xC2, 0x6C,
        0x9C, 0xD0, 0xD8, 0x9D } },
    { "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq", 56,
      { 0x84, 0x98, 0x3E, 0x44, 0x1C, 0x3B, 0xD2, 0x6E,
        0xBA, 0xAE, 0x4A, 0xA1, 0xF9, 0x51, 0x29, 0xE5,
        0xE5, 0x46, 0x70, 0xF1 } },
/*  { "aaaaa...", 1000000L,
      { 0x34, 0xAA, 0x97, 0x3C, 0xD4, 0xC4, 0xDA, 0xA4,
        0xF6, 0x1E, 0xEB, 0x2B, 0xDB, 0xAD, 0x27, 0x31,
        0x65, 0x34, 0x01, 0x6F } }, */
    { NULL, 0, { 0 } }
    };

static int selfTest( void )
    {
    const CAPABILITY_INFO *capabilityInfo = getSHA1Capability();
    BYTE hashState[ HASH_STATE_SIZE + 8 ];
    int i, status;

    /* Test SHA-1 against values given in FIPS 180-1 */
    for( i = 0; digestValues[ i ].data != NULL; i++ )
        {
        status = testHash( capabilityInfo, hashState, digestValues[ i ].data, 
                           digestValues[ i ].length, digestValues[ i ].digest );
        if( cryptStatusError( status ) )
            return( status );
        }

    return( CRYPT_OK );
    }
#else
    #define selfTest    NULL
#endif /* !CONFIG_NO_SELFTEST */

/****************************************************************************
*                                                                           *
*                               Control Routines                            *
*                                                                           *
****************************************************************************/

/* Return context subtype-specific information */

CHECK_RETVAL STDC_NONNULL_ARG( ( 3 ) ) \
static int getInfo( IN_ENUM( CAPABILITY_INFO ) const CAPABILITY_INFO_TYPE type, 
                    INOUT_OPT CONTEXT_INFO *contextInfoPtr,
                    OUT void *data, 
                    IN_INT_Z const int length )
    {
    assert( contextInfoPtr == NULL || \
            isWritePtr( contextInfoPtr, sizeof( CONTEXT_INFO ) ) );
    assert( ( length == 0 && isWritePtr( data, sizeof( int ) ) ) || \
            ( length > 0 && isWritePtr( data, length ) ) );

    REQUIRES( type > CAPABILITY_INFO_NONE && type < CAPABILITY_INFO_LAST );

    if( type == CAPABILITY_INFO_STATESIZE )
        {
        int *valuePtr = ( int * ) data;

        *valuePtr = HASH_STATE_SIZE;

        return( CRYPT_OK );
        }

    return( getDefaultInfo( type, contextInfoPtr, data, length ) );
    }

/****************************************************************************
*                                                                           *
*                               SHA Hash Routines                           *
*                                                                           *
****************************************************************************/

/* Hash data using SHA */

static int hash( CONTEXT_INFO *contextInfoPtr, BYTE *buffer, int noBytes )
    {
    SHA_CTX *shaInfo = ( SHA_CTX * ) contextInfoPtr->ctxHash->hashInfo;

    /* If the hash state was reset to allow another round of hashing,
       reinitialise things */
    if( !( contextInfoPtr->flags & CONTEXT_FLAG_HASH_INITED ) )
        SHA1_Init( shaInfo );

    if( noBytes > 0 )
        {
        SHA1_Update( shaInfo, buffer, noBytes );
        }
    else
        SHA1_Final( contextInfoPtr->ctxHash->hash, shaInfo );

    return( CRYPT_OK );
    }

/* Internal API: Hash a single block of memory without the overhead of
   creating an encryption context.  This always uses SHA1 */

void shaHashBuffer( HASHINFO hashInfo, BYTE *outBuffer, 
                    const int outBufMaxLength, const void *inBuffer, 
                    const int inLength, const HASH_STATE hashState )
    {
    SHA_CTX *shaInfo = ( SHA_CTX * ) hashInfo;

    assert( isWritePtr( hashInfo, sizeof( HASHINFO ) ) );
    assert( ( hashState != HASH_STATE_END && \
              outBuffer == NULL && outBufMaxLength == 0 ) || \
            ( hashState == HASH_STATE_END && \
              isWritePtr( outBuffer, outBufMaxLength ) && \
              outBufMaxLength >= 20 ) );
    assert( inBuffer == NULL || isReadPtr( inBuffer, inLength ) );

    if( ( hashState == HASH_STATE_END && outBufMaxLength < 20 ) || \
        ( hashState != HASH_STATE_END && inLength <= 0 ) )
        retIntError_Void();

    switch( hashState )
        {
        case HASH_STATE_START:
            SHA1_Init( shaInfo );
            /* Drop through */

        case HASH_STATE_CONTINUE:
            SHA1_Update( shaInfo, ( BYTE * ) inBuffer, inLength );
            break;

        case HASH_STATE_END:
            if( inBuffer != NULL )
                SHA1_Update( shaInfo, ( BYTE * ) inBuffer, inLength );
            SHA1_Final( outBuffer, shaInfo );
            break;

        default:
            retIntError_Void();
        }
    }

void shaHashBufferAtomic( BYTE *outBuffer, const int outBufMaxLength, 
                          const void *inBuffer, const int inLength )
    {
    SHA_CTX shaInfo;

    assert( isWritePtr( outBuffer, outBufMaxLength ) && \
            outBufMaxLength >= 20 );
    assert( isReadPtr( inBuffer, inLength ) );

    if( outBufMaxLength < 20 || inLength <= 0 )
        retIntError_Void();

    SHA1_Init( &shaInfo );
    SHA1_Update( &shaInfo, ( BYTE * ) inBuffer, inLength );
    SHA1_Final( outBuffer, &shaInfo );
    zeroise( &shaInfo, sizeof( SHA_CTX ) );
    }

/****************************************************************************
*                                                                           *
*                       Capability Access Routines                          *
*                                                                           *
****************************************************************************/

static const CAPABILITY_INFO FAR_BSS capabilityInfo = {
    CRYPT_ALGO_SHA1, bitsToBytes( 160 ), "SHA-1", 5,
    bitsToBytes( 0 ), bitsToBytes( 0 ), bitsToBytes( 0 ),
    selfTest, getInfo, NULL, NULL, NULL, NULL, hash, hash
    };

const CAPABILITY_INFO *getSHA1Capability( void )
    {
    return( &capabilityInfo );
    }