sha256.h File Reference

SHA-256 algorithm. More...

#include <stdint.h>
#include <ipxe/crypto.h>

Go to the source code of this file.

Data Structures
struct	sha256_digest
	An SHA-256 digest. More...
union	sha256_block
	An SHA-256 data block. More...
struct	sha256_digest_data
	SHA-256 digest and data block. More...
union	sha256_digest_data_dwords
	SHA-256 digest and data block. More...
struct	sha256_context
	An SHA-256 context. More...

Macros
#define	SHA256_ROUNDS   64
	SHA-256 number of rounds. More...
#define	SHA256_CTX_SIZE   sizeof ( struct sha256_context )
	SHA-256 context size. More...
#define	SHA256_BLOCK_SIZE   sizeof ( union sha256_block )
	SHA-256 block size. More...
#define	SHA256_DIGEST_SIZE   sizeof ( struct sha256_digest )
	SHA-256 digest size. More...
#define	SHA224_DIGEST_SIZE   ( SHA256_DIGEST_SIZE * 224 / 256 )
	SHA-224 digest size. More...

Functions
	FILE_LICENCE (GPL2_OR_LATER_OR_UBDL)
void	sha256_family_init (struct sha256_context *context, const struct sha256_digest *init, size_t digestsize)
	Initialise SHA-256 family algorithm. More...
void	sha256_update (void *ctx, const void *data, size_t len)
	Accumulate data with SHA-256 algorithm. More...
void	sha256_final (void *ctx, void *out)
	Generate SHA-256 digest. More...

Variables
struct digest_algorithm	sha256_algorithm
	SHA-256 algorithm. More...
struct digest_algorithm	sha224_algorithm
	SHA-224 algorithm. More...

Detailed Description

SHA-256 algorithm.

Definition in file sha256.h.

Macro Definition Documentation

SHA256_ROUNDS

#define SHA256_ROUNDS   64

SHA-256 number of rounds.

Definition at line 16 of file sha256.h.

SHA256_CTX_SIZE

#define SHA256_CTX_SIZE   sizeof ( struct sha256_context )

SHA-256 context size.

Definition at line 71 of file sha256.h.

SHA256_BLOCK_SIZE

#define SHA256_BLOCK_SIZE   sizeof ( union sha256_block )

SHA-256 block size.

Definition at line 74 of file sha256.h.

SHA256_DIGEST_SIZE

#define SHA256_DIGEST_SIZE   sizeof ( struct sha256_digest )

SHA-256 digest size.

Definition at line 77 of file sha256.h.

SHA224_DIGEST_SIZE

#define SHA224_DIGEST_SIZE   ( SHA256_DIGEST_SIZE * 224 / 256 )

SHA-224 digest size.

Definition at line 80 of file sha256.h.

Function Documentation

FILE_LICENCE()

FILE_LICENCE

(

GPL2_OR_LATER_OR_UBDL

)

sha256_family_init()

void sha256_family_init	(	struct sha256_context *	context,
		const struct sha256_digest *	init,
		size_t	digestsize
	)

Initialise SHA-256 family algorithm.

Parameters

context	SHA-256 context
init	Initial digest values
digestsize	Digest size

Definition at line 92 of file sha256.c.

                                              {

        context->len = 0;
        context->digestsize = digestsize;
        memcpy ( &context->ddd.dd.digest, init,
                 sizeof ( context->ddd.dd.digest ) );
}

References sha256_digest_data_dwords::dd, sha256_context::ddd, sha256_digest_data::digest, digestsize, sha256_context::digestsize, sha256_context::len, and memcpy().

Referenced by sha224_init(), and sha256_init().

sha256_update()

void sha256_update	(	void *	ctx,
		const void *	data,
		size_t	len
	)

Accumulate data with SHA-256 algorithm.

Parameters

ctx	SHA-256 context
data	Data
len	Length of data

Definition at line 216 of file sha256.c.

                                                               {
        struct sha256_context *context = ctx;
        const uint8_t *byte = data;
        size_t offset;

        /* Accumulate data a byte at a time, performing the digest
         * whenever we fill the data buffer
         */
        while ( len-- ) {
                offset = ( context->len % sizeof ( context->ddd.dd.data ) );
                context->ddd.dd.data.byte[offset] = *(byte++);
                context->len++;
                if ( ( context->len % sizeof ( context->ddd.dd.data ) ) == 0 )
                        sha256_digest ( context );
        }
}

References sha256_block::byte, ctx, data, sha256_digest_data::data, sha256_digest_data_dwords::dd, sha256_context::ddd, sha256_context::len, len, offset, and sha256_digest().

Referenced by sha256_final().

sha256_final()

void sha256_final	(	void *	ctx,
		void *	out
	)

Generate SHA-256 digest.

Parameters

ctx	SHA-256 context
out	Output buffer

Definition at line 239 of file sha256.c.

                                           {
        struct sha256_context *context = ctx;
        uint64_t len_bits;
        uint8_t pad;

        /* Record length before pre-processing */
        len_bits = cpu_to_be64 ( ( ( uint64_t ) context->len ) * 8 );

        /* Pad with a single "1" bit followed by as many "0" bits as required */
        pad = 0x80;
        do {
                sha256_update ( ctx, &pad, sizeof ( pad ) );
                pad = 0x00;
        } while ( ( context->len % sizeof ( context->ddd.dd.data ) ) !=
                  offsetof ( typeof ( context->ddd.dd.data ), final.len ) );

        /* Append length (in bits) */
        sha256_update ( ctx, &len_bits, sizeof ( len_bits ) );
        assert ( ( context->len % sizeof ( context->ddd.dd.data ) ) == 0 );

        /* Copy out final digest */
        memcpy ( out, &context->ddd.dd.digest, context->digestsize );
}

References assert(), cpu_to_be64, ctx, sha256_digest_data::data, sha256_digest_data_dwords::dd, sha256_context::ddd, sha256_digest_data::digest, sha256_context::digestsize, sha256_context::len, memcpy(), offsetof, out, pad, sha256_update(), and typeof().

Variable Documentation

sha256_algorithm

struct digest_algorithm sha256_algorithm

SHA-256 algorithm.

Definition at line 264 of file sha256.c.

Referenced by icert_cert(), peerdist_info_v1(), sha256_test_exec(), and sha256sum_exec().

sha224_algorithm

struct digest_algorithm sha224_algorithm

SHA-224 algorithm.

Definition at line 63 of file sha224.c.

Referenced by sha224sum_exec(), and sha256_test_exec().