dhm.c File Reference

#include "polarssl/config.h"
#include "polarssl/dhm.h"
#include "polarssl/pem.h"
#include "polarssl/asn1.h"
#include <stdlib.h>
#include "polarssl/certs.h"

Include dependency graph for dhm.c:

Go to the source code of this file.

Defines
#define	polarssl_malloc malloc
#define	polarssl_free free
#define	DHM_MPI_EXPORT(X, n)
Functions
static int	dhm_read_bignum (mpi X, unsigned char p, const unsigned char end)
static int	dhm_check_range (const mpi param, const mpi P)
int	dhm_read_params (dhm_context ctx, unsigned char p, const unsigned char end)
	Parse the ServerKeyExchange parameters.
int	dhm_make_params (dhm_context ctx, int x_size, unsigned char output, size_t olen, int(f_rng)(void , unsigned char , size_t), void *p_rng)
	Setup and write the ServerKeyExchange parameters.
int	dhm_read_public (dhm_context ctx, const unsigned char input, size_t ilen)
	Import the peer's public value G^Y.
int	dhm_make_public (dhm_context ctx, int x_size, unsigned char output, size_t olen, int(f_rng)(void , unsigned char , size_t), void p_rng)
	Create own private value X and export G^X.
static int	dhm_update_blinding (dhm_context ctx, int(f_rng)(void , unsigned char , size_t), void *p_rng)
int	dhm_calc_secret (dhm_context ctx, unsigned char output, size_t olen, int(f_rng)(void , unsigned char , size_t), void *p_rng)
	Derive and export the shared secret (G^Y)^X mod P.
void	dhm_free (dhm_context *ctx)
	Free the components of a DHM key.
int	dhm_parse_dhm (dhm_context dhm, const unsigned char dhmin, size_t dhminlen)
	Parse DHM parameters.
static int	load_file (const char path, unsigned char buf, size_t n)
int	dhm_parse_dhmfile (dhm_context dhm, const char path)
	Load and parse DHM parameters.
int	dhm_self_test (int verbose)
	Checkup routine.

Define Documentation

#define DHM_MPI_EXPORT	(	X,
		n		)

Value:

MPI_CHK( mpi_write_binary( X, p + 2, n ) ); \
    *p++ = (unsigned char)( n >> 8 );           \
    *p++ = (unsigned char)( n      ); p += n;

Referenced by dhm_make_params().

#define polarssl_free free

Definition at line 50 of file dhm.c.

#define polarssl_malloc malloc

Definition at line 49 of file dhm.c.

Function Documentation

int dhm_calc_secret	(	dhm_context *	ctx,
		unsigned char *	output,
		size_t *	olen,
		int()(void , unsigned char *, size_t)	f_rng,
		void *	p_rng
	)

Derive and export the shared secret (G^Y)^X mod P.

Parameters:

	ctx	DHM context
	output	destination buffer
	olen	number of chars written
	f_rng	RNG function, for blinding purposes
	p_rng	RNG parameter

Returns:: 0 if successful, or an POLARSSL_ERR_DHM_XXX error code

Note:: If non-NULL, f_rng is used to blind the input as countermeasure against timing attacks. Blinding is automatically used if and only if our secret value X is re-used and costs nothing otherwise, so it is recommended to always pass a non-NULL f_rng argument.

Definition at line 332 of file dhm.c.

References dhm_check_range(), dhm_update_blinding(), dhm_context::GY, dhm_context::K, MPI_CHK, mpi_copy(), mpi_exp_mod(), mpi_free(), mpi_init(), mpi_mod_mpi(), mpi_mul_mpi(), mpi_size(), mpi_write_binary(), dhm_context::P, POLARSSL_ERR_DHM_BAD_INPUT_DATA, POLARSSL_ERR_DHM_CALC_SECRET_FAILED, dhm_context::RP, dhm_context::Vf, dhm_context::Vi, and dhm_context::X.

Referenced by ssl_parse_client_key_exchange(), ssl_psk_derive_premaster(), and ssl_write_client_key_exchange().

static int dhm_check_range	(	const mpi *	param,
		const mpi *	P
	)			`[static]`

Definition at line 88 of file dhm.c.

References mpi_cmp_mpi(), mpi_free(), mpi_init(), mpi_lset(), mpi_sub_int(), and POLARSSL_ERR_DHM_BAD_INPUT_DATA.

Referenced by dhm_calc_secret(), dhm_make_params(), dhm_make_public(), and dhm_read_params().

void dhm_free ( dhm_context * ctx )

Free the components of a DHM key.

Definition at line 385 of file dhm.c.

References dhm_context::G, dhm_context::GX, dhm_context::GY, dhm_context::K, mpi_free(), dhm_context::P, dhm_context::pX, dhm_context::RP, dhm_context::Vf, dhm_context::Vi, and dhm_context::X.

Referenced by dhm_parse_dhm(), dhm_read_params(), dhm_self_test(), and ssl_handshake_free().

int dhm_make_params	(	dhm_context *	ctx,
		int	x_size,
		unsigned char *	output,
		size_t *	olen,
		int()(void , unsigned char *, size_t)	f_rng,
		void *	p_rng
	)

Setup and write the ServerKeyExchange parameters.

Parameters:

	ctx	DHM context
	x_size	private value size in bytes
	output	destination buffer
	olen	number of chars written
	f_rng	RNG function
	p_rng	RNG parameter

Note:: This function assumes that ctx->P and ctx->G have already been properly set (for example using mpi_read_string or mpi_read_binary).

Returns:: 0 if successful, or an POLARSSL_ERR_DHM_XXX error code

Definition at line 135 of file dhm.c.

References dhm_check_range(), DHM_MPI_EXPORT, dhm_context::G, dhm_context::GX, dhm_context::len, MPI_CHK, mpi_cmp_int(), mpi_cmp_mpi(), mpi_exp_mod(), mpi_fill_random(), mpi_shift_r(), mpi_size(), dhm_context::P, POLARSSL_ERR_DHM_BAD_INPUT_DATA, POLARSSL_ERR_DHM_MAKE_PARAMS_FAILED, dhm_context::RP, and dhm_context::X.

Referenced by ssl_write_server_key_exchange().

int dhm_make_public	(	dhm_context *	ctx,
		int	x_size,
		unsigned char *	output,
		size_t	olen,
		int()(void , unsigned char *, size_t)	f_rng,
		void *	p_rng
	)

Create own private value X and export G^X.

Parameters:

	ctx	DHM context
	x_size	private value size in bytes
	output	destination buffer
	olen	must be equal to ctx->P.len
	f_rng	RNG function
	p_rng	RNG parameter

Returns:: 0 if successful, or an POLARSSL_ERR_DHM_XXX error code

Definition at line 220 of file dhm.c.

References dhm_check_range(), dhm_context::G, dhm_context::GX, dhm_context::len, MPI_CHK, mpi_cmp_int(), mpi_cmp_mpi(), mpi_exp_mod(), mpi_fill_random(), mpi_shift_r(), mpi_write_binary(), dhm_context::P, POLARSSL_ERR_DHM_BAD_INPUT_DATA, POLARSSL_ERR_DHM_MAKE_PUBLIC_FAILED, dhm_context::RP, and dhm_context::X.

Referenced by ssl_write_client_key_exchange().

static int dhm_read_bignum	(	mpi *	X,
		unsigned char **	p,
		const unsigned char *	end
	)			`[static]`

Definition at line 56 of file dhm.c.

References mpi_read_binary(), POLARSSL_ERR_DHM_BAD_INPUT_DATA, and POLARSSL_ERR_DHM_READ_PARAMS_FAILED.

Referenced by dhm_read_params().

int dhm_read_params	(	dhm_context *	ctx,
		unsigned char **	p,
		const unsigned char *	end
	)

Parse the ServerKeyExchange parameters.

Parameters:

	ctx	DHM context
	p	&(start of input buffer)
	end	end of buffer

Returns:: 0 if successful, or an POLARSSL_ERR_DHM_XXX error code

Definition at line 111 of file dhm.c.

References dhm_check_range(), dhm_free(), dhm_read_bignum(), dhm_context::G, dhm_context::GY, dhm_context::len, mpi_size(), and dhm_context::P.

Referenced by ssl_parse_server_dh_params().

int dhm_read_public	(	dhm_context *	ctx,
		const unsigned char *	input,
		size_t	ilen
	)

Import the peer's public value G^Y.

Parameters:

	ctx	DHM context
	input	input buffer
	ilen	size of buffer

Returns:: 0 if successful, or an POLARSSL_ERR_DHM_XXX error code

Definition at line 203 of file dhm.c.

References dhm_context::GY, dhm_context::len, mpi_read_binary(), POLARSSL_ERR_DHM_BAD_INPUT_DATA, and POLARSSL_ERR_DHM_READ_PUBLIC_FAILED.

Referenced by ssl_parse_client_dh_public().

int dhm_self_test ( int verbose )

Checkup routine.

Returns:: 0 if successful, or 1 if the test failed

Definition at line 544 of file dhm.c.

References dhm_free(), dhm_parse_dhm(), POLARSSL_ERR_X509_FEATURE_UNAVAILABLE, and test_dhm_params.

static int dhm_update_blinding	(	dhm_context *	ctx,
		int()(void , unsigned char *, size_t)	f_rng,
		void *	p_rng
	)			`[static]`

Definition at line 270 of file dhm.c.

References MPI_CHK, mpi_cmp_int(), mpi_cmp_mpi(), mpi_copy(), mpi_exp_mod(), mpi_fill_random(), mpi_inv_mod(), mpi_lset(), mpi_mod_mpi(), mpi_mul_mpi(), mpi_shift_r(), mpi_size(), dhm_context::P, POLARSSL_ERR_MPI_NOT_ACCEPTABLE, dhm_context::pX, dhm_context::RP, dhm_context::Vf, dhm_context::Vi, and dhm_context::X.

Referenced by dhm_calc_secret().

static int load_file	(	const char *	path,
		unsigned char **	buf,
		size_t *	n
	)			`[static]`

Definition at line 476 of file dhm.c.

References POLARSSL_ERR_DHM_FILE_IO_ERROR, POLARSSL_ERR_DHM_MALLOC_FAILED, polarssl_free, and polarssl_malloc.

Referenced by dhm_parse_dhmfile().

dhm.c File Reference

Defines

Functions

Define Documentation

Function Documentation