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Alphabetical listing for D

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dsa(3)
NAME
  dsa - Digital Signature Algorithm

SYNOPSIS
  #include <openssl/dsa.h>
  #include <openssl/engine.h>

  DSA * DSA_new(
	  void );

  void DSA_free(
	  DSA *dsa );

  int DSA_size(
	  DSA *dsa );

  DSA * DSA_generate_parameters(
	  int bits,
	  unsigned char *seed,
	  int seed_len,
	  int *counter_ret,
	  unsigned long *h_ret,
	  void (*callback)(int, int, void*),
	  void *cb_arg );

  DH * DSA_dup_DH(
	  DSA *r );

  int	   DSA_generate_key(
	  DSA *dsa );

  int	   DSA_sign(
	  int dummy,
	  const unsigned char *dgst,
	  int len,
	  unsigned char *sigret,
	  unsigned int *siglen,
	  DSA *dsa );

  int	   DSA_sign_setup(
	  DSA *dsa,
	  BN_CTX *ctx,
	  BIGNUM **kinvp,
	  BIGNUM **rp );

  int	   DSA_verify(
	  int dummy,
	  const unsigned char *dgst,
	  int len,
	  unsigned char *sigbuf,
	  int siglen,
	  DSA *dsa );

  void DSA_set_default_openssl_method(
	  DSA_METHOD *meth );

  DSA_METHOD *DSA_get_default_openssl_method(
	  void );

  int DSA_set_method(
	  DSA *dsa,
	  ENGINE *engine );

  DSA *DSA_new_method(
	  ENGINE *engine );

  DSA_METHOD *DSA_OpenSSL(
	  void );

  int DSA_get_ex_new_index(
	  long argl,
	  char *argp,
	  int (*new_func)(),
	  int (*dup_func)(),
	  void (*free_func)() );

  int DSA_set_ex_data(
	  DSA *d,
	  int idx,
	  char *arg );

  char *DSA_get_ex_data(
	  DSA *d,
	  int idx );

  DSA_SIG *DSA_SIG_new(
	  void );

  void	  DSA_SIG_free(
	  DSA_SIG *a );

  int	   i2d_DSA_SIG(
	  DSA_SIG *a,
	  unsigned char **pp );

  DSA_SIG *d2i_DSA_SIG(
	  DSA_SIG **v,
	  unsigned char **pp,
	  long length );

  DSA_SIG *DSA_do_sign(
	  const unsigned char *dgst,
	  int dlen,
	  DSA *dsa );

  int	   DSA_do_verify(
	  const unsigned char *dgst,
	  int dgst_len,
	  DSA_SIG *sig,
	  DSA *dsa );

  DSA * d2i_DSAPublicKey(
	  DSA **a,
	  unsigned char **pp,
	  long length );

  DSA *	  d2i_DSAPrivateKey(
	  DSA **a,
	  unsigned char **pp,
	  long length );

  DSA * d2i_DSAparams(
	  DSA **a,
	  unsigned char **pp,
	  long length );

  int	   i2d_DSAPublicKey(
	  DSA *a,
	  unsigned char **pp );

  int	   i2d_DSAPrivateKey(
	  DSA *a,
	  unsigned char **pp );

  int	   i2d_DSAparams(
	  DSA *a,
	  unsigned char **pp );

  int	   DSAparams_print(
	  BIO *bp,
	  DSA *x );

  int	   DSAparams_print_fp(
	  FILE *fp,
	  DSA *x );

  int	   DSA_print(
	  BIO *bp,
	  DSA *x,
	  int off );

  int	   DSA_print_fp(
	  FILE *bp,
	  DSA *x,
	  int off );

DESCRIPTION
  These functions implement the Digital Signature Algorithm (DSA).  The
  generation of shared DSA parameters is described in
  DSA_generate_parameters(3); DSA_generate_key(3) describes how to generate a
  signature key. Signature generation and verification are described in
  DSA_sign(3).

  The DSA structure consists of several BIGNUM components.

	struct
	       {
	       BIGNUM *p;	       // prime number (public)
	       BIGNUM *q;	       // 160-bit subprime, q | p-1 (public)
	       BIGNUM *g;	       // generator of subgroup (public)
	       BIGNUM *priv_key;       // private key x
	       BIGNUM *pub_key;	       // public key y = g^x
	       // ...
	       }
	DSA;

  In public keys, priv_key is NULL.

  DSA conforms to US Federal Information Processing Standard FIPS 186
  (Digital Signature Standard, DSS), ANSI X9.30

SEE ALSO
  Functions: bn(3), dh(3), err(3), rand_ssl(3), rsa(3), sha(3), DSA_new(3),
  DSA_size(3), DSA_generate_parameters(3), DSA_dup_DH(3),
  DSA_generate_key(3), DSA_sign(3), DSA_set_method(3),
  DSA_get_ex_new_index(3), RSA_print(3)

Index for Section 3

Alphabetical listing for D

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