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dsa.h File Reference

Digital Signature Algorithm, as specified by NIST FIPS 186. More...

#include "dlkp.h"

Go to the source code of this file.

Typedefs

typedef dldp_p dsaparam
typedef dlpk_p dsapub
typedef dlkp_p dsakp

Functions

int dsasign (const mpbarrett *p, const mpbarrett *q, const mpnumber *g, randomGeneratorContext *, const mpnumber *hm, const mpnumber *x, mpnumber *r, mpnumber *s)
 This function performs a raw DSA signature.
int dsavrfy (const mpbarrett *p, const mpbarrett *q, const mpnumber *g, const mpnumber *hm, const mpnumber *y, const mpnumber *r, const mpnumber *s)
 This function performs a raw DSA verification.

Detailed Description

Digital Signature Algorithm, as specified by NIST FIPS 186.

FIPS 186 specifies the DSA algorithm as having a large prime $p$, a cofactor $q$ and a generator $g$ of a subgroup of $\mathds{Z}^{*}_p$ with order $q$. The private and public key values are $x$ and $y$ respectively.

Author:
Bob Deblier <bob.deblier@pandora.be>

Definition in file dsa.h.

Typedef Documentation

typedef dlkp_p dsakp
 

Definition at line 39 of file dsa.h.

typedef dldp_p dsaparam
 

Definition at line 37 of file dsa.h.

typedef dlpk_p dsapub
 

Definition at line 38 of file dsa.h.

Function Documentation

int dsasign (  const mpbarrett *  p,
const mpbarrett *  q,
const mpnumber *  g,
randomGeneratorContext *  rgc,
const mpnumber *  hm,
const mpnumber *  x,
mpnumber *  r,
mpnumber *  s
) 
 

This function performs a raw DSA signature.

Signing equations:

  • $r=(g^{k}\ \textrm{mod}\ p)\ \textrm{mod}\ q$
  • $s=k^{-1}(h(m)+xr)\ \textrm{mod}\ q$
Parameters:
p The prime.
q The cofactor.
g The generator.
rgc The pseudo-random generator context.
hm The hash to be signed.
x The private key value.
r The signature's r value.
s The signature's s value.
Return values:
0 on success.
-1 on failure.

int dsavrfy (  const mpbarrett *  p,
const mpbarrett *  q,
const mpnumber *  g,
const mpnumber *  hm,
const mpnumber *  y,
const mpnumber *  r,
const mpnumber *  s
) 
 

This function performs a raw DSA verification.

Verifying equations:

  • Check $0<r<q$ and $0<s<q$
  • $w=s^{-1}\ \textrm{mod}\ q$
  • $u_1=w \cdot h(m)\ \textrm{mod}\ q$
  • $u_2=rw\ \textrm{mod}\ q$
  • $v=(g^{u_1}y^{u_2}\ \textrm{mod}\ p)\ \textrm{mod}\ q$
  • Check $v=r$
Parameters:
p The prime.
q The cofactor.
g The generator.
hm The digest to be verified.
y The public key value.
r The signature's r value.
s The signature's s value.
Return values:
1 on success.
0 on failure.

Generated on Fri Feb 18 01:31:25 2005 for BeeCrypt by  doxygen 1.3.9.1