X-Git-Url: https://git.distorted.org.uk/u/mdw/catacomb/blobdiff_plain/8b810a45dec25017a6256e4ef134236444a00921..f41f820e4b3e230d9314cc4323abf59babdd4e67:/dsa.h diff --git a/dsa.h b/dsa.h index 1958d50..2b4949d 100644 --- a/dsa.h +++ b/dsa.h @@ -1,6 +1,6 @@ /* -*-c-*- * - * $Id: dsa.h,v 1.1 1999/11/19 19:28:00 mdw Exp $ + * $Id: dsa.h,v 1.6 2000/07/01 11:20:51 mdw Exp $ * * Digital Signature Algorithm * @@ -30,13 +30,28 @@ /*----- Revision history --------------------------------------------------* * * $Log: dsa.h,v $ + * Revision 1.6 2000/07/01 11:20:51 mdw + * New functions for freeing public and private keys. + * + * Revision 1.5 2000/06/17 10:53:42 mdw + * Minor changes for key fetching. Typesetting fixes. + * + * Revision 1.4 1999/12/22 15:52:44 mdw + * Reworking for new prime-search system. + * + * Revision 1.3 1999/12/10 23:29:48 mdw + * Change header file guard names. + * + * Revision 1.2 1999/11/20 22:23:48 mdw + * Allow event handler to abort the search process. + * * Revision 1.1 1999/11/19 19:28:00 mdw * Implementation of the Digital Signature Algorithm. * */ -#ifndef DSA_H -#define DSA_H +#ifndef CATACOMB_DSA_H +#define CATACOMB_DSA_H #ifdef __cplusplus extern "C" { @@ -53,28 +68,17 @@ /*----- Header files ------------------------------------------------------*/ -#ifndef MP_H -# include "mp.h" +#ifndef CATACOMB_KEY_H +# include "key.h" #endif -/*----- Event codes -------------------------------------------------------*/ - -enum { - DSAEV_OK, /* Everything is fine */ - - DSAEV_FAILQ, /* @q@ failed primality test */ - DSAEV_PASSQ, /* @q@ passeed one iteration */ - DSAEV_GOODQ, /* Found good prime @q@ */ - - DSAEV_TRYP, /* Try prospective @p@ */ - DSAEV_FAILP, /* @p@ failed primality test */ - DSAEV_PASSP, /* @p@ passed one iteration */ - DSAEV_GOODP, /* @p@ accepted as being prime */ - - DSAEV_TRYH, /* Try prospective @h@ */ - DSAEV_FAILH, /* @h@ failed */ - DSAEV_GOODG /* @g@ accepted as a generator */ -}; +#ifndef CATACOMB_MP_H +# include "mp.h" +#endif + +#ifndef CATACOMB_PGEN_H +# include "pgen.h" +#endif /*----- Data structures ---------------------------------------------------*/ @@ -89,6 +93,17 @@ typedef struct dsa_param { mp *g; /* Generates order-%$q$% subgroup */ } dsa_param; +typedef struct dsa_pub { + dsa_param dp; /* Shared parameters */ + mp *y; /* Public key */ +} dsa_pub; + +typedef struct dsa_priv { + dsa_param dp; /* Shared parameters */ + mp *x; /* Private key */ + mp *y; /* %$y \equiv g^x \pmod{p}$% */ +} dsa_priv; + /* --- DSA signature structure --- * * * This is the recommended structure for a DSA signature. The actual signing @@ -103,43 +118,87 @@ typedef struct dsa_sig { octet s[DSA_SIGLEN]; /* 160-bit @s@ value */ } dsa_sig; +/*----- Key fetching ------------------------------------------------------*/ + +extern const key_fetchdef dsa_paramfetch[]; +#define DSA_PARAMFETCHSZ 5 + +extern const key_fetchdef dsa_pubfetch[]; +#define DSA_PUBFETCHSZ 6 + +extern const key_fetchdef dsa_privfetch[]; +#define DSA_PRIVFETCHSZ 9 + +/* --- @dsa_paramfree@, @dsa_pubfree@, @dsa_privfree@ --- * + * + * Arguments: @dsa_param *dp@, @dsa_pub *dp@, @dsa_priv *dp@ = pointer + * to key block to free + * + * Returns: --- + * + * Use: Frees a DSA key block. + */ + +extern void dsa_paramfree(dsa_param */*dp*/); +extern void dsa_pubfree(dsa_pub */*dp*/); +extern void dsa_privfree(dsa_priv */*dp*/); + +/*----- DSA stepper -------------------------------------------------------*/ + +typedef struct dsa_stepctx { + + /* --- To be initialized by the client --- */ + + grand *r; /* Random number generator */ + mp *q; /* Force @p@ to be a multiple */ + size_t bits; /* Number of bits in the result */ + unsigned or; /* OR mask for low order bits */ +} dsa_stepctx; + +/* --- @dsa_step@ --- * + * + * The stepper chooses random integers, ensures that they are a multiple of + * @q@ (if specified), sets the low-order bits, and then tests for + * divisibility by small primes. + */ + +extern int dsa_step(int /*rq*/, pgen_event */*ev*/, void */*p*/); + /*----- Functions provided ------------------------------------------------*/ /* --- @dsa_seed@ --- * * * Arguments: @dsa_param *dp@ = where to store parameters - * @unsigned l@ = bitlength of @p@ in bits + * @unsigned ql@ = length of @q@ in bits + * @unsigned pl@ = length of @p@ in bits + * @unsigned steps@ = number of steps to find @q@ * @const void *k@ = pointer to key material * @size_t sz@ = size of key material - * @void (*proc)(int ev, mp *m, void *p)@ = event procedure - * @void *p@ = argument for event procedure + * @pgen_proc *event@ = event handler function + * @void *ectx@ = argument for event handler * - * Returns: Zero if all went well, nonzero if key material was - * unsuitable (one of the @DSAEV@ codes). + * Returns: @PGEN_DONE@ if everything worked ok; @PGEN_ABORT@ otherwise. * * Use: Generates the DSA shared parameters from a given seed value. - * This can take quite a long time. The size of @p@ in bits is - * %$l = 512 + 64l'$%. The DSA standard, FIPS 186, only allows - * %$0 \le l' \le 8$%. This implementation has no such limit, - * although @l@ must be a multiple of 8. - * - * The event procedure is informed of various happenings during - * generation. It is passed an event code describing what - * happened, and a multiprecision number which pertains to the - * event code. + * This can take quite a long time. + * + * The algorithm used is a compatible extension of the method + * described in the DSA standard, FIPS 186. The standard + * requires that %$q$% be 160 bits in size (i.e., @ql == 160@) + * and that the length of %$p$% be %$L = 512 + 64l$% for some + * %$l$%. Neither limitation applies to this implementation. */ -extern int dsa_seed(dsa_param */*dp*/, unsigned /*l*/, - const void */*k*/, size_t /*sz*/, - void (*proc)(int /*ev*/, mp */*m*/, void */*p*/), - void */*p*/); +extern int dsa_seed(dsa_param */*dp*/, unsigned /*ql*/, unsigned /*pl*/, + unsigned /*steps*/, const void */*k*/, size_t /*sz*/, + pgen_proc */*event*/, void */*ectx*/); /* --- @dsa_mksig@ --- * * * Arguments: @const dsa_param *dp@ = pointer to DSA parameters - * @const mp *a@ = secret signing key - * @const mp *m@ = message to be signed - * @const mp *k@ = random data + * @mp *a@ = secret signing key + * @mp *m@ = message to be signed + * @mp *k@ = random data * @mp **rr, **ss@ = where to put output parameters * * Returns: --- @@ -147,8 +206,8 @@ extern int dsa_seed(dsa_param */*dp*/, unsigned /*l*/, * Use: Computes a DSA signature of a message. */ -extern void dsa_mksig(const dsa_param */*dp*/, const mp */*a*/, - const mp */*m*/, const mp */*k*/, +extern void dsa_mksig(const dsa_param */*dp*/, mp */*a*/, + mp */*m*/, mp */*k*/, mp **/*rr*/, mp **/*ss*/); /* --- @dsa_sign@ --- * @@ -179,22 +238,22 @@ extern void dsa_sign(dsa_param */*dp*/, mp */*a*/, /* --- @dsa_vrfy@ --- * * * Arguments: @const dsa_param *dp@ = pointer to DSA parameters - * @const mp *y@ = public verification key - * @const mp *m@ = message which was signed - * @const mp *r, *s@ = the signature + * @mp *y@ = public verification key + * @mp *m@ = message which was signed + * @mp *r, *s@ = the signature * * Returns: Zero if the signature is a forgery, nonzero if it's valid. * * Use: Verifies a DSA digital signature. */ -extern int dsa_vrfy(const dsa_param */*dp*/, const mp */*y*/, - const mp */*m*/, const mp */*r*/, const mp */*s*/); +extern int dsa_vrfy(const dsa_param */*dp*/, mp */*y*/, + mp */*m*/, mp */*r*/, mp */*s*/); /* --- @dsa_verify@ --- * * * Arguments: @const dsa_param *dp@ = pointer to DSA parameters - * @const mp *y@ = public verification key + * @mp *y@ = public verification key * @const void *m@ = pointer to message block * @size_t msz@ = size of message block * @const void *r@ = pointer to @r@ signature half @@ -207,10 +266,10 @@ extern int dsa_vrfy(const dsa_param */*dp*/, const mp */*y*/, * Use: Verifies a DSA digital signature. */ -extern int dsa_verify(const dsa_param */*dp*/, const mp */*y*/, - const void */*m*/, size_t /*msz*/, - const void */*r*/, size_t /*rsz*/, - const void */*s*/, size_t /*ssz*/); +extern int dsa_verify(const dsa_param */*dp*/, mp */*y*/, + const void */*m*/, size_t /*msz*/, + const void */*r*/, size_t /*rsz*/, + const void */*s*/, size_t /*ssz*/); /*----- That's all, folks -------------------------------------------------*/