#include "xs/openssl.h"


MODULE = Crypt::Keyczar		PACKAGE = Crypt::Keyczar::DsaPublicKeyEngine

Crypt::Keyczar::DsaPublicKeyEngine
new(class, y, p, q, g)
	SV *class
	SV *y
	SV *p
	SV *q
	SV *g
	CODE:
	{
	    DSA *dsa;
	    STRLEN l;
	    unsigned char *in;
	    BIGNUM *bp, *bq, *bg, *pub_key;

	    PERL_UNUSED_VAR(class);

	    if ((dsa = DSA_new()) == NULL) {
	        crypt__keyczar__util__croak_openssl();
	        /* NOTREACHED */
	    }
	    in = (unsigned char *)SvPV(p, l);
	    bp = BN_bin2bn((const unsigned char *)in, l, NULL);
	    if (bp == NULL) {
	        DSA_free(dsa);
	        crypt__keyczar__util__croak_openssl();
	        /* NOTREACHED */
	    }
	    in = (unsigned char *)SvPV(q, l);
	    bq = BN_bin2bn((const unsigned char *)in, l, NULL);
	    if (bq == NULL) {
	        DSA_free(dsa);
	        crypt__keyczar__util__croak_openssl();
	        /* NOTREACHED */
	    }
	    in = (unsigned char *)SvPV(g, l);
	    bg = BN_bin2bn((const unsigned char *)in, l, NULL);
	    if (bg == NULL) {
	        DSA_free(dsa);
	        crypt__keyczar__util__croak_openssl();
	        /* NOTREACHED */
	    }
	    DSA_set0_pqg(dsa, bp, bq, bg);

	    in = (unsigned char *)SvPV(y, l);
	    pub_key = BN_bin2bn((const unsigned char *)in, l, NULL);
	    if (pub_key == NULL) {
	        DSA_free(dsa);
	        crypt__keyczar__util__croak_openssl();
	        /* NOTREACHED */
	    }
	    DSA_set0_key(dsa, pub_key, NULL);

	    Newz(0, RETVAL, 1, struct Crypt__Keyczar__DsaPublicKeyEngine_class);
	    RETVAL->dsa = dsa;
	}
	OUTPUT:
	    RETVAL


void
DESTROY(self)
	Crypt::Keyczar::DsaPublicKeyEngine self
	CODE:
	{
	    if (self->dsa != NULL) {
	        DSA_free(self->dsa);
	        self->dsa = NULL;
	    }
	    Safefree(self);
	}


SV *
init(self, ...)
	Crypt::Keyczar::DsaPublicKeyEngine self
	CODE:
	{
	    RETVAL = newSVpv("", 0);
	}
	OUTPUT:
	    RETVAL


void
update(self, ...)
	Crypt::Keyczar::DsaPublicKeyEngine self
	CODE:
	{
	    int i;
	    SV *data;
	    STRLEN l;
	    unsigned char *in;

	    if (self->message == NULL) {
	        self->message = EVP_MD_CTX_create();
	        if (!EVP_DigestInit_ex(self->message, EVP_sha1(), NULL)) {
	            croak("cannot initialize SHA1 context");
	        }
	    }

	    for (i = 1; i < items; i++) {
	        data = ST(i);
	        in = (unsigned char *)SvPV(data, l);
	        if (!EVP_DigestUpdate(self->message, in, l)) {
	            croak("cannot update SHA1 context");
	        }
	    }
	}


int
verify(self, mac)
	Crypt::Keyczar::DsaPublicKeyEngine self
	SV *mac
	CODE:
	{
	    unsigned char md[EVP_MAX_MD_SIZE];
	    unsigned int l = 0;
	    int rc;
	    STRLEN in_l;
	    unsigned char *in;

	    if (self->message == NULL) {
	        RETVAL = 0;
	        return;
	    }
	    EVP_DigestFinal_ex(self->message, md, &l);
	    in = (unsigned char *)SvPV(mac, in_l);
	    rc = DSA_verify(0, md, l, in, in_l, self->dsa);
	    if (rc == -1) {
	        crypt__keyczar__util__croak_openssl();
	        /* NOTREACHED */
	    }
	    RETVAL = rc == 1;
	}
	OUTPUT:
	    RETVAL