Separate DSA functionality from ASN.1 encoding.

New functions DSA_do_sign and DSA_do_verify to provide access to
the raw DSA values.

crypto/dsa/Makefile.ssl

@@ -22,8 +22,8 @@ TEST=dsatest.c
 APPS=
 
 LIB=$(TOP)/libcrypto.a
-LIBSRC= dsa_gen.c dsa_key.c dsa_lib.c dsa_vrf.c dsa_sign.c $(ERRC).c
-LIBOBJ= dsa_gen.o dsa_key.o dsa_lib.o dsa_vrf.o dsa_sign.o $(ERRC).o
+LIBSRC= dsa_gen.c dsa_key.c dsa_lib.c dsa_asn1.c dsa_vrf.c dsa_sign.c $(ERRC).c
+LIBOBJ= dsa_gen.o dsa_key.o dsa_lib.o dsa_asn1.o dsa_vrf.o dsa_sign.o $(ERRC).o
 
 SRC= $(LIBSRC)
 
@@ -84,6 +84,16 @@ $(ERRC).c: $(ERR).err
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
+dsa_asn1.o: ../../include/asn1.h ../../include/asn1_mac.h ../../include/bio.h
+dsa_asn1.o: ../../include/blowfish.h ../../include/bn.h ../../include/buffer.h
+dsa_asn1.o: ../../include/cast.h ../../include/des.h ../../include/dh.h
+dsa_asn1.o: ../../include/e_os.h ../../include/err.h ../../include/evp.h
+dsa_asn1.o: ../../include/idea.h ../../include/md2.h ../../include/md5.h
+dsa_asn1.o: ../../include/mdc2.h ../../include/objects.h ../../include/pkcs7.h
+dsa_asn1.o: ../../include/rc2.h ../../include/rc4.h ../../include/rc5.h
+dsa_asn1.o: ../../include/ripemd.h ../../include/rsa.h ../../include/sha.h
+dsa_asn1.o: ../../include/stack.h ../../include/x509.h ../../include/x509_vfy.h
+dsa_asn1.o: ../cryptlib.h ../crypto.h ../opensslv.h dsa.h
 dsa_err.o: ../../include/bn.h ../../include/err.h dsa.h
 dsa_gen.o: ../../include/bio.h ../../include/bn.h ../../include/buffer.h
 dsa_gen.o: ../../include/e_os.h ../../include/err.h ../../include/rand.h

crypto/dsa/dsa.err

@@ -10,6 +10,11 @@
 #define DSA_F_DSA_SIGN					 106
 #define DSA_F_DSA_SIGN_SETUP				 107
 #define DSA_F_DSA_VERIFY				 108
+#define DSA_F_DSA_SIG_NEW				 109
+#define DSA_F_D2I_DSA_SIG				 110
+#define DSA_F_I2D_DSA_SIG				 111
+#define DSA_F_DSA_DO_SIGN				 112
+#define DSA_F_DSA_DO_VERIFY				 113
 
 /* Reason codes. */
 #define DSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE		 100

crypto/dsa/dsa.h

@@ -97,6 +97,12 @@ typedef struct dsa_st
 	int references;
 	} DSA;
 
+typedef struct DSA_SIG_st
+	{
+	BIGNUM *r;
+	BIGNUM *s;
+	} DSA_SIG;
+
 #define DSAparams_dup(x) (DSA *)ASN1_dup((int (*)())i2d_DSAparams, \
 		(char *(*)())d2i_DSAparams,(char *)(x))
 #define d2i_DSAparams_fp(fp,x) (DSA *)ASN1_d2i_fp((char *(*)())DSA_new, \
@@ -110,6 +116,15 @@ typedef struct dsa_st
 
 #ifndef NOPROTO
 
+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(unsigned char *dgst,int dlen,DSA *dsa);
+int	DSA_do_verify(unsigned char *dgst,int dgst_len,
+		DSA_SIG *sig,DSA *dsa);
+
 DSA *	DSA_new(void);
 int	DSA_size(DSA *);
 	/* next 4 return -1 on error */
@@ -146,6 +161,14 @@ int DSA_is_prime(BIGNUM *q,void (*callback)(),char *cb_arg);
 
 #else
 
+DSA_SIG * DSA_SIG_new();
+void	DSA_SIG_free();
+int	i2d_DSA_SIG();
+DSA_SIG * d2i_DSA_SIG();
+
+DSA_SIG * DSA_do_sign();
+int	DSA_do_verify();
+
 DSA *	DSA_new();
 int	DSA_size();
 int	DSA_sign_setup();
@@ -189,6 +212,11 @@ int	DSA_print_fp();
 #define DSA_F_DSA_SIGN					 106
 #define DSA_F_DSA_SIGN_SETUP				 107
 #define DSA_F_DSA_VERIFY				 108
+#define DSA_F_DSA_SIG_NEW				 109
+#define DSA_F_D2I_DSA_SIG				 110
+#define DSA_F_I2D_DSA_SIG				 111
+#define DSA_F_DSA_DO_SIGN				 112
+#define DSA_F_DSA_DO_VERIFY				 113
 
 /* Reason codes. */
 #define DSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE		 100

crypto/dsa/dsa_asn1.c

+/* crypto/dsa/dsa_asn1.c */
+
+#include <stdio.h>
+#include "cryptlib.h"
+#include "dsa.h"
+#include "asn1.h"
+#include "asn1_mac.h"
+
+DSA_SIG *DSA_SIG_new(void)
+{
+	DSA_SIG *ret;
+
+	ret = Malloc(sizeof(DSA_SIG));
+	if (ret == NULL)
+		{
+		DSAerr(DSA_F_DSA_SIG_NEW,ERR_R_MALLOC_FAILURE);
+		return(NULL);
+		}
+	ret->r = NULL;
+	ret->s = NULL;
+	return(ret);
+}
+
+void DSA_SIG_free(r)
+DSA_SIG *r;
+{
+	if (r == NULL) return;
+	if (r->r) BN_clear_free(r->r);
+	if (r->s) BN_clear_free(r->s);
+	Free(r);
+}
+
+int i2d_DSA_SIG(v,pp)
+DSA_SIG *v;
+unsigned char **pp;
+{
+	int t=0,len;
+	ASN1_INTEGER rbs,sbs;
+	unsigned char *p;
+
+	rbs.data=Malloc(BN_num_bits(v->r)/8+1);
+	if (rbs.data == NULL)
+		{
+		DSAerr(DSA_F_I2D_DSA_SIG, ERR_R_MALLOC_FAILURE);
+		return(0);
+		}
+	rbs.type=V_ASN1_INTEGER;
+	rbs.length=BN_bn2bin(v->r,rbs.data);
+	sbs.data=Malloc(BN_num_bits(v->s)/8+1);
+	if (sbs.data == NULL)
+		{
+		Free(rbs.data);
+		DSAerr(DSA_F_I2D_DSA_SIG, ERR_R_MALLOC_FAILURE);
+		return(0);
+		}
+	sbs.type=V_ASN1_INTEGER;
+	sbs.length=BN_bn2bin(v->s,sbs.data);
+
+	len=i2d_ASN1_INTEGER(&rbs,NULL);
+	len+=i2d_ASN1_INTEGER(&sbs,NULL);
+
+	if (pp)
+		{
+		p=*pp;
+		ASN1_put_object(&p,1,len,V_ASN1_SEQUENCE,V_ASN1_UNIVERSAL);
+		i2d_ASN1_INTEGER(&rbs,&p);
+		i2d_ASN1_INTEGER(&sbs,&p);
+		}
+	t=ASN1_object_size(1,len,V_ASN1_SEQUENCE);
+	Free(rbs.data);
+	Free(sbs.data);
+	return(t);
+}
+
+DSA_SIG *d2i_DSA_SIG(a,pp,length)
+DSA_SIG **a;
+unsigned char **pp;
+long length;
+{
+	int i=ERR_R_NESTED_ASN1_ERROR;
+	ASN1_INTEGER *bs=NULL;
+	M_ASN1_D2I_vars(a,DSA_SIG *,DSA_SIG_new);
+
+	M_ASN1_D2I_Init();
+	M_ASN1_D2I_start_sequence();
+	M_ASN1_D2I_get(bs,d2i_ASN1_INTEGER);
+	if ((ret->r=BN_bin2bn(bs->data,bs->length,ret->r)) == NULL)
+		goto err_bn;
+	M_ASN1_D2I_get(bs,d2i_ASN1_INTEGER);
+	if ((ret->s=BN_bin2bn(bs->data,bs->length,ret->s)) == NULL)
+		goto err_bn;
+	ASN1_BIT_STRING_free(bs);
+	M_ASN1_D2I_Finish_2(a);
+
+err_bn:
+	i=ERR_R_BN_LIB;
+err:
+	DSAerr(DSA_F_D2I_DSA_SIG,i);
+	if ((ret != NULL) && ((a == NULL) || (*a != ret))) DSA_SIG_free(ret);
+	if (bs != NULL) ASN1_BIT_STRING_free(bs);
+	return(NULL);
+}

crypto/dsa/dsa_err.c

@@ -72,6 +72,11 @@ static ERR_STRING_DATA DSA_str_functs[]=
 {ERR_PACK(0,DSA_F_DSA_SIGN,0),	"DSA_sign"},
 {ERR_PACK(0,DSA_F_DSA_SIGN_SETUP,0),	"DSA_sign_setup"},
 {ERR_PACK(0,DSA_F_DSA_VERIFY,0),	"DSA_verify"},
+{ERR_PACK(0,DSA_F_DSA_SIG_NEW,0),	"DSA_SIG_new"},
+{ERR_PACK(0,DSA_F_D2I_DSA_SIG,0),	"d2i_DSA_SIG"},
+{ERR_PACK(0,DSA_F_I2D_DSA_SIG,0),	"i2d_DSA_SIG"},
+{ERR_PACK(0,DSA_F_DSA_DO_SIGN,0),	"DSA_do_sign"},
+{ERR_PACK(0,DSA_F_DSA_DO_VERIFY,0),	"DSA_do_verify"},
 {0,NULL},
 	};
 

crypto/dsa/dsa_sign.c

@@ -65,30 +65,22 @@
 #include "rand.h"
 #include "asn1.h"
 
-/* data has already been hashed (probably with SHA or SHA-1). */
-/*	DSAerr(DSA_F_DSA_SIGN,DSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE); */
-
-int DSA_sign(type,dgst,dlen,sig,siglen,dsa)
-int type;
+DSA_SIG * DSA_do_sign(dgst,dlen,dsa)
 unsigned char *dgst;
 int dlen;
-unsigned char *sig;	/* out */
-unsigned int *siglen;	/* out */
 DSA *dsa;
 	{
-	BIGNUM *kinv=NULL,*r=NULL;
+	BIGNUM *kinv=NULL,*r=NULL,*s=NULL;
 	BIGNUM m;
-	BIGNUM xr,s;
+	BIGNUM xr;
 	BN_CTX *ctx=NULL;
-	unsigned char *p;
-	int i,len=0,ret=0,reason=ERR_R_BN_LIB;
-        ASN1_INTEGER rbs,sbs;
-	MS_STATIC unsigned char rbuf[50]; /* assuming r is 20 bytes +extra */
-	MS_STATIC unsigned char sbuf[50]; /* assuming s is 20 bytes +extra */
+	int i,reason=ERR_R_BN_LIB;
+	DSA_SIG *ret=NULL;
 
 	BN_init(&m);
 	BN_init(&xr);
-	BN_init(&s);
+	s=BN_new();
+	if (s == NULL) goto err;
 
 	i=BN_num_bytes(dsa->q); /* should be 20 */
 	if ((dlen > i) || (dlen > 50))
@@ -116,44 +108,51 @@ DSA *dsa;
 
 	/* Compute  s = inv(k) (m + xr) mod q */
 	if (!BN_mod_mul(&xr,dsa->priv_key,r,dsa->q,ctx)) goto err;/* s = xr */
-	if (!BN_add(&s, &xr, &m)) goto err;		/* s = m + xr */
-	if (BN_cmp(&s,dsa->q) > 0)
-		BN_sub(&s,&s,dsa->q);
-	if (!BN_mod_mul(&s,&s,kinv,dsa->q,ctx)) goto err;
-
-	/*
-	 * Now create a ASN.1 sequence of the integers R and S.
-	 */
-	rbs.data=rbuf;
-	sbs.data=sbuf;
-	rbs.type = V_ASN1_INTEGER;
-	sbs.type = V_ASN1_INTEGER;
-	rbs.length=BN_bn2bin(r,rbs.data);
-	sbs.length=BN_bn2bin(&s,sbs.data);
-
-	len =i2d_ASN1_INTEGER(&rbs,NULL);
-	len+=i2d_ASN1_INTEGER(&sbs,NULL);
-
-	p=sig;
-	ASN1_put_object(&p,1,len,V_ASN1_SEQUENCE,V_ASN1_UNIVERSAL);
-	i2d_ASN1_INTEGER(&rbs,&p);
-	i2d_ASN1_INTEGER(&sbs,&p);
-	*siglen=(p-sig);
-	ret=1;
+	if (!BN_add(s, &xr, &m)) goto err;		/* s = m + xr */
+	if (BN_cmp(s,dsa->q) > 0)
+		BN_sub(s,s,dsa->q);
+	if (!BN_mod_mul(s,s,kinv,dsa->q,ctx)) goto err;
+
+	ret=DSA_SIG_new();
+	if (ret == NULL) goto err;
+	ret->r = r;
+	ret->s = s;
+	
 err:
-	if (!ret) DSAerr(DSA_F_DSA_SIGN,reason);
-		
-#if 1 /* do the right thing :-) */
-	if (kinv != NULL) BN_clear_free(kinv);
-	if (r != NULL) BN_clear_free(r);
-#endif
+	if (!ret)
+		{
+		DSAerr(DSA_F_DSA_DO_SIGN,reason);
+		BN_free(r);
+		BN_free(s);
+		}
 	if (ctx != NULL) BN_CTX_free(ctx);
 	BN_clear_free(&m);
 	BN_clear_free(&xr);
-	BN_clear_free(&s);
 	return(ret);
 	}
 
+/* data has already been hashed (probably with SHA or SHA-1). */
+
+int DSA_sign(type,dgst,dlen,sig,siglen,dsa)
+int type;
+unsigned char *dgst;
+int dlen;
+unsigned char *sig;    /* out */
+unsigned int *siglen;  /* out */
+DSA *dsa;
+	{
+	DSA_SIG *s;
+	s=DSA_do_sign(dgst,dlen,dsa);
+	if (s == NULL)
+		{
+		*siglen=0;
+		return(0);
+		}
+	*siglen=i2d_DSA_SIG(s,&sig);
+	DSA_SIG_free(s);
+	return(1);
+	}
+
 int DSA_sign_setup(dsa,ctx_in,kinvp,rp)
 DSA *dsa;
 BN_CTX *ctx_in;

crypto/dsa/dsa_vrf.c

@@ -56,7 +56,7 @@
  * [including the GNU Public Licence.]
  */
 
-/* Origional version from Steven Schoch <schoch@sheba.arc.nasa.gov> */
+/* Original version from Steven Schoch <schoch@sheba.arc.nasa.gov> */
 
 #include <stdio.h>
 #include "cryptlib.h"
@@ -66,57 +66,34 @@
 #include "asn1.h"
 #include "asn1_mac.h"
 
-/* data has already been hashed (probably with SHA or SHA-1). */
-/* returns
- *	 1: correct signature
- *	 0: incorrect signature
- *	-1: error
- */
-int DSA_verify(type,dgst,dgst_len,sigbuf,siglen, dsa)
-int type;
+int DSA_do_verify(dgst,dgst_len,sig,dsa)
 unsigned char *dgst;
 int dgst_len;
-unsigned char *sigbuf;
-int siglen;
+DSA_SIG *sig;
 DSA *dsa;
 	{
-	/* The next 3 are used by the M_ASN1 macros */
-	long length=siglen;
-	ASN1_CTX c;
-	unsigned char **pp= &sigbuf;
 	BN_CTX *ctx;
-	BIGNUM r,u1,u2,t1;
-	ASN1_INTEGER *bs=NULL;
+	BIGNUM u1,u2,t1;
 	BN_MONT_CTX *mont=NULL;
 	int ret = -1;
 
 	if ((ctx=BN_CTX_new()) == NULL) goto err;
-
 	BN_init(&u1);
 	BN_init(&u2);
-	BN_init(&r);
 	BN_init(&t1);
 
-	M_ASN1_D2I_Init();
-	M_ASN1_D2I_start_sequence();
-        M_ASN1_D2I_get(bs,d2i_ASN1_INTEGER);
-        if ((BN_bin2bn(bs->data,bs->length,&r)) == NULL) goto err_bn;
-        M_ASN1_D2I_get(bs,d2i_ASN1_INTEGER);
-        if ((BN_bin2bn(bs->data,bs->length,&u1)) == NULL) goto err_bn;
-	if (!asn1_Finish(&c)) goto err;
-
 	/* Calculate W = inv(S) mod Q
 	 * save W in u2 */
-	if ((BN_mod_inverse(&u2,&u1,dsa->q,ctx)) == NULL) goto err_bn;
+	if ((BN_mod_inverse(&u2,sig->s,dsa->q,ctx)) == NULL) goto err;
 
 	/* save M in u1 */
-	if (BN_bin2bn(dgst,dgst_len,&u1) == NULL) goto err_bn;
+	if (BN_bin2bn(dgst,dgst_len,&u1) == NULL) goto err;
 
 	/* u1 = M * w mod q */
-	if (!BN_mod_mul(&u1,&u1,&u2,dsa->q,ctx)) goto err_bn;
+	if (!BN_mod_mul(&u1,&u1,&u2,dsa->q,ctx)) goto err;
 
 	/* u2 = r * w mod q */
-	if (!BN_mod_mul(&u2,&r,&u2,dsa->q,ctx)) goto err_bn;
+	if (!BN_mod_mul(&u2,sig->r,&u2,dsa->q,ctx)) goto err;
 
 	if ((dsa->method_mont_p == NULL) && (dsa->flags & DSA_FLAG_CACHE_MONT_P))
 		{
@@ -133,42 +110,59 @@ DSA *dsa;
 	BN_init(&t2);
 	/* v = ( g^u1 * y^u2 mod p ) mod q */
 	/* let t1 = g ^ u1 mod p */
-	if (!BN_mod_exp_mont(&t1,dsa->g,&u1,dsa->p,ctx,mont)) goto err_bn;
+	if (!BN_mod_exp_mont(&t1,dsa->g,&u1,dsa->p,ctx,mont)) goto err;
 	/* let t2 = y ^ u2 mod p */
-	if (!BN_mod_exp_mont(&t2,dsa->pub_key,&u2,dsa->p,ctx,mont)) goto err_bn;
+	if (!BN_mod_exp_mont(&t2,dsa->pub_key,&u2,dsa->p,ctx,mont)) goto err;
 	/* let u1 = t1 * t2 mod p */
 	if (!BN_mod_mul(&u1,&t1,&t2,dsa->p,ctx)) goto err_bn;
 	BN_free(&t2);
 	}
 	/* let u1 = u1 mod q */
-	if (!BN_mod(&u1,&u1,dsa->q,ctx)) goto err_bn;
+	if (!BN_mod(&u1,&u1,dsa->q,ctx)) goto err;
 #else
 	{
 	if (!BN_mod_exp2_mont(&t1,dsa->g,&u1,dsa->pub_key,&u2,dsa->p,ctx,mont))
-		goto err_bn;
+		goto err;
 	/* BN_copy(&u1,&t1); */
 	/* let u1 = u1 mod q */
-	if (!BN_mod(&u1,&t1,dsa->q,ctx)) goto err_bn;
+	if (!BN_mod(&u1,&t1,dsa->q,ctx)) goto err;
 	}
 #endif
 	/* V is now in u1.  If the signature is correct, it will be
 	 * equal to R. */
-	ret=(BN_ucmp(&u1, &r) == 0);
-	if (0)
-		{
-err: /* ASN1 error */
-		DSAerr(DSA_F_DSA_VERIFY,c.error);
-		}
-	if (0)
-		{
-err_bn: /* BN error */
-		DSAerr(DSA_F_DSA_VERIFY,ERR_R_BN_LIB);
-		}
+	ret=(BN_ucmp(&u1, sig->r) == 0);
+
+	err:
+	if (ret != 1) DSAerr(DSA_F_DSA_DO_VERIFY,ERR_R_BN_LIB);
 	if (ctx != NULL) BN_CTX_free(ctx);
-	BN_free(&r);
 	BN_free(&u1);
 	BN_free(&u2);
 	BN_free(&t1);
-	if (bs != NULL) ASN1_BIT_STRING_free(bs);
+	return(ret);
+	}
+
+/* data has already been hashed (probably with SHA or SHA-1). */
+/* returns
+ *      1: correct signature
+ *      0: incorrect signature
+ *     -1: error
+ */
+int DSA_verify(type,dgst,dgst_len,sigbuf,siglen,dsa)
+int type;
+unsigned char *dgst;
+int dgst_len;
+unsigned char *sigbuf;
+int siglen;
+DSA *dsa;
+	{
+	DSA_SIG *s;
+	int ret=-1;
+
+	s = DSA_SIG_new();
+	if (s == NULL) return(ret);
+	if (d2i_DSA_SIG(&s,&sigbuf,siglen) == NULL) goto err;
+	ret=DSA_do_verify(dgst,dgst_len,s,dsa);
+err:
+	DSA_SIG_free(s);
 	return(ret);
 	}

crypto/dsa/dsatest.c

@@ -125,6 +125,8 @@ char **argv;
 	int counter,ret=0,i,j;
 	unsigned char buf[256];
 	unsigned long h;
+	unsigned char sig[256];
+	int siglen;
 
 	if (bio_err == NULL)
 		bio_err=BIO_new_fp(stderr,BIO_NOCLOSE);
@@ -178,8 +180,10 @@ char **argv;
 		BIO_printf(bio_err,"g value is wrong\n");
 		goto end;
 		}
-
-	ret=1;
+	DSA_generate_key(dsa);
+	DSA_sign(0, "12345678901234567890", 20, sig, &siglen, dsa);
+	if (DSA_verify(0, "12345678901234567890", 20, sig, siglen, dsa) == 1)
+		ret=1;
 end:
 	if (!ret)
 		ERR_print_errors(bio_err);

util/libeay.num

@@ -1304,3 +1304,10 @@ i2d_SXNETID                             1329
 d2i_SXNETID                             1330
 SXNETID_new                             1331
 SXNETID_free                            1332
+DSA_SIG_new								1333
+DSA_SIG_free							1334
+DSA_do_sign								1335
+DSA_do_verify							1336
+d2i_DSA_SIG								1337
+i2d_DSA_SIG								1338
+