From: Dr. Stephen Henson <steve@openssl.org>
Date: Wed, 12 Apr 2006 17:14:48 +0000 (+0000)
Subject: Extend DH ASN1 method to support public key encode/decode and parameter
X-Git-Tag: OpenSSL_0_9_8k^2~1400
X-Git-Url: https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff_plain;h=ceb46789563c251cc8e682e1a95cb180fdd50cb0

Extend DH ASN1 method to support public key encode/decode and parameter
utilities.
---

diff --git a/crypto/dh/dh.h b/crypto/dh/dh.h
index 48b6283704..ef918b63cf 100644
--- a/crypto/dh/dh.h
+++ b/crypto/dh/dh.h
@@ -216,13 +216,18 @@ void ERR_load_DH_strings(void);
 #define DH_F_DH_BUILTIN_GENPARAMS			 106
 #define DH_F_DH_NEW_METHOD				 105
 #define DH_F_DH_PARAM_DECODE				 107
+#define DH_F_DH_PUB_DECODE				 108
+#define DH_F_DH_PUB_ENCODE				 109
 #define DH_F_GENERATE_KEY				 103
 #define DH_F_GENERATE_PARAMETERS			 104
 
 /* Reason codes. */
 #define DH_R_BAD_GENERATOR				 101
+#define DH_R_BN_DECODE_ERROR				 103
+#define DH_R_DECODE_ERROR				 104
 #define DH_R_INVALID_PUBKEY				 102
 #define DH_R_NO_PRIVATE_VALUE				 100
+#define DH_R_PARAMETER_ENCODING_ERROR			 105
 
 #ifdef  __cplusplus
 }
diff --git a/crypto/dh/dh_ameth.c b/crypto/dh/dh_ameth.c
index 03b40d0e5c..ba22f34d40 100644
--- a/crypto/dh/dh_ameth.c
+++ b/crypto/dh/dh_ameth.c
@@ -67,6 +67,122 @@ static void int_dh_free(EVP_PKEY *pkey)
 	DH_free(pkey->pkey.dh);
 	}
 
+static int dh_pub_decode(EVP_PKEY *pkey, X509_PUBKEY *pubkey)
+	{
+	const unsigned char *p, *pm;
+	int pklen, pmlen;
+	int ptype;
+	void *pval;
+	ASN1_STRING *pstr;
+	X509_ALGOR *palg;
+	ASN1_INTEGER *public_key = NULL;
+
+	DH *dh = NULL;
+
+	if (!X509_PUBKEY_get0_param(NULL, &p, &pklen, &palg, pubkey))
+		return 0;
+	X509_ALGOR_get0(NULL, &ptype, &pval, palg);
+
+	if (ptype != V_ASN1_SEQUENCE)
+		{
+		DHerr(DH_F_DH_PUB_DECODE, DH_R_PARAMETER_ENCODING_ERROR);
+		goto err;
+		}
+
+	pstr = pval;	
+	pm = pstr->data;
+	pmlen = pstr->length;
+
+	if (!(dh = d2i_DHparams(NULL, &pm, pmlen)))
+		{
+		DHerr(DH_F_DH_PUB_DECODE, DH_R_DECODE_ERROR);
+		goto err;
+		}
+
+	if (!(public_key=d2i_ASN1_INTEGER(NULL, &p, pklen)))
+		{
+		DHerr(DH_F_DH_PUB_DECODE, DH_R_DECODE_ERROR);
+		goto err;
+		}
+
+	/* We have parameters now set public key */
+	if (!(dh->pub_key = ASN1_INTEGER_to_BN(public_key, NULL)))
+		{
+		DHerr(DH_F_DH_PUB_DECODE, DH_R_BN_DECODE_ERROR);
+		goto err;
+		}
+
+	ASN1_INTEGER_free(public_key);
+	EVP_PKEY_assign_DH(pkey, dh);
+	return 1;
+
+	err:
+	if (pubkey)
+		ASN1_INTEGER_free(public_key);
+	if (dh)
+		DH_free(dh);
+	return 0;
+
+	}
+
+static int dh_pub_encode(X509_PUBKEY *pk, const EVP_PKEY *pkey)
+	{
+	DH *dh;
+	void *pval = NULL;
+	int ptype;
+	unsigned char *penc = NULL;
+	int penclen;
+	ASN1_STRING *str;
+	ASN1_INTEGER *pub_key = NULL;
+
+	dh=pkey->pkey.dh;
+
+	str = ASN1_STRING_new();
+	str->length = i2d_DHparams(dh, &str->data);
+	if (str->length <= 0)
+		{
+		DHerr(DH_F_DH_PUB_ENCODE, ERR_R_MALLOC_FAILURE);
+		goto err;
+		}
+	pval = str;
+	ptype = V_ASN1_SEQUENCE;
+
+	pub_key = BN_to_ASN1_INTEGER(dh->pub_key, NULL);
+	if (!pub_key)
+		goto err;
+
+	penclen = i2d_ASN1_INTEGER(pub_key, &penc);
+
+	ASN1_INTEGER_free(pub_key);
+
+	if (penclen <= 0)
+		{
+		DHerr(DH_F_DH_PUB_ENCODE, ERR_R_MALLOC_FAILURE);
+		goto err;
+		}
+
+	if (X509_PUBKEY_set0_param(pk, OBJ_nid2obj(EVP_PKEY_DH),
+				ptype, pval, penc, penclen))
+		return 1;
+
+	err:
+	if (penc)
+		OPENSSL_free(penc);
+	if (pval)
+		ASN1_STRING_free(pval);
+
+	return 0;
+	}
+
+static void update_buflen(const BIGNUM *b, size_t *pbuflen)
+	{
+	int i;
+	if (!b)
+		return;
+	if (*pbuflen < (i = (size_t)BN_num_bytes(b)))
+			*pbuflen = i;
+	}
+
 static int dh_param_decode(EVP_PKEY *pkey,
 					const unsigned char **pder, int derlen)
 	{
@@ -85,24 +201,47 @@ static int dh_param_encode(const EVP_PKEY *pkey, unsigned char **pder)
 	return i2d_DHparams(pkey->pkey.dh, pder);
 	}
 
-static int do_dhparam_print(BIO *bp, const DH *x, int indent,
-							ASN1_PCTX *ctx)
+static int do_dh_print(BIO *bp, const DH *x, int indent,
+						ASN1_PCTX *ctx, int ptype)
 	{
 	unsigned char *m=NULL;
 	int reason=ERR_R_BUF_LIB,ret=0;
-	size_t buf_len=0, i;
+	size_t buf_len=0;
+
+	const char *ktype = NULL;
+
+	BIGNUM *priv_key, *pub_key;
 
-	if (x->p)
-		buf_len = (size_t)BN_num_bytes(x->p);
+	if (ptype == 2)
+		priv_key = x->priv_key;
 	else
+		priv_key = NULL;
+
+	if (ptype > 0)
+		pub_key = x->pub_key;
+	else
+		pub_key = NULL;
+
+	update_buflen(x->p, &buf_len);
+
+	if (buf_len == 0)
 		{
 		reason = ERR_R_PASSED_NULL_PARAMETER;
 		goto err;
 		}
-	if (x->g)
-		if (buf_len < (i = (size_t)BN_num_bytes(x->g)))
-			buf_len = i;
-	m=(unsigned char *)OPENSSL_malloc(buf_len+10);
+
+	update_buflen(x->g, &buf_len);
+	update_buflen(pub_key, &buf_len);
+	update_buflen(priv_key, &buf_len);
+
+	if (ptype == 2)
+		ktype = "PKCS#3 DH Private-Key";
+	else if (ptype == 1)
+		ktype = "PKCS#3 DH Public-Key";
+	else
+		ktype = "PKCS#3 DH Parameters";
+
+	m= OPENSSL_malloc(buf_len+10);
 	if (m == NULL)
 		{
 		reason=ERR_R_MALLOC_FAILURE;
@@ -110,10 +249,13 @@ static int do_dhparam_print(BIO *bp, const DH *x, int indent,
 		}
 
 	BIO_indent(bp, indent, 128);
-	if (BIO_printf(bp,"Diffie-Hellman-Parameters: (%d bit)\n",
-		BN_num_bits(x->p)) <= 0)
+	if (BIO_printf(bp,"%s: (%d bit)\n", ktype, BN_num_bits(x->p)) <= 0)
 		goto err;
 	indent += 4;
+
+	if (!ASN1_bn_print(bp,"private-key:",priv_key,m,indent)) goto err;
+	if (!ASN1_bn_print(bp,"public-key:",pub_key,m,indent)) goto err;
+
 	if (!ASN1_bn_print(bp,"prime:",x->p,m,indent)) goto err;
 	if (!ASN1_bn_print(bp,"generator:",x->g,m,indent)) goto err;
 	if (x->length != 0)
@@ -122,6 +264,8 @@ static int do_dhparam_print(BIO *bp, const DH *x, int indent,
 		if (BIO_printf(bp,"recommended-private-length: %d bits\n",
 			(int)x->length) <= 0) goto err;
 		}
+
+
 	ret=1;
 	if (0)
 		{
@@ -132,15 +276,75 @@ err:
 	return(ret);
 	}
 
+static int int_dh_size(const EVP_PKEY *pkey)
+	{
+	return(DH_size(pkey->pkey.dh));
+	}
+
+static int dh_bits(const EVP_PKEY *pkey)
+	{
+	return BN_num_bits(pkey->pkey.dh->p);
+	}
+
+static int dh_copy_parameters(EVP_PKEY *to, const EVP_PKEY *from)
+	{
+	BIGNUM *a;
+
+	if ((a=BN_dup(from->pkey.dh->p)) == NULL)
+		return 0;
+	if (to->pkey.dsa->p != NULL)
+		BN_free(to->pkey.dh->p);
+	to->pkey.dsa->p=a;
+
+	if ((a=BN_dup(from->pkey.dh->g)) == NULL)
+		return 0;
+	if (to->pkey.dsa->g != NULL)
+		BN_free(to->pkey.dh->g);
+	to->pkey.dh->g=a;
+
+	return 1;
+	}
+
+static int dh_cmp_parameters(const EVP_PKEY *a, const EVP_PKEY *b)
+	{
+	if (	BN_cmp(a->pkey.dh->p,b->pkey.dsa->p) ||
+		BN_cmp(a->pkey.dh->g,b->pkey.dsa->g))
+		return 0;
+	else
+		return 1;
+	}
+
+static int dh_pub_cmp(const EVP_PKEY *a, const EVP_PKEY *b)
+	{
+	if (dh_cmp_parameters(a, b) == 0)
+		return 0;
+	if (BN_cmp(b->pkey.dh->pub_key,a->pkey.dh->pub_key) != 0)
+		return 0;
+	else
+		return 1;
+	}
+
 static int dh_param_print(BIO *bp, const EVP_PKEY *pkey, int indent,
 							ASN1_PCTX *ctx)
 	{
-	return do_dhparam_print(bp, pkey->pkey.dh, indent, ctx);
+	return do_dh_print(bp, pkey->pkey.dh, indent, ctx, 0);
+	}
+
+static int dh_public_print(BIO *bp, const EVP_PKEY *pkey, int indent,
+							ASN1_PCTX *ctx)
+	{
+	return do_dh_print(bp, pkey->pkey.dh, indent, ctx, 1);
+	}
+
+static int dh_private_print(BIO *bp, const EVP_PKEY *pkey, int indent,
+							ASN1_PCTX *ctx)
+	{
+	return do_dh_print(bp, pkey->pkey.dh, indent, ctx, 2);
 	}
 
 int DHparams_print(BIO *bp, const DH *x)
 	{
-	return do_dhparam_print(bp, x, 4, NULL);
+	return do_dh_print(bp, x, 4, NULL, 0);
 	}
 
 const EVP_PKEY_ASN1_METHOD dh_asn1_meth = 
@@ -152,21 +356,23 @@ const EVP_PKEY_ASN1_METHOD dh_asn1_meth =
 	"DH",
 	"OpenSSL PKCS#3 DH method",
 
-	0,
-	0,
-	0,
-	0,
+	dh_pub_decode,
+	dh_pub_encode,
+	dh_pub_cmp,
+	dh_public_print,
 
 	0,
 	0,
-	0,
+	dh_private_print,
 
-	0,
-	0,
+	int_dh_size,
+	dh_bits,
 
 	dh_param_decode,
 	dh_param_encode,
-	0,0,0,
+	0,
+	dh_copy_parameters,
+	dh_cmp_parameters,
 	dh_param_print,
 
 	int_dh_free,
diff --git a/crypto/dh/dh_err.c b/crypto/dh/dh_err.c
index 4e4deb6d13..2a44f1cc11 100644
--- a/crypto/dh/dh_err.c
+++ b/crypto/dh/dh_err.c
@@ -76,6 +76,8 @@ static ERR_STRING_DATA DH_str_functs[]=
 {ERR_FUNC(DH_F_DH_BUILTIN_GENPARAMS),	"DH_BUILTIN_GENPARAMS"},
 {ERR_FUNC(DH_F_DH_NEW_METHOD),	"DH_new_method"},
 {ERR_FUNC(DH_F_DH_PARAM_DECODE),	"DH_PARAM_DECODE"},
+{ERR_FUNC(DH_F_DH_PUB_DECODE),	"DH_PUB_DECODE"},
+{ERR_FUNC(DH_F_DH_PUB_ENCODE),	"DH_PUB_ENCODE"},
 {ERR_FUNC(DH_F_GENERATE_KEY),	"GENERATE_KEY"},
 {ERR_FUNC(DH_F_GENERATE_PARAMETERS),	"GENERATE_PARAMETERS"},
 {0,NULL}
@@ -84,8 +86,11 @@ static ERR_STRING_DATA DH_str_functs[]=
 static ERR_STRING_DATA DH_str_reasons[]=
 	{
 {ERR_REASON(DH_R_BAD_GENERATOR)          ,"bad generator"},
+{ERR_REASON(DH_R_BN_DECODE_ERROR)        ,"bn decode error"},
+{ERR_REASON(DH_R_DECODE_ERROR)           ,"decode error"},
 {ERR_REASON(DH_R_INVALID_PUBKEY)         ,"invalid public key"},
 {ERR_REASON(DH_R_NO_PRIVATE_VALUE)       ,"no private value"},
+{ERR_REASON(DH_R_PARAMETER_ENCODING_ERROR),"parameter encoding error"},
 {0,NULL}
 	};