From 8e8972bb680c7f91b9f615dc0fee3b1eb2cbed57 Mon Sep 17 00:00:00 2001
From: "Dr. Stephen Henson" <steve@openssl.org>
Date: Fri, 19 Jan 2001 14:21:48 +0000
Subject: [PATCH] Fixes to various ASN1_INTEGER routines for negative case.

Enhance s2i_ASN1_INTEGER().
---
 CHANGES                |  8 ++++++++
 apps/ocsp.c            |  2 +-
 crypto/asn1/a_int.c    |  6 ++++++
 crypto/asn1/f_int.c    |  8 +++++++-
 crypto/x509v3/v3_utl.c | 27 +++++++++++++++++++++++----
 5 files changed, 45 insertions(+), 6 deletions(-)

diff --git a/CHANGES b/CHANGES
index eeddf41840..f548204e31 100644
--- a/CHANGES
+++ b/CHANGES
@@ -3,6 +3,14 @@
 
  Changes between 0.9.6 and 0.9.7  [xx XXX 2000]
 
+  *) Fixes to BN_to_ASN1_INTEGER when bn is zero. This would previously
+     result in a zero length in the ASN1_INTEGER structure which was
+     not consistent with the structure when d2i_ASN1_INTEGER() was used
+     and would cause ASN1_INTEGER_cmp() to fail. Enhance s2i_ASN1_INTEGER()
+     to cope with hex and negative integers. Fix bug in i2a_ASN1_INTEGER()
+     where it did not print out a minus for negative ASN1_INTEGER.
+     [Steve Henson]
+
   *) Fix 'openssl passwd -1'.
      [Bodo Moeller]
 
diff --git a/apps/ocsp.c b/apps/ocsp.c
index f23aa4c52a..eaba15f309 100644
--- a/apps/ocsp.c
+++ b/apps/ocsp.c
@@ -585,7 +585,7 @@ static int print_ocsp_summary(BIO *out, OCSP_BASICRESP *bs, OCSP_REQUEST *req,
 		if (status != V_OCSP_CERTSTATUS_REVOKED)
 			continue;
 
-		if (reason > 0)
+		if (reason != -1)
 			BIO_printf(out, "\tReason: %s\n",
 				OCSP_crl_reason_str(reason));
 
diff --git a/crypto/asn1/a_int.c b/crypto/asn1/a_int.c
index b0fc97ea27..496704b9a5 100644
--- a/crypto/asn1/a_int.c
+++ b/crypto/asn1/a_int.c
@@ -399,6 +399,12 @@ ASN1_INTEGER *BN_to_ASN1_INTEGER(BIGNUM *bn, ASN1_INTEGER *ai)
 	len=((j == 0)?0:((j/8)+1));
 	ret->data=(unsigned char *)OPENSSL_malloc(len+4);
 	ret->length=BN_bn2bin(bn,ret->data);
+	/* Correct zero case */
+	if(!ret->length)
+		{
+		ret->data[0] = 0;
+		ret->length = 1;
+		}
 	return(ret);
 err:
 	if (ret != ai) M_ASN1_INTEGER_free(ret);
diff --git a/crypto/asn1/f_int.c b/crypto/asn1/f_int.c
index 6b090f6740..48cc3bfb90 100644
--- a/crypto/asn1/f_int.c
+++ b/crypto/asn1/f_int.c
@@ -69,10 +69,16 @@ int i2a_ASN1_INTEGER(BIO *bp, ASN1_INTEGER *a)
 
 	if (a == NULL) return(0);
 
+	if (a->type & V_ASN1_NEG)
+		{
+		if (BIO_write(bp, "-", 1) != 1) goto err;
+		n = 1;
+		}
+
 	if (a->length == 0)
 		{
 		if (BIO_write(bp,"00",2) != 2) goto err;
-		n=2;
+		n += 2;
 		}
 	else
 		{
diff --git a/crypto/x509v3/v3_utl.c b/crypto/x509v3/v3_utl.c
index 727a93ff51..434ddbbc3c 100644
--- a/crypto/x509v3/v3_utl.c
+++ b/crypto/x509v3/v3_utl.c
@@ -154,21 +154,40 @@ ASN1_INTEGER *s2i_ASN1_INTEGER(X509V3_EXT_METHOD *method, char *value)
 {
 	BIGNUM *bn = NULL;
 	ASN1_INTEGER *aint;
+	int isneg, ishex;
+	int ret;
 	bn = BN_new();
-	if(!value) {
+	if (!value) {
 		X509V3err(X509V3_F_S2I_ASN1_INTEGER,X509V3_R_INVALID_NULL_VALUE);
 		return 0;
 	}
-	if(!BN_dec2bn(&bn, value)) {
+	if (value[0] == '-') {
+		value++;
+		isneg = 1;
+	} else isneg = 0;
+
+	if (value[0] == '0' && ((value[1] == 'x') || (value[1] == 'X'))) {
+		value += 2;
+		ishex = 1;
+	} else ishex = 0;
+
+	if (ishex) ret = BN_hex2bn(&bn, value);
+	else ret = BN_dec2bn(&bn, value);
+
+	if (!ret) {
 		X509V3err(X509V3_F_S2I_ASN1_INTEGER,X509V3_R_BN_DEC2BN_ERROR);
 		return 0;
 	}
 
-	if(!(aint = BN_to_ASN1_INTEGER(bn, NULL))) {
+	if (isneg && BN_is_zero(bn)) isneg = 0;
+
+	aint = BN_to_ASN1_INTEGER(bn, NULL);
+	BN_free(bn);
+	if (!aint) {
 		X509V3err(X509V3_F_S2I_ASN1_INTEGER,X509V3_R_BN_TO_ASN1_INTEGER_ERROR);
 		return 0;
 	}
-	BN_free(bn);
+	if (isneg) aint->type |= V_ASN1_NEG;
 	return aint;
 }
 
-- 
2.25.1