From: Dr. Stephen Henson <steve@openssl.org>
Date: Mon, 3 Jan 2011 01:27:00 +0000 (+0000)
Subject: Fix escaping code for string printing. If *any* escaping is enabled we
X-Git-Tag: OpenSSL_1_0_0d~16
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=2fcf251d3da65dd7cc8230257b6ba55d97b0564a;p=oweals%2Fopenssl.git

Fix escaping code for string printing. If *any* escaping is enabled we
must escape the escape character itself (backslash).
---

diff --git a/CHANGES b/CHANGES
index aedc268b69..a714dd5cd7 100644
--- a/CHANGES
+++ b/CHANGES
@@ -4,7 +4,10 @@
 
  Changes between 1.0.0c and 1.0.0d [xx XXX xxxx]
 
-  *)
+  *) Fix bug in string printing code: if *any* escaping is enabled we must
+     escape the escape character (backslash) or the resulting string is
+     ambiguous.
+     [Steve Henson]
 
  Changes between 1.0.0b and 1.0.0c  [2 Dec 2010]
 
diff --git a/crypto/asn1/a_strex.c b/crypto/asn1/a_strex.c
index 7fc14d3296..264ebf2393 100644
--- a/crypto/asn1/a_strex.c
+++ b/crypto/asn1/a_strex.c
@@ -74,6 +74,11 @@
 
 #define CHARTYPE_BS_ESC		(ASN1_STRFLGS_ESC_2253 | CHARTYPE_FIRST_ESC_2253 | CHARTYPE_LAST_ESC_2253)
 
+#define ESC_FLAGS (ASN1_STRFLGS_ESC_2253 | \
+		  ASN1_STRFLGS_ESC_QUOTE | \
+		  ASN1_STRFLGS_ESC_CTRL | \
+		  ASN1_STRFLGS_ESC_MSB)
+
 
 /* Three IO functions for sending data to memory, a BIO and
  * and a FILE pointer.
@@ -148,6 +153,13 @@ static int do_esc_char(unsigned long c, unsigned char flags, char *do_quotes, ch
 		if(!io_ch(arg, tmphex, 3)) return -1;
 		return 3;
 	}
+	/* If we get this far and do any escaping at all must escape 
+	 * the escape character itself: backslash.
+	 */
+	if (chtmp == '\\' && flags & ESC_FLAGS) {
+		if(!io_ch(arg, "\\\\", 2)) return -1;
+		return 2;
+	}
 	if(!io_ch(arg, &chtmp, 1)) return -1;
 	return 1;
 }
@@ -292,11 +304,6 @@ static const signed char tag2nbyte[] = {
 	4, -1, 2		/* 28-30 */
 };
 
-#define ESC_FLAGS (ASN1_STRFLGS_ESC_2253 | \
-		  ASN1_STRFLGS_ESC_QUOTE | \
-		  ASN1_STRFLGS_ESC_CTRL | \
-		  ASN1_STRFLGS_ESC_MSB)
-
 /* This is the main function, print out an
  * ASN1_STRING taking note of various escape
  * and display options. Returns number of