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 aedc268b69e13222247bbdee819847c9e0e0d9e4..a714dd5cd72ff7679a2f60777e7ab35eb8576daf 100644 (file)
--- 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 7fc14d3296c1ccb1db5b433b5c316375c265bfcc..264ebf2393a2e7a3ab986fd25d8810f5bc7b1bc1 100644 (file)
--- 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