From 074a30618fd6776453bfce5e06b05724aa99d5d4 Mon Sep 17 00:00:00 2001
From: Love Hornquist Astrand <lha@h5l.org>
Date: Mon, 25 Apr 2011 11:33:58 -0700
Subject: [PATCH] Try to parse inner structure of an octet string (limited to
 CONS SEQ right now)

---
 lib/asn1/asn1_print.c | 38 ++++++++++++++++++++++++++++++--------
 1 file changed, 30 insertions(+), 8 deletions(-)

diff --git a/lib/asn1/asn1_print.c b/lib/asn1/asn1_print.c
index 279e969b0..917b8cd5f 100644
--- a/lib/asn1/asn1_print.c
+++ b/lib/asn1/asn1_print.c
@@ -41,9 +41,8 @@
 #include <err.h>
 #include <der.h>
 
-RCSID("$Id$");
-
 static int indent_flag = 1;
+static int inner_flag = 0;
 
 static unsigned long indefinite_form_loop;
 static unsigned long indefinite_form_loop_max = 10000;
@@ -167,17 +166,39 @@ loop (unsigned char *buf, size_t len, int indent)
 	    }
 	    case UT_OctetString : {
 		heim_octet_string str;
-		int i;
-		unsigned char *uc;
+		size_t i;
 
 		ret = der_get_octet_string (buf, length, &str, NULL);
 		if (ret)
 		    errx (1, "der_get_octet_string: %s", error_message (ret));
 		printf ("(length %lu), ", (unsigned long)length);
-		uc = (unsigned char *)str.data;
-		for (i = 0; i < min(16,length); ++i)
-		    printf ("%02x", uc[i]);
-		printf ("\n");
+
+		if (inner_flag) {
+		    Der_class class;
+		    Der_type type;
+		    unsigned int tag;
+
+		    ret = der_get_tag(str.data, str.length,
+				      &class, &type, &tag, &sz);
+		    if (ret || sz > str.length ||
+			type != CONS || tag != UT_Sequence)
+			goto just_an_octet_string;
+		    
+		    printf("{\n");
+		    loop (str.data, str.length, indent + 2);
+		    for (i = 0; i < indent; ++i)
+			printf (" ");
+		    printf ("}\n");
+
+		} else {
+		    unsigned char *uc;
+
+		just_an_octet_string:
+		    uc = (unsigned char *)str.data;
+		    for (i = 0; i < min(16,length); ++i)
+			printf ("%02x", uc[i]);
+		    printf ("\n");
+		}
 		free (str.data);
 		break;
 	    }
@@ -295,6 +316,7 @@ static int version_flag;
 static int help_flag;
 struct getargs args[] = {
     { "indent", 0, arg_negative_flag, &indent_flag },
+    { "inner", 0, arg_flag, &inner_flag, "try to parse inner structures of OCTET STRING" },
     { "version", 0, arg_flag, &version_flag },
     { "help", 0, arg_flag, &help_flag }
 };
-- 
2.11.4.GIT