From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Thu, 24 Jul 2014 00:46:09 +0000 (+0100)
Subject: Introduce adns__labels_equal and ctype_toupper
X-Git-Tag: make-bug.2014-07-26~4
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=adns.git;a=commitdiff_plain;h=e734125afd36224ccbf7e7208f7c3d9aea4fa9be

Introduce adns__labels_equal and ctype_toupper

This not only makes adns__findrr_anychk less confusing, but it also
makes it possible to reuse this functionality.

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
---

diff --git a/src/internal.h b/src/internal.h
index c2656c8..55da2b9 100644
--- a/src/internal.h
+++ b/src/internal.h
@@ -851,6 +851,8 @@ void adns__update_expires(adns_query qu, unsigned long ttl,
 
 int vbuf__append_quoted1035(vbuf *vb, const byte *buf, int len);
 
+bool adns__labels_equal(const byte *a, int al, const byte *b, int bl);
+
 /* From event.c: */
 
 void adns__tcp_broken(adns_state ads, const char *what, const char *why);
@@ -898,6 +900,9 @@ static inline int ctype_digit(int c) { return c>='0' && c<='9'; }
 static inline int ctype_alpha(int c) {
   return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z');
 }
+static inline int ctype_toupper(int c) {
+  return ctype_alpha(c) ? (c & ~32) : c;
+}
 static inline int ctype_822special(int c) {
   return strchr("()<>@,;:\\\".[]",c) != 0;
 }
diff --git a/src/parse.c b/src/parse.c
index 1d5a993..20853dd 100644
--- a/src/parse.c
+++ b/src/parse.c
@@ -160,7 +160,17 @@ adns_status adns__parse_domain_more(findlabel_state *fls, adns_state ads,
   if (!adns__vbuf_append(vb,"",1)) return adns_s_nomemory;
   return adns_s_ok;
 }
-	
+
+bool adns__labels_equal(const byte *a, int al, const byte *b, int bl) {
+  if (al != bl) return 0;
+  while (al-- > 0) {
+    int ac= ctype_toupper(*a++);
+    int bc= ctype_toupper(*b++);
+    if (ac != bc) return 0;
+  }
+  return 1;
+}
+
 adns_status adns__findrr_anychk(adns_query qu, int serv,
 				const byte *dgram, int dglen, int *cbyte_io,
 				int *type_r, int *class_r,
@@ -174,8 +184,8 @@ adns_status adns__findrr_anychk(adns_query qu, int serv,
   
   int tmp, rdlen;
   unsigned long ttl;
-  int lablen, labstart, ch;
-  int eo_lablen, eo_labstart, eo_ch;
+  int lablen, labstart;
+  int eo_lablen, eo_labstart;
   adns_status st;
 
   cbyte= *cbyte_io;
@@ -197,12 +207,9 @@ adns_status adns__findrr_anychk(adns_query qu, int serv,
     if (eo_fls) {
       st= adns__findlabel_next(eo_fls,&eo_lablen,&eo_labstart);
       assert(!st); assert(eo_lablen>=0);
-      if (lablen != eo_lablen) eo_fls= 0;
-      while (eo_fls && eo_lablen-- > 0) {
-	ch= dgram[labstart++]; if (ctype_alpha(ch)) ch &= ~32;
-	eo_ch= eo_dgram[eo_labstart++]; if (ctype_alpha(eo_ch)) eo_ch &= ~32;
-	if (ch != eo_ch) eo_fls= 0;
-      }
+      if (!adns__labels_equal(dgram+labstart, lablen,
+			      eo_dgram+eo_labstart, eo_lablen))
+	eo_fls= 0;
     }
     if (!lablen) break;
   }