Patch Ubuntu netqmail-1.06 to handle DNS packets >512 byte and remove unneeded CNAME checks

0004-oversize-dns.diff

--- qmail-1.03/dns.c.103	Mon Aug 17 16:06:58 1998
+++ qmail-1.03/dns.c	Wed Aug 26 16:28:56 1998
@@ -21,10 +21,12 @@
 static unsigned short getshort(c) unsigned char *c;
 { unsigned short u; u = c[0]; return (u << 8) + c[1]; }

-static union { HEADER hdr; unsigned char buf[PACKETSZ]; } response;
+static struct { unsigned char *buf; } response;
+static int responsebuflen = 0;
 static int responselen;
 static unsigned char *responseend;
 static unsigned char *responsepos;
+static u_long saveresoptions;

 static int numanswers;
 static char name[MAXDNAME];
@@ -45,18 +47,33 @@
  errno = 0;
  if (!stralloc_copy(&glue,domain)) return DNS_MEM;
  if (!stralloc_0(&glue)) return DNS_MEM;
- responselen = lookup(glue.s,C_IN,type,response.buf,sizeof(response));
+ if (!responsebuflen)
+  if (response.buf = (unsigned char *)alloc(PACKETSZ+1))
+   responsebuflen = PACKETSZ+1;
+  else return DNS_MEM;
+
+ responselen = lookup(glue.s,C_IN,type,response.buf,responsebuflen);
+ if ((responselen >= responsebuflen) ||
+     (responselen > 0 && (((HEADER *)response.buf)->tc)))
+  {
+   if (responsebuflen < 65536)
+    if (alloc_re(&response.buf, responsebuflen, 65536))
+     responsebuflen = 65536;
+    else return DNS_MEM;
+    saveresoptions = _res.options;
+    _res.options |= RES_USEVC;
+    responselen = lookup(glue.s,C_IN,type,response.buf,responsebuflen);
+    _res.options = saveresoptions;
+  }
  if (responselen <= 0)
   {
    if (errno == ECONNREFUSED) return DNS_SOFT;
    if (h_errno == TRY_AGAIN) return DNS_SOFT;
    return DNS_HARD;
   }
- if (responselen >= sizeof(response))
-   responselen = sizeof(response);
  responseend = response.buf + responselen;
  responsepos = response.buf + sizeof(HEADER);
- n = ntohs(response.hdr.qdcount);
+ n = ntohs(((HEADER *)response.buf)->qdcount);
  while (n-- > 0)
   {
    i = dn_expand(response.buf,responseend,responsepos,name,MAXDNAME);
@@ -66,7 +83,7 @@
    if (i < QFIXEDSZ) return DNS_SOFT;
    responsepos += QFIXEDSZ;
   }
- numanswers = ntohs(response.hdr.ancount);
+ numanswers = ntohs(((HEADER *)response.buf)->ancount);
  return 0;
 }

0005-remove-cname-check.diff

--- netqmail-1.06/dns.c~	2014-11-09 21:30:43.000000000 +0100
+++ netqmail-1.06/dns.c	2014-11-09 21:32:36.954314782 +0100
@@ -204,32 +204,7 @@
 int dns_cname(sa)
 stralloc *sa;
 {
- int r;
- int loop;
- for (loop = 0;loop < 10;++loop)
-  {
-   if (!sa->len) return loop;
-   if (sa->s[sa->len - 1] == ']') return loop;
-   if (sa->s[sa->len - 1] == '.') { --sa->len; continue; }
-   switch(resolve(sa,T_ANY))
-    {
-     case DNS_MEM: return DNS_MEM;
-     case DNS_SOFT: return DNS_SOFT;
-     case DNS_HARD: return loop;
-     default:
-       while ((r = findname(T_CNAME)) != 2)
-	{
-	 if (r == DNS_SOFT) return DNS_SOFT;
-	 if (r == 1)
-	  {
-	   if (!stralloc_copys(sa,name)) return DNS_MEM;
-	   break;
-	  }
-	}
-       if (r == 2) return loop;
-    }
-  }
- return DNS_HARD; /* alias loop */
+ return 0;
 }

 #define FMT_IAA 40