1 files changed, 43 insertions, 0 deletions
diff --git a/src/dnsstub/dns_dtda.c b/src/dnsstub/dns_dtda.c
new file mode 100644
index 0000000..38358a2
--- /dev/null
+++ b/src/dnsstub/dns_dtda.c
@@ -0,0 +1,43 @@
+#include "stralloc.h"
+#include "dnsresolv.h"
+
+/**
+	@file dns_dtda.c
+	@author djb
+	@source ucspi-tcp
+	@brief domain to dot append
+*/
+
+int dns_domain_todot_cat(stralloc *out,const char *d)
+{
+  char ch;
+  char ch2;
+  unsigned char ch3;
+  char buf[4];
+
+  if (!*d)
+    return stralloc_append(out,".");
+
+  for (;;) {
+    ch = *d++;
+    while (ch--) {
+      ch2 = *d++;
+      if ((ch2 >= 'A') && (ch2 <= 'Z')) ch2 += 32;   // FQDN -> lowercase
+      if (((ch2 >= 'a') && (ch2 <= 'z')) || 
+          ((ch2 >= '0') && (ch2 <= '9')) || 
+           (ch2 == '-') || (ch2 == '_')) {
+        if (!stralloc_append(out,&ch2)) return DNS_MEM;
+      }
+      else {                                         // decimal -> octal
+        ch3 = ch2;
+        buf[3] = '0' + (ch3 & 7); ch3 >>= 3;
+        buf[2] = '0' + (ch3 & 7); ch3 >>= 3;
+        buf[1] = '0' + (ch3 & 7);
+        buf[0] = '\\';
+        if (!stralloc_catb(out,buf,4)) return DNS_MEM;
+      }
+    }
+    if (!*d) return 1;
+    if (!stralloc_append(out,".")) return DNS_MEM;
+  }
+}