diff --git a/ldif_parse.c b/ldif_parse.c
index 0ea49e5..509b131 100644
--- a/ldif_parse.c
+++ b/ldif_parse.c
@@ -110,8 +110,14 @@ nomem:
     uint32_t tmp, val;
     base64=binary=0;
     n=ofs+buffer_get_token(b,buf+ofs,8192-ofs,":",1);
-    if (n==0) break;
+    if (n==ofs) break;
     i=scan_whitenskip(buf,n);
+    if (buf[byte_chr(buf+i,n-i,'\n')]=='\n') {
+      buffer_puts(buffer_2,"LDIF parse error: no key:value in line ");
+      buffer_putulong(buffer_2,lines);
+      buffer_putnlflush(buffer_2);
+      exit(1);
+    }
     buf[n]=0;
     if ((i2=str_chr(buf,';'))<(unsigned int)n) {
       buf[i2]=0;
@@ -169,10 +175,23 @@ lookagain:
 	  }
 	  if (base64) {
 	    len=unbase64(payload.s);
+	    if (len==0) {
+	      buffer_puts(buffer_2,"LDIF parse error: base64 decoding failed in line ");
+	      buffer_putulong(buffer_2,lines);
+	      buffer_putnlflush(buffer_2);
+	      exit(1);
+	    }
 	    if (!binary) { payload.s[len]=0; ++len; }
 	  } else {
+	    size_t sl;
 	    len=n;
-	    scan_ldapescape(payload.s,payload.s,&len);
+	    sl=scan_ldapescape(payload.s,payload.s,&len);
+	    if (sl!=payload.len-1) {
+	      buffer_puts(buffer_2,"LDIF parse error: LDIF de-escaping failed in line ");
+	      buffer_putulong(buffer_2,lines);
+	      buffer_putnlflush(buffer_2);
+	      exit(1);
+	    }
 	    payload.s[len]=0;
 	    ++len;
 	  }
@@ -243,6 +262,12 @@ lookagain:
       }
       if (base64) {
 	len=unbase64(payload.s);
+	if (len==0) {
+	  buffer_puts(buffer_2,"LDIF parse error: base64 decoding failed in line ");
+	  buffer_putulong(buffer_2,lines);
+	  buffer_putnlflush(buffer_2);
+	  exit(1);
+	}
 	if (!binary) { payload.s[len]=0; ++len; }
       } else {
 	len=n;
diff --git a/tinyldap.c b/tinyldap.c
index fb0e49f..5d174ba 100644
--- a/tinyldap.c
+++ b/tinyldap.c
@@ -463,7 +463,7 @@ static int indexable(struct Filter* f) {
     }
     /* fall through */
   case PRESENT:
-    return 1;
+    return 0;
 #if 0
   /* doesn't make much sense to try to speed up negated queries */
   case NOT:
@@ -859,6 +859,8 @@ static int useindex(struct Filter* f,struct bitfield* b) {
     }
     return 0;
   case PRESENT:
+    return 0;
+#if 0
     {
       /* now this is not exactly using an index, but a linear search
        * through the record table, but since each check is very cheap,
@@ -873,6 +875,7 @@ static int useindex(struct Filter* f,struct bitfield* b) {
       }
       return 1;
     }
+#endif
   case LESSEQUAL:
   case GREATEQUAL:
   case EQUAL: