diff --git a/lib/dns/dst_parse.c b/lib/dns/dst_parse.c
index 6a402c79e3..d058697ab4 100644
--- a/lib/dns/dst_parse.c
+++ b/lib/dns/dst_parse.c
@@ -554,7 +554,7 @@ dst__privstruct_parse(dst_key_t *key, unsigned int alg, isc_lex_t *lex,
 		data = isc_mem_get(mctx, MAXFIELDSIZE);
 
 		isc_buffer_init(&b, data, MAXFIELDSIZE);
-		CHECK(isc_base64_tobuffer(lex, &b, -1));
+		CHECK(isc_base64_tobuffer(lex, &b, isc_zero_or_more));
 
 		isc_buffer_usedregion(&b, &r);
 		priv->elements[n].length = r.length;
diff --git a/lib/dns/rdata/generic/doa_259.c b/lib/dns/rdata/generic/doa_259.c
index be926981f1..1398c782b6 100644
--- a/lib/dns/rdata/generic/doa_259.c
+++ b/lib/dns/rdata/generic/doa_259.c
@@ -67,7 +67,7 @@ fromtext_doa(ARGS_FROMTEXT) {
 		return ISC_R_SUCCESS;
 	} else {
 		isc_lex_ungettoken(lexer, &token);
-		return isc_base64_tobuffer(lexer, target, -1);
+		return isc_base64_tobuffer(lexer, target, isc_zero_or_more);
 	}
 }
 
diff --git a/lib/dns/rdata/generic/sink_40.c b/lib/dns/rdata/generic/sink_40.c
index 4ce1cf8808..0fb8aa5c07 100644
--- a/lib/dns/rdata/generic/sink_40.c
+++ b/lib/dns/rdata/generic/sink_40.c
@@ -54,7 +54,7 @@ fromtext_sink(ARGS_FROMTEXT) {
 	}
 	RETERR(uint8_tobuffer(token.value.as_ulong, target));
 
-	return isc_base64_tobuffer(lexer, target, -1);
+	return isc_base64_tobuffer(lexer, target, isc_zero_or_more);
 }
 
 static isc_result_t