[9.20] chg: dev: Use enum rather than numbers for isc_base64_tobuffer and isc_hex_tobuffer

Use isc_one_or_more and isc_zero_or_more rather than (-2) and
(-1) when calling isc_base64_tobuffer. Similarly for
isc_hex_tobuffer. This should help reduce the probability
that the wrong number is used and it makes the intent clearer.

Closes #5713

Backport of MR !11479

Merge branch 'backport-5713-use-macros-with-isc_base64_tobuffer-and-isc_hex_tobuffer-9.20' into 'bind-9.20'

See merge request isc-projects/bind9!11498

cocci/isc_x_tobuffer.spatch

@@ -0,0 +1,24 @@
+@@
+expression E1, E2;
+@@
+isc_base64_tobuffer
+-(E1, E2, -1)
++(E1, E2, isc_zero_or_more)
+@@
+expression E1, E2;
+@@
+isc_base64_tobuffer
+-(E1, E2, -2)
++(E1, E2, isc_one_or_more)
+@@
+expression E1, E2;
+@@
+isc_hex_tobuffer
+-(E1, E2, -1)
++(E1, E2, isc_zero_or_more)
+@@
+expression E1, E2;
+@@
+isc_hex_tobuffer
+-(E1, E2, -2)
++(E1, E2, isc_one_or_more)

lib/dns/dst_parse.c

@@ -549,7 +549,7 @@ 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;

lib/dns/rdata/generic/brid_68.c

@@ -28,7 +28,7 @@ fromtext_brid(ARGS_FROMTEXT) {
 	UNUSED(options);
 	UNUSED(callbacks);
 
-	return isc_base64_tobuffer(lexer, target, -2);
+	return isc_base64_tobuffer(lexer, target, isc_one_or_more);
 }
 
 static isc_result_t

lib/dns/rdata/generic/cert_37.c

@@ -58,7 +58,7 @@ fromtext_cert(ARGS_FROMTEXT) {
 	RETTOK(dns_secalg_fromtext(&secalg, &token.value.as_textregion));
 	RETERR(mem_tobuffer(target, &secalg, 1));
 
-	return isc_base64_tobuffer(lexer, target, -2);
+	return isc_base64_tobuffer(lexer, target, isc_one_or_more);
 }
 
 static isc_result_t

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);
 	}
 }
 

lib/dns/rdata/generic/hhit_67.c

@@ -28,7 +28,7 @@ fromtext_hhit(ARGS_FROMTEXT) {
 	UNUSED(options);
 	UNUSED(callbacks);
 
-	return isc_base64_tobuffer(lexer, target, -2);
+	return isc_base64_tobuffer(lexer, target, isc_one_or_more);
 }
 
 static isc_result_t

lib/dns/rdata/generic/ipseckey_45.c

@@ -118,7 +118,7 @@ fromtext_ipseckey(ARGS_FROMTEXT) {
 	/*
 	 * Public key.
 	 */
-	return isc_base64_tobuffer(lexer, target, -2);
+	return isc_base64_tobuffer(lexer, target, isc_one_or_more);
 }
 
 static isc_result_t

lib/dns/rdata/generic/key_25.c

@@ -89,7 +89,7 @@ generic_fromtext_key(ARGS_FROMTEXT) {
 	 */
 	used = isc_buffer_usedlength(target);
 
-	RETERR(isc_base64_tobuffer(lexer, target, -2));
+	RETERR(isc_base64_tobuffer(lexer, target, isc_one_or_more));
 
 	if (alg == DNS_KEYALG_PRIVATEDNS || alg == DNS_KEYALG_PRIVATEOID) {
 		isc_buffer_t b;

lib/dns/rdata/generic/keydata_65533.c

@@ -83,7 +83,7 @@ fromtext_keydata(ARGS_FROMTEXT) {
 		return ISC_R_SUCCESS;
 	}
 
-	return isc_base64_tobuffer(lexer, target, -2);
+	return isc_base64_tobuffer(lexer, target, isc_one_or_more);
 }
 
 static isc_result_t

lib/dns/rdata/generic/openpgpkey_61.c

@@ -29,7 +29,7 @@ fromtext_openpgpkey(ARGS_FROMTEXT) {
 	/*
 	 * Keyring.
 	 */
-	return isc_base64_tobuffer(lexer, target, -2);
+	return isc_base64_tobuffer(lexer, target, isc_one_or_more);
 }
 
 static isc_result_t

lib/dns/rdata/generic/rrsig_46.c

@@ -157,7 +157,7 @@ fromtext_rrsig(ARGS_FROMTEXT) {
 	 */
 	used = isc_buffer_usedlength(target);
 
-	RETERR(isc_base64_tobuffer(lexer, target, -2));
+	RETERR(isc_base64_tobuffer(lexer, target, isc_one_or_more));
 
 	if (alg == DNS_KEYALG_PRIVATEDNS || alg == DNS_KEYALG_PRIVATEOID) {
 		isc_buffer_t b;

lib/dns/rdata/generic/sig_24.c

@@ -121,7 +121,7 @@ fromtext_sig(ARGS_FROMTEXT) {
 	 */
 	used = isc_buffer_usedlength(target);
 
-	RETERR(isc_base64_tobuffer(lexer, target, -2));
+	RETERR(isc_base64_tobuffer(lexer, target, isc_one_or_more));
 
 	if (alg == DNS_KEYALG_PRIVATEDNS || alg == DNS_KEYALG_PRIVATEOID) {
 		isc_buffer_t 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

lib/dns/rdata/generic/tlsa_52.c

@@ -61,7 +61,7 @@ generic_fromtext_tlsa(ARGS_FROMTEXT) {
 	/*
 	 * Certificate Association Data.
 	 */
-	return isc_hex_tobuffer(lexer, target, -2);
+	return isc_hex_tobuffer(lexer, target, isc_one_or_more);
 }
 
 static isc_result_t

lib/dns/rdata/in_1/dhcid_49.c

@@ -29,7 +29,7 @@ fromtext_in_dhcid(ARGS_FROMTEXT) {
 	UNUSED(options);
 	UNUSED(callbacks);
 
-	return isc_base64_tobuffer(lexer, target, -2);
+	return isc_base64_tobuffer(lexer, target, isc_one_or_more);
 }
 
 static isc_result_t

lib/dns/rdata/in_1/eid_31.c

@@ -29,7 +29,7 @@ fromtext_in_eid(ARGS_FROMTEXT) {
 	UNUSED(rdclass);
 	UNUSED(callbacks);
 
-	return isc_hex_tobuffer(lexer, target, -2);
+	return isc_hex_tobuffer(lexer, target, isc_one_or_more);
 }
 
 static isc_result_t

lib/dns/rdata/in_1/nimloc_32.c

@@ -29,7 +29,7 @@ fromtext_in_nimloc(ARGS_FROMTEXT) {
 	UNUSED(rdclass);
 	UNUSED(callbacks);
 
-	return isc_hex_tobuffer(lexer, target, -2);
+	return isc_hex_tobuffer(lexer, target, isc_one_or_more);
 }
 
 static isc_result_t

lib/isc/base64.c

@@ -179,7 +179,7 @@ isc_base64_tobuffer(isc_lex_t *lexer, isc_buffer_t *target, int length) {
 	isc_token_t token;
 	bool eol;
 
-	REQUIRE(length >= -2);
+	REQUIRE(length >= isc_one_or_more);
 
 	base64_decode_init(&ctx, length, target);
 
@@ -207,7 +207,7 @@ isc_base64_tobuffer(isc_lex_t *lexer, isc_buffer_t *target, int length) {
 		isc_lex_ungettoken(lexer, &token);
 	}
 	RETERR(base64_decode_finish(&ctx));
-	if (length == -2 && before == after) {
+	if (length == isc_one_or_more && before == after) {
 		return ISC_R_UNEXPECTEDEND;
 	}
 	return ISC_R_SUCCESS;
@@ -217,7 +217,7 @@ isc_result_t
 isc_base64_decodestring(const char *cstr, isc_buffer_t *target) {
 	base64_decode_ctx_t ctx;
 
-	base64_decode_init(&ctx, -1, target);
+	base64_decode_init(&ctx, isc_zero_or_more, target);
 	for (;;) {
 		int c = *cstr++;
 		if (c == '\0') {

lib/isc/hex.c

@@ -138,7 +138,7 @@ isc_hex_tobuffer(isc_lex_t *lexer, isc_buffer_t *target, int length) {
 	isc_token_t token;
 	bool eol;
 
-	REQUIRE(length >= -2);
+	REQUIRE(length >= isc_one_or_more);
 
 	hex_decode_init(&ctx, length, target);
 
@@ -166,7 +166,7 @@ isc_hex_tobuffer(isc_lex_t *lexer, isc_buffer_t *target, int length) {
 		isc_lex_ungettoken(lexer, &token);
 	}
 	RETERR(hex_decode_finish(&ctx));
-	if (length == -2 && before == after) {
+	if (length == isc_one_or_more && before == after) {
 		return ISC_R_UNEXPECTEDEND;
 	}
 	return ISC_R_SUCCESS;
@@ -176,7 +176,7 @@ isc_result_t
 isc_hex_decodestring(const char *cstr, isc_buffer_t *target) {
 	hex_decode_ctx_t ctx;
 
-	hex_decode_init(&ctx, -1, target);
+	hex_decode_init(&ctx, isc_zero_or_more, target);
 	for (;;) {
 		int c = *cstr++;
 		if (c == '\0') {

lib/isc/include/isc/base64.h

@@ -75,8 +75,11 @@ isc_base64_tobuffer(isc_lex_t *lexer, isc_buffer_t *target, int length);
  * `target`. If 'length' is non-negative, it is the expected number of
  * encoded octets to convert.
  *
- * If 'length' is -1 then 0 or more encoded octets are expected.
- * If 'length' is -2 then 1 or more encoded octets are expected.
+ * If 'length' is isc_zero_or_more then 0 or more encoded octets are
+ * expected.
+ *
+ * If 'length' is isc_one_or_more then 1 or more encoded octets are
+ * expected.
  *
  * Returns:
  *\li	#ISC_R_BADBASE64 -- invalid base64 encoding.

lib/isc/include/isc/hex.h

@@ -88,8 +88,11 @@ isc_hex_tobuffer(isc_lex_t *lexer, isc_buffer_t *target, int length);
  * `target`. If 'length' is non-negative, it is the expected number of
  * encoded octets to convert.
  *
- * If 'length' is -1 then 0 or more encoded octets are expected.
- * If 'length' is -2 then 1 or more encoded octets are expected.
+ * If 'length' is isc_zero_or_more then 0 or more encoded octets are
+ * expected.
+ *
+ * If 'length' is isc_one_or_more then 1 or more encoded octets are
+ * expected.
  *
  * Returns:
  *\li	#ISC_R_BADHEX -- invalid hex encoding

lib/isc/include/isc/types.h

@@ -86,6 +86,12 @@ typedef struct isc_nm_http_endpoints isc_nm_http_endpoints_t;
 /*%< HTTP endpoints set */
 #endif /* HAVE_LIBNGHTTP2 */
 
+/*% Used by isc_base64 and isc_hex for expected lower bound */
+enum {
+	isc_zero_or_more = -1,
+	isc_one_or_more = -2,
+};
+
 /*% Statistics formats (text file or XML) */
 typedef enum {
 	isc_statsformat_file,