dns: remove some magic numbers

Let's use enum values for the EDNS codes now that we have them, for
readability.

diff --git a/src/resolve/resolved-dns-packet.c b/src/resolve/resolved-dns-packet.c
index 3729bef1ae5a4e4df6fb15f57da11918865c7cb4..8eb75082cd33088f8fee65369871c7da7cddfcf0 100644 (file)
--- a/src/resolve/resolved-dns-packet.c
+++ b/src/resolve/resolved-dns-packet.c
@@ -775,7 +775,7 @@ int dns_packet_append_opt(
 
                 static const uint8_t rfc6975[] = {
 
-                        0, 5, /* OPTION_CODE: DAU */
+                        0, DNS_EDNS_OPT_DAU, /* OPTION_CODE */
 #if PREFER_OPENSSL || (HAVE_GCRYPT && GCRYPT_VERSION_NUMBER >= 0x010600)
                         0, 7, /* LIST_LENGTH */
 #else
@@ -791,13 +791,13 @@ int dns_packet_append_opt(
                         DNSSEC_ALGORITHM_ED25519,
 #endif
 
-                        0, 6, /* OPTION_CODE: DHU */
+                        0, DNS_EDNS_OPT_DHU, /* OPTION_CODE */
                         0, 3, /* LIST_LENGTH */
                         DNSSEC_DIGEST_SHA1,
                         DNSSEC_DIGEST_SHA256,
                         DNSSEC_DIGEST_SHA384,
 
-                        0, 7, /* OPTION_CODE: N3U */
+                        0, DNS_EDNS_OPT_N3U, /* OPTION_CODE */
                         0, 1, /* LIST_LENGTH */
                         NSEC3_ALGORITHM_SHA1,
                 };
@@ -2180,7 +2180,7 @@ static bool opt_is_good(DnsResourceRecord *rr, bool *rfc6975) {
                         return false;
 
                 /* RFC 6975 DAU, DHU or N3U fields found. */
-                if (IN_SET(option_code, 5, 6, 7))
+                if (IN_SET(option_code, DNS_EDNS_OPT_DAU, DNS_EDNS_OPT_DHU, DNS_EDNS_OPT_N3U))
                         found_dau_dhu_n3u = true;
 
                 p += option_length + 4U;
@@ -2597,7 +2597,7 @@ int dns_packet_has_nsid_request(DnsPacket *p) {
                         return log_debug_errno(SYNTHETIC_ERRNO(EBADMSG),
                                                "Truncated option in EDNS0 variable part.");
 
-                if (code == 3) {
+                if (code == DNS_EDNS_OPT_NSID) {
                         if (has_nsid)
                                 return log_debug_errno(SYNTHETIC_ERRNO(EBADMSG),
                                                        "Duplicate NSID option in EDNS0 variable part.");