Merge pull request #1030 from zonque/resolve

resolve: minor cleanups

9 files changed, 117 insertions, 82 deletions

diff --git a/src/network/networkd-link.c b/src/network/networkd-link.c
index 91b9cdf30d..cc9dc393c6 100644
--- a/src/network/networkd-link.c
+++ b/src/network/networkd-link.c
@@ -2378,7 +2378,7 @@ int link_save(Link *link) {
                         yes_no(link->network->wildcard_domain));
 
                 fprintf(f, "LLMNR=%s\n",
-                        llmnr_support_to_string(link->network->llmnr));
+                        resolve_support_to_string(link->network->llmnr));
         }
 
         if (!hashmap_isempty(link->bound_to_links)) {
diff --git a/src/network/networkd-network-gperf.gperf b/src/network/networkd-network-gperf.gperf
index 8735b39581..7ac7ef1ea3 100644
--- a/src/network/networkd-network-gperf.gperf
+++ b/src/network/networkd-network-gperf.gperf
@@ -45,7 +45,7 @@ Network.Address,               config_parse_address,                           0
 Network.Gateway,               config_parse_gateway,                           0,                             0
 Network.Domains,               config_parse_domains,                           0,                             offsetof(Network, domains)
 Network.DNS,                   config_parse_strv,                              0,                             offsetof(Network, dns)
-Network.LLMNR,                 config_parse_llmnr,                             0,                             offsetof(Network, llmnr)
+Network.LLMNR,                 config_parse_resolve,                           0,                             offsetof(Network, llmnr)
 Network.NTP,                   config_parse_strv,                              0,                             offsetof(Network, ntp)
 Network.IPForward,             config_parse_address_family_boolean_with_kernel,0,                             offsetof(Network, ip_forward)
 Network.IPMasquerade,          config_parse_bool,                              0,                             offsetof(Network, ip_masquerade)
diff --git a/src/network/networkd-network.c b/src/network/networkd-network.c
index 3f7e77da3e..6587ea994c 100644
--- a/src/network/networkd-network.c
+++ b/src/network/networkd-network.c
@@ -111,7 +111,7 @@ static int network_load_one(Manager *manager, const char *filename) {
         network->allow_port_to_be_root = true;
         network->unicast_flood = true;
 
-        network->llmnr = LLMNR_SUPPORT_YES;
+        network->llmnr = RESOLVE_SUPPORT_YES;
 
         network->link_local = ADDRESS_FAMILY_IPV6;
 
@@ -632,15 +632,15 @@ static const char* const dhcp_client_identifier_table[_DHCP_CLIENT_ID_MAX] = {
 DEFINE_PRIVATE_STRING_TABLE_LOOKUP_FROM_STRING(dhcp_client_identifier, DCHPClientIdentifier);
 DEFINE_CONFIG_PARSE_ENUM(config_parse_dhcp_client_identifier, dhcp_client_identifier, DCHPClientIdentifier, "Failed to parse client identifier type");
 
-static const char* const llmnr_support_table[_LLMNR_SUPPORT_MAX] = {
-        [LLMNR_SUPPORT_NO] = "no",
-        [LLMNR_SUPPORT_YES] = "yes",
-        [LLMNR_SUPPORT_RESOLVE] = "resolve",
+static const char* const resolve_support_table[_RESOLVE_SUPPORT_MAX] = {
+        [RESOLVE_SUPPORT_NO] = "no",
+        [RESOLVE_SUPPORT_YES] = "yes",
+        [RESOLVE_SUPPORT_RESOLVE] = "resolve",
 };
 
-DEFINE_STRING_TABLE_LOOKUP(llmnr_support, LLMNRSupport);
+DEFINE_STRING_TABLE_LOOKUP(resolve_support, ResolveSupport);
 
-int config_parse_llmnr(
+int config_parse_resolve(
                 const char* unit,
                 const char *filename,
                 unsigned line,
@@ -652,32 +652,32 @@ int config_parse_llmnr(
                 void *data,
                 void *userdata) {
 
-        LLMNRSupport *llmnr = data;
+        ResolveSupport *resolve = data;
         int k;
 
         assert(filename);
         assert(lvalue);
         assert(rvalue);
-        assert(llmnr);
+        assert(resolve);
 
         /* Our enum shall be a superset of booleans, hence first try
          * to parse as boolean, and then as enum */
 
         k = parse_boolean(rvalue);
         if (k > 0)
-                *llmnr = LLMNR_SUPPORT_YES;
+                *resolve = RESOLVE_SUPPORT_YES;
         else if (k == 0)
-                *llmnr = LLMNR_SUPPORT_NO;
+                *resolve = RESOLVE_SUPPORT_NO;
         else {
-                LLMNRSupport s;
+                ResolveSupport s;
 
-                s = llmnr_support_from_string(rvalue);
+                s = resolve_support_from_string(rvalue);
                 if (s < 0){
-                        log_syntax(unit, LOG_ERR, filename, line, -s, "Failed to parse LLMNR option, ignoring: %s", rvalue);
+                        log_syntax(unit, LOG_ERR, filename, line, -s, "Failed to parse %s option, ignoring: %s", lvalue, rvalue);
                         return 0;
                 }
 
-                *llmnr = s;
+                *resolve = s;
         }
 
         return 0;
diff --git a/src/network/networkd.h b/src/network/networkd.h
index a285a4b08f..5340922bf1 100644
--- a/src/network/networkd.h
+++ b/src/network/networkd.h
@@ -64,13 +64,13 @@ typedef enum AddressFamilyBoolean {
         _ADDRESS_FAMILY_BOOLEAN_INVALID = -1,
 } AddressFamilyBoolean;
 
-typedef enum LLMNRSupport {
-        LLMNR_SUPPORT_NO,
-        LLMNR_SUPPORT_YES,
-        LLMNR_SUPPORT_RESOLVE,
-        _LLMNR_SUPPORT_MAX,
-        _LLMNR_SUPPORT_INVALID = -1,
-} LLMNRSupport;
+typedef enum ResolveSupport {
+        RESOLVE_SUPPORT_NO,
+        RESOLVE_SUPPORT_YES,
+        RESOLVE_SUPPORT_RESOLVE,
+        _RESOLVE_SUPPORT_MAX,
+        _RESOLVE_SUPPORT_INVALID = -1,
+} ResolveSupport;
 
 typedef enum LinkOperationalState {
         LINK_OPERSTATE_OFF,
@@ -178,7 +178,7 @@ struct Network {
         bool wildcard_domain;
         char **domains, **dns, **ntp, **bind_carrier;
 
-        LLMNRSupport llmnr;
+        ResolveSupport llmnr;
 
         LIST_FIELDS(Network, networks);
 };
@@ -421,14 +421,14 @@ int config_parse_ipv6token(const char *unit, const char *filename, unsigned line
                            const char *section, unsigned section_line, const char *lvalue,
                            int ltype, const char *rvalue, void *data, void *userdata);
 
-/* LLMNR support */
+/* Resolve protocols support */
 
-const char* llmnr_support_to_string(LLMNRSupport i) _const_;
-LLMNRSupport llmnr_support_from_string(const char *s) _pure_;
+const char* resolve_support_to_string(ResolveSupport i) _const_;
+ResolveSupport resolve_support_from_string(const char *s) _pure_;
 
-int config_parse_llmnr(const char *unit, const char *filename, unsigned line,
-                      const char *section, unsigned section_line, const char *lvalue,
-                      int ltype, const char *rvalue, void *data, void *userdata);
+int config_parse_resolve(const char *unit, const char *filename, unsigned line,
+                         const char *section, unsigned section_line, const char *lvalue,
+                         int ltype, const char *rvalue, void *data, void *userdata);
 
 /* Address Pool */
 
diff --git a/src/resolve/resolved-dns-cache.c b/src/resolve/resolved-dns-cache.c
index efc407dbc6..7ee098397c 100644
--- a/src/resolve/resolved-dns-cache.c
+++ b/src/resolve/resolved-dns-cache.c
@@ -411,16 +411,17 @@ int dns_cache_put(
                 int owner_family,
                 const union in_addr_union *owner_address) {
 
-        unsigned i;
+        unsigned cache_keys, i;
         int r;
 
         assert(c);
-        assert(q);
 
-        /* First, delete all matching old RRs, so that we only keep
-         * complete by_key in place. */
-        for (i = 0; i < q->n_keys; i++)
-                dns_cache_remove(c, q->keys[i]);
+        if (q) {
+                /* First, if we were passed a question, delete all matching old RRs,
+                 * so that we only keep complete by_key in place. */
+                for (i = 0; i < q->n_keys; i++)
+                        dns_cache_remove(c, q->keys[i]);
+        }
 
         if (!answer)
                 return 0;
@@ -435,8 +436,13 @@ int dns_cache_put(
         if (!IN_SET(rcode, DNS_RCODE_SUCCESS, DNS_RCODE_NXDOMAIN))
                 return 0;
 
+        cache_keys = answer->n_rrs;
+
+        if (q)
+                cache_keys += q->n_keys;
+
         /* Make some space for our new entries */
-        dns_cache_make_space(c, answer->n_rrs + q->n_keys);
+        dns_cache_make_space(c, cache_keys);
 
         if (timestamp <= 0)
                 timestamp = now(clock_boottime_or_monotonic());
@@ -448,6 +454,9 @@ int dns_cache_put(
                         goto fail;
         }
 
+        if (!q)
+                return 0;
+
         /* Third, add in negative entries for all keys with no RR */
         for (i = 0; i < q->n_keys; i++) {
                 DnsResourceRecord *soa = NULL;
@@ -479,8 +488,11 @@ fail:
         /* Adding all RRs failed. Let's clean up what we already
          * added, just in case */
 
-        for (i = 0; i < q->n_keys; i++)
-                dns_cache_remove(c, q->keys[i]);
+        if (q) {
+                for (i = 0; i < q->n_keys; i++)
+                        dns_cache_remove(c, q->keys[i]);
+        }
+
         for (i = 0; i < answer->n_rrs; i++)
                 dns_cache_remove(c, answer->items[i].rr->key);
 
diff --git a/src/resolve/resolved-dns-packet.c b/src/resolve/resolved-dns-packet.c
index bebd1ee4a6..784d949cce 100644
--- a/src/resolve/resolved-dns-packet.c
+++ b/src/resolve/resolved-dns-packet.c
@@ -64,7 +64,7 @@ int dns_packet_new(DnsPacket **ret, DnsProtocol protocol, size_t mtu) {
 int dns_packet_new_query(DnsPacket **ret, DnsProtocol protocol, size_t mtu) {
         DnsPacket *p;
         DnsPacketHeader *h;
-        int r;
+        int r, rd;
 
         assert(ret);
 
@@ -74,26 +74,27 @@ int dns_packet_new_query(DnsPacket **ret, DnsProtocol protocol, size_t mtu) {
 
         h = DNS_PACKET_HEADER(p);
 
-        if (protocol == DNS_PROTOCOL_LLMNR)
-                h->flags = htobe16(DNS_PACKET_MAKE_FLAGS(0 /* qr */,
-                                                         0 /* opcode */,
-                                                         0 /* c */,
-                                                         0 /* tc */,
-                                                         0 /* t */,
-                                                         0 /* ra */,
-                                                         0 /* ad */,
-                                                         0 /* cd */,
-                                                         0 /* rcode */));
-        else
-                h->flags = htobe16(DNS_PACKET_MAKE_FLAGS(0 /* qr */,
-                                                         0 /* opcode */,
-                                                         0 /* aa */,
-                                                         0 /* tc */,
-                                                         1 /* rd (ask for recursion) */,
-                                                         0 /* ra */,
-                                                         0 /* ad */,
-                                                         0 /* cd */,
-                                                         0 /* rcode */));
+        switch (protocol) {
+        case DNS_PROTOCOL_LLMNR:
+                /* no recursion for link-local resolving protocols */
+                rd = 0;
+                break;
+
+        default:
+                /* ask for recursion */
+                rd = 1;
+                break;
+        }
+
+        h->flags = htobe16(DNS_PACKET_MAKE_FLAGS(0  /* qr */,
+                                                 0  /* opcode */,
+                                                 0  /* aa */,
+                                                 0  /* tc */,
+                                                 rd /* rd */,
+                                                 0  /* ra */,
+                                                 0  /* ad */,
+                                                 0  /* cd */,
+                                                 0  /* rcode */));
 
         *ret = p;
         return 0;
diff --git a/src/resolve/resolved-dns-packet.h b/src/resolve/resolved-dns-packet.h
index e81f8a8202..8a72b898da 100644
--- a/src/resolve/resolved-dns-packet.h
+++ b/src/resolve/resolved-dns-packet.h
@@ -239,11 +239,16 @@ static inline uint64_t SD_RESOLVED_FLAGS_MAKE(DnsProtocol protocol, int family)
 
         /* Converts a protocol + family into a flags field as used in queries */
 
-        if (protocol == DNS_PROTOCOL_DNS)
+        switch (protocol) {
+        case DNS_PROTOCOL_DNS:
                 return SD_RESOLVED_DNS;
 
-        if (protocol == DNS_PROTOCOL_LLMNR)
+        case DNS_PROTOCOL_LLMNR:
                 return family == AF_INET6 ? SD_RESOLVED_LLMNR_IPV6 : SD_RESOLVED_LLMNR_IPV4;
 
+        default:
+                break;
+        }
+
         return 0;
 }
diff --git a/src/resolve/resolved-dns-scope.c b/src/resolve/resolved-dns-scope.c
index 336269ca8a..77034a0be8 100644
--- a/src/resolve/resolved-dns-scope.c
+++ b/src/resolve/resolved-dns-scope.c
@@ -166,7 +166,8 @@ int dns_scope_emit(DnsScope *s, int fd, DnsPacket *p) {
         } else
                 mtu = manager_find_mtu(s->manager);
 
-        if (s->protocol == DNS_PROTOCOL_DNS) {
+        switch (s->protocol) {
+        case DNS_PROTOCOL_DNS:
                 if (DNS_PACKET_QDCOUNT(p) > 1)
                         return -EOPNOTSUPP;
 
@@ -180,8 +181,9 @@ int dns_scope_emit(DnsScope *s, int fd, DnsPacket *p) {
                 if (r < 0)
                         return r;
 
-        } else if (s->protocol == DNS_PROTOCOL_LLMNR) {
+                break;
 
+        case DNS_PROTOCOL_LLMNR:
                 if (DNS_PACKET_QDCOUNT(p) > 1)
                         return -EOPNOTSUPP;
 
@@ -205,8 +207,12 @@ int dns_scope_emit(DnsScope *s, int fd, DnsPacket *p) {
                 r = manager_send(s->manager, fd, ifindex, family, &addr, port, p);
                 if (r < 0)
                         return r;
-        } else
+
+                break;
+
+        default:
                 return -EAFNOSUPPORT;
+        }
 
         return 1;
 }
@@ -341,27 +347,25 @@ DnsScopeMatch dns_scope_good_domain(DnsScope *s, int ifindex, uint64_t flags, co
                 if (dns_name_endswith(domain, *i) > 0)
                         return DNS_SCOPE_YES;
 
-        if (s->protocol == DNS_PROTOCOL_DNS) {
+        switch (s->protocol) {
+        case DNS_PROTOCOL_DNS:
                 if (dns_name_endswith(domain, "254.169.in-addr.arpa") == 0 &&
                     dns_name_endswith(domain, "0.8.e.f.ip6.arpa") == 0 &&
                     dns_name_single_label(domain) == 0)
                         return DNS_SCOPE_MAYBE;
 
                 return DNS_SCOPE_NO;
-        }
 
-        if (s->protocol == DNS_PROTOCOL_MDNS) {
+        case DNS_PROTOCOL_MDNS:
                 if ((s->family == AF_INET && dns_name_endswith(domain, "in-addr.arpa") > 0) ||
                     (s->family == AF_INET6 && dns_name_endswith(domain, "ip6.arpa") > 0) ||
                     (dns_name_endswith(domain, "local") > 0 && /* only resolve names ending in .local via mDNS */
                      dns_name_equal(domain, "local") == 0 &&   /* but not the single-label "local" name itself */
                      manager_is_own_hostname(s->manager, domain) <= 0)) /* never resolve the local hostname via mDNS */
-                        return DNS_SCOPE_MAYBE;
 
                 return DNS_SCOPE_NO;
-        }
 
-        if (s->protocol == DNS_PROTOCOL_LLMNR) {
+        case DNS_PROTOCOL_LLMNR:
                 if ((s->family == AF_INET && dns_name_endswith(domain, "in-addr.arpa") > 0) ||
                     (s->family == AF_INET6 && dns_name_endswith(domain, "ip6.arpa") > 0) ||
                     (dns_name_single_label(domain) > 0 && /* only resolve single label names via LLMNR */
@@ -370,9 +374,10 @@ DnsScopeMatch dns_scope_good_domain(DnsScope *s, int ifindex, uint64_t flags, co
                         return DNS_SCOPE_MAYBE;
 
                 return DNS_SCOPE_NO;
-        }
 
-        assert_not_reached("Unknown scope protocol");
+        default:
+                assert_not_reached("Unknown scope protocol");
+        }
 }
 
 int dns_scope_good_key(DnsScope *s, DnsResourceKey *key) {
diff --git a/src/resolve/resolved-dns-transaction.c b/src/resolve/resolved-dns-transaction.c
index bbbc6377a8..7b84c1bab8 100644
--- a/src/resolve/resolved-dns-transaction.c
+++ b/src/resolve/resolved-dns-transaction.c
@@ -186,9 +186,6 @@ void dns_transaction_complete(DnsTransaction *t, DnsTransactionState state) {
         assert(t);
         assert(!IN_SET(state, DNS_TRANSACTION_NULL, DNS_TRANSACTION_PENDING));
 
-        if (!IN_SET(t->state, DNS_TRANSACTION_NULL, DNS_TRANSACTION_PENDING))
-                return;
-
         /* Note that this call might invalidate the query. Callers
          * should hence not attempt to access the query or transaction
          * after calling this function. */
@@ -263,10 +260,12 @@ static int dns_transaction_open_tcp(DnsTransaction *t) {
         if (t->stream)
                 return 0;
 
-        if (t->scope->protocol == DNS_PROTOCOL_DNS)
+        switch (t->scope->protocol) {
+        case DNS_PROTOCOL_DNS:
                 fd = dns_scope_tcp_socket(t->scope, AF_UNSPEC, NULL, 53, &server);
-        else if (t->scope->protocol == DNS_PROTOCOL_LLMNR) {
+                break;
 
+        case DNS_PROTOCOL_LLMNR:
                 /* When we already received a reply to this (but it was truncated), send to its sender address */
                 if (t->received)
                         fd = dns_scope_tcp_socket(t->scope, t->received->family, &t->received->sender, t->received->sender_port, NULL);
@@ -288,8 +287,12 @@ static int dns_transaction_open_tcp(DnsTransaction *t) {
 
                         fd = dns_scope_tcp_socket(t->scope, family, &address, LLMNR_PORT, NULL);
                 }
-        } else
+
+                break;
+
+        default:
                 return -EAFNOSUPPORT;
+        }
 
         if (fd < 0)
                 return fd;
@@ -345,7 +348,8 @@ void dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p) {
          * should hence not attempt to access the query or transaction
          * after calling this function. */
 
-        if (t->scope->protocol == DNS_PROTOCOL_LLMNR) {
+        switch (t->scope->protocol) {
+        case DNS_PROTOCOL_LLMNR:
                 assert(t->scope->link);
 
                 /* For LLMNR we will not accept any packets from other
@@ -364,6 +368,14 @@ void dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p) {
                         dns_transaction_tentative(t, p);
                         return;
                 }
+
+                break;
+
+        case DNS_PROTOCOL_DNS:
+                break;
+
+        default:
+                assert_not_reached("Invalid DNS protocol.");
         }
 
         if (t->received != p) {
@@ -400,7 +412,7 @@ void dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p) {
 
                 break;
         default:
-                assert_not_reached("Invalid DNS protocol.");
+                break;
         }
 
         if (DNS_PACKET_TC(p)) {