stream: track type of DnsStream object

We use stream objects in four different cases: let's track them.

This in particular allows us to make sure the limit on outgoing streams
cannot be exhausted by having incoming streams as this means we can
neatly separate the counters for all four types.

diff --git a/src/resolve/resolved-dns-stream.c b/src/resolve/resolved-dns-stream.c
index e29c970d51697326d9fe49c1f2504de72c82ef2c..ebafaa529c72606cb3a7fc9267aab53bedb73d9b 100644 (file)
--- a/src/resolve/resolved-dns-stream.c
+++ b/src/resolve/resolved-dns-stream.c
@@ -437,7 +437,7 @@ static DnsStream *dns_stream_free(DnsStream *s) {
 
         if (s->manager) {
                 LIST_REMOVE(streams, s->manager->dns_streams, s);
-                s->manager->n_dns_streams--;
+                s->manager->n_dns_streams[s->type]--;
         }
 
 #if ENABLE_DNS_OVER_TLS
@@ -462,6 +462,7 @@ DEFINE_TRIVIAL_REF_UNREF_FUNC(DnsStream, dns_stream, dns_stream_free);
 int dns_stream_new(
                 Manager *m,
                 DnsStream **ret,
+                DnsStreamType type,
                 DnsProtocol protocol,
                 int fd,
                 const union sockaddr_union *tfo_address) {
@@ -471,9 +472,13 @@ int dns_stream_new(
 
         assert(m);
         assert(ret);
+        assert(type >= 0);
+        assert(type < _DNS_STREAM_TYPE_MAX);
+        assert(protocol >= 0);
+        assert(protocol < _DNS_PROTOCOL_MAX);
         assert(fd >= 0);
 
-        if (m->n_dns_streams > DNS_STREAMS_MAX)
+        if (m->n_dns_streams[type] > DNS_STREAMS_MAX)
                 return -EBUSY;
 
         s = new(DnsStream, 1);
@@ -508,7 +513,7 @@ int dns_stream_new(
         (void) sd_event_source_set_description(s->timeout_event_source, "dns-stream-timeout");
 
         LIST_PREPEND(streams, m->dns_streams, s);
-        m->n_dns_streams++;
+        m->n_dns_streams[type]++;
         s->manager = m;
 
         s->fd = fd;

diff --git a/src/resolve/resolved-dns-stream.h b/src/resolve/resolved-dns-stream.h
index f18fc919e7399ee81ea922b8df412c85cadab72b..2c6d9c00b9caaddea60541660a6698eb1dad55c6 100644 (file)
--- a/src/resolve/resolved-dns-stream.h
+++ b/src/resolve/resolved-dns-stream.h
@@ -5,6 +5,15 @@
 
 typedef struct DnsStream DnsStream;
 
+typedef enum DnsStreamType {
+        DNS_STREAM_LOOKUP,        /* Outgoing connection to a classic DNS server */
+        DNS_STREAM_LLMNR_SEND,    /* Outgoing LLMNR TCP lookup */
+        DNS_STREAM_LLMNR_RECV,    /* Incoming LLMNR TCP lookup */
+        DNS_STREAM_STUB,          /* Incoming DNS stub connection */
+        _DNS_STREAM_TYPE_MAX,
+        _DNS_STREAM_TYPE_INVALID = -1,
+} DnsStreamType;
+
 #include "resolved-dns-packet.h"
 #include "resolved-dns-transaction.h"
 #include "resolved-manager.h"
@@ -25,6 +34,7 @@ struct DnsStream {
         Manager *manager;
         unsigned n_ref;
 
+        DnsStreamType type;
         DnsProtocol protocol;
 
         int fd;
@@ -66,7 +76,7 @@ struct DnsStream {
         LIST_FIELDS(DnsStream, streams);
 };
 
-int dns_stream_new(Manager *m, DnsStream **s, DnsProtocol protocol, int fd, const union sockaddr_union *tfo_address);
+int dns_stream_new(Manager *m, DnsStream **s, DnsStreamType type, DnsProtocol protocol, int fd, const union sockaddr_union *tfo_address);
 #if ENABLE_DNS_OVER_TLS
 int dns_stream_connect_tls(DnsStream *s, void *tls_session);
 #endif

diff --git a/src/resolve/resolved-dns-stub.c b/src/resolve/resolved-dns-stub.c
index a00716cd857072344295911ebd8b09f462857a87..39ce42d1558386a32e8a3c34a4b60fbd80efde77 100644 (file)
--- a/src/resolve/resolved-dns-stub.c
+++ b/src/resolve/resolved-dns-stub.c
@@ -471,7 +471,7 @@ static int on_dns_stub_stream(sd_event_source *s, int fd, uint32_t revents, void
                 return -errno;
         }
 
-        r = dns_stream_new(m, &stream, DNS_PROTOCOL_DNS, cfd, NULL);
+        r = dns_stream_new(m, &stream, DNS_STREAM_STUB, DNS_PROTOCOL_DNS, cfd, NULL);
         if (r < 0) {
                 safe_close(cfd);
                 return r;

diff --git a/src/resolve/resolved-dns-transaction.c b/src/resolve/resolved-dns-transaction.c
index 4a2d2ccbde1498b1c0eae729796348ab20687240..075dfac01bd09bdaad7c4abe6b1736348bc49609 100644 (file)
--- a/src/resolve/resolved-dns-transaction.c
+++ b/src/resolve/resolved-dns-transaction.c
@@ -554,9 +554,10 @@ static uint16_t dns_port_for_feature_level(DnsServerFeatureLevel level) {
 }
 
 static int dns_transaction_emit_tcp(DnsTransaction *t) {
-        _cleanup_close_ int fd = -1;
         _cleanup_(dns_stream_unrefp) DnsStream *s = NULL;
+        _cleanup_close_ int fd = -1;
         union sockaddr_union sa;
+        DnsStreamType type;
         int r;
 
         assert(t);
@@ -582,6 +583,7 @@ static int dns_transaction_emit_tcp(DnsTransaction *t) {
                 else
                         fd = dns_scope_socket_tcp(t->scope, AF_UNSPEC, NULL, t->server, dns_port_for_feature_level(t->current_feature_level), &sa);
 
+                type = DNS_STREAM_LOOKUP;
                 break;
 
         case DNS_PROTOCOL_LLMNR:
@@ -607,6 +609,7 @@ static int dns_transaction_emit_tcp(DnsTransaction *t) {
                         fd = dns_scope_socket_tcp(t->scope, family, &address, NULL, LLMNR_PORT, &sa);
                 }
 
+                type = DNS_STREAM_LLMNR_SEND;
                 break;
 
         default:
@@ -617,7 +620,7 @@ static int dns_transaction_emit_tcp(DnsTransaction *t) {
                 if (fd < 0)
                         return fd;
 
-                r = dns_stream_new(t->scope->manager, &s, t->scope->protocol, fd, &sa);
+                r = dns_stream_new(t->scope->manager, &s, type, t->scope->protocol, fd, &sa);
                 if (r < 0)
                         return r;
 

diff --git a/src/resolve/resolved-llmnr.c b/src/resolve/resolved-llmnr.c
index dfa55c577c402a1575379ab0f74b041346830c45..d73f86560d00460ebddf92871b58ccd0fd76ae73 100644 (file)
--- a/src/resolve/resolved-llmnr.c
+++ b/src/resolve/resolved-llmnr.c
@@ -295,7 +295,7 @@ static int on_llmnr_stream(sd_event_source *s, int fd, uint32_t revents, void *u
                 return -errno;
         }
 
-        r = dns_stream_new(m, &stream, DNS_PROTOCOL_LLMNR, cfd, NULL);
+        r = dns_stream_new(m, &stream, DNS_STREAM_LLMNR_RECV, DNS_PROTOCOL_LLMNR, cfd, NULL);
         if (r < 0) {
                 safe_close(cfd);
                 return r;

diff --git a/src/resolve/resolved-manager.h b/src/resolve/resolved-manager.h
index 06c76f6014dc438cb669faeefed94f797c8753a8..72171f8c975b1dc8cb9292d997eab2011c821aab 100644 (file)
--- a/src/resolve/resolved-manager.h
+++ b/src/resolve/resolved-manager.h
@@ -54,7 +54,7 @@ struct Manager {
         unsigned n_dns_queries;
 
         LIST_HEAD(DnsStream, dns_streams);
-        unsigned n_dns_streams;
+        unsigned n_dns_streams[_DNS_STREAM_TYPE_MAX];
 
         /* Unicast dns */
         LIST_HEAD(DnsServer, dns_servers);