1 files changed, 135 insertions, 16 deletions

diff --git a/src/socket.c b/src/socket.c
index 2b3821190..d28df81a6 100644
--- a/src/socket.c
+++ b/src/socket.c
@@ -46,9 +46,10 @@ int sock_setreuse(int fd, int reuse) {
 
 int sock_setreuse_port(int fd, int reuse) {
     int ret = -1;
+
 #ifdef SO_REUSEPORT
     ret = setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &reuse, sizeof(reuse));
-    if(ret == -1)
+    if(ret == -1 && errno != ENOPROTOOPT)
         error("failed to set SO_REUSEPORT on socket %d", fd);
 #endif
 
@@ -80,6 +81,50 @@ int sock_enlarge_out(int fd) {
 // --------------------------------------------------------------------------------------------------------------------
 // listening sockets
 
+int create_listen_socket_unix(const char *path, int listen_backlog) {
+    int sock;
+
+    debug(D_LISTENER, "LISTENER: UNIX creating new listening socket on path '%s'", path);
+
+    sock = socket(AF_UNIX, SOCK_STREAM, 0);
+    if(sock < 0) {
+        error("LISTENER: UNIX socket() on path '%s' failed.", path);
+        return -1;
+    }
+
+    sock_setnonblock(sock);
+    sock_enlarge_in(sock);
+
+    struct sockaddr_un name;
+    memset(&name, 0, sizeof(struct sockaddr_un));
+    name.sun_family = AF_UNIX;
+    strncpy(name.sun_path, path, sizeof(name.sun_path)-1);
+
+    errno = 0;
+    if (unlink(path) == -1 && errno != ENOENT)
+        error("LISTENER: failed to remove existing (probably obsolete or left-over) file on UNIX socket path '%s'.", path);
+
+    if(bind (sock, (struct sockaddr *) &name, sizeof (name)) < 0) {
+        close(sock);
+        error("LISTENER: UNIX bind() on path '%s' failed.", path);
+        return -1;
+    }
+
+    // we have to chmod this to 0777 so that the client will be able
+    // to read from and write to this socket.
+    if(chmod(path, 0777) == -1)
+        error("LISTENER: failed to chmod() socket file '%s'.", path);
+
+    if(listen(sock, listen_backlog) < 0) {
+        close(sock);
+        error("LISTENER: UNIX listen() on path '%s' failed.", path);
+        return -1;
+    }
+
+    debug(D_LISTENER, "LISTENER: Listening on UNIX path '%s'", path);
+    return sock;
+}
+
 int create_listen_socket4(int socktype, const char *ip, int port, int listen_backlog) {
     int sock;
 
@@ -176,7 +221,7 @@ int create_listen_socket6(int socktype, uint32_t scope_id, const char *ip, int p
     return sock;
 }
 
-static inline int listen_sockets_add(LISTEN_SOCKETS *sockets, int fd, int socktype, const char *protocol, const char *ip, int port) {
+static inline int listen_sockets_add(LISTEN_SOCKETS *sockets, int fd, int family, int socktype, const char *protocol, const char *ip, int port) {
     if(sockets->opened >= MAX_LISTEN_FDS) {
         error("LISTENER: Too many listening sockets. Failed to add listening %s socket at ip '%s' port %d, protocol %s, socktype %d", protocol, ip, port, protocol, socktype);
         close(fd);
@@ -184,11 +229,27 @@ static inline int listen_sockets_add(LISTEN_SOCKETS *sockets, int fd, int sockty
     }
 
     sockets->fds[sockets->opened] = fd;
+    sockets->fds_types[sockets->opened] = socktype;
+    sockets->fds_families[sockets->opened] = family;
 
     char buffer[100 + 1];
-    snprintfz(buffer, 100, "%s:[%s]:%d", protocol, ip, port);
+
+    switch(family) {
+        case AF_INET:
+            snprintfz(buffer, 100, "%s:%s:%d", protocol, ip, port);
+            break;
+
+        case AF_INET6:
+        default:
+            snprintfz(buffer, 100, "%s:[%s]:%d", protocol, ip, port);
+            break;
+
+        case AF_UNIX:
+            snprintfz(buffer, 100, "%s:%s", protocol, ip);
+            break;
+    }
+
     sockets->fds_names[sockets->opened] = strdupz(buffer);
-    sockets->fds_types[sockets->opened] = socktype;
 
     sockets->opened++;
     return 0;
@@ -230,7 +291,7 @@ void listen_sockets_close(LISTEN_SOCKETS *sockets) {
     sockets->failed = 0;
 }
 
-static inline int bind_to_one(LISTEN_SOCKETS *sockets, const char *definition, int default_port, int listen_backlog) {
+static inline int bind_to_this(LISTEN_SOCKETS *sockets, const char *definition, int default_port, int listen_backlog) {
     int added = 0;
     struct addrinfo hints;
     struct addrinfo *result = NULL, *rp = NULL;
@@ -258,6 +319,22 @@ static inline int bind_to_one(LISTEN_SOCKETS *sockets, const char *definition, i
         socktype = SOCK_DGRAM;
         protocol_str = "udp";
     }
+    else if(strncmp(ip, "unix:", 5) == 0) {
+        char *path = ip + 5;
+        socktype = SOCK_STREAM;
+        protocol_str = "unix";
+
+        int fd = create_listen_socket_unix(path, listen_backlog);
+        if (fd == -1) {
+            error("LISTENER: Cannot create unix socket '%s'", path);
+            sockets->failed++;
+        }
+        else {
+            listen_sockets_add(sockets, fd, AF_UNIX, socktype, protocol_str, path, 0);
+            added++;
+        }
+        return added;
+    }
 
     char *e = ip;
     if(*e == '[') {
@@ -314,11 +391,13 @@ static inline int bind_to_one(LISTEN_SOCKETS *sockets, const char *definition, i
 
     for (rp = result; rp != NULL; rp = rp->ai_next) {
         int fd = -1;
+        int family = -1;
 
         char rip[INET_ADDRSTRLEN + INET6_ADDRSTRLEN] = "INVALID";
         int rport = default_port;
 
-        switch (rp->ai_addr->sa_family) {
+        family = rp->ai_addr->sa_family;
+        switch (family) {
             case AF_INET: {
                 struct sockaddr_in *sin = (struct sockaddr_in *) rp->ai_addr;
                 inet_ntop(AF_INET, &sin->sin_addr, rip, INET_ADDRSTRLEN);
@@ -338,7 +417,7 @@ static inline int bind_to_one(LISTEN_SOCKETS *sockets, const char *definition, i
             }
 
             default:
-                debug(D_LISTENER, "LISTENER: Unknown socket family %d", rp->ai_addr->sa_family);
+                debug(D_LISTENER, "LISTENER: Unknown socket family %d", family);
                 break;
         }
 
@@ -347,7 +426,7 @@ static inline int bind_to_one(LISTEN_SOCKETS *sockets, const char *definition, i
             sockets->failed++;
         }
         else {
-            listen_sockets_add(sockets, fd, socktype, protocol_str, rip, rport);
+            listen_sockets_add(sockets, fd, family, socktype, protocol_str, rip, rport);
             added++;
         }
     }
@@ -385,7 +464,7 @@ int listen_sockets_setup(LISTEN_SOCKETS *sockets) {
 
         char buf[e - s + 1];
         strncpyz(buf, s, e - s);
-        bind_to_one(sockets, buf, sockets->default_port, sockets->backlog);
+        bind_to_this(sockets, buf, sockets->default_port, sockets->backlog);
 
         s = e;
     }
@@ -403,7 +482,39 @@ int listen_sockets_setup(LISTEN_SOCKETS *sockets) {
 // --------------------------------------------------------------------------------------------------------------------
 // connect to another host/port
 
-// _connect_to()
+// connect_to_this_unix()
+// path        the path of the unix socket
+// timeout     the timeout for establishing a connection
+
+static inline int connect_to_unix(const char *path, struct timeval *timeout) {
+    int fd = socket(AF_UNIX, SOCK_STREAM, 0);
+    if(fd == -1) {
+        error("Failed to create UNIX socket() for '%s'", path);
+        return -1;
+    }
+
+    if(timeout) {
+        if(setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, (char *) timeout, sizeof(struct timeval)) < 0)
+            error("Failed to set timeout on UNIX socket '%s'", path);
+    }
+
+    struct sockaddr_un addr;
+    memset(&addr, 0, sizeof(addr));
+    addr.sun_family = AF_UNIX;
+    strncpy(addr.sun_path, path, sizeof(addr.sun_path)-1);
+
+    if (connect(fd, (struct sockaddr*)&addr, sizeof(addr)) == -1) {
+        error("Cannot connect to UNIX socket on path '%s'.", path);
+        close(fd);
+        return -1;
+    }
+
+    debug(D_CONNECT_TO, "Connected to UNIX socket on path '%s'.", path);
+
+    return fd;
+}
+
+// connect_to_this_ip46()
 // protocol    IPPROTO_TCP, IPPROTO_UDP
 // socktype    SOCK_STREAM, SOCK_DGRAM
 // host        the destination hostname or IP address (IPv4 or IPv6) to connect to
@@ -413,7 +524,7 @@ int listen_sockets_setup(LISTEN_SOCKETS *sockets) {
 // service     the service name or port to connect to
 // timeout     the timeout for establishing a connection
 
-static inline int _connect_to(int protocol, int socktype, const char *host, uint32_t scope_id, const char *service, struct timeval *timeout) {
+static inline int connect_to_this_ip46(int protocol, int socktype, const char *host, uint32_t scope_id, const char *service, struct timeval *timeout) {
     struct addrinfo hints;
     struct addrinfo *ai_head = NULL, *ai = NULL;
 
@@ -519,7 +630,7 @@ static inline int _connect_to(int protocol, int socktype, const char *host, uint
     return fd;
 }
 
-// connect_to()
+// connect_to_this()
 //
 // definition format:
 //
@@ -530,7 +641,7 @@ static inline int _connect_to(int protocol, int socktype, const char *host, uint
 // INTERFACE = for IPv6 only, the network interface to use
 // PORT      = port number or service name
 
-int connect_to(const char *definition, int default_port, struct timeval *timeout) {
+int connect_to_this(const char *definition, int default_port, struct timeval *timeout) {
     char buffer[strlen(definition) + 1];
     strcpy(buffer, definition);
 
@@ -551,6 +662,10 @@ int connect_to(const char *definition, int default_port, struct timeval *timeout
         protocol = IPPROTO_UDP;
         socktype = SOCK_DGRAM;
     }
+    else if(strncmp(host, "unix:", 5) == 0) {
+        char *path = host + 5;
+        return connect_to_unix(path, timeout);
+    }
 
     char *e = host;
     if(*e == '[') {
@@ -595,7 +710,7 @@ int connect_to(const char *definition, int default_port, struct timeval *timeout
         service = default_service;
 
 
-    return _connect_to(protocol, socktype, host, scope_id, service, timeout);
+    return connect_to_this_ip46(protocol, socktype, host, scope_id, service, timeout);
 }
 
 int connect_to_one_of(const char *destination, int default_port, struct timeval *timeout, size_t *reconnects_counter, char *connected_to, size_t connected_to_size) {
@@ -617,7 +732,7 @@ int connect_to_one_of(const char *destination, int default_port, struct timeval
         char buf[e - s + 1];
         strncpyz(buf, s, e - s);
         if(reconnects_counter) *reconnects_counter += 1;
-        sock = connect_to(buf, default_port, timeout);
+        sock = connect_to_this(buf, default_port, timeout);
         if(sock != -1) {
             if(connected_to && connected_to_size) {
                 strncpy(connected_to, buf, connected_to_size);
@@ -747,7 +862,7 @@ int accept_socket(int fd, int flags, char *client_ip, size_t ipsize, char *clien
     socklen_t addrlen = sizeof(sadr);
 
     int nfd = accept4(fd, (struct sockaddr *)&sadr, &addrlen, flags);
-    if (nfd >= 0) {
+    if (likely(nfd >= 0)) {
         if (getnameinfo((struct sockaddr *)&sadr, addrlen, client_ip, (socklen_t)ipsize, client_port, (socklen_t)portsize, NI_NUMERICHOST | NI_NUMERICSERV) != 0) {
             error("LISTENER: cannot getnameinfo() on received client connection.");
             strncpyz(client_ip, "UNKNOWN", ipsize - 1);
@@ -775,6 +890,10 @@ int accept_socket(int fd, int flags, char *client_ip, size_t ipsize, char *clien
                 break;
         }
     }
+#ifdef HAVE_ACCEPT4
+    else if(errno == ENOSYS)
+        error("netdata has been compiled with the assumption that the system has the accept4() call, but it is not here. Recompile netdata like this: ./configure --disable-accept4 ...");
+#endif
 
     return nfd;
 }