chiark / gitweb /
Static buffers: ipaddr_getbuf: Rename some variables
[secnet.git] / udp.c
diff --git a/udp.c b/udp.c
index 8947058..dde73ef 100644 (file)
--- a/udp.c
+++ b/udp.c
@@ -30,6 +30,7 @@ static comm_sendmsg_fn udp_sendmsg;
 struct udp {
     struct udpcommon uc;
     struct udpsocks socks;
+    bool_t addr_configured;
 };
 
 /*
@@ -54,7 +55,7 @@ static const char *udp_addr_to_string(void *commst, const struct comm_addr *ca)
     assert(ix>=0 && ix<socks->n_socks);
     snprintf(sbuf, sizeof(sbuf), "udp:%s%s-%s",
             iaddr_to_string(&socks->socks[ix].addr),
-            ca->ix<0 ? "&" : "",
+            ca->ix<0 && socks->n_socks>1 ? "&" : "",
             iaddr_to_string(&ca->ia));
     return sbuf;
 }
@@ -72,6 +73,37 @@ static int udp_socks_beforepoll(void *state, struct pollfd *fds, int *nfds_io,
     return 0;
 }
 
+const char *af_name(int af)
+{
+    switch (af) {
+    case AF_INET6: return "IPv6";
+    case AF_INET:  return "IPv4";
+    case 0:        return "(any)";
+    default: abort();
+    }
+}
+
+void udp_sock_experienced(struct log_if *lg, struct udpcommon *uc,
+                         struct udpsocks *socks, struct udpsock *us,
+                         const union iaddr *dest, int af,
+                         int r, int errnoval)
+{
+    bool_t success=r>=0;
+    if (us->experienced[!!dest][af][success]++)
+       return;
+    lg_perror(lg, uc->cc.cl.description, &uc->cc.loc,
+             success ? M_INFO : M_WARNING,
+             success ? 0 : errnoval,
+             "%s %s experiencing some %s %s%s%s%s%s%s",
+             socks->desc,iaddr_to_string(&us->addr),
+             success?"success":"trouble",
+             dest?"transmitting":"receiving",
+             af?" ":"", af?af_name(af):"",
+             dest?" (to ":"",
+             dest?iaddr_to_string(dest):"",
+             dest?")":"");
+}
+
 static void udp_socks_afterpoll(void *state, struct pollfd *fds, int nfds)
 {
     struct udpsocks *socks=state;
@@ -85,10 +117,11 @@ static void udp_socks_afterpoll(void *state, struct pollfd *fds, int nfds)
     struct commcommon *cc=&uc->cc;
 
     for (i=0; i<socks->n_socks; i++) {
+       struct udpsock *us=&socks->socks[i];
        if (i>=nfds) continue;
        if (!(fds[i].revents & POLLIN)) continue;
-       assert(fds[i].fd == socks->socks[i].fd);
-       int fd=socks->socks[i].fd;
+       assert(fds[i].fd == us->fd);
+       int fd=us->fd;
        do {
            fromlen=sizeof(from);
            BUF_ASSERT_FREE(cc->rbuf);
@@ -103,7 +136,7 @@ static void udp_socks_afterpoll(void *state, struct pollfd *fds, int nfds)
                    /* Check that the packet came from our poxy server;
                       we shouldn't be contacted directly by anybody else
                       (since they can trivially forge source addresses) */
-                   if (!iaddr_equal(&from,&uc->proxy)) {
+                   if (!iaddr_equal(&from,&uc->proxy,False)) {
                        Message(M_INFO,"udp: received packet that's not "
                                "from the proxy\n");
                        BUF_FREE(cc->rbuf);
@@ -120,7 +153,10 @@ static void udp_socks_afterpoll(void *state, struct pollfd *fds, int nfds)
                ca.ia=from;
                ca.ix=i;
                done=comm_notify(&cc->notify, cc->rbuf, &ca);
-               if (!done) {
+               if (done) {
+                   udp_sock_experienced(0,uc,socks,us,0,
+                                        from.sa.sa_family,0,0);
+               } else {
                    uint32_t msgtype;
                    if (cc->rbuf->size>12 /* prevents traffic amplification */
                        && ((msgtype=get_uint32(cc->rbuf->start+8))
@@ -134,7 +170,9 @@ static void udp_socks_afterpoll(void *state, struct pollfd *fds, int nfds)
                    BUF_FREE(cc->rbuf);
                }
                BUF_ASSERT_FREE(cc->rbuf);
-           } else {
+           } else { /* rv<=0 */
+               if (errno!=EINTR && !iswouldblock(errno))
+                   udp_sock_experienced(0,uc,socks,us, 0,0, rv,errno);
                BUF_FREE(cc->rbuf);
            }
        } while (rv>=0);
@@ -150,6 +188,7 @@ static bool_t udp_sendmsg(void *commst, struct buffer_if *buf,
     uint8_t *sa;
 
     if (uc->use_proxy) {
+       struct udpsock *us=&socks->socks[0];
        sa=buf_prepend(buf,8);
        if (dest->ia.sa.sa_family != AF_INET) {
            Message(M_INFO,
@@ -160,18 +199,22 @@ static bool_t udp_sendmsg(void *commst, struct buffer_if *buf,
        memcpy(sa,&dest->ia.sin.sin_addr,4);
        memset(sa+4,0,4);
        memcpy(sa+6,&dest->ia.sin.sin_port,2);
-       sendto(socks->socks[0].fd,sa,buf->size+8,0,&uc->proxy.sa,
+       int r=sendto(us->fd,sa,buf->size+8,0,&uc->proxy.sa,
               iaddr_socklen(&uc->proxy));
+       udp_sock_experienced(0,uc,socks,us, &dest->ia,0, r,errno);
        buf_unprepend(buf,8);
     } else {
        int i,r;
        bool_t allunsupported=True;
+       int af=dest->ia.sa.sa_family;
        for (i=0; i<socks->n_socks; i++) {
-           if (dest->ia.sa.sa_family != socks->socks[i].addr.sa.sa_family)
+           struct udpsock *us=&socks->socks[i];
+           if (us->addr.sa.sa_family != af)
                /* no point even trying */
                continue;
-           r=sendto(socks->socks[i].fd, buf->start, buf->size, 0,
+           r=sendto(us->fd, buf->start, buf->size, 0,
                     &dest->ia.sa, iaddr_socklen(&dest->ia));
+           udp_sock_experienced(0,uc,socks,us, &dest->ia,af, r,errno);
            if (r>=0) return True;
            if (!(errno==EAFNOSUPPORT || errno==ENETUNREACH))
                /* who knows what that error means? */
@@ -191,6 +234,34 @@ void udp_destroy_socket(struct udpcommon *uc, struct udpsock *us)
     }
 }
 
+#define FAIL_LG 0, cc->cl.description, &cc->loc, failmsgclass
+#define FAIL(...) do{                                          \
+        lg_perror(FAIL_LG,errno,__VA_ARGS__);  \
+       goto failed;                                            \
+    }while(0)
+
+static bool_t record_socket_gotaddr(struct udpcommon *uc, struct udpsock *us,
+                                   int failmsgclass)
+{
+    struct commcommon *cc=&uc->cc;
+    socklen_t salen=sizeof(us->addr);
+    int r=getsockname(us->fd,&us->addr.sa,&salen);
+    if (r) FAIL("getsockname()");
+    if (salen>sizeof(us->addr)) { errno=0; FAIL("getsockname() length"); }
+    return True;
+
+ failed:
+    return False;
+}
+
+bool_t udp_import_socket(struct udpcommon *uc, struct udpsock *us,
+                        int failmsgclass, int fd)
+{
+    FILLZERO(us->experienced);
+    us->fd=fd;
+    return record_socket_gotaddr(uc,us,failmsgclass);
+}
+
 bool_t udp_make_socket(struct udpcommon *uc, struct udpsock *us,
                       int failmsgclass)
 {
@@ -198,16 +269,10 @@ bool_t udp_make_socket(struct udpcommon *uc, struct udpsock *us,
     struct commcommon *cc=&uc->cc;
     us->fd=-1;
 
-#define FAIL_LG 0, cc->cl.description, &cc->loc, failmsgclass
-#define FAIL(...) do{                                          \
-        lg_perror(FAIL_LG,errno,__VA_ARGS__);  \
-       goto failed;                                            \
-    }while(0)
-
+    FILLZERO(us->experienced);
     us->fd=socket(addr->sa.sa_family, SOCK_DGRAM, IPPROTO_UDP);
     if (us->fd<0) FAIL("socket");
-    if (fcntl(us->fd, F_SETFL, fcntl(us->fd, F_GETFL)|O_NONBLOCK)==-1)
-       FAIL("fcntl(set O_NONBLOCK)");
+    setnonblock(us->fd);
     setcloexec(us->fd);
 #ifdef CONFIG_IPV6
     if (addr->sa.sa_family==AF_INET6) {
@@ -222,6 +287,9 @@ bool_t udp_make_socket(struct udpcommon *uc, struct udpsock *us,
     if (uc->authbind) {
        pid_t c;
        int status;
+       char desc[200];
+       snprintf(desc,sizeof(desc),"authbind for %s: %s",
+                iaddr_to_string(addr), uc->authbind);
 
        /* XXX this fork() and waitpid() business needs to be hidden
           in some system-specific library functions. */
@@ -271,10 +339,10 @@ bool_t udp_make_socket(struct udpcommon *uc, struct udpsock *us,
            if (WIFEXITED(status) && WEXITSTATUS(status)<127) {
                int es=WEXITSTATUS(status);
                lg_perror(FAIL_LG,es,
-                         "authbind exited with error exit status %d;"
-                         " indicates error",es);
+                         "%s exited with error exit status %d;"
+                         " indicates error",desc,es);
            } else {
-               lg_exitstatus(FAIL_LG,status,"authbind");
+               lg_exitstatus(FAIL_LG,status,desc);
            }
            goto failed;
        }
@@ -282,18 +350,24 @@ bool_t udp_make_socket(struct udpcommon *uc, struct udpsock *us,
        if (bind(us->fd, &addr->sa, iaddr_socklen(addr))!=0)
            FAIL("bind (%s)",iaddr_to_string(addr));
     }
+
+    bool_t ok=record_socket_gotaddr(uc,us,failmsgclass);
+    if (!ok) goto failed;
+
     return True;
 
 failed:
     udp_destroy_socket(uc,us);
     return False;
+}
 
 #undef FAIL
-}
 
-void udp_socks_register(struct udpcommon *uc, struct udpsocks *socks)
+void udp_socks_register(struct udpcommon *uc, struct udpsocks *socks,
+                       const char *desc)
 {
     socks->uc=uc;
+    socks->desc=desc;
     socks->interest=
        register_for_poll(socks,udp_socks_beforepoll,udp_socks_afterpoll,"udp");
 }
@@ -304,16 +378,37 @@ void udp_socks_deregister(struct udpcommon *uc, struct udpsocks *socks)
     deregister_for_poll(socks->interest);
 }
 
+void udp_socks_childpersist(struct udpcommon *uc, struct udpsocks *socks)
+{
+    int i;
+    for (i=0; i<socks->n_socks; i++)
+       udp_destroy_socket(uc,&socks->socks[i]);
+}
+
+static void udp_childpersist_hook(void *sst, uint32_t new_phase)
+{
+    struct udp *st=sst;
+    udp_socks_childpersist(&st->uc,&st->socks);
+}
+
 static void udp_phase_hook(void *sst, uint32_t new_phase)
 {
     struct udp *st=sst;
     struct udpsocks *socks=&st->socks;
     struct udpcommon *uc=&st->uc;
     int i;
-    for (i=0; i<socks->n_socks; i++)
-       udp_make_socket(uc,&socks->socks[i],M_FATAL);
+    bool_t anydone=0;
+
+    for (i=0; i<socks->n_socks; i++) {
+       bool_t required=st->addr_configured
+           || (!anydone && i==socks->n_socks-1);
+       anydone += udp_make_socket(uc,&socks->socks[i],
+                                  required ? M_FATAL : M_WARNING);
+    }
+
+    udp_socks_register(uc,socks, uc->use_proxy ? "proxy" : "socket");
 
-    udp_socks_register(uc,socks);
+    add_hook(PHASE_CHILDPERSIST,udp_childpersist_hook,st);
 }
 
 static list_t *udp_apply(closure_t *self, struct cloc loc, dict_t *context,
@@ -345,14 +440,16 @@ static list_t *udp_apply(closure_t *self, struct cloc loc, dict_t *context,
     };
 
     caddrl=dict_lookup(d,"address");
-    socks->n_socks=caddrl ? list_length(caddrl) : (int)ARRAY_SIZE(defaultaddrs);
+    st->addr_configured=!!caddrl;
+    socks->n_socks=st->addr_configured ? list_length(caddrl)
+       : (int)ARRAY_SIZE(defaultaddrs);
     if (socks->n_socks<=0 || socks->n_socks>UDP_MAX_SOCKETS)
        cfgfatal(cc->loc,"udp","`address' must be 1..%d addresses",
                 UDP_MAX_SOCKETS);
 
     for (i=0; i<socks->n_socks; i++) {
        struct udpsock *us=&socks->socks[i];
-       if (!list_length(caddrl)) {
+       if (!st->addr_configured) {
            us->addr=defaultaddrs[i];
        } else {
            string_item_to_iaddr(list_elem(caddrl,i),uc->port,&us->addr,"udp");