chiark / gitweb /
fds: Provide cloexec() and use it in udp.c and tun.c
[secnet.git] / udp.c
diff --git a/udp.c b/udp.c
index 483ed37..bb82026 100644 (file)
--- a/udp.c
+++ b/udp.c
@@ -19,6 +19,7 @@
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include "util.h"
+#include "magic.h"
 #include "unaligned.h"
 #include "ipaddr.h"
 #include "magic.h"
@@ -102,8 +103,10 @@ static void udp_afterpoll(void *state, struct pollfd *fds, int nfds)
            fromlen=sizeof(from);
            BUF_ASSERT_FREE(st->rbuf);
            BUF_ALLOC(st->rbuf,"udp_afterpoll");
-           rv=recvfrom(st->fd, st->rbuf->start, st->rbuf->len, 0,
-                       (struct sockaddr *)&from, &fromlen);
+           buffer_init(st->rbuf,calculate_max_start_pad());
+           rv=recvfrom(st->fd, st->rbuf->start,
+                       buf_remaining_space(st->rbuf),
+                       0, (struct sockaddr *)&from, &fromlen);
            if (rv>0) {
                st->rbuf->size=rv;
                if (st->use_proxy) {
@@ -193,12 +196,13 @@ static bool_t udp_sendmsg(void *commst, struct buffer_if *buf,
     uint8_t *sa;
 
     if (st->use_proxy) {
-       sa=buf->start-8;
+       sa=buf_prepend(buf,8);
        memcpy(sa,&dest->sin.sin_addr,4);
        memset(sa+4,0,4);
        memcpy(sa+6,&dest->sin.sin_port,2);
        sendto(st->fd,sa,buf->size+8,0,(struct sockaddr *)&st->proxy,
               sizeof(st->proxy));
+       buf_unprepend(buf,8);
     } else {
        sendto(st->fd, buf->start, buf->size, 0,
               (struct sockaddr *)&dest->sin, sizeof(dest->sin));
@@ -220,10 +224,7 @@ static void udp_phase_hook(void *sst, uint32_t new_phase)
        fatal_perror("udp (%s:%d): fcntl(set O_NONBLOCK)",
                     st->loc.file,st->loc.line);
     }
-    if (fcntl(st->fd, F_SETFD, FD_CLOEXEC)==-1) {
-       fatal_perror("udp (%s:%d): fcntl(set FD_CLOEXEC)",
-                    st->loc.file,st->loc.line);
-    }
+    setcloexec(st->fd);
 
     FILLZERO(addr);
     addr.sin_family=AF_INET;
@@ -288,8 +289,6 @@ static list_t *udp_apply(closure_t *self, struct cloc loc, dict_t *context,
     st->cl.apply=NULL;
     st->cl.interface=&st->ops;
     st->ops.st=st;
-    st->ops.min_start_pad=0;
-    st->ops.min_end_pad=0;
     st->ops.request_notify=request_notify;
     st->ops.release_notify=release_notify;
     st->ops.sendmsg=udp_sendmsg;
@@ -324,9 +323,10 @@ static list_t *udp_apply(closure_t *self, struct cloc loc, dict_t *context,
            cfgfatal(st->loc,"udp","proxy must supply ""addr"",port\n");
        }
        st->proxy.sin_port=htons(i->data.number);
-       st->ops.min_start_pad=8;
     }
 
+    update_max_start_pad(&comm_max_start_pad, st->use_proxy ? 8 : 0);
+
     add_hook(PHASE_GETRESOURCES,udp_phase_hook,st);
 
     return new_closure(&st->cl);