3 files changed, 108 insertions, 2 deletions

diff --git a/ChangeLog b/ChangeLog
index 93f6b8a20..20aa4bd5c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -4,6 +4,12 @@
      packet_bacup_state() and packet_restore_state() will be used to
      temporarily save the current state ren resuming a suspended connection.
      ok markus@
+   - andreas@cvs.openbsd.org 2009/06/27 09:32:43
+     [roaming_common.c roaming.h]
+     It may be necessary to retransmit some data when resuming, so add it
+     to a buffer when roaming is enabled.
+     Most of this code was written by Martin Forssen, maf at appgate dot com.
+     ok markus@
 
 20090622
  - (dtucker) OpenBSD CVS Sync
diff --git a/roaming.h b/roaming.h
index e99465502..e517161f6 100644
--- a/roaming.h
+++ b/roaming.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: roaming.h,v 1.3 2009/06/21 09:04:03 dtucker Exp $ */
+/* $OpenBSD: roaming.h,v 1.4 2009/06/27 09:32:43 andreas Exp $ */
 /*
  * Copyright (c) 2004-2009 AppGate Network Security AB
  *
@@ -18,15 +18,21 @@
 #ifndef ROAMING_H
 #define ROAMING_H
 
+#define DEFAULT_ROAMBUF 65536
+
 extern int resume_in_progress;
 
+int     get_snd_buf_size(void);
+int     get_recv_buf_size(void);
 void    add_recv_bytes(u_int64_t);
+void    set_out_buffer_size(size_t);
 ssize_t roaming_write(int, const void *, size_t, int *);
 ssize_t roaming_read(int, void *, size_t, int *);
 size_t  roaming_atomicio(ssize_t (*)(int, void *, size_t), int, void *, size_t);
 u_int64_t       get_recv_bytes(void);
 u_int64_t       get_sent_bytes(void);
 void    roam_set_bytes(u_int64_t, u_int64_t);
+void    resend_bytes(int, u_int64_t *);
 int     resume_kex(void);
 
 #endif /* ROAMING */
diff --git a/roaming_common.c b/roaming_common.c
index 14dd5808f..73db09d79 100644
--- a/roaming_common.c
+++ b/roaming_common.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: roaming_common.c,v 1.4 2009/06/21 09:04:03 dtucker Exp $ */
+/* $OpenBSD: roaming_common.c,v 1.5 2009/06/27 09:32:43 andreas Exp $ */
 /*
  * Copyright (c) 2004-2009 AppGate Network Security AB
  *
@@ -26,6 +26,7 @@
 #include <inttypes.h>
 #endif
 #include <stdarg.h>
+#include <string.h>
 #include <unistd.h>
 
 #include "atomicio.h"
@@ -36,11 +37,56 @@
 #include "buffer.h"
 #include "roaming.h"
 
+static size_t out_buf_size = 0;
+static char *out_buf = NULL;
+static size_t out_start;
+static size_t out_last;
+
 static u_int64_t write_bytes = 0;
 static u_int64_t read_bytes = 0;
 
+int roaming_enabled = 0;
 int resume_in_progress = 0;
 
+int
+get_snd_buf_size()
+{
+        int fd = packet_get_connection_out();
+        int optval, optvallen;
+
+        optvallen = sizeof(optval);
+        if (getsockopt(fd, SOL_SOCKET, SO_SNDBUF, &optval, &optvallen) != 0)
+                optval = DEFAULT_ROAMBUF;
+        return optval;
+}
+
+int
+get_recv_buf_size()
+{
+        int fd = packet_get_connection_in();
+        int optval, optvallen;
+
+        optvallen = sizeof(optval);
+        if (getsockopt(fd, SOL_SOCKET, SO_RCVBUF, &optval, &optvallen) != 0)
+                optval = DEFAULT_ROAMBUF;
+        return optval;
+}
+
+void
+set_out_buffer_size(size_t size)
+{
+        /*
+         * The buffer size can only be set once and the buffer will live
+         * as long as the session lives.
+         */
+        if (out_buf == NULL) {
+                out_buf_size = size;
+                out_buf = xmalloc(size);
+                out_start = 0;
+                out_last = 0;
+        }
+}
+
 u_int64_t
 get_recv_bytes(void)
 {
@@ -66,6 +112,28 @@ roam_set_bytes(u_int64_t sent, u_int64_t recvd)
         write_bytes = sent;
 }
 
+static void
+buf_append(const char *buf, size_t count)
+{
+        if (count > out_buf_size) {
+                buf += count - out_buf_size;
+                count = out_buf_size;
+        }
+        if (count < out_buf_size - out_last) {
+                memcpy(out_buf + out_last, buf, count);
+                if (out_start > out_last)
+                        out_start += count;
+                out_last += count;
+        } else {
+                /* data will wrap */
+                size_t chunk = out_buf_size - out_last;
+                memcpy(out_buf + out_last, buf, chunk);
+                memcpy(out_buf, buf + chunk, count - chunk);
+                out_last = count - chunk;
+                out_start = out_last + 1;
+        }
+}
+
 ssize_t
 roaming_write(int fd, const void *buf, size_t count, int *cont)
 {
@@ -74,6 +142,8 @@ roaming_write(int fd, const void *buf, size_t count, int *cont)
         ret = write(fd, buf, count);
         if (ret > 0 && !resume_in_progress) {
                 write_bytes += ret;
+                if (out_buf_size > 0)
+                        buf_append(buf, ret);
         }
         debug3("Wrote %ld bytes for a total of %llu", (long)ret,
             (unsigned long long)write_bytes);
@@ -105,3 +175,27 @@ roaming_atomicio(ssize_t(*f)(int, void*, size_t), int fd, void *buf,
         }
         return ret;
 }
+
+void
+resend_bytes(int fd, u_int64_t *offset)
+{
+        size_t available, needed;
+
+        if (out_start < out_last)
+                available = out_last - out_start;
+        else
+                available = out_buf_size;
+        needed = write_bytes - *offset;
+        debug3("resend_bytes: resend %lu bytes from %llu",
+            (unsigned long)needed, (unsigned long long)*offset);
+        if (needed > available)
+                fatal("Needed to resend more data than in the cache");
+        if (out_last < needed) {
+                int chunkend = needed - out_last;
+                atomicio(vwrite, fd, out_buf + out_buf_size - chunkend,
+                    chunkend);
+                atomicio(vwrite, fd, out_buf, out_last);
+        } else {
+                atomicio(vwrite, fd, out_buf + (out_last - needed), needed);
+        }
+}