Remove size limit for files inlined in config

As described in trac #484, the current inline file size limit of 10000
bytes is becoming an issue for some users.  Since RSA keys and signature
sizes are increasing, we need to adjust our limits.  As #484 reports,
10000 can be too small for PKCS#12 files with 4K RSA keys.  Instead of
postponing this issue by increasing the static limit, dynamically increase
the buffer size while reading. This keeps the memory usage limited but does
allow for larger inlined files.

Signed-off-by: Steffan Karger <steffan@karger.me>
Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: <1430122342-11742-1-git-send-email-steffan@karger.me>
URL: http://article.gmane.org/gmane.network.openvpn.devel/9607
Signed-off-by: Gert Doering <gert@greenie.muc.de>

1 files changed, 10 insertions, 1 deletions

diff --git a/src/openvpn/options.c b/src/openvpn/options.c
index 4f27336..6d5e58e 100644
--- a/src/openvpn/options.c
+++ b/src/openvpn/options.c
@@ -3698,12 +3698,21 @@ static char *
 read_inline_file (struct in_src *is, const char *close_tag, struct gc_arena *gc)
 {
   char line[OPTION_LINE_SIZE];
-  struct buffer buf = alloc_buf (10000);
+  struct buffer buf = alloc_buf (8*OPTION_LINE_SIZE);
   char *ret;
   while (in_src_get (is, line, sizeof (line)))
     {
       if (!strncmp (line, close_tag, strlen (close_tag)))
 	break;
+      if (!buf_safe (&buf, strlen(line)))
+	{
+	  /* Increase buffer size */
+	  struct buffer buf2 = alloc_buf (buf.capacity * 2);
+	  ASSERT (buf_copy (&buf2, &buf));
+	  buf_clear (&buf);
+	  free_buf (&buf);
+	  buf = buf2;
+	}
       buf_printf (&buf, "%s", line);
     }
   ret = string_alloc (BSTR (&buf), gc);