diff mbox series

[Openvpn-devel,v2] Implement ovpn version detection

Message ID 20250515150038.30097-1-gert@greenie.muc.de
State Accepted
Headers
Series [Openvpn-devel,v2] Implement ovpn version detection |

Commit Message

Gert Doering May 15, 2025, 3 p.m. UTC 
  From: Ralf Lici <ralf@mandelbit.com>

Add detection of the ovpn kernel module type: if a backported
(out-of-tree) version is loaded, the MODULE_VERSION string is read from
sysfs; otherwise, for the in-tree module, the function reports the
kernel release and version.

Change-Id: I7fc033a7ffee73045316763356a95d75ef23f5ad
Signed-off-by: Ralf Lici <ralf@mandelbit.com>
Acked-by: Gert Doering <gert@greenie.muc.de>
---

This change was reviewed on Gerrit and approved by at least one
developer. I request to merge it to master.

Gerrit URL: https://gerrit.openvpn.net/c/openvpn/+/1022
This mail reflects revision 2 of this Change.

Acked-by according to Gerrit (reflected above):
Gert Doering <gert@greenie.muc.de>

Comments

Gert Doering May 15, 2025, 3:12 p.m. UTC | #1 
Tested various complications - no module available, module without
"local" version number available (= built-in, in the future), and
new "backport" module.  Does what it says on the lid.

Your patch has been applied to the master branch.

commit f6c95ac2ffa69a1caaf2785859c48295a3bea199
Author: Ralf Lici
Date:   Thu May 15 17:00:31 2025 +0200

     Implement ovpn version detection

     Signed-off-by: Ralf Lici <ralf@mandelbit.com>
     Acked-by: Gert Doering <gert@greenie.muc.de>
     Message-Id: <20250515150038.30097-1-gert@greenie.muc.de>
     URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg31652.html
     Signed-off-by: Gert Doering <gert@greenie.muc.de>


--
kind regards,

Gert Doering
diff mbox series

Patch

diff --git a/src/openvpn/dco_linux.c b/src/openvpn/dco_linux.c
index c950e3d..a5f9e06 100644
--- a/src/openvpn/dco_linux.c
+++ b/src/openvpn/dco_linux.c
@@ -1117,10 +1117,77 @@ 
     return true;
 }
 
+/**
+ * There's no version indicator in the ovpn in-tree module, so we return a
+ * string containing info about the kernel version and release.
+ */
+static const char *
+dco_version_string_in_tree(struct gc_arena *gc)
+{
+    struct buffer buf = alloc_buf_gc(256, gc);
+    struct utsname system;
+
+    if (uname(&system))
+    {
+        return "ERR";
+    }
+
+    buf_puts(&buf, system.release);
+    buf_puts(&buf, " ");
+    buf_puts(&buf, system.version);
+    return BSTR(&buf);
+}
+
+/**
+ * When the module is loaded, the backports version of ovpn has a version file
+ * in sysfs. Read it and return the string.
+ *
+ * The caller is responsible for closing the file pointer.
+ */
+static const char *
+dco_version_string_backports(FILE *fp, struct gc_arena *gc)
+{
+    char *str = gc_malloc(PATH_MAX, false, gc);
+
+    if (!fgets(str, PATH_MAX, fp))
+    {
+        return "ERR";
+    }
+
+    /* remove potential newline at the end of the string */
+    char *nl = strchr(str, '\n');
+    if (nl)
+    {
+        *nl = '\0';
+    }
+
+    return str;
+}
+
 const char *
 dco_version_string(struct gc_arena *gc)
 {
-    return "Unknown";
+    const char *version;
+    struct stat sb;
+    FILE *fp;
+
+    if (stat("/sys/module/ovpn", &sb) != 0 || !S_ISDIR(sb.st_mode))
+    {
+        return "N/A";
+    }
+
+    /* now that we know for sure that the module is loaded, if there's no
+     * version file it means we're dealing with the in-tree version, otherwise
+     * it's backports */
+    fp = fopen("/sys/module/ovpn/version", "r");
+    if (!fp)
+    {
+        return dco_version_string_in_tree(gc);
+    }
+    version = dco_version_string_backports(fp, gc);
+
+    fclose(fp);
+    return version;
 }
 
 void