1 files changed, 35 insertions, 0 deletions
diff --git a/sysdep/linux/sysio.h b/sysdep/linux/sysio.h
index 6e541109..2fa5f0a9 100644
--- a/sysdep/linux/sysio.h
+++ b/sysdep/linux/sysio.h
@@ -160,3 +160,38 @@ struct tcp_md5sig {
 };
 
 #endif
+
+static int
+sk_set_md5_auth_int(sock *s, sockaddr *sa, char *passwd)
+{
+  struct tcp_md5sig md5;
+
+  memset(&md5, 0, sizeof(md5));
+  memcpy(&md5.tcpm_addr, (struct sockaddr *) sa, sizeof(*sa));
+
+  if (passwd)
+    {
+      int len = strlen(passwd);
+
+      if (len > TCP_MD5SIG_MAXKEYLEN)
+	{
+	  log(L_ERR "MD5 password too long");
+	  return -1;
+	}
+
+      md5.tcpm_keylen = len;
+      memcpy(&md5.tcpm_key, passwd, len);
+    }
+
+  int rv = setsockopt(s->fd, IPPROTO_TCP, TCP_MD5SIG, &md5, sizeof(md5));
+
+  if (rv < 0) 
+    {
+      if (errno == ENOPROTOOPT)
+	log(L_ERR "Kernel does not support TCP MD5 signatures");
+      else
+	log(L_ERR "sk_set_md5_auth_int: setsockopt: %m");
+    }
+
+  return rv;
+}