From 7d8e17c4434c5c86f6e10dba1495c116840b9520 Mon Sep 17 00:00:00 2001 From: david-sarah Date: Fri, 10 Sep 2010 12:32:34 -0700 Subject: [PATCH] docs/frontends/FTP-and-SFTP.txt: warn users about connecting to the FTP and SFTP servers remotely. Fixes #1192 --- docs/frontends/FTP-and-SFTP.txt | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) diff --git a/docs/frontends/FTP-and-SFTP.txt b/docs/frontends/FTP-and-SFTP.txt index 41ee8fa5..883e660e 100644 --- a/docs/frontends/FTP-and-SFTP.txt +++ b/docs/frontends/FTP-and-SFTP.txt @@ -95,6 +95,11 @@ that server in an "accounts.url" directive: You can provide both accounts.file and accounts.url, although it probably isn't very useful except for testing. +FTP provides no security, and so your password or caps could be eavesdropped +if you connect to the FTP server remotely. The examples above include +":interface=127.0.0.1" in the "port" option, which causes the server to only +accept connections from localhost. + == Configuring SFTP Access == @@ -105,6 +110,17 @@ program talks to a given server, it will store the host key it receives, and will complain if a subsequent connection uses a different key. This reduces the opportunity for man-in-the-middle attacks to just the first connection. +Exercise caution when connecting to the SFTP server remotely. The AES +implementation used by the SFTP code does not have defenses against timing +attacks. The code for encrypting the SFTP connection was not written by the +Tahoe-LAFS team, and we have not reviewed it as carefully as we have reviewed +the code for encrypting files and directories in Tahoe-LAFS itself. If you +can connect to the SFTP server (which is provided by the Tahoe-LAFS gateway) +only from a client on the same host, then you would be safe from any problem +with the SFTP connection security. The examples given below enforce this +policy by including ":interface=127.0.0.1" in the "port" option, which +causes the server to only accept connections from localhost. + You will use directives in the tahoe.cfg file to tell the SFTP code where to find these keys. To create one, use the ssh-keygen tool (which comes with the standard openssh client distribution): @@ -119,7 +135,7 @@ lines to the BASEDIR/tahoe.cfg file: [sftpd] enabled = true - port = tcp:8022:interface=127.0.0.1 + port = tcp:8022:interface=127.0.0.1 host_pubkey_file = private/ssh_host_rsa_key.pub host_privkey_file = private/ssh_host_rsa_key accounts.file = private/ftp.accounts -- 2.45.2