From 8cb412412127dafd88e6b6a5b39a6b897f174a7c Mon Sep 17 00:00:00 2001 From: Roger Dingledine Date: Tue, 3 Aug 2004 23:42:33 +0000 Subject: [PATCH] warn if we use an unsafe socks variant for now, warn every time. we should decide how often we want to warn; one problem here is that there are several scenarios where we use an unsafe socks variant safely, so the warning may be inaccurate. hm. svn:r2126 --- src/or/buffers.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/src/or/buffers.c b/src/or/buffers.c index 661b1e1587..222140e47a 100644 --- a/src/or/buffers.c +++ b/src/or/buffers.c @@ -409,6 +409,10 @@ int fetch_from_buf_http(buf_t *buf, return 1; } +/** If the user connects with socks4 or the wrong variant of socks5, + * then log one warning to let him know that it might be unwise. */ +static int have_warned_about_unsafe_socks = 0; + /** There is a (possibly incomplete) socks handshake on buf, of one * of the forms * - socks4: "socksheader username\\0" @@ -480,6 +484,10 @@ int fetch_from_buf_socks(buf_t *buf, socks_request_t *req) { log_fn(LOG_DEBUG,"socks5: ipv4 address type"); if(buf->datalen < 10) /* ip/port there? */ return 0; /* not yet */ + if(!have_warned_about_unsafe_socks) { + log_fn(LOG_WARN,"Your application is giving Tor only an IP address. Applications that do DNS resolves themselves may leak information. Consider using Socks4A (e.g. via privoxy or socat) instead."); +// have_warned_about_unsafe_socks = 1; // (for now, warn every time) + } destip = ntohl(*(uint32_t*)(buf->mem+4)); in.s_addr = htonl(destip); tmpbuf = inet_ntoa(in); @@ -556,6 +564,10 @@ int fetch_from_buf_socks(buf_t *buf, socks_request_t *req) { } startaddr = next+1; + if(socks4_prot != socks4a && !have_warned_about_unsafe_socks) { + log_fn(LOG_WARN,"Your application is giving Tor only an IP address. Applications that do DNS resolves themselves may leak information. Consider using Socks4A (e.g. via privoxy or socat) instead."); +// have_warned_about_unsafe_socks = 1; // (for now, warn every time) + } if(socks4_prot == socks4a) { next = memchr(startaddr, 0, buf->mem+buf->datalen-startaddr); if(!next) {