commit 53e4452f985cad0947cd8ebfa0a1c198b6a7da7d Author: George Kadianakis desnacked@riseup.net Date: Mon Jun 25 18:30:15 2012 +0300

Don't do DNS lookups when parsing corrupted managed proxy messages.

The functions parse_{s,c}method_line() were using tor_addr_port_lookup() which is capable of doing DNS lookups. DNS lookups should not be necessary when parsing {C,S}METHOD lines. --- changes/bug6226 | 3 +++ src/or/transports.c | 30 ++++++++++++++++++++++-------- 2 files changed, 25 insertions(+), 8 deletions(-)

diff --git a/changes/bug6226 b/changes/bug6226 new file mode 100644 index 0000000..7cbee10 --- /dev/null +++ b/changes/bug6226 @@ -0,0 +1,3 @@ + o Minor bugfixes: + - Don't do DNS lookups when parsing corrupted managed proxy + protocol messages. Fixes bug 6226; bugfix on 0.2.3.6-alpha. diff --git a/src/or/transports.c b/src/or/transports.c index e43ec6c..4ba2395 100644 --- a/src/or/transports.c +++ b/src/or/transports.c @@ -790,7 +790,8 @@ parse_smethod_line(const char *line, managed_proxy_t *mp) char *method_name=NULL;

char *addrport=NULL; - tor_addr_t addr; + tor_addr_t tor_addr; + char *address=NULL; uint16_t port = 0;

transport_t *transport=NULL; @@ -814,7 +815,7 @@ parse_smethod_line(const char *line, managed_proxy_t *mp) }

addrport = smartlist_get(items, 2); - if (tor_addr_port_lookup(addrport, &addr, &port)<0) { + if (tor_addr_port_split(LOG_PROTOCOL_WARN, addrport, &address, &port)<0) { log_warn(LD_CONFIG, "Error parsing transport " "address '%s'", addrport); goto err; @@ -826,7 +827,12 @@ parse_smethod_line(const char *line, managed_proxy_t *mp) goto err; }

- transport = transport_new(&addr, port, method_name, PROXY_NONE); + if (tor_addr_parse(&tor_addr, address) < 0) { + log_warn(LD_CONFIG, "Error parsing transport address '%s'", address); + goto err; + } + + transport = transport_new(&tor_addr, port, method_name, PROXY_NONE); if (!transport) goto err;

@@ -835,7 +841,7 @@ parse_smethod_line(const char *line, managed_proxy_t *mp) /* For now, notify the user so that he knows where the server transport is listening. */ log_info(LD_CONFIG, "Server transport %s at %s:%d.", - method_name, fmt_addr(&addr), (int)port); + method_name, address, (int)port);

r=0; goto done; @@ -846,6 +852,7 @@ parse_smethod_line(const char *line, managed_proxy_t *mp) done: SMARTLIST_FOREACH(items, char*, s, tor_free(s)); smartlist_free(items); + tor_free(address); return r; }

@@ -863,7 +870,8 @@ parse_cmethod_line(const char *line, managed_proxy_t *mp) int socks_ver=PROXY_NONE;

char *addrport=NULL; - tor_addr_t addr; + tor_addr_t tor_addr; + char *address=NULL; uint16_t port = 0;

transport_t *transport=NULL; @@ -899,7 +907,7 @@ parse_cmethod_line(const char *line, managed_proxy_t *mp) }

addrport = smartlist_get(items, 3); - if (tor_addr_port_lookup(addrport, &addr, &port)<0) { + if (tor_addr_port_split(LOG_PROTOCOL_WARN, addrport, &address, &port)<0) { log_warn(LD_CONFIG, "Error parsing transport " "address '%s'", addrport); goto err; @@ -911,7 +919,12 @@ parse_cmethod_line(const char *line, managed_proxy_t *mp) goto err; }

- transport = transport_new(&addr, port, method_name, socks_ver); + if (tor_addr_parse(&tor_addr, address) < 0) { + log_warn(LD_CONFIG, "Error parsing transport address '%s'", address); + goto err; + } + + transport = transport_new(&tor_addr, port, method_name, socks_ver); if (!transport) goto err;

@@ -919,7 +932,7 @@ parse_cmethod_line(const char *line, managed_proxy_t *mp)

log_info(LD_CONFIG, "Transport %s at %s:%d with SOCKS %d. " "Attached to managed proxy.", - method_name, fmt_addr(&addr), (int)port, socks_ver); + method_name, address, (int)port, socks_ver);

r=0; goto done; @@ -930,6 +943,7 @@ parse_cmethod_line(const char *line, managed_proxy_t *mp) done: SMARTLIST_FOREACH(items, char*, s, tor_free(s)); smartlist_free(items); + tor_free(address); return r; }