void backend_socket_log(void *frontend, int type, SockAddr addr, int port,
const char *error_msg, int error_code, Conf *conf,
int session_started)
{
char addrbuf[256], *msg;
switch (type) {
case 0:
sk_getaddr(addr, addrbuf, lenof(addrbuf));
if (sk_addr_needs_port(addr)) {
msg = dupprintf("Connecting to %s port %d", addrbuf, port);
} else {
msg = dupprintf("Connecting to %s", addrbuf);
}
break;
case 1:
sk_getaddr(addr, addrbuf, lenof(addrbuf));
msg = dupprintf("Failed to connect to %s: %s", addrbuf, error_msg);
break;
case 2:
/* Proxy-related log messages have their own identifying
* prefix already, put on by our caller. */
{
int len, log_to_term;
/* Suffix \r\n temporarily, so we can log to the terminal. */
msg = dupprintf("%s\r\n", error_msg);
len = (int)strlen(msg);
assert(len >= 2);
log_to_term = conf_get_int(conf, CONF_proxy_log_to_term);
if (log_to_term == AUTO)
log_to_term = session_started ? FORCE_OFF : FORCE_ON;
if (log_to_term == FORCE_ON)
from_backend(frontend, TRUE, msg, len);
msg[len-2] = '\0'; /* remove the \r\n again */
}
break;
default:
msg = NULL; /* shouldn't happen, but placate optimiser */
break;
}
if (msg) {
logevent(frontend, msg);
sfree(msg);
}
}
int proxy_http_negotiate (ProxySocket *p, int change)
{
if (p->state == PROXY_STATE_NEW) {
/* we are just beginning the proxy negotiate process,
* so we'll send off the initial bits of the request.
* for this proxy method, it's just a simple HTTP
* request
*/
char *buf, dest[512];
char *username, *password;
sk_getaddr(p->remote_addr, dest, lenof(dest));
buf = dupprintf("CONNECT %s:%i HTTP/1.1\r\nHost: %s:%i\r\n",
dest, p->remote_port, dest, p->remote_port);
sk_write(p->sub_socket, buf, strlen(buf));
sfree(buf);
username = conf_get_str(p->conf, CONF_proxy_username);
password = conf_get_str(p->conf, CONF_proxy_password);
if (username[0] || password[0]) {
char *buf, *buf2;
int i, j, len;
buf = dupprintf("%s:%s", username, password);
len = strlen(buf);
buf2 = snewn(len * 4 / 3 + 100, char);
sprintf(buf2, "Proxy-Authorization: Basic ");
for (i = 0, j = strlen(buf2); i < len; i += 3, j += 4)
base64_encode_atom((unsigned char *)(buf+i),
(len-i > 3 ? 3 : len-i), buf2+j);
strcpy(buf2+j, "\r\n");
sk_write(p->sub_socket, buf2, strlen(buf2));
sfree(buf);
sfree(buf2);
}
static void raw_log(Plug plug, int type, SockAddr addr, int port,
const char *error_msg, int error_code)
{
Raw raw = (Raw) plug;
char addrbuf[256], *msg;
sk_getaddr(addr, addrbuf, lenof(addrbuf));
if (type == 0)
msg = dupprintf("Connecting to %s port %d", addrbuf, port);
else
msg = dupprintf("Failed to connect to %s: %s", addrbuf, error_msg);
logevent(raw->frontend, msg);
}
/*
* Called to set up the raw connection.
*
* Returns an error message, or NULL on success.
*
* Also places the canonical host name into `realhost'. It must be
* freed by the caller.
*/
static char *raw_init(char *host, int port, char **realhost, int nodelay)
{
static struct plug_function_table fn_table = {
raw_closing,
raw_receive,
raw_sent
}, *fn_table_ptr = &fn_table;
SockAddr addr;
char *err;
/*
* Try to find host.
*/
{
char buf[200];
sprintf(buf, "Looking up host \"%.170s\"", host);
logevent(buf);
}
addr = sk_namelookup(host, realhost);
if ((err = sk_addr_error(addr)))
return err;
if (port < 0)
port = 23; /* default telnet port */
/*
* Open socket.
*/
{
char buf[200], addrbuf[100];
sk_getaddr(addr, addrbuf, 100);
sprintf(buf, "Connecting to %.100s port %d", addrbuf, port);
logevent(buf);
}
s = new_connection(addr, *realhost, port, 0, 1, nodelay, &fn_table_ptr);
if ((err = sk_socket_error(s)))
return err;
sk_addr_free(addr);
return NULL;
}
Socket new_connection(SockAddr addr,
const char *hostname,
int port,
int privport,
int oobinline,
int nodelay,
int keepalive,
Plug plug,
Conf *conf)
{
static const struct socket_function_table socket_fn_table = {
sk_proxy_plug,
sk_proxy_close,
sk_proxy_write,
sk_proxy_write_oob,
sk_proxy_write_eof,
sk_proxy_flush,
sk_proxy_set_frozen,
sk_proxy_socket_error,
NULL, /* peer_info */
};
static const struct plug_function_table plug_fn_table = {
plug_proxy_log,
plug_proxy_closing,
plug_proxy_receive,
plug_proxy_sent,
plug_proxy_accepting};
if (conf_get_int(conf, CONF_proxy_type) != PROXY_NONE &&
proxy_for_destination(addr, hostname, port, conf)) {
Proxy_Socket ret;
Proxy_Plug pplug;
SockAddr proxy_addr;
char *proxy_canonical_name;
const char *proxy_type;
Socket sret;
int type;
if ((sret = platform_new_connection(addr,
hostname,
port,
privport,
oobinline,
nodelay,
keepalive,
plug,
conf)) != NULL)
return sret;
ret = snew(struct Socket_proxy_tag);
ret->fn = &socket_fn_table;
ret->conf = conf_copy(conf);
ret->plug = plug;
ret->remote_addr = addr; /* will need to be freed on close */
ret->remote_port = port;
ret->error = NULL;
ret->pending_flush = 0;
ret->pending_eof = 0;
ret->freeze = 0;
bufchain_init(&ret->pending_input_data);
bufchain_init(&ret->pending_output_data);
bufchain_init(&ret->pending_oob_output_data);
ret->sub_socket = NULL;
ret->state = PROXY_STATE_NEW;
ret->negotiate = NULL;
type = conf_get_int(conf, CONF_proxy_type);
if (type == PROXY_HTTP) {
ret->negotiate = proxy_http_negotiate;
proxy_type = "HTTP";
} else if (type == PROXY_SOCKS4) {
ret->negotiate = proxy_socks4_negotiate;
proxy_type = "SOCKS 4";
} else if (type == PROXY_SOCKS5) {
ret->negotiate = proxy_socks5_negotiate;
proxy_type = "SOCKS 5";
} else if (type == PROXY_TELNET) {
ret->negotiate = proxy_telnet_negotiate;
proxy_type = "Telnet";
} else {
ret->error = "Proxy error: Unknown proxy method";
return (Socket)ret;
}
{
char *logmsg = dupprintf("Will use %s proxy at %s:%d to connect"
" to %s:%d",
proxy_type,
conf_get_str(conf, CONF_proxy_host),
conf_get_int(conf, CONF_proxy_port),
hostname,
port);
plug_log(plug, 2, NULL, 0, logmsg, 0);
sfree(logmsg);
}
/* create the proxy plug to map calls from the actual
* socket into our proxy socket layer */
pplug = snew(struct Plug_proxy_tag);
pplug->fn = &plug_fn_table;
pplug->proxy_socket = ret;
{
char *logmsg = dns_log_msg(conf_get_str(conf, CONF_proxy_host),
conf_get_int(conf, CONF_addressfamily),
"proxy");
plug_log(plug, 2, NULL, 0, logmsg, 0);
sfree(logmsg);
}
/* look-up proxy */
proxy_addr = sk_namelookup(conf_get_str(conf, CONF_proxy_host),
&proxy_canonical_name,
conf_get_int(conf, CONF_addressfamily));
if (sk_addr_error(proxy_addr) != NULL) {
ret->error = "Proxy error: Unable to resolve proxy host name";
sfree(pplug);
sk_addr_free(proxy_addr);
return (Socket)ret;
}
sfree(proxy_canonical_name);
{
char addrbuf[256], *logmsg;
sk_getaddr(proxy_addr, addrbuf, lenof(addrbuf));
logmsg = dupprintf("Connecting to %s proxy at %s port %d",
proxy_type,
addrbuf,
conf_get_int(conf, CONF_proxy_port));
plug_log(plug, 2, NULL, 0, logmsg, 0);
sfree(logmsg);
}
/* create the actual socket we will be using,
* connected to our proxy server and port.
*/
ret->sub_socket = sk_new(proxy_addr,
conf_get_int(conf, CONF_proxy_port),
privport,
oobinline,
nodelay,
keepalive,
(Plug)pplug);
if (sk_socket_error(ret->sub_socket) != NULL)
return (Socket)ret;
/* start the proxy negotiation process... */
sk_set_frozen(ret->sub_socket, 0);
ret->negotiate(ret, PROXY_CHANGE_NEW);
return (Socket)ret;
}
/*
* This function can accept a NULL pointer as `addr', in which case
* it will only check the host name.
*/
int proxy_for_destination(SockAddr addr,
const char *hostname,
int port,
Conf *conf)
{
int s = 0, e = 0;
char hostip[64];
int hostip_len, hostname_len;
const char *exclude_list;
/*
* Special local connections such as Unix-domain sockets
* unconditionally cannot be proxied, even in proxy-localhost
* mode. There just isn't any way to ask any known proxy type for
* them.
*/
if (addr && sk_address_is_special_local(addr))
return 0; /* do not proxy */
/*
* Check the host name and IP against the hard-coded
* representations of `localhost'.
*/
if (!conf_get_int(conf, CONF_even_proxy_localhost) &&
(sk_hostname_is_local(hostname) || (addr && sk_address_is_local(addr))))
return 0; /* do not proxy */
/* we want a string representation of the IP address for comparisons */
if (addr) {
sk_getaddr(addr, hostip, 64);
hostip_len = strlen(hostip);
} else
hostip_len = 0; /* placate gcc; shouldn't be required */
hostname_len = strlen(hostname);
exclude_list = conf_get_str(conf, CONF_proxy_exclude_list);
/* now parse the exclude list, and see if either our IP
* or hostname matches anything in it.
*/
while (exclude_list[s]) {
while (exclude_list[s] &&
(isspace((unsigned char)exclude_list[s]) || exclude_list[s] == ','))
s++;
if (!exclude_list[s])
break;
e = s;
while (exclude_list[e] &&
(isalnum((unsigned char)exclude_list[e]) || exclude_list[e] == '-' ||
exclude_list[e] == '.' || exclude_list[e] == '*'))
e++;
if (exclude_list[s] == '*') {
/* wildcard at beginning of entry */
if ((addr && strnicmp(hostip + hostip_len - (e - s - 1),
exclude_list + s + 1,
e - s - 1) == 0) ||
strnicmp(hostname + hostname_len - (e - s - 1),
exclude_list + s + 1,
e - s - 1) == 0)
return 0; /* IP/hostname range excluded. do not use proxy. */
} else if (exclude_list[e - 1] == '*') {
/* wildcard at end of entry */
if ((addr && strnicmp(hostip, exclude_list + s, e - s - 1) == 0) ||
strnicmp(hostname, exclude_list + s, e - s - 1) == 0)
return 0; /* IP/hostname range excluded. do not use proxy. */
} else {
/* no wildcard at either end, so let's try an absolute
* match (ie. a specific IP)
*/
if (addr && strnicmp(hostip, exclude_list + s, e - s) == 0)
return 0; /* IP/hostname excluded. do not use proxy. */
if (strnicmp(hostname, exclude_list + s, e - s) == 0)
return 0; /* IP/hostname excluded. do not use proxy. */
}
s = e;
/* Make sure we really have reached the next comma or end-of-string */
while (exclude_list[s] && !isspace((unsigned char)exclude_list[s]) &&
exclude_list[s] != ',')
s++;
}
/* no matches in the exclude list, so use the proxy */
return 1;
}
/*
* Called to set up the rlogin connection.
*
* Returns an error message, or NULL on success.
*
* Also places the canonical host name into `realhost'. It must be
* freed by the caller.
*/
static const char *rlogin_init(void *frontend_handle, void **backend_handle,
Config *cfg,
char *host, int port, char **realhost,
int nodelay, int keepalive)
{
static const struct plug_function_table fn_table = {
rlogin_closing,
rlogin_receive,
rlogin_sent
};
SockAddr addr;
const char *err;
Rlogin rlogin;
rlogin = snew(struct rlogin_tag);
rlogin->fn = &fn_table;
rlogin->s = NULL;
rlogin->frontend = frontend_handle;
rlogin->term_width = cfg->width;
rlogin->term_height = cfg->height;
rlogin->firstbyte = 1;
*backend_handle = rlogin;
/*
* Try to find host.
*/
{
char *buf;
buf = dupprintf("Looking up host \"%s\"", host);
logevent(rlogin->frontend, buf);
sfree(buf);
}
addr = name_lookup(host, port, realhost, cfg);
if ((err = sk_addr_error(addr)) != NULL) {
sk_addr_free(addr);
return err;
}
if (port < 0)
port = 513; /* default rlogin port */
/*
* Open socket.
*/
{
char *buf, addrbuf[100];
sk_getaddr(addr, addrbuf, 100);
buf = dupprintf("Connecting to %s port %d", addrbuf, port);
logevent(rlogin->frontend, buf);
sfree(buf);
}
rlogin->s = new_connection(addr, *realhost, port, 1, 0,
nodelay, keepalive, (Plug) rlogin, cfg);
if ((err = sk_socket_error(rlogin->s)) != NULL)
return err;
/*
* Send local username, remote username, terminal/speed
*/
{
char z = 0;
char *p;
sk_write(rlogin->s, &z, 1);
sk_write(rlogin->s, cfg->localusername,
strlen(cfg->localusername));
sk_write(rlogin->s, &z, 1);
sk_write(rlogin->s, cfg->username,
strlen(cfg->username));
sk_write(rlogin->s, &z, 1);
sk_write(rlogin->s, cfg->termtype,
strlen(cfg->termtype));
sk_write(rlogin->s, "/", 1);
for (p = cfg->termspeed; isdigit((unsigned char)*p); p++) continue;
sk_write(rlogin->s, cfg->termspeed, p - cfg->termspeed);
rlogin->bufsize = sk_write(rlogin->s, &z, 1);
}
return NULL;
}
Socket *new_connection(SockAddr *addr, const char *hostname,
int port, bool privport,
bool oobinline, bool nodelay, bool keepalive,
Plug *plug, Conf *conf)
{
if (conf_get_int(conf, CONF_proxy_type) != PROXY_NONE &&
proxy_for_destination(addr, hostname, port, conf))
{
ProxySocket *ret;
SockAddr *proxy_addr;
char *proxy_canonical_name;
const char *proxy_type;
Socket *sret;
int type;
if ((sret = platform_new_connection(addr, hostname, port, privport,
oobinline, nodelay, keepalive,
plug, conf)) !=
NULL)
return sret;
ret = snew(ProxySocket);
ret->sock.vt = &ProxySocket_sockvt;
ret->plugimpl.vt = &ProxySocket_plugvt;
ret->conf = conf_copy(conf);
ret->plug = plug;
ret->remote_addr = addr; /* will need to be freed on close */
ret->remote_port = port;
ret->error = NULL;
ret->pending_flush = false;
ret->pending_eof = false;
ret->freeze = false;
bufchain_init(&ret->pending_input_data);
bufchain_init(&ret->pending_output_data);
bufchain_init(&ret->pending_oob_output_data);
ret->sub_socket = NULL;
ret->state = PROXY_STATE_NEW;
ret->negotiate = NULL;
type = conf_get_int(conf, CONF_proxy_type);
if (type == PROXY_HTTP) {
ret->negotiate = proxy_http_negotiate;
proxy_type = "HTTP";
} else if (type == PROXY_SOCKS4) {
ret->negotiate = proxy_socks4_negotiate;
proxy_type = "SOCKS 4";
} else if (type == PROXY_SOCKS5) {
ret->negotiate = proxy_socks5_negotiate;
proxy_type = "SOCKS 5";
} else if (type == PROXY_TELNET) {
ret->negotiate = proxy_telnet_negotiate;
proxy_type = "Telnet";
} else {
ret->error = "Proxy error: Unknown proxy method";
return &ret->sock;
}
{
char *logmsg = dupprintf("Will use %s proxy at %s:%d to connect"
" to %s:%d", proxy_type,
conf_get_str(conf, CONF_proxy_host),
conf_get_int(conf, CONF_proxy_port),
hostname, port);
plug_log(plug, 2, NULL, 0, logmsg, 0);
sfree(logmsg);
}
{
char *logmsg = dns_log_msg(conf_get_str(conf, CONF_proxy_host),
conf_get_int(conf, CONF_addressfamily),
"proxy");
plug_log(plug, 2, NULL, 0, logmsg, 0);
sfree(logmsg);
}
/* look-up proxy */
proxy_addr = sk_namelookup(conf_get_str(conf, CONF_proxy_host),
&proxy_canonical_name,
conf_get_int(conf, CONF_addressfamily));
if (sk_addr_error(proxy_addr) != NULL) {
ret->error = "Proxy error: Unable to resolve proxy host name";
sk_addr_free(proxy_addr);
return &ret->sock;
}
sfree(proxy_canonical_name);
{
char addrbuf[256], *logmsg;
sk_getaddr(proxy_addr, addrbuf, lenof(addrbuf));
logmsg = dupprintf("Connecting to %s proxy at %s port %d",
proxy_type, addrbuf,
conf_get_int(conf, CONF_proxy_port));
plug_log(plug, 2, NULL, 0, logmsg, 0);
sfree(logmsg);
}
/* create the actual socket we will be using,
* connected to our proxy server and port.
*/
ret->sub_socket = sk_new(proxy_addr,
conf_get_int(conf, CONF_proxy_port),
privport, oobinline,
nodelay, keepalive, &ret->plugimpl);
if (sk_socket_error(ret->sub_socket) != NULL)
return &ret->sock;
/* start the proxy negotiation process... */
sk_set_frozen(ret->sub_socket, 0);
ret->negotiate(ret, PROXY_CHANGE_NEW);
return &ret->sock;
}
/* no proxy, so just return the direct socket */
return sk_new(addr, port, privport, oobinline, nodelay, keepalive, plug);
}
/*
* Called to set up the rlogin connection.
*
* Returns an error message, or NULL on success.
*
* Also places the canonical host name into `realhost'. It must be
* freed by the caller.
*/
static char *rlogin_init(char *host, int port, char **realhost, int nodelay)
{
static struct plug_function_table fn_table = {
rlogin_closing,
rlogin_receive,
rlogin_sent
}, *fn_table_ptr = &fn_table;
SockAddr addr;
char *err;
/*
* Try to find host.
*/
{
char buf[200];
sprintf(buf, "Looking up host \"%.170s\"", host);
logevent(buf);
}
addr = sk_namelookup(host, realhost);
if ((err = sk_addr_error(addr)))
return err;
if (port < 0)
port = 513; /* default rlogin port */
/*
* Open socket.
*/
{
char buf[200], addrbuf[100];
sk_getaddr(addr, addrbuf, 100);
sprintf(buf, "Connecting to %.100s port %d", addrbuf, port);
logevent(buf);
}
s = sk_new(addr, port, 1, 0, nodelay, &fn_table_ptr);
if ((err = sk_socket_error(s)))
return err;
sk_addr_free(addr);
/*
* Send local username, remote username, terminal/speed
*/
{
char z = 0;
char *p;
sk_write(s, &z, 1);
sk_write(s, cfg.localusername, strlen(cfg.localusername));
sk_write(s, &z, 1);
sk_write(s, cfg.username, strlen(cfg.username));
sk_write(s, &z, 1);
sk_write(s, cfg.termtype, strlen(cfg.termtype));
sk_write(s, "/", 1);
for (p = cfg.termspeed; isdigit(*p); p++);
sk_write(s, cfg.termspeed, p - cfg.termspeed);
rlogin_bufsize = sk_write(s, &z, 1);
}
return NULL;
}
