X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/8eebd22198133e95ce25af1dd15dead0a5389371..9bf696b19e8cdceb6fe9d3e5a9683f2a04d8bfe1:/proxy.c diff --git a/proxy.c b/proxy.c index b773f251..e8f0fdc5 100644 --- a/proxy.c +++ b/proxy.c @@ -21,21 +21,12 @@ void proxy_activate (Proxy_Socket p) void *data; int len; - p->lock_close = - p->lock_write = - p->lock_write_oob = - p->lock_receive = - p->lock_flush = - p->lock_closing = - p->lock_sent = - p->lock_accepting = - p->lock_freeze = 1; - p->state = PROXY_STATE_ACTIVE; /* let's try to keep extra receive events from coming through */ sk_set_frozen(p->sub_socket, 1); + /* send buffered OOB writes */ while (bufchain_size(&p->pending_oob_output_data) > 0) { bufchain_prefix(&p->pending_oob_output_data, &data, &len); sk_write_oob(p->sub_socket, data, len); @@ -43,6 +34,7 @@ void proxy_activate (Proxy_Socket p) } bufchain_clear(&p->pending_oob_output_data); + /* send buffered normal writes */ while (bufchain_size(&p->pending_output_data) > 0) { bufchain_prefix(&p->pending_output_data, &data, &len); sk_write(p->sub_socket, data, len); @@ -50,28 +42,21 @@ void proxy_activate (Proxy_Socket p) } bufchain_clear(&p->pending_output_data); - p->lock_write_oob = 0; - p->lock_write = 0; - + /* if we were asked to flush the output during + * the proxy negotiation process, do so now. + */ if (p->pending_flush) sk_flush(p->sub_socket); - p->lock_flush = 0; + /* forward buffered recv data to the backend */ while (bufchain_size(&p->pending_input_data) > 0) { bufchain_prefix(&p->pending_input_data, &data, &len); plug_receive(p->plug, 0, data, len); bufchain_consume(&p->pending_input_data, len); } bufchain_clear(&p->pending_input_data); - p->lock_receive = 0; /* now set the underlying socket to whatever freeze state they wanted */ sk_set_frozen(p->sub_socket, p->freeze); - p->lock_freeze = 0; - - p->lock_sent = 0; - p->lock_accepting = 0; - p->lock_closing = 0; - p->lock_close = 0; } /* basic proxy socket functions */ @@ -89,7 +74,6 @@ static void sk_proxy_close (Socket s) { Proxy_Socket ps = (Proxy_Socket) s; - while (ps->lock_close) ; sk_close(ps->sub_socket); sfree(ps); } @@ -98,7 +82,6 @@ static int sk_proxy_write (Socket s, char *data, int len) { Proxy_Socket ps = (Proxy_Socket) s; - while (ps->lock_write) ; if (ps->state != PROXY_STATE_ACTIVE) { bufchain_add(&ps->pending_output_data, data, len); return bufchain_size(&ps->pending_output_data); @@ -110,7 +93,6 @@ static int sk_proxy_write_oob (Socket s, char *data, int len) { Proxy_Socket ps = (Proxy_Socket) s; - while (ps->lock_write_oob) ; if (ps->state != PROXY_STATE_ACTIVE) { bufchain_clear(&ps->pending_output_data); bufchain_clear(&ps->pending_oob_output_data); @@ -124,7 +106,6 @@ static void sk_proxy_flush (Socket s) { Proxy_Socket ps = (Proxy_Socket) s; - while (ps->lock_flush) ; if (ps->state != PROXY_STATE_ACTIVE) { ps->pending_flush = 1; return; @@ -148,7 +129,6 @@ static void sk_proxy_set_frozen (Socket s, int is_frozen) { Proxy_Socket ps = (Proxy_Socket) s; - while (ps->lock_freeze) ; if (ps->state != PROXY_STATE_ACTIVE) { ps->freeze = is_frozen; return; @@ -173,7 +153,6 @@ static int plug_proxy_closing (Plug p, char *error_msg, Proxy_Plug pp = (Proxy_Plug) p; Proxy_Socket ps = pp->proxy_socket; - while (ps->lock_closing) ; if (ps->state != PROXY_STATE_ACTIVE) { ps->closing_error_msg = error_msg; ps->closing_error_code = error_code; @@ -189,7 +168,6 @@ static int plug_proxy_receive (Plug p, int urgent, char *data, int len) Proxy_Plug pp = (Proxy_Plug) p; Proxy_Socket ps = pp->proxy_socket; - while (ps->lock_receive) ; if (ps->state != PROXY_STATE_ACTIVE) { /* we will lose the urgentness of this data, but since most, * if not all, of this data will be consumed by the negotiation @@ -209,7 +187,6 @@ static void plug_proxy_sent (Plug p, int bufsize) Proxy_Plug pp = (Proxy_Plug) p; Proxy_Socket ps = pp->proxy_socket; - while (ps->lock_sent) ; if (ps->state != PROXY_STATE_ACTIVE) { ps->sent_bufsize = bufsize; ps->negotiate(ps, PROXY_CHANGE_SENT); @@ -223,7 +200,6 @@ static int plug_proxy_accepting (Plug p, void *sock) Proxy_Plug pp = (Proxy_Plug) p; Proxy_Socket ps = pp->proxy_socket; - while (ps->lock_accepting) ; if (ps->state != PROXY_STATE_ACTIVE) { ps->accepting_sock = sock; return ps->negotiate(ps, PROXY_CHANGE_ACCEPTING); @@ -340,15 +316,6 @@ Socket new_connection(SockAddr addr, char *hostname, bufchain_init(&ret->pending_output_data); bufchain_init(&ret->pending_oob_output_data); - ret->lock_close = - ret->lock_write = - ret->lock_write_oob = - ret->lock_receive = - ret->lock_flush = - ret->lock_closing = - ret->lock_sent = - ret->lock_accepting = 0; - ret->sub_socket = NULL; ret->state = PROXY_STATE_NEW; @@ -451,9 +418,9 @@ int proxy_http_negotiate (Proxy_Socket p, int change) * for this proxy method, it's just a simple HTTP * request */ - char buf[1024], dest[21]; + char buf[256], dest[64]; - sk_getaddr(p->remote_addr, dest, 20); + sk_getaddr(p->remote_addr, dest, 64); sprintf(buf, "CONNECT %s:%i HTTP/1.1\r\nHost: %s:%i\r\n\r\n", dest, p->remote_port, dest, p->remote_port); @@ -579,7 +546,7 @@ int proxy_socks_negotiate (Proxy_Socket p, int change) } /* ---------------------------------------------------------------------- - * `Telnet' proxy type (as yet unimplemented). + * `Telnet' proxy type. * * (This is for ad-hoc proxies where you connect to the proxy's * telnet port and send a command such as `connect host port'. The @@ -589,6 +556,206 @@ int proxy_socks_negotiate (Proxy_Socket p, int change) int proxy_telnet_negotiate (Proxy_Socket p, int change) { - p->error = "Network error: Telnet proxy implementation is incomplete"; + if (p->state == PROXY_CHANGE_NEW) { + + int so = 0, eo = 0; + + /* we need to escape \\, \%, \r, \n, \t, \x??, \0???, + * %%, %host, and %port + */ + + while (cfg.proxy_telnet_command[eo] != 0) { + + /* scan forward until we hit end-of-line, + * or an escape character (\ or %) */ + while (cfg.proxy_telnet_command[eo] != 0 && + cfg.proxy_telnet_command[eo] != '%' && + cfg.proxy_telnet_command[eo] != '\\') eo++; + + /* if we hit eol, break out of our escaping loop */ + if (cfg.proxy_telnet_command[eo] == 0) break; + + /* if there was any unescaped text before the escape + * character, send that now */ + if (eo != so) { + sk_write(p->sub_socket, + cfg.proxy_telnet_command + so, eo - so); + } + + so = eo++; + + /* if the escape character was the last character of + * the line, we'll just stop and send it. */ + if (cfg.proxy_telnet_command[eo] == 0) break; + + if (cfg.proxy_telnet_command[so] == '\\') { + + /* we recognize \\, \%, \r, \n, \t, \x??. + * anything else, we just send unescaped (including the \). + */ + + switch (cfg.proxy_telnet_command[eo]) { + + case '\\': + sk_write(p->sub_socket, "\\", 1); + eo++; + break; + + case '%': + sk_write(p->sub_socket, "%%", 1); + eo++; + break; + + case 'r': + sk_write(p->sub_socket, "\r", 1); + eo++; + break; + + case 'n': + sk_write(p->sub_socket, "\n", 1); + eo++; + break; + + case 't': + sk_write(p->sub_socket, "\t", 1); + eo++; + break; + + case 'x': + case 'X': + { + /* escaped hexadecimal value (ie. \xff) */ + unsigned char v = 0; + int i = 0; + + for (;;) { + eo++; + if (cfg.proxy_telnet_command[eo] >= '0' && + cfg.proxy_telnet_command[eo] <= '9') + v += cfg.proxy_telnet_command[eo] - '0'; + else if (cfg.proxy_telnet_command[eo] >= 'a' && + cfg.proxy_telnet_command[eo] <= 'f') + v += cfg.proxy_telnet_command[eo] - 'a' + 10; + else if (cfg.proxy_telnet_command[eo] >= 'A' && + cfg.proxy_telnet_command[eo] <= 'F') + v += cfg.proxy_telnet_command[eo] - 'A' + 10; + else { + /* non hex character, so we abort and just + * send the whole thing unescaped (including \x) + */ + sk_write(p->sub_socket, "\\", 1); + eo = so + 1; + break; + } + + /* we only extract two hex characters */ + if (i == 1) { + sk_write(p->sub_socket, &v, 1); + eo++; + break; + } + + i++; + v <<= 4; + } + } + break; + + default: + sk_write(p->sub_socket, + cfg.proxy_telnet_command + so, 2); + eo++; + break; + } + } else { + + /* % escape. we recognize %%, %host, %port. anything else, + * we just send unescaped (including the %). */ + + if (cfg.proxy_telnet_command[eo] == '%') { + sk_write(p->sub_socket, "%", 1); + eo++; + } + else if (strnicmp(cfg.proxy_telnet_command + eo, + "host", 4) == 0) { + char dest[64]; + sk_getaddr(p->remote_addr, dest, 64); + sk_write(p->sub_socket, dest, strlen(dest)); + eo += 4; + } + else if (strnicmp(cfg.proxy_telnet_command + eo, + "port", 4) == 0) { + char port[8]; + sprintf(port, "%i", p->remote_port); + sk_write(p->sub_socket, port, strlen(port)); + eo += 4; + } + else { + /* we don't escape this, so send the % now, and + * don't advance eo, so that we'll consider the + * text immediately following the % as unescaped. + */ + sk_write(p->sub_socket, "%", 1); + } + } + + /* resume scanning for additional escapes after this one. */ + so = eo; + } + + /* if there is any unescaped text at the end of the line, send it */ + if (eo != so) { + sk_write(p->sub_socket, cfg.proxy_telnet_command + so, eo - so); + } + + p->state = 1; + + return 0; + } + + if (change == PROXY_CHANGE_CLOSING) { + /* if our proxy negotiation process involves closing and opening + * new sockets, then we would want to intercept this closing + * callback when we were expecting it. if we aren't anticipating + * a socket close, then some error must have occurred. we'll + * just pass those errors up to the backend. + */ + return plug_closing(p->plug, p->closing_error_msg, + p->closing_error_code, + p->closing_calling_back); + } + + if (change == PROXY_CHANGE_SENT) { + /* some (or all) of what we wrote to the proxy was sent. + * we don't do anything new, however, until we receive the + * proxy's response. we might want to set a timer so we can + * timeout the proxy negotiation after a while... + */ + return 0; + } + + if (change == PROXY_CHANGE_ACCEPTING) { + /* we should _never_ see this, as we are using our socket to + * connect to a proxy, not accepting inbound connections. + * what should we do? close the socket with an appropriate + * error message? + */ + return plug_accepting(p->plug, p->accepting_sock); + } + + if (change == PROXY_CHANGE_RECEIVE) { + /* we have received data from the underlying socket, which + * we'll need to parse, process, and respond to appropriately. + */ + + /* we're done */ + proxy_activate(p); + /* proxy activate will have dealt with + * whatever is left of the buffer */ + return 1; + } + + plug_closing(p->plug, "Network error: Unexpected proxy error", + PROXY_ERROR_UNEXPECTED, 0); return 0; }