diff options
Diffstat (limited to 'src/feature/relay/transport_config.c')
| -rw-r--r-- | src/feature/relay/transport_config.c | 307 |
1 files changed, 307 insertions, 0 deletions
diff --git a/src/feature/relay/transport_config.c b/src/feature/relay/transport_config.c new file mode 100644 index 0000000000..7dcce70e30 --- /dev/null +++ b/src/feature/relay/transport_config.c @@ -0,0 +1,307 @@ +/* Copyright (c) 2001 Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2020, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * @file transport_config.c + * @brief Code to interpret the user's configuration of Tor's server + * pluggable transports. + **/ + +#include "orconfig.h" +#define RELAY_TRANSPORT_CONFIG_PRIVATE +#include "feature/relay/transport_config.h" + +#include "lib/encoding/confline.h" +#include "lib/encoding/keyval.h" + +#include "lib/container/smartlist.h" + +/* Required for dirinfo_type_t in or_options_t */ +#include "core/or/or.h" +#include "app/config/config.h" + +#include "feature/relay/ext_orport.h" +#include "feature/relay/routermode.h" + +/* Copied from config.c, we will refactor later in 29211. */ +#define REJECT(arg) \ + STMT_BEGIN *msg = tor_strdup(arg); return -1; STMT_END + +/** Given a ServerTransportListenAddr <b>line</b>, return its + * <address:port> string. Return NULL if the line was not + * well-formed. + * + * If <b>transport</b> is set, return NULL if the line is not + * referring to <b>transport</b>. + * + * The returned string is allocated on the heap and it's the + * responsibility of the caller to free it. */ +static char * +get_bindaddr_from_transport_listen_line(const char *line, + const char *transport) +{ + smartlist_t *items = NULL; + const char *parsed_transport = NULL; + char *addrport = NULL; + tor_addr_t addr; + uint16_t port = 0; + + items = smartlist_new(); + smartlist_split_string(items, line, NULL, + SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, -1); + + if (smartlist_len(items) < 2) { + log_warn(LD_CONFIG,"Too few arguments on ServerTransportListenAddr line."); + goto err; + } + + parsed_transport = smartlist_get(items, 0); + addrport = tor_strdup(smartlist_get(items, 1)); + + /* If 'transport' is given, check if it matches the one on the line */ + if (transport && strcmp(transport, parsed_transport)) + goto err; + + /* Validate addrport */ + if (tor_addr_port_parse(LOG_WARN, addrport, &addr, &port, -1)<0) { + log_warn(LD_CONFIG, "Error parsing ServerTransportListenAddr " + "address '%s'", addrport); + goto err; + } + + goto done; + + err: + tor_free(addrport); + addrport = NULL; + + done: + SMARTLIST_FOREACH(items, char*, s, tor_free(s)); + smartlist_free(items); + + return addrport; +} + +/** Given the name of a pluggable transport in <b>transport</b>, check + * the configuration file to see if the user has explicitly asked for + * it to listen on a specific port. Return a <address:port> string if + * so, otherwise NULL. */ +char * +pt_get_bindaddr_from_config(const char *transport) +{ + config_line_t *cl; + const or_options_t *options = get_options(); + + for (cl = options->ServerTransportListenAddr; cl; cl = cl->next) { + char *bindaddr = + get_bindaddr_from_transport_listen_line(cl->value, transport); + if (bindaddr) + return bindaddr; + } + + return NULL; +} + +/** Given a ServerTransportOptions <b>line</b>, return a smartlist + * with the options. Return NULL if the line was not well-formed. + * + * If <b>transport</b> is set, return NULL if the line is not + * referring to <b>transport</b>. + * + * The returned smartlist and its strings are allocated on the heap + * and it's the responsibility of the caller to free it. */ +STATIC smartlist_t * +get_options_from_transport_options_line(const char *line, + const char *transport) +{ + smartlist_t *items = smartlist_new(); + smartlist_t *pt_options = smartlist_new(); + const char *parsed_transport = NULL; + + smartlist_split_string(items, line, NULL, + SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, -1); + + if (smartlist_len(items) < 2) { + log_warn(LD_CONFIG,"Too few arguments on ServerTransportOptions line."); + goto err; + } + + parsed_transport = smartlist_get(items, 0); + /* If 'transport' is given, check if it matches the one on the line */ + if (transport && strcmp(transport, parsed_transport)) + goto err; + + SMARTLIST_FOREACH_BEGIN(items, const char *, option) { + if (option_sl_idx == 0) /* skip the transport field (first field)*/ + continue; + + /* validate that it's a k=v value */ + if (!string_is_key_value(LOG_WARN, option)) { + log_warn(LD_CONFIG, "%s is not a k=v value.", escaped(option)); + goto err; + } + + /* add it to the options smartlist */ + smartlist_add_strdup(pt_options, option); + log_debug(LD_CONFIG, "Added %s to the list of options", escaped(option)); + } SMARTLIST_FOREACH_END(option); + + goto done; + + err: + SMARTLIST_FOREACH(pt_options, char*, s, tor_free(s)); + smartlist_free(pt_options); + pt_options = NULL; + + done: + SMARTLIST_FOREACH(items, char*, s, tor_free(s)); + smartlist_free(items); + + return pt_options; +} + +/** Given the name of a pluggable transport in <b>transport</b>, check + * the configuration file to see if the user has asked us to pass any + * parameters to the pluggable transport. Return a smartlist + * containing the parameters, otherwise NULL. */ +smartlist_t * +pt_get_options_for_server_transport(const char *transport) +{ + config_line_t *cl; + const or_options_t *options = get_options(); + + for (cl = options->ServerTransportOptions; cl; cl = cl->next) { + smartlist_t *options_sl = + get_options_from_transport_options_line(cl->value, transport); + if (options_sl) + return options_sl; + } + + return NULL; +} + +/** + * Legacy validation/normalization function for the server transport options. + * Uses old_options as the previous options. + * + * Returns 0 on success, returns -1 and sets *msg to a newly allocated string + * on error. + */ +int +options_validate_server_transport(const or_options_t *old_options, + or_options_t *options, + char **msg) +{ + (void)old_options; + + if (BUG(!options)) + return -1; + + if (BUG(!msg)) + return -1; + + config_line_t *cl; + + if (options->ServerTransportPlugin && !server_mode(options)) { + log_notice(LD_GENERAL, "Tor is not configured as a relay but you specified" + " a ServerTransportPlugin line (%s). The ServerTransportPlugin " + "line will be ignored.", + escaped(options->ServerTransportPlugin->value)); + } + + if (options->ServerTransportListenAddr && !options->ServerTransportPlugin) { + log_notice(LD_GENERAL, "You need at least a single managed-proxy to " + "specify a transport listen address. The " + "ServerTransportListenAddr line will be ignored."); + } + + for (cl = options->ServerTransportPlugin; cl; cl = cl->next) { + if (pt_parse_transport_line(options, cl->value, 1, 1) < 0) + REJECT("Invalid server transport line. See logs for details."); + } + + for (cl = options->ServerTransportListenAddr; cl; cl = cl->next) { + /** If get_bindaddr_from_transport_listen_line() fails with + 'transport' being NULL, it means that something went wrong + while parsing the ServerTransportListenAddr line. */ + char *bindaddr = get_bindaddr_from_transport_listen_line(cl->value, NULL); + if (!bindaddr) + REJECT("ServerTransportListenAddr did not parse. See logs for details."); + tor_free(bindaddr); + } + + for (cl = options->ServerTransportOptions; cl; cl = cl->next) { + /** If get_options_from_transport_options_line() fails with + 'transport' being NULL, it means that something went wrong + while parsing the ServerTransportOptions line. */ + smartlist_t *options_sl = + get_options_from_transport_options_line(cl->value, NULL); + if (!options_sl) + REJECT("ServerTransportOptions did not parse. See logs for details."); + + SMARTLIST_FOREACH(options_sl, char *, cp, tor_free(cp)); + smartlist_free(options_sl); + } + + return 0; +} + +/** Fetch the active option list, and take server pluggable transport actions + * based on it. All of the things we do should survive being done repeatedly. + * If present, <b>old_options</b> contains the previous value of the options. + * + * Return 0 if all goes well, return -1 if it's time to die. + * + * Note: We haven't moved all the "act on new configuration" logic + * into the options_act* functions yet. Some is still in do_hup() and other + * places. + */ +int +options_act_server_transport(const or_options_t *old_options) +{ + (void)old_options; + + config_line_t *cl; + const or_options_t *options = get_options(); + int running_tor = options->command == CMD_RUN_TOR; + + /* If we are a bridge with a pluggable transport proxy but no + Extended ORPort, inform the user that they are missing out. */ + if (options->ServerTransportPlugin && + !options->ExtORPort_lines) { + log_notice(LD_CONFIG, "We use pluggable transports but the Extended " + "ORPort is disabled. Tor and your pluggable transports proxy " + "communicate with each other via the Extended ORPort so it " + "is suggested you enable it: it will also allow your Bridge " + "to collect statistics about its clients that use pluggable " + "transports. Please enable it using the ExtORPort torrc option " + "(e.g. set 'ExtORPort auto')."); + } + + /* If we have an ExtORPort, initialize its auth cookie. */ + if (running_tor && + init_ext_or_cookie_authentication(!!options->ExtORPort_lines) < 0) { + log_warn(LD_CONFIG,"Error creating Extended ORPort cookie file."); + return -1; + } + + if (!options->DisableNetwork) { + if (options->ServerTransportPlugin) { + for (cl = options->ServerTransportPlugin; cl; cl = cl->next) { + if (pt_parse_transport_line(options, cl->value, 0, 1) < 0) { + // LCOV_EXCL_START + log_warn(LD_BUG, + "Previously validated ServerTransportPlugin line " + "could not be added!"); + return -1; + // LCOV_EXCL_STOP + } + } + } + } + + return 0; +} |