config: Move server transport config into the relay module

This commit:
* creates feature/relay/transport_config.[ch],
* moves server transport config checks into them,
* exposes some code from src/app/config.c
  (we'll refactor it later in 29211), and
* adds thin wrappers to make the moved code compile.

No functional changes: the moved code is still enabled,
even if the relay module is disabled. (Some of the checks
are re-ordered, so the order of some warnings may change.)

Part of 32213.

1 files changed, 4 insertions, 195 deletions

diff --git a/src/app/config/config.c b/src/app/config/config.c
index 3d6ba00efa..4ec38e30c7 100644
--- a/src/app/config/config.c
+++ b/src/app/config/config.c
@@ -103,6 +103,7 @@
 #include "feature/relay/ext_orport.h"
 #include "feature/relay/routermode.h"
 #include "feature/relay/relay_config.h"
+#include "feature/relay/transport_config.h"
 #include "feature/rend/rendclient.h"
 #include "feature/rend/rendservice.h"
 #include "lib/geoip/geoip.h"
@@ -827,8 +828,6 @@ static int options_transition_affects_workers(
       const or_options_t *old_options, const or_options_t *new_options);
 static int options_transition_affects_descriptor(
       const or_options_t *old_options, const or_options_t *new_options);
-static char *get_bindaddr_from_transport_listen_line(const char *line,
-                                                     const char *transport);
 static int parse_ports(or_options_t *options, int validate_only,
                               char **msg_out, int *n_ports_out,
                               int *world_writable_control_socket);
@@ -4108,46 +4107,8 @@ options_validate_cb(const void *old_options_, void *options_, char **msg)
       REJECT("Invalid client transport line. See logs for details.");
   }
 
-  for (cl = options->ServerTransportPlugin; cl; cl = cl->next) {
-    if (parse_transport_line(options, cl->value, 1, 1) < 0)
-      REJECT("Invalid server transport line. See logs for details.");
-  }
-
-  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));
-  }
-
-  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);
-  }
-
-  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->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);
-  }
+  if (options_validate_server_transport(old_options, options, msg) < 0)
+    return -1;
 
   if (options->ConstrainedSockets) {
     /* If the user wants to constrain socket buffer use, make sure the desired
@@ -5564,8 +5525,7 @@ parse_bridge_line(const char *line)
  * our internal transport list.
  * - If it's a managed proxy line, launch the managed proxy.
  */
-
-STATIC int
+int
 parse_transport_line(const or_options_t *options,
                      const char *line, int validate_only,
                      int server)
@@ -5759,157 +5719,6 @@ parse_transport_line(const or_options_t *options,
   return r;
 }
 
-/** 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 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. */
-smartlist_t *
-get_options_from_transport_options_line(const char *line,const char *transport)
-{
-  smartlist_t *items = smartlist_new();
-  smartlist_t *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(options, option);
-    log_debug(LD_CONFIG, "Added %s to the list of options", escaped(option));
-  } SMARTLIST_FOREACH_END(option);
-
-  goto done;
-
- err:
-  SMARTLIST_FOREACH(options, char*, s, tor_free(s));
-  smartlist_free(options);
-  options = NULL;
-
- done:
-  SMARTLIST_FOREACH(items, char*, s, tor_free(s));
-  smartlist_free(items);
-
-  return options;
-}
-
-/** 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 *
-get_transport_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 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 *
-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;
-}
-
 /** Read the contents of a DirAuthority line from <b>line</b>. If
  * <b>validate_only</b> is 0, and the line is well-formed, and it
  * shares any bits with <b>required_type</b> or <b>required_type</b>