o Handle servers with dynamic IP addresses: don't replace

  options->Address with the resolved one at startup.
  o detect our address right before we make a routerinfo each time.
o external IP vs bind-IP. Already done, just use options->Address.
o OutboundBindAddress config option, to bind to a specific
  IP address for outgoing connect()s.


svn:r2241

4 files changed, 65 insertions, 30 deletions

diff --git a/src/or/config.c b/src/or/config.c
index 067ab4ba64..8a28e02c62 100644
--- a/src/or/config.c
+++ b/src/or/config.c
@@ -213,6 +213,11 @@ static int config_assign(or_options_t *options, struct config_line_t *list) {
 
     config_compare(list, "Group",          CONFIG_TYPE_STRING, &options->Group) ||
 
+    config_compare(list, "HiddenServiceDir", CONFIG_TYPE_LINELIST, &options->RendConfigLines)||
+    config_compare(list, "HiddenServicePort", CONFIG_TYPE_LINELIST, &options->RendConfigLines)||
+    config_compare(list, "HiddenServiceNodes", CONFIG_TYPE_LINELIST, &options->RendConfigLines)||
+    config_compare(list, "HiddenServiceExcludeNodes", CONFIG_TYPE_LINELIST, &options->RendConfigLines)||
+
     config_compare(list, "IgnoreVersion",  CONFIG_TYPE_BOOL, &options->IgnoreVersion) ||
 
     config_compare(list, "KeepalivePeriod",CONFIG_TYPE_INT, &options->KeepalivePeriod) ||
@@ -230,12 +235,14 @@ static int config_assign(or_options_t *options, struct config_line_t *list) {
 
     config_compare(list, "ORPort",         CONFIG_TYPE_INT, &options->ORPort) ||
     config_compare(list, "ORBindAddress",  CONFIG_TYPE_LINELIST, &options->ORBindAddress) ||
+    config_compare(list, "OutboundBindAddress",CONFIG_TYPE_STRING, &options->OutboundBindAddress) ||
 
     config_compare(list, "PidFile",        CONFIG_TYPE_STRING, &options->PidFile) ||
     config_compare(list, "PathlenCoinWeight",CONFIG_TYPE_DOUBLE, &options->PathlenCoinWeight) ||
 
     config_compare(list, "RouterFile",     CONFIG_TYPE_STRING, &options->RouterFile) ||
     config_compare(list, "RunAsDaemon",    CONFIG_TYPE_BOOL, &options->RunAsDaemon) ||
+    config_compare(list, "RunTesting",     CONFIG_TYPE_BOOL, &options->RunTesting) ||
     config_compare(list, "RecommendedVersions",CONFIG_TYPE_STRING, &options->RecommendedVersions) ||
     config_compare(list, "RendNodes",      CONFIG_TYPE_STRING, &options->RendNodes) ||
     config_compare(list, "RendExcludeNodes",CONFIG_TYPE_STRING, &options->RendExcludeNodes) ||
@@ -246,12 +253,9 @@ static int config_assign(or_options_t *options, struct config_line_t *list) {
 
     config_compare(list, "TrafficShaping", CONFIG_TYPE_BOOL, &options->TrafficShaping) ||
 
-    config_compare(list, "User",           CONFIG_TYPE_STRING, &options->User) ||
-    config_compare(list, "RunTesting",     CONFIG_TYPE_BOOL, &options->RunTesting) ||
-    config_compare(list, "HiddenServiceDir", CONFIG_TYPE_LINELIST, &options->RendConfigLines)||
-    config_compare(list, "HiddenServicePort", CONFIG_TYPE_LINELIST, &options->RendConfigLines)||
-    config_compare(list, "HiddenServiceNodes", CONFIG_TYPE_LINELIST, &options->RendConfigLines)||
-    config_compare(list, "HiddenServiceExcludeNodes", CONFIG_TYPE_LINELIST, &options->RendConfigLines)
+    config_compare(list, "User",           CONFIG_TYPE_STRING, &options->User)
+
+
     ) {
       /* then we're ok. it matched something. */
     } else {
@@ -422,31 +426,34 @@ static void print_usage(void) {
 /**
  * Adjust <b>options</b> to contain a reasonable value for Address.
  */
-static int resolve_my_address(or_options_t *options) {
+int resolve_my_address(const char *address, uint32_t *addr) {
   struct in_addr in;
   struct hostent *rent;
-  char localhostname[256];
+  char hostname[256];
   int explicit_ip=1;
 
-  if(!options->Address) { /* then we need to guess our address */
+  tor_assert(addr);
+
+  if(address) {
+    strlcpy(hostname,address,sizeof(hostname));
+  } else { /* then we need to guess our address */
     explicit_ip = 0; /* it's implicit */
 
-    if(gethostname(localhostname,sizeof(localhostname)) < 0) {
+    if(gethostname(hostname,sizeof(hostname)) < 0) {
       log_fn(LOG_WARN,"Error obtaining local hostname");
       return -1;
     }
-    options->Address = tor_strdup(localhostname);
-    log_fn(LOG_DEBUG,"Guessed local host name as '%s'",options->Address);
+    log_fn(LOG_DEBUG,"Guessed local host name as '%s'",hostname);
   }
 
-  /* now we know options->Address is set. resolve it and keep only the IP */
+  /* now we know hostname. resolve it and keep only the IP */
 
-  if(tor_inet_aton(options->Address, &in) == 0) {
+  if(tor_inet_aton(hostname, &in) == 0) {
     /* then we have to resolve it */
     explicit_ip = 0;
-    rent = (struct hostent *)gethostbyname(options->Address);
+    rent = (struct hostent *)gethostbyname(hostname);
     if (!rent) {
-      log_fn(LOG_WARN,"Could not resolve Address %s. Failing.", options->Address);
+      log_fn(LOG_WARN,"Could not resolve local Address %s. Failing.", hostname);
       return -1;
     }
     tor_assert(rent->h_length == 4);
@@ -455,12 +462,11 @@ static int resolve_my_address(or_options_t *options) {
   if(!explicit_ip && is_internal_IP(htonl(in.s_addr))) {
     log_fn(LOG_WARN,"Address '%s' resolves to private IP '%s'. "
            "Please set the Address config option to be the IP you want to use.",
-           options->Address, inet_ntoa(in));
+           hostname, inet_ntoa(in));
     return -1;
   }
-  tor_free(options->Address);
-  options->Address = tor_strdup(inet_ntoa(in));
-  log_fn(LOG_DEBUG,"Resolved Address to %s.", options->Address);
+  log_fn(LOG_DEBUG,"Resolved Address to %s.", inet_ntoa(in));
+  *addr = ntohl(in.s_addr);
   return 0;
 }
 
@@ -513,6 +519,7 @@ static void free_options(or_options_t *options) {
   tor_free(options->ExcludeNodes);
   tor_free(options->RendNodes);
   tor_free(options->RendExcludeNodes);
+  tor_free(options->OutboundBindAddress);
   tor_free(options->RecommendedVersions);
   tor_free(options->User);
   tor_free(options->Group);
@@ -540,6 +547,7 @@ static void init_options(or_options_t *options) {
   options->SocksBindAddress = NULL;
   options->ORBindAddress = NULL;
   options->DirBindAddress = NULL;
+  options->OutboundBindAddress = NULL;
   options->RecommendedVersions = NULL;
   options->PidFile = NULL; // tor_strdup("tor.pid");
   options->DataDirectory = NULL;
@@ -696,8 +704,10 @@ int getconfig(int argc, char **argv, or_options_t *options) {
     }
   }
 
-  if(server_mode()) { /* get an IP for ourselves */
-    if(resolve_my_address(options) < 0)
+  if(server_mode()) {
+    /* confirm that our address isn't broken, so we can complain now */
+    uint32_t tmp;
+    if(resolve_my_address(options->Address, &tmp) < 0)
       result = -1;
   }
 
diff --git a/src/or/connection.c b/src/or/connection.c
index f37cae100a..74da0d6d07 100644
--- a/src/or/connection.c
+++ b/src/or/connection.c
@@ -482,6 +482,25 @@ int connection_connect(connection_t *conn, char *address, uint32_t addr, uint16_
            tor_socket_strerror(tor_socket_errno(-1)));
     return -1;
   }
+
+  if (options.OutboundBindAddress) {
+    struct sockaddr_in ext_addr;
+
+    memset(&ext_addr, 0, sizeof(ext_addr));
+    ext_addr.sin_family = AF_INET;
+    ext_addr.sin_port = 0;
+    if (!tor_inet_aton(options.OutboundBindAddress, &ext_addr.sin_addr)) {
+      log_fn(LOG_WARN,"Outbound bind address '%s' didn't parse. Ignoring.",
+             options.OutboundBindAddress);
+    } else {
+      if(bind(s, (struct sockaddr*)&ext_addr, sizeof(ext_addr) < 0)) {
+        log_fn(LOG_WARN,"Error binding network socket: %s",
+               tor_socket_strerror(tor_socket_errno(s)));
+        return -1;
+      }
+    }
+  }
+
   set_socket_nonblocking(s);
 
   memset(&dest_addr,0,sizeof(dest_addr));
diff --git a/src/or/or.h b/src/or/or.h
index a382e9b32e..9d3fd976cb 100644
--- a/src/or/or.h
+++ b/src/or/or.h
@@ -838,12 +838,14 @@ typedef struct {
 
   struct config_line_t *ExitPolicy; /**< Lists of exit policy components. */
   struct config_line_t *SocksPolicy; /**< Lists of socks policy components */
+  /** Addresses to bind for listening for SOCKS connections. */
   struct config_line_t *SocksBindAddress;
-  /**< Addresses to bind for listening for SOCKS connections. */
+  /** Addresses to bind for listening for OR connections. */
   struct config_line_t *ORBindAddress;
-  /**< Addresses to bind for listening for OR connections. */
+  /** Addresses to bind for listening for directory connections. */
   struct config_line_t *DirBindAddress;
-  /**< Addresses to bind for listening for directory connections. */
+  /** Local address to bind outbound sockets */
+  char *OutboundBindAddress;
   char *RecommendedVersions; /**< Directory server only: which versions of
                               * Tor should we tell users to run? */
   char *User; /**< Name of user to run Tor as. */
@@ -1021,6 +1023,7 @@ struct config_line_t {
 };
 
 int config_assign_default_dirservers(void);
+int resolve_my_address(const char *address, uint32_t *addr);
 int getconfig(int argc, char **argv, or_options_t *options);
 int config_init_logs(or_options_t *options);
 void config_parse_exit_policy(struct config_line_t *cfg,
diff --git a/src/or/router.c b/src/or/router.c
index 972b8f8f19..440e404282 100644
--- a/src/or/router.c
+++ b/src/or/router.c
@@ -510,17 +510,20 @@ const char *router_get_my_descriptor(void) {
  */
 int router_rebuild_descriptor(void) {
   routerinfo_t *ri;
-  struct in_addr addr;
+  uint32_t addr;
   char platform[256];
-  if (!tor_inet_aton(options.Address, &addr)) {
-    log_fn(LOG_ERR, "options.Address didn't hold an IP.");
+  struct in_addr in;
+
+  if(resolve_my_address(options.Address, &addr) < 0) {
+    log_fn(LOG_WARN,"options.Address didn't resolve into an IP.");
     return -1;
   }
 
   ri = tor_malloc_zero(sizeof(routerinfo_t));
-  ri->address = tor_strdup(options.Address);
+  in.s_addr = htonl(addr);
+  ri->address = tor_strdup(inet_ntoa(in));
   ri->nickname = tor_strdup(options.Nickname);
-  ri->addr = (uint32_t) ntohl(addr.s_addr);
+  ri->addr = addr;
   ri->or_port = options.ORPort;
   ri->socks_port = options.SocksPort;
   ri->dir_port = options.DirPort;