Initial revision

svn:r2

1 files changed, 365 insertions, 0 deletions

diff --git a/src/or/routers.c b/src/or/routers.c
new file mode 100644
index 0000000000..d24d4d1bdb
--- /dev/null
+++ b/src/or/routers.c
@@ -0,0 +1,365 @@
+/**
+ * routers.c 
+ * Routines for loading the list of routers and their public RSA keys.
+ *
+ * Matej Pfajfar <mp292@cam.ac.uk>
+ */
+
+#define OR_ROUTERLIST_SEPCHARS " \t\n"
+#define OR_PUBLICKEY_BEGIN_TAG "-----BEGIN RSA PUBLIC KEY-----\n"
+
+#include "or.h"
+
+/* delete a list of routers from memory */
+void delete_routerlist(routerinfo_t *list)
+{
+  routerinfo_t *tmp = NULL;
+  
+  if (!list)
+    return;
+  
+  do
+  {
+    tmp=list->next;
+    free((void *)list->address);
+    RSA_free(list->pkey);
+    free((void *)list);
+    list = tmp;
+  }
+  while (list != NULL);
+  
+  return;
+}
+
+/* create an NULL-terminated array of pointers pointing to elements of a router list */
+/* this is done in two passes through the list - inefficient but irrelevant as this is
+ * only done once when op/or start up */
+routerinfo_t **make_rarray(routerinfo_t* list, size_t *len)
+{
+  routerinfo_t *tmp=NULL;
+  int listlen = 0;
+  routerinfo_t **array=NULL;
+  routerinfo_t **p=NULL;
+  
+  if ((!list) || (!len))
+    return NULL;
+  
+  /* get the length of the list */
+  tmp = list;
+  do
+  {
+    listlen++;
+    tmp = tmp->next;
+  }
+  while (tmp != NULL);
+  
+  array = malloc((listlen+1)*sizeof(routerinfo_t *));
+  if (!array)
+  {
+    log(LOG_ERR,"Error allocating memory.");
+    return NULL;
+  }
+  
+  tmp=list;
+  p = array;
+  do
+  {
+    *p = tmp;
+    p++;
+    tmp = tmp->next;
+  }
+  while(tmp != NULL);
+  *p=NULL;
+  
+  *len = listlen;
+  return array;
+}
+
+/* load the router list */
+routerinfo_t **getrouters(char *routerfile, size_t *lenp)
+{
+  int retval = 0;
+  char *retp = NULL;
+  routerinfo_t *router=NULL, *routerlist=NULL, *lastrouter=NULL;
+  FILE *rf; /* router file */
+  fpos_t fpos;
+  char line[512];
+  char *token;
+  char *errtest; /* detecting errors in strtoul() calls */
+  struct hostent *rent;
+
+  if ((!routerfile) || (!lenp))
+    return NULL;
+  
+  if (strcspn(routerfile,CONFIG_LEGAL_FILENAME_CHARACTERS) != 0)
+  {
+    log(LOG_ERR,"Filename %s contains illegal characters.",routerfile);
+    return NULL;
+  }
+  
+  /* open the router list */
+  rf = fopen(routerfile,"r");
+  if (!rf)
+  {
+    log(LOG_ERR,"Could not open %s.",routerfile);
+    return NULL;
+  }
+  
+  retp= fgets(line,512,rf);
+  while (retp)
+  {
+    log(LOG_DEBUG,"getrouters():Line :%s",line);
+    token = (char *)strtok(line,OR_ROUTERLIST_SEPCHARS);
+    if (token)
+    {
+      log(LOG_DEBUG,"getrouters():Token : %s",token);
+      if (token[0] != '#') /* ignore comment lines */
+      {
+	router = malloc(sizeof(routerinfo_t));
+	if (!router)
+	{
+	  log(LOG_ERR,"Could not allocate memory.");
+	  fclose(rf);
+	  delete_routerlist(routerlist);
+	  return NULL;
+	}
+	
+#if 0
+	router->conn_bufs = NULL; /* no output buffers */
+	router->last_conn_buf = NULL;
+	router->next_to_service = 0;
+	
+	router->s = -1; /* to signify this router is as yet unconnected */
+	router->celllen = 0; /* cell buffer is empty */
+#endif
+	
+	/* read the address */
+	router->address = malloc(strlen(token)+1);
+	if (!router->address)
+	{
+	  log(LOG_ERR,"Could not allocate memory.");
+	  fclose(rf);
+	  free((void *)router);
+	  delete_routerlist(routerlist);
+	  return NULL;
+	}
+	strcpy(router->address,token);
+	
+	rent = (struct hostent *)gethostbyname(router->address);
+	if (!rent)
+	{
+	  log(LOG_ERR,"Could not get address for router %s.",router->address);
+	  fclose(rf);
+	  free((void *)router->address);
+	  free((void *)router);
+	  delete_routerlist(routerlist);
+	  return NULL;
+	}
+
+	memcpy(&router->addr, rent->h_addr,rent->h_length);
+	
+	/* read the port */
+	token = (char *)strtok(NULL,OR_ROUTERLIST_SEPCHARS);
+	if (token)
+	{
+	  log(LOG_DEBUG,"getrouters():Token :%s",token);
+	  router->port = (uint16_t)strtoul(token,&errtest,0);
+	  if ((*token != '\0') && (*errtest == '\0')) /* conversion was successful */
+	  {
+	    /* convert port to network format */
+	    router->port = htons(router->port);
+	    
+	    /* read min bandwidth */
+	    token = (char *)strtok(NULL,OR_ROUTERLIST_SEPCHARS);
+	    if (token) /* min bandwidth */
+	    {
+	      router->min = (uint32_t)strtoul(token,&errtest,0);
+	      if ((*token != '\0') && (*errtest == '\0')) /* conversion was successful */
+	      {
+		if (router->min) /* must not be zero */
+		{
+		  /* read max bandwidth */
+		  token = (char *)strtok(NULL,OR_ROUTERLIST_SEPCHARS);
+		  if (token) /* max bandwidth */
+		  {
+		    router->max = (uint32_t)strtoul(token,&errtest,0);
+		    if ((*token != '\0') && (*errtest == '\0')) /* conversion was successful */
+		    {
+		      if (router->max) /* must not be zero */
+		      {
+			/* check that there is a public key entry for that router */
+			retval = fgetpos(rf, &fpos); /* save the current file position
+						      * we wil return to it later if we find a public key */
+			if (retval == -1)
+			{
+			  log(LOG_ERR,"Could not save position in %s.",routerfile);
+			  free((void *)router->address);
+			  free((void *)router);
+			  fclose(rf);
+			  delete_routerlist(routerlist);
+			  return NULL;
+			}
+			do /* read through to the next non-empty line */
+			{
+			  retp=fgets(line,512,rf);
+			  if (!retp)
+			  {
+			    log(LOG_ERR,"Could not find a public key entry for router %s:%u.",router->address,router->port);
+			    free((void *)router->address);
+			    free((void *)router);
+			    fclose(rf);
+			    delete_routerlist(routerlist);
+			    return NULL;
+			  }
+			  log(LOG_DEBUG,"getrouters():Line:%s",line);
+			  if ((*line != '#') && ( strspn(line,OR_ROUTERLIST_SEPCHARS) != strlen(line) ))
+			  {
+			    break;
+			  }
+			} while (1);
+			
+			if (!strcmp(line,OR_PUBLICKEY_BEGIN_TAG)) /* we've got the public key */
+			{
+			  retval = fsetpos(rf,&fpos); /* get us back to where we were otherwise crypto lib won't find the key */
+			  if (retval == -1)
+			  {
+			    log(LOG_ERR,"Could not set position in %s.",routerfile);
+			    free((void *)router->address);
+			    free((void *)router);
+			    fclose(rf);
+			    delete_routerlist(routerlist);
+			    return NULL;
+			  }
+			}
+			else /* we found something else; this isn't right */
+			{
+			  log(LOG_ERR,"Could not find a public key entry for router %s:%u.",router->address,router->port);
+			  free((void *)router->address);
+			  free((void *)router);
+			  fclose(rf);
+			  delete_routerlist(routerlist);
+			  return NULL;
+			}
+			
+			log(LOG_DEBUG,"getrouters():Reading the key ...");
+			/* read the public key into router->pkey */
+			router->pkey=NULL;
+			router->pkey = PEM_read_RSAPublicKey(rf,&router->pkey,NULL,NULL);
+			if (!router->pkey) /* something went wrong */
+			{
+			  log(LOG_ERR,"Could not read public key for router %s:%u.",router->address,router->port);
+			  free((void *)router->address);
+			  free((void *)router);
+			  fclose(rf);
+			  delete_routerlist(routerlist);
+			  return NULL;
+			}
+			else /* read the key */
+			{
+			  log(LOG_DEBUG,"getrouters():Public key size = %u.", RSA_size(router->pkey));
+			  if (RSA_size(router->pkey) != 128) /* keys MUST be 1024 bits in size */
+			  {
+			    log(LOG_ERR,"Key for router %s:%u is not 1024 bits. All keys must be exactly 1024 bits long.",router->address,router->port);
+			    free((void *)router->address);
+			    RSA_free(router->pkey);
+			    free((void *)router);
+			    fclose(rf);
+			    delete_routerlist(routerlist);
+			    return NULL;
+			  }
+			  router->next = NULL;
+			  /* save the entry into the routerlist linked list */
+			  if (!routerlist) /* this is the first entry */
+			    routerlist = router;
+			  else
+			    lastrouter->next = (void *)router;
+			  lastrouter = router;
+			}
+		      }
+		      else /* maximum link utilisation is zero */
+		      {
+			log(LOG_ERR,"Entry for router %s doesn't contain a valid maximum bandwidth entry (must be > 0).",router->address);
+			free((void *)router->address);
+			free((void *)router);
+			fclose(rf);
+			delete_routerlist(routerlist);
+			return NULL;
+		      }
+		    }
+		    else
+		    {
+		      log(LOG_ERR,"Entry for router %s doesn't seem to contain a valid maximum bandwidth entry.",router->address);
+		      free((void *)router->address);
+		      free((void *)router);
+		      fclose(rf);
+		      delete_routerlist(routerlist);
+		      return NULL;
+		    }
+		  }
+		  else
+		  {
+		    log(LOG_ERR,"Entry for router %s doesn't seem to contain a maximum bandwidth entry.",router->address);
+		    free((void *)router->address);
+		    free((void *)router);
+		    fclose(rf);
+		    delete_routerlist(routerlist);
+		    return NULL;
+		  }
+		}
+		else
+		{
+		  log(LOG_ERR,"Entry for router %s doesn't contain a valid minimum bandwidth entry (must be > 0).",router->address);
+		  free((void *)router->address);
+		  free((void *)router);
+		  fclose(rf);
+		  delete_routerlist(routerlist);
+		  return NULL;
+		}
+	      }
+	      else
+	      {
+		log(LOG_ERR,"Entry for router %s doesn't seem to contain a valid minimum bandwidth entry.",router->address);
+		free((void *)router->address);
+		free((void *)router);
+		fclose(rf);
+		delete_routerlist(routerlist);
+		return NULL;
+	      }
+	    }
+	    else
+	    {
+	      log(LOG_ERR,"Entry for router %s doesn't seem to contain a minimum bandwidth entry.",router->address);
+	      free((void *)router->address);
+	      free((void *)router);
+	      fclose(rf);
+	      delete_routerlist(routerlist);
+	      return NULL;
+	    }
+	  }
+	  else
+	  {
+	    log(LOG_ERR,"Entry for router %s doesn't seem to contain a valid port number.",router->address);
+	    free((void *)router->address);
+	    free((void *)router);
+	    fclose(rf);
+	    delete_routerlist(routerlist);
+	    return NULL;
+	  }
+	}
+	else
+	{
+	  log(LOG_ERR,"Entry for router %s doesn't seem to contain a port number.",router->address);
+	  free((void *)router->address);
+	  free((void *)router);
+	  fclose(rf);
+	  delete_routerlist(routerlist);
+	  return NULL;
+	}
+      }
+    }
+    retp=fgets(line,512,rf);
+  }
+  
+  fclose(rf);
+  return make_rarray(routerlist, lenp);
+}