diff options
| -rw-r--r-- | src/org/noreply/fancydress/type3/PathSpec.java | 115 |
1 files changed, 51 insertions, 64 deletions
diff --git a/src/org/noreply/fancydress/type3/PathSpec.java b/src/org/noreply/fancydress/type3/PathSpec.java index 07c24da..9c83679 100644 --- a/src/org/noreply/fancydress/type3/PathSpec.java +++ b/src/org/noreply/fancydress/type3/PathSpec.java @@ -209,61 +209,54 @@ public class PathSpec { } /** - * A class holding a list of Servers and a Crossover point location. + * make a Path from a serverlist an a crossover point. + * + * @param servers a list of servers, for null elements a random recommended server is chosen + * @param crossoverPoint place the crossover point before this server. + * + * @throws Mix3PathProblemException if no useable random servers can be found */ - private class ServerlistWithCrossover { - public Server[] servers; - public int crossoverPoint; - - public ServerlistWithCrossover(Server[] servers, int crossoverPoint) { - this.servers = servers; - this.crossoverPoint = crossoverPoint; - } - - private void fillInRandoms() throws Mix3PathProblemException { - Server[] recommended = dir.getRecommendedServers(); - for (int i=servers.length-1; i>=0 ; i--) { - if (servers[i] != null) - continue; - ArrayList s = new ArrayList(); - for (int r=0; r<recommended.length; r++) - if ( - /* last hop or */ - ((i == servers.length-1) || ( - /* next hop is different */ - (recommended[r] != servers[i+1]) && - /* and can talk to next hop */ - dir.areFriends(recommended[r], servers[i+1]) )) && - /* first hop, or previos hop is random, or */ - ((i == 0) || (servers[i-1] == null) || ( - /* previous hop is different */ - (recommended[r] != servers[i-1]) && - /* and prev hop can talk to this */ - dir.areFriends(servers[i-1], recommended[r]) )) - ) - s.add(recommended[r]); - if (s.size() == 0) - throw new Mix3PathProblemException("Cannot find useable servers for random hop."); - servers[i] = (Server) s.get(CryptoPrimitives.randInt(s.size())); - } + private Path makePathFromServerlist(Server[] servers, int crossoverPoint) throws Mix3PathProblemException { + /* Fill in randoms */ + Server[] recommended = dir.getRecommendedServers(); + for (int i=servers.length-1; i>=0 ; i--) { + if (servers[i] != null) + continue; + ArrayList s = new ArrayList(); + for (int r=0; r<recommended.length; r++) + if ( + /* last hop or */ + ((i == servers.length-1) || ( + /* next hop is different */ + (recommended[r] != servers[i+1]) && + /* and can talk to next hop */ + dir.areFriends(recommended[r], servers[i+1]) )) && + /* first hop, or previos hop is random, or */ + ((i == 0) || (servers[i-1] == null) || ( + /* previous hop is different */ + (recommended[r] != servers[i-1]) && + /* and prev hop can talk to this */ + dir.areFriends(servers[i-1], recommended[r]) )) + ) + s.add(recommended[r]); + if (s.size() == 0) + throw new Mix3PathProblemException("Cannot find useable servers for random hop."); + servers[i] = (Server) s.get(CryptoPrimitives.randInt(s.size())); } - public Path getPath() throws Mix3PathProblemException { - fillInRandoms(); - Hop[] hops = new Hop[servers.length]; - for (int i=0; i<hops.length ; i++) - hops[i] = new Hop(servers[i]); - - if (crossoverPoint == -1) - crossoverPoint = (hops.length+1)/2; - int len1 = crossoverPoint; - int len2 = hops.length - len1; - Hop[] l1 = new Hop[len1]; - Hop[] l2 = new Hop[len2]; - System.arraycopy(hops, 0, l1, 0, len1); - System.arraycopy(hops, len1, l2, 0, len2); - return new Path(l1, l2); - } + Hop[] hops = new Hop[servers.length]; + for (int i=0; i<hops.length ; i++) + hops[i] = new Hop(servers[i]); + + if (crossoverPoint == -1) + crossoverPoint = (hops.length+1)/2; + int len1 = crossoverPoint; + int len2 = hops.length - len1; + Hop[] l1 = new Hop[len1]; + Hop[] l2 = new Hop[len2]; + System.arraycopy(hops, 0, l1, 0, len1); + System.arraycopy(hops, len1, l2, 0, len2); + return new Path(l1, l2); } /** @@ -273,8 +266,9 @@ public class PathSpec { * for client site fragmentation assembly). If none * was chosen, pass null. * @return a list of servers and a crossover point as an ServerlistWithCrossover object. + * @throws Mix3PathProblemException if no useable random servers can be found */ - private ServerlistWithCrossover concatComponents(Server exitHop) throws Mix3PathProblemException { + private Path concatComponents(Server exitHop) throws Mix3PathProblemException { Server[][] components = new Server[pathComponents.length][]; int length = 0; int crossoverBefore = -1; @@ -300,7 +294,7 @@ public class PathSpec { if (exitHop != null) servers[servers.length-1] = exitHop; - ServerlistWithCrossover result = new ServerlistWithCrossover(servers, crossoverBefore); + Path result = makePathFromServerlist(servers, crossoverBefore); return result; } @@ -344,16 +338,9 @@ public class PathSpec { exitHop = recommendedExitHops[ CryptoPrimitives.randInt(recommendedExitHops.length) ]; - ServerlistWithCrossover[] serverlists = new ServerlistWithCrossover[payload.numPackets()]; - for (int i=0; i<serverlists.length; i++) { - serverlists[i] = concatComponents( exitHop ); - if (serverlists[i].servers.length < 2) - throw new Mix3PathProblemException("Path too short."); - } - - Path[] result = new Path[serverlists.length]; - for (int i=0; i<serverlists.length; i++) - result[i] = serverlists[i].getPath(); + Path[] result = new Path[payload.numPackets()]; + for (int i=0; i<result.length; i++) + result[i] = concatComponents( exitHop ); return result; } |