package main import ( "fmt" "math/rand" "strings" "time" r2pipe "github.com/radare/r2pipe-go" "github.com/sirupsen/logrus" ) func buildBots(config *Config) { logrus.Info("Building all bots") // build all the bots for i := 0; i < config.AmountOfBots; i++ { buildBot(i, config) } } // buildBot builds the bot located at the given path. func buildBot(i int, config *Config) { logrus.Debugf("Building bot %d", i) // open radare without input for building the bot r2p1, err := r2pipe.NewPipe("--") if err != nil { panic(err) } defer r2p1.Close() // Compile a warrior using rasm2 // // This uses the given architecture, the given bitness and the given path in // rasm2 to compile the bot botPath := config.Bots[i].Path radareCommand := fmt.Sprintf("rasm2 -a %s -b %d -f %s", config.Arch, config.Bits, botPath) botSource := r2cmd(r2p1, radareCommand) config.Bots[i].Source = botSource } // init initializes the arena func initArena(config *Config) *r2pipe.Pipe { logrus.Info("Initializing the arena") logrus.Debugf("Allocating %d bytes of memory...", config.Memsize) // allocate memory r2p, err := r2pipe.NewPipe(fmt.Sprintf("malloc://%d", config.Memsize)) if err != nil { panic(err) } logrus.Info("Memoy successfully allocated") // define the architecture and the bitness _ = r2cmd(r2p, fmt.Sprintf("e asm.arch = %s", config.Arch)) _ = r2cmd(r2p, fmt.Sprintf("e asm.bits = %d", config.Bits)) // enable colors // _ = r2cmd(r2p, "e scr.color = 0") _ = r2cmd(r2p, "e scr.color = 3") _ = r2cmd(r2p, "e scr.color.args = true") _ = r2cmd(r2p, "e scr.color.bytes = true") _ = r2cmd(r2p, "e scr.color.grep = true") _ = r2cmd(r2p, "e scr.color.ops = true") _ = r2cmd(r2p, "e scr.bgfill = true") _ = r2cmd(r2p, "e scr.color.pipe = true") _ = r2cmd(r2p, "e scr.utf8 = true") // hex column width _ = r2cmd(r2p, "e hex.cols = 32") // initialize ESIL VM state logrus.Debug("Initializing the ESIL VM") _ = r2cmd(r2p, "aei") // initialize ESIL VM stack logrus.Debug("Initializing the ESIL Stack") _ = r2cmd(r2p, "aeim") // return the pipe return r2p } // genRandomOffsets returns random offsets for all bots // This is used to get the offset the bots are initially placed in func genRandomOffsets(config *Config) { logrus.Info("Generating random bot offsets") // define the amount of bots, an array to store the offsets in and a counter // to store the amount of tries it took to find a random positon for the bots var amountOfBots int = len(config.Bots) var offsets []int var roundCounter int = 0 // seed the random number generator rand.Seed(time.Now().UTC().UnixNano()) for { // reset the offsets array offsets = []int{} // define a random address // | ------------------------------------- | ----- | // | generate an address in this space address := rand.Intn(config.Memsize - config.MaxProgSize) logrus.Tracef("%d", address) // for all bots, try to generate another random address after the intially // generated address and test if it fits in memory for i := 0; i < amountOfBots; i++ { // append the address to the offsets array offsets = append(offsets, address) // define a min and max bound // // | ------|-|----------------------------------|-| // | | | in this space | | // a b c d e // // a = 0x0 // b = address // c = address + config.MaxProcSize (min) // d = config.Memsize - config.MaxProgSize (max) // e = config.Memsize min := address + config.MaxProgSize max := config.Memsize - config.MaxProgSize // if the new minimum bound is bigger or equal to the maximum bound, // discard this try and start with a fresh new initial address if min >= max { roundCounter++ break } // generate a new address in the [min, max) range defined above address = rand.Intn(max-min) + min logrus.Tracef("%d", address) // If there isn't enough space inbetween the address and the biggest // possible address, as in, the biggest possible bot can't fit in that // space, discard and start with a new fresh initial address if (config.Memsize-config.MaxProgSize)-address < config.MaxProgSize { roundCounter++ break } } // if the needed amount of offsets has been found, break out of the infinite loop if len(offsets) == amountOfBots { break } } logrus.Infof("Initial bot positions found after %d tries", roundCounter) // debug print all offsets var fields0 logrus.Fields = make(logrus.Fields) for i := 0; i < len(offsets); i++ { fields0[fmt.Sprintf("%d", i)] = offsets[i] } logrus.WithFields(fields0).Debug("Offsets") // shuffle the offsets rand.Shuffle(len(offsets), func(i, j int) { offsets[i], offsets[j] = offsets[j], offsets[i] }) // debug print the shuffled offsets var fields1 logrus.Fields = make(logrus.Fields) for i := 0; i < len(offsets); i++ { fields1[fmt.Sprintf("%d", i)] = offsets[i] } logrus.WithFields(fields1).Debug("Shuffled offsets") config.RandomOffsets = offsets } // place the bot in the arena at the given address func placeBot(r2p *r2pipe.Pipe, bot Bot, address int) { _ = r2cmd(r2p, fmt.Sprintf("wx %s @ %d", bot, address)) }