Initial import : make-boot-image.sh operationnal. Dumb mcastseed.

5 files changed, 1105 insertions, 0 deletions

diff --git a/mcastseed/src/Makefile.am b/mcastseed/src/Makefile.am
new file mode 100644
index 0000000..b28166c
--- /dev/null
+++ b/mcastseed/src/Makefile.am
@@ -0,0 +1,12 @@
+## Process this file with automake to produce Makefile.in
+
+AM_CFLAGS =\
+	 -Wall \
+	 -g
+
+bin_PROGRAMS = mcastseed mcastleech
+
+mcastseed_SOURCES = mcastseed.c msock.c
+mcastleech_SOURCES = mcastleech.c msock.c
+
+LDADD = @WSOCKLIB@
diff --git a/mcastseed/src/mcastleech.c b/mcastseed/src/mcastleech.c
new file mode 100644
index 0000000..d19bff9
--- /dev/null
+++ b/mcastseed/src/mcastleech.c
@@ -0,0 +1,227 @@
+/* client.c
+ * Greatly inspired from examples written by tmouse, July 2005
+ * http://cboard.cprogramming.com/showthread.php?t=67469
+ * Modified to run multi-platform by Christian Beier <dontmind@freeshell.org>.
+ */
+
+#ifndef __MINGW32__
+#include <unistd.h>
+#endif
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include "msock.h" 
+
+#define MULTICAST_RECV_BUF 10240
+#define MULTICAST_SO_RCVBUF 425984
+#define DEFAULT_MCAST_IP_STR "ff02::114"
+#define DEFAULT_PORT_STR "9000"
+
+/* Cmdline Arguments */
+char *prog_name = NULL;
+char *mcast_ip = NULL; 
+char *port = NULL;
+
+/* Sockets as global, used everywhere, even in die() */
+SOCKET mcast_sock = (SOCKET) -1; /* Multicast socket for receiving data */
+SOCKET ucast_sock = (SOCKET) -1; /* Unicast socket for give feedback to server */
+
+/* Buffer used for earch recvfrom() */
+char recvbuf[MULTICAST_RECV_BUF];
+
+/* Strings to print out representation of various states of the program */
+const char * const state_str[] = {
+	"exiting",
+	"wait_hello_and_connect_back",
+	"wait_start_and_start_job",
+	"receive_data",
+	"finalize_job",
+	"is_there_more_job"
+};
+
+/* Some boring funcs you didn't want to read now */
+void die(char* msg);
+void usage(char *msg);
+void arg_parse(int argc, char* argv[]);
+
+/* Parts of the "protocol", definitions are after main() */
+int wait_hello_and_connect_back();
+int wait_start_and_start_job();
+int receive_data();
+int finalize_job();
+int is_there_more_job();
+
+
+int main(int argc, char* argv[]) {
+	int state = 1; /* state of the "protocol" state machine */
+	int res;
+
+	arg_parse(argc, argv);
+
+	/* Finite state machine */
+	while ( state > 0 ) {
+		fprintf(stderr, "Now in %s state\n", state_str[state]);
+		switch ( state ) {
+			case 1: state = (wait_hello_and_connect_back() == 0)?2:1; break;
+			case 2: state = (wait_start_and_start_job() == 0)?2:3; break;
+			case 3: res = receive_data();
+							if (res==0) state = 4;
+							else if (res==1) state=3;
+							else state = -1;
+							break;
+			case 4: state = (finalize_job() == 0)?5:-2; break;
+			case 5: state = (is_there_more_job() == 0)?2:0; break;
+		}
+	}
+
+	if ( mcast_sock > 0 ) {
+		close(mcast_sock);
+	}
+
+	if ( state < 0 )
+		return -state;
+
+	return EXIT_SUCCESS;
+}
+
+
+int wait_hello_and_connect_back() {
+	/* Buffers for host and service strings after resolve */
+	char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV];
+	/* Server address, filled by system after first recvfrom */
+	struct sockaddr_storage peer_addr;
+	socklen_t peer_addr_len;
+	/* Various needed variables */
+	ssize_t nread;
+	int res;
+
+	/* Setup mcast_sock */
+	if ( mcast_sock > 0 ) {
+		close(mcast_sock);
+		mcast_sock = 0;
+	}
+	mcast_sock = mcast_recv_socket(mcast_ip, port, MULTICAST_SO_RCVBUF);
+	if(mcast_sock < 0)
+			usage("Could not setup multicast socket. Wrong args given ?");
+
+	/* Wait for a single datagram from the server (for sync, no check on contain) */
+	peer_addr_len = sizeof(struct sockaddr_storage);
+	nread = recvfrom(mcast_sock, recvbuf, MULTICAST_RECV_BUF, 0, (struct sockaddr *) &peer_addr, &peer_addr_len);
+ 	if (nread < 0 ) {	
+		perror("recvfrom() failed");
+		return -1;	
+	}
+	/* Get peer informations as strings from peer_addr */
+	res = getnameinfo((struct sockaddr *) &peer_addr, peer_addr_len,
+			 hbuf, NI_MAXHOST, sbuf, NI_MAXSERV, NI_NUMERICSERV);
+	if ( res != 0 ) {
+		fprintf(stderr, "getnameinfo: %s\n", gai_strerror(res));
+		return -2;	
+	}
+	/* Connect back to the server, with reliable unicast */
+	if ( ucast_sock > 0 ) {
+		close(ucast_sock);
+	}
+	ucast_sock = ucast_client_socket(hbuf,port);
+	if(ucast_sock < 0) {
+		fprintf(stderr, "Could not setup unicast socket or connect to %s:%s\n", hbuf, port);
+		return -3;	
+	}
+
+	return 0;
+}
+
+int wait_start_and_start_job() {
+	ssize_t nread, nwrite;
+
+	/* Wait for a "start" datagram from the server */
+	nread = recvfrom(mcast_sock, recvbuf, MULTICAST_RECV_BUF, 0, NULL, 0);
+ 	if (nread < 0 ) {	
+		perror("recvfrom() failed");
+		return -1;	
+	}
+	if ( nread >= 5 && strncmp("start", recvbuf, 5) == 0 ) {
+
+		nwrite = write(ucast_sock, "ready", 5);
+		if ( nwrite < 0 ) {
+			fprintf(stderr, "write() failed\n");
+			return -2;
+		}
+		if (nwrite != 5) {
+			fprintf(stderr, "write() short\n");
+			return -3;
+		}
+
+		return 1;
+	}
+
+	return 0;	
+}
+
+int receive_data() {
+	ssize_t nread;
+	uint32_t seq;
+	uint16_t datalen;
+
+	/* Wait for a "dataN" datagram from the server */
+	nread = recvfrom(mcast_sock, recvbuf, MULTICAST_RECV_BUF, 0, NULL, 0);
+ 	if (nread < 0 ) {	
+		perror("recvfrom() failed");
+		return -1;	
+	}
+	if ( nread >= 10 && strncmp("data", recvbuf, 4) == 0 ) {
+		seq = ntohl( *( (uint32_t *) recvbuf+1 ) );
+		datalen = ntohs( *( (uint16_t *) recvbuf+4 ) );
+		//fprintf(stderr, "debug seq==%i, datalen==%hi\n", seq, datalen);
+		if ( nread != (10 + datalen) ) {
+			fprintf(stderr, "debug nread==%zi, (10 + datalen)==%i\n", nread, (10 + datalen));
+			//TODO nack ?
+			return -2;
+		}
+		fprintf(stdout, "data #%i, ", seq);
+		fwrite(recvbuf+10, datalen, 1, stdout);
+		fflush(stdout);
+		//TODO buffer zero copy, ack
+		return 1;
+	}
+
+	return 0;
+}
+
+int finalize_job() {
+	return 0;	
+}
+int is_there_more_job() {
+	return 1;
+}
+
+
+
+
+void die(char* msg) {
+	fprintf(stderr, "%s\n", msg);
+	if (mcast_sock > 0)
+		close(mcast_sock);
+	if (ucast_sock > 0)
+		close(ucast_sock);
+	exit(EXIT_FAILURE);
+}
+
+void usage(char *msg) {
+	char ubuf[256];
+	if ( msg != NULL )
+		fprintf(stderr, "%s\n", msg);
+	ubuf[0] = '\0';
+	snprintf(ubuf, 255, "Usage: %s [port] [mcast_ip]\n", prog_name);
+	die(ubuf);
+}
+
+void arg_parse(int argc, char* argv[]) {
+	prog_name = argv[0];
+	if ( argc > 3 )
+		usage("Too many arguments");	
+	port = (argc >= 2)?argv[1]:DEFAULT_PORT_STR;
+	mcast_ip = (argc >= 3)?argv[2]:DEFAULT_MCAST_IP_STR;
+}
+
diff --git a/mcastseed/src/mcastseed.c b/mcastseed/src/mcastseed.c
new file mode 100644
index 0000000..da73353
--- /dev/null
+++ b/mcastseed/src/mcastseed.c
@@ -0,0 +1,421 @@
+/* server.c
+ * Greatly inspired from examples written by tmouse, July 2005
+ * http://cboard.cprogramming.com/showthread.php?t=67469
+ * Modified to run multi-platform by Christian Beier <dontmind@freeshell.org>.
+ */
+
+#ifndef __MINGW32__
+#include <unistd.h> /* for usleep() */
+#endif
+#include <stdio.h>
+#include <stdlib.h>
+#include "msock.h"
+
+#define READ_BUF_LEN 256
+#define MAX_PENDING_CONNECTIONS 256
+#define MAX_CLIENTS 256
+#define DEFAULT_MCAST_IP_STR "ff02::114"
+#define DEFAULT_PORT_STR "9000"
+#define DEFAULT_MCAST_TTL 1
+
+/* Cmdline Arguments */
+char *prog_name = NULL;
+char *mcast_ip = NULL; 
+char *port = NULL;
+int mcast_ttl = 0;
+
+/* Sockets as global, used everywhere, even in die() */
+SOCKET mcast_sock = (SOCKET) -1; /* Multicast socket for sending data */
+SOCKET ucast_sock = (SOCKET) -1; /* Unicast socket for havee feedback from clients */
+
+/* Socket related data */
+struct addrinfo *mcast_addr = NULL;
+struct client {
+	SOCKET sock;
+	struct sockaddr addr;
+	int state;
+} clients[MAX_CLIENTS];
+int clients_next = 0;
+
+/* Buffer used for earch read() */
+char readbuf[READ_BUF_LEN];
+
+/* Strings to print out representation of various states of the program */
+const char * const state_str[] = {
+	"exiting",
+	"send_hello",
+	"accept_pending_clients_or_wait_a_bit",
+	"start_job",
+	"send_data",
+	"wait_all_finalize_job",
+	"is_there_more_job"
+};
+
+/* Some boring funcs you didn't want to read now */
+void die(char* msg);
+void usage(char *msg);
+void arg_parse(int argc, char* argv[]);
+void unsetup_sockets();
+void setup_sockets();
+
+/* Parts of the "protocol", definitions are after main() */
+int send_hello();
+int accept_pending_clients_or_wait_a_bit();
+int start_job();
+int send_data();
+int wait_all_finalize_job();
+int is_there_more_job();
+
+int main(int argc, char *argv[]) {
+	int state = 1; /* state of the "protocol" state machine */
+	int res;
+	arg_parse(argc, argv);
+	setup_sockets();
+
+	/* Finite state machine */
+	while ( state > 0 ) {
+		fprintf(stderr, "Now in %s state\n", state_str[state]);
+		switch ( state ) {
+			case 1: res = send_hello(); state = (res==0)?2:-1; break;
+			case 2: res = accept_pending_clients_or_wait_a_bit();
+							if (res==0) state = 2; // Some clients has just come in, try to get more
+							else if	(res==1) state = 1; // Nothing new. Keep accepting clients after another hello
+							else if (res==2) state = 3; // Wanted clients are accepted
+							else state = -2;
+							break;
+			case 3: res = start_job();
+							if (res==0) state = 3; // Keep trying to convince every client to start
+							else if (res==1) state = 4; // All clients have started the job pipe
+							else if	(res==2) state = 4; // There is dead clients but all alive are ready to go
+							else state = -3;
+							break;
+			case 4: res = send_data();
+							if (res==0) state = 4;
+							else if (res==1) state = 5; // All data sent
+							else state = -4;
+							break;
+			case 5: res = wait_all_finalize_job();
+							if (res==0) state = 5;
+							else if (res==1) state = 6;
+							else state = -5;
+			case 6: res = is_there_more_job();
+							if (res==0) state = 0;
+							else if (res==1) state = 3;
+							else state = -6;
+							break;
+		}
+	}
+
+	unsetup_sockets();
+
+	if ( state < 0 )
+	  return -state;
+
+	return EXIT_SUCCESS;
+}
+
+int send_hello() {
+	ssize_t nwrite;
+	const char *payload = "hello";
+	int paylen = strlen(payload);
+
+	nwrite = sendto(mcast_sock, payload, paylen, 0, mcast_addr->ai_addr, mcast_addr->ai_addrlen);
+	if ( nwrite < 0 ) {
+		perror("sendto() failed");
+		return -1;
+	}
+	if ( nwrite < paylen ) {
+		fprintf(stderr, "%s", "Short packet sent");
+	}
+
+	return 0;
+}
+
+int accept_pending_clients_or_wait_a_bit() {
+	struct timeval timeout;
+	fd_set readfds, exceptfds;
+	ssize_t nread;
+	int res;
+
+	FD_ZERO(&readfds);
+	FD_ZERO(&exceptfds);
+	FD_SET(0,&readfds); // Read from stdin. Will never work as is on Windows, requires threads and so.
+	FD_SET(ucast_sock,&readfds);
+	FD_SET(ucast_sock,&exceptfds);
+	timeout.tv_sec = 2;
+	timeout.tv_usec = 0;
+
+	res = select(ucast_sock+1, &readfds, NULL, &exceptfds, &timeout);
+	if ( res < 0 ) {
+		perror("select() failed");
+		return -1;
+	}
+
+	if ( res > 0 ) {
+		if (FD_ISSET(ucast_sock, &readfds)) {
+			//TODO : this assumes that the event is an accept() while ones could be send data there
+			if ( clients_next >= MAX_CLIENTS ) {
+				fprintf(stderr, "%s\n", "Bouncing client, MAX_CLIENTS reached");
+				close(accept(ucast_sock, NULL, 0));
+			} else {
+				socklen_t addrlen = sizeof(struct sockaddr);
+				clients[clients_next].sock = accept(ucast_sock, &(clients[clients_next].addr), &addrlen);
+				clients[clients_next].state = 0;
+				printf("Connected client on fd %i\n", clients[clients_next].sock);
+				clients_next++;
+			}
+		}
+		//TODO : drop this keybord read with accept(), this is not portable
+		if ( FD_ISSET(0, &readfds)) {
+			nread = read(0, readbuf, READ_BUF_LEN);
+			if ( nread <= 0 ) {
+				fprintf(stderr, "%s\n", "lost stdin");
+			}
+			// User wants to go now
+			return 2;
+		}
+		if (FD_ISSET(ucast_sock, &exceptfds)) {
+			fprintf(stderr, "%s\n", "unhandled except on ucast_sock");
+			return -2;
+		}
+	}
+	if (res == 0 ) {
+		// nothing happened before timeout
+		return 1;
+	}
+	return 0;
+}
+
+int start_job() {
+	struct timeval timeout;
+	fd_set readfds, exceptfds;
+	ssize_t nread, nwrite;
+	int all_ready, all_non_dead_ready;
+	int i, res;
+	SOCKET client_sock;
+	const char *payload = "start";
+	int paylen = strlen(payload);
+
+	nwrite = sendto(mcast_sock, payload, paylen, 0, mcast_addr->ai_addr, mcast_addr->ai_addrlen);
+	if ( nwrite < 0 ) {
+		perror("sendto() failed");
+		return -1;
+	}
+	if ( nwrite < paylen ) {
+		fprintf(stderr, "%s", "Short packet sent");
+	}
+
+	all_ready = 1;
+	all_non_dead_ready = 1;
+
+	FD_ZERO(&readfds);
+	FD_ZERO(&exceptfds);
+	for ( i=0; i<clients_next; i++) {
+		FD_SET(clients[i].sock,&readfds);
+		FD_SET(clients[i].sock,&exceptfds);
+	}
+	timeout.tv_sec = 2;
+	timeout.tv_usec = 0;
+	res = select(clients_next, &readfds, NULL, &exceptfds, &timeout);
+	if ( res < 0 ) {
+		perror("select() failed");
+		return -1;
+	}
+
+	if ( res > 0 ) {
+		for ( i=0; i<clients_next; i++) {
+			client_sock = clients[i].sock;
+			if (FD_ISSET(client_sock, &readfds)) {
+				printf("todo info from client %i\n", i);
+				nread = read(client_sock, readbuf, 5);
+				if ( nread <= 0 ) {
+					fprintf(stderr, "lost client %i\n", i);
+					clients[i].state = 2;
+				} else if ( nread < 5 ) {
+					fprintf(stderr, "short data from %i\n", i);
+					clients[i].state = 2;
+				} else if ( strncmp("ready", readbuf, 5) != 0 ) {
+					fprintf(stderr, "unexpected data from %i\n", i);
+					clients[i].state = 2;
+				} else {
+					// Received "ready" ack from client
+					clients[i].state = 1;
+				}
+			}
+			if (FD_ISSET(clients[i].sock, &exceptfds)) {
+				fprintf(stderr, "unhandled except on client %i\n", i);
+					clients[i].state = 2;
+			}
+			all_ready &= (clients[i].state == 1);
+			if ( clients[i].state != 2)
+				all_non_dead_ready &= (clients[i].state == 1);
+		}
+	}
+	// (res == 0 ) nothing happened before timeout
+
+	if ( all_ready )
+		return 1;
+	if ( all_non_dead_ready )
+		return 2;
+
+	return 0;
+}
+
+
+int send_data() {
+	ssize_t nwrite;
+	char buf[] = "dataXXXXXXJe suis à la plage.";
+	int paylen = strlen(buf)-10;
+	int seq = 1;
+
+	//FIXME use http://troydhanson.github.io/tpl/index.html
+	*( (uint32_t *) buf+1 ) = htonl(seq);
+	*( (uint16_t *) buf+4 ) = htons(paylen);
+
+	nwrite = sendto(mcast_sock, buf, 10+paylen, 0, mcast_addr->ai_addr, mcast_addr->ai_addrlen);
+	if ( nwrite < 0 ) {
+		perror("sendto() failed");
+		return -1;
+	}
+	if ( nwrite < paylen ) {
+		fprintf(stderr, "%s", "Short packet sent");
+	}
+
+	return 1;	
+}
+
+
+int wait_all_finalize_job() {
+	struct timeval timeout;
+	fd_set readfds, exceptfds;
+	ssize_t nread, nwrite;
+	int all_non_dead_done;
+	int i, res;
+	SOCKET client_sock;
+	const char *payload = "final";
+	int paylen = strlen(payload);
+
+	nwrite = sendto(mcast_sock, payload, paylen, 0, mcast_addr->ai_addr, mcast_addr->ai_addrlen);
+	if ( nwrite < 0 ) {
+		perror("sendto() failed");
+		return -1;
+	}
+	if ( nwrite < paylen ) {
+		fprintf(stderr, "%s", "Short packet sent");
+	}
+
+	all_non_dead_done = 1;
+
+	FD_ZERO(&readfds);
+	FD_ZERO(&exceptfds);
+	for ( i=0; i<clients_next; i++) {
+		FD_SET(clients[i].sock,&readfds);
+		FD_SET(clients[i].sock,&exceptfds);
+	}
+	timeout.tv_sec = 2;
+	timeout.tv_usec = 0;
+	res = select(clients_next, &readfds, NULL, &exceptfds, &timeout);
+	if ( res < 0 ) {
+		perror("select() failed");
+		return -1;
+	}
+
+	if ( res > 0 ) {
+		for ( i=0; i<clients_next; i++) {
+			client_sock = clients[i].sock;
+			if (FD_ISSET(client_sock, &readfds)) {
+				printf("todo info from client %i\n", i);
+				nread = read(client_sock, readbuf, 5);
+				if ( nread <= 0 ) {
+					fprintf(stderr, "lost client %i\n", i);
+					clients[i].state = 2;
+				} else if ( nread < 5 ) {
+					fprintf(stderr, "short data from %i\n", i);
+					clients[i].state = 2;
+				} else if ( strncmp("done.", readbuf, 5) != 0 ) {
+					fprintf(stderr, "unexpected data from %i\n", i);
+					clients[i].state = 2;
+				} else {
+					// Received "done." ack from client
+					clients[i].state = 3;
+				}
+			}
+			if (FD_ISSET(clients[i].sock, &exceptfds)) {
+				fprintf(stderr, "unhandled except on client %i\n", i);
+					clients[i].state = 2;
+			}
+			if ( clients[i].state != 2)
+				all_non_dead_done &= (clients[i].state == 3);
+		}
+	}
+	// (res == 0 ) nothing happened before timeout
+
+	if ( all_non_dead_done )
+		return 1;
+
+	return 0;
+}
+
+
+int is_there_more_job() {
+	return 0;
+}
+
+
+void die(char* msg) {
+	fprintf(stderr, "%s\n", msg);
+	if (mcast_sock > 0)
+		close(mcast_sock);
+	if (ucast_sock > 0)
+		close(ucast_sock);
+	exit(EXIT_FAILURE);
+}
+
+void usage(char *msg) {
+	char ubuf[256];
+	if ( msg != NULL )
+		fprintf(stderr, "%s\n", msg);
+	ubuf[0] = '\0';
+	snprintf(ubuf, 255, "Usage: %s [port] [mcast_ip] [mcast_ttl]\n", prog_name);
+	die(ubuf);
+}
+
+void arg_parse(int argc, char* argv[]) {
+	prog_name = argv[0];
+	if ( argc > 3 )
+		usage("Too many arguments");	
+	port = (argc >= 2)?argv[1]:DEFAULT_PORT_STR;
+	mcast_ip = (argc >= 3)?argv[2]:DEFAULT_MCAST_IP_STR;
+	mcast_ttl = (argc >= 4)?atoi(argv[3]):DEFAULT_MCAST_TTL;
+	if ( mcast_ttl < 1 || mcast_ttl > 64 )
+		mcast_ttl = 1;
+}
+
+void unsetup_sockets() {
+	if ( ucast_sock > 0 ) {
+		close(ucast_sock);
+		ucast_sock = 0;
+	}
+
+	if ( mcast_sock > 0 ) {
+		close(mcast_sock);
+		mcast_sock = 0;
+		if ( mcast_addr ) {
+			freeaddrinfo(mcast_addr);
+			mcast_addr = 0;
+		}
+	}
+}
+
+void setup_sockets() {
+	/* Setup ucast_sock */
+	ucast_sock = ucast_server_socket(port, MAX_PENDING_CONNECTIONS);
+	if(ucast_sock < 0)
+			usage("Could not setup unicast socket. Wrong args given ?");
+
+	/* Setup mcast_sock */
+	mcast_sock = mcast_send_socket(mcast_ip, port, mcast_ttl, &mcast_addr);
+	if(mcast_sock < 0)
+			usage("Could not setup multicast socket. Wrong args given ?");
+}
+
diff --git a/mcastseed/src/msock.c b/mcastseed/src/msock.c
new file mode 100644
index 0000000..8274710
--- /dev/null
+++ b/mcastseed/src/msock.c
@@ -0,0 +1,371 @@
+/*
+  msock.c - multicast socket creation routines
+
+  (C) 2016 Christian Beier <dontmind@sdf.org>
+
+*/
+
+#ifndef __MINGW32__
+#include <unistd.h>
+#endif
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+
+#include "msock.h"
+
+SOCKET mcast_send_socket(char* multicastIP, char* multicastPort,  int multicastTTL, struct addrinfo **multicastAddr) {
+
+    SOCKET sock;
+    struct addrinfo hints = { 0 };    /* Hints for name lookup */
+    
+    
+#ifdef WIN32
+    WSADATA trash;
+    if(WSAStartup(MAKEWORD(2,0),&trash)!=0)
+	DieWithError("Couldn't init Windows Sockets\n");
+#endif
+
+    
+    /*
+      Resolve destination address for multicast datagrams 
+    */
+    hints.ai_family   = PF_UNSPEC;
+    hints.ai_socktype = SOCK_DGRAM;
+    hints.ai_flags    = AI_NUMERICHOST;
+    int status;
+    if ((status = getaddrinfo(multicastIP, multicastPort, &hints, multicastAddr)) != 0 )
+	{
+	    fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(status));
+	    return -1;
+	}
+
+   
+
+    /* 
+       Create socket for sending multicast datagrams 
+    */
+    if ( (sock = socket((*multicastAddr)->ai_family, (*multicastAddr)->ai_socktype, 0)) < 0 ) {
+	perror("socket() failed");
+	freeaddrinfo(*multicastAddr);
+	return -1;
+    }
+
+    /* 
+       Set TTL of multicast packet 
+    */
+    if ( setsockopt(sock,
+		    (*multicastAddr)->ai_family == PF_INET6 ? IPPROTO_IPV6        : IPPROTO_IP,
+		    (*multicastAddr)->ai_family == PF_INET6 ? IPV6_MULTICAST_HOPS : IP_MULTICAST_TTL,
+		    (char*) &multicastTTL, sizeof(multicastTTL)) != 0 ) {
+	perror("setsockopt() failed");
+	freeaddrinfo(*multicastAddr);
+	return -1;
+    }
+    
+    
+    /* 
+       set the sending interface 
+    */
+    if((*multicastAddr)->ai_family == PF_INET) {
+	in_addr_t iface = INADDR_ANY; /* well, yeah, any */
+	if(setsockopt (sock, 
+		       IPPROTO_IP,
+		       IP_MULTICAST_IF,
+		       (char*)&iface, sizeof(iface)) != 0) { 
+	    perror("interface setsockopt() sending interface");
+	    freeaddrinfo(*multicastAddr);
+	    return -1;
+	}
+
+    }
+    if((*multicastAddr)->ai_family == PF_INET6) {
+	unsigned int ifindex = 0; /* 0 means 'default interface'*/
+	if(setsockopt (sock, 
+		       IPPROTO_IPV6,
+		       IPV6_MULTICAST_IF,
+		       (char*)&ifindex, sizeof(ifindex)) != 0) { 
+	    perror("interface setsockopt() sending interface");
+	    freeaddrinfo(*multicastAddr);
+	    return -1;
+	}   
+	 
+    }
+
+     
+    return sock;
+
+}
+
+
+
+SOCKET mcast_recv_socket(char* multicastIP, char* multicastPort, int multicastRecvBufSize) {
+
+    SOCKET sock;
+    struct addrinfo   hints  = { 0 };    /* Hints for name lookup */
+    struct addrinfo*  localAddr = 0;         /* Local address to bind to */
+    struct addrinfo*  multicastAddr = 0;     /* Multicast Address */
+    int yes=1;
+  
+#ifdef WIN32
+    WSADATA trash;
+    if(WSAStartup(MAKEWORD(2,0),&trash)!=0)
+	DieWithError("Couldn't init Windows Sockets\n");
+#endif
+
+    
+    /* Resolve the multicast group address */
+    hints.ai_family = PF_UNSPEC;
+    hints.ai_flags  = AI_NUMERICHOST;
+    int status;
+    if ((status = getaddrinfo(multicastIP, NULL, &hints, &multicastAddr)) != 0) {
+	    fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(status));
+	    goto error;
+    }
+    
+   
+    /* 
+       Get a local address with the same family (IPv4 or IPv6) as our multicast group
+       This is for receiving on a certain port.
+    */
+    hints.ai_family   = multicastAddr->ai_family;
+    hints.ai_socktype = SOCK_DGRAM;
+    hints.ai_flags    = AI_PASSIVE; /* Return an address we can bind to */
+    if ( getaddrinfo(NULL, multicastPort, &hints, &localAddr) != 0 ) {
+	fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(status));
+	goto error;
+    }
+  
+
+    /* Create socket for receiving datagrams */
+    if ( (sock = socket(localAddr->ai_family, localAddr->ai_socktype, 0)) < 0 ) {
+	perror("socket() failed");
+	goto error;
+    }
+    
+    
+   
+    /*
+     * Enable SO_REUSEADDR to allow multiple instances of this
+     * application to receive copies of the multicast datagrams.
+     */
+    if (setsockopt(sock,SOL_SOCKET,SO_REUSEADDR,(char*)&yes,sizeof(int)) == -1) {
+	perror("setsockopt");
+	goto error;
+    }
+  
+    /* Bind the local address to the multicast port */
+    if ( bind(sock, localAddr->ai_addr, localAddr->ai_addrlen) != 0 ) {
+	perror("bind() failed");
+	goto error;
+    }
+
+    /* get/set socket receive buffer */
+    int optval=0;
+    socklen_t optval_len = sizeof(optval);
+    int dfltrcvbuf;
+    if(getsockopt(sock, SOL_SOCKET, SO_RCVBUF,(char*)&optval, &optval_len) !=0) {
+	perror("getsockopt");
+	goto error;
+    }
+    dfltrcvbuf = optval;
+    optval = multicastRecvBufSize;
+    if(setsockopt(sock,SOL_SOCKET,SO_RCVBUF,(char*)&optval,sizeof(optval)) != 0) {
+	perror("setsockopt");
+	goto error;
+    }
+    if(getsockopt(sock, SOL_SOCKET, SO_RCVBUF,(char*)&optval, &optval_len) != 0) {
+	perror("getsockopt");
+	goto error;
+    }
+    printf("tried to set socket receive buffer from %d to %d, got %d\n",
+	   dfltrcvbuf, multicastRecvBufSize, optval);
+
+  
+    
+    
+    /* Join the multicast group. We do this seperately depending on whether we
+     * are using IPv4 or IPv6. 
+     */
+    if ( multicastAddr->ai_family  == PF_INET &&  
+	 multicastAddr->ai_addrlen == sizeof(struct sockaddr_in) ) /* IPv4 */
+	{
+	    struct ip_mreq multicastRequest;  /* Multicast address join structure */
+
+	    /* Specify the multicast group */
+	    memcpy(&multicastRequest.imr_multiaddr,
+		   &((struct sockaddr_in*)(multicastAddr->ai_addr))->sin_addr,
+		   sizeof(multicastRequest.imr_multiaddr));
+
+	    /* Accept multicast from any interface */
+	    multicastRequest.imr_interface.s_addr = htonl(INADDR_ANY);
+
+	    /* Join the multicast address */
+	    if ( setsockopt(sock, IPPROTO_IP, IP_ADD_MEMBERSHIP, (char*) &multicastRequest, sizeof(multicastRequest)) != 0 ) {
+		perror("setsockopt() failed");
+		goto error;
+	    }
+	}
+    else if ( multicastAddr->ai_family  == PF_INET6 &&
+	      multicastAddr->ai_addrlen == sizeof(struct sockaddr_in6) ) /* IPv6 */
+	{
+	    struct ipv6_mreq multicastRequest;  /* Multicast address join structure */
+
+	    /* Specify the multicast group */
+	    memcpy(&multicastRequest.ipv6mr_multiaddr,
+		   &((struct sockaddr_in6*)(multicastAddr->ai_addr))->sin6_addr,
+		   sizeof(multicastRequest.ipv6mr_multiaddr));
+
+	    /* Accept multicast from any interface */
+	    multicastRequest.ipv6mr_interface = 0;
+
+	    /* Join the multicast address */
+	    if ( setsockopt(sock, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, (char*) &multicastRequest, sizeof(multicastRequest)) != 0 ) {
+		perror("setsockopt() failed");
+		goto error;
+	    }
+	}
+    else {
+	perror("Neither IPv4 or IPv6"); 
+  	goto error;
+    }
+
+
+    
+    if(localAddr)
+	freeaddrinfo(localAddr);
+    if(multicastAddr)
+	freeaddrinfo(multicastAddr);
+    
+    return sock;
+
+ error:
+    if(localAddr)
+	freeaddrinfo(localAddr);
+    if(multicastAddr)
+	freeaddrinfo(multicastAddr);
+
+    return -1;
+}
+
+SOCKET ucast_client_socket(char* serverIP, char* serverPort) {
+
+	SOCKET sock;
+	struct addrinfo *serverAddr;
+	struct addrinfo hints = { 0 };    /* Hints for name lookup */
+
+
+#ifdef WIN32
+	WSADATA trash;
+	if(WSAStartup(MAKEWORD(2,0),&trash)!=0)
+		DieWithError("Couldn't init Windows Sockets\n");
+#endif
+
+
+	/*
+		 Resolve destination address
+	 */
+	hints.ai_family   = PF_UNSPEC;
+	hints.ai_socktype = SOCK_STREAM;
+	hints.ai_flags    = AI_NUMERICHOST;
+	int status;
+	if ((status = getaddrinfo(serverIP, serverPort, &hints, &serverAddr)) != 0 )
+	{
+		fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(status));
+		return -1;
+	}
+
+	/* 
+		 Create socket
+	 */
+	if ( (sock = socket(serverAddr->ai_family, serverAddr->ai_socktype, 0)) < 0 ) {
+		perror("socket() failed");
+		freeaddrinfo(serverAddr);
+		return -1;
+	}
+
+	/* 
+		 Connect it to the remote server
+	 */
+	if ( connect(sock, serverAddr->ai_addr, serverAddr->ai_addrlen) < 0 ) {
+		perror("connect() failed");
+		close(sock);
+		freeaddrinfo(serverAddr);
+		return -1;
+	}
+
+	freeaddrinfo(serverAddr);
+	return sock;
+}
+
+SOCKET ucast_server_socket(char* serverPort, int maxPendingConnections) {
+
+	SOCKET sock;
+	struct addrinfo *serverAddr;
+	struct addrinfo hints = { 0 };    /* Hints for name lookup */
+
+
+#ifdef WIN32
+	WSADATA trash;
+	if(WSAStartup(MAKEWORD(2,0),&trash)!=0)
+		DieWithError("Couldn't init Windows Sockets\n");
+#endif
+
+
+	/*
+		 Prepare an addrinfo struct for a local socket
+	 */
+	hints.ai_family   = PF_INET6;
+	hints.ai_socktype = SOCK_STREAM;
+	hints.ai_flags    = AI_PASSIVE;
+	int status;
+	if ((status = getaddrinfo(NULL, serverPort, &hints, &serverAddr)) != 0 )
+	{
+		fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(status));
+		return -1;
+	}
+	/* 
+		 Create socket
+	 */
+	if ( (sock = socket(serverAddr->ai_family, serverAddr->ai_socktype, serverAddr->ai_protocol)) < 0 ) {
+		perror("socket() failed");
+		freeaddrinfo(serverAddr);
+		return -1;
+	}
+
+	/*
+	   Accepts also IPv4 traffic if the socket is INET6
+	 */
+	if(serverAddr->ai_family == PF_INET6) {
+		unsigned int no = 0;
+		if(setsockopt (sock, 
+					IPPROTO_IPV6,
+					IPV6_V6ONLY,
+					(char*)&no, sizeof(no)) != 0) { 
+			perror("setsockopt() !IPV6_V6ONLY failed");
+			freeaddrinfo(serverAddr);
+			return -1;
+		}   
+	}
+	
+	/* 
+		 Bind socket to local address/port
+	 */
+	if ( bind(sock, serverAddr->ai_addr, serverAddr->ai_addrlen) < 0 ) {
+		perror("bind() failed");
+		close(sock);
+		freeaddrinfo(serverAddr);
+		return -1;
+	}
+
+	freeaddrinfo(serverAddr);
+	/*
+	   Start listening incoming connections
+	 */
+	if ( listen(sock, maxPendingConnections) < 0 ) {
+		perror("listen() failed");
+		close(sock);
+	}
+
+	return sock;
+}
diff --git a/mcastseed/src/msock.h b/mcastseed/src/msock.h
new file mode 100644
index 0000000..07e1fad
--- /dev/null
+++ b/mcastseed/src/msock.h
@@ -0,0 +1,74 @@
+/*
+  msock.h - multicast socket creation routines
+
+  (C) 2016 Christian Beier <dontmind@sdf.org>
+
+*/
+
+
+#ifndef MSOCK_H
+#define MSOCK_H
+
+/* this is for windows compat */
+#define SOCKET int
+
+#ifdef __MINGW32__ 
+#undef SOCKET
+#undef socklen_t 
+#define WINVER 0x0501 
+#include <ws2tcpip.h> 
+#define EWOULDBLOCK WSAEWOULDBLOCK
+#define close closesocket
+#define socklen_t int
+typedef unsigned int in_addr_t;
+#else
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <sys/un.h>
+#include <netinet/tcp.h>
+#include <arpa/inet.h>
+#include <netdb.h>
+#endif
+
+/* Define IPV6_ADD_MEMBERSHIP for FreeBSD and Mac OS X */
+#ifndef IPV6_ADD_MEMBERSHIP
+#define IPV6_ADD_MEMBERSHIP IPV6_JOIN_GROUP
+#endif
+
+
+
+/**
+   Creates a socket suitable for sending multicast datagrams via sendto().
+
+   On success, a socket is returned and multicastAddr set with the right info for sendto() calls.
+   On error, -1 is returned.
+*/
+SOCKET mcast_send_socket(char* multicastIP, char* multicastPort,  int multicastTTL, struct addrinfo **multicastAddr);
+
+/**
+   Creates a socket suitable for receiving multicast datagrams via recvfrom(). Also sets socket recv buffer.
+   
+   On success, returns socket.
+   On fail, returns -1.
+ */
+SOCKET mcast_recv_socket(char* multicastIP, char* multicastPort, int multicastRecvBufSize);
+
+/**
+   Creates a TCP socket that connects to serverIP:serverPort. 
+   Meant to give feedback to a mcast sender.
+  
+   On success, returns socket.
+   On error, -1 is returned.
+ */
+SOCKET ucast_client_socket(char* serverIP, char* serverPort);
+
+/**
+   Creates a TCP socket that binds locally serverPort. 
+   Meant to receive feedback to a mcast sender.
+  
+   On success, returns socket.
+   On error, -1 is returned.
+ */
+SOCKET ucast_server_socket(char* serverPort, int maxPendingConnections);
+
+#endif