diff --git a/src/tcp_sample.c b/src/tcp_sample.c
new file mode 100644
index 0000000..5f1aa1f
--- /dev/null
+++ b/src/tcp_sample.c
@@ -0,0 +1,415 @@
+/*
+ * AF_INET/AF_INET6 SOCK_STREAM protocol layer (tcp)
+ *
+ * Copyright 2000-2013 Willy Tarreau <w@1wt.eu>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ */
+
+/* this is to have tcp_info defined on systems using musl
+ * library, such as Alpine Linux.
+ */
+#define _GNU_SOURCE
+
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+
+#include <sys/param.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+
+#include <netinet/tcp.h>
+#include <netinet/in.h>
+
+#include <haproxy/api.h>
+#include <haproxy/arg.h>
+#include <haproxy/connection.h>
+#include <haproxy/global.h>
+#include <haproxy/listener-t.h>
+#include <haproxy/namespace.h>
+#include <haproxy/proxy-t.h>
+#include <haproxy/sample.h>
+#include <haproxy/tools.h>
+
+
+/* Fetch the connection's source IPv4/IPv6 address. Note that this is also
+ * directly called by stick_table.c and as such must remain publicly visible.
+ */
+static int
+smp_fetch_src(const struct arg *args, struct sample *smp, const char *kw, void *private)
+{
+	struct connection *cli_conn = objt_conn(smp->sess->origin);
+
+	if (!cli_conn)
+		return 0;
+
+	if (!conn_get_src(cli_conn))
+		return 0;
+
+	switch (cli_conn->src->ss_family) {
+	case AF_INET:
+		smp->data.u.ipv4 = ((struct sockaddr_in *)cli_conn->src)->sin_addr;
+		smp->data.type = SMP_T_IPV4;
+		break;
+	case AF_INET6:
+		smp->data.u.ipv6 = ((struct sockaddr_in6 *)cli_conn->src)->sin6_addr;
+		smp->data.type = SMP_T_IPV6;
+		break;
+	default:
+		return 0;
+	}
+
+	smp->flags = 0;
+	return 1;
+}
+
+/* set temp integer to the connection's source port */
+static int
+smp_fetch_sport(const struct arg *args, struct sample *smp, const char *k, void *private)
+{
+	struct connection *cli_conn = objt_conn(smp->sess->origin);
+
+	if (!cli_conn)
+		return 0;
+
+	if (!conn_get_src(cli_conn))
+		return 0;
+
+	smp->data.type = SMP_T_SINT;
+	if (!(smp->data.u.sint = get_host_port(cli_conn->src)))
+		return 0;
+
+	smp->flags = 0;
+	return 1;
+}
+
+/* fetch the connection's destination IPv4/IPv6 address */
+static int
+smp_fetch_dst(const struct arg *args, struct sample *smp, const char *kw, void *private)
+{
+	struct connection *cli_conn = objt_conn(smp->sess->origin);
+
+	if (!cli_conn)
+		return 0;
+
+	if (!conn_get_dst(cli_conn))
+		return 0;
+
+	switch (cli_conn->dst->ss_family) {
+	case AF_INET:
+		smp->data.u.ipv4 = ((struct sockaddr_in *)cli_conn->dst)->sin_addr;
+		smp->data.type = SMP_T_IPV4;
+		break;
+	case AF_INET6:
+		smp->data.u.ipv6 = ((struct sockaddr_in6 *)cli_conn->dst)->sin6_addr;
+		smp->data.type = SMP_T_IPV6;
+		break;
+	default:
+		return 0;
+	}
+
+	smp->flags = 0;
+	return 1;
+}
+
+/* check if the destination address of the front connection is local to the
+ * system or if it was intercepted.
+ */
+int smp_fetch_dst_is_local(const struct arg *args, struct sample *smp, const char *kw, void *private)
+{
+	struct connection *conn = objt_conn(smp->sess->origin);
+	struct listener *li = smp->sess->listener;
+
+	if (!conn)
+		return 0;
+
+	if (!conn_get_dst(conn))
+		return 0;
+
+	smp->data.type = SMP_T_BOOL;
+	smp->flags = 0;
+	smp->data.u.sint = addr_is_local(li->netns, conn->dst);
+	return smp->data.u.sint >= 0;
+}
+
+/* check if the source address of the front connection is local to the system
+ * or not.
+ */
+int smp_fetch_src_is_local(const struct arg *args, struct sample *smp, const char *kw, void *private)
+{
+	struct connection *conn = objt_conn(smp->sess->origin);
+	struct listener *li = smp->sess->listener;
+
+	if (!conn)
+		return 0;
+
+	if (!conn_get_src(conn))
+		return 0;
+
+	smp->data.type = SMP_T_BOOL;
+	smp->flags = 0;
+	smp->data.u.sint = addr_is_local(li->netns, conn->src);
+	return smp->data.u.sint >= 0;
+}
+
+/* set temp integer to the frontend connexion's destination port */
+static int
+smp_fetch_dport(const struct arg *args, struct sample *smp, const char *kw, void *private)
+{
+	struct connection *cli_conn = objt_conn(smp->sess->origin);
+
+	if (!cli_conn)
+		return 0;
+
+	if (!conn_get_dst(cli_conn))
+		return 0;
+
+	smp->data.type = SMP_T_SINT;
+	if (!(smp->data.u.sint = get_host_port(cli_conn->dst)))
+		return 0;
+
+	smp->flags = 0;
+	return 1;
+}
+
+#ifdef TCP_INFO
+
+
+/* Validates the arguments passed to "fc_*" fetch keywords returning a time
+ * value. These keywords support an optional string representing the unit of the
+ * result: "us" for microseconds and "ms" for milliseconds". Returns 0 on error
+ * and non-zero if OK.
+ */
+static int val_fc_time_value(struct arg *args, char **err)
+{
+	if (args[0].type == ARGT_STR) {
+		if (strcmp(args[0].data.str.area, "us") == 0) {
+			chunk_destroy(&args[0].data.str);
+			args[0].type = ARGT_SINT;
+			args[0].data.sint = TIME_UNIT_US;
+		}
+		else if (strcmp(args[0].data.str.area, "ms") == 0) {
+			chunk_destroy(&args[0].data.str);
+			args[0].type = ARGT_SINT;
+			args[0].data.sint = TIME_UNIT_MS;
+		}
+		else {
+			memprintf(err, "expects 'us' or 'ms', got '%s'",
+				  args[0].data.str.area);
+			return 0;
+		}
+	}
+	else {
+		memprintf(err, "Unexpected arg type");
+		return 0;
+	}
+
+	return 1;
+}
+
+/* Validates the arguments passed to "fc_*" fetch keywords returning a
+ * counter. These keywords should be used without any keyword, but because of a
+ * bug in previous versions, an optional string argument may be passed. In such
+ * case, the argument is ignored and a warning is emitted. Returns 0 on error
+ * and non-zero if OK.
+ */
+static int var_fc_counter(struct arg *args, char **err)
+{
+	if (args[0].type != ARGT_STOP) {
+		ha_warning("no argument supported for 'fc_*' sample expressions returning counters.\n");
+		if (args[0].type == ARGT_STR)
+			chunk_destroy(&args[0].data.str);
+		args[0].type = ARGT_STOP;
+	}
+
+	return 1;
+}
+
+/* Returns some tcp_info data if it's available. "dir" must be set to 0 if
+ * the client connection is required, otherwise it is set to 1. "val" represents
+ * the required value.
+ * If the function fails it returns 0, otherwise it returns 1 and "result" is filled.
+ */
+static inline int get_tcp_info(const struct arg *args, struct sample *smp,
+                               int dir, int val)
+{
+	struct connection *conn;
+	struct tcp_info info;
+	socklen_t optlen;
+
+	/* strm can be null. */
+	if (!smp->strm)
+		return 0;
+
+	/* get the object associated with the stream interface.The
+	 * object can be other thing than a connection. For example,
+	 * it be a appctx. */
+	conn = cs_conn(objt_cs(smp->strm->si[dir].end));
+	if (!conn)
+		return 0;
+
+	/* The fd may not be available for the tcp_info struct, and the
+	  syscal can fail. */
+	optlen = sizeof(info);
+	if (getsockopt(conn->handle.fd, SOL_TCP, TCP_INFO, &info, &optlen) == -1)
+		return 0;
+
+	/* extract the value. */
+	smp->data.type = SMP_T_SINT;
+	switch (val) {
+	case 0:  smp->data.u.sint = info.tcpi_rtt;            break;
+	case 1:  smp->data.u.sint = info.tcpi_rttvar;         break;
+#if defined(__linux__)
+	/* these ones are common to all Linux versions */
+	case 2:  smp->data.u.sint = info.tcpi_unacked;        break;
+	case 3:  smp->data.u.sint = info.tcpi_sacked;         break;
+	case 4:  smp->data.u.sint = info.tcpi_lost;           break;
+	case 5:  smp->data.u.sint = info.tcpi_retrans;        break;
+	case 6:  smp->data.u.sint = info.tcpi_fackets;        break;
+	case 7:  smp->data.u.sint = info.tcpi_reordering;     break;
+#elif defined(__FreeBSD__) || defined(__NetBSD__)
+	/* the ones are found on FreeBSD and NetBSD featuring TCP_INFO */
+	case 2:  smp->data.u.sint = info.__tcpi_unacked;      break;
+	case 3:  smp->data.u.sint = info.__tcpi_sacked;       break;
+	case 4:  smp->data.u.sint = info.__tcpi_lost;         break;
+	case 5:  smp->data.u.sint = info.__tcpi_retrans;      break;
+	case 6:  smp->data.u.sint = info.__tcpi_fackets;      break;
+	case 7:  smp->data.u.sint = info.__tcpi_reordering;   break;
+#endif
+	default: return 0;
+	}
+
+	return 1;
+}
+
+/* get the mean rtt of a client connection */
+static int
+smp_fetch_fc_rtt(const struct arg *args, struct sample *smp, const char *kw, void *private)
+{
+	if (!get_tcp_info(args, smp, 0, 0))
+		return 0;
+
+	/* By default or if explicitly specified, convert rtt to ms */
+	if (!args || args[0].type == ARGT_STOP || args[0].data.sint == TIME_UNIT_MS)
+		smp->data.u.sint = (smp->data.u.sint + 500) / 1000;
+
+	return 1;
+}
+
+/* get the variance of the mean rtt of a client connection */
+static int
+smp_fetch_fc_rttvar(const struct arg *args, struct sample *smp, const char *kw, void *private)
+{
+	if (!get_tcp_info(args, smp, 0, 1))
+		return 0;
+
+	/* By default or if explicitly specified, convert rttvar to ms */
+	if (!args || args[0].type == ARGT_STOP || args[0].data.sint == TIME_UNIT_MS)
+		smp->data.u.sint = (smp->data.u.sint + 500) / 1000;
+
+	return 1;
+}
+
+#if defined(__linux__) || defined(__FreeBSD__) || defined(__NetBSD__)
+
+/* get the unacked counter on a client connection */
+static int
+smp_fetch_fc_unacked(const struct arg *args, struct sample *smp, const char *kw, void *private)
+{
+	if (!get_tcp_info(args, smp, 0, 2))
+		return 0;
+	return 1;
+}
+
+/* get the sacked counter on a client connection */
+static int
+smp_fetch_fc_sacked(const struct arg *args, struct sample *smp, const char *kw, void *private)
+{
+	if (!get_tcp_info(args, smp, 0, 3))
+		return 0;
+	return 1;
+}
+
+/* get the lost counter on a client connection */
+static int
+smp_fetch_fc_lost(const struct arg *args, struct sample *smp, const char *kw, void *private)
+{
+	if (!get_tcp_info(args, smp, 0, 4))
+		return 0;
+	return 1;
+}
+
+/* get the retrans counter on a client connection */
+static int
+smp_fetch_fc_retrans(const struct arg *args, struct sample *smp, const char *kw, void *private)
+{
+	if (!get_tcp_info(args, smp, 0, 5))
+		return 0;
+	return 1;
+}
+
+/* get the fackets counter on a client connection */
+static int
+smp_fetch_fc_fackets(const struct arg *args, struct sample *smp, const char *kw, void *private)
+{
+	if (!get_tcp_info(args, smp, 0, 6))
+		return 0;
+	return 1;
+}
+
+/* get the reordering counter on a client connection */
+static int
+smp_fetch_fc_reordering(const struct arg *args, struct sample *smp, const char *kw, void *private)
+{
+	if (!get_tcp_info(args, smp, 0, 7))
+		return 0;
+	return 1;
+}
+#endif // linux || freebsd || netbsd
+#endif // TCP_INFO
+
+/* Note: must not be declared <const> as its list will be overwritten.
+ * Note: fetches that may return multiple types must be declared as the lowest
+ * common denominator, the type that can be casted into all other ones. For
+ * instance v4/v6 must be declared v4.
+ */
+static struct sample_fetch_kw_list sample_fetch_keywords = {ILH, {
+	{ "dst",      smp_fetch_dst,   0, NULL, SMP_T_IPV4, SMP_USE_L4CLI },
+	{ "dst_is_local", smp_fetch_dst_is_local, 0, NULL, SMP_T_BOOL, SMP_USE_L4CLI },
+	{ "dst_port", smp_fetch_dport, 0, NULL, SMP_T_SINT, SMP_USE_L4CLI },
+	{ "src",      smp_fetch_src,   0, NULL, SMP_T_IPV4, SMP_USE_L4CLI },
+	{ "src_is_local", smp_fetch_src_is_local, 0, NULL, SMP_T_BOOL, SMP_USE_L4CLI },
+	{ "src_port", smp_fetch_sport, 0, NULL, SMP_T_SINT, SMP_USE_L4CLI },
+#ifdef TCP_INFO
+	{ "fc_rtt",           smp_fetch_fc_rtt,           ARG1(0,STR), val_fc_time_value, SMP_T_SINT, SMP_USE_L4CLI },
+	{ "fc_rttvar",        smp_fetch_fc_rttvar,        ARG1(0,STR), val_fc_time_value, SMP_T_SINT, SMP_USE_L4CLI },
+#if defined(__linux__) || defined(__FreeBSD__) || defined(__NetBSD__)
+	{ "fc_unacked",       smp_fetch_fc_unacked,       ARG1(0,STR), var_fc_counter, SMP_T_SINT, SMP_USE_L4CLI },
+	{ "fc_sacked",        smp_fetch_fc_sacked,        ARG1(0,STR), var_fc_counter, SMP_T_SINT, SMP_USE_L4CLI },
+	{ "fc_retrans",       smp_fetch_fc_retrans,       ARG1(0,STR), var_fc_counter, SMP_T_SINT, SMP_USE_L4CLI },
+	{ "fc_fackets",       smp_fetch_fc_fackets,       ARG1(0,STR), var_fc_counter, SMP_T_SINT, SMP_USE_L4CLI },
+	{ "fc_lost",          smp_fetch_fc_lost,          ARG1(0,STR), var_fc_counter, SMP_T_SINT, SMP_USE_L4CLI },
+	{ "fc_reordering",    smp_fetch_fc_reordering,    ARG1(0,STR), var_fc_counter, SMP_T_SINT, SMP_USE_L4CLI },
+#endif // linux || freebsd || netbsd
+#endif // TCP_INFO
+	{ /* END */ },
+}};
+
+INITCALL1(STG_REGISTER, sample_register_fetches, &sample_fetch_keywords);
+
+
+/*
+ * Local variables:
+ *  c-indent-level: 8
+ *  c-basic-offset: 8
+ * End:
+ */