From 6347ad8c810f62078d875ba4bd37c47d1e77d1b7 Mon Sep 17 00:00:00 2001
From: Michael Tuexen <tuexen@fh-muenster.de>
Date: Thu, 11 Jan 2018 00:08:23 +0100
Subject: [PATCH] Update TCP Fast Open support to RFC 7413.
Use the IANA assigned option number for the TCP Fast Open option.
Use EXP-FO instead of TO for using the deprecate experimental option.
---
gtests/net/packetdrill/lexer.l | 1 +
gtests/net/packetdrill/parser.y | 58 +++++++++++++++++--
gtests/net/packetdrill/tcp.h | 1 +
gtests/net/packetdrill/tcp_options.h | 21 ++++++-
gtests/net/packetdrill/tcp_options_iterator.c | 1 +
.../net/packetdrill/tcp_options_to_string.c | 42 ++++++++++++--
6 files changed, 110 insertions(+), 14 deletions(-)
diff --git a/gtests/net/packetdrill/lexer.l b/gtests/net/packetdrill/lexer.l
index f0876095..ea3c647d 100644
--- a/gtests/net/packetdrill/lexer.l
+++ b/gtests/net/packetdrill/lexer.l
@@ -320,6 +320,7 @@ nop return NOP;
sack return SACK;
sackOK return SACKOK;
TS return TIMESTAMP;
+EXP-FO return EXP_FAST_OPEN;
FO return FAST_OPEN;
val return VAL;
win return WIN;
diff --git a/gtests/net/packetdrill/parser.y b/gtests/net/packetdrill/parser.y
index 80d421e4..db2b43f4 100644
--- a/gtests/net/packetdrill/parser.y
+++ b/gtests/net/packetdrill/parser.y
@@ -399,7 +399,7 @@ static int parse_hex_string(const char *hex, u8 *buf, int buf_len,
}
static struct tcp_option *new_tcp_fast_open_option(const char *cookie_string,
- char **error)
+ char **error)
{
int cookie_string_len = strlen(cookie_string);
if (cookie_string_len & 1) {
@@ -415,10 +415,9 @@ static struct tcp_option *new_tcp_fast_open_option(const char *cookie_string,
cookie_bytes, MAX_TCP_FAST_OPEN_COOKIE_BYTES);
return NULL;
}
- u8 option_bytes = TCPOLEN_EXP_FASTOPEN_BASE + cookie_bytes;
+ u8 option_bytes = TCPOLEN_FASTOPEN_BASE + cookie_bytes;
struct tcp_option *option;
- option = tcp_option_new(TCPOPT_EXP, option_bytes);
- option->data.fast_open.magic = htons(TCPOPT_FASTOPEN_MAGIC);
+ option = tcp_option_new(TCPOPT_FASTOPEN, option_bytes);
int parsed_bytes = 0;
/* Parse cookie. This should be an ASCII hex string
* representing an even number of bytes (4-16 bytes). But we
@@ -437,6 +436,45 @@ static struct tcp_option *new_tcp_fast_open_option(const char *cookie_string,
return option;
}
+static struct tcp_option *new_tcp_exp_fast_open_option(const char *cookie_string,
+ char **error)
+{
+ int cookie_string_len = strlen(cookie_string);
+ if (cookie_string_len & 1) {
+ asprintf(error,
+ "TCP fast open cookie has an odd number of digits");
+ return NULL;
+ }
+ int cookie_bytes = cookie_string_len / 2; /* 2 hex chars per byte */
+ if (cookie_bytes > MAX_TCP_EXP_FAST_OPEN_COOKIE_BYTES) {
+ asprintf(error, "TCP fast open cookie too long");
+ asprintf(error, "TCP fast open cookie of %d bytes "
+ "exceeds maximum cookie length of %d bytes",
+ cookie_bytes, MAX_TCP_EXP_FAST_OPEN_COOKIE_BYTES);
+ return NULL;
+ }
+ u8 option_bytes = TCPOLEN_EXP_FASTOPEN_BASE + cookie_bytes;
+ struct tcp_option *option;
+ option = tcp_option_new(TCPOPT_EXP, option_bytes);
+ option->data.exp_fast_open.magic = htons(TCPOPT_FASTOPEN_MAGIC);
+ int parsed_bytes = 0;
+ /* Parse cookie. This should be an ASCII hex string
+ * representing an even number of bytes (4-16 bytes). But we
+ * do not enforce this, since we want to allow test cases that
+ * supply invalid cookies.
+ */
+ if (parse_hex_string(cookie_string, option->data.exp_fast_open.cookie,
+ sizeof(option->data.exp_fast_open.cookie),
+ &parsed_bytes)) {
+ free(option);
+ asprintf(error,
+ "TCP fast open cookie is not a valid hex string");
+ return NULL;
+ }
+ assert(parsed_bytes == cookie_bytes);
+ return option;
+}
+
%}
%locations
@@ -525,7 +563,7 @@ static struct tcp_option *new_tcp_fast_open_option(const char *cookie_string,
%token <reserved> SF_HDTR_HEADERS SF_HDTR_TRAILERS
%token <reserved> FD EVENTS REVENTS ONOFF LINGER
%token <reserved> ACK ECR EOL MSS NOP SACK NR_SACK SACKOK TIMESTAMP VAL WIN WSCALE PRO
-%token <reserved> FAST_OPEN
+%token <reserved> EXP_FAST_OPEN FAST_OPEN
%token <reserved> IOV_BASE IOV_LEN
%token <reserved> ECT0 ECT1 CE ECT01 NO_ECN
%token <reserved> IPV4 IPV6 ICMP SCTP UDP UDPLITE GRE MTU
@@ -2752,6 +2790,16 @@ tcp_option
free(error);
}
}
+| EXP_FAST_OPEN opt_tcp_fast_open_cookie {
+ char *error = NULL;
+ $$ = new_tcp_exp_fast_open_option($2, &error);
+ free($2);
+ if ($$ == NULL) {
+ assert(error != NULL);
+ semantic_error(error);
+ free(error);
+ }
+}
;
abs_integer
diff --git a/gtests/net/packetdrill/tcp.h b/gtests/net/packetdrill/tcp.h
index c07bdb8f..fbc8edbd 100644
--- a/gtests/net/packetdrill/tcp.h
+++ b/gtests/net/packetdrill/tcp.h
@@ -85,6 +85,7 @@
#define TCPOPT_SACK 5
#define TCPOPT_TIMESTAMP 8
#define TCPOLEN_TIMESTAMP 10
+#define TCPOPT_FASTOPEN 34
#define TCPOPT_EXP 254 /* Experimental */
/* A portable TCP header definition (Linux and *BSD use different names). */
diff --git a/gtests/net/packetdrill/tcp_options.h b/gtests/net/packetdrill/tcp_options.h
index 3fb8231c..34ae671c 100644
--- a/gtests/net/packetdrill/tcp_options.h
+++ b/gtests/net/packetdrill/tcp_options.h
@@ -35,10 +35,10 @@
* option value for sharing TCP experimental options.
*
* For a description of experimental options, see:
- * http://tools.ietf.org/html/draft-ietf-tcpm-experimental-options-00
+ * https://tools.ietf.org/html/rfc6994
*
* For a description of TFO, see:
- * http://tools.ietf.org/html/draft-cheng-tcpm-fastopen-02
+ * https://tools.ietf.org/html/rfc7413
*/
#define TCPOPT_FASTOPEN_MAGIC 0xF989
@@ -46,9 +46,16 @@
#define TCPOLEN_EXP_FASTOPEN_BASE 4 /* smallest legal TFO option size */
/* The TFO option base prefix leaves this amount of space: */
-#define MAX_TCP_FAST_OPEN_COOKIE_BYTES \
+#define MAX_TCP_EXP_FAST_OPEN_COOKIE_BYTES \
(MAX_TCP_OPTION_BYTES - TCPOLEN_EXP_FASTOPEN_BASE)
+/* TFO option must have: 1-byte kind, 1-byte length */
+#define TCPOLEN_FASTOPEN_BASE 2 /* smallest legal TFO option size */
+
+/* The TFO option base prefix leaves this amount of space: */
+#define MAX_TCP_FAST_OPEN_COOKIE_BYTES \
+ (MAX_TCP_OPTION_BYTES - TCPOLEN_FASTOPEN_BASE)
+
/* Represents a list of TCP options in their wire format. */
struct tcp_options {
u8 data[MAX_TCP_OPTION_BYTES]; /* The options data, in wire format */
@@ -85,6 +92,14 @@ struct tcp_option {
} sack;
struct {
u16 magic; /* must be TCPOPT_FASTOPEN_MAGIC */
+ /* The fast open chookie should be 4-16 bytes
+ * of cookie, multiple of 2 bytes, but we
+ * allow for larger sizes, so we can test what
+ * stacks do with illegal options.
+ */
+ u8 cookie[MAX_TCP_EXP_FAST_OPEN_COOKIE_BYTES];
+ } exp_fast_open;
+ struct {
/* The fast open chookie should be 4-16 bytes
* of cookie, multiple of 2 bytes, but we
* allow for larger sizes, so we can test what
diff --git a/gtests/net/packetdrill/tcp_options_iterator.c b/gtests/net/packetdrill/tcp_options_iterator.c
index 90257eb0..1ec8dd81 100644
--- a/gtests/net/packetdrill/tcp_options_iterator.c
+++ b/gtests/net/packetdrill/tcp_options_iterator.c
@@ -62,6 +62,7 @@ static int get_expected_tcp_option_length(u8 kind, u8 *expected_length,
break;
case TCPOPT_SACK:
+ case TCPOPT_FASTOPEN:
case TCPOPT_EXP:
*expected_length = 0; /* variable-length option */
break;
diff --git a/gtests/net/packetdrill/tcp_options_to_string.c b/gtests/net/packetdrill/tcp_options_to_string.c
index d022ec2c..d23ecd30 100644
--- a/gtests/net/packetdrill/tcp_options_to_string.c
+++ b/gtests/net/packetdrill/tcp_options_to_string.c
@@ -26,23 +26,45 @@
#include "tcp_options_iterator.h"
+static int tcp_fast_open_option_to_string(FILE *s, struct tcp_option *option)
+{
+ if (option->length < TCPOLEN_FASTOPEN_BASE) {
+ return STATUS_ERR;
+ }
+
+ fputs("FO", s);
+ int cookie_bytes = option->length - TCPOLEN_FASTOPEN_BASE;
+ assert(cookie_bytes >= 0);
+ assert(cookie_bytes <= MAX_TCP_FAST_OPEN_COOKIE_BYTES);
+ if (cookie_bytes > 0) {
+ fputs(" ", s);
+ }
+ int i;
+ for (i = 0; i < cookie_bytes; ++i)
+ fprintf(s, "%02x", option->data.fast_open.cookie[i]);
+ return STATUS_OK;
+}
+
/* See if the given experimental option is a TFO option, and if so
* then print the TFO option and return STATUS_OK. Otherwise, return
* STATUS_ERR.
*/
-static int tcp_fast_open_option_to_string(FILE *s, struct tcp_option *option)
+static int tcp_exp_fast_open_option_to_string(FILE *s, struct tcp_option *option)
{
if ((option->length < TCPOLEN_EXP_FASTOPEN_BASE) ||
- (ntohs(option->data.fast_open.magic) != TCPOPT_FASTOPEN_MAGIC))
+ (ntohs(option->data.exp_fast_open.magic) != TCPOPT_FASTOPEN_MAGIC))
return STATUS_ERR;
- fprintf(s, "FO ");
+ fputs("EXP-FO", s);
int cookie_bytes = option->length - TCPOLEN_EXP_FASTOPEN_BASE;
assert(cookie_bytes >= 0);
- assert(cookie_bytes <= MAX_TCP_FAST_OPEN_COOKIE_BYTES);
+ assert(cookie_bytes <= MAX_TCP_EXP_FAST_OPEN_COOKIE_BYTES);
+ if (cookie_bytes > 0) {
+ fputs(" ", s);
+ }
int i;
for (i = 0; i < cookie_bytes; ++i)
- fprintf(s, "%02x", option->data.fast_open.cookie[i]);
+ fprintf(s, "%02x", option->data.exp_fast_open.cookie[i]);
return STATUS_OK;
}
@@ -106,8 +128,16 @@ int tcp_options_to_string(struct packet *packet,
ntohl(option->data.time_stamp.ecr));
break;
- case TCPOPT_EXP:
+ case TCPOPT_FASTOPEN:
if (tcp_fast_open_option_to_string(s, option)) {
+ asprintf(error, "invalid length: %u",
+ option->length);
+ goto out;
+ }
+ break;
+
+ case TCPOPT_EXP:
+ if (tcp_exp_fast_open_option_to_string(s, option)) {
asprintf(error,
"unknown experimental option");
goto out;
--
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