Merge pull request #9 from appneta/Enhancement_pseudo_crc

Enhancement pseudo crc
appneta · Dec 5, 2013 · d3eb0a7 · d3eb0a7
2 parents 8481a8a + 5f029c3
commit d3eb0a7
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Showing 10 changed files with 153 additions and 21 deletions.
diff --git a/docs/CHANGELOG b/docs/CHANGELOG
@@ -1,7 +1,9 @@
 $Id$
 
 ??/??/2013 Version 3.5.0
-    - Removed sleep-accel option (anneta #2) 
+    - Implement pseudo-CRC to improve tcpedit performance (appneta #8)
+    - Add --fast-flows option to tcpreplay (appneta #4)
+    - Removed sleep-accel option (appneta #2) 
     - Enhance accuracy and performance of --mbps option (appneta #2)
     - Add netmap injector (appneta #1)
     - Add --sleepmode option to handle high precision timing (#421)

diff --git a/docs/CREDIT b/docs/CREDIT
@@ -1,7 +1,8 @@
 $Id$ 
 
 tcpreplay and it's associated utilities (tcpprep, tcprewrite and flowreplay)
-were designed and written by Aaron Turner.
+were designed and written by Aaron Turner, and maintained by Fred Klassen
+of AppNeta Inc.
 
 This product includes software developed by the University of California,
 Berkeley, Lawrence Berkeley Laboratory and its contributors. 
@@ -57,7 +58,10 @@ Bojan Smojver <[email protected]>
 Stas Grabois <[email protected]>
     - For his efforts to add IPv6 support to tcpprep and the tcpedit engine
     - For adding IPv6 support to fragroute
-
+    
 Fred Klassen - AppNeta Inc. <fklassen at appneta dot com>
     - Added netmap support for wire-rate performance on commodity hardware
     - Improve accuracy and performance of the --mbps option
+    - Implement pseudo-CRC to improve tcpedit performance
+    - Add --fast-flows option to tcpreplay
+
diff --git a/src/send_packets.c b/src/send_packets.c
@@ -220,7 +220,7 @@ send_packets(pcap_t *pcap, int cache_file_idx)
 #endif
 #if defined TCPREPLAY && !defined TCPREPLAY_EDIT
     static u_int32_t iteration = 0;
-    int datalink = options.int1dlt;
+    int datalink = options.intf1dlt;
 #endif
     COUNTER skip_length = 0;
     COUNTER start_us;
@@ -401,7 +401,7 @@ send_dual_packets(pcap_t *pcap1, int cache_file_idx1, pcap_t *pcap2, int cache_f
     struct pcap_pkthdr *pkthdr_ptr;
 #if defined TCPREPLAY && !defined TCPREPLAY_EDIT
     static u_int32_t iteration = 0;
-    int datalink = options.int1dlt;
+    int datalink = options.intf1dlt;
 #endif
     COUNTER start_us;
     COUNTER skip_length = 0;
@@ -456,7 +456,7 @@ send_dual_packets(pcap_t *pcap1, int cache_file_idx1, pcap_t *pcap2, int cache_f
             /* file 2 is next */
             sp = options.intf2;
 #if defined TCPREPLAY && !defined TCPREPLAY_EDIT
-            datalink = options.int2dlt;
+            datalink = options.intf2dlt;
 #endif
             pcap = pcap2;
             pkthdr_ptr = &pkthdr2;
@@ -467,7 +467,7 @@ send_dual_packets(pcap_t *pcap1, int cache_file_idx1, pcap_t *pcap2, int cache_f
             /* file 1 is next */
             sp = options.intf1;
 #if defined TCPREPLAY && !defined TCPREPLAY_EDIT
-            datalink = options.int1dlt;
+            datalink = options.intf1dlt;
 #endif
             pcap = pcap1;
             pkthdr_ptr = &pkthdr1;
@@ -478,7 +478,7 @@ send_dual_packets(pcap_t *pcap1, int cache_file_idx1, pcap_t *pcap2, int cache_f
             /* file 1 is next */
             sp = options.intf1;
 #if defined TCPREPLAY && !defined TCPREPLAY_EDIT
-            datalink = options.int1dlt;
+            datalink = options.intf1dlt;
 #endif
             pcap = pcap1;
             pkthdr_ptr = &pkthdr1;
@@ -489,7 +489,7 @@ send_dual_packets(pcap_t *pcap1, int cache_file_idx1, pcap_t *pcap2, int cache_f
             /* file 2 is next */
             sp = options.intf2;
 #if defined TCPREPLAY && !defined TCPREPLAY_EDIT
-            datalink = options.int2dlt;
+            datalink = options.intf2dlt;
 #endif
             pcap = pcap2;
             pkthdr_ptr = &pkthdr2;

diff --git a/src/tcpedit/checksum.c b/src/tcpedit/checksum.c
@@ -41,6 +41,55 @@
 
 static int do_checksum_math(u_int16_t *, int);
 
+/*
+ * Fold a partial checksum
+ *
+ * shamelessly stolen from Linux kernel and modified
+ * to run in user land
+ */
+static inline u_int16_t csum_fold(u_int32_t csum)
+{
+    u_int32_t sum = csum;
+    sum = (sum & 0xffff) + (sum >> 16);
+    sum = (sum & 0xffff) + (sum >> 16);
+    return (u_int16_t)~sum;
+}
+
+static inline u_int32_t csum_partial(void *buff, int len, u_int32_t wsum)
+{
+    unsigned int sum = (unsigned int)wsum;
+    unsigned int result = do_checksum_math(buff, len);
+
+    /* add in old sum, and carry.. */
+    result += sum;
+    if (sum > result)
+        result += 1;
+    return (u_int32_t)result;
+}
+
+static inline void __chksum_replace4(u_int16_t *sum, u_int32_t from, u_int32_t to)
+{
+    u_int32_t diff[] = { ~from, to };
+    *sum = csum_fold(csum_partial(diff, sizeof(diff), ~((u_int32_t)(*sum))));
+}
+
+/**
+ * Apply modifications to an existing checksum based on
+ * 32-bit before and after values
+ */
+void chksum_replace4(u_int16_t *sum, u_int32_t from, u_int32_t to)
+{
+    __chksum_replace4(sum, from, to);
+}
+
+/**
+ * Apply modifications to an existing checksum based on
+ * 32-bit before and after values
+ */
+void chksum_replace2(u_int16_t *sum, u_int16_t from, u_int16_t to)
+{
+    __chksum_replace4(sum, (u_int32_t)from, (u_int32_t)to);
+}
 
 /**
  * Returns -1 on error and 0 on success, 1 on warn

diff --git a/src/tcpedit/checksum.h b/src/tcpedit/checksum.h
@@ -37,5 +37,7 @@
     (x = (x >> 16) + (x & 0xffff), (~(x + (x >> 16)) & 0xffff))
 
 int do_checksum(tcpedit_t *, u_int8_t *, int, int);
+void chksum_replace4(u_int16_t *sum, u_int32_t from, u_int32_t to);
+void ckksum_replace2(u_int16_t *sum, u_int16_t from, u_int16_t to);
 
 #endif
diff --git a/src/tcpedit/edit_packet.c b/src/tcpedit/edit_packet.c
@@ -117,6 +117,70 @@ fix_ipv6_checksums(tcpedit_t *tcpedit, struct pcap_pkthdr *pkthdr, ipv6_hdr_t *i
     return TCPEDIT_OK;
 }
 
+#define IP_DF       0x4000      /* Flag: "Don't Fragment"   */
+#define IP_MF       0x2000      /* Flag: "More Fragments"   */
+#define IP_OFFSET   0x1FFF      /* "Fragment Offset" part   */
+int chksum_replace_ipv4(tcpedit_t *tcpedit, ipv4_hdr_t *ip_hdr, u_int32_t from, u_int32_t to)
+{
+    if (tcpedit->fixcsum == TCPEDIT_FIXCSUM_DISABLE)
+        return 0;
+
+    chksum_replace4(&ip_hdr->ip_sum, from, to);
+    return 0;
+}
+
+static int transport_pseudo_chksum_ipv4(tcpedit_t *tcpedit, ipv4_hdr_t *ip_hdr,
+        u_int32_t from, u_int32_t to)
+{
+    int ihl;
+    u_char *transport;
+    u_int8_t protocol;
+
+    if (tcpedit->fixcsum == TCPEDIT_FIXCSUM_DISABLE)
+        return 0;
+
+    ihl = ip_hdr->ip_hl * 4;
+    transport = ((u_char *)ip_hdr) + ihl;
+    protocol = ip_hdr->ip_p;
+
+    chksum_replace4(&ip_hdr->ip_sum, from, to);
+
+    /* reject IP fragments */
+    if (ip_hdr->ip_off & htons(IP_OFFSET))
+        return 1;
+
+    switch (protocol) {
+    case IPPROTO_TCP:
+    {
+        struct tcpr_tcp_hdr *tcph;
+
+        tcph = (struct tcpr_tcp_hdr *)transport;
+        chksum_replace4(&tcph->th_sum, from, to);
+        break;
+    }
+    case IPPROTO_UDP:
+    {
+        struct tcpr_udp_hdr *udph;
+
+        udph = (struct tcpr_udp_hdr *)transport;
+        if (udph->uh_sum) {
+            chksum_replace4(&udph->uh_sum, from, to);
+            if (!udph->uh_sum)
+                udph->uh_sum = 0xffff; /* mangled checksum */
+        }
+        break;
+    }
+
+    case IPPROTO_ICMP:
+        break;
+
+    default:
+        return 1;
+    }
+
+    return 0;
+}
+
 /**
  * returns a new 32bit integer which is the randomized IP 
  * based upon the user specified seed
@@ -170,6 +234,8 @@ randomize_ipv4(tcpedit_t *tcpedit, struct pcap_pkthdr *pkthdr,
 #ifdef DEBUG
     char srcip[16], dstip[16];
 #endif
+    int needtorecalc = 0;
+
     assert(tcpedit);
     assert(pkthdr);
     assert(pktdata);
@@ -185,13 +251,17 @@ randomize_ipv4(tcpedit_t *tcpedit, struct pcap_pkthdr *pkthdr,
 
     /* don't rewrite broadcast addresses */
     if ((tcpedit->skip_broadcast && is_unicast_ipv4(tcpedit, (u_int32_t)ip_hdr->ip_dst.s_addr)) 
-        || !tcpedit->skip_broadcast) {
+            || !tcpedit->skip_broadcast) {
+        in_addr_t old_dst_ip = ip_hdr->ip_dst.s_addr;
         ip_hdr->ip_dst.s_addr = randomize_ipv4_addr(tcpedit, ip_hdr->ip_dst.s_addr);
+        needtorecalc += transport_pseudo_chksum_ipv4(tcpedit, ip_hdr, old_dst_ip, ip_hdr->ip_dst.s_addr);
     }
 
     if ((tcpedit->skip_broadcast && is_unicast_ipv4(tcpedit, (u_int32_t)ip_hdr->ip_src.s_addr))
-        || !tcpedit->skip_broadcast) {
+            || !tcpedit->skip_broadcast) {
+        in_addr_t old_src_ip = ip_hdr->ip_src.s_addr;
         ip_hdr->ip_src.s_addr = randomize_ipv4_addr(tcpedit, ip_hdr->ip_src.s_addr);
+        needtorecalc += transport_pseudo_chksum_ipv4(tcpedit, ip_hdr, old_src_ip, ip_hdr->ip_src.s_addr);
     }
 
 #ifdef DEBUG    
@@ -201,7 +271,7 @@ randomize_ipv4(tcpedit_t *tcpedit, struct pcap_pkthdr *pkthdr,
 
     dbgx(1, "New Src IP: %s\tNew Dst IP: %s\n", srcip, dstip);
 
-    return(1);
+    return(needtorecalc);
 }
 
 int

diff --git a/src/tcpedit/edit_packet.h b/src/tcpedit/edit_packet.h
@@ -67,6 +67,8 @@ int rewrite_ipv4_ttl(tcpedit_t *tcpedit, ipv4_hdr_t *ip_hdr);
 
 int rewrite_ipv6_hlim(tcpedit_t *tcpedit, ipv6_hdr_t *ip6_hdr);
 
+int chksum_replace_ipv4(tcpedit_t *tcpedit, ipv4_hdr_t *ip_hdr, u_int32_t from, u_int32_t to);
+
 #define BROADCAST_IP 4294967295
 
 #endif

diff --git a/src/tcpedit/tcpedit.c b/src/tcpedit/tcpedit.c
@@ -278,16 +278,19 @@ tcpedit_packet(tcpedit_t *tcpedit, struct pcap_pkthdr **pkthdr,
     if ((tcpedit->fixcsum == TCPEDIT_FIXCSUM_ON || 
             (needtorecalc && tcpedit->fixcsum != TCPEDIT_FIXCSUM_DISABLE))) {
         if (ip_hdr != NULL) {
+            dbgx(3, "doing IPv4 checksum: needtorecalc=%d", needtorecalc);
             retval = fix_ipv4_checksums(tcpedit, *pkthdr, ip_hdr);
         } else if (ip6_hdr != NULL) {
+            dbgx(3, "doing IPv6 checksum: needtorecalc=%d", needtorecalc);
             retval = fix_ipv6_checksums(tcpedit, *pkthdr, ip6_hdr);
         } else {
+            dbgx(3, "checksum not performed: needtorecalc=%d", needtorecalc);
             retval = TCPEDIT_OK;
         }
         if (retval < 0) {
             return TCPEDIT_ERROR;
         } else if (retval == TCPEDIT_WARN) {
-            warnx("%s", tcpedit_getwarn(tcpedit));
+            dbgx(3, "%s", tcpedit_getwarn(tcpedit));
         }
     }
 

diff --git a/src/tcpreplay.c b/src/tcpreplay.c
@@ -293,7 +293,7 @@ replay_file(int file_idx)
 
 
     if (pcap != NULL) {
-        dlt = sendpacket_get_dlt(options.intf1);
+        dlt = options.intf1dlt;
         if ((dlt > 0) && (dlt != pcap_datalink(pcap)))
             warnx("%s DLT (%s) does not match that of the outbound interface: %s (%s)", 
                 path, pcap_datalink_val_to_name(pcap_datalink(pcap)), 
@@ -606,7 +606,7 @@ post_args(int argc)
     if ((options.intf1 = sendpacket_open(options.intf1_name, ebuf, TCPR_DIR_C2S, sendpacket_type)) == NULL)
         errx(-1, "Can't open %s: %s", options.intf1_name, ebuf);
 
-    options.int1dlt = sendpacket_get_dlt(options.intf1);
+    options.intf1dlt = sendpacket_get_dlt(options.intf1);
 
     if (HAVE_OPT(INTF2)) {
         if (! HAVE_OPT(CACHEFILE) && ! HAVE_OPT(DUALFILE))
@@ -621,11 +621,11 @@ post_args(int argc)
         if ((options.intf2 = sendpacket_open(options.intf2_name, ebuf, TCPR_DIR_S2C, sendpacket_type)) == NULL)
             errx(-1, "Can't open %s: %s", options.intf2_name, ebuf);
 
-        options.int2dlt = sendpacket_get_dlt(options.intf2);
-        if (options.int2dlt != options.int1dlt)
+        options.intf2dlt = sendpacket_get_dlt(options.intf2);
+        if (options.intf2dlt != options.intf1dlt)
             errx(-1, "DLT type missmatch for %s (%s) and %s (%s)", 
-                    options.intf1_name, pcap_datalink_val_to_name(options.int1dlt),
-                    options.intf2_name, pcap_datalink_val_to_name(options.int2dlt));
+                    options.intf1_name, pcap_datalink_val_to_name(options.intf1dlt),
+                    options.intf2_name, pcap_datalink_val_to_name(options.intf2dlt));
     }
 
     if (HAVE_OPT(CACHEFILE)) {

diff --git a/src/tcpreplay.h b/src/tcpreplay.h
@@ -73,8 +73,8 @@ struct tcpreplay_opt_s {
     char *intf2_name;
     sendpacket_t *intf1;
     sendpacket_t *intf2;
-    int int1dlt;
-    int int2dlt;
+    int intf1dlt;
+    int intf2dlt;
 
 
     tcpr_speed_t speed;
-Original file line number
+Diff line change
@@ Expand Up / @@ -67,6 +67,8 @@ int rewrite_ipv4_ttl(tcpedit_t *tcpedit, ipv4_hdr_t *ip_hdr); @@
     int rewrite_ipv6_hlim(tcpedit_t *tcpedit, ipv6_hdr_t *ip6_hdr);
+    int chksum_replace_ipv4(tcpedit_t *tcpedit, ipv4_hdr_t *ip_hdr, u_int32_t from, u_int32_t to);
     #define BROADCAST_IP 4294967295
     #endif
@@ Expand Down @@