From: Ethan Jackson Date: Wed, 21 Dec 2011 20:59:28 +0000 (-0800) Subject: ofp-print: Remove tcpdump from ofp_packet_to_string(). X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=897a8e0791171c8cb71e27c31d159a08205e5741;p=openvswitch ofp-print: Remove tcpdump from ofp_packet_to_string(). Instead this patch uses flow_format() which gives very similar output. This patch will improve the reliability of unit tests in future patches which rely on the results of ofp_packet_to_string(). Signed-off-by: Ethan Jackson --- diff --git a/INSTALL.Linux b/INSTALL.Linux index 7a55ccd1..8ef23157 100644 --- a/INSTALL.Linux +++ b/INSTALL.Linux @@ -117,11 +117,6 @@ following software: iproute2 (part of all major distributions and available at http://www.linux-foundation.org/en/Net:Iproute2). - - For debugging purposes, Open vSwitch expects that "tcpdump" is - installed as /usr/sbin/tcpdump. If tcpdump is not installed, or - if it is installed in a different location, then some Open - vSwitch log messages will not be as detailed. - You should ensure that /dev/urandom exists. To support TAP devices, you must also ensure that /dev/net/tun exists. diff --git a/lib/ofp-print.c b/lib/ofp-print.c index 7ed3ce12..fe4af4c8 100644 --- a/lib/ofp-print.c +++ b/lib/ofp-print.c @@ -49,58 +49,19 @@ static void ofp_print_error(struct ds *, int error); /* Returns a string that represents the contents of the Ethernet frame in the - * 'len' bytes starting at 'data' to 'stream' as output by tcpdump. - * - * The caller must free the returned string. - * - * This starts and kills a tcpdump subprocess so it's quite expensive. */ + * 'len' bytes starting at 'data'. The caller must free the returned string.*/ char * ofp_packet_to_string(const void *data, size_t len) { struct ds ds = DS_EMPTY_INITIALIZER; struct ofpbuf buf; - - char command[128]; - FILE *pcap; - FILE *tcpdump; - int status; - int c; + struct flow flow; ofpbuf_use_const(&buf, data, len); + flow_extract(&buf, 0, 0, 0, &flow); + flow_format(&ds, &flow); + ds_put_char(&ds, '\n'); - pcap = tmpfile(); - if (!pcap) { - ovs_error(errno, "tmpfile"); - return xstrdup(""); - } - pcap_write_header(pcap); - pcap_write(pcap, &buf); - fflush(pcap); - if (ferror(pcap)) { - ovs_error(errno, "error writing temporary file"); - } - rewind(pcap); - - snprintf(command, sizeof command, "/usr/sbin/tcpdump -t -e -n -r /dev/fd/%d 2>/dev/null", - fileno(pcap)); - tcpdump = popen(command, "r"); - fclose(pcap); - if (!tcpdump) { - ovs_error(errno, "exec(\"%s\")", command); - return xstrdup(""); - } - - while ((c = getc(tcpdump)) != EOF) { - ds_put_char(&ds, c); - } - - status = pclose(tcpdump); - if (WIFEXITED(status)) { - if (WEXITSTATUS(status)) - ovs_error(0, "tcpdump exited with status %d", WEXITSTATUS(status)); - } else if (WIFSIGNALED(status)) { - ovs_error(0, "tcpdump exited with signal %d", WTERMSIG(status)); - } return ds_cstr(&ds); } @@ -134,15 +95,6 @@ ofp_print_packet_in(struct ds *string, const struct ofp_packet_in *op, ds_put_char(string, '\n'); if (verbosity > 0) { - struct flow flow; - struct ofpbuf packet; - - ofpbuf_use_const(&packet, op->data, data_len); - flow_extract(&packet, 0, 0, ntohs(op->in_port), &flow); - flow_format(string, &flow); - ds_put_char(string, '\n'); - } - if (verbosity > 1) { char *packet = ofp_packet_to_string(op->data, data_len); ds_put_cstr(string, packet); free(packet); @@ -1589,10 +1541,7 @@ ofp_print(FILE *stream, const void *oh, size_t len, int verbosity) } /* Dumps the contents of the Ethernet frame in the 'len' bytes starting at - * 'data' to 'stream' using tcpdump. 'total_len' specifies the full length of - * the Ethernet frame (of which 'len' bytes were captured). - * - * This starts and kills a tcpdump subprocess so it's quite expensive. */ + * 'data' to 'stream'. */ void ofp_print_packet(FILE *stream, const void *data, size_t len) { diff --git a/tests/ofp-print.at b/tests/ofp-print.at index 09b785bc..5734174d 100644 --- a/tests/ofp-print.at +++ b/tests/ofp-print.at @@ -225,20 +225,15 @@ AT_CLEANUP AT_SETUP([OFPT_PACKET_IN]) AT_KEYWORDS([ofp-print]) -AT_SKIP_IF([test ! -x /usr/sbin/tcpdump]) AT_CHECK([ovs-ofctl ofp-print "\ 01 0a 00 4e 00 00 00 00 00 00 01 11 00 3c 00 03 \ 00 00 50 54 00 00 00 06 50 54 00 00 00 05 08 00 \ 45 00 00 28 bd 12 00 00 40 06 3c 6a c0 a8 00 01 \ c0 a8 00 02 27 2f 00 00 78 50 cc 5b 57 af 42 1e \ 50 00 02 00 26 e8 00 00 00 00 00 00 00 00 \ -"], [0], [stdout]) -dnl The tcpdump output format differs slightly from one version to another, -dnl so trim off the end of the line where differences appear. -AT_CHECK([sed 's/\(length 60:\).*/\1 .../' stdout], [0], [dnl +"], [0], [dnl OFPT_PACKET_IN (xid=0x0): total_len=60 in_port=3 data_len=60 buffer=0x00000111 -priority:0,tunnel:0,in_port:0003,tci(0) mac(50:54:00:00:00:05->50:54:00:00:00:06) type:0800 proto:6 tos:0 ttl:64 ip(192.168.0.1->192.168.0.2) port(10031->0) -50:54:00:00:00:05 > 50:54:00:00:00:06, ethertype IPv4 (0x0800), length 60: ... +priority:0,tunnel:0,in_port:0000,tci(0) mac(50:54:00:00:00:05->50:54:00:00:00:06) type:0800 proto:6 tos:0 ttl:64 ip(192.168.0.1->192.168.0.2) port(10031->0) ]) AT_CLEANUP