print-zeromq.c revision 251127
10SN/A/* 210346SN/A * This file implements decoding of ZeroMQ network protocol(s). 30SN/A * 40SN/A * 50SN/A * Copyright (c) 2013 The TCPDUMP project 60SN/A * All rights reserved. 72362SN/A * 80SN/A * Redistribution and use in source and binary forms, with or without 92362SN/A * modification, are permitted provided that the following conditions 100SN/A * are met: 110SN/A * 1. Redistributions of source code must retain the above copyright 120SN/A * notice, this list of conditions and the following disclaimer. 130SN/A * 2. Redistributions in binary form must reproduce the above copyright 140SN/A * notice, this list of conditions and the following disclaimer in the 150SN/A * documentation and/or other materials provided with the distribution. 160SN/A * 170SN/A * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 180SN/A * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 190SN/A * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 200SN/A * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 212362SN/A * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 222362SN/A * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 232362SN/A * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 240SN/A * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 250SN/A * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 260SN/A * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 270SN/A * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 280SN/A * POSSIBILITY OF SUCH DAMAGE. 290SN/A */ 300SN/A 310SN/A#ifdef HAVE_CONFIG_H 320SN/A#include "config.h" 330SN/A#endif 340SN/A 350SN/A#include <tcpdump-stdinc.h> 360SN/A 370SN/A#include <stdio.h> 380SN/A 390SN/A#include "interface.h" 400SN/A#include "extract.h" 410SN/A 420SN/A/* Maximum number of ZMTP/1.0 frame body bytes (without the flags) to dump in 430SN/A * hex and ASCII under a single "-v" flag. 440SN/A */ 450SN/A#define VBYTES 128 460SN/A 470SN/A/* 480SN/A * Below is an excerpt from the "13/ZMTP" specification: 490SN/A * 500SN/A * A ZMTP message consists of 1 or more frames. 510SN/A * 520SN/A * A ZMTP frame consists of a length, followed by a flags field and a frame 530SN/A * body of (length - 1) octets. Note: the length includes the flags field, so 540SN/A * an empty frame has a length of 1. 550SN/A * 560SN/A * For frames with a length of 1 to 254 octets, the length SHOULD BE encoded 570SN/A * as a single octet. The minimum valid length of a frame is 1 octet, thus a 580SN/A * length of 0 is invalid and such frames SHOULD be discarded silently. 590SN/A * 600SN/A * For frames with lengths of 255 and greater, the length SHALL BE encoded as 610SN/A * a single octet with the value 255, followed by the length encoded as a 620SN/A * 64-bit unsigned integer in network byte order. For frames with lengths of 630SN/A * 1 to 254 octets this encoding MAY be also used. 640SN/A * 650SN/A * The flags field consists of a single octet containing various control 660SN/A * flags. Bit 0 is the least significant bit. 670SN/A * 680SN/A * - Bit 0 (MORE): More frames to follow. A value of 0 indicates that there 690SN/A * are no more frames to follow. A value of 1 indicates that more frames 700SN/A * will follow. On messages consisting of a single frame the MORE flag MUST 710SN/A * be 0. 720SN/A * 7312195Savstepan * - Bits 1-7: Reserved. Bits 1-7 are reserved for future use and SHOULD be 740SN/A * zero. 750SN/A */ 760SN/A 770SN/Astatic const u_char * 780SN/Azmtp1_print_frame(const u_char *cp, const u_char *ep) { 790SN/A u_int64_t body_len_declared, body_len_captured, header_len; 800SN/A u_int8_t flags; 810SN/A 820SN/A printf("\n\t"); 830SN/A TCHECK2(*cp, 1); /* length/0xFF */ 840SN/A 850SN/A if (cp[0] != 0xFF) { 860SN/A header_len = 1; /* length */ 870SN/A body_len_declared = cp[0]; 880SN/A if (body_len_declared == 0) 890SN/A return cp + header_len; /* skip to next frame */ 900SN/A printf(" frame flags+body (8-bit) length %"PRIu8"", cp[0]); 910SN/A TCHECK2(*cp, header_len + 1); /* length, flags */ 920SN/A flags = cp[1]; 930SN/A } else { 940SN/A header_len = 1 + 8; /* 0xFF, length */ 950SN/A printf(" frame flags+body (64-bit) length"); 960SN/A TCHECK2(*cp, header_len); /* 0xFF, length */ 970SN/A body_len_declared = EXTRACT_64BITS(cp + 1); 980SN/A if (body_len_declared == 0) 990SN/A return cp + header_len; /* skip to next frame */ 1000SN/A printf(" %"PRIu64"", body_len_declared); 1010SN/A TCHECK2(*cp, header_len + 1); /* 0xFF, length, flags */ 1020SN/A flags = cp[9]; 1030SN/A } 1040SN/A 1050SN/A body_len_captured = ep - cp - header_len; 1060SN/A if (body_len_declared > body_len_captured) 1070SN/A printf(" (%"PRIu64" captured)", body_len_captured); 1080SN/A printf(", flags 0x%02"PRIx8"", flags); 1090SN/A 1100SN/A if (vflag) { 11110346SN/A u_int64_t body_len_printed = MIN(body_len_captured, body_len_declared); 11210346SN/A 11310346SN/A printf(" (%s|%s|%s|%s|%s|%s|%s|%s)", 1140SN/A flags & 0x80 ? "MBZ" : "-", 1150SN/A flags & 0x40 ? "MBZ" : "-", 1160SN/A flags & 0x20 ? "MBZ" : "-", 1170SN/A flags & 0x10 ? "MBZ" : "-", 1180SN/A flags & 0x08 ? "MBZ" : "-", 1190SN/A flags & 0x04 ? "MBZ" : "-", 1200SN/A flags & 0x02 ? "MBZ" : "-", 1210SN/A flags & 0x01 ? "MORE" : "-"); 1220SN/A 1230SN/A if (vflag == 1) 1240SN/A body_len_printed = MIN(VBYTES + 1, body_len_printed); 1250SN/A if (body_len_printed > 1) { 1260SN/A printf(", first %"PRIu64" byte(s) of body:", body_len_printed - 1); 1270SN/A hex_and_ascii_print("\n\t ", cp + header_len + 1, body_len_printed - 1); 1280SN/A printf("\n"); 1290SN/A } 1300SN/A } 1310SN/A 1320SN/A TCHECK2(*cp, header_len + body_len_declared); /* Next frame within the buffer ? */ 1330SN/A return cp + header_len + body_len_declared; 1340SN/A 1350SN/Atrunc: 1360SN/A printf(" [|zmtp1]"); 1370SN/A return ep; 1380SN/A} 1390SN/A 1400SN/Avoid 1410SN/Azmtp1_print(const u_char *cp, u_int len) { 1420SN/A const u_char *ep = MIN(snapend, cp + len); 1430SN/A 1440SN/A printf(": ZMTP/1.0"); 1450SN/A while (cp < ep) 1460SN/A cp = zmtp1_print_frame(cp, ep); 1470SN/A} 1480SN/A 1490SN/A