/*
- * This file implements decoding of ZeroMQ network protocol(s).
- *
- *
* Copyright (c) 2013 The TCPDUMP project
* All rights reserved.
*
* POSSIBILITY OF SUCH DAMAGE.
*/
-#ifdef HAVE_CONFIG_H
-#include "config.h"
-#endif
+/* \summary: ZeroMQ Message Transport Protocol (ZMTP) printer */
+/* specification: https://rfc.zeromq.org/spec/13/ */
-#include <netdissect-stdinc.h>
+#include <config.h>
+
+#include "netdissect-stdinc.h"
#include "netdissect.h"
#include "extract.h"
-static const char tstr[] = " [|zmtp1]";
/* Maximum number of ZMTP/1.0 frame body bytes (without the flags) to dump in
* hex and ASCII under a single "-v" flag.
*/
#define VBYTES 128
+static const struct tok flags_bm[] = {
+ { 0x01, "MORE" },
+ { 0x02, "R1" },
+ { 0x04, "R2" },
+ { 0x08, "R3" },
+ { 0x10, "R4" },
+ { 0x20, "R5" },
+ { 0x40, "R6" },
+ { 0x80, "R7" },
+ { 0, NULL }
+};
+
/*
* Below is an excerpt from the "13/ZMTP" specification:
*
uint64_t body_len_declared, body_len_captured, header_len;
uint8_t flags;
- ND_PRINT((ndo, "\n\t"));
- ND_TCHECK2(*cp, 1); /* length/0xFF */
+ ND_PRINT("\n\t");
- if (cp[0] != 0xFF) {
+ if (GET_U_1(cp) != 0xFF) { /* length/0xFF */
header_len = 1; /* length */
- body_len_declared = cp[0];
- ND_PRINT((ndo, " frame flags+body (8-bit) length %" PRIu64 "u", body_len_declared));
+ body_len_declared = GET_U_1(cp);
+ ND_PRINT(" frame flags+body (8-bit) length %" PRIu64, body_len_declared);
} else {
header_len = 1 + 8; /* 0xFF, length */
- ND_PRINT((ndo, " frame flags+body (64-bit) length"));
- ND_TCHECK2(*cp, header_len); /* 0xFF, length */
- body_len_declared = EXTRACT_64BITS(cp + 1);
- ND_PRINT((ndo, " %" PRIu64, body_len_declared));
+ ND_PRINT(" frame flags+body (64-bit) length");
+ ND_TCHECK_LEN(cp, header_len); /* 0xFF, length */
+ body_len_declared = GET_BE_U_8(cp + 1);
+ ND_PRINT(" %" PRIu64, body_len_declared);
}
if (body_len_declared == 0)
return cp + header_len; /* skip to the next frame */
- ND_TCHECK2(*cp, header_len + 1); /* ..., flags */
- flags = cp[header_len];
+ ND_TCHECK_LEN(cp, header_len + 1); /* ..., flags */
+ flags = GET_U_1(cp + header_len);
body_len_captured = ep - cp - header_len;
if (body_len_declared > body_len_captured)
- ND_PRINT((ndo, " (%" PRIu64 " captured)", body_len_captured));
- ND_PRINT((ndo, ", flags 0x%02x", flags));
+ ND_PRINT(" (%" PRIu64 " captured)", body_len_captured);
+ ND_PRINT(", flags 0x%02x", flags);
if (ndo->ndo_vflag) {
- uint64_t body_len_printed = min(body_len_captured, body_len_declared);
-
- ND_PRINT((ndo, " (%s|%s|%s|%s|%s|%s|%s|%s)",
- flags & 0x80 ? "MBZ" : "-",
- flags & 0x40 ? "MBZ" : "-",
- flags & 0x20 ? "MBZ" : "-",
- flags & 0x10 ? "MBZ" : "-",
- flags & 0x08 ? "MBZ" : "-",
- flags & 0x04 ? "MBZ" : "-",
- flags & 0x02 ? "MBZ" : "-",
- flags & 0x01 ? "MORE" : "-"));
+ uint64_t body_len_printed = ND_MIN(body_len_captured, body_len_declared);
+ ND_PRINT(" (%s)", bittok2str(flags_bm, "none", flags));
if (ndo->ndo_vflag == 1)
- body_len_printed = min(VBYTES + 1, body_len_printed);
+ body_len_printed = ND_MIN(VBYTES + 1, body_len_printed);
if (body_len_printed > 1) {
- ND_PRINT((ndo, ", first %" PRIu64 " byte(s) of body:", body_len_printed - 1));
+ ND_PRINT(", first %" PRIu64 " byte(s) of body:", body_len_printed - 1);
hex_and_ascii_print(ndo, "\n\t ", cp + header_len + 1, body_len_printed - 1);
- ND_PRINT((ndo, "\n"));
}
}
- ND_TCHECK2(*cp, header_len + body_len_declared); /* Next frame within the buffer ? */
- return cp + header_len + body_len_declared;
+ /*
+ * Do not advance cp by the sum of header_len and body_len_declared
+ * before each offset has successfully passed ND_TCHECK_LEN() as the
+ * sum can roll over (9 + 0xfffffffffffffff7 = 0) and cause an
+ * infinite loop.
+ */
+ cp += header_len;
+ ND_TCHECK_LEN(cp, body_len_declared); /* Next frame within the buffer ? */
+ return cp + body_len_declared;
trunc:
- ND_PRINT((ndo, "%s", tstr));
- return ep;
+ nd_trunc_longjmp(ndo);
}
void
zmtp1_print(netdissect_options *ndo, const u_char *cp, u_int len)
{
- const u_char *ep = min(ndo->ndo_snapend, cp + len);
+ const u_char *ep = ND_MIN(ndo->ndo_snapend, cp + len);
- ND_PRINT((ndo, ": ZMTP/1.0"));
+ ndo->ndo_protocol = "zmtp1";
+ ND_PRINT(": ZMTP/1.0");
while (cp < ep)
cp = zmtp1_print_frame(ndo, cp, ep);
}
zmtp1_print_intermediate_part(netdissect_options *ndo, const u_char *cp, const u_int len)
{
u_int frame_offset;
- uint64_t remaining_len;
+ u_int remaining_len;
- ND_TCHECK2(*cp, 2);
- frame_offset = EXTRACT_16BITS(cp);
- ND_PRINT((ndo, "\n\t frame offset 0x%04x", frame_offset));
+ frame_offset = GET_BE_U_2(cp);
+ ND_PRINT("\n\t frame offset 0x%04x", frame_offset);
cp += 2;
- remaining_len = ndo->ndo_snapend - cp; /* without the frame length */
+ remaining_len = ND_BYTES_AVAILABLE_AFTER(cp); /* without the frame length */
if (frame_offset == 0xFFFF)
frame_offset = len - 2; /* always within the declared length */
else if (2 + frame_offset > len) {
- ND_PRINT((ndo, " (exceeds datagram declared length)"));
+ ND_PRINT(" (exceeds datagram declared length)");
goto trunc;
}
/* offset within declared length of the datagram */
if (frame_offset) {
- ND_PRINT((ndo, "\n\t frame intermediate part, %u bytes", frame_offset));
+ ND_PRINT("\n\t frame intermediate part, %u bytes", frame_offset);
if (frame_offset > remaining_len)
- ND_PRINT((ndo, " (%"PRIu64" captured)", remaining_len));
+ ND_PRINT(" (%u captured)", remaining_len);
if (ndo->ndo_vflag) {
- uint64_t len_printed = min(frame_offset, remaining_len);
+ u_int len_printed = ND_MIN(frame_offset, remaining_len);
if (ndo->ndo_vflag == 1)
- len_printed = min(VBYTES, len_printed);
+ len_printed = ND_MIN(VBYTES, len_printed);
if (len_printed > 1) {
- ND_PRINT((ndo, ", first %"PRIu64" byte(s):", len_printed));
+ ND_PRINT(", first %u byte(s):", len_printed);
hex_and_ascii_print(ndo, "\n\t ", cp, len_printed);
- ND_PRINT((ndo, "\n"));
}
}
}
return cp + frame_offset;
trunc:
- ND_PRINT((ndo, "%s", tstr));
- return cp + len;
+ nd_trunc_longjmp(ndo);
}
void
-zmtp1_print_datagram(netdissect_options *ndo, const u_char *cp, const u_int len)
+zmtp1_datagram_print(netdissect_options *ndo, const u_char *cp, const u_int len)
{
- const u_char *ep = min(ndo->ndo_snapend, cp + len);
+ const u_char *ep = ND_MIN(ndo->ndo_snapend, cp + len);
+ ndo->ndo_protocol = "zmtp1";
cp = zmtp1_print_intermediate_part(ndo, cp, len);
while (cp < ep)
cp = zmtp1_print_frame(ndo, cp, ep);
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