| /* |
| * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997 |
| * The Regents of the University of California. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that: (1) source code distributions |
| * retain the above copyright notice and this paragraph in its entirety, (2) |
| * distributions including binary code include the above copyright notice and |
| * this paragraph in its entirety in the documentation or other materials |
| * provided with the distribution, and (3) all advertising materials mentioning |
| * features or use of this software display the following acknowledgement: |
| * ``This product includes software developed by the University of California, |
| * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of |
| * the University nor the names of its contributors may be used to endorse |
| * or promote products derived from this software without specific prior |
| * written permission. |
| * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED |
| * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF |
| * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. |
| * |
| * By Jeffrey Mogul/DECWRL |
| * loosely based on print-bootp.c |
| */ |
| |
| /* \summary: Network Time Protocol (NTP) printer */ |
| |
| /* |
| * specification: |
| * |
| * RFC 1119 - NTPv2 |
| * RFC 1305 - NTPv3 |
| * RFC 5905 - NTPv4 |
| */ |
| |
| #ifdef HAVE_CONFIG_H |
| #include <config.h> |
| #endif |
| |
| #include "netdissect-stdinc.h" |
| |
| #include <time.h> |
| |
| #include "netdissect.h" |
| #include "addrtoname.h" |
| #include "extract.h" |
| |
| #include "ntp.h" |
| |
| /* |
| * Based on ntp.h from the U of MD implementation |
| * This file is based on Version 2 of the NTP spec (RFC1119). |
| */ |
| |
| /* rfc2030 |
| * 1 2 3 |
| * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * |LI | VN |Mode | Stratum | Poll | Precision | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | Root Delay | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | Root Dispersion | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | Reference Identifier | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | | |
| * | Reference Timestamp (64) | |
| * | | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | | |
| * | Originate Timestamp (64) | |
| * | | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | | |
| * | Receive Timestamp (64) | |
| * | | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | | |
| * | Transmit Timestamp (64) | |
| * | | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | Key Identifier (optional) (32) | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | | |
| * | | |
| * | Message Digest (optional) (128) | |
| * | | |
| * | | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| */ |
| |
| /* Length of the NTP data message with the mandatory fields ("the header") |
| * and without any optional fields (extension, Key Identifier, |
| * Message Digest). |
| */ |
| #define NTP_TIMEMSG_MINLEN 48U |
| |
| struct ntp_time_data { |
| nd_uint8_t status; /* status of local clock and leap info */ |
| nd_uint8_t stratum; /* Stratum level */ |
| nd_int8_t ppoll; /* poll value */ |
| nd_int8_t precision; |
| struct s_fixedpt root_delay; |
| struct s_fixedpt root_dispersion; |
| nd_uint32_t refid; |
| struct l_fixedpt ref_timestamp; |
| struct l_fixedpt org_timestamp; |
| struct l_fixedpt rec_timestamp; |
| struct l_fixedpt xmt_timestamp; |
| nd_uint32_t key_id; |
| nd_uint8_t message_digest[20]; |
| }; |
| /* |
| * Leap Second Codes (high order two bits) |
| */ |
| #define NO_WARNING 0x00 /* no warning */ |
| #define PLUS_SEC 0x40 /* add a second (61 seconds) */ |
| #define MINUS_SEC 0x80 /* minus a second (59 seconds) */ |
| #define ALARM 0xc0 /* alarm condition (clock unsynchronized) */ |
| |
| /* |
| * Clock Status Bits that Encode Version |
| */ |
| #define NTPVERSION_1 0x08 |
| #define VERSIONMASK 0x38 |
| #define VERSIONSHIFT 3 |
| #define LEAPMASK 0xc0 |
| #define LEAPSHIFT 6 |
| #ifdef MODEMASK |
| #undef MODEMASK /* Solaris sucks */ |
| #endif |
| #define MODEMASK 0x07 |
| #define MODESHIFT 0 |
| |
| /* |
| * Code values |
| */ |
| #define MODE_UNSPEC 0 /* unspecified */ |
| #define MODE_SYM_ACT 1 /* symmetric active */ |
| #define MODE_SYM_PAS 2 /* symmetric passive */ |
| #define MODE_CLIENT 3 /* client */ |
| #define MODE_SERVER 4 /* server */ |
| #define MODE_BROADCAST 5 /* broadcast */ |
| #define MODE_CONTROL 6 /* control message */ |
| #define MODE_RES2 7 /* reserved */ |
| |
| /* |
| * Stratum Definitions |
| */ |
| #define UNSPECIFIED 0 |
| #define PRIM_REF 1 /* radio clock */ |
| #define INFO_QUERY 62 /* **** THIS implementation dependent **** */ |
| #define INFO_REPLY 63 /* **** THIS implementation dependent **** */ |
| |
| static void p_sfix(netdissect_options *ndo, const struct s_fixedpt *); |
| static void p_ntp_delta(netdissect_options *, const struct l_fixedpt *, const struct l_fixedpt *); |
| static void p_poll(netdissect_options *, const int); |
| |
| static const struct tok ntp_mode_values[] = { |
| { MODE_UNSPEC, "unspecified" }, |
| { MODE_SYM_ACT, "symmetric active" }, |
| { MODE_SYM_PAS, "symmetric passive" }, |
| { MODE_CLIENT, "Client" }, |
| { MODE_SERVER, "Server" }, |
| { MODE_BROADCAST, "Broadcast" }, |
| { MODE_CONTROL, "Control Message" }, |
| { MODE_RES2, "Reserved" }, |
| { 0, NULL } |
| }; |
| |
| static const struct tok ntp_leapind_values[] = { |
| { NO_WARNING, "" }, |
| { PLUS_SEC, "+1s" }, |
| { MINUS_SEC, "-1s" }, |
| { ALARM, "clock unsynchronized" }, |
| { 0, NULL } |
| }; |
| |
| static const struct tok ntp_stratum_values[] = { |
| { UNSPECIFIED, "unspecified" }, |
| { PRIM_REF, "primary reference" }, |
| { 0, NULL } |
| }; |
| |
| /* draft-ietf-ntp-mode-6-cmds-02 |
| * 0 1 2 3 |
| * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * |LI | VN |Mode |R|E|M| OpCode | Sequence Number | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | Status | Association ID | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | Offset | Count | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | | |
| * / Data (up to 468 bytes) / |
| * | | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | Padding (optional) | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | | |
| * / Authenticator (optional, 96 bytes) / |
| * | | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * |
| * Figure 1: NTP Control Message Header |
| */ |
| |
| /* Length of the NTP control message with the mandatory fields ("the header") |
| * and without any optional fields (Data, Padding, Authenticator). |
| */ |
| #define NTP_CTRLMSG_MINLEN 12U |
| |
| struct ntp_control_data { |
| nd_uint8_t magic; /* LI, VN, Mode */ |
| nd_uint8_t control; /* R, E, M, OpCode */ |
| nd_uint16_t sequence; /* Sequence Number */ |
| nd_uint16_t status; /* Status */ |
| nd_uint16_t assoc; /* Association ID */ |
| nd_uint16_t offset; /* Offset */ |
| nd_uint16_t count; /* Count */ |
| nd_uint8_t data[564]; /* Data, [Padding, [Authenticator]] */ |
| }; |
| |
| /* |
| * Print NTP time requests and responses |
| */ |
| static void |
| ntp_time_print(netdissect_options *ndo, |
| const struct ntp_time_data *bp, u_int length) |
| { |
| uint8_t stratum; |
| |
| if (length < NTP_TIMEMSG_MINLEN) |
| goto invalid; |
| |
| stratum = GET_U_1(bp->stratum); |
| ND_PRINT(", Stratum %u (%s)", |
| stratum, |
| tok2str(ntp_stratum_values, (stratum >=2 && stratum<=15) ? "secondary reference" : "reserved", stratum)); |
| |
| ND_PRINT(", poll %d", GET_S_1(bp->ppoll)); |
| p_poll(ndo, GET_S_1(bp->ppoll)); |
| |
| ND_PRINT(", precision %d", GET_S_1(bp->precision)); |
| |
| ND_TCHECK_SIZE(&bp->root_delay); |
| ND_PRINT("\n\tRoot Delay: "); |
| p_sfix(ndo, &bp->root_delay); |
| |
| ND_TCHECK_SIZE(&bp->root_dispersion); |
| ND_PRINT(", Root dispersion: "); |
| p_sfix(ndo, &bp->root_dispersion); |
| |
| ND_TCHECK_4(bp->refid); |
| ND_PRINT(", Reference-ID: "); |
| /* Interpretation depends on stratum */ |
| switch (stratum) { |
| |
| case UNSPECIFIED: |
| ND_PRINT("(unspec)"); |
| break; |
| |
| case PRIM_REF: |
| if (nd_printn(ndo, (const u_char *)&(bp->refid), 4, ndo->ndo_snapend)) |
| goto trunc; |
| break; |
| |
| case INFO_QUERY: |
| ND_PRINT("%s INFO_QUERY", GET_IPADDR_STRING(bp->refid)); |
| /* this doesn't have more content */ |
| return; |
| |
| case INFO_REPLY: |
| ND_PRINT("%s INFO_REPLY", GET_IPADDR_STRING(bp->refid)); |
| /* this is too complex to be worth printing */ |
| return; |
| |
| default: |
| /* In NTPv4 (RFC 5905) refid is an IPv4 address or first 32 bits of |
| MD5 sum of IPv6 address */ |
| ND_PRINT("0x%08x", GET_BE_U_4(bp->refid)); |
| break; |
| } |
| |
| ND_TCHECK_SIZE(&bp->ref_timestamp); |
| ND_PRINT("\n\t Reference Timestamp: "); |
| p_ntp_time(ndo, &(bp->ref_timestamp)); |
| |
| ND_TCHECK_SIZE(&bp->org_timestamp); |
| ND_PRINT("\n\t Originator Timestamp: "); |
| p_ntp_time(ndo, &(bp->org_timestamp)); |
| |
| ND_TCHECK_SIZE(&bp->rec_timestamp); |
| ND_PRINT("\n\t Receive Timestamp: "); |
| p_ntp_time(ndo, &(bp->rec_timestamp)); |
| |
| ND_TCHECK_SIZE(&bp->xmt_timestamp); |
| ND_PRINT("\n\t Transmit Timestamp: "); |
| p_ntp_time(ndo, &(bp->xmt_timestamp)); |
| |
| ND_PRINT("\n\t Originator - Receive Timestamp: "); |
| p_ntp_delta(ndo, &(bp->org_timestamp), &(bp->rec_timestamp)); |
| |
| ND_PRINT("\n\t Originator - Transmit Timestamp: "); |
| p_ntp_delta(ndo, &(bp->org_timestamp), &(bp->xmt_timestamp)); |
| |
| /* FIXME: this code is not aware of any extension fields */ |
| if (length == NTP_TIMEMSG_MINLEN + 4) { /* Optional: key-id (crypto-NAK) */ |
| ND_PRINT("\n\tKey id: %u", GET_BE_U_4(bp->key_id)); |
| } else if (length == NTP_TIMEMSG_MINLEN + 4 + 16) { /* Optional: key-id + 128-bit digest */ |
| ND_PRINT("\n\tKey id: %u", GET_BE_U_4(bp->key_id)); |
| ND_TCHECK_LEN(bp->message_digest, 16); |
| ND_PRINT("\n\tAuthentication: %08x%08x%08x%08x", |
| GET_BE_U_4(bp->message_digest), |
| GET_BE_U_4(bp->message_digest + 4), |
| GET_BE_U_4(bp->message_digest + 8), |
| GET_BE_U_4(bp->message_digest + 12)); |
| } else if (length == NTP_TIMEMSG_MINLEN + 4 + 20) { /* Optional: key-id + 160-bit digest */ |
| ND_PRINT("\n\tKey id: %u", GET_BE_U_4(bp->key_id)); |
| ND_TCHECK_LEN(bp->message_digest, 20); |
| ND_PRINT("\n\tAuthentication: %08x%08x%08x%08x%08x", |
| GET_BE_U_4(bp->message_digest), |
| GET_BE_U_4(bp->message_digest + 4), |
| GET_BE_U_4(bp->message_digest + 8), |
| GET_BE_U_4(bp->message_digest + 12), |
| GET_BE_U_4(bp->message_digest + 16)); |
| } else if (length > NTP_TIMEMSG_MINLEN) { |
| ND_PRINT("\n\t(%u more bytes after the header)", length - NTP_TIMEMSG_MINLEN); |
| } |
| return; |
| |
| invalid: |
| nd_print_invalid(ndo); |
| ND_TCHECK_LEN(bp, length); |
| return; |
| |
| trunc: |
| nd_print_trunc(ndo); |
| } |
| |
| /* |
| * Print NTP control message requests and responses |
| */ |
| static void |
| ntp_control_print(netdissect_options *ndo, |
| const struct ntp_control_data *cd, u_int length) |
| { |
| uint8_t control, R, E, M, opcode; |
| uint16_t sequence, status, assoc, offset, count; |
| |
| if (length < NTP_CTRLMSG_MINLEN) |
| goto invalid; |
| |
| control = GET_U_1(cd->control); |
| R = (control & 0x80) != 0; |
| E = (control & 0x40) != 0; |
| M = (control & 0x20) != 0; |
| opcode = control & 0x1f; |
| ND_PRINT(", %s, %s, %s, OpCode=%u\n", |
| R ? "Response" : "Request", E ? "Error" : "OK", |
| M ? "More" : "Last", opcode); |
| |
| sequence = GET_BE_U_2(cd->sequence); |
| ND_PRINT("\tSequence=%hu", sequence); |
| |
| status = GET_BE_U_2(cd->status); |
| ND_PRINT(", Status=%#hx", status); |
| |
| assoc = GET_BE_U_2(cd->assoc); |
| ND_PRINT(", Assoc.=%hu", assoc); |
| |
| offset = GET_BE_U_2(cd->offset); |
| ND_PRINT(", Offset=%hu", offset); |
| |
| count = GET_BE_U_2(cd->count); |
| ND_PRINT(", Count=%hu", count); |
| |
| if (NTP_CTRLMSG_MINLEN + count > length) |
| goto invalid; |
| if (count != 0) { |
| ND_TCHECK_LEN(cd->data, count); |
| ND_PRINT("\n\tTO-BE-DONE: data not interpreted"); |
| } |
| return; |
| |
| invalid: |
| nd_print_invalid(ndo); |
| ND_TCHECK_LEN(cd, length); |
| return; |
| |
| trunc: |
| nd_print_trunc(ndo); |
| } |
| |
| union ntpdata { |
| struct ntp_time_data td; |
| struct ntp_control_data cd; |
| }; |
| |
| /* |
| * Print NTP requests, handling the common VN, LI, and Mode |
| */ |
| void |
| ntp_print(netdissect_options *ndo, |
| const u_char *cp, u_int length) |
| { |
| const union ntpdata *bp = (const union ntpdata *)cp; |
| u_int mode, version, leapind; |
| uint8_t status; |
| |
| ndo->ndo_protocol = "ntp"; |
| status = GET_U_1(bp->td.status); |
| |
| version = (status & VERSIONMASK) >> VERSIONSHIFT; |
| ND_PRINT("NTPv%u", version); |
| |
| mode = (status & MODEMASK) >> MODESHIFT; |
| if (!ndo->ndo_vflag) { |
| ND_PRINT(", %s, length %u", |
| tok2str(ntp_mode_values, "Unknown mode", mode), |
| length); |
| return; |
| } |
| |
| ND_PRINT(", %s, length %u\n", |
| tok2str(ntp_mode_values, "Unknown mode", mode), length); |
| |
| /* leapind = (status & LEAPMASK) >> LEAPSHIFT; */ |
| leapind = (status & LEAPMASK); |
| ND_PRINT("\tLeap indicator: %s (%u)", |
| tok2str(ntp_leapind_values, "Unknown", leapind), |
| leapind); |
| |
| switch (mode) { |
| |
| case MODE_UNSPEC: |
| case MODE_SYM_ACT: |
| case MODE_SYM_PAS: |
| case MODE_CLIENT: |
| case MODE_SERVER: |
| case MODE_BROADCAST: |
| ntp_time_print(ndo, &bp->td, length); |
| break; |
| |
| case MODE_CONTROL: |
| ntp_control_print(ndo, &bp->cd, length); |
| break; |
| |
| default: |
| break; /* XXX: not implemented! */ |
| } |
| } |
| |
| static void |
| p_sfix(netdissect_options *ndo, |
| const struct s_fixedpt *sfp) |
| { |
| int i; |
| int f; |
| double ff; |
| |
| i = GET_BE_U_2(sfp->int_part); |
| f = GET_BE_U_2(sfp->fraction); |
| ff = f / 65536.0; /* shift radix point by 16 bits */ |
| f = (int)(ff * 1000000.0); /* Treat fraction as parts per million */ |
| ND_PRINT("%d.%06d", i, f); |
| } |
| |
| /* Prints time difference between *lfp and *olfp */ |
| static void |
| p_ntp_delta(netdissect_options *ndo, |
| const struct l_fixedpt *olfp, |
| const struct l_fixedpt *lfp) |
| { |
| uint32_t u, uf; |
| uint32_t ou, ouf; |
| uint32_t i; |
| uint32_t f; |
| double ff; |
| int signbit; |
| |
| u = GET_BE_U_4(lfp->int_part); |
| ou = GET_BE_U_4(olfp->int_part); |
| uf = GET_BE_U_4(lfp->fraction); |
| ouf = GET_BE_U_4(olfp->fraction); |
| if (ou == 0 && ouf == 0) { |
| p_ntp_time(ndo, lfp); |
| return; |
| } |
| |
| if (u > ou) { /* new is definitely greater than old */ |
| signbit = 0; |
| i = u - ou; |
| f = uf - ouf; |
| if (ouf > uf) /* must borrow from high-order bits */ |
| i -= 1; |
| } else if (u < ou) { /* new is definitely less than old */ |
| signbit = 1; |
| i = ou - u; |
| f = ouf - uf; |
| if (uf > ouf) /* must borrow from the high-order bits */ |
| i -= 1; |
| } else { /* int_part is zero */ |
| i = 0; |
| if (uf > ouf) { |
| signbit = 0; |
| f = uf - ouf; |
| } else { |
| signbit = 1; |
| f = ouf - uf; |
| } |
| } |
| |
| ff = f; |
| if (ff < 0.0) /* some compilers are buggy */ |
| ff += FMAXINT; |
| ff = ff / FMAXINT; /* shift radix point by 32 bits */ |
| f = (uint32_t)(ff * 1000000000.0); /* treat fraction as parts per billion */ |
| ND_PRINT("%s%u.%09u", signbit ? "-" : "+", i, f); |
| } |
| |
| /* Prints polling interval in log2 as seconds or fraction of second */ |
| static void |
| p_poll(netdissect_options *ndo, |
| const int poll_interval) |
| { |
| if (poll_interval <= -32 || poll_interval >= 32) |
| return; |
| |
| if (poll_interval >= 0) |
| ND_PRINT(" (%us)", 1U << poll_interval); |
| else |
| ND_PRINT(" (1/%us)", 1U << -poll_interval); |
| } |
| |
