├── .gitignore ├── LICENSE ├── Makefile ├── README.md ├── ntpproxy.c └── sls.c /.gitignore: -------------------------------------------------------------------------------- 1 | /sls 2 | /ntpproxy 3 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | GNU GENERAL PUBLIC LICENSE 2 | Version 3, 29 June 2007 3 | 4 | Copyright (C) 2007 Free Software Foundation, Inc. 5 | Everyone is permitted to copy and distribute verbatim copies 6 | of this license document, but changing it is not allowed. 7 | 8 | Preamble 9 | 10 | The GNU General Public License is a free, copyleft license for 11 | software and other kinds of works. 12 | 13 | The licenses for most software and other practical works are designed 14 | to take away your freedom to share and change the works. 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It is safest 630 | to attach them to the start of each source file to most effectively 631 | state the exclusion of warranty; and each file should have at least 632 | the "copyright" line and a pointer to where the full notice is found. 633 | 634 | 635 | Copyright (C) 636 | 637 | This program is free software: you can redistribute it and/or modify 638 | it under the terms of the GNU General Public License as published by 639 | the Free Software Foundation, either version 3 of the License, or 640 | (at your option) any later version. 641 | 642 | This program is distributed in the hope that it will be useful, 643 | but WITHOUT ANY WARRANTY; without even the implied warranty of 644 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 645 | GNU General Public License for more details. 646 | 647 | You should have received a copy of the GNU General Public License 648 | along with this program. If not, see . 649 | 650 | Also add information on how to contact you by electronic and paper mail. 651 | 652 | If the program does terminal interaction, make it output a short 653 | notice like this when it starts in an interactive mode: 654 | 655 | Copyright (C) 656 | This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. 657 | This is free software, and you are welcome to redistribute it 658 | under certain conditions; type `show c' for details. 659 | 660 | The hypothetical commands `show w' and `show c' should show the appropriate 661 | parts of the General Public License. Of course, your program's commands 662 | might be different; for a GUI interface, you would use an "about box". 663 | 664 | You should also get your employer (if you work as a programmer) or school, 665 | if any, to sign a "copyright disclaimer" for the program, if necessary. 666 | For more information on this, and how to apply and follow the GNU GPL, see 667 | . 668 | 669 | The GNU General Public License does not permit incorporating your program 670 | into proprietary programs. If your program is a subroutine library, you 671 | may consider it more useful to permit linking proprietary applications with 672 | the library. If this is what you want to do, use the GNU Lesser General 673 | Public License instead of this License. But first, please read 674 | . 675 | -------------------------------------------------------------------------------- /Makefile: -------------------------------------------------------------------------------- 1 | BINARIES=sls ntpproxy 2 | 3 | .PHONY: clean 4 | 5 | all: $(BINARIES) 6 | 7 | clean: 8 | $(RM) $(BINARIES) 9 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # Leap Second Test tool 2 | 3 | Latest update: 01 May 2015 4 | 5 | Initial release: [Robert Karbowski](mailto:rkarbowski@amadeus.com) 6 | 7 | ## Table of Contents 8 | 9 | - [Introduction](#introduction) 10 | - [NTP and leap second](#ntp-and-leap-second) 11 | - [Compilation](#compilation) 12 | - [Leap second test bed](#leap-second-test-bed) 13 | - [Direct LS simulation](#direct-ls-simulation) 14 | - [Environment setup](#environment-setup) 15 | - [Indirect LS simulation via NTP](#indirect-ls-simulation-via-ntp) 16 | - [Environment setup](#environment-setup-1) 17 | - [Useful links](#useful-links) 18 | 19 | ## Introduction 20 | 21 | Leap Second Test tool consists of two programs which can be used 22 | for OS/application leap second immunity verification. 23 | * Set Leap Second - local leap second simulation - only for Linux 24 | * NTP Proxy - indirect leap second simulation via NTP 25 | ntpproxy has to run on Linux yet it can be used 26 | to test other OS-es if they utilize NTP 27 | 28 | Leap Second Test tool was tested on SLES11 however it should also 29 | run on any other Linux release. 30 | 31 | ## NTP and leap second 32 | 33 | Coordinated Universal Time (UTC) is the primary standard for civil time. 34 | UTC runs at the same frequency as International Atomic Time (TAI) however it 35 | differs from TAI by an integral number of seconds. This difference changes when 36 | leap seconds (LS) occur. 37 | Network Time Protocol (NTP) is a networking protocol for clock synchronization 38 | between computer systems. NTP provides UTC time. 39 | The International Earth Rotation and Reference System Service (IERS) watches 40 | differences in the Earth's rotation. Every six months (January or July) IERS 41 | sends a bulletin message and reports whether or not a leap second will be added 42 | in the end of the coming June or December. 43 | IERS arranges a leap second event to keep the time difference between 44 | atomic clocks and Earth’s rotation to below 0.9 seconds. Sometime prior to 45 | the day of leap second insertion the leap-indicator bits are set at 46 | the primary servers, presumably by manual means, and subsequently distributed 47 | via NTP throughout the synchronization subnet. Local NTP daemons then arm kernel 48 | via adjtimex() function and leap second is inserted or deducted by kernel 49 | at UTC midnight without any other interaction with NTP. Kernel armament can be 50 | done at any time within 24 hours preceding LS event. On the day following 51 | insertion the bits are turned off at the primary servers. 52 | 53 | LS can be also applied on the isolated computer systems with no access 54 | to the official NTP etalons. It is done via crafted file delivered by 55 | National Institutes of Standards and Technology (NIST) 56 | - see http://doc.ntp.org/4.2.6/ntpd.html#leap 57 | 58 | ## Compilation 59 | 60 | Compilation is simple like this: 61 | 62 | ``` 63 | $ make 64 | ``` 65 | 66 | OR 67 | 68 | ``` 69 | $ gcc -o ntpproxy ntpproxy.c 70 | $ gcc -o sls sls.c 71 | ``` 72 | 73 | 74 | ## Leap second test bed 75 | 76 | The leap second (LS) insertion is actually done by the kernel and NTP only 77 | plays the role of a messenger who triggers the action in advance. Therefore LS 78 | could be simulated on OS directly, by local execution of `adjtimex()` function 79 | or indirectly by setting up the leap-indicator via NTP protocol. 80 | 81 | ### Direct LS simulation 82 | 83 | LS kernel armament can be done via OS command adjtimex though it is cumbersome. 84 | A dedicated tool instead was developed: SLS (Set Leap Second): 85 | 86 | ``` 87 | # ./sls -h 88 | Usage: sls [-d seconds] [-l add|del] [-s] [-h] 89 | -d delay before leap second accomplishment. Default 600 seconds 90 | -l add: insert leap second, del: delete leap second. Default add 91 | -s leap second flag status 92 | -h help 93 | ``` 94 | 95 | SLS changes system time to be 600 seconds before midnight (see -d option 96 | for adjustment) and instructs kernel to apply the leap second at the end 97 | of the day. 98 | 99 | 100 | #### Environment setup 101 | 102 | Because system time must be modified thus SLS has to be executed by root and 103 | NTP service stopped in advance and re-started afterwards. 104 | 105 | ##### Hints 106 | 107 | ###### Checking if kernel is armed 108 | 109 | ``` 110 | # adjtimex -p | grep status | awk '{print "\nStatus:", $2; if(and($2, 16)) 111 | print "LS is INS"; else if(and($2, 32)) print "LS is DEL"; else print 112 | "LS is OFF"}' 113 | 114 | Status: 80 115 | LS is INS 116 | ``` 117 | 118 | or run 119 | 120 | ``` 121 | # ./sls -s 122 | Kernel leap second flag: add 123 | ``` 124 | or 125 | 126 | ``` 127 | # ntptime | grep status 128 | status 0x50 (INS,UNSYNC), 129 | ``` 130 | 131 | ###### Reset kernel time status 132 | 133 | useful if SLS has to be rerun without waiting for scheduled LS event 134 | 135 | ``` 136 | # adjtimex -S 0 137 | ``` 138 | or 139 | ``` 140 | # ntptime -s 0 141 | ``` 142 | 143 | When LS is applied, in `/var/log/messages` entries are logged: 144 | 145 | ``` 146 | May 2 23:59:59 tstsr604 kernel: [182259.586643] Clock: inserting leap second 147 | 23:59:60 UTC 148 | ``` 149 | 150 | or 151 | 152 | ``` 153 | May 3 00:00:00 tstsr604 kernel: [182453.585459] Clock: deleting leap second 154 | 23:59:59 UTC 155 | ``` 156 | 157 | ### Indirect LS simulation via NTP 158 | 159 | If there is a need to test many systems at the same time NTP Proxy could 160 | be used. It modifies passing NTP packets: 161 | 162 | ``` 163 | # ./ntpproxy -h 164 | Usage: ntpproxy -s server_ip [-d seconds] [-l add|del] [-v] [-h] 165 | -s IP of NTP source time server 166 | -d delay before leap second accomplishment. Default 600 seconds 167 | -l add: insert leap second, del: delete leap second. Default add 168 | -v debug information 169 | -h help 170 | ``` 171 | 172 | Located between NTP time source and NTP clients it adds a leap second 173 | indicator to the responses received by the clients. The time stamps are also 174 | adjusted so NTP clients are told that time is 600 seconds (see -d option for 175 | tuning) before midnight of the next available leap second window day. 176 | For example if current date is from the first half of year then modified NTP 177 | time shows 30th of June. If current date from the second half of the year 178 | then it shows 31st of December. 179 | 180 | NTP Proxy supports only one NTP client but other clients can be cascaded 181 | like it is shown on the figure blow. 182 | 183 | ``` 184 | ---------------- 185 | | Any real | 186 | | NTP server | 187 | ---------------- 188 | ^ 189 | | 190 | v 191 | ---------------- 192 | | NTP Proxy | <- Source of LS for the first client 193 | ---------------- 194 | ^ 195 | | 196 | v 197 | ---------------- 198 | |First NTP client| <- Source of LS for all other clients 199 | ---------------- 200 | ^ 201 | | 202 | v 203 | -------------- 204 | | All other |- 205 | | NTP clients | |- 206 | -------------- | | 207 | -------------- | 208 | -------------- 209 | ``` 210 | 211 | #### Environment setup 212 | 213 | NTP Proxy can be placed anywhere in the NTP chain, after stratum '1' server 214 | however, minding security and stability of stratum '1' servers it is reasonable 215 | setting up proxy at least after stratum '2' servers. 216 | Proxy uses NTP port 123 (UDP) therefore has to be executed by root and 217 | NTP service stopped in advance. Also NTP daemons on the servers undergoing 218 | LS verification have to be properly tuned to take the time from 219 | 'NTP Proxy' or 'First NTP client'. 220 | 221 | ###### Remark: 222 | 223 | Time on the server hosting proxy is not modified, still it is also 224 | unsynchronized (NTP has to be stopped) hence there is no sense of doing 225 | any LS OS/application tests on that node. 226 | 227 | ##### Hints 228 | 229 | ###### Kernel is armed with a leap second action only when NTP time is synchronized: 230 | 231 | ``` 232 | # ntpq -p 233 | remote refid st t when poll reach delay offset jitter 234 | ============================================================================== 235 | *tstsr604 1XX.XX.XXX.XXX 2 u 35 64 377 0.608 0.021 0.022 236 | ``` 237 | 238 | Asterisk (`*`) means that time is synchronized - it is also reflected in 239 | `/var/log/messages`: 240 | 241 | ``` 242 | Jun 30 22:25:23 tstsr001 ntpd[901102]: synchronized to 1XX.XX.XX.XX, stratum 2 243 | ``` 244 | 245 | After start of NTP client it takes a few minutes to synchronize clock. 246 | 247 | ###### Checking NTP leap second status: 248 | 249 | ``` 250 | # ntpq -c rl 251 | assID=0 status=4644 leap_add_sec, sync_ntp, 4 events, event_peer/strat_chg, 252 | version="ntpd 4.2.4p8@1.1612-o Tue Dec 20 21:31:16 UTC 2011 (1)", 253 | processor="x86_64", system="Linux/2.6.32.59-0.7-default", leap=01, 254 | stratum=3, precision=-20, rootdelay=0.898, rootdispersion=228.551, 255 | peer=29664, refid=1XX.XX.XX.XX, 256 | reftime=d57b2f51.179d8f07 Sun, Jun 30 2013 22:27:29.092, poll=6, 257 | clock=d57b3140.8864d8d8 Sun, Jun 30 2013 22:35:44.532, state=4, 258 | offset=0.021, frequency=23.985, jitter=0.024, noise=0.006, 259 | stability=0.001, tai=0 260 | ``` 261 | 262 | Meaning of `leap=` field: 263 | ``` 264 | 00 - No warning 265 | 01 - Last minute has 61 seconds 266 | 10 - Last minute has 59 seconds 267 | 11 - Clock is not synchronized 268 | ``` 269 | 270 | After midnight i.e. after applying LS, NTP Proxy stops sending leap-indicator 271 | however it takes a few minutes till NTP/kernel removes LS flags. 272 | 273 | ###### Checking if kernel is armed: 274 | 275 | ``` 276 | # adjtimex -p | grep status | awk '{print "\nStatus:", $2; if(and($2, 16)) 277 | print "LS is INS"; else if(and($2, 32)) print "LS is DEL"; else 278 | print "LS is OFF"}' 279 | 280 | Status: 80 281 | LS is INS 282 | ``` 283 | or run 284 | 285 | ``` 286 | # ./sls -s 287 | Kernel leap second flag: add 288 | ``` 289 | or 290 | 291 | ``` 292 | # ntptime | grep status 293 | status 0x50 (INS,UNSYNC), 294 | ``` 295 | 296 | 297 | ###### Reset kernel time status 298 | 299 | Uuseful if NTP PROXY has to be rerun without waiting for scheduled LS event: 300 | 301 | ``` 302 | # adjtimex -S 0 303 | ``` 304 | or 305 | ``` 306 | # ntptime -s 0 307 | ``` 308 | 309 | When LS is applied, in `/var/log/messages` entries are logged: 310 | 311 | ``` 312 | Jun 30 23:59:59 tstsr604 kernel: [182259.586643] Clock: inserting leap second 313 | 23:59:60 UTC 314 | ``` 315 | 316 | or 317 | 318 | ``` 319 | Jul 1 00:00:00 tstsr604 kernel: [182453.585459] Clock: deleting leap second 320 | 23:59:59 UTC 321 | ``` 322 | 323 | ## Useful links 324 | 325 | * [NTP Timescale and Leap Seconds](http://doc.ntp.org/4.1.0/leap.htm) 326 | * [Leap Seconds](http://maia.usno.navy.mil/leapsec.html) 327 | * [IERS Bulletin C - leap second announcement](http://hpiers.obspm.fr/iers/bul/bulc/bulletinc.dat), 328 | [alternative](http://www.iers.org/nn_10970/IERS/EN/DataProducts/EarthOrientationData/__Function/generischeTabelle__ID16.html?__nnn=true) 329 | * [IERS Bulletin C subscription](http://hpiers.obspm.fr/eop-pc/products/bulletins/bulletin_registration.html) 330 | * [RFC 1129: Internet Time Synchronization: the Network Time Protocol](http://tools.ietf.org/pdf/rfc1129) 331 | * [RFC 5905: Network Time Protocol Version 4: Protocol and Algorithms Specification](http://tools.ietf.org/html/rfc5905) 332 | -------------------------------------------------------------------------------- /ntpproxy.c: -------------------------------------------------------------------------------- 1 | //********************************************* 2 | // ntpproxy.c - NTP Proxy 3 | // 4 | // Program runs as proxy between NTP time source 5 | // and another NTP client which in turn acts as 6 | // a server for other NTP clients. 7 | // NTP Proxy modifies time stamps and 8 | // sets leap-indicator flag on the flow 9 | // from NTP time source to client. 10 | // 11 | // 03.05.2013 ver. 1.0 R. Karbowski 12 | // Initial version 13 | // 14 | // 20.01.2014 ver. 1.1 R. Karbowski 15 | // Unbuffer stdout for logging 16 | // 17 | // 24.01.2014 ver. 1.2 R. Karbowski 18 | // - print() with timestamp instead of printf() 19 | // - logging facility displays client/server IP@-es 20 | // - dump NTP packet in hex mode 21 | // - allow only mode 03 client's queries 22 | // 23 | // 10.12.2014 ver. 1.3 R. Karbowski 24 | // - hex dump implemented in internal function 25 | // - parameters parsing improvement 26 | // 27 | //********************************************* 28 | 29 | #include 30 | #include 31 | #include 32 | #include 33 | #include 34 | #include 35 | #include 36 | #include 37 | #include 38 | #include 39 | 40 | #define JAN_1970 2208988800U // 1970 - 1900 in seconds - shifts system time to NTP one 41 | #define NRLENGTH 10 // Max number of digits for delay (incl. trailing null byte) 42 | 43 | // Default values 44 | time_t bmidnight=600; // Number of seconds before midnight (leap second action) 45 | int ls=1; // 1: insert, -1: deduct leap second 46 | bool verbose=false; // Print additional information 47 | char ntpserverip[25]; // IP of NTP source time server 48 | 49 | void printNtp(); 50 | void pparam(); 51 | void usage(); 52 | void print(const char *format,...); 53 | void hexdump(char buf[], int len); 54 | 55 | // Number of days per month 56 | int dpm[]={31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; 57 | 58 | 59 | int main(argc, argv) 60 | int argc; 61 | char *argv[]; 62 | { 63 | unsigned char buf[1024], mode; 64 | 65 | int csd; // Client socket descriptor 66 | int ssd; // Server socket descriptor 67 | int i, srin_tmp_len, year, days; 68 | bool WasLsApplied=false; // Divide time befor leap second and after 69 | bool leapyear=false; 70 | time_t now, t2midnight, timeoffset, lswindow; 71 | long len, n; 72 | struct sockaddr_in srin, srin_tmp, clin; 73 | struct libnet_ntp_hdr ntp_hdr; 74 | struct tm *ts; 75 | 76 | // Unbuffer stdout 77 | setbuf(stdout, NULL); 78 | 79 | // Parse parameters 80 | pparam(argc, argv); 81 | 82 | // Check if caller is root 83 | if(getuid() != 0) 84 | { 85 | printf("Only \'root\' may launch this program\n\n"); 86 | usage(); 87 | exit(1); 88 | } 89 | 90 | // Print parameters 91 | printf("Entry parameters:\n"); 92 | printf("- source time IP: %s,\n", ntpserverip); 93 | printf("- delay: %lds,\n", bmidnight); 94 | printf("- leapsecond: %s,\n", ls==1?"add":"delete"); 95 | printf("- verbose: %s\n\n", verbose?"yes":"no"); 96 | 97 | // Calculate time offset to be added to current 98 | // time to reach end of Jun or Dec 23:50 99 | 100 | now=time(NULL); 101 | 102 | // Number of seconds to midnight 103 | t2midnight=((now/86400)*86400 + 86400) - now; 104 | 105 | ts=gmtime(&now); 106 | year=1900+ts->tm_year; 107 | 108 | // Is it leap year? 109 | if((year%4 == 0) && ((year%100 != 0) || (year%400 == 0))) 110 | leapyear=true; 111 | 112 | // Number of days to the next leap second window (end of Jun or Dec) 113 | days=0; 114 | if(ts->tm_mon < 6) 115 | { 116 | for(i=ts->tm_mon; i<6; i++) 117 | if(dpm[i] == 1 && leapyear) 118 | days+=29; 119 | else 120 | days+=dpm[i]; 121 | } 122 | else 123 | for(i=ts->tm_mon; i<12; i++) 124 | days+=dpm[i]; 125 | 126 | timeoffset=(days - ts->tm_mday)*86400 + t2midnight - bmidnight; 127 | 128 | // Time (in sec and NTP format) when leap second will be applied 129 | lswindow=now + timeoffset + bmidnight + JAN_1970; 130 | 131 | if(verbose) 132 | print("days=%d, tm_mday=%d, t2midnight=%lld, now=%d, timeoffset=%d, lswindow=%lld\n", days, ts->tm_mday, t2midnight, now, timeoffset, lswindow); 133 | 134 | now+=timeoffset; 135 | ts=gmtime(&now); 136 | 137 | if(verbose) 138 | print("now + timeoffset=%ld\n", now); 139 | 140 | if(verbose) 141 | print("%02d:%02d:%02d Day=%d, Month=%d, Year=%d\n", ts->tm_hour, ts->tm_min, ts->tm_sec, ts->tm_mday, ts->tm_mon, ts->tm_year); 142 | //exit(0); 143 | 144 | // We play as client and connect to NTP time source server 145 | print("Connecting NTP source time server: %s\n", ntpserverip); 146 | 147 | if ((csd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) 148 | { 149 | perror("csd = socket(AF_INET, SOCK_DGRAM, 0)"); 150 | exit(2); 151 | } 152 | 153 | bzero(&clin,sizeof(clin)); 154 | clin.sin_family=AF_INET; 155 | clin.sin_addr.s_addr=inet_addr(ntpserverip); 156 | clin.sin_port=htons(123); 157 | 158 | if(connect(csd, (struct sockaddr *) &clin, sizeof(clin)) == -1) 159 | { 160 | perror("connect(csd, (struct sockaddr *) &clin, sizeof(clin))"); 161 | exit(1); 162 | } 163 | 164 | 165 | // Listener part 166 | if ((ssd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) 167 | { 168 | perror("ssd = socket(AF_INET, SOCK_DGRAM, 0)"); 169 | exit(2); 170 | } 171 | 172 | bzero(&srin,sizeof(srin)); 173 | srin.sin_family=AF_INET; 174 | srin.sin_addr.s_addr=INADDR_ANY; 175 | srin.sin_port=htons(123); 176 | 177 | if(bind(ssd,(struct sockaddr *)&srin,sizeof(srin)) < 0) 178 | { 179 | perror("bind(ssd,(struct sockaddr *)&srin,sizeof(srin))"); 180 | exit(2); 181 | } 182 | 183 | print("Ready for NTP client query\n\n"); 184 | 185 | len=sizeof(ntp_hdr); 186 | 187 | while(1) 188 | { 189 | // Client's query 190 | srin_tmp_len=sizeof(srin_tmp); 191 | bzero((void *) &ntp_hdr, len); 192 | if((n=recvfrom(ssd,&ntp_hdr,len,0,(struct sockaddr *) &srin_tmp,&srin_tmp_len)) < 0) 193 | { 194 | perror("recvfrom(ssd)"); 195 | exit(2); 196 | } 197 | print("Received %i B from client %s\n", n, inet_ntoa(srin_tmp.sin_addr)); 198 | 199 | if(verbose) 200 | printNtp(&ntp_hdr); 201 | 202 | // Accept only Clinet's mode requests (3) 203 | mode=ntp_hdr.ntp_li_vn_mode & 0x7; 204 | if(mode != 3) 205 | { 206 | print("Packet's mode (%02hi) is not supported. Ignoring request\n\n", mode); 207 | continue; 208 | } 209 | 210 | // Client's query forwarded to server 211 | if((n=write(csd,&ntp_hdr,n)) < 0) 212 | { 213 | perror("write(csd)"); 214 | exit(2); 215 | } 216 | print("Client's query forwarded to server\n"); 217 | 218 | // Server's response 219 | bzero((void *) &ntp_hdr, len); 220 | if((n=read(csd,&ntp_hdr,len)) < 0) 221 | { 222 | perror("read(csd)"); 223 | exit(2); 224 | } 225 | print("Received %i B from server %s\n", n, ntpserverip); 226 | if(verbose) 227 | printNtp(&ntp_hdr); 228 | 229 | // Modification of server's response 230 | if(!WasLsApplied) 231 | { // Part before leap second window 232 | if((ntohl(ntp_hdr.ntp_xmt_ts.integer) + timeoffset) >= lswindow) 233 | { 234 | WasLsApplied=true; 235 | goto afterLS; 236 | } 237 | // Add leap second indicator 238 | if(ls == 1) 239 | ntp_hdr.ntp_li_vn_mode+=64; // Add LS 240 | else 241 | ntp_hdr.ntp_li_vn_mode+=128; // Subtract LS 242 | 243 | ntp_hdr.ntp_ref_ts.integer=htonl(ntohl(ntp_hdr.ntp_ref_ts.integer) + timeoffset); 244 | ntp_hdr.ntp_rec_ts.integer=htonl(ntohl(ntp_hdr.ntp_rec_ts.integer) + timeoffset); 245 | ntp_hdr.ntp_xmt_ts.integer=htonl(ntohl(ntp_hdr.ntp_xmt_ts.integer) + timeoffset); 246 | } 247 | else // After leap second window subtract 1 second 248 | afterLS: 249 | { 250 | ntp_hdr.ntp_ref_ts.integer=htonl(ntohl(ntp_hdr.ntp_ref_ts.integer) + timeoffset - ls); 251 | ntp_hdr.ntp_rec_ts.integer=htonl(ntohl(ntp_hdr.ntp_rec_ts.integer) + timeoffset - ls); 252 | ntp_hdr.ntp_xmt_ts.integer=htonl(ntohl(ntp_hdr.ntp_xmt_ts.integer) + timeoffset - ls); 253 | } 254 | 255 | // Modified server's response forwarded to client 256 | if((n=sendto(ssd,&ntp_hdr,n,0,(struct sockaddr *) &srin_tmp,srin_tmp_len)) < 0) 257 | { 258 | perror("sendto(ssd)"); 259 | exit(2); 260 | } 261 | 262 | print("Modified response (%i B) sent to client %s\n", n, inet_ntoa(srin_tmp.sin_addr)); 263 | if(verbose) 264 | printNtp(&ntp_hdr); 265 | 266 | printf("\n"); 267 | 268 | } 269 | 270 | close(ssd); 271 | close(csd); 272 | } 273 | 274 | 275 | //************************* 276 | // Parse parameters 277 | //************************* 278 | void pparam(argc, argv) 279 | int argc; 280 | char *argv[]; 281 | { 282 | int opt, len; 283 | char strndelay[NRLENGTH]; 284 | static struct option longopts[]= 285 | { 286 | {"source-time", required_argument, NULL, 's'}, 287 | {"delay", required_argument, NULL, 'd'}, 288 | {"leapsecond", required_argument, NULL, 'l'}, 289 | {"verbose", no_argument, NULL, 'v'}, 290 | {"help", no_argument, NULL, 'h'}, 291 | {0, 0, 0, 0} 292 | }; 293 | 294 | if(argc < 3) 295 | { 296 | usage(); 297 | exit(1); 298 | } 299 | 300 | while((opt=getopt_long(argc, argv, "s:d:l:vh", longopts, NULL)) != -1) 301 | { 302 | switch(opt) 303 | { 304 | case 's': // NTP server IP 305 | len=strlen(optarg); 306 | if(len > 15 || len < 7) // IP size -> XXX.XXX.XXX.XXX - X.X.X.X 307 | { 308 | printf("Wrong argument for option \'-s\'\n"); 309 | usage(); 310 | exit(1); 311 | } 312 | strncpy(ntpserverip,optarg,len); 313 | break; 314 | 315 | case 'd': // Set delay in seconds 316 | sscanf(optarg, "%ld", &bmidnight); 317 | snprintf(strndelay, NRLENGTH, "%ld", bmidnight); 318 | if(strcmp(optarg, strndelay) != 0) 319 | { 320 | memset(strndelay, '9', NRLENGTH-1); 321 | strndelay[NRLENGTH-1]=0; 322 | printf("Wrong argument for option \'-d\' or value out of range [-%.*s,%s]\n", (NRLENGTH-2), strndelay, strndelay); 323 | usage(); 324 | exit(1); 325 | } 326 | 327 | // bmidnight=atoi(optarg); 328 | break; 329 | 330 | case 'l': // Insert/delete leap second 331 | if(strncmp(optarg, "add", 3) == 0) 332 | { 333 | ls=1; 334 | break; 335 | } 336 | 337 | if(strncmp(optarg, "del", 3) == 0) 338 | { 339 | ls=-1; 340 | break; 341 | } 342 | 343 | printf("Wrong argument for option \'-l\'\n"); 344 | usage(); 345 | exit(1); 346 | break; 347 | 348 | case 'v': // Verbose 349 | verbose=true; 350 | break; 351 | 352 | case 'h': 353 | default: 354 | usage(); 355 | exit(1); 356 | 357 | } 358 | } 359 | 360 | } 361 | 362 | 363 | //************************* 364 | // Print usage message 365 | //************************* 366 | void usage() 367 | { 368 | printf("Usage: ntpproxy -s server_ip [-d seconds] [-l add|del] [-v] [-h]\n"); 369 | printf("-s, --source-time IP of NTP source time server\n"); 370 | printf("-d, --delay delay before leap second accomplishment. Default 600 seconds\n"); 371 | printf("-l, --leapsecond add: insert leap second, del: delete leap second. Default add\n"); 372 | printf("-v, --verbose debug information\n"); 373 | printf("-h, --help display this help\n"); 374 | } 375 | 376 | 377 | //*************************** 378 | // Parse NTP header and 379 | // print values 380 | //*************************** 381 | void printNtp(ntp_hdr) 382 | struct libnet_ntp_hdr *ntp_hdr; 383 | { 384 | unsigned char li, version, mode; 385 | register int f; 386 | register float ff; 387 | register u_int32_t luf; 388 | register u_int32_t lf; 389 | register float lff; 390 | 391 | // leap second 392 | li=ntp_hdr->ntp_li_vn_mode >> 6; 393 | 394 | // version 395 | version=(ntp_hdr->ntp_li_vn_mode >> 3) & 0x7; 396 | 397 | // mode 398 | mode=ntp_hdr->ntp_li_vn_mode & 0x7; 399 | 400 | print("Leap=%02hi, Ver=%02hi, Mode=%02hi, Stratum=%02hi, ", li, version, mode, ntp_hdr->ntp_stratum); 401 | printf("Poll=%03hi, Precision=%#02hx, ", ntp_hdr->ntp_poll, ntp_hdr->ntp_precision); 402 | f=ntohs(ntp_hdr->ntp_delay.fraction); 403 | ff=f / 65536.0; 404 | f=ff * 1000000.0; 405 | printf("Delay=%d.%06d, ", ntohs(ntp_hdr->ntp_delay.integer), f); 406 | 407 | f=ntohs(ntp_hdr->ntp_dispersion.fraction); 408 | ff=f / 65536.0; 409 | f=ff * 1000000.0; 410 | printf("Dispersion=%d.%06d, ", ntohs(ntp_hdr->ntp_dispersion.integer), f); 411 | 412 | printf("ReferenceID=%#lx, ", ntp_hdr->ntp_reference_id); 413 | 414 | luf=ntohl(ntp_hdr->ntp_ref_ts.fraction); 415 | lff=luf; 416 | lff=lff/4294967296.0; 417 | lf=lff*1000000000.0; 418 | printf("ReferenceTS=%u.%09d, ", ntohl(ntp_hdr->ntp_ref_ts.integer), lf); 419 | 420 | luf=ntohl(ntp_hdr->ntp_orig_ts.fraction); 421 | lff=luf; 422 | lff=lff/4294967296.0; 423 | lf=lff*1000000000.0; 424 | printf("OriginateTS=%u.%09d, ", ntohl(ntp_hdr->ntp_orig_ts.integer), lf); 425 | 426 | luf=ntohl(ntp_hdr->ntp_rec_ts.fraction); 427 | lff=luf; 428 | lff=lff/4294967296.0; 429 | lf=lff*1000000000.0; 430 | printf("ReceiveTS=%u.%09d, ", ntohl(ntp_hdr->ntp_rec_ts.integer), lf); 431 | 432 | luf=ntohl(ntp_hdr->ntp_xmt_ts.fraction); 433 | lff=luf; 434 | lff=lff/4294967296.0; 435 | lf=lff*1000000000.0; 436 | printf("TransmitTS=%u.%09d\n", ntohl(ntp_hdr->ntp_xmt_ts.integer), lf); 437 | 438 | // Dump hexadecimally NTP packet 439 | print("NTP header hex dump:\n"); 440 | hexdump((char *) ntp_hdr, sizeof(struct libnet_ntp_hdr)); 441 | } 442 | 443 | //*************************** 444 | // Print hexadecimally 445 | //*************************** 446 | void hexdump(char data[], int len) 447 | { 448 | int caddr=0, rcount, i; 449 | char buf[16]; 450 | 451 | while(1) 452 | { 453 | printf("%05x ", caddr); 454 | if((rcount=len-caddr) > 16) 455 | rcount=16; 456 | 457 | memcpy(buf, data+caddr, rcount); 458 | caddr+=rcount; 459 | 460 | for(i=0; i < rcount; i++) 461 | printf("%02x ", buf[i] & 0xff); 462 | 463 | for (; i < 16; i++) 464 | printf(" "); 465 | printf("|"); 466 | 467 | for(i=0; i < rcount; i++) 468 | if(isgraph(buf[i])) 469 | putchar(buf[i]); 470 | else 471 | putchar('.'); 472 | 473 | printf("|\n"); 474 | 475 | if(rcount < 16 || len <= caddr) 476 | break; 477 | } 478 | } 479 | 480 | 481 | //*************************** 482 | // Print info string with 483 | // timestamp 484 | //*************************** 485 | void print(const char *format,...) 486 | { 487 | struct timeval tv; 488 | struct tm *tm; 489 | va_list arg; 490 | 491 | if(gettimeofday(&tv, NULL) == -1) 492 | { 493 | perror("gettimeofday()"); 494 | exit(1); 495 | } 496 | 497 | if((tm=localtime(&tv.tv_sec)) == NULL) 498 | { 499 | perror("localtime()"); 500 | exit(1); 501 | } 502 | printf("%02d.%02d.%02d %02d:%02d:%02d.%06d ", tm->tm_mday, tm->tm_mon+1, tm->tm_year-100, tm->tm_hour, tm->tm_min, tm->tm_sec, tv.tv_usec); 503 | 504 | va_start(arg, format); 505 | vprintf(format, arg); 506 | va_end(arg); 507 | 508 | } 509 | 510 | -------------------------------------------------------------------------------- /sls.c: -------------------------------------------------------------------------------- 1 | //********************************************* 2 | // sls.c - Set Leap Second 3 | // 4 | // Program modifies system time and triggers 5 | // execution of 'leap second' by kernel 6 | // 7 | // 02.05.2013 ver. 1.0 R. Karbowski 8 | // Initial version 9 | // 10 | // 25.11.2014 ver. 1.1 R. Karbowski 11 | // Parameters parsing and diagnostic improvement 12 | // 13 | // 09.12.2014 ver. 1.2 R. Karbowski 14 | // Parameters parsing and diagnostic improvement- cont. 15 | // 16 | // 11.12.2014 ver. 1.2.1 R. Karbowski 17 | // Fix of bmidnight var. type issue 18 | // 19 | // 01.05.2015 ver. 1.3 R. Karbowski 20 | // Clear time state before applying LS 21 | // 22 | //********************************************* 23 | 24 | #include 25 | #include 26 | #include 27 | #include 28 | #include 29 | #include 30 | #include 31 | #include 32 | #include 33 | #include 34 | #include 35 | 36 | // Default values 37 | time_t bmidnight=600; // Number of seconds before midnight (leap second action) 38 | int ls=STA_INS; // Insert leap second 39 | bool STATUS=false; // Print LS status only 40 | 41 | #define NRLENGTH 10 // Max number of digits for delay (incl. trailing null byte) 42 | 43 | void pstatus(); 44 | void pparam(int, char **); 45 | void usage(); 46 | 47 | int main(argc, argv) 48 | int argc; 49 | char *argv[]; 50 | { 51 | struct timeval tv; 52 | struct timex tx; 53 | 54 | // Parse parameters 55 | pparam(argc, argv); 56 | 57 | // Print leap second flag status and exit 58 | if(STATUS) 59 | { 60 | pstatus(); 61 | exit(0); 62 | } 63 | 64 | // Check if caller is root 65 | if(getuid() != 0) 66 | { 67 | printf("Only \'root\' may modify OS parameters\n"); 68 | printf("Everyone can use \'-s\' option\n\n"); 69 | usage(); 70 | exit(1); 71 | } 72 | 73 | // Print parameters 74 | printf("Entry parameters: delay %lds, LS %s\n\n", bmidnight, ls==STA_INS?"add":"delete"); 75 | 76 | // Current time 77 | gettimeofday(&tv, NULL); 78 | 79 | // Next leap second 80 | tv.tv_sec +=86400 - tv.tv_sec % 86400; 81 | 82 | // Set the time to be 'bmidnight' seconds before midnight 83 | tv.tv_sec -=bmidnight; 84 | settimeofday(&tv, NULL); 85 | 86 | // Clear time state before applying LS 87 | tx.modes=ADJ_STATUS; 88 | tx.status=STA_PLL; 89 | if(adjtimex(&tx) == -1) 90 | { 91 | perror("adjtimex(1)"); 92 | exit(1); 93 | } 94 | 95 | tx.modes=ADJ_STATUS; 96 | tx.status=0x0; 97 | if(adjtimex(&tx) == -1) 98 | { 99 | perror("adjtimex(2)"); 100 | exit(1); 101 | } 102 | 103 | // Set leap second flag 104 | tx.modes=ADJ_STATUS; 105 | tx.status=ls; 106 | if(adjtimex(&tx) == -1) 107 | { 108 | perror("adjtimex(3)"); 109 | exit(1); 110 | } 111 | printf("Finished: "); 112 | pstatus(); 113 | exit(0); 114 | } 115 | 116 | //************************* 117 | // Print LS flag status 118 | //************************* 119 | void pstatus() 120 | { 121 | struct timex tx; 122 | 123 | tx.modes=0; 124 | if(adjtimex(&tx) == -1) 125 | { 126 | perror("adjtimex(4)"); 127 | exit(1); 128 | } 129 | 130 | printf("Kernel leap second flag: "); 131 | if(tx.status & STA_INS) 132 | printf("add\n"); 133 | else 134 | if(tx.status & STA_DEL) 135 | printf("delete\n"); 136 | else 137 | printf("not set\n"); 138 | } 139 | 140 | //************************* 141 | // Parse parameters 142 | //************************* 143 | void pparam(argc, argv) 144 | int argc; 145 | char *argv[]; 146 | { 147 | int opt; 148 | char strndelay[NRLENGTH]; 149 | bool RMOD=false; // Request OS modification (if option -l or -d was used) 150 | static struct option longopts[]= 151 | { 152 | {"delay", required_argument, NULL, 'd'}, 153 | {"leapsecond", required_argument, NULL, 'l'}, 154 | {"status", no_argument, NULL, 's'}, 155 | {"help", no_argument, NULL, 'h'}, 156 | {0, 0, 0, 0} 157 | }; 158 | 159 | while((opt=getopt_long(argc, argv, "d:l:sh", longopts, NULL)) != -1) 160 | { 161 | switch(opt) 162 | { 163 | case 'd': // Set delay in seconds 164 | RMOD=true; 165 | sscanf(optarg, "%ld", &bmidnight); 166 | bmidnight=abs(bmidnight); 167 | snprintf(strndelay, NRLENGTH, "%ld", bmidnight); 168 | if(strcmp(optarg, strndelay) != 0) 169 | { 170 | memset(strndelay, '9', NRLENGTH-1); 171 | strndelay[NRLENGTH-1]=0; 172 | printf("Wrong argument for option \'-d\' or value out of range [0-%s]\n", strndelay); 173 | usage(); 174 | exit(1); 175 | } 176 | break; 177 | 178 | case 'l': // Insert/delete leap second 179 | RMOD=true; 180 | if(strncmp(optarg, "add", 3) == 0) 181 | { 182 | ls=STA_INS; 183 | break; 184 | } 185 | 186 | if(strncmp(optarg, "del", 3) == 0) 187 | { 188 | ls=STA_DEL; 189 | break; 190 | } 191 | 192 | printf("Wrong argument for option \'-l\'\n"); 193 | usage(); 194 | exit(1); 195 | break; 196 | 197 | case 's': // LS flag status only 198 | STATUS=true; 199 | break; 200 | 201 | case 'h': 202 | default: 203 | usage(); 204 | exit(1); 205 | 206 | } 207 | } 208 | 209 | if(STATUS && RMOD) 210 | { 211 | printf("Options -l/-d and -s are mutually exclusive\n\n"); 212 | usage(); 213 | exit(1); 214 | } 215 | } 216 | 217 | //************************* 218 | // Print usage message 219 | //************************* 220 | void usage() 221 | { 222 | printf("Usage: sls [[[-d seconds] [-l add|del]] | [-s] | [-h]]\n"); 223 | printf("-d, --delay delay before leap second accomplishment. Default 600 seconds\n"); 224 | printf("-l, --leapsecond add: insert leap second, del: delete leap second. Default add\n"); 225 | printf("-s, --status leap second flag status\n"); 226 | printf("-h, --help display this help\n"); 227 | } 228 | 229 | 230 | --------------------------------------------------------------------------------