/***************************************************************** ** ** @(#) soaserial.c -- helper function for the dnssec zone key tools ** ** Copyright (c) Jan 2005, Holger Zuleger HZnet. All rights reserved. ** ** This software is open source. ** ** Redistribution and use in source and binary forms, with or without ** modification, are permitted provided that the following conditions ** are met: ** ** Redistributions of source code must retain the above copyright notice, ** this list of conditions and the following disclaimer. ** ** Redistributions in binary form must reproduce the above copyright notice, ** this list of conditions and the following disclaimer in the documentation ** and/or other materials provided with the distribution. ** ** Neither the name of Holger Zuleger HZnet 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 BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED ** TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR ** PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE ** LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR ** CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF ** SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS ** INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN ** CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ** ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE ** POSSIBILITY OF SUCH DAMAGE. ** *****************************************************************/ # include <stdio.h> # include <string.h> # include <stdlib.h> # include <ctype.h> # include <sys/types.h> # include <sys/stat.h> # include <time.h> # include <utime.h> # include <assert.h> #ifdef HAVE_CONFIG_H # include "config.h" #endif # include "config_zkt.h" # include "zconf.h" # include "log.h" # include "debug.h" #define extern # include "soaserial.h" #undef extern static int inc_soa_serial (FILE *fp, int use_unixtime); static int is_soa_rr (const char *line); static const char *strfindstr (const char *str, const char *search); /**************************************************************** ** ** int inc_serial (filename, use_unixtime) ** ** This function depends on a special syntax formating the ** SOA record in the zone file!! ** ** To match the SOA record, the SOA RR must be formatted ** like this: ** @ [ttl] IN SOA <master.fq.dn.> <hostmaster.fq.dn.> ( ** <SPACEes or TABs> 1234567890; serial number ** <SPACEes or TABs> 86400 ; other values ** ... ** The space from the first digit of the serial number to ** the first none white space char or to the end of the line ** must be at least 10 characters! ** So you have to left justify the serial number in a field ** of at least 10 characters like this: ** <SPACEes or TABs> 1 ; Serial ** ** Since ZKT 1.1.0 single line SOA records are also supported ** ****************************************************************/ int inc_serial (const char *fname, int use_unixtime) { FILE *fp; char buf[4095+1]; int error; int serial_pos; /** since BIND 9.4, there is a dnssec-signzone option available for serial number increment. If the user requests "unixtime"; then use this mechanism. **/ if ( use_unixtime ) return 0; if ( (fp = fopen (fname, "r+")) == NULL ) return -1; /* read until the line matches the beginning of a soa record ... */ while ( fgets (buf, sizeof buf, fp) ) { dbg_val ("inc_serial() checking line for SOA RR \"%s\"\n", buf); serial_pos = is_soa_rr (buf); if ( serial_pos ) /* SOA record found ? */ break; } if ( feof (fp) ) { fclose (fp); return -2; } dbg_val ("serial_pos = %d\n", serial_pos); if (serial_pos > 1 ) /* if we found a single line SOA RR */ fseek (fp, -(long)serial_pos, SEEK_CUR); /* go back to the beginning of the line */ error = inc_soa_serial (fp, use_unixtime); /* .. inc soa serial no ... */ dbg_val ("inc_soa_serial() returns %d\n", error); if ( fclose (fp) != 0 ) /* close the zone file in any case */ return -5; return error; } #if 0 /***************************************************************** ** check if line is the beginning of a SOA RR record, thus ** containing the string "IN .* SOA" and ends with a '(' ** returns 1 if true *****************************************************************/ static int is_soa_rr (const char *line) { const char *p; assert ( line != NULL ); /* line contains "IN" and "SOA" */ if ( (p = strfindstr (line, "IN")) && strfindstr (p+2, "SOA") ) { p = line + strlen (line) - 1; while ( p > line && isspace (*p) ) p--; if ( *p == '(' ) /* last character must be a '(' to start a multi line record */ return 1; } return 0; } #else /***************************************************************** ** ** check if line is the beginning of a SOA RR record, thus ** containing the string "IN .* SOA" and ends with a '(' ** (multiline record) or is a single line record. ** ** returns 1 if it is a multi line record (for compability to ** the old function) or the position of the serial number ** field counted from the end of the line ** *****************************************************************/ static int is_soa_rr (const char *line) { const char *p; const char *soa_p; assert ( line != NULL ); /* line contains "IN" and "SOA" ? */ if ( (p = strfindstr (line, "IN")) && (soa_p = strfindstr (p+2, "SOA")) ) { int len = strlen (line); /* check for multiline record */ p = line + len - 1; while ( p > line && isspace (*p) ) p--; if ( *p == '(' ) /* last character must be a '(' to start a multi line record */ return 1; /* line is single line record */ p = soa_p + 3; /* start just behind the SOA string */ dbg_val1 ("p = \"%s\"\n", p); p += strspn (p, " \t"); /* skip white space */ p += strcspn (p, " \t"); /* skip primary master */ p += strspn (p, " \t"); /* skip white space */ p += strcspn (p, " \t"); /* skip mail address */ dbg_val1 ("p = \"%s\"\n", p); dbg_val1 ("is_soa_rr returns = %d\n", (line+len) - p); return (line+len) - p; /* position of serial nr from the end of the line */ } return 0; } #endif /***************************************************************** ** Find string 'search' in 'str' and ignore case in comparison. ** returns the position of 'search' in 'str' or NULL if not found. *****************************************************************/ static const char *strfindstr (const char *str, const char *search) { const char *p; int c; assert ( str != NULL ); assert ( search != NULL ); c = tolower (*search); p = str; do { while ( *p && tolower (*p) != c ) p++; if ( strncasecmp (p, search, strlen (search)) == 0 ) return p; p++; } while ( *p ); return NULL; } /***************************************************************** ** return the serial number of the given time in the form ** of YYYYmmdd00 as ulong value *****************************************************************/ static ulong serialtime (time_t sec) { struct tm *t; ulong serialtime; t = gmtime (&sec); serialtime = (t->tm_year + 1900) * 10000; serialtime += (t->tm_mon+1) * 100; serialtime += t->tm_mday; serialtime *= 100; return serialtime; } /***************************************************************** ** inc_soa_serial (fp, use_unixtime) ** increment the soa serial number of the file 'fp' ** 'fp' must be opened "r+" ** returns 0 on success or a negative value in case of an error *****************************************************************/ static int inc_soa_serial (FILE *fp, int use_unixtime) { int c; long pos, eos; ulong serial; int digits; ulong today; /* move forward until any non ws is reached */ while ( (c = getc (fp)) != EOF && isspace (c) ) ; ungetc (c, fp); /* push back the last char */ pos = ftell (fp); /* mark position */ serial = 0L; /* read in the current serial number */ /* be aware of the trailing space in the format string !! */ if ( fscanf (fp, "%lu ", &serial) != 1 ) /* try to get serial no */ return -3; eos = ftell (fp); /* mark first non digit/ws character pos */ digits = eos - pos; if ( digits < 10 ) /* not enough space for serial no ? */ return -4; today = time (NULL); if ( !use_unixtime ) { today = serialtime (today); /* YYYYmmdd00 */ if ( serial > 1970010100L && serial < today ) serial = today; /* set to current time */ serial++; /* increment anyway */ } fseek (fp, pos, SEEK_SET); /* go back to the beginning */ fprintf (fp, "%-*lu", digits, serial); /* write as many chars as before */ return 0; /* yep! */ } /***************************************************************** ** return the error text of the inc_serial return coode *****************************************************************/ const char *inc_errstr (int err) { switch ( err ) { case -1: return "couldn't open zone file for modifying"; case -2: return "unexpected end of file"; case -3: return "no serial number found in zone file"; case -4: return "not enough space left for serialno"; case -5: return "error on closing zone file"; } return ""; } #ifdef SOA_TEST const char *progname; main (int argc, char *argv[]) { ulong now; int err; char cmd[255]; progname = *argv; now = time (NULL); now = serialtime (now); printf ("now = %lu\n", now); if ( (err = inc_serial (argv[1], 0)) < 0 ) { fprintf (stderr, "can't change serial no: errno=%d %s\n", err, inc_errstr (err)); exit (1); } snprintf (cmd, sizeof(cmd), "head -15 %s", argv[1]); system (cmd); } #endif