src/pluto/defs.c

   1 /* misc. universal things
   2  * Copyright (C) 1998-2001  D. Hugh Redelmeier.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU General Public License as published by the
   6  * Free Software Foundation; either version 2 of the License, or (at your
   7  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  11  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * for more details.
  13  *
  14  * RCSID $Id$
  15  */
  16
  17 #include <stdlib.h>
  18 #include <string.h>
  19 #include <stdio.h>
  20 #include <dirent.h>
  21 #include <time.h>
  22 #include <sys/types.h>
  23 #include <sys/stat.h>
  24
  25 #include <freeswan.h>
  26
  27 #include "constants.h"
  28 #include "defs.h"
  29 #include "log.h"
  30 #include "whack.h"      /* for RC_LOG_SERIOUS */
  31
  32 const chunk_t empty_chunk = { NULL, 0 };
  33
  34 bool
  35 all_zero(const unsigned char *m, size_t len)
  36 {
  37     size_t i;
  38
  39     for (i = 0; i != len; i++)
  40         if (m[i] != '\0')
  41             return FALSE;
  42     return TRUE;
  43 }
  44
  45 /* memory allocation
  46  *
  47  * LEAK_DETECTIVE puts a wrapper around each allocation and maintains
  48  * a list of live ones.  If a dead one is freed, an assertion MIGHT fail.
  49  * If the live list is currupted, that will often be detected.
  50  * In the end, report_leaks() is called, and the names of remaining
  51  * live allocations are printed.  At the moment, it is hoped, not that
  52  * the list is empty, but that there will be no surprises.
  53  *
  54  * Accepted Leaks:
  55  * - "struct iface" and "device name" (for "discovered" net interfaces)
  56  * - "struct event in event_schedule()" (events not associated with states)
  57  * - "Pluto lock name" (one only, needed until end -- why bother?)
  58  */
  59
  60 #ifdef LEAK_DETECTIVE
  61
  62 /* this magic number is 3671129837 decimal (623837458 complemented) */
  63 #define LEAK_MAGIC 0xDAD0FEEDul
  64
  65 union mhdr {
  66     struct {
  67         const char *name;
  68         union mhdr *older, *newer;
  69         unsigned long magic;
  70     } i;    /* info */
  71     unsigned long junk; /* force maximal alignment */
  72 };
  73
  74 static union mhdr *allocs = NULL;
  75
  76 void *alloc_bytes(size_t size, const char *name)
  77 {
  78     union mhdr *p = malloc(sizeof(union mhdr) + size);
  79
  80     if (p == NULL)
  81         exit_log("unable to malloc %lu bytes for %s"
  82             , (unsigned long) size, name);
  83     p->i.name = name;
  84     p->i.older = allocs;
  85     if (allocs != NULL)
  86         allocs->i.newer = p;
  87     allocs = p;
  88     p->i.newer = NULL;
  89     p->i.magic = LEAK_MAGIC;
  90
  91     memset(p+1, '\0', size);
  92     return p+1;
  93 }
  94
  95 void *
  96 clone_bytes(const void *orig, size_t size, const char *name)
  97 {
  98     void *p = alloc_bytes(size, name);
  99
 100     memcpy(p, orig, size);
 101     return p;
 102 }
 103
 104 void
 105 pfree(void *ptr)
 106 {
 107     union mhdr *p;
 108
 109     passert(ptr != NULL);
 110     p = ((union mhdr *)ptr) - 1;
 111     passert(p->i.magic == LEAK_MAGIC);
 112     if (p->i.older != NULL)
 113     {
 114         passert(p->i.older->i.newer == p);
 115         p->i.older->i.newer = p->i.newer;
 116     }
 117     if (p->i.newer == NULL)
 118     {
 119         passert(p == allocs);
 120         allocs = p->i.older;
 121     }
 122     else
 123     {
 124         passert(p->i.newer->i.older == p);
 125         p->i.newer->i.older = p->i.older;
 126     }
 127     p->i.magic = ~LEAK_MAGIC;
 128     free(p);
 129 }
 130
 131 void
 132 report_leaks(void)
 133 {
 134     union mhdr
 135         *p = allocs,
 136         *pprev = NULL;
 137     unsigned long n = 0;
 138
 139     while (p != NULL)
 140     {
 141         passert(p->i.magic == LEAK_MAGIC);
 142         passert(pprev == p->i.newer);
 143         pprev = p;
 144         p = p->i.older;
 145         n++;
 146         if (p == NULL || pprev->i.name != p->i.name)
 147         {
 148             if (n != 1)
 149                 plog("leak: %lu * %s", n, pprev->i.name);
 150             else
 151                 plog("leak: %s", pprev->i.name);
 152             n = 0;
 153         }
 154     }
 155 }
 156
 157 #else /* !LEAK_DETECTIVE */
 158
 159 void *alloc_bytes(size_t size, const char *name)
 160 {
 161     void *p = malloc(size);
 162
 163     if (p == NULL)
 164         exit_log("unable to malloc %lu bytes for %s"
 165             , (unsigned long) size, name);
 166     memset(p, '\0', size);
 167     return p;
 168 }
 169
 170 void *clone_bytes(const void *orig, size_t size, const char *name)
 171 {
 172     void *p = malloc(size);
 173
 174     if (p == NULL)
 175         exit_log("unable to malloc %lu bytes for %s"
 176             , (unsigned long) size, name);
 177     memcpy(p, orig, size);
 178     return p;
 179 }
 180 #endif /* !LEAK_DETECTIVE */
 181
 182 /*  Note that there may be as many as six IDs that are temporary at
 183  *  one time before unsharing the two ends of a connection. So we need
 184  *  at least six temporary buffers for DER_ASN1_DN IDs.
 185  *  We rotate them. Be careful!
 186  */
 187 #define MAX_BUF         10
 188
 189 char*
 190 temporary_cyclic_buffer(void)
 191 {
 192     static char buf[MAX_BUF][BUF_LEN];  /* MAX_BUF internal buffers */
 193     static int counter = 0;                     /* cyclic counter */
 194
 195     if (++counter == MAX_BUF) counter = 0;      /* next internal buffer */
 196     return buf[counter];                        /* assign temporary buffer */
 197 }
 198
 199 /* concatenates two sub paths into a string with a maximum size of BUF_LEN
 200  * use for temporary storage only
 201  */
 202 const char*
 203 concatenate_paths(const char *a, const char *b)
 204 {
 205     char *c;
 206
 207     if (*b == '/' || *b == '.')
 208         return b;
 209
 210     c = temporary_cyclic_buffer();
 211     snprintf(c, BUF_LEN, "%s/%s", a, b);
 212     return c;
 213 }
 214
 215 /*  compare two chunks, returns zero if a equals b
 216  *  negative/positive if a is earlier/later in the alphabet than b
 217  */
 218 int
 219 cmp_chunk(chunk_t a, chunk_t b)
 220 {
 221     int cmp_len, len, cmp_value;
 222
 223     cmp_len = a.len - b.len;
 224     len = (cmp_len < 0)? a.len : b.len;
 225     cmp_value = memcmp(a.ptr, b.ptr, len);
 226
 227     return (cmp_value == 0)? cmp_len : cmp_value;
 228 };
 229
 230 /* moves a chunk to a memory position, chunk is freed afterwards
 231  * position pointer is advanced after the insertion point
 232  */
 233 void
 234 mv_chunk(u_char **pos, chunk_t content)
 235 {
 236     if (content.len > 0)
 237     {
 238         chunkcpy(*pos, content);
 239         freeanychunk(content);
 240     }
 241 }
 242
 243 /*
 244  * write the binary contents of a chunk_t to a file
 245  */
 246 bool
 247 write_chunk(const char *filename, const char *label, chunk_t ch
 248 , mode_t mask, bool force)
 249 {
 250     mode_t oldmask;
 251     FILE *fd;
 252
 253     if (!force)
 254     {
 255         fd = fopen(filename, "r");
 256         if (fd)
 257         {
 258             fclose(fd);
 259             plog("  %s file '%s' already exists", label, filename);
 260             return FALSE;
 261         }
 262     }
 263
 264     /* set umask */
 265     oldmask = umask(mask);
 266
 267     fd = fopen(filename, "w");
 268
 269     if (fd)
 270     {
 271         fwrite(ch.ptr, sizeof(u_char), ch.len, fd);
 272         fclose(fd);
 273         plog("  written %s file '%s' (%d bytes)", label, filename, (int)ch.len);
 274         umask(oldmask);
 275         return TRUE;
 276     }
 277     else
 278     {
 279         plog("  could not open %s file '%s' for writing", label, filename);
 280         umask(oldmask);
 281         return FALSE;
 282     }
 283 }
 284
 285 /* Names of the months */
 286
 287 static const char* months[] = {
 288     "Jan", "Feb", "Mar", "Apr", "May", "Jun",
 289     "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
 290 };
 291
 292
 293 /*
 294  *  Display a date either in local or UTC time
 295  */
 296 char*
 297 timetoa(const time_t *time, bool utc)
 298 {
 299     static char buf[TIMETOA_BUF];
 300
 301     if (*time == UNDEFINED_TIME)
 302         sprintf(buf, "--- -- --:--:--%s----", (utc)?" UTC ":" ");
 303     else
 304     {
 305         struct tm *t = (utc)? gmtime(time) : localtime(time);
 306
 307         sprintf(buf, "%s %02d %02d:%02d:%02d%s%04d",
 308             months[t->tm_mon], t->tm_mday, t->tm_hour, t->tm_min, t->tm_sec,
 309             (utc)?" UTC ":" ", t->tm_year + 1900
 310         );
 311     }
 312     return buf;
 313 }
 314
 315 /*  checks if the expiration date has been reached and
 316  *  warns during the warning_interval of the imminent
 317  *  expiry. strict=TRUE declares a fatal error,
 318  *  strict=FALSE issues a warning upon expiry.
 319  */
 320 const char*
 321 check_expiry(time_t expiration_date, int warning_interval, bool strict)
 322 {
 323     time_t now;
 324     int time_left;
 325
 326     if (expiration_date == UNDEFINED_TIME)
 327       return "ok (expires never)";
 328
 329     /* determine the current time */
 330     time(&now);
 331
 332     time_left = (expiration_date - now);
 333     if (time_left < 0)
 334         return strict? "fatal (expired)" : "warning (expired)";
 335
 336     if (time_left > 86400*warning_interval)
 337         return "ok";
 338     {
 339         static char buf[35]; /* temporary storage */
 340         const char* unit = "second";
 341
 342         if (time_left > 172800)
 343         {
 344             time_left /= 86400;
 345             unit = "day";
 346         }
 347         else if (time_left > 7200)
 348         {
 349             time_left /= 3600;
 350             unit = "hour";
 351         }
 352         else if (time_left > 120)
 353         {
 354             time_left /= 60;
 355             unit = "minute";
 356         }
 357         snprintf(buf, 35, "warning (expires in %d %s%s)", time_left,
 358                  unit, (time_left == 1)?"":"s");
 359         return buf;
 360     }
 361 }
 362
 363
 364 /*
 365  *  Filter eliminating the directory entries '.' and '..'
 366  */
 367 int
 368 file_select(const struct dirent *entry)
 369 {
 370     return strcmp(entry->d_name, "." ) &&
 371            strcmp(entry->d_name, "..");
 372 }
 373
 374