mdw@git.distorted.org.uk Git - secnet/blob - util.c

   1 /* $Log: util.c,v $
   2  * Revision 1.2  1996/04/14 16:34:36  sde1000
   3  * Added syslog support
   4  * mpbin/mpstring functions moved from dh.c
   5  *
   6  * Revision 1.1  1996/03/14 17:05:03  sde1000
   7  * Initial revision
   8  *
   9  */
  10
  11 #include "secnet.h"
  12 #include <stdio.h>
  13 #include <string.h>
  14 #include <errno.h>
  15 #include <unistd.h>
  16 #include <limits.h>
  17 #include <assert.h>
  18 #include <sys/wait.h>
  19 #include "util.h"
  20 #include "unaligned.h"
  21
  22 #define MIN_BUFFER_SIZE 64
  23 #define DEFAULT_BUFFER_SIZE 4096
  24 #define MAX_BUFFER_SIZE 131072
  25
  26 static char *hexdigits="0123456789abcdef";
  27
  28 uint32_t message_level=M_WARNING|M_ERROR|M_FATAL;
  29 uint32_t syslog_level=M_WARNING|M_ERROR|M_FATAL;
  30 static uint32_t current_phase=0;
  31
  32 struct phase_hook {
  33     hook_fn *fn;
  34     void *state;
  35     struct phase_hook *next;
  36 };
  37
  38 static struct phase_hook *hooks[NR_PHASES]={NULL,};
  39
  40 static void vMessage(uint32_t class, char *message, va_list args)
  41 {
  42     FILE *dest=stdout;
  43     if (class & message_level) {
  44         if (class&M_FATAL || class&M_ERROR || class&M_WARNING) {
  45             dest=stderr;
  46         }
  47         vfprintf(dest,message,args);
  48     }
  49 /* XXX do something about syslog output here */
  50 #if 0
  51     /* Maybe send message to syslog */
  52     vsprintf(buff, message, args);
  53     /* XXX Send each line as a separate log entry */
  54     log(syslog_prio[level], buff);
  55 #endif /* 0 */
  56 }
  57
  58 void Message(uint32_t class, char *message, ...)
  59 {
  60     va_list ap;
  61
  62     va_start(ap,message);
  63
  64     vMessage(class,message,ap);
  65
  66     va_end(ap);
  67 }
  68
  69 static void vfatal(int status, bool_t perror, char *message, va_list args)
  70 {
  71     int err;
  72
  73     err=errno;
  74
  75     enter_phase(PHASE_SHUTDOWN);
  76     if (perror) {
  77         Message(M_FATAL, "secnet fatal error: ");
  78         vMessage(M_FATAL, message, args);
  79         Message(M_FATAL, ": %s\n",strerror(err));
  80     }
  81     else {
  82         Message(M_FATAL, "secnet fatal error: ");
  83         vMessage(M_FATAL,message,args);
  84     }
  85     exit(status);
  86 }
  87
  88 void fatal(char *message, ...)
  89 {
  90     va_list args;
  91     va_start(args,message);
  92     vfatal(current_phase,False,message,args);
  93     va_end(args);
  94 }
  95
  96 void fatal_status(int status, char *message, ...)
  97 {
  98     va_list args;
  99     va_start(args,message);
 100     vfatal(status,False,message,args);
 101     va_end(args);
 102 }
 103
 104 void fatal_perror(char *message, ...)
 105 {
 106     va_list args;
 107     va_start(args,message);
 108     vfatal(current_phase,True,message,args);
 109     va_end(args);
 110 }
 111
 112 void fatal_perror_status(int status, char *message, ...)
 113 {
 114     va_list args;
 115     va_start(args,message);
 116     vfatal(status,True,message,args);
 117     va_end(args);
 118 }
 119
 120 void cfgfatal(struct cloc loc, string_t facility, char *message, ...)
 121 {
 122     va_list args;
 123
 124     va_start(args,message);
 125
 126     enter_phase(PHASE_SHUTDOWN);
 127
 128     if (loc.file && loc.line) {
 129         Message(M_FATAL, "config error (%s, %s:%d): ",facility,loc.file,
 130                 loc.line);
 131     } else if (!loc.file && loc.line) {
 132         Message(M_FATAL, "config error (%s, line %d): ",facility,loc.line);
 133     } else {
 134         Message(M_FATAL, "config error (%s): ",facility);
 135     }
 136
 137     vMessage(M_FATAL,message,args);
 138     va_end(args);
 139     exit(current_phase);
 140 }
 141
 142 char *safe_strdup(char *s, char *message)
 143 {
 144     char *d;
 145     d=strdup(s);
 146     if (!d) {
 147         fatal_perror(message);
 148     }
 149     return d;
 150 }
 151
 152 void *safe_malloc(size_t size, char *message)
 153 {
 154     void *r;
 155     r=malloc(size);
 156     if (!r) {
 157         fatal_perror(message);
 158     }
 159     return r;
 160 }
 161
 162 /* Convert a buffer into its MP_INT representation */
 163 void read_mpbin(MP_INT *a, uint8_t *bin, int binsize)
 164 {
 165     char *buff;
 166     int i;
 167
 168     buff=safe_malloc(binsize*2 + 1,"read_mpbin");
 169
 170     for (i=0; i<binsize; i++) {
 171         buff[i*2]=hexdigits[(bin[i] & 0xf0) >> 4];
 172         buff[i*2+1]=hexdigits[(bin[i] & 0xf)];
 173     }
 174     buff[binsize*2]=0;
 175
 176     mpz_set_str(a, buff, 16);
 177     free(buff);
 178 }
 179
 180 /* Convert a MP_INT into a hex string */
 181 char *write_mpstring(MP_INT *a)
 182 {
 183     char *buff;
 184
 185     buff=safe_malloc(mpz_sizeinbase(a,16)+2,"write_mpstring");
 186     mpz_get_str(buff, 16, a);
 187     return buff;
 188 }
 189
 190 static uint8_t hexval(uint8_t c)
 191 {
 192     switch (c) {
 193     case '0': return 0;
 194     case '1': return 1;
 195     case '2': return 2;
 196     case '3': return 3;
 197     case '4': return 4;
 198     case '5': return 5;
 199     case '6': return 6;
 200     case '7': return 7;
 201     case '8': return 8;
 202     case '9': return 9;
 203     case 'a': return 10;
 204     case 'A': return 10;
 205     case 'b': return 11;
 206     case 'B': return 11;
 207     case 'c': return 12;
 208     case 'C': return 12;
 209     case 'd': return 13;
 210     case 'D': return 13;
 211     case 'e': return 14;
 212     case 'E': return 14;
 213     case 'f': return 15;
 214     case 'F': return 15;
 215     }
 216     return -1;
 217 }
 218
 219 /* Convert a MP_INT into a buffer; return length; truncate if necessary */
 220 uint32_t write_mpbin(MP_INT *a, uint8_t *buffer, uint32_t buflen)
 221 {
 222     char *hb;
 223     int i,j,l;
 224
 225     if (buflen==0) return 0;
 226     hb=write_mpstring(a);
 227
 228     l=strlen(hb);
 229     i=0; j=0;
 230     if (l&1) {
 231         /* The number starts with a half-byte */
 232         buffer[i++]=hexval(hb[j++]);
 233     }
 234     for (; hb[j] && i<buflen; i++) {
 235         buffer[i]=(hexval(hb[j])<<4)|hexval(hb[j+1]);
 236         j+=2;
 237     }
 238     free(hb);
 239     return i;
 240 }
 241
 242 bool_t subnet_match(struct subnet *s, uint32_t address)
 243 {
 244     return (s->prefix==(address&s->mask));
 245 }
 246
 247 bool_t subnet_matches_list(struct subnet_list *list, uint32_t address)
 248 {
 249     uint32_t i;
 250     for (i=0; i<list->entries; i++) {
 251         if (list->list[i].prefix == (address&list->list[i].mask)) return True;
 252     }
 253     return False;
 254 }
 255
 256 bool_t subnets_intersect(struct subnet a, struct subnet b)
 257 {
 258     uint32_t mask=a.mask&b.mask;
 259     return ((a.prefix&mask)==(b.prefix&mask));
 260 }
 261
 262 bool_t subnet_intersects_with_list(struct subnet a, struct subnet_list *b)
 263 {
 264     uint32_t i;
 265
 266     for (i=0; i<b->entries; i++) {
 267         if (subnets_intersect(a,b->list[i])) return True;
 268     }
 269     return False;
 270 }
 271
 272 bool_t subnet_lists_intersect(struct subnet_list *a, struct subnet_list *b)
 273 {
 274     uint32_t i;
 275     for (i=0; i<a->entries; i++) {
 276         if (subnet_intersects_with_list(a->list[i],b)) return True;
 277     }
 278     return False;
 279 }
 280
 281 /* The string buffer must be at least 16 bytes long */
 282 string_t ipaddr_to_string(uint32_t addr)
 283 {
 284     uint8_t a,b,c,d;
 285     string_t s;
 286
 287     s=safe_malloc(16,"ipaddr_to_string");
 288     a=addr>>24;
 289     b=addr>>16;
 290     c=addr>>8;
 291     d=addr;
 292     snprintf(s, 16, "%d.%d.%d.%d", a, b, c, d);
 293     return s;
 294 }
 295
 296 string_t subnet_to_string(struct subnet *sn)
 297 {
 298     uint32_t mask=sn->mask, addr=sn->prefix;
 299     uint8_t a,b,c,d;
 300     string_t s;
 301     int i;
 302
 303     s=safe_malloc(19,"subnet_to_string");
 304     a=addr>>24;
 305     b=addr>>16;
 306     c=addr>>8;
 307     d=addr;
 308     for (i=0; mask; i++) {
 309         mask=(mask<<1);
 310     }
 311     if (i!=sn->len) {
 312         fatal("subnet_to_string: invalid subnet structure!\n");
 313     }
 314     snprintf(s, 19, "%d.%d.%d.%d/%d", a, b, c, d, sn->len);
 315     return s;
 316 }
 317
 318 int sys_cmd(const char *path, char *arg, ...)
 319 {
 320     va_list ap;
 321     int rv;
 322     pid_t c;
 323
 324     va_start(ap,arg);
 325     c=fork();
 326     if (c) {
 327         /* Parent -> wait for child */
 328         waitpid(c,&rv,0);
 329     } else if (c==0) {
 330         char *args[100];
 331         int i;
 332         /* Child -> exec command */
 333         args[0]=arg;
 334         i=1;
 335         while ((args[i++]=va_arg(ap,char *)));
 336         execvp(path,args);
 337         exit(1);
 338     } else {
 339         /* Error */
 340         fatal_perror("sys_cmd(%s,%s,...)");
 341     }
 342
 343     va_end(ap);
 344     return rv;
 345 }
 346
 347 /* Take a list of log closures and merge them */
 348 struct loglist {
 349     struct log_if *l;
 350     struct loglist *next;
 351 };
 352
 353 static void log_vmulti(void *state, int priority, char *message, va_list args)
 354 {
 355     struct loglist *st=state, *i;
 356
 357     for (i=st; i; i=i->next) {
 358         i->l->vlog(i->l->st,priority,message,args);
 359     }
 360 }
 361
 362 static void log_multi(void *st, int priority, char *message, ...)
 363 {
 364     va_list ap;
 365
 366     va_start(ap,message);
 367
 368     log_vmulti(st,priority,message,ap);
 369
 370     va_end(ap);
 371 }
 372
 373 struct log_if *init_log(list_t *ll)
 374 {
 375     int i=0;
 376     item_t *item;
 377     closure_t *cl;
 378     struct loglist *l=NULL, *n;
 379     struct log_if *r;
 380
 381     while ((item=list_elem(ll,i++))) {
 382         if (item->type!=t_closure) {
 383             cfgfatal(item->loc,"init_log","item is not a closure");
 384         }
 385         cl=item->data.closure;
 386         if (cl->type!=CL_LOG) {
 387             cfgfatal(item->loc,"init_log","closure is not a logger");
 388         }
 389         n=safe_malloc(sizeof(*n),"init_log");
 390         n->l=cl->interface;
 391         n->next=l;
 392         l=n;
 393     }
 394     if (!l) {
 395         fatal("init_log: none of the items in the list are loggers");
 396     }
 397     r=safe_malloc(sizeof(*r), "init_log");
 398     r->st=l;
 399     r->log=log_multi;
 400     r->vlog=log_vmulti;
 401     return r;
 402 }
 403
 404 struct logfile {
 405     closure_t cl;
 406     struct log_if ops;
 407     FILE *f;
 408 };
 409
 410 static void logfile_vlog(void *state, int priority, char *message,
 411                          va_list args)
 412 {
 413     struct logfile *st=state;
 414
 415     vfprintf(st->f,message,args);
 416     fprintf(st->f,"\n");
 417 }
 418
 419 static void logfile_log(void *state, int priority, char *message, ...)
 420 {
 421     va_list ap;
 422
 423     va_start(ap,message);
 424     logfile_vlog(state,priority,message,ap);
 425     va_end(ap);
 426 }
 427
 428 static list_t *logfile_apply(closure_t *self, struct cloc loc, dict_t *context,
 429                              list_t *data)
 430 {
 431     struct logfile *st;
 432
 433     st=safe_malloc(sizeof(*st),"logfile_apply");
 434     st->cl.description="logfile";
 435     st->cl.type=CL_LOG;
 436     st->cl.apply=NULL;
 437     st->cl.interface=&st->ops;
 438     st->ops.st=st;
 439     st->ops.log=logfile_log;
 440     st->ops.vlog=logfile_vlog;
 441     st->f=stderr; /* XXX ignore args */
 442
 443     return new_closure(&st->cl);
 444 }
 445
 446 static char *phases[NR_PHASES]={
 447     "PHASE_INIT",
 448     "PHASE_GETOPTS",
 449     "PHASE_READCONFIG",
 450     "PHASE_SETUP",
 451     "PHASE_GETRESOURCES",
 452     "PHASE_DROPPRIV",
 453     "PHASE_RUN",
 454     "PHASE_SHUTDOWN"
 455 };
 456
 457 void enter_phase(uint32_t new_phase)
 458 {
 459     struct phase_hook *i;
 460
 461     if (hooks[new_phase])
 462         Message(M_DEBUG_PHASE,"Running hooks for %s...\n", phases[new_phase]);
 463     current_phase=new_phase;
 464
 465     for (i=hooks[new_phase]; i; i=i->next)
 466         i->fn(i->state, new_phase);
 467     Message(M_DEBUG_PHASE,"Now in %s\n",phases[new_phase]);
 468 }
 469
 470 bool_t add_hook(uint32_t phase, hook_fn *fn, void *state)
 471 {
 472     struct phase_hook *h;
 473
 474     h=safe_malloc(sizeof(*h),"add_hook");
 475     h->fn=fn;
 476     h->state=state;
 477     h->next=hooks[phase];
 478     hooks[phase]=h;
 479     return True;
 480 }
 481
 482 bool_t remove_hook(uint32_t phase, hook_fn *fn, void *state)
 483 {
 484     fatal("remove_hook: not implemented\n");
 485
 486     return False;
 487 }
 488
 489 void log(struct log_if *lf, int priority, char *message, ...)
 490 {
 491     va_list ap;
 492
 493     va_start(ap,message);
 494     lf->vlog(lf->st,priority,message,ap);
 495     va_end(ap);
 496 }
 497
 498 struct buffer {
 499     closure_t cl;
 500     struct buffer_if ops;
 501 };
 502
 503 void buffer_assert_free(struct buffer_if *buffer, string_t file, uint32_t line)
 504 {
 505     if (!buffer->free) {
 506         fatal("BUF_ASSERT_FREE, %s line %d, owned by %s\n",
 507               file,line,buffer->owner);
 508     }
 509 }
 510
 511 void buffer_assert_used(struct buffer_if *buffer, string_t file, uint32_t line)
 512 {
 513     if (buffer->free) {
 514         fatal("BUF_ASSERT_USED, %s line %d, last owned by %s\n",
 515               file,line,buffer->owner);
 516     }
 517 }
 518
 519 void buffer_init(struct buffer_if *buffer, uint32_t max_start_pad)
 520 {
 521     buffer->start=buffer->base+max_start_pad;
 522     buffer->size=0;
 523 }
 524
 525 void *buf_append(struct buffer_if *buf, uint32_t amount) {
 526     void *p;
 527     p=buf->start + buf->size;
 528     buf->size+=amount;
 529     return p;
 530 }
 531
 532 void *buf_prepend(struct buffer_if *buf, uint32_t amount) {
 533     buf->size+=amount;
 534     return buf->start-=amount;
 535 }
 536
 537 void *buf_unappend(struct buffer_if *buf, uint32_t amount) {
 538     if (buf->size < amount) return 0;
 539     return buf->start+(buf->size-=amount);
 540 }
 541
 542 void *buf_unprepend(struct buffer_if *buf, uint32_t amount) {
 543     void *p;
 544     p=buf->start;
 545     buf->start+=amount;
 546     buf->size-=amount;
 547     return p;
 548 }
 549
 550 /* Append a two-byte length and the string to the buffer. Length is in
 551    network byte order. */
 552 void buf_append_string(struct buffer_if *buf, string_t s)
 553 {
 554     uint16_t len;
 555
 556     len=strlen(s);
 557     buf_append_uint16(buf,len);
 558     memcpy(buf_append(buf,len),s,len);
 559 }
 560
 561 void buffer_new(struct buffer_if *buf, uint32_t len)
 562 {
 563     buf->free=True;
 564     buf->owner=NULL;
 565     buf->flags=0;
 566     buf->loc.file=NULL;
 567     buf->loc.line=0;
 568     buf->size=0;
 569     buf->len=len;
 570     buf->start=NULL;
 571     buf->base=safe_malloc(len,"buffer_new");
 572 }
 573
 574 static list_t *buffer_apply(closure_t *self, struct cloc loc, dict_t *context,
 575                             list_t *args)
 576 {
 577     struct buffer *st;
 578     item_t *item;
 579     dict_t *dict;
 580     bool_t lockdown=False;
 581     uint32_t len=DEFAULT_BUFFER_SIZE;
 582
 583     st=safe_malloc(sizeof(*st),"buffer_apply");
 584     st->cl.description="buffer";
 585     st->cl.type=CL_BUFFER;
 586     st->cl.apply=NULL;
 587     st->cl.interface=&st->ops;
 588
 589     /* First argument, if present, is buffer length */
 590     item=list_elem(args,0);
 591     if (item) {
 592         if (item->type!=t_number) {
 593             cfgfatal(st->ops.loc,"buffer","first parameter must be a "
 594                      "number (buffer size)\n");
 595         }
 596         len=item->data.number;
 597         if (len<MIN_BUFFER_SIZE) {
 598             cfgfatal(st->ops.loc,"buffer","ludicrously small buffer size\n");
 599         }
 600         if (len>MAX_BUFFER_SIZE) {
 601             cfgfatal(st->ops.loc,"buffer","ludicrously large buffer size\n");
 602         }
 603     }
 604     /* Second argument, if present, is a dictionary */
 605     item=list_elem(args,1);
 606     if (item) {
 607         if (item->type!=t_dict) {
 608             cfgfatal(st->ops.loc,"buffer","second parameter must be a "
 609                      "dictionary\n");
 610         }
 611         dict=item->data.dict;
 612         lockdown=dict_read_bool(dict,"lockdown",False,"buffer",st->ops.loc,
 613                                 False);
 614     }
 615
 616     buffer_new(&st->ops,len);
 617     if (lockdown) {
 618         /* XXX mlock the buffer if possible */
 619     }
 620
 621     return new_closure(&st->cl);
 622 }
 623
 624 init_module util_module;
 625 void util_module(dict_t *dict)
 626 {
 627     add_closure(dict,"logfile",logfile_apply);
 628     add_closure(dict,"sysbuffer",buffer_apply);
 629 }