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_list *list, uint32_t address)
 243 {
 244     uint32_t i;
 245     for (i=0; i<list->entries; i++) {
 246         if (list->list[i].prefix == (address&list->list[i].mask)) return True;
 247     }
 248     return False;
 249 }
 250
 251 /* The string buffer must be at least 16 bytes long */
 252 string_t ipaddr_to_string(uint32_t addr)
 253 {
 254     uint8_t a,b,c,d;
 255     string_t s;
 256
 257     s=safe_malloc(16,"ipaddr_to_string");
 258     a=addr>>24;
 259     b=addr>>16;
 260     c=addr>>8;
 261     d=addr;
 262     snprintf(s, 16, "%d.%d.%d.%d", a, b, c, d);
 263     return s;
 264 }
 265
 266 string_t subnet_to_string(struct subnet *sn)
 267 {
 268     uint32_t mask=sn->mask, addr=sn->prefix;
 269     uint8_t a,b,c,d;
 270     string_t s;
 271     int i;
 272
 273     s=safe_malloc(19,"subnet_to_string");
 274     a=addr>>24;
 275     b=addr>>16;
 276     c=addr>>8;
 277     d=addr;
 278     for (i=0; mask; i++) {
 279         mask=(mask<<1);
 280     }
 281     snprintf(s, 19, "%d.%d.%d.%d/%d", a, b, c, d, i);
 282     return s;
 283 }
 284
 285 int sys_cmd(const char *path, char *arg, ...)
 286 {
 287     va_list ap;
 288     int rv;
 289     pid_t c;
 290
 291     va_start(ap,arg);
 292     c=fork();
 293     if (c) {
 294         /* Parent -> wait for child */
 295         waitpid(c,&rv,0);
 296     } else if (c==0) {
 297         char *args[100];
 298         int i;
 299         /* Child -> exec command */
 300         args[0]=arg;
 301         i=1;
 302         while ((args[i++]=va_arg(ap,char *)));
 303         execvp(path,args);
 304         exit(1);
 305     } else {
 306         /* Error */
 307         fatal_perror("sys_cmd(%s,%s,...)");
 308     }
 309
 310     va_end(ap);
 311     return rv;
 312 }
 313
 314 /* Take a list of log closures and merge them */
 315 struct loglist {
 316     struct log_if *l;
 317     struct loglist *next;
 318 };
 319
 320 static void log_vmulti(void *state, int priority, char *message, va_list args)
 321 {
 322     struct loglist *st=state, *i;
 323
 324     for (i=st; i; i=i->next) {
 325         i->l->vlog(i->l->st,priority,message,args);
 326     }
 327 }
 328
 329 static void log_multi(void *st, int priority, char *message, ...)
 330 {
 331     va_list ap;
 332
 333     va_start(ap,message);
 334
 335     log_vmulti(st,priority,message,ap);
 336
 337     va_end(ap);
 338 }
 339
 340 struct log_if *init_log(list_t *ll)
 341 {
 342     int i=0;
 343     item_t *item;
 344     closure_t *cl;
 345     struct loglist *l=NULL, *n;
 346     struct log_if *r;
 347
 348     while ((item=list_elem(ll,i++))) {
 349         if (item->type!=t_closure) {
 350             cfgfatal(item->loc,"init_log","item is not a closure");
 351         }
 352         cl=item->data.closure;
 353         if (cl->type!=CL_LOG) {
 354             cfgfatal(item->loc,"init_log","closure is not a logger");
 355         }
 356         n=safe_malloc(sizeof(*n),"init_log");
 357         n->l=cl->interface;
 358         n->next=l;
 359         l=n;
 360     }
 361     if (!l) {
 362         fatal("init_log: none of the items in the list are loggers");
 363     }
 364     r=safe_malloc(sizeof(*r), "init_log");
 365     r->st=l;
 366     r->log=log_multi;
 367     r->vlog=log_vmulti;
 368     return r;
 369 }
 370
 371 struct logfile {
 372     closure_t cl;
 373     struct log_if ops;
 374     FILE *f;
 375 };
 376
 377 static void logfile_vlog(void *state, int priority, char *message,
 378                          va_list args)
 379 {
 380     struct logfile *st=state;
 381
 382     vfprintf(st->f,message,args);
 383     fprintf(st->f,"\n");
 384 }
 385
 386 static void logfile_log(void *state, int priority, char *message, ...)
 387 {
 388     va_list ap;
 389
 390     va_start(ap,message);
 391     logfile_vlog(state,priority,message,ap);
 392     va_end(ap);
 393 }
 394
 395 static list_t *logfile_apply(closure_t *self, struct cloc loc, dict_t *context,
 396                              list_t *data)
 397 {
 398     struct logfile *st;
 399
 400     st=safe_malloc(sizeof(*st),"logfile_apply");
 401     st->cl.description="logfile";
 402     st->cl.type=CL_LOG;
 403     st->cl.apply=NULL;
 404     st->cl.interface=&st->ops;
 405     st->ops.st=st;
 406     st->ops.log=logfile_log;
 407     st->ops.vlog=logfile_vlog;
 408     st->f=stderr; /* XXX ignore args */
 409
 410     return new_closure(&st->cl);
 411 }
 412
 413 static char *phases[NR_PHASES]={
 414     "PHASE_INIT",
 415     "PHASE_GETOPTS",
 416     "PHASE_READCONFIG",
 417     "PHASE_SETUP",
 418     "PHASE_DROPPRIV",
 419     "PHASE_RUN",
 420     "PHASE_SHUTDOWN"
 421 };
 422
 423 void enter_phase(uint32_t new_phase)
 424 {
 425     struct phase_hook *i;
 426
 427     Message(M_DEBUG_PHASE,"entering %s... ", phases[new_phase]);
 428     current_phase=new_phase;
 429
 430     for (i=hooks[new_phase]; i; i=i->next)
 431         i->fn(i->state, new_phase);
 432     Message(M_DEBUG_PHASE,"now in %s\n",phases[new_phase]);
 433 }
 434
 435 bool_t add_hook(uint32_t phase, hook_fn *fn, void *state)
 436 {
 437     struct phase_hook *h;
 438
 439     h=safe_malloc(sizeof(*h),"add_hook");
 440     h->fn=fn;
 441     h->state=state;
 442     h->next=hooks[phase];
 443     hooks[phase]=h;
 444     return True;
 445 }
 446
 447 bool_t remove_hook(uint32_t phase, hook_fn *fn, void *state)
 448 {
 449     fatal("remove_hook: not implemented\n");
 450
 451     return False;
 452 }
 453
 454 void log(struct log_if *lf, int priority, char *message, ...)
 455 {
 456     va_list ap;
 457
 458     va_start(ap,message);
 459     lf->vlog(lf->st,priority,message,ap);
 460     va_end(ap);
 461 }
 462
 463 struct buffer {
 464     closure_t cl;
 465     struct buffer_if ops;
 466 };
 467
 468 void buffer_assert_free(struct buffer_if *buffer, string_t file, uint32_t line)
 469 {
 470     if (!buffer->free) {
 471         fatal("BUF_ASSERT_FREE, %s line %d, owned by %s\n",
 472               file,line,buffer->owner);
 473     }
 474 }
 475
 476 void buffer_assert_used(struct buffer_if *buffer, string_t file, uint32_t line)
 477 {
 478     if (buffer->free) {
 479         fatal("BUF_ASSERT_USED, %s line %d, last owned by %s\n",
 480               file,line,buffer->owner);
 481     }
 482 }
 483
 484 void buffer_init(struct buffer_if *buffer, uint32_t max_start_pad)
 485 {
 486     buffer->start=buffer->base+max_start_pad;
 487     buffer->size=0;
 488 }
 489
 490 void *buf_append(struct buffer_if *buf, uint32_t amount) {
 491     void *p;
 492     p=buf->start + buf->size;
 493     buf->size+=amount;
 494     return p;
 495 }
 496
 497 void *buf_prepend(struct buffer_if *buf, uint32_t amount) {
 498     buf->size+=amount;
 499     return buf->start-=amount;
 500 }
 501
 502 void *buf_unappend(struct buffer_if *buf, uint32_t amount) {
 503     if (buf->size < amount) return 0;
 504     return buf->start+(buf->size-=amount);
 505 }
 506
 507 void *buf_unprepend(struct buffer_if *buf, uint32_t amount) {
 508     void *p;
 509     p=buf->start;
 510     buf->start+=amount;
 511     buf->size-=amount;
 512     return p;
 513 }
 514
 515 /* Append a two-byte length and the string to the buffer. Length is in
 516    network byte order. */
 517 void buf_append_string(struct buffer_if *buf, string_t s)
 518 {
 519     uint16_t len;
 520
 521     len=strlen(s);
 522     buf_append_uint16(buf,len);
 523     memcpy(buf_append(buf,len),s,len);
 524 }
 525
 526 void buffer_new(struct buffer_if *buf, uint32_t len)
 527 {
 528     buf->free=True;
 529     buf->owner=NULL;
 530     buf->flags=0;
 531     buf->loc.file=NULL;
 532     buf->loc.line=0;
 533     buf->size=0;
 534     buf->len=len;
 535     buf->start=NULL;
 536     buf->base=safe_malloc(len,"buffer_new");
 537 }
 538
 539 static list_t *buffer_apply(closure_t *self, struct cloc loc, dict_t *context,
 540                             list_t *args)
 541 {
 542     struct buffer *st;
 543     item_t *item;
 544     dict_t *dict;
 545     bool_t lockdown=False;
 546     uint32_t len=DEFAULT_BUFFER_SIZE;
 547
 548     st=safe_malloc(sizeof(*st),"buffer_apply");
 549     st->cl.description="buffer";
 550     st->cl.type=CL_BUFFER;
 551     st->cl.apply=NULL;
 552     st->cl.interface=&st->ops;
 553
 554     /* First argument, if present, is buffer length */
 555     item=list_elem(args,0);
 556     if (item) {
 557         if (item->type!=t_number) {
 558             cfgfatal(st->ops.loc,"buffer","first parameter must be a "
 559                      "number (buffer size)\n");
 560         }
 561         len=item->data.number;
 562         if (len<MIN_BUFFER_SIZE) {
 563             cfgfatal(st->ops.loc,"buffer","ludicrously small buffer size\n");
 564         }
 565         if (len>MAX_BUFFER_SIZE) {
 566             cfgfatal(st->ops.loc,"buffer","ludicrously large buffer size\n");
 567         }
 568     }
 569     /* Second argument, if present, is a dictionary */
 570     item=list_elem(args,1);
 571     if (item) {
 572         if (item->type!=t_dict) {
 573             cfgfatal(st->ops.loc,"buffer","second parameter must be a "
 574                      "dictionary\n");
 575         }
 576         dict=item->data.dict;
 577         lockdown=dict_read_bool(dict,"lockdown",False,"buffer",st->ops.loc,
 578                                 False);
 579     }
 580
 581     buffer_new(&st->ops,len);
 582     if (lockdown) {
 583         Message(M_WARNING,"buffer: XXX lockdown\n");
 584     }
 585
 586     return new_closure(&st->cl);
 587 }
 588
 589 init_module util_module;
 590 void util_module(dict_t *dict)
 591 {
 592     add_closure(dict,"logfile",logfile_apply);
 593     add_closure(dict,"sysbuffer",buffer_apply);
 594 }