IABSD.fr/src/lib/libc/net/ethers.c

Branch : - branch - master - tag -

• Show log

  Commit

• Author : millert
  Date : 2019-01-25 00:19:25
  Hash : bf198cc6
  Message : I am retiring my old email address; replace it with my OpenBSD one.

• lib/libc/net/ethers.c

• /*	$OpenBSD: ethers.c,v 1.27 2019/01/25 00:19:25 millert Exp $	*/
  
  /*
   * Copyright (c) 1998 Todd C. Miller <millert@openbsd.org>
   *
   * Permission to use, copy, modify, and distribute this software for any
   * purpose with or without fee is hereby granted, provided that the above
   * copyright notice and this permission notice appear in all copies.
   *
   * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
   * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
   * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
   * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
   * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
   * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
   */
  
  /* 
   * ethers(3) a la Sun.
   * Originally Written by Roland McGrath <roland@frob.com> 10/14/93.
   * Substantially modified by Todd C. Miller <millert@openbsd.org>
   */
  
  #include <sys/types.h>
  #include <sys/socket.h>
  #include <net/if.h>
  #include <netinet/in.h>
  #include <netinet/if_ether.h>
  #include <paths.h>
  #include <errno.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <ctype.h>
  #include <limits.h>
  
  #ifndef _PATH_ETHERS
  #define _PATH_ETHERS	"/etc/ethers"
  #endif
  
  static char * _ether_aton(const char *, struct ether_addr *);
  
  char *
  ether_ntoa(struct ether_addr *e)
  {
  	static char a[] = "xx:xx:xx:xx:xx:xx";
  
  	(void)snprintf(a, sizeof a, "%02x:%02x:%02x:%02x:%02x:%02x",
  	    e->ether_addr_octet[0], e->ether_addr_octet[1],
  	    e->ether_addr_octet[2], e->ether_addr_octet[3],
  	    e->ether_addr_octet[4], e->ether_addr_octet[5]);
  
  	return (a);
  }
  
  static char *
  _ether_aton(const char *s, struct ether_addr *e)
  {
  	int i;
  	long l;
  	char *pp;
  
  	while (isspace((unsigned char)*s))
  		s++;
  
  	/* expect 6 hex octets separated by ':' or space/NUL if last octet */
  	for (i = 0; i < 6; i++) {
  		l = strtol(s, &pp, 16);
  		if (pp == s || l > 0xFF || l < 0)
  			return (NULL);
  		if (!(*pp == ':' ||
  		    (i == 5 && (isspace((unsigned char)*pp) ||
  		    *pp == '\0'))))
  			return (NULL);
  		e->ether_addr_octet[i] = (u_char)l;
  		s = pp + 1;
  	}
  
  	/* return character after the octets ala strtol(3) */
  	return (pp);
  }
  
  struct ether_addr *
  ether_aton(const char *s)
  {
  	static struct ether_addr n;
  
  	return (_ether_aton(s, &n) ? &n : NULL);
  }
  
  int
  ether_ntohost(char *hostname, struct ether_addr *e)
  {
  	FILE *f; 
  	char buf[BUFSIZ+1], *p;
  	size_t len;
  	struct ether_addr try;
  
  	f = fopen(_PATH_ETHERS, "re");
  	if (f == NULL)
  		return (-1);
  	while ((p = fgetln(f, &len)) != NULL) {
  		if (p[len-1] == '\n')
  			len--;
  		if (len > sizeof(buf) - 2)
  			continue;
  		(void)memcpy(buf, p, len);
  		buf[len] = '\n';	/* code assumes newlines later on */
  		buf[len+1] = '\0';
  		/* A + in the file meant try YP, ignore it. */
  		if (!strncmp(buf, "+\n", sizeof(buf)))
  			continue;
  		if (ether_line(buf, &try, hostname) == 0 &&
  		    memcmp(&try, e, sizeof(try)) == 0) {
  			(void)fclose(f);
  			return (0);
  		}     
  	}
  	(void)fclose(f);
  	errno = ENOENT;
  	return (-1);
  }
  
  int
  ether_hostton(const char *hostname, struct ether_addr *e)
  {
  	FILE *f;
  	char buf[BUFSIZ+1], *p;
  	char try[HOST_NAME_MAX+1];
  	size_t len;
  
  	f = fopen(_PATH_ETHERS, "re");
  	if (f==NULL)
  		return (-1);
  
  	while ((p = fgetln(f, &len)) != NULL) {
  		if (p[len-1] == '\n')
  			len--;
  		if (len > sizeof(buf) - 2)
  			continue;
  		memcpy(buf, p, len);
  		buf[len] = '\n';	/* code assumes newlines later on */
  		buf[len+1] = '\0';
  		/* A + in the file meant try YP, ignore it. */
  		if (!strncmp(buf, "+\n", sizeof(buf)))
  			continue;
  		if (ether_line(buf, e, try) == 0 && strcmp(hostname, try) == 0) {
  			(void)fclose(f);
  			return (0);
  		}
  	}
  	(void)fclose(f);
  	errno = ENOENT;
  	return (-1);
  }
  
  int
  ether_line(const char *line, struct ether_addr *e, char *hostname)
  {
  	char *p;
  	size_t n;
  
  	/* Parse "xx:xx:xx:xx:xx:xx" */
  	if ((p = _ether_aton(line, e)) == NULL || (*p != ' ' && *p != '\t'))
  		goto bad;
  
  	/* Now get the hostname */
  	while (isspace((unsigned char)*p))
  		p++;
  	if (*p == '\0')
  		goto bad;
  	n = strcspn(p, " \t\n");
  	if (n >= HOST_NAME_MAX+1)
  		goto bad;
  	strlcpy(hostname, p, n + 1);
  	return (0);
  
  bad:
  	errno = EINVAL;
  	return (-1);
  }
  DEF_WEAK(ether_line);