linux/lib/libfreeswan/ttoprotoport.c

   1 /*
   2  * conversion from protocol/port string to protocol and port
   3  * Copyright (C) 2002 Mario Strasser <mast@gmx.net>,
   4  *                    Zuercher Hochschule Winterthur,
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the
   8  * Free Software Foundation; either version 2 of the License, or (at your
   9  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  13  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * for more details.
  15  *
  16  * RCSID $Id: ttoprotoport.c,v 1.1 2004/03/15 20:35:26 as Exp $
  17  */
  18
  19 #include "internal.h"
  20 #include "freeswan.h"
  21
  22 /*
  23  * ttoprotoport - converts from protocol/port string to protocol and port
  24  */
  25 err_t
  26 ttoprotoport(src, src_len, proto, port, has_port_wildcard)
  27 char *src;              /* input string */
  28 size_t src_len;         /* length of input string, use strlen() if 0 */
  29 u_int8_t *proto;        /* extracted protocol number */
  30 u_int16_t *port;        /* extracted port number if it exists */
  31 int *has_port_wildcard; /* set if port is %any */
  32 {
  33     char *end, *service_name;
  34     char proto_name[16];
  35     int proto_len;
  36     long int l;
  37     struct protoent *protocol;
  38     struct servent *service;
  39
  40     /* get the length of the string */
  41     if (!src_len) src_len = strlen(src);
  42
  43     /* locate delimiter '/' between protocol and port */
  44     end = strchr(src, '/');
  45     if (end != NULL) {
  46       proto_len = end - src;
  47       service_name = end + 1;
  48     } else {
  49       proto_len = src_len;
  50       service_name = src + src_len;
  51     }
  52
  53    /* copy protocol name*/
  54     memset(proto_name, '\0', sizeof(proto_name));
  55     memcpy(proto_name, src, proto_len);
  56
  57     /* extract protocol by trying to resolve it by name */
  58     protocol = getprotobyname(proto_name);
  59     if (protocol != NULL) {
  60         *proto = protocol->p_proto;
  61     }
  62     else  /* failed, now try it by number */
  63     {
  64         l = strtol(proto_name, &end, 0);
  65
  66         if (*proto_name && *end)
  67             return "<protocol> is neither a number nor a valid name";
  68
  69         if (l < 0 || l > 0xff)
  70             return "<protocol> must be between 0 and 255";
  71
  72         *proto = (u_int8_t)l;
  73     }
  74
  75     /* is there a port wildcard? */
  76     *has_port_wildcard = (strcmp(service_name, "%any") == 0);
  77
  78     if (*has_port_wildcard)
  79     {
  80         *port = 0;
  81         return NULL;
  82     }
  83
  84     /* extract port by trying to resolve it by name */
  85     service = getservbyname(service_name, NULL);
  86     if (service != NULL) {
  87         *port = ntohs(service->s_port);
  88     }
  89     else /* failed, now try it by number */
  90     {
  91         l = strtol(service_name, &end, 0);
  92
  93         if (*service_name && *end)
  94             return "<port> is neither a number nor a valid name";
  95
  96         if (l < 0 || l > 0xffff)
  97             return "<port> must be between 0 and 65535";
  98
  99         *port = (u_int16_t)l;
 100     }
 101     return NULL;
 102 }
 103