reactos/base/services/dhcp/privsep.c

   1 /*      $OpenBSD: privsep.c,v 1.7 2004/05/10 18:34:42 deraadt Exp $ */
   2
   3 /*
   4  * Copyright (c) 2004 Henning Brauer <henning@openbsd.org>
   5  *
   6  * Permission to use, copy, modify, and distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  14  * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER IN
  15  * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
  16  * OF OR IN CONNECTION WITH THE USE, ABUSE OR PERFORMANCE OF THIS SOFTWARE.
  17  */
  18
  19 #include "rosdhcp.h"
  20 #include "dhcpd.h"
  21 #include "privsep.h"
  22
  23 struct buf *
  24 buf_open(size_t len)
  25 {
  26         struct buf      *buf;
  27
  28         if ((buf = calloc(1, sizeof(struct buf))) == NULL)
  29                 return (NULL);
  30         if ((buf->buf = malloc(len)) == NULL) {
  31                 free(buf);
  32                 return (NULL);
  33         }
  34         buf->size = len;
  35
  36         return (buf);
  37 }
  38
  39 int
  40 buf_add(struct buf *buf, void *data, size_t len)
  41 {
  42         if (buf->wpos + len > buf->size)
  43                 return (-1);
  44
  45         memcpy(buf->buf + buf->wpos, data, len);
  46         buf->wpos += len;
  47         return (0);
  48 }
  49
  50 int
  51 buf_close(int sock, struct buf *buf)
  52 {
  53         ssize_t n;
  54
  55         n = write(sock, buf->buf + buf->rpos, buf->size - buf->rpos);
  56         if (n != -1)
  57                 buf->rpos += n;
  58         if (n == 0) {                   /* connection closed */
  59                 return (-1);
  60         }
  61
  62         if (buf->rpos < buf->size)
  63                 error("short write: wanted %lu got %ld bytes",
  64                     (unsigned long)buf->size, (long)buf->rpos);
  65
  66         free(buf->buf);
  67         free(buf);
  68         return (n);
  69 }
  70
  71 ssize_t
  72 buf_read(int sock, void *buf, size_t nbytes)
  73 {
  74         ssize_t n, r = 0;
  75         char *p = buf;
  76
  77         n = read(sock, p, nbytes);
  78         if (n == 0)
  79                 error("connection closed");
  80         if (n != -1) {
  81                 r += n;
  82                 p += n;
  83                 nbytes -= n;
  84         }
  85
  86         if (n == -1)
  87                 error("buf_read: %d", WSAGetLastError());
  88
  89         if (r < nbytes)
  90                 error("short read: wanted %lu got %ld bytes",
  91                     (unsigned long)nbytes, (long)r);
  92
  93         return (r);
  94 }
  95
  96 void
  97 dispatch_imsg(int fd)
  98 {
  99         struct imsg_hdr          hdr;
 100         char                    *medium, *reason, *filename,
 101                                 *servername, *prefix;
 102         size_t                   medium_len, reason_len, filename_len,
 103                                  servername_len, prefix_len, totlen;
 104         struct client_lease      lease;
 105         int                      ret, i, optlen;
 106         struct buf              *buf;
 107
 108         buf_read(fd, &hdr, sizeof(hdr));
 109
 110         switch (hdr.code) {
 111         case IMSG_SCRIPT_INIT:
 112                 if (hdr.len < sizeof(hdr) + sizeof(size_t))
 113                         error("corrupted message received");
 114                 buf_read(fd, &medium_len, sizeof(medium_len));
 115                 if (hdr.len < medium_len + sizeof(size_t) + sizeof(hdr)
 116                     + sizeof(size_t) || medium_len == SIZE_T_MAX)
 117                         error("corrupted message received");
 118                 if (medium_len > 0) {
 119                         if ((medium = calloc(1, medium_len + 1)) != NULL)
 120                              buf_read(fd, medium, medium_len);
 121                 } else
 122                         medium = NULL;
 123
 124                 buf_read(fd, &reason_len, sizeof(reason_len));
 125                 if (hdr.len < medium_len + reason_len + sizeof(hdr) ||
 126                     reason_len == SIZE_T_MAX)
 127                         error("corrupted message received");
 128                 if (reason_len > 0) {
 129                         if ((reason = calloc(1, reason_len + 1)) != NULL)
 130                             buf_read(fd, reason, reason_len);
 131                 } else
 132                         reason = NULL;
 133
 134 //              priv_script_init(reason, medium);
 135                 free(reason);
 136                 free(medium);
 137                 break;
 138         case IMSG_SCRIPT_WRITE_PARAMS:
 139                 //bzero(&lease, sizeof lease);
 140                 memset(&lease, 0, sizeof(lease));
 141                 totlen = sizeof(hdr) + sizeof(lease) + sizeof(size_t);
 142                 if (hdr.len < totlen)
 143                         error("corrupted message received");
 144                 buf_read(fd, &lease, sizeof(lease));
 145
 146                 buf_read(fd, &filename_len, sizeof(filename_len));
 147                 totlen += filename_len + sizeof(size_t);
 148                 if (hdr.len < totlen || filename_len == SIZE_T_MAX)
 149                         error("corrupted message received");
 150                 if (filename_len > 0) {
 151                         if ((filename = calloc(1, filename_len + 1)) != NULL)
 152                             buf_read(fd, filename, filename_len);
 153                 } else
 154                         filename = NULL;
 155
 156                 buf_read(fd, &servername_len, sizeof(servername_len));
 157                 totlen += servername_len + sizeof(size_t);
 158                 if (hdr.len < totlen || servername_len == SIZE_T_MAX)
 159                         error("corrupted message received");
 160                 if (servername_len > 0) {
 161                         if ((servername =
 162                             calloc(1, servername_len + 1)) != NULL)
 163                             buf_read(fd, servername, servername_len);
 164                 } else
 165                         servername = NULL;
 166
 167                 buf_read(fd, &prefix_len, sizeof(prefix_len));
 168                 totlen += prefix_len;
 169                 if (hdr.len < totlen || prefix_len == SIZE_T_MAX)
 170                         error("corrupted message received");
 171                 if (prefix_len > 0) {
 172                         if ((prefix = calloc(1, prefix_len + 1)) != NULL)
 173                              buf_read(fd, prefix, prefix_len);
 174                 } else
 175                         prefix = NULL;
 176
 177                 for (i = 0; i < 256; i++) {
 178                         totlen += sizeof(optlen);
 179                         if (hdr.len < totlen)
 180                                 error("corrupted message received");
 181                         buf_read(fd, &optlen, sizeof(optlen));
 182                         lease.options[i].data = NULL;
 183                         lease.options[i].len = optlen;
 184                         if (optlen > 0) {
 185                                 totlen += optlen;
 186                                 if (hdr.len < totlen || optlen == SIZE_T_MAX)
 187                                         error("corrupted message received");
 188                                 lease.options[i].data =
 189                                     calloc(1, optlen + 1);
 190                                 if (lease.options[i].data != NULL)
 191                                    buf_read(fd, lease.options[i].data, optlen);
 192                         }
 193                 }
 194                 lease.server_name = servername;
 195                 lease.filename = filename;
 196
 197 //              priv_script_write_params(prefix, &lease);
 198
 199                 free(servername);
 200                 free(filename);
 201                 free(prefix);
 202                 for (i = 0; i < 256; i++)
 203                         if (lease.options[i].len > 0)
 204                                 free(lease.options[i].data);
 205                 break;
 206         case IMSG_SCRIPT_GO:
 207                 if (hdr.len != sizeof(hdr))
 208                         error("corrupted message received");
 209
 210 //              ret = priv_script_go();
 211
 212                 hdr.code = IMSG_SCRIPT_GO_RET;
 213                 hdr.len = sizeof(struct imsg_hdr) + sizeof(int);
 214                 buf = buf_open(hdr.len);
 215
 216                 if (buf != NULL) {
 217                     buf_add(buf, &hdr, sizeof(hdr));
 218                     buf_add(buf, &ret, sizeof(ret));
 219                     buf_close(fd, buf);
 220                 }
 221                 break;
 222         default:
 223                 error("received unknown message, code %d", hdr.code);
 224         }
 225 }