reactos/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         do {
  56                 n = write(sock, buf->buf + buf->rpos, buf->size - buf->rpos);
  57                 if (n != -1)
  58                         buf->rpos += n;
  59                 if (n == 0) {                   /* connection closed */
  60                         errno = 0;
  61                         return (-1);
  62                 }
  63         } while (n == -1 && (errno == EAGAIN || errno == EINTR));
  64
  65         if (buf->rpos < buf->size)
  66                 error("short write: wanted %lu got %ld bytes",
  67                     (unsigned long)buf->size, (long)buf->rpos);
  68
  69         free(buf->buf);
  70         free(buf);
  71         return (n);
  72 }
  73
  74 ssize_t
  75 buf_read(int sock, void *buf, size_t nbytes)
  76 {
  77         ssize_t n, r = 0;
  78         char *p = buf;
  79
  80         do {
  81                 n = read(sock, p, nbytes);
  82                 if (n == 0)
  83                         error("connection closed");
  84                 if (n != -1) {
  85                         r += n;
  86                         p += n;
  87                         nbytes -= n;
  88                 }
  89         } while (n == -1 && (errno == EINTR || errno == EAGAIN));
  90
  91         if (n == -1)
  92                 error("buf_read: %m");
  93
  94         if (r < nbytes)
  95                 error("short read: wanted %lu got %ld bytes",
  96                     (unsigned long)nbytes, (long)r);
  97
  98         return (r);
  99 }
 100
 101 void
 102 dispatch_imsg(int fd)
 103 {
 104         struct imsg_hdr          hdr;
 105         char                    *medium, *reason, *filename,
 106                                 *servername, *prefix;
 107         size_t                   medium_len, reason_len, filename_len,
 108                                  servername_len, prefix_len, totlen;
 109         struct client_lease      lease;
 110         int                      ret, i, optlen;
 111         struct buf              *buf;
 112
 113         buf_read(fd, &hdr, sizeof(hdr));
 114
 115         switch (hdr.code) {
 116         case IMSG_SCRIPT_INIT:
 117                 if (hdr.len < sizeof(hdr) + sizeof(size_t))
 118                         error("corrupted message received");
 119                 buf_read(fd, &medium_len, sizeof(medium_len));
 120                 if (hdr.len < medium_len + sizeof(size_t) + sizeof(hdr)
 121                     + sizeof(size_t) || medium_len == SIZE_T_MAX)
 122                         error("corrupted message received");
 123                 if (medium_len > 0) {
 124                         if ((medium = calloc(1, medium_len + 1)) == NULL)
 125                                 error("%m");
 126                         buf_read(fd, medium, medium_len);
 127                 } else
 128                         medium = NULL;
 129
 130                 buf_read(fd, &reason_len, sizeof(reason_len));
 131                 if (hdr.len < medium_len + reason_len + sizeof(hdr) ||
 132                     reason_len == SIZE_T_MAX)
 133                         error("corrupted message received");
 134                 if (reason_len > 0) {
 135                         if ((reason = calloc(1, reason_len + 1)) == NULL)
 136                                 error("%m");
 137                         buf_read(fd, reason, reason_len);
 138                 } else
 139                         reason = NULL;
 140
 141 //              priv_script_init(reason, medium);
 142                 free(reason);
 143                 free(medium);
 144                 break;
 145         case IMSG_SCRIPT_WRITE_PARAMS:
 146                 //bzero(&lease, sizeof lease);
 147                 memset(&lease, 0, sizeof(lease));
 148                 totlen = sizeof(hdr) + sizeof(lease) + sizeof(size_t);
 149                 if (hdr.len < totlen)
 150                         error("corrupted message received");
 151                 buf_read(fd, &lease, sizeof(lease));
 152
 153                 buf_read(fd, &filename_len, sizeof(filename_len));
 154                 totlen += filename_len + sizeof(size_t);
 155                 if (hdr.len < totlen || filename_len == SIZE_T_MAX)
 156                         error("corrupted message received");
 157                 if (filename_len > 0) {
 158                         if ((filename = calloc(1, filename_len + 1)) == NULL)
 159                                 error("%m");
 160                         buf_read(fd, filename, filename_len);
 161                 } else
 162                         filename = NULL;
 163
 164                 buf_read(fd, &servername_len, sizeof(servername_len));
 165                 totlen += servername_len + sizeof(size_t);
 166                 if (hdr.len < totlen || servername_len == SIZE_T_MAX)
 167                         error("corrupted message received");
 168                 if (servername_len > 0) {
 169                         if ((servername =
 170                             calloc(1, servername_len + 1)) == NULL)
 171                                 error("%m");
 172                         buf_read(fd, servername, servername_len);
 173                 } else
 174                         servername = NULL;
 175
 176                 buf_read(fd, &prefix_len, sizeof(prefix_len));
 177                 totlen += prefix_len;
 178                 if (hdr.len < totlen || prefix_len == SIZE_T_MAX)
 179                         error("corrupted message received");
 180                 if (prefix_len > 0) {
 181                         if ((prefix = calloc(1, prefix_len + 1)) == NULL)
 182                                 error("%m");
 183                         buf_read(fd, prefix, prefix_len);
 184                 } else
 185                         prefix = NULL;
 186
 187                 for (i = 0; i < 256; i++) {
 188                         totlen += sizeof(optlen);
 189                         if (hdr.len < totlen)
 190                                 error("corrupted message received");
 191                         buf_read(fd, &optlen, sizeof(optlen));
 192                         lease.options[i].data = NULL;
 193                         lease.options[i].len = optlen;
 194                         if (optlen > 0) {
 195                                 totlen += optlen;
 196                                 if (hdr.len < totlen || optlen == SIZE_T_MAX)
 197                                         error("corrupted message received");
 198                                 lease.options[i].data =
 199                                     calloc(1, optlen + 1);
 200                                 if (lease.options[i].data == NULL)
 201                                     error("%m");
 202                                 buf_read(fd, lease.options[i].data, optlen);
 203                         }
 204                 }
 205                 lease.server_name = servername;
 206                 lease.filename = filename;
 207
 208 //              priv_script_write_params(prefix, &lease);
 209
 210                 free(servername);
 211                 free(filename);
 212                 free(prefix);
 213                 for (i = 0; i < 256; i++)
 214                         if (lease.options[i].len > 0)
 215                                 free(lease.options[i].data);
 216                 break;
 217         case IMSG_SCRIPT_GO:
 218                 if (hdr.len != sizeof(hdr))
 219                         error("corrupted message received");
 220
 221 //              ret = priv_script_go();
 222
 223                 hdr.code = IMSG_SCRIPT_GO_RET;
 224                 hdr.len = sizeof(struct imsg_hdr) + sizeof(int);
 225                 if ((buf = buf_open(hdr.len)) == NULL)
 226                         error("buf_open: %m");
 227                 if (buf_add(buf, &hdr, sizeof(hdr)))
 228                         error("buf_add: %m");
 229                 if (buf_add(buf, &ret, sizeof(ret)))
 230                         error("buf_add: %m");
 231                 if (buf_close(fd, buf) == -1)
 232                         error("buf_close: %m");
 233                 break;
 234         default:
 235                 error("received unknown message, code %d", hdr.code);
 236         }
 237 }