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|
/* $OpenBSD: privsep.c,v 1.17 2012/10/30 18:39:44 krw Exp $ */
/*
* Copyright (c) 2004 Henning Brauer <henning@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 MIND, USE, DATA OR PROFITS, WHETHER IN
* AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
* OF OR IN CONNECTION WITH THE USE, ABUSE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include "dhcpd.h"
#include "privsep.h"
struct buf *
buf_open(size_t len)
{
struct buf *buf;
if ((buf = calloc(1, sizeof(struct buf))) == NULL)
error("buf_open: %m");
if ((buf->buf = malloc(len)) == NULL) {
free(buf);
error("buf_open: %m");
}
buf->size = len;
return (buf);
}
void
buf_add(struct buf *buf, void *data, size_t len)
{
if (len == 0)
return;
if (buf->wpos + len > buf->size)
error("buf_add: %m");
memcpy(buf->buf + buf->wpos, data, len);
buf->wpos += len;
}
void
buf_close(int sock, struct buf *buf)
{
ssize_t n;
do {
n = write(sock, buf->buf + buf->rpos, buf->size - buf->rpos);
if (n == 0) /* connection closed */
error("buf_close (connection closed)");
if (n != -1 && n < buf->size - buf->rpos)
error("buf_close (short write): %m");
} while (n == -1 && (errno == EAGAIN || errno == EINTR));
if (n == -1)
error("buf_close: %m");
free(buf->buf);
free(buf);
}
void
buf_read(int sock, void *buf, size_t nbytes)
{
ssize_t n;
do {
n = read(sock, buf, nbytes);
if (n == 0) { /* connection closed */
#ifdef DEBUG
debug("buf_read (connection closed)");
#endif
exit(1);
}
if (n != -1 && n < nbytes)
error("buf_read (short read): %m");
} while (n == -1 && (errno == EINTR || errno == EAGAIN));
if (n == -1)
error("buf_read: %m");
}
void
dispatch_imsg(int fd)
{
struct imsg_hdr hdr;
in_addr_t *mask;
char *ifname, *contents;
size_t totlen, len;
struct iaddr *addr, *gateway;
int rdomain;
buf_read(fd, &hdr, sizeof(hdr));
switch (hdr.code) {
case IMSG_DELETE_ADDRESS:
totlen = sizeof(hdr);
ifname = NULL;
addr = NULL;
if (hdr.len < totlen + sizeof(len))
error("IMSG_DELETE_ADDRESS missing ifname length");
buf_read(fd, &len, sizeof(len));
totlen += sizeof(len);
if (len == SIZE_T_MAX) {
error("IMSG_DELETE_ADDRESS invalid ifname length");
} else if (len > 0) {
if (hdr.len < totlen + len)
error("IMSG_DELETE_ADDRESS short ifname");
if ((ifname = calloc(1, len + 1)) == NULL)
error("%m");
buf_read(fd, ifname, len);
totlen += len;
} else
error("IMSG_DELETE_ADDRESS ifname missing");
if (hdr.len < totlen + sizeof(len))
error("IMSG_DELETE_ADDRESS missing rdomain length");
buf_read(fd, &len, sizeof(len));
totlen += sizeof(len);
if (len == SIZE_T_MAX) {
error("IMSG_DELETE_ADDRESS invalid rdomain length");
} else if (len > 0) {
if (hdr.len < totlen + len)
error("IMSG_DELETE_ADDRESS short rdomain");
buf_read(fd, &rdomain, len);
totlen += len;
} else
error("IMSG_DELETE_ADDRESS rdomain missing");
if (hdr.len < totlen + sizeof(len))
error("IMSG_DELETE_ADDRESS missing addr length");
buf_read(fd, &len, sizeof(len));
totlen += sizeof(len);
if (len == SIZE_T_MAX) {
error("IMSG_DELETE_ADDRESS invalid addr");
} else if (len == sizeof(*addr)) {
if ((addr = calloc(1, len)) == NULL)
error("%m");
buf_read(fd, addr, len);
totlen += len;
} else {
error("IMSG_DELETE_ADDRESS addr missing %zu", len);
}
priv_delete_old_address(ifname, rdomain, *addr);
free(ifname);
free(addr);
break;
case IMSG_ADD_ADDRESS:
totlen = sizeof(hdr);
ifname = NULL;
addr = NULL;
mask = NULL;
if (hdr.len < totlen + sizeof(len))
error("IMSG_ADD_ADDRESS missing ifname length");
buf_read(fd, &len, sizeof(len));
totlen += sizeof(len);
if (len == SIZE_T_MAX) {
error("IMSG_ADD_ADDRESS invalid ifname length");
} else if (len > 0) {
if (hdr.len < totlen + len)
error("IMSG_ADD_ADDRESS short ifname");
if ((ifname = calloc(1, len + 1)) == NULL)
error("%m");
buf_read(fd, ifname, len);
totlen += len;
} else
error("IMSG_ADD_ADDRESS ifname missing");
if (hdr.len < totlen + sizeof(len))
error("IMSG_ADD_ADDRESS missing rdomain length");
buf_read(fd, &len, sizeof(len));
totlen += sizeof(len);
if (len == SIZE_T_MAX) {
error("IMSG_ADD_ADDRESS invalid rdomain length");
} else if (len > 0) {
if (hdr.len < totlen + len)
error("IMSG_ADD_ADDRESS short rdomain");
buf_read(fd, &rdomain, len);
totlen += len;
} else
error("IMSG_ADD_ADDRESS rdomain missing");
if (hdr.len < totlen + sizeof(len))
error("IMSG_ADD_ADDRESS missing addr length");
buf_read(fd, &len, sizeof(len));
totlen += sizeof(len);
if (len == SIZE_T_MAX) {
error("IMSG_ADD_ADDRESS invalid addr");
} else if (len == sizeof(*addr)) {
if ((addr = calloc(1, len)) == NULL)
error("%m");
buf_read(fd, addr, len);
totlen += len;
} else {
error("IMSG_ADD_ADDRESS addr missing %zu", len);
}
if (hdr.len < totlen + sizeof(len))
error("IMSG_ADD_ADDRESS missing mask length");
buf_read(fd, &len, sizeof(len));
totlen += sizeof(len);
mask = NULL;
if (len == SIZE_T_MAX) {
error("IMSG_ADD_ADDRESS invalid mask");
} else if (len == sizeof(*mask)) {
if ((mask = calloc(1, len)) == NULL)
error("%m");
buf_read(fd, mask, len);
totlen += len;
} else {
error("IMSG_ADD_ADDRESS mask missing %zu", len);
}
priv_add_new_address(ifname, rdomain, *addr, *mask);
free(ifname);
free(addr);
free(mask);
break;
case IMSG_FLUSH_ROUTES:
totlen = sizeof(hdr);
ifname = NULL;
addr = NULL;
if (hdr.len < totlen + sizeof(len))
error("IMSG_FLUSH_ROUTES missing ifname length");
buf_read(fd, &len, sizeof(len));
totlen += sizeof(len);
if (len == SIZE_T_MAX) {
error("IMSG_FLUSH_ROUTES invalid ifname length");
} else if (len > 0) {
if (hdr.len < totlen + len)
error("IMSG_FLUSH_ROUTES short ifname");
if ((ifname = calloc(1, len + 1)) == NULL)
error("%m");
buf_read(fd, ifname, len);
totlen += len;
} else
error("IMSG_FLUSH_ROUTES ifname missing");
if (hdr.len < totlen + sizeof(len))
error("IMSG_FLUSH_ROUTES missing rdomain length");
buf_read(fd, &len, sizeof(len));
totlen += sizeof(len);
if (len == SIZE_T_MAX) {
error("IMSG_FLUSH_ROUTES invalid rdomain length");
} else if (len > 0) {
if (hdr.len < totlen + len)
error("IMSG_FLUSH_ROUTES short rdomain");
buf_read(fd, &rdomain, len);
totlen += len;
} else
error("IMSG_FLUSH_ROUTES rdomain missing");
priv_flush_routes_and_arp_cache(ifname, rdomain);
free(ifname);
break;
case IMSG_ADD_DEFAULT_ROUTE:
totlen = sizeof(hdr);
ifname = NULL;
addr = NULL;
if (hdr.len < totlen + sizeof(len))
error("IMSG_ADD_DEFAULT_ROUTE missing ifname length");
buf_read(fd, &len, sizeof(len));
totlen += sizeof(len);
if (len == SIZE_T_MAX) {
error("IMSG_ADD_DEFAULT_ROUTE invalid ifname length");
} else if (len > 0) {
if (hdr.len < totlen + len)
error("IMSG_ADD_DEFAULT_ROUTE short ifname");
if ((ifname = calloc(1, len + 1)) == NULL)
error("%m");
buf_read(fd, ifname, len);
totlen += len;
} else
error("IMSG_ADD_DEFAULT_ROUTE ifname missing");
if (hdr.len < totlen + sizeof(len))
error("IMSG_ADD_DEFAULT_ROUTE missing rdomain length");
buf_read(fd, &len, sizeof(len));
totlen += sizeof(len);
if (len == SIZE_T_MAX) {
error("IMSG_ADD_DEFAULT_ROUTE invalid rdomain length");
} else if (len > 0) {
if (hdr.len < totlen + len)
error("IMSG_FLUSH_ROUTES short rdomain");
buf_read(fd, &rdomain, len);
totlen += len;
} else
error("IMSG_ADD_DEFAULT_ROUTE rdomain missing");
if (hdr.len < totlen + sizeof(len))
error("IMSG_ADD_DEFAULT_ROUTE missing addr length");
buf_read(fd, &len, sizeof(len));
totlen += sizeof(len);
if (len == SIZE_T_MAX) {
error("IMSG_ADD_DEFAULT_ROUTE invalid addr");
} else if (len == sizeof(*addr)) {
if ((addr = calloc(1, len)) == NULL)
error("%m");
buf_read(fd, addr, len);
totlen += len;
} else {
error("IMSG_ADD_DEFAULT_ROUTE addr missing %zu",
len);
}
if (hdr.len < totlen + sizeof(len))
error("IMSG_ADD_DEFAULT_ROUTE missing gateway length");
buf_read(fd, &len, sizeof(len));
totlen += sizeof(len);
gateway = NULL;
if (len == SIZE_T_MAX) {
error("IMSG_ADD_DEFAULT_ROUTE invalid gateway");
} else if (len == sizeof(*gateway)) {
if ((gateway = calloc(1, len)) == NULL)
error("%m");
buf_read(fd, gateway, len);
totlen += len;
} else {
error("IMSG_ADD_DEFAULT_ROUTE gateway missing %zu",
len);
}
priv_add_default_route(ifname, rdomain, *addr, *gateway);
free(ifname);
free(addr);
free(gateway);
break;
case IMSG_NEW_RESOLV_CONF:
totlen = sizeof(hdr);
ifname = NULL;
contents = NULL;
if (hdr.len < totlen + sizeof(len))
error("IMSG_NEW_RESOLV_CONF missing ifname length");
buf_read(fd, &len, sizeof(len));
totlen += sizeof(len);
if (len == SIZE_T_MAX) {
error("IMSG_NEW_RESOLV_CONF invalid ifname length");
} else if (len > 0) {
if (hdr.len < totlen + len)
error("IMSG_NEW_RESOLV_CONF short ifname");
if ((ifname = calloc(1, len + 1)) == NULL)
error("%m");
buf_read(fd, ifname, len);
totlen += len;
} else
error("IMSG_NEW_RESOLV_CONF ifname missing");
if (hdr.len < totlen + sizeof(len))
error("IMSG_NEW_RESOLV_CONF missing contents length");
buf_read(fd, &len, sizeof(len));
totlen += sizeof(len);
if (len == SIZE_T_MAX) {
error("IMSG_NEW_RESOLV_CONF invalid contents length");
} else if (len > 0) {
if (hdr.len < totlen + len)
error("IMSG_NEW_RESOLV_CONF short contents");
if ((contents = calloc(1, len + 1)) == NULL)
error("%m");
buf_read(fd, contents, len);
totlen += len;
} else
error("IMSG_NEW_RESOLV_CONF contents missing");
priv_new_resolv_conf(ifname, contents);
free(ifname);
free(contents);
break;
default:
error("received unknown message, code %d", hdr.code);
}
}
|
