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Remove socket.[ch] : code is merged into packet.c

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This commit is contained in:
Nicholas J. Kain 2011-06-25 10:40:41 -04:00
parent 7d206e45b6
commit 71f59d0433
5 changed files with 123 additions and 187 deletions
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4
ndhc/arp.c
View File

@ -30,10 +30,10 @@
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/time.h>
#include <fcntl.h>
#include <errno.h>
#include "arp.h"
#include "packet.h"
#include "socket.h"
#include "sys.h"
#include "ifchange.h"
#include "leasefile.h"
@ -81,7 +81,7 @@ static int arpping(struct client_state_t *cs, uint32_t test_ip,
close(arpfd);
return -1;
}
set_sock_nonblock(arpfd);
fcntl(arpfd, F_SETFL, fcntl(arpfd, F_GETFL) | O_NONBLOCK);
cs->arpFd = arpfd;
epoll_add(cs, arpfd);
}

1
ndhc/ndhc.c
View File

@ -45,7 +45,6 @@
#include "timeout.h"
#include "sys.h"
#include "ifchange.h"
#include "socket.h"
#include "arp.h"
#include "netlink.h"
#include "leasefile.h"

124
ndhc/packet.c
View File

@ -3,6 +3,7 @@
*
* (c) 2004-2011 Nicholas J. Kain <njkain at gmail dot com>
* (c) 2001 Russ Dill <Russ.Dill@asu.edu>
* Kernel BPF filter is (c) 2006, 2007 Stefan Rompf <sux@loplof.de>.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@ -24,6 +25,7 @@
#include <string.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <net/if.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/socket.h>
@ -31,18 +33,133 @@
#include <features.h>
#include <netpacket/packet.h>
#include <net/ethernet.h>
#include <linux/filter.h>
#include <time.h>
#include <errno.h>
#include "packet.h"
#include "socket.h"
#include "arp.h"
#include "ifchange.h"
#include "sys.h"
#include "log.h"
#include "io.h"
#include "options.h"
#include "strl.h"
static int set_sock_nonblock(int fd)
{
int ret = 0, flags;
flags = fcntl(fd, F_GETFL);
ret = fcntl(fd, F_SETFL, flags | O_NONBLOCK);
return ret;
}
/* Returns fd of new listen socket bound to @ip:@port on interface @inf
* on success, or -1 on failure. */
static int create_udp_listen_socket(unsigned int ip, int port, char *inf)
{
struct ifreq interface;
int fd;
struct sockaddr_in addr;
int opt = 1;
log_line("Opening listen socket on 0x%08x:%d %s", ip, port, inf);
if ((fd = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) {
log_error("create_udp_listen_socket: socket failed: %s", strerror(errno));
goto out;
}
if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof opt) == -1)
goto out_fd;
if (setsockopt(fd, SOL_SOCKET, SO_BROADCAST, &opt, sizeof opt) == -1)
goto out_fd;
/* Restrict operations to the physical device @inf */
strlcpy(interface.ifr_ifrn.ifrn_name, inf, IFNAMSIZ);
if (setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE,
&interface, sizeof interface) < 0)
goto out_fd;
set_sock_nonblock(fd);
memset(&addr, 0, sizeof addr);
addr.sin_family = AF_INET;
addr.sin_port = htons(port);
addr.sin_addr.s_addr = ip;
if (bind(fd, (struct sockaddr *)&addr, sizeof(struct sockaddr)) == -1)
goto out_fd;
return fd;
out_fd:
close(fd);
out:
return -1;
}
static int create_raw_listen_socket(int ifindex)
{
int fd;
struct sockaddr_ll sock;
/*
* Comment:
* I've selected not to see LL header, so BPF doesn't see it, too.
* The filter may also pass non-IP and non-ARP packets, but we do
* a more complete check when receiving the message in userspace.
* and filter shamelessly stolen from:
* http://www.flamewarmaster.de/software/dhcpclient/
*
* Copyright: 2006, 2007 Stefan Rompf <sux@loplof.de>.
* License: GPL v2.
*/
#define SERVER_AND_CLIENT_PORTS ((67 << 16) + 68)
static const struct sock_filter filter_instr[] = {
/* check for udp */
BPF_STMT(BPF_LD|BPF_B|BPF_ABS, 9),
BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, IPPROTO_UDP, 2, 0), /* L5, L1, is UDP? */
/* ugly check for arp on ethernet-like and IPv4 */
BPF_STMT(BPF_LD|BPF_W|BPF_ABS, 2), /* L1: */
BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, 0x08000604, 3, 4), /* L3, L4 */
/* skip IP header */
BPF_STMT(BPF_LDX|BPF_B|BPF_MSH, 0), /* L5: */
/* check udp source and destination ports */
BPF_STMT(BPF_LD|BPF_W|BPF_IND, 0),
BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, SERVER_AND_CLIENT_PORTS, 0, 1),/* L3, L4 */
/* returns */
BPF_STMT(BPF_RET|BPF_K, 0x0fffffff ), /* L3: pass */
BPF_STMT(BPF_RET|BPF_K, 0), /* L4: reject */
};
static const struct sock_fprog filter_prog = {
.len = sizeof(filter_instr) / sizeof(filter_instr[0]),
/* casting const away: */
.filter = (struct sock_filter *) filter_instr,
};
memset(&sock, 0, sizeof sock);
log_line("Opening raw socket on ifindex %d", ifindex);
if ((fd = socket(AF_PACKET, SOCK_DGRAM, htons(ETH_P_IP))) < 0) {
log_error("socket call failed: %s", strerror(errno));
return -1;
}
/* Ignoring error (kernel may lack support for this) */
if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &filter_prog,
sizeof filter_prog) >= 0)
log_line("Attached filter to raw socket fd %d", fd);
set_sock_nonblock(fd);
sock.sll_family = AF_PACKET;
sock.sll_protocol = htons(ETH_P_IP);
sock.sll_ifindex = ifindex;
if (bind(fd, (struct sockaddr *)&sock, sizeof(sock)) < 0) {
log_error("bind call failed: %s", strerror(errno));
close(fd);
return -1;
}
return fd;
}
// Read a packet from a cooked socket. Returns -1 on fatal error, -2 on
// transient error.
static int get_packet(struct dhcpMessage *packet, int fd)
@ -294,10 +411,11 @@ void change_listen_mode(struct client_state_t *cs, int new_mode)
log_line("Stopped listening for DHCP packets.");
return;
case LM_RAW:
cs->listenFd = raw_socket(client_config.ifindex);
cs->listenFd = create_raw_listen_socket(client_config.ifindex);
break;
case LM_KERNEL:
cs->listenFd = listen_socket(INADDR_ANY, DHCP_CLIENT_PORT,
cs->listenFd =
create_udp_listen_socket(INADDR_ANY, DHCP_CLIENT_PORT,
client_config.interface);
break;
}

151
ndhc/socket.c
View File

@ -1,151 +0,0 @@
/* socket.c - raw and kernel socket creation functions
* Time-stamp: <2011-03-30 23:47:03 nk>
*
* (c) 2004-2011 Nicholas J. Kain <njkain at gmail dot com>
* Kernel BPF filter is (c) 2006, 2007 Stefan Rompf <sux@loplof.de>.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <arpa/inet.h>
#include <net/if.h>
#include <errno.h>
#include <features.h>
#include <netpacket/packet.h>
#include <net/ethernet.h>
#include <linux/filter.h>
#include "log.h"
#include "strl.h"
int set_sock_nonblock(int fd)
{
int ret = 0, flags;
flags = fcntl(fd, F_GETFL);
ret = fcntl(fd, F_SETFL, flags | O_NONBLOCK);
return ret;
}
/* Returns fd of new listen socket bound to @ip:@port on interface @inf
* on success, or -1 on failure. */
int listen_socket(unsigned int ip, int port, char *inf)
{
struct ifreq interface;
int fd;
struct sockaddr_in addr;
int opt = 1;
log_line("Opening listen socket on 0x%08x:%d %s", ip, port, inf);
if ((fd = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) {
log_error("listen_socket: socket failed: %s", strerror(errno));
goto out;
}
if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof opt) == -1)
goto out_fd;
if (setsockopt(fd, SOL_SOCKET, SO_BROADCAST, &opt, sizeof opt) == -1)
goto out_fd;
/* Restrict operations to the physical device @inf */
strlcpy(interface.ifr_ifrn.ifrn_name, inf, IFNAMSIZ);
if (setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE,
&interface, sizeof interface) < 0)
goto out_fd;
set_sock_nonblock(fd);
memset(&addr, 0, sizeof addr);
addr.sin_family = AF_INET;
addr.sin_port = htons(port);
addr.sin_addr.s_addr = ip;
if (bind(fd, (struct sockaddr *)&addr, sizeof(struct sockaddr)) == -1)
goto out_fd;
return fd;
out_fd:
close(fd);
out:
return -1;
}
int raw_socket(int ifindex)
{
int fd;
struct sockaddr_ll sock;
/*
* Comment:
* I've selected not to see LL header, so BPF doesn't see it, too.
* The filter may also pass non-IP and non-ARP packets, but we do
* a more complete check when receiving the message in userspace.
* and filter shamelessly stolen from:
* http://www.flamewarmaster.de/software/dhcpclient/
*
* Copyright: 2006, 2007 Stefan Rompf <sux@loplof.de>.
* License: GPL v2.
*/
#define SERVER_AND_CLIENT_PORTS ((67 << 16) + 68)
static const struct sock_filter filter_instr[] = {
/* check for udp */
BPF_STMT(BPF_LD|BPF_B|BPF_ABS, 9),
BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, IPPROTO_UDP, 2, 0), /* L5, L1, is UDP? */
/* ugly check for arp on ethernet-like and IPv4 */
BPF_STMT(BPF_LD|BPF_W|BPF_ABS, 2), /* L1: */
BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, 0x08000604, 3, 4), /* L3, L4 */
/* skip IP header */
BPF_STMT(BPF_LDX|BPF_B|BPF_MSH, 0), /* L5: */
/* check udp source and destination ports */
BPF_STMT(BPF_LD|BPF_W|BPF_IND, 0),
BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, SERVER_AND_CLIENT_PORTS, 0, 1),/* L3, L4 */
/* returns */
BPF_STMT(BPF_RET|BPF_K, 0x0fffffff ), /* L3: pass */
BPF_STMT(BPF_RET|BPF_K, 0), /* L4: reject */
};
static const struct sock_fprog filter_prog = {
.len = sizeof(filter_instr) / sizeof(filter_instr[0]),
/* casting const away: */
.filter = (struct sock_filter *) filter_instr,
};
memset(&sock, 0, sizeof sock);
log_line("Opening raw socket on ifindex %d", ifindex);
if ((fd = socket(AF_PACKET, SOCK_DGRAM, htons(ETH_P_IP))) < 0) {
log_error("socket call failed: %s", strerror(errno));
return -1;
}
/* Ignoring error (kernel may lack support for this) */
if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &filter_prog,
sizeof filter_prog) >= 0)
log_line("Attached filter to raw socket fd %d", fd);
set_sock_nonblock(fd);
sock.sll_family = AF_PACKET;
sock.sll_protocol = htons(ETH_P_IP);
sock.sll_ifindex = ifindex;
if (bind(fd, (struct sockaddr *)&sock, sizeof(sock)) < 0) {
log_error("bind call failed: %s", strerror(errno));
close(fd);
return -1;
}
return fd;
}

30
ndhc/socket.h
View File

@ -1,30 +0,0 @@
/* socket.h - raw and kernel socket creation functions
* Time-stamp: <2011-03-30 23:47:34 nk>
*
* (c) 2004-2011 Nicholas J. Kain <njkain at gmail dot com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#ifndef SOCKET_H_
#define SOCKET_H_
#include <stdint.h>
int set_sock_nonblock(int fd);
int listen_socket(unsigned int ip, int port, char *inf);
int raw_socket(int ifindex);
#endif