busybox/networking/udhcp/d6_common.h
Denys Vlasenko ed898ed2dd udhcp6: fix releasing
Patch is based on work by tiggerswelt.net. They say:
"
We wanted udhcpc6 to release its IPv6-Addresses on
quit (-R-commandline-option) which turned out to generate once again
kind of garbage on the network-link.
We tracked this down to two issues:

 - udhcpc6 uses a variable called "srv6_buf" to send packets to
   the dhcp6-server, but this variable is never initialized correctly
   and contained kind of a garbage-address

 - The address of the dhcp6-server is usually a link-local-address,
   that requires an interface-index when using connect() on an AF_INET6-
   socket

We added an
additional parameter for ifindex to d6_send_kernel_packet() and made
d6_recv_raw_packet() to capture the address of the dhcp6-server and
forward it to its callee.
"

Three last patches together:

function                                             old     new   delta
d6_read_interface                                      -     454    +454
d6_recv_raw_packet                                     -     283    +283
option_to_env                                        249     504    +255
.rodata                                           165226  165371    +145
send_d6_discover                                     195     237     +42
send_d6_select                                       118     159     +41
send_d6_renew                                        173     186     +13
send_d6_release                                      162     173     +11
opt_req                                                -      10     +10
d6_send_kernel_packet                                304     312      +8
opt_fqdn_req                                           -       6      +6
d6_mcast_from_client_config_ifindex                   48      51      +3
d6_find_option                                        63      61      -2
udhcpc6_main                                        2416    2411      -5
static.d6_recv_raw_packet                            266       -    -266
------------------------------------------------------------------------------
(add/remove: 5/1 grow/shrink: 8/2 up/down: 1271/-273)         Total: 998 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-03-27 22:44:22 +02:00

138 lines
3.3 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Copyright (C) 2011 Denys Vlasenko.
*
* Licensed under GPLv2, see file LICENSE in this source tree.
*/
#ifndef UDHCP_D6_COMMON_H
#define UDHCP_D6_COMMON_H 1
#include <netinet/ip6.h>
PUSH_AND_SET_FUNCTION_VISIBILITY_TO_HIDDEN
/*** DHCPv6 packet ***/
/* DHCPv6 protocol. See RFC 3315 */
#define D6_MSG_SOLICIT 1
#define D6_MSG_ADVERTISE 2
#define D6_MSG_REQUEST 3
#define D6_MSG_CONFIRM 4
#define D6_MSG_RENEW 5
#define D6_MSG_REBIND 6
#define D6_MSG_REPLY 7
#define D6_MSG_RELEASE 8
#define D6_MSG_DECLINE 9
#define D6_MSG_RECONFIGURE 10
#define D6_MSG_INFORMATION_REQUEST 11
#define D6_MSG_RELAY_FORW 12
#define D6_MSG_RELAY_REPL 13
struct d6_packet {
union {
uint8_t d6_msg_type;
uint32_t d6_xid32;
} d6_u;
uint8_t d6_options[576 - sizeof(struct iphdr) - sizeof(struct udphdr) - 4
+ CONFIG_UDHCPC_SLACK_FOR_BUGGY_SERVERS];
} PACKED;
#define d6_msg_type d6_u.d6_msg_type
#define d6_xid32 d6_u.d6_xid32
struct ip6_udp_d6_packet {
struct ip6_hdr ip6;
struct udphdr udp;
struct d6_packet data;
} PACKED;
struct udp_d6_packet {
struct udphdr udp;
struct d6_packet data;
} PACKED;
/*** Options ***/
struct d6_option {
uint8_t code_hi;
uint8_t code;
uint8_t len_hi;
uint8_t len;
uint8_t data[1];
} PACKED;
#define D6_OPT_CLIENTID 1
#define D6_OPT_SERVERID 2
#define D6_OPT_IA_NA 3
#define D6_OPT_IA_TA 4
#define D6_OPT_IAADDR 5
#define D6_OPT_ORO 6
#define D6_OPT_PREFERENCE 7
#define D6_OPT_ELAPSED_TIME 8
#define D6_OPT_RELAY_MSG 9
#define D6_OPT_AUTH 11
#define D6_OPT_UNICAST 12
#define D6_OPT_STATUS_CODE 13
#define D6_OPT_RAPID_COMMIT 14
#define D6_OPT_USER_CLASS 15
#define D6_OPT_VENDOR_CLASS 16
#define D6_OPT_VENDOR_OPTS 17
#define D6_OPT_INTERFACE_ID 18
#define D6_OPT_RECONF_MSG 19
#define D6_OPT_RECONF_ACCEPT 20
#define D6_OPT_DNS_SERVERS 23
#define D6_OPT_DOMAIN_LIST 24
#define D6_OPT_IA_PD 25
#define D6_OPT_IAPREFIX 26
#define D6_OPT_CLIENT_FQDN 39
/*** Other shared functions ***/
struct client6_data_t {
struct d6_option *server_id;
struct d6_option *ia_na;
char **env_ptr;
unsigned env_idx;
/* link-local IPv6 address */
struct in6_addr ll_ip6;
};
#define client6_data (*(struct client6_data_t*)(&bb_common_bufsiz1[COMMON_BUFSIZE - sizeof(struct client6_data_t)]))
int FAST_FUNC d6_read_interface(const char *interface, int *ifindex, struct in6_addr *nip6, uint8_t *mac);
int FAST_FUNC d6_listen_socket(int port, const char *inf);
int FAST_FUNC d6_recv_kernel_packet(
struct in6_addr *peer_ipv6,
struct d6_packet *packet, int fd
);
int FAST_FUNC d6_send_raw_packet(
struct d6_packet *d6_pkt, unsigned d6_pkt_size,
struct in6_addr *src_ipv6, int source_port,
struct in6_addr *dst_ipv6, int dest_port, const uint8_t *dest_arp,
int ifindex
);
int FAST_FUNC d6_send_kernel_packet(
struct d6_packet *d6_pkt, unsigned d6_pkt_size,
struct in6_addr *src_ipv6, int source_port,
struct in6_addr *dst_ipv6, int dest_port,
int ifindex
);
#if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 2
void FAST_FUNC d6_dump_packet(struct d6_packet *packet);
#else
# define d6_dump_packet(packet) ((void)0)
#endif
POP_SAVED_FUNCTION_VISIBILITY
#endif