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mirror of https://gitlab.nic.cz/labs/bird.git synced 2024-12-27 04:01:53 +00:00
bird/lib/socket.h
Alexander Zubkov 8a40bccffe BFD: Add option to accept zero checksum for IPv6 UDP packets
Some vendors do not fill the checksum for IPv6 UDP packets.
For interoperability with such implementations one can set
UDP_NO_CHECK6_RX socket option on Linux.

Thanks to Ville O for the suggestion.

Minor changes by committer.
2024-06-26 16:29:57 +02:00

183 lines
7.2 KiB
C

/*
* BIRD Socket Interface
*
* (c) 1998--2004 Martin Mares <mj@ucw.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#ifndef _BIRD_SOCKET_H_
#define _BIRD_SOCKET_H_
#include <errno.h>
#include "lib/resource.h"
#ifdef HAVE_LIBSSH
#define LIBSSH_LEGACY_0_4
#include <libssh/libssh.h>
#endif
#ifdef HAVE_LIBSSH
struct ssh_sock {
const char *username; /* (Required) SSH user name */
const char *server_hostkey_path; /* (Optional) Filepath to the SSH public key of remote side, can be knownhost file */
const char *client_privkey_path; /* (Optional) Filepath to the SSH private key of BIRD */
const char *subsystem; /* (Optional) Name of SSH subsytem */
ssh_session session; /* Internal */
ssh_channel channel; /* Internal */
int state; /* Internal */
#define SK_SSH_CONNECT 0 /* Start state */
#define SK_SSH_SERVER_KNOWN 1 /* Internal */
#define SK_SSH_USERAUTH 2 /* Internal */
#define SK_SSH_CHANNEL 3 /* Internal */
#define SK_SSH_SESSION 4 /* Internal */
#define SK_SSH_SUBSYSTEM 5 /* Internal */
#define SK_SSH_ESTABLISHED 6 /* Final state */
};
#endif
typedef struct birdsock {
resource r;
pool *pool; /* Pool where incoming connections should be allocated (for SK_xxx_PASSIVE) */
int type; /* Socket type */
int subtype; /* Socket subtype */
void *data; /* User data */
ip_addr saddr, daddr; /* IPA_NONE = unspecified */
const char *host; /* Alternative to daddr, NULL = unspecified */
uint sport, dport; /* 0 = unspecified (for IP: protocol type) */
int tos; /* TOS / traffic class, -1 = default */
int priority; /* Local socket priority, -1 = default */
int ttl; /* Time To Live, -1 = default */
u32 flags;
struct iface *iface; /* Interface; specify this for broad/multicast sockets */
struct iface *vrf; /* Related VRF instance, NULL if global */
byte *rbuf, *rpos; /* NULL=allocate automatically */
uint fast_rx; /* RX has higher priority in event loop */
uint rbsize;
int (*rx_hook)(struct birdsock *, uint size); /* NULL=receiving turned off, returns 1 to clear rx buffer */
byte *tbuf, *tpos; /* NULL=allocate automatically */
byte *ttx; /* Internal */
uint tbsize;
void (*tx_hook)(struct birdsock *);
void (*err_hook)(struct birdsock *, int); /* errno or zero if EOF */
/* Information about received datagrams (UDP, RAW), valid in rx_hook */
ip_addr faddr, laddr; /* src (From) and dst (Local) address of the datagram */
uint fport; /* src port of the datagram */
uint lifindex; /* local interface that received the datagram */
/* laddr and lifindex are valid only if SKF_LADDR_RX flag is set to request it */
int af; /* System-dependend adress family (e.g. AF_INET) */
int fd; /* System-dependent data */
int index; /* Index in poll buffer */
int rcv_ttl; /* TTL of last received datagram */
node n;
void *rbuf_alloc, *tbuf_alloc;
const char *password; /* Password for MD5 authentication */
const char *err; /* Error message */
struct ssh_sock *ssh; /* Used in SK_SSH */
} sock;
sock *sock_new(pool *); /* Allocate new socket */
#define sk_new(X) sock_new(X) /* Wrapper to avoid name collision with OpenSSL */
int sk_open(sock *); /* Open socket */
int sk_rx_ready(sock *s);
int sk_send(sock *, uint len); /* Send data, <0=err, >0=ok, 0=sleep */
int sk_send_to(sock *, uint len, ip_addr to, uint port); /* sk_send to given destination */
void sk_reallocate(sock *); /* Free and allocate tbuf & rbuf */
void sk_set_rbsize(sock *s, uint val); /* Resize RX buffer */
void sk_set_tbsize(sock *s, uint val); /* Resize TX buffer, keeping content */
void sk_set_tbuf(sock *s, void *tbuf); /* Switch TX buffer, NULL-> return to internal */
void sk_dump_all(void);
int sk_is_ipv4(sock *s); /* True if socket is IPv4 */
int sk_is_ipv6(sock *s); /* True if socket is IPv6 */
static inline int sk_tx_buffer_empty(sock *sk)
{ return sk->tbuf == sk->tpos; }
int sk_setup_multicast(sock *s); /* Prepare UDP or IP socket for multicasting */
int sk_join_group(sock *s, ip_addr maddr); /* Join multicast group on sk iface */
int sk_leave_group(sock *s, ip_addr maddr); /* Leave multicast group on sk iface */
int sk_setup_broadcast(sock *s);
int sk_set_ttl(sock *s, int ttl); /* Set transmit TTL for given socket */
int sk_set_min_ttl(sock *s, int ttl); /* Set minimal accepted TTL for given socket */
int sk_set_md5_auth(sock *s, ip_addr local, ip_addr remote, int pxlen, struct iface *ifa, const char *passwd, int setkey);
int sk_set_ipv6_checksum(sock *s, int offset);
int sk_set_icmp6_filter(sock *s, int p1, int p2);
void sk_log_error(sock *s, const char *p);
byte * sk_rx_buffer(sock *s, int *len); /* Temporary */
extern int sk_priority_control; /* Suggested priority for control traffic, should be sysdep define */
/* Socket flags */
#define SKF_V6ONLY 0x02 /* Use IPV6_V6ONLY socket option */
#define SKF_LADDR_RX 0x04 /* Report local address for RX packets */
#define SKF_TTL_RX 0x08 /* Report TTL / Hop Limit for RX packets */
#define SKF_BIND 0x10 /* Bind datagram socket to given source address */
#define SKF_HIGH_PORT 0x20 /* Choose port from high range if possible */
#define SKF_FREEBIND 0x40 /* Allow socket to bind to a nonlocal address */
#define SKF_CONNECT 0x80 /* Connect datagram socket to given dst address/port */
#define SKF_THREAD 0x100 /* Socked used in thread, Do not add to main loop */
#define SKF_TRUNCATED 0x200 /* Received packet was truncated, set by IO layer */
#define SKF_HDRINCL 0x400 /* Used internally */
#define SKF_PKTINFO 0x800 /* Used internally */
#define SKF_UDP6_NO_CSUM_RX 0x1000 /* Accept zero checksums for received UDPv6 packets */
/*
* Socket types SA SP DA DP IF TTL SendTo (?=may, -=must not, *=must)
*/
#define SK_TCP_PASSIVE 0 /* ? * - - - ? - */
#define SK_TCP_ACTIVE 1 /* ? ? * * - ? - */
#define SK_TCP 2
#define SK_UDP 3 /* ? ? ? ? ? ? ? */
#define SK_IP 5 /* ? - ? * ? ? ? */
#define SK_MAGIC 7 /* Internal use by sysdep code */
#define SK_UNIX_PASSIVE 8
#define SK_UNIX 9
#define SK_SSH_ACTIVE 10 /* - - * * - ? - DA = host */
#define SK_SSH 11
/*
* Socket subtypes
*/
#define SK_IPV4 1
#define SK_IPV6 2
/*
* For TCP/IP sockets, Address family (IPv4 or IPv6) can be specified either
* explicitly (SK_IPV4 or SK_IPV6) or implicitly (based on saddr, daddr). But
* these specifications must be consistent.
*
* For SK_UDP or SK_IP sockets setting DA/DP allows to use sk_send(), otherwise
* sk_send_to() must be used.
*
* For SK_IP sockets setting DP specifies protocol number, which is used for
* both receiving and sending.
*
* For multicast on SK_UDP or SK_IP sockets set IF and TTL, call
* sk_setup_multicast() to enable multicast on that socket, and then use
* sk_join_group() and sk_leave_group() to manage a set of received multicast
* groups.
*
* For datagram (SK_UDP, SK_IP) sockets, there are two ways to handle source
* address. The socket could be bound to it using bind() syscall, but that also
* forbids the reception of multicast packets, or the address could be set on
* per-packet basis using platform dependent options (but these are not
* available in some corner cases). The first way is used when SKF_BIND is
* specified, the second way is used otherwise.
*/
#endif