lib/socket.h

   1 /*
   2  *      BIRD Socket Interface
   3  *
   4  *      (c) 1998--2004 Martin Mares <mj@ucw.cz>
   5  *
   6  *      Can be freely distributed and used under the terms of the GNU GPL.
   7  */
   8
   9 #ifndef _BIRD_SOCKET_H_
  10 #define _BIRD_SOCKET_H_
  11
  12 #include <errno.h>
  13 // #include <sys/socket.h>
  14
  15 #include "lib/resource.h"
  16
  17 typedef struct birdsock {
  18   resource r;
  19   pool *pool;                           /* Pool where incoming connections should be allocated (for SK_xxx_PASSIVE) */
  20   int type;                             /* Socket type */
  21   void *data;                           /* User data */
  22   ip_addr saddr, daddr;                 /* IPA_NONE = unspecified */
  23   uint sport, dport;                    /* 0 = unspecified (for IP: protocol type) */
  24   int tos;                              /* TOS / traffic class, -1 = default */
  25   int priority;                         /* Local socket priority, -1 = default */
  26   int ttl;                              /* Time To Live, -1 = default */
  27   u32 flags;
  28   struct iface *iface;                  /* Interface; specify this for broad/multicast sockets */
  29   struct iface *vrf;                    /* Related VRF instance, NULL if global */
  30
  31   byte *rbuf, *rpos;                    /* NULL=allocate automatically */
  32   uint fast_rx;                         /* RX has higher priority in event loop */
  33   uint rbsize;
  34   int (*rx_hook)(struct birdsock *, uint size); /* NULL=receiving turned off, returns 1 to clear rx buffer */
  35
  36   byte *tbuf, *tpos;                    /* NULL=allocate automatically */
  37   byte *ttx;                            /* Internal */
  38   uint tbsize;
  39   void (*tx_hook)(struct birdsock *);
  40
  41   void (*err_hook)(struct birdsock *, int); /* errno or zero if EOF */
  42
  43   /* Information about received datagrams (UDP, RAW), valid in rx_hook */
  44   ip_addr faddr, laddr;                 /* src (From) and dst (Local) address of the datagram */
  45   uint fport;                           /* src port of the datagram */
  46   uint lifindex;                        /* local interface that received the datagram */
  47   /* laddr and lifindex are valid only if SKF_LADDR_RX flag is set to request it */
  48
  49   int af;                               /* Address family (AF_INET, AF_INET6 or 0 for non-IP) of fd */
  50   int fd;                               /* System-dependent data */
  51   int index;                            /* Index in poll buffer */
  52   int rcv_ttl;                          /* TTL of last received datagram */
  53   node n;
  54   void *rbuf_alloc, *tbuf_alloc;
  55   char *password;                       /* Password for MD5 authentication */
  56   char *err;                            /* Error message */
  57 } sock;
  58
  59 sock *sock_new(pool *);                 /* Allocate new socket */
  60 #define sk_new(X) sock_new(X)           /* Wrapper to avoid name collision with OpenSSL */
  61
  62 int sk_open(sock *);                    /* Open socket */
  63 int sk_rx_ready(sock *s);
  64 int sk_send(sock *, uint len);          /* Send data, <0=err, >0=ok, 0=sleep */
  65 int sk_send_to(sock *, uint len, ip_addr to, uint port); /* sk_send to given destination */
  66 void sk_reallocate(sock *);             /* Free and allocate tbuf & rbuf */
  67 void sk_set_rbsize(sock *s, uint val);  /* Resize RX buffer */
  68 void sk_set_tbsize(sock *s, uint val);  /* Resize TX buffer, keeping content */
  69 void sk_set_tbuf(sock *s, void *tbuf);  /* Switch TX buffer, NULL-> return to internal */
  70 void sk_dump_all(void);
  71
  72 static inline int sk_send_buffer_empty(sock *sk)
  73 { return sk->tbuf == sk->tpos; }
  74
  75
  76 #ifdef IPV6
  77 #define sk_is_ipv4(X) 0
  78 #define sk_is_ipv6(X) 1
  79 #else
  80 #define sk_is_ipv4(X) 1
  81 #define sk_is_ipv6(X) 0
  82 #endif
  83
  84
  85 int sk_setup_multicast(sock *s);        /* Prepare UDP or IP socket for multicasting */
  86 int sk_join_group(sock *s, ip_addr maddr);      /* Join multicast group on sk iface */
  87 int sk_leave_group(sock *s, ip_addr maddr);     /* Leave multicast group on sk iface */
  88 int sk_setup_broadcast(sock *s);
  89 int sk_set_ttl(sock *s, int ttl);       /* Set transmit TTL for given socket */
  90 int sk_set_min_ttl(sock *s, int ttl);   /* Set minimal accepted TTL for given socket */
  91 int sk_set_md5_auth(sock *s, ip_addr local, ip_addr remote, struct iface *ifa, char *passwd, int setkey);
  92 int sk_set_ipv6_checksum(sock *s, int offset);
  93 int sk_set_icmp6_filter(sock *s, int p1, int p2);
  94 void sk_log_error(sock *s, const char *p);
  95
  96 byte * sk_rx_buffer(sock *s, int *len); /* Temporary */
  97
  98 extern int sk_priority_control;         /* Suggested priority for control traffic, should be sysdep define */
  99
 100
 101 /* Socket flags */
 102
 103 #define SKF_V4ONLY      0x01    /* Use IPv4 for IP sockets */
 104 #define SKF_V6ONLY      0x02    /* Use IPV6_V6ONLY socket option */
 105 #define SKF_LADDR_RX    0x04    /* Report local address for RX packets */
 106 #define SKF_TTL_RX      0x08    /* Report TTL / Hop Limit for RX packets */
 107 #define SKF_BIND        0x10    /* Bind datagram socket to given source address */
 108 #define SKF_HIGH_PORT   0x20    /* Choose port from high range if possible */
 109
 110 #define SKF_THREAD      0x100   /* Socked used in thread, Do not add to main loop */
 111 #define SKF_TRUNCATED   0x200   /* Received packet was truncated, set by IO layer */
 112 #define SKF_HDRINCL     0x400   /* Used internally */
 113 #define SKF_PKTINFO     0x800   /* Used internally */
 114
 115 /*
 116  *      Socket types                 SA SP DA DP IF  TTL SendTo (?=may, -=must not, *=must)
 117  */
 118
 119 #define SK_TCP_PASSIVE  0          /* ?  *  -  -  -  ?   -      */
 120 #define SK_TCP_ACTIVE   1          /* ?  ?  *  *  -  ?   -      */
 121 #define SK_TCP          2
 122 #define SK_UDP          3          /* ?  ?  ?  ?  ?  ?   ?      */
 123 #define SK_IP           5          /* ?  -  ?  *  ?  ?   ?      */
 124 #define SK_MAGIC        7          /* Internal use by sysdep code */
 125 #define SK_UNIX_PASSIVE 8
 126 #define SK_UNIX         9
 127
 128 /*
 129  *  For SK_UDP or SK_IP sockets setting DA/DP allows to use sk_send(),
 130  *  otherwise sk_send_to() must be used.
 131  *
 132  *  For SK_IP sockets setting DP specifies protocol number, which is used
 133  *  for both receiving and sending.
 134  *
 135  *  For multicast on SK_UDP or SK_IP sockets set IF and TTL,
 136  *  call sk_setup_multicast() to enable multicast on that socket,
 137  *  and then use sk_join_group() and sk_leave_group() to manage
 138  *  a set of received multicast groups.
 139  *
 140  *  For datagram (SK_UDP, SK_IP) sockets, there are two ways to handle
 141  *  source address. The socket could be bound to it using bind()
 142  *  syscall, but that also forbids the reception of multicast packets,
 143  *  or the address could be set on per-packet basis using platform
 144  *  dependent options (but these are not available in some corner
 145  *  cases). The first way is used when SKF_BIND is specified, the
 146  *  second way is used otherwise.
 147  */
 148
 149 #endif