include/net.h

   1 /*
   2  *      LiMon Monitor (LiMon) - Network.
   3  *
   4  *      Copyright 1994 - 2000 Neil Russell.
   5  *      (See License)
   6  *
   7  *
   8  * History
   9  *      9/16/00   bor  adapted to TQM823L/STK8xxL board, RARP/TFTP boot added
  10  */
  11
  12 #ifndef __NET_H__
  13 #define __NET_H__
  14
  15 #if defined(CONFIG_8xx)
  16 #include <commproc.h>
  17 #endif  /* CONFIG_8xx */
  18
  19 #include <asm/cache.h>
  20 #include <asm/byteorder.h>      /* for nton* / ntoh* stuff */
  21
  22
  23 /*
  24  *      The number of receive packet buffers, and the required packet buffer
  25  *      alignment in memory.
  26  *
  27  */
  28
  29 #ifdef CONFIG_SYS_RX_ETH_BUFFER
  30 # define PKTBUFSRX      CONFIG_SYS_RX_ETH_BUFFER
  31 #else
  32 # define PKTBUFSRX      4
  33 #endif
  34
  35 #define PKTALIGN        ARCH_DMA_MINALIGN
  36
  37 /* IPv4 addresses are always 32 bits in size */
  38 typedef u32             IPaddr_t;
  39
  40
  41 /**
  42  * An incoming packet handler.
  43  * @param pkt    pointer to the application packet
  44  * @param dport  destination UDP port
  45  * @param sip    source IP address
  46  * @param sport  source UDP port
  47  * @param len    packet length
  48  */
  49 typedef void rxhand_f(uchar *pkt, unsigned dport,
  50                       IPaddr_t sip, unsigned sport,
  51                       unsigned len);
  52
  53 /**
  54  * An incoming ICMP packet handler.
  55  * @param type  ICMP type
  56  * @param code  ICMP code
  57  * @param dport destination UDP port
  58  * @param sip   source IP address
  59  * @param sport source UDP port
  60  * @param pkt   pointer to the ICMP packet data
  61  * @param len   packet length
  62  */
  63 typedef void rxhand_icmp_f(unsigned type, unsigned code, unsigned dport,
  64                 IPaddr_t sip, unsigned sport, uchar *pkt, unsigned len);
  65
  66 /*
  67  *      A timeout handler.  Called after time interval has expired.
  68  */
  69 typedef void    thand_f(void);
  70
  71 enum eth_state_t {
  72         ETH_STATE_INIT,
  73         ETH_STATE_PASSIVE,
  74         ETH_STATE_ACTIVE
  75 };
  76
  77 struct eth_device {
  78         char name[16];
  79         unsigned char enetaddr[6];
  80         int iobase;
  81         int state;
  82
  83         int  (*init) (struct eth_device *, bd_t *);
  84         int  (*send) (struct eth_device *, void *packet, int length);
  85         int  (*recv) (struct eth_device *);
  86         void (*halt) (struct eth_device *);
  87 #ifdef CONFIG_MCAST_TFTP
  88         int (*mcast) (struct eth_device *, u32 ip, u8 set);
  89 #endif
  90         int  (*write_hwaddr) (struct eth_device *);
  91         struct eth_device *next;
  92         int index;
  93         void *priv;
  94 };
  95
  96 extern int eth_initialize(bd_t *bis);   /* Initialize network subsystem */
  97 extern int eth_register(struct eth_device* dev);/* Register network device */
  98 extern int eth_unregister(struct eth_device *dev);/* Remove network device */
  99 extern void eth_try_another(int first_restart); /* Change the device */
 100 extern void eth_set_current(void);              /* set nterface to ethcur var */
 101 extern struct eth_device *eth_get_dev(void);    /* get the current device MAC */
 102 extern struct eth_device *eth_get_dev_by_name(const char *devname);
 103 extern struct eth_device *eth_get_dev_by_index(int index); /* get dev @ index */
 104 extern int eth_get_dev_index(void);             /* get the device index */
 105 extern void eth_parse_enetaddr(const char *addr, uchar *enetaddr);
 106 extern int eth_getenv_enetaddr(char *name, uchar *enetaddr);
 107 extern int eth_setenv_enetaddr(char *name, const uchar *enetaddr);
 108
 109 /*
 110  * Get the hardware address for an ethernet interface .
 111  * Args:
 112  *      base_name - base name for device (normally "eth")
 113  *      index - device index number (0 for first)
 114  *      enetaddr - returns 6 byte hardware address
 115  * Returns:
 116  *      Return true if the address is valid.
 117  */
 118 extern int eth_getenv_enetaddr_by_index(const char *base_name, int index,
 119                                         uchar *enetaddr);
 120
 121 extern int usb_eth_initialize(bd_t *bi);
 122 extern int eth_init(bd_t *bis);                 /* Initialize the device */
 123 extern int eth_send(void *packet, int length);     /* Send a packet */
 124
 125 #ifdef CONFIG_API
 126 extern int eth_receive(void *packet, int length); /* Receive a packet*/
 127 extern void (*push_packet)(void *packet, int length);
 128 #endif
 129 extern int eth_rx(void);                        /* Check for received packets */
 130 extern void eth_halt(void);                     /* stop SCC */
 131 extern char *eth_get_name(void);                /* get name of current device */
 132
 133 /*
 134  * Set the hardware address for an ethernet interface based on 'eth%daddr'
 135  * environment variable (or just 'ethaddr' if eth_number is 0).
 136  * Args:
 137  *      base_name - base name for device (normally "eth")
 138  *      eth_number - value of %d (0 for first device of this type)
 139  * Returns:
 140  *      0 is success, non-zero is error status from driver.
 141  */
 142 int eth_write_hwaddr(struct eth_device *dev, const char *base_name,
 143                      int eth_number);
 144
 145 #ifdef CONFIG_MCAST_TFTP
 146 int eth_mcast_join(IPaddr_t mcast_addr, u8 join);
 147 u32 ether_crc(size_t len, unsigned char const *p);
 148 #endif
 149
 150
 151 /**********************************************************************/
 152 /*
 153  *      Protocol headers.
 154  */
 155
 156 /*
 157  *      Ethernet header
 158  */
 159
 160 struct ethernet_hdr {
 161         uchar           et_dest[6];     /* Destination node             */
 162         uchar           et_src[6];      /* Source node                  */
 163         ushort          et_protlen;     /* Protocol or length           */
 164 };
 165
 166 /* Ethernet header size */
 167 #define ETHER_HDR_SIZE  (sizeof(struct ethernet_hdr))
 168
 169 struct e802_hdr {
 170         uchar           et_dest[6];     /* Destination node             */
 171         uchar           et_src[6];      /* Source node                  */
 172         ushort          et_protlen;     /* Protocol or length           */
 173         uchar           et_dsap;        /* 802 DSAP                     */
 174         uchar           et_ssap;        /* 802 SSAP                     */
 175         uchar           et_ctl;         /* 802 control                  */
 176         uchar           et_snap1;       /* SNAP                         */
 177         uchar           et_snap2;
 178         uchar           et_snap3;
 179         ushort          et_prot;        /* 802 protocol                 */
 180 };
 181
 182 /* 802 ethernet header size */
 183 #define E802_HDR_SIZE   (sizeof(struct e802_hdr))
 184
 185 /*
 186  *      Ethernet header
 187  */
 188 struct vlan_ethernet_hdr {
 189         uchar           vet_dest[6];    /* Destination node             */
 190         uchar           vet_src[6];     /* Source node                  */
 191         ushort          vet_vlan_type;  /* PROT_VLAN                    */
 192         ushort          vet_tag;        /* TAG of VLAN                  */
 193         ushort          vet_type;       /* protocol type                */
 194 };
 195
 196 /* VLAN Ethernet header size */
 197 #define VLAN_ETHER_HDR_SIZE     (sizeof(struct vlan_ethernet_hdr))
 198
 199 #define PROT_IP         0x0800          /* IP protocol                  */
 200 #define PROT_ARP        0x0806          /* IP ARP protocol              */
 201 #define PROT_RARP       0x8035          /* IP ARP protocol              */
 202 #define PROT_VLAN       0x8100          /* IEEE 802.1q protocol         */
 203
 204 #define IPPROTO_ICMP     1      /* Internet Control Message Protocol    */
 205 #define IPPROTO_UDP     17      /* User Datagram Protocol               */
 206
 207 /*
 208  *      Internet Protocol (IP) header.
 209  */
 210 struct ip_hdr {
 211         uchar           ip_hl_v;        /* header length and version    */
 212         uchar           ip_tos;         /* type of service              */
 213         ushort          ip_len;         /* total length                 */
 214         ushort          ip_id;          /* identification               */
 215         ushort          ip_off;         /* fragment offset field        */
 216         uchar           ip_ttl;         /* time to live                 */
 217         uchar           ip_p;           /* protocol                     */
 218         ushort          ip_sum;         /* checksum                     */
 219         IPaddr_t        ip_src;         /* Source IP address            */
 220         IPaddr_t        ip_dst;         /* Destination IP address       */
 221 };
 222
 223 #define IP_OFFS         0x1fff /* ip offset *= 8 */
 224 #define IP_FLAGS        0xe000 /* first 3 bits */
 225 #define IP_FLAGS_RES    0x8000 /* reserved */
 226 #define IP_FLAGS_DFRAG  0x4000 /* don't fragments */
 227 #define IP_FLAGS_MFRAG  0x2000 /* more fragments */
 228
 229 #define IP_HDR_SIZE             (sizeof(struct ip_hdr))
 230
 231 /*
 232  *      Internet Protocol (IP) + UDP header.
 233  */
 234 struct ip_udp_hdr {
 235         uchar           ip_hl_v;        /* header length and version    */
 236         uchar           ip_tos;         /* type of service              */
 237         ushort          ip_len;         /* total length                 */
 238         ushort          ip_id;          /* identification               */
 239         ushort          ip_off;         /* fragment offset field        */
 240         uchar           ip_ttl;         /* time to live                 */
 241         uchar           ip_p;           /* protocol                     */
 242         ushort          ip_sum;         /* checksum                     */
 243         IPaddr_t        ip_src;         /* Source IP address            */
 244         IPaddr_t        ip_dst;         /* Destination IP address       */
 245         ushort          udp_src;        /* UDP source port              */
 246         ushort          udp_dst;        /* UDP destination port         */
 247         ushort          udp_len;        /* Length of UDP packet         */
 248         ushort          udp_xsum;       /* Checksum                     */
 249 };
 250
 251 #define IP_UDP_HDR_SIZE         (sizeof(struct ip_udp_hdr))
 252 #define UDP_HDR_SIZE            (IP_UDP_HDR_SIZE - IP_HDR_SIZE)
 253
 254 /*
 255  *      Address Resolution Protocol (ARP) header.
 256  */
 257 struct arp_hdr {
 258         ushort          ar_hrd;         /* Format of hardware address   */
 259 #   define ARP_ETHER        1           /* Ethernet  hardware address   */
 260         ushort          ar_pro;         /* Format of protocol address   */
 261         uchar           ar_hln;         /* Length of hardware address   */
 262         uchar           ar_pln;         /* Length of protocol address   */
 263         ushort          ar_op;          /* Operation                    */
 264 #   define ARPOP_REQUEST    1           /* Request  to resolve  address */
 265 #   define ARPOP_REPLY      2           /* Response to previous request */
 266
 267 #   define RARPOP_REQUEST   3           /* Request  to resolve  address */
 268 #   define RARPOP_REPLY     4           /* Response to previous request */
 269
 270         /*
 271          * The remaining fields are variable in size, according to
 272          * the sizes above, and are defined as appropriate for
 273          * specific hardware/protocol combinations.
 274          */
 275         uchar           ar_data[0];
 276 #if 0
 277         uchar           ar_sha[];       /* Sender hardware address      */
 278         uchar           ar_spa[];       /* Sender protocol address      */
 279         uchar           ar_tha[];       /* Target hardware address      */
 280         uchar           ar_tpa[];       /* Target protocol address      */
 281 #endif /* 0 */
 282 };
 283
 284 #define ARP_HDR_SIZE    (8+20)          /* Size assuming ethernet       */
 285
 286 /*
 287  * ICMP stuff (just enough to handle (host) redirect messages)
 288  */
 289 #define ICMP_ECHO_REPLY         0       /* Echo reply                   */
 290 #define ICMP_NOT_REACH          3       /* Detination unreachable       */
 291 #define ICMP_REDIRECT           5       /* Redirect (change route)      */
 292 #define ICMP_ECHO_REQUEST       8       /* Echo request                 */
 293
 294 /* Codes for REDIRECT. */
 295 #define ICMP_REDIR_NET          0       /* Redirect Net                 */
 296 #define ICMP_REDIR_HOST         1       /* Redirect Host                */
 297
 298 /* Codes for NOT_REACH */
 299 #define ICMP_NOT_REACH_PORT     3       /* Port unreachable             */
 300
 301 struct icmp_hdr {
 302         uchar           type;
 303         uchar           code;
 304         ushort          checksum;
 305         union {
 306                 struct {
 307                         ushort  id;
 308                         ushort  sequence;
 309                 } echo;
 310                 ulong   gateway;
 311                 struct {
 312                         ushort  __unused;
 313                         ushort  mtu;
 314                 } frag;
 315                 uchar data[0];
 316         } un;
 317 };
 318
 319 #define ICMP_HDR_SIZE           (sizeof(struct icmp_hdr))
 320 #define IP_ICMP_HDR_SIZE        (IP_HDR_SIZE + ICMP_HDR_SIZE)
 321
 322 /*
 323  * Maximum packet size; used to allocate packet storage.
 324  * TFTP packets can be 524 bytes + IP header + ethernet header.
 325  * Lets be conservative, and go for 38 * 16.  (Must also be
 326  * a multiple of 32 bytes).
 327  */
 328 /*
 329  * AS.HARNOIS : Better to set PKTSIZE to maximum size because
 330  * traffic type is not always controlled
 331  * maximum packet size =  1518
 332  * maximum packet size and multiple of 32 bytes =  1536
 333  */
 334 #define PKTSIZE                 1518
 335 #define PKTSIZE_ALIGN           1536
 336 /*#define PKTSIZE               608*/
 337
 338 /*
 339  * Maximum receive ring size; that is, the number of packets
 340  * we can buffer before overflow happens. Basically, this just
 341  * needs to be enough to prevent a packet being discarded while
 342  * we are processing the previous one.
 343  */
 344 #define RINGSZ          4
 345 #define RINGSZ_LOG2     2
 346
 347 /**********************************************************************/
 348 /*
 349  *      Globals.
 350  *
 351  * Note:
 352  *
 353  * All variables of type IPaddr_t are stored in NETWORK byte order
 354  * (big endian).
 355  */
 356
 357 /* net.c */
 358 /** BOOTP EXTENTIONS **/
 359 extern IPaddr_t NetOurGatewayIP;        /* Our gateway IP address */
 360 extern IPaddr_t NetOurSubnetMask;       /* Our subnet mask (0 = unknown) */
 361 extern IPaddr_t NetOurDNSIP;    /* Our Domain Name Server (0 = unknown) */
 362 #if defined(CONFIG_BOOTP_DNS2)
 363 extern IPaddr_t NetOurDNS2IP;   /* Our 2nd Domain Name Server (0 = unknown) */
 364 #endif
 365 extern char     NetOurNISDomain[32];    /* Our NIS domain */
 366 extern char     NetOurHostName[32];     /* Our hostname */
 367 extern char     NetOurRootPath[64];     /* Our root path */
 368 extern ushort   NetBootFileSize;        /* Our boot file size in blocks */
 369 /** END OF BOOTP EXTENTIONS **/
 370 extern ulong            NetBootFileXferSize;    /* size of bootfile in bytes */
 371 extern uchar            NetOurEther[6];         /* Our ethernet address */
 372 extern uchar            NetServerEther[6];      /* Boot server enet address */
 373 extern IPaddr_t         NetOurIP;       /* Our    IP addr (0 = unknown) */
 374 extern IPaddr_t         NetServerIP;    /* Server IP addr (0 = unknown) */
 375 extern uchar            *NetTxPacket;           /* THE transmit packet */
 376 extern uchar            *NetRxPackets[PKTBUFSRX]; /* Receive packets */
 377 extern uchar            *NetRxPacket;           /* Current receive packet */
 378 extern int              NetRxPacketLen;         /* Current rx packet length */
 379 extern unsigned         NetIPID;                /* IP ID (counting) */
 380 extern uchar            NetBcastAddr[6];        /* Ethernet boardcast address */
 381 extern uchar            NetEtherNullAddr[6];
 382
 383 #define VLAN_NONE       4095                    /* untagged */
 384 #define VLAN_IDMASK     0x0fff                  /* mask of valid vlan id */
 385 extern ushort           NetOurVLAN;             /* Our VLAN */
 386 extern ushort           NetOurNativeVLAN;       /* Our Native VLAN */
 387
 388 extern int              NetState;               /* Network loop state */
 389 #define NETLOOP_CONTINUE        1
 390 #define NETLOOP_RESTART         2
 391 #define NETLOOP_SUCCESS         3
 392 #define NETLOOP_FAIL            4
 393
 394 extern int              NetRestartWrap;         /* Tried all network devices */
 395
 396 enum proto_t {
 397         BOOTP, RARP, ARP, TFTPGET, DHCP, PING, DNS, NFS, CDP, NETCONS, SNTP,
 398         TFTPSRV, TFTPPUT
 399 };
 400
 401 /* from net/net.c */
 402 extern char     BootFile[128];                  /* Boot File name */
 403
 404 #if defined(CONFIG_CMD_DNS)
 405 extern char *NetDNSResolve;             /* The host to resolve  */
 406 extern char *NetDNSenvvar;              /* the env var to put the ip into */
 407 #endif
 408
 409 #if defined(CONFIG_CMD_PING)
 410 extern IPaddr_t NetPingIP;                      /* the ip address to ping */
 411 #endif
 412
 413 #if defined(CONFIG_CMD_CDP)
 414 /* when CDP completes these hold the return values */
 415 extern ushort CDPNativeVLAN;            /* CDP returned native VLAN */
 416 extern ushort CDPApplianceVLAN;         /* CDP returned appliance VLAN */
 417
 418 /*
 419  * Check for a CDP packet by examining the received MAC address field
 420  */
 421 static inline int is_cdp_packet(const uchar *et_addr)
 422 {
 423         extern const uchar NetCDPAddr[6];
 424
 425         return memcmp(et_addr, NetCDPAddr, 6) == 0;
 426 }
 427 #endif
 428
 429 #if defined(CONFIG_CMD_SNTP)
 430 extern IPaddr_t NetNtpServerIP;                 /* the ip address to NTP */
 431 extern int NetTimeOffset;                       /* offset time from UTC */
 432 #endif
 433
 434 #if defined(CONFIG_MCAST_TFTP)
 435 extern IPaddr_t Mcast_addr;
 436 #endif
 437
 438 /* Initialize the network adapter */
 439 extern int NetLoop(enum proto_t);
 440
 441 /* Shutdown adapters and cleanup */
 442 extern void     NetStop(void);
 443
 444 /* Load failed.  Start again. */
 445 extern void     NetStartAgain(void);
 446
 447 /* Get size of the ethernet header when we send */
 448 extern int      NetEthHdrSize(void);
 449
 450 /* Set ethernet header; returns the size of the header */
 451 extern int NetSetEther(uchar *, uchar *, uint);
 452
 453 /* Set IP header */
 454 extern void NetSetIP(uchar *, IPaddr_t, int, int, int);
 455
 456 /* Checksum */
 457 extern int      NetCksumOk(uchar *, int);       /* Return true if cksum OK */
 458 extern uint     NetCksum(uchar *, int);         /* Calculate the checksum */
 459
 460 /* Callbacks */
 461 extern rxhand_f *NetGetHandler(void);           /* Get RX packet handler */
 462 extern void     NetSetHandler(rxhand_f *);      /* Set RX packet handler */
 463 extern void net_set_icmp_handler(rxhand_icmp_f *f); /* Set ICMP RX handler */
 464 extern void     NetSetTimeout(ulong, thand_f *);/* Set timeout handler */
 465
 466 /* Transmit "NetTxPacket" */
 467 extern void NetSendPacket(uchar *, int);
 468
 469 /*
 470  * Transmit UDP packet, performing ARP request if needed
 471  *
 472  * @param ether Raw packet buffer
 473  * @param dest IP address to send the datagram to
 474  * @param dport Destination UDP port
 475  * @param sport Source UDP port
 476  * @param payload_len Length of data after the UDP header
 477  */
 478 extern int      NetSendUDPPacket(uchar *ether, IPaddr_t dest, int dport,
 479                         int sport, int payload_len);
 480
 481 /* Processes a received packet */
 482 extern void NetReceive(uchar *, int);
 483
 484 #ifdef CONFIG_NETCONSOLE
 485 void NcStart(void);
 486 int nc_input_packet(uchar *pkt, unsigned dest, unsigned src, unsigned len);
 487 #endif
 488
 489 /*
 490  * Check if autoload is enabled. If so, use either NFS or TFTP to download
 491  * the boot file.
 492  */
 493 void net_auto_load(void);
 494
 495 /*
 496  * The following functions are a bit ugly, but necessary to deal with
 497  * alignment restrictions on ARM.
 498  *
 499  * We're using inline functions, which had the smallest memory
 500  * footprint in our tests.
 501  */
 502 /* return IP *in network byteorder* */
 503 static inline IPaddr_t NetReadIP(void *from)
 504 {
 505         IPaddr_t ip;
 506
 507         memcpy((void *)&ip, (void *)from, sizeof(ip));
 508         return ip;
 509 }
 510
 511 /* return ulong *in network byteorder* */
 512 static inline ulong NetReadLong(ulong *from)
 513 {
 514         ulong l;
 515
 516         memcpy((void *)&l, (void *)from, sizeof(l));
 517         return l;
 518 }
 519
 520 /* write IP *in network byteorder* */
 521 static inline void NetWriteIP(void *to, IPaddr_t ip)
 522 {
 523         memcpy(to, (void *)&ip, sizeof(ip));
 524 }
 525
 526 /* copy IP */
 527 static inline void NetCopyIP(void *to, void *from)
 528 {
 529         memcpy((void *)to, from, sizeof(IPaddr_t));
 530 }
 531
 532 /* copy ulong */
 533 static inline void NetCopyLong(ulong *to, ulong *from)
 534 {
 535         memcpy((void *)to, (void *)from, sizeof(ulong));
 536 }
 537
 538 /**
 539  * is_zero_ether_addr - Determine if give Ethernet address is all zeros.
 540  * @addr: Pointer to a six-byte array containing the Ethernet address
 541  *
 542  * Return true if the address is all zeroes.
 543  */
 544 static inline int is_zero_ether_addr(const u8 *addr)
 545 {
 546         return !(addr[0] | addr[1] | addr[2] | addr[3] | addr[4] | addr[5]);
 547 }
 548
 549 /**
 550  * is_multicast_ether_addr - Determine if the Ethernet address is a multicast.
 551  * @addr: Pointer to a six-byte array containing the Ethernet address
 552  *
 553  * Return true if the address is a multicast address.
 554  * By definition the broadcast address is also a multicast address.
 555  */
 556 static inline int is_multicast_ether_addr(const u8 *addr)
 557 {
 558         return 0x01 & addr[0];
 559 }
 560
 561 /*
 562  * is_broadcast_ether_addr - Determine if the Ethernet address is broadcast
 563  * @addr: Pointer to a six-byte array containing the Ethernet address
 564  *
 565  * Return true if the address is the broadcast address.
 566  */
 567 static inline int is_broadcast_ether_addr(const u8 *addr)
 568 {
 569         return (addr[0] & addr[1] & addr[2] & addr[3] & addr[4] & addr[5]) ==
 570                 0xff;
 571 }
 572
 573 /*
 574  * is_valid_ether_addr - Determine if the given Ethernet address is valid
 575  * @addr: Pointer to a six-byte array containing the Ethernet address
 576  *
 577  * Check that the Ethernet address (MAC) is not 00:00:00:00:00:00, is not
 578  * a multicast address, and is not FF:FF:FF:FF:FF:FF.
 579  *
 580  * Return true if the address is valid.
 581  */
 582 static inline int is_valid_ether_addr(const u8 *addr)
 583 {
 584         /* FF:FF:FF:FF:FF:FF is a multicast address so we don't need to
 585          * explicitly check for it here. */
 586         return !is_multicast_ether_addr(addr) && !is_zero_ether_addr(addr);
 587 }
 588
 589 /* Convert an IP address to a string */
 590 extern void ip_to_string(IPaddr_t x, char *s);
 591
 592 /* Convert a string to ip address */
 593 extern IPaddr_t string_to_ip(const char *s);
 594
 595 /* Convert a VLAN id to a string */
 596 extern void VLAN_to_string(ushort x, char *s);
 597
 598 /* Convert a string to a vlan id */
 599 extern ushort string_to_VLAN(const char *s);
 600
 601 /* read a VLAN id from an environment variable */
 602 extern ushort getenv_VLAN(char *);
 603
 604 /* copy a filename (allow for "..." notation, limit length) */
 605 extern void copy_filename(char *dst, const char *src, int size);
 606
 607 /* get a random source port */
 608 extern unsigned int random_port(void);
 609
 610 /**********************************************************************/
 611
 612 #endif /* __NET_H__ */