/** * @file * This is the IPv4 address tools implementation. * */ /* * Copyright (c) 2001-2004 Swedish Institute of Computer Science. * All rights reserved. * * Redistribution and use in source and binary forms, with or without modification, * are permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * 3. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY * OF SUCH DAMAGE. * * This file is part of the lwIP TCP/IP stack. * * Author: Adam Dunkels * */ #include "lwip/opt.h" #include "lwip/ip_addr.h" #include "lwip/netif.h" /* used by IP_ADDR_ANY and IP_ADDR_BROADCAST in ip_addr.h */ const ip_addr_t ip_addr_any = { IPADDR_ANY }; const ip_addr_t ip_addr_broadcast = { IPADDR_BROADCAST }; /** * Determine if an address is a broadcast address on a network interface * * @param addr address to be checked * @param netif the network interface against which the address is checked * @return returns non-zero if the address is a broadcast address */ u8_t ip4_addr_isbroadcast(u32_t addr, const struct netif *netif) { ip_addr_t ipaddr; ip4_addr_set_u32(&ipaddr, addr); /* all ones (broadcast) or all zeroes (old skool broadcast) */ if ((~addr == IPADDR_ANY) || (addr == IPADDR_ANY)) { return 1; /* no broadcast support on this network interface? */ } else if ((netif->flags & NETIF_FLAG_BROADCAST) == 0) { /* the given address cannot be a broadcast address * nor can we check against any broadcast addresses */ return 0; /* address matches network interface address exactly? => no broadcast */ } else if (addr == ip4_addr_get_u32(&netif->ip_addr)) { return 0; /* on the same (sub) network... */ } else if (ip_addr_netcmp(&ipaddr, &(netif->ip_addr), &(netif->netmask)) /* ...and host identifier bits are all ones? =>... */ && ((addr & ~ip4_addr_get_u32(&netif->netmask)) == (IPADDR_BROADCAST & ~ip4_addr_get_u32(&netif->netmask)))) { /* => network broadcast address */ return 1; } else { return 0; } } /** Checks if a netmask is valid (starting with ones, then only zeros) * * @param netmask the IPv4 netmask to check (in network byte order!) * @return 1 if the netmask is valid, 0 if it is not */ u8_t ip4_addr_netmask_valid(u32_t netmask) { u32_t mask; u32_t nm_hostorder = lwip_htonl(netmask); /* first, check for the first zero */ for (mask = 1U << 31 ; mask != 0; mask >>= 1) { if ((nm_hostorder & mask) == 0) { break; } } /* then check that there is no one */ for (; mask != 0; mask >>= 1) { if ((nm_hostorder & mask) != 0) { /* there is a one after the first zero -> invalid */ return 0; } } /* no one after the first zero -> valid */ return 1; } /* Here for now until needed in other places in lwIP */ #ifndef isprint #define in_range(c, lo, up) ((u8_t)c >= lo && (u8_t)c <= up) #define isprint(c) in_range(c, 0x20, 0x7f) #define isdigit(c) in_range(c, '0', '9') #define isxdigit(c) (isdigit(c) || in_range(c, 'a', 'f') || in_range(c, 'A', 'F')) #define islower(c) in_range(c, 'a', 'z') #define isspace(c) (c == ' ' || c == '\f' || c == '\n' || c == '\r' || c == '\t' || c == '\v') #endif /** * Ascii internet address interpretation routine. * The value returned is in network order. * * @param cp IP address in ascii represenation (e.g. "127.0.0.1") * @return ip address in network order */ u32_t ipaddr_addr(const char *cp) { ip_addr_t val; if (ipaddr_aton(cp, &val)) { return ip4_addr_get_u32(&val); } return (IPADDR_NONE); } /** * Check whether "cp" is a valid ascii representation * of an Internet address and convert to a binary address. * Returns 1 if the address is valid, 0 if not. * This replaces inet_addr, the return value from which * cannot distinguish between failure and a local broadcast address. * * @param cp IP address in ascii represenation (e.g. "127.0.0.1") * @param addr pointer to which to save the ip address in network order * @return 1 if cp could be converted to addr, 0 on failure */ int ipaddr_aton(const char *cp, ip_addr_t *addr) { u32_t val; u8_t base; char c; u32_t parts[4]; u32_t *pp = parts; c = *cp; for (;;) { /* * Collect number up to ``.''. * Values are specified as for C: * 0x=hex, 0=octal, 1-9=decimal. */ if (!isdigit(c)) return (0); val = 0; base = 10; if (c == '0') { c = *++cp; if (c == 'x' || c == 'X') { base = 16; c = *++cp; } else base = 8; } for (;;) { if (isdigit(c)) { val = (val * base) + (int)(c - '0'); c = *++cp; } else if (base == 16 && isxdigit(c)) { val = (val << 4) | (int)(c + 10 - (islower(c) ? 'a' : 'A')); c = *++cp; } else break; } if (c == '.') { /* * Internet format: * a.b.c.d * a.b.c (with c treated as 16 bits) * a.b (with b treated as 24 bits) */ if (pp >= parts + 3) { return (0); } *pp++ = val; c = *++cp; } else break; } /* * Check for trailing characters. */ if (c != '\0' && !isspace(c)) { return (0); } /* * Concoct the address according to * the number of parts specified. */ switch (pp - parts + 1) { case 0: return (0); /* initial nondigit */ case 1: /* a -- 32 bits */ break; case 2: /* a.b -- 8.24 bits */ if (val > 0xffffffUL) { return (0); } val |= parts[0] << 24; break; case 3: /* a.b.c -- 8.8.16 bits */ if (val > 0xffff) { return (0); } val |= (parts[0] << 24) | (parts[1] << 16); break; case 4: /* a.b.c.d -- 8.8.8.8 bits */ if (val > 0xff) { return (0); } val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8); break; default: LWIP_ASSERT("unhandled", 0); break; } if (addr) { ip4_addr_set_u32(addr, htonl(val)); } return (1); } /** * Convert numeric IP address into decimal dotted ASCII representation. * returns ptr to static buffer; not reentrant! * * @param addr ip address in network order to convert * @return pointer to a global static (!) buffer that holds the ASCII * represenation of addr */ char * ipaddr_ntoa(const ip_addr_t *addr) { static char str[16]; return ipaddr_ntoa_r(addr, str, 16); } /** * Same as ipaddr_ntoa, but reentrant since a user-supplied buffer is used. * * @param addr ip address in network order to convert * @param buf target buffer where the string is stored * @param buflen length of buf * @return either pointer to buf which now holds the ASCII * representation of addr or NULL if buf was too small */ char *ipaddr_ntoa_r(const ip_addr_t *addr, char *buf, int buflen) { u32_t s_addr; char inv[3]; char *rp; u8_t *ap; u8_t rem; u8_t n; u8_t i; int len = 0; s_addr = ip4_addr_get_u32(addr); rp = buf; ap = (u8_t *)&s_addr; for(n = 0; n < 4; n++) { i = 0; do { rem = *ap % (u8_t)10; *ap /= (u8_t)10; inv[i++] = '0' + rem; } while(*ap); while(i--) { if (len++ >= buflen) { return NULL; } *rp++ = inv[i]; } if (len++ >= buflen) { return NULL; } *rp++ = '.'; ap++; } *--rp = 0; return buf; }