diff options
Diffstat (limited to 'lwip/src/core/ipv4/ip4_addr.c')
-rw-r--r-- | lwip/src/core/ipv4/ip4_addr.c | 321 |
1 files changed, 321 insertions, 0 deletions
diff --git a/lwip/src/core/ipv4/ip4_addr.c b/lwip/src/core/ipv4/ip4_addr.c new file mode 100644 index 0000000..33204d1 --- /dev/null +++ b/lwip/src/core/ipv4/ip4_addr.c @@ -0,0 +1,321 @@ +/** + * @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 <adam@sics.se> + * + */ + +#include "lwip/opt.h" + +#if LWIP_IPV4 + +#include "lwip/ip_addr.h" +#include "lwip/netif.h" + +/* used by IP4_ADDR_ANY and IP_ADDR_BROADCAST in ip_addr.h */ +const ip_addr_t ip_addr_any = IPADDR4_INIT(IPADDR_ANY); +const ip_addr_t ip_addr_broadcast = IPADDR4_INIT(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(u32_t addr, const struct netif *netif) +{ + ip4_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_ip4_addr(netif))) { + return 0; + /* on the same (sub) network... */ + } else if (ip4_addr_netcmp(&ipaddr, netif_ip4_addr(netif), netif_ip4_netmask(netif)) + /* ...and host identifier bits are all ones? =>... */ + && ((addr & ~ip4_addr_get_u32(netif_ip4_netmask(netif))) == + (IPADDR_BROADCAST & ~ip4_addr_get_u32(netif_ip4_netmask(netif))))) { + /* => 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 = 1UL << 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; +} + +/** + * Ascii internet address interpretation routine. + * The value returned is in network order. + * + * @param cp IP address in ascii representation (e.g. "127.0.0.1") + * @return ip address in network order + */ +u32_t +ipaddr_addr(const char *cp) +{ + ip4_addr_t val; + + if (ip4addr_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 representation (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 +ip4addr_aton(const char *cp, ip4_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 (!lwip_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 (lwip_isdigit(c)) { + val = (val * base) + (u32_t)(c - '0'); + c = *++cp; + } else if (base == 16 && lwip_isxdigit(c)) { + val = (val << 4) | (u32_t)(c + 10 - (lwip_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' && !lwip_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; + } + if (parts[0] > 0xff) { + return 0; + } + val |= parts[0] << 24; + break; + + case 3: /* a.b.c -- 8.8.16 bits */ + if (val > 0xffff) { + return 0; + } + if ((parts[0] > 0xff) || (parts[1] > 0xff)) { + 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; + } + if ((parts[0] > 0xff) || (parts[1] > 0xff) || (parts[2] > 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, lwip_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 + * representation of addr + */ +char * +ip4addr_ntoa(const ip4_addr_t *addr) +{ + static char str[IP4ADDR_STRLEN_MAX]; + return ip4addr_ntoa_r(addr, str, IP4ADDR_STRLEN_MAX); +} + +/** + * Same as ip4addr_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 * +ip4addr_ntoa_r(const ip4_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++] = (char)('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; +} + +#endif /* LWIP_IPV4 */ |