/* | |
* 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> | |
* | |
*/ | |
/* inet.c | |
* | |
* Functions common to all TCP/IP modules, such as the Internet checksum and the | |
* byte order functions. | |
* | |
*/ | |
#include "lwip/opt.h" | |
#include "lwip/arch.h" | |
#include "lwip/def.h" | |
#include "lwip/inet.h" | |
#include "lwip/sys.h" | |
/* These are some reference implementations of the checksum algorithm, with the | |
* aim of being simple, correct and fully portable. Checksumming is the | |
* first thing you would want to optimize for your platform. If you create | |
* your own version, link it in and in your sys_arch.h put: | |
* | |
* #define LWIP_CHKSUM <your_checksum_routine> | |
*/ | |
#ifndef LWIP_CHKSUM | |
#define LWIP_CHKSUM lwip_standard_chksum | |
#if 1 /* Version A */ | |
/** | |
* lwip checksum | |
* | |
* @param dataptr points to start of data to be summed at any boundary | |
* @param len length of data to be summed | |
* @return host order (!) lwip checksum (non-inverted Internet sum) | |
* | |
* @note accumulator size limits summable length to 64k | |
* @note host endianess is irrelevant (p3 RFC1071) | |
*/ | |
static u16_t | |
lwip_standard_chksum(void *dataptr, u16_t len) | |
{ | |
u32_t acc; | |
u16_t src; | |
u8_t *octetptr; | |
acc = 0; | |
/* dataptr may be at odd or even addresses */ | |
octetptr = (u8_t*)dataptr; | |
while (len > 1) | |
{ | |
/* declare first octet as most significant | |
thus assume network order, ignoring host order */ | |
src = (*octetptr) << 8; | |
octetptr++; | |
/* declare second octet as least significant */ | |
src |= (*octetptr); | |
octetptr++; | |
acc += src; | |
len -= 2; | |
} | |
if (len > 0) | |
{ | |
/* accumulate remaining octet */ | |
src = (*octetptr) << 8; | |
acc += src; | |
} | |
/* add deferred carry bits */ | |
acc = (acc >> 16) + (acc & 0x0000ffffUL); | |
if ((acc & 0xffff0000) != 0) { | |
acc = (acc >> 16) + (acc & 0x0000ffffUL); | |
} | |
/* This maybe a little confusing: reorder sum using htons() | |
instead of ntohs() since it has a little less call overhead. | |
The caller must invert bits for Internet sum ! */ | |
return htons((u16_t)acc); | |
} | |
#endif | |
#if 0 /* Version B */ | |
/* | |
* Curt McDowell | |
* Broadcom Corp. | |
* csm@broadcom.com | |
* | |
* IP checksum two bytes at a time with support for | |
* unaligned buffer. | |
* Works for len up to and including 0x20000. | |
* by Curt McDowell, Broadcom Corp. 12/08/2005 | |
*/ | |
static u16_t | |
lwip_standard_chksum(void *dataptr, int len) | |
{ | |
u8_t *pb = dataptr; | |
u16_t *ps, t = 0; | |
u32_t sum = 0; | |
int odd = ((u32_t)pb & 1); | |
/* Get aligned to u16_t */ | |
if (odd && len > 0) { | |
((u8_t *)&t)[1] = *pb++; | |
len--; | |
} | |
/* Add the bulk of the data */ | |
ps = (u16_t *)pb; | |
while (len > 1) { | |
sum += *ps++; | |
len -= 2; | |
} | |
/* Consume left-over byte, if any */ | |
if (len > 0) | |
((u8_t *)&t)[0] = *(u8_t *)ps;; | |
/* Add end bytes */ | |
sum += t; | |
/* Fold 32-bit sum to 16 bits */ | |
while (sum >> 16) | |
sum = (sum & 0xffff) + (sum >> 16); | |
/* Swap if alignment was odd */ | |
if (odd) | |
sum = ((sum & 0xff) << 8) | ((sum & 0xff00) >> 8); | |
return sum; | |
} | |
#endif | |
#if 0 /* Version C */ | |
/** | |
* An optimized checksum routine. Basically, it uses loop-unrolling on | |
* the checksum loop, treating the head and tail bytes specially, whereas | |
* the inner loop acts on 8 bytes at a time. | |
* | |
* @arg start of buffer to be checksummed. May be an odd byte address. | |
* @len number of bytes in the buffer to be checksummed. | |
* | |
* by Curt McDowell, Broadcom Corp. December 8th, 2005 | |
*/ | |
static u16_t | |
lwip_standard_chksum(void *dataptr, int len) | |
{ | |
u8_t *pb = dataptr; | |
u16_t *ps, t = 0; | |
u32_t *pl; | |
u32_t sum = 0, tmp; | |
/* starts at odd byte address? */ | |
int odd = ((u32_t)pb & 1); | |
if (odd && len > 0) { | |
((u8_t *)&t)[1] = *pb++; | |
len--; | |
} | |
ps = (u16_t *)pb; | |
if (((u32_t)ps & 3) && len > 1) { | |
sum += *ps++; | |
len -= 2; | |
} | |
pl = (u32_t *)ps; | |
while (len > 7) { | |
tmp = sum + *pl++; /* ping */ | |
if (tmp < sum) | |
tmp++; /* add back carry */ | |
sum = tmp + *pl++; /* pong */ | |
if (sum < tmp) | |
sum++; /* add back carry */ | |
len -= 8; | |
} | |
/* make room in upper bits */ | |
sum = (sum >> 16) + (sum & 0xffff); | |
ps = (u16_t *)pl; | |
/* 16-bit aligned word remaining? */ | |
while (len > 1) { | |
sum += *ps++; | |
len -= 2; | |
} | |
/* dangling tail byte remaining? */ | |
if (len > 0) /* include odd byte */ | |
((u8_t *)&t)[0] = *(u8_t *)ps; | |
sum += t; /* add end bytes */ | |
while (sum >> 16) /* combine halves */ | |
sum = (sum >> 16) + (sum & 0xffff); | |
if (odd) | |
sum = ((sum & 0xff) << 8) | ((sum & 0xff00) >> 8); | |
return sum; | |
} | |
#endif | |
#endif /* LWIP_CHKSUM */ | |
/* inet_chksum_pseudo: | |
* | |
* Calculates the pseudo Internet checksum used by TCP and UDP for a pbuf chain. | |
*/ | |
u16_t | |
inet_chksum_pseudo(struct pbuf *p, | |
struct ip_addr *src, struct ip_addr *dest, | |
u8_t proto, u16_t proto_len) | |
{ | |
u32_t acc; | |
struct pbuf *q; | |
u8_t swapped; | |
acc = 0; | |
swapped = 0; | |
/* iterate through all pbuf in chain */ | |
for(q = p; q != NULL; q = q->next) { | |
LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): checksumming pbuf %p (has next %p) \n", | |
(void *)q, (void *)q->next)); | |
acc += LWIP_CHKSUM(q->payload, q->len); | |
/*LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): unwrapped lwip_chksum()=%"X32_F" \n", acc));*/ | |
while (acc >> 16) { | |
acc = (acc & 0xffffUL) + (acc >> 16); | |
} | |
if (q->len % 2 != 0) { | |
swapped = 1 - swapped; | |
acc = ((acc & 0xff) << 8) | ((acc & 0xff00UL) >> 8); | |
} | |
/*LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): wrapped lwip_chksum()=%"X32_F" \n", acc));*/ | |
} | |
if (swapped) { | |
acc = ((acc & 0xff) << 8) | ((acc & 0xff00UL) >> 8); | |
} | |
acc += (src->addr & 0xffffUL); | |
acc += ((src->addr >> 16) & 0xffffUL); | |
acc += (dest->addr & 0xffffUL); | |
acc += ((dest->addr >> 16) & 0xffffUL); | |
acc += (u32_t)htons((u16_t)proto); | |
acc += (u32_t)htons(proto_len); | |
while (acc >> 16) { | |
acc = (acc & 0xffffUL) + (acc >> 16); | |
} | |
LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): pbuf chain lwip_chksum()=%"X32_F"\n", acc)); | |
return (u16_t)~(acc & 0xffffUL); | |
} | |
/* inet_chksum: | |
* | |
* Calculates the Internet checksum over a portion of memory. Used primarily for IP | |
* and ICMP. | |
*/ | |
u16_t | |
inet_chksum(void *dataptr, u16_t len) | |
{ | |
u32_t acc; | |
acc = LWIP_CHKSUM(dataptr, len); | |
while (acc >> 16) { | |
acc = (acc & 0xffff) + (acc >> 16); | |
} | |
return (u16_t)~(acc & 0xffff); | |
} | |
u16_t | |
inet_chksum_pbuf(struct pbuf *p) | |
{ | |
u32_t acc; | |
struct pbuf *q; | |
u8_t swapped; | |
acc = 0; | |
swapped = 0; | |
for(q = p; q != NULL; q = q->next) { | |
acc += LWIP_CHKSUM(q->payload, q->len); | |
while (acc >> 16) { | |
acc = (acc & 0xffffUL) + (acc >> 16); | |
} | |
if (q->len % 2 != 0) { | |
swapped = 1 - swapped; | |
acc = (acc & 0x00ffUL << 8) | (acc & 0xff00UL >> 8); | |
} | |
} | |
if (swapped) { | |
acc = ((acc & 0x00ffUL) << 8) | ((acc & 0xff00UL) >> 8); | |
} | |
return (u16_t)~(acc & 0xffffUL); | |
} | |
/* 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. | |
*/ | |
u32_t | |
inet_addr(const char *cp) | |
{ | |
struct in_addr val; | |
if (inet_aton(cp, &val)) { | |
return (val.s_addr); | |
} | |
return (INADDR_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. | |
*/ | |
int | |
inet_aton(const char *cp, struct in_addr *addr) | |
{ | |
u32_t val; | |
int base, n, 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' && (!isprint(c) || !isspace(c))) | |
return (0); | |
/* | |
* Concoct the address according to | |
* the number of parts specified. | |
*/ | |
n = pp - parts + 1; | |
switch (n) { | |
case 0: | |
return (0); /* initial nondigit */ | |
case 1: /* a -- 32 bits */ | |
break; | |
case 2: /* a.b -- 8.24 bits */ | |
if (val > 0xffffff) | |
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; | |
} | |
if (addr) | |
addr->s_addr = htonl(val); | |
return (1); | |
} | |
/* Convert numeric IP address into decimal dotted ASCII representation. | |
* returns ptr to static buffer; not reentrant! | |
*/ | |
char * | |
inet_ntoa(struct in_addr addr) | |
{ | |
static char str[16]; | |
u32_t s_addr = addr.s_addr; | |
char inv[3]; | |
char *rp; | |
u8_t *ap; | |
u8_t rem; | |
u8_t n; | |
u8_t i; | |
rp = str; | |
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--) | |
*rp++ = inv[i]; | |
*rp++ = '.'; | |
ap++; | |
} | |
*--rp = 0; | |
return str; | |
} | |
/* | |
* These are reference implementations of the byte swapping functions. | |
* Again with the aim of being simple, correct and fully portable. | |
* Byte swapping is the second thing you would want to optimize. You will | |
* need to port it to your architecture and in your cc.h: | |
* | |
* #define LWIP_PLATFORM_BYTESWAP 1 | |
* #define LWIP_PLATFORM_HTONS(x) <your_htons> | |
* #define LWIP_PLATFORM_HTONL(x) <your_htonl> | |
* | |
* Note ntohs() and ntohl() are merely references to the htonx counterparts. | |
*/ | |
#ifndef BYTE_ORDER | |
#error BYTE_ORDER is not defined | |
#endif | |
#if (LWIP_PLATFORM_BYTESWAP == 0) && (BYTE_ORDER == LITTLE_ENDIAN) | |
u16_t | |
htons(u16_t n) | |
{ | |
return ((n & 0xff) << 8) | ((n & 0xff00) >> 8); | |
} | |
u16_t | |
ntohs(u16_t n) | |
{ | |
return htons(n); | |
} | |
u32_t | |
htonl(u32_t n) | |
{ | |
return ((n & 0xff) << 24) | | |
((n & 0xff00) << 8) | | |
((n & 0xff0000) >> 8) | | |
((n & 0xff000000) >> 24); | |
} | |
u32_t | |
ntohl(u32_t n) | |
{ | |
return htonl(n); | |
} | |
#endif /* (LWIP_PLATFORM_BYTESWAP == 0) && (BYTE_ORDER == LITTLE_ENDIAN) */ |