#include <u.h>#include <libc.h>#include <ctype.h>#include <ip.h> static char*v4parseip0(uchar *to, char *from, int *err){	int i;	ulong l;	char *p; 	p = from;	for(i = 0; i < 4 && *p; i++){		l = strtoul(p, &p, 0);		if(l > 255)			*err = 1;		to[i] = l;		if(*p == '.')			p++;	}	switch(CLASS(to)){	case 0:	/* class A - 1 uchar net */	case 1:		if(i == 3){			to[3] = to[2];			to[2] = to[1];			to[1] = 0;		} else if (i == 2){			to[3] = to[1];			to[1] = 0;		}		break;	case 2:	/* class B - 2 uchar net */		if(i == 3){			to[3] = to[2];			to[2] = 0;		}		break;	}	return p;} char*v4parseip(uchar *to, char *from){	int err; 	return v4parseip0(to, from, &err);} static intipcharok(int c){	return c == '.' || c == ':' || isascii(c) && isxdigit(c);} static intdelimchar(int c){	if(c == '\0')		return 1;	if(c == '.' || c == ':' || isascii(c) && isalnum(c))		return 0;	return 1;} /* * `from' may contain an address followed by other characters, * at least in /boot, so we permit whitespace (and more) after the address. * we do ensure that "delete" cannot be parsed as "de::". * * some callers don't check the return value for errors, so * set `to' to something distinctive in the case of a parse error. */vlongparseip(uchar *to, char *from){	int i, err, elipsis = 0, v4 = 1;	ulong x;	char *p, *op; 	memset(to, 0, IPaddrlen);	p = from;	err = 0;	for(i = 0; i < IPaddrlen && ipcharok(*p); i+=2){		op = p;		x = strtoul(p, &p, 16);		if(*p == '.' || (*p == 0 && i == 0)){	/* ends with v4? */			if(i + 4 > IPaddrlen){				memset(to, 0, IPaddrlen);				return -1;		/* parse error */			}			p = v4parseip0(to+i, op, &err);			i += 4;			break;		}		/* v6: at most 4 hex digits, followed by colon or delim */		if(x != (ushort)x || *p != ':' && !delimchar(*p)) {			memset(to, 0, IPaddrlen);			return -1;			/* parse error */		}		to[i] = x>>8;		to[i+1] = x;		if(*p == ':'){			v4 = 0;			if(*++p == ':'){	/* :: is elided zero short(s) */				if (elipsis) {					memset(to, 0, IPaddrlen);					return -1;	/* second :: */				}				elipsis = i+2;				p++;			}		} else if (p == op)		/* strtoul made no progress? */			break;	}	if (err || p == from || !delimchar(*p)) {		memset(to, 0, IPaddrlen);		return -1;				/* parse error */	}	if(i < IPaddrlen){		memmove(&to[elipsis+IPaddrlen-i], &to[elipsis], i-elipsis);		memset(&to[elipsis], 0, IPaddrlen-i);	}	if(v4){		to[10] = to[11] = 0xff;		return nhgetl(to + IPv4off);	} else		return 6;} /* *  hack to allow ip v4 masks to be entered in the old *  style */vlongparseipmask(uchar *to, char *from){	int i, w;	vlong x;	uchar *p; 	if(*from == '/'){		/* as a number of prefix bits */		i = atoi(from+1);		if(i < 0)			i = 0;		if(i > 128)			i = 128;		w = i;		memset(to, 0, IPaddrlen);		for(p = to; i >= 8; i -= 8)			*p++ = 0xff;		if(i > 0)			*p = ~((1<<(8-i))-1);		x = nhgetl(to+IPv4off);		/*		 * identify as ipv6 if the mask is inexpressible as a v4 mask		 * (because it has too few mask bits).  Arguably, we could		 * always return 6 here.		 */		if (w < 8*(IPaddrlen-IPv4addrlen))			return 6;	} else {		/* as a straight v4 bit mask */		x = parseip(to, from);		if (x != -1)			x = (ulong)nhgetl(to + IPv4off);		if(memcmp(to, v4prefix, IPv4off) == 0)			memset(to, 0xff, IPv4off);	}	return x;} /* *  parse a v4 ip address/mask in cidr format */char*v4parsecidr(uchar *addr, uchar *mask, char *from){	int i;	char *p;	uchar *a; 	p = v4parseip(addr, from); 	if(*p == '/'){		/* as a number of prefix bits */		i = strtoul(p+1, &p, 0);		if(i > 32)			i = 32;		memset(mask, 0, IPv4addrlen);		for(a = mask; i >= 8; i -= 8)			*a++ = 0xff;		if(i > 0)			*a = ~((1<<(8-i))-1);	} else 		memmove(mask, defmask(addr), IPv4addrlen);	return p;}