1991/0401/port/deviproute.c (diff list | history)

1991/0331/sys/src/9/port/deviproute.c:4,12 – 1991/0401/sys/src/9/port/deviproute.c:4,20 (short | long | prev | next)
1991/0331		#include "dat.h" #include "fns.h" #include "errno.h"
1991/0401		#include "arp.h" #include "ipdat.h"
1991/0330
1991/0331		#include "devtab.h"
1991/0401		/* * All ip numbers and masks are stored as ulongs. * All interfaces to this code uses the standard byte * string representation. */
1991/0330		typedef struct Iproute Iproute; typedef struct Iprtab Iprtab;
1991/0331/sys/src/9/port/deviproute.c:16,41 – 1991/0401/sys/src/9/port/deviproute.c:24,35
1991/0330		}; /* * Standard ip masks for the 3 classes */ uchar classmask[4][4] = { 0xff, 0, 0, 0, 0xff, 0, 0, 0, 0xff, 0xff, 0, 0, 0xff, 0xff, 0xff, 0, }; #define CLASSMASK(x) classmask[(*x>>6) & 3]
1991/0331		uchar netbytes[4] = { 1, 1, 2, 3 }; #define NETBYTES(x) netbytes[(*x>>6) & 3]
1991/0330		/* * routes */ struct Iproute { uchar dst[4]; uchar gate[4]; uchar mask[4];
1991/0401		ulong dst; ulong gate; ulong mask;
1991/0330		Iproute *next; int inuse; };
1991/0331/sys/src/9/port/deviproute.c:48,130 – 1991/0401/sys/src/9/port/deviproute.c:42,85
1991/0330		Iprtab iprtab;
1991/0331		/* * Convert string to ip address. This is rediculously difficult because * the designers of ip decided to allow any leading zero bytes in the * host part to be left out. */
1991/0330		void
1991/0331		strtoip(char *s, uchar *addr)
1991/0330		{
1991/0331		int i, off, first; char *rptr = s;
1991/0330
1991/0331		/* convert the bytes */ for(i = 0; i<4 & *rptr; i++) addr[i] = strtoul(rptr, &rptr, 0);                  /* move host bytes to the right place */ first = NETBYTES(addr); off = 4 - i; if(off) while(i != first){ --i; addr[i+off] = addr[i]; }
1991/0330		}                  /* * The chosen route is the one obeys the constraint * r->mask[x] & dst[x] == r->dst[x] for x in 0 1 2 3
1991/0401		* r->mask & dst == r->dst
1991/0330		* * If there are several matches, the one whose mask has the most * leading ones (and hence is the most specific) wins. * * If there is no match, the default gateway is chosen.
1991/0401		* leading ones (and hence is the most specific) wins. This is * forced by storing the routes in decreasing number of ones order * and returning the first match. The default gateway has no ones * in the mask and is thus the last matched.
1991/0330		*/ void iproute(uchar *dst, uchar *gate) { Iproute *r;
1991/0401		ulong udst;
1991/0330
1991/0401		udst = nhgetl(dst); if((udst&Mymask) == (Myip&Mymask)){ memmove(gate, dst, 4); return; }
1991/0330		/* * first check routes */ lock(&iprtab); for(r = iprtab.first; r; r = r->next){ if((r->mask[0]&dst[0]) == r->dst[0] && (r->mask[1]&dst[1]) == r->dst[1] && (r->mask[2]&dst[2]) == r->dst[2] && (r->mask[3]&dst[3]) == r->dst[3]){ memmove(gate, r->gate, 4); unlock(&iprtab);
1991/0401		if((r->mask&udst) == r->dst){ hnputl(gate, r->gate);
1991/0330		return; } } unlock(&iprtab); /* * else just return what we got
1991/0401		* else just return the same address
1991/0330		*/ memmove(gate, dst, 4); } /* * Compares 2 subnet masks and returns an integer less than, equal to, * or greater than 0, according as m1 is numericly less than, * equal to, or greater than m2. */ ipmaskcmp(uchar *m1, uchar *m2) { int a, i;                  for(i = 0; i < 4; i++){ if(a = *m1++ - *m2++) return a; } return 0; }                  /* * Add a route, create a mask if the first mask is 0. * * All routes are stored sorted by the length of leading
1991/0331/sys/src/9/port/deviproute.c:133,152 – 1991/0401/sys/src/9/port/deviproute.c:88,103
1991/0330		* NOTE: A default route has an all zeroes mask and dst. */ void ipaddroute(uchar *dst, uchar *mask, uchar *gate)
1991/0401		ipaddroute(ulong dst, ulong mask, ulong gate)
1991/0330		{ Iproute *r, *e, *free; int i; if(mask==0) mask = CLASSMASK(dst);                  /* * filter out impossible requests */ for(i = 0; i < 4; i++) if((dst[i]&mask[i]) != dst[i])
1991/0331		errors("bad ip route");
1991/0401		if((dst&mask) != dst) errors("bad ip route");
1991/0330		/* * see if we already have a route for
1991/0331/sys/src/9/port/deviproute.c:159,182 – 1991/0401/sys/src/9/port/deviproute.c:110,135
1991/0330		free = r; continue; } if(memcmp(dst, r->dst, 4)==0 && memcmp(mask, r->mask, 4)==0){ memmove(r->gate, gate, 4);
1991/0401		if(dst==r->dst && mask==r->mask){ r->gate = gate;
1991/0330		unlock(&iprtab); return; } }
1991/0331		if(free == 0)
1991/0401		if(free == 0){ unlock(&iprtab);
1991/0331		errors("no free ip routes");
1991/0401		}
1991/0330		/* * add the new route in sorted order */ memmove(free->dst, dst, 4); memmove(free->mask, mask, 4); memmove(free->gate, gate, 4);
1991/0401		free->dst = dst; free->mask = mask; free->gate = gate;
1991/0330		free->inuse = 1; for(r = iprtab.first; r; r = r->next){ if(ipmaskcmp(free->mask, r->mask) > 0)
1991/0401		for(r = e = iprtab.first; r; r = r->next){ if(mask > r->mask)
1991/0330		break; e = r; }
1991/0331/sys/src/9/port/deviproute.c:193,205 – 1991/0401/sys/src/9/port/deviproute.c:146,158
1991/0330		* remove a route */ void ipremroute(uchar *dst, uchar *mask)
1991/0401		ipremroute(ulong dst, ulong mask)
1991/0330		{ Iproute *r, *e; lock(&iprtab); for(r = iprtab.first; r; r = r->next){ if(memcmp(dst, r->dst, 4)==0 && memcmp(mask, r->mask, 4)==0){
1991/0401		for(r = e = iprtab.first; r; r = r->next){ if(dst==r->dst && mask==r->mask){
1991/0330		if(r == iprtab.first) iprtab.first = r->next; else
1991/0331/sys/src/9/port/deviproute.c:317,325 – 1991/0401/sys/src/9/port/deviproute.c:270,279
1991/0331		long iprouteread(Chan *c, void *a, long n) { char buf[IPR_ENTRYLEN*2];
1991/0401		char buf[IPR_ENTRYLEN*3];
1991/0331		Iproute *r; int part, bytes, size;
1991/0401		uchar dst[4], mask[4], gate[4];
1991/0331		switch((int)(c->qid.path&~CHDIR)){ case Qdir:
1991/0331/sys/src/9/port/deviproute.c:328,353 – 1991/0401/sys/src/9/port/deviproute.c:282,312
1991/0331		lock(&iprtab); part = c->offset/IPR_ENTRYLEN; for(r = iprtab.first; part && r; r = r->next) ;
1991/0401		part--;
1991/0331		bytes = c->offset; while(bytes < iprtab.n*IPR_ENTRYLEN && n){
1991/0401		while(r && bytes < iprtab.n*IPR_ENTRYLEN && n){
1991/0331		part = bytes%IPR_ENTRYLEN;
1991/0401		hnputl(dst, r->dst); hnputl(mask, r->mask); hnputl(gate, r->gate);
1991/0331		sprint(buf,"%d.%d.%d.%d & %d.%d.%d.%d -> %d.%d.%d.%d%s", r->dst[0], r->dst[1], r->dst[2], r->dst[3], r->mask[0], r->mask[1], r->mask[2], r->mask[3], r->gate[0], r->gate[1], r->gate[2], r->gate[3],
1991/0401		dst[0], dst[1], dst[2], dst[3], mask[0], mask[1], mask[2], mask[3], gate[0], gate[1], gate[2], gate[3],
1991/0331		PAD); buf[IPR_ENTRYLEN-1] = '\n'; size = IPR_ENTRYLEN - part; size = MIN(n, size);
1991/0401		if(size > n) size = n;
1991/0331		memmove(a, buf+part, size); a = (void *)((int)a + size); n -= size; bytes += size;
1991/0401		r = r->next;
1991/0331		} unlock(&iprtab); return bytes - c->offset;
1991/0331/sys/src/9/port/deviproute.c:364,370 – 1991/0401/sys/src/9/port/deviproute.c:323,329
1991/0331		{ char buf[IPR_ENTRYLEN]; char *field[4]; uchar mask[4], dst[4], gate[4];
1991/0401		Ipaddr mask, dst, gate;
1991/0331		int m; switch((int)(c->qid.path&~CHDIR)){
1991/0331/sys/src/9/port/deviproute.c:377,391 – 1991/0401/sys/src/9/port/deviproute.c:336,350
1991/0331		else if(strcmp(field[0], "add") == 0){ switch(m){ case 4: strtoip(field[1], dst); strtoip(field[2], mask); strtoip(field[3], gate);
1991/0401		dst = ipparse(field[1]); mask = ipparse(field[2]); gate = ipparse(field[3]);
1991/0331		ipaddroute(dst, mask, gate); break; case 3: strtoip(field[1], dst); strtoip(field[2], gate); ipaddroute(dst, 0, gate);
1991/0401		dst = ipparse(field[1]); gate = ipparse(field[2]); ipaddroute(dst, classmask[dst>>30], gate);
1991/0331		break; default: error(Ebadarg);
1991/0331/sys/src/9/port/deviproute.c:393,405 – 1991/0401/sys/src/9/port/deviproute.c:352,364
1991/0331		} else if(strcmp(field[0], "delete") == 0){ switch(m){ case 3: strtoip(field[1], dst); strtoip(field[2], mask);
1991/0401		dst = ipparse(field[1]); mask = ipparse(field[2]);
1991/0331		ipremroute(dst, mask); break; case 2: strtoip(field[1], dst); ipremroute(dst, 0);
1991/0401		dst = ipparse(field[1]); ipremroute(dst, classmask[dst>>30]);
1991/0331		break; default: error(Ebadarg);