ref: 7113f730dec2aba58935fdf0eb2b13ad58e63a69
parent: 16c87febd3875c4b0c9648c681735be3de8358bd
author: cinap_lenrek <[email protected]>
date: Fri Jun 1 19:53:09 EDT 2018
ndb/cs: make ipv6 only host practical by checking ip version on local interfaces avoid returning ip addresses that cannot be reached due to lack of a compatible ip address. this means when here is no ipv4 address configured, we wont return ipv4 addresses and would not query dns for an A record. likewise, when here is no ipv6 address configured then we wont query dns for an AAAA record. ipv6 lookups can still be disabled with the -4 flag just as before.
--- a/sys/src/cmd/ndb/cs.c
+++ b/sys/src/cmd/ndb/cs.c
@@ -80,7 +80,7 @@
Mlist *mlist;
int mfd[2];
int debug;
-int ipv6lookups = 1;
+
jmp_buf masterjmp; /* return through here after a slave process has been created */
int *isslave; /* *isslave non-zero means this is a slave process */
long active; /* number of active slaves */
@@ -136,7 +136,9 @@
char* iptrans(Ndbtuple*, Network*, char*, char*, int);
Ndbtuple* telcolookup(Network*, char*, char*);
char* telcotrans(Ndbtuple*, Network*, char*, char*, int);
+
Ndbtuple* dnsiplookup(char*, Ndbs*, int);
+Ndbtuple* myipinfo(Ndb *db, char **list, int n);
struct Network
{@@ -145,9 +147,8 @@
char *(*trans)(Ndbtuple*, Network*, char*, char*, int);
char considered; /* flag: ignored for "net!"? */
- char fasttimeouthack; /* flag. was for IL */
- char v4only;
- char v6only;
+ char fasttimeout; /* flag. was for IL */
+ char ipvers; /* flag: V4, V6 */
Network *next;
};
@@ -154,6 +155,9 @@
enum {Ntcp = 1,
+
+ V4 = 1,
+ V6 = 2,
};
/*
@@ -160,21 +164,22 @@
* net doesn't apply to (r)udp, icmp(v6), or telco (for speed).
*/
Network network[] = {- { "il", iplookup, iptrans, 0, 1, 1, 0, },- { "tcp", iplookup, iptrans, 0, 0, 0, 0, },- { "il", iplookup, iptrans, 0, 0, 1, 0, },- { "udp", iplookup, iptrans, 1, 0, 0, 0, },- { "icmp", iplookup, iptrans, 1, 0, 1, 0, },- { "icmpv6", iplookup, iptrans, 1, 0, 0, 1, },- { "rudp", iplookup, iptrans, 1, 0, 1, 0, },- { "ssh", iplookup, iptrans, 1, 0, 0, 0, },- { "telco", telcolookup, telcotrans, 1, 0, 0, 0, },+ { "il", iplookup, iptrans, 0, 1, V4, },+ { "tcp", iplookup, iptrans, 0, 0, V4|V6, },+ { "il", iplookup, iptrans, 0, 0, V4, },+ { "udp", iplookup, iptrans, 1, 0, V4|V6, },+ { "icmp", iplookup, iptrans, 1, 0, V4, },+ { "icmpv6", iplookup, iptrans, 1, 0, V6, },+ { "rudp", iplookup, iptrans, 1, 0, V4, },+ { "ssh", iplookup, iptrans, 1, 0, V4|V6, },+ { "telco", telcolookup, telcotrans, 1, 0, 0, }, { 0 },};
QLock ipifclock;
Ipifc *ipifcs;
-static Ndbtuple* myipinfo(Ndb *db, char **list, int n);
+int confipvers;
+int lookipvers = V4|V6;
char *mysysname;
@@ -231,7 +236,7 @@
ext[0] = 0;
ARGBEGIN{case '4':
- ipv6lookups = 0;
+ lookipvers = V4;
break;
case 'd':
debug = 1;
@@ -798,8 +803,8 @@
* toggle ipv6 lookups
*/
if(strncmp(job->request.data, "ipv6", 4)==0){- ipv6lookups ^= 1;
- syslog(1, logfile, "ipv6lookups %d", ipv6lookups);
+ lookipvers ^= V6;
+ syslog(1, logfile, "ipv6lookups %d", (lookipvers & V6) != 0);
goto send;
}
@@ -967,18 +972,26 @@
_exits(0);
}
-static int
-isvalidip(uchar *ip)
-{- return ipcmp(ip, IPnoaddr) != 0 && ipcmp(ip, v4prefix) != 0;
-}
-
void
readipinterfaces(void)
{+ Ipifc *ifc;
+ Iplifc *lifc;
+ int v;
+
+ v = 0;
qlock(&ipifclock);
ipifcs = readipifc(mntpt, ipifcs, -1);
+ for(ifc = ipifcs; ifc != nil; ifc = ifc->next){+ for(lifc = ifc->lifc; lifc != nil; lifc = lifc->next){+ if(isv4(lifc->ip))
+ v |= V4;
+ else
+ v |= V6;
+ }
+ }
qunlock(&ipifclock);
+ confipvers = v;
}
/*
@@ -1165,8 +1178,7 @@
char *cp;
Ndbtuple *nt, *t;
char reply[Maxreply];
- int i, rv;
- int hack;
+ int i, rv, fasttimeout;
/* open up the standard db files */
if(db == nil)
@@ -1186,9 +1198,9 @@
nt = (*np->lookup)(np, mf->host, mf->serv);
if(nt == nil)
continue;
- hack = np->fasttimeouthack && !lookforproto(nt, np->net);
+ fasttimeout = np->fasttimeout && !lookforproto(nt, np->net);
for(t = nt; mf->nreply < Nreply && t != nil; t = t->entry){- cp = (*np->trans)(t, np, mf->serv, mf->rem, hack);
+ cp = (*np->trans)(t, np, mf->serv, mf->rem, fasttimeout);
if(cp != nil){/* avoid duplicates */
for(i = 0; i < mf->nreply; i++)
@@ -1219,7 +1231,7 @@
* look for a specific network
*/
for(np = network; np->net != nil; np++){- if(np->fasttimeouthack)
+ if(np->fasttimeout)
continue;
if(strcmp(np->net, mf->net) == 0)
break;
@@ -1315,7 +1327,7 @@
return buf;
}
-static Ndbtuple*
+Ndbtuple*
myipinfo(Ndb *db, char **list, int n)
{Ndbtuple *t, *nt;
@@ -1375,13 +1387,6 @@
return t;
}
-static int
-isv4str(char *s)
-{- uchar ip[IPaddrlen];
- return parseip(ip, s) != -1 && isv4(ip);
-}
-
static Ndbtuple*
ndbline(Ndbtuple *t)
{@@ -1441,7 +1446,7 @@
*/
t = nil;
if(strcmp(attr, "dom") == 0)
- t = dnsiplookup(host, &s, !np->v4only);
+ t = dnsiplookup(host, &s, np->ipvers);
if(t == nil){ for(nt = ndbsearch(db, &s, attr, host); nt != nil; nt = ndbsnext(&s, attr, host)){ if(ndbfindattr(nt, s.t, "ip") == nil){@@ -1456,12 +1461,12 @@
if(strcmp(attr, "dom") != 0){dnsname = ndbgetvalue(db, &s, attr, host, "dom", nil);
if(dnsname != nil){- t = dnsiplookup(dnsname, &s, !np->v4only);
+ t = dnsiplookup(dnsname, &s, np->ipvers);
free(dnsname);
}
}
if(t == nil)
- t = dnsiplookup(host, &s, !np->v4only);
+ t = dnsiplookup(host, &s, np->ipvers);
}
if(t == nil)
return nil;
@@ -1514,11 +1519,12 @@
* translate an ip address
*/
char*
-iptrans(Ndbtuple *t, Network *np, char *serv, char *rem, int hack)
+iptrans(Ndbtuple *t, Network *np, char *serv, char *rem, int fasttimeout)
{char ts[Maxservice];
char reply[Maxreply];
char x[Maxservice];
+ uchar ip[IPaddrlen];
if(strcmp(t->attr, "ip") != 0)
return nil;
@@ -1537,14 +1543,12 @@
snprint(reply, sizeof(reply), "%s/%s/clone %s%s",
mntpt, np->net, ts, x);
else {- if(np->v4only && !isv4str(t->val))
+ if(parseip(ip, t->val) == -1)
return nil;
-
- if(np->v6only && isv4str(t->val))
+ if((np->ipvers & confipvers & (isv4(ip) ? V4 : V6)) == 0)
return nil;
-
- snprint(reply, sizeof(reply), "%s/%s/clone %s!%s%s%s",
- mntpt, np->net, t->val, ts, x, hack? "!fasttimeout": "");
+ snprint(reply, sizeof(reply), "%s/%s/clone %I!%s%s%s",
+ mntpt, np->net, ip, ts, x, fasttimeout? "!fasttimeout": "");
}
return estrdup(reply);
@@ -1564,7 +1568,7 @@
werrstr("can't translate address");free(ndbgetvalue(db, &s, "sys", host, "telco", &t));
if(t == nil)
- return ndbnew("telco", host);+ return ndbline(ndbnew("telco", host));return ndbreorder(t, s.t);
}
@@ -1682,11 +1686,16 @@
* call the dns process and have it try to translate a name
*/
Ndbtuple*
-dnsiplookup(char *host, Ndbs *s, int v6)
+dnsiplookup(char *host, Ndbs *s, int ipvers)
{char buf[Maxreply];
Ndbtuple *t;
+ ipvers &= confipvers & lookipvers;
+ if(ipvers == 0){+ werrstr("no ip address");+ return nil;
+ }
qunlock(&dblock);
slave(host);
if(*isslave == 0){@@ -1703,9 +1712,10 @@
if(strcmp(ipattr(host), "ip") == 0)
t = dnsquery(mntpt, host, "ptr");
else {- t = dnsquery(mntpt, host, "ip");
- /* special case: query ipv6 (AAAA dns RR) too */
- if (v6 && ipv6lookups)
+ t = nil;
+ if(ipvers & V4)
+ t = dnsquery(mntpt, host, "ip");
+ if(ipvers & V6)
t = dnsip6lookup(mntpt, host, t);
}
s->t = t;
@@ -1811,7 +1821,7 @@
/* give dns a chance */
if((strcmp(attr[0], "dom") == 0 || strcmp(attr[0], "ip") == 0) && val[0]){- t = dnsiplookup(val[0], &s, ipv6lookups);
+ t = dnsiplookup(val[0], &s, lookipvers);
if(t != nil){ if(qmatch(t, attr, val, n)){qreply(mf, t);
@@ -1863,12 +1873,35 @@
return t;
}
+/*
+ * remove duplicates
+ */
+static Ndbtuple*
+ndbdedup(Ndbtuple *t)
+{+ Ndbtuple *tt, *nt, **l;
+
+ for(nt = t; nt != nil; nt = nt->entry){+ for(l = &nt->entry; (tt = *l) != nil;){+ if(strcmp(nt->attr, tt->attr) != 0
+ || strcmp(nt->val, tt->val) != 0){+ l = &tt->entry;
+ continue;
+ }
+ *l = tt->entry;
+ tt->entry = nil;
+ ndbfree(tt);
+ }
+ }
+ return t;
+}
+
char*
ipinfoquery(Mfile *mf, char **list, int n)
{int i, nresolve;
uchar resolve[Maxattr];
- Ndbtuple *t, *nt, *tt, **l;
+ Ndbtuple *t, *nt, **l;
char *attr, *val;
/* skip 'ipinfo' */
@@ -1912,21 +1945,8 @@
if(t == nil)
return "no match";
- /* remove duplicates */
- for(nt = t; nt != nil; nt = nt->entry){- for(l = &nt->entry; (tt = *l) != nil;){- if(strcmp(nt->attr, tt->attr) != 0
- || strcmp(nt->val, tt->val) != 0){- l = &tt->entry;
- continue;
- }
- *l = tt->entry;
- tt->entry = nil;
- ndbfree(tt);
- }
- }
-
if(nresolve != 0){+ t = ndbdedup(t);
for(l = &t; *l != nil;){nt = *l;
@@ -1955,6 +1975,7 @@
ndbfree(nt);
}
}
+ t = ndbdedup(t);
/* make it all one line */
t = ndbline(t);