ref: dde3628d54073e0569bf565e6ec861e42cfa35f6
dir: /sys/src/cmd/ratfs/ctlfiles.c/
#include "ratfs.h" enum { ACCEPT = 0, /* verbs in control file */ REFUSED, DENIED, DIALUP, BLOCKED, DELAY, NONE, Subchar = '#', /* character substituted for '/' in file names */ }; static Keyword actions[] = { "allow", ACCEPT, "accept", ACCEPT, "block", BLOCKED, "deny", DENIED, "dial", DIALUP, "relay", DELAY, "delay", DELAY, 0, NONE, }; static void acctinsert(Node*, char*); static char* getline(Biobuf*); static void ipinsert(Node*, char*); static void ipsort(void); /* * Input the configuration file * Currently we only process the "ournets" * specification. */ void getconf(void) { Biobuf *bp; char *cp; Node *np, *dir, **l; Cidraddr ip; if(debugfd >= 0) fprint(debugfd, "loading %s\n", conffile); bp = Bopen(conffile, OREAD); if(bp == 0) return; dir = finddir(Trusted); if(dir == 0) return; /* * if this isn't the first time, purge permanent entries */ trustedqid = Qtrustedfile; if(lastconftime){ l = &dir->children; for(np = dir->children; np; np = *l){ if(np->d.type == Trustedperm){ *l = np->sibs; free(np); } else { np->d.qid.path = trustedqid++; l = &np->sibs; } } dir->count = 0; } for(;;){ cp = getline(bp); if(cp == 0) break; if (strcmp(cp, "ournets") == 0){ for(cp += strlen(cp)+1; cp && *cp; cp += strlen(cp)+1){ if(cidrparse(&ip, cp) == -1) continue; np = newnode(dir, cp, Trustedperm, 0111, trustedqid++); np->ip = ip; subslash(cp); np->d.name = atom(cp); } } } Bterm(bp); lastconftime = time(0); } /* * Reload the control file, if necessary */ void reload(void) { int type, action; Biobuf *bp; char *cp; Node *np, *dir; if(debugfd >= 0) fprint(debugfd,"loading %s\n", ctlfile); bp = Bopen(ctlfile, OREAD); if(bp == 0) return; if(lastctltime){ for(dir = root->children; dir; dir = dir->sibs){ if (dir->d.type != Addrdir) continue; for(np = dir->children; np; np = np->sibs) np->count = 0; } } for(;;){ cp = getline(bp); if(cp == 0) break; type = *cp; if(type == '*'){ cp++; if(*cp == 0) /* space before keyword */ cp++; } action = findkey(cp, actions); if (action == NONE) continue; if (action == ACCEPT) dir = dirwalk("allow", root); else if (action == DELAY) dir = dirwalk("delay", root); else dir = dirwalk(cp, root); if(dir == 0) continue; for(cp += strlen(cp)+1; cp && *cp; cp += strlen(cp)+1){ if(type == '*') acctinsert(dir, cp); else ipinsert(dir, cp); } } Bterm(bp); ipsort(); dummy.d.mtime = dummy.d.atime = lastctltime = time(0); } /* * get a canonicalized line: a string of null-terminated lower-case * tokens with a two null bytes at the end. */ static char* getline(Biobuf *bp) { char c, *cp, *p, *q; int n; static char *buf; static int bufsize; for(;;){ cp = Brdline(bp, '\n'); if(cp == 0) return 0; n = Blinelen(bp); cp[n-1] = 0; if(buf == 0 || bufsize < n+1){ bufsize += 512; if(bufsize < n+1) bufsize = n+1; buf = realloc(buf, bufsize); if(buf == 0) break; } q = buf; for (p = cp; *p; p++){ c = *p; if(c == '\\' && p[1]) /* we don't allow \<newline> */ c = *++p; else if(c == '#') break; else if(c == ' ' || c == '\t' || c == ',') if(q == buf || q[-1] == 0) continue; else c = 0; *q++ = tolower(c); } if(q != buf){ if(q[-1]) *q++ = 0; *q = 0; break; } } return buf; } /* * Match a keyword */ int findkey(char *val, Keyword *p) { for(; p->name; p++) if(strcmp(val, p->name) == 0) break; return p->code; } /* * parse a cidr specification in either IP/mask or IP#mask format */ int cidrparse(Cidraddr *cidr, char *cp) { uchar ip[IPaddrlen]; char buf[64], *p, *slash; int c; /* * find '/' or '#' character in the cidr specification */ slash = 0; for(p = buf; p < buf+sizeof(buf)-1 && *cp; p++) { c = *cp++; switch(c) { case Subchar: c = '/'; slash = p; break; case '/': slash = p; break; default: break; } *p = c; } *p = 0; if(parseipandmask(ip, cidr->mask, buf, slash) == -1) return -1; maskip(ip, cidr->mask, cidr->ipaddr); return 0; } /* * Substitute Subchar ('#') for '/' */ char* subslash(char *os) { char *s; for(s=os; *s; s++) if(*s == '/') *s = Subchar; return os; } /* * Insert an account pseudo-file in a directory */ static void acctinsert(Node *np, char *cp) { int i; char *tmp; Address *ap; static char *dangerous[] = { "*", "!", "*!", "!*", "*!*", 0 }; if(cp == 0 || *cp == 0) return; /* rule out dangerous patterns */ for (i = 0; dangerous[i]; i++) if(strcmp(cp, dangerous[i])== 0) return; np = dirwalk("account", np); if(np == 0) return; i = np->count++; if(i >= np->allocated){ np->allocated = np->count; np->addrs = realloc(np->addrs, np->allocated*sizeof(Address)); if(np->addrs == 0) fatal("out of memory"); } ap = &np->addrs[i]; /* new entry on end */ tmp = strdup(cp); if(tmp == nil) fatal("out of memory"); subslash(tmp); ap->name = atom(tmp); free(tmp); } /* * Insert an IP address pseudo-file in a directory */ static void ipinsert(Node *np, char *cp) { char *tmp; int i; Address *ap; Cidraddr ip; if(cp == 0 || *cp == 0 || cidrparse(&ip, cp) == -1) return; np = dirwalk("ip", np); if(np == 0) return; i = np->count++; if(i >= np->allocated){ np->allocated = np->count; np->addrs = realloc(np->addrs, np->allocated*sizeof(Address)); if(np->addrs == 0) fatal("out of memory"); } ap = &np->addrs[i]; /* new entry on end */ ap->ip = ip; tmp = strdup(cp); if(tmp == nil) fatal("out of memory"); subslash(tmp); ap->name = atom(tmp); free(tmp); } static int ipaddrcomp(void *a, void *b) { return ipcmp(((Address*)a)->ip.ipaddr, ((Address*)b)->ip.ipaddr); } /* * Sort a directory of IP addresses */ static void ipsort(void) { int base; Node *dir, *np; base = Qaddrfile; for(dir = root->children; dir; dir = dir->sibs){ if (dir->d.type != Addrdir) continue; for(np = dir->children; np; np = np->sibs){ if(np->d.type == IPaddr && np->count && np->addrs) qsort(np->addrs, np->count, sizeof(Address), ipaddrcomp); np->baseqid = base; base += np->count; } } }