ref: ad37339a1c39c90f51d273abe60f552d3900f752
dir: /sys/src/cmd/exportfs/oexportfs.c/
/* * oexportfs - legacy exportfs for cpu and import */ #include <u.h> #include <libc.h> #include <auth.h> #include <fcall.h> #include <libsec.h> #define Extern #include "exportfs.h" enum { Encnone, Encssl, Enctls, }; int srvfd = -1; int nonone = 1; char *filterp; char *ealgs = "rc4_256 sha1"; char *aanfilter = "/bin/aan"; int encproto = Encnone; int readonly; static char *anstring = "tcp!*!0"; static void filter(int fd, char *cmd, char *host) { char addr[128], buf[256], *s, *file, *argv[16]; int lfd, p[2], len, argc; if(host == nil){ /* Get a free port and post it to the client. */ if (announce(anstring, addr) < 0) fatal("filter: Cannot announce %s: %r", anstring); snprint(buf, sizeof(buf), "%s/local", addr); if ((lfd = open(buf, OREAD)) < 0) fatal("filter: Cannot open %s: %r", buf); if ((len = read(lfd, buf, sizeof buf - 1)) < 0) fatal("filter: Cannot read %s: %r", buf); close(lfd); buf[len] = '\0'; if ((s = strchr(buf, '\n')) != nil) len = s - buf; if (write(fd, buf, len) != len) fatal("filter: cannot write port; %r"); } else { /* Read address string from connection */ if ((len = read(fd, buf, sizeof buf - 1)) < 0) sysfatal("filter: cannot write port; %r"); buf[len] = '\0'; if ((s = strrchr(buf, '!')) == nil) sysfatal("filter: illegally formatted port %s", buf); strecpy(addr, addr+sizeof(addr), netmkaddr(host, "tcp", s+1)); strecpy(strrchr(addr, '!'), addr+sizeof(addr), s); } DEBUG(DFD, "filter: %s\n", addr); snprint(buf, sizeof(buf), "%s", cmd); argc = tokenize(buf, argv, nelem(argv)-3); if (argc == 0) sysfatal("filter: empty command"); if(host != nil) argv[argc++] = "-c"; argv[argc++] = addr; argv[argc] = nil; file = argv[0]; if((s = strrchr(argv[0], '/')) != nil) argv[0] = s+1; if(pipe(p) < 0) sysfatal("pipe: %r"); switch(rfork(RFNOWAIT|RFPROC|RFMEM|RFFDG|RFREND)) { case -1: fatal("filter: rfork; %r\n"); case 0: close(fd); if (dup(p[0], 1) < 0) fatal("filter: Cannot dup to 1; %r"); if (dup(p[0], 0) < 0) fatal("filter: Cannot dup to 0; %r"); close(p[0]); close(p[1]); exec(file, argv); fatal("filter: exec; %r"); default: dup(p[1], fd); close(p[0]); close(p[1]); } } static void mksecret(char *t, uchar *f) { sprint(t, "%2.2ux%2.2ux%2.2ux%2.2ux%2.2ux%2.2ux%2.2ux%2.2ux%2.2ux%2.2ux", f[0], f[1], f[2], f[3], f[4], f[5], f[6], f[7], f[8], f[9]); } void usage(void) { fprint(2, "usage: %s [-adnsR] [-f dbgfile] [-m msize] [-r root] " "[-S srvfile] [-e 'crypt hash'] [-P exclusion-file] " "[-A announce-string] [-B address]\n", argv0); fatal("usage"); } void main(int argc, char **argv) { char buf[ERRMAX], ebuf[ERRMAX], initial[4], *ini, *srvfdfile; char *dbfile, *srv, *na, *nsfile, *keyspec; int doauth, n, fd; AuthInfo *ai; Fsrpc *r; dbfile = "/tmp/exportdb"; srv = nil; srvfd = -1; srvfdfile = nil; na = nil; nsfile = nil; keyspec = ""; doauth = 0; ai = nil; ARGBEGIN{ case 'a': doauth = 1; break; case 'd': dbg++; break; case 'e': ealgs = EARGF(usage()); if(*ealgs == 0 || strcmp(ealgs, "clear") == 0) ealgs = nil; break; case 'f': dbfile = EARGF(usage()); break; case 'k': keyspec = EARGF(usage()); break; case 'm': messagesize = strtoul(EARGF(usage()), nil, 0); break; case 'n': nonone = 0; break; case 'r': srv = EARGF(usage()); break; case 's': srv = "/"; break; case 'A': anstring = EARGF(usage()); break; case 'B': na = EARGF(usage()); break; case 'F': /* accepted but ignored, for backwards compatibility */ break; case 'N': nsfile = EARGF(usage()); break; case 'P': patternfile = EARGF(usage()); break; case 'R': readonly = 1; break; case 'S': if(srvfdfile != nil) usage(); srvfdfile = EARGF(usage()); break; default: usage(); }ARGEND USED(argc, argv); if(na == nil && doauth){ /* * We use p9any so we don't have to visit this code again, with the * cost that this code is incompatible with the old world, which * requires p9sk2. (The two differ in who talks first, so compatibility * is awkward.) */ ai = auth_proxy(0, auth_getkey, "proto=p9any role=server %s", keyspec); if(ai == nil) fatal("auth_proxy: %r"); if(nonone && strcmp(ai->cuid, "none") == 0) fatal("exportfs by none disallowed"); if(auth_chuid(ai, nsfile) < 0) fatal("auth_chuid: %r"); else { /* chown network connection */ Dir nd; nulldir(&nd); nd.mode = 0660; nd.uid = ai->cuid; dirfwstat(0, &nd); } putenv("service", "exportfs"); } if(srvfdfile != nil){ if((srvfd = open(srvfdfile, ORDWR)) < 0) fatal("open %s: %r", srvfdfile); } if(na != nil){ if(srv == nil) fatal("-B requires -s"); if((fd = dial(netmkaddr(na, 0, "importfs"), 0, 0, 0)) < 0) fatal("can't dial %s: %r", na); ai = auth_proxy(fd, auth_getkey, "proto=p9any role=client %s", keyspec); if(ai == nil) fatal("%r: %s", na); dup(fd, 0); dup(fd, 1); close(fd); } exclusions(); if(dbg) { n = create(dbfile, OWRITE|OTRUNC, 0666); dup(n, DFD); close(n); } if(srvfd >= 0 && srv != nil){ fprint(2, "%s: -S cannot be used with -r or -s\n", argv0); usage(); } DEBUG(DFD, "%s: started\n", argv0); rfork(RFNOTEG|RFREND); if(messagesize == 0){ messagesize = iounit(0); if(messagesize == 0) messagesize = 8192+IOHDRSZ; } fhash = emallocz(sizeof(Fid*)*FHASHSIZE); fmtinstall('F', fcallfmt); /* * Get tree to serve from network connection, * check we can get there and ack the connection */ if(srvfd != -1) { /* do nothing */ } else if(srv != nil) { if(chdir(srv) < 0) { ebuf[0] = '\0'; errstr(ebuf, sizeof ebuf); DEBUG(DFD, "chdir(\"%s\"): %s\n", srv, ebuf); mounterror(ebuf); } DEBUG(DFD, "invoked as server for %s", srv); strncpy(buf, srv, sizeof buf); } else { buf[0] = 0; n = read(0, buf, sizeof(buf)-1); if(n < 0) { errstr(buf, sizeof buf); fprint(0, "read(0): %s\n", buf); DEBUG(DFD, "read(0): %s\n", buf); exits(buf); } buf[n] = 0; if(chdir(buf) < 0) { errstr(ebuf, sizeof ebuf); fprint(0, "chdir(%d:\"%s\"): %s\n", n, buf, ebuf); DEBUG(DFD, "chdir(%d:\"%s\"): %s\n", n, buf, ebuf); exits(ebuf); } } DEBUG(DFD, "\niniting root\n"); initroot(); DEBUG(DFD, "%s: %s\n", argv0, buf); if(srv == nil && srvfd == -1 && write(0, "OK", 2) != 2) fatal("open ack write"); ini = initial; n = readn(0, initial, sizeof(initial)); if(n == 0) fatal(nil); /* port scan or spurious open/close on exported /srv file (unmount) */ if(n < sizeof(initial)) fatal("can't read initial string: %r"); if(memcmp(ini, "impo", 4) == 0) { char buf[128], *p, *args[3]; ini = nil; p = buf; for(;;){ if((n = read(0, p, 1)) < 0) fatal("can't read impo arguments: %r"); if(n == 0) fatal("connection closed while reading arguments"); if(*p == '\n') *p = '\0'; if(*p++ == '\0') break; if(p >= buf + sizeof(buf)) fatal("import parameters too long"); } if(tokenize(buf, args, nelem(args)) != 2) fatal("impo arguments invalid: impo%s...", buf); if(strcmp(args[0], "aan") == 0) filterp = aanfilter; else if(strcmp(args[0], "nofilter") != 0) fatal("import filter argument unsupported: %s", args[0]); if(strcmp(args[1], "ssl") == 0) encproto = Encssl; else if(strcmp(args[1], "tls") == 0) encproto = Enctls; else if(strcmp(args[1], "clear") != 0) fatal("import encryption proto unsupported: %s", args[1]); if(encproto == Enctls) fatal("%s: tls has not yet been implemented", argv[0]); } if(encproto != Encnone && ealgs != nil && ai != nil) { uchar key[16], digest[SHA1dlen]; char fromclientsecret[21]; char fromserversecret[21]; int i; if(ai->nsecret < 8) fatal("secret too small for ssl"); memmove(key+4, ai->secret, 8); /* exchange random numbers */ srand(truerand()); for(i = 0; i < 4; i++) key[i+12] = rand(); if(ini != nil) fatal("Protocol botch: old import"); if(readn(0, key, 4) != 4) fatal("can't read key part; %r"); if(write(0, key+12, 4) != 4) fatal("can't write key part; %r"); /* scramble into two secrets */ sha1(key, sizeof(key), digest, nil); mksecret(fromclientsecret, digest); mksecret(fromserversecret, digest+10); if(filterp != nil) filter(0, filterp, na); switch(encproto) { case Encssl: fd = pushssl(0, ealgs, fromserversecret, fromclientsecret, nil); if(fd < 0) fatal("can't establish ssl connection: %r"); if(fd != 0){ dup(fd, 0); close(fd); } break; case Enctls: default: fatal("Unsupported encryption protocol"); } } else if(filterp != nil) { if(ini != nil) fatal("Protocol botch: don't know how to deal with this"); filter(0, filterp, na); } dup(0, 1); if(ai != nil) auth_freeAI(ai); if(ini != nil){ extern void (*fcalls[])(Fsrpc*); r = getsbuf(); memmove(r->buf, ini, BIT32SZ); n = GBIT32(r->buf); if(n <= BIT32SZ || n > messagesize) fatal("bad length in 9P2000 message header"); n -= BIT32SZ; if(readn(0, r->buf+BIT32SZ, n) != n) fatal(nil); n += BIT32SZ; if(convM2S(r->buf, n, &r->work) != n) fatal("convM2S format error"); DEBUG(DFD, "%F\n", &r->work); (fcalls[r->work.type])(r); } io(); }