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Diffstat (limited to 'src/cmd/auth/factotum/cpu.c')
-rw-r--r--src/cmd/auth/factotum/cpu.c1117
1 files changed, 1117 insertions, 0 deletions
diff --git a/src/cmd/auth/factotum/cpu.c b/src/cmd/auth/factotum/cpu.c
new file mode 100644
index 00000000..da8280ad
--- /dev/null
+++ b/src/cmd/auth/factotum/cpu.c
@@ -0,0 +1,1117 @@
+/*
+ * cpu.c - Make a connection to a cpu server
+ *
+ * Invoked by listen as 'cpu -R | -N service net netdir'
+ * by users as 'cpu [-h system] [-c cmd args ...]'
+ */
+
+#include <u.h>
+#include <libc.h>
+#include <bio.h>
+#include <auth.h>
+#include <fcall.h>
+#include <libsec.h>
+
+#define Maxfdata 8192
+
+void remoteside(int);
+void fatal(int, char*, ...);
+void lclnoteproc(int);
+void rmtnoteproc(void);
+void catcher(void*, char*);
+void usage(void);
+void writestr(int, char*, char*, int);
+int readstr(int, char*, int);
+char *rexcall(int*, char*, char*);
+int setamalg(char*);
+
+int notechan;
+char system[32];
+int cflag;
+int hflag;
+int dbg;
+char *user;
+
+char *srvname = "ncpu";
+char *exportfs = "/bin/exportfs";
+char *ealgs = "rc4_256 sha1";
+
+/* message size for exportfs; may be larger so we can do big graphics in CPU window */
+int msgsize = 8192+IOHDRSZ;
+
+/* authentication mechanisms */
+static int netkeyauth(int);
+static int netkeysrvauth(int, char*);
+static int p9auth(int);
+static int srvp9auth(int, char*);
+static int noauth(int);
+static int srvnoauth(int, char*);
+
+typedef struct AuthMethod AuthMethod;
+struct AuthMethod {
+ char *name; /* name of method */
+ int (*cf)(int); /* client side authentication */
+ int (*sf)(int, char*); /* server side authentication */
+} authmethod[] =
+{
+ { "p9", p9auth, srvp9auth,},
+ { "netkey", netkeyauth, netkeysrvauth,},
+// { "none", noauth, srvnoauth,},
+ { nil, nil}
+};
+AuthMethod *am = authmethod; /* default is p9 */
+
+char *p9authproto = "p9any";
+
+int setam(char*);
+
+void
+usage(void)
+{
+ fprint(2, "usage: cpu [-h system] [-a authmethod] [-e 'crypt hash'] [-c cmd args ...]\n");
+ exits("usage");
+}
+int fdd;
+
+void
+main(int argc, char **argv)
+{
+ char dat[128], buf[128], cmd[128], *p, *err;
+ int fd, ms, kms, data;
+
+ /* see if we should use a larger message size */
+ fd = open("/dev/draw", OREAD);
+ if(fd > 0){
+ ms = iounit(fd);
+ if(ms != 0 && ms < ms+IOHDRSZ)
+ msgsize = ms+IOHDRSZ;
+ close(fd);
+ }
+ kms = kiounit();
+ if(msgsize > kms-IOHDRSZ-100) /* 100 for network packets, etc. */
+ msgsize = kms-IOHDRSZ-100;
+
+ user = getuser();
+ if(user == nil)
+ fatal(1, "can't read user name");
+ ARGBEGIN{
+ case 'a':
+ p = EARGF(usage());
+ if(setam(p) < 0)
+ fatal(0, "unknown auth method %s", p);
+ break;
+ case 'e':
+ ealgs = EARGF(usage());
+ if(*ealgs == 0 || strcmp(ealgs, "clear") == 0)
+ ealgs = nil;
+ break;
+ case 'd':
+ dbg++;
+ break;
+ case 'f':
+ /* ignored but accepted for compatibility */
+ break;
+ case 'O':
+ p9authproto = "p9sk2";
+ remoteside(1); /* From listen */
+ break;
+ case 'R': /* From listen */
+ remoteside(0);
+ break;
+ case 'h':
+ hflag++;
+ p = EARGF(usage());
+ strcpy(system, p);
+ break;
+ case 'c':
+ cflag++;
+ cmd[0] = '!';
+ cmd[1] = '\0';
+ while(p = ARGF()) {
+ strcat(cmd, " ");
+ strcat(cmd, p);
+ }
+ break;
+ case 'o':
+ p9authproto = "p9sk2";
+ srvname = "cpu";
+ break;
+ case 'u':
+ user = EARGF(usage());
+ break;
+ default:
+ usage();
+ }ARGEND;
+
+
+ if(argc != 0)
+ usage();
+
+ if(hflag == 0) {
+ p = getenv("cpu");
+ if(p == 0)
+ fatal(0, "set $cpu");
+ strcpy(system, p);
+ }
+
+ if(err = rexcall(&data, system, srvname))
+ fatal(1, "%s: %s", err, system);
+
+ /* Tell the remote side the command to execute and where our working directory is */
+ if(cflag)
+ writestr(data, cmd, "command", 0);
+ if(getwd(dat, sizeof(dat)) == 0)
+ writestr(data, "NO", "dir", 0);
+ else
+ writestr(data, dat, "dir", 0);
+
+ /* start up a process to pass along notes */
+ lclnoteproc(data);
+
+ /*
+ * Wait for the other end to execute and start our file service
+ * of /mnt/term
+ */
+ if(readstr(data, buf, sizeof(buf)) < 0)
+ fatal(1, "waiting for FS");
+ if(strncmp("FS", buf, 2) != 0) {
+ print("remote cpu: %s", buf);
+ exits(buf);
+ }
+
+ /* Begin serving the gnot namespace */
+ close(0);
+ dup(data, 0);
+ close(data);
+ sprint(buf, "%d", msgsize);
+ if(dbg)
+ execl(exportfs, exportfs, "-dm", buf, 0);
+ else
+ execl(exportfs, exportfs, "-m", buf, 0);
+ fatal(1, "starting exportfs");
+}
+
+void
+fatal(int syserr, char *fmt, ...)
+{
+ char buf[ERRMAX];
+ va_list arg;
+
+ va_start(arg, fmt);
+ doprint(buf, buf+sizeof(buf), fmt, arg);
+ va_end(arg);
+ if(syserr)
+ fprint(2, "cpu: %s: %r\n", buf);
+ else
+ fprint(2, "cpu: %s\n", buf);
+ exits(buf);
+}
+
+char *negstr = "negotiating authentication method";
+
+char bug[256];
+
+int
+old9p(int fd)
+{
+ int p[2];
+
+ if(pipe(p) < 0)
+ fatal(1, "pipe");
+
+ switch(rfork(RFPROC|RFFDG|RFNAMEG)) {
+ case -1:
+ fatal(1, "rfork srvold9p");
+ case 0:
+ if(fd != 1){
+ dup(fd, 1);
+ close(fd);
+ }
+ if(p[0] != 0){
+ dup(p[0], 0);
+ close(p[0]);
+ }
+ close(p[1]);
+ if(0){
+ fd = open("/sys/log/cpu", OWRITE);
+ if(fd != 2){
+ dup(fd, 2);
+ close(fd);
+ }
+ execl("/bin/srvold9p", "srvold9p", "-ds", 0);
+ } else
+ execl("/bin/srvold9p", "srvold9p", "-s", 0);
+ fatal(1, "exec srvold9p");
+ default:
+ close(fd);
+ close(p[0]);
+ }
+ return p[1];
+}
+
+/* Invoked with stdin, stdout and stderr connected to the network connection */
+void
+remoteside(int old)
+{
+ char user[128], home[128], buf[128], xdir[128], cmd[128];
+ int i, n, fd, badchdir, gotcmd;
+
+ fd = 0;
+
+ /* negotiate authentication mechanism */
+ n = readstr(fd, cmd, sizeof(cmd));
+ if(n < 0)
+ fatal(1, "authenticating");
+ if(setamalg(cmd) < 0){
+ writestr(fd, "unsupported auth method", nil, 0);
+ fatal(1, "bad auth method %s", cmd);
+ } else
+ writestr(fd, "", "", 1);
+
+ fd = (*am->sf)(fd, user);
+ if(fd < 0)
+ fatal(1, "srvauth");
+
+ /* Set environment values for the user */
+ putenv("user", user);
+ sprint(home, "/usr/%s", user);
+ putenv("home", home);
+
+ /* Now collect invoking cpu's current directory or possibly a command */
+ gotcmd = 0;
+ if(readstr(fd, xdir, sizeof(xdir)) < 0)
+ fatal(1, "dir/cmd");
+ if(xdir[0] == '!') {
+ strcpy(cmd, &xdir[1]);
+ gotcmd = 1;
+ if(readstr(fd, xdir, sizeof(xdir)) < 0)
+ fatal(1, "dir");
+ }
+
+ /* Establish the new process at the current working directory of the
+ * gnot */
+ badchdir = 0;
+ if(strcmp(xdir, "NO") == 0)
+ chdir(home);
+ else if(chdir(xdir) < 0) {
+ badchdir = 1;
+ chdir(home);
+ }
+
+ /* Start the gnot serving its namespace */
+ writestr(fd, "FS", "FS", 0);
+ writestr(fd, "/", "exportfs dir", 0);
+
+ n = read(fd, buf, sizeof(buf));
+ if(n != 2 || buf[0] != 'O' || buf[1] != 'K')
+ exits("remote tree");
+
+ if(old)
+ fd = old9p(fd);
+
+ /* make sure buffers are big by doing fversion explicitly; pick a huge number; other side will trim */
+ strcpy(buf, VERSION9P);
+ if(fversion(fd, 64*1024, buf, sizeof buf) < 0)
+ exits("fversion failed");
+ if(mount(fd, -1, "/mnt/term", MCREATE|MREPL, "") < 0)
+ exits("mount failed");
+
+ close(fd);
+
+ /* the remote noteproc uses the mount so it must follow it */
+ rmtnoteproc();
+
+ for(i = 0; i < 3; i++)
+ close(i);
+
+ if(open("/mnt/term/dev/cons", OREAD) != 0)
+ exits("open stdin");
+ if(open("/mnt/term/dev/cons", OWRITE) != 1)
+ exits("open stdout");
+ dup(1, 2);
+
+ if(badchdir)
+ print("cpu: failed to chdir to '%s'\n", xdir);
+
+ if(gotcmd)
+ execl("/bin/rc", "rc", "-lc", cmd, 0);
+ else
+ execl("/bin/rc", "rc", "-li", 0);
+ fatal(1, "exec shell");
+}
+
+char*
+rexcall(int *fd, char *host, char *service)
+{
+ char *na;
+ char dir[128];
+ char err[ERRMAX];
+ char msg[128];
+ int n;
+
+ na = netmkaddr(host, 0, service);
+ if((*fd = dial(na, 0, dir, 0)) < 0)
+ return "can't dial";
+
+ /* negotiate authentication mechanism */
+ if(ealgs != nil)
+ snprint(msg, sizeof(msg), "%s %s", am->name, ealgs);
+ else
+ snprint(msg, sizeof(msg), "%s", am->name);
+ writestr(*fd, msg, negstr, 0);
+ n = readstr(*fd, err, sizeof err);
+ if(n < 0)
+ return negstr;
+ if(*err){
+ werrstr(err);
+ return negstr;
+ }
+
+ /* authenticate */
+ *fd = (*am->cf)(*fd);
+ if(*fd < 0)
+ return "can't authenticate";
+ return 0;
+}
+
+void
+writestr(int fd, char *str, char *thing, int ignore)
+{
+ int l, n;
+
+ l = strlen(str);
+ n = write(fd, str, l+1);
+ if(!ignore && n < 0)
+ fatal(1, "writing network: %s", thing);
+}
+
+int
+readstr(int fd, char *str, int len)
+{
+ int n;
+
+ while(len) {
+ n = read(fd, str, 1);
+ if(n < 0)
+ return -1;
+ if(*str == '\0')
+ return 0;
+ str++;
+ len--;
+ }
+ return -1;
+}
+
+static int
+readln(char *buf, int n)
+{
+ char *p = buf;
+
+ n--;
+ while(n > 0){
+ if(read(0, p, 1) != 1)
+ break;
+ if(*p == '\n' || *p == '\r'){
+ *p = 0;
+ return p-buf;
+ }
+ p++;
+ }
+ *p = 0;
+ return p-buf;
+}
+
+/*
+ * user level challenge/response
+ */
+static int
+netkeyauth(int fd)
+{
+ char chall[32];
+ char resp[32];
+
+ strcpy(chall, getuser());
+ print("user[%s]: ", chall);
+ if(readln(resp, sizeof(resp)) < 0)
+ return -1;
+ if(*resp != 0)
+ strcpy(chall, resp);
+ writestr(fd, chall, "challenge/response", 1);
+
+ for(;;){
+ if(readstr(fd, chall, sizeof chall) < 0)
+ break;
+ if(*chall == 0)
+ return fd;
+ print("challenge: %s\nresponse: ", chall);
+ if(readln(resp, sizeof(resp)) < 0)
+ break;
+ writestr(fd, resp, "challenge/response", 1);
+ }
+ return -1;
+}
+
+static int
+netkeysrvauth(int fd, char *user)
+{
+ char response[32];
+ Chalstate *ch;
+ int tries;
+ AuthInfo *ai;
+
+ if(readstr(fd, user, 32) < 0)
+ return -1;
+
+ ai = nil;
+ ch = nil;
+ for(tries = 0; tries < 10; tries++){
+ if((ch = auth_challenge("p9cr", user, nil)) == nil)
+ return -1;
+ writestr(fd, ch->chal, "challenge", 1);
+ if(readstr(fd, response, sizeof response) < 0)
+ return -1;
+ ch->resp = response;
+ ch->nresp = strlen(response);
+ if((ai = auth_response(ch)) != nil)
+ break;
+ }
+ auth_freechal(ch);
+ if(ai == nil)
+ return -1;
+ writestr(fd, "", "challenge", 1);
+ if(auth_chuid(ai, 0) < 0)
+ fatal(1, "newns");
+ auth_freeAI(ai);
+ return fd;
+}
+
+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]);
+}
+
+/*
+ * plan9 authentication followed by rc4 encryption
+ */
+static int
+p9auth(int fd)
+{
+ uchar key[16];
+ uchar digest[SHA1dlen];
+ char fromclientsecret[21];
+ char fromserversecret[21];
+ int i;
+ AuthInfo *ai;
+
+ ai = auth_proxy(fd, auth_getkey, "proto=%q user=%q role=client", p9authproto, user);
+ if(ai == nil)
+ return -1;
+ memmove(key+4, ai->secret, ai->nsecret);
+ if(ealgs == nil)
+ return fd;
+
+ /* exchange random numbers */
+ srand(truerand());
+ for(i = 0; i < 4; i++)
+ key[i] = rand();
+ if(write(fd, key, 4) != 4)
+ return -1;
+ if(readn(fd, key+12, 4) != 4)
+ return -1;
+
+ /* scramble into two secrets */
+ sha1(key, sizeof(key), digest, nil);
+ mksecret(fromclientsecret, digest);
+ mksecret(fromserversecret, digest+10);
+
+ /* set up encryption */
+ i = pushssl(fd, ealgs, fromclientsecret, fromserversecret, nil);
+ if(i < 0)
+ werrstr("can't establish ssl connection: %r");
+ return i;
+}
+
+static int
+noauth(int fd)
+{
+ ealgs = nil;
+ return fd;
+}
+
+static int
+srvnoauth(int fd, char *user)
+{
+ strcpy(user, getuser());
+ ealgs = nil;
+ return fd;
+}
+
+void
+loghex(uchar *p, int n)
+{
+ char buf[100];
+ int i;
+
+ for(i = 0; i < n; i++)
+ sprint(buf+2*i, "%2.2ux", p[i]);
+ syslog(0, "cpu", buf);
+}
+
+static int
+srvp9auth(int fd, char *user)
+{
+ uchar key[16];
+ uchar digest[SHA1dlen];
+ char fromclientsecret[21];
+ char fromserversecret[21];
+ int i;
+ AuthInfo *ai;
+
+ ai = auth_proxy(0, nil, "proto=%q role=server", p9authproto);
+ if(ai == nil)
+ return -1;
+ if(auth_chuid(ai, nil) < 0)
+ return -1;
+ strcpy(user, ai->cuid);
+ memmove(key+4, ai->secret, ai->nsecret);
+
+ if(ealgs == nil)
+ return fd;
+
+ /* exchange random numbers */
+ srand(truerand());
+ for(i = 0; i < 4; i++)
+ key[i+12] = rand();
+ if(readn(fd, key, 4) != 4)
+ return -1;
+ if(write(fd, key+12, 4) != 4)
+ return -1;
+
+ /* scramble into two secrets */
+ sha1(key, sizeof(key), digest, nil);
+ mksecret(fromclientsecret, digest);
+ mksecret(fromserversecret, digest+10);
+
+ /* set up encryption */
+ i = pushssl(fd, ealgs, fromserversecret, fromclientsecret, nil);
+ if(i < 0)
+ werrstr("can't establish ssl connection: %r");
+ return i;
+}
+
+/*
+ * set authentication mechanism
+ */
+int
+setam(char *name)
+{
+ for(am = authmethod; am->name != nil; am++)
+ if(strcmp(am->name, name) == 0)
+ return 0;
+ am = authmethod;
+ return -1;
+}
+
+/*
+ * set authentication mechanism and encryption/hash algs
+ */
+int
+setamalg(char *s)
+{
+ ealgs = strchr(s, ' ');
+ if(ealgs != nil)
+ *ealgs++ = 0;
+ return setam(s);
+}
+
+char *rmtnotefile = "/mnt/term/dev/cpunote";
+
+/*
+ * loop reading /mnt/term/dev/note looking for notes.
+ * The child returns to start the shell.
+ */
+void
+rmtnoteproc(void)
+{
+ int n, fd, pid, notepid;
+ char buf[256];
+
+ /* new proc returns to start shell */
+ pid = rfork(RFPROC|RFFDG|RFNOTEG|RFNAMEG|RFMEM);
+ switch(pid){
+ case -1:
+ syslog(0, "cpu", "cpu -R: can't start noteproc: %r");
+ return;
+ case 0:
+ return;
+ }
+
+ /* new proc reads notes from other side and posts them to shell */
+ switch(notepid = rfork(RFPROC|RFFDG|RFMEM)){
+ case -1:
+ syslog(0, "cpu", "cpu -R: can't start wait proc: %r");
+ _exits(0);
+ case 0:
+ fd = open(rmtnotefile, OREAD);
+ if(fd < 0){
+ syslog(0, "cpu", "cpu -R: can't open %s", rmtnotefile);
+ _exits(0);
+ }
+
+ for(;;){
+ n = read(fd, buf, sizeof(buf)-1);
+ if(n <= 0){
+ postnote(PNGROUP, pid, "hangup");
+ _exits(0);
+ }
+ buf[n] = 0;
+ postnote(PNGROUP, pid, buf);
+ }
+ break;
+ }
+
+ /* original proc waits for shell proc to die and kills note proc */
+ for(;;){
+ n = waitpid();
+ if(n < 0 || n == pid)
+ break;
+ }
+ postnote(PNPROC, notepid, "kill");
+ _exits(0);
+}
+
+enum
+{
+ Qdir,
+ Qcpunote,
+
+ Nfid = 32,
+};
+
+struct {
+ char *name;
+ Qid qid;
+ ulong perm;
+} fstab[] =
+{
+ [Qdir] { ".", {Qdir, 0, QTDIR}, DMDIR|0555 },
+ [Qcpunote] { "cpunote", {Qcpunote, 0}, 0444 },
+};
+
+typedef struct Note Note;
+struct Note
+{
+ Note *next;
+ char msg[ERRMAX];
+};
+
+typedef struct Request Request;
+struct Request
+{
+ Request *next;
+ Fcall f;
+};
+
+typedef struct Fid Fid;
+struct Fid
+{
+ int fid;
+ int file;
+};
+Fid fids[Nfid];
+
+struct {
+ Lock;
+ Note *nfirst, *nlast;
+ Request *rfirst, *rlast;
+} nfs;
+
+int
+fsreply(int fd, Fcall *f)
+{
+ uchar buf[IOHDRSZ+Maxfdata];
+ int n;
+
+ if(dbg)
+ fprint(2, "<-%F\n", f);
+ n = convS2M(f, buf, sizeof buf);
+ if(n > 0){
+ if(write(fd, buf, n) != n){
+ close(fd);
+ return -1;
+ }
+ }
+ return 0;
+}
+
+/* match a note read request with a note, reply to the request */
+int
+kick(int fd)
+{
+ Request *rp;
+ Note *np;
+ int rv;
+
+ for(;;){
+ lock(&nfs);
+ rp = nfs.rfirst;
+ np = nfs.nfirst;
+ if(rp == nil || np == nil){
+ unlock(&nfs);
+ break;
+ }
+ nfs.rfirst = rp->next;
+ nfs.nfirst = np->next;
+ unlock(&nfs);
+
+ rp->f.type = Rread;
+ rp->f.count = strlen(np->msg);
+ rp->f.data = np->msg;
+ rv = fsreply(fd, &rp->f);
+ free(rp);
+ free(np);
+ if(rv < 0)
+ return -1;
+ }
+ return 0;
+}
+
+void
+flushreq(int tag)
+{
+ Request **l, *rp;
+
+ lock(&nfs);
+ for(l = &nfs.rfirst; *l != nil; l = &(*l)->next){
+ rp = *l;
+ if(rp->f.tag == tag){
+ *l = rp->next;
+ unlock(&nfs);
+ free(rp);
+ return;
+ }
+ }
+ unlock(&nfs);
+}
+
+Fid*
+getfid(int fid)
+{
+ int i, freefid;
+
+ freefid = -1;
+ for(i = 0; i < Nfid; i++){
+ if(freefid < 0 && fids[i].file < 0)
+ freefid = i;
+ if(fids[i].fid == fid)
+ return &fids[i];
+ }
+ if(freefid >= 0){
+ fids[freefid].fid = fid;
+ return &fids[freefid];
+ }
+ return nil;
+}
+
+int
+fsstat(int fd, Fid *fid, Fcall *f)
+{
+ Dir d;
+ uchar statbuf[256];
+
+ memset(&d, 0, sizeof(d));
+ d.name = fstab[fid->file].name;
+ d.uid = user;
+ d.gid = user;
+ d.muid = user;
+ d.qid = fstab[fid->file].qid;
+ d.mode = fstab[fid->file].perm;
+ d.atime = d.mtime = time(0);
+ f->stat = statbuf;
+ f->nstat = convD2M(&d, statbuf, sizeof statbuf);
+ return fsreply(fd, f);
+}
+
+int
+fsread(int fd, Fid *fid, Fcall *f)
+{
+ Dir d;
+ uchar buf[256];
+ Request *rp;
+
+ switch(fid->file){
+ default:
+ return -1;
+ case Qdir:
+ if(f->offset == 0 && f->count >0){
+ memset(&d, 0, sizeof(d));
+ d.name = fstab[Qcpunote].name;
+ d.uid = user;
+ d.gid = user;
+ d.muid = user;
+ d.qid = fstab[Qcpunote].qid;
+ d.mode = fstab[Qcpunote].perm;
+ d.atime = d.mtime = time(0);
+ f->count = convD2M(&d, buf, sizeof buf);
+ f->data = (char*)buf;
+ } else
+ f->count = 0;
+ return fsreply(fd, f);
+ case Qcpunote:
+ rp = mallocz(sizeof(*rp), 1);
+ if(rp == nil)
+ return -1;
+ rp->f = *f;
+ lock(&nfs);
+ if(nfs.rfirst == nil)
+ nfs.rfirst = rp;
+ else
+ nfs.rlast->next = rp;
+ nfs.rlast = rp;
+ unlock(&nfs);
+ return kick(fd);;
+ }
+}
+
+char Eperm[] = "permission denied";
+char Enofile[] = "out of files";
+char Enotdir[] = "not a directory";
+
+void
+notefs(int fd)
+{
+ uchar buf[IOHDRSZ+Maxfdata];
+ int i, j, n;
+ char err[ERRMAX];
+ Fcall f;
+ Fid *fid, *nfid;
+ int doreply;
+
+ rfork(RFNOTEG);
+ fmtinstall('F', fcallconv);
+
+ for(n = 0; n < Nfid; n++)
+ fids[n].file = -1;
+
+ for(;;){
+ n = read9pmsg(fd, buf, sizeof(buf));
+ if(n <= 0){
+ if(dbg)
+ fprint(2, "read9pmsg(%d) returns %d: %r\n", fd, n);
+ break;
+ }
+ if(convM2S(buf, n, &f) < 0)
+ break;
+ if(dbg)
+ fprint(2, "->%F\n", &f);
+ doreply = 1;
+ fid = getfid(f.fid);
+ if(fid == nil){
+nofids:
+ f.type = Rerror;
+ f.ename = Enofile;
+ fsreply(fd, &f);
+ continue;
+ }
+ switch(f.type++){
+ default:
+ f.type = Rerror;
+ f.ename = "unknown type";
+ break;
+ case Tflush:
+ flushreq(f.oldtag);
+ break;
+ case Tversion:
+ if(f.msize > IOHDRSZ+Maxfdata)
+ f.msize = IOHDRSZ+Maxfdata;
+ break;
+ case Tauth:
+ f.type = Rerror;
+ f.ename = "cpu: authentication not required";
+ break;
+ case Tattach:
+ f.qid = fstab[Qdir].qid;
+ fid->file = Qdir;
+ break;
+ case Twalk:
+ nfid = nil;
+ if(f.newfid != f.fid){
+ nfid = getfid(f.newfid);
+ if(nfid == nil)
+ goto nofids;
+ nfid->file = fid->file;
+ fid = nfid;
+ }
+
+ f.ename = nil;
+ for(i=0; i<f.nwname; i++){
+ if(i > MAXWELEM){
+ f.type = Rerror;
+ f.ename = "too many name elements";
+ break;
+ }
+ if(fid->file != Qdir){
+ f.type = Rerror;
+ f.ename = Enotdir;
+ break;
+ }
+ if(strcmp(f.wname[i], "cpunote") == 0){
+ fid->file = Qcpunote;
+ f.wqid[i] = fstab[Qcpunote].qid;
+ continue;
+ }
+ f.type = Rerror;
+ f.ename = err;
+ strcpy(err, "cpu: file \"");
+ for(j=0; j<=i; j++){
+ if(strlen(err)+1+strlen(f.wname[j])+32 > sizeof err)
+ break;
+ if(j != 0)
+ strcat(err, "/");
+ strcat(err, f.wname[j]);
+ }
+ strcat(err, "\" does not exist");
+ break;
+ }
+ if(nfid != nil && (f.ename != nil || i < f.nwname))
+ nfid ->file = -1;
+ if(f.type != Rerror)
+ f.nwqid = i;
+ break;
+ case Topen:
+ if(f.mode != OREAD){
+ f.type = Rerror;
+ f.ename = Eperm;
+ }
+ f.qid = fstab[fid->file].qid;
+ break;
+ case Tcreate:
+ f.type = Rerror;
+ f.ename = Eperm;
+ break;
+ case Tread:
+ if(fsread(fd, fid, &f) < 0)
+ goto err;
+ doreply = 0;
+ break;
+ case Twrite:
+ f.type = Rerror;
+ f.ename = Eperm;
+ break;
+ case Tclunk:
+ fid->file = -1;
+ break;
+ case Tremove:
+ f.type = Rerror;
+ f.ename = Eperm;
+ break;
+ case Tstat:
+ if(fsstat(fd, fid, &f) < 0)
+ goto err;
+ doreply = 0;
+ break;
+ case Twstat:
+ f.type = Rerror;
+ f.ename = Eperm;
+ break;
+ }
+ if(doreply)
+ if(fsreply(fd, &f) < 0)
+ break;
+ }
+err:
+ if(dbg)
+ fprint(2, "notefs exiting: %r\n");
+ close(fd);
+}
+
+char notebuf[ERRMAX];
+
+void
+catcher(void*, char *text)
+{
+ int n;
+
+ n = strlen(text);
+ if(n >= sizeof(notebuf))
+ n = sizeof(notebuf)-1;
+ memmove(notebuf, text, n);
+ notebuf[n] = '\0';
+ noted(NCONT);
+}
+
+/*
+ * mount in /dev a note file for the remote side to read.
+ */
+void
+lclnoteproc(int netfd)
+{
+ int exportfspid;
+ Waitmsg *w;
+ Note *np;
+ int pfd[2];
+
+ if(pipe(pfd) < 0){
+ fprint(2, "cpu: can't start note proc: pipe: %r\n");
+ return;
+ }
+
+ /* new proc mounts and returns to start exportfs */
+ switch(exportfspid = rfork(RFPROC|RFNAMEG|RFFDG|RFMEM)){
+ case -1:
+ fprint(2, "cpu: can't start note proc: rfork: %r\n");
+ return;
+ case 0:
+ close(pfd[0]);
+ if(mount(pfd[1], -1, "/dev", MBEFORE, "") < 0)
+ fprint(2, "cpu: can't mount note proc: %r\n");
+ close(pfd[1]);
+ return;
+ }
+
+ close(netfd);
+ close(pfd[1]);
+
+ /* new proc listens for note file system rpc's */
+ switch(rfork(RFPROC|RFNAMEG|RFMEM)){
+ case -1:
+ fprint(2, "cpu: can't start note proc: rfork1: %r\n");
+ _exits(0);
+ case 0:
+ notefs(pfd[0]);
+ _exits(0);
+ }
+
+ /* original proc waits for notes */
+ notify(catcher);
+ w = nil;
+ for(;;) {
+ *notebuf = 0;
+ free(w);
+ w = wait();
+ if(w == nil) {
+ if(*notebuf == 0)
+ break;
+ np = mallocz(sizeof(Note), 1);
+ if(np != nil){
+ strcpy(np->msg, notebuf);
+ lock(&nfs);
+ if(nfs.nfirst == nil)
+ nfs.nfirst = np;
+ else
+ nfs.nlast->next = np;
+ nfs.nlast = np;
+ unlock(&nfs);
+ kick(pfd[0]);
+ }
+ unlock(&nfs);
+ } else if(w->pid == exportfspid)
+ break;
+ }
+
+ if(w == nil)
+ exits(nil);
+ exits(w->msg);
+}