utils/nfsd/nfssvc.c

   1 /*
   2  * utils/nfsd/nfssvc.c
   3  *
   4  * Run an NFS daemon.
   5  *
   6  * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
   7  */
   8
   9 #ifdef HAVE_CONFIG_H
  10 #include <config.h>
  11 #endif
  12
  13 #include <sys/socket.h>
  14 #include <netinet/in.h>
  15 #include <arpa/inet.h>
  16 #include <unistd.h>
  17 #include <fcntl.h>
  18 #include <errno.h>
  19
  20 #include "nfslib.h"
  21 #include "xlog.h"
  22
  23 #define NFSD_PORTS_FILE     "/proc/fs/nfsd/portlist"
  24 #define NFSD_VERS_FILE    "/proc/fs/nfsd/versions"
  25 #define NFSD_THREAD_FILE  "/proc/fs/nfsd/threads"
  26
  27 static void
  28 nfssvc_setfds(int port, unsigned int ctlbits, char *haddr)
  29 {
  30         int fd, n, on=1;
  31         char buf[BUFSIZ];
  32         int udpfd = -1, tcpfd = -1;
  33         struct sockaddr_in sin;
  34
  35         fd = open(NFSD_PORTS_FILE, O_RDONLY);
  36         if (fd < 0)
  37                 return;
  38         n = read(fd, buf, BUFSIZ);
  39         close(fd);
  40         if (n != 0)
  41                 return;
  42         /* there are no ports currently open, so it is safe to
  43          * try to open some and pass them through.
  44          * Note: If the user explicitly asked for 'udp', then
  45          * we should probably check if that is open, and should
  46          * open it if not.  However we don't yet.  All sockets
  47          * have to be opened when the first daemon is started.
  48          */
  49         fd = open(NFSD_PORTS_FILE, O_WRONLY);
  50         if (fd < 0)
  51                 return;
  52         sin.sin_family = AF_INET;
  53         sin.sin_port   = htons(port);
  54         sin.sin_addr.s_addr =  inet_addr(haddr);
  55
  56         if (NFSCTL_UDPISSET(ctlbits)) {
  57                 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
  58                 if (udpfd < 0) {
  59                         xlog(L_ERROR, "unable to create UDP socket: "
  60                                 "errno %d (%m)", errno);
  61                         exit(1);
  62                 }
  63                 if (bind(udpfd, (struct  sockaddr  *)&sin, sizeof(sin)) < 0){
  64                         xlog(L_ERROR, "unable to bind UDP socket: "
  65                                 "errno %d (%m)", errno);
  66                         exit(1);
  67                 }
  68         }
  69
  70         if (NFSCTL_TCPISSET(ctlbits)) {
  71                 tcpfd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
  72                 if (tcpfd < 0) {
  73                         xlog(L_ERROR, "unable to create TCP socket: "
  74                                 "errno %d (%m)", errno);
  75                         exit(1);
  76                 }
  77                 if (setsockopt(tcpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0) {
  78                         xlog(L_ERROR, "unable to set SO_REUSEADDR: "
  79                                 "errno %d (%m)", errno);
  80                         exit(1);
  81                 }
  82                 if (bind(tcpfd, (struct  sockaddr  *)&sin, sizeof(sin)) < 0){
  83                         xlog(L_ERROR, "unable to bind TCP socket: "
  84                                 "errno %d (%m)", errno);
  85                         exit(1);
  86                 }
  87                 if (listen(tcpfd, 64) < 0){
  88                         xlog(L_ERROR, "unable to create listening socket: "
  89                                 "errno %d (%m)", errno);
  90                         exit(1);
  91                 }
  92         }
  93         if (udpfd >= 0) {
  94                 snprintf(buf, BUFSIZ,"%d\n", udpfd);
  95                 if (write(fd, buf, strlen(buf)) != strlen(buf)) {
  96                         xlog(L_ERROR,
  97                                "writing fds to kernel failed: errno %d (%m)",
  98                                errno);
  99                 }
 100                 close(fd);
 101                 fd = -1;
 102         }
 103         if (tcpfd >= 0) {
 104                 if (fd < 0)
 105                         fd = open(NFSD_PORTS_FILE, O_WRONLY);
 106                 snprintf(buf, BUFSIZ,"%d\n", tcpfd);
 107                 if (write(fd, buf, strlen(buf)) != strlen(buf)) {
 108                         xlog(L_ERROR,
 109                                "writing fds to kernel failed: errno %d (%m)",
 110                                errno);
 111                 }
 112         }
 113         close(fd);
 114
 115         return;
 116 }
 117 static void
 118 nfssvc_versbits(unsigned int ctlbits, int minorvers4)
 119 {
 120         int fd, n, off;
 121         char buf[BUFSIZ], *ptr;
 122
 123         ptr = buf;
 124         off = 0;
 125         fd = open(NFSD_VERS_FILE, O_WRONLY);
 126         if (fd < 0)
 127                 return;
 128
 129         for (n = NFSD_MINVERS; n <= NFSD_MAXVERS; n++) {
 130                 if (NFSCTL_VERISSET(ctlbits, n))
 131                     off += snprintf(ptr+off, BUFSIZ - off, "+%d ", n);
 132                 else
 133                     off += snprintf(ptr+off, BUFSIZ - off, "-%d ", n);
 134         }
 135         n = minorvers4 >= 0 ? minorvers4 : -minorvers4;
 136         if (n >= NFSD_MINMINORVERS4 && n <= NFSD_MAXMINORVERS4)
 137                     off += snprintf(ptr+off, BUFSIZ - off, "%c4.%d",
 138                                     minorvers4 > 0 ? '+' : '-',
 139                                     n);
 140         xlog(D_GENERAL, "Writing version string to kernel: %s", buf);
 141         snprintf(ptr+off, BUFSIZ - off, "\n");
 142         if (write(fd, buf, strlen(buf)) != strlen(buf))
 143                 xlog(L_ERROR, "Setting version failed: errno %d (%m)", errno);
 144
 145         close(fd);
 146
 147         return;
 148 }
 149 int
 150 nfssvc(int port, int nrservs, unsigned int versbits, int minorvers4,
 151         unsigned protobits, char *haddr)
 152 {
 153         struct nfsctl_arg       arg;
 154         int fd;
 155
 156         /* Note: must set versions before fds so that
 157          * the ports get registered with portmap against correct
 158          * versions
 159          */
 160         nfssvc_versbits(versbits, minorvers4);
 161         nfssvc_setfds(port, protobits, haddr);
 162
 163         fd = open(NFSD_THREAD_FILE, O_WRONLY);
 164         if (fd < 0)
 165                 fd = open("/proc/fs/nfs/threads", O_WRONLY);
 166         if (fd >= 0) {
 167                 /* 2.5+ kernel with nfsd filesystem mounted.
 168                  * Just write the number in.
 169                  * Cannot handle port number yet, but does anyone care?
 170                  */
 171                 char buf[20];
 172                 int n;
 173                 snprintf(buf, 20,"%d\n", nrservs);
 174                 n = write(fd, buf, strlen(buf));
 175                 close(fd);
 176                 if (n != strlen(buf))
 177                         return -1;
 178                 else
 179                         return 0;
 180         }
 181
 182         arg.ca_version = NFSCTL_VERSION;
 183         arg.ca_svc.svc_nthreads = nrservs;
 184         arg.ca_svc.svc_port = port;
 185         return nfsctl(NFSCTL_SVC, &arg, NULL);
 186 }