support/nfs/nfssvc.c

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