diff options
| -rw-r--r-- | usr.sbin/nfsd/nfsd.c | 119 |
1 files changed, 110 insertions, 9 deletions
diff --git a/usr.sbin/nfsd/nfsd.c b/usr.sbin/nfsd/nfsd.c index 364045d..6e607f7 100644 --- a/usr.sbin/nfsd/nfsd.c +++ b/usr.sbin/nfsd/nfsd.c @@ -51,6 +51,9 @@ static const char rcsid[] = #include <sys/fcntl.h> #include <sys/linker.h> #include <sys/module.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <sys/ucred.h> #include <rpc/rpc.h> #include <rpc/pmap_clnt.h> @@ -79,6 +82,7 @@ int debug = 0; #endif #define NFSD_STABLERESTART "/var/db/nfs-stablerestart" +#define NFSD_STABLEBACKUP "/var/db/nfs-stablerestart.bak" #define MAXNFSDCNT 256 #define DEFNFSDCNT 4 pid_t children[MAXNFSDCNT]; /* PIDs of children */ @@ -86,6 +90,8 @@ int nfsdcnt; /* number of children */ int new_syscall; int run_v4server = 0; /* Force running of nfsv4 server */ int nfssvc_nfsd; /* Set to correct NFSSVC_xxx flag */ +int stablefd = -1; /* Fd for the stable restart file */ +int backupfd; /* Fd for the backup stable restart file */ void cleanup(int); void child_cleanup(int); @@ -98,6 +104,9 @@ int setbindhost(struct addrinfo **ia, const char *bindhost, void start_server(int); void unregistration(void); void usage(void); +void open_stable(int *, int *); +void copy_stable(int, int); +void backup_stable(int); /* * Nfs server daemon mostly just a user context for nfssvc() @@ -136,7 +145,7 @@ main(int argc, char **argv) int tcp6sock, ip6flag, tcpflag, tcpsock; int udpflag, ecode, error, s, srvcnt; int bindhostc, bindanyflag, rpcbreg, rpcbregcnt; - int stablefd, nfssvc_addsock; + int nfssvc_addsock; char **bindhost = NULL; pid_t pid; @@ -346,6 +355,7 @@ main(int argc, char **argv) } (void)signal(SIGSYS, nonfs); (void)signal(SIGCHLD, reapchild); + (void)signal(SIGUSR2, backup_stable); openlog("nfsd", LOG_PID, LOG_DAEMON); @@ -355,22 +365,21 @@ main(int argc, char **argv) * regular nfssvc() call to service NFS requests. * (This way the file remains open until the last nfsd is killed * off.) - * Note that this file is not created by this daemon and can - * only be relocated by recompiling the daemon, in order to - * minimize accidentally starting up with the wrong file. - * If should be created as an empty file Read and Write for - * root before the first time you run NFS v4 and should never - * be re-initialized if at all possible. It should live on a + * It and the backup copy will be created as empty files + * the first time this nfsd is started and should never be + * deleted/replaced if at all possible. It should live on a * local, non-volatile storage device that does not do hardware * level write-back caching. (See SCSI doc for more information * on how to prevent write-back caching on SCSI disks.) */ if (run_v4server > 0) { - stablefd = open(NFSD_STABLERESTART, O_RDWR, 0); + open_stable(&stablefd, &backupfd); if (stablefd < 0) { syslog(LOG_ERR, "Can't open %s\n", NFSD_STABLERESTART); exit(1); } + /* This system call will fail for old kernels, but that's ok. */ + nfssvc(NFSSVC_BACKUPSTABLE, NULL); if (nfssvc(NFSSVC_STABLERESTART, (caddr_t)&stablefd) < 0) { syslog(LOG_ERR, "Can't read stable storage file\n"); exit(1); @@ -739,9 +748,9 @@ main(int argc, char **argv) if (select(maxsock + 1, &ready, NULL, NULL, NULL) < 1) { error = errno; - syslog(LOG_ERR, "select failed: %m"); if (error == EINTR) continue; + syslog(LOG_ERR, "select failed: %m"); nfsd_exit(1); } } @@ -973,3 +982,95 @@ start_server(int master) else exit(status); } + +/* + * Open the stable restart file and return the file descriptor for it. + */ +void +open_stable(int *stable_fdp, int *backup_fdp) +{ + int stable_fd, backup_fd = -1, ret; + struct stat st, backup_st; + + /* Open and stat the stable restart file. */ + stable_fd = open(NFSD_STABLERESTART, O_RDWR, 0); + if (stable_fd < 0) + stable_fd = open(NFSD_STABLERESTART, O_RDWR | O_CREAT, 0600); + if (stable_fd >= 0) { + ret = fstat(stable_fd, &st); + if (ret < 0) { + close(stable_fd); + stable_fd = -1; + } + } + + /* Open and stat the backup stable restart file. */ + if (stable_fd >= 0) { + backup_fd = open(NFSD_STABLEBACKUP, O_RDWR, 0); + if (backup_fd < 0) + backup_fd = open(NFSD_STABLEBACKUP, O_RDWR | O_CREAT, + 0600); + if (backup_fd >= 0) { + ret = fstat(backup_fd, &backup_st); + if (ret < 0) { + close(backup_fd); + backup_fd = -1; + } + } + if (backup_fd < 0) { + close(stable_fd); + stable_fd = -1; + } + } + + *stable_fdp = stable_fd; + *backup_fdp = backup_fd; + if (stable_fd < 0) + return; + + /* Sync up the 2 files, as required. */ + if (st.st_size > 0) + copy_stable(stable_fd, backup_fd); + else if (backup_st.st_size > 0) + copy_stable(backup_fd, stable_fd); +} + +/* + * Copy the stable restart file to the backup or vice versa. + */ +void +copy_stable(int from_fd, int to_fd) +{ + int cnt, ret; + static char buf[1024]; + + ret = lseek(from_fd, (off_t)0, SEEK_SET); + if (ret >= 0) + ret = lseek(to_fd, (off_t)0, SEEK_SET); + if (ret >= 0) + ret = ftruncate(to_fd, (off_t)0); + if (ret >= 0) + do { + cnt = read(from_fd, buf, 1024); + if (cnt > 0) + ret = write(to_fd, buf, cnt); + else if (cnt < 0) + ret = cnt; + } while (cnt > 0 && ret >= 0); + if (ret >= 0) + ret = fsync(to_fd); + if (ret < 0) + syslog(LOG_ERR, "stable restart copy failure: %m"); +} + +/* + * Back up the stable restart file when indicated by the kernel. + */ +void +backup_stable(__unused int signo) +{ + + if (stablefd >= 0) + copy_stable(stablefd, backupfd); +} + |
