]> git.decadent.org.uk Git - nfs-utils.git/blobdiff - utils/exportfs/exportfs.c
Merge branch 'sid'
[nfs-utils.git] / utils / exportfs / exportfs.c
index 83d00a0637a9ab819c406c202ba1f1dfa5d5b3d1..9f7954130ee2adf9579f933ec44134d25ed141da 100644 (file)
 #include <config.h>
 #endif
 
+#include <sys/types.h>
+#include <sys/stat.h>
 #include <sys/vfs.h>
 #include <sys/stat.h>
+#include <sys/file.h>
 #include <unistd.h>
+#include <stdbool.h>
 #include <stdlib.h>
 #include <string.h>
 #include <stdarg.h>
 #include <getopt.h>
+#include <fcntl.h>
 #include <netdb.h>
 #include <errno.h>
-#include "xmalloc.h"
+#include <dirent.h>
+
+#include "sockaddr.h"
 #include "misc.h"
 #include "nfslib.h"
 #include "exportfs.h"
-#include "xmalloc.h"
 #include "xlog.h"
 
 static void    export_all(int verbose);
@@ -34,13 +40,51 @@ static void unexportfs(char *arg, int verbose);
 static void    exports_update(int verbose);
 static void    dump(int verbose);
 static void    error(nfs_export *exp, int err);
-static void    usage(void);
+static void    usage(const char *progname, int n);
 static void    validate_export(nfs_export *exp);
+static int     matchhostname(const char *hostname1, const char *hostname2);
+static void    export_d_read(const char *dname);
+static void grab_lockfile(void);
+static void release_lockfile(void);
+
+static const char *lockfile = EXP_LOCKFILE;
+static int _lockfd = -1;
+
+/*
+ * If we aren't careful, changes made by exportfs can be lost
+ * when multiple exports process run at once:
+ *
+ *     exportfs process 1      exportfs process 2
+ *     ------------------------------------------
+ *     reads etab version A    reads etab version A
+ *     adds new export B       adds new export C
+ *     writes A+B              writes A+C
+ *
+ * The locking in support/export/xtab.c will prevent mountd from
+ * seeing a partially written version of etab, and will prevent 
+ * the two writers above from writing simultaneously and
+ * corrupting etab, but to prevent problems like the above we
+ * need these additional lockfile() routines.
+ */
+static void 
+grab_lockfile()
+{
+       _lockfd = open(lockfile, O_CREAT|O_RDWR, 0666);
+       if (_lockfd != -1) 
+               lockf(_lockfd, F_LOCK, 0);
+}
+static void 
+release_lockfile()
+{
+       if (_lockfd != -1)
+               lockf(_lockfd, F_ULOCK, 0);
+}
 
 int
 main(int argc, char **argv)
 {
        char    *options = NULL;
+       char    *progname = NULL;
        int     f_export = 1;
        int     f_all = 0;
        int     f_verbose = 0;
@@ -50,15 +94,28 @@ main(int argc, char **argv)
        int     new_cache = 0;
        int     force_flush = 0;
 
-       xlog_open("exportfs");
+       if ((progname = strrchr(argv[0], '/')) != NULL)
+               progname++;
+       else
+               progname = argv[0];
+
+       xlog_open(progname);
+       xlog_stderr(1);
+       xlog_syslog(0);
 
        export_errno = 0;
 
-       while ((c = getopt(argc, argv, "aio:ruvf")) != EOF) {
+       while ((c = getopt(argc, argv, "afhio:ruv")) != EOF) {
                switch(c) {
                case 'a':
                        f_all = 1;
                        break;
+               case 'f':
+                       force_flush = 1;
+                       break;
+               case 'h':
+                       usage(progname, 0);
+                       break;
                case 'i':
                        f_ignore = 1;
                        break;
@@ -75,25 +132,22 @@ main(int argc, char **argv)
                case 'v':
                        f_verbose = 1;
                        break;
-               case 'f':
-                       force_flush = 1;
-                       break;
                default:
-                       usage();
+                       usage(progname, 1);
                        break;
                }
        }
 
        if (optind != argc && f_all) {
-               fprintf(stderr,"exportfs: extra arguments are not permitted with -a or -r.\n");
+               xlog(L_ERROR, "extra arguments are not permitted with -a or -r");
                return 1;
        }
        if (f_ignore && (f_all || ! f_export)) {
-               fprintf(stderr,"exportfs: -i not meaningful with -a, -r or -u.\n");
+               xlog(L_ERROR, "-i not meaningful with -a, -r or -u");
                return 1;
        }
        if (f_reexport && ! f_export) {
-               fprintf(stderr, "exportfs: -r and -u are incompatible.\n");
+               xlog(L_ERROR, "-r and -u are incompatible");
                return 1;
        }
        new_cache = check_new_cache();
@@ -102,8 +156,10 @@ main(int argc, char **argv)
                        if (new_cache)
                                cache_flush(1);
                        else {
-                               fprintf(stderr, "exportfs: -f: only available with new cache controls: mount /proc/fs/nfsd first\n");
-                               exit(1);
+                               xlog(L_ERROR, "-f is available only "
+                                       "with new cache controls. "
+                                       "Mount /proc/fs/nfsd first");
+                               return 1;
                        }
                        return 0;
                } else {
@@ -112,8 +168,17 @@ main(int argc, char **argv)
                        return 0;
                }
        }
-       if (f_export && ! f_ignore)
+
+       /*
+        * Serialize things as best we can
+        */
+       grab_lockfile();
+       atexit(release_lockfile);
+
+       if (f_export && ! f_ignore) {
                export_read(_PATH_EXPORTS);
+               export_d_read(_PATH_EXPORTS_D);
+       }
        if (f_export) {
                if (f_all)
                        export_all(f_verbose);
@@ -231,8 +296,8 @@ static void
 exportfs(char *arg, char *options, int verbose)
 {
        struct exportent *eep;
-       nfs_export      *exp;
-       struct hostent  *hp = NULL;
+       nfs_export      *exp = NULL;
+       struct addrinfo *ai = NULL;
        char            *path;
        char            *hname = arg;
        int             htype;
@@ -241,36 +306,25 @@ exportfs(char *arg, char *options, int verbose)
                *path++ = '\0';
 
        if (!path || *path != '/') {
-               fprintf(stderr, "Invalid exporting option: %s\n", arg);
+               xlog(L_ERROR, "Invalid exporting option: %s", arg);
                return;
        }
 
-       if ((htype = client_gettype(hname)) == MCL_FQDN &&
-           (hp = gethostbyname(hname)) != NULL) {
-               struct hostent *hp2 = hostent_dup (hp);
-               hp = gethostbyaddr(hp2->h_addr, hp2->h_length,
-                                  hp2->h_addrtype);
-               if (hp) {
-                       free(hp2);
-                       hp = hostent_dup(hp);
-               } else
-                       hp = hp2;
-               exp = export_find(hp, path);
-               hname = hp->h_name;
-       } else {
+       if ((htype = client_gettype(hname)) == MCL_FQDN) {
+               ai = host_addrinfo(hname);
+               if (ai != NULL) {
+                       exp = export_find(ai, path);
+                       hname = ai->ai_canonname;
+               }
+       } else
                exp = export_lookup(hname, path, 0);
-       }
 
        if (!exp) {
                if (!(eep = mkexportent(hname, path, options)) ||
-                   !(exp = export_create(eep, 0))) {
-                       if (hp) free (hp);
-                       return;
-               }
-       } else if (!updateexportent(&exp->m_export, options)) {
-               if (hp) free (hp);
-               return;
-       }
+                   !(exp = export_create(eep, 0)))
+                       goto out;
+       } else if (!updateexportent(&exp->m_export, options))
+               goto out;
 
        if (verbose)
                printf("exporting %s:%s\n", exp->m_client->m_hostname, 
@@ -280,7 +334,9 @@ exportfs(char *arg, char *options, int verbose)
        exp->m_changed = 1;
        exp->m_warned = 0;
        validate_export(exp);
-       if (hp) free (hp);
+
+out:
+       freeaddrinfo(ai);
 }
 
 static void
@@ -296,8 +352,7 @@ unexportfs(char *arg, int verbose)
                *path++ = '\0';
 
        if (!path || *path != '/') {
-               fprintf(stderr, "Invalid unexporting option: %s\n",
-                       arg);
+               xlog(L_ERROR, "Invalid unexporting option: %s", arg);
                return;
        }
 
@@ -392,14 +447,12 @@ validate_export(nfs_export *exp)
        int fs_has_fsid = 0;
 
        if (stat(path, &stb) < 0) {
-               fprintf(stderr, "exportfs: Warning: %s does not exist\n",
-                       path);
+               xlog(L_ERROR, "Failed to stat %s: %m", path);
                return;
        }
        if (!S_ISDIR(stb.st_mode) && !S_ISREG(stb.st_mode)) {
-               fprintf(stderr, "exportfs: Warning: %s is neither "
-                       "a directory nor a file.\n"
-                       "     remote access will fail\n", path);
+               xlog(L_ERROR, "%s is neither a directory nor a file. "
+                       "Remote access will fail", path);
                return;
        }
        if (!can_test())
@@ -412,24 +465,161 @@ validate_export(nfs_export *exp)
        if ((exp->m_export.e_flags & NFSEXP_FSID) || exp->m_export.e_uuid ||
            fs_has_fsid) {
                if ( !test_export(path, 1)) {
-                       fprintf(stderr, "exportfs: Warning: %s does not "
-                               "support NFS export.\n",
-                               path);
+                       xlog(L_ERROR, "%s does not support NFS export", path);
                        return;
                }
        } else if ( ! test_export(path, 0)) {
                if (test_export(path, 1))
-                       fprintf(stderr, "exportfs: Warning: %s requires fsid= "
-                               "for NFS export\n", path);
+                       xlog(L_ERROR, "%s requires fsid= for NFS export", path);
                else
-                       fprintf(stderr, "exportfs: Warning: %s does not "
-                               "support NFS export.\n",
-                               path);
+                       xlog(L_ERROR, "%s does not support NFS export", path);
                return;
 
        }
 }
 
+static _Bool
+is_hostname(const char *sp)
+{
+       if (*sp == '\0' || *sp == '@')
+               return false;
+
+       for (; *sp != '\0'; sp++) {
+               if (*sp == '*' || *sp == '?' || *sp == '[' || *sp == '/')
+                       return false;
+               if (*sp == '\\' && sp[1] != '\0')
+                       sp++;
+       }
+
+       return true;
+}
+
+/*
+ * Take care to perform an explicit reverse lookup on presentation
+ * addresses.  Otherwise we don't get a real canonical name or a
+ * complete list of addresses.
+ */
+static struct addrinfo *
+address_list(const char *hostname)
+{
+       struct addrinfo *ai;
+       char *cname;
+
+       ai = host_pton(hostname);
+       if (ai != NULL) {
+               /* @hostname was a presentation address */
+               cname = host_canonname(ai->ai_addr);
+               freeaddrinfo(ai);
+               if (cname != NULL)
+                       goto out;
+       }
+       /* @hostname was a hostname or had no reverse mapping */
+       cname = strdup(hostname);
+       if (cname == NULL)
+               return NULL;
+
+out:
+       ai = host_addrinfo(cname);
+       free(cname);
+       return ai;
+}
+
+static int
+matchhostname(const char *hostname1, const char *hostname2)
+{
+       struct addrinfo *results1 = NULL, *results2 = NULL;
+       struct addrinfo *ai1, *ai2;
+       int result = 0;
+
+       if (strcasecmp(hostname1, hostname2) == 0)
+               return 1;
+
+       /*
+        * Don't pass export wildcards or netgroup names to DNS
+        */
+       if (!is_hostname(hostname1) || !is_hostname(hostname2))
+               return 0;
+
+       results1 = address_list(hostname1);
+       if (results1 == NULL)
+               goto out;
+       results2 = address_list(hostname2);
+       if (results2 == NULL)
+               goto out;
+
+       if (strcasecmp(results1->ai_canonname, results2->ai_canonname) == 0) {
+               result = 1;
+               goto out;
+       }
+
+       for (ai1 = results1; ai1 != NULL; ai1 = ai1->ai_next)
+               for (ai2 = results2; ai2 != NULL; ai2 = ai2->ai_next)
+                       if (nfs_compare_sockaddr(ai1->ai_addr, ai2->ai_addr)) {
+                               result = 1;
+                               break;
+                       }
+
+out:
+       freeaddrinfo(results1);
+       freeaddrinfo(results2);
+       return result;
+}
+
+/* Based on mnt_table_parse_dir() in
+   util-linux-ng/shlibs/mount/src/tab_parse.c */
+static void
+export_d_read(const char *dname)
+{
+       int n = 0, i;
+       struct dirent **namelist = NULL;
+
+
+       n = scandir(dname, &namelist, NULL, versionsort);
+       if (n < 0) {
+               if (errno == ENOENT)
+                       /* Silently return */
+                       return;
+               xlog(L_NOTICE, "scandir %s: %s", dname, strerror(errno));
+       } else if (n == 0)
+               return;
+
+       for (i = 0; i < n; i++) {
+               struct dirent *d = namelist[i];
+               size_t namesz;
+               char fname[PATH_MAX + 1];
+               int fname_len;
+
+
+               if (d->d_type != DT_UNKNOWN 
+                   && d->d_type != DT_REG
+                   && d->d_type != DT_LNK)
+                       continue;
+               if (*d->d_name == '.')
+                       continue;
+
+#define _EXT_EXPORT_SIZ   (sizeof(_EXT_EXPORT) - 1)
+               namesz = strlen(d->d_name);
+               if (!namesz 
+                   || namesz < _EXT_EXPORT_SIZ + 1
+                   || strcmp(d->d_name + (namesz - _EXT_EXPORT_SIZ),
+                             _EXT_EXPORT))
+                       continue;
+
+               fname_len = snprintf(fname, PATH_MAX +1, "%s/%s", dname, d->d_name);
+               if (fname_len > PATH_MAX) {
+                       xlog(L_WARNING, "Too long file name: %s in %s", d->d_name, dname);
+                       continue;
+               }
+
+               export_read(fname);
+       }
+               
+       for (i = 0; i < n; i++)
+               free(namelist[i]);
+       free(namelist);
+
+       return;
+}
 
 static char
 dumpopt(char c, char *fmt, ...)
@@ -531,13 +721,13 @@ dump(int verbose)
 static void
 error(nfs_export *exp, int err)
 {
-       fprintf(stderr, "%s:%s: %s\n", exp->m_client->m_hostname, 
+       xlog(L_ERROR, "%s:%s: %s", exp->m_client->m_hostname,
                exp->m_export.e_path, strerror(err));
 }
 
 static void
-usage(void)
+usage(const char *progname, int n)
 {
-       fprintf(stderr, "usage: exportfs [-aruv] [host:/path]\n");
-       exit(1);
+       fprintf(stderr, "usage: %s [-afhioruv] [host:/path]\n", progname);
+       exit(n);
 }