]> git.decadent.org.uk Git - nfs-utils.git/blobdiff - utils/mountd/cache.c
nfsidmap: Added Error Logging
[nfs-utils.git] / utils / mountd / cache.c
index 15100d499e91edb442130d0afc1123108ce88e5a..d2ae4563d31a1ebe855e34053ac99cda6c56cc09 100644 (file)
@@ -14,6 +14,7 @@
 #include <sys/types.h>
 #include <sys/select.h>
 #include <sys/stat.h>
+#include <sys/vfs.h>
 #include <time.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include "blkid/blkid.h"
 #endif
 
+/*
+ * Invoked by RPC service loop
+ */
+void   cache_set_fds(fd_set *fdset);
+int    cache_process_req(fd_set *readfds);
 
 enum nfsd_fsid {
        FSID_DEV = 0,
@@ -56,13 +62,15 @@ enum nfsd_fsid {
  * Record is terminated with newline.
  *
  */
-int cache_export_ent(char *domain, struct exportent *exp, char *p);
+static int cache_export_ent(char *domain, struct exportent *exp, char *p);
 
+#define INITIAL_MANAGED_GROUPS 100
 
 char *lbuf  = NULL;
 int lbuflen = 0;
+extern int use_ipaddr;
 
-void auth_unix_ip(FILE *f)
+static void auth_unix_ip(FILE *f)
 {
        /* requests are
         *  class IP-ADDR
@@ -73,60 +81,82 @@ void auth_unix_ip(FILE *f)
         */
        char *cp;
        char class[20];
-       char ipaddr[20];
-       char *client;
-       struct in_addr addr;
+       char ipaddr[INET6_ADDRSTRLEN];
+       char *client = NULL;
+       struct addrinfo *tmp = NULL;
+       struct addrinfo *ai = NULL;
        if (readline(fileno(f), &lbuf, &lbuflen) != 1)
                return;
 
+       xlog(D_CALL, "auth_unix_ip: inbuf '%s'", lbuf);
+
        cp = lbuf;
 
        if (qword_get(&cp, class, 20) <= 0 ||
            strcmp(class, "nfsd") != 0)
                return;
 
-       if (qword_get(&cp, ipaddr, 20) <= 0)
+       if (qword_get(&cp, ipaddr, sizeof(ipaddr)) <= 0)
                return;
 
-       if (inet_aton(ipaddr, &addr)==0)
+       tmp = host_pton(ipaddr);
+       if (tmp == NULL)
                return;
 
        auth_reload();
 
        /* addr is a valid, interesting address, find the domain name... */
-       client = client_compose(addr);
+       if (!use_ipaddr) {
+               ai = client_resolve(tmp->ai_addr);
+               client = client_compose(ai);
+               freeaddrinfo(ai);
+       }
+       freeaddrinfo(tmp);
 
-       
        qword_print(f, "nfsd");
        qword_print(f, ipaddr);
-       qword_printint(f, time(0)+30*60);
-       if (client)
+       qword_printuint(f, time(0) + DEFAULT_TTL);
+       if (use_ipaddr)
+               qword_print(f, ipaddr);
+       else if (client)
                qword_print(f, *client?client:"DEFAULT");
        qword_eol(f);
+       xlog(D_CALL, "auth_unix_ip: client %p '%s'", client, client?client: "DEFAULT");
 
-       if (client) free(client);
-       
+       free(client);
 }
 
-void auth_unix_gid(FILE *f)
+static void auth_unix_gid(FILE *f)
 {
        /* Request are
         *  uid
         * reply is
         *  uid expiry count list of group ids
         */
-       int uid;
+       uid_t uid;
        struct passwd *pw;
-       gid_t glist[100], *groups = glist;
-       int ngroups = 100;
+       static gid_t *groups = NULL;
+       static int groups_len = 0;
+       gid_t *more_groups;
+       int ngroups;
        int rv, i;
        char *cp;
 
+       if (groups_len == 0) {
+               groups = malloc(sizeof(gid_t) * INITIAL_MANAGED_GROUPS);
+               if (!groups)
+                       return;
+
+               groups_len = INITIAL_MANAGED_GROUPS;
+       }
+
+       ngroups = groups_len;
+
        if (readline(fileno(f), &lbuf, &lbuflen) != 1)
                return;
 
        cp = lbuf;
-       if (qword_get_int(&cp, &uid) != 0)
+       if (qword_get_uint(&cp, &uid) != 0)
                return;
 
        pw = getpwuid(uid);
@@ -134,70 +164,81 @@ void auth_unix_gid(FILE *f)
                rv = -1;
        else {
                rv = getgrouplist(pw->pw_name, pw->pw_gid, groups, &ngroups);
-               if (rv == -1 && ngroups >= 100) {
-                       groups = malloc(sizeof(gid_t)*ngroups);
-                       if (!groups)
+               if (rv == -1 && ngroups >= groups_len) {
+                       more_groups = realloc(groups, sizeof(gid_t)*ngroups);
+                       if (!more_groups)
                                rv = -1;
-                       else
+                       else {
+                               groups = more_groups;
+                               groups_len = ngroups;
                                rv = getgrouplist(pw->pw_name, pw->pw_gid,
                                                  groups, &ngroups);
+                       }
                }
        }
-       qword_printint(f, uid);
-       qword_printint(f, time(0)+30*60);
+       qword_printuint(f, uid);
+       qword_printuint(f, time(0) + DEFAULT_TTL);
        if (rv >= 0) {
-               qword_printint(f, ngroups);
+               qword_printuint(f, ngroups);
                for (i=0; i<ngroups; i++)
-                       qword_printint(f, groups[i]);
-       }
+                       qword_printuint(f, groups[i]);
+       } else
+               qword_printuint(f, 0);
        qword_eol(f);
-       if (groups != glist)
-               free(groups);
 }
 
 #if USE_BLKID
-int get_uuid(char *path, char *uuid, int uuidlen, char *u)
+static const char *get_uuid_blkdev(char *path)
+{
+       /* We set *safe if we know that we need the
+        * fsid from statfs too.
+        */
+       static blkid_cache cache = NULL;
+       struct stat stb;
+       char *devname;
+       blkid_tag_iterate iter;
+       blkid_dev dev;
+       const char *type;
+       const char *val, *uuid = NULL;
+
+       if (cache == NULL)
+               blkid_get_cache(&cache, NULL);
+
+       if (stat(path, &stb) != 0)
+               return NULL;
+       devname = blkid_devno_to_devname(stb.st_dev);
+       if (!devname)
+               return NULL;
+       dev = blkid_get_dev(cache, devname, BLKID_DEV_NORMAL);
+       free(devname);
+       if (!dev)
+               return NULL;
+       iter = blkid_tag_iterate_begin(dev);
+       if (!iter)
+               return NULL;
+       while (blkid_tag_next(iter, &type, &val) == 0) {
+               if (strcmp(type, "UUID") == 0)
+                       uuid = val;
+               if (strcmp(type, "TYPE") == 0 &&
+                   strcmp(val, "btrfs") == 0) {
+                       uuid = NULL;
+                       break;
+               }
+       }
+       blkid_tag_iterate_end(iter);
+       return uuid;
+}
+#else
+#define get_uuid_blkdev(path) (NULL)
+#endif
+
+static int get_uuid(const char *val, int uuidlen, char *u)
 {
        /* extract hex digits from uuidstr and compose a uuid
         * of the given length (max 16), xoring bytes to make
-        * a smaller uuid.  Then compare with uuid
+        * a smaller uuid.
         */
        int i = 0;
-       const char *val;
-
-       if (path) {
-               static blkid_cache cache = NULL;
-               struct stat stb;
-               char *devname;
-               blkid_tag_iterate iter;
-               blkid_dev dev;
-               const char *type;
-               if (cache == NULL)
-                       blkid_get_cache(&cache, NULL);
-
-               blkid_probe_all_new(cache);
-
-               if (stat(path, &stb) != 0)
-                       return 0;
-               devname = blkid_devno_to_devname(stb.st_dev);
-               if (!devname)
-                       return 0;
-               dev = blkid_get_dev(cache, devname, BLKID_DEV_NORMAL);
-               free(devname);
-               if (!dev)
-                       return 0;
-               iter = blkid_tag_iterate_begin(dev);
-               if (!iter)
-                       return 0;
-               while (blkid_tag_next(iter, &type, &val) == 0)
-                       if (strcmp(type, "UUID") == 0)
-                               break;
-               blkid_tag_iterate_end(iter);
-               if (!type)
-                       return 0;
-       } else {
-               val = uuid;
-       }
        
        memset(u, 0, uuidlen);
        for ( ; *val ; val++) {
@@ -220,7 +261,60 @@ int get_uuid(char *path, char *uuid, int uuidlen, char *u)
        }
        return 1;
 }
-#endif
+
+static int uuid_by_path(char *path, int type, int uuidlen, char *uuid)
+{
+       /* get a uuid for the filesystem found at 'path'.
+        * There are several possible ways of generating the
+        * uuids (types).
+        * Type 0 is used for new filehandles, while other types
+        * may be used to interpret old filehandle - to ensure smooth
+        * forward migration.
+        * We return 1 if a uuid was found (and it might be worth 
+        * trying the next type) or 0 if no more uuid types can be
+        * extracted.
+        */
+
+       /* Possible sources of uuid are
+        * - blkid uuid
+        * - statfs64 uuid
+        *
+        * On some filesystems (e.g. vfat) the statfs64 uuid is simply an
+        * encoding of the device that the filesystem is mounted from, so
+        * it we be very bad to use that (as device numbers change).  blkid
+        * must be preferred.
+        * On other filesystems (e.g. btrfs) the statfs64 uuid contains
+        * important info that the blkid uuid cannot contain:  This happens
+        * when multiple subvolumes are exported (they have the same
+        * blkid uuid but different statfs64 uuids).
+        * We rely on get_uuid_blkdev *knowing* which is which and not returning
+        * a uuid for filesystems where the statfs64 uuid is better.
+        *
+        */
+       struct statfs64 st;
+       char fsid_val[17];
+       const char *blkid_val;
+       const char *val;
+
+       blkid_val = get_uuid_blkdev(path);
+
+       if (statfs64(path, &st) == 0 &&
+           (st.f_fsid.__val[0] || st.f_fsid.__val[1]))
+               snprintf(fsid_val, 17, "%08x%08x",
+                        st.f_fsid.__val[0], st.f_fsid.__val[1]);
+       else
+               fsid_val[0] = 0;
+
+       if (blkid_val && (type--) == 0)
+               val = blkid_val;
+       else if (fsid_val[0] && (type--) == 0)
+               val = fsid_val;
+       else
+               return 0;
+
+       get_uuid(val, uuidlen, uuid);
+       return 1;
+}
 
 /* Iterate through /etc/mtab, finding mountpoints
  * at or below a given path
@@ -247,60 +341,49 @@ static char *next_mnt(void **v, char *p)
        return me->mnt_dir;
 }
 
-void nfsd_fh(FILE *f)
+/* True iff e1 is a child of e2 and e2 has crossmnt set: */
+static bool subexport(struct exportent *e1, struct exportent *e2)
 {
-       /* request are:
-        *  domain fsidtype fsid
-        * interpret fsid, find export point and options, and write:
-        *  domain fsidtype fsid expiry path
-        */
-       char *cp;
-       char *dom;
-       int fsidtype;
-       int fsidlen;
-       unsigned int dev, major=0, minor=0;
-       unsigned int inode=0;
-       unsigned long long inode64;
-       unsigned int fsidnum=0;
-       char fsid[32];
-       struct exportent *found = NULL;
-       char *found_path = NULL;
-       nfs_export *exp;
-       int i;
-       int dev_missing = 0;
-       int uuidlen = 0;
-       char *fhuuid = NULL;
+       char *p1 = e1->e_path, *p2 = e2->e_path;
+       int l2 = strlen(p2);
 
-       if (readline(fileno(f), &lbuf, &lbuflen) != 1)
-               return;
+       return e2->e_flags & NFSEXP_CROSSMOUNT
+              && strncmp(p1, p2, l2) == 0
+              && p1[l2] == '/';
+}
 
-       cp = lbuf;
+struct parsed_fsid {
+       int fsidtype;
+       /* We could use a union for this, but it would be more
+        * complicated; why bother? */
+       unsigned int inode;
+       unsigned int minor;
+       unsigned int major;
+       unsigned int fsidnum;
+       int uuidlen;
+       char *fhuuid;
+};
 
-       dom = malloc(strlen(cp));
-       if (dom == NULL)
-               return;
-       if (qword_get(&cp, dom, strlen(cp)) <= 0)
-               goto out;
-       if (qword_get_int(&cp, &fsidtype) != 0)
-               goto out;
-       if (fsidtype < 0 || fsidtype > 7)
-               goto out; /* unknown type */
-       if ((fsidlen = qword_get(&cp, fsid, 32)) <= 0)
-               goto out;
+int parse_fsid(int fsidtype, int fsidlen, char *fsid, struct parsed_fsid *parsed)
+{
+       unsigned int dev;
+       unsigned long long inode64;
+
+       parsed->fsidtype = fsidtype;
        switch(fsidtype) {
        case FSID_DEV: /* 4 bytes: 2 major, 2 minor, 4 inode */
                if (fsidlen != 8)
-                       goto out;
+                       return -1;
                memcpy(&dev, fsid, 4);
-               memcpy(&inode, fsid+4, 4);
-               major = ntohl(dev)>>16;
-               minor = ntohl(dev) & 0xFFFF;
+               memcpy(&parsed->inode, fsid+4, 4);
+               parsed->major = ntohl(dev)>>16;
+               parsed->minor = ntohl(dev) & 0xFFFF;
                break;
 
        case FSID_NUM: /* 4 bytes - fsid */
                if (fsidlen != 4)
-                       goto out;
-               memcpy(&fsidnum, fsid, 4);
+                       return -1;
+               memcpy(&parsed->fsidnum, fsid, 4);
                break;
 
        case FSID_MAJOR_MINOR: /* 12 bytes: 4 major, 4 minor, 4 inode 
@@ -308,10 +391,12 @@ void nfsd_fh(FILE *f)
                 * an historical accident
                 */
                if (fsidlen != 12)
-                       goto out;
-               memcpy(&dev, fsid, 4); major = ntohl(dev);
-               memcpy(&dev, fsid+4, 4); minor = ntohl(dev);
-               memcpy(&inode, fsid+8, 4);
+                       return -1;
+               memcpy(&dev, fsid, 4);
+               parsed->major = ntohl(dev);
+               memcpy(&dev, fsid+4, 4);
+               parsed->minor = ntohl(dev);
+               memcpy(&parsed->inode, fsid+8, 4);
                break;
 
        case FSID_ENCODE_DEV: /* 8 bytes: 4 byte packed device number, 4 inode */
@@ -319,50 +404,144 @@ void nfsd_fh(FILE *f)
                 * no-one outside this host has any business interpreting it
                 */
                if (fsidlen != 8)
-                       goto out;
+                       return -1;
                memcpy(&dev, fsid, 4);
-               memcpy(&inode, fsid+4, 4);
-               major = (dev & 0xfff00) >> 8;
-               minor = (dev & 0xff) | ((dev >> 12) & 0xfff00);
+               memcpy(&parsed->inode, fsid+4, 4);
+               parsed->major = (dev & 0xfff00) >> 8;
+               parsed->minor = (dev & 0xff) | ((dev >> 12) & 0xfff00);
                break;
 
        case FSID_UUID4_INUM: /* 4 byte inode number and 4 byte uuid */
                if (fsidlen != 8)
-                       goto out;
-               memcpy(&inode, fsid, 4);
-               uuidlen = 4;
-               fhuuid = fsid+4;
+                       return -1;
+               memcpy(&parsed->inode, fsid, 4);
+               parsed->uuidlen = 4;
+               parsed->fhuuid = fsid+4;
                break;
        case FSID_UUID8: /* 8 byte uuid */
                if (fsidlen != 8)
-                       goto out;
-               uuidlen = 8;
-               fhuuid = fsid;
+                       return -1;
+               parsed->uuidlen = 8;
+               parsed->fhuuid = fsid;
                break;
        case FSID_UUID16: /* 16 byte uuid */
                if (fsidlen != 16)
-                       goto out;
-               uuidlen = 16;
-               fhuuid = fsid;
+                       return -1;
+               parsed->uuidlen = 16;
+               parsed->fhuuid = fsid;
                break;
        case FSID_UUID16_INUM: /* 8 byte inode number and 16 byte uuid */
                if (fsidlen != 24)
-                       goto out;
+                       return -1;
                memcpy(&inode64, fsid, 8);
-               inode = inode64;
-               uuidlen = 16;
-               fhuuid = fsid+8;
+               parsed->inode = inode64;
+               parsed->uuidlen = 16;
+               parsed->fhuuid = fsid+8;
                break;
        }
+       return 0;
+}
+
+static bool match_fsid(struct parsed_fsid *parsed, nfs_export *exp, char *path)
+{
+       struct stat stb;
+       int type;
+       char u[16];
+
+       if (stat(path, &stb) != 0)
+               return false;
+       if (!S_ISDIR(stb.st_mode) && !S_ISREG(stb.st_mode))
+               return false;
+
+       switch (parsed->fsidtype) {
+       case FSID_DEV:
+       case FSID_MAJOR_MINOR:
+       case FSID_ENCODE_DEV:
+               if (stb.st_ino != parsed->inode)
+                       return false;
+               if (parsed->major != major(stb.st_dev) ||
+                   parsed->minor != minor(stb.st_dev))
+                       return false;
+               return true;
+       case FSID_NUM:
+               if (((exp->m_export.e_flags & NFSEXP_FSID) == 0 ||
+                    exp->m_export.e_fsid != parsed->fsidnum))
+                       return false;
+               return true;
+       case FSID_UUID4_INUM:
+       case FSID_UUID16_INUM:
+               if (stb.st_ino != parsed->inode)
+                       return false;
+               goto check_uuid;
+       case FSID_UUID8:
+       case FSID_UUID16:
+               if (!is_mountpoint(path))
+                       return false;
+       check_uuid:
+               if (exp->m_export.e_uuid)
+                       get_uuid(exp->m_export.e_uuid, parsed->uuidlen, u);
+               else
+                       for (type = 0;
+                            uuid_by_path(path, type, parsed->uuidlen, u);
+                            type++)
+                               if (memcmp(u, parsed->fhuuid, parsed->uuidlen) == 0)
+                                       return true;
+
+               if (memcmp(u, parsed->fhuuid, parsed->uuidlen) != 0)
+                       return false;
+               return true;
+       }
+       /* Well, unreachable, actually: */
+       return false;
+}
+
+static void nfsd_fh(FILE *f)
+{
+       /* request are:
+        *  domain fsidtype fsid
+        * interpret fsid, find export point and options, and write:
+        *  domain fsidtype fsid expiry path
+        */
+       char *cp;
+       char *dom;
+       int fsidtype;
+       int fsidlen;
+       char fsid[32];
+       struct parsed_fsid parsed;
+       struct exportent *found = NULL;
+       struct addrinfo *ai = NULL;
+       char *found_path = NULL;
+       nfs_export *exp;
+       int i;
+       int dev_missing = 0;
+
+       if (readline(fileno(f), &lbuf, &lbuflen) != 1)
+               return;
+
+       xlog(D_CALL, "nfsd_fh: inbuf '%s'", lbuf);
+
+       cp = lbuf;
+
+       dom = malloc(strlen(cp));
+       if (dom == NULL)
+               return;
+       if (qword_get(&cp, dom, strlen(cp)) <= 0)
+               goto out;
+       if (qword_get_int(&cp, &fsidtype) != 0)
+               goto out;
+       if (fsidtype < 0 || fsidtype > 7)
+               goto out; /* unknown type */
+       if ((fsidlen = qword_get(&cp, fsid, 32)) <= 0)
+               goto out;
+       if (parse_fsid(fsidtype, fsidlen, fsid, &parsed))
+               goto out;
 
        auth_reload();
 
        /* Now determine export point for this fsid/domain */
        for (i=0 ; i < MCL_MAXTYPES; i++) {
                nfs_export *next_exp;
-               for (exp = exportlist[i]; exp; exp = next_exp) {
-                       struct stat stb;
-                       char u[16];
+               for (exp = exportlist[i].p_head; exp; exp = next_exp) {
                        char *path;
 
                        if (exp->m_export.e_flags & NFSEXP_CROSSMOUNT) {
@@ -389,63 +568,36 @@ void nfsd_fh(FILE *f)
                                next_exp = exp->m_next;
                        }
 
-                       if (!client_member(dom, exp->m_client->m_hostname))
+                       if (!use_ipaddr && !client_member(dom, exp->m_client->m_hostname))
                                continue;
                        if (exp->m_export.e_mountpoint &&
                            !is_mountpoint(exp->m_export.e_mountpoint[0]?
                                           exp->m_export.e_mountpoint:
                                           exp->m_export.e_path))
                                dev_missing ++;
-                       if (stat(path, &stb) != 0)
-                               continue;
-                       if (!S_ISDIR(stb.st_mode) && !S_ISREG(stb.st_mode)) {
-                               continue;
-                       }
-                       switch(fsidtype){
-                       case FSID_DEV:
-                       case FSID_MAJOR_MINOR:
-                       case FSID_ENCODE_DEV:
-                               if (stb.st_ino != inode)
-                                       continue;
-                               if (major != major(stb.st_dev) ||
-                                   minor != minor(stb.st_dev))
-                                       continue;
-                               break;
-                       case FSID_NUM:
-                               if (((exp->m_export.e_flags & NFSEXP_FSID) == 0 ||
-                                    exp->m_export.e_fsid != fsidnum))
-                                       continue;
-                               break;
-                       case FSID_UUID4_INUM:
-                       case FSID_UUID16_INUM:
-                               if (stb.st_ino != inode)
-                                       continue;
-                               goto check_uuid;
-                       case FSID_UUID8:
-                       case FSID_UUID16:
-                               if (!is_mountpoint(path))
-                                       continue;
-                       check_uuid:
-#if USE_BLKID
-                               if (exp->m_export.e_uuid)
-                                       get_uuid(NULL, exp->m_export.e_uuid,
-                                                uuidlen, u);
-                               else if (get_uuid(path, NULL,
-                                                 uuidlen, u) == 0)
-                                       continue;
 
-                               if (memcmp(u, fhuuid, uuidlen) != 0)
-                                       continue;
-                               break;
-#else
+                       if (!match_fsid(&parsed, exp, path))
                                continue;
-#endif
+                       if (use_ipaddr) {
+                               if (ai == NULL) {
+                                       struct addrinfo *tmp;
+                                       tmp = host_pton(dom);
+                                       if (tmp == NULL)
+                                               goto out;
+                                       ai = client_resolve(tmp->ai_addr);
+                                       freeaddrinfo(tmp);
+                               }
+                               if (!client_check(exp->m_client, ai))
+                                       continue;
                        }
-                       /* It's a match !! */
-                       if (!found) {
+                       if (!found || subexport(&exp->m_export, found)) {
                                found = &exp->m_export;
+                               free(found_path);
                                found_path = strdup(path);
-                       } else if (strcmp(found->e_path, exp->m_export.e_path)!= 0)
+                               if (found_path == NULL)
+                                       goto out;
+                       } else if (strcmp(found->e_path, exp->m_export.e_path)
+                                  && !subexport(found, &exp->m_export))
                        {
                                xlog(L_WARNING, "%s and %s have same filehandle for %s, using first",
                                     found_path, path, dom);
@@ -489,21 +641,25 @@ void nfsd_fh(FILE *f)
         */
        qword_printint(f, 0x7fffffff);
        if (found)
-               qword_print(f, found->e_path);
+               qword_print(f, found_path);
        qword_eol(f);
  out:
+       if (found_path)
+               free(found_path);
+       freeaddrinfo(ai);
        free(dom);
+       xlog(D_CALL, "nfsd_fh: found %p path %s", found, found ? found->e_path : NULL);
        return;         
 }
 
-static void write_fsloc(FILE *f, struct exportent *ep, char *path)
+static void write_fsloc(FILE *f, struct exportent *ep)
 {
        struct servers *servers;
 
        if (ep->e_fslocmethod == FSLOC_NONE)
                return;
 
-       servers = replicas_lookup(ep->e_fslocmethod, ep->e_fslocdata, path);
+       servers = replicas_lookup(ep->e_fslocmethod, ep->e_fslocdata);
        if (!servers)
                return;
        qword_print(f, "fsloc");
@@ -519,7 +675,7 @@ static void write_fsloc(FILE *f, struct exportent *ep, char *path)
        release_replicas(servers);
 }
 
-static void write_secinfo(FILE *f, struct exportent *ep)
+static void write_secinfo(FILE *f, struct exportent *ep, int flag_mask)
 {
        struct sec_entry *p;
 
@@ -533,7 +689,7 @@ static void write_secinfo(FILE *f, struct exportent *ep)
        qword_printint(f, p - ep->e_secinfo);
        for (p = ep->e_secinfo; p->flav; p++) {
                qword_printint(f, p->flav->fnum);
-               qword_printint(f, p->flags);
+               qword_printint(f, p->flags & flag_mask);
        }
 
 }
@@ -542,89 +698,90 @@ static int dump_to_cache(FILE *f, char *domain, char *path, struct exportent *ex
 {
        qword_print(f, domain);
        qword_print(f, path);
-       qword_printint(f, time(0)+30*60);
        if (exp) {
-               qword_printint(f, exp->e_flags);
+               int different_fs = strcmp(path, exp->e_path) != 0;
+               int flag_mask = different_fs ? ~NFSEXP_FSID : ~0;
+
+               qword_printuint(f, time(0) + exp->e_ttl);
+               qword_printint(f, exp->e_flags & flag_mask);
                qword_printint(f, exp->e_anonuid);
                qword_printint(f, exp->e_anongid);
                qword_printint(f, exp->e_fsid);
-               write_fsloc(f, exp, path);
-               write_secinfo(f, exp);
-#if USE_BLKID
-               if (exp->e_uuid == NULL) {
+               write_fsloc(f, exp);
+               write_secinfo(f, exp, flag_mask);
+               if (exp->e_uuid == NULL || different_fs) {
                        char u[16];
-                       if (get_uuid(path, NULL, 16, u)) {
+                       if (uuid_by_path(path, 0, 16, u)) {
                                qword_print(f, "uuid");
                                qword_printhex(f, u, 16);
                        }
-               } else if (exp->e_uuid) {
+               } else {
+                       char u[16];
+                       get_uuid(exp->e_uuid, 16, u);
                        qword_print(f, "uuid");
-                       qword_printhex(f, exp->e_uuid, 16);
+                       qword_printhex(f, u, 16);
                }
-#endif
-       }
+       } else
+               qword_printuint(f, time(0) + DEFAULT_TTL);
        return qword_eol(f);
 }
 
-void nfsd_export(FILE *f)
+static int is_subdirectory(char *child, char *parent)
 {
-       /* requests are:
-        *  domain path
-        * determine export options and return:
-        *  domain path expiry flags anonuid anongid fsid
-        */
-
-       char *cp;
-       int i;
-       char *dom, *path;
-       nfs_export *exp, *found = NULL;
-       int found_type = 0;
-
+       int l = strlen(parent);
 
-       if (readline(fileno(f), &lbuf, &lbuflen) != 1)
-               return;
+       return strcmp(child, parent) == 0
+               || (strncmp(child, parent, l) == 0 && child[l] == '/');
+}
 
-       cp = lbuf;
-       dom = malloc(strlen(cp));
-       path = malloc(strlen(cp));
+static int path_matches(nfs_export *exp, char *path)
+{
+       if (exp->m_export.e_flags & NFSEXP_CROSSMOUNT)
+               return is_subdirectory(path, exp->m_export.e_path);
+       return strcmp(path, exp->m_export.e_path) == 0;
+}
 
-       if (!dom || !path)
-               goto out;
+static int
+client_matches(nfs_export *exp, char *dom, struct addrinfo *ai)
+{
+       if (use_ipaddr)
+               return client_check(exp->m_client, ai);
+       return client_member(dom, exp->m_client->m_hostname);
+}
 
-       if (qword_get(&cp, dom, strlen(lbuf)) <= 0)
-               goto out;
-       if (qword_get(&cp, path, strlen(lbuf)) <= 0)
-               goto out;
+static int
+export_matches(nfs_export *exp, char *dom, char *path, struct addrinfo *ai)
+{
+       return path_matches(exp, path) && client_matches(exp, dom, ai);
+}
 
-       auth_reload();
+static nfs_export *
+lookup_export(char *dom, char *path, struct addrinfo *ai)
+{
+       nfs_export *exp;
+       nfs_export *found = NULL;
+       int found_type = 0;
+       int i;
 
-       /* now find flags for this export point in this domain */
        for (i=0 ; i < MCL_MAXTYPES; i++) {
-               for (exp = exportlist[i]; exp; exp = exp->m_next) {
-                       if (!client_member(dom, exp->m_client->m_hostname))
-                               continue;
-                       if (exp->m_export.e_flags & NFSEXP_CROSSMOUNT) {
-                               /* if path is a mountpoint below e_path, then OK */
-                               int l = strlen(exp->m_export.e_path);
-                               if (strcmp(path, exp->m_export.e_path) == 0 ||
-                                   (strncmp(path, exp->m_export.e_path, l) == 0 &&
-                                    path[l] == '/' &&
-                                    is_mountpoint(path)))
-                                       /* ok */;
-                               else
-                                       continue;
-                       } else if (strcmp(path, exp->m_export.e_path) != 0)
+               for (exp = exportlist[i].p_head; exp; exp = exp->m_next) {
+                       if (!export_matches(exp, dom, path, ai))
                                continue;
                        if (!found) {
                                found = exp;
                                found_type = i;
                                continue;
                        }
+
+                       /* Always prefer non-V4ROOT mounts */
+                       if (found->m_export.e_flags & NFSEXP_V4ROOT)
+                               continue;
+
                        /* If one is a CROSSMOUNT, then prefer the longest path */
                        if (((found->m_export.e_flags & NFSEXP_CROSSMOUNT) ||
-                            (found->m_export.e_flags & NFSEXP_CROSSMOUNT)) &&
+                            (exp->m_export.e_flags & NFSEXP_CROSSMOUNT)) &&
                            strlen(found->m_export.e_path) !=
-                           strlen(found->m_export.e_path)) {
+                           strlen(exp->m_export.e_path)) {
 
                                if (strlen(exp->m_export.e_path) >
                                    strlen(found->m_export.e_path)) {
@@ -642,6 +799,52 @@ void nfsd_export(FILE *f)
                        }
                }
        }
+       return found;
+}
+
+static void nfsd_export(FILE *f)
+{
+       /* requests are:
+        *  domain path
+        * determine export options and return:
+        *  domain path expiry flags anonuid anongid fsid
+        */
+
+       char *cp;
+       char *dom, *path;
+       nfs_export *found = NULL;
+       struct addrinfo *ai = NULL;
+
+       if (readline(fileno(f), &lbuf, &lbuflen) != 1)
+               return;
+
+       xlog(D_CALL, "nfsd_export: inbuf '%s'", lbuf);
+
+       cp = lbuf;
+       dom = malloc(strlen(cp));
+       path = malloc(strlen(cp));
+
+       if (!dom || !path)
+               goto out;
+
+       if (qword_get(&cp, dom, strlen(lbuf)) <= 0)
+               goto out;
+       if (qword_get(&cp, path, strlen(lbuf)) <= 0)
+               goto out;
+
+       auth_reload();
+
+       if (use_ipaddr) {
+               struct addrinfo *tmp;
+               tmp = host_pton(dom);
+               if (tmp == NULL)
+                       goto out;
+               ai = client_resolve(tmp->ai_addr);
+               freeaddrinfo(tmp);
+                       goto out;
+       }
+
+       found = lookup_export(dom, path, ai);
 
        if (found) {
                if (dump_to_cache(f, dom, path, &found->m_export) < 0) {
@@ -654,8 +857,10 @@ void nfsd_export(FILE *f)
                dump_to_cache(f, dom, path, NULL);
        }
  out:
+       xlog(D_CALL, "nfsd_export: found %p path %s", found, path ? path : NULL);
        if (dom) free(dom);
        if (path) free(path);
+       freeaddrinfo(ai);
 }
 
 
@@ -663,15 +868,21 @@ struct {
        char *cache_name;
        void (*cache_handle)(FILE *f);
        FILE *f;
+       char vbuf[RPC_CHAN_BUF_SIZE];
 } cachelist[] = {
-       { "auth.unix.ip", auth_unix_ip},
-       { "auth.unix.gid", auth_unix_gid},
-       { "nfsd.export", nfsd_export},
-       { "nfsd.fh", nfsd_fh},
-       { NULL, NULL }
+       { "auth.unix.ip", auth_unix_ip, NULL, ""},
+       { "auth.unix.gid", auth_unix_gid, NULL, ""},
+       { "nfsd.export", nfsd_export, NULL, ""},
+       { "nfsd.fh", nfsd_fh, NULL, ""},
+       { NULL, NULL, NULL, ""}
 };
 
 extern int manage_gids;
+
+/**
+ * cache_open - prepare communications channels with kernel RPC caches
+ *
+ */
 void cache_open(void) 
 {
        int i;
@@ -681,9 +892,17 @@ void cache_open(void)
                        continue;
                sprintf(path, "/proc/net/rpc/%s/channel", cachelist[i].cache_name);
                cachelist[i].f = fopen(path, "r+");
+               if (cachelist[i].f != NULL) {
+                       setvbuf(cachelist[i].f, cachelist[i].vbuf, _IOLBF, 
+                               RPC_CHAN_BUF_SIZE);
+               }
        }
 }
 
+/**
+ * cache_set_fds - prepare cache file descriptors for one iteration of the service loop
+ * @fdset: pointer to fd_set to prepare
+ */
 void cache_set_fds(fd_set *fdset)
 {
        int i;
@@ -693,6 +912,10 @@ void cache_set_fds(fd_set *fdset)
        }
 }
 
+/**
+ * cache_process_req - process any active cache file descriptors during service loop iteration
+ * @fdset: pointer to fd_set to examine for activity
+ */
 int cache_process_req(fd_set *readfds) 
 {
        int i;
@@ -711,11 +934,11 @@ int cache_process_req(fd_set *readfds)
 
 /*
  * Give IP->domain and domain+path->options to kernel
- * % echo nfsd $IP  $[now+30*60] $domain > /proc/net/rpc/auth.unix.ip/channel
- * % echo $domain $path $[now+30*60] $options $anonuid $anongid $fsid > /proc/net/rpc/nfsd.export/channel
+ * % echo nfsd $IP  $[now+DEFAULT_TTL] $domain > /proc/net/rpc/auth.unix.ip/channel
+ * % echo $domain $path $[now+DEFAULT_TTL] $options $anonuid $anongid $fsid > /proc/net/rpc/nfsd.export/channel
  */
 
-int cache_export_ent(char *domain, struct exportent *exp, char *path)
+static int cache_export_ent(char *domain, struct exportent *exp, char *path)
 {
        int err;
        FILE *f = fopen("/proc/net/rpc/nfsd.export/channel", "w");
@@ -736,8 +959,8 @@ int cache_export_ent(char *domain, struct exportent *exp, char *path)
                 * and export them with the same options
                 */
                struct stat stb;
-               int l = strlen(exp->e_path);
-               int dev;
+               size_t l = strlen(exp->e_path);
+               __dev_t dev;
 
                if (strlen(path) <= l || path[l] != '/' ||
                    strncmp(exp->e_path, path, l) != 0)
@@ -773,8 +996,14 @@ int cache_export_ent(char *domain, struct exportent *exp, char *path)
        return err;
 }
 
+/**
+ * cache_export - Inform kernel of a new nfs_export
+ * @exp: target nfs_export
+ * @path: NUL-terminated C string containing export path
+ */
 int cache_export(nfs_export *exp, char *path)
 {
+       char buf[INET6_ADDRSTRLEN];
        int err;
        FILE *f;
 
@@ -782,9 +1011,11 @@ int cache_export(nfs_export *exp, char *path)
        if (!f)
                return -1;
 
+
        qword_print(f, "nfsd");
-       qword_print(f, inet_ntoa(exp->m_client->m_addrlist[0]));
-       qword_printint(f, time(0)+30*60);
+       qword_print(f,
+               host_ntop(get_addrlist(exp->m_client, 0), buf, sizeof(buf)));
+       qword_printuint(f, time(0) + exp->m_export.e_ttl);
        qword_print(f, exp->m_client->m_hostname);
        err = qword_eol(f);
        
@@ -795,7 +1026,14 @@ int cache_export(nfs_export *exp, char *path)
        return err;
 }
 
-/* Get a filehandle.
+/**
+ * cache_get_filehandle - given an nfs_export, get its root filehandle
+ * @exp: target nfs_export
+ * @len: length of requested file handle
+ * @p: NUL-terminated C string containing export path
+ *
+ * Returns pointer to NFS file handle of root directory of export
+ *
  * { 
  *   echo $domain $path $length 
  *   read filehandle <&0
@@ -829,4 +1067,3 @@ cache_get_filehandle(nfs_export *exp, int len, char *p)
        fh.fh_size = qword_get(&bp, (char *)fh.fh_handle, NFS3_FHSIZE);
        return &fh;
 }
-