]> git.decadent.org.uk Git - nfs-utils.git/blobdiff - utils/mountd/cache.c
mountd: Ensure cache downcall can handle IPv6 addresses
[nfs-utils.git] / utils / mountd / cache.c
index 23e2344559bb3bec48583c3a15d0187c44c03a3d..f70f4d6e81a7e1ee7b57061f34b7d1c6d68ba162 100644 (file)
 #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,
@@ -57,14 +62,14 @@ 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);
 
 
 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
@@ -75,10 +80,10 @@ void auth_unix_ip(FILE *f)
         */
        char *cp;
        char class[20];
-       char ipaddr[20];
+       char ipaddr[INET6_ADDRSTRLEN];
        char *client = NULL;
-       struct in_addr addr;
-       struct hostent *he = NULL;
+       struct addrinfo *tmp = NULL;
+       struct addrinfo *ai = NULL;
        if (readline(fileno(f), &lbuf, &lbuflen) != 1)
                return;
 
@@ -90,20 +95,23 @@ void auth_unix_ip(FILE *f)
            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... */
        if (!use_ipaddr) {
-               he = client_resolve(addr);
-               client = client_compose(he);
+               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);
@@ -114,18 +122,17 @@ void auth_unix_ip(FILE *f)
        qword_eol(f);
        xlog(D_CALL, "auth_unix_ip: client %p '%s'", client, client?client: "DEFAULT");
 
-       if (client) free(client);
-       free(he);
+       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;
@@ -136,7 +143,7 @@ void auth_unix_gid(FILE *f)
                return;
 
        cp = lbuf;
-       if (qword_get_int(&cp, &uid) != 0)
+       if (qword_get_uint(&cp, &uid) != 0)
                return;
 
        pw = getpwuid(uid);
@@ -153,14 +160,14 @@ void auth_unix_gid(FILE *f)
                                                  groups, &ngroups);
                }
        }
-       qword_printint(f, uid);
-       qword_printint(f, time(0)+30*60);
+       qword_printuint(f, uid);
+       qword_printuint(f, time(0)+30*60);
        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_printint(f, 0);
+               qword_printuint(f, 0);
        qword_eol(f);
 
        if (groups != glist)
@@ -170,13 +177,16 @@ void auth_unix_gid(FILE *f)
 #if USE_BLKID
 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 = NULL;
+       const char *val, *uuid = NULL;
 
        if (cache == NULL)
                blkid_get_cache(&cache, NULL);
@@ -193,33 +203,29 @@ static const char *get_uuid_blkdev(char *path)
        iter = blkid_tag_iterate_begin(dev);
        if (!iter)
                return NULL;
-       while (blkid_tag_next(iter, &type, &val) == 0)
+       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 val;
+       return uuid;
 }
 #else
 #define get_uuid_blkdev(path) (NULL)
 #endif
 
-int get_uuid(char *path, char *uuid, int uuidlen, char *u)
+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 = NULL;
-       char fsid_val[17];
-
-       if (path) {
-               val = get_uuid_blkdev(path);
-               if (!val)
-                       return 0;
-       } else {
-               val = uuid;
-       }
        
        memset(u, 0, uuidlen);
        for ( ; *val ; val++) {
@@ -243,6 +249,60 @@ int get_uuid(char *path, char *uuid, int uuidlen, char *u)
        return 1;
 }
 
+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
  */
@@ -268,7 +328,7 @@ static char *next_mnt(void **v, char *p)
        return me->mnt_dir;
 }
 
-void nfsd_fh(FILE *f)
+static void nfsd_fh(FILE *f)
 {
        /* request are:
         *  domain fsidtype fsid
@@ -285,8 +345,7 @@ void nfsd_fh(FILE *f)
        unsigned int fsidnum=0;
        char fsid[32];
        struct exportent *found = NULL;
-       struct hostent *he = NULL;
-       struct in_addr addr;
+       struct addrinfo *ai = NULL;
        char *found_path = NULL;
        nfs_export *exp;
        int i;
@@ -385,10 +444,11 @@ void nfsd_fh(FILE *f)
        /* 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) {
+               for (exp = exportlist[i].p_head; exp; exp = next_exp) {
                        struct stat stb;
                        char u[16];
                        char *path;
+                       int type;
 
                        if (exp->m_export.e_flags & NFSEXP_CROSSMOUNT) {
                                static nfs_export *prev = NULL;
@@ -452,22 +512,29 @@ void nfsd_fh(FILE *f)
                                        continue;
                        check_uuid:
                                if (exp->m_export.e_uuid)
-                                       get_uuid(NULL, exp->m_export.e_uuid,
+                                       get_uuid(exp->m_export.e_uuid,
                                                 uuidlen, u);
-                               else if (get_uuid(path, NULL, uuidlen, u) == 0)
-                                       continue;
+                               else
+                                       for (type = 0;
+                                            uuid_by_path(path, type, uuidlen, u);
+                                            type++)
+                                               if (memcmp(u, fhuuid, uuidlen) == 0)
+                                                       break;
 
                                if (memcmp(u, fhuuid, uuidlen) != 0)
                                        continue;
                                break;
                        }
                        if (use_ipaddr) {
-                               if (he == NULL) {
-                                       if (!inet_aton(dom, &addr))
+                               if (ai == NULL) {
+                                       struct addrinfo *tmp;
+                                       tmp = host_pton(dom);
+                                       if (tmp == NULL)
                                                goto out;
-                                       he = client_resolve(addr);
+                                       ai = client_resolve(tmp->ai_addr);
+                                       freeaddrinfo(tmp);
                                }
-                               if (!client_check(exp->m_client, he))
+                               if (!client_check(exp->m_client, ai))
                                        continue;
                        }
                        /* It's a match !! */
@@ -525,21 +592,20 @@ void nfsd_fh(FILE *f)
  out:
        if (found_path)
                free(found_path);
-       if (he)
-               free(he);
+       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");
@@ -555,7 +621,7 @@ 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;
 
@@ -569,7 +635,7 @@ 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);
        }
 
 }
@@ -581,25 +647,23 @@ static int dump_to_cache(FILE *f, char *domain, char *path, struct exportent *ex
        qword_printint(f, time(0)+30*60);
        if (exp) {
                int different_fs = strcmp(path, exp->e_path) != 0;
-               
-               if (different_fs)
-                       qword_printint(f, exp->e_flags & ~NFSEXP_FSID);
-               else
-                       qword_printint(f, exp->e_flags);
+               int flag_mask = different_fs ? ~NFSEXP_FSID : ~0;
+
+               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);
+               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 {
                        char u[16];
-                       get_uuid(NULL, exp->e_uuid, 16, u);
+                       get_uuid(exp->e_uuid, 16, u);
                        qword_print(f, "uuid");
                        qword_printhex(f, u, 16);
                }
@@ -607,73 +671,57 @@ static int dump_to_cache(FILE *f, char *domain, char *path, struct exportent *ex
        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
-        */
+       int l = strlen(parent);
 
-       char *cp;
-       int i;
-       char *dom, *path;
-       nfs_export *exp, *found = NULL;
-       int found_type = 0;
-       struct in_addr addr;
-       struct hostent *he = NULL;
-
-
-       if (readline(fileno(f), &lbuf, &lbuflen) != 1)
-               return;
-
-       xlog(D_CALL, "nfsd_export: inbuf '%s'", lbuf);
+       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 (!use_ipaddr && !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 (use_ipaddr) {
-                               if (he == NULL) {
-                                       if (!inet_aton(dom, &addr))
-                                               goto out;
-                                       he = client_resolve(addr);
-                               }
-                               if (!client_check(exp->m_client, he))
-                                       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) ||
                             (exp->m_export.e_flags & NFSEXP_CROSSMOUNT)) &&
@@ -696,6 +744,52 @@ 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) {
@@ -711,7 +805,7 @@ void nfsd_export(FILE *f)
        xlog(D_CALL, "nfsd_export: found %p path %s", found, path ? path : NULL);
        if (dom) free(dom);
        if (path) free(path);
-       if (he) free(he);
+       freeaddrinfo(ai);
 }
 
 
@@ -720,14 +814,19 @@ struct {
        void (*cache_handle)(FILE *f);
        FILE *f;
 } 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;
@@ -740,6 +839,10 @@ void cache_open(void)
        }
 }
 
+/**
+ * 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;
@@ -749,6 +852,10 @@ 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;
@@ -771,7 +878,7 @@ int cache_process_req(fd_set *readfds)
  * % echo $domain $path $[now+30*60] $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");
@@ -792,8 +899,8 @@ 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)
@@ -829,8 +936,14 @@ 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;
 
@@ -838,8 +951,10 @@ 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_print(f,
+               host_ntop(get_addrlist(exp->m_client, 0), buf, sizeof(buf)));
        qword_printint(f, time(0)+30*60);
        qword_print(f, exp->m_client->m_hostname);
        err = qword_eol(f);
@@ -851,7 +966,14 @@ 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
@@ -885,4 +1007,3 @@ cache_get_filehandle(nfs_export *exp, int len, char *p)
        fh.fh_size = qword_get(&bp, (char *)fh.fh_handle, NFS3_FHSIZE);
        return &fh;
 }
-