]> git.decadent.org.uk Git - nfs-utils.git/blobdiff - utils/mountd/cache.c
mountd: clean up cache API
[nfs-utils.git] / utils / mountd / cache.c
index caef5b235c692804af81e2c3a569ef43d5928807..ab873d56ba4bb37eb36360613e5f5f132a7be26a 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
@@ -77,8 +82,8 @@ void auth_unix_ip(FILE *f)
        char class[20];
        char ipaddr[20];
        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;
 
@@ -93,17 +98,20 @@ void auth_unix_ip(FILE *f)
        if (qword_get(&cp, ipaddr, 20) <= 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);
@@ -114,11 +122,10 @@ 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
@@ -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);
@@ -193,42 +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) {
-                       struct statfs64 st;
-
-                       if (statfs64(path, &st))
-                               return 0;
-                       if (!st.f_fsid.__val[0] && !st.f_fsid.__val[1])
-                               return 0;
-                       snprintf(fsid_val, 17, "%08x%08x",
-                                st.f_fsid.__val[0], st.f_fsid.__val[1]);
-                       val = fsid_val;
-               }
-       } else {
-               val = uuid;
-       }
        
        memset(u, 0, uuidlen);
        for ( ; *val ; val++) {
@@ -252,6 +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
  */
@@ -277,7 +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
@@ -294,8 +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;
@@ -398,6 +448,7 @@ void nfsd_fh(FILE *f)
                        struct stat stb;
                        char u[16];
                        char *path;
+                       int type;
 
                        if (exp->m_export.e_flags & NFSEXP_CROSSMOUNT) {
                                static nfs_export *prev = NULL;
@@ -461,22 +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 !! */
@@ -534,21 +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");
@@ -596,17 +653,17 @@ static int dump_to_cache(FILE *f, char *domain, char *path, struct exportent *ex
                qword_printint(f, exp->e_anonuid);
                qword_printint(f, exp->e_anongid);
                qword_printint(f, exp->e_fsid);
-               write_fsloc(f, exp, path);
+               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);
                }
@@ -629,19 +686,22 @@ static int path_matches(nfs_export *exp, char *path)
        return strcmp(path, exp->m_export.e_path) == 0;
 }
 
-static int client_matches(nfs_export *exp, char *dom, struct hostent *he)
+static int
+client_matches(nfs_export *exp, char *dom, struct addrinfo *ai)
 {
        if (use_ipaddr)
-               return client_check(exp->m_client, he);
+               return client_check(exp->m_client, ai);
        return client_member(dom, exp->m_client->m_hostname);
 }
 
-static int export_matches(nfs_export *exp, char *dom, char *path, struct hostent *he)
+static int
+export_matches(nfs_export *exp, char *dom, char *path, struct addrinfo *ai)
 {
-       return path_matches(exp, path) && client_matches(exp, dom, he);
+       return path_matches(exp, path) && client_matches(exp, dom, ai);
 }
 
-static nfs_export *lookup_export(char *dom, char *path, struct hostent *he)
+static nfs_export *
+lookup_export(char *dom, char *path, struct addrinfo *ai)
 {
        nfs_export *exp;
        nfs_export *found = NULL;
@@ -650,7 +710,7 @@ static nfs_export *lookup_export(char *dom, char *path, struct hostent *he)
 
        for (i=0 ; i < MCL_MAXTYPES; i++) {
                for (exp = exportlist[i].p_head; exp; exp = exp->m_next) {
-                       if (!export_matches(exp, dom, path, he))
+                       if (!export_matches(exp, dom, path, ai))
                                continue;
                        if (!found) {
                                found = exp;
@@ -687,7 +747,7 @@ static nfs_export *lookup_export(char *dom, char *path, struct hostent *he)
        return found;
 }
 
-void nfsd_export(FILE *f)
+static void nfsd_export(FILE *f)
 {
        /* requests are:
         *  domain path
@@ -698,9 +758,7 @@ void nfsd_export(FILE *f)
        char *cp;
        char *dom, *path;
        nfs_export *found = NULL;
-       struct in_addr addr;
-       struct hostent *he = NULL;
-
+       struct addrinfo *ai = NULL;
 
        if (readline(fileno(f), &lbuf, &lbuflen) != 1)
                return;
@@ -722,12 +780,16 @@ void nfsd_export(FILE *f)
        auth_reload();
 
        if (use_ipaddr) {
-               if (!inet_aton(dom, &addr))
+               struct addrinfo *tmp;
+               tmp = host_pton(dom);
+               if (tmp == NULL)
+                       goto out;
+               ai = client_resolve(tmp->ai_addr);
+               freeaddrinfo(tmp);
                        goto out;
-               he = client_resolve(addr);
        }
 
-       found = lookup_export(dom, path, he);
+       found = lookup_export(dom, path, ai);
 
        if (found) {
                if (dump_to_cache(f, dom, path, &found->m_export) < 0) {
@@ -743,7 +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);
 }
 
 
@@ -752,14 +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;
@@ -772,6 +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;
@@ -781,6 +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;
@@ -803,7 +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");
@@ -824,8 +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)
@@ -861,9 +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)
 {
-       struct sockaddr_in *sin = get_addrlist_in(exp->m_client, 0);
+       char buf[INET_ADDRSTRLEN];
        int err;
        FILE *f;
 
@@ -871,8 +951,10 @@ int cache_export(nfs_export *exp, char *path)
        if (!f)
                return -1;
 
+
        qword_print(f, "nfsd");
-       qword_print(f, inet_ntoa(sin->sin_addr));
+       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);
@@ -884,7 +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
@@ -918,4 +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;
 }
-