diff options
Diffstat (limited to 'support/export/v4root.c')
| -rw-r--r-- | support/export/v4root.c | 233 |
1 files changed, 233 insertions, 0 deletions
diff --git a/support/export/v4root.c b/support/export/v4root.c new file mode 100644 index 0000000..03805dc --- /dev/null +++ b/support/export/v4root.c @@ -0,0 +1,233 @@ +/* + * Copyright (C) 2009 Red Hat <nfs@redhat.com> + * + * support/export/v4root.c + * + * Routines used to support NFSv4 pseudo roots + * + */ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#include <sys/types.h> +#include <sys/stat.h> +#include <sys/queue.h> +#include <stdio.h> +#include <stdlib.h> +#include <ctype.h> + +#include <unistd.h> +#include <errno.h> +#include <uuid/uuid.h> + +#include "xlog.h" +#include "exportfs.h" +#include "nfslib.h" +#include "misc.h" +#include "v4root.h" +#include "pseudoflavors.h" + +static nfs_export pseudo_root = { + .m_next = NULL, + .m_client = NULL, + .m_export = { + .e_hostname = "*", + .e_path = "/", + .e_flags = NFSEXP_READONLY + | NFSEXP_NOSUBTREECHECK | NFSEXP_FSID + | NFSEXP_V4ROOT | NFSEXP_INSECURE_PORT, + .e_anonuid = 65534, + .e_anongid = 65534, + .e_squids = NULL, + .e_nsquids = 0, + .e_sqgids = NULL, + .e_nsqgids = 0, + .e_fsid = 0, + .e_mountpoint = NULL, + .e_ttl = 0, + }, + .m_exported = 0, + .m_xtabent = 1, + .m_mayexport = 1, + .m_changed = 0, + .m_warned = 0, +}; + +static void +set_pseudofs_security(struct exportent *pseudo) +{ + struct flav_info *flav; + int i; + + for (flav = flav_map; flav < flav_map + flav_map_size; flav++) { + struct sec_entry *new; + + if (!flav->fnum) + continue; + if (flav->need_krb5 && access("/etc/krb5.keytab", F_OK) != 0) + continue; + + i = secinfo_addflavor(flav, pseudo); + new = &pseudo->e_secinfo[i]; + + new->flags |= NFSEXP_INSECURE_PORT; + } +} + +/* + * Create a pseudo export + */ +static struct exportent * +v4root_create(char *path, nfs_export *export) +{ + nfs_export *exp; + struct exportent eep; + struct exportent *curexp = &export->m_export; + + dupexportent(&eep, &pseudo_root.m_export); + eep.e_ttl = default_ttl; + eep.e_hostname = curexp->e_hostname; + strncpy(eep.e_path, path, sizeof(eep.e_path)-1); + if (strcmp(path, "/") != 0) + eep.e_flags &= ~NFSEXP_FSID; + + if (strcmp(path, "/") != 0 && + !export_test(&eep, 0)) { + /* Need a uuid - base it on path using a fixed seed that + * was generated randomly. + */ + const char seed_s[] = "39c6b5c1-3f24-4f4e-977c-7fe6546b8a25"; + uuid_t seed, uuid; + char uuid_s[UUID_STR_LEN]; + unsigned int i, j; + + uuid_parse(seed_s, seed); + uuid_generate_sha1(uuid, seed, path, strlen(path)); + uuid_unparse_upper(uuid, uuid_s); + /* strip hyhens */ + for (i = j = 0; uuid_s[i]; i++) + if (uuid_s[i] != '-') + uuid_s[j++] = uuid_s[i]; + eep.e_uuid = uuid_s; + } + set_pseudofs_security(&eep); + exp = export_create(&eep, 0); + if (exp == NULL) + return NULL; + xlog(D_CALL, "v4root_create: path '%s' flags 0x%x", + exp->m_export.e_path, exp->m_export.e_flags); + return &exp->m_export; +} + +/* + * Make sure the kernel has pseudo root support. + */ +static int +v4root_support(void) +{ + struct export_features *ef; + static int warned = 0; + + ef = get_export_features(); + + if (ef->flags & NFSEXP_V4ROOT) + return 1; + if (!warned) { + xlog(L_WARNING, "Kernel does not have pseudo root support."); + xlog(L_WARNING, "NFS v4 mounts will be disabled unless fsid=0"); + xlog(L_WARNING, "is specfied in /etc/exports file."); + warned++; + } + return 0; +} + +static int +pseudofs_update(char *hostname, char *path, nfs_export *source) +{ + nfs_export *exp; + + exp = export_lookup(hostname, path, 0); + if (exp && !(exp->m_export.e_flags & NFSEXP_V4ROOT)) + return 0; + if (!exp) { + if (v4root_create(path, source) == NULL) { + xlog(L_WARNING, "v4root_set: Unable to create " + "pseudo export for '%s'", path); + return -ENOMEM; + } + return 0; + } + /* Update an existing V4ROOT export: */ + set_pseudofs_security(&exp->m_export); + return 0; +} + +static int v4root_add_parents(nfs_export *exp) +{ + char *hostname = exp->m_export.e_hostname; + char *path; + char *ptr; + int ret = 0; + + path = strdup(exp->m_export.e_path); + if (!path) { + xlog(L_WARNING, "v4root_add_parents: Unable to create " + "pseudo export for '%s'", exp->m_export.e_path); + return -ENOMEM; + } + for (ptr = path; ptr; ptr = strchr(ptr, '/')) { + char saved; + + saved = *ptr; + *ptr = '\0'; + ret = pseudofs_update(hostname, *path ? path : "/", exp); + if (ret) + break; + *ptr = saved; + ptr++; + } + free(path); + return ret; +} + +/* + * Create pseudo exports by running through the real export + * looking at the components of the path that make up the export. + * Those path components, if not exported, will become pseudo + * exports allowing them to be found when the kernel does an upcall + * looking for components of the v4 mount. + */ +void +v4root_set(void) +{ + nfs_export *exp; + int i; + + if (!v4root_needed) + return; + if (!v4root_support()) + return; + + for (i = 0; i < MCL_MAXTYPES; i++) { + for (exp = exportlist[i].p_head; exp; exp = exp->m_next) { + if (exp->m_export.e_flags & NFSEXP_V4ROOT) + /* + * We just added this one, so its + * parents are already dealt with! + */ + continue; + + if (strcmp(exp->m_export.e_path, "/") == 0 && + !(exp->m_export.e_flags & NFSEXP_FSID)) { + /* Force '/' to be exported as fsid == 0*/ + exp->m_export.e_flags |= NFSEXP_FSID; + exp->m_export.e_fsid = 0; + } + + v4root_add_parents(exp); + /* XXX: error handling! */ + } + } +} |