/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved. * Copyright (c) 2011 Gunnar Beutner * Copyright (c) 2012 Cyril Plisko. All rights reserved. */ #include #include #include #include #include #include #include #include #include #include "libshare_impl.h" static boolean_t nfs_available(void); static sa_fstype_t *nfs_fstype; /* * nfs_exportfs_temp_fd refers to a temporary copy of the output * from exportfs -v. */ static int nfs_exportfs_temp_fd = -1; typedef int (*nfs_shareopt_callback_t)(const char *opt, const char *value, void *cookie); typedef int (*nfs_host_callback_t)(const char *sharepath, const char *host, const char *security, const char *access, void *cookie); /* * Invokes the specified callback function for each Solaris share option * listed in the specified string. */ static int foreach_nfs_shareopt(const char *shareopts, nfs_shareopt_callback_t callback, void *cookie) { char *shareopts_dup, *opt, *cur, *value; int was_nul, rc; if (shareopts == NULL) return (SA_OK); shareopts_dup = strdup(shareopts); if (shareopts_dup == NULL) return (SA_NO_MEMORY); opt = shareopts_dup; was_nul = 0; while (1) { cur = opt; while (*cur != ',' && *cur != '\0') cur++; if (*cur == '\0') was_nul = 1; *cur = '\0'; if (cur > opt) { value = strchr(opt, '='); if (value != NULL) { *value = '\0'; value++; } rc = callback(opt, value, cookie); if (rc != SA_OK) { free(shareopts_dup); return (rc); } } opt = cur + 1; if (was_nul) break; } free(shareopts_dup); return (0); } typedef struct nfs_host_cookie_s { nfs_host_callback_t callback; const char *sharepath; void *cookie; const char *security; } nfs_host_cookie_t; /* * Helper function for foreach_nfs_host. This function checks whether the * current share option is a host specification and invokes a callback * function with information about the host. */ static int foreach_nfs_host_cb(const char *opt, const char *value, void *pcookie) { int rc; const char *access; char *host_dup, *host, *next; nfs_host_cookie_t *udata = (nfs_host_cookie_t *)pcookie; #ifdef DEBUG fprintf(stderr, "foreach_nfs_host_cb: key=%s, value=%s\n", opt, value); #endif if (strcmp(opt, "sec") == 0) udata->security = value; if (strcmp(opt, "rw") == 0 || strcmp(opt, "ro") == 0) { if (value == NULL) value = "*"; access = opt; host_dup = strdup(value); if (host_dup == NULL) return (SA_NO_MEMORY); host = host_dup; do { next = strchr(host, ':'); if (next != NULL) { *next = '\0'; next++; } rc = udata->callback(udata->sharepath, host, udata->security, access, udata->cookie); if (rc != SA_OK) { free(host_dup); return (rc); } host = next; } while (host != NULL); free(host_dup); } return (SA_OK); } /* * Invokes a callback function for all NFS hosts that are set for a share. */ static int foreach_nfs_host(sa_share_impl_t impl_share, nfs_host_callback_t callback, void *cookie) { nfs_host_cookie_t udata; char *shareopts; udata.callback = callback; udata.sharepath = impl_share->sharepath; udata.cookie = cookie; udata.security = "sys"; shareopts = FSINFO(impl_share, nfs_fstype)->shareopts; return foreach_nfs_shareopt(shareopts, foreach_nfs_host_cb, &udata); } /* * Converts a Solaris NFS host specification to its Linux equivalent. */ static int get_linux_hostspec(const char *solaris_hostspec, char **plinux_hostspec) { /* * For now we just support CIDR masks (e.g. @192.168.0.0/16) and host * wildcards (e.g. *.example.org). */ if (solaris_hostspec[0] == '@') { /* * Solaris host specifier, e.g. @192.168.0.0/16; we just need * to skip the @ in this case */ *plinux_hostspec = strdup(solaris_hostspec + 1); } else { *plinux_hostspec = strdup(solaris_hostspec); } if (*plinux_hostspec == NULL) { return (SA_NO_MEMORY); } return (SA_OK); } /* * Used internally by nfs_enable_share to enable sharing for a single host. */ static int nfs_enable_share_one(const char *sharepath, const char *host, const char *security, const char *access, void *pcookie) { int rc; char *linuxhost, *hostpath, *opts; const char *linux_opts = (const char *)pcookie; char *argv[6]; /* exportfs -i -o sec=XX,rX, : */ rc = get_linux_hostspec(host, &linuxhost); if (rc < 0) exit(1); hostpath = malloc(strlen(linuxhost) + 1 + strlen(sharepath) + 1); if (hostpath == NULL) { free(linuxhost); exit(1); } sprintf(hostpath, "%s:%s", linuxhost, sharepath); free(linuxhost); if (linux_opts == NULL) linux_opts = ""; opts = malloc(4 + strlen(security) + 4 + strlen(linux_opts) + 1); if (opts == NULL) exit(1); sprintf(opts, "sec=%s,%s,%s", security, access, linux_opts); #ifdef DEBUG fprintf(stderr, "sharing %s with opts %s\n", hostpath, opts); #endif argv[0] = "/usr/sbin/exportfs"; argv[1] = "-i"; argv[2] = "-o"; argv[3] = opts; argv[4] = hostpath; argv[5] = NULL; rc = libzfs_run_process(argv[0], argv, 0); free(hostpath); free(opts); if (rc < 0) return (SA_SYSTEM_ERR); else return (SA_OK); } /* * Adds a Linux share option to an array of NFS options. */ static int add_linux_shareopt(char **plinux_opts, const char *key, const char *value) { size_t len = 0; char *new_linux_opts; if (*plinux_opts != NULL) len = strlen(*plinux_opts); new_linux_opts = realloc(*plinux_opts, len + 1 + strlen(key) + (value ? 1 + strlen(value) : 0) + 1); if (new_linux_opts == NULL) return (SA_NO_MEMORY); new_linux_opts[len] = '\0'; if (len > 0) strcat(new_linux_opts, ","); strcat(new_linux_opts, key); if (value != NULL) { strcat(new_linux_opts, "="); strcat(new_linux_opts, value); } *plinux_opts = new_linux_opts; return (SA_OK); } /* * Validates and converts a single Solaris share option to its Linux * equivalent. */ static int get_linux_shareopts_cb(const char *key, const char *value, void *cookie) { char **plinux_opts = (char **)cookie; /* host-specific options, these are taken care of elsewhere */ if (strcmp(key, "ro") == 0 || strcmp(key, "rw") == 0 || strcmp(key, "sec") == 0) return (SA_OK); if (strcmp(key, "anon") == 0) key = "anonuid"; if (strcmp(key, "root_mapping") == 0) { (void) add_linux_shareopt(plinux_opts, "root_squash", NULL); key = "anonuid"; } if (strcmp(key, "nosub") == 0) key = "subtree_check"; if (strcmp(key, "insecure") != 0 && strcmp(key, "secure") != 0 && strcmp(key, "async") != 0 && strcmp(key, "sync") != 0 && strcmp(key, "no_wdelay") != 0 && strcmp(key, "wdelay") != 0 && strcmp(key, "nohide") != 0 && strcmp(key, "hide") != 0 && strcmp(key, "crossmnt") != 0 && strcmp(key, "no_subtree_check") != 0 && strcmp(key, "subtree_check") != 0 && strcmp(key, "insecure_locks") != 0 && strcmp(key, "secure_locks") != 0 && strcmp(key, "no_auth_nlm") != 0 && strcmp(key, "auth_nlm") != 0 && strcmp(key, "no_acl") != 0 && strcmp(key, "mountpoint") != 0 && strcmp(key, "mp") != 0 && strcmp(key, "fsuid") != 0 && strcmp(key, "refer") != 0 && strcmp(key, "replicas") != 0 && strcmp(key, "root_squash") != 0 && strcmp(key, "no_root_squash") != 0 && strcmp(key, "all_squash") != 0 && strcmp(key, "no_all_squash") != 0 && strcmp(key, "fsid") != 0 && strcmp(key, "anonuid") != 0 && strcmp(key, "anongid") != 0) { return (SA_SYNTAX_ERR); } (void) add_linux_shareopt(plinux_opts, key, value); return (SA_OK); } /* * Takes a string containing Solaris share options (e.g. "sync,no_acl") and * converts them to a NULL-terminated array of Linux NFS options. */ static int get_linux_shareopts(const char *shareopts, char **plinux_opts) { int rc; assert(plinux_opts != NULL); *plinux_opts = NULL; /* no_subtree_check - Default as of nfs-utils v1.1.0 */ (void) add_linux_shareopt(plinux_opts, "no_subtree_check", NULL); /* mountpoint - Restrict exports to ZFS mountpoints */ (void) add_linux_shareopt(plinux_opts, "mountpoint", NULL); rc = foreach_nfs_shareopt(shareopts, get_linux_shareopts_cb, plinux_opts); if (rc != SA_OK) { free(*plinux_opts); *plinux_opts = NULL; } return (rc); } /* * Enables NFS sharing for the specified share. */ static int nfs_enable_share(sa_share_impl_t impl_share) { char *shareopts, *linux_opts; int rc; if (!nfs_available()) { return (SA_SYSTEM_ERR); } shareopts = FSINFO(impl_share, nfs_fstype)->shareopts; if (shareopts == NULL) return (SA_OK); rc = get_linux_shareopts(shareopts, &linux_opts); if (rc != SA_OK) return (rc); rc = foreach_nfs_host(impl_share, nfs_enable_share_one, linux_opts); free(linux_opts); return (rc); } /* * Used internally by nfs_disable_share to disable sharing for a single host. */ static int nfs_disable_share_one(const char *sharepath, const char *host, const char *security, const char *access, void *cookie) { int rc; char *linuxhost, *hostpath; char *argv[4]; rc = get_linux_hostspec(host, &linuxhost); if (rc < 0) exit(1); hostpath = malloc(strlen(linuxhost) + 1 + strlen(sharepath) + 1); if (hostpath == NULL) { free(linuxhost); exit(1); } sprintf(hostpath, "%s:%s", linuxhost, sharepath); free(linuxhost); #ifdef DEBUG fprintf(stderr, "unsharing %s\n", hostpath); #endif argv[0] = "/usr/sbin/exportfs"; argv[1] = "-u"; argv[2] = hostpath; argv[3] = NULL; rc = libzfs_run_process(argv[0], argv, 0); free(hostpath); if (rc < 0) return (SA_SYSTEM_ERR); else return (SA_OK); } /* * Disables NFS sharing for the specified share. */ static int nfs_disable_share(sa_share_impl_t impl_share) { if (!nfs_available()) { /* * The share can't possibly be active, so nothing * needs to be done to disable it. */ return (SA_OK); } return (foreach_nfs_host(impl_share, nfs_disable_share_one, NULL)); } /* * Checks whether the specified NFS share options are syntactically correct. */ static int nfs_validate_shareopts(const char *shareopts) { char *linux_opts; int rc; rc = get_linux_shareopts(shareopts, &linux_opts); if (rc != SA_OK) return (rc); free(linux_opts); return (SA_OK); } /* * Checks whether a share is currently active. */ static boolean_t nfs_is_share_active(sa_share_impl_t impl_share) { int fd; char line[512]; char *tab, *cur; FILE *nfs_exportfs_temp_fp; if (!nfs_available()) return (B_FALSE); if ((fd = dup(nfs_exportfs_temp_fd)) == -1) return (B_FALSE); nfs_exportfs_temp_fp = fdopen(fd, "r"); if (nfs_exportfs_temp_fp == NULL) return (B_FALSE); if (fseek(nfs_exportfs_temp_fp, 0, SEEK_SET) < 0) { fclose(nfs_exportfs_temp_fp); return (B_FALSE); } while (fgets(line, sizeof (line), nfs_exportfs_temp_fp) != NULL) { /* * exportfs uses separate lines for the share path * and the export options when the share path is longer * than a certain amount of characters; this ignores * the option lines */ if (line[0] == '\t') continue; tab = strchr(line, '\t'); if (tab != NULL) { *tab = '\0'; cur = tab - 1; } else { /* * there's no tab character, which means the * NFS options are on a separate line; we just * need to remove the new-line character * at the end of the line */ cur = line + strlen(line) - 1; } /* remove trailing spaces and new-line characters */ while (cur >= line && (*cur == ' ' || *cur == '\n')) *cur-- = '\0'; if (strcmp(line, impl_share->sharepath) == 0) { fclose(nfs_exportfs_temp_fp); return (B_TRUE); } } fclose(nfs_exportfs_temp_fp); return (B_FALSE); } /* * Called to update a share's options. A share's options might be out of * date if the share was loaded from disk (i.e. /etc/dfs/sharetab) and the * "sharenfs" dataset property has changed in the meantime. This function * also takes care of re-enabling the share if necessary. */ static int nfs_update_shareopts(sa_share_impl_t impl_share, const char *resource, const char *shareopts) { char *shareopts_dup; boolean_t needs_reshare = B_FALSE; char *old_shareopts; FSINFO(impl_share, nfs_fstype)->active = nfs_is_share_active(impl_share); old_shareopts = FSINFO(impl_share, nfs_fstype)->shareopts; if (strcmp(shareopts, "on") == 0) shareopts = "rw,crossmnt"; if (FSINFO(impl_share, nfs_fstype)->active && old_shareopts != NULL && strcmp(old_shareopts, shareopts) != 0) { needs_reshare = B_TRUE; nfs_disable_share(impl_share); } shareopts_dup = strdup(shareopts); if (shareopts_dup == NULL) return (SA_NO_MEMORY); if (old_shareopts != NULL) free(old_shareopts); FSINFO(impl_share, nfs_fstype)->shareopts = shareopts_dup; if (needs_reshare) nfs_enable_share(impl_share); return (SA_OK); } /* * Clears a share's NFS options. Used by libshare to * clean up shares that are about to be free()'d. */ static void nfs_clear_shareopts(sa_share_impl_t impl_share) { free(FSINFO(impl_share, nfs_fstype)->shareopts); FSINFO(impl_share, nfs_fstype)->shareopts = NULL; } static const sa_share_ops_t nfs_shareops = { .enable_share = nfs_enable_share, .disable_share = nfs_disable_share, .validate_shareopts = nfs_validate_shareopts, .update_shareopts = nfs_update_shareopts, .clear_shareopts = nfs_clear_shareopts, }; /* * nfs_check_exportfs() checks that the exportfs command runs * and also maintains a temporary copy of the output from * exportfs -v. * To update this temporary copy simply call this function again. * * TODO : Use /var/lib/nfs/etab instead of our private copy. * But must implement locking to prevent concurrent access. * * TODO : The temporary file descriptor is never closed since * there is no libshare_nfs_fini() function. */ static int nfs_check_exportfs(void) { pid_t pid; int rc, status; static char nfs_exportfs_tempfile[] = "/tmp/exportfs.XXXXXX"; /* * Close any existing temporary copies of output from exportfs. * We have already called unlink() so file will be deleted. */ if (nfs_exportfs_temp_fd >= 0) close(nfs_exportfs_temp_fd); nfs_exportfs_temp_fd = mkstemp(nfs_exportfs_tempfile); if (nfs_exportfs_temp_fd < 0) return (SA_SYSTEM_ERR); unlink(nfs_exportfs_tempfile); (void) fcntl(nfs_exportfs_temp_fd, F_SETFD, FD_CLOEXEC); pid = fork(); if (pid < 0) { (void) close(nfs_exportfs_temp_fd); nfs_exportfs_temp_fd = -1; return (SA_SYSTEM_ERR); } if (pid > 0) { while ((rc = waitpid(pid, &status, 0)) <= 0 && errno == EINTR) { } if (rc <= 0) { (void) close(nfs_exportfs_temp_fd); nfs_exportfs_temp_fd = -1; return (SA_SYSTEM_ERR); } if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) { (void) close(nfs_exportfs_temp_fd); nfs_exportfs_temp_fd = -1; return (SA_CONFIG_ERR); } return (SA_OK); } /* child */ /* exportfs -v */ if (dup2(nfs_exportfs_temp_fd, STDOUT_FILENO) < 0) exit(1); rc = execlp("/usr/sbin/exportfs", "exportfs", "-v", NULL); if (rc < 0) { exit(1); } exit(0); } /* * Provides a convenient wrapper for determining nfs availability */ static boolean_t nfs_available(void) { if (nfs_exportfs_temp_fd == -1) (void) nfs_check_exportfs(); return ((nfs_exportfs_temp_fd != -1) ? B_TRUE : B_FALSE); } /* * Initializes the NFS functionality of libshare. */ void libshare_nfs_init(void) { nfs_fstype = register_fstype("nfs", &nfs_shareops); }