/* * Copyright (C) Stefan Metzmacher 2007 * * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * 3. Neither the name of the author nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #ifdef _SAMBA_BUILD_ #define NSS_WRAPPER_NOT_REPLACE #include "lib/replace/replace.h" #include "system/passwd.h" #include "system/filesys.h" #else /* _SAMBA_BUILD_ */ #error nss_wrapper_only_supported_in_samba_yet #endif #ifndef _PUBLIC_ #define _PUBLIC_ #endif /* LD_PRELOAD doesn't work yet, so REWRITE_CALLS is all we support * for now */ #define REWRITE_CALLS #ifdef REWRITE_CALLS #define real_getpwnam getpwnam #define real_getpwnam_r getpwnam_r #define real_getpwuid getpwuid #define real_getpwuid_r getpwuid_r #define real_setpwent setpwent #define real_getpwent getpwent #define real_getpwent_r getpwent_r #define real_endpwent endpwent /* #define real_getgrlst getgrlst #define real_getgrlst_r getgrlst_r #define real_initgroups_dyn initgroups_dyn */ #define real_initgroups initgroups #define real_getgrnam getgrnam #define real_getgrnam_r getgrnam_r #define real_getgrgid getgrgid #define real_getgrgid_r getgrgid_r #define real_setgrent setgrent #define real_getgrent getgrent #define real_getgrent_r getgrent_r #define real_endgrent endgrent #endif #if 0 # ifdef DEBUG # define NWRAP_ERROR(args) DEBUG(0, args) # else # define NWRAP_ERROR(args) printf args # endif #else #define NWRAP_ERROR(args) #endif #if 0 # ifdef DEBUG # define NWRAP_DEBUG(args) DEBUG(0, args) # else # define NWRAP_DEBUG(args) printf args # endif #else #define NWRAP_DEBUG(args) #endif #if 0 # ifdef DEBUG # define NWRAP_VERBOSE(args) DEBUG(0, args) # else # define NWRAP_VERBOSE(args) printf args # endif #else #define NWRAP_VERBOSE(args) #endif struct nwrap_cache { const char *path; int fd; struct stat st; uint8_t *buf; void *private_data; bool (*parse_line)(struct nwrap_cache *, char *line); void (*unload)(struct nwrap_cache *); }; struct nwrap_pw { struct nwrap_cache *cache; struct passwd *list; int num; int idx; }; struct nwrap_cache __nwrap_cache_pw; struct nwrap_pw nwrap_pw_global; static bool nwrap_pw_parse_line(struct nwrap_cache *nwrap, char *line); static void nwrap_pw_unload(struct nwrap_cache *nwrap); struct nwrap_gr { struct nwrap_cache *cache; struct group *list; int num; int idx; }; struct nwrap_cache __nwrap_cache_gr; struct nwrap_gr nwrap_gr_global; static bool nwrap_gr_parse_line(struct nwrap_cache *nwrap, char *line); static void nwrap_gr_unload(struct nwrap_cache *nwrap); static void nwrap_init(void) { static bool initialized; if (initialized) return; initialized = true; nwrap_pw_global.cache = &__nwrap_cache_pw; nwrap_pw_global.cache->path = getenv("NSS_WRAPPER_PASSWD"); nwrap_pw_global.cache->fd = -1; nwrap_pw_global.cache->private_data = &nwrap_pw_global; nwrap_pw_global.cache->parse_line = nwrap_pw_parse_line; nwrap_pw_global.cache->unload = nwrap_pw_unload; nwrap_gr_global.cache = &__nwrap_cache_gr; nwrap_gr_global.cache->path = getenv("NSS_WRAPPER_GROUP"); nwrap_gr_global.cache->fd = -1; nwrap_gr_global.cache->private_data = &nwrap_gr_global; nwrap_gr_global.cache->parse_line = nwrap_gr_parse_line; nwrap_gr_global.cache->unload = nwrap_gr_unload; } static bool nwrap_enabled(void) { nwrap_init(); if (!nwrap_pw_global.cache->path) { return false; } if (nwrap_pw_global.cache->path[0] == '\0') { return false; } if (!nwrap_gr_global.cache->path) { return false; } if (nwrap_gr_global.cache->path[0] == '\0') { return false; } return true; } static bool nwrap_parse_file(struct nwrap_cache *nwrap) { int ret; uint8_t *buf = NULL; char *nline; if (nwrap->st.st_size == 0) { NWRAP_DEBUG(("%s: size == 0\n", __location__)); goto done; } if (nwrap->st.st_size > INT32_MAX) { NWRAP_ERROR(("%s: size[%u] larger than INT32_MAX\n", __location__, (unsigned)nwrap->st.st_size)); goto failed; } ret = lseek(nwrap->fd, 0, SEEK_SET); if (ret != 0) { NWRAP_ERROR(("%s: lseek - %d\n",__location__,ret)); goto failed; } buf = malloc(nwrap->st.st_size + 1); if (!buf) { NWRAP_ERROR(("%s: malloc failed\n",__location__)); goto failed; } ret = read(nwrap->fd, buf, nwrap->st.st_size); if (ret != nwrap->st.st_size) { NWRAP_ERROR(("%s: read(%u) gave %d\n", __location__, (unsigned)nwrap->st.st_size, ret)); goto failed; } buf[nwrap->st.st_size] = '\0'; nline = (char *)buf; while (nline && nline[0]) { char *line; char *e; bool ok; line = nline; nline = NULL; e = strchr(line, '\n'); if (e) { e[0] = '\0'; e++; if (e[0] == '\r') { e[0] = '\0'; e++; } nline = e; } NWRAP_VERBOSE(("%s:'%s'\n",__location__, line)); if (strlen(line) == 0) { continue; } ok = nwrap->parse_line(nwrap, line); if (!ok) { goto failed; } } done: nwrap->buf = buf; return true; failed: if (buf) free(buf); return false; } static void nwrap_cache_unload(struct nwrap_cache *nwrap) { nwrap->unload(nwrap); if (nwrap->buf) free(nwrap->buf); nwrap->buf = NULL; } static void nwrap_cache_reload(struct nwrap_cache *nwrap) { struct stat st; int ret; bool ok; bool retried = false; reopen: if (nwrap->fd < 0) { nwrap->fd = open(nwrap->path, O_RDONLY); if (nwrap->fd < 0) { NWRAP_ERROR(("%s: unable to open '%s' readonly %d:%s\n", __location__, nwrap->path, nwrap->fd, strerror(errno))); return; } NWRAP_VERBOSE(("%s: open '%s'\n", __location__, nwrap->path)); } ret = fstat(nwrap->fd, &st); if (ret != 0) { NWRAP_ERROR(("%s: fstat(%s) - %d:%s\n", __location__, nwrap->path, ret, strerror(errno))); return; } if (retried == false && st.st_nlink == 0) { /* maybe someone has replaced the file... */ NWRAP_DEBUG(("%s: st_nlink == 0, reopen %s\n", __location__, nwrap->path)); retried = true; memset(&nwrap->st, 0, sizeof(nwrap->st)); close(nwrap->fd); nwrap->fd = -1; goto reopen; } if (st.st_mtime == nwrap->st.st_mtime) { NWRAP_VERBOSE(("%s: st_mtime[%u] hasn't changed, skip reload\n", __location__, (unsigned)st.st_mtime)); return; } NWRAP_DEBUG(("%s: st_mtime has changed [%u] => [%u], start reload\n", __location__, (unsigned)st.st_mtime, (unsigned)nwrap->st.st_mtime)); nwrap->st = st; nwrap_cache_unload(nwrap); ok = nwrap_parse_file(nwrap); if (!ok) { NWRAP_ERROR(("%s: failed to reload %s\n", __location__, nwrap->path)); nwrap_cache_unload(nwrap); } NWRAP_DEBUG(("%s: reloaded %s\n", __location__, nwrap->path)); } /* * the caller has to call nwrap_unload() on failure */ static bool nwrap_pw_parse_line(struct nwrap_cache *nwrap, char *line) { struct nwrap_pw *nwrap_pw; char *c; char *p; char *e; struct passwd *pw; size_t list_size; nwrap_pw = (struct nwrap_pw *)nwrap->private_data; list_size = sizeof(*nwrap_pw->list) * (nwrap_pw->num+1); pw = (struct passwd *)realloc(nwrap_pw->list, list_size); if (!pw) { NWRAP_ERROR(("%s:realloc(%u) failed\n", __location__, list_size)); return false; } nwrap_pw->list = pw; pw = &nwrap_pw->list[nwrap_pw->num]; c = line; /* name */ p = strchr(c, ':'); if (!p) { NWRAP_ERROR(("%s:invalid line[%s]: '%s'\n", __location__, line, c)); return false; } *p = '\0'; p++; pw->pw_name = c; c = p; NWRAP_VERBOSE(("name[%s]\n", pw->pw_name)); /* password */ p = strchr(c, ':'); if (!p) { NWRAP_ERROR(("%s:invalid line[%s]: '%s'\n", __location__, line, c)); return false; } *p = '\0'; p++; pw->pw_passwd = c; c = p; NWRAP_VERBOSE(("password[%s]\n", pw->pw_passwd)); /* uid */ p = strchr(c, ':'); if (!p) { NWRAP_ERROR(("%s:invalid line[%s]: '%s'\n", __location__, line, c)); return false; } *p = '\0'; p++; e = NULL; pw->pw_uid = (uid_t)strtoul(c, &e, 10); if (c == e) { NWRAP_ERROR(("%s:invalid line[%s]: '%s' - %s\n", __location__, line, c, strerror(errno))); return false; } if (e == NULL) { NWRAP_ERROR(("%s:invalid line[%s]: '%s' - %s\n", __location__, line, c, strerror(errno))); return false; } if (e[0] != '\0') { NWRAP_ERROR(("%s:invalid line[%s]: '%s' - %s\n", __location__, line, c, strerror(errno))); return false; } c = p; NWRAP_VERBOSE(("uid[%u]\n", pw->pw_uid)); /* gid */ p = strchr(c, ':'); if (!p) { NWRAP_ERROR(("%s:invalid line[%s]: '%s'\n", __location__, line, c)); return false; } *p = '\0'; p++; e = NULL; pw->pw_gid = (gid_t)strtoul(c, &e, 10); if (c == e) { NWRAP_ERROR(("%s:invalid line[%s]: '%s' - %s\n", __location__, line, c, strerror(errno))); return false; } if (e == NULL) { NWRAP_ERROR(("%s:invalid line[%s]: '%s' - %s\n", __location__, line, c, strerror(errno))); return false; } if (e[0] != '\0') { NWRAP_ERROR(("%s:invalid line[%s]: '%s' - %s\n", __location__, line, c, strerror(errno))); return false; } c = p; NWRAP_VERBOSE(("gid[%u]\n", pw->pw_gid)); /* gecos */ p = strchr(c, ':'); if (!p) { NWRAP_ERROR(("%s:invalid line[%s]: '%s'\n", __location__, line, c)); return false; } *p = '\0'; p++; pw->pw_gecos = c; c = p; NWRAP_VERBOSE(("gecos[%s]\n", pw->pw_gecos)); /* dir */ p = strchr(c, ':'); if (!p) { NWRAP_ERROR(("%s:'%s'\n",__location__,c)); return false; } *p = '\0'; p++; pw->pw_dir = c; c = p; NWRAP_VERBOSE(("dir[%s]\n", pw->pw_dir)); /* shell */ pw->pw_shell = c; NWRAP_VERBOSE(("shell[%s]\n", pw->pw_shell)); NWRAP_DEBUG(("add user[%s:%s:%u:%u:%s:%s:%s]\n", pw->pw_name, pw->pw_passwd, pw->pw_uid, pw->pw_gid, pw->pw_gecos, pw->pw_dir, pw->pw_shell)); nwrap_pw->num++; return true; } static void nwrap_pw_unload(struct nwrap_cache *nwrap) { struct nwrap_pw *nwrap_pw; nwrap_pw = (struct nwrap_pw *)nwrap->private_data; if (nwrap_pw->list) free(nwrap_pw->list); nwrap_pw->list = NULL; nwrap_pw->num = 0; nwrap_pw->idx = 0; } static int nwrap_pw_copy_r(const struct passwd *src, struct passwd *dst, char *buf, size_t buflen, struct passwd **destp) { char *first; char *last; off_t ofs; first = src->pw_name; last = src->pw_shell; while (*last) last++; ofs = PTR_DIFF(last + 1, first); if (ofs > buflen) { return ERANGE; } memcpy(buf, first, ofs); ofs = PTR_DIFF(src->pw_name, first); dst->pw_name = buf + ofs; ofs = PTR_DIFF(src->pw_passwd, first); dst->pw_passwd = buf + ofs; dst->pw_uid = src->pw_uid; dst->pw_gid = src->pw_gid; ofs = PTR_DIFF(src->pw_gecos, first); dst->pw_gecos = buf + ofs; ofs = PTR_DIFF(src->pw_dir, first); dst->pw_dir = buf + ofs; ofs = PTR_DIFF(src->pw_shell, first); dst->pw_shell = buf + ofs; return 0; } /* * the caller has to call nwrap_unload() on failure */ static bool nwrap_gr_parse_line(struct nwrap_cache *nwrap, char *line) { struct nwrap_gr *nwrap_gr; char *c; char *p; char *e; struct group *gr; size_t list_size; unsigned nummem; nwrap_gr = (struct nwrap_gr *)nwrap->private_data; list_size = sizeof(*nwrap_gr->list) * (nwrap_gr->num+1); gr = (struct group *)realloc(nwrap_gr->list, list_size); if (!gr) { NWRAP_ERROR(("%s:realloc failed\n",__location__)); return false; } nwrap_gr->list = gr; gr = &nwrap_gr->list[nwrap_gr->num]; c = line; /* name */ p = strchr(c, ':'); if (!p) { NWRAP_ERROR(("%s:invalid line[%s]: '%s'\n", __location__, line, c)); return false; } *p = '\0'; p++; gr->gr_name = c; c = p; NWRAP_VERBOSE(("name[%s]\n", gr->gr_name)); /* password */ p = strchr(c, ':'); if (!p) { NWRAP_ERROR(("%s:invalid line[%s]: '%s'\n", __location__, line, c)); return false; } *p = '\0'; p++; gr->gr_passwd = c; c = p; NWRAP_VERBOSE(("password[%s]\n", gr->gr_passwd)); /* gid */ p = strchr(c, ':'); if (!p) { NWRAP_ERROR(("%s:invalid line[%s]: '%s'\n", __location__, line, c)); return false; } *p = '\0'; p++; e = NULL; gr->gr_gid = (gid_t)strtoul(c, &e, 10); if (c == e) { NWRAP_ERROR(("%s:invalid line[%s]: '%s' - %s\n", __location__, line, c, strerror(errno))); return false; } if (e == NULL) { NWRAP_ERROR(("%s:invalid line[%s]: '%s' - %s\n", __location__, line, c, strerror(errno))); return false; } if (e[0] != '\0') { NWRAP_ERROR(("%s:invalid line[%s]: '%s' - %s\n", __location__, line, c, strerror(errno))); return false; } c = p; NWRAP_VERBOSE(("gid[%u]\n", gr->gr_gid)); /* members */ gr->gr_mem = (char **)malloc(sizeof(char *)); if (!gr->gr_mem) { NWRAP_ERROR(("%s:calloc failed\n",__location__)); return false; } gr->gr_mem[0] = NULL; for(nummem=0; p; nummem++) { char **m; size_t m_size; c = p; p = strchr(c, ','); if (p) { *p = '\0'; p++; } if (strlen(c) == 0) { break; } m_size = sizeof(char *) * (nummem+2); m = (char **)realloc(gr->gr_mem, m_size); if (!m) { NWRAP_ERROR(("%s:realloc(%u) failed\n", __location__, m_size)); return false; } gr->gr_mem = m; gr->gr_mem[nummem] = c; gr->gr_mem[nummem+1] = NULL; NWRAP_VERBOSE(("member[%u]: '%s'\n", nummem, gr->gr_mem[nummem])); } NWRAP_DEBUG(("add group[%s:%s:%u:] with %u members\n", gr->gr_name, gr->gr_passwd, gr->gr_gid, nummem)); nwrap_gr->num++; return true; } static void nwrap_gr_unload(struct nwrap_cache *nwrap) { int i; struct nwrap_gr *nwrap_gr; nwrap_gr = (struct nwrap_gr *)nwrap->private_data; if (nwrap_gr->list) { for (i=0; i < nwrap_gr->num; i++) { if (nwrap_gr->list[i].gr_mem) { free(nwrap_gr->list[i].gr_mem); } } free(nwrap_gr->list); } nwrap_gr->list = NULL; nwrap_gr->num = 0; nwrap_gr->idx = 0; } static int nwrap_gr_copy_r(const struct group *src, struct group *dst, char *buf, size_t buflen, struct group **destp) { char *first; char **lastm; char *last; off_t ofsb; off_t ofsm; off_t ofs; unsigned i; first = src->gr_name; lastm = src->gr_mem; while (*lastm) lastm++; last = *lastm; while (*last) last++; ofsb = PTR_DIFF(last + 1, first); ofsm = PTR_DIFF(lastm + 1, src->gr_mem); if ((ofsb + ofsm) > buflen) { return ERANGE; } memcpy(buf, first, ofsb); memcpy(buf + ofsb, src->gr_mem, ofsm); ofs = PTR_DIFF(src->gr_name, first); dst->gr_name = buf + ofs; ofs = PTR_DIFF(src->gr_passwd, first); dst->gr_passwd = buf + ofs; dst->gr_gid = src->gr_gid; dst->gr_mem = (char **)(buf + ofsb); for (i=0; src->gr_mem[i]; i++) { ofs = PTR_DIFF(src->gr_mem[i], first); dst->gr_mem[i] = buf + ofs; } return 0; } /* user functions */ _PUBLIC_ struct passwd *nwrap_getpwnam(const char *name) { int i; if (!nwrap_enabled()) { return real_getpwnam(name); } nwrap_cache_reload(nwrap_pw_global.cache); for (i=0; i= nwrap_pw_global.num) { errno = ENOENT; return NULL; } pw = &nwrap_pw_global.list[nwrap_pw_global.idx++]; NWRAP_VERBOSE(("%s: return user[%s] uid[%u]\n", __location__, pw->pw_name, pw->pw_uid)); return pw; } _PUBLIC_ int nwrap_getpwent_r(struct passwd *pwdst, char *buf, size_t buflen, struct passwd **pwdstp) { struct passwd *pw; if (!nwrap_enabled()) { return real_getpwent_r(pwdst, buf, buflen, pwdstp); } pw = nwrap_getpwent(); if (!pw) { if (errno == 0) { return ENOENT; } return errno; } return nwrap_pw_copy_r(pw, pwdst, buf, buflen, pwdstp); } _PUBLIC_ void nwrap_endpwent(void) { if (!nwrap_enabled()) { real_endpwent(); } nwrap_pw_global.idx = 0; } /* misc functions */ _PUBLIC_ int nwrap_initgroups(const char *user, gid_t group) { if (!nwrap_enabled()) { return real_initgroups(user, group); } /* TODO: maybe we should also fake this... */ return EPERM; } /* group functions */ _PUBLIC_ struct group *nwrap_getgrnam(const char *name) { int i; if (!nwrap_enabled()) { return real_getgrnam(name); } nwrap_cache_reload(nwrap_gr_global.cache); for (i=0; i= nwrap_gr_global.num) { errno = ENOENT; return NULL; } gr = &nwrap_gr_global.list[nwrap_gr_global.idx++]; NWRAP_VERBOSE(("%s: return group[%s] gid[%u]\n", __location__, gr->gr_name, gr->gr_gid)); return gr; } _PUBLIC_ int nwrap_getgrent_r(struct group *grdst, char *buf, size_t buflen, struct group **grdstp) { struct group *gr; if (!nwrap_enabled()) { return real_getgrent_r(grdst, buf, buflen, grdstp); } gr = nwrap_getgrent(); if (!gr) { if (errno == 0) { return ENOENT; } return errno; } return nwrap_gr_copy_r(gr, grdst, buf, buflen, grdstp); } _PUBLIC_ void nwrap_endgrent(void) { if (!nwrap_enabled()) { real_endgrent(); } nwrap_gr_global.idx = 0; }