From 6985f3995f74d081cb8f2256a1c6fc2d80166713 Mon Sep 17 00:00:00 2001 From: =?utf8?q?G=C3=BCnther=20Deschner?= Date: Thu, 4 Jun 2009 11:59:32 +0200 Subject: [PATCH] nss_wrapper: add capability to load nss modules. Guenther --- lib/nss_wrapper/nss_wrapper.c | 116 +++++++++++++++++++++++++++++++++- 1 file changed, 115 insertions(+), 1 deletion(-) diff --git a/lib/nss_wrapper/nss_wrapper.c b/lib/nss_wrapper/nss_wrapper.c index cffa04401fb..a2cd0ac52e5 100644 --- a/lib/nss_wrapper/nss_wrapper.c +++ b/lib/nss_wrapper/nss_wrapper.c @@ -37,6 +37,7 @@ #include "../replace/replace.h" #include "system/passwd.h" #include "system/filesys.h" +#include "../nsswitch/nsstest.h" #else /* _SAMBA_BUILD_ */ @@ -139,9 +140,33 @@ #define NWRAP_VERBOSE(args) #endif +struct nwrap_module_nss_fns { + NSS_STATUS (*_nss_getpwnam_r)(const char *name, struct passwd *result, char *buffer, + size_t buflen, int *errnop); + NSS_STATUS (*_nss_getpwuid_r)(uid_t uid, struct passwd *result, char *buffer, + size_t buflen, int *errnop); + NSS_STATUS (*_nss_setpwent)(void); + NSS_STATUS (*_nss_getpwent_r)(struct passwd *result, char *buffer, + size_t buflen, int *errnop); + NSS_STATUS (*_nss_endpwent)(void); + NSS_STATUS (*_nss_initgroups)(const char *user, gid_t group, long int *start, + long int *size, gid_t **groups, long int limit, int *errnop); + NSS_STATUS (*_nss_getgrnam_r)(const char *name, struct group *result, char *buffer, + size_t buflen, int *errnop); + NSS_STATUS (*_nss_getgrgid_r)(gid_t gid, struct group *result, char *buffer, + size_t buflen, int *errnop); + NSS_STATUS (*_nss_setgrent)(void); + NSS_STATUS (*_nss_getgrent_r)(struct group *result, char *buffer, + size_t buflen, int *errnop); + NSS_STATUS (*_nss_endgrent)(void); +}; + struct nwrap_backend { const char *name; + const char *so_path; + void *so_handle; struct nwrap_ops *ops; + struct nwrap_module_nss_fns *fns; }; struct nwrap_ops { @@ -286,8 +311,94 @@ 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_load_module_fn(struct nwrap_backend *b, + const char *fn_name) +{ + void *res; + char *s; + + if (!b->so_handle) { + NWRAP_ERROR(("%s: no handle\n", + __location__)); + return NULL; + } + + if (asprintf(&s, "_nss_%s_%s", b->name, fn_name) == -1) { + NWRAP_ERROR(("%s: out of memory\n", + __location__)); + return NULL; + } + + res = dlsym(b->so_handle, s); + if (!res) { + NWRAP_ERROR(("%s: cannot find function %s in %s\n", + __location__, s, b->so_path)); + } + free(s); + s = NULL; + return res; +} + +static struct nwrap_module_nss_fns *nwrap_load_module_fns(struct nwrap_backend *b) +{ + struct nwrap_module_nss_fns *fns; + + if (!b->so_handle) { + return NULL; + } + + fns = (struct nwrap_module_nss_fns *)malloc(sizeof(struct nwrap_module_nss_fns)); + if (!fns) { + return NULL; + } + + fns->_nss_getpwnam_r = (NSS_STATUS (*)(const char *, struct passwd *, char *, size_t, int *)) + nwrap_load_module_fn(b, "getpwnam_r"); + fns->_nss_getpwuid_r = (NSS_STATUS (*)(uid_t, struct passwd *, char *, size_t, int *)) + nwrap_load_module_fn(b, "getpwuid_r"); + fns->_nss_setpwent = (NSS_STATUS(*)(void)) + nwrap_load_module_fn(b, "setpwent"); + fns->_nss_getpwent_r = (NSS_STATUS (*)(struct passwd *, char *, size_t, int *)) + nwrap_load_module_fn(b, "getpwent_r"); + fns->_nss_endpwent = (NSS_STATUS(*)(void)) + nwrap_load_module_fn(b, "endpwent"); + fns->_nss_initgroups = (NSS_STATUS (*)(const char *, gid_t, long int *, long int *, gid_t **, long int, int *)) + nwrap_load_module_fn(b, "initgroups_dyn"); + fns->_nss_getgrnam_r = (NSS_STATUS (*)(const char *, struct group *, char *, size_t, int *)) + nwrap_load_module_fn(b, "getgrnam_r"); + fns->_nss_getgrgid_r = (NSS_STATUS (*)(gid_t, struct group *, char *, size_t, int *)) + nwrap_load_module_fn(b, "getgrgid_r"); + fns->_nss_setgrent = (NSS_STATUS(*)(void)) + nwrap_load_module_fn(b, "setgrent"); + fns->_nss_getgrent_r = (NSS_STATUS (*)(struct group *, char *, size_t, int *)) + nwrap_load_module_fn(b, "getgrent_r"); + fns->_nss_endgrent = (NSS_STATUS(*)(void)) + nwrap_load_module_fn(b, "endgrent"); + + return fns; +} + +static void *nwrap_load_module(const char *so_path) +{ + void *h; + + if (!so_path || !strlen(so_path)) { + return NULL; + } + + h = dlopen(so_path, RTLD_LAZY); + if (!h) { + NWRAP_ERROR(("%s: cannot open shared library %s\n", + __location__, so_path)); + return NULL; + } + + return h; +} + static bool nwrap_module_init(const char *name, struct nwrap_ops *ops, + const char *so_path, int *num_backends, struct nwrap_backend **backends) { @@ -300,6 +411,9 @@ static bool nwrap_module_init(const char *name, (*backends)[*num_backends].name = name; (*backends)[*num_backends].ops = ops; + (*backends)[*num_backends].so_path = so_path; + (*backends)[*num_backends].so_handle = nwrap_load_module(so_path); + (*backends)[*num_backends].fns = nwrap_load_module_fns(&((*backends)[*num_backends])); (*num_backends)++; @@ -311,7 +425,7 @@ static void nwrap_backend_init(struct nwrap_main *r) r->num_backends = 0; r->backends = NULL; - if (!nwrap_module_init("files", &nwrap_files_ops, + if (!nwrap_module_init("files", &nwrap_files_ops, NULL, &r->num_backends, &r->backends)) { NWRAP_ERROR(("%s: failed to initialize 'files' backend\n", -- 2.34.1