From 8daa83a594a2e98f39d764422bfbdbc62c9efd44 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Fri, 19 Apr 2024 19:20:00 +0200 Subject: Adding upstream version 2:4.20.0+dfsg. Signed-off-by: Daniel Baumann --- lib/util/modules.c | 320 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 320 insertions(+) create mode 100644 lib/util/modules.c (limited to 'lib/util/modules.c') diff --git a/lib/util/modules.c b/lib/util/modules.c new file mode 100644 index 0000000..4260234 --- /dev/null +++ b/lib/util/modules.c @@ -0,0 +1,320 @@ +/* + Unix SMB/CIFS implementation. + Samba utility functions + Copyright (C) Jelmer Vernooij 2002-2003,2005-2007 + Copyright (C) Stefan (metze) Metzmacher 2003 + Copyright (C) Andrew Bartlett 2011 + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . +*/ + +#include "includes.h" +#include "dynconfig/dynconfig.h" +#include "lib/util/samba_modules.h" +#include "lib/util/util_paths.h" +#include "system/filesys.h" +#include "system/dir.h" + +/** + * Obtain the init function from a shared library file + */ +init_module_fn load_module(const char *path, bool is_probe, void **handle_out) +{ + void *handle; + void *init_fn; + char *error; + + /* This should be a WAF build, where modules should be built + * with no undefined symbols and are already linked against + * the libraries that they are loaded by */ + handle = dlopen(path, RTLD_NOW); + + /* This call should reset any possible non-fatal errors that + occurred since last call to dl* functions */ + error = dlerror(); + + if (handle == NULL) { + int level = is_probe ? 5 : 0; + DEBUG(level, ("Error loading module '%s': %s\n", path, error ? error : "")); + return NULL; + } + + init_fn = (init_module_fn)dlsym(handle, SAMBA_INIT_MODULE); + + /* we could check dlerror() to determine if it worked, because + dlsym() can validly return NULL, but what would we do with + a NULL pointer as a module init function? */ + + if (init_fn == NULL) { + DEBUG(0, ("Unable to find %s() in %s: %s\n", + SAMBA_INIT_MODULE, path, dlerror())); + DEBUG(1, ("Loading module '%s' failed\n", path)); + dlclose(handle); + return NULL; + } + + if (handle_out) { + *handle_out = handle; + } + + return (init_module_fn)init_fn; +} + +/** + * Obtain list of init functions from the modules in the specified + * directory + */ +static init_module_fn *load_modules(TALLOC_CTX *mem_ctx, const char *path) +{ + DIR *dir; + struct dirent *entry; + char *filename; + int success = 0; + init_module_fn *ret = talloc_array(mem_ctx, init_module_fn, 2); + + ret[0] = NULL; + + dir = opendir(path); + if (dir == NULL) { + talloc_free(ret); + return NULL; + } + + while((entry = readdir(dir))) { + if (ISDOT(entry->d_name) || ISDOTDOT(entry->d_name)) + continue; + + filename = talloc_asprintf(mem_ctx, "%s/%s", path, entry->d_name); + + ret[success] = load_module(filename, true, NULL); + if (ret[success]) { + ret = talloc_realloc(mem_ctx, ret, init_module_fn, success+2); + success++; + ret[success] = NULL; + } + + talloc_free(filename); + } + + closedir(dir); + + return ret; +} + +/** + * Run the specified init functions. + * + * @return true if all functions ran successfully, false otherwise + */ +bool run_init_functions(TALLOC_CTX *ctx, init_module_fn *fns) +{ + int i; + bool ret = true; + + if (fns == NULL) + return true; + + for (i = 0; fns[i]; i++) { ret &= (bool)NT_STATUS_IS_OK(fns[i](ctx)); } + + return ret; +} + +/** + * Load the initialization functions from DSO files for a specific subsystem. + * + * Will return an array of function pointers to initialization functions + */ + +init_module_fn *load_samba_modules(TALLOC_CTX *mem_ctx, const char *subsystem) +{ + char *path = modules_path(mem_ctx, subsystem); + init_module_fn *ret; + + ret = load_modules(mem_ctx, path); + + talloc_free(path); + + return ret; +} + +static NTSTATUS load_module_absolute_path(const char *module_path, + bool is_probe) +{ + void *handle; + init_module_fn init; + NTSTATUS status; + + DBG_INFO("%s module '%s'\n", + is_probe ? "Probing" : "Loading", + module_path); + + init = load_module(module_path, is_probe, &handle); + if (init == NULL) { + return NT_STATUS_UNSUCCESSFUL; + } + + DBG_NOTICE("Module '%s' loaded\n", module_path); + + status = init(NULL); + if (!NT_STATUS_IS_OK(status)) { + DBG_ERR("Module '%s' initialization failed: %s\n", + module_path, + get_friendly_nt_error_msg(status)); + dlclose(handle); + return status; + } + + return NT_STATUS_OK; +} + +/* Load all modules in list and return number of + * modules that has been successfully loaded */ +int smb_load_all_modules_absoute_path(const char **modules) +{ + int i; + int success = 0; + + for(i = 0; modules[i] != NULL; i++) { + const char *module = modules[i]; + NTSTATUS status; + + if (module[0] != '/') { + continue; + } + + status = load_module_absolute_path(module, false); + if (NT_STATUS_IS_OK(status)) { + success++; + } + } + + DEBUG(2, ("%d modules successfully loaded\n", success)); + + return success; +} + +/** + * @brief Check if a module exist and load it. + * + * @param[in] subsystem The name of the subsystem the module belongs too. + * + * @param[in] module The name of the module + * + * @return A NTSTATUS code + */ +NTSTATUS smb_probe_module(const char *subsystem, const char *module) +{ + NTSTATUS status; + char *module_path = NULL; + TALLOC_CTX *tmp_ctx = talloc_stackframe(); + + if (subsystem == NULL) { + status = NT_STATUS_INVALID_PARAMETER; + goto done; + } + if (module == NULL) { + status = NT_STATUS_INVALID_PARAMETER; + goto done; + } + + if (strchr(module, '/')) { + status = NT_STATUS_INVALID_PARAMETER; + goto done; + } + + module_path = talloc_asprintf(tmp_ctx, + "%s/%s.%s", + modules_path(tmp_ctx, subsystem), + module, + shlib_ext()); + if (module_path == NULL) { + status = NT_STATUS_NO_MEMORY; + goto done; + } + + status = load_module_absolute_path(module_path, true); + +done: + TALLOC_FREE(tmp_ctx); + return status; +} + +/** + * @brief Check if a module exist and load it. + * + * Warning: Using this function can have security implecations! + * + * @param[in] subsystem The name of the subsystem the module belongs too. + * + * @param[in] module Load a module using an absolute path. + * + * @return A NTSTATUS code + */ +NTSTATUS smb_probe_module_absolute_path(const char *module) +{ + if (module == NULL) { + return NT_STATUS_INVALID_PARAMETER; + } + if (module[0] != '/') { + return NT_STATUS_INVALID_PARAMETER; + } + + return load_module_absolute_path(module, true); +} + +/** + * @brief Load a module. + * + * @param[in] subsystem The name of the subsystem the module belongs too. + * + * @param[in] module Check if a module exists and load it. + * + * @return A NTSTATUS code + */ +NTSTATUS smb_load_module(const char *subsystem, const char *module) +{ + NTSTATUS status; + char *module_path = NULL; + TALLOC_CTX *tmp_ctx = talloc_stackframe(); + + if (subsystem == NULL) { + status = NT_STATUS_INVALID_PARAMETER; + goto done; + } + if (module == NULL) { + status = NT_STATUS_INVALID_PARAMETER; + goto done; + } + + if (strchr(module, '/')) { + status = NT_STATUS_INVALID_PARAMETER; + goto done; + } + + module_path = talloc_asprintf(tmp_ctx, + "%s/%s.%s", + modules_path(tmp_ctx, subsystem), + module, + shlib_ext()); + if (module_path == NULL) { + status = NT_STATUS_NO_MEMORY; + goto done; + } + + status = load_module_absolute_path(module_path, false); + +done: + TALLOC_FREE(tmp_ctx); + return status; +} -- cgit v1.2.3