diff options
Diffstat (limited to 'contrib/openpam/lib/openpam_load.c')
| -rw-r--r-- | contrib/openpam/lib/openpam_load.c | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/contrib/openpam/lib/openpam_load.c b/contrib/openpam/lib/openpam_load.c new file mode 100644 index 0000000..d938959 --- /dev/null +++ b/contrib/openpam/lib/openpam_load.c @@ -0,0 +1,227 @@ +/*- + * Copyright (c) 2002 Networks Associates Technologies, Inc. + * All rights reserved. + * + * This software was developed for the FreeBSD Project by ThinkSec AS and + * NAI Labs, the Security Research Division of Network Associates, Inc. + * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the + * DARPA CHATS research program. + * + * 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. The name of the author may not 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. + * + * $Id$ + */ + +#include <dlfcn.h> +#include <stdlib.h> +#include <string.h> + +#include <security/pam_appl.h> + +#include "openpam_impl.h" + +#ifdef OPENPAM_STATIC_MODULES +SET_DECLARE(_openpam_modules, pam_module_t); +#endif + +const char *_pam_sm_func_name[PAM_NUM_PRIMITIVES] = { + "pam_sm_acct_mgmt", + "pam_sm_authenticate", + "pam_sm_chauthtok", + "pam_sm_close_session", + "pam_sm_open_session", + "pam_sm_setcred" +}; + +static pam_module_t *modules; + +/* + * Load a dynamic module, or locate a static one. Keep a list of + * previously found modules to speed up the process. + */ + +static pam_module_t * +openpam_load_module(const char *path) +{ + pam_module_t *module; + void *dlh; + int i; + + /* check cache first */ + for (module = modules; module != NULL; module = module->next) + if (strcmp(module->path, path) == 0) + goto found; + + /* nope; try to load */ + if ((dlh = dlopen(path, RTLD_NOW)) == NULL) { + openpam_log(PAM_LOG_ERROR, "dlopen(): %s", dlerror()); + } else { + if ((module = calloc(1, sizeof *module)) == NULL) + goto buf_err; + if ((module->path = strdup(path)) == NULL) + goto buf_err; + module->dlh = dlh; + for (i = 0; i < PAM_NUM_PRIMITIVES; ++i) + module->func[i] = dlsym(dlh, _pam_sm_func_name[i]); + } + openpam_log(PAM_LOG_DEBUG, "%s dynamic %s", + (module == NULL) ? "no" : "using", path); + +#ifdef OPENPAM_STATIC_MODULES + /* look for a static module */ + if (module == NULL && strchr(path, '/') == NULL) { + pam_module_t **modp; + + SET_FOREACH(modp, _openpam_modules) { + if (strcmp((*modp)->path, path) == 0) { + module = *modp; + break; + } + } + openpam_log(PAM_LOG_DEBUG, "%s static %s", + (module == NULL) ? "no" : "using", path); + } +#endif + if (module == NULL) + return (NULL); + module->next = modules; + module->prev = NULL; + modules = module; + found: + ++module->refcount; + return (module); + buf_err: + openpam_log(PAM_LOG_ERROR, "malloc(): %m"); + dlclose(dlh); + free(module); + return (NULL); +} + + +/* + * Release a module. + * XXX highly thread-unsafe + */ + +static void +openpam_release_module(pam_module_t *module) +{ + if (module == NULL) + return; + --module->refcount; + if (module->refcount > 0) + /* still in use */ + return; + if (module->refcount < 0) { + openpam_log(PAM_LOG_ERROR, "module %s has negative refcount", + module->path); + module->refcount = 0; + } + if (module->dlh == NULL) + /* static module */ + return; + dlclose(module->dlh); + if (module->prev != NULL) + module->prev->next = module->next; + if (module->next != NULL) + module->next->prev = module->prev; + free(module); +} + + +/* + * Destroy a chain, freeing all its links and releasing the modules + * they point to. + */ + +static void +openpam_destroy_chain(pam_chain_t *chain) +{ + if (chain == NULL) + return; + openpam_destroy_chain(chain->next); + chain->next = NULL; + while (chain->optc--) + free(chain->optv[chain->optc]); + free(chain->optv); + openpam_release_module(chain->module); + free(chain); +} + +/* + * Add a module to a chain. + */ + +int +openpam_add_module(pam_handle_t *pamh, + int chain, + int flag, + const char *modpath, + int optc, + const char *optv[]) +{ + pam_chain_t *new, *iterator; + + if ((new = calloc(1, sizeof *new)) == NULL) + goto buf_err; + if ((new->optv = malloc(sizeof(char *) * (optc + 1))) == NULL) + goto buf_err; + while (optc--) + if ((new->optv[new->optc++] = strdup(*optv++)) == NULL) + goto buf_err; + new->optv[new->optc] = NULL; + new->flag = flag; + if ((new->module = openpam_load_module(modpath)) == NULL) { + openpam_destroy_chain(new); + return (PAM_OPEN_ERR); + } + if ((iterator = pamh->chains[chain]) != NULL) { + while (iterator->next != NULL) + iterator = iterator->next; + iterator->next = new; + } else { + pamh->chains[chain] = new; + } + return (PAM_SUCCESS); + + buf_err: + openpam_log(PAM_LOG_ERROR, "%m"); + openpam_destroy_chain(new); + return (PAM_BUF_ERR); +} + + +/* + * Clear the chains and release the modules + */ + +void +openpam_clear_chains(pam_handle_t *pamh) +{ + int i; + + for (i = 0; i < PAM_NUM_CHAINS; ++i) + openpam_destroy_chain(pamh->chains[i]); +} |
