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Diffstat (limited to '')
| -rw-r--r-- | libpam/pam_handlers.c | 1045 |
1 files changed, 1045 insertions, 0 deletions
diff --git a/libpam/pam_handlers.c b/libpam/pam_handlers.c new file mode 100644 index 0000000..ffa5e4a --- /dev/null +++ b/libpam/pam_handlers.c @@ -0,0 +1,1045 @@ +/* pam_handlers.c -- pam config file parsing and module loading */ + +/* + * created by Marc Ewing. + * Currently maintained by Andrew G. Morgan <morgan@kernel.org> + * + */ + +#include "pam_private.h" +#include "pam_inline.h" + +#include <stdlib.h> +#include <stdio.h> +#include <string.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <unistd.h> + +#define BUF_SIZE 1024 +#define MODULE_CHUNK 4 +#define UNKNOWN_MODULE "<*unknown module*>" +#ifndef _PAM_ISA +#define _PAM_ISA "." +#endif + +static int _pam_assemble_line(FILE *f, char *buf, int buf_len); + +static void _pam_free_handlers_aux(struct handler **hp); + +static int _pam_add_handler(pam_handle_t *pamh + , int must_fail, int other, int stack_level, int type + , int *actions, const char *mod_path + , int argc, char **argv, int argvlen); + +/* Values for module type */ + +#define PAM_T_ANY 0 +#define PAM_T_AUTH 1 +#define PAM_T_SESS 2 +#define PAM_T_ACCT 4 +#define PAM_T_PASS 8 + +static int _pam_load_conf_file(pam_handle_t *pamh, const char *config_name + , const char *service /* specific file */ + , int module_type /* specific type */ + , int stack_level /* level of substack */ +#ifdef PAM_READ_BOTH_CONFS + , int not_other +#endif /* PAM_READ_BOTH_CONFS */ + ); + +static int _pam_parse_conf_file(pam_handle_t *pamh, FILE *f + , const char *known_service /* specific file */ + , int requested_module_type /* specific type */ + , int stack_level /* level of substack */ +#ifdef PAM_READ_BOTH_CONFS + , int not_other +#endif /* PAM_READ_BOTH_CONFS */ + ) +{ + char buf[BUF_SIZE]; + int x; /* read a line from the FILE *f ? */ + /* + * read a line from the configuration (FILE *) f + */ + while ((x = _pam_assemble_line(f, buf, BUF_SIZE)) > 0) { + char *tok, *nexttok=NULL; + const char *this_service; + const char *mod_path; + int module_type, actions[_PAM_RETURN_VALUES]; + int other; /* set if module is for PAM_DEFAULT_SERVICE */ + int res; /* module added successfully? */ + int handler_type = PAM_HT_MODULE; /* regular handler from a module */ + int argc; + char **argv; + int argvlen; + + D(("_pam_init_handler: LINE: %s", buf)); + if (known_service != NULL) { + nexttok = buf; + /* No service field: all lines are for the known service. */ + this_service = known_service; + } else { + this_service = tok = _pam_StrTok(buf, " \n\t", &nexttok); + } + +#ifdef PAM_READ_BOTH_CONFS + if (not_other) + other = 0; + else +#endif /* PAM_READ_BOTH_CONFS */ + other = !strcasecmp(this_service, PAM_DEFAULT_SERVICE); + + /* accept "service name" or PAM_DEFAULT_SERVICE modules */ + if (!strcasecmp(this_service, pamh->service_name) || other) { + int pam_include = 0; + int substack = 0; + + /* This is a service we are looking for */ + D(("_pam_init_handlers: Found PAM config entry for: %s" + , this_service)); + + tok = _pam_StrTok(NULL, " \n\t", &nexttok); + if (tok == NULL) { + /* module type does not exist */ + D(("_pam_init_handlers: empty module type for %s", this_service)); + pam_syslog(pamh, LOG_ERR, + "(%s) empty module type", this_service); + module_type = (requested_module_type != PAM_T_ANY) ? + requested_module_type : PAM_T_AUTH; /* most sensitive */ + handler_type = PAM_HT_MUST_FAIL; /* install as normal but fail when dispatched */ + } else { + if (tok[0] == '-') { /* do not log module load errors */ + handler_type = PAM_HT_SILENT_MODULE; + ++tok; + } + if (!strcasecmp("auth", tok)) { + module_type = PAM_T_AUTH; + } else if (!strcasecmp("session", tok)) { + module_type = PAM_T_SESS; + } else if (!strcasecmp("account", tok)) { + module_type = PAM_T_ACCT; + } else if (!strcasecmp("password", tok)) { + module_type = PAM_T_PASS; + } else { + /* Illegal module type */ + D(("_pam_init_handlers: bad module type: %s", tok)); + pam_syslog(pamh, LOG_ERR, "(%s) illegal module type: %s", + this_service, tok); + module_type = (requested_module_type != PAM_T_ANY) ? + requested_module_type : PAM_T_AUTH; /* most sensitive */ + handler_type = PAM_HT_MUST_FAIL; /* install as normal but fail when dispatched */ + } + } + D(("Using %s config entry: %s", handler_type?"BAD ":"", tok)); + if (requested_module_type != PAM_T_ANY && + module_type != requested_module_type) { + D(("Skipping config entry: %s (requested=%d, found=%d)", + tok, requested_module_type, module_type)); + continue; + } + + /* reset the actions to .._UNDEF's -- this is so that + we can work out which entries are not yet set (for default). */ + { + int i; + for (i=0; i<_PAM_RETURN_VALUES; + actions[i++] = _PAM_ACTION_UNDEF); + } + tok = _pam_StrTok(NULL, " \n\t", &nexttok); + if (tok == NULL) { + /* no module name given */ + D(("_pam_init_handlers: no control flag supplied")); + pam_syslog(pamh, LOG_ERR, + "(%s) no control flag supplied", this_service); + _pam_set_default_control(actions, _PAM_ACTION_BAD); + handler_type = PAM_HT_MUST_FAIL; + } else if (!strcasecmp("required", tok)) { + D(("*PAM_F_REQUIRED*")); + actions[PAM_SUCCESS] = _PAM_ACTION_OK; + actions[PAM_NEW_AUTHTOK_REQD] = _PAM_ACTION_OK; + actions[PAM_IGNORE] = _PAM_ACTION_IGNORE; + _pam_set_default_control(actions, _PAM_ACTION_BAD); + } else if (!strcasecmp("requisite", tok)) { + D(("*PAM_F_REQUISITE*")); + actions[PAM_SUCCESS] = _PAM_ACTION_OK; + actions[PAM_NEW_AUTHTOK_REQD] = _PAM_ACTION_OK; + actions[PAM_IGNORE] = _PAM_ACTION_IGNORE; + _pam_set_default_control(actions, _PAM_ACTION_DIE); + } else if (!strcasecmp("optional", tok)) { + D(("*PAM_F_OPTIONAL*")); + actions[PAM_SUCCESS] = _PAM_ACTION_OK; + actions[PAM_NEW_AUTHTOK_REQD] = _PAM_ACTION_OK; + _pam_set_default_control(actions, _PAM_ACTION_IGNORE); + } else if (!strcasecmp("sufficient", tok)) { + D(("*PAM_F_SUFFICIENT*")); + actions[PAM_SUCCESS] = _PAM_ACTION_DONE; + actions[PAM_NEW_AUTHTOK_REQD] = _PAM_ACTION_DONE; + _pam_set_default_control(actions, _PAM_ACTION_IGNORE); + } else if (!strcasecmp("include", tok)) { + D(("*PAM_F_INCLUDE*")); + pam_include = 1; + substack = 0; + } else if (!strcasecmp("substack", tok)) { + D(("*PAM_F_SUBSTACK*")); + pam_include = 1; + substack = 1; + } else { + D(("will need to parse %s", tok)); + _pam_parse_control(actions, tok); + /* by default the default is to treat as failure */ + _pam_set_default_control(actions, _PAM_ACTION_BAD); + } + + tok = _pam_StrTok(NULL, " \n\t", &nexttok); + if (pam_include) { + if (substack) { + res = _pam_add_handler(pamh, PAM_HT_SUBSTACK, other, + stack_level, module_type, actions, tok, + 0, NULL, 0); + if (res != PAM_SUCCESS) { + pam_syslog(pamh, LOG_ERR, "error adding substack %s", tok); + D(("failed to load module - aborting")); + return PAM_ABORT; + } + } + if (_pam_load_conf_file(pamh, tok, this_service, module_type, + stack_level + substack +#ifdef PAM_READ_BOTH_CONFS + , !other +#endif /* PAM_READ_BOTH_CONFS */ + ) == PAM_SUCCESS) + continue; + _pam_set_default_control(actions, _PAM_ACTION_BAD); + mod_path = NULL; + handler_type = PAM_HT_MUST_FAIL; + nexttok = NULL; + } else if (tok != NULL) { + mod_path = tok; + D(("mod_path = %s",mod_path)); + } else { + /* no module name given */ + D(("_pam_init_handlers: no module name supplied")); + pam_syslog(pamh, LOG_ERR, + "(%s) no module name supplied", this_service); + mod_path = NULL; + handler_type = PAM_HT_MUST_FAIL; + } + + /* nexttok points to remaining arguments... */ + + if (nexttok != NULL) { + D(("list: %s",nexttok)); + argvlen = _pam_mkargv(nexttok, &argv, &argc); + D(("argvlen = %d",argvlen)); + } else { /* there are no arguments so fix by hand */ + D(("_pam_init_handlers: empty argument list")); + argvlen = argc = 0; + argv = NULL; + } + +#ifdef PAM_DEBUG + { + int y; + + D(("CONF%s: %s%s %d %s %d" + , handler_type==PAM_HT_MUST_FAIL?"<*will fail*>":"" + , this_service, other ? "(backup)":"" + , module_type + , mod_path, argc)); + for (y = 0; y < argc; y++) { + D(("CONF: %s", argv[y])); + } + for (y = 0; y<_PAM_RETURN_VALUES; ++y) { + D(("RETURN %s(%d) -> %d %s", + _pam_token_returns[y], y, actions[y], + actions[y]>0 ? "jump": + _pam_token_actions[-actions[y]])); + } + } +#endif + + res = _pam_add_handler(pamh, handler_type, other, stack_level + , module_type, actions, mod_path + , argc, argv, argvlen); + if (res != PAM_SUCCESS) { + pam_syslog(pamh, LOG_ERR, "error loading %s", mod_path); + D(("failed to load module - aborting")); + return PAM_ABORT; + } + } + } + + return ( (x < 0) ? PAM_ABORT:PAM_SUCCESS ); +} + +static int +_pam_open_config_file(pam_handle_t *pamh + , const char *service + , char **path + , FILE **file) +{ + const char *pamd_dirs[] = { PAM_CONFIG_DF, PAM_CONFIG_DIST_DF +#ifdef VENDORDIR + , PAM_CONFIG_DIST2_DF +#endif + }; + char *p = NULL; + FILE *f; + size_t i; + + /* Absolute path */ + if (service[0] == '/') { + p = _pam_strdup(service); + if (p == NULL) { + pam_syslog(pamh, LOG_CRIT, "strdup failed"); + return PAM_BUF_ERR; + } + } else if (pamh->confdir != NULL) { + if (asprintf (&p, "%s/%s", pamh->confdir, service) < 0) { + pam_syslog(pamh, LOG_CRIT, "asprintf failed"); + return PAM_BUF_ERR; + } + } + + if (p != NULL) { + D(("opening %s", p)); + f = fopen(p, "r"); + if (f != NULL) { + *path = p; + *file = f; + return PAM_SUCCESS; + } + _pam_drop(p); + return PAM_ABORT; + } + + for (i = 0; i < PAM_ARRAY_SIZE(pamd_dirs); i++) { + if (asprintf (&p, pamd_dirs[i], service) < 0) { + pam_syslog(pamh, LOG_CRIT, "asprintf failed"); + return PAM_BUF_ERR; + } + + D(("opening %s", p)); + f = fopen(p, "r"); + if (f != NULL) { + *path = p; + *file = f; + return PAM_SUCCESS; + } + _pam_drop(p); + } + + return PAM_ABORT; +} + +static int _pam_load_conf_file(pam_handle_t *pamh, const char *config_name + , const char *service /* specific file */ + , int module_type /* specific type */ + , int stack_level /* level of substack */ +#ifdef PAM_READ_BOTH_CONFS + , int not_other +#endif /* PAM_READ_BOTH_CONFS */ + ) +{ + FILE *f; + char *path = NULL; + int retval = PAM_ABORT; + + D(("_pam_load_conf_file called")); + + if (stack_level >= PAM_SUBSTACK_MAX_LEVEL) { + D(("maximum level of substacks reached")); + pam_syslog(pamh, LOG_ERR, "maximum level of substacks reached"); + return PAM_ABORT; + } + + if (config_name == NULL) { + D(("no config file supplied")); + pam_syslog(pamh, LOG_ERR, "(%s) no config name supplied", service); + return PAM_ABORT; + } + + if (_pam_open_config_file(pamh, config_name, &path, &f) == PAM_SUCCESS) { + retval = _pam_parse_conf_file(pamh, f, service, module_type, stack_level +#ifdef PAM_READ_BOTH_CONFS + , not_other +#endif /* PAM_READ_BOTH_CONFS */ + ); + if (retval != PAM_SUCCESS) + pam_syslog(pamh, LOG_ERR, + "_pam_load_conf_file: error reading %s: %s", + path, pam_strerror(pamh, retval)); + _pam_drop(path); + fclose(f); + } else { + D(("unable to open %s", config_name)); + pam_syslog(pamh, LOG_ERR, + "_pam_load_conf_file: unable to open config for %s", + config_name); + } + + return retval; +} + +/* Parse config file, allocate handler structures, dlopen() */ +int _pam_init_handlers(pam_handle_t *pamh) +{ + FILE *f; + int retval; + + D(("_pam_init_handlers called")); + IF_NO_PAMH("_pam_init_handlers",pamh,PAM_SYSTEM_ERR); + + /* Return immediately if everything is already loaded */ + if (pamh->handlers.handlers_loaded) { + return PAM_SUCCESS; + } + + D(("_pam_init_handlers: initializing")); + + /* First clean the service structure */ + + _pam_free_handlers(pamh); + if (! pamh->handlers.module) { + if ((pamh->handlers.module = + malloc(MODULE_CHUNK * sizeof(struct loaded_module))) == NULL) { + pam_syslog(pamh, LOG_CRIT, + "_pam_init_handlers: no memory loading module"); + return PAM_BUF_ERR; + } + pamh->handlers.modules_allocated = MODULE_CHUNK; + pamh->handlers.modules_used = 0; + } + + if (pamh->service_name == NULL) { + return PAM_BAD_ITEM; /* XXX - better error? */ + } + +#ifdef PAM_LOCKING + /* Is the PAM subsystem locked? */ + { + int fd_tmp; + + if ((fd_tmp = open( PAM_LOCK_FILE, O_RDONLY )) != -1) { + pam_syslog(pamh, LOG_ERR, + "_pam_init_handlers: PAM lockfile (" + PAM_LOCK_FILE ") exists - aborting"); + (void) close(fd_tmp); + /* + * to avoid swamping the system with requests + */ + _pam_start_timer(pamh); + pam_fail_delay(pamh, 5000000); + _pam_await_timer(pamh, PAM_ABORT); + + return PAM_ABORT; + } + } +#endif /* PAM_LOCKING */ + + /* + * Now parse the config file(s) and add handlers + */ + { + struct stat test_d; + + /* Is there a PAM_CONFIG_D directory? */ + if (pamh->confdir != NULL || + (stat(PAM_CONFIG_D, &test_d) == 0 && S_ISDIR(test_d.st_mode)) || + (stat(PAM_CONFIG_DIST_D, &test_d) == 0 && S_ISDIR(test_d.st_mode)) +#ifdef PAM_CONFIG_DIST2_D + || (stat(PAM_CONFIG_DIST2_D, &test_d) == 0 + && S_ISDIR(test_d.st_mode)) +#endif + ) { + char *path = NULL; + int read_something=0; + + if (_pam_open_config_file(pamh, pamh->service_name, &path, &f) == PAM_SUCCESS) { + retval = _pam_parse_conf_file(pamh, f, pamh->service_name, + PAM_T_ANY, 0 +#ifdef PAM_READ_BOTH_CONFS + , 0 +#endif /* PAM_READ_BOTH_CONFS */ + ); + if (retval != PAM_SUCCESS) { + pam_syslog(pamh, LOG_ERR, + "_pam_init_handlers: error reading %s", + path); + pam_syslog(pamh, LOG_ERR, "_pam_init_handlers: [%s]", + pam_strerror(pamh, retval)); + } else { + read_something = 1; + } + _pam_drop(path); + fclose(f); + } else { + D(("unable to open configuration for %s", pamh->service_name)); +#ifdef PAM_READ_BOTH_CONFS + D(("checking %s", PAM_CONFIG)); + + if (pamh->confdir == NULL + && (f = fopen(PAM_CONFIG,"r")) != NULL) { + retval = _pam_parse_conf_file(pamh, f, NULL, PAM_T_ANY, 0, 1); + fclose(f); + } else +#endif /* PAM_READ_BOTH_CONFS */ + retval = PAM_SUCCESS; + /* + * XXX - should we log an error? Some people want to always + * use "other" + */ + } + + if (retval == PAM_SUCCESS) { + /* now parse the PAM_DEFAULT_SERVICE */ + + if (_pam_open_config_file(pamh, PAM_DEFAULT_SERVICE, &path, &f) == PAM_SUCCESS) { + /* would test magic here? */ + retval = _pam_parse_conf_file(pamh, f, PAM_DEFAULT_SERVICE, + PAM_T_ANY, 0 +#ifdef PAM_READ_BOTH_CONFS + , 0 +#endif /* PAM_READ_BOTH_CONFS */ + ); + if (retval != PAM_SUCCESS) { + pam_syslog(pamh, LOG_ERR, + "_pam_init_handlers: error reading %s", + path); + pam_syslog(pamh, LOG_ERR, + "_pam_init_handlers: [%s]", + pam_strerror(pamh, retval)); + } else { + read_something = 1; + } + _pam_drop(path); + fclose(f); + } else { + D(("unable to open %s", PAM_DEFAULT_SERVICE)); + pam_syslog(pamh, LOG_ERR, + "_pam_init_handlers: no default config %s", + PAM_DEFAULT_SERVICE); + } + if (!read_something) { /* nothing read successfully */ + retval = PAM_ABORT; + } + } + } else { + if ((f = fopen(PAM_CONFIG, "r")) == NULL) { + pam_syslog(pamh, LOG_ERR, "_pam_init_handlers: could not open " + PAM_CONFIG ); + return PAM_ABORT; + } + + retval = _pam_parse_conf_file(pamh, f, NULL, PAM_T_ANY, 0 +#ifdef PAM_READ_BOTH_CONFS + , 0 +#endif /* PAM_READ_BOTH_CONFS */ + ); + + D(("closing configuration file")); + fclose(f); + } + } + + if (retval != PAM_SUCCESS) { + /* Read error */ + pam_syslog(pamh, LOG_ERR, "error reading PAM configuration file"); + return PAM_ABORT; + } + + pamh->handlers.handlers_loaded = 1; + + D(("_pam_init_handlers exiting")); + return PAM_SUCCESS; +} + +/* + * This is where we read a line of the PAM config file. The line may be + * preceded by lines of comments and also extended with "\\\n" + */ + +static int _pam_assemble_line(FILE *f, char *buffer, int buf_len) +{ + char *p = buffer; + char *endp = buffer + buf_len; + char *s, *os; + int used = 0; + + /* loop broken with a 'break' when a non-'\\n' ended line is read */ + + D(("called.")); + for (;;) { + if (p >= endp) { + /* Overflow */ + D(("_pam_assemble_line: overflow")); + return -1; + } + if (fgets(p, endp - p, f) == NULL) { + if (used) { + /* Incomplete read */ + return -1; + } else { + /* EOF */ + return 0; + } + } + + /* skip leading spaces --- line may be blank */ + + s = p + strspn(p, " \n\t"); + if (*s && (*s != '#')) { + os = s; + + /* + * we are only interested in characters before the first '#' + * character + */ + + while (*s && *s != '#') + ++s; + if (*s == '#') { + *s = '\0'; + used += strlen(os); + break; /* the line has been read */ + } + + s = os; + + /* + * Check for backslash by scanning back from the end of + * the entered line, the '\n' has been included since + * normally a line is terminated with this + * character. fgets() should only return one though! + */ + + s += strlen(s); + while (s > os && ((*--s == ' ') || (*s == '\t') + || (*s == '\n'))); + + /* check if it ends with a backslash */ + if (*s == '\\') { + *s++ = ' '; /* replace backslash with ' ' */ + *s = '\0'; /* truncate the line here */ + used += strlen(os); + p = s; /* there is more ... */ + } else { + /* End of the line! */ + used += strlen(os); + break; /* this is the complete line */ + } + + } else { + /* Nothing in this line */ + /* Don't move p */ + } + } + + return used; +} + +static char * +extract_modulename(const char *mod_path) +{ + const char *p = strrchr (mod_path, '/'); + char *dot, *retval; + + if (p == NULL) + p = mod_path; + else + p++; + + if ((retval = _pam_strdup (p)) == NULL) + return NULL; + + dot = strrchr (retval, '.'); + if (dot) + *dot = '\0'; + + if (*retval == '\0' || strcmp(retval, "?") == 0) { + /* do not allow empty module name or "?" to avoid confusing audit trail */ + _pam_drop(retval); + return NULL; + } + + return retval; +} + +static struct loaded_module * +_pam_load_module(pam_handle_t *pamh, const char *mod_path, int handler_type) +{ + int x = 0; + int success; + struct loaded_module *mod; + + D(("_pam_load_module: loading module `%s'", mod_path)); + + mod = pamh->handlers.module; + + /* First, ensure the module is loaded */ + while (x < pamh->handlers.modules_used) { + if (!strcmp(mod[x].name, mod_path)) { /* case sensitive ! */ + break; + } + x++; + } + if (x == pamh->handlers.modules_used) { + /* Not found */ + if (pamh->handlers.modules_allocated == pamh->handlers.modules_used) { + /* will need more memory */ + void *tmp = realloc(pamh->handlers.module, + (pamh->handlers.modules_allocated+MODULE_CHUNK) + *sizeof(struct loaded_module)); + if (tmp == NULL) { + D(("cannot enlarge module pointer memory")); + pam_syslog(pamh, LOG_CRIT, + "realloc returned NULL in _pam_load_module"); + return NULL; + } + pamh->handlers.module = tmp; + pamh->handlers.modules_allocated += MODULE_CHUNK; + } + mod = &(pamh->handlers.module[x]); + /* Be pessimistic... */ + success = PAM_ABORT; + + D(("_pam_load_module: _pam_dlopen(%s)", mod_path)); + mod->dl_handle = _pam_dlopen(mod_path); + D(("_pam_load_module: _pam_dlopen'ed")); + D(("_pam_load_module: dlopen'ed")); + if (mod->dl_handle == NULL) { + const char *isa = strstr(mod_path, "$ISA"); + size_t isa_len = strlen("$ISA"); + + if (isa != NULL) { + size_t pam_isa_len = strlen(_PAM_ISA); + char *mod_full_isa_path = + malloc(strlen(mod_path) - isa_len + pam_isa_len + 1); + + if (mod_full_isa_path == NULL) { + D(("_pam_load_module: couldn't get memory for mod_path")); + pam_syslog(pamh, LOG_CRIT, "no memory for module path"); + success = PAM_ABORT; + } else { + char *p = mod_full_isa_path; + + memcpy(p, mod_path, isa - mod_path); + p += isa - mod_path; + memcpy(p, _PAM_ISA, pam_isa_len); + p += pam_isa_len; + strcpy(p, isa + isa_len); + + mod->dl_handle = _pam_dlopen(mod_full_isa_path); + _pam_drop(mod_full_isa_path); + } + } + } + if (mod->dl_handle == NULL) { + D(("_pam_load_module: _pam_dlopen(%s) failed", mod_path)); + if (handler_type != PAM_HT_SILENT_MODULE) + pam_syslog(pamh, LOG_ERR, "unable to dlopen(%s): %s", mod_path, + _pam_dlerror()); + /* Don't abort yet; static code may be able to find function. + * But defaults to abort if nothing found below... */ + } else { + D(("module added successfully")); + success = PAM_SUCCESS; + mod->type = PAM_MT_DYNAMIC_MOD; + pamh->handlers.modules_used++; + } + + if (success != PAM_SUCCESS) { /* add a malformed module */ + mod->dl_handle = NULL; + mod->type = PAM_MT_FAULTY_MOD; + pamh->handlers.modules_used++; + if (handler_type != PAM_HT_SILENT_MODULE) + pam_syslog(pamh, LOG_ERR, "adding faulty module: %s", mod_path); + success = PAM_SUCCESS; /* We have successfully added a module */ + } + + /* indicate its name - later we will search for it by this */ + if ((mod->name = _pam_strdup(mod_path)) == NULL) { + D(("_pam_load_module: couldn't get memory for mod_path")); + pam_syslog(pamh, LOG_CRIT, "no memory for module path"); + success = PAM_ABORT; + } + + } else { /* x != pamh->handlers.modules_used */ + mod += x; /* the located module */ + success = PAM_SUCCESS; + } + return success == PAM_SUCCESS ? mod : NULL; +} + +int _pam_add_handler(pam_handle_t *pamh + , int handler_type, int other, int stack_level, int type + , int *actions, const char *mod_path + , int argc, char **argv, int argvlen) +{ + struct loaded_module *mod = NULL; + struct handler **handler_p; + struct handler **handler_p2; + struct handlers *the_handlers; + const char *sym, *sym2; + char *mod_full_path; + servicefn func, func2; + int mod_type = PAM_MT_FAULTY_MOD; + + D(("called.")); + IF_NO_PAMH("_pam_add_handler",pamh,PAM_SYSTEM_ERR); + + D(("_pam_add_handler: adding type %d, handler_type %d, module `%s'", + type, handler_type, mod_path)); + + if ((handler_type == PAM_HT_MODULE || handler_type == PAM_HT_SILENT_MODULE) && + mod_path != NULL) { + if (mod_path[0] == '/') { + mod = _pam_load_module(pamh, mod_path, handler_type); + } else if (asprintf(&mod_full_path, "%s%s", + DEFAULT_MODULE_PATH, mod_path) >= 0) { + mod = _pam_load_module(pamh, mod_full_path, handler_type); + _pam_drop(mod_full_path); + } else { + pam_syslog(pamh, LOG_CRIT, "cannot malloc full mod path"); + return PAM_ABORT; + } + + if (mod == NULL) { + /* if we get here with NULL it means allocation error */ + return PAM_ABORT; + } + + mod_type = mod->type; + } + + if (mod_path == NULL) + mod_path = UNKNOWN_MODULE; + + /* + * At this point 'mod' points to the stored/loaded module. + */ + + /* Now define the handler(s) based on mod->dlhandle and type */ + + /* decide which list of handlers to use */ + the_handlers = (other) ? &pamh->handlers.other : &pamh->handlers.conf; + + handler_p = handler_p2 = NULL; + func = func2 = NULL; + sym2 = NULL; + + /* point handler_p's at the root addresses of the function stacks */ + switch (type) { + case PAM_T_AUTH: + handler_p = &the_handlers->authenticate; + sym = "pam_sm_authenticate"; + handler_p2 = &the_handlers->setcred; + sym2 = "pam_sm_setcred"; + break; + case PAM_T_SESS: + handler_p = &the_handlers->open_session; + sym = "pam_sm_open_session"; + handler_p2 = &the_handlers->close_session; + sym2 = "pam_sm_close_session"; + break; + case PAM_T_ACCT: + handler_p = &the_handlers->acct_mgmt; + sym = "pam_sm_acct_mgmt"; + break; + case PAM_T_PASS: + handler_p = &the_handlers->chauthtok; + sym = "pam_sm_chauthtok"; + break; + default: + /* Illegal module type */ + D(("_pam_add_handler: illegal module type %d", type)); + return PAM_ABORT; + } + + /* are the modules reliable? */ + if (mod_type != PAM_MT_DYNAMIC_MOD && + mod_type != PAM_MT_FAULTY_MOD) { + D(("_pam_add_handlers: illegal module library type; %d", mod_type)); + pam_syslog(pamh, LOG_ERR, + "internal error: module library type not known: %s;%d", + sym, mod_type); + return PAM_ABORT; + } + + /* now identify this module's functions - for non-faulty modules */ + + if ((mod_type == PAM_MT_DYNAMIC_MOD) && + !(func = _pam_dlsym(mod->dl_handle, sym)) ) { + pam_syslog(pamh, LOG_ERR, "unable to resolve symbol: %s", sym); + } + if (sym2) { + if ((mod_type == PAM_MT_DYNAMIC_MOD) && + !(func2 = _pam_dlsym(mod->dl_handle, sym2)) ) { + pam_syslog(pamh, LOG_ERR, "unable to resolve symbol: %s", sym2); + } + } + + /* here func (and perhaps func2) point to the appropriate functions */ + + /* add new handler to end of existing list */ + while (*handler_p != NULL) { + handler_p = &((*handler_p)->next); + } + + if ((*handler_p = malloc(sizeof(struct handler))) == NULL) { + pam_syslog(pamh, LOG_CRIT, "cannot malloc struct handler #1"); + return (PAM_ABORT); + } + + (*handler_p)->handler_type = handler_type; + (*handler_p)->stack_level = stack_level; + (*handler_p)->func = func; + memcpy((*handler_p)->actions,actions,sizeof((*handler_p)->actions)); + (*handler_p)->cached_retval = _PAM_INVALID_RETVAL; + (*handler_p)->cached_retval_p = &((*handler_p)->cached_retval); + (*handler_p)->argc = argc; + (*handler_p)->argv = argv; /* not a copy */ + if (((*handler_p)->mod_name = extract_modulename(mod_path)) == NULL) + return PAM_ABORT; + (*handler_p)->grantor = 0; + (*handler_p)->next = NULL; + + /* some of the modules have a second calling function */ + if (handler_p2) { + /* add new handler to end of existing list */ + while (*handler_p2) { + handler_p2 = &((*handler_p2)->next); + } + + if ((*handler_p2 = malloc(sizeof(struct handler))) == NULL) { + pam_syslog(pamh, LOG_CRIT, "cannot malloc struct handler #2"); + return (PAM_ABORT); + } + + (*handler_p2)->handler_type = handler_type; + (*handler_p2)->stack_level = stack_level; + (*handler_p2)->func = func2; + memcpy((*handler_p2)->actions,actions,sizeof((*handler_p2)->actions)); + (*handler_p2)->cached_retval = _PAM_INVALID_RETVAL; /* ignored */ + /* Note, this next entry points to the handler_p value! */ + (*handler_p2)->cached_retval_p = &((*handler_p)->cached_retval); + (*handler_p2)->argc = argc; + if (argv) { + if (((*handler_p2)->argv = malloc(argvlen)) == NULL) { + pam_syslog(pamh, LOG_CRIT, "cannot malloc argv for handler #2"); + return (PAM_ABORT); + } + memcpy((*handler_p2)->argv, argv, argvlen); + } else { + (*handler_p2)->argv = NULL; /* no arguments */ + } + if (((*handler_p2)->mod_name = extract_modulename(mod_path)) == NULL) + return PAM_ABORT; + (*handler_p2)->grantor = 0; + (*handler_p2)->next = NULL; + } + + D(("_pam_add_handler: returning successfully")); + + return PAM_SUCCESS; +} + +/* Free various allocated structures and dlclose() the libs */ +int _pam_free_handlers(pam_handle_t *pamh) +{ + struct loaded_module *mod; + + D(("called.")); + IF_NO_PAMH("_pam_free_handlers",pamh,PAM_SYSTEM_ERR); + + mod = pamh->handlers.module; + + /* Close all loaded modules */ + + while (pamh->handlers.modules_used) { + D(("_pam_free_handlers: dlclose(%s)", mod->name)); + free(mod->name); + if (mod->type == PAM_MT_DYNAMIC_MOD) { + _pam_dlclose(mod->dl_handle); + } + mod++; + pamh->handlers.modules_used--; + } + + /* Free all the handlers */ + + _pam_free_handlers_aux(&(pamh->handlers.conf.authenticate)); + _pam_free_handlers_aux(&(pamh->handlers.conf.setcred)); + _pam_free_handlers_aux(&(pamh->handlers.conf.acct_mgmt)); + _pam_free_handlers_aux(&(pamh->handlers.conf.open_session)); + _pam_free_handlers_aux(&(pamh->handlers.conf.close_session)); + _pam_free_handlers_aux(&(pamh->handlers.conf.chauthtok)); + + _pam_free_handlers_aux(&(pamh->handlers.other.authenticate)); + _pam_free_handlers_aux(&(pamh->handlers.other.setcred)); + _pam_free_handlers_aux(&(pamh->handlers.other.acct_mgmt)); + _pam_free_handlers_aux(&(pamh->handlers.other.open_session)); + _pam_free_handlers_aux(&(pamh->handlers.other.close_session)); + _pam_free_handlers_aux(&(pamh->handlers.other.chauthtok)); + + /* no more loaded modules */ + + _pam_drop(pamh->handlers.module); + + /* Indicate that handlers are not initialized for this pamh */ + + pamh->handlers.handlers_loaded = 0; + + return PAM_SUCCESS; +} + +void _pam_start_handlers(pam_handle_t *pamh) +{ + D(("called.")); + /* NB. There is no check for a NULL pamh here, since no return + * value to communicate the fact! */ + + /* Indicate that handlers are not initialized for this pamh */ + pamh->handlers.handlers_loaded = 0; + + pamh->handlers.modules_allocated = 0; + pamh->handlers.modules_used = 0; + pamh->handlers.module = NULL; + + /* initialize the .conf and .other entries */ + + pamh->handlers.conf.authenticate = NULL; + pamh->handlers.conf.setcred = NULL; + pamh->handlers.conf.acct_mgmt = NULL; + pamh->handlers.conf.open_session = NULL; + pamh->handlers.conf.close_session = NULL; + pamh->handlers.conf.chauthtok = NULL; + + pamh->handlers.other.authenticate = NULL; + pamh->handlers.other.setcred = NULL; + pamh->handlers.other.acct_mgmt = NULL; + pamh->handlers.other.open_session = NULL; + pamh->handlers.other.close_session = NULL; + pamh->handlers.other.chauthtok = NULL; +} + +void _pam_free_handlers_aux(struct handler **hp) +{ + struct handler *h = *hp; + struct handler *last; + + D(("called.")); + while (h) { + last = h; + _pam_drop(h->argv); /* This is all allocated in a single chunk */ + _pam_drop(h->mod_name); + h = h->next; + memset(last, 0, sizeof(*last)); + free(last); + } + + *hp = NULL; +} |