/* * SPDX-License-Identifier: ISC * * Copyright (c) 2009-2021 Todd C. Miller * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ /* * This is an open source non-commercial project. Dear PVS-Studio, please check it. * PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com */ #include #include #include #include #ifdef HAVE_STDBOOL_H # include #else # include "compat/stdbool.h" #endif #include #ifdef HAVE_STRINGS_H # include #endif /* HAVE_STRINGS_H */ #include #include #include #include #include #define SUDO_ERROR_WRAP 0 #include "sudo_compat.h" #include "sudo_conf.h" #include "sudo_debug.h" #include "sudo_fatal.h" #include "sudo_gettext.h" #include "sudo_plugin.h" #include "sudo_util.h" #include "pathnames.h" #ifndef _PATH_SUDO_INTERCEPT # define _PATH_SUDO_INTERCEPT NULL #endif #ifndef _PATH_SUDO_NOEXEC # define _PATH_SUDO_NOEXEC NULL #endif struct sudo_conf_table { const char *name; unsigned int namelen; int (*parser)(const char *entry, const char *conf_file, unsigned int lineno); }; struct sudo_conf_path_table { const char *pname; unsigned int pnamelen; bool dynamic; const char *pval; }; struct sudo_conf_settings { bool updated; bool disable_coredump; bool probe_interfaces; int group_source; int max_groups; }; static int parse_debug(const char *entry, const char *conf_file, unsigned int lineno); static int parse_path(const char *entry, const char *conf_file, unsigned int lineno); static int parse_plugin(const char *entry, const char *conf_file, unsigned int lineno); static int parse_variable(const char *entry, const char *conf_file, unsigned int lineno); static struct sudo_conf_table sudo_conf_table[] = { { "Debug", sizeof("Debug") - 1, parse_debug }, { "Path", sizeof("Path") - 1, parse_path }, { "Plugin", sizeof("Plugin") - 1, parse_plugin }, { "Set", sizeof("Set") - 1, parse_variable }, { NULL } }; static int set_var_disable_coredump(const char *entry, const char *conf_file, unsigned int); static int set_var_group_source(const char *entry, const char *conf_file, unsigned int); static int set_var_max_groups(const char *entry, const char *conf_file, unsigned int); static int set_var_probe_interfaces(const char *entry, const char *conf_file, unsigned int); static struct sudo_conf_table sudo_conf_var_table[] = { { "disable_coredump", sizeof("disable_coredump") - 1, set_var_disable_coredump }, { "group_source", sizeof("group_source") - 1, set_var_group_source }, { "max_groups", sizeof("max_groups") - 1, set_var_max_groups }, { "probe_interfaces", sizeof("probe_interfaces") - 1, set_var_probe_interfaces }, { NULL } }; /* Indexes into path_table[] below (order is important). */ #define SUDO_CONF_PATH_ASKPASS 0 #define SUDO_CONF_PATH_SESH 1 #define SUDO_CONF_PATH_INTERCEPT 2 #define SUDO_CONF_PATH_NOEXEC 3 #define SUDO_CONF_PATH_PLUGIN_DIR 4 #define SUDO_CONF_PATH_DEVSEARCH 5 #define SUDO_CONF_PATH_INITIALIZER { \ { "askpass", sizeof("askpass") - 1, false, _PATH_SUDO_ASKPASS }, \ { "sesh", sizeof("sesh") - 1, false, _PATH_SUDO_SESH }, \ { "intercept", sizeof("intercept") - 1, false, _PATH_SUDO_INTERCEPT }, \ { "noexec", sizeof("noexec") - 1, false, _PATH_SUDO_NOEXEC }, \ { "plugin_dir", sizeof("plugin_dir") - 1, false, _PATH_SUDO_PLUGIN_DIR }, \ { "devsearch", sizeof("devsearch") - 1, false, _PATH_SUDO_DEVSEARCH }, \ { NULL } \ } /* * getgroups(2) on macOS is flakey with respect to non-local groups. * Even with _DARWIN_UNLIMITED_GETGROUPS set we may not get all groups./ * See bug #946 for details. */ #ifdef __APPLE__ # define GROUP_SOURCE_DEFAULT GROUP_SOURCE_DYNAMIC #else # define GROUP_SOURCE_DEFAULT GROUP_SOURCE_ADAPTIVE #endif #define SUDO_CONF_SETTINGS_INITIALIZER { \ false, /* updated */ \ true, /* disable_coredump */ \ true, /* probe_interfaces */ \ GROUP_SOURCE_DEFAULT, /* group_source */ \ -1 /* max_groups */ \ } static struct sudo_conf_data { struct sudo_conf_settings settings; struct sudo_conf_debug_list debugging; struct plugin_info_list plugins; struct sudo_conf_path_table path_table[7]; } sudo_conf_data = { SUDO_CONF_SETTINGS_INITIALIZER, TAILQ_HEAD_INITIALIZER(sudo_conf_data.debugging), TAILQ_HEAD_INITIALIZER(sudo_conf_data.plugins), SUDO_CONF_PATH_INITIALIZER }; /* * "Set variable_name value" */ static int parse_variable(const char *entry, const char *conf_file, unsigned int lineno) { struct sudo_conf_table *var; int ret; debug_decl(parse_variable, SUDO_DEBUG_UTIL); for (var = sudo_conf_var_table; var->name != NULL; var++) { if (strncmp(entry, var->name, var->namelen) == 0 && isblank((unsigned char)entry[var->namelen])) { entry += var->namelen + 1; while (isblank((unsigned char)*entry)) entry++; ret = var->parser(entry, conf_file, lineno); sudo_debug_printf(ret ? SUDO_DEBUG_INFO : SUDO_DEBUG_ERROR, "%s: %s:%u: Set %s %s", __func__, conf_file, lineno, var->name, entry); debug_return_int(ret); } } sudo_debug_printf(SUDO_DEBUG_WARN, "%s: %s:%u: unknown setting %s", __func__, conf_file, lineno, entry); debug_return_int(false); } /* * "Path name /path/to/file" * If path is missing it will be set to the NULL pointer. */ static int parse_path(const char *entry, const char *conf_file, unsigned int lineno) { const char *entry_end = entry + strlen(entry); const char *ep, *name, *path; struct sudo_conf_path_table *cur; size_t namelen; debug_decl(parse_path, SUDO_DEBUG_UTIL); /* Parse name. */ name = sudo_strsplit(entry, entry_end, " \t", &ep); if (name == NULL) goto bad; namelen = (size_t)(ep - name); /* Parse path (if present). */ path = sudo_strsplit(NULL, entry_end, " \t", &ep); /* Match supported paths, ignoring unknown paths. */ for (cur = sudo_conf_data.path_table; cur->pname != NULL; cur++) { if (namelen == cur->pnamelen && strncasecmp(name, cur->pname, cur->pnamelen) == 0) { char *pval = NULL; if (path != NULL) { if ((pval = strdup(path)) == NULL) { sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory")); debug_return_int(-1); } } if (cur->dynamic) free((char *)cur->pval); cur->pval = pval; cur->dynamic = true; sudo_debug_printf(SUDO_DEBUG_INFO, "%s: %s:%u: Path %s %s", __func__, conf_file, lineno, cur->pname, pval ? pval : "(none)"); debug_return_int(true); } } sudo_debug_printf(SUDO_DEBUG_WARN, "%s: %s:%u: unknown path %s", __func__, conf_file, lineno, entry); debug_return_int(false); bad: sudo_warnx(U_("invalid Path value \"%s\" in %s, line %u"), entry, conf_file, lineno); debug_return_int(false); } /* * "Debug program /path/to/log flags,..." */ static int parse_debug(const char *entry, const char *conf_file, unsigned int lineno) { struct sudo_conf_debug *debug_spec; struct sudo_debug_file *debug_file = NULL; const char *ep, *path, *progname, *flags; const char *entry_end = entry + strlen(entry); size_t pathlen, prognamelen; debug_decl(parse_debug, SUDO_DEBUG_UTIL); /* Parse progname. */ progname = sudo_strsplit(entry, entry_end, " \t", &ep); if (progname == NULL) debug_return_int(false); /* not enough fields */ prognamelen = (size_t)(ep - progname); /* Parse path. */ path = sudo_strsplit(NULL, entry_end, " \t", &ep); if (path == NULL) debug_return_int(false); /* not enough fields */ pathlen = (size_t)(ep - path); /* Remainder is flags (freeform). */ flags = sudo_strsplit(NULL, entry_end, " \t", &ep); if (flags == NULL) debug_return_int(false); /* not enough fields */ /* If progname already exists, use it, else alloc a new one. */ TAILQ_FOREACH(debug_spec, &sudo_conf_data.debugging, entries) { if (strncmp(debug_spec->progname, progname, prognamelen) == 0 && debug_spec->progname[prognamelen] == '\0') break; } if (debug_spec == NULL) { debug_spec = malloc(sizeof(*debug_spec)); if (debug_spec == NULL) goto oom; debug_spec->progname = strndup(progname, prognamelen); if (debug_spec->progname == NULL) { free(debug_spec); debug_spec = NULL; goto oom; } TAILQ_INIT(&debug_spec->debug_files); TAILQ_INSERT_TAIL(&sudo_conf_data.debugging, debug_spec, entries); } debug_file = calloc(1, sizeof(*debug_file)); if (debug_file == NULL) goto oom; debug_file->debug_file = strndup(path, pathlen); if (debug_file->debug_file == NULL) goto oom; debug_file->debug_flags = strdup(flags); if (debug_file->debug_flags == NULL) goto oom; TAILQ_INSERT_TAIL(&debug_spec->debug_files, debug_file, entries); debug_return_int(true); oom: sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory")); if (debug_file != NULL) { free(debug_file->debug_file); free(debug_file->debug_flags); free(debug_file); } debug_return_int(-1); } /* * "Plugin symbol /path/to/log args..." */ static int parse_plugin(const char *entry, const char *conf_file, unsigned int lineno) { struct plugin_info *info = NULL; const char *ep, *path, *symbol; const char *entry_end = entry + strlen(entry); char **options = NULL; size_t pathlen, symlen; unsigned int nopts = 0; debug_decl(parse_plugin, SUDO_DEBUG_UTIL); /* Parse symbol. */ symbol = sudo_strsplit(entry, entry_end, " \t", &ep); if (symbol == NULL) debug_return_int(false); /* not enough fields */ symlen = (size_t)(ep - symbol); /* Parse path. */ path = sudo_strsplit(NULL, entry_end, " \t", &ep); if (path == NULL) debug_return_int(false); /* not enough fields */ pathlen = (size_t)(ep - path); /* Split options into an array if present. */ while (isblank((unsigned char)*ep)) ep++; if (*ep != '\0') { /* Count number of options and allocate array. */ const char *cp, *opt = ep; /* Count and allocate options array. */ for (nopts = 0, cp = sudo_strsplit(opt, entry_end, " \t", &ep); cp != NULL; cp = sudo_strsplit(NULL, entry_end, " \t", &ep)) { nopts++; } options = reallocarray(NULL, nopts + 1, sizeof(*options)); if (options == NULL) goto oom; /* Fill in options array. */ for (nopts = 0, cp = sudo_strsplit(opt, entry_end, " \t", &ep); cp != NULL; cp = sudo_strsplit(NULL, entry_end, " \t", &ep)) { options[nopts] = strndup(cp, (size_t)(ep - cp)); if (options[nopts] == NULL) goto oom; nopts++; } options[nopts] = NULL; } info = calloc(sizeof(*info), 1); if (info == NULL) goto oom; info->symbol_name = strndup(symbol, symlen); if (info->symbol_name == NULL) goto oom; info->path = strndup(path, pathlen); if (info->path == NULL) goto oom; info->options = options; info->lineno = lineno; TAILQ_INSERT_TAIL(&sudo_conf_data.plugins, info, entries); debug_return_int(true); oom: sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory")); if (options != NULL) { while (nopts--) free(options[nopts]); free(options); } if (info != NULL) { free(info->symbol_name); free(info->path); free(info); } debug_return_int(-1); } static int set_var_disable_coredump(const char *strval, const char *conf_file, unsigned int lineno) { int val = sudo_strtobool(strval); debug_decl(set_var_disable_coredump, SUDO_DEBUG_UTIL); if (val == -1) { sudo_warnx(U_("invalid value for %s \"%s\" in %s, line %u"), "disable_coredump", strval, conf_file, lineno); debug_return_int(false); } sudo_conf_data.settings.disable_coredump = val; debug_return_int(true); } static int set_var_group_source(const char *strval, const char *conf_file, unsigned int lineno) { debug_decl(set_var_group_source, SUDO_DEBUG_UTIL); if (strcasecmp(strval, "adaptive") == 0) { sudo_conf_data.settings.group_source = GROUP_SOURCE_ADAPTIVE; } else if (strcasecmp(strval, "static") == 0) { sudo_conf_data.settings.group_source = GROUP_SOURCE_STATIC; } else if (strcasecmp(strval, "dynamic") == 0) { sudo_conf_data.settings.group_source = GROUP_SOURCE_DYNAMIC; } else { sudo_warnx(U_("unsupported group source \"%s\" in %s, line %u"), strval, conf_file, lineno); debug_return_int(false); } debug_return_int(true); } static int set_var_max_groups(const char *strval, const char *conf_file, unsigned int lineno) { int max_groups; debug_decl(set_var_max_groups, SUDO_DEBUG_UTIL); max_groups = sudo_strtonum(strval, 1, 1024, NULL); if (max_groups <= 0) { sudo_warnx(U_("invalid max groups \"%s\" in %s, line %u"), strval, conf_file, lineno); debug_return_int(false); } sudo_conf_data.settings.max_groups = max_groups; debug_return_int(true); } static int set_var_probe_interfaces(const char *strval, const char *conf_file, unsigned int lineno) { int val = sudo_strtobool(strval); debug_decl(set_var_probe_interfaces, SUDO_DEBUG_UTIL); if (val == -1) { sudo_warnx(U_("invalid value for %s \"%s\" in %s, line %u"), "probe_interfaces", strval, conf_file, lineno); debug_return_int(false); } sudo_conf_data.settings.probe_interfaces = val; debug_return_int(true); } const char * sudo_conf_askpass_path_v1(void) { return sudo_conf_data.path_table[SUDO_CONF_PATH_ASKPASS].pval; } const char * sudo_conf_sesh_path_v1(void) { return sudo_conf_data.path_table[SUDO_CONF_PATH_SESH].pval; } const char * sudo_conf_intercept_path_v1(void) { return sudo_conf_data.path_table[SUDO_CONF_PATH_INTERCEPT].pval; } const char * sudo_conf_noexec_path_v1(void) { return sudo_conf_data.path_table[SUDO_CONF_PATH_NOEXEC].pval; } const char * sudo_conf_plugin_dir_path_v1(void) { return sudo_conf_data.path_table[SUDO_CONF_PATH_PLUGIN_DIR].pval; } const char * sudo_conf_devsearch_path_v1(void) { return sudo_conf_data.path_table[SUDO_CONF_PATH_DEVSEARCH].pval; } int sudo_conf_group_source_v1(void) { return sudo_conf_data.settings.group_source; } int sudo_conf_max_groups_v1(void) { return sudo_conf_data.settings.max_groups; } struct plugin_info_list * sudo_conf_plugins_v1(void) { return &sudo_conf_data.plugins; } struct sudo_conf_debug_list * sudo_conf_debugging_v1(void) { return &sudo_conf_data.debugging; } /* Return the debug files list for a program, or NULL if none. */ struct sudo_conf_debug_file_list * sudo_conf_debug_files_v1(const char *progname) { struct sudo_conf_debug *debug_spec; const char *progbase; debug_decl(sudo_conf_debug_files, SUDO_DEBUG_UTIL); /* Determine basename if program is fully qualified (like for plugins). */ progbase = progname[0] == '/' ? sudo_basename(progname) : progname; /* Convert sudoedit -> sudo. */ if (strcmp(progbase, "sudoedit") == 0) progbase = "sudo"; TAILQ_FOREACH(debug_spec, &sudo_conf_data.debugging, entries) { const char *prog = progbase; if (debug_spec->progname[0] == '/') { /* Match fully-qualified name, if possible. */ prog = progname; } if (strcmp(debug_spec->progname, prog) == 0) debug_return_ptr(&debug_spec->debug_files); } debug_return_ptr(NULL); } bool sudo_conf_developer_mode_v1(void) { /* Developer mode was removed in sudo 1.9.13. */ return false; } bool sudo_conf_disable_coredump_v1(void) { return sudo_conf_data.settings.disable_coredump; } bool sudo_conf_probe_interfaces_v1(void) { return sudo_conf_data.settings.probe_interfaces; } /* * Free dynamically allocated parts of sudo_conf_data and * reset to initial values. */ static void sudo_conf_init(int conf_types) { struct sudo_conf_debug *debug_spec; struct sudo_debug_file *debug_file; struct plugin_info *plugin_info; int i; debug_decl(sudo_conf_init, SUDO_DEBUG_UTIL); /* Free and reset paths. */ if (ISSET(conf_types, SUDO_CONF_PATHS)) { const struct sudo_conf_path_table path_table[] = SUDO_CONF_PATH_INITIALIZER; sudo_conf_clear_paths(); memcpy(sudo_conf_data.path_table, path_table, sizeof(sudo_conf_data.path_table)); } /* Free and reset debug settings. */ if (ISSET(conf_types, SUDO_CONF_DEBUG)) { while ((debug_spec = TAILQ_FIRST(&sudo_conf_data.debugging))) { TAILQ_REMOVE(&sudo_conf_data.debugging, debug_spec, entries); free(debug_spec->progname); while ((debug_file = TAILQ_FIRST(&debug_spec->debug_files))) { TAILQ_REMOVE(&debug_spec->debug_files, debug_file, entries); free(debug_file->debug_file); free(debug_file->debug_flags); free(debug_file); } free(debug_spec); } } /* Free and reset plugins. */ if (ISSET(conf_types, SUDO_CONF_PLUGINS)) { while ((plugin_info = TAILQ_FIRST(&sudo_conf_data.plugins))) { TAILQ_REMOVE(&sudo_conf_data.plugins, plugin_info, entries); free(plugin_info->symbol_name); free(plugin_info->path); if (plugin_info->options != NULL) { for (i = 0; plugin_info->options[i] != NULL; i++) free(plugin_info->options[i]); free(plugin_info->options); } free(plugin_info); } } /* Set initial values. */ if (ISSET(conf_types, SUDO_CONF_SETTINGS)) { const struct sudo_conf_settings settings = SUDO_CONF_SETTINGS_INITIALIZER; sudo_conf_data.settings = settings; } debug_return; } /* * Read in /etc/sudo.conf and populates sudo_conf_data. */ int sudo_conf_read_v1(const char *conf_file, int conf_types) { FILE *fp = NULL; int fd, ret = false; char *prev_locale, *line = NULL; unsigned int conf_lineno = 0; size_t linesize = 0; debug_decl(sudo_conf_read, SUDO_DEBUG_UTIL); if ((prev_locale = setlocale(LC_ALL, NULL)) == NULL) { sudo_warn("setlocale(LC_ALL, NULL)"); debug_return_int(-1); } if ((prev_locale = strdup(prev_locale)) == NULL) { sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory")); debug_return_int(-1); } /* Parse sudo.conf in the "C" locale. */ if (prev_locale[0] != 'C' || prev_locale[1] != '\0') setlocale(LC_ALL, "C"); #ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION if (conf_file == NULL) { struct stat sb; int error; conf_file = _PATH_SUDO_CONF; fd = sudo_secure_open_file(conf_file, ROOT_UID, -1, &sb, &error); if (fd == -1) { switch (error) { case SUDO_PATH_MISSING: /* Root should always be able to read sudo.conf. */ if (errno != ENOENT && geteuid() == ROOT_UID) sudo_warn(U_("unable to open %s"), conf_file); break; case SUDO_PATH_BAD_TYPE: sudo_warnx(U_("%s is not a regular file"), conf_file); break; case SUDO_PATH_WRONG_OWNER: sudo_warnx(U_("%s is owned by uid %u, should be %u"), conf_file, (unsigned int) sb.st_uid, ROOT_UID); break; case SUDO_PATH_WORLD_WRITABLE: sudo_warnx(U_("%s is world writable"), conf_file); break; case SUDO_PATH_GROUP_WRITABLE: sudo_warnx(U_("%s is group writable"), conf_file); break; default: sudo_warnx("%s: internal error, unexpected error %d", __func__, error); break; } goto done; } } else #else if (conf_file == NULL) conf_file = _PATH_SUDO_CONF; #endif /* FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION */ { fd = open(conf_file, O_RDONLY); if (fd == -1) { sudo_warn(U_("unable to open %s"), conf_file); goto done; } } if ((fp = fdopen(fd, "r")) == NULL) { if (errno != ENOENT && geteuid() == ROOT_UID) sudo_warn(U_("unable to open %s"), conf_file); close(fd); goto done; } /* Reset to initial values if necessary. */ if (sudo_conf_data.settings.updated) sudo_conf_init(conf_types); while (sudo_parseln(&line, &linesize, &conf_lineno, fp, 0) != -1) { struct sudo_conf_table *cur; unsigned int i; char *cp; if (*(cp = line) == '\0') continue; /* empty line or comment */ for (i = 0, cur = sudo_conf_table; cur->name != NULL; i++, cur++) { if (strncasecmp(cp, cur->name, cur->namelen) == 0 && isblank((unsigned char)cp[cur->namelen])) { if (ISSET(conf_types, (1 << i))) { cp += cur->namelen; while (isblank((unsigned char)*cp)) cp++; ret = cur->parser(cp, conf_file, conf_lineno); switch (ret) { case true: sudo_conf_data.settings.updated = true; break; case false: break; default: goto done; } } break; } } if (cur->name == NULL) { sudo_debug_printf(SUDO_DEBUG_WARN, "%s: %s:%u: unsupported entry: %s", __func__, conf_file, conf_lineno, line); } } ret = true; done: if (fp != NULL) fclose(fp); free(line); /* Restore locale if needed. */ if (prev_locale[0] != 'C' || prev_locale[1] != '\0') setlocale(LC_ALL, prev_locale); free(prev_locale); debug_return_int(ret); } /* * Used by the sudo_conf regress test to clear compile-time path settings. */ void sudo_conf_clear_paths_v1(void) { struct sudo_conf_path_table *cur; debug_decl(sudo_conf_clear_paths, SUDO_DEBUG_UTIL); for (cur = sudo_conf_data.path_table; cur->pname != NULL; cur++) { if (cur->dynamic) free((char *)cur->pval); cur->pval = NULL; cur->dynamic = false; } }