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-rw-r--r--plugins/sudoers/lookup.c569
1 files changed, 569 insertions, 0 deletions
diff --git a/plugins/sudoers/lookup.c b/plugins/sudoers/lookup.c
new file mode 100644
index 0000000..ffcb23c
--- /dev/null
+++ b/plugins/sudoers/lookup.c
@@ -0,0 +1,569 @@
+/*
+ * SPDX-License-Identifier: ISC
+ *
+ * Copyright (c) 2004-2005, 2007-2023 Todd C. Miller <Todd.Miller@sudo.ws>
+ *
+ * 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 <config.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <pwd.h>
+
+#include <sudoers.h>
+#include <gram.h>
+
+static int
+runas_matches_pw(struct sudoers_parse_tree *parse_tree,
+ const struct cmndspec *cs, const struct passwd *pw)
+{
+ debug_decl(runas_matches_pw, SUDOERS_DEBUG_PARSER);
+
+ if (cs->runasuserlist != NULL)
+ debug_return_int(userlist_matches(parse_tree, pw, cs->runasuserlist));
+
+ if (cs->runasgrouplist == NULL) {
+ /* No explicit runas user or group, use default. */
+ if (userpw_matches(def_runas_default, pw->pw_name, pw) == ALLOW)
+ debug_return_int(ALLOW);
+ }
+ debug_return_int(UNSPEC);
+}
+
+/*
+ * Look up the user in the sudoers parse tree for pseudo-commands like
+ * list, verify and kill.
+ */
+static unsigned int
+sudoers_lookup_pseudo(struct sudo_nss_list *snl, struct sudoers_context *ctx,
+ time_t now, sudoers_lookup_callback_fn_t callback, void *cb_data,
+ int pwflag)
+{
+ char *saved_runchroot;
+ struct passwd *root_pw = NULL;
+ struct sudo_nss *nss;
+ struct cmndspec *cs;
+ struct privilege *priv;
+ struct userspec *us;
+ struct defaults *def;
+ int nopass, match = UNSPEC;
+ unsigned int validated = 0;
+ enum def_tuple pwcheck;
+ debug_decl(sudoers_lookup_pseudo, SUDOERS_DEBUG_PARSER);
+
+ pwcheck = (pwflag == -1) ? never : sudo_defs_table[pwflag].sd_un.tuple;
+ nopass = (pwcheck == never || pwcheck == all) ? true : false;
+
+ if (ctx->runas.list_pw != NULL) {
+ root_pw = sudo_getpwuid(ROOT_UID);
+ if (root_pw == NULL)
+ sudo_warnx(U_("unknown uid %u"), ROOT_UID);
+ } else {
+ SET(validated, FLAG_NO_CHECK);
+ }
+
+ /* Don't use chroot setting for pseudo-commands. */
+ saved_runchroot = def_runchroot;
+ def_runchroot = NULL;
+
+ TAILQ_FOREACH(nss, snl, entries) {
+ if (nss->query(ctx, nss, ctx->user.pw) == -1) {
+ /* The query function should have printed an error message. */
+ SET(validated, VALIDATE_ERROR);
+ break;
+ }
+
+ /*
+ * We have to traverse the policy forwards, not in reverse,
+ * to support the "pwcheck == all" case.
+ */
+ TAILQ_FOREACH(us, &nss->parse_tree->userspecs, entries) {
+ const int user_match = userlist_matches(nss->parse_tree,
+ ctx->user.pw, &us->users);
+ if (user_match != ALLOW) {
+ if (callback != NULL && user_match == DENY) {
+ callback(nss->parse_tree, us, user_match, NULL, UNSPEC,
+ NULL, UNSPEC, UNSPEC, UNSPEC, cb_data);
+ }
+ continue;
+ }
+ TAILQ_FOREACH(priv, &us->privileges, entries) {
+ int priv_nopass = UNSPEC;
+ const int host_match = hostlist_matches(nss->parse_tree,
+ ctx->user.pw, &priv->hostlist);
+ if (host_match != ALLOW) {
+ if (callback != NULL) {
+ callback(nss->parse_tree, us, user_match, priv,
+ host_match, NULL, UNSPEC, UNSPEC, UNSPEC, cb_data);
+ }
+ continue;
+ }
+ TAILQ_FOREACH(def, &priv->defaults, entries) {
+ if (strcmp(def->var, "authenticate") == 0) {
+ priv_nopass = !def->op;
+ break;
+ }
+ }
+ TAILQ_FOREACH(cs, &priv->cmndlist, entries) {
+ int cmnd_match = UNSPEC;
+ int date_match = UNSPEC;
+ int runas_match = UNSPEC;
+
+ if (pwcheck == any) {
+ if (cs->tags.nopasswd == true || priv_nopass == true)
+ nopass = true;
+ } else if (pwcheck == all) {
+ if (cs->tags.nopasswd != true && priv_nopass != true)
+ nopass = false;
+ }
+
+ if (cs->notbefore != UNSPEC) {
+ date_match = now < cs->notbefore ? DENY : ALLOW;
+ }
+ if (cs->notafter != UNSPEC) {
+ date_match = now > cs->notafter ? DENY : ALLOW;
+ }
+ /*
+ * Root can list any user's privileges.
+ * A user may always list their own privileges.
+ */
+ if (ctx->user.uid == 0 || ctx->runas.list_pw == NULL ||
+ ctx->user.uid == ctx->runas.list_pw->pw_uid) {
+ cmnd_match = ALLOW;
+ runas_match = ALLOW;
+ } else if (date_match != DENY) {
+ /*
+ * To list another user's prilileges, the runas
+ * user must match the list user or root.
+ */
+ runas_match = runas_matches_pw(nss->parse_tree, cs,
+ ctx->runas.list_pw);
+ switch (runas_match) {
+ case DENY:
+ break;
+ case ALLOW:
+ /*
+ * RunAs user matches list user.
+ * Match on command "list" or ALL.
+ */
+ cmnd_match = cmnd_matches(nss->parse_tree,
+ cs->cmnd, cs->runchroot, NULL);
+ break;
+ default:
+ /*
+ * RunAs user doesn't match list user.
+ * Only allow listing if the user has
+ * "sudo ALL" for root.
+ */
+ if (root_pw != NULL &&
+ runas_matches_pw(nss->parse_tree, cs,
+ root_pw) == ALLOW) {
+ runas_match = ALLOW;
+ cmnd_match = cmnd_matches_all(nss->parse_tree,
+ cs->cmnd, cs->runchroot, NULL);
+ }
+ break;
+ }
+ }
+ if (callback != NULL) {
+ callback(nss->parse_tree, us, user_match, priv,
+ host_match, cs, date_match, runas_match,
+ cmnd_match, cb_data);
+ }
+ if (SPECIFIED(cmnd_match)) {
+ /*
+ * We take the last match but must process
+ * the entire policy for pwcheck == all.
+ */
+ match = cmnd_match;
+ }
+ }
+ }
+ }
+ if (!sudo_nss_can_continue(nss, match))
+ break;
+ }
+ if (root_pw != NULL)
+ sudo_pw_delref(root_pw);
+ if (match == ALLOW || ctx->user.uid == 0) {
+ /* User has an entry for this host. */
+ SET(validated, VALIDATE_SUCCESS);
+ } else {
+ /* No entry or user is not allowed to list other users. */
+ SET(validated, VALIDATE_FAILURE);
+ }
+ if (pwcheck == always && def_authenticate)
+ SET(validated, FLAG_CHECK_USER);
+ else if (nopass == true)
+ def_authenticate = false;
+
+ /* Restore original def_runchroot. */
+ def_runchroot = saved_runchroot;
+
+ debug_return_uint(validated);
+}
+
+static int
+sudoers_lookup_check(struct sudo_nss *nss, struct sudoers_context *ctx,
+ unsigned int *validated, struct cmnd_info *info, time_t now,
+ sudoers_lookup_callback_fn_t callback, void *cb_data,
+ struct cmndspec **matching_cs, struct defaults_list **defs)
+{
+ struct cmndspec *cs;
+ struct privilege *priv;
+ struct userspec *us;
+ struct member *matching_user;
+ debug_decl(sudoers_lookup_check, SUDOERS_DEBUG_PARSER);
+
+ memset(info, 0, sizeof(*info));
+
+ TAILQ_FOREACH_REVERSE(us, &nss->parse_tree->userspecs, userspec_list, entries) {
+ const int user_match = userlist_matches(nss->parse_tree, ctx->user.pw,
+ &us->users);
+ if (user_match != ALLOW) {
+ if (callback != NULL && user_match == DENY) {
+ callback(nss->parse_tree, us, user_match, NULL, UNSPEC, NULL,
+ UNSPEC, UNSPEC, UNSPEC, cb_data);
+ }
+ continue;
+ }
+ CLR(*validated, FLAG_NO_USER);
+ TAILQ_FOREACH_REVERSE(priv, &us->privileges, privilege_list, entries) {
+ const int host_match = hostlist_matches(nss->parse_tree,
+ ctx->user.pw, &priv->hostlist);
+ if (host_match == ALLOW) {
+ CLR(*validated, FLAG_NO_HOST);
+ } else {
+ if (callback != NULL) {
+ callback(nss->parse_tree, us, user_match, priv, host_match,
+ NULL, UNSPEC, UNSPEC, UNSPEC, cb_data);
+ }
+ continue;
+ }
+ TAILQ_FOREACH_REVERSE(cs, &priv->cmndlist, cmndspec_list, entries) {
+ int cmnd_match = UNSPEC;
+ int date_match = UNSPEC;
+ int runas_match = UNSPEC;
+
+ if (cs->notbefore != UNSPEC) {
+ date_match = now < cs->notbefore ? DENY : ALLOW;
+ }
+ if (cs->notafter != UNSPEC) {
+ date_match = now > cs->notafter ? DENY : ALLOW;
+ }
+ if (date_match != DENY) {
+ matching_user = NULL;
+ runas_match = runaslist_matches(nss->parse_tree,
+ cs->runasuserlist, cs->runasgrouplist, &matching_user,
+ NULL);
+ if (runas_match == ALLOW) {
+ cmnd_match = cmnd_matches(nss->parse_tree, cs->cmnd,
+ cs->runchroot, info);
+ }
+ }
+ if (callback != NULL) {
+ callback(nss->parse_tree, us, user_match, priv, host_match,
+ cs, date_match, runas_match, cmnd_match, cb_data);
+ }
+
+ if (SPECIFIED(cmnd_match)) {
+ /*
+ * If user is running command as themselves,
+ * set ctx->runas.pw = ctx->user.pw.
+ * XXX - hack, want more general solution
+ */
+ if (matching_user && matching_user->type == MYSELF) {
+ sudo_pw_delref(ctx->runas.pw);
+ sudo_pw_addref(ctx->user.pw);
+ ctx->runas.pw = ctx->user.pw;
+ }
+ *matching_cs = cs;
+ *defs = &priv->defaults;
+ sudo_debug_printf(SUDO_DEBUG_DEBUG|SUDO_DEBUG_LINENO,
+ "userspec matched @ %s:%d:%d: %s",
+ us->file ? us->file : "???", us->line, us->column,
+ cmnd_match ? "allowed" : "denied");
+ debug_return_int(cmnd_match);
+ }
+ free(info->cmnd_path);
+ memset(info, 0, sizeof(*info));
+ }
+ }
+ }
+ debug_return_int(UNSPEC);
+}
+
+/*
+ * Apply cmndspec-specific settings including SELinux role/type,
+ * Solaris privs, and command tags.
+ */
+static bool
+apply_cmndspec(struct sudoers_context *ctx, struct cmndspec *cs)
+{
+ debug_decl(apply_cmndspec, SUDOERS_DEBUG_PARSER);
+
+ if (cs != NULL) {
+#ifdef HAVE_SELINUX
+ /* Set role and type if not specified on command line. */
+ if (ctx->runas.role == NULL) {
+ if (cs->role != NULL) {
+ ctx->runas.role = strdup(cs->role);
+ if (ctx->runas.role == NULL) {
+ sudo_warnx(U_("%s: %s"), __func__,
+ U_("unable to allocate memory"));
+ debug_return_bool(false);
+ }
+ } else {
+ ctx->runas.role = def_role;
+ def_role = NULL;
+ }
+ if (ctx->runas.role != NULL) {
+ sudo_debug_printf(SUDO_DEBUG_INFO|SUDO_DEBUG_LINENO,
+ "ctx->runas.role -> %s", ctx->runas.role);
+ }
+ }
+ if (ctx->runas.type == NULL) {
+ if (cs->type != NULL) {
+ ctx->runas.type = strdup(cs->type);
+ if (ctx->runas.type == NULL) {
+ sudo_warnx(U_("%s: %s"), __func__,
+ U_("unable to allocate memory"));
+ debug_return_bool(false);
+ }
+ } else {
+ ctx->runas.type = def_type;
+ def_type = NULL;
+ }
+ if (ctx->runas.type != NULL) {
+ sudo_debug_printf(SUDO_DEBUG_INFO|SUDO_DEBUG_LINENO,
+ "ctx->runas.type -> %s", ctx->runas.type);
+ }
+ }
+#endif /* HAVE_SELINUX */
+#ifdef HAVE_APPARMOR
+ /* Set AppArmor profile, if specified */
+ if (cs->apparmor_profile != NULL) {
+ ctx->runas.apparmor_profile = strdup(cs->apparmor_profile);
+ if (ctx->runas.apparmor_profile == NULL) {
+ sudo_warnx(U_("%s: %s"), __func__,
+ U_("unable to allocate memory"));
+ debug_return_bool(false);
+ }
+ } else {
+ ctx->runas.apparmor_profile = def_apparmor_profile;
+ def_apparmor_profile = NULL;
+ }
+ if (ctx->runas.apparmor_profile != NULL) {
+ sudo_debug_printf(SUDO_DEBUG_INFO|SUDO_DEBUG_LINENO,
+ "ctx->runas.apparmor_profile -> %s", ctx->runas.apparmor_profile);
+ }
+#endif
+#ifdef HAVE_PRIV_SET
+ /* Set Solaris privilege sets */
+ if (ctx->runas.privs == NULL) {
+ if (cs->privs != NULL) {
+ ctx->runas.privs = strdup(cs->privs);
+ if (ctx->runas.privs == NULL) {
+ sudo_warnx(U_("%s: %s"), __func__,
+ U_("unable to allocate memory"));
+ debug_return_bool(false);
+ }
+ } else {
+ ctx->runas.privs = def_privs;
+ def_privs = NULL;
+ }
+ if (ctx->runas.privs != NULL) {
+ sudo_debug_printf(SUDO_DEBUG_INFO|SUDO_DEBUG_LINENO,
+ "ctx->runas.privs -> %s", ctx->runas.privs);
+ }
+ }
+ if (ctx->runas.limitprivs == NULL) {
+ if (cs->limitprivs != NULL) {
+ ctx->runas.limitprivs = strdup(cs->limitprivs);
+ if (ctx->runas.limitprivs == NULL) {
+ sudo_warnx(U_("%s: %s"), __func__,
+ U_("unable to allocate memory"));
+ debug_return_bool(false);
+ }
+ } else {
+ ctx->runas.limitprivs = def_limitprivs;
+ def_limitprivs = NULL;
+ }
+ if (ctx->runas.limitprivs != NULL) {
+ sudo_debug_printf(SUDO_DEBUG_INFO|SUDO_DEBUG_LINENO,
+ "ctx->runas.limitprivs -> %s", ctx->runas.limitprivs);
+ }
+ }
+#endif /* HAVE_PRIV_SET */
+ if (cs->timeout > 0) {
+ def_command_timeout = cs->timeout;
+ sudo_debug_printf(SUDO_DEBUG_INFO|SUDO_DEBUG_LINENO,
+ "def_command_timeout -> %d", def_command_timeout);
+ }
+ if (cs->runcwd != NULL) {
+ free(def_runcwd);
+ def_runcwd = strdup(cs->runcwd);
+ if (def_runcwd == NULL) {
+ sudo_warnx(U_("%s: %s"), __func__,
+ U_("unable to allocate memory"));
+ debug_return_bool(false);
+ }
+ sudo_debug_printf(SUDO_DEBUG_INFO|SUDO_DEBUG_LINENO,
+ "def_runcwd -> %s", def_runcwd);
+ }
+ if (cs->runchroot != NULL) {
+ free(def_runchroot);
+ def_runchroot = strdup(cs->runchroot);
+ if (def_runchroot == NULL) {
+ sudo_warnx(U_("%s: %s"), __func__,
+ U_("unable to allocate memory"));
+ debug_return_bool(false);
+ }
+ sudo_debug_printf(SUDO_DEBUG_INFO|SUDO_DEBUG_LINENO,
+ "def_runchroot -> %s", def_runchroot);
+ }
+ if (cs->tags.nopasswd != UNSPEC) {
+ def_authenticate = !cs->tags.nopasswd;
+ sudo_debug_printf(SUDO_DEBUG_INFO|SUDO_DEBUG_LINENO,
+ "def_authenticate -> %s", def_authenticate ? "true" : "false");
+ }
+ if (cs->tags.noexec != UNSPEC) {
+ def_noexec = cs->tags.noexec;
+ sudo_debug_printf(SUDO_DEBUG_INFO|SUDO_DEBUG_LINENO,
+ "def_noexec -> %s", def_noexec ? "true" : "false");
+ }
+ if (cs->tags.intercept != UNSPEC) {
+ def_intercept = cs->tags.intercept;
+ sudo_debug_printf(SUDO_DEBUG_INFO|SUDO_DEBUG_LINENO,
+ "def_intercept -> %s", def_intercept ? "true" : "false");
+ }
+ if (cs->tags.setenv != UNSPEC) {
+ def_setenv = cs->tags.setenv;
+ sudo_debug_printf(SUDO_DEBUG_INFO|SUDO_DEBUG_LINENO,
+ "def_setenv -> %s", def_setenv ? "true" : "false");
+ }
+ if (cs->tags.log_input != UNSPEC) {
+ def_log_input = cs->tags.log_input;
+ cb_log_input(ctx, NULL, 0, 0, NULL, cs->tags.log_input);
+ sudo_debug_printf(SUDO_DEBUG_INFO|SUDO_DEBUG_LINENO,
+ "def_log_input -> %s", def_log_input ? "true" : "false");
+ }
+ if (cs->tags.log_output != UNSPEC) {
+ def_log_output = cs->tags.log_output;
+ cb_log_output(ctx, NULL, 0, 0, NULL, cs->tags.log_output);
+ sudo_debug_printf(SUDO_DEBUG_INFO|SUDO_DEBUG_LINENO,
+ "def_log_output -> %s", def_log_output ? "true" : "false");
+ }
+ if (cs->tags.send_mail != UNSPEC) {
+ if (cs->tags.send_mail) {
+ def_mail_all_cmnds = true;
+ sudo_debug_printf(SUDO_DEBUG_INFO|SUDO_DEBUG_LINENO,
+ "def_mail_all_cmnds -> true");
+ } else {
+ def_mail_all_cmnds = false;
+ def_mail_always = false;
+ def_mail_no_perms = false;
+ sudo_debug_printf(SUDO_DEBUG_INFO|SUDO_DEBUG_LINENO,
+ "def_mail_all_cmnds -> false, def_mail_always -> false, "
+ "def_mail_no_perms -> false");
+ }
+ }
+ if (cs->tags.follow != UNSPEC) {
+ def_sudoedit_follow = cs->tags.follow;
+ sudo_debug_printf(SUDO_DEBUG_INFO|SUDO_DEBUG_LINENO,
+ "def_sudoedit_follow -> %s", def_sudoedit_follow ? "true" : "false");
+ }
+ }
+
+ debug_return_bool(true);
+}
+
+/*
+ * Look up the user in the sudoers parse tree and check to see if they are
+ * allowed to run the specified command on this host as the target user.
+ */
+unsigned int
+sudoers_lookup(struct sudo_nss_list *snl, struct sudoers_context *ctx,
+ time_t now, sudoers_lookup_callback_fn_t callback, void *cb_data,
+ int *cmnd_status, int pwflag)
+{
+ struct defaults_list *defs = NULL;
+ struct sudoers_parse_tree *parse_tree = NULL;
+ struct cmndspec *cs = NULL;
+ struct sudo_nss *nss;
+ struct cmnd_info info;
+ unsigned int validated = FLAG_NO_USER | FLAG_NO_HOST;
+ int m, match = UNSPEC;
+ debug_decl(sudoers_lookup, SUDOERS_DEBUG_PARSER);
+
+ /*
+ * Special case checking the "validate", "list" and "kill" pseudo-commands.
+ */
+ if (pwflag) {
+ debug_return_uint(sudoers_lookup_pseudo(snl, ctx, now, callback,
+ cb_data, pwflag));
+ }
+
+ /* Need to be runas user while stat'ing things. */
+ if (!set_perms(ctx, PERM_RUNAS))
+ debug_return_uint(validated);
+
+ /* Query each sudoers source and check the user. */
+ TAILQ_FOREACH(nss, snl, entries) {
+ if (nss->query(ctx, nss, ctx->user.pw) == -1) {
+ /* The query function should have printed an error message. */
+ SET(validated, VALIDATE_ERROR);
+ break;
+ }
+
+ m = sudoers_lookup_check(nss, ctx, &validated, &info, now, callback,
+ cb_data, &cs, &defs);
+ if (SPECIFIED(m)) {
+ match = m;
+ parse_tree = nss->parse_tree;
+ }
+
+ if (!sudo_nss_can_continue(nss, m))
+ break;
+ }
+ if (SPECIFIED(match)) {
+ if (info.cmnd_path != NULL) {
+ /* Update cmnd, cmnd_stat, cmnd_status from matching entry. */
+ free(ctx->user.cmnd);
+ ctx->user.cmnd = info.cmnd_path;
+ if (ctx->user.cmnd_stat != NULL)
+ *ctx->user.cmnd_stat = info.cmnd_stat;
+ *cmnd_status = info.status;
+ }
+ if (defs != NULL)
+ (void)update_defaults(ctx, parse_tree, defs, SETDEF_GENERIC, false);
+ if (!apply_cmndspec(ctx, cs))
+ SET(validated, VALIDATE_ERROR);
+ else if (match == ALLOW)
+ SET(validated, VALIDATE_SUCCESS);
+ else
+ SET(validated, VALIDATE_FAILURE);
+ }
+ if (!restore_perms())
+ SET(validated, VALIDATE_ERROR);
+ debug_return_uint(validated);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-24 15:26:35 +0000