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-rw-r--r--plugins/sudoers/match.c812
1 files changed, 812 insertions, 0 deletions
diff --git a/plugins/sudoers/match.c b/plugins/sudoers/match.c
new file mode 100644
index 0000000..30a4b10
--- /dev/null
+++ b/plugins/sudoers/match.c
@@ -0,0 +1,812 @@
+/*
+ * SPDX-License-Identifier: ISC
+ *
+ * Copyright (c) 1996, 1998-2005, 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.
+ *
+ * Sponsored in part by the Defense Advanced Research Projects
+ * Agency (DARPA) and Air Force Research Laboratory, Air Force
+ * Materiel Command, USAF, under agreement number F39502-99-1-0512.
+ */
+
+/*
+ * 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 <sys/stat.h>
+#ifdef HAVE_SYS_SYSTEMINFO_H
+# include <sys/systeminfo.h>
+#endif
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#ifdef HAVE_STRINGS_H
+# include <strings.h>
+#endif /* HAVE_STRINGS_H */
+#include <unistd.h>
+#ifdef HAVE_NETGROUP_H
+# include <netgroup.h>
+#else
+# include <netdb.h>
+#endif /* HAVE_NETGROUP_H */
+#include <dirent.h>
+#include <fcntl.h>
+#include <pwd.h>
+#include <grp.h>
+#include <errno.h>
+#ifdef HAVE_FNMATCH
+# include <fnmatch.h>
+#else
+# include <compat/fnmatch.h>
+#endif /* HAVE_FNMATCH */
+
+#include <sudoers.h>
+#include <gram.h>
+
+/*
+ * Check whether user described by pw matches member.
+ * Returns ALLOW, DENY or UNSPEC.
+ */
+int
+user_matches(const struct sudoers_parse_tree *parse_tree,
+ const struct passwd *pw, const struct member *m)
+{
+ const struct sudoers_context *ctx = parse_tree->ctx;
+ const char *lhost = parse_tree->lhost ? parse_tree->lhost : ctx->runas.host;
+ const char *shost = parse_tree->shost ? parse_tree->shost : ctx->runas.shost;
+ int matched = UNSPEC;
+ struct alias *a;
+ debug_decl(user_matches, SUDOERS_DEBUG_MATCH);
+
+ switch (m->type) {
+ case ALL:
+ matched = m->negated ? DENY : ALLOW;
+ break;
+ case NETGROUP:
+ if (netgr_matches(parse_tree->nss, m->name,
+ def_netgroup_tuple ? lhost : NULL,
+ def_netgroup_tuple ? shost : NULL, pw->pw_name) == ALLOW)
+ matched = m->negated ? DENY : ALLOW;
+ break;
+ case USERGROUP:
+ if (usergr_matches(m->name, pw->pw_name, pw) == ALLOW)
+ matched = m->negated ? DENY : ALLOW;
+ break;
+ case ALIAS:
+ if ((a = alias_get(parse_tree, m->name, USERALIAS)) != NULL) {
+ /* XXX */
+ const int rc = userlist_matches(parse_tree, pw, &a->members);
+ if (SPECIFIED(rc)) {
+ if (m->negated) {
+ matched = rc == ALLOW ? DENY : ALLOW;
+ } else {
+ matched = rc;
+ }
+ }
+ alias_put(a);
+ break;
+ }
+ FALLTHROUGH;
+ case WORD:
+ if (userpw_matches(m->name, pw->pw_name, pw) == ALLOW)
+ matched = m->negated ? DENY : ALLOW;
+ break;
+ }
+ debug_return_int(matched);
+}
+
+/*
+ * Check for user described by pw in a list of members.
+ * Returns ALLOW, DENY or UNSPEC.
+ */
+int
+userlist_matches(const struct sudoers_parse_tree *parse_tree,
+ const struct passwd *pw, const struct member_list *list)
+{
+ struct member *m;
+ int matched = UNSPEC;
+ debug_decl(userlist_matches, SUDOERS_DEBUG_MATCH);
+
+ TAILQ_FOREACH_REVERSE(m, list, member_list, entries) {
+ matched = user_matches(parse_tree, pw, m);
+ if (SPECIFIED(matched))
+ break;
+ }
+ debug_return_int(matched);
+}
+
+struct gid_list *
+runas_getgroups(const struct sudoers_context *ctx)
+{
+ const struct passwd *pw;
+ debug_decl(runas_getgroups, SUDOERS_DEBUG_MATCH);
+
+ if (def_preserve_groups) {
+ sudo_gidlist_addref(ctx->user.gid_list);
+ debug_return_ptr(ctx->user.gid_list);
+ }
+
+ /* Only use results from a group db query, not the front end. */
+ pw = ctx->runas.pw ? ctx->runas.pw : ctx->user.pw;
+ debug_return_ptr(sudo_get_gidlist(pw, ENTRY_TYPE_QUERIED));
+}
+
+/*
+ * Check whether the requested runas user matches user_list, the
+ * user portion of a sudoers runaslist. If user_list is NULL, a
+ * list containing runas_default is used.
+ * Returns ALLOW, DENY or UNSPEC.
+ */
+static int
+runas_userlist_matches(const struct sudoers_parse_tree *parse_tree,
+ const struct member_list *user_list, struct member **matching_user)
+{
+ const struct sudoers_context *ctx = parse_tree->ctx;
+ const char *lhost = parse_tree->lhost ? parse_tree->lhost : ctx->runas.host;
+ const char *shost = parse_tree->shost ? parse_tree->shost : ctx->runas.shost;
+ int user_matched = UNSPEC;
+ struct member *m;
+ struct alias *a;
+ debug_decl(runas_userlist_matches, SUDOERS_DEBUG_MATCH);
+
+ TAILQ_FOREACH_REVERSE(m, user_list, member_list, entries) {
+ switch (m->type) {
+ case ALL:
+ user_matched = m->negated ? DENY : ALLOW;
+ break;
+ case NETGROUP:
+ if (netgr_matches(parse_tree->nss, m->name,
+ def_netgroup_tuple ? lhost : NULL,
+ def_netgroup_tuple ? shost : NULL,
+ ctx->runas.pw->pw_name) == ALLOW)
+ user_matched = m->negated ? DENY : ALLOW;
+ break;
+ case USERGROUP:
+ if (usergr_matches(m->name, ctx->runas.pw->pw_name, ctx->runas.pw) == ALLOW)
+ user_matched = m->negated ? DENY : ALLOW;
+ break;
+ case ALIAS:
+ a = alias_get(parse_tree, m->name, RUNASALIAS);
+ if (a != NULL) {
+ const int rc = runas_userlist_matches(parse_tree,
+ &a->members, matching_user);
+ if (SPECIFIED(rc)) {
+ if (m->negated) {
+ user_matched = rc == ALLOW ? DENY : ALLOW;
+ } else {
+ user_matched = rc;
+ }
+ }
+ alias_put(a);
+ break;
+ }
+ FALLTHROUGH;
+ case WORD:
+ if (userpw_matches(m->name, ctx->runas.pw->pw_name, ctx->runas.pw) == ALLOW)
+ user_matched = m->negated ? DENY : ALLOW;
+ break;
+ case MYSELF:
+ /*
+ * Only match a rule with an empty runas user if a group
+ * was specified on the command line without a user _or_
+ * the user specified their own name on the command line.
+ */
+ if ((!ISSET(ctx->settings.flags, RUNAS_USER_SPECIFIED) &&
+ ISSET(ctx->settings.flags, RUNAS_GROUP_SPECIFIED)) ||
+ strcmp(ctx->user.name, ctx->runas.pw->pw_name) == 0)
+ user_matched = m->negated ? DENY : ALLOW;
+ break;
+ }
+ if (SPECIFIED(user_matched)) {
+ if (matching_user != NULL && m->type != ALIAS)
+ *matching_user = m;
+ break;
+ }
+ }
+ debug_return_int(user_matched);
+}
+
+/*
+ * Check whether the requested runas group matches group_list, the
+ * group portion of a sudoers runaslist, or the runas user's groups.
+ * Returns ALLOW, DENY or UNSPEC.
+ */
+static int
+runas_grouplist_matches(const struct sudoers_parse_tree *parse_tree,
+ const struct member_list *group_list, struct member **matching_group)
+{
+ const struct sudoers_context *ctx = parse_tree->ctx;
+ int group_matched = UNSPEC;
+ struct member *m;
+ struct alias *a;
+ debug_decl(runas_grouplist_matches, SUDOERS_DEBUG_MATCH);
+
+ if (group_list != NULL) {
+ TAILQ_FOREACH_REVERSE(m, group_list, member_list, entries) {
+ switch (m->type) {
+ case ALL:
+ group_matched = m->negated ? DENY : ALLOW;
+ break;
+ case ALIAS:
+ a = alias_get(parse_tree, m->name, RUNASALIAS);
+ if (a != NULL) {
+ const int rc = runas_grouplist_matches(parse_tree,
+ &a->members, matching_group);
+ if (SPECIFIED(rc)) {
+ if (m->negated) {
+ group_matched = rc == ALLOW ? DENY : ALLOW;
+ } else {
+ group_matched = rc;
+ }
+ }
+ alias_put(a);
+ break;
+ }
+ FALLTHROUGH;
+ case WORD:
+ if (group_matches(m->name, ctx->runas.gr) == ALLOW)
+ group_matched = m->negated ? DENY : ALLOW;
+ break;
+ }
+ if (SPECIFIED(group_matched)) {
+ if (matching_group != NULL && m->type != ALIAS)
+ *matching_group = m;
+ break;
+ }
+ }
+ }
+ if (!SPECIFIED(group_matched)) {
+ struct gid_list *runas_groups;
+ /*
+ * The runas group was not explicitly allowed by sudoers.
+ * Check whether it is one of the target user's groups.
+ */
+ if (ctx->runas.pw->pw_gid == ctx->runas.gr->gr_gid) {
+ group_matched = ALLOW; /* runas group matches passwd db */
+ } else if ((runas_groups = runas_getgroups(ctx)) != NULL) {
+ int i;
+
+ for (i = 0; i < runas_groups->ngids; i++) {
+ if (runas_groups->gids[i] == ctx->runas.gr->gr_gid) {
+ group_matched = ALLOW; /* matched aux group vector */
+ break;
+ }
+ }
+ sudo_gidlist_delref(runas_groups);
+ }
+ }
+
+ debug_return_int(group_matched);
+}
+
+/*
+ * Check whether the sudoers runaslist, composed of user_list and
+ * group_list, matches the runas user/group requested by the user.
+ * Either (or both) user_list and group_list may be NULL.
+ * If user_list is NULL, a list containing runas_default is used.
+ * Returns ALLOW, DENY or UNSPEC.
+ */
+int
+runaslist_matches(const struct sudoers_parse_tree *parse_tree,
+ const struct member_list *user_list, const struct member_list *group_list,
+ struct member **matching_user, struct member **matching_group)
+{
+ const struct sudoers_context *ctx = parse_tree->ctx;
+ struct member_list _user_list = TAILQ_HEAD_INITIALIZER(_user_list);
+ int user_matched, group_matched = UNSPEC;
+ struct member m_user;
+ debug_decl(runaslist_matches, SUDOERS_DEBUG_MATCH);
+
+ /* If no runas user listed in sudoers, use the default value. */
+ if (user_list == NULL) {
+ m_user.name = def_runas_default;
+ m_user.type = WORD;
+ m_user.negated = false;
+ TAILQ_INSERT_HEAD(&_user_list, &m_user, entries);
+ user_list = &_user_list;
+ matching_user = NULL;
+ }
+
+ user_matched = runas_userlist_matches(parse_tree, user_list, matching_user);
+ if (ISSET(ctx->settings.flags, RUNAS_GROUP_SPECIFIED)) {
+ group_matched = runas_grouplist_matches(parse_tree, group_list,
+ matching_group);
+ }
+
+ if (user_matched == DENY || group_matched == DENY)
+ debug_return_int(DENY);
+ if (user_matched == group_matched || ctx->runas.gr == NULL)
+ debug_return_int(user_matched);
+ debug_return_int(UNSPEC);
+}
+
+/*
+ * Check for lhost and shost in a list of members.
+ * Returns ALLOW, DENY or UNSPEC.
+ */
+static int
+hostlist_matches_int(const struct sudoers_parse_tree *parse_tree,
+ const struct passwd *pw, const char *lhost, const char *shost,
+ const struct member_list *list)
+{
+ struct member *m;
+ int matched = UNSPEC;
+ debug_decl(hostlist_matches, SUDOERS_DEBUG_MATCH);
+
+ TAILQ_FOREACH_REVERSE(m, list, member_list, entries) {
+ matched = host_matches(parse_tree, pw, lhost, shost, m);
+ if (SPECIFIED(matched))
+ break;
+ }
+ debug_return_int(matched);
+}
+
+/*
+ * Check for ctx->runas.host and ctx->runas.shost in a list of members.
+ * Returns ALLOW, DENY or UNSPEC.
+ */
+int
+hostlist_matches(const struct sudoers_parse_tree *parse_tree,
+ const struct passwd *pw, const struct member_list *list)
+{
+ const struct sudoers_context *ctx = parse_tree->ctx;
+ const char *lhost = parse_tree->lhost ? parse_tree->lhost : ctx->runas.host;
+ const char *shost = parse_tree->shost ? parse_tree->shost : ctx->runas.shost;
+
+ return hostlist_matches_int(parse_tree, pw, lhost, shost, list);
+}
+
+/*
+ * Check whether host or shost matches member.
+ * Returns ALLOW, DENY or UNSPEC.
+ */
+int
+host_matches(const struct sudoers_parse_tree *parse_tree,
+ const struct passwd *pw, const char *lhost, const char *shost,
+ const struct member *m)
+{
+ struct alias *a;
+ int ret = UNSPEC;
+ debug_decl(host_matches, SUDOERS_DEBUG_MATCH);
+
+ switch (m->type) {
+ case ALL:
+ ret = m->negated ? DENY : ALLOW;
+ break;
+ case NETGROUP:
+ if (netgr_matches(parse_tree->nss, m->name, lhost, shost,
+ def_netgroup_tuple ? pw->pw_name : NULL) == ALLOW)
+ ret = m->negated ? DENY : ALLOW;
+ break;
+ case NTWKADDR:
+ if (addr_matches(m->name) == ALLOW)
+ ret = m->negated ? DENY : ALLOW;
+ break;
+ case ALIAS:
+ a = alias_get(parse_tree, m->name, HOSTALIAS);
+ if (a != NULL) {
+ /* XXX */
+ const int rc = hostlist_matches_int(parse_tree, pw, lhost,
+ shost, &a->members);
+ if (SPECIFIED(rc)) {
+ if (m->negated) {
+ ret = rc == ALLOW ? DENY : ALLOW;
+ } else {
+ ret = rc;
+ }
+ }
+ alias_put(a);
+ break;
+ }
+ FALLTHROUGH;
+ case WORD:
+ if (hostname_matches(shost, lhost, m->name) == ALLOW)
+ ret = m->negated ? DENY : ALLOW;
+ break;
+ }
+ sudo_debug_printf(SUDO_DEBUG_DEBUG,
+ "host %s (%s) matches sudoers host %s%s: %s", lhost, shost,
+ m->negated ? "!" : "", m->name ? m->name : "ALL",
+ ret == ALLOW ? "ALLOW" : "DENY");
+ debug_return_int(ret);
+}
+
+/*
+ * Check for cmnd and args in a list of members.
+ * Returns ALLOW, DENY or UNSPEC.
+ */
+int
+cmndlist_matches(const struct sudoers_parse_tree *parse_tree,
+ const struct member_list *list, const char *runchroot,
+ struct cmnd_info *info)
+{
+ struct member *m;
+ int matched;
+ debug_decl(cmndlist_matches, SUDOERS_DEBUG_MATCH);
+
+ TAILQ_FOREACH_REVERSE(m, list, member_list, entries) {
+ matched = cmnd_matches(parse_tree, m, runchroot, info);
+ if (SPECIFIED(matched))
+ debug_return_int(matched);
+ }
+ debug_return_int(UNSPEC);
+}
+
+/*
+ * Check cmnd and args.
+ * Returns ALLOW, DENY or UNSPEC.
+ */
+int
+cmnd_matches(const struct sudoers_parse_tree *parse_tree,
+ const struct member *m, const char *runchroot, struct cmnd_info *info)
+{
+ struct alias *a;
+ struct sudo_command *c;
+ int rc, matched = UNSPEC;
+ debug_decl(cmnd_matches, SUDOERS_DEBUG_MATCH);
+
+ switch (m->type) {
+ case ALL:
+ case COMMAND:
+ c = (struct sudo_command *)m->name;
+ if (command_matches(parse_tree->ctx, c->cmnd, c->args, runchroot,
+ info, &c->digests) == ALLOW)
+ matched = m->negated ? DENY : ALLOW;
+ break;
+ case ALIAS:
+ a = alias_get(parse_tree, m->name, CMNDALIAS);
+ if (a != NULL) {
+ rc = cmndlist_matches(parse_tree, &a->members, runchroot, info);
+ if (SPECIFIED(rc)) {
+ if (m->negated) {
+ matched = rc == ALLOW ? DENY : ALLOW;
+ } else {
+ matched = rc;
+ }
+ }
+ alias_put(a);
+ }
+ break;
+ }
+ debug_return_int(matched);
+}
+
+/*
+ * Like cmnd_matches() but only matches against the ALL command.
+ * Returns ALLOW, DENY or UNSPEC.
+ */
+int
+cmnd_matches_all(const struct sudoers_parse_tree *parse_tree,
+ const struct member *m, const char *runchroot, struct cmnd_info *info)
+{
+ const bool negated = m->negated;
+ struct sudo_command *c;
+ int matched = UNSPEC;
+ struct alias *a;
+ debug_decl(cmnd_matches_all, SUDOERS_DEBUG_MATCH);
+
+ switch (m->type) {
+ case ALL:
+ c = (struct sudo_command *)m->name;
+ if (command_matches(parse_tree->ctx, c->cmnd, c->args, runchroot,
+ info, &c->digests) == ALLOW)
+ matched = negated ? DENY : ALLOW;
+ break;
+ case ALIAS:
+ a = alias_get(parse_tree, m->name, CMNDALIAS);
+ if (a != NULL) {
+ TAILQ_FOREACH_REVERSE(m, &a->members, member_list, entries) {
+ matched = cmnd_matches_all(parse_tree, m, runchroot, info);
+ if (SPECIFIED(matched)) {
+ if (negated)
+ matched = matched == ALLOW ? DENY : ALLOW;
+ break;
+ }
+ }
+ alias_put(a);
+ }
+ break;
+ }
+ debug_return_int(matched);
+}
+
+/*
+ * Returns ALLOW if the hostname matches the pattern, else DENY
+ */
+int
+hostname_matches(const char *shost, const char *lhost, const char *pattern)
+{
+ const char *host;
+ int ret;
+ debug_decl(hostname_matches, SUDOERS_DEBUG_MATCH);
+
+ host = strchr(pattern, '.') != NULL ? lhost : shost;
+ ret = DENY;
+ if (has_meta(pattern)) {
+ if (fnmatch(pattern, host, FNM_CASEFOLD) == 0)
+ ret = ALLOW;
+ } else {
+ if (strcasecmp(host, pattern) == 0)
+ ret = ALLOW;
+ }
+ debug_return_int(ret);
+}
+
+/*
+ * Returns ALLOW if the user/uid from sudoers matches the specified user/uid,
+ * else returns DENY.
+ */
+int
+userpw_matches(const char *sudoers_user, const char *user, const struct passwd *pw)
+{
+ const char *errstr;
+ int ret = DENY;
+ uid_t uid;
+ debug_decl(userpw_matches, SUDOERS_DEBUG_MATCH);
+
+ if (pw != NULL && *sudoers_user == '#') {
+ uid = (uid_t) sudo_strtoid(sudoers_user + 1, &errstr);
+ if (errstr == NULL && uid == pw->pw_uid) {
+ ret = ALLOW;
+ goto done;
+ }
+ }
+ if (def_case_insensitive_user) {
+ if (strcasecmp(sudoers_user, user) == 0)
+ ret = ALLOW;
+ } else {
+ if (strcmp(sudoers_user, user) == 0)
+ ret = ALLOW;
+ }
+done:
+ sudo_debug_printf(SUDO_DEBUG_DEBUG|SUDO_DEBUG_LINENO,
+ "user %s matches sudoers user %s: %s",
+ user, sudoers_user, ret == ALLOW ? "ALLOW" : "DENY");
+ debug_return_int(ret);
+}
+
+/*
+ * Returns ALLOW if the group/gid from sudoers matches the specified group/gid,
+ * else returns DENY.
+ */
+int
+group_matches(const char *sudoers_group, const struct group *gr)
+{
+ const char *errstr;
+ int ret = DENY;
+ gid_t gid;
+ debug_decl(group_matches, SUDOERS_DEBUG_MATCH);
+
+ if (*sudoers_group == '#') {
+ gid = (gid_t) sudo_strtoid(sudoers_group + 1, &errstr);
+ if (errstr == NULL && gid == gr->gr_gid) {
+ ret = ALLOW;
+ goto done;
+ }
+ }
+ if (def_case_insensitive_group) {
+ if (strcasecmp(sudoers_group, gr->gr_name) == 0)
+ ret = ALLOW;
+ } else {
+ if (strcmp(sudoers_group, gr->gr_name) == 0)
+ ret = ALLOW;
+ }
+done:
+ sudo_debug_printf(SUDO_DEBUG_DEBUG|SUDO_DEBUG_LINENO,
+ "group %s matches sudoers group %s: %s",
+ gr->gr_name, sudoers_group, ret == ALLOW ? "ALLOW" : "DENY");
+ debug_return_int(ret);
+}
+
+/*
+ * Returns true if the given user belongs to the named group,
+ * else returns false.
+ */
+int
+usergr_matches(const char *group, const char *user, const struct passwd *pw)
+{
+ struct passwd *pw0 = NULL;
+ int ret = DENY;
+ debug_decl(usergr_matches, SUDOERS_DEBUG_MATCH);
+
+ /* Make sure we have a valid usergroup, sudo style */
+ if (*group++ != '%') {
+ sudo_debug_printf(SUDO_DEBUG_DIAG, "user group %s has no leading '%%'",
+ group);
+ goto done;
+ }
+
+ /* Query group plugin for %:name groups. */
+ if (*group == ':' && def_group_plugin) {
+ if (group_plugin_query(user, group + 1, pw) == true)
+ ret = ALLOW;
+ goto done;
+ }
+
+ /* Look up user's primary gid in the passwd file. */
+ if (pw == NULL) {
+ if ((pw0 = sudo_getpwnam(user)) == NULL) {
+ sudo_debug_printf(SUDO_DEBUG_DIAG, "unable to find %s in passwd db",
+ user);
+ goto done;
+ }
+ pw = pw0;
+ }
+
+ if (user_in_group(pw, group)) {
+ ret = ALLOW;
+ goto done;
+ }
+
+ /* Query the group plugin for Unix groups too? */
+ if (def_group_plugin && def_always_query_group_plugin) {
+ if (group_plugin_query(user, group, pw) == true) {
+ ret = ALLOW;
+ goto done;
+ }
+ }
+
+done:
+ if (pw0 != NULL)
+ sudo_pw_delref(pw0);
+
+ sudo_debug_printf(SUDO_DEBUG_DEBUG|SUDO_DEBUG_LINENO,
+ "user %s matches group %s: %s", user, group,
+ ret == ALLOW ? "ALLOW" : "DENY");
+ debug_return_int(ret);
+}
+
+#if defined(HAVE_GETDOMAINNAME) || defined(SI_SRPC_DOMAIN)
+/*
+ * Check the domain for invalid characters.
+ * Linux getdomainname(2) returns (none) if no domain is set.
+ */
+static bool
+valid_domain(const char *domain)
+{
+ const char *cp;
+ debug_decl(valid_domain, SUDOERS_DEBUG_MATCH);
+
+ for (cp = domain; *cp != '\0'; cp++) {
+ /* Check for illegal characters, Linux may use "(none)". */
+ if (*cp == '(' || *cp == ')' || *cp == ',' || *cp == ' ')
+ break;
+ }
+ if (cp == domain || *cp != '\0')
+ debug_return_bool(false);
+ debug_return_bool(true);
+}
+
+/*
+ * Get NIS-style domain name and copy from static storage or NULL if none.
+ */
+const char *
+sudo_getdomainname(void)
+{
+ static char *domain;
+ static bool initialized;
+ debug_decl(sudo_getdomainname, SUDOERS_DEBUG_MATCH);
+
+ if (!initialized) {
+ size_t host_name_max;
+ int rc;
+
+# ifdef _SC_HOST_NAME_MAX
+ host_name_max = (size_t)sysconf(_SC_HOST_NAME_MAX);
+ if (host_name_max == (size_t)-1)
+# endif
+ host_name_max = 255; /* POSIX and historic BSD */
+
+ domain = malloc(host_name_max + 1);
+ if (domain != NULL) {
+ domain[0] = '\0';
+# ifdef SI_SRPC_DOMAIN
+ rc = sysinfo(SI_SRPC_DOMAIN, domain, host_name_max + 1);
+# else
+ rc = getdomainname(domain, host_name_max + 1);
+# endif
+ if (rc == -1 || !valid_domain(domain)) {
+ /* Error or invalid domain name. */
+ free(domain);
+ domain = NULL;
+ }
+ } else {
+ /* XXX - want to pass error back to caller */
+ sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO,
+ "unable to allocate memory");
+ }
+ initialized = true;
+ }
+ debug_return_str(domain);
+}
+#else
+const char *
+sudo_getdomainname(void)
+{
+ debug_decl(sudo_getdomainname, SUDOERS_DEBUG_MATCH);
+ debug_return_ptr(NULL);
+}
+#endif /* HAVE_GETDOMAINNAME || SI_SRPC_DOMAIN */
+
+/*
+ * Returns ALLOW if "host" and "user" belong to the netgroup "netgr",
+ * else return DENY. Either of "lhost", "shost" or "user" may be NULL
+ * in which case that argument is not checked...
+ */
+int
+netgr_matches(const struct sudo_nss *nss, const char *netgr,
+ const char *lhost, const char *shost, const char *user)
+{
+ const char *domain;
+ int ret = DENY;
+ debug_decl(netgr_matches, SUDOERS_DEBUG_MATCH);
+
+ if (!def_use_netgroups) {
+ sudo_debug_printf(SUDO_DEBUG_INFO, "netgroups are disabled");
+ debug_return_int(DENY);
+ }
+
+ /* make sure we have a valid netgroup, sudo style */
+ if (*netgr++ != '+') {
+ sudo_debug_printf(SUDO_DEBUG_DIAG, "netgroup %s has no leading '+'",
+ netgr);
+ debug_return_int(DENY);
+ }
+
+ /* get the domain name (if any) */
+ domain = sudo_getdomainname();
+
+ /* Use nss-specific innetgr() function if available. */
+ if (nss != NULL && nss->innetgr != NULL) {
+ switch (nss->innetgr(nss, netgr, lhost, user, domain)) {
+ case 0:
+ if (lhost != shost) {
+ if (nss->innetgr(nss, netgr, shost, user, domain) == 1)
+ ret = ALLOW;
+ }
+ goto done;
+ case 1:
+ ret = ALLOW;
+ goto done;
+ default:
+ /* Not supported, use system innetgr(3). */
+ break;
+ }
+ }
+
+#ifdef HAVE_INNETGR
+ /* Use system innetgr() function. */
+ if (innetgr(netgr, lhost, user, domain) == 1) {
+ ret = ALLOW;
+ } else if (lhost != shost) {
+ if (innetgr(netgr, shost, user, domain) == 1)
+ ret = ALLOW;
+ }
+#else
+ sudo_debug_printf(SUDO_DEBUG_WARN|SUDO_DEBUG_LINENO,
+ "%s: no system netgroup support", __func__);
+#endif /* HAVE_INNETGR */
+
+done:
+ sudo_debug_printf(SUDO_DEBUG_DEBUG|SUDO_DEBUG_LINENO,
+ "netgroup %s matches (%s|%s, %s, %s): %s", netgr, lhost ? lhost : "",
+ shost ? shost : "", user ? user : "", domain ? domain : "",
+ ret == ALLOW ? "ALLOW" : "DENY");
+
+ debug_return_int(ret);
+}