sudo/plugins/sudoers/display.c

656 lines
19 KiB
C

/*
* SPDX-License-Identifier: ISC
*
* Copyright (c) 2004-2005, 2007-2024 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 <sys/stat.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <ctype.h>
#include <pwd.h>
#include <sudoers.h>
#include <sudo_lbuf.h>
#include <gram.h>
static int
display_priv_short(const struct sudoers_parse_tree *parse_tree,
const struct passwd *pw, const struct userspec *us, struct sudo_lbuf *lbuf)
{
struct privilege *priv;
int nfound = 0;
debug_decl(display_priv_short, SUDOERS_DEBUG_PARSER);
TAILQ_FOREACH(priv, &us->privileges, entries) {
struct cmndspec *cs;
struct cmndtag tags;
if (hostlist_matches(parse_tree, pw, &priv->hostlist) != ALLOW)
continue;
sudoers_defaults_list_to_tags(&priv->defaults, &tags);
TAILQ_FOREACH(cs, &priv->cmndlist, entries) {
struct cmndspec *prev_cs = TAILQ_PREV(cs, cmndspec_list, entries);
if (prev_cs == NULL || RUNAS_CHANGED(cs, prev_cs)) {
struct member *m;
/* Start new line, first entry or RunAs changed. */
if (prev_cs != NULL)
sudo_lbuf_append(lbuf, "\n");
sudo_lbuf_append(lbuf, " (");
if (cs->runasuserlist != NULL) {
TAILQ_FOREACH(m, cs->runasuserlist, entries) {
if (m != TAILQ_FIRST(cs->runasuserlist))
sudo_lbuf_append(lbuf, ", ");
sudoers_format_member(lbuf, parse_tree, m, ", ",
RUNASALIAS);
}
} else if (cs->runasgrouplist == NULL) {
sudo_lbuf_append(lbuf, "%s", def_runas_default);
} else {
sudo_lbuf_append(lbuf, "%s", pw->pw_name);
}
if (cs->runasgrouplist != NULL) {
sudo_lbuf_append(lbuf, " : ");
TAILQ_FOREACH(m, cs->runasgrouplist, entries) {
if (m != TAILQ_FIRST(cs->runasgrouplist))
sudo_lbuf_append(lbuf, ", ");
sudoers_format_member(lbuf, parse_tree, m, ", ",
RUNASALIAS);
}
}
sudo_lbuf_append(lbuf, ") ");
sudoers_format_cmndspec(lbuf, parse_tree, cs, NULL,
tags, true);
} else {
/* Continue existing line. */
sudo_lbuf_append(lbuf, ", ");
sudoers_format_cmndspec(lbuf, parse_tree, cs, prev_cs,
tags, true);
}
nfound++;
}
sudo_lbuf_append(lbuf, "\n");
}
debug_return_int(nfound);
}
/*
* Compare the current cmndspec with the previous one to determine
* whether we need to start a new long entry for "sudo -ll".
* Returns true if we should start a new long entry, else false.
*/
static bool
new_long_entry(const struct cmndspec *cs, const struct cmndspec *prev_cs)
{
debug_decl(new_long_entry, SUDOERS_DEBUG_PARSER);
if (prev_cs == NULL)
debug_return_bool(true);
if (RUNAS_CHANGED(cs, prev_cs) || TAGS_CHANGED(prev_cs->tags, cs->tags))
debug_return_bool(true);
if (cs->privs && (!prev_cs->privs || strcmp(cs->privs, prev_cs->privs) != 0))
debug_return_bool(true);
if (cs->limitprivs && (!prev_cs->limitprivs || strcmp(cs->limitprivs, prev_cs->limitprivs) != 0))
debug_return_bool(true);
if (cs->role && (!prev_cs->role || strcmp(cs->role, prev_cs->role) != 0))
debug_return_bool(true);
if (cs->type && (!prev_cs->type || strcmp(cs->type, prev_cs->type) != 0))
debug_return_bool(true);
if (cs->apparmor_profile && (!prev_cs->apparmor_profile || strcmp(cs->apparmor_profile, prev_cs->apparmor_profile) != 0))
debug_return_bool(true);
if (cs->runchroot && (!prev_cs->runchroot || strcmp(cs->runchroot, prev_cs->runchroot) != 0))
debug_return_bool(true);
if (cs->runcwd && (!prev_cs->runcwd || strcmp(cs->runcwd, prev_cs->runcwd) != 0))
debug_return_bool(true);
if (cs->timeout != prev_cs->timeout)
debug_return_bool(true);
if (cs->notbefore != prev_cs->notbefore)
debug_return_bool(true);
if (cs->notafter != prev_cs->notafter)
debug_return_bool(true);
debug_return_bool(false);
}
static void
display_cmndspec_long(const struct sudoers_parse_tree *parse_tree,
const struct passwd *pw, const struct userspec *us,
const struct privilege *priv, const struct cmndspec *cs,
const struct cmndspec *prev_cs, struct sudo_lbuf *lbuf)
{
const struct defaults *d;
const struct member *m;
debug_decl(display_cmndspec_long, SUDOERS_DEBUG_PARSER);
if (new_long_entry(cs, prev_cs)) {
unsigned int olen;
if (prev_cs != NULL)
sudo_lbuf_append(lbuf, "\n");
if (priv->ldap_role != NULL) {
sudo_lbuf_append(lbuf, _("LDAP Role: %s\n"),
priv->ldap_role);
} else {
sudo_lbuf_append(lbuf, _("Sudoers entry: %s\n"),
us->file);
}
sudo_lbuf_append(lbuf, "%s", _(" RunAsUsers: "));
if (cs->runasuserlist != NULL) {
TAILQ_FOREACH(m, cs->runasuserlist, entries) {
if (m != TAILQ_FIRST(cs->runasuserlist))
sudo_lbuf_append(lbuf, ", ");
sudoers_format_member(lbuf, parse_tree, m, ", ",
RUNASALIAS);
}
} else if (cs->runasgrouplist == NULL) {
sudo_lbuf_append(lbuf, "%s", def_runas_default);
} else {
sudo_lbuf_append(lbuf, "%s", pw->pw_name);
}
sudo_lbuf_append(lbuf, "\n");
if (cs->runasgrouplist != NULL) {
sudo_lbuf_append(lbuf, "%s", _(" RunAsGroups: "));
TAILQ_FOREACH(m, cs->runasgrouplist, entries) {
if (m != TAILQ_FIRST(cs->runasgrouplist))
sudo_lbuf_append(lbuf, ", ");
sudoers_format_member(lbuf, parse_tree, m, ", ",
RUNASALIAS);
}
sudo_lbuf_append(lbuf, "\n");
}
olen = lbuf->len;
sudo_lbuf_append(lbuf, "%s", _(" Options: "));
TAILQ_FOREACH(d, &priv->defaults, entries) {
sudoers_format_default(lbuf, d);
sudo_lbuf_append(lbuf, ", ");
}
if (TAG_SET(cs->tags.setenv))
sudo_lbuf_append(lbuf, "%ssetenv, ", cs->tags.setenv ? "" : "!");
if (TAG_SET(cs->tags.noexec))
sudo_lbuf_append(lbuf, "%snoexec, ", cs->tags.noexec ? "" : "!");
if (TAG_SET(cs->tags.intercept))
sudo_lbuf_append(lbuf, "%sintercept, ", cs->tags.intercept ? "" : "!");
if (TAG_SET(cs->tags.nopasswd))
sudo_lbuf_append(lbuf, "%sauthenticate, ", cs->tags.nopasswd ? "!" : "");
if (TAG_SET(cs->tags.log_input))
sudo_lbuf_append(lbuf, "%slog_input, ", cs->tags.log_input ? "" : "!");
if (TAG_SET(cs->tags.log_output))
sudo_lbuf_append(lbuf, "%slog_output, ", cs->tags.log_output ? "" : "!");
if (lbuf->buf[lbuf->len - 2] == ',') {
lbuf->len -= 2; /* remove trailing ", " */
sudo_lbuf_append(lbuf, "\n");
} else {
lbuf->len = olen; /* no options */
}
if (cs->apparmor_profile != NULL) {
sudo_lbuf_append(lbuf, " ApparmorProfile: %s\n",
cs->apparmor_profile);
}
if (cs->privs != NULL)
sudo_lbuf_append(lbuf, " Privs: %s\n", cs->privs);
if (cs->limitprivs != NULL)
sudo_lbuf_append(lbuf, " Limitprivs: %s\n", cs->limitprivs);
if (cs->role != NULL)
sudo_lbuf_append(lbuf, " Role: %s\n", cs->role);
if (cs->type != NULL)
sudo_lbuf_append(lbuf, " Type: %s\n", cs->type);
if (cs->runchroot != NULL)
sudo_lbuf_append(lbuf, " Chroot: %s\n", cs->runchroot);
if (cs->runcwd != NULL)
sudo_lbuf_append(lbuf, " Cwd: %s\n", cs->runcwd);
if (cs->timeout > 0) {
char numbuf[STRLEN_MAX_SIGNED(int) + 1];
(void)snprintf(numbuf, sizeof(numbuf), "%d", cs->timeout);
sudo_lbuf_append(lbuf, " Timeout: %s\n", numbuf);
}
if (cs->notbefore != UNSPEC) {
char buf[sizeof("CCYYMMDDHHMMSSZ")] = "";
struct tm gmt;
size_t len;
if (gmtime_r(&cs->notbefore, &gmt) != NULL) {
len = strftime(buf, sizeof(buf), "%Y%m%d%H%M%SZ", &gmt);
if (len != 0 && buf[sizeof(buf) - 1] == '\0')
sudo_lbuf_append(lbuf, " NotBefore: %s\n", buf);
}
}
if (cs->notafter != UNSPEC) {
char buf[sizeof("CCYYMMDDHHMMSSZ")] = "";
struct tm gmt;
size_t len;
if (gmtime_r(&cs->notafter, &gmt) != NULL) {
len = strftime(buf, sizeof(buf), "%Y%m%d%H%M%SZ", &gmt);
if (len != 0 && buf[sizeof(buf) - 1] == '\0')
sudo_lbuf_append(lbuf, " NotAfter: %s\n", buf);
}
}
sudo_lbuf_append(lbuf, "%s", _(" Commands:\n"));
}
sudo_lbuf_append(lbuf, "\t");
sudoers_format_member(lbuf, parse_tree, cs->cmnd, "\n\t",
CMNDALIAS);
sudo_lbuf_append(lbuf, "\n");
debug_return;
}
static int
display_priv_long(const struct sudoers_parse_tree *parse_tree,
const struct passwd *pw, const struct userspec *us, struct sudo_lbuf *lbuf)
{
const struct privilege *priv;
int nfound = 0;
debug_decl(display_priv_long, SUDOERS_DEBUG_PARSER);
TAILQ_FOREACH(priv, &us->privileges, entries) {
const struct cmndspec *cs, *prev_cs;
if (hostlist_matches(parse_tree, pw, &priv->hostlist) != ALLOW)
continue;
prev_cs = NULL;
sudo_lbuf_append(lbuf, "\n");
TAILQ_FOREACH(cs, &priv->cmndlist, entries) {
display_cmndspec_long(parse_tree, pw, us, priv, cs, prev_cs,
lbuf);
prev_cs = cs;
nfound++;
}
}
debug_return_int(nfound);
}
static int
sudo_display_userspecs(struct sudoers_parse_tree *parse_tree,
const struct passwd *pw, struct sudo_lbuf *lbuf, bool verbose)
{
const struct userspec *us;
int nfound = 0;
debug_decl(sudo_display_userspecs, SUDOERS_DEBUG_PARSER);
TAILQ_FOREACH(us, &parse_tree->userspecs, entries) {
if (userlist_matches(parse_tree, pw, &us->users) != ALLOW)
continue;
if (verbose)
nfound += display_priv_long(parse_tree, pw, us, lbuf);
else
nfound += display_priv_short(parse_tree, pw, us, lbuf);
}
if (sudo_lbuf_error(lbuf))
debug_return_int(-1);
debug_return_int(nfound);
}
/*
* Display matching Defaults entries for the given user on this host.
*/
static int
display_defaults(const struct sudoers_parse_tree *parse_tree,
const struct passwd *pw, struct sudo_lbuf *lbuf)
{
const struct defaults *d;
const char *prefix;
int nfound = 0;
debug_decl(display_defaults, SUDOERS_DEBUG_PARSER);
if (lbuf->len == 0 || isspace((unsigned char)lbuf->buf[lbuf->len - 1]))
prefix = " ";
else
prefix = ", ";
TAILQ_FOREACH(d, &parse_tree->defaults, entries) {
switch (d->type) {
case DEFAULTS_HOST:
if (hostlist_matches(parse_tree, pw, &d->binding->members) != ALLOW)
continue;
break;
case DEFAULTS_USER:
if (userlist_matches(parse_tree, pw, &d->binding->members) != ALLOW)
continue;
break;
case DEFAULTS_RUNAS:
case DEFAULTS_CMND:
continue;
}
sudo_lbuf_append(lbuf, "%s", prefix);
sudoers_format_default(lbuf, d);
prefix = ", ";
nfound++;
}
if (sudo_lbuf_error(lbuf))
debug_return_int(-1);
debug_return_int(nfound);
}
/*
* Display Defaults entries of the given type.
*/
static int
display_bound_defaults_by_type(const struct sudoers_parse_tree *parse_tree,
int deftype, struct sudo_lbuf *lbuf)
{
const struct defaults *d;
const struct defaults_binding *binding = NULL;
const struct member *m;
const char *dsep;
short atype;
int nfound = 0;
debug_decl(display_bound_defaults_by_type, SUDOERS_DEBUG_PARSER);
switch (deftype) {
case DEFAULTS_HOST:
atype = HOSTALIAS;
dsep = "@";
break;
case DEFAULTS_USER:
atype = USERALIAS;
dsep = ":";
break;
case DEFAULTS_RUNAS:
atype = RUNASALIAS;
dsep = ">";
break;
case DEFAULTS_CMND:
atype = CMNDALIAS;
dsep = "!";
break;
default:
debug_return_int(-1);
}
TAILQ_FOREACH(d, &parse_tree->defaults, entries) {
if (d->type != deftype)
continue;
nfound++;
if (binding != d->binding) {
binding = d->binding;
if (nfound != 1)
sudo_lbuf_append(lbuf, "\n");
sudo_lbuf_append(lbuf, " Defaults%s", dsep);
TAILQ_FOREACH(m, &binding->members, entries) {
if (m != TAILQ_FIRST(&binding->members))
sudo_lbuf_append(lbuf, ", ");
sudoers_format_member(lbuf, parse_tree, m, ", ", atype);
}
sudo_lbuf_append(lbuf, " ");
} else
sudo_lbuf_append(lbuf, ", ");
sudoers_format_default(lbuf, d);
}
if (sudo_lbuf_error(lbuf))
debug_return_int(-1);
debug_return_int(nfound);
}
/*
* Display Defaults entries that are per-runas or per-command
*/
static int
display_bound_defaults(const struct sudoers_parse_tree *parse_tree,
const struct passwd *pw, struct sudo_lbuf *lbuf)
{
int nfound = 0;
debug_decl(display_bound_defaults, SUDOERS_DEBUG_PARSER);
/* XXX - should only print ones that match what the user can do. */
nfound += display_bound_defaults_by_type(parse_tree, DEFAULTS_RUNAS,
lbuf);
nfound += display_bound_defaults_by_type(parse_tree, DEFAULTS_CMND,
lbuf);
if (sudo_lbuf_error(lbuf))
debug_return_int(-1);
debug_return_int(nfound);
}
static int
output(const char *buf)
{
struct sudo_conv_message msg;
struct sudo_conv_reply repl;
debug_decl(output, SUDOERS_DEBUG_NSS);
/* Call conversation function */
memset(&msg, 0, sizeof(msg));
msg.msg_type = SUDO_CONV_INFO_MSG;
msg.msg = buf;
memset(&repl, 0, sizeof(repl));
if (sudo_conv(1, &msg, &repl, NULL) == -1)
debug_return_int(0);
debug_return_int((int)strlen(buf));
}
/*
* Print out privileges for the specified user.
* Returns true on success or -1 on error.
*/
int
display_privs(struct sudoers_context *ctx, const struct sudo_nss_list *snl,
struct passwd *pw, int verbose)
{
const struct sudo_nss *nss;
struct sudo_lbuf def_buf, priv_buf;
int cols, count, n;
unsigned int olen;
struct stat sb;
debug_decl(display_privs, SUDOERS_DEBUG_PARSER);
if (verbose < 0) {
/* Nothing to display. */
debug_return_int(true);
}
cols = ctx->user.cols;
if (fstat(STDOUT_FILENO, &sb) == 0 && S_ISFIFO(sb.st_mode))
cols = 0;
sudo_lbuf_init(&def_buf, output, 4, NULL, cols);
sudo_lbuf_init(&priv_buf, output, 8, NULL, cols);
sudo_lbuf_append(&def_buf, _("Matching Defaults entries for %s on %s:\n"),
pw->pw_name, ctx->runas.shost);
count = 0;
TAILQ_FOREACH(nss, snl, entries) {
n = display_defaults(nss->parse_tree, pw, &def_buf);
if (n == -1)
goto bad;
count += n;
}
if (count != 0) {
sudo_lbuf_append(&def_buf, "\n\n");
} else {
/* Undo Defaults header. */
def_buf.len = 0;
}
/* Display Runas and Cmnd-specific defaults. */
olen = def_buf.len;
sudo_lbuf_append(&def_buf, _("Runas and Command-specific defaults for %s:\n"),
pw->pw_name);
count = 0;
TAILQ_FOREACH(nss, snl, entries) {
n = display_bound_defaults(nss->parse_tree, pw, &def_buf);
if (n == -1)
goto bad;
count += n;
}
if (count != 0) {
sudo_lbuf_append(&def_buf, "\n\n");
} else {
/* Undo Defaults header. */
def_buf.len = olen;
}
/* Display privileges from all sources. */
sudo_lbuf_append(&priv_buf,
_("User %s may run the following commands on %s:\n"),
pw->pw_name, ctx->runas.shost);
count = 0;
TAILQ_FOREACH(nss, snl, entries) {
if (nss->query(ctx, nss, pw) != -1) {
n = sudo_display_userspecs(nss->parse_tree, pw, &priv_buf,
verbose);
if (n == -1)
goto bad;
count += n;
}
}
if (count == 0) {
def_buf.len = 0;
priv_buf.len = 0;
sudo_lbuf_append(&priv_buf,
_("User %s is not allowed to run sudo on %s.\n"),
pw->pw_name, ctx->runas.shost);
}
if (sudo_lbuf_error(&def_buf) || sudo_lbuf_error(&priv_buf))
goto bad;
sudo_lbuf_print(&def_buf);
sudo_lbuf_print(&priv_buf);
sudo_lbuf_destroy(&def_buf);
sudo_lbuf_destroy(&priv_buf);
debug_return_int(true);
bad:
sudo_lbuf_destroy(&def_buf);
sudo_lbuf_destroy(&priv_buf);
debug_return_int(-1);
}
static int
display_cmnd_check(struct sudoers_context *ctx,
const struct sudoers_parse_tree *parse_tree, const struct passwd *pw,
time_t now, struct sudoers_match_info *match_info)
{
int host_match, runas_match, cmnd_match = UNSPEC;
char *saved_user_cmnd, *saved_user_base;
const struct privilege *priv;
const struct userspec *us;
const struct cmndspec *cs;
debug_decl(display_cmnd_check, SUDOERS_DEBUG_PARSER);
/*
* For "sudo -l command", ctx->user.cmnd is "list" and the actual
* command we are checking is in ctx->user.cmnd_list.
*/
saved_user_cmnd = ctx->user.cmnd;
saved_user_base = ctx->user.cmnd_base;
ctx->user.cmnd = ctx->user.cmnd_list;
ctx->user.cmnd_base = sudo_basename(ctx->user.cmnd);
TAILQ_FOREACH_REVERSE(us, &parse_tree->userspecs, userspec_list, entries) {
if (userlist_matches(parse_tree, pw, &us->users) != ALLOW)
continue;
TAILQ_FOREACH_REVERSE(priv, &us->privileges, privilege_list, entries) {
host_match = hostlist_matches(parse_tree, pw, &priv->hostlist);
if (host_match != ALLOW)
continue;
TAILQ_FOREACH_REVERSE(cs, &priv->cmndlist, cmndspec_list, entries) {
if (cs->notbefore != UNSPEC) {
if (now < cs->notbefore)
continue;
}
if (cs->notafter != UNSPEC) {
if (now > cs->notafter)
continue;
}
runas_match = runaslist_matches(parse_tree, cs->runasuserlist,
cs->runasgrouplist, NULL, NULL);
if (runas_match == ALLOW) {
cmnd_match = cmnd_matches(parse_tree, cs->cmnd,
cs->runchroot, NULL);
if (cmnd_match != UNSPEC) {
match_info->parse_tree = parse_tree;
match_info->us = us;
match_info->priv = priv;
match_info->cs = cs;
goto done;
}
}
}
}
}
done:
ctx->user.cmnd = saved_user_cmnd;
ctx->user.cmnd_base = saved_user_base;
debug_return_int(cmnd_match);
}
/*
* Check ctx->user.cmnd against sudoers and print the matching entry if the
* command is allowed.
* Returns true if the command is allowed, false if not or -1 on error.
*/
int
display_cmnd(struct sudoers_context *ctx, const struct sudo_nss_list *snl,
struct passwd *pw, int verbose)
{
struct sudoers_match_info match_info = { NULL };
struct sudo_lbuf lbuf;
struct sudo_nss *nss;
int m, match = UNSPEC;
int ret = false;
time_t now;
debug_decl(display_cmnd, SUDOERS_DEBUG_PARSER);
/* Iterate over each source, checking for the command. */
time(&now);
sudo_lbuf_init(&lbuf, output, 0, NULL, 0);
TAILQ_FOREACH(nss, snl, entries) {
if (nss->query(ctx, nss, pw) == -1) {
/* The query function should have printed an error message. */
debug_return_int(-1);
}
m = display_cmnd_check(ctx, nss->parse_tree, pw, now, &match_info);
if (m != UNSPEC)
match = m;
if (!sudo_nss_can_continue(nss, m))
break;
}
if (match == ALLOW) {
if (verbose < 0) {
/* Nothing to display. */
debug_return_int(true);
}
if (verbose) {
/* Append matching sudoers rule (long form). */
display_cmndspec_long(match_info.parse_tree, pw, match_info.us,
match_info.priv, match_info.cs, NULL, &lbuf);
sudo_lbuf_append(&lbuf, " Matched: ");
}
sudo_lbuf_append(&lbuf, "%s%s%s\n", ctx->user.cmnd_list,
ctx->user.cmnd_args ? " " : "",
ctx->user.cmnd_args ? ctx->user.cmnd_args : "");
sudo_lbuf_print(&lbuf);
ret = sudo_lbuf_error(&lbuf) ? -1 : true;
sudo_lbuf_destroy(&lbuf);
}
debug_return_int(ret);
}