2 * Copyright (c) 2010-2013 Todd C. Miller <Todd.Miller@courtesan.com>
4 * Permission to use, copy, modify, and distribute this software for any
5 * purpose with or without fee is hereby granted, provided that the above
6 * copyright notice and this permission notice appear in all copies.
8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
19 #include <sys/types.h>
31 #endif /* STDC_HEADERS */
35 # include "compat/stdbool.h"
36 #endif /* HAVE_STDBOOL_H */
38 # if defined(HAVE_MEMORY_H) && !defined(STDC_HEADERS)
42 #endif /* HAVE_STRING_H */
45 #endif /* HAVE_STRINGS_H */
48 #endif /* HAVE_UNISTD_H */
56 #include <pathnames.h>
57 #include "sudo_plugin.h"
61 * Sample plugin module that allows any user who knows the password
62 * ("test") to run any command as root. Since there is no credential
63 * caching the validate and invalidate functions are NULL.
67 # define ROOT_UID 65535
72 static struct plugin_state {
74 char * const *settings;
75 char * const *user_info;
77 static sudo_conv_t sudo_conv;
78 static sudo_printf_t sudo_log;
79 static FILE *input, *output;
80 static uid_t runas_uid = ROOT_UID;
81 static gid_t runas_gid = -1;
82 static int use_sudoedit = false;
85 * Allocate storage for a name=value string and return it.
88 fmt_string(const char *var, const char *val)
90 size_t var_len = strlen(var);
91 size_t val_len = strlen(val);
94 cp = str = malloc(var_len + 1 + val_len + 1);
96 memcpy(cp, var, var_len);
99 memcpy(cp, val, val_len);
108 * Plugin policy open function.
111 policy_open(unsigned int version, sudo_conv_t conversation,
112 sudo_printf_t sudo_printf, char * const settings[],
113 char * const user_info[], char * const user_env[], char * const args[])
117 const char *runas_user = NULL;
119 const char *runas_group = NULL;
122 sudo_conv = conversation;
124 sudo_log = sudo_printf;
126 if (SUDO_API_VERSION_GET_MAJOR(version) != SUDO_API_VERSION_MAJOR) {
127 sudo_log(SUDO_CONV_ERROR_MSG,
128 "the sample plugin requires API version %d.x\n",
129 SUDO_API_VERSION_MAJOR);
133 /* Only allow commands to be run as root. */
134 for (ui = settings; *ui != NULL; ui++) {
135 if (strncmp(*ui, "runas_user=", sizeof("runas_user=") - 1) == 0) {
136 runas_user = *ui + sizeof("runas_user=") - 1;
138 if (strncmp(*ui, "runas_group=", sizeof("runas_group=") - 1) == 0) {
139 runas_group = *ui + sizeof("runas_group=") - 1;
141 #if !defined(HAVE_GETPROGNAME) && !defined(HAVE___PROGNAME)
142 if (strncmp(*ui, "progname=", sizeof("progname=") - 1) == 0) {
143 setprogname(*ui + sizeof("progname=") - 1);
146 /* Check to see if sudo was called as sudoedit or with -e flag. */
147 if (strncmp(*ui, "sudoedit=", sizeof("sudoedit=") - 1) == 0) {
148 if (strcasecmp(*ui + sizeof("sudoedit=") - 1, "true") == 0)
151 /* This plugin doesn't support running sudo with no arguments. */
152 if (strncmp(*ui, "implied_shell=", sizeof("implied_shell=") - 1) == 0) {
153 if (strcasecmp(*ui + sizeof("implied_shell=") - 1, "true") == 0)
154 return -2; /* usage error */
157 if (runas_user != NULL) {
158 if ((pw = getpwnam(runas_user)) == NULL) {
159 sudo_log(SUDO_CONV_ERROR_MSG, "unknown user %s\n", runas_user);
162 runas_uid = pw->pw_uid;
164 if (runas_group != NULL) {
165 if ((gr = getgrnam(runas_group)) == NULL) {
166 sudo_log(SUDO_CONV_ERROR_MSG, "unknown group %s\n", runas_group);
169 runas_gid = gr->gr_gid;
173 plugin_state.envp = (char **)user_env;
174 plugin_state.settings = settings;
175 plugin_state.user_info = user_info;
181 find_in_path(char *command, char **envp)
184 char *path, *path0, **ep, *cp;
185 char pathbuf[PATH_MAX], *qualified = NULL;
187 if (strchr(command, '/') != NULL)
190 path = _PATH_DEFPATH;
191 for (ep = plugin_state.envp; *ep != NULL; ep++) {
192 if (strncmp(*ep, "PATH=", 5) == 0) {
197 path = path0 = strdup(path);
199 if ((cp = strchr(path, ':')))
201 snprintf(pathbuf, sizeof(pathbuf), "%s/%s", *path ? path : ".",
203 if (stat(pathbuf, &sb) == 0) {
204 if (S_ISREG(sb.st_mode) && (sb.st_mode & 0000111)) {
210 } while (cp != NULL);
212 return qualified ? strdup(qualified) : NULL;
218 struct sudo_conv_message msg;
219 struct sudo_conv_reply repl;
221 /* Prompt user for password via conversation function. */
222 memset(&msg, 0, sizeof(msg));
223 msg.msg_type = SUDO_CONV_PROMPT_ECHO_OFF;
224 msg.msg = "Password: ";
225 memset(&repl, 0, sizeof(repl));
226 sudo_conv(1, &msg, &repl);
227 if (repl.reply == NULL) {
228 sudo_log(SUDO_CONV_ERROR_MSG, "missing password\n");
231 if (strcmp(repl.reply, "test") != 0) {
232 sudo_log(SUDO_CONV_ERROR_MSG, "incorrect password\n");
239 build_command_info(const char *command)
241 static char **command_info;
244 /* Setup command info. */
245 command_info = calloc(32, sizeof(char *));
246 if (command_info == NULL)
248 if ((command_info[i++] = fmt_string("command", command)) == NULL ||
249 asprintf(&command_info[i++], "runas_euid=%ld", (long)runas_uid) == -1 ||
250 asprintf(&command_info[i++], "runas_uid=%ld", (long)runas_uid) == -1) {
253 if (runas_gid != -1) {
254 if (asprintf(&command_info[i++], "runas_gid=%ld", (long)runas_gid) == -1 ||
255 asprintf(&command_info[i++], "runas_egid=%ld", (long)runas_gid) == -1) {
260 command_info[i] = strdup("sudoedit=true");
261 if (command_info[i++] == NULL)
265 command_info[i++] = "timeout=30";
271 find_editor(int nfiles, char * const files[], char **argv_out[])
273 char *cp, **ep, **nargv, *editor, *editor_path;
274 int ac, i, nargc, wasblank;
276 /* Lookup EDITOR in user's environment. */
278 for (ep = plugin_state.envp; *ep != NULL; ep++) {
279 if (strncmp(*ep, "EDITOR=", 7) == 0) {
284 editor = strdup(editor);
285 if (editor == NULL) {
286 sudo_log(SUDO_CONV_ERROR_MSG, "unable to allocate memory\n");
291 * Split editor into an argument vector; editor is reused (do not free).
292 * The EDITOR environment variables may contain command
293 * line args so look for those and alloc space for them too.
296 for (wasblank = 0, cp = editor; *cp != '\0'; cp++) {
297 if (isblank((unsigned char) *cp))
304 /* If we can't find the editor in the user's PATH, give up. */
305 cp = strtok(editor, " \t");
307 (editor_path = find_in_path(editor, plugin_state.envp)) == NULL) {
311 if (editor_path != editor)
313 nargv = (char **) malloc((nargc + 1 + nfiles + 1) * sizeof(char *));
315 sudo_log(SUDO_CONV_ERROR_MSG, "unable to allocate memory\n");
319 for (ac = 0; cp != NULL && ac < nargc; ac++) {
321 cp = strtok(NULL, " \t");
324 for (i = 0; i < nfiles; )
325 nargv[ac++] = files[i++];
333 * Plugin policy check function.
334 * Simple example that prompts for a password, hard-coded to "test".
337 policy_check(int argc, char * const argv[],
338 char *env_add[], char **command_info_out[],
339 char **argv_out[], char **user_env_out[])
343 if (!argc || argv[0] == NULL) {
344 sudo_log(SUDO_CONV_ERROR_MSG, "no command specified\n");
351 command = find_in_path(argv[0], plugin_state.envp);
352 if (command == NULL) {
353 sudo_log(SUDO_CONV_ERROR_MSG, "%s: command not found\n", argv[0]);
357 /* If "sudo vi" is run, auto-convert to sudoedit. */
358 if (strcmp(command, _PATH_VI) == 0)
362 /* Rebuild argv using editor */
364 command = find_editor(argc - 1, argv + 1, argv_out);
365 if (command == NULL) {
366 sudo_log(SUDO_CONV_ERROR_MSG, "unable to find valid editor\n");
371 /* No changes needd to argv */
372 *argv_out = (char **)argv;
375 /* No changes to envp */
376 *user_env_out = plugin_state.envp;
378 /* Setup command info. */
379 *command_info_out = build_command_info(command);
381 if (*command_info_out == NULL) {
382 sudo_log(SUDO_CONV_ERROR_MSG, "out of memory\n");
390 policy_list(int argc, char * const argv[], int verbose, const char *list_user)
393 * List user's capabilities.
395 sudo_log(SUDO_CONV_INFO_MSG, "Validated users may run any command\n");
400 policy_version(int verbose)
402 sudo_log(SUDO_CONV_INFO_MSG, "Sample policy plugin version %s\n", PACKAGE_VERSION);
407 policy_close(int exit_status, int error)
410 * The policy might log the command exit status here.
411 * In this example, we just print a message.
414 sudo_log(SUDO_CONV_ERROR_MSG, "Command error: %s\n", strerror(error));
416 if (WIFEXITED(exit_status)) {
417 sudo_log(SUDO_CONV_INFO_MSG, "Command exited with status %d\n",
418 WEXITSTATUS(exit_status));
419 } else if (WIFSIGNALED(exit_status)) {
420 sudo_log(SUDO_CONV_INFO_MSG, "Command killed by signal %d\n",
421 WTERMSIG(exit_status));
427 io_open(unsigned int version, sudo_conv_t conversation,
428 sudo_printf_t sudo_printf, char * const settings[],
429 char * const user_info[], char * const command_info[],
430 int argc, char * const argv[], char * const user_env[], char * const args[])
436 sudo_conv = conversation;
438 sudo_log = sudo_printf;
440 /* Open input and output files. */
441 snprintf(path, sizeof(path), "/var/tmp/sample-%u.output",
442 (unsigned int)getpid());
443 fd = open(path, O_WRONLY|O_CREAT|O_EXCL, 0644);
446 output = fdopen(fd, "w");
448 snprintf(path, sizeof(path), "/var/tmp/sample-%u.input",
449 (unsigned int)getpid());
450 fd = open(path, O_WRONLY|O_CREAT|O_EXCL, 0644);
453 input = fdopen(fd, "w");
459 io_close(int exit_status, int error)
466 io_version(int verbose)
468 sudo_log(SUDO_CONV_INFO_MSG, "Sample I/O plugin version %s\n",
474 io_log_input(const char *buf, unsigned int len)
476 ignore_result(fwrite(buf, len, 1, input));
481 io_log_output(const char *buf, unsigned int len)
483 ignore_result(fwrite(buf, len, 1, output));
487 struct policy_plugin sample_policy = {
496 NULL, /* invalidate */
497 NULL, /* init_session */
498 NULL, /* register_hooks */
499 NULL /* deregister_hooks */
503 * Note: This plugin does not differentiate between tty and pipe I/O.
504 * It all gets logged to the same file.
506 __dso_public struct io_plugin sample_io = {
512 io_log_input, /* tty input */
513 io_log_output, /* tty output */
514 io_log_input, /* command stdin if not tty */
515 io_log_output, /* command stdout if not tty */
516 io_log_output /* command stderr if not tty */