2 * Copyright (c) 2010-2011 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>
20 #include <sys/param.h>
32 #endif /* STDC_HEADERS */
34 # if defined(HAVE_MEMORY_H) && !defined(STDC_HEADERS)
38 #endif /* HAVE_STRING_H */
41 #endif /* HAVE_STRINGS_H */
44 #endif /* HAVE_UNISTD_H */
52 #include <pathnames.h>
53 #include "sudo_plugin.h"
57 * Sample plugin module that allows any user who knows the password
58 * ("test") to run any command as root. Since there is no credential
59 * caching the validate and invalidate functions are NULL.
63 # define ROOT_UID 65535
75 static struct plugin_state {
77 char * const *settings;
78 char * const *user_info;
80 static sudo_conv_t sudo_conv;
81 static sudo_printf_t sudo_log;
82 static FILE *input, *output;
83 static uid_t runas_uid = ROOT_UID;
84 static gid_t runas_gid = -1;
85 static int use_sudoedit = FALSE;
88 * Allocate storage for a name=value string and return it.
91 fmt_string(const char *var, const char *val)
93 size_t var_len = strlen(var);
94 size_t val_len = strlen(val);
97 cp = str = malloc(var_len + 1 + val_len + 1);
99 memcpy(cp, var, var_len);
102 memcpy(cp, val, val_len);
111 * Plugin policy open function.
114 policy_open(unsigned int version, sudo_conv_t conversation,
115 sudo_printf_t sudo_printf, char * const settings[],
116 char * const user_info[], char * const user_env[])
120 const char *runas_user = NULL;
122 const char *runas_group = NULL;
125 sudo_conv = conversation;
127 sudo_log = sudo_printf;
129 if (SUDO_API_VERSION_GET_MAJOR(version) != SUDO_API_VERSION_MAJOR) {
130 sudo_log(SUDO_CONV_ERROR_MSG,
131 "the sample plugin requires API version %d.x\n",
132 SUDO_API_VERSION_MAJOR);
136 /* Only allow commands to be run as root. */
137 for (ui = settings; *ui != NULL; ui++) {
138 if (strncmp(*ui, "runas_user=", sizeof("runas_user=") - 1) == 0) {
139 runas_user = *ui + sizeof("runas_user=") - 1;
141 if (strncmp(*ui, "runas_group=", sizeof("runas_group=") - 1) == 0) {
142 runas_group = *ui + sizeof("runas_group=") - 1;
144 #if !defined(HAVE_GETPROGNAME) && !defined(HAVE___PROGNAME)
145 if (strncmp(*ui, "progname=", sizeof("progname=") - 1) == 0) {
146 setprogname(*ui + sizeof("progname=") - 1);
149 /* Check to see if sudo was called as sudoedit or with -e flag. */
150 if (strncmp(*ui, "sudoedit=", sizeof("sudoedit=") - 1) == 0) {
151 if (strcasecmp(*ui + sizeof("sudoedit=") - 1, "true") == 0)
154 /* This plugin doesn't support running sudo with no arguments. */
155 if (strncmp(*ui, "implied_shell=", sizeof("implied_shell=") - 1) == 0) {
156 if (strcasecmp(*ui + sizeof("implied_shell=") - 1, "true") == 0)
157 return -2; /* usage error */
160 if (runas_user != NULL) {
161 if ((pw = getpwnam(runas_user)) == NULL) {
162 sudo_log(SUDO_CONV_ERROR_MSG, "unknown user %s\n", runas_user);
165 runas_uid = pw->pw_uid;
167 if (runas_group != NULL) {
168 if ((gr = getgrnam(runas_group)) == NULL) {
169 sudo_log(SUDO_CONV_ERROR_MSG, "unknown group %s\n", runas_group);
172 runas_gid = gr->gr_gid;
176 plugin_state.envp = (char **)user_env;
177 plugin_state.settings = settings;
178 plugin_state.user_info = user_info;
184 find_in_path(char *command, char **envp)
187 char *path, *path0, **ep, *cp;
188 char pathbuf[PATH_MAX], *qualified = NULL;
190 if (strchr(command, '/') != NULL)
193 path = _PATH_DEFPATH;
194 for (ep = plugin_state.envp; *ep != NULL; ep++) {
195 if (strncmp(*ep, "PATH=", 5) == 0) {
200 path = path0 = strdup(path);
202 if ((cp = strchr(path, ':')))
204 snprintf(pathbuf, sizeof(pathbuf), "%s/%s", *path ? path : ".",
206 if (stat(pathbuf, &sb) == 0) {
207 if (S_ISREG(sb.st_mode) && (sb.st_mode & 0000111)) {
213 } while (cp != NULL);
215 return qualified ? strdup(qualified) : NULL;
221 struct sudo_conv_message msg;
222 struct sudo_conv_reply repl;
224 /* Prompt user for password via conversation function. */
225 memset(&msg, 0, sizeof(msg));
226 msg.msg_type = SUDO_CONV_PROMPT_ECHO_OFF;
227 msg.msg = "Password: ";
228 memset(&repl, 0, sizeof(repl));
229 sudo_conv(1, &msg, &repl);
230 if (repl.reply == NULL) {
231 sudo_log(SUDO_CONV_ERROR_MSG, "missing password\n");
234 if (strcmp(repl.reply, "test") != 0) {
235 sudo_log(SUDO_CONV_ERROR_MSG, "incorrect password\n");
242 build_command_info(char *command)
244 static char **command_info;
247 /* Setup command info. */
248 command_info = calloc(32, sizeof(char *));
249 if (command_info == NULL)
251 if ((command_info[i++] = fmt_string("command", command)) == NULL ||
252 asprintf(&command_info[i++], "runas_euid=%ld", (long)runas_uid) == -1 ||
253 asprintf(&command_info[i++], "runas_uid=%ld", (long)runas_uid) == -1) {
256 if (runas_gid != -1) {
257 if (asprintf(&command_info[i++], "runas_gid=%ld", (long)runas_gid) == -1 ||
258 asprintf(&command_info[i++], "runas_egid=%ld", (long)runas_gid) == -1) {
263 command_info[i] = strdup("sudoedit=true");
264 if (command_info[i++] == NULL)
268 command_info[i++] = "timeout=30";
274 find_editor(int nfiles, char * const files[], char **argv_out[])
276 char *cp, **ep, **nargv, *editor, *editor_path;
277 int ac, i, nargc, wasblank;
279 /* Lookup EDITOR in user's environment. */
281 for (ep = plugin_state.envp; *ep != NULL; ep++) {
282 if (strncmp(*ep, "EDITOR=", 7) == 0) {
287 editor = strdup(editor);
288 if (editor == NULL) {
289 sudo_log(SUDO_CONV_ERROR_MSG, "unable to allocate memory\n");
294 * Split editor into an argument vector; editor is reused (do not free).
295 * The EDITOR environment variables may contain command
296 * line args so look for those and alloc space for them too.
299 for (wasblank = 0, cp = editor; *cp != '\0'; cp++) {
300 if (isblank((unsigned char) *cp))
307 /* If we can't find the editor in the user's PATH, give up. */
308 cp = strtok(editor, " \t");
310 (editor_path = find_in_path(editor, plugin_state.envp)) == NULL) {
313 nargv = (char **) malloc((nargc + 1 + nfiles + 1) * sizeof(char *));
315 sudo_log(SUDO_CONV_ERROR_MSG, "unable to allocate memory\n");
318 for (ac = 0; cp != NULL && ac < nargc; ac++) {
320 cp = strtok(NULL, " \t");
323 for (i = 0; i < nfiles; )
324 nargv[ac++] = files[i++];
332 * Plugin policy check function.
333 * Simple example that prompts for a password, hard-coded to "test".
336 policy_check(int argc, char * const argv[],
337 char *env_add[], char **command_info_out[],
338 char **argv_out[], char **user_env_out[])
342 if (!argc || argv[0] == NULL) {
343 sudo_log(SUDO_CONV_ERROR_MSG, "no command specified\n");
350 command = find_in_path(argv[0], plugin_state.envp);
351 if (command == NULL) {
352 sudo_log(SUDO_CONV_ERROR_MSG, "%s: command not found\n", argv[0]);
356 /* If "sudo vi" is run, auto-convert to sudoedit. */
357 if (strcmp(command, _PATH_VI) == 0)
361 /* Rebuild argv using editor */
362 command = find_editor(argc - 1, argv + 1, argv_out);
363 if (command == NULL) {
364 sudo_log(SUDO_CONV_ERROR_MSG, "unable to find valid editor\n");
369 /* No changes needd to argv */
370 *argv_out = (char **)argv;
373 /* No changes to envp */
374 *user_env_out = plugin_state.envp;
376 /* Setup command info. */
377 *command_info_out = build_command_info(command);
378 if (*command_info_out == NULL) {
379 sudo_log(SUDO_CONV_ERROR_MSG, "out of memory\n");
387 policy_list(int argc, char * const argv[], int verbose, const char *list_user)
390 * List user's capabilities.
392 sudo_log(SUDO_CONV_INFO_MSG, "Validated users may run any command\n");
397 policy_version(int verbose)
399 sudo_log(SUDO_CONV_INFO_MSG, "Sample policy plugin version %s\n", PACKAGE_VERSION);
404 policy_close(int exit_status, int error)
407 * The policy might log the command exit status here.
408 * In this example, we just print a message.
411 sudo_log(SUDO_CONV_ERROR_MSG, "Command error: %s\n", strerror(error));
413 if (WIFEXITED(exit_status)) {
414 sudo_log(SUDO_CONV_INFO_MSG, "Command exited with status %d\n",
415 WEXITSTATUS(exit_status));
416 } else if (WIFSIGNALED(exit_status)) {
417 sudo_log(SUDO_CONV_INFO_MSG, "Command killed by signal %d\n",
418 WTERMSIG(exit_status));
424 io_open(unsigned int version, sudo_conv_t conversation,
425 sudo_printf_t sudo_printf, char * const settings[],
426 char * const user_info[], char * const command_info[],
427 int argc, char * const argv[], char * const user_env[])
433 sudo_conv = conversation;
435 sudo_log = sudo_printf;
437 /* Open input and output files. */
438 snprintf(path, sizeof(path), "/var/tmp/sample-%u.output",
439 (unsigned int)getpid());
440 fd = open(path, O_WRONLY|O_CREAT|O_EXCL, 0644);
443 output = fdopen(fd, "w");
445 snprintf(path, sizeof(path), "/var/tmp/sample-%u.input",
446 (unsigned int)getpid());
447 fd = open(path, O_WRONLY|O_CREAT|O_EXCL, 0644);
450 input = fdopen(fd, "w");
456 io_close(int exit_status, int error)
463 io_version(int verbose)
465 sudo_log(SUDO_CONV_INFO_MSG, "Sample I/O plugin version %s\n",
471 io_log_input(const char *buf, unsigned int len)
473 fwrite(buf, len, 1, input);
478 io_log_output(const char *buf, unsigned int len)
480 fwrite(buf, len, 1, output);
484 struct policy_plugin sample_policy = {
493 NULL /* invalidate */
497 * Note: This plugin does not differentiate between tty and pipe I/O.
498 * It all gets logged to the same file.
500 struct io_plugin sample_io = {
506 io_log_input, /* tty input */
507 io_log_output, /* tty output */
508 io_log_input, /* command stdin if not tty */
509 io_log_output, /* command stdout if not tty */
510 io_log_output /* command stderr if not tty */