/*
* verify that a path generated by mkdtemp() or mkstemp() looks like a
* reasonable expansion of the template and matches the fd. Returns true
* if all the X's were replaced with non-X's
*/
int
check(int fd, char const *kind, char const *path, char const *prefix,
size_t plen, char const *suffix, size_t slen, int tlen)
{
struct stat sb, fsb;
char const *p;
if (tlen < MIN_Xs) {
if (fd != -1)
sudo_fatalx("%s(%s) succeed with too few Xs", kind, path);
if (errno != EINVAL)
sudo_fatal("%s(%s) failed with wrong errno: %d", kind, path, errno);
return 1;
}
if (fd == -1)
sudo_fatal("%s(%s)", kind, path);
if (stat(path, &sb))
sudo_fatal("%s: stat(%s)", kind, path);
if (fd >= 0) {
if (fstat(fd, &fsb))
sudo_fatal("%s: fstat(%d==%s)", kind, fd, path);
if (sb.st_dev != fsb.st_dev || sb.st_ino != fsb.st_ino)
sudo_fatalx("%s: stat mismatch", kind);
}
if (memcmp(path, prefix, plen) != 0)
sudo_fatalx("%s: prefix changed! %s vs %s", kind, prefix, path);
if (memcmp(path + plen + tlen, suffix, slen + 1) != 0)
sudo_fatalx("%s: suffix changed! %s vs %s", kind, suffix, path);
for (p = path + plen; p < path + plen + tlen; p++)
if (*p == '\0')
sudo_fatalx("%s: unexpected truncation", kind);
else if (*p == 'X')
return 0;
return 1;
}
static int
audit_role_change(const security_context_t old_context,
const security_context_t new_context, const char *ttyn, int result)
{
int au_fd, rc = -1;
char *message;
debug_decl(audit_role_change, SUDO_DEBUG_SELINUX)
au_fd = audit_open();
if (au_fd == -1) {
/* Kernel may not have audit support. */
if (errno != EINVAL && errno != EPROTONOSUPPORT && errno != EAFNOSUPPORT
)
sudo_fatal(U_("unable to open audit system"));
} else {
/* audit role change using the same format as newrole(1) */
rc = asprintf(&message, "newrole: old-context=%s new-context=%s",
old_context, new_context);
if (rc == -1)
sudo_fatalx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
rc = audit_log_user_message(au_fd, AUDIT_USER_ROLE_CHANGE,
message, NULL, NULL, ttyn, result);
if (rc <= 0)
sudo_warn(U_("unable to send audit message"));
free(message);
close(au_fd);
}
debug_return_int(rc);
}
void
try_mkdtemp(char *p, char const *prefix, int len)
{
size_t plen = strlen(prefix);
int fd, tries, ok;
for (tries = 0; tries < MAX_TRIES; tries++) {
memcpy(p, prefix, plen);
memset(p + plen, 'X', len);
p[plen + len] = '\0';
fd = mkdtemp(p) ? -2 : -1;
ok = check(fd, "mkdtemp", p, prefix, plen, "", 0, len);
rmdir(p);
if (ok)
return;
}
sudo_fatalx("mkdtemp: exceeded MAX_TRIES");
}
void
try_mkstemps(char *p, char const *prefix, int len, char const *suffix)
{
size_t plen = strlen(prefix);
size_t slen = strlen(suffix);
int tries, fd, ok;
for (tries = 0; tries < MAX_TRIES; tries++) {
memcpy(p, prefix, plen);
memset(p + plen, 'X', len);
memcpy(p + plen + len, suffix, slen + 1);
fd = mkstemps(p, slen);
ok = check(fd, "mkstemp", p, prefix, plen, suffix, slen, len);
close(fd);
unlink(p);
if (ok)
return;
}
sudo_fatalx("mkstemps: exceeded MAX_TRIES");
}
/*
* Exit codes defined in sudo_exec.h:
* SESH_SUCCESS (0) ... successful operation
* SESH_ERR_FAILURE (1) ... unspecified error
* SESH_ERR_INVALID (30) ... invalid -e arg value
* SESH_ERR_BAD_PATHS (31) ... odd number of paths
* SESH_ERR_NO_FILES (32) ... copy error, no files copied
* SESH_ERR_SOME_FILES (33) ... copy error, no files copied
*/
int
main(int argc, char *argv[], char *envp[])
{
int ret;
debug_decl(main, SUDO_DEBUG_MAIN)
initprogname(argc > 0 ? argv[0] : "sesh");
setlocale(LC_ALL, "");
bindtextdomain(PACKAGE_NAME, LOCALEDIR);
textdomain(PACKAGE_NAME);
if (argc < 2)
sudo_fatalx(U_("requires at least one argument"));
/* Read sudo.conf and initialize the debug subsystem. */
if (sudo_conf_read(NULL, SUDO_CONF_DEBUG) == -1)
exit(EXIT_FAILURE);
sudo_debug_register(getprogname(), NULL, NULL,
sudo_conf_debug_files(getprogname()));
if (strcmp(argv[1], "-e") == 0) {
ret = sesh_sudoedit(argc, argv);
} else {
bool login_shell, noexec = false;
char *cp, *cmnd;
int fd = -1;
/* If the first char of argv[0] is '-', we are running a login shell. */
login_shell = argv[0][0] == '-';
/* If argv[0] ends in -noexec, pass the flag to sudo_execve() */
if ((cp = strrchr(argv[0], '-')) != NULL && cp != argv[0])
noexec = strcmp(cp, "-noexec") == 0;
/* If argv[1] is --execfd=%d, extract the fd to exec with. */
if (strncmp(argv[1], "--execfd=", 9) == 0) {
const char *errstr;
cp = argv[1] + 9;
fd = strtonum(cp, 0, INT_MAX, &errstr);
if (errstr != NULL)
sudo_fatalx(U_("invalid file descriptor number: %s"), cp);
argv++;
argc--;
}
/* Shift argv and make a copy of the command to execute. */
argv++;
argc--;
if ((cmnd = strdup(argv[0])) == NULL)
sudo_fatalx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
/* If invoked as a login shell, modify argv[0] accordingly. */
if (login_shell) {
if ((cp = strrchr(argv[0], '/')) == NULL)
sudo_fatal(U_("unable to run %s as a login shell"), argv[0]);
*cp = '-';
argv[0] = cp;
}
sudo_execve(fd, cmnd, argv, envp, noexec);
sudo_warn(U_("unable to execute %s"), cmnd);
ret = SESH_ERR_FAILURE;
}
sudo_debug_exit_int(__func__, __FILE__, __LINE__, sudo_debug_subsys, ret);
_exit(ret);
}
struct log_info *
parse_logfile(const char *logfile)
{
FILE *fp;
char *buf = NULL, *cp, *ep;
const char *errstr;
size_t bufsize = 0, cwdsize = 0, cmdsize = 0;
struct log_info *li = NULL;
debug_decl(parse_logfile, SUDO_DEBUG_UTIL)
fp = fopen(logfile, "r");
if (fp == NULL) {
sudo_warn(U_("unable to open %s"), logfile);
goto bad;
}
/*
* ID file has three lines:
* 1) a log info line
* 2) cwd
* 3) command with args
*/
if ((li = calloc(1, sizeof(*li))) == NULL)
sudo_fatalx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
if (getdelim(&buf, &bufsize, '\n', fp) == -1 ||
getdelim(&li->cwd, &cwdsize, '\n', fp) == -1 ||
getdelim(&li->cmd, &cmdsize, '\n', fp) == -1) {
sudo_warn(U_("%s: invalid log file"), logfile);
goto bad;
}
/* Strip the newline from the cwd and command. */
li->cwd[strcspn(li->cwd, "\n")] = '\0';
li->cmd[strcspn(li->cmd, "\n")] = '\0';
/*
* Crack the log line (rows and cols not present in old versions).
* timestamp:user:runas_user:runas_group:tty:rows:cols
* XXX - probably better to use strtok and switch on the state.
*/
buf[strcspn(buf, "\n")] = '\0';
cp = buf;
/* timestamp */
if ((ep = strchr(cp, ':')) == NULL) {
sudo_warn(U_("%s: time stamp field is missing"), logfile);
goto bad;
}
*ep = '\0';
li->tstamp = strtonum(cp, 0, TIME_T_MAX, &errstr);
if (errstr != NULL) {
sudo_warn(U_("%s: time stamp %s: %s"), logfile, cp, errstr);
goto bad;
}
/* user */
cp = ep + 1;
if ((ep = strchr(cp, ':')) == NULL) {
sudo_warn(U_("%s: user field is missing"), logfile);
goto bad;
}
if ((li->user = strndup(cp, (size_t)(ep - cp))) == NULL)
sudo_fatalx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
/* runas user */
cp = ep + 1;
if ((ep = strchr(cp, ':')) == NULL) {
sudo_warn(U_("%s: runas user field is missing"), logfile);
goto bad;
}
if ((li->runas_user = strndup(cp, (size_t)(ep - cp))) == NULL)
sudo_fatalx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
/* runas group */
cp = ep + 1;
if ((ep = strchr(cp, ':')) == NULL) {
sudo_warn(U_("%s: runas group field is missing"), logfile);
goto bad;
}
if (cp != ep) {
if ((li->runas_group = strndup(cp, (size_t)(ep - cp))) == NULL)
sudo_fatalx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
}
/* tty, followed by optional rows + columns */
cp = ep + 1;
if ((ep = strchr(cp, ':')) == NULL) {
/* just the tty */
if ((li->tty = strdup(cp)) == NULL)
sudo_fatalx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
} else {
/* tty followed by rows + columns */
if ((li->tty = strndup(cp, (size_t)(ep - cp))) == NULL)
sudo_fatalx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
cp = ep + 1;
/* need to NULL out separator to use strtonum() */
if ((ep = strchr(cp, ':')) != NULL) {
*ep = '\0';
}
li->rows = strtonum(cp, 1, INT_MAX, &errstr);
if (errstr != NULL) {
sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO,
"%s: tty rows %s: %s", logfile, cp, errstr);
}
if (ep != NULL) {
cp = ep + 1;
li->cols = strtonum(cp, 1, INT_MAX, &errstr);
if (errstr != NULL) {
sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO,
"%s: tty cols %s: %s", logfile, cp, errstr);
}
}
}
fclose(fp);
free(buf);
debug_return_ptr(li);
bad:
if (fp != NULL)
fclose(fp);
free(buf);
free_log_info(li);
debug_return_ptr(NULL);
}
