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#include "config.h"
#define LIBSSH_STATIC
#include "torture.h"
#include <libssh/libssh.h>
#include "libssh/priv.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <pwd.h>
#include <errno.h>
#include <fcntl.h>
static int sshd_setup(void **state)
{
torture_setup_sshd_server(state, false);
return 0;
}
static int sshd_teardown(void **state) {
torture_teardown_sshd_server(state);
return 0;
}
static int session_setup(void **state)
{
struct torture_state *s = *state;
int verbosity = torture_libssh_verbosity();
struct passwd *pwd;
int rc;
pwd = getpwnam("bob");
assert_non_null(pwd);
rc = setuid(pwd->pw_uid);
assert_return_code(rc, errno);
s->ssh.session = ssh_new();
assert_non_null(s->ssh.session);
ssh_options_set(s->ssh.session, SSH_OPTIONS_LOG_VERBOSITY, &verbosity);
ssh_options_set(s->ssh.session, SSH_OPTIONS_HOST, TORTURE_SSH_SERVER);
ssh_options_set(s->ssh.session, SSH_OPTIONS_USER, TORTURE_SSH_USER_ALICE);
return 0;
}
static int session_teardown(void **state)
{
struct torture_state *s = *state;
ssh_disconnect(s->ssh.session);
ssh_free(s->ssh.session);
return 0;
}
#ifdef NCAT_EXECUTABLE
static void torture_options_set_proxycommand(void **state)
{
struct torture_state *s = *state;
ssh_session session = s->ssh.session;
const char *address = torture_server_address(AF_INET);
int port = torture_server_port();
char command[255] = {0};
struct stat sb;
int rc;
socket_t fd;
rc = stat(NCAT_EXECUTABLE, &sb);
if (rc != 0 || (sb.st_mode & S_IXOTH) == 0) {
SSH_LOG(SSH_LOG_WARNING,
"Could not find " NCAT_EXECUTABLE ": Skipping the test");
skip();
}
rc = snprintf(command,
sizeof(command),
NCAT_EXECUTABLE " %s %d",
address,
port);
assert_true((size_t)rc < sizeof(command));
rc = ssh_options_set(session, SSH_OPTIONS_PROXYCOMMAND, command);
assert_int_equal(rc, 0);
rc = ssh_connect(session);
assert_ssh_return_code(session, rc);
fd = ssh_get_fd(session);
assert_true(fd != SSH_INVALID_SOCKET);
rc = fcntl(fd, F_GETFL);
assert_int_equal(rc & O_RDWR, O_RDWR);
}
#else /* NCAT_EXECUTABLE */
static void torture_options_set_proxycommand(void **state)
{
(void) state;
skip();
}
#endif /* NCAT_EXECUTABLE */
static void torture_options_set_proxycommand_notexist(void **state) {
struct torture_state *s = *state;
ssh_session session = s->ssh.session;
int rc;
rc = ssh_options_set(session, SSH_OPTIONS_PROXYCOMMAND, "this_command_does_not_exist");
assert_ssh_return_code(session, rc);
rc = ssh_connect(session);
assert_ssh_return_code_equal(session, rc, SSH_ERROR);
}
static void torture_options_set_proxycommand_ssh(void **state)
{
struct torture_state *s = *state;
ssh_session session = s->ssh.session;
const char *address = torture_server_address(AF_INET);
char command[255] = {0};
int rc;
socket_t fd;
rc = snprintf(command, sizeof(command),
"ssh -oStrictHostKeyChecking=no -oUserKnownHostsFile=/dev/null -W [%%h]:%%p alice@%s",
address);
assert_true((size_t)rc < sizeof(command));
rc = ssh_options_set(session, SSH_OPTIONS_PROXYCOMMAND, command);
assert_int_equal(rc, 0);
rc = ssh_connect(session);
assert_ssh_return_code(session, rc);
fd = ssh_get_fd(session);
assert_true(fd != SSH_INVALID_SOCKET);
rc = fcntl(fd, F_GETFL);
assert_int_equal(rc & O_RDWR, O_RDWR);
}
static void torture_options_set_proxycommand_ssh_stderr(void **state)
{
struct torture_state *s = *state;
ssh_session session = s->ssh.session;
const char *address = torture_server_address(AF_INET);
char command[255] = {0};
int rc;
socket_t fd;
/* The -vvv switches produce the desired output on the standard error */
rc = snprintf(command, sizeof(command),
"ssh -vvv -oStrictHostKeyChecking=no -oUserKnownHostsFile=/dev/null -W [%%h]:%%p alice@%s",
address);
assert_true((size_t)rc < sizeof(command));
rc = ssh_options_set(session, SSH_OPTIONS_PROXYCOMMAND, command);
assert_int_equal(rc, 0);
rc = ssh_connect(session);
assert_ssh_return_code(session, rc);
fd = ssh_get_fd(session);
assert_true(fd != SSH_INVALID_SOCKET);
rc = fcntl(fd, F_GETFL);
assert_int_equal(rc & O_RDWR, O_RDWR);
}
static void torture_options_proxycommand_injection(void **state)
{
struct torture_state *s = *state;
struct passwd *pwd = NULL;
const char *malicious_host = "`echo foo > mfile`";
const char *command = "nc %h %p";
char *current_dir = NULL;
char *malicious_file_path = NULL;
int mfp_len;
int verbosity = torture_libssh_verbosity();
struct stat sb;
int rc;
pwd = getpwnam("bob");
assert_non_null(pwd);
rc = setuid(pwd->pw_uid);
assert_return_code(rc, errno);
s->ssh.session = ssh_new();
assert_non_null(s->ssh.session);
ssh_options_set(s->ssh.session, SSH_OPTIONS_LOG_VERBOSITY, &verbosity);
// if we would be checking the rc, this should fail
ssh_options_set(s->ssh.session, SSH_OPTIONS_HOST, malicious_host);
ssh_options_set(s->ssh.session, SSH_OPTIONS_USER, TORTURE_SSH_USER_ALICE);
rc = ssh_options_set(s->ssh.session, SSH_OPTIONS_PROXYCOMMAND, command);
assert_int_equal(rc, 0);
rc = ssh_connect(s->ssh.session);
assert_ssh_return_code_equal(s->ssh.session, rc, SSH_ERROR);
current_dir = torture_get_current_working_dir();
assert_non_null(current_dir);
mfp_len = strlen(current_dir) + 6;
malicious_file_path = malloc(mfp_len);
assert_non_null(malicious_file_path);
rc = snprintf(malicious_file_path, mfp_len,
"%s/mfile", current_dir);
assert_int_equal(rc, mfp_len);
free(current_dir);
rc = stat(malicious_file_path, &sb);
assert_int_not_equal(rc, 0);
// cleanup
remove(malicious_file_path);
free(malicious_file_path);
}
int torture_run_tests(void) {
int rc;
struct CMUnitTest tests[] = {
cmocka_unit_test_setup_teardown(torture_options_set_proxycommand,
session_setup,
session_teardown),
cmocka_unit_test_setup_teardown(torture_options_set_proxycommand_notexist,
session_setup,
session_teardown),
cmocka_unit_test_setup_teardown(torture_options_set_proxycommand_ssh,
session_setup,
session_teardown),
cmocka_unit_test_setup_teardown(torture_options_set_proxycommand_ssh_stderr,
session_setup,
session_teardown),
cmocka_unit_test_setup_teardown(torture_options_proxycommand_injection,
NULL,
session_teardown),
};
ssh_init();
torture_filter_tests(tests);
rc = cmocka_run_group_tests(tests, sshd_setup, sshd_teardown);
ssh_finalize();
return rc;
}
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