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Fix SSH2 resource ownership and stream error handling #103

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Fix SSH2 resource ownership and stream error handling #103

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5 changes: 5 additions & 0 deletions php_ssh2.h
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Original file line number Diff line number Diff line change
Expand Up @@ -170,6 +170,11 @@ extern php_stream_wrapper php_ssh2_sftp_wrapper;
extern int le_ssh2_session;
extern int le_ssh2_sftp;

static inline zend_bool php_ssh2_session_is_open(zend_resource *session_rsrc)
{
return session_rsrc && session_rsrc->ptr != NULL;
}

#if PHP_VERSION_ID < 70300
#define SSH2_URL_STR(a) (a)
#define SSH2_URL_LEN(a) strlen(a)
Expand Down
47 changes: 43 additions & 4 deletions ssh2.c
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Original file line number Diff line number Diff line change
Expand Up @@ -906,6 +906,10 @@ PHP_FUNCTION(ssh2_forward_accept)
RETURN_FALSE;
}

if (!php_ssh2_session_is_open(data->session_rsrc)) {
RETURN_FALSE;
}

channel = libssh2_channel_forward_accept(data->listener);

if (!channel) {
Expand All @@ -916,6 +920,7 @@ PHP_FUNCTION(ssh2_forward_accept)
channel_data->channel = channel;
channel_data->streamid = 0;
channel_data->is_blocking = 0;
channel_data->timeout = 0;
channel_data->session_rsrc = data->session_rsrc;
channel_data->refcount = NULL;

Expand Down Expand Up @@ -1010,12 +1015,28 @@ PHP_FUNCTION(ssh2_poll)
res_type = Z_RES_P(tmpzval)->type;
res = zend_fetch_resource_ex(tmpzval, "Poll Resource", res_type);
if (res_type == le_ssh2_listener) {
php_ssh2_listener_data *listener_data = (php_ssh2_listener_data*)res;

if (!php_ssh2_session_is_open(listener_data->session_rsrc)) {
php_error_docref(NULL, E_WARNING, "Cannot poll a listener after its session is closed");
numfds--;
continue;
}

pollfds[i].type = LIBSSH2_POLLFD_LISTENER;
pollfds[i].fd.listener = ((php_ssh2_listener_data*)res)->listener;
pollfds[i].fd.listener = listener_data->listener;
} else if ((res_type == le_stream || res_type == le_pstream) &&
((php_stream*)res)->ops == &php_ssh2_channel_stream_ops) {
php_ssh2_channel_data *channel_data = (php_ssh2_channel_data*)((php_stream*)res)->abstract;

if (!php_ssh2_session_is_open(channel_data->session_rsrc)) {
php_error_docref(NULL, E_WARNING, "Cannot poll a channel after its session is closed");
numfds--;
continue;
}

pollfds[i].type = LIBSSH2_POLLFD_CHANNEL;
pollfds[i].fd.channel = ((php_ssh2_channel_data*)(((php_stream*)res)->abstract))->channel;
pollfds[i].fd.channel = channel_data->channel;
/* TODO: Add the ability to select against other stream types */
} else {
php_error_docref(NULL, E_WARNING, "Invalid resource type in subarray: %s", zend_rsrc_list_get_rsrc_type(Z_RES_P(tmpzval)));
Expand Down Expand Up @@ -1114,6 +1135,10 @@ PHP_FUNCTION(ssh2_publickey_add)
RETURN_FALSE;
}

if (!php_ssh2_session_is_open(data->session_rsrc)) {
RETURN_FALSE;
}

if (zattrs) {
HashPosition pos;
zval *attr_val;
Expand Down Expand Up @@ -1209,6 +1234,10 @@ PHP_FUNCTION(ssh2_publickey_remove)
RETURN_FALSE;
}

if (!php_ssh2_session_is_open(data->session_rsrc)) {
RETURN_FALSE;
}

if (libssh2_publickey_remove_ex(data->pkey, (unsigned char *) algo, algo_len, (unsigned char *) blob, blob_len)) {
php_error_docref(NULL, E_WARNING, "Unable to remove %s key", algo);
RETURN_FALSE;
Expand Down Expand Up @@ -1236,6 +1265,10 @@ PHP_FUNCTION(ssh2_publickey_list)
RETURN_FALSE;
}

if (!php_ssh2_session_is_open(data->session_rsrc)) {
RETURN_FALSE;
}

if (libssh2_publickey_list_fetch(data->pkey, &num_keys, &keys)) {
php_error_docref(NULL, E_WARNING, "Unable to list keys on remote server");
RETURN_FALSE;
Expand Down Expand Up @@ -1389,7 +1422,10 @@ static void php_ssh2_listener_dtor(zend_resource *rsrc)
php_ssh2_listener_data *data = (php_ssh2_listener_data*)rsrc->ptr;
LIBSSH2_LISTENER *listener = data->listener;

libssh2_channel_forward_cancel(listener);
if (php_ssh2_session_is_open(data->session_rsrc)) {
libssh2_channel_forward_cancel(listener);
}

zend_list_delete(data->session_rsrc);
efree(data);
}
Expand All @@ -1399,7 +1435,10 @@ static void php_ssh2_pkey_subsys_dtor(zend_resource *rsrc)
php_ssh2_pkey_subsys_data *data = (php_ssh2_pkey_subsys_data*)rsrc->ptr;
LIBSSH2_PUBLICKEY *pkey = data->pkey;

libssh2_publickey_shutdown(pkey);
if (php_ssh2_session_is_open(data->session_rsrc)) {
libssh2_publickey_shutdown(pkey);
}

zend_list_delete(data->session_rsrc);
efree(data);
}
Expand Down
118 changes: 81 additions & 37 deletions ssh2_fopen_wrappers.c
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Original file line number Diff line number Diff line change
Expand Up @@ -48,14 +48,20 @@ static ssize_t php_ssh2_channel_stream_write(php_stream *stream, const char *buf
{
php_ssh2_channel_data *abstract = (php_ssh2_channel_data*)stream->abstract;
ssize_t writestate;
LIBSSH2_SESSION *session;

libssh2_channel_set_blocking(abstract->channel, abstract->is_blocking);
session = (LIBSSH2_SESSION *)zend_fetch_resource(abstract->session_rsrc, PHP_SSH2_SESSION_RES_NAME, le_ssh2_session);
#ifdef PHP_SSH2_SESSION_TIMEOUT
LIBSSH2_SESSION *session;
#endif

if (!php_ssh2_session_is_open(abstract->session_rsrc)) {
return -1;
}

libssh2_channel_set_blocking(abstract->channel, abstract->is_blocking);

#ifdef PHP_SSH2_SESSION_TIMEOUT
session = (LIBSSH2_SESSION *)zend_fetch_resource(abstract->session_rsrc, PHP_SSH2_SESSION_RES_NAME, le_ssh2_session);

if (abstract->is_blocking) {
libssh2_session_set_timeout(session, abstract->timeout);
}
Expand All @@ -70,16 +76,8 @@ static ssize_t php_ssh2_channel_stream_write(php_stream *stream, const char *buf
#endif

if (writestate == LIBSSH2_ERROR_EAGAIN) {
#if PHP_VERSION_ID < 70400
writestate = 0;
#endif
} else if (writestate < 0) {
char *error_msg = NULL;
if (libssh2_session_last_error(session, &error_msg, NULL, 0) == writestate) {
php_error_docref(NULL, E_WARNING, "Failure '%s' (%ld)", error_msg, writestate);
}

stream->eof = 1;
#if PHP_VERSION_ID < 70400
writestate = 0;
#endif
Expand All @@ -96,13 +94,21 @@ static ssize_t php_ssh2_channel_stream_read(php_stream *stream, char *buf, size_
{
php_ssh2_channel_data *abstract = (php_ssh2_channel_data*)stream->abstract;
ssize_t readstate;

#ifdef PHP_SSH2_SESSION_TIMEOUT
LIBSSH2_SESSION *session;
#endif

if (!php_ssh2_session_is_open(abstract->session_rsrc)) {
stream->eof = 1;
return -1;
}

stream->eof = libssh2_channel_eof(abstract->channel);
libssh2_channel_set_blocking(abstract->channel, abstract->is_blocking);
session = (LIBSSH2_SESSION *)zend_fetch_resource(abstract->session_rsrc, PHP_SSH2_SESSION_RES_NAME, le_ssh2_session);

#ifdef PHP_SSH2_SESSION_TIMEOUT
session = (LIBSSH2_SESSION *)zend_fetch_resource(abstract->session_rsrc, PHP_SSH2_SESSION_RES_NAME, le_ssh2_session);

if (abstract->is_blocking) {
libssh2_session_set_timeout(session, abstract->timeout);
}
Expand All @@ -117,17 +123,15 @@ static ssize_t php_ssh2_channel_stream_read(php_stream *stream, char *buf, size_
#endif

if (readstate == LIBSSH2_ERROR_EAGAIN) {
#if PHP_VERSION_ID < 70400
stream->eof = 0;
readstate = 0;
#endif
} else if (readstate < 0) {
char *error_msg = NULL;
if (libssh2_session_last_error(session, &error_msg, NULL, 0) == readstate) {
php_error_docref(NULL, E_WARNING, "Failure '%s' (%ld)", error_msg, readstate);
}

stream->eof = 1;
stream->eof = 0;
#if PHP_VERSION_ID < 70400
readstate = 0;
#endif
} else {
stream->eof = (readstate == 0 && libssh2_channel_eof(abstract->channel));
}
return readstate;
}
Expand All @@ -141,8 +145,10 @@ static int php_ssh2_channel_stream_close(php_stream *stream, int close_handle)
if (abstract->refcount) {
efree(abstract->refcount);
}
libssh2_channel_eof(abstract->channel);
libssh2_channel_free(abstract->channel);
if (php_ssh2_session_is_open(abstract->session_rsrc)) {
libssh2_channel_free(abstract->channel);
}

zend_list_delete(abstract->session_rsrc);
}
efree(abstract);
Expand All @@ -154,6 +160,10 @@ static int php_ssh2_channel_stream_flush(php_stream *stream)
{
php_ssh2_channel_data *abstract = (php_ssh2_channel_data*)stream->abstract;

if (!php_ssh2_session_is_open(abstract->session_rsrc)) {
return -1;
}

return libssh2_channel_flush_ex(abstract->channel, abstract->streamid);
}

Expand All @@ -163,6 +173,10 @@ static int php_ssh2_channel_stream_cast(php_stream *stream, int castas, void **r
LIBSSH2_SESSION *session;
php_ssh2_session_data **session_data;

if (!php_ssh2_session_is_open(abstract->session_rsrc)) {
return FAILURE;
}

session = (LIBSSH2_SESSION *)zend_fetch_resource(abstract->session_rsrc, PHP_SSH2_SESSION_RES_NAME, le_ssh2_session);
session_data = (php_ssh2_session_data **)libssh2_session_abstract(session);

Expand Down Expand Up @@ -192,8 +206,10 @@ static int php_ssh2_channel_stream_set_option(php_stream *stream, int option, in
break;

case PHP_STREAM_OPTION_META_DATA_API:
add_assoc_long((zval*)ptrparam, "exit_status", libssh2_channel_get_exit_status(abstract->channel));
break;
if (php_ssh2_session_is_open(abstract->session_rsrc)) {
add_assoc_long((zval*)ptrparam, "exit_status", libssh2_channel_get_exit_status(abstract->channel));
}
return PHP_STREAM_OPTION_RETURN_OK;

case PHP_STREAM_OPTION_READ_TIMEOUT:
ret = abstract->timeout;
Expand All @@ -207,6 +223,10 @@ static int php_ssh2_channel_stream_set_option(php_stream *stream, int option, in
break;

case PHP_STREAM_OPTION_CHECK_LIVENESS:
if (!php_ssh2_session_is_open(abstract->session_rsrc)) {
return stream->eof = 1;
}

return stream->eof = libssh2_channel_eof(abstract->channel);
break;
}
Expand Down Expand Up @@ -303,6 +323,11 @@ php_url *php_ssh2_fopen_wrapper_parse_path(const char *path, char *type, php_str
/* suppress potential warning by passing NULL as resource_type_name */
sftp_data = (php_ssh2_sftp_data *)zend_fetch_resource(Z_RES_P(zresource), NULL, le_ssh2_sftp);
if (sftp_data) {
if (!php_ssh2_session_is_open(sftp_data->session_rsrc)) {
php_url_free(resource);
return NULL;
}

/* Want the sftp layer */
Z_ADDREF_P(zresource);
*psftp_rsrc = Z_RES_P(zresource);
Expand Down Expand Up @@ -347,6 +372,11 @@ php_url *php_ssh2_fopen_wrapper_parse_path(const char *path, char *type, php_str
php_ssh2_sftp_data *sftp_data;
sftp_data = (php_ssh2_sftp_data *)zend_fetch_resource(Z_RES_P(tmpzval), PHP_SSH2_SFTP_RES_NAME, le_ssh2_sftp);
if (sftp_data) {
if (!php_ssh2_session_is_open(sftp_data->session_rsrc)) {
php_url_free(resource);
return NULL;
}

Z_ADDREF_P(tmpzval);
*psftp_rsrc = Z_RES_P(tmpzval);
*psftp = sftp_data->sftp;
Expand Down Expand Up @@ -454,20 +484,23 @@ php_url *php_ssh2_fopen_wrapper_parse_path(const char *path, char *type, php_str
return NULL;
}

if (pubkey_file && privkey_file &&
(php_check_open_basedir(pubkey_file) || php_check_open_basedir(privkey_file))) {
php_url_free(resource);
return NULL;
}

session = php_ssh2_session_connect(SSH2_URL_STR(resource->host), resource->port, methods, callbacks);
if (!session) {
/* Unable to connect! */
php_url_free(resource);
return NULL;
}

ZVAL_RES(&zsession, zend_register_resource(session, le_ssh2_session));

/* Authenticate */
if (pubkey_file && privkey_file) {
if (php_check_open_basedir(pubkey_file) || php_check_open_basedir(privkey_file)) {
php_url_free(resource);
return NULL;
}

/* Attempt pubkey authentication */
if (!libssh2_userauth_publickey_fromfile(session, username, pubkey_file, privkey_file, password)) {
goto session_authed;
Expand All @@ -483,14 +516,10 @@ php_url *php_ssh2_fopen_wrapper_parse_path(const char *path, char *type, php_str

/* Auth failure */
php_url_free(resource);
if (Z_RES(zsession)) {
zend_list_delete(Z_RES(zsession));
}
zend_list_delete(Z_RES(zsession));
return NULL;

session_authed:
ZVAL_RES(&zsession, zend_register_resource(session, le_ssh2_session));

if (psftp && psftp_rsrc) {
LIBSSH2_SFTP *sftp;

Expand All @@ -505,7 +534,6 @@ php_url *php_ssh2_fopen_wrapper_parse_path(const char *path, char *type, php_str
sftp_data->session = session;
sftp_data->sftp = sftp;
sftp_data->session_rsrc = Z_RES(zsession);
Z_ADDREF(zsession);
*psftp_rsrc = zend_register_resource(sftp_data, le_ssh2_sftp);
*psftp = sftp;
}
Expand Down Expand Up @@ -785,6 +813,10 @@ PHP_FUNCTION(ssh2_shell_resize)

data = (php_ssh2_channel_data*)parent->abstract;

if (!php_ssh2_session_is_open(data->session_rsrc)) {
RETURN_FALSE;
}

libssh2_channel_request_pty_size_ex(data->channel, width, height, width_px, height_px);

RETURN_TRUE;
Expand Down Expand Up @@ -1465,6 +1497,10 @@ PHP_FUNCTION(ssh2_fetch_stream)

data = (php_ssh2_channel_data*)parent->abstract;

if (!php_ssh2_session_is_open(data->session_rsrc)) {
RETURN_FALSE;
}

if (!data->refcount) {
data->refcount = emalloc(sizeof(unsigned char));
*(data->refcount) = 1;
Expand All @@ -1485,7 +1521,7 @@ PHP_FUNCTION(ssh2_fetch_stream)
if (!stream) {
php_error_docref(NULL, E_WARNING, "Error opening substream");
efree(stream_data);
(data->refcount)--;
(*(data->refcount))--;
RETURN_FALSE;
}

Expand Down Expand Up @@ -1521,6 +1557,10 @@ PHP_FUNCTION(ssh2_send_signal)
RETURN_FALSE;
}

if (!php_ssh2_session_is_open(data->session_rsrc)) {
RETURN_FALSE;
}

ssh2_ret = libssh2_channel_signal_ex(data->channel, signal->val, signal->len);
if (ssh2_ret < 0) {
php_error_docref(NULL, E_WARNING, "Couldn't send signal %s to channel (Return code %d)", signal->val, ssh2_ret);
Expand Down Expand Up @@ -1558,6 +1598,10 @@ PHP_FUNCTION(ssh2_send_eof)
RETURN_FALSE;
}

if (!php_ssh2_session_is_open(data->session_rsrc)) {
RETURN_FALSE;
}

ssh2_ret = libssh2_channel_send_eof(data->channel);
if (ssh2_ret < 0) {
php_error_docref(NULL, E_WARNING, "Couldn't send EOF to channel (Return code %d)", ssh2_ret);
Expand Down
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