#include "first.h"
#include "base.h"
#include "log.h"
#include "buffer.h"
#include "response.h"
#include "plugin.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <stdlib.h>
#include <string.h>
#ifdef HAVE_PWD_H
# include <pwd.h>
#endif
/* plugin config for all request/connections */
typedef struct {
array *exclude_user;
array *include_user;
buffer *path;
buffer *basepath;
unsigned short letterhomes;
unsigned short active;
} plugin_config;
typedef struct {
PLUGIN_DATA;
buffer *username;
buffer *temp_path;
plugin_config **config_storage;
plugin_config conf;
} plugin_data;
/* init the plugin data */
INIT_FUNC(mod_userdir_init) {
plugin_data *p;
p = calloc(1, sizeof(*p));
p->username = buffer_init();
p->temp_path = buffer_init();
return p;
}
/* detroy the plugin data */
FREE_FUNC(mod_userdir_free) {
plugin_data *p = p_d;
if (!p) return HANDLER_GO_ON;
if (p->config_storage) {
size_t i;
for (i = 0; i < srv->config_context->used; i++) {
plugin_config *s = p->config_storage[i];
if (NULL == s) continue;
array_free(s->include_user);
array_free(s->exclude_user);
buffer_free(s->path);
buffer_free(s->basepath);
free(s);
}
free(p->config_storage);
}
buffer_free(p->username);
buffer_free(p->temp_path);
free(p);
return HANDLER_GO_ON;
}
/* handle plugin config and check values */
SETDEFAULTS_FUNC(mod_userdir_set_defaults) {
plugin_data *p = p_d;
size_t i;
config_values_t cv[] = {
{ "userdir.path", NULL, T_CONFIG_STRING, T_CONFIG_SCOPE_CONNECTION }, /* 0 */
{ "userdir.exclude-user", NULL, T_CONFIG_ARRAY, T_CONFIG_SCOPE_CONNECTION }, /* 1 */
{ "userdir.include-user", NULL, T_CONFIG_ARRAY, T_CONFIG_SCOPE_CONNECTION }, /* 2 */
{ "userdir.basepath", NULL, T_CONFIG_STRING, T_CONFIG_SCOPE_CONNECTION }, /* 3 */
{ "userdir.letterhomes", NULL, T_CONFIG_BOOLEAN,T_CONFIG_SCOPE_CONNECTION }, /* 4 */
{ "userdir.active", NULL, T_CONFIG_BOOLEAN,T_CONFIG_SCOPE_CONNECTION }, /* 5 */
{ NULL, NULL, T_CONFIG_UNSET, T_CONFIG_SCOPE_UNSET }
};
if (!p) return HANDLER_ERROR;
p->config_storage = calloc(1, srv->config_context->used * sizeof(plugin_config *));
for (i = 0; i < srv->config_context->used; i++) {
data_config const* config = (data_config const*)srv->config_context->data[i];
plugin_config *s;
s = calloc(1, sizeof(plugin_config));
s->exclude_user = array_init();
s->include_user = array_init();
s->path = buffer_init();
s->basepath = buffer_init();
s->letterhomes = 0;
/* enabled by default for backward compatibility; if userdir.path isn't set userdir is disabled too,
* but you can't disable it by setting it to an empty string. */
s->active = 1;
cv[0].destination = s->path;
cv[1].destination = s->exclude_user;
cv[2].destination = s->include_user;
cv[3].destination = s->basepath;
cv[4].destination = &(s->letterhomes);
cv[5].destination = &(s->active);
p->config_storage[i] = s;
if (0 != config_insert_values_global(srv, config->value, cv, i == 0 ? T_CONFIG_SCOPE_SERVER : T_CONFIG_SCOPE_CONNECTION)) {
return HANDLER_ERROR;
}
if (!array_is_vlist(s->exclude_user)) {
log_error_write(srv, __FILE__, __LINE__, "s",
"unexpected value for userdir.exclude-user; expected list of \"suffix\"");
return HANDLER_ERROR;
}
if (!array_is_vlist(s->include_user)) {
log_error_write(srv, __FILE__, __LINE__, "s",
"unexpected value for userdir.include-user; expected list of \"suffix\"");
return HANDLER_ERROR;
}
}
return HANDLER_GO_ON;
}
#define PATCH(x) \
p->conf.x = s->x;
static int mod_userdir_patch_connection(server *srv, connection *con, plugin_data *p) {
size_t i, j;
plugin_config *s = p->config_storage[0];
PATCH(path);
PATCH(exclude_user);
PATCH(include_user);
PATCH(basepath);
PATCH(letterhomes);
PATCH(active);
/* skip the first, the global context */
for (i = 1; i < srv->config_context->used; i++) {
data_config *dc = (data_config *)srv->config_context->data[i];
s = p->config_storage[i];
/* condition didn't match */
if (!config_check_cond(srv, con, dc)) continue;
/* merge config */
for (j = 0; j < dc->value->used; j++) {
data_unset *du = dc->value->data[j];
if (buffer_is_equal_string(du->key, CONST_STR_LEN("userdir.path"))) {
PATCH(path);
} else if (buffer_is_equal_string(du->key, CONST_STR_LEN("userdir.exclude-user"))) {
PATCH(exclude_user);
} else if (buffer_is_equal_string(du->key, CONST_STR_LEN("userdir.include-user"))) {
PATCH(include_user);
} else if (buffer_is_equal_string(du->key, CONST_STR_LEN("userdir.basepath"))) {
PATCH(basepath);
} else if (buffer_is_equal_string(du->key, CONST_STR_LEN("userdir.letterhomes"))) {
PATCH(letterhomes);
} else if (buffer_is_equal_string(du->key, CONST_STR_LEN("userdir.active"))) {
PATCH(active);
}
}
}
return 0;
}
#undef PATCH
URIHANDLER_FUNC(mod_userdir_docroot_handler) {
plugin_data *p = p_d;
size_t k;
char *rel_url;
#ifdef HAVE_PWD_H
struct passwd *pwd = NULL;
#endif
if (buffer_is_empty(con->uri.path)) return HANDLER_GO_ON;
mod_userdir_patch_connection(srv, con, p);
/* enforce the userdir.path to be set in the config, ugly fix for #1587;
* should be replaced with a clean .enabled option in 1.5
*/
if (!p->conf.active || buffer_is_empty(p->conf.path)) return HANDLER_GO_ON;
/* /~user/foo.html -> /home/user/public_html/foo.html */
if (con->uri.path->ptr[0] != '/' ||
con->uri.path->ptr[1] != '~') return HANDLER_GO_ON;
if (NULL == (rel_url = strchr(con->uri.path->ptr + 2, '/'))) {
/* / is missing -> redirect to .../ as we are a user - DIRECTORY ! :) */
http_response_redirect_to_directory(srv, con);
return HANDLER_FINISHED;
}
/* /~/ is a empty username, catch it directly */
if (0 == rel_url - (con->uri.path->ptr + 2)) {
return HANDLER_GO_ON;
}
buffer_copy_string_len(p->username, con->uri.path->ptr + 2, rel_url - (con->uri.path->ptr + 2));
if (buffer_string_is_empty(p->conf.basepath)
#ifdef HAVE_PWD_H
&& NULL == (pwd = getpwnam(p->username->ptr))
#endif
) {
/* user not found */
return HANDLER_GO_ON;
}
for (k = 0; k < p->conf.exclude_user->used; k++) {
data_string *ds = (data_string *)p->conf.exclude_user->data[k];
if (buffer_is_equal(ds->value, p->username)) {
/* user in exclude list */
return HANDLER_GO_ON;
}
}
if (p->conf.include_user->used) {
int found_user = 0;
for (k = 0; k < p->conf.include_user->used; k++) {
data_string *ds = (data_string *)p->conf.include_user->data[k];
if (buffer_is_equal(ds->value, p->username)) {
/* user in include list */
found_user = 1;
break;
}
}
if (!found_user) return HANDLER_GO_ON;
}
/* we build the physical path */
buffer_clear(p->temp_path);
if (buffer_string_is_empty(p->conf.basepath)) {
#ifdef HAVE_PWD_H
buffer_copy_string(p->temp_path, pwd->pw_dir);
#endif
} else {
char *cp = p->username->ptr;
/* check if the username is valid
* a request for /~../ should lead to a directory traversal
* limiting to [-_a-z0-9.] should fix it */
if (cp[0] == '.' && (cp[1] == '\0' || (cp[1] == '.' && cp[2] == '\0'))) {
return HANDLER_GO_ON;
}
for (; *cp; cp++) {
char c = *cp;
if (!(light_isalnum(c) || c == '-' || c == '_' || c == '.')) {
return HANDLER_GO_ON;
}
}
if (con->conf.force_lowercase_filenames) {
buffer_to_lower(p->username);
}
buffer_copy_buffer(p->temp_path, p->conf.basepath);
if (p->conf.letterhomes) {
if (p->username->ptr[0] == '.') return HANDLER_GO_ON;
buffer_append_path_len(p->temp_path, p->username->ptr, 1);
}
buffer_append_path_len(p->temp_path, CONST_BUF_LEN(p->username));
}
buffer_append_path_len(p->temp_path, CONST_BUF_LEN(p->conf.path));
if (buffer_string_is_empty(p->conf.basepath)) {
struct stat st;
int ret;
ret = stat(p->temp_path->ptr, &st);
if (ret < 0 || S_ISDIR(st.st_mode) != 1) {
return HANDLER_GO_ON;
}
}
buffer_copy_buffer(con->physical.basedir, p->temp_path);
/* the physical rel_path is basically the same as uri.path;
* but it is converted to lowercase in case of force_lowercase_filenames and some special handling
* for trailing '.', ' ' and '/' on windows
* we assume that no docroot/physical handler changed this
* (docroot should only set the docroot/server name, phyiscal should only change the phyiscal.path;
* the exception mod_secdownload doesn't work with userdir anyway)
*/
buffer_append_slash(p->temp_path);
/* if no second '/' is found, we assume that it was stripped from the uri.path for the special handling
* on windows.
* we do not care about the trailing slash here on windows, as we already ensured it is a directory
*
* TODO: what to do with trailing dots in usernames on windows? they may result in the same directory
* as a username without them.
*/
if (NULL != (rel_url = strchr(con->physical.rel_path->ptr + 2, '/'))) {
buffer_append_string(p->temp_path, rel_url + 1); /* skip the / */
}
buffer_copy_buffer(con->physical.path, p->temp_path);
return HANDLER_GO_ON;
}
/* this function is called at dlopen() time and inits the callbacks */
int mod_userdir_plugin_init(plugin *p);
int mod_userdir_plugin_init(plugin *p) {
p->version = LIGHTTPD_VERSION_ID;
p->name = buffer_init_string("userdir");
p->init = mod_userdir_init;
p->handle_physical = mod_userdir_docroot_handler;
p->set_defaults = mod_userdir_set_defaults;
p->cleanup = mod_userdir_free;
p->data = NULL;
return 0;
}
↑ V522 There might be dereferencing of a potential null pointer 'p'. Check lines: 48, 46.
↑ V522 There might be dereferencing of a potential null pointer 's'. Check lines: 111, 110.
↑ V522 There might be dereferencing of a potential null pointer 'p->config_storage'. Check lines: 127, 104.
↑ V595 The 'p->username' pointer was utilized before it was verified against nullptr. Check lines: 293, 295.