#include "first.h"
#include <string.h>
#include <stdlib.h>
#include "gw_backend.h"
#include "base.h"
#include "array.h"
#include "buffer.h"
#include "http_kv.h"
#include "http_header.h"
#include "log.h"
#include "sock_addr.h"
#include "status_counter.h"
/**
*
* HTTP reverse proxy
*
* TODO: - HTTP/1.1
* - HTTP/1.1 persistent connection with upstream servers
*/
/* (future: might split struct and move part to http-header-glue.c) */
typedef struct http_header_remap_opts {
const array *urlpaths;
const array *hosts_request;
const array *hosts_response;
int https_remap;
int upgrade;
int connect_method;
/*(not used in plugin_config, but used in handler_ctx)*/
const buffer *http_host;
const buffer *forwarded_host;
const data_string *forwarded_urlpath;
} http_header_remap_opts;
typedef enum {
PROXY_FORWARDED_NONE = 0x00,
PROXY_FORWARDED_FOR = 0x01,
PROXY_FORWARDED_PROTO = 0x02,
PROXY_FORWARDED_HOST = 0x04,
PROXY_FORWARDED_BY = 0x08,
PROXY_FORWARDED_REMOTE_USER = 0x10
} proxy_forwarded_t;
typedef struct {
gw_plugin_config gw;
array *forwarded_params;
array *header_params;
unsigned short replace_http_host;
unsigned int forwarded;
http_header_remap_opts header;
} plugin_config;
typedef struct {
PLUGIN_DATA;
plugin_config **config_storage;
plugin_config conf;
} plugin_data;
static int proxy_check_extforward;
typedef struct {
gw_handler_ctx gw;
http_response_opts opts;
plugin_config conf;
} handler_ctx;
INIT_FUNC(mod_proxy_init) {
plugin_data *p;
p = calloc(1, sizeof(*p));
return p;
}
FREE_FUNC(mod_proxy_free) {
plugin_data *p = p_d;
UNUSED(srv);
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->forwarded_params);
array_free(s->header_params);
/*assert(0 == offsetof(s->gw));*/
gw_plugin_config_free(&s->gw);
/*free(s);*//*free'd by gw_plugin_config_free()*/
}
free(p->config_storage);
}
free(p);
return HANDLER_GO_ON;
}
SETDEFAULTS_FUNC(mod_proxy_set_defaults) {
plugin_data *p = p_d;
data_unset *du;
size_t i = 0;
config_values_t cv[] = {
{ "proxy.server", NULL, T_CONFIG_LOCAL, T_CONFIG_SCOPE_CONNECTION }, /* 0 */
{ "proxy.debug", NULL, T_CONFIG_SHORT, T_CONFIG_SCOPE_CONNECTION }, /* 1 */
{ "proxy.balance", NULL, T_CONFIG_LOCAL, T_CONFIG_SCOPE_CONNECTION }, /* 2 */
{ "proxy.replace-http-host", NULL, T_CONFIG_BOOLEAN, T_CONFIG_SCOPE_CONNECTION }, /* 3 */
{ "proxy.forwarded", NULL, T_CONFIG_ARRAY, T_CONFIG_SCOPE_CONNECTION }, /* 4 */
{ "proxy.header", NULL, T_CONFIG_ARRAY, T_CONFIG_SCOPE_CONNECTION }, /* 5 */
{ "proxy.map-extensions", NULL, T_CONFIG_ARRAY, T_CONFIG_SCOPE_CONNECTION }, /* 6 */
{ NULL, NULL, T_CONFIG_UNSET, T_CONFIG_SCOPE_UNSET }
};
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->gw.debug = 0;
s->replace_http_host = 0;
s->forwarded_params = array_init();
s->forwarded = PROXY_FORWARDED_NONE;
s->header_params = array_init();
s->gw.ext_mapping = array_init();
cv[0].destination = NULL; /* T_CONFIG_LOCAL */
cv[1].destination = &(s->gw.debug);
cv[2].destination = NULL; /* T_CONFIG_LOCAL */
cv[3].destination = &(s->replace_http_host);
cv[4].destination = s->forwarded_params;
cv[5].destination = s->header_params;
cv[6].destination = s->gw.ext_mapping;
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;
}
du = array_get_element(config->value, "proxy.server");
if (!gw_set_defaults_backend(srv, (gw_plugin_data *)p, du, i, 0)) {
return HANDLER_ERROR;
}
du = array_get_element(config->value, "proxy.balance");
if (!gw_set_defaults_balance(srv, &s->gw, du)) {
return HANDLER_ERROR;
}
/* disable check-local for all exts (default enabled) */
if (s->gw.exts) { /*(check after gw_set_defaults_backend())*/
for (size_t j = 0; j < s->gw.exts->used; ++j) {
gw_extension *ex = s->gw.exts->exts[j];
for (size_t n = 0; n < ex->used; ++n) {
ex->hosts[n]->check_local = 0;
}
}
}
if (!array_is_kvany(s->forwarded_params)) {
log_error_write(srv, __FILE__, __LINE__, "s",
"unexpected value for proxy.forwarded; expected ( \"param\" => \"value\" )");
return HANDLER_ERROR;
}
for (size_t j = 0, used = s->forwarded_params->used; j < used; ++j) {
proxy_forwarded_t param;
du = s->forwarded_params->data[j];
if (buffer_is_equal_string(du->key, CONST_STR_LEN("by"))) {
param = PROXY_FORWARDED_BY;
} else if (buffer_is_equal_string(du->key, CONST_STR_LEN("for"))) {
param = PROXY_FORWARDED_FOR;
} else if (buffer_is_equal_string(du->key, CONST_STR_LEN("host"))) {
param = PROXY_FORWARDED_HOST;
} else if (buffer_is_equal_string(du->key, CONST_STR_LEN("proto"))) {
param = PROXY_FORWARDED_PROTO;
} else if (buffer_is_equal_string(du->key, CONST_STR_LEN("remote_user"))) {
param = PROXY_FORWARDED_REMOTE_USER;
} else {
log_error_write(srv, __FILE__, __LINE__, "sb",
"proxy.forwarded keys must be one of: by, for, host, proto, remote_user, but not:", du->key);
return HANDLER_ERROR;
}
if (du->type == TYPE_STRING) {
data_string *ds = (data_string *)du;
if (buffer_is_equal_string(ds->value, CONST_STR_LEN("enable"))) {
s->forwarded |= param;
} else if (!buffer_is_equal_string(ds->value, CONST_STR_LEN("disable"))) {
log_error_write(srv, __FILE__, __LINE__, "sb",
"proxy.forwarded values must be one of: 0, 1, enable, disable; error for key:", du->key);
return HANDLER_ERROR;
}
} else if (du->type == TYPE_INTEGER) {
data_integer *di = (data_integer *)du;
if (di->value) s->forwarded |= param;
} else {
log_error_write(srv, __FILE__, __LINE__, "sb",
"proxy.forwarded values must be one of: 0, 1, enable, disable; error for key:", du->key);
return HANDLER_ERROR;
}
}
if (!array_is_kvany(s->header_params)) {
log_error_write(srv, __FILE__, __LINE__, "s",
"unexpected value for proxy.header; expected ( \"param\" => ( \"key\" => \"value\" ) )");
return HANDLER_ERROR;
}
for (size_t j = 0, used = s->header_params->used; j < used; ++j) {
data_array *da = (data_array *)s->header_params->data[j];
if (buffer_is_equal_string(da->key, CONST_STR_LEN("https-remap"))) {
data_string *ds = (data_string *)da;
if (ds->type != TYPE_STRING) {
log_error_write(srv, __FILE__, __LINE__, "s",
"unexpected value for proxy.header; expected \"enable\" or \"disable\" for https-remap");
return HANDLER_ERROR;
}
s->header.https_remap = !buffer_is_equal_string(ds->value, CONST_STR_LEN("disable"))
&& !buffer_is_equal_string(ds->value, CONST_STR_LEN("0"));
continue;
}
else if (buffer_is_equal_string(da->key, CONST_STR_LEN("upgrade"))) {
data_string *ds = (data_string *)da;
if (ds->type != TYPE_STRING) {
log_error_write(srv, __FILE__, __LINE__, "s",
"unexpected value for proxy.header; expected \"upgrade\" => \"enable\" or \"disable\"");
return HANDLER_ERROR;
}
s->header.upgrade = !buffer_is_equal_string(ds->value, CONST_STR_LEN("disable"))
&& !buffer_is_equal_string(ds->value, CONST_STR_LEN("0"));
continue;
}
else if (buffer_is_equal_string(da->key, CONST_STR_LEN("connect"))) {
data_string *ds = (data_string *)da;
if (ds->type != TYPE_STRING) {
log_error_write(srv, __FILE__, __LINE__, "s",
"unexpected value for proxy.header; expected \"connect\" => \"enable\" or \"disable\"");
return HANDLER_ERROR;
}
s->header.connect_method = !buffer_is_equal_string(ds->value, CONST_STR_LEN("disable"))
&& !buffer_is_equal_string(ds->value, CONST_STR_LEN("0"));
continue;
}
if (da->type != TYPE_ARRAY || !array_is_kvstring(da->value)) {
log_error_write(srv, __FILE__, __LINE__, "sb",
"unexpected value for proxy.header; expected ( \"param\" => ( \"key\" => \"value\" ) ) near key", da->key);
return HANDLER_ERROR;
}
if (buffer_is_equal_string(da->key, CONST_STR_LEN("map-urlpath"))) {
s->header.urlpaths = da->value;
}
else if (buffer_is_equal_string(da->key, CONST_STR_LEN("map-host-request"))) {
s->header.hosts_request = da->value;
}
else if (buffer_is_equal_string(da->key, CONST_STR_LEN("map-host-response"))) {
s->header.hosts_response = da->value;
}
else {
log_error_write(srv, __FILE__, __LINE__, "sb",
"unexpected key for proxy.header; expected ( \"param\" => ( \"key\" => \"value\" ) ) near key", da->key);
return HANDLER_ERROR;
}
}
}
for (i = 0; i < srv->srvconf.modules->used; i++) {
data_string *ds = (data_string *)srv->srvconf.modules->data[i];
if (buffer_is_equal_string(ds->value, CONST_STR_LEN("mod_extforward"))) {
proxy_check_extforward = 1;
break;
}
}
return HANDLER_GO_ON;
}
/* (future: might move to http-header-glue.c) */
static const buffer * http_header_remap_host_match (buffer *b, size_t off, http_header_remap_opts *remap_hdrs, int is_req, size_t alen)
{
const array *hosts = is_req
? remap_hdrs->hosts_request
: remap_hdrs->hosts_response;
if (hosts) {
const char * const s = b->ptr+off;
for (size_t i = 0, used = hosts->used; i < used; ++i) {
const data_string * const ds = (data_string *)hosts->data[i];
const buffer *k = ds->key;
size_t mlen = buffer_string_length(k);
if (1 == mlen && k->ptr[0] == '-') {
/* match with authority provided in Host (if is_req)
* (If no Host in client request, then matching against empty
* string will probably not match, and no remap will be
* performed) */
k = is_req
? remap_hdrs->http_host
: remap_hdrs->forwarded_host;
if (NULL == k) continue;
mlen = buffer_string_length(k);
}
if (mlen == alen && 0 == strncasecmp(s, k->ptr, alen)) {
if (buffer_is_equal_string(ds->value, CONST_STR_LEN("-"))) {
return remap_hdrs->http_host;
}
else if (!buffer_string_is_empty(ds->value)) {
/*(save first matched request host for response match)*/
if (is_req && NULL == remap_hdrs->forwarded_host)
remap_hdrs->forwarded_host = ds->value;
return ds->value;
} /*(else leave authority as-is and stop matching)*/
break;
}
}
}
return NULL;
}
/* (future: might move to http-header-glue.c) */
static size_t http_header_remap_host (buffer *b, size_t off, http_header_remap_opts *remap_hdrs, int is_req, size_t alen)
{
const buffer * const m =
http_header_remap_host_match(b, off, remap_hdrs, is_req, alen);
if (NULL == m) return alen; /*(no match; return original authority length)*/
buffer_substr_replace(b, off, alen, m);
return buffer_string_length(m); /*(length of replacement authority)*/
}
/* (future: might move to http-header-glue.c) */
static size_t http_header_remap_urlpath (buffer *b, size_t off, http_header_remap_opts *remap_hdrs, int is_req)
{
const array *urlpaths = remap_hdrs->urlpaths;
if (urlpaths) {
const char * const s = b->ptr+off;
const size_t plen = buffer_string_length(b) - off; /*(urlpath len)*/
if (is_req) { /* request */
for (size_t i = 0, used = urlpaths->used; i < used; ++i) {
const data_string * const ds = (data_string *)urlpaths->data[i];
const size_t mlen = buffer_string_length(ds->key);
if (mlen <= plen && 0 == memcmp(s, ds->key->ptr, mlen)) {
if (NULL == remap_hdrs->forwarded_urlpath)
remap_hdrs->forwarded_urlpath = ds;
buffer_substr_replace(b, off, mlen, ds->value);
return buffer_string_length(ds->value);/*(replacement len)*/
}
}
}
else { /* response; perform reverse map */
if (NULL != remap_hdrs->forwarded_urlpath) {
const data_string * const ds = remap_hdrs->forwarded_urlpath;
const size_t mlen = buffer_string_length(ds->value);
if (mlen <= plen && 0 == memcmp(s, ds->value->ptr, mlen)) {
buffer_substr_replace(b, off, mlen, ds->key);
return buffer_string_length(ds->key); /*(replacement len)*/
}
}
for (size_t i = 0, used = urlpaths->used; i < used; ++i) {
const data_string * const ds = (data_string *)urlpaths->data[i];
const size_t mlen = buffer_string_length(ds->value);
if (mlen <= plen && 0 == memcmp(s, ds->value->ptr, mlen)) {
buffer_substr_replace(b, off, mlen, ds->key);
return buffer_string_length(ds->key); /*(replacement len)*/
}
}
}
}
return 0;
}
/* (future: might move to http-header-glue.c) */
static void http_header_remap_uri (buffer *b, size_t off, http_header_remap_opts *remap_hdrs, int is_req)
{
/* find beginning of URL-path (might be preceded by scheme://authority
* (caller should make sure any leading whitespace is prior to offset) */
if (b->ptr[off] != '/') {
char *s = b->ptr+off;
size_t alen; /*(authority len (host len))*/
size_t slen; /*(scheme len)*/
const buffer *m;
/* skip over scheme and authority of URI to find beginning of URL-path
* (value might conceivably be relative URL-path instead of URI) */
if (NULL == (s = strchr(s, ':')) || s[1] != '/' || s[2] != '/') return;
slen = s - (b->ptr+off);
s += 3;
off = (size_t)(s - b->ptr);
if (NULL != (s = strchr(s, '/'))) {
alen = (size_t)(s - b->ptr) - off;
if (0 == alen) return; /*(empty authority, e.g. "http:///")*/
}
else {
alen = buffer_string_length(b) - off;
if (0 == alen) return; /*(empty authority, e.g. "http:///")*/
buffer_append_string_len(b, CONST_STR_LEN("/"));
}
/* remap authority (if configured) and set offset to url-path */
m = http_header_remap_host_match(b, off, remap_hdrs, is_req, alen);
if (NULL != m) {
if (remap_hdrs->https_remap
&& (is_req ? 5==slen && 0==memcmp(b->ptr+off-slen-3,"https",5)
: 4==slen && 0==memcmp(b->ptr+off-slen-3,"http",4))){
if (is_req) {
memcpy(b->ptr+off-slen-3+4,"://",3); /*("https"=>"http")*/
--off;
++alen;
}
else {/*(!is_req)*/
memcpy(b->ptr+off-slen-3+4,"s://",4); /*("http" =>"https")*/
++off;
--alen;
}
}
buffer_substr_replace(b, off, alen, m);
alen = buffer_string_length(m);/*(length of replacement authority)*/
}
off += alen;
}
/* remap URLs (if configured) */
http_header_remap_urlpath(b, off, remap_hdrs, is_req);
}
/* (future: might move to http-header-glue.c) */
static void http_header_remap_setcookie (buffer *b, size_t off, http_header_remap_opts *remap_hdrs)
{
/* Given the special-case of Set-Cookie and the (too) loosely restricted
* characters allowed, for best results, the Set-Cookie value should be the
* entire string in b from offset to end of string. In response headers,
* lighttpd may concatenate multiple Set-Cookie headers into single entry
* in con->response.headers, separated by "\r\nSet-Cookie: " */
for (char *s = b->ptr+off, *e; *s; s = e) {
size_t len;
{
while (*s != ';' && *s != '\n' && *s != '\0') ++s;
if (*s == '\n') {
/*(include +1 for '\n', but leave ' ' for ++s below)*/
s += sizeof("Set-Cookie:");
}
if ('\0' == *s) return;
do { ++s; } while (*s == ' ' || *s == '\t');
if ('\0' == *s) return;
e = s+1;
if ('=' == *s) continue;
/*(interested only in Domain and Path attributes)*/
while (*e != '=' && *e != '\0') ++e;
if ('\0' == *e) return;
++e;
switch ((int)(e - s - 1)) {
case 4:
if (0 == strncasecmp(s, "path", 4)) {
if (*e == '"') ++e;
if (*e != '/') continue;
off = (size_t)(e - b->ptr);
len = http_header_remap_urlpath(b, off, remap_hdrs, 0);
e = b->ptr+off+len; /*(b may have been reallocated)*/
continue;
}
break;
case 6:
if (0 == strncasecmp(s, "domain", 6)) {
size_t alen = 0;
if (*e == '"') ++e;
if (*e == '.') ++e;
if (*e == ';') continue;
off = (size_t)(e - b->ptr);
for (char c; (c = e[alen]) != ';' && c != ' ' && c != '\t'
&& c != '\r' && c != '\0'; ++alen);
len = http_header_remap_host(b, off, remap_hdrs, 0, alen);
e = b->ptr+off+len; /*(b may have been reallocated)*/
continue;
}
break;
default:
break;
}
}
}
}
static void buffer_append_string_backslash_escaped(buffer *b, const char *s, size_t len) {
/* (future: might move to buffer.c) */
size_t j = 0;
char *p;
buffer_string_prepare_append(b, len*2 + 4);
p = b->ptr + buffer_string_length(b);
for (size_t i = 0; i < len; ++i) {
int c = s[i];
if (c == '"' || c == '\\' || c == 0x7F || (c < 0x20 && c != '\t'))
p[j++] = '\\';
p[j++] = c;
}
buffer_commit(b, j);
}
static void proxy_set_Forwarded(connection *con, const unsigned int flags) {
buffer *b = NULL, *efor = NULL, *eproto = NULL, *ehost = NULL;
int semicolon = 0;
if (proxy_check_extforward) {
efor =
http_header_env_get(con, CONST_STR_LEN("_L_EXTFORWARD_ACTUAL_FOR"));
eproto =
http_header_env_get(con, CONST_STR_LEN("_L_EXTFORWARD_ACTUAL_PROTO"));
ehost =
http_header_env_get(con, CONST_STR_LEN("_L_EXTFORWARD_ACTUAL_HOST"));
}
/* note: set "Forwarded" prior to updating X-Forwarded-For (below) */
if (flags)
b = http_header_request_get(con, HTTP_HEADER_FORWARDED, CONST_STR_LEN("Forwarded"));
if (flags && NULL == b) {
buffer *xff =
http_header_request_get(con, HTTP_HEADER_X_FORWARDED_FOR, CONST_STR_LEN("X-Forwarded-For"));
http_header_request_set(con, HTTP_HEADER_FORWARDED,
CONST_STR_LEN("Forwarded"),
CONST_STR_LEN("x")); /*(must not be blank for _get below)*/
#ifdef __COVERITY__
force_assert(NULL != b); /*(not NULL because created directly above)*/
#endif
b = http_header_request_get(con, HTTP_HEADER_FORWARDED, CONST_STR_LEN("Forwarded"));
buffer_clear(b);
if (NULL != xff) {
/* use X-Forwarded-For contents to seed Forwarded */
char *s = xff->ptr;
size_t used = buffer_string_length(xff);
for (size_t i=0, j, ipv6; i < used; ++i) {
while (s[i] == ' ' || s[i] == '\t' || s[i] == ',') ++i;
if (s[i] == '\0') break;
j = i;
do {
++i;
} while (s[i]!=' ' && s[i]!='\t' && s[i]!=',' && s[i]!='\0');
buffer_append_string_len(b, CONST_STR_LEN("for="));
/* over-simplified test expecting only IPv4 or IPv6 addresses,
* (not expecting :port, so treat existence of colon as IPv6,
* and not expecting unix paths, especially not containing ':')
* quote all strings, backslash-escape since IPs not validated*/
ipv6 = (NULL != memchr(s+j, ':', i-j)); /*(over-simplified) */
buffer_append_string_len(b, CONST_STR_LEN("\""));
if (ipv6)
buffer_append_string_len(b, CONST_STR_LEN("["));
buffer_append_string_backslash_escaped(b, s+j, i-j);
if (ipv6)
buffer_append_string_len(b, CONST_STR_LEN("]"));
buffer_append_string_len(b, CONST_STR_LEN("\""));
buffer_append_string_len(b, CONST_STR_LEN(", "));
}
}
} else if (flags) { /*(NULL != b)*/
buffer_append_string_len(b, CONST_STR_LEN(", "));
}
if (flags & PROXY_FORWARDED_FOR) {
int family = sock_addr_get_family(&con->dst_addr);
buffer_append_string_len(b, CONST_STR_LEN("for="));
if (NULL != efor) {
/* over-simplified test expecting only IPv4 or IPv6 addresses,
* (not expecting :port, so treat existence of colon as IPv6,
* and not expecting unix paths, especially not containing ':')
* quote all strings and backslash-escape since IPs not validated
* (should be IP from original con->dst_addr_buf,
* so trustable and without :port) */
int ipv6 = (NULL != strchr(efor->ptr, ':'));
buffer_append_string_len(b, CONST_STR_LEN("\""));
if (ipv6) buffer_append_string_len(b, CONST_STR_LEN("["));
buffer_append_string_backslash_escaped(
b, CONST_BUF_LEN(efor));
if (ipv6) buffer_append_string_len(b, CONST_STR_LEN("]"));
buffer_append_string_len(b, CONST_STR_LEN("\""));
} else if (family == AF_INET) {
/*(Note: if :port is added, then must be quoted-string:
* e.g. for="...:port")*/
buffer_append_string_buffer(b, con->dst_addr_buf);
} else if (family == AF_INET6) {
buffer_append_string_len(b, CONST_STR_LEN("\"["));
buffer_append_string_buffer(b, con->dst_addr_buf);
buffer_append_string_len(b, CONST_STR_LEN("]\""));
} else {
buffer_append_string_len(b, CONST_STR_LEN("\""));
buffer_append_string_backslash_escaped(
b, CONST_BUF_LEN(con->dst_addr_buf));
buffer_append_string_len(b, CONST_STR_LEN("\""));
}
semicolon = 1;
}
if (flags & PROXY_FORWARDED_BY) {
int family = sock_addr_get_family(&con->srv_socket->addr);
/* Note: getsockname() and inet_ntop() are expensive operations.
* (recommendation: do not to enable by=... unless required)
* future: might use con->srv_socket->srv_token if addr is not
* INADDR_ANY or in6addr_any, but must omit optional :port
* from con->srv_socket->srv_token for consistency */
if (semicolon) buffer_append_string_len(b, CONST_STR_LEN(";"));
buffer_append_string_len(b, CONST_STR_LEN("by="));
buffer_append_string_len(b, CONST_STR_LEN("\""));
#ifdef HAVE_SYS_UN_H
/* special-case: might need to encode unix domain socket path */
if (family == AF_UNIX) {
buffer_append_string_backslash_escaped(
b, CONST_BUF_LEN(con->srv_socket->srv_token));
}
else
#endif
{
sock_addr addr;
socklen_t addrlen = sizeof(addr);
if (0 == getsockname(con->fd,(struct sockaddr *)&addr, &addrlen)) {
sock_addr_stringify_append_buffer(b, &addr);
}
}
buffer_append_string_len(b, CONST_STR_LEN("\""));
semicolon = 1;
}
if (flags & PROXY_FORWARDED_PROTO) {
/* expecting "http" or "https"
* (not checking if quoted-string and encoding needed) */
if (semicolon) buffer_append_string_len(b, CONST_STR_LEN(";"));
buffer_append_string_len(b, CONST_STR_LEN("proto="));
if (NULL != eproto) {
buffer_append_string_buffer(b, eproto);
} else if (con->srv_socket->is_ssl) {
buffer_append_string_len(b, CONST_STR_LEN("https"));
} else {
buffer_append_string_len(b, CONST_STR_LEN("http"));
}
semicolon = 1;
}
if (flags & PROXY_FORWARDED_HOST) {
if (NULL != ehost) {
if (semicolon)
buffer_append_string_len(b, CONST_STR_LEN(";"));
buffer_append_string_len(b, CONST_STR_LEN("host=\""));
buffer_append_string_backslash_escaped(
b, CONST_BUF_LEN(ehost));
buffer_append_string_len(b, CONST_STR_LEN("\""));
semicolon = 1;
} else if (!buffer_string_is_empty(con->request.http_host)) {
if (semicolon)
buffer_append_string_len(b, CONST_STR_LEN(";"));
buffer_append_string_len(b, CONST_STR_LEN("host=\""));
buffer_append_string_backslash_escaped(
b, CONST_BUF_LEN(con->request.http_host));
buffer_append_string_len(b, CONST_STR_LEN("\""));
semicolon = 1;
}
}
if (flags & PROXY_FORWARDED_REMOTE_USER) {
buffer *remote_user =
http_header_env_get(con, CONST_STR_LEN("REMOTE_USER"));
if (NULL != remote_user) {
if (semicolon)
buffer_append_string_len(b, CONST_STR_LEN(";"));
buffer_append_string_len(b, CONST_STR_LEN("remote_user=\""));
buffer_append_string_backslash_escaped(
b, CONST_BUF_LEN(remote_user));
buffer_append_string_len(b, CONST_STR_LEN("\""));
semicolon = 1;
}
}
/* legacy X-* headers, including X-Forwarded-For */
b = (NULL != efor) ? efor : con->dst_addr_buf;
http_header_request_set(con, HTTP_HEADER_X_FORWARDED_FOR,
CONST_STR_LEN("X-Forwarded-For"),
CONST_BUF_LEN(b));
b = (NULL != ehost) ? ehost : con->request.http_host;
if (!buffer_string_is_empty(b)) {
http_header_request_set(con, HTTP_HEADER_OTHER,
CONST_STR_LEN("X-Host"),
CONST_BUF_LEN(b));
http_header_request_set(con, HTTP_HEADER_OTHER,
CONST_STR_LEN("X-Forwarded-Host"),
CONST_BUF_LEN(b));
}
b = (NULL != eproto) ? eproto : con->uri.scheme;
http_header_request_set(con, HTTP_HEADER_X_FORWARDED_PROTO,
CONST_STR_LEN("X-Forwarded-Proto"),
CONST_BUF_LEN(b));
}
static handler_t proxy_create_env(server *srv, gw_handler_ctx *gwhctx) {
handler_ctx *hctx = (handler_ctx *)gwhctx;
connection *con = hctx->gw.remote_conn;
const int remap_headers = (NULL != hctx->conf.header.urlpaths
|| NULL != hctx->conf.header.hosts_request);
const int upgrade = hctx->conf.header.upgrade
&& (NULL != http_header_request_get(con, HTTP_HEADER_UPGRADE, CONST_STR_LEN("Upgrade")));
size_t rsz = (size_t)(con->read_queue->bytes_out - hctx->gw.wb->bytes_in);
buffer * const b = chunkqueue_prepend_buffer_open_sz(hctx->gw.wb, rsz < 65536 ? rsz : con->header_len);
/* build header */
/* request line */
http_method_append(b, con->request.http_method);
buffer_append_string_len(b, CONST_STR_LEN(" "));
buffer_append_string_buffer(b, con->request.uri);
if (remap_headers)
http_header_remap_uri(b, buffer_string_length(b) - buffer_string_length(con->request.uri), &hctx->conf.header, 1);
if (!upgrade)
buffer_append_string_len(b, CONST_STR_LEN(" HTTP/1.0\r\n"));
else
buffer_append_string_len(b, CONST_STR_LEN(" HTTP/1.1\r\n"));
if (hctx->conf.replace_http_host && !buffer_string_is_empty(hctx->gw.host->id)) {
if (hctx->gw.conf.debug > 1) {
log_error_write(srv, __FILE__, __LINE__, "SBS",
"proxy - using \"", hctx->gw.host->id, "\" as HTTP Host");
}
buffer_append_string_len(b, CONST_STR_LEN("Host: "));
buffer_append_string_buffer(b, hctx->gw.host->id);
buffer_append_string_len(b, CONST_STR_LEN("\r\n"));
} else if (!buffer_string_is_empty(con->request.http_host)) {
buffer_append_string_len(b, CONST_STR_LEN("Host: "));
buffer_append_string_buffer(b, con->request.http_host);
if (remap_headers) {
size_t alen = buffer_string_length(con->request.http_host);
http_header_remap_host(b, buffer_string_length(b) - alen, &hctx->conf.header, 1, alen);
}
buffer_append_string_len(b, CONST_STR_LEN("\r\n"));
}
/* "Forwarded" and legacy X- headers */
proxy_set_Forwarded(con, hctx->conf.forwarded);
if (HTTP_METHOD_GET != con->request.http_method
&& HTTP_METHOD_HEAD != con->request.http_method
&& con->request.content_length >= 0) {
/* set Content-Length if client sent Transfer-Encoding: chunked
* and not streaming to backend (request body has been fully received) */
buffer *vb = http_header_request_get(con, HTTP_HEADER_CONTENT_LENGTH, CONST_STR_LEN("Content-Length"));
if (NULL == vb) {
char buf[LI_ITOSTRING_LENGTH];
li_itostrn(buf, sizeof(buf), con->request.content_length);
http_header_request_set(con, HTTP_HEADER_CONTENT_LENGTH, CONST_STR_LEN("Content-Length"), buf, strlen(buf));
}
}
/* request header */
for (size_t i = 0, used = con->request.headers->used; i < used; ++i) {
data_string *ds = (data_string *)con->request.headers->data[i];
const size_t klen = buffer_string_length(ds->key);
size_t vlen;
switch (klen) {
default:
break;
case 4:
if (buffer_is_equal_caseless_string(ds->key, CONST_STR_LEN("Host"))) continue; /*(handled further above)*/
break;
case 10:
if (buffer_is_equal_caseless_string(ds->key, CONST_STR_LEN("Connection"))) continue;
if (buffer_is_equal_caseless_string(ds->key, CONST_STR_LEN("Set-Cookie"))) continue; /*(response header only; avoid accidental reflection)*/
break;
case 16:
if (buffer_is_equal_caseless_string(ds->key, CONST_STR_LEN("Proxy-Connection"))) continue;
break;
case 5:
/* Do not emit HTTP_PROXY in environment.
* Some executables use HTTP_PROXY to configure
* outgoing proxy. See also https://httpoxy.org/ */
if (buffer_is_equal_caseless_string(ds->key, CONST_STR_LEN("Proxy"))) continue;
break;
case 0:
continue;
}
vlen = buffer_string_length(ds->value);
if (0 == vlen) continue;
if (buffer_string_space(b) < klen + vlen + 4) {
size_t extend = b->size * 2 - buffer_string_length(b);
extend = extend > klen + vlen + 4 ? extend : klen + vlen + 4 + 4095;
buffer_string_prepare_append(b, extend);
}
buffer_append_string_len(b, ds->key->ptr, klen);
buffer_append_string_len(b, CONST_STR_LEN(": "));
buffer_append_string_len(b, ds->value->ptr, vlen);
buffer_append_string_len(b, CONST_STR_LEN("\r\n"));
if (!remap_headers) continue;
/* check for hdrs for which to remap URIs in-place after append to b */
switch (klen) {
default:
continue;
#if 0 /* "URI" is HTTP response header (non-standard; historical in Apache) */
case 3:
if (buffer_is_equal_caseless_string(ds->key, CONST_STR_LEN("URI"))) break;
continue;
#endif
#if 0 /* "Location" is HTTP response header */
case 8:
if (buffer_is_equal_caseless_string(ds->key, CONST_STR_LEN("Location"))) break;
continue;
#endif
case 11: /* "Destination" is WebDAV request header */
if (buffer_is_equal_caseless_string(ds->key, CONST_STR_LEN("Destination"))) break;
continue;
case 16: /* "Content-Location" may be HTTP request or response header */
if (buffer_is_equal_caseless_string(ds->key, CONST_STR_LEN("Content-Location"))) break;
continue;
}
http_header_remap_uri(b, buffer_string_length(b) - vlen - 2, &hctx->conf.header, 1);
}
if (!upgrade)
buffer_append_string_len(b, CONST_STR_LEN("Connection: close\r\n\r\n"));
else
buffer_append_string_len(b, CONST_STR_LEN("Connection: close, upgrade\r\n\r\n"));
hctx->gw.wb_reqlen = buffer_string_length(b);
chunkqueue_prepend_buffer_commit(hctx->gw.wb);
if (con->request.content_length) {
chunkqueue_append_chunkqueue(hctx->gw.wb, con->request_content_queue);
if (con->request.content_length > 0)
hctx->gw.wb_reqlen += con->request.content_length; /* total req size */
else /* as-yet-unknown total request size (Transfer-Encoding: chunked)*/
hctx->gw.wb_reqlen = -hctx->gw.wb_reqlen;
}
status_counter_inc(srv, CONST_STR_LEN("proxy.requests"));
return HANDLER_GO_ON;
}
static handler_t proxy_create_env_connect(server *srv, gw_handler_ctx *gwhctx) {
handler_ctx *hctx = (handler_ctx *)gwhctx;
connection *con = hctx->gw.remote_conn;
con->http_status = 200; /* OK */
con->file_started = 1;
gw_set_transparent(srv, &hctx->gw);
http_response_upgrade_read_body_unknown(srv, con);
status_counter_inc(srv, CONST_STR_LEN("proxy.requests"));
return HANDLER_GO_ON;
}
#define PATCH(x) \
p->conf.x = s->x;
#define PATCH_GW(x) \
p->conf.gw.x = s->gw.x;
static int mod_proxy_patch_connection(server *srv, connection *con, plugin_data *p) {
size_t i, j;
plugin_config *s = p->config_storage[0];
PATCH_GW(exts);
PATCH_GW(exts_auth);
PATCH_GW(exts_resp);
PATCH_GW(debug);
PATCH_GW(ext_mapping);
PATCH_GW(balance);
PATCH(replace_http_host);
PATCH(forwarded);
PATCH(header); /*(copies struct)*/
/* 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("proxy.server"))) {
PATCH_GW(exts);
PATCH_GW(exts_auth);
PATCH_GW(exts_resp);
} else if (buffer_is_equal_string(du->key, CONST_STR_LEN("proxy.debug"))) {
PATCH_GW(debug);
} else if (buffer_is_equal_string(du->key, CONST_STR_LEN("proxy.balance"))) {
PATCH_GW(balance);
} else if (buffer_is_equal_string(du->key, CONST_STR_LEN("proxy.map-extensions"))) {
PATCH_GW(ext_mapping);
} else if (buffer_is_equal_string(du->key, CONST_STR_LEN("proxy.replace-http-host"))) {
PATCH(replace_http_host);
} else if (buffer_is_equal_string(du->key, CONST_STR_LEN("proxy.forwarded"))) {
PATCH(forwarded);
} else if (buffer_is_equal_string(du->key, CONST_STR_LEN("proxy.header"))) {
PATCH(header); /*(copies struct)*/
}
}
}
return 0;
}
#undef PATCH_GW
#undef PATCH
static handler_t proxy_response_headers(server *srv, connection *con, struct http_response_opts_t *opts) {
/* response headers just completed */
handler_ctx *hctx = (handler_ctx *)opts->pdata;
if (con->response.htags & HTTP_HEADER_UPGRADE) {
if (hctx->conf.header.upgrade && con->http_status == 101) {
/* 101 Switching Protocols; transition to transparent proxy */
gw_set_transparent(srv, &hctx->gw);
http_response_upgrade_read_body_unknown(srv, con);
}
else {
con->response.htags &= ~HTTP_HEADER_UPGRADE;
#if 0
/* preserve prior questionable behavior; likely broken behavior
* anyway if backend thinks connection is being upgraded but client
* does not receive Connection: upgrade */
http_header_response_unset(con, HTTP_HEADER_UPGRADE,
CONST_STR_LEN("Upgrade"))
#endif
}
}
/* rewrite paths, if needed */
if (NULL == hctx->conf.header.urlpaths
&& NULL == hctx->conf.header.hosts_response)
return HANDLER_GO_ON;
if (con->response.htags & HTTP_HEADER_LOCATION) {
buffer *vb = http_header_response_get(con, HTTP_HEADER_LOCATION, CONST_STR_LEN("Location"));
if (vb) http_header_remap_uri(vb, 0, &hctx->conf.header, 0);
}
if (con->response.htags & HTTP_HEADER_CONTENT_LOCATION) {
buffer *vb = http_header_response_get(con, HTTP_HEADER_CONTENT_LOCATION, CONST_STR_LEN("Content-Location"));
if (vb) http_header_remap_uri(vb, 0, &hctx->conf.header, 0);
}
if (con->response.htags & HTTP_HEADER_SET_COOKIE) {
buffer *vb = http_header_response_get(con, HTTP_HEADER_SET_COOKIE, CONST_STR_LEN("Set-Cookie"));
if (vb) http_header_remap_setcookie(vb, 0, &hctx->conf.header);
}
return HANDLER_GO_ON;
}
static handler_t mod_proxy_check_extension(server *srv, connection *con, void *p_d) {
plugin_data *p = p_d;
handler_t rc;
if (con->mode != DIRECT) return HANDLER_GO_ON;
mod_proxy_patch_connection(srv, con, p);
if (NULL == p->conf.gw.exts) return HANDLER_GO_ON;
rc = gw_check_extension(srv, con, (gw_plugin_data *)p, 1, sizeof(handler_ctx));
if (HANDLER_GO_ON != rc) return rc;
if (con->mode == p->id) {
handler_ctx *hctx = con->plugin_ctx[p->id];
hctx->gw.create_env = proxy_create_env;
hctx->gw.response = chunk_buffer_acquire();
hctx->gw.opts.backend = BACKEND_PROXY;
hctx->gw.opts.pdata = hctx;
hctx->gw.opts.headers = proxy_response_headers;
hctx->conf = p->conf; /*(copies struct)*/
hctx->conf.header.http_host = con->request.http_host;
hctx->conf.header.upgrade &= (con->request.http_version == HTTP_VERSION_1_1);
/* mod_proxy currently sends all backend requests as http.
* https-remap is a flag since it might not be needed if backend
* honors Forwarded or X-Forwarded-Proto headers, e.g. by using
* lighttpd mod_extforward or similar functionality in backend*/
if (hctx->conf.header.https_remap) {
hctx->conf.header.https_remap =
buffer_is_equal_string(con->uri.scheme, CONST_STR_LEN("https"));
}
if (con->request.http_method == HTTP_METHOD_CONNECT) {
/*(note: not requiring HTTP/1.1 due to too many non-compliant
* clients such as 'openssl s_client')*/
if (hctx->conf.header.connect_method) {
hctx->gw.create_env = proxy_create_env_connect;
}
else {
con->http_status = 405; /* Method Not Allowed */
con->mode = DIRECT;
return HANDLER_FINISHED;
}
}
}
return HANDLER_GO_ON;
}
int mod_proxy_plugin_init(plugin *p);
int mod_proxy_plugin_init(plugin *p) {
p->version = LIGHTTPD_VERSION_ID;
p->name = buffer_init_string("proxy");
p->init = mod_proxy_init;
p->cleanup = mod_proxy_free;
p->set_defaults = mod_proxy_set_defaults;
p->connection_reset = gw_connection_reset;
p->handle_uri_clean = mod_proxy_check_extension;
p->handle_subrequest = gw_handle_subrequest;
p->handle_trigger = gw_handle_trigger;
p->handle_waitpid = gw_handle_waitpid_cb;
p->data = NULL;
return 0;
}
↑ V522 There might be dereferencing of a potential null pointer 's'. Check lines: 132, 131.
↑ V522 There might be dereferencing of a potential null pointer 'p->config_storage'. Check lines: 147, 125.
↑ V641 The size of the '& addr' buffer is not a multiple of the element size of the type 'struct sockaddr'.