Fold in ALv2 licensed UWSGI proxy (sub)module as acknowledged via

https://github.com/unbit/uwsgi/issues/1636



git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1810358 13f79535-47bb-0310-9956-ffa450edef68

modules/proxy/mod_proxy_uwsgi.c

@@ -0,0 +1,520 @@
+/* Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+        
+*** mod_proxy_uwsgi ***
+
+Copyright 2009-2017 Unbit S.a.s. <info@unbit.it>
+     
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+*/
+
+#define APR_WANT_MEMFUNC
+#define APR_WANT_STRFUNC
+#include "apr_strings.h"
+#include "apr_hooks.h"
+#include "apr_optional_hooks.h"
+#include "apr_buckets.h"
+
+#include "httpd.h"
+#include "http_config.h"
+#include "http_log.h"
+#include "http_protocol.h"
+#include "http_request.h"
+#include "util_script.h"
+
+#include "mod_proxy.h"
+
+
+#define UWSGI_SCHEME "uwsgi"
+#define UWSGI_DEFAULT_PORT 3031
+
+module AP_MODULE_DECLARE_DATA proxy_uwsgi_module;
+
+
+static int uwsgi_canon(request_rec *r, char *url)
+{
+    char *host, sport[sizeof(":65535")];
+    const char *err, *path;
+    apr_port_t port = UWSGI_DEFAULT_PORT;
+
+    if (strncasecmp(url, UWSGI_SCHEME "://", sizeof(UWSGI_SCHEME) + 2)) {
+        return DECLINED;
+    }
+    url += sizeof(UWSGI_SCHEME); /* Keep slashes */
+
+    err = ap_proxy_canon_netloc(r->pool, &url, NULL, NULL, &host, &port);
+    if (err) {
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
+                    "error parsing URL %s: %s", url, err);
+        return HTTP_BAD_REQUEST;
+    }
+
+    if (port != UWSGI_DEFAULT_PORT)
+        apr_snprintf(sport, sizeof(sport), ":%u", port);
+    else
+        sport[0] = '\0';
+
+    if (ap_strchr(host, ':')) { /* if literal IPv6 address */
+        host = apr_pstrcat(r->pool, "[", host, "]", NULL);
+    }
+
+    path = ap_proxy_canonenc(r->pool, url, strlen(url), enc_path, 0,
+                             r->proxyreq);
+    if (!path) {
+        return HTTP_BAD_REQUEST;
+    }
+
+    r->filename = apr_pstrcat(r->pool, "proxy:" UWSGI_SCHEME "://", host, sport, "/",
+                              path, NULL);
+
+    return OK;
+}
+
+
+static int uwsgi_send(proxy_conn_rec *conn, const char *buf, apr_size_t length,
+                   request_rec *r)
+{
+    apr_status_t rv;
+    apr_size_t written;
+
+    while (length > 0) {
+        written = length;
+        if ((rv = apr_socket_send(conn->sock, buf, &written)) != APR_SUCCESS) {
+            ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r,
+                          "sending data to %s:%u failed",
+                          conn->hostname, conn->port);
+            return HTTP_SERVICE_UNAVAILABLE;
+        }
+
+        /* count for stats */
+        conn->worker->s->transferred += written;
+        buf += written;
+        length -= written;
+    }
+
+    return OK;
+}
+
+
+/*
+ * Send uwsgi header block
+ */
+static int uwsgi_send_headers(request_rec *r, proxy_conn_rec *conn)
+{
+    char *buf, *ptr;
+
+    const apr_array_header_t *env_table;
+    const apr_table_entry_t *env;
+
+    int j;
+
+    apr_size_t headerlen = 4;
+    uint16_t pktsize, keylen, vallen;
+
+    ap_add_common_vars(r);
+    ap_add_cgi_vars(r);
+
+    // this is not a security problem (in Linux) as uWSGI destroy the env memory area readable in /proc
+    // and generally if you host untrusted apps in your server and allows them to read others uid /proc/<pid>
+    // files you have higher problems...
+    const char *auth = apr_table_get(r->headers_in, "Authorization");
+    if (auth) {
+        apr_table_setn(r->subprocess_env, "HTTP_AUTHORIZATION", auth); 
+    }
+
+    const char *script_name = apr_table_get(r->subprocess_env, "SCRIPT_NAME");
+    const char *path_info = apr_table_get(r->subprocess_env, "PATH_INFO");
+
+    if (script_name && path_info) {
+        if (strcmp(path_info, "/")) {
+            apr_table_set(r->subprocess_env, "SCRIPT_NAME", apr_pstrndup(r->pool, script_name, strlen(script_name)-strlen(path_info)));
+	}
+        else {
+            if (!strcmp(script_name, "/")) {
+                apr_table_set(r->subprocess_env, "SCRIPT_NAME", "");
+            }
+        }
+    }
+
+    env_table = apr_table_elts(r->subprocess_env);
+    env = (apr_table_entry_t *)env_table->elts;
+
+    for (j = 0; j < env_table->nelts; ++j) {
+        headerlen += 2 + strlen(env[j].key) + 2 + strlen(env[j].val) ;
+    }
+
+    ptr = buf = apr_palloc(r->pool, headerlen);
+
+    ptr+=4;
+
+    for (j = 0; j < env_table->nelts; ++j) {
+	keylen = strlen(env[j].key);
+	*ptr++= (uint8_t) (keylen & 0xff);
+	*ptr++= (uint8_t) ((keylen >> 8)  & 0xff);
+	memcpy(ptr, env[j].key, keylen) ; ptr+=keylen;
+
+	vallen = strlen(env[j].val);
+	*ptr++= (uint8_t) (vallen & 0xff);
+	*ptr++= (uint8_t) ((vallen >> 8)  & 0xff);
+	memcpy(ptr, env[j].val, vallen) ; ptr+=vallen;
+    }
+
+    pktsize = headerlen-4;
+
+    buf[0] = 0;
+    buf[1] = (uint8_t) (pktsize & 0xff);
+    buf[2] = (uint8_t) ((pktsize >> 8) & 0xff);
+    buf[3] = 0;
+
+    return uwsgi_send(conn, buf, headerlen, r);
+}
+
+
+static int uwsgi_send_body(request_rec *r, proxy_conn_rec *conn)
+{
+    if (ap_should_client_block(r)) {
+        char *buf = apr_palloc(r->pool, AP_IOBUFSIZE);
+        int status;
+        apr_size_t readlen;
+
+        readlen = ap_get_client_block(r, buf, AP_IOBUFSIZE);
+        while (readlen > 0) {
+            status = uwsgi_send(conn, buf, readlen, r);
+            if (status != OK) {
+                return HTTP_SERVICE_UNAVAILABLE;
+            }
+            readlen = ap_get_client_block(r, buf, AP_IOBUFSIZE);
+        }
+        if (readlen == -1) {
+            ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
+                          "receiving request body failed");
+            return HTTP_INTERNAL_SERVER_ERROR;
+        }
+    }
+
+    return OK;
+}
+
+static request_rec *make_fake_req(conn_rec *c, request_rec *r)
+{
+    apr_pool_t *pool;
+    request_rec *rp;
+
+    apr_pool_create(&pool, c->pool);
+
+    rp = apr_pcalloc(pool, sizeof(*r));
+
+    rp->pool            = pool;
+    rp->status          = HTTP_OK;
+
+    rp->headers_in      = apr_table_make(pool, 50);
+    rp->subprocess_env  = apr_table_make(pool, 50);
+    rp->headers_out     = apr_table_make(pool, 12);
+    rp->err_headers_out = apr_table_make(pool, 5);
+    rp->notes           = apr_table_make(pool, 5);
+
+    rp->server = r->server;
+    rp->log = r->log;
+    rp->proxyreq = r->proxyreq;
+    rp->request_time = r->request_time;
+    rp->connection      = c;
+    rp->output_filters  = c->output_filters;
+    rp->input_filters   = c->input_filters;
+    rp->proto_output_filters  = c->output_filters;
+    rp->proto_input_filters   = c->input_filters;
+    rp->useragent_ip = c->client_ip;
+    rp->useragent_addr = c->client_addr;
+
+    rp->request_config  = ap_create_request_config(pool);
+    proxy_run_create_req(r, rp);
+
+    return rp;
+}
+
+static int uwsgi_response(request_rec *r, proxy_conn_rec *backend, proxy_server_conf *conf)
+{
+
+	char buffer[HUGE_STRING_LEN];
+	const char *buf;
+	char *value, *end;
+	int len;
+	int backend_broke = 0;
+	apr_status_t rc;
+	conn_rec *c = r->connection;
+	apr_off_t readbytes;
+	apr_status_t rv;
+	apr_bucket *e;
+	apr_read_type_e mode = APR_NONBLOCK_READ;
+
+	request_rec *rp = make_fake_req(backend->connection, r);
+	rp->proxyreq = PROXYREQ_RESPONSE;
+
+	apr_bucket_brigade *bb = apr_brigade_create(r->pool, c->bucket_alloc);
+	apr_bucket_brigade *pass_bb = apr_brigade_create(r->pool, c->bucket_alloc);
+
+	len = ap_getline(buffer, sizeof(buffer), rp, 1);
+
+	if (len <= 0) {
+		// oops
+		return HTTP_INTERNAL_SERVER_ERROR;
+	}
+
+	backend->worker->s->read += len;
+
+	if (len >= sizeof(buffer)-1) {
+		// oops
+		return HTTP_INTERNAL_SERVER_ERROR;
+	}
+	/* Position of http status code */
+	int status_start;
+	if (apr_date_checkmask(buffer, "HTTP/#.# ###*")) {
+		status_start = 9;
+	} else if (apr_date_checkmask(buffer, "HTTP/# ###*")) {
+		status_start = 7;
+	} else {
+		// oops
+		return HTTP_INTERNAL_SERVER_ERROR;
+	}
+	int status_end = status_start + 3;
+
+	char keepchar = buffer[status_end];
+	buffer[status_end] = '\0';
+	r->status = atoi(&buffer[status_start]);
+
+	if (keepchar != '\0') {
+		buffer[status_end] = keepchar;
+	} else {
+		/* 2616 requires the space in Status-Line; the origin
+		* server may have sent one but ap_rgetline_core will
+		* have stripped it. */
+		buffer[status_end] = ' ';
+		buffer[status_end+1] = '\0';
+	}
+	r->status_line = apr_pstrdup(r->pool, &buffer[status_start]);
+
+	// start parsing headers;
+	while ((len = ap_getline(buffer, sizeof(buffer), rp, 1)) > 0) {
+		value = strchr(buffer, ':');
+		// invalid header skip
+		if (!value) continue;
+		*value = '\0';
+		++value;
+		while (apr_isspace(*value)) ++value; 
+		for (end = &value[strlen(value)-1]; end > value && apr_isspace(*end); --end) *end = '\0';
+		apr_table_add(r->headers_out, buffer, value);
+	}
+
+	if ((buf = apr_table_get(r->headers_out, "Content-Type"))) {
+		ap_set_content_type(r, apr_pstrdup(r->pool, buf));
+	}
+
+    // honor ProxyErrorOverride and ErrorDocument
+#if AP_MODULE_MAGIC_AT_LEAST(20101106,0)
+    proxy_dir_conf *dconf = ap_get_module_config(r->per_dir_config, &proxy_module);
+    if (dconf->error_override && ap_is_HTTP_ERROR(r->status)) {
+#else
+    if (conf->error_override && ap_is_HTTP_ERROR(r->status)) {
+#endif
+        int status = r->status;
+        r->status = HTTP_OK;
+        r->status_line = NULL;
+
+        apr_brigade_cleanup(bb);
+               apr_brigade_cleanup(pass_bb);
+
+        return status;
+    }
+
+	int finish = 0;
+	while(!finish) {
+		rv = ap_get_brigade(rp->input_filters, bb,
+                                        AP_MODE_READBYTES, mode,
+                                        conf->io_buffer_size);
+		if (APR_STATUS_IS_EAGAIN(rv)
+                        || (rv == APR_SUCCESS && APR_BRIGADE_EMPTY(bb)) ) {
+			e = apr_bucket_flush_create(c->bucket_alloc);
+			APR_BRIGADE_INSERT_TAIL(bb, e);
+			if (ap_pass_brigade(r->output_filters, bb) || c->aborted) {
+				break;
+			}
+			apr_brigade_cleanup(bb);
+			mode = APR_BLOCK_READ;
+			continue;
+		}
+		else if (rv == APR_EOF) {
+			break;
+		}
+		else if (rv != APR_SUCCESS) {
+			ap_proxy_backend_broke(r, bb);
+			ap_pass_brigade(r->output_filters, bb);
+			backend_broke = 1;
+			break;
+		}
+
+		mode = APR_NONBLOCK_READ;
+		apr_brigade_length(bb, 0, &readbytes);
+		backend->worker->s->read += readbytes;
+
+		if (APR_BRIGADE_EMPTY(bb)) {
+                        apr_brigade_cleanup(bb);
+                        break;
+                }
+
+		ap_proxy_buckets_lifetime_transform(r, bb, pass_bb);
+
+		// found the last brigade?
+		if (APR_BUCKET_IS_EOS(APR_BRIGADE_LAST(bb))) finish = 1;
+
+		// do not pass chunk if it is zero_sized
+		apr_brigade_length(pass_bb, 0, &readbytes);
+
+		if ((readbytes > 0 && ap_pass_brigade(r->output_filters, pass_bb) != APR_SUCCESS) || c->aborted) {
+			finish = 1;
+		}
+
+		apr_brigade_cleanup(bb);
+		apr_brigade_cleanup(pass_bb);
+	}
+
+	e = apr_bucket_eos_create(c->bucket_alloc);
+	APR_BRIGADE_INSERT_TAIL(bb, e);
+        ap_pass_brigade(r->output_filters, bb);
+
+	apr_brigade_cleanup(bb);
+
+	if (c->aborted || backend_broke) {
+        	return DONE;
+        }
+
+	return OK;
+}
+
+static int uwsgi_handler(request_rec *r, proxy_worker *worker,
+                        proxy_server_conf *conf, char *url,
+                        const char *proxyname, apr_port_t proxyport)
+{
+    int status;
+    proxy_conn_rec *backend = NULL;
+    apr_pool_t *p = r->pool;
+    apr_uri_t *uri = apr_palloc(r->pool, sizeof(*uri));
+    char server_portstr[32];
+
+    if (strncasecmp(url, UWSGI_SCHEME "://", sizeof(UWSGI_SCHEME) + 2)) {
+        ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
+                      "declining URL %s", url);
+        return DECLINED;
+    }
+
+    // ADD PATH_INFO
+#if AP_MODULE_MAGIC_AT_LEAST(20111130,0)
+    size_t w_len = strlen(worker->s->name);
+#else
+    size_t w_len = strlen(worker->name);
+#endif
+    char *u_path_info = r->filename + 6 + w_len;
+    int delta = 0;
+    if (u_path_info[0] != '/') {
+        delta = 1;
+    }
+    int decode_status = ap_unescape_url(url+w_len-delta);
+    if (decode_status) {
+       ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
+                      "unable to decode uri: %s",
+                      url+w_len-delta);
+        return HTTP_INTERNAL_SERVER_ERROR;
+    }
+    apr_table_add(r->subprocess_env, "PATH_INFO", url+w_len-delta);
+
+
+    /* Create space for state information */
+    status = ap_proxy_acquire_connection(UWSGI_SCHEME, &backend, worker,
+                                         r->server);
+    if (status != OK) {
+        goto cleanup;
+    }
+    backend->is_ssl = 0;
+
+    /* Step One: Determine Who To Connect To */
+    status = ap_proxy_determine_connection(p, r, conf, worker, backend,
+                                           uri, &url, proxyname, proxyport,
+                                           server_portstr, sizeof(server_portstr));
+    if (status != OK) {
+        goto cleanup;
+    }
+
+
+    /* Step Two: Make the Connection */
+    if (ap_proxy_connect_backend(UWSGI_SCHEME, backend, worker, r->server)) {
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
+                      "failed to make connection to backend: %s:%u",
+                      backend->hostname, backend->port);
+        status = HTTP_SERVICE_UNAVAILABLE;
+        goto cleanup;
+    }
+
+    /* Step Three: Create conn_rec */
+    if (!backend->connection) {
+	if ((status = ap_proxy_connection_create(UWSGI_SCHEME, backend,
+						r->connection, r->server)) != OK)
+		goto cleanup;
+    }
+
+    /* Step Four: Process the Request */
+    if (   ((status = ap_setup_client_block(r, REQUEST_CHUNKED_ERROR)) != OK)
+        || ((status = uwsgi_send_headers(r, backend)) != OK)
+        || ((status = uwsgi_send_body(r, backend)) != OK)
+        || ((status = uwsgi_response(r, backend, conf)) != OK)) {
+        goto cleanup;
+    }
+
+cleanup:
+    if (backend) {
+        backend->close = 1; /* always close the socket */
+        ap_proxy_release_connection(UWSGI_SCHEME, backend, r->server);
+    }
+    return status;
+}
+
+
+static void register_hooks(apr_pool_t *p)
+{
+    proxy_hook_scheme_handler(uwsgi_handler, NULL, NULL, APR_HOOK_FIRST);
+    proxy_hook_canon_handler(uwsgi_canon, NULL, NULL, APR_HOOK_FIRST);
+}
+
+
+module AP_MODULE_DECLARE_DATA proxy_uwsgi_module = {
+    STANDARD20_MODULE_STUFF,
+    NULL,		/* create per-directory config structure */
+    NULL,		/* merge per-directory config structures */
+    NULL,		/* create per-server config structure */
+    NULL,		/* merge per-server config structures */
+    NULL,		/* command table */
+    register_hooks	/* register hooks */
+};