Add in rough uds support (Bugx 54101) from Blaise Tarr <blaise.tarr@gmail.com>

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1451633 13f79535-47bb-0310-9956-ffa450edef68

include/ap_mmn.h

@@ -414,6 +414,7 @@
  *                         add ap_has_cntrl()
  * 20121222.2 (2.5.0-dev)  Add ap_password_validate()
  * 20121222.3 (2.5.0-dev)  Add ppinherit to proxy_server_conf
+ * 20121222.4 (2.5.0-dev)  Add uds_path to proxy_conn_rec
  */
 
 #define MODULE_MAGIC_COOKIE 0x41503235UL /* "AP25" */

modules/proxy/mod_proxy.h

@@ -236,6 +236,7 @@ typedef struct {
                                 * that is used over the backend connection. */
     proxy_worker *worker;      /* Connection pool this connection belongs to */
     apr_pool_t   *pool;        /* Subpool for hostname and addr data */
+    const char   *uds_path;    /* Unix domain socket path */
     const char   *hostname;
     apr_sockaddr_t *addr;      /* Preparsed remote address info */
     apr_pool_t   *scpool;      /* Subpool used for socket and connection data */

modules/proxy/proxy_util.c

@@ -31,6 +31,11 @@
 #define apr_socket_create apr_socket_create_ex
 #endif
 
+#if APR_HAVE_SYS_UN_H
+#include <sys/un.h>
+#endif
+#include "apr_support.h"        /* for apr_wait_for_io_or_timeout() */
+
 APLOG_USE_MODULE(proxy);
 
 /*
@@ -2008,6 +2013,7 @@ PROXY_DECLARE(int) ap_proxy_acquire_connection(const char *proxy_function,
     (*conn)->worker = worker;
     (*conn)->close  = 0;
     (*conn)->inreslist = 0;
+    (*conn)->uds_path = NULL;
 
     return OK;
 }
@@ -2024,6 +2030,30 @@ PROXY_DECLARE(int) ap_proxy_release_connection(const char *proxy_function,
     return OK;
 }
 
+/*
+ * Decodes a '%' escaped string, and returns the number of characters
+ */
+static int decodeenc(char *x)
+{
+    int i, j, ch;
+
+    if (x[0] == '\0') {
+        /* special case for no characters */
+        return 0;
+    }
+    for (i = 0, j = 0; x[i] != '\0'; i++, j++) {
+        /* decode it if not already done */
+        ch = x[i];
+        if (ch == '%' && apr_isxdigit(x[i + 1]) && apr_isxdigit(x[i + 2])) {
+            ch = ap_proxy_hex2c(&x[i + 1]);
+            i += 2;
+        }
+        x[j] = ch;
+    }
+    x[j] = '\0';
+    return j;
+}
+
 PROXY_DECLARE(int)
 ap_proxy_determine_connection(apr_pool_t *p, request_rec *r,
                               proxy_server_conf *conf,
@@ -2118,11 +2148,18 @@ ap_proxy_determine_connection(apr_pool_t *p, request_rec *r,
             conn->port = uri->port;
         }
         socket_cleanup(conn);
+        if (strncmp(conn->hostname, "socket=", 7) == 0) {
+            char *uds_path = apr_pstrdup(conn->pool, conn->hostname + 7);
+            decodeenc(uds_path);
+            conn->uds_path = uds_path;
+        }
+        else {
             err = apr_sockaddr_info_get(&(conn->addr),
                                         conn->hostname, APR_UNSPEC,
                                         conn->port, 0,
                                         conn->pool);
         }
+    }
     else if (!worker->cp->addr) {
         if ((err = PROXY_THREAD_LOCK(worker)) != APR_SUCCESS) {
             ap_log_rerror(APLOG_MARK, APLOG_ERR, err, r, APLOGNO(00945) "lock");
@@ -2346,6 +2383,50 @@ static apr_status_t send_http_connect(proxy_conn_rec *backend,
 }
 
 
+/* lifted from mod_proxy_fdpass.c; tweaked addrlen in connect() call */
+static apr_status_t socket_connect_un(apr_socket_t *sock,
+                                      struct sockaddr_un *sa)
+{
+    apr_status_t rv;
+    apr_os_sock_t rawsock;
+    apr_interval_time_t t;
+
+    rv = apr_os_sock_get(&rawsock, sock);
+    if (rv != APR_SUCCESS) {
+        return rv;
+    }
+
+    rv = apr_socket_timeout_get(sock, &t);
+    if (rv != APR_SUCCESS) {
+        return rv;
+    }
+
+    do {
+        const socklen_t addrlen = APR_OFFSETOF(struct sockaddr_un, sun_path)
+                                  + strlen(sa->sun_path) + 1;
+        rv = connect(rawsock, (struct sockaddr*)sa, addrlen);
+    } while (rv == -1 && errno == EINTR);
+
+    if ((rv == -1) && (errno == EINPROGRESS || errno == EALREADY)
+        && (t > 0)) {
+#if APR_MAJOR_VERSION < 2
+        rv = apr_wait_for_io_or_timeout(NULL, sock, 0);
+#else
+        rv = apr_socket_wait(sock, APR_WAIT_WRITE);
+#endif
+
+        if (rv != APR_SUCCESS) {
+            return rv;
+        }
+    }
+
+    if (rv == -1 && errno != EISCONN) {
+        return errno;
+    }
+
+    return APR_SUCCESS;
+}
+
 PROXY_DECLARE(int) ap_proxy_connect_backend(const char *proxy_function,
                                             proxy_conn_rec *conn,
                                             proxy_worker *worker,
@@ -2370,13 +2451,46 @@ PROXY_DECLARE(int) ap_proxy_connect_backend(const char *proxy_function,
                          proxy_function);
         }
     }
-    while (backend_addr && !connected) {
+    while ((backend_addr || conn->uds_path) && !connected) {
+        if (conn->uds_path) {
+            struct sockaddr_un sa;
+
+            rv = apr_socket_create(&newsock, AF_UNIX, SOCK_STREAM, 0,
+                                   conn->scpool);
+            if (rv != APR_SUCCESS) {
+                loglevel = APLOG_ERR;
+                ap_log_error(APLOG_MARK, loglevel, rv, s, APLOGNO()
+                             "%s: error creating Unix domain socket for "
+                             "target %s",
+                             proxy_function,
+                             worker->s->hostname);
+                break;
+            }
+            conn->connection = NULL;
+
+            sa.sun_family = AF_UNIX;
+            apr_cpystrn(sa.sun_path, conn->uds_path, sizeof(sa.sun_path));
+
+            rv = socket_connect_un(newsock, &sa);
+            if (rv != APR_SUCCESS) {
+                apr_socket_close(newsock);
+                ap_log_error(APLOG_MARK, APLOG_ERR, rv, s, APLOGNO()
+                             "%s: attempt to connect to Unix domain socket "
+                             "%s (%s) failed",
+                             proxy_function,
+                             conn->uds_path,
+                             worker->s->hostname);
+                break;
+            }
+        }
+        else {
             if ((rv = apr_socket_create(&newsock, backend_addr->family,
                                         SOCK_STREAM, APR_PROTO_TCP,
                                         conn->scpool)) != APR_SUCCESS) {
                 loglevel = backend_addr->next ? APLOG_DEBUG : APLOG_ERR;
                 ap_log_error(APLOG_MARK, loglevel, rv, s, APLOGNO(00952)
-                         "%s: error creating fam %d socket for target %s",
+                             "%s: error creating fam %d socket for "
+                             "target %s",
                              proxy_function,
                              backend_addr->family,
                              worker->s->hostname);
@@ -2458,6 +2572,7 @@ PROXY_DECLARE(int) ap_proxy_connect_backend(const char *proxy_function,
                 backend_addr = backend_addr->next;
                 continue;
             }
+        }
 
         /* Set a timeout on the socket */
         if (worker->s->timeout_set) {
@@ -2472,7 +2587,7 @@ PROXY_DECLARE(int) ap_proxy_connect_backend(const char *proxy_function,
 
         conn->sock = newsock;
 
-        if (conn->forward) {
+        if (!conn->uds_path && conn->forward) {
             forward_info *forward = (forward_info *)conn->forward;
             /*
              * For HTTP CONNECT we need to prepend CONNECT request before