From: Rudi Ihle Date: Thu, 14 Jun 2012 07:21:43 +0000 (+0200) Subject: Modified mechanism to assign privileged ports and enable it for Windows as well X-Git-Tag: upstream/1.9.6^2~242^2~10 X-Git-Url: https://git.piment-noir.org/?a=commitdiff_plain;h=2521374f70d1a666c0e8d59eec926ef254ffc186;p=deb_libnfs.git Modified mechanism to assign privileged ports and enable it for Windows as well --- diff --git a/lib/socket.c b/lib/socket.c index 71bb817..c64bf2e 100644 --- a/lib/socket.c +++ b/lib/socket.c @@ -362,8 +362,6 @@ static int rpc_connect_sockaddr_async(struct rpc_context *rpc, struct sockaddr_s return -1; } - -#if !defined(WIN32) /* Some systems allow you to set capabilities on an executable * to allow the file to be executed with privilege to bind to * privileged system ports, even if the user is not root. @@ -378,32 +376,38 @@ static int rpc_connect_sockaddr_async(struct rpc_context *rpc, struct sockaddr_s * On linux, use * sudo setcap 'cap_net_bind_service=+ep' /path/executable * to make the executable able to bind to a system port. + * + * On Windows, there is no concept of privileged ports. Thus + * binding will usually succeed. */ - if (1) { - static int port = 200; - int i; - int one = 1; - - setsockopt(rpc->fd, SOL_SOCKET, SO_REUSEADDR, (char *)&one, sizeof(one)); - - for (i = 0; i < 500; i++) { - struct sockaddr_in sin; - - if(++port > 700) port = 200; - - memset(&sin, 0, sizeof(sin)); - sin.sin_port = htons(port); - sin.sin_family = AF_INET; - sin.sin_addr.s_addr = 0; - - if (bind(rpc->fd, (struct sockaddr *)&sin, sizeof(struct sockaddr_in)) != 0 && errno != EACCES) { - /* we didnt get EACCES, so try again */ - continue; + { + struct sockaddr_in sin; + static int portOfs = 0; + const int firstPort = 512; /* >= 512 according to Sun docs */ + const int portCount = IPPORT_RESERVED - firstPort; + int startOfs = portOfs, port, rc; + + do { + rc = -1; + port = htons(firstPort + portOfs); + portOfs = (portOfs + 1) % portCount; + + /* skip well-known ports */ + if (!getservbyport(port, "tcp")) { + memset(&sin, 0, sizeof(sin)); + sin.sin_port = port; + sin.sin_family = AF_INET; + sin.sin_addr.s_addr = 0; + + rc = bind(rpc->fd, (struct sockaddr *)&sin, sizeof(struct sockaddr_in)); +#if !defined(WIN32) + /* we got EACCES, so don't try again */ + if (rc != 0 && errno == EACCES) + break; +#endif } - break; - } + } while (rc != 0 && portOfs != startOfs); } -#endif set_nonblocking(rpc->fd);