diff --git a/socket.c b/socket.c index 993431df..e642082e 100644 --- a/socket.c +++ b/socket.c @@ -245,6 +245,18 @@ int open_socket_out_wrapped (char *host, /** * Open a socket of the specified type, port and address for incoming data * + * Try to be better about handling the results of getaddrinfo(): when + * opening an inbound socket, we might get several address results, + * e.g. for the machine's ipv4 and ipv6 name. + * + * If binding a wildcard, then any one of them should do. If an address + * was specified but it's insufficiently specific then that's not our + * fault. + * + * However, some of the advertized addresses may not work because e.g. we + * don't have IPv6 support in the kernel. In that case go on and try all + * addresses until one succeeds. + * * @param bind_address Local address to bind, or NULL to allow it to * default. **/ @@ -253,7 +265,7 @@ static int open_socket_in(int type, int port, const char *bind_address, { int one=1; int s; - struct addrinfo hints, *res; + struct addrinfo hints, *res, *resp; char portbuf[10]; int error; @@ -268,20 +280,32 @@ static int open_socket_in(int type, int port, const char *bind_address, bind_address, gai_strerror(error)); return -1; } - if (res->ai_next) { - rprintf(FERROR, RSYNC_NAME ": getaddrinfo: bind address %s: " - "resolved to multiple hosts\n", - bind_address); - freeaddrinfo(res); - return -1; - } + /* XXX: Do we need to care about getting multiple results + * back? I think probably not; if the user passed + * bind_address == NULL and we set AI_PASSIVE then we ought to + * get a wildcard result. */ - s = socket(res->ai_family, res->ai_socktype, res->ai_protocol); - if (s < 0) { - rprintf(FERROR, RSYNC_NAME ": open socket in failed: %s\n", - strerror(errno)); - freeaddrinfo(res); - return -1; + resp = res; + while (1) { + s = socket(resp->ai_family, resp->ai_socktype, resp->ai_protocol); + + if (s >= 0) { + break; /* got a socket */ + } else if ((resp = resp->ai_next)) { + switch (errno) { + case EPROTONOSUPPORT: + case EAFNOSUPPORT: + case EPFNOSUPPORT: + /* See if there's another address that will work... */ + continue; + } + } + + rprintf(FERROR, RSYNC_NAME ": open inbound socket" + "(dom=%d, type=%d, proto=%d) failed: %s\n", + resp->ai_family, resp->ai_socktype, resp->ai_protocol, + strerror(errno)); + goto fail; } setsockopt(s,SOL_SOCKET,SO_REUSEADDR,(char *)&one,sizeof(one)); @@ -289,12 +313,15 @@ static int open_socket_in(int type, int port, const char *bind_address, /* now we've got a socket - we need to bind it */ if (bind(s, res->ai_addr, res->ai_addrlen) < 0) { rprintf(FERROR, RSYNC_NAME ": bind failed on port %d\n", port); - freeaddrinfo(res); - close(s); - return -1; + close(s); + goto fail; } return s; + +fail: + freeaddrinfo(res); + return -1; }