X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=net.c;h=a58d84ef1c6345dcef41ca5b3ba76d3ed602cb7b;hp=c11f67c4bac3f7f316daa317ae71ed8ebe6f10a9;hb=b1206644af64376f11877f14fa9f9dd3c30f8e4b;hpb=bfdd36f2879b8dee1f6d3330bc49fbb5644d3caf diff --git a/net.c b/net.c index c11f67c4..a58d84ef 100644 --- a/net.c +++ b/net.c @@ -1,16 +1,12 @@ /* - * Copyright (C) 2005-2014 Andre Noll + * Copyright (C) 2005 Andre Noll * * Licensed under the GPL v2. For licencing details see COPYING. */ /** \file net.c Networking-related helper functions. */ -/* - * Since glibc 2.8, the _GNU_SOURCE feature test macro must be defined in order - * to obtain the definition of the ucred structure. - */ -#define _GNU_SOURCE +#include "para.h" #include #include @@ -32,7 +28,6 @@ #include -#include "para.h" #include "error.h" #include "net.h" #include "string.h" @@ -48,8 +43,8 @@ * \param netmask Value of the netmask part in \a cidr or the * default of 32 if not specified. * - * \return Pointer to \a addr if succesful, NULL on error. - * \sa RFC 4632 + * \return Pointer to \a addr if successful, NULL on error. + * \sa RFC 4632. */ char *parse_cidr(const char *cidr, char *addr, ssize_t addrlen, @@ -109,7 +104,7 @@ static bool is_v4_dot_quad(const char *address) * \param host The host string to check. * \return True if \a host passes the syntax checks. * - * \sa RFC 3986, 3.2.2; RFC 1123, 2.1; RFC 1034, 3.5 + * \sa RFC 3986, 3.2.2; RFC 1123, 2.1; RFC 1034, 3.5. */ static bool host_string_ok(const char *host) { @@ -151,7 +146,7 @@ static bool host_string_ok(const char *host) * \a host and \a port are undefined. If no port number was present in \a url, * \a port is set to -1. * - * \sa RFC 3986, 3.2.2/3.2.3 + * \sa RFC 3986, 3.2.2/3.2.3. */ char *parse_url(const char *url, char *host, ssize_t hostlen, @@ -180,8 +175,7 @@ char *parse_url(const char *url, } if (*o == ':') - if (para_atoi32(++o, port) < 0 || - *port < 0 || *port > 0xffff) + if (para_atoi32(++o, port) < 0 || *port < 0 || *port > 0xffff) goto failed; if (host_string_ok(host)) return host; @@ -192,11 +186,12 @@ failed: /** * Stringify port number, resolve into service name where defined. + * * \param port 2-byte port number, in host-byte-order. * \param transport Transport protocol name (e.g. "udp", "tcp"), or NULL. * \return Pointer to static result buffer. * - * \sa getservent(3), services(5), nsswitch.conf(5) + * \sa getservent(3), services(5), nsswitch.conf(5). */ const char *stringify_port(int port, const char *transport) { @@ -208,7 +203,7 @@ const char *stringify_port(int port, const char *transport) struct servent *se = getservbyport(htons(port), transport); if (se == NULL) - snprintf(service, sizeof(service), "%u", port); + snprintf(service, sizeof(service), "%d", port); else snprintf(service, sizeof(service), "%s", se->s_name); } @@ -220,7 +215,7 @@ const char *stringify_port(int port, const char *transport) * * \param l4type The symbolic name of the transport-layer protocol. * - * \sa ip(7), socket(2) + * \sa ip(7), socket(2). */ static inline int sock_type(const unsigned l4type) { @@ -252,7 +247,7 @@ static const char *layer4_name(const unsigned l4type) * directly after makesock(). The 'pre_conn_opt' structure is for internal use * only and should not be visible elsewhere. * - * \sa setsockopt(2), makesock() + * \sa setsockopt(2), \ref makesock(). */ struct pre_conn_opt { int sock_level; /**< Second argument to setsockopt() */ @@ -293,7 +288,7 @@ struct flowopts *flowopt_new(void) * \param val The value to set \a opt to. * \param len Length of \a val. * - * \sa setsockopt(2) + * \sa setsockopt(2). */ void flowopt_add(struct flowopts *fo, int lev, int opt, const char *name, const void *val, int len) @@ -381,7 +376,7 @@ int lookup_address(unsigned l4type, bool passive, const char *host, struct addrinfo *addr = NULL, hints; *result = NULL; - sprintf(port, "%u", port_number & 0xffff); + sprintf(port, "%d", port_number & 0xffff); /* Set up address hint structure */ memset(&hints, 0, sizeof(hints)); hints.ai_family = AF_UNSPEC; @@ -510,7 +505,7 @@ int makesock(unsigned l4type, bool passive, const char *host, uint16_t port_numb * \return Positive integer (socket descriptor) on success, negative value * otherwise. * - * \sa makesock(), ip(7), ipv6(7), bind(2), listen(2). + * \sa \ref makesock(), ip(7), ipv6(7), bind(2), listen(2). */ int para_listen(unsigned l4type, uint16_t port, struct flowopts *fo) { @@ -556,7 +551,7 @@ static bool SS_IS_ADDR_V4MAPPED(const struct sockaddr_storage *ss) * \param ss Container of IPv4/6 address. * \return Pointer to normalized address (may be static storage). * - * \sa RFC 3493 + * \sa RFC 3493. */ static const struct sockaddr * normalize_ip_address(const struct sockaddr_storage *ss) @@ -601,14 +596,14 @@ static inline int estimated_header_overhead(const int af_type) * * \param sockfd The socket file descriptor. * - * The socket must be connected. See RFC 1122, 3.3.3. If the protocol familiy + * The socket must be connected. See RFC 1122, 3.3.3. If the protocol family * could not be determined, \p AF_INET is assumed. * * \return The maximum message size of the address family type. */ int generic_max_transport_msg_size(int sockfd) { - struct sockaddr_storage ss; + struct sockaddr_storage ss = {.ss_family = 0}; socklen_t sslen = sizeof(ss); int af_type = AF_INET; @@ -622,28 +617,26 @@ int generic_max_transport_msg_size(int sockfd) } /** - * Look up the local or remote side of a connected socket structure. + * Look up the remote side of a connected socket structure. * * \param fd The socket descriptor of the connected socket. - * \param getname Either \p getsockname() for local, or \p getpeername() for - * remote side. * * \return A static character string identifying hostname and port of the * chosen side in numeric host:port format. * - * \sa getsockname(2), getpeername(2), parse_url(), getnameinfo(3), + * \sa getsockname(2), getpeername(2), \ref parse_url(), getnameinfo(3), * services(5), nsswitch.conf(5). */ -static char *__get_sock_name(int fd, typeof(getsockname) getname) +char *remote_name(int fd) { - struct sockaddr_storage ss; + struct sockaddr_storage ss = {.ss_family = 0}; const struct sockaddr *sa; socklen_t sslen = sizeof(ss); char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV]; static char output[sizeof(hbuf) + sizeof(sbuf) + 4]; int ret; - if (getname(fd, (struct sockaddr *)&ss, &sslen) < 0) { + if (getpeername(fd, (struct sockaddr *)&ss, &sslen) < 0) { PARA_ERROR_LOG("can not determine address from fd %d: %s\n", fd, strerror(errno)); snprintf(output, sizeof(output), "(unknown)"); @@ -663,36 +656,6 @@ static char *__get_sock_name(int fd, typeof(getsockname) getname) return output; } -/** - * Look up the local side of a connected socket structure. - * - * \param sockfd The file descriptor of the socket. - * - * \return A pointer to a static buffer containing hostname an port. This - * buffer must not be freed by the caller. - * - * \sa remote_name(). - */ -char *local_name(int sockfd) -{ - return __get_sock_name(sockfd, getsockname); -} - -/** - * Look up the remote side of a connected socket structure. - * - * \param sockfd The file descriptor of the socket. - * - * \return Analogous to the return value of \ref local_name() but for the - * remote side. - * - * \sa local_name(). - */ -char *remote_name(int sockfd) -{ - return __get_sock_name(sockfd, getpeername); -} - /** * Extract IPv4 or IPv6-mapped-IPv4 address from sockaddr_storage. * @@ -772,7 +735,7 @@ __must_check int recv_bin_buffer(int fd, char *buf, size_t size) * * \return The return value of the underlying call to \a recv_bin_buffer(). * - * \sa recv_bin_buffer() + * \sa \ref recv_bin_buffer() */ int recv_buffer(int fd, char *buf, size_t size) { @@ -855,63 +818,85 @@ int dccp_available_ccids(uint8_t **ccid_array) return nccids; } -/** - * Prepare a structure for \p AF_UNIX socket addresses. - * - * \param u Pointer to the struct to be prepared. - * \param name The socket pathname. +/* + * Prepare a structure for AF_UNIX socket addresses. * - * This just copies \a name to the sun_path component of \a u. + * This just copies name to the sun_path component of u, prepending a zero byte + * if abstract sockets are supported. * - * \return Positive on success, \p -E_NAME_TOO_LONG if \a name is longer - * than \p UNIX_PATH_MAX. + * The first call to this function tries to bind a socket to the abstract name + * space. The result of this test is stored in a static variable. Subsequent + * calls read this variable and create abstract sockets on systems that support + * them. */ static int init_unix_addr(struct sockaddr_un *u, const char *name) { - if (strlen(name) >= UNIX_PATH_MAX) + static int use_abstract; + + if (strlen(name) + 1 >= UNIX_PATH_MAX) return -E_NAME_TOO_LONG; memset(u->sun_path, 0, UNIX_PATH_MAX); u->sun_family = PF_UNIX; - strcpy(u->sun_path, name); + if (use_abstract == 0) { /* executed only once */ + int fd = socket(PF_UNIX, SOCK_STREAM, 0); + memcpy(u->sun_path, "\0x\0", 3); + if (bind(fd, (struct sockaddr *)u, sizeof(*u)) == 0) + use_abstract = 1; /* yes */ + else + use_abstract = -1; /* no */ + close(fd); + PARA_NOTICE_LOG("%susing abstract socket namespace\n", + use_abstract == 1? "" : "not "); + } + strcpy(u->sun_path + (use_abstract == 1? 1 : 0), name); return 1; } /** - * Prepare, create, and bind a socket for local communication. + * Create a socket for local communication and listen on it. * * \param name The socket pathname. - * \param unix_addr Pointer to the \p AF_UNIX socket structure. - * \param mode The desired mode of the socket. * - * This function creates a local socket for sequenced, reliable, - * two-way, connection-based byte streams. + * This function creates a passive local socket for sequenced, reliable, + * two-way, connection-based byte streams. The socket file descriptor is set to + * nonblocking mode and listen(2) is called to prepare the socket for + * accepting incoming connection requests. * - * \return The file descriptor, on success, negative on errors. + * \return The file descriptor on success, negative error code on failure. * - * \sa socket(2) - * \sa bind(2) - * \sa chmod(2) + * \sa socket(2), \sa bind(2), \sa chmod(2), listen(2), unix(7). */ -int create_local_socket(const char *name, struct sockaddr_un *unix_addr, - mode_t mode) +int create_local_socket(const char *name) { + struct sockaddr_un unix_addr; int fd, ret; - ret = init_unix_addr(unix_addr, name); + ret = init_unix_addr(&unix_addr, name); if (ret < 0) return ret; ret = socket(PF_UNIX, SOCK_STREAM, 0); if (ret < 0) return -ERRNO_TO_PARA_ERROR(errno); fd = ret; - ret = bind(fd, (struct sockaddr *) unix_addr, UNIX_PATH_MAX); + ret = mark_fd_nonblocking(fd); + if (ret < 0) + goto err; + ret = bind(fd, (struct sockaddr *)&unix_addr, sizeof(unix_addr)); if (ret < 0) { ret = -ERRNO_TO_PARA_ERROR(errno); goto err; } - ret = -E_CHMOD; - if (chmod(name, mode) < 0) + if (unix_addr.sun_path[0] != 0) { /* pathname socket */ + mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP + | S_IROTH | S_IWOTH; + ret = -E_CHMOD; + if (chmod(name, mode) < 0) + goto err; + } + if (listen(fd , 5) < 0) { + ret = -ERRNO_TO_PARA_ERROR(errno); goto err; + } return fd; err: close(fd); @@ -929,7 +914,7 @@ err: * \return The file descriptor of the connected socket on success, negative on * errors. * - * \sa create_local_socket(), unix(7), connect(2). + * \sa \ref create_local_socket(), unix(7), connect(2). */ int connect_local_socket(const char *name) { @@ -937,17 +922,15 @@ int connect_local_socket(const char *name) int fd, ret; PARA_DEBUG_LOG("connecting to %s\n", name); - ret = init_unix_addr(&unix_addr, name); - if (ret < 0) - return ret; fd = socket(PF_UNIX, SOCK_STREAM, 0); if (fd < 0) return -ERRNO_TO_PARA_ERROR(errno); - if (connect(fd, (struct sockaddr *)&unix_addr, sizeof(unix_addr)) == -1) { - ret = -ERRNO_TO_PARA_ERROR(errno); + ret = init_unix_addr(&unix_addr, name); + if (ret < 0) goto err; - } - return fd; + if (connect(fd, (struct sockaddr *)&unix_addr, sizeof(unix_addr)) != -1) + return fd; + ret = -ERRNO_TO_PARA_ERROR(errno); err: close(fd); return ret; @@ -963,16 +946,17 @@ int recv_cred_buffer(int fd, char *buf, size_t size) return recv_buffer(fd, buf, size) > 0? 1 : -E_RECVMSG; } #else /* HAVE_UCRED */ + /** - * Send \p NULL-terminated buffer and Unix credentials of the current process. + * Send a buffer and the credentials of the current process to a socket. * - * \param sock The socket file descriptor. - * \param buf The buffer to be sent. + * \param sock The file descriptor of the sending socket. + * \param buf The zero-terminated buffer to send. * - * \return On success, this call returns the number of characters sent. On - * error, \p -E_SENDMSG is returned. + * \return On success, this call returns the number of bytes sent. On errors, + * \p -E_SENDMSG is returned. * - * \sa sendmsg(2), okir's Black Hats Manual. + * \sa \ref recv_cred_buffer, sendmsg(2), socket(7), unix(7). */ ssize_t send_cred_buffer(int sock, char *buf) { @@ -985,7 +969,7 @@ ssize_t send_cred_buffer(int sock, char *buf) /* Response data */ iov.iov_base = buf; - iov.iov_len = strlen(buf); + iov.iov_len = strlen(buf); c.pid = getpid(); c.uid = getuid(); c.gid = getgid(); @@ -1003,7 +987,7 @@ ssize_t send_cred_buffer(int sock, char *buf) *(struct ucred *)CMSG_DATA(cmsg) = c; msg.msg_controllen = cmsg->cmsg_len; ret = sendmsg(sock, &msg, 0); - if (ret < 0) + if (ret < 0) ret = -E_SENDMSG; return ret; } @@ -1019,17 +1003,17 @@ static void dispose_fds(int *fds, unsigned num) /** * Receive a buffer and the Unix credentials of the sending process. * - * \param fd the socket file descriptor. - * \param buf the buffer to store the message. - * \param size the size of \a buffer. + * \param fd The file descriptor of the receiving socket. + * \param buf The buffer to store the received message. + * \param size The length of \a buf in bytes. * - * \return negative on errors, the user id on success. + * \return Negative on errors, the user id of the sending process on success. * - * \sa recvmsg(2), okir's Black Hats Manual. + * \sa \ref send_cred_buffer and the references given there. */ int recv_cred_buffer(int fd, char *buf, size_t size) { - char control[255]; + char control[255] __a_aligned(8); struct msghdr msg; struct cmsghdr *cmsg; struct iovec iov; @@ -1058,7 +1042,7 @@ int recv_cred_buffer(int fd, char *buf, size_t size) } else if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS) { - dispose_fds((int *) CMSG_DATA(cmsg), + dispose_fds((int *)CMSG_DATA(cmsg), (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int)); }