X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=net.c;h=601396477c66715e21bc222d69c0d7e0b1aa9f92;hp=076600fc45f2952212835339ac4e991ee0e5edc6;hb=3e3c069366dbb2bf8f157ad0a406bda67dd51783;hpb=7a0852896a75d852dbd2ac848ec5c0be3b5dea71 diff --git a/net.c b/net.c index 076600fc..60139647 100644 --- a/net.c +++ b/net.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 2005-2007 Andre Noll + * Copyright (C) 2005-2008 Andre Noll * * Licensed under the GPL v2. For licencing details see COPYING. */ @@ -117,38 +117,42 @@ static const char *layer4_name(const unsigned l4type) /** * Resolve IPv4/IPv6 address and create a ready-to-use active or passive socket. * - * @param l3type The layer-3 type (\p AF_INET, \p AF_INET6, \p AF_UNSPEC) - * @param l4type The layer-4 type (\p IPPROTO_xxx). - * @param passive Whether this is a passive (1) or active (0) socket/ - * @param host Remote or local hostname or IPv/6 address string. - * @param port_number Decimal port number. - * - * This creates a ready-made IPv4/v6 socket structure after looking up the necessary - * parameters. The interpretation of \a host depends on the value of \a passive: - * - on a passive socket host is interpreted as an interface IPv4/6 address - * (can be left NULL); - * - on an active socket, \a host is the peer DNS name or IPv4/6 address to connect to; - * - \a port_number is in either case the numeric port number (not service string). - * Furthermore, bind(2) is called on passive sockets, and connect(2) on active sockets. - * The algorithm tries all possible address combinations until it succeeds. - * - * \return This function returns 1 on success and \a -E_ADDRESS_LOOKUP when no matching - * connection could be set up (with details in the error log). - * - * \sa ipv6(7), getaddrinfo(3), bind(2), connect(2) + * \param l3type The layer-3 type (\p AF_INET, \p AF_INET6, \p AF_UNSPEC). + * \param l4type The layer-4 type (\p IPPROTO_xxx). + * \param passive Whether this is a passive (1) or active (0) socket. + * \param host Remote or local hostname or IPv/6 address string. + * \param port_number Decimal port number. + * + * This creates a ready-made IPv4/v6 socket structure after looking up the + * necessary parameters. The interpretation of \a host depends on the value of + * \a passive: + * - on a passive socket host is interpreted as an interface IPv4/6 address + * (can be left NULL); + * - on an active socket, \a host is the peer DNS name or IPv4/6 address + * to connect to; + * - \a port_number is in either case the numeric port number (not service + * string). + * + * Furthermore, bind(2) is called on passive sockets, and connect(2) on active + * sockets. The algorithm tries all possible address combinations until it + * succeeds. + * + * \return This function returns 1 on success and \a -E_ADDRESS_LOOKUP when no + * matching connection could be set up (with details in the error log). + * + * \sa ipv6(7), getaddrinfo(3), bind(2), connect(2). */ int makesock(unsigned l3type, unsigned l4type, int passive, - const char *host, unsigned short port_number) + const char *host, unsigned short port_number) { struct addrinfo *local = NULL, *src, *remote = NULL, *dst, hints; - char *port = make_message("%u", port_number); int rc, on = 1, sockfd = -1, socktype = sock_type(l4type); + char port[6]; /* port number has at most 5 digits */ - /* - * Set up address hint structure - */ + sprintf(port, "%u", port_number); + /* Set up address hint structure */ memset(&hints, 0, sizeof(hints)); hints.ai_family = l3type; /* getaddrinfo does not really work well with SOCK_DCCP */ @@ -164,35 +168,35 @@ int makesock(unsigned l3type, unsigned l4type, int passive, if (passive && host == NULL) hints.ai_flags |= AI_PASSIVE; - /* - * Obtain local/remote address information - */ + /* Obtain local/remote address information */ if ((rc = getaddrinfo(host, port, &hints, passive ? &local : &remote))) { PARA_ERROR_LOG("can not resolve %s address %s#%s: %s.\n", layer4_name(l4type), - host? : (passive? "[loopback]" : "[localhost]"), + host? host : (passive? "[loopback]" : "[localhost]"), port, gai_strerror(rc)); return -E_ADDRESS_LOOKUP; } - /* - * Iterate over all src/dst combination, exhausting dst first - */ + /* Iterate over all src/dst combination, exhausting dst first */ for (src = local, dst = remote; src != NULL || dst != NULL; /* no op */ ) { if (src && dst && src->ai_family == AF_INET - && dst->ai_family == AF_INET6) /* v4 -> v6 is not possible */ - goto get_next_dst; + && dst->ai_family == AF_INET6) + goto get_next_dst; /* v4 -> v6 is not possible */ - sockfd = socket(src ? src->ai_family : dst->ai_family, socktype, l4type); + sockfd = socket(src ? src->ai_family : dst->ai_family, + socktype, l4type); if (sockfd < 0) goto get_next_dst; /* - * Set those options that need to be set before establishing the connection + * Set those options that need to be set before establishing + * the connection. Reuse the address on passive (listening) + * sockets to avoid failure on restart. */ - /* Reuse the address on passive (listening) sockets to avoid failure on restart */ - if (passive && setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1) { - PARA_ERROR_LOG("can not set SO_REUSEADDR: %s\n", strerror(errno)); + if (passive && setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, + &on, sizeof(on)) == -1) { + PARA_ERROR_LOG("can not set SO_REUSEADDR: %s\n", + strerror(errno)); return -ERRNO_TO_PARA_ERROR(errno); } @@ -201,19 +205,19 @@ int makesock(unsigned l3type, unsigned l4type, int passive, close(sockfd); goto get_next_src; } - if (!dst) - break; /* bind-only completed successfully */ + if (!dst) /* bind-only completed successfully */ + break; } if (dst && connect(sockfd, dst->ai_addr, dst->ai_addrlen) == 0) - break; /* connection completed successfully */ + break; /* connection completed successfully */ close(sockfd); get_next_dst: if (dst && (dst = dst->ai_next)) continue; get_next_src: - if (src && (src = src->ai_next)) - dst = remote; /* restart inner loop */ + if (src && (src = src->ai_next)) /* restart inner loop */ + dst = remote; } if (local) freeaddrinfo(local); @@ -221,8 +225,9 @@ get_next_src: freeaddrinfo(remote); if (src == NULL && dst == NULL) { - PARA_ERROR_LOG("can not create %s socket %s#%s.\n", layer4_name(l4type), - host? : (passive? "[loopback]" : "[localhost]"), port); + PARA_ERROR_LOG("can not create %s socket %s#%s.\n", + layer4_name(l4type), host? host : (passive? + "[loopback]" : "[localhost]"), port); return -ERRNO_TO_PARA_ERROR(errno); } return sockfd; @@ -230,11 +235,14 @@ get_next_src: /** * Create a passive / listening socket. - * \param l3type The network-layer type (\p AF_xxx) - * \param l4type The transport-layer type (\p IPPROTO_xxx). - * \param port The decimal port number to listen on. * - * \return Positive integer (socket descriptor) on success, negative value otherwise. + * \param l3type The network-layer type (\p AF_xxx). + * \param l4type The transport-layer type (\p IPPROTO_xxx). + * \param port The decimal port number to listen on. + * + * \return Positive integer (socket descriptor) on success, negative value + * otherwise. + * * \sa makesock(), ip(7), ipv6(7), bind(2), listen(2). */ int para_listen(unsigned l3type, unsigned l4type, unsigned short port) @@ -248,59 +256,64 @@ int para_listen(unsigned l3type, unsigned l4type, unsigned short port) return -ERRNO_TO_PARA_ERROR(errno); } PARA_INFO_LOG("listening on %s port %u, fd %d\n", - layer4_name(l4type), port, fd); + layer4_name(l4type), port, fd); } return fd; } /** * Print numeric host and port number (beware - uses static char). - * \param sa The IPv4/IPv6 socket address to use. - * \param len The length of \p sa. * - * \sa getnameinfo(3) + * \param sa The IPv4/IPv6 socket address to use. + * \param len The length of \p sa. + * + * \sa getnameinfo(3). */ -char *host_and_port(struct sockaddr *sa, socklen_t len) +static char *host_and_port(struct sockaddr *sa, socklen_t len) { - static char output[NI_MAXHOST + NI_MAXSERV + 2]; - char hbuf[NI_MAXHOST], - sbuf[NI_MAXSERV]; - int ret; + static char output[NI_MAXHOST + NI_MAXSERV + 2]; + char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV]; + int ret; ret = getnameinfo(sa, len, hbuf, sizeof(hbuf), sbuf, sizeof(sbuf), - NI_NUMERICHOST | NI_NUMERICSERV); - if (ret) { - PARA_WARNING_LOG("hostname lookup error (%s).\n", gai_strerror(ret)); + NI_NUMERICHOST | NI_NUMERICSERV); + if (ret) { + PARA_WARNING_LOG("hostname lookup error (%s).\n", + gai_strerror(ret)); sprintf(output, "(unknown)"); - } else { + } else sprintf(output, "%s#%s", hbuf, sbuf); - } return output; } /** * Look up the local or remote side of a connected socket structure. - * \param fd The socket descriptor of the connected socket. - * \param getname Either \fn getsockname() for local, or \fn getpeername() for remote side. * - * \return A static character string identifying hostname and port of the chosen side - * \sa getsockname(2), getpeername(2) + * \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. + * + * \sa getsockname(2), getpeername(2). */ -static char *__get_sock_name(int fd, int (*getname)(int, struct sockaddr*, socklen_t *)) +static char *__get_sock_name(int fd, int (*getname)(int, struct sockaddr*, + socklen_t *)) { - struct sockaddr_storage ss; - socklen_t sslen = sizeof(ss); + struct sockaddr_storage ss; + socklen_t sslen = sizeof(ss); if (getname(fd, (struct sockaddr *)&ss, &sslen) < 0) { static char *dont_know = "(don't know)"; - PARA_ERROR_LOG("can not determine address from fd %d: %s\n", fd, strerror(errno)); + PARA_ERROR_LOG("can not determine address from fd %d: %s\n", + fd, strerror(errno)); return dont_know; } - return host_and_port((struct sockaddr *)&ss, sslen); } -char *local_name(int sockfd) +char *local_name(int sockfd) { return __get_sock_name(sockfd, getsockname); } @@ -310,6 +323,28 @@ char *remote_name(int sockfd) return __get_sock_name(sockfd, getpeername); } +/** + * Extract IPv4 or IPv6-mapped-IPv4 address from sockaddr_storage. + * \param ss Container of IPv4/6 address + * \return Extracted IPv4 address (different from 0) or 0 if unsuccessful. + * + * \sa RFC 3493 + */ +struct in_addr extract_v4_addr(const struct sockaddr_storage *ss) +{ + struct in_addr ia = {.s_addr = 0}; + + if (ss->ss_family == AF_INET) + ia.s_addr = ((struct sockaddr_in *)ss)->sin_addr.s_addr; + if (ss->ss_family == AF_INET6) { + const struct in6_addr v6_addr = ((struct sockaddr_in6 *)ss)->sin6_addr; + + if (IN6_IS_ADDR_V4MAPPED(&v6_addr)) + memcpy(&ia.s_addr, &(v6_addr.s6_addr[12]), 4); + } + return ia; +} + /* * Send out a buffer, resend on short writes. * @@ -327,7 +362,7 @@ static int sendall(int fd, const char *buf, size_t *len) assert(total); *len = 0; while (*len < total) { - int ret = send(fd, buf + *len, total - *len, 0); + int ret = write(fd, buf + *len, total - *len); if (ret == -1) return -ERRNO_TO_PARA_ERROR(errno); *len += ret; @@ -354,7 +389,7 @@ int send_bin_buffer(int fd, const char *buf, size_t len) crypt_function *cf = NULL; if (!len) - PARA_CRIT_LOG("%s", "len == 0\n"); + PARA_CRIT_LOG("len == 0\n"); if (fd + 1 <= cda_size) cf = crypt_data_array[fd].send; if (cf) { @@ -493,10 +528,10 @@ int para_accept(int fd, void *addr, socklen_t size) } /** - * prepare a structure for \p AF_UNIX socket addresses + * Prepare a structure for \p AF_UNIX socket addresses. * - * \param u pointer to the struct to be prepared - * \param name the socket pathname + * \param u Pointer to the struct to be prepared. + * \param name The socket pathname. * * This just copies \a name to the sun_path component of \a u. * @@ -565,7 +600,7 @@ err: * * \return The file descriptor, on success, negative on errors. * - * \sa create_local_socket(), unix(7), connect(2) + * \sa create_local_socket(), unix(7), connect(2). */ int create_remote_socket(const char *name) { @@ -599,16 +634,15 @@ int recv_cred_buffer(int fd, char *buf, size_t size) } #else /* HAVE_UCRED */ /** - * send NULL terminated buffer and Unix credentials of the current process + * Send \p NULL-terminated buffer and Unix credentials of the current process. * - * \param sock the socket file descriptor - * \param buf the buffer to be sent + * \param sock The socket file descriptor. + * \param buf The buffer to be sent. * * \return On success, this call returns the number of characters sent. On * error, \p -E_SENDMSG is returned. * - * \sa okir's Black Hats Manual - * \sa sendmsg(2) + * \sa sendmsg(2), okir's Black Hats Manual. */ ssize_t send_cred_buffer(int sock, char *buf) { @@ -653,16 +687,15 @@ static void dispose_fds(int *fds, unsigned num) } /** - * receive a buffer and the Unix credentials of the sending process + * 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 socket file descriptor. + * \param buf the buffer to store the message. + * \param size the size of \a buffer. * * \return negative on errors, the user id on success. * - * \sa okir's Black Hats Manual - * \sa recvmsg(2) + * \sa recvmsg(2), okir's Black Hats Manual. */ int recv_cred_buffer(int fd, char *buf, size_t size) { @@ -706,11 +739,11 @@ int recv_cred_buffer(int fd, char *buf, size_t size) #endif /* HAVE_UCRED */ /** - * receive a buffer and check for a pattern + * Receive a buffer and check for a pattern. * - * \param fd the file descriptor to receive from - * \param pattern the expected pattern - * \param bufsize the size of the internal buffer + * \param fd The file descriptor to receive from. + * \param pattern The expected pattern. + * \param bufsize The size of the internal buffer. * * \return Positive if \a pattern was received, negative otherwise. * @@ -719,8 +752,7 @@ int recv_cred_buffer(int fd, char *buf, size_t size) * If at least \p strlen(\a pattern) bytes were received, the beginning of * the received buffer is compared with \a pattern, ignoring case. * - * \sa recv_buffer() - * \sa strncasecmp(3) + * \sa recv_buffer(), \sa strncasecmp(3). */ int recv_pattern(int fd, const char *pattern, size_t bufsize) { @@ -735,7 +767,8 @@ int recv_pattern(int fd, const char *pattern, size_t bufsize) ret = 1; out: if (ret < 0) { - PARA_NOTICE_LOG("n = %d, did not receive pattern '%s'\n", n, pattern); + PARA_NOTICE_LOG("n = %d, did not receive pattern '%s'\n", n, + pattern); if (n > 0) PARA_NOTICE_LOG("recvd: %s\n", buf); }