/*
- * Copyright (C) 2005-2006 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2005-2009 Andre Noll <maan@systemlinux.org>
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
+ * Licensed under the GPL v2. For licencing details see COPYING.
*/
-/** \file net.c networking-related helper functions */
+/** \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 <netdb.h>
+
+/* At least NetBSD needs these. */
+#ifndef AI_V4MAPPED
+#define AI_V4MAPPED 0
+#endif
+#ifndef AI_ALL
+#define AI_ALL 0
+#endif
+#ifndef AI_ADDRCONFIG
+#define AI_ADDRCONFIG 0
+#endif
+
+#include <dirent.h>
+#include <regex.h>
+#include <openssl/rc4.h>
#include "para.h"
+#include "error.h"
+#include "crypt.h"
#include "net.h"
#include "string.h"
-#include "error.h"
+#include "fd.h"
+
+/**
+ * Parse and validate IPv4 address/netmask string.
+ *
+ * \param cidr Address in CIDR notation
+ * \param addr Copy of the IPv4 address part of \a cidr
+ * \param addrlen Size of \a addr in bytes
+ * \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
+ */
+char *parse_cidr(const char *cidr,
+ char *addr, ssize_t addrlen,
+ int32_t *netmask)
+{
+ const char *o = cidr;
+ char *c = addr, *end = c + (addrlen - 1);
+
+ *netmask = 0x20;
+ if (cidr == NULL || addrlen < 1)
+ goto failed;
-/** \cond holds information about one encrypted connection */
-struct crypt_data {
- crypt_function *recv;
- crypt_function *send;
- void *private_data;
-};
-static unsigned cda_size = 0;
-static struct crypt_data *crypt_data_array;
-/** \endcond */
+ for (o = cidr; (*c = *o == '/'? '\0' : *o); c++, o++)
+ if (c == end)
+ goto failed;
+
+ if (*o == '/')
+ if (para_atoi32(++o, netmask) < 0 ||
+ *netmask < 0 || *netmask > 0x20)
+ goto failed;
+
+ if (is_valid_ipv4_address(addr))
+ return addr;
+failed:
+ *addr = '\0';
+ return NULL;
+}
/**
- * activate encryption for one file descriptor
+ * Match string as a candidate IPv4 address.
*
- * \param fd the file descriptor
- * \param recv_f the function used for decrypting received data
- * \param send_f the function used for encrypting before sending
- * \param private_data user data supplied by the caller
+ * \param address The string to match.
+ * \return True if \a address has "dot-quad" format.
*/
-void enable_crypt(int fd, crypt_function *recv_f, crypt_function *send_f,
- void *private_data)
+static bool is_v4_dot_quad(const char *address)
{
- if (fd + 1 > cda_size) {
- crypt_data_array = para_realloc(crypt_data_array,
- (fd + 1) * sizeof(struct crypt_data));
- memset(crypt_data_array + cda_size, 0,
- (fd + 1 - cda_size) * sizeof(struct crypt_data));
- cda_size = fd + 1;
- }
- crypt_data_array[fd].recv = recv_f;
- crypt_data_array[fd].send = send_f;
- crypt_data_array[fd].private_data = private_data;
- PARA_INFO_LOG("rc4 encryption activated for fd %d\n", fd);
+ bool result;
+ regex_t r;
+
+ assert(para_regcomp(&r, "^([0-9]+\\.){3}[0-9]+$",
+ REG_EXTENDED | REG_NOSUB) >= 0);
+ result = regexec(&r, address, 0, NULL, 0) == 0;
+ regfree(&r);
+ return result;
}
/**
- * deactivate encryption for a given fd
+ * Perform basic syntax checking on the host-part of an URL:
*
- * \param fd the file descriptor
+ * - Since ':' is invalid in IPv4 addresses and DNS names, the
+ * presence of ':' causes interpretation as IPv6 address;
+ * - next the first-match-wins algorithm from RFC 3986 is applied;
+ * - else the string is considered as DNS name, to be resolved later.
*
- * This must be called if and only if \p fd was activated via enable_crypt().
+ * \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
*/
-void disable_crypt(int fd)
+static bool host_string_ok(const char *host)
{
- if (cda_size < fd + 1)
- return;
- crypt_data_array[fd].recv = NULL;
- crypt_data_array[fd].send = NULL;
- crypt_data_array[fd].private_data = NULL;
+ if (host == NULL || *host == '\0')
+ return false;
+ if (strchr(host, ':') != NULL)
+ return is_valid_ipv6_address(host);
+ if (is_v4_dot_quad(host))
+ return is_valid_ipv4_address(host);
+ return true;
}
+/**
+ * Parse and validate URL string.
+ *
+ * The URL syntax is loosely based on RFC 3986, supporting one of
+ * - "["host"]"[:port] for native IPv6 addresses and
+ * - host[:port] for IPv4 hostnames and DNS names.
+ *
+ * Native IPv6 addresses must be enclosed in square brackets, since
+ * otherwise there is an ambiguity with the port separator `:'.
+ * The 'port' part is always considered to be a number; if absent,
+ * it is set to -1, to indicate that a default port is to be used.
+ *
+ * The following are valid examples:
+ * - 10.10.1.1
+ * - 10.10.1.2:8000
+ * - localhost
+ * - localhost:8001
+ * - [::1]:8000
+ * - [badc0de::1]
+ *
+ * \param url The URL string to take apart.
+ * \param host To return the copied host part of \a url.
+ * \param hostlen The maximum length of \a host.
+ * \param port To return the port number (if any) of \a url.
+ *
+ * \return Pointer to \a host, or NULL if failed.
+ * If NULL is returned, \a host and \a portnum are undefined. If no
+ * port number was present in \a url, \a portnum is set to -1.
+ *
+ * \sa RFC 3986, 3.2.2/3.2.3
+ */
+char *parse_url(const char *url,
+ char *host, ssize_t hostlen,
+ int32_t *port)
+{
+ const char *o = url;
+ char *c = host, *end = c + (hostlen - 1);
+
+ *port = -1;
+
+ if (o == NULL || hostlen < 1)
+ goto failed;
+
+ if (*o == '[') {
+ for (++o; (*c = *o == ']' ? '\0' : *o); c++, o++)
+ if (c == end)
+ goto failed;
+
+ if (*o++ != ']' || (*o != '\0' && *o != ':'))
+ goto failed;
+ } else {
+ for (; (*c = *o == ':'? '\0' : *o); c++, o++)
+ if (c == end)
+ goto failed;
+ }
+
+ if (*o == ':')
+ if (para_atoi32(++o, port) < 0 ||
+ *port < 0 || *port > 0xffff)
+ goto failed;
+
+ if (host_string_ok(host))
+ return host;
+failed:
+ *host = '\0';
+ return NULL;
+}
/**
- * initialize a struct sockaddr_in
- * @param addr A pointer to the struct to be initialized
- * @param port The port number to use
- * @param he The address to use
+ * Determine the socket type for a given layer-4 protocol.
+ *
+ * \param l4type The symbolic name of the transport-layer protocol.
*
- * If \a he is null (server mode), \a addr->sin_addr is initialized with \p INADDR_ANY.
- * Otherwise, the address given by \a he is copied to addr.
+ * \sa ip(7), socket(2)
*/
-void init_sockaddr(struct sockaddr_in *addr, int port, const struct hostent *he)
+static inline int sock_type(const unsigned l4type)
{
- /* host byte order */
- addr->sin_family = AF_INET;
- /* short, network byte order */
- addr->sin_port = htons(port);
- if (he)
- addr->sin_addr = *((struct in_addr *)he->h_addr);
- else
- addr->sin_addr.s_addr = INADDR_ANY;
- /* zero the rest of the struct */
- memset(&addr->sin_zero, '\0', 8);
+ switch (l4type) {
+ case IPPROTO_UDP: return SOCK_DGRAM;
+ case IPPROTO_TCP: return SOCK_STREAM;
+ case IPPROTO_DCCP: return SOCK_DCCP;
+ }
+ return -1; /* not supported here */
}
-/*
- * send out a buffer, resend on short writes
- * @param fd the file descriptor
- * @param buf The buffer to be sent
- * @len The length of \a buf
- *
- * Due to circumstances beyond your control, the kernel might not send all the
- * data out in one chunk, and now, my friend, it's up to us to get the data out
- * there (Beej's Guide to Network Programming).
+/**
+ * Pretty-print transport-layer name.
+ */
+static const char *layer4_name(const unsigned l4type)
+{
+ switch (l4type) {
+ case IPPROTO_UDP: return "UDP";
+ case IPPROTO_TCP: return "TCP";
+ case IPPROTO_DCCP: return "DCCP";
+ }
+ return "UNKNOWN PROTOCOL";
+}
+
+/**
+ * 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).
*/
-static int sendall(int fd, const char *buf, size_t *len)
+int makesock(unsigned l3type, unsigned l4type, int passive,
+ const char *host, unsigned short port_number)
{
- int total = 0; /* how many bytes we've sent */
- int bytesleft = *len; /* how many we have left to send */
- int n = -1;
-
- while (total < *len) {
- n = send(fd, buf + total, bytesleft, 0);
- if (n == -1)
- break;
- total += n;
- bytesleft -= n;
- if (total < *len)
- PARA_DEBUG_LOG("short write (%zd byte(s) left)",
- *len - total);
+ struct addrinfo *local = NULL, *src,
+ *remote = NULL, *dst, hints;
+ int rc, on = 1, sockfd = -1,
+ socktype = sock_type(l4type);
+ char port[6]; /* port number has at most 5 digits */
+
+ sprintf(port, "%u", port_number);
+ /* Set up address hint structure */
+ memset(&hints, 0, sizeof(hints));
+ hints.ai_family = l3type;
+ hints.ai_socktype = socktype;
+ /*
+ * getaddrinfo does not support SOCK_DCCP, so for the sake of lookup
+ * (and only then) pretend to be UDP.
+ */
+ if (l4type == IPPROTO_DCCP)
+ hints.ai_socktype = SOCK_DGRAM;
+
+ /* only use addresses available on the host */
+ hints.ai_flags = AI_ADDRCONFIG;
+ if (l3type == AF_INET6)
+ /* use v4-mapped-v6 if no v6 addresses found */
+ hints.ai_flags |= AI_V4MAPPED | AI_ALL;
+
+ if (passive && host == NULL)
+ hints.ai_flags |= AI_PASSIVE;
+
+ /* 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? host : (passive? "[loopback]" : "[localhost]"),
+ port, gai_strerror(rc));
+ return -E_ADDRESS_LOOKUP;
+ }
+
+ /* 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)
+ goto get_next_dst; /* v4 -> v6 is not possible */
+
+ 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. 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));
+ return -ERRNO_TO_PARA_ERROR(errno);
+ }
+
+ if (src) {
+ if (bind(sockfd, src->ai_addr, src->ai_addrlen) < 0) {
+ close(sockfd);
+ goto get_next_src;
+ }
+ if (!dst) /* bind-only completed successfully */
+ break;
+ }
+
+ if (dst && connect(sockfd, dst->ai_addr, dst->ai_addrlen) == 0)
+ 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)) /* restart inner loop */
+ dst = remote;
+ }
+ if (local)
+ freeaddrinfo(local);
+ if (remote)
+ freeaddrinfo(remote);
+
+ if (src == NULL && dst == NULL) {
+ 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);
}
- *len = total; /* return number actually sent here */
- return n == -1? -E_SEND : 1; /* return 1 on success */
+ return sockfd;
}
/**
- * encrypt and send buffer
- * @param fd: the file descriptor
- * @param buf the buffer to be encrypted and sent
- * @param len the length of \a buf
+ * 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.
*
- * Check if encrytion is available. If yes, encrypt the given buffer. Send out
- * the buffer, encrypted or not, and try to resend the remaing part in case of
- * short writes.
+ * \return Positive integer (socket descriptor) on success, negative value
+ * otherwise.
*
- * @return Positive on success, \p -E_SEND on errors.
+ * \sa makesock(), ip(7), ipv6(7), bind(2), listen(2).
*/
-int send_bin_buffer(int fd, const char *buf, size_t len)
+int para_listen(unsigned l3type, unsigned l4type, unsigned short port)
{
+ int ret, fd = makesock(l3type, l4type, 1, NULL, port);
+
+ if (fd > 0) {
+ ret = listen(fd, BACKLOG);
+ if (ret < 0) {
+ close(fd);
+ return -ERRNO_TO_PARA_ERROR(errno);
+ }
+ PARA_INFO_LOG("listening on %s port %u, fd %d\n",
+ 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).
+ */
+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;
- crypt_function *cf = NULL;
- if (!len)
- PARA_CRIT_LOG("%s", "len == 0\n");
- if (fd + 1 <= cda_size)
- cf = crypt_data_array[fd].send;
- if (cf) {
- void *private = crypt_data_array[fd].private_data;
- unsigned char *outbuf = para_malloc(len);
- (*cf)(len, (unsigned char *)buf, outbuf, private);
- ret = sendall(fd, (char *)outbuf, &len);
- free(outbuf);
+ 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));
+ sprintf(output, "(unknown)");
} else
- ret = sendall(fd, buf, &len);
- return ret;
+ sprintf(output, "%s#%s", hbuf, sbuf);
+ return output;
}
/**
- * encrypt and send null terminated buffer.
- * @param fd the file descriptor
- * @param buf the null-terminated buffer to be send
+ * Look up the local or remote side of a connected socket structure.
*
- * This is equivalent to send_bin_buffer(fd, buf, strlen(buf)).
+ * \param fd The socket descriptor of the connected socket.
+ * \param getname Either \p getsockname() for local, or \p getpeername() for
+ * remote side.
*
- * @return Positive on success, \p -E_SEND on errors.
+ * \return A static character string identifying hostname and port of the
+ * chosen side.
+ *
+ * \sa getsockname(2), getpeername(2).
*/
-int send_buffer(int fd, const char *buf)
+static char *__get_sock_name(int fd, int (*getname)(int, struct sockaddr*,
+ socklen_t *))
{
- return send_bin_buffer(fd, buf, strlen(buf));
+ 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));
+ return dont_know;
+ }
+ return host_and_port((struct sockaddr *)&ss, sslen);
}
-
/**
- * send and encrypt a buffer given by a format string
- * @param fd the file descriptor
- * @param fmt a format string
+ * Look up the local side of a connected socket structure.
+ *
+ * \param sockfd The file descriptor of the socket.
*
- * @return Positive on success, \p -E_SEND on errors.
+ * \return A pointer to a static buffer containing hostname an port. This
+ * buffer must not be freed by the caller.
+ *
+ * \sa remote_name().
*/
-__printf_2_3 int send_va_buffer(int fd, const char *fmt, ...)
+char *local_name(int sockfd)
{
- char *msg;
- int ret;
-
- PARA_VSPRINTF(fmt, msg);
- ret = send_buffer(fd, msg);
- free(msg);
- return ret;
+ return __get_sock_name(sockfd, getsockname);
}
/**
- * receive and decrypt.
+ * Look up the remote side of a connected socket structure.
*
- * @param fd the file descriptor
- * @param buf the buffer to write the decrypted data to
- * @param size the size of @param buf
+ * \param sockfd The file descriptor of the socket.
*
- * Receive at most \a size bytes from filedescriptor fd. If encrytion is
- * available, decrypt the received buffer.
+ * \return Analogous to the return value of \ref local_name() but for the
+ * remote side.
*
- * @return the number of bytes received on success. On receive errors, -E_RECV
- * is returned. On crypt errors, the corresponding crypt error number is
- * returned.
- * \sa recv(2)
+ * \sa local_name().
*/
-__must_check int recv_bin_buffer(int fd, char *buf, ssize_t size)
+char *remote_name(int sockfd)
{
- int n;
- crypt_function *cf = NULL;
-
- if (fd + 1 <= cda_size)
- cf = crypt_data_array[fd].recv;
- if (cf) {
- unsigned char *tmp = para_malloc(size);
- void *private = crypt_data_array[fd].private_data;
- n = recv(fd, tmp, size, 0);
- if (n > 0)
- (*cf)(n, tmp, (unsigned char *)buf, private);
- free(tmp);
- } else
- n = recv(fd, buf, size, 0);
- if (n == -1)
- n = -E_RECV;
- return n;
+ return __get_sock_name(sockfd, getpeername);
}
/**
- * receive, decrypt and write terminating NULL byte
+ * 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.
*
- * @param fd the file descriptor
- * @param buf the buffer to write the decrypted data to
- * @param size the size of \a buf
+ * \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 a binary buffer.
*
- * Read and decrypt at most size - 1 bytes from file descriptor \a fd and write
- * a NULL byte at the end of the received data.
+ * \param fd The file descriptor.
+ * \param buf The buffer to be sent.
+ * \param len The length of \a buf.
*
-*/
-int recv_buffer(int fd, char *buf, ssize_t size)
+ * Send out the buffer and try to resend the remaining part in case of short
+ * writes.
+ *
+ * \return Standard.
+ */
+int send_bin_buffer(int fd, const char *buf, size_t len)
{
- int n;
-
- n = recv_bin_buffer(fd, buf, size - 1);
- if (n >= 0)
- buf[n] = '\0';
- else
- *buf = '\0';
- return n;
+ if (!len)
+ PARA_CRIT_LOG("len == 0\n");
+ return write_all(fd, buf, &len);
}
/**
- * wrapper around gethostbyname
+ * Send a \p NULL-terminated buffer.
*
- * \param host hostname or IPv4 address
- * \param ret the hostent structure is returned here
+ * \param fd The file descriptor.
+ * \param buf The null-terminated buffer to be send.
*
- * \return positive on success, negative on errors. On success, \a ret
- * contains the return value of the underlying gethostbyname() call.
+ * This is equivalent to send_bin_buffer(fd, buf, strlen(buf)).
*
- * \sa gethostbyname(2)
+ * \return Standard.
*/
-int get_host_info(char *host, struct hostent **ret)
+int send_buffer(int fd, const char *buf)
{
- PARA_INFO_LOG("getting host info of %s\n", host);
- /* FIXME: gethostbyname() is obsolete */
- *ret = gethostbyname(host);
- return *ret? 1 : -E_HOST_INFO;
+ return send_bin_buffer(fd, buf, strlen(buf));
}
/**
- * a wrapper around socket(2)
+ * Send a buffer given by a format string.
*
- * Create an IPv4 socket for sequenced, reliable, two-way, connection-based
- * byte streams.
+ * \param fd The file descriptor.
+ * \param fmt A format string.
*
- * @return The socket fd on success, -E_SOCKET on errors.
- * \sa socket(2)
+ * \return Standard.
*/
-int get_socket(void)
+__printf_2_3 int send_va_buffer(int fd, const char *fmt, ...)
{
- int socket_fd;
+ char *msg;
+ int ret;
- if ((socket_fd = socket(AF_INET, SOCK_STREAM, 0)) == -1)
- return -E_SOCKET;
- return socket_fd;
+ PARA_VSPRINTF(fmt, msg);
+ ret = send_buffer(fd, msg);
+ free(msg);
+ return ret;
}
/**
- * a wrapper around connect(2)
+ * Receive data from a file descriptor.
+ *
+ * \param fd The file descriptor.
+ * \param buf The buffer to write the data to.
+ * \param size The size of \a buf.
*
- * @param fd the file descriptor
- * @param their_addr the address to connect
+ * Receive at most \a size bytes from file descriptor \a fd.
*
- * @return \p -E_CONNECT on errors, 1 on success
- * \sa connect(2)
+ * \return The number of bytes received on success, negative on errors, zero if
+ * the peer has performed an orderly shutdown.
+ *
+ * \sa recv(2).
*/
-int para_connect(int fd, struct sockaddr_in *their_addr)
+__must_check int recv_bin_buffer(int fd, char *buf, size_t size)
{
- int ret;
+ ssize_t n;
- if ((ret = connect(fd, (struct sockaddr *)their_addr,
- sizeof(struct sockaddr))) == -1)
- return -E_CONNECT;
- return 1;
+ n = recv(fd, buf, size, 0);
+ if (n == -1)
+ return -ERRNO_TO_PARA_ERROR(errno);
+ return n;
}
/**
- * paraslash's wrapper around the accept system call
+ * Receive and write terminating NULL byte.
*
- * @param fd the listening socket
- * @param addr structure which is filled in with the address of the peer socket
- * @param size should contain the size of the structure pointed to by \a addr
+ * \param fd The file descriptor.
+ * \param buf The buffer to write the data to.
+ * \param size The size of \a buf.
*
- * \sa accept(2).
+ * Read at most \a size - 1 bytes from file descriptor \a fd and
+ * write a NULL byte at the end of the received data.
+ *
+ * \return The return value of the underlying call to \a recv_bin_buffer().
+ *
+ * \sa recv_bin_buffer()
*/
-int para_accept(int fd, void *addr, socklen_t size)
+int recv_buffer(int fd, char *buf, size_t size)
{
- int new_fd;
+ int n;
- new_fd = accept(fd, (struct sockaddr *) addr, &size);
- return new_fd == -1? -E_ACCEPT : new_fd;
+ assert(size);
+ n = recv_bin_buffer(fd, buf, size - 1);
+ if (n >= 0)
+ buf[n] = '\0';
+ else
+ *buf = '\0';
+ return n;
}
-static int setserversockopts(int socket_fd)
+/**
+ * Wrapper around the accept system call.
+ *
+ * \param fd The listening socket.
+ * \param addr Structure which is filled in with the address of the peer socket.
+ * \param size Should contain the size of the structure pointed to by \a addr.
+ *
+ * Accept incoming connections on \a addr. Retry if interrupted.
+ *
+ * \return The new file descriptor on success, negative on errors.
+ *
+ * \sa accept(2).
+ */
+int para_accept(int fd, void *addr, socklen_t size)
{
- int yes = 1;
+ int new_fd;
- if (setsockopt(socket_fd, SOL_SOCKET, SO_REUSEADDR, &yes,
- sizeof(int)) == -1)
- return -E_SETSOCKOPT;
- return 1;
+ do
+ new_fd = accept(fd, (struct sockaddr *) addr, &size);
+ while (new_fd < 0 && errno == EINTR);
+ return new_fd < 0? -ERRNO_TO_PARA_ERROR(errno) : new_fd;
}
/**
- * 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.
*
* \return Positive on success, \p -E_NAME_TOO_LONG if \a name is longer
* than \p UNIX_PATH_MAX.
*/
-int init_unix_addr(struct sockaddr_un *u, const char *name)
+static int init_unix_addr(struct sockaddr_un *u, const char *name)
{
if (strlen(name) >= UNIX_PATH_MAX)
return -E_NAME_TOO_LONG;
}
/**
- * prepare, create, and bind and socket for local communication
+ * Prepare, create, and bind a socket for local communication.
*
- * \param name the socket pathname
- * \param unix_addr pointer to the \p AF_UNIX socket structure
- * \param mode the desired mode of the socket
+ * \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 functions creates a local socket for sequenced, reliable,
+ * This function creates a local socket for sequenced, reliable,
* two-way, connection-based byte streams.
+ *
+ * \return The file descriptor, on success, negative on errors.
+ *
* \sa socket(2)
* \sa bind(2)
* \sa chmod(2)
*/
-int create_pf_socket(const char *name, struct sockaddr_un *unix_addr, int mode)
+int create_local_socket(const char *name, struct sockaddr_un *unix_addr,
+ mode_t mode)
{
int fd, ret;
- fd = socket(PF_UNIX, SOCK_STREAM, 0);
- if (fd < 0)
- return -E_SOCKET;
-// unlink(name);
ret = init_unix_addr(unix_addr, name);
if (ret < 0)
return ret;
- if (bind(fd, (struct sockaddr *) unix_addr, UNIX_PATH_MAX) < 0)
- return -E_BIND;
+ 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);
+ if (ret < 0) {
+ ret = -ERRNO_TO_PARA_ERROR(errno);
+ goto err;
+ }
+ ret = -E_CHMOD;
if (chmod(name, mode) < 0)
- return -E_CHMOD;
+ goto err;
return fd;
+err:
+ close(fd);
+ return ret;
+}
+
+/**
+ * Prepare, create, and connect to a Unix domain socket for local communication.
+ *
+ * \param name The socket pathname.
+ *
+ * This function creates a local socket for sequenced, reliable, two-way,
+ * connection-based byte streams.
+ *
+ * \return The file descriptor, on success, negative on errors.
+ *
+ * \sa create_local_socket(), unix(7), connect(2).
+ */
+int create_remote_socket(const char *name)
+{
+ struct sockaddr_un unix_addr;
+ int fd, ret;
+
+ 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);
+ goto err;
+ }
+ return fd;
+err:
+ close(fd);
+ return ret;
}
#ifndef HAVE_UCRED
- struct ucred {
- uid_t uid, pid, gid;
-};
ssize_t send_cred_buffer(int sock, char *buf)
{
return send_buffer(sock, buf);
}
#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 ist returned.
- * \sa okir's Black Hats Manual
- * \sa sendmsg(2)
+ * error, \p -E_SENDMSG is returned.
+ *
+ * \sa sendmsg(2), okir's Black Hats Manual.
*/
ssize_t send_cred_buffer(int sock, char *buf)
{
- char control[sizeof(struct cmsghdr) + 10];
+ char control[sizeof(struct cmsghdr) + sizeof(struct ucred)];
struct msghdr msg;
struct cmsghdr *cmsg;
static struct iovec iov;
return ret;
}
-static void dispose_fds(int *fds, int num)
+static void dispose_fds(int *fds, unsigned num)
{
int i;
}
/**
- * 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)
{
}
#endif /* HAVE_UCRED */
-/** how many pending connections queue will hold */
-#define BACKLOG 10
-
/**
- * create a socket, bind it and listen
- * \param port the tcp port to listen on
+ * Receive a buffer and check for a pattern.
*
- * \return The file descriptor of the created socket, negative
- * on errors.
- *
- * \sa get_socket()
- * \sa setsockopt(2)
- * \sa bind(2)
- * \sa listen(2)
- */
-int init_tcp_socket(int port)
-{
- struct sockaddr_in my_addr;
- int fd, ret = get_socket();
-
- if (ret < 0)
- return ret;
- fd = ret;
- ret = setserversockopts(fd);
- if (ret < 0)
- goto err;
- init_sockaddr(&my_addr, port, NULL);
- ret = -E_BIND;
- if (bind(fd, (struct sockaddr *)&my_addr,
- sizeof(struct sockaddr)) == -1) {
- PARA_CRIT_LOG("bind error: %s\n", strerror(errno));
- goto err;
- }
- ret = -E_LISTEN;
- if (listen(fd, BACKLOG) == -1)
- goto err;
- PARA_INFO_LOG("listening on port %d, fd %d\n", port, fd);
- return fd;
-err:
- close(fd);
- return ret;
-}
-
-/**
- * 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.
*
- * This function creates a buffer of size \a bufsize and tries
- * to receive at most \a bufsize bytes from file descriptor \a fd.
- * 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)
+ * This function tries to receive at most \a bufsize bytes from file descriptor
+ * \a fd. 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).
*/
int recv_pattern(int fd, const char *pattern, size_t bufsize)
{
size_t len = strlen(pattern);
char *buf = para_malloc(bufsize + 1);
- int ret = -E_RECV_PATTERN, n = recv_buffer(fd, buf, bufsize);
+ int ret = -E_RECV_PATTERN, n = recv_buffer(fd, buf, bufsize + 1);
if (n < len)
goto out;
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);
}
projects / paraslash.git / blobdiff