/*
- * Copyright (C) 2005-2008 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2005-2009 Andre Noll <maan@systemlinux.org>
*
* 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 <netdb.h>
/* At least NetBSD needs these. */
#endif
#include <dirent.h>
+#include <regex.h>
#include "para.h"
#include "error.h"
crypt_data_array[fd].private_data = NULL;
}
+/**
+ * Match string as a candidate IPv4 address.
+ *
+ * \param address The string to match.
+ * \return True if \a address has "dot-quad" format.
+ */
+static bool is_v4_dot_quad(const char *address)
+{
+ bool result;
+ regex_t r;
+
+ assert(!regcomp(&r, "^([0-9]+\\.){3}[0-9]+$", REG_EXTENDED|REG_NOSUB));
+ result = regexec(&r, address, 0, NULL, 0) == 0;
+ regfree(&r);
+ return result;
+}
+
+/**
+ * Perform basic syntax checking on the host-part of an URL:
+ *
+ * - 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.
+ *
+ * \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
+ */
+static bool host_string_ok(const char *host)
+{
+ 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;
+}
/**
* Determine the socket type for a given layer-4 protocol.
return host_and_port((struct sockaddr *)&ss, sslen);
}
+/**
+ * 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);
struct in_addr ia = {.s_addr = 0};
if (ss->ss_family == AF_INET)
- ia.s_addr = ((struct sockaddr_in *)ss)->sin_addr.s_addr;
+ 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;
* \param len The length of \a buf.
*
* Check if encryption 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.
+ * out the buffer, encrypted or not, and try to resend the remaining part in
+ * case of short writes.
*
* \return Standard.
*/
*/
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;
free(buf);
return ret;
}
-
-static int resolve(const char *hostname, unsigned short port,
- struct sockaddr_in *addr)
-{
- struct hostent *host;
-
- assert(hostname);
- host = gethostbyname(hostname);
- if (!host)
- return -ERRNO_TO_PARA_ERROR(h_errno);
- if (addr) {
- memcpy(&addr->sin_addr, host->h_addr_list[0], host->h_length);
- addr->sin_port = port;
- }
- return 1;
-}
-
-/*
- * Create an UDP socket.
- *
- * If the given address is a multicast adress, the socket will be set
- * to use the multicast TTL ttl and sets the datagrams to loop back.
- *
- * \return The fd of the socket on success, negative on errors.
- */
-static int create_udp_socket(struct sockaddr_in *addr,
- unsigned short port, unsigned char ttl)
-{
- int ret, fd, yes = 1;
-
- assert(addr);
- ret = socket(PF_INET, SOCK_DGRAM, 0);
- if (ret < 0)
- return -ERRNO_TO_PARA_ERROR(errno);
- fd = ret;
- /* reuse addresses */
- ret = setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes));
- if (ret < 0) {
- ret = -ERRNO_TO_PARA_ERROR(errno);
- goto err;
- }
- addr->sin_family = AF_INET;
- addr->sin_port = htons(port);
- /* set the TTL and turn on multicast loop */
- if (IN_MULTICAST(htonl(addr->sin_addr.s_addr))) {
- unsigned char loop = 1;
- ret = setsockopt(fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl,
- sizeof(ttl));
- if (ret < 0) {
- ret = -ERRNO_TO_PARA_ERROR(errno);
- goto err;
- }
- ret = setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP, &loop,
- sizeof(loop));
- if (ret < 0) {
- ret = -ERRNO_TO_PARA_ERROR(errno);
- goto err;
- }
- }
- return fd;
-err:
- close(fd);
- return ret;
-}
-
-/**
- * Create and connect a sending UDP socket.
- *
- * \param hostname Where to send to (name or IPv4 address).
- * \param port The udp port to use.
- * \param ttl Time to live (only relevant for multicast).
- *
- * \return The fd of the socket on success, negative on error.
- */
-int create_udp_send_socket(char *hostname, unsigned short port,
- unsigned char ttl)
-{
- struct sockaddr_in addr;
- int fd, ret = resolve(hostname, port, &addr);
-
- if (ret < 0)
- return ret;
- ret = create_udp_socket(&addr, port, ttl);
- if (ret < 0)
- return ret;
- fd = ret;
- ret = connect(fd, (struct sockaddr *)&addr, sizeof(addr));
- if (ret >= 0)
- return fd;
- ret = -ERRNO_TO_PARA_ERROR(errno);
- close(fd);
- return ret;
-}
-
-/**
- * Create and bind a receiving UDP socket.
- *
- * Bind the created UDP socket to \a hostname, and add multicast membership if
- * hostname is a multicast hostname.
- *
- * \param hostname Name or IPv4 address to receive from.
- * \param port The udp port.
- *
- * \return The fd of the socket on success, negative on errors.
- */
-int create_udp_recv_socket(char *hostname, unsigned short port)
-{
- struct sockaddr_in addr;
- int fd, ret = resolve(hostname, port, &addr);
-
- if (ret < 0)
- memset(&addr.sin_addr, 0, sizeof(addr.sin_addr));
- ret = create_udp_socket(&addr, port, 1);
- if (ret < 0)
- return ret;
- fd = ret;
- ret = bind(fd, (struct sockaddr *)&addr, sizeof(addr));
- if (ret < 0) {
- ret = -ERRNO_TO_PARA_ERROR(errno);
- goto err;
- }
- /* Add multicast membership */
- if (IN_MULTICAST(htonl(addr.sin_addr.s_addr))) {
- struct ip_mreq mreq;
-
- mreq.imr_multiaddr.s_addr = addr.sin_addr.s_addr;
- mreq.imr_interface.s_addr = htonl(INADDR_ANY);
- ret = setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP,
- &mreq, sizeof(mreq));
- if (ret < 0) {
- ret = -ERRNO_TO_PARA_ERROR(errno);
- goto err;
- }
- }
- return fd;
-err:
- close(fd);
- return ret;
-}
projects / paraslash.git / blobdiff