/*
- $Id: socket.c,v 1.1 2009-10-26 12:35:56 franklahm Exp $
+ $Id: socket.c,v 1.6 2010-01-05 19:05:52 franklahm Exp $
Copyright (c) 2009 Frank Lahm <franklahm@gmail.com>
This program is free software; you can redistribute it and/or modify
GNU General Public License for more details.
*/
+/*!
+ * @file
+ * Netatalk utility functions
+ */
+
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif /* HAVE_CONFIG_H */
#include <unistd.h>
#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <arpa/inet.h>
+#include <netinet/in.h>
+#include <stdlib.h>
+#include <string.h>
+
+static char ipv4mapprefix[] = {0,0,0,0,0,0,0,0,0,0,0xff,0xff};
+/*!
+ * @brief set or unset non-blocking IO on a fd
+ *
+ * @param fd (r) File descriptor
+ * @param cmd (r) 0: disable non-blocking IO, ie block\n
+ * <>0: enable non-blocking IO
+ *
+ * @returns 0 on success, -1 on failure
+ */
int setnonblock(int fd, int cmd)
{
int ofdflags;
return 0;
}
+
+/*!
+ * @brief convert an IPv4 or IPv6 address to a static string using inet_ntop
+ *
+ * IPv6 mapped IPv4 addresses are returned as IPv4 addreses eg
+ * ::ffff:10.0.0.0 is returned as "10.0.0.0".
+ *
+ * @param sa (r) pointer to an struct sockaddr
+ *
+ * @returns pointer to a static string cotaining the converted address as string.\n
+ * On error pointers to "0.0.0.0" or "::0" are returned.
+ */
+const char *getip_string(const struct sockaddr *sa)
+{
+ static char ip4[INET_ADDRSTRLEN];
+ static char ip6[INET6_ADDRSTRLEN];
+
+ switch (sa->sa_family) {
+
+ case AF_INET: {
+ const struct sockaddr_in *sai4 = (const struct sockaddr_in *)sa;
+ if ((inet_ntop(AF_INET, &(sai4->sin_addr), ip4, INET_ADDRSTRLEN)) == NULL)
+ return "0.0.0.0";
+ return ip4;
+ }
+ case AF_INET6: {
+ const struct sockaddr_in6 *sai6 = (const struct sockaddr_in6 *)sa;
+ if ((inet_ntop(AF_INET6, &(sai6->sin6_addr), ip6, INET6_ADDRSTRLEN)) == NULL)
+ return "::0";
+
+ /* Deal with IPv6 mapped IPv4 addresses*/
+ if ((memcmp(sai6->sin6_addr.s6_addr, ipv4mapprefix, sizeof(ipv4mapprefix))) == 0)
+ return (strrchr(ip6, ':') + 1);
+ return ip6;
+ }
+ default:
+ return "getip_string ERROR";
+ }
+
+ /* We never get here */
+}
+
+/*!
+ * @brief return port number from struct sockaddr
+ *
+ * @param sa (r) pointer to an struct sockaddr
+ *
+ * @returns port as unsigned int
+ */
+unsigned int getip_port(const struct sockaddr *sa)
+{
+ if (sa->sa_family == AF_INET) { /* IPv4 */
+ const struct sockaddr_in *sai4 = (const struct sockaddr_in *)sa;
+ return ntohs(sai4->sin_port);
+ } else { /* IPv6 */
+ const struct sockaddr_in6 *sai6 = (const struct sockaddr_in6 *)sa;
+ return ntohs(sai6->sin6_port);
+ }
+
+ /* We never get here */
+}
+
+/*!
+ * @brief apply netmask to IP (v4 or v6)
+ *
+ * Modifies IP address in sa->sin[6]_addr-s[6]_addr. The caller is responsible
+ * for passing a value for mask that is sensible to the passed address,
+ * eg 0 <= mask <= 32 for IPv4 or 0<= mask <= 128 for IPv6. mask > 32 for
+ * IPv4 is treated as mask = 32, mask > 128 is set to 128 for IPv6.
+ *
+ * @param ai (rw) pointer to an struct sockaddr
+ * @parma mask (r) number of maskbits
+ */
+void apply_ip_mask(struct sockaddr *sa, uint32_t mask)
+{
+
+ switch (sa->sa_family) {
+ case AF_INET: {
+ if (mask >= 32)
+ return;
+
+ struct sockaddr_in *si = (struct sockaddr_in *)sa;
+ uint32_t nmask = mask ? ~((1 << (32 - mask)) - 1) : 0;
+ si->sin_addr.s_addr &= htonl(nmask);
+ break;
+ }
+ case AF_INET6: {
+ if (mask >= 128)
+ return;
+
+ int i, maskbytes, maskbits;
+ struct sockaddr_in6 *si6 = (struct sockaddr_in6 *)sa;
+
+ /* Deal with IPv6 mapped IPv4 addresses*/
+ if ((memcmp(si6->sin6_addr.s6_addr, ipv4mapprefix, sizeof(ipv4mapprefix))) == 0) {
+ mask += 96;
+ if (mask >= 128)
+ return;
+ }
+
+ maskbytes = (128 - mask) / 8; /* maskbytes really are those that will be 0'ed */
+ maskbits = mask % 8;
+
+ for (i = maskbytes - 1; i >= 0; i--)
+ si6->sin6_addr.s6_addr[15 - i] = 0;
+ if (maskbits)
+ si6->sin6_addr.s6_addr[15 - maskbytes] &= ~((1 << (8 - maskbits)) - 1);
+ break;
+ }
+ default:
+ break;
+ }
+}
+
+/*!
+ * @brief compare IP addresses for equality
+ *
+ * @param sa1 (r) pointer to an struct sockaddr
+ * @param sa2 (r) pointer to an struct sockaddr
+ *
+ * @returns Addresses are converted to strings and compared with strcmp and
+ * the result of strcmp is returned.
+ *
+ * @note IPv6 mapped IPv4 addresses are treated as IPv4 addresses.
+ */
+int compare_ip(const struct sockaddr *sa1, const struct sockaddr *sa2)
+{
+ int ret;
+ char *ip1;
+ const char *ip2;
+
+ ip1 = strdup(getip_string(sa1));
+ ip2 = getip_string(sa2);
+
+ ret = strcmp(ip1, ip2);
+
+ free(ip1);
+
+ return ret;
+}
projects / netatalk.git / blobdiff