2 $Id: socket.c,v 1.6 2010-01-05 19:05:52 franklahm Exp $
3 Copyright (c) 2009 Frank Lahm <franklahm@gmail.com>
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
18 * Netatalk utility functions
23 #endif /* HAVE_CONFIG_H */
27 #include <sys/types.h>
28 #include <sys/socket.h>
29 #include <arpa/inet.h>
30 #include <netinet/in.h>
35 #include <atalk/logger.h>
37 static char ipv4mapprefix[] = {0,0,0,0,0,0,0,0,0,0,0xff,0xff};
40 * @brief set or unset non-blocking IO on a fd
42 * @param fd (r) File descriptor
43 * @param cmd (r) 0: disable non-blocking IO, ie block\n
44 * <>0: enable non-blocking IO
46 * @returns 0 on success, -1 on failure
48 int setnonblock(int fd, int cmd)
53 if ((fdflags = ofdflags = fcntl(fd, F_GETFL, 0)) == -1)
57 fdflags |= O_NONBLOCK;
59 fdflags &= ~O_NONBLOCK;
61 if (fdflags != ofdflags)
62 if (fcntl(fd, F_SETFL, fdflags) == -1)
69 * non-blocking drop-in replacement for read with timeout using select
71 * @param socket (r) socket, if in blocking mode, pass "setnonblocking" arg as 1
72 * @param data (rw) buffer for the read data
73 * @param lenght (r) how many bytes to read
74 * @param setnonblocking (r) when non-zero this func will enable and disable non blocking
75 * io mode for the socket
76 * @param timeout (r) number of seconds to try reading
78 * @returns number of bytes actually read or -1 on fatal error
80 ssize_t readt(int socket, void *data, const size_t length, int setnonblocking, int timeout)
91 if (setnonblock(socket, 1) != 0)
95 while (stored < length) {
96 len = read(socket, (char *) data + stored, length - stored);
106 FD_SET(socket, &rfds);
107 while ((ret = select(socket + 1, &rfds, NULL, NULL, &tv)) < 1) {
110 LOG(log_warning, logtype_cnid, "select timeout 1s");
114 LOG(log_error, logtype_cnid, "select: %s", strerror(errno));
121 LOG(log_error, logtype_cnid, "read: %s", strerror(errno));
132 if (setnonblocking) {
133 if (setnonblock(socket, 0) != 0)
141 * @brief convert an IPv4 or IPv6 address to a static string using inet_ntop
143 * IPv6 mapped IPv4 addresses are returned as IPv4 addreses eg
144 * ::ffff:10.0.0.0 is returned as "10.0.0.0".
146 * @param sa (r) pointer to an struct sockaddr
148 * @returns pointer to a static string cotaining the converted address as string.\n
149 * On error pointers to "0.0.0.0" or "::0" are returned.
151 const char *getip_string(const struct sockaddr *sa)
153 static char ip4[INET_ADDRSTRLEN];
154 static char ip6[INET6_ADDRSTRLEN];
156 switch (sa->sa_family) {
159 const struct sockaddr_in *sai4 = (const struct sockaddr_in *)sa;
160 if ((inet_ntop(AF_INET, &(sai4->sin_addr), ip4, INET_ADDRSTRLEN)) == NULL)
165 const struct sockaddr_in6 *sai6 = (const struct sockaddr_in6 *)sa;
166 if ((inet_ntop(AF_INET6, &(sai6->sin6_addr), ip6, INET6_ADDRSTRLEN)) == NULL)
169 /* Deal with IPv6 mapped IPv4 addresses*/
170 if ((memcmp(sai6->sin6_addr.s6_addr, ipv4mapprefix, sizeof(ipv4mapprefix))) == 0)
171 return (strrchr(ip6, ':') + 1);
175 return "getip_string ERROR";
178 /* We never get here */
182 * @brief return port number from struct sockaddr
184 * @param sa (r) pointer to an struct sockaddr
186 * @returns port as unsigned int
188 unsigned int getip_port(const struct sockaddr *sa)
190 if (sa->sa_family == AF_INET) { /* IPv4 */
191 const struct sockaddr_in *sai4 = (const struct sockaddr_in *)sa;
192 return ntohs(sai4->sin_port);
194 const struct sockaddr_in6 *sai6 = (const struct sockaddr_in6 *)sa;
195 return ntohs(sai6->sin6_port);
198 /* We never get here */
202 * @brief apply netmask to IP (v4 or v6)
204 * Modifies IP address in sa->sin[6]_addr-s[6]_addr. The caller is responsible
205 * for passing a value for mask that is sensible to the passed address,
206 * eg 0 <= mask <= 32 for IPv4 or 0<= mask <= 128 for IPv6. mask > 32 for
207 * IPv4 is treated as mask = 32, mask > 128 is set to 128 for IPv6.
209 * @param ai (rw) pointer to an struct sockaddr
210 * @parma mask (r) number of maskbits
212 void apply_ip_mask(struct sockaddr *sa, uint32_t mask)
215 switch (sa->sa_family) {
220 struct sockaddr_in *si = (struct sockaddr_in *)sa;
221 uint32_t nmask = mask ? ~((1 << (32 - mask)) - 1) : 0;
222 si->sin_addr.s_addr &= htonl(nmask);
229 int i, maskbytes, maskbits;
230 struct sockaddr_in6 *si6 = (struct sockaddr_in6 *)sa;
232 /* Deal with IPv6 mapped IPv4 addresses*/
233 if ((memcmp(si6->sin6_addr.s6_addr, ipv4mapprefix, sizeof(ipv4mapprefix))) == 0) {
239 maskbytes = (128 - mask) / 8; /* maskbytes really are those that will be 0'ed */
242 for (i = maskbytes - 1; i >= 0; i--)
243 si6->sin6_addr.s6_addr[15 - i] = 0;
245 si6->sin6_addr.s6_addr[15 - maskbytes] &= ~((1 << (8 - maskbits)) - 1);
254 * @brief compare IP addresses for equality
256 * @param sa1 (r) pointer to an struct sockaddr
257 * @param sa2 (r) pointer to an struct sockaddr
259 * @returns Addresses are converted to strings and compared with strcmp and
260 * the result of strcmp is returned.
262 * @note IPv6 mapped IPv4 addresses are treated as IPv4 addresses.
264 int compare_ip(const struct sockaddr *sa1, const struct sockaddr *sa2)
270 ip1 = strdup(getip_string(sa1));
271 ip2 = getip_string(sa2);
273 ret = strcmp(ip1, ip2);