xref: /minix3/minix/lib/libc/sys/recvfrom.c (revision 9d3fcac4cd94c99d6300bba3ab995f44571a4994)
1 #include <sys/cdefs.h>
2 #include "namespace.h"
3 
4 #include <assert.h>
5 #include <errno.h>
6 #include <stdlib.h>
7 #include <stdio.h>
8 #include <string.h>
9 #include <unistd.h>
10 #include <sys/ioctl.h>
11 #include <sys/socket.h>
12 #include <netinet/in.h>
13 
14 #include <net/gen/in.h>
15 #include <net/gen/tcp.h>
16 #include <net/gen/tcp_io.h>
17 #include <net/gen/udp.h>
18 #include <net/gen/udp_hdr.h>
19 #include <net/gen/udp_io.h>
20 
21 #include <net/gen/ip_hdr.h>
22 #include <net/gen/icmp_hdr.h>
23 
24 #define DEBUG 0
25 
26 static ssize_t _tcp_recvfrom(int sock, void *__restrict buffer, size_t length,
27 	int flags, struct sockaddr *__restrict address,
28 	socklen_t *__restrict address_len, nwio_tcpconf_t *tcpconfp);
29 static ssize_t _udp_recvfrom(int sock, void *__restrict buffer, size_t length,
30 	int flags, struct sockaddr *__restrict address,
31 	socklen_t *__restrict address_len, nwio_udpopt_t *udpoptp);
32 static ssize_t _uds_recvfrom_conn(int sock, void *__restrict buffer,
33 	size_t length, int flags, struct sockaddr *__restrict address,
34 	socklen_t *__restrict address_len, struct sockaddr_un *uds_addr);
35 static ssize_t _uds_recvfrom_dgram(int sock, void *__restrict buffer,
36 	size_t length, int flags, struct sockaddr *__restrict address,
37 	socklen_t *__restrict address_len);
38 
39 ssize_t recvfrom(int sock, void *__restrict buffer, size_t length,
40 	int flags, struct sockaddr *__restrict address,
41 	socklen_t *__restrict address_len)
42 {
43 	int r;
44 	nwio_tcpconf_t tcpconf;
45 	nwio_udpopt_t udpopt;
46 	struct sockaddr_un uds_addr;
47 	int uds_sotype = -1;
48 
49 #if DEBUG
50 	fprintf(stderr, "recvfrom: for fd %d\n", sock);
51 #endif
52 
53 	r= ioctl(sock, NWIOGTCPCONF, &tcpconf);
54 	if (r != -1 || errno != ENOTTY)
55 	{
56 		if (r == -1)
57 			return r;
58 		return _tcp_recvfrom(sock, buffer, length, flags,
59 			address, address_len, &tcpconf);
60 	}
61 
62 	r= ioctl(sock, NWIOGUDPOPT, &udpopt);
63 	if (r != -1 || errno != ENOTTY)
64 	{
65 		if (r == -1)
66 			return r;
67 		return _udp_recvfrom(sock, buffer, length, flags,
68 			address, address_len, &udpopt);
69 	}
70 
71 	r= ioctl(sock, NWIOGUDSSOTYPE, &uds_sotype);
72 	if (r != -1 || errno != ENOTTY)
73 	{
74 
75 		if (r == -1) {
76 			return r;
77 		}
78 
79 		if (uds_sotype == SOCK_DGRAM) {
80 			return _uds_recvfrom_dgram(sock, buffer,
81 				length, flags, address, address_len);
82 		} else {
83 			return _uds_recvfrom_conn(sock, buffer,
84 				length, flags, address, address_len,
85 				&uds_addr);
86 		}
87 	}
88 
89 	{
90 		ip_hdr_t *ip_hdr;
91        		int ihl, rd;
92 		icmp_hdr_t *icmp_hdr;
93 		struct sockaddr_in sin;
94 
95 		rd = read(sock, buffer, length);
96 
97 		if(rd < 0) return rd;
98 
99 		assert(rd >= sizeof(*ip_hdr));
100 
101 		ip_hdr= buffer;
102 
103 		if (address != NULL)
104 		{
105 			int len;
106 			memset(&sin, 0, sizeof(sin));
107 			sin.sin_family= AF_INET;
108 			sin.sin_addr.s_addr= ip_hdr->ih_src;
109 			sin.sin_len= sizeof(sin);
110 			len= *address_len;
111 			if (len > sizeof(sin))
112 				len= sizeof(sin);
113 			memcpy(address, &sin, len);
114 			*address_len= sizeof(sin);
115 		}
116 
117 		return rd;
118        }
119 
120 #if DEBUG
121 	fprintf(stderr, "recvfrom: not implemented for fd %d\n", sock);
122 #endif
123 	abort();
124 }
125 
126 static ssize_t _tcp_recvfrom(int sock, void *__restrict buffer, size_t length,
127 	int flags, struct sockaddr *__restrict address,
128 	socklen_t *__restrict address_len, nwio_tcpconf_t *tcpconfp)
129 {
130 	int r;
131 	size_t len;
132 	struct sockaddr_in sin;
133 
134 	if (flags != 0)
135 	{
136 #if DEBUG
137 		fprintf(stderr, "recvfrom(tcp): flags not implemented\n");
138 #endif
139 		errno= ENOSYS;
140 		return -1;
141 	}
142 
143 	r = read(sock, buffer, length);
144 
145 	if (r >= 0 && address != NULL)
146 	{
147 		sin.sin_family= AF_INET;
148 		sin.sin_addr.s_addr= tcpconfp->nwtc_remaddr;
149 		sin.sin_port= tcpconfp->nwtc_remport;
150 		sin.sin_len= sizeof(sin);
151 		len= *address_len;
152 		if (len > sizeof(sin))
153 			len= sizeof(sin);
154 		memcpy(address, &sin, len);
155 		*address_len= sizeof(sin);
156 	}
157 
158 	return r;
159 }
160 
161 static ssize_t _udp_recvfrom(int sock, void *__restrict buffer, size_t length,
162 	int flags, struct sockaddr *__restrict address,
163 	socklen_t *__restrict address_len, nwio_udpopt_t *udpoptp)
164 {
165 	int r, t_errno;
166 	size_t buflen, len;
167 	void *buf;
168 	udp_io_hdr_t *io_hdrp;
169 	struct sockaddr_in sin;
170 
171 	if (flags)
172 	{
173 #if DEBUG
174 		fprintf(stderr, "recvfrom(udp): flags not implemented\n");
175 #endif
176 		errno= ENOSYS;
177 		return -1;
178 	}
179 
180 	if (udpoptp->nwuo_flags & NWUO_RWDATONLY)
181 	{
182 		if (address != NULL &&
183 			(udpoptp->nwuo_flags & (NWUO_RA_SET | NWUO_RP_SET)) !=
184 			(NWUO_RA_SET | NWUO_RP_SET))
185 		{
186 
187 #if DEBUG
188 			fprintf(stderr,
189 			"recvfrom(udp): RWDATONLY on unconnected socket\n");
190 #endif
191 			errno= ENOTCONN;
192 			return -1;
193 		}
194 
195 		r= read(sock, buffer, length);
196 		if (r == -1)
197 			return r;
198 
199 		if (address != NULL)
200 		{
201 			sin.sin_family= AF_INET;
202 			sin.sin_addr.s_addr= udpoptp->nwuo_remaddr;
203 			sin.sin_port= udpoptp->nwuo_remport;
204 			sin.sin_len= sizeof(sin);
205 			len= *address_len;
206 			if (len > sizeof(sin))
207 				len= sizeof(sin);
208 			memcpy(address, &sin, len);
209 			*address_len= sizeof(sin);
210 		}
211 
212 		return r;
213 	}
214 
215 	buflen= sizeof(*io_hdrp) + length;
216 	if (buflen < length)
217 	{
218 		/* Overflow */
219 		errno= EMSGSIZE;
220 		return -1;
221 	}
222 	buf= malloc(buflen);
223 	if (buf == NULL)
224 		return -1;
225 
226 	r= read(sock, buf, buflen);
227 	if (r == -1)
228 	{
229 		t_errno= errno;
230 #if DEBUG
231 		fprintf(stderr, "recvfrom(udp): read failed: %s\n",
232 			strerror(errno));
233 		fprintf(stderr, "udp opt flags = 0x%x\n", udpoptp->nwuo_flags);
234 #endif
235 		free(buf);
236 		errno= t_errno;
237 		return -1;
238 	}
239 
240 	assert(r >= sizeof(*io_hdrp));
241 	length= r-sizeof(*io_hdrp);
242 
243 	io_hdrp= buf;
244 	memcpy(buffer, &io_hdrp[1], length);
245 
246 	if (address != NULL)
247 	{
248 		sin.sin_family= AF_INET;
249 		sin.sin_addr.s_addr= io_hdrp->uih_src_addr;
250 		sin.sin_port= io_hdrp->uih_src_port;
251 		sin.sin_len= sizeof(sin);
252 		len= *address_len;
253 		if (len > sizeof(sin))
254 			len= sizeof(sin);
255 		memcpy(address, &sin, len);
256 		*address_len= sizeof(sin);
257 	}
258 	free(buf);
259 	return length;
260 }
261 
262 static ssize_t _uds_recvfrom_conn(int sock, void *__restrict buffer,
263 	size_t length, int flags, struct sockaddr *__restrict address,
264 	socklen_t *__restrict address_len, struct sockaddr_un *uds_addr)
265 {
266 	int r;
267 	size_t len;
268 
269 	/* for connection oriented unix domain sockets (SOCK_STREAM /
270 	 * SOCK_SEQPACKET)
271 	 */
272 
273 	if (flags != 0)
274 	{
275 #if DEBUG
276 		fprintf(stderr, "recvfrom(uds): flags not implemented\n");
277 #endif
278 		errno= ENOSYS;
279 		return -1;
280 	}
281 
282 	r = read(sock, buffer, length);
283 
284 	if (r >= 0 && address != NULL)
285 	{
286 
287 		len= *address_len;
288 		if (len > sizeof(struct sockaddr_un))
289 			len= sizeof(struct sockaddr_un);
290 		memcpy(address, uds_addr, len);
291 		*address_len= sizeof(struct sockaddr_un);
292 	}
293 
294 	return r;
295 }
296 
297 static ssize_t _uds_recvfrom_dgram(int sock, void *__restrict buffer,
298 	size_t length, int flags, struct sockaddr *__restrict address,
299 	socklen_t *__restrict address_len)
300 {
301 	int r;
302 	size_t len;
303 
304 	/* for connectionless unix domain sockets (SOCK_DGRAM) */
305 
306 	if (flags != 0)
307 	{
308 #if DEBUG
309 		fprintf(stderr, "recvfrom(uds): flags not implemented\n");
310 #endif
311 		errno= ENOSYS;
312 		return -1;
313 	}
314 
315 	r = read(sock, buffer, length);
316 
317 	if (r >= 0 && address != NULL)
318 	{
319 		len= *address_len;
320 		if (len > sizeof(struct sockaddr_un))
321 			len= sizeof(struct sockaddr_un);
322 		ioctl(sock, NWIOGUDSFADDR, address);
323 		*address_len= sizeof(struct sockaddr_un);
324 	}
325 
326 	return r;
327 }
328 
329