summaryrefslogtreecommitdiffstats
path: root/main/libc0.9.32/uClibc-0.9.33-avahi.patch
blob: 017ac5fef8e9d395176e16b201d5d58855febbd3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
From 5654318b39dae5e5a32e290849ec590cb85ee0b3 Mon Sep 17 00:00:00 2001
Message-Id: <5654318b39dae5e5a32e290849ec590cb85ee0b3.1322557154.git.n.voss@weinmann.de>
In-Reply-To: <cover.1322557154.git.n.voss@weinmann.de>
References: <cover.1322557154.git.n.voss@weinmann.de>
From: Nikolaus Voss <n.voss@weinmann.de>
Date: Mon, 28 Nov 2011 16:18:30 +0100
Subject: [PATCH 1/2] gethostbyaddr_r: add space for alias pointers
To: uclibc@uclibc.org

addr_list and alias where on the same buffer offset. This led
to corrupt addr_list which was overwritten by the resolved name.

Signed-off-by: Nikolaus Voss <n.voss@weinmann.de>
---
 libc/inet/resolv.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/libc/inet/resolv.c b/libc/inet/resolv.c
index 021d5bf..bc596b0 100644
--- a/libc/inet/resolv.c
+++ b/libc/inet/resolv.c
@@ -2402,6 +2402,8 @@ int gethostbyaddr_r(const void *addr, socklen_t addrlen,
 	 */
 #define in6 ((struct in6_addr *)in)
 	alias = (char **)buf;
+	buf += sizeof(alias) * 2;
+	buflen -= sizeof(alias) * 2;
 	addr_list = (struct in_addr**)buf;
 	buf += sizeof(*addr_list) * 2;
 	buflen -= sizeof(*addr_list) * 2;
-- 
1.7.5.4

From 5388e302e40b12fb6682899dd4206f3e3d7a84fa Mon Sep 17 00:00:00 2001
Message-Id: <5388e302e40b12fb6682899dd4206f3e3d7a84fa.1322557154.git.n.voss@weinmann.de>
In-Reply-To: <cover.1322557154.git.n.voss@weinmann.de>
References: <cover.1322557154.git.n.voss@weinmann.de>
From: Nikolaus Voss <n.voss@weinmann.de>
Date: Mon, 28 Nov 2011 16:22:42 +0100
Subject: [PATCH 2/2] Make link-local addresses resolvable via running
 avahi-daemon
To: uclibc@uclibc.org

nss-mdns is an extension to glibc to support resolution of link-local
(.local) addresses via GNU Name Service Switch (NSS) which redirects
the queries to a running avahi-daemon, which in turn does the resolution
via multicast DNS (mdns).

However, this does not work for uClibc, as it does not support NSS.

This patch integrates the nss-mdns approach into uClibc's resolver,
so getaddrinfo() and getnameinfo() calls get redirected to a running
avahi-daemon before trying to resolve via unicast DNS.

This increases the size of the library by 50 bytes on ARM.

Signed-off-by: Nikolaus Voss <n.voss@weinmann.de>
---
 extra/Configs/Config.in                          |   19 +++
 libc/inet/Makefile.in                            |    1 +
 libc/inet/avahi.c                                |  183 ++++++++++++++++++++++
 libc/inet/avahi.h                                |   33 ++++
 libc/inet/resolv.c                               |   23 +++-
 libc/sysdeps/linux/common/bits/kernel-features.h |    7 +-
 6 files changed, 259 insertions(+), 7 deletions(-)
 create mode 100644 libc/inet/avahi.c
 create mode 100644 libc/inet/avahi.h

diff --git a/extra/Configs/Config.in b/extra/Configs/Config.in
index e41adc4..6053a55 100644
--- a/extra/Configs/Config.in
+++ b/extra/Configs/Config.in
@@ -1268,6 +1268,25 @@ config UCLIBC_HAS_EXTRA_COMPAT_RES_STATE
 	  Answer Y if selecting UCLIBC_HAS_COMPAT_RES_STATE is not enough.
 	  As far as I can say, this should never be needed.
 
+config UCLIBC_HAS_AVAHI_RES
+	bool "Try to resolve link-local IP addresses via avahi-daemon"
+	default n
+	depends on UCLIBC_HAS_IPV4 || UCLIBC_HAS_IPV6
+	help
+	  Answer Y if you want to resolve .local addresses via multicast-dns.
+	  The queries are forwarded to a running avahi-daemon via a domain
+	  socket interface.
+	  Note that this might interfere with a .local domain on your DNS.
+	  Answering N saves around 50 bytes.
+
+config UCLIBC_AVAHI_SOCKET_PATH
+	string "Path to avahi unix domain socket"
+	default "/var/run/avahi-daemon/socket"
+	depends on UCLIBC_HAS_AVAHI_RES
+	help
+	  A running avahi-daemon creates a socket to listen for queries.
+	  Enter the path you configured your avahi-daemon to.
+
 config UCLIBC_HAS_LIBRESOLV_STUB
 	bool "Provide libresolv stub"
 	default n
diff --git a/libc/inet/Makefile.in b/libc/inet/Makefile.in
index d588220..7f436c9 100644
--- a/libc/inet/Makefile.in
+++ b/libc/inet/Makefile.in
@@ -33,6 +33,7 @@ CSRC-$(findstring y,$(UCLIBC_HAS_IPV4)$(UCLIBC_HAS_IPV6)) += \
 	dnslookup.c opennameservers.c closenameservers.c \
 	getnameinfo.c \
 	gethostent.c gethostent_r.c
+CSRC-$(UCLIBC_HAS_AVAHI_RES) += avahi.c
 CSRC-$(findstring y,$(UCLIBC_HAS_IPV4)$(UCLIBC_HAS_IPV6)) += \
 	get_hosts_byaddr_r.c get_hosts_byname_r.c \
 	gethostbyaddr_r.c gethostbyname_r.c gethostbyname2_r.c \
diff --git a/libc/inet/avahi.c b/libc/inet/avahi.c
new file mode 100644
index 0000000..11ce055
--- /dev/null
+++ b/libc/inet/avahi.c
@@ -0,0 +1,183 @@
+/*
+ *
+ * (C) 2011 Weinmann GmbH, Hamburg, Germany
+ *
+ * Author: Nikolaus Voss <n.voss@weinmann.de>
+ *
+ * Derived from avahi.c / nss-mdns by Lennart Poettering.
+ * Copyright 2004-2007 Lennart Poettering <mzaffzqaf (at) 0pointer (dot) de>
+ *
+ * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
+ *
+ */
+
+#include <arpa/inet.h>
+#include <fcntl.h>
+#include <not-cancel.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <sys/un.h>
+#include <unistd.h>
+
+#include "avahi.h"
+
+#define WHITESPACE " \t"
+
+static FILE *avahi_open_socket(void)
+{
+	int fd;
+	struct sockaddr_un sa;
+	FILE *f;
+
+	fd = socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0);
+
+	if (fd < 0)
+		return NULL;
+
+#ifndef __ASSUME_SOCK_CLOEXEC
+	fcntl_not_cancel(fd, F_SETFD, FD_CLOEXEC);
+#endif
+
+	memset(&sa, 0, sizeof(sa));
+	sa.sun_family = AF_UNIX;
+	strncpy(sa.sun_path, __UCLIBC_AVAHI_SOCKET_PATH__,
+		sizeof(sa.sun_path) - 1);
+	sa.sun_path[sizeof(sa.sun_path) - 1] = 0;
+
+	if (connect(fd, (struct sockaddr *) &sa, sizeof(sa)) < 0)
+		goto fail;
+
+	f = fdopen(fd, "r+");
+	if (!f)
+		goto fail;
+
+	return f;
+
+fail:
+	close(fd);
+
+	return NULL;
+}
+
+static int avahi_ends_with(const char *name, const char* suffix)
+{
+	size_t ln, ls;
+
+	if (!name || !suffix)
+		return 0;
+
+	if ((ls = strlen(suffix)) > (ln = strlen(name)))
+		return 0;
+
+	return strcasecmp(name + ln - ls, suffix) == 0;
+}
+
+int __avahi_resolve_name(int af, const char* name, void* data)
+{
+	FILE *f;
+	char *p;
+	int ret = -1;
+	char ln[256];
+
+	if (af != AF_INET && af != AF_INET6)
+		return ret;
+
+	if (!avahi_ends_with(name, ".local") &&
+	    !avahi_ends_with(name, ".local."))
+		return ret;
+
+	f = avahi_open_socket();
+	if (!f)
+		return ret;
+
+	fprintf(f, "RESOLVE-HOSTNAME-IPV%d %s\n", af == AF_INET ? 4 : 6, name);
+	fflush(f);
+
+	if (!fgets(ln, sizeof(ln), f))
+		goto finish;
+
+	if (ln[0] != '+') {
+		ret = 1;
+		goto finish;
+	}
+
+	p = ln + 1;
+	p += strspn(p, WHITESPACE);
+
+	/* Skip interface */
+	p += strcspn(p, WHITESPACE);
+	p += strspn(p, WHITESPACE);
+
+	/* Skip protocol */
+	p += strcspn(p, WHITESPACE);
+	p += strspn(p, WHITESPACE);
+
+	/* Skip host name */
+	p += strcspn(p, WHITESPACE);
+	p += strspn(p, WHITESPACE);
+
+	/* Cut off end of line */
+	p[strcspn(p, "\n\r\t ")] = 0;
+
+	if (inet_pton(af, p, data) <= 0)
+		goto finish;
+
+	ret = 0;
+
+finish:
+	fclose(f);
+
+	return ret;
+}
+
+int __avahi_resolve_address(int af, const void *data, char* name,
+			    size_t name_len)
+{
+	FILE *f;
+	char *p;
+	int ret = -1;
+	char a[256], ln[256];
+
+	if (af != AF_INET && af != AF_INET6)
+		return ret;
+
+	f = avahi_open_socket();
+	if (!f)
+		return ret;
+
+	fprintf(f, "RESOLVE-ADDRESS %s\n", inet_ntop(af, data, a, sizeof(a)));
+
+	if (!fgets(ln, sizeof(ln), f))
+		goto finish;
+
+	if (ln[0] != '+') {
+		ret = 1;
+		goto finish;
+	}
+
+	p = ln + 1;
+	p += strspn(p, WHITESPACE);
+
+	/* Skip interface */
+	p += strcspn(p, WHITESPACE);
+	p += strspn(p, WHITESPACE);
+
+	/* Skip protocol */
+	p += strcspn(p, WHITESPACE);
+	p += strspn(p, WHITESPACE);
+
+	/* Cut off end of line */
+	p[strcspn(p, "\n\r\t ")] = 0;
+
+	strncpy(name, p, name_len - 1);
+	name[name_len - 1] = 0;
+
+	ret = 0;
+
+finish:
+	fclose(f);
+
+	return ret;
+}
diff --git a/libc/inet/avahi.h b/libc/inet/avahi.h
new file mode 100644
index 0000000..85df5f6
--- /dev/null
+++ b/libc/inet/avahi.h
@@ -0,0 +1,33 @@
+/*
+ *
+ * (C) 2011 Weinmann GmbH, Hamburg, Germany
+ *
+ * Author: Nikolaus Voss <n.voss@weinmann.de>
+ *
+ * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
+ *
+ */
+
+#ifndef _UCLIBC_AVAHI_H_
+#define _UCLIBC_AVAHI_H_
+
+#ifdef __UCLIBC_HAS_AVAHI_RES__
+int __avahi_resolve_name(int af, const char* name, void* data) attribute_hidden;
+
+int __avahi_resolve_address(int af, const void *data, char* name,
+			    size_t name_len) attribute_hidden;
+#else
+static inline int __avahi_resolve_name(int af, const char* name, void* data)
+	attribute_hidden
+{
+	return 1;
+}
+
+static inline int __avahi_resolve_address(int af, const void *data, char* name,
+					  size_t name_len) attribute_hidden
+{
+	return 1;
+}
+#endif
+
+#endif
diff --git a/libc/inet/resolv.c b/libc/inet/resolv.c
index bc596b0..2527b50 100644
--- a/libc/inet/resolv.c
+++ b/libc/inet/resolv.c
@@ -318,6 +318,7 @@ Domain name in a message can be represented as either:
 #include <sys/stat.h>
 #include <bits/uClibc_mutex.h>
 #include "internal/parse_config.h"
+#include "avahi.h"
 
 /* poll() is not supported in kernel <= 2.0, therefore if __NR_poll is
  * not available, we assume an old Linux kernel is in use and we will
@@ -2073,10 +2074,11 @@ int gethostbyname_r(const char *name,
 	alias[0] = alias0;
 	alias[1] = NULL;
 
-	/* maybe it is already an address? */
+	/* maybe it is resolvable via avahi or already an address? */
 	{
 		struct in_addr *in = (struct in_addr *)(buf + sizeof(addr_list[0]) * 2);
-		if (inet_aton(name, in)) {
+		if (!__avahi_resolve_name(AF_INET, name, in) ||
+		    inet_aton(name, in)) {
 			addr_list[0] = in;
 			addr_list[1] = NULL;
 			result_buf->h_name = alias0;
@@ -2263,8 +2265,9 @@ int gethostbyname2_r(const char *name,
 	strncpy(buf, name, buflen);
 	buf[buflen] = '\0';
 
-	/* maybe it is already an address? */
-	if (inet_pton(AF_INET6, name, in)) {
+	/* maybe it is resolvable via avahi or already an address? */
+	if (!__avahi_resolve_name(AF_INET6, name, in) ||
+	    inet_pton(AF_INET6, name, in)) {
 		result_buf->h_name = buf;
 		result_buf->h_addrtype = AF_INET6;
 		result_buf->h_length = sizeof(*in);
@@ -2427,6 +2430,18 @@ int gethostbyaddr_r(const void *addr, socklen_t addrlen,
 	addr_list[1] = NULL;
 	memcpy(in, addr, addrlen);
 
+	/* is this a .local address? */
+	if (!__avahi_resolve_address(type, in, buf, buflen)) {
+		result_buf->h_name = buf;
+		result_buf->h_addrtype = type;
+		result_buf->h_length = addrlen;
+		result_buf->h_addr_list = (char **) addr_list;
+		result_buf->h_aliases = alias;
+		*result = result_buf;
+		*h_errnop = NETDB_SUCCESS;
+		return NETDB_SUCCESS;
+	}
+
 	if (0) /* nothing */;
 #ifdef __UCLIBC_HAS_IPV4__
 	else IF_HAS_BOTH(if (type == AF_INET)) {
diff --git a/libc/sysdeps/linux/common/bits/kernel-features.h b/libc/sysdeps/linux/common/bits/kernel-features.h
index 6bf5544..a322334 100644
--- a/libc/sysdeps/linux/common/bits/kernel-features.h
+++ b/libc/sysdeps/linux/common/bits/kernel-features.h
@@ -310,11 +310,12 @@
 #endif
 
 /* Support for various CLOEXEC and NONBLOCK flags was added for x86,
- *    x86-64, PPC, IA-64, and SPARC in 2.6.27.  */
+ *    x86-64, PPC, IA-64, ARM and SPARC in 2.6.27.  */
 #if __LINUX_KERNEL_VERSION >= 0x02061b \
     && (defined __i386__ || defined __x86_64__ || defined __powerpc__ \
-        || defined __ia64__ || defined __sparc__ || defined __s390__)
-/* # define __ASSUME_SOCK_CLOEXEC  1 */
+        || defined __ia64__ || defined __sparc__ || defined __s390__ \
+        || defined __arm__)
+# define __ASSUME_SOCK_CLOEXEC  1
 /* # define __ASSUME_IN_NONBLOCK   1 */
 # define __ASSUME_PIPE2         1
 /* # define __ASSUME_EVENTFD2      1 */
-- 
1.7.5.4