Add getdnsconfig(2) and setdnsconfig(2).

kernel/Makefile

@@ -91,6 +91,7 @@ disk/ata/ata.o \
 disk/ata/hba.o \
 disk/ata/port.o \
 disk/node.o \
+dnsconfig.o \
 dtable.o \
 elf.o \
 fcache.o \

kernel/dnsconfig.cpp

@@ -0,0 +1,77 @@
+/*
+ * Copyright (c) 2016 Jonas 'Sortie' Termansen.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ * dnsconfig.cpp
+ * System calls for managing the dns configuration of the current system.
+ */
+
+#include <sys/dnsconfig.h>
+
+#include <errno.h>
+#include <string.h>
+
+#include <sortix/kernel/copy.h>
+#include <sortix/kernel/kernel.h>
+#include <sortix/kernel/kthread.h>
+#include <sortix/kernel/syscall.h>
+
+namespace Sortix {
+
+static kthread_mutex_t dnsconfig_lock = KTHREAD_MUTEX_INITIALIZER;
+static struct dnsconfig dnsconfig;
+
+int sys_getdnsconfig(struct dnsconfig* user_cfg)
+{
+	ScopedLock lock(&dnsconfig_lock);
+	if ( !CopyToUser(user_cfg, &dnsconfig, sizeof(dnsconfig)) )
+		return -1;
+	return 0;
+}
+
+int sys_setdnsconfig(const struct dnsconfig* user_cfg)
+{
+	ScopedLock lock(&dnsconfig_lock);
+	struct dnsconfig newcfg;
+	if ( !CopyFromUser(&newcfg, user_cfg, sizeof(dnsconfig)) )
+		return -1;
+	if ( DNSCONFIG_MAX_SERVERS < newcfg.servers_count )
+		return errno = EINVAL, -1;
+	for ( size_t i = 0; i < newcfg.servers_count; i++ )
+	{
+		struct dnsconfig_server* server = &newcfg.servers[i];
+		if ( server->family == AF_INET )
+		{
+			if ( server->addrsize != sizeof(struct in_addr) )
+				return errno = EINVAL, -1;
+			memset(&server->addr.in + 1, 0,
+			       sizeof(server->addr) - sizeof(server->addr.in));
+		}
+		else if ( server->family == AF_INET6 )
+		{
+			if ( server->addrsize != sizeof(struct in6_addr) )
+				return errno = EINVAL, -1;
+			memset(&server->addr.in6 + 1, 0,
+			       sizeof(server->addr) - sizeof(server->addr.in6));
+		}
+		else
+			return errno = EAFNOSUPPORT, -1;
+	}
+	for ( size_t i = newcfg.servers_count; i < DNSCONFIG_MAX_SERVERS; i++ )
+		memset(&newcfg.servers[i], 0, sizeof(newcfg.servers[i]));
+	memcpy(&dnsconfig, &newcfg, sizeof(dnsconfig));
+	return 0;
+}
+
+} // namespace Sortix

kernel/include/sortix/kernel/syscall.h

@@ -20,6 +20,7 @@
 #ifndef INCLUDE_SORTIX_KERNEL_SYSCALL_H
 #define INCLUDE_SORTIX_KERNEL_SYSCALL_H
 
+#include <sys/dnsconfig.h>
 #include <sys/socket.h>
 #include <sys/types.h>
 
@@ -89,6 +90,7 @@ int sys_fstatvfsat(int, const char*, struct statvfs*, int);
 int sys_fsync(int);
 int sys_ftruncate(int, off_t);
 int sys_futimens(int, const struct timespec*);
+int sys_getdnsconfig(struct dnsconfig*);
 gid_t sys_getegid(void);
 int sys_getentropy(void*, size_t);
 uid_t sys_geteuid(void);
@@ -142,6 +144,7 @@ void sys_scram(int, const void*);
 int sys_sched_yield(void);
 ssize_t sys_send(int, const void*, size_t, int);
 ssize_t sys_sendmsg(int, const struct msghdr*, int);
+int sys_setdnsconfig(const struct dnsconfig*);
 int sys_setegid(gid_t);
 int sys_seteuid(uid_t);
 int sys_setgid(gid_t);

kernel/include/sortix/syscall.h

@@ -186,6 +186,8 @@
 #define SYSCALL_GETSID 163
 #define SYSCALL_SETSID 164
 #define SYSCALL_SOCKET 165
-#define SYSCALL_MAX_NUM 166 /* index of highest constant + 1 */
+#define SYSCALL_GETDNSCONFIG 166
+#define SYSCALL_SETDNSCONFIG 167
+#define SYSCALL_MAX_NUM 168 /* index of highest constant + 1 */
 
 #endif

kernel/syscall.cpp

@@ -200,6 +200,8 @@ void* syscall_list[SYSCALL_MAX_NUM + 1] =
 	[SYSCALL_GETSID] = (void*) sys_getsid,
 	[SYSCALL_SETSID] = (void*) sys_setsid,
 	[SYSCALL_SOCKET] = (void*) sys_socket,
+	[SYSCALL_GETDNSCONFIG] = (void*) sys_getdnsconfig,
+	[SYSCALL_SETDNSCONFIG] = (void*) sys_setdnsconfig,
 	[SYSCALL_MAX_NUM] = (void*) sys_bad_syscall,
 };
 } /* extern "C" */

libc/Makefile

@@ -555,6 +555,8 @@ stdlib/system.o \
 stdlib/unlockpt.o \
 stdlib/unsetenv.o \
 sys/display/dispmsg_issue.o \
+sys/dnsconfig/getdnsconfig.o \
+sys/dnsconfig/setdnsconfig.o \
 sys/ioctl/ioctl.o \
 sys/kernelinfo/kernelinfo.o \
 syslog/closelog.o \

libc/include/sys/dnsconfig.h

@@ -0,0 +1,60 @@
+/*
+ * Copyright (c) 2016 Jonas 'Sortie' Termansen.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ * sys/dnsconfig.h
+ * Domain name system configuration.
+ */
+
+#ifndef INCLUDE_SYS_DNSCONFIG_H
+#define INCLUDE_SYS_DNSCONFIG_H
+
+#include <sys/cdefs.h>
+
+#include <netinet/in.h>
+#include <stddef.h>
+
+union dnsconfig_server_union
+{
+	struct in_addr in;
+	struct in6_addr in6;
+};
+
+struct dnsconfig_server
+{
+	sa_family_t family;
+	size_t addrsize;
+	union dnsconfig_server_union addr;
+};
+
+#define DNSCONFIG_MAX_SERVERS 3
+
+struct dnsconfig
+{
+	size_t servers_count;
+	struct dnsconfig_server servers[DNSCONFIG_MAX_SERVERS];
+};
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+int getdnsconfig(struct dnsconfig*);
+int setdnsconfig(const struct dnsconfig*);
+
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
+
+#endif

libc/sys/dnsconfig/getdnsconfig.c

@@ -0,0 +1,28 @@
+/*
+ * Copyright (c) 2016 Jonas 'Sortie' Termansen.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ * sys/dnsconfig/getdnsconfig.c
+ * Get the domain name system configuration.
+ */
+
+#include <sys/dnsconfig.h>
+#include <sys/syscall.h>
+
+DEFN_SYSCALL1(int, sys_getdnsconfig, SYSCALL_GETDNSCONFIG, struct dnsconfig*);
+
+int getdnsconfig(struct dnsconfig* cfg)
+{
+	return sys_getdnsconfig(cfg);
+}

libc/sys/dnsconfig/setdnsconfig.c

@@ -0,0 +1,28 @@
+/*
+ * Copyright (c) 2016 Jonas 'Sortie' Termansen.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ * sys/dnsconfig/setdnsconfig.c
+ * Set the domain name system configuration.
+ */
+
+#include <sys/dnsconfig.h>
+#include <sys/syscall.h>
+
+DEFN_SYSCALL1(int, sys_setdnsconfig, SYSCALL_SETDNSCONFIG, const struct dnsconfig*);
+
+int setdnsconfig(const struct dnsconfig* cfg)
+{
+	return sys_setdnsconfig(cfg);
+}