ipconfig: add nameserver IPs to kernel-parameter ip=

PATCH Superseded Christoph Fritz 3 participants 9 messages Sep 20, 2012 – Sep 25, 2012

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Christoph Fritz

author

2012-09-20 21:28 UTC #0 lore raw

PATCH 1/1 ipconfig: add nameserver IPs to kernel-parameter ip=

On small systems (e.g. embedded ones) IP addresses are often configured by bootloaders and get assigned to kernel via parameter "ip=". If set to "ip=dhcp", even nameserver entries from DHCP daemons are handled. These entries exported in /proc/net/pnp are commonly linked by /etc/resolv.conf.

To configure nameservers for networks without DHCP, this patch adds option <dns0-ip> and <dns1-ip> to kernel-parameter 'ip='.

Signed-off-by Christoph Fritz <[email protected]>

Tested-by Jan Weitzel <[email protected]>

---
 Documentation/filesystems/nfs/nfsroot.txt |    7 +++++
 net/ipv4/ipconfig.c                       |   39 ++++++++++++++++++++++++++--
 2 files changed, 43 insertions(+), 3 deletions(-)

Documentation/filesystems/nfs/nfsroot.txt +7 -0

index ffdd9d8..4ed7875 100644
@@ -158,6 +158,13 @@ ip=<client-ip>:<server-ip>:<gw-ip>:<netmask>:<hostname>:<device>:<autoconf>
 
                 Default: any
 
+  <dns0-ip>	IP address of first nameserver.
+		Value gets exported by /proc/net/pnp which is often linked
+		on embedded systems by /etc/resolv.conf.
+
+  <dns1-ip>	IP address of secound nameserver.
+		Same as above.
+
 
 nfsrootdebug

net/ipv4/ipconfig.c +36 -3

index 67e8a6b..bfbd61e 100644
@@ -743,14 +743,22 @@ static void __init ic_bootp_init_ext(u8 *e)
 
 
 /*
- *  Initialize the DHCP/BOOTP mechanism.
+ *  Predefine Nameservers
  */
-static inline void __init ic_bootp_init(void)
+static inline void __init ic_nameservers_predef(void)
 {
 	int i;
 
 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
 		ic_nameservers[i] = NONE;
+}
+
+/*
+ *  Initialize the DHCP/BOOTP mechanism.
+ */
+static inline void __init ic_bootp_init(void)
+{
+	ic_nameservers_predef();
 
 	dev_add_pack(&bootp_packet_type);
 }

@@ -1379,6 +1387,7 @@ static int __init ip_auto_config(void)
 	int retries = CONF_OPEN_RETRIES;
 #endif
 	int err;
+	unsigned int i;
 
 #ifdef CONFIG_PROC_FS
 	proc_net_fops_create(&init_net, "pnp", S_IRUGO, &pnp_seq_fops);

@@ -1499,7 +1508,15 @@ static int __init ip_auto_config(void)
 		&ic_servaddr, &root_server_addr, root_server_path);
 	if (ic_dev_mtu)
 		pr_cont(", mtu=%d", ic_dev_mtu);
-	pr_cont("\n");
+	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
+		if (ic_nameservers[i] != NONE) {
+			pr_info("     nameserver%u=%pI4",
+							i, &ic_nameservers[i]);
+			break;
+		}
+	for (i++; i < CONF_NAMESERVERS_MAX; i++)
+		if (ic_nameservers[i] != NONE)
+			pr_cont(", nameserver%u=%pI4\n", i, &ic_nameservers[i]);
 #endif /* !SILENT */
 
 	return 0;

@@ -1570,6 +1587,8 @@ static int __init ip_auto_config_setup(char *addrs)
 		return 1;
 	}
 
+	ic_nameservers_predef();
+
 	/* Parse string for static IP assignment.  */
 	ip = addrs;
 	while (ip && *ip) {

@@ -1613,6 +1632,20 @@ static int __init ip_auto_config_setup(char *addrs)
 					ic_enable = 0;
 				}
 				break;
+			case 7:
+				if (CONF_NAMESERVERS_MAX >= 1) {
+					ic_nameservers[0] = in_aton(ip);
+					if (ic_nameservers[0] == ANY)
+						ic_nameservers[0] = NONE;
+				}
+				break;
+			case 8:
+				if (CONF_NAMESERVERS_MAX >= 2) {
+					ic_nameservers[1] = in_aton(ip);
+					if (ic_nameservers[1] == ANY)
+						ic_nameservers[1] = NONE;
+				}
+				break;
 			}
 		}
 		ip = cp;

Signature · 1 line

1.7.2.5

David Miller

maintainer

2012-09-20 21:37 UTC #1 lore raw

From: Christoph Fritz <[email protected]>
Date: Thu, 20 Sep 2012 23:28:05 +0200

net/ipv4/ipconfig.c static int __init ip_auto_config(void) · line 1514

Quoted 2 lines

net/ipv4/ipconfig.c +2 -0

+			pr_info("     nameserver%u=%pI4",
+							i, &ic_nameservers[i]);

Why don't you just tab that second line out to planet Mars while you're at it?

Please format this correctly, the goal is not to use a million TAB characters. Rather, the goal is to get the text starting on the second line of a function call to line up with the first column after the openning parenthesis on the previous line.

What you're doing there looks awful, so you'll need to fix this up before this patch will be considered seriously.

Thanks.

Christoph Fritz

author

2012-09-20 21:48 UTC #2 lore raw

PATCH v2 1/1 ipconfig: add nameserver IPs to kernel-parameter ip=

To configure nameservers for networks without DHCP, this patch adds option <dns0-ip> and <dns1-ip> to kernel-parameter 'ip='.

Signed-off-by Christoph Fritz <[email protected]>

Tested-by Jan Weitzel <[email protected]>

---
v2: - fix indent

---
 Documentation/filesystems/nfs/nfsroot.txt |    7 +++++
 net/ipv4/ipconfig.c                       |   39 ++++++++++++++++++++++++++--
 2 files changed, 43 insertions(+), 3 deletions(-)

Documentation/filesystems/nfs/nfsroot.txt +7 -0

index ffdd9d8..4ed7875 100644
@@ -158,6 +158,13 @@ ip=<client-ip>:<server-ip>:<gw-ip>:<netmask>:<hostname>:<device>:<autoconf>
 
                 Default: any
 
+  <dns0-ip>	IP address of first nameserver.
+		Value gets exported by /proc/net/pnp which is often linked
+		on embedded systems by /etc/resolv.conf.
+
+  <dns1-ip>	IP address of secound nameserver.
+		Same as above.
+
 
 nfsrootdebug

net/ipv4/ipconfig.c +36 -3

index 67e8a6b..1c0e7e0 100644
@@ -743,14 +743,22 @@ static void __init ic_bootp_init_ext(u8 *e)
 
 
 /*
- *  Initialize the DHCP/BOOTP mechanism.
+ *  Predefine Nameservers
  */
-static inline void __init ic_bootp_init(void)
+static inline void __init ic_nameservers_predef(void)
 {
 	int i;
 
 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
 		ic_nameservers[i] = NONE;
+}
+
+/*
+ *  Initialize the DHCP/BOOTP mechanism.
+ */
+static inline void __init ic_bootp_init(void)
+{
+	ic_nameservers_predef();
 
 	dev_add_pack(&bootp_packet_type);
 }

@@ -1379,6 +1387,7 @@ static int __init ip_auto_config(void)
 	int retries = CONF_OPEN_RETRIES;
 #endif
 	int err;
+	unsigned int i;
 
 #ifdef CONFIG_PROC_FS
 	proc_net_fops_create(&init_net, "pnp", S_IRUGO, &pnp_seq_fops);

@@ -1499,7 +1508,15 @@ static int __init ip_auto_config(void)
 		&ic_servaddr, &root_server_addr, root_server_path);
 	if (ic_dev_mtu)
 		pr_cont(", mtu=%d", ic_dev_mtu);
-	pr_cont("\n");
+	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
+		if (ic_nameservers[i] != NONE) {
+			pr_info("     nameserver%u=%pI4",
+				i, &ic_nameservers[i]);
+			break;
+		}
+	for (i++; i < CONF_NAMESERVERS_MAX; i++)
+		if (ic_nameservers[i] != NONE)
+			pr_cont(", nameserver%u=%pI4\n", i, &ic_nameservers[i]);
 #endif /* !SILENT */
 
 	return 0;

@@ -1570,6 +1587,8 @@ static int __init ip_auto_config_setup(char *addrs)
 		return 1;
 	}
 
+	ic_nameservers_predef();
+
 	/* Parse string for static IP assignment.  */
 	ip = addrs;
 	while (ip && *ip) {

@@ -1613,6 +1632,20 @@ static int __init ip_auto_config_setup(char *addrs)
 					ic_enable = 0;
 				}
 				break;
+			case 7:
+				if (CONF_NAMESERVERS_MAX >= 1) {
+					ic_nameservers[0] = in_aton(ip);
+					if (ic_nameservers[0] == ANY)
+						ic_nameservers[0] = NONE;
+				}
+				break;
+			case 8:
+				if (CONF_NAMESERVERS_MAX >= 2) {
+					ic_nameservers[1] = in_aton(ip);
+					if (ic_nameservers[1] == ANY)
+						ic_nameservers[1] = NONE;
+				}
+				break;
 			}
 		}
 		ip = cp;

Signature · 1 line

1.7.2.5

David Miller

maintainer

2012-09-21 17:37 UTC #3 lore raw

From: Christoph Fritz <[email protected]>
Date: Thu, 20 Sep 2012 23:48:50 +0200

Quoted 8 lines

Documentation/filesystems/nfs/nfsroot.txt +0 -0

index ffdd9d8..4ed7875 100644
@@ -158,6 +158,13 @@ ip=<client-ip>:<server-ip>:<gw-ip>:<netmask>:<hostname>:<device>:<autoconf>
 
                 Default: any

Documentation/filesystems/nfs/nfsroot.txt ip=<client-ip>:<server-ip>:<gw-ip>:<netmask>:<hostname>:<device>:<autoconf> · line 170

Quoted 10 lines

Documentation/filesystems/nfs/nfsroot.txt +7 -0

+  <dns0-ip>	IP address of first nameserver.
+		Value gets exported by /proc/net/pnp which is often linked
+		on embedded systems by /etc/resolv.conf.
+
+  <dns1-ip>	IP address of secound nameserver.
+		Same as above.
+
 
 nfsrootdebug

This documentation update is not sufficient.

You have to properly show, in the lines above where you made your change, where the new settings are placed in the "ip=" option.

Christoph Fritz

author

2012-09-21 18:31 UTC #4 lore raw

PATCH v3 1/1 ipconfig: add nameserver IPs to kernel-parameter ip=

To configure nameservers for networks without DHCP, this patch adds option <dns0-ip> and <dns1-ip> to kernel-parameter 'ip='.

Signed-off-by Christoph Fritz <[email protected]>

Tested-by Jan Weitzel <[email protected]>

---
v2: - fix indent
v3: - fix docu: add new arguments to option "ip="

---
 Documentation/filesystems/nfs/nfsroot.txt |   10 ++++++-
 net/ipv4/ipconfig.c                       |   39 ++++++++++++++++++++++++++--
 2 files changed, 45 insertions(+), 4 deletions(-)

Documentation/filesystems/nfs/nfsroot.txt +9 -1

index ffdd9d8..2d66ed6 100644
@@ -78,7 +78,8 @@ nfsroot=[<server-ip>:]<root-dir>[,<nfs-options>]
 			flags		= hard, nointr, noposix, cto, ac
 
 
-ip=<client-ip>:<server-ip>:<gw-ip>:<netmask>:<hostname>:<device>:<autoconf>
+ip=<client-ip>:<server-ip>:<gw-ip>:<netmask>:<hostname>:<device>:<autoconf>:
+   <dns0-ip>:<dns1-ip>
 
   This parameter tells the kernel how to configure IP addresses of devices
   and also how to set up the IP routing table. It was originally called

@@ -158,6 +159,13 @@ ip=<client-ip>:<server-ip>:<gw-ip>:<netmask>:<hostname>:<device>:<autoconf>
 
                 Default: any
 
+  <dns0-ip>	IP address of first nameserver.
+		Value gets exported by /proc/net/pnp which is often linked
+		on embedded systems by /etc/resolv.conf.
+
+  <dns1-ip>	IP address of secound nameserver.
+		Same as above.
+
 
 nfsrootdebug

net/ipv4/ipconfig.c +36 -3

index 67e8a6b..1c0e7e0 100644
@@ -743,14 +743,22 @@ static void __init ic_bootp_init_ext(u8 *e)
 
 
 /*
- *  Initialize the DHCP/BOOTP mechanism.
+ *  Predefine Nameservers
  */
-static inline void __init ic_bootp_init(void)
+static inline void __init ic_nameservers_predef(void)
 {
 	int i;
 
 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
 		ic_nameservers[i] = NONE;
+}
+
+/*
+ *  Initialize the DHCP/BOOTP mechanism.
+ */
+static inline void __init ic_bootp_init(void)
+{
+	ic_nameservers_predef();
 
 	dev_add_pack(&bootp_packet_type);
 }

@@ -1379,6 +1387,7 @@ static int __init ip_auto_config(void)
 	int retries = CONF_OPEN_RETRIES;
 #endif
 	int err;
+	unsigned int i;
 
 #ifdef CONFIG_PROC_FS
 	proc_net_fops_create(&init_net, "pnp", S_IRUGO, &pnp_seq_fops);

@@ -1499,7 +1508,15 @@ static int __init ip_auto_config(void)
 		&ic_servaddr, &root_server_addr, root_server_path);
 	if (ic_dev_mtu)
 		pr_cont(", mtu=%d", ic_dev_mtu);
-	pr_cont("\n");
+	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
+		if (ic_nameservers[i] != NONE) {
+			pr_info("     nameserver%u=%pI4",
+				i, &ic_nameservers[i]);
+			break;
+		}
+	for (i++; i < CONF_NAMESERVERS_MAX; i++)
+		if (ic_nameservers[i] != NONE)
+			pr_cont(", nameserver%u=%pI4\n", i, &ic_nameservers[i]);
 #endif /* !SILENT */
 
 	return 0;

@@ -1570,6 +1587,8 @@ static int __init ip_auto_config_setup(char *addrs)
 		return 1;
 	}
 
+	ic_nameservers_predef();
+
 	/* Parse string for static IP assignment.  */
 	ip = addrs;
 	while (ip && *ip) {

@@ -1613,6 +1632,20 @@ static int __init ip_auto_config_setup(char *addrs)
 					ic_enable = 0;
 				}
 				break;
+			case 7:
+				if (CONF_NAMESERVERS_MAX >= 1) {
+					ic_nameservers[0] = in_aton(ip);
+					if (ic_nameservers[0] == ANY)
+						ic_nameservers[0] = NONE;
+				}
+				break;
+			case 8:
+				if (CONF_NAMESERVERS_MAX >= 2) {
+					ic_nameservers[1] = in_aton(ip);
+					if (ic_nameservers[1] == ANY)
+						ic_nameservers[1] = NONE;
+				}
+				break;
 			}
 		}
 		ip = cp;

Signature · 1 line

1.7.2.5

David Miller

maintainer Applied

2012-09-21 18:51 UTC #5 lore raw

From: Christoph Fritz <[email protected]>
Date: Fri, 21 Sep 2012 20:31:19 +0200

Quoted 10 lines

On small systems (e.g. embedded ones) IP addresses are often configured by bootloaders and get assigned to kernel via parameter "ip=". If set to "ip=dhcp", even nameserver entries from DHCP daemons are handled. These entries exported in /proc/net/pnp are commonly linked by /etc/resolv.conf.
To configure nameservers for networks without DHCP, this patch adds option <dns0-ip> and <dns1-ip> to kernel-parameter 'ip='.
Signed-off-by Christoph Fritz <[email protected]>
Tested-by Jan Weitzel <[email protected]>

Applied to net-next, thanks.

Christoph Fritz

author

2012-09-21 19:28 UTC #6 lore raw

Quoted 8 lines · David Miller

From: Christoph Fritz <[email protected]>
Date: Fri, 21 Sep 2012 20:31:19 +0200
Quoted 5 lines
On small systems (e.g. embedded ones) IP addresses are often configured by bootloaders and get assigned to kernel via parameter "ip=". If set to "ip=dhcp", even nameserver entries from DHCP daemons are handled. These entries exported in /proc/net/pnp are commonly linked by /etc/resolv.conf.

Quoted 7 lines

Quoted 5 lines
To configure nameservers for networks without DHCP, this patch adds option <dns0-ip> and <dns1-ip> to kernel-parameter 'ip='.
Signed-off-by Christoph Fritz <[email protected]>
Tested-by Jan Weitzel <[email protected]>
Applied to net-next, thanks.

Thanks a lot for your reviews.

-- Christoph

Andy Shevchenko

2012-09-25 08:09 UTC #7 lore raw

PATCH 1/1 ipconfig: fix trivial build error

The commit 5e953778a2aab04929a5e7b69f53dc26e39b079e ("ipconfig: add nameserver IPs to kernel-parameter ip=") introduces ic_nameservers_predef() that defined only for BOOTP. However it is used by ip_auto_config_setup() as well. This patch moves it outside of #ifdef BOOTP.

Signed-off-by Andy Shevchenko <[email protected]>

Cc Christoph Fritz <[email protected]>

Cc David S. Miller <[email protected]>

---
 net/ipv4/ipconfig.c |   22 +++++++++++-----------
 1 file changed, 11 insertions(+), 11 deletions(-)

net/ipv4/ipconfig.c +11 ~~-11~~

index 1c0e7e0..798358b 100644
@@ -583,6 +583,17 @@ static void __init ic_rarp_send_if(struct ic_device *d)
 #endif
 
 /*
+ *  Predefine Nameservers
+ */
+static inline void __init ic_nameservers_predef(void)
+{
+	int i;
+
+	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
+		ic_nameservers[i] = NONE;
+}
+
+/*
  *	DHCP/BOOTP support.
  */

@@ -743,17 +754,6 @@ static void __init ic_bootp_init_ext(u8 *e)
 
 
 /*
- *  Predefine Nameservers
- */
-static inline void __init ic_nameservers_predef(void)
-{
-	int i;
-
-	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
-		ic_nameservers[i] = NONE;
-}
-
-/*
  *  Initialize the DHCP/BOOTP mechanism.
  */
 static inline void __init ic_bootp_init(void)

Signature · 1 line

1.7.10.4

David Miller

maintainer Applied

2012-09-25 17:23 UTC #8 lore raw

Re: [PATCH] ipconfig: fix trivial build error

From: Andy Shevchenko <[email protected]>
Date: Tue, 25 Sep 2012 11:09:58 +0300

Quoted 6 lines

The commit 5e953778a2aab04929a5e7b69f53dc26e39b079e ("ipconfig: add nameserver IPs to kernel-parameter ip=") introduces ic_nameservers_predef() that defined only for BOOTP. However it is used by ip_auto_config_setup() as well. This patch moves it outside of #ifdef BOOTP.
Signed-off-by Andy Shevchenko <[email protected]>

Applied, thanks.