diff mbox series

[nf-next] nft_osf: Add ttl option support

Message ID 20180916191016.1100-1-ffmancera@riseup.net
State Changes Requested
Delegated to: Pablo Neira
Headers show
Series [nf-next] nft_osf: Add ttl option support | expand

Commit Message

Fernando F. Mancera Sept. 16, 2018, 7:10 p.m. UTC 
Add ttl option support to the nftables "osf" expression.

Signed-off-by: Fernando Fernandez Mancera <ffmancera@riseup.net>
---
 include/linux/netfilter/nfnetlink_osf.h      |  3 ++-
 include/uapi/linux/netfilter/nf_tables.h     |  7 +++++++
 include/uapi/linux/netfilter/nfnetlink_osf.h |  1 +
 net/netfilter/nfnetlink_osf.c                |  5 +++--
 net/netfilter/nft_osf.c                      | 14 +++++++++++++-
 5 files changed, 26 insertions(+), 4 deletions(-)

Comments

Pablo Neira Ayuso Sept. 17, 2018, 11:15 p.m. UTC | #1 
On Sun, Sep 16, 2018 at 09:10:16PM +0200, Fernando Fernandez Mancera wrote:
> Add ttl option support to the nftables "osf" expression.
> 
> Signed-off-by: Fernando Fernandez Mancera <ffmancera@riseup.net>
> ---
>  include/linux/netfilter/nfnetlink_osf.h      |  3 ++-
>  include/uapi/linux/netfilter/nf_tables.h     |  7 +++++++
>  include/uapi/linux/netfilter/nfnetlink_osf.h |  1 +
>  net/netfilter/nfnetlink_osf.c                |  5 +++--
>  net/netfilter/nft_osf.c                      | 14 +++++++++++++-
>  5 files changed, 26 insertions(+), 4 deletions(-)
> 
> diff --git a/include/linux/netfilter/nfnetlink_osf.h b/include/linux/netfilter/nfnetlink_osf.h
> index ecf7dab81e9e..c6000046c966 100644
> --- a/include/linux/netfilter/nfnetlink_osf.h
> +++ b/include/linux/netfilter/nfnetlink_osf.h
> @@ -27,6 +27,7 @@ bool nf_osf_match(const struct sk_buff *skb, u_int8_t family,
>  		  const struct list_head *nf_osf_fingers);
>  
>  const char *nf_osf_find(const struct sk_buff *skb,
> -                        const struct list_head *nf_osf_fingers);
> +			const struct list_head *nf_osf_fingers,
> +			const int ttl_check);
>  
>  #endif /* _NFOSF_H */
> diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h
> index e23290ffdc77..85df36521153 100644
> --- a/include/uapi/linux/netfilter/nf_tables.h
> +++ b/include/uapi/linux/netfilter/nf_tables.h
> @@ -1493,9 +1493,16 @@ enum nft_flowtable_hook_attributes {
>  };
>  #define NFTA_FLOWTABLE_HOOK_MAX	(__NFTA_FLOWTABLE_HOOK_MAX - 1)
>  
> +/**
> + * enum nft_osf_attributes - nftables osf expression netlink attributes
> + *
> + * @NFTA_OSF_DREG: destination register (NLA_U32: nft_registers)
> + * @NFTA_OSF_TTL: Value of the TTL osf option (NLA_U8)
> + */
>  enum nft_osf_attributes {
>  	NFTA_OSF_UNSPEC,
>  	NFTA_OSF_DREG,
> +	NFTA_OSF_TTL,
>  	__NFTA_OSF_MAX,
>  };
>  #define NFTA_OSF_MAX (__NFTA_OSF_MAX - 1)
> diff --git a/include/uapi/linux/netfilter/nfnetlink_osf.h b/include/uapi/linux/netfilter/nfnetlink_osf.h
> index 272bc3195f2d..7e0c00658bf8 100644
> --- a/include/uapi/linux/netfilter/nfnetlink_osf.h
> +++ b/include/uapi/linux/netfilter/nfnetlink_osf.h
> @@ -26,6 +26,7 @@
>  
>  #define NF_OSF_FLAGMASK		(NF_OSF_GENRE | NF_OSF_TTL | \
>  				 NF_OSF_LOG | NF_OSF_INVERT)
> +

You can remove this entire patch chunk. This newline is not needed.

>  /* Wildcard MSS (kind of).
>   * It is used to implement a state machine for the different wildcard values
>   * of the MSS and window sizes.
> diff --git a/net/netfilter/nfnetlink_osf.c b/net/netfilter/nfnetlink_osf.c
> index 00db27dfd2ff..ec8fa9661538 100644
> --- a/net/netfilter/nfnetlink_osf.c
> +++ b/net/netfilter/nfnetlink_osf.c
> @@ -257,7 +257,8 @@ nf_osf_match(const struct sk_buff *skb, u_int8_t family,
>  EXPORT_SYMBOL_GPL(nf_osf_match);
>  
>  const char *nf_osf_find(const struct sk_buff *skb,
> -			const struct list_head *nf_osf_fingers)
> +			const struct list_head *nf_osf_fingers,
> +			const int ttl_check)
>  {
>  	const struct iphdr *ip = ip_hdr(skb);
>  	const struct nf_osf_user_finger *f;
> @@ -275,7 +276,7 @@ const char *nf_osf_find(const struct sk_buff *skb,
>  
>  	list_for_each_entry_rcu(kf, &nf_osf_fingers[ctx.df], finger_entry) {
>  		f = &kf->finger;
> -		if (!nf_osf_match_one(skb, f, -1, &ctx))
> +		if (!nf_osf_match_one(skb, f, ttl_check, &ctx))
>  			continue;
>  
>  		genre = f->genre;
> diff --git a/net/netfilter/nft_osf.c b/net/netfilter/nft_osf.c
> index 5af74b37f423..b63c5f5c716b 100644
> --- a/net/netfilter/nft_osf.c
> +++ b/net/netfilter/nft_osf.c
> @@ -6,10 +6,12 @@
>  
>  struct nft_osf {
>  	enum nft_registers	dreg:8;
> +	u8			ttl;
>  };
>  
>  static const struct nla_policy nft_osf_policy[NFTA_OSF_MAX + 1] = {
>  	[NFTA_OSF_DREG]		= { .type = NLA_U32 },
> +	[NFTA_OSF_TTL]		= { .type = NLA_U8 },
>  };
>  
>  static void nft_osf_eval(const struct nft_expr *expr, struct nft_regs *regs,
> @@ -21,6 +23,7 @@ static void nft_osf_eval(const struct nft_expr *expr, struct nft_regs *regs,
>  	const struct tcphdr *tcp;
>  	struct tcphdr _tcph;
>  	const char *os_name;
> +	int ttl_check;
>  
>  	tcp = skb_header_pointer(skb, ip_hdrlen(skb),
>  				 sizeof(struct tcphdr), &_tcph);
> @@ -33,7 +36,8 @@ static void nft_osf_eval(const struct nft_expr *expr, struct nft_regs *regs,
>  		return;
>  	}
>  
> -	os_name = nf_osf_find(skb, nf_osf_fingers);
> +	ttl_check = priv->ttl;
> +	os_name = nf_osf_find(skb, nf_osf_fingers, ttl_check);
>  	if (!os_name)
>  		strncpy((char *)dest, "unknown", NFT_OSF_MAXGENRELEN);
>  	else
> @@ -47,6 +51,11 @@ static int nft_osf_init(const struct nft_ctx *ctx,
>  	struct nft_osf *priv = nft_expr_priv(expr);
>  	int err;
>  
> +	if (!tb[NFTA_OSF_TTL] || nla_get_u8(tb[NFTA_OSF_TTL]) < 0 ||
> +	    nla_get_u8(tb[NFTA_OSF_TTL]) > 2)

Better:

        u8 ttl;

	if (!tb[NFTA_OSF_TTL]) {
                ttl = nla_get_u8(tb[NFTA_OSF_TTL]);
                if (ttl > 2)
                        return -EOPNOTSUPP;
        }

> +		return ~EINVAL;
                       ^
                This is not a minus :-).

> +	priv->ttl = nla_get_u8(tb[NFTA_OSF_TTL]);
> +
>  	priv->dreg = nft_parse_register(tb[NFTA_OSF_DREG]);
>  	err = nft_validate_register_store(ctx, priv->dreg, NULL,
>  					  NFTA_DATA_VALUE, NFT_OSF_MAXGENRELEN);
> @@ -60,6 +69,9 @@ static int nft_osf_dump(struct sk_buff *skb, const struct nft_expr *expr)
>  {
>  	const struct nft_osf *priv = nft_expr_priv(expr);
>  
> +	if (nla_put_u8(skb, NFTA_OSF_TTL, priv->ttl))
> +		goto nla_put_failure;
> +
>  	if (nft_dump_register(skb, NFTA_OSF_DREG, priv->dreg))
>  		goto nla_put_failure;
>  
> -- 
> 2.18.0
>
Fernando F. Mancera Sept. 18, 2018, 8:13 a.m. UTC | #2 
On 9/18/18 1:15 AM, Pablo Neira Ayuso wrote:
> On Sun, Sep 16, 2018 at 09:10:16PM +0200, Fernando Fernandez Mancera wrote:
>> Add ttl option support to the nftables "osf" expression.
>>
>> Signed-off-by: Fernando Fernandez Mancera <ffmancera@riseup.net>
>> ---
>>   include/linux/netfilter/nfnetlink_osf.h      |  3 ++-
>>   include/uapi/linux/netfilter/nf_tables.h     |  7 +++++++
>>   include/uapi/linux/netfilter/nfnetlink_osf.h |  1 +
>>   net/netfilter/nfnetlink_osf.c                |  5 +++--
>>   net/netfilter/nft_osf.c                      | 14 +++++++++++++-
>>   5 files changed, 26 insertions(+), 4 deletions(-)
>>
>> diff --git a/include/linux/netfilter/nfnetlink_osf.h b/include/linux/netfilter/nfnetlink_osf.h
>> index ecf7dab81e9e..c6000046c966 100644
>> --- a/include/linux/netfilter/nfnetlink_osf.h
>> +++ b/include/linux/netfilter/nfnetlink_osf.h
>> @@ -27,6 +27,7 @@ bool nf_osf_match(const struct sk_buff *skb, u_int8_t family,
>>   		  const struct list_head *nf_osf_fingers);
>>   
>>   const char *nf_osf_find(const struct sk_buff *skb,
>> -                        const struct list_head *nf_osf_fingers);
>> +			const struct list_head *nf_osf_fingers,
>> +			const int ttl_check);
>>   
>>   #endif /* _NFOSF_H */
>> diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h
>> index e23290ffdc77..85df36521153 100644
>> --- a/include/uapi/linux/netfilter/nf_tables.h
>> +++ b/include/uapi/linux/netfilter/nf_tables.h
>> @@ -1493,9 +1493,16 @@ enum nft_flowtable_hook_attributes {
>>   };
>>   #define NFTA_FLOWTABLE_HOOK_MAX	(__NFTA_FLOWTABLE_HOOK_MAX - 1)
>>   
>> +/**
>> + * enum nft_osf_attributes - nftables osf expression netlink attributes
>> + *
>> + * @NFTA_OSF_DREG: destination register (NLA_U32: nft_registers)
>> + * @NFTA_OSF_TTL: Value of the TTL osf option (NLA_U8)
>> + */
>>   enum nft_osf_attributes {
>>   	NFTA_OSF_UNSPEC,
>>   	NFTA_OSF_DREG,
>> +	NFTA_OSF_TTL,
>>   	__NFTA_OSF_MAX,
>>   };
>>   #define NFTA_OSF_MAX (__NFTA_OSF_MAX - 1)
>> diff --git a/include/uapi/linux/netfilter/nfnetlink_osf.h b/include/uapi/linux/netfilter/nfnetlink_osf.h
>> index 272bc3195f2d..7e0c00658bf8 100644
>> --- a/include/uapi/linux/netfilter/nfnetlink_osf.h
>> +++ b/include/uapi/linux/netfilter/nfnetlink_osf.h
>> @@ -26,6 +26,7 @@
>>   
>>   #define NF_OSF_FLAGMASK		(NF_OSF_GENRE | NF_OSF_TTL | \
>>   				 NF_OSF_LOG | NF_OSF_INVERT)
>> +
> 
> You can remove this entire patch chunk. This newline is not needed >
>>   /* Wildcard MSS (kind of).
>>    * It is used to implement a state machine for the different wildcard values
>>    * of the MSS and window sizes.
>> diff --git a/net/netfilter/nfnetlink_osf.c b/net/netfilter/nfnetlink_osf.c
>> index 00db27dfd2ff..ec8fa9661538 100644
>> --- a/net/netfilter/nfnetlink_osf.c
>> +++ b/net/netfilter/nfnetlink_osf.c
>> @@ -257,7 +257,8 @@ nf_osf_match(const struct sk_buff *skb, u_int8_t family,
>>   EXPORT_SYMBOL_GPL(nf_osf_match);
>>   
>>   const char *nf_osf_find(const struct sk_buff *skb,
>> -			const struct list_head *nf_osf_fingers)
>> +			const struct list_head *nf_osf_fingers,
>> +			const int ttl_check)
>>   {
>>   	const struct iphdr *ip = ip_hdr(skb);
>>   	const struct nf_osf_user_finger *f;
>> @@ -275,7 +276,7 @@ const char *nf_osf_find(const struct sk_buff *skb,
>>   
>>   	list_for_each_entry_rcu(kf, &nf_osf_fingers[ctx.df], finger_entry) {
>>   		f = &kf->finger;
>> -		if (!nf_osf_match_one(skb, f, -1, &ctx))
>> +		if (!nf_osf_match_one(skb, f, ttl_check, &ctx))
>>   			continue;
>>   
>>   		genre = f->genre;
>> diff --git a/net/netfilter/nft_osf.c b/net/netfilter/nft_osf.c
>> index 5af74b37f423..b63c5f5c716b 100644
>> --- a/net/netfilter/nft_osf.c
>> +++ b/net/netfilter/nft_osf.c
>> @@ -6,10 +6,12 @@
>>   
>>   struct nft_osf {
>>   	enum nft_registers	dreg:8;
>> +	u8			ttl;
>>   };
>>   
>>   static const struct nla_policy nft_osf_policy[NFTA_OSF_MAX + 1] = {
>>   	[NFTA_OSF_DREG]		= { .type = NLA_U32 },
>> +	[NFTA_OSF_TTL]		= { .type = NLA_U8 },
>>   };
>>   
>>   static void nft_osf_eval(const struct nft_expr *expr, struct nft_regs *regs,
>> @@ -21,6 +23,7 @@ static void nft_osf_eval(const struct nft_expr *expr, struct nft_regs *regs,
>>   	const struct tcphdr *tcp;
>>   	struct tcphdr _tcph;
>>   	const char *os_name;
>> +	int ttl_check;
>>   
>>   	tcp = skb_header_pointer(skb, ip_hdrlen(skb),
>>   				 sizeof(struct tcphdr), &_tcph);
>> @@ -33,7 +36,8 @@ static void nft_osf_eval(const struct nft_expr *expr, struct nft_regs *regs,
>>   		return;
>>   	}
>>   
>> -	os_name = nf_osf_find(skb, nf_osf_fingers);
>> +	ttl_check = priv->ttl;
>> +	os_name = nf_osf_find(skb, nf_osf_fingers, ttl_check);
>>   	if (!os_name)
>>   		strncpy((char *)dest, "unknown", NFT_OSF_MAXGENRELEN);
>>   	else
>> @@ -47,6 +51,11 @@ static int nft_osf_init(const struct nft_ctx *ctx,
>>   	struct nft_osf *priv = nft_expr_priv(expr);
>>   	int err;
>>   
>> +	if (!tb[NFTA_OSF_TTL] || nla_get_u8(tb[NFTA_OSF_TTL]) < 0 ||
>> +	    nla_get_u8(tb[NFTA_OSF_TTL]) > 2)
> 
> Better:
> 
>          u8 ttl;
> 
> 	if (!tb[NFTA_OSF_TTL]) {
>                  ttl = nla_get_u8(tb[NFTA_OSF_TTL]);
>                  if (ttl > 2)
>                          return -EOPNOTSUPP;
>          }
> 
>> +		return ~EINVAL;
>                         ^
>                  This is not a minus :-).

Sorry, it is a typo. I am going to fix it.

> 
>> +	priv->ttl = nla_get_u8(tb[NFTA_OSF_TTL]);
>> +
>>   	priv->dreg = nft_parse_register(tb[NFTA_OSF_DREG]);
>>   	err = nft_validate_register_store(ctx, priv->dreg, NULL,
>>   					  NFTA_DATA_VALUE, NFT_OSF_MAXGENRELEN);
>> @@ -60,6 +69,9 @@ static int nft_osf_dump(struct sk_buff *skb, const struct nft_expr *expr)
>>   {
>>   	const struct nft_osf *priv = nft_expr_priv(expr);
>>   
>> +	if (nla_put_u8(skb, NFTA_OSF_TTL, priv->ttl))
>> +		goto nla_put_failure;
>> +
>>   	if (nft_dump_register(skb, NFTA_OSF_DREG, priv->dreg))
>>   		goto nla_put_failure;
>>   
>> -- 
>> 2.18.0
>>
diff mbox series

Patch

diff --git a/include/linux/netfilter/nfnetlink_osf.h b/include/linux/netfilter/nfnetlink_osf.h
index ecf7dab81e9e..c6000046c966 100644
--- a/include/linux/netfilter/nfnetlink_osf.h
+++ b/include/linux/netfilter/nfnetlink_osf.h
@@ -27,6 +27,7 @@  bool nf_osf_match(const struct sk_buff *skb, u_int8_t family,
 		  const struct list_head *nf_osf_fingers);
 
 const char *nf_osf_find(const struct sk_buff *skb,
-                        const struct list_head *nf_osf_fingers);
+			const struct list_head *nf_osf_fingers,
+			const int ttl_check);
 
 #endif /* _NFOSF_H */
diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h
index e23290ffdc77..85df36521153 100644
--- a/include/uapi/linux/netfilter/nf_tables.h
+++ b/include/uapi/linux/netfilter/nf_tables.h
@@ -1493,9 +1493,16 @@  enum nft_flowtable_hook_attributes {
 };
 #define NFTA_FLOWTABLE_HOOK_MAX	(__NFTA_FLOWTABLE_HOOK_MAX - 1)
 
+/**
+ * enum nft_osf_attributes - nftables osf expression netlink attributes
+ *
+ * @NFTA_OSF_DREG: destination register (NLA_U32: nft_registers)
+ * @NFTA_OSF_TTL: Value of the TTL osf option (NLA_U8)
+ */
 enum nft_osf_attributes {
 	NFTA_OSF_UNSPEC,
 	NFTA_OSF_DREG,
+	NFTA_OSF_TTL,
 	__NFTA_OSF_MAX,
 };
 #define NFTA_OSF_MAX (__NFTA_OSF_MAX - 1)
diff --git a/include/uapi/linux/netfilter/nfnetlink_osf.h b/include/uapi/linux/netfilter/nfnetlink_osf.h
index 272bc3195f2d..7e0c00658bf8 100644
--- a/include/uapi/linux/netfilter/nfnetlink_osf.h
+++ b/include/uapi/linux/netfilter/nfnetlink_osf.h
@@ -26,6 +26,7 @@ 
 
 #define NF_OSF_FLAGMASK		(NF_OSF_GENRE | NF_OSF_TTL | \
 				 NF_OSF_LOG | NF_OSF_INVERT)
+
 /* Wildcard MSS (kind of).
  * It is used to implement a state machine for the different wildcard values
  * of the MSS and window sizes.
diff --git a/net/netfilter/nfnetlink_osf.c b/net/netfilter/nfnetlink_osf.c
index 00db27dfd2ff..ec8fa9661538 100644
--- a/net/netfilter/nfnetlink_osf.c
+++ b/net/netfilter/nfnetlink_osf.c
@@ -257,7 +257,8 @@  nf_osf_match(const struct sk_buff *skb, u_int8_t family,
 EXPORT_SYMBOL_GPL(nf_osf_match);
 
 const char *nf_osf_find(const struct sk_buff *skb,
-			const struct list_head *nf_osf_fingers)
+			const struct list_head *nf_osf_fingers,
+			const int ttl_check)
 {
 	const struct iphdr *ip = ip_hdr(skb);
 	const struct nf_osf_user_finger *f;
@@ -275,7 +276,7 @@  const char *nf_osf_find(const struct sk_buff *skb,
 
 	list_for_each_entry_rcu(kf, &nf_osf_fingers[ctx.df], finger_entry) {
 		f = &kf->finger;
-		if (!nf_osf_match_one(skb, f, -1, &ctx))
+		if (!nf_osf_match_one(skb, f, ttl_check, &ctx))
 			continue;
 
 		genre = f->genre;
diff --git a/net/netfilter/nft_osf.c b/net/netfilter/nft_osf.c
index 5af74b37f423..b63c5f5c716b 100644
--- a/net/netfilter/nft_osf.c
+++ b/net/netfilter/nft_osf.c
@@ -6,10 +6,12 @@ 
 
 struct nft_osf {
 	enum nft_registers	dreg:8;
+	u8			ttl;
 };
 
 static const struct nla_policy nft_osf_policy[NFTA_OSF_MAX + 1] = {
 	[NFTA_OSF_DREG]		= { .type = NLA_U32 },
+	[NFTA_OSF_TTL]		= { .type = NLA_U8 },
 };
 
 static void nft_osf_eval(const struct nft_expr *expr, struct nft_regs *regs,
@@ -21,6 +23,7 @@  static void nft_osf_eval(const struct nft_expr *expr, struct nft_regs *regs,
 	const struct tcphdr *tcp;
 	struct tcphdr _tcph;
 	const char *os_name;
+	int ttl_check;
 
 	tcp = skb_header_pointer(skb, ip_hdrlen(skb),
 				 sizeof(struct tcphdr), &_tcph);
@@ -33,7 +36,8 @@  static void nft_osf_eval(const struct nft_expr *expr, struct nft_regs *regs,
 		return;
 	}
 
-	os_name = nf_osf_find(skb, nf_osf_fingers);
+	ttl_check = priv->ttl;
+	os_name = nf_osf_find(skb, nf_osf_fingers, ttl_check);
 	if (!os_name)
 		strncpy((char *)dest, "unknown", NFT_OSF_MAXGENRELEN);
 	else
@@ -47,6 +51,11 @@  static int nft_osf_init(const struct nft_ctx *ctx,
 	struct nft_osf *priv = nft_expr_priv(expr);
 	int err;
 
+	if (!tb[NFTA_OSF_TTL] || nla_get_u8(tb[NFTA_OSF_TTL]) < 0 ||
+	    nla_get_u8(tb[NFTA_OSF_TTL]) > 2)
+		return ~EINVAL;
+	priv->ttl = nla_get_u8(tb[NFTA_OSF_TTL]);
+
 	priv->dreg = nft_parse_register(tb[NFTA_OSF_DREG]);
 	err = nft_validate_register_store(ctx, priv->dreg, NULL,
 					  NFTA_DATA_VALUE, NFT_OSF_MAXGENRELEN);
@@ -60,6 +69,9 @@  static int nft_osf_dump(struct sk_buff *skb, const struct nft_expr *expr)
 {
 	const struct nft_osf *priv = nft_expr_priv(expr);
 
+	if (nla_put_u8(skb, NFTA_OSF_TTL, priv->ttl))
+		goto nla_put_failure;
+
 	if (nft_dump_register(skb, NFTA_OSF_DREG, priv->dreg))
 		goto nla_put_failure;