diff mbox series

net/memif: use abstract socket address

Message ID 20201005123900.32723-1-jgrajcia@cisco.com (mailing list archive)
State Superseded, archived
Delegated to: Ferruh Yigit
Headers show
Series net/memif: use abstract socket address | expand

Checks

Context Check Description
ci/iol-testing success Testing PASS
ci/checkpatch warning coding style issues
ci/iol-mellanox-Performance success Performance Testing PASS
ci/travis-robot success Travis build: passed
ci/iol-intel-Performance success Performance Testing PASS
ci/Intel-compilation success Compilation OK
ci/iol-broadcom-Functional success Functional Testing PASS
ci/iol-intel-Functional success Functional Testing PASS
ci/iol-broadcom-Performance success Performance Testing PASS

Commit Message

Abstract socket address has no connection with
filesystem pathnames and the socket dissapears
once all open references are closed.

Memif pmd will use abstract socket address by default.
For backwards compatibility use new argument
'socket-abstract=no'

Signed-off-by: Jakub Grajciar <jgrajcia@cisco.com>
---
 doc/guides/nics/memif.rst         |  1 +
 drivers/net/memif/memif_socket.c  | 25 +++++++++++++++--------
 drivers/net/memif/rte_eth_memif.c | 34 ++++++++++++++++++++++++++++++-
 drivers/net/memif/rte_eth_memif.h | 10 +++++----
 4 files changed, 57 insertions(+), 13 deletions(-)

Comments

Ferruh Yigit Oct. 5, 2020, 1:09 p.m. UTC | #1
On 10/5/2020 1:39 PM, Jakub Grajciar wrote:
> Abstract socket address has no connection with
> filesystem pathnames and the socket dissapears
> once all open references are closed.
> 
> Memif pmd will use abstract socket address by default.
> For backwards compatibility use new argument
> 'socket-abstract=no'
> 

Why this backward compatibility is required? How the end user affected from 
swithching to abstract sockets?
Since when linux supports abstract sockets, does this switch will cause problem 
with old kernel versions?

Is there any benefit of the abstract sockets other than socket cleaned 
automatically (I assume for unix sockets it is done when file filesystem 
reference removed)?

> Signed-off-by: Jakub Grajciar <jgrajcia@cisco.com>
> ---
>   doc/guides/nics/memif.rst         |  1 +
>   drivers/net/memif/memif_socket.c  | 25 +++++++++++++++--------
>   drivers/net/memif/rte_eth_memif.c | 34 ++++++++++++++++++++++++++++++-
>   drivers/net/memif/rte_eth_memif.h | 10 +++++----
>   4 files changed, 57 insertions(+), 13 deletions(-)
> 
> diff --git a/doc/guides/nics/memif.rst b/doc/guides/nics/memif.rst
> index ddeebed25..8e80105a4 100644
> --- a/doc/guides/nics/memif.rst
> +++ b/doc/guides/nics/memif.rst
> @@ -43,6 +43,7 @@ client.
>      "bsize=1024", "Size of single packet buffer", "2048", "uint16_t"
>      "rsize=11", "Log2 of ring size. If rsize is 10, actual ring size is 1024", "10", "1-14"
>      "socket=/tmp/memif.sock", "Socket filename", "/tmp/memif.sock", "string len 108"
> +   "socket-abstract=no", "Set usage of abstract socket address", "yes", "yes|no"
>      "mac=01:23:45:ab:cd:ef", "Mac address", "01:ab:23:cd:45:ef", ""
>      "secret=abc123", "Secret is an optional security option, which if specified, must be matched by peer", "", "string len 24"
>      "zero-copy=yes", "Enable/disable zero-copy slave mode. Only relevant to slave, requires '--single-file-segments' eal argument", "no", "yes|no"
> diff --git a/drivers/net/memif/memif_socket.c b/drivers/net/memif/memif_socket.c
> index 67794cb6f..4b0b12ead 100644
> --- a/drivers/net/memif/memif_socket.c
> +++ b/drivers/net/memif/memif_socket.c
> @@ -862,10 +862,10 @@ memif_listener_handler(void *arg)
>   }
>   
>   static struct memif_socket *
> -memif_socket_create(char *key, uint8_t listener)
> +memif_socket_create(char *key, uint8_t listener, bool is_abstract)
>   {
>   	struct memif_socket *sock;
> -	struct sockaddr_un un;
> +	struct sockaddr_un un = { 0 };
>   	int sockfd;
>   	int ret;
>   	int on = 1;
> @@ -886,7 +886,12 @@ memif_socket_create(char *key, uint8_t listener)
>   			goto error;
>   
>   		un.sun_family = AF_UNIX;
> -		strlcpy(un.sun_path, sock->filename, MEMIF_SOCKET_UN_SIZE);
> +		if (is_abstract) {
> +			// abstract address

Please don't prefer c99 comment sytle, there are a few occurrences below.
> -----Original Message-----
> From: Ferruh Yigit <ferruh.yigit@intel.com>
> Sent: Monday, October 5, 2020 3:09 PM
> To: Jakub Grajciar -X (jgrajcia - PANTHEON TECH SRO at Cisco)
> <jgrajcia@cisco.com>; dev@dpdk.org
> Subject: Re: [dpdk-dev] [PATCH] net/memif: use abstract socket address
> 
> On 10/5/2020 1:39 PM, Jakub Grajciar wrote:
> > Abstract socket address has no connection with filesystem pathnames
> > and the socket dissapears once all open references are closed.
> >
> > Memif pmd will use abstract socket address by default.
> > For backwards compatibility use new argument 'socket-abstract=no'
> >
> 
> Why this backward compatibility is required? How the end user affected from
> swithching to abstract sockets?
> Since when linux supports abstract sockets, does this switch will cause problem
> with old kernel versions?
> 
> Is there any benefit of the abstract sockets other than socket cleaned
> automatically (I assume for unix sockets it is done when file filesystem reference
> removed)?
> 

What I mean by this is compatibility with other implementations and older versions of the driver, e.g. vpp and libmemif don't support abstract socket yet.
Stephen Hemminger Oct. 5, 2020, 6:17 p.m. UTC | #3
On Mon, 5 Oct 2020 14:09:20 +0100
Ferruh Yigit <ferruh.yigit@intel.com> wrote:

> On 10/5/2020 1:39 PM, Jakub Grajciar wrote:
> > Abstract socket address has no connection with
> > filesystem pathnames and the socket dissapears
> > once all open references are closed.
> > 
> > Memif pmd will use abstract socket address by default.
> > For backwards compatibility use new argument
> > 'socket-abstract=no'
> >   
> 
> Why this backward compatibility is required? How the end user affected from 
> swithching to abstract sockets?

It would only matter if mixing applications with different versions.

> Since when linux supports abstract sockets, does this switch will cause problem 
> with old kernel versions?

This is not new, it dates back to Linux 2.4 or earlier.

> 
> Is there any benefit of the abstract sockets other than socket cleaned 
> automatically (I assume for unix sockets it is done when file filesystem 
> reference removed)?

The big one is that applications don't have to blindly unlink the old filesystem
remnant. This means that if application can't bind it means another application
is still running with that name. So abstract sockets are safer.


Abstract sockets are not pathnames so they get handled differently by security
systems (like SELinux and AppArmor). This can be helpful in containers.
Ferruh Yigit Oct. 6, 2020, 8:59 a.m. UTC | #4
On 10/5/2020 7:17 PM, Stephen Hemminger wrote:
> On Mon, 5 Oct 2020 14:09:20 +0100
> Ferruh Yigit <ferruh.yigit@intel.com> wrote:
> 
>> On 10/5/2020 1:39 PM, Jakub Grajciar wrote:
>>> Abstract socket address has no connection with
>>> filesystem pathnames and the socket dissapears
>>> once all open references are closed.
>>>
>>> Memif pmd will use abstract socket address by default.
>>> For backwards compatibility use new argument
>>> 'socket-abstract=no'
>>>    
>>
>> Why this backward compatibility is required? How the end user affected from
>> swithching to abstract sockets?
> 
> It would only matter if mixing applications with different versions.
> 
>> Since when linux supports abstract sockets, does this switch will cause problem
>> with old kernel versions?
> 
> This is not new, it dates back to Linux 2.4 or earlier.
> 
>>
>> Is there any benefit of the abstract sockets other than socket cleaned
>> automatically (I assume for unix sockets it is done when file filesystem
>> reference removed)?
> 
> The big one is that applications don't have to blindly unlink the old filesystem
> remnant. This means that if application can't bind it means another application
> is still running with that name. So abstract sockets are safer.
> 
> 
> Abstract sockets are not pathnames so they get handled differently by security
> systems (like SELinux and AppArmor). This can be helpful in containers.
> 

Hi Stephen, thank you for clarification.
Stephen Hemminger Oct. 7, 2020, 3:03 p.m. UTC | #5
On Mon, 5 Oct 2020 14:39:00 +0200
Jakub Grajciar <jgrajcia@cisco.com> wrote:

> @@ -886,7 +886,12 @@ memif_socket_create(char *key, uint8_t listener)
>  			goto error;
>  
>  		un.sun_family = AF_UNIX;
> -		strlcpy(un.sun_path, sock->filename, MEMIF_SOCKET_UN_SIZE);
> +		if (is_abstract) {
> +			// abstract address
No C++ comments please.

> +			un.sun_path[0] = '\0';
Already set to zero when initialized.

> +	if (pmd->flags & ETH_MEMIF_FLAG_SOCKET_ABSTRACT) {
> +		// abstract address
ditto no C++ comments

> +		sun.sun_path[0] = '\0';
again zeroed again

> +		memcpy(sun.sun_path + 1, pmd->socket_filename, sizeof(sun.sun_path) - 2);
> +	} else
> +		memcpy(sun.sun_path, pmd->socket_filename, sizeof(sun.sun_path) - 1);

This code is buggy since it potentially reads past the end of the strinc in filename.
Use strlcpy here instead.
Ferruh Yigit Oct. 9, 2020, 3:09 p.m. UTC | #6
On 10/7/2020 4:03 PM, Stephen Hemminger wrote:
> On Mon, 5 Oct 2020 14:39:00 +0200
> Jakub Grajciar <jgrajcia@cisco.com> wrote:
> 
>> @@ -886,7 +886,12 @@ memif_socket_create(char *key, uint8_t listener)
>>   			goto error;
>>   
>>   		un.sun_family = AF_UNIX;
>> -		strlcpy(un.sun_path, sock->filename, MEMIF_SOCKET_UN_SIZE);
>> +		if (is_abstract) {
>> +			// abstract address
> No C++ comments please.
> 
>> +			un.sun_path[0] = '\0';
> Already set to zero when initialized.
> 
>> +	if (pmd->flags & ETH_MEMIF_FLAG_SOCKET_ABSTRACT) {
>> +		// abstract address
> ditto no C++ comments
> 
>> +		sun.sun_path[0] = '\0';
> again zeroed again
> 
>> +		memcpy(sun.sun_path + 1, pmd->socket_filename, sizeof(sun.sun_path) - 2);
>> +	} else
>> +		memcpy(sun.sun_path, pmd->socket_filename, sizeof(sun.sun_path) - 1);
> 
> This code is buggy since it potentially reads past the end of the strinc in filename.
> Use strlcpy here instead.
> 

Hi Jakub,

v2 is still using memcpy, have you seen Stephen's comment above?
diff mbox series

Patch

diff --git a/doc/guides/nics/memif.rst b/doc/guides/nics/memif.rst
index ddeebed25..8e80105a4 100644
--- a/doc/guides/nics/memif.rst
+++ b/doc/guides/nics/memif.rst
@@ -43,6 +43,7 @@  client.
    "bsize=1024", "Size of single packet buffer", "2048", "uint16_t"
    "rsize=11", "Log2 of ring size. If rsize is 10, actual ring size is 1024", "10", "1-14"
    "socket=/tmp/memif.sock", "Socket filename", "/tmp/memif.sock", "string len 108"
+   "socket-abstract=no", "Set usage of abstract socket address", "yes", "yes|no"
    "mac=01:23:45:ab:cd:ef", "Mac address", "01:ab:23:cd:45:ef", ""
    "secret=abc123", "Secret is an optional security option, which if specified, must be matched by peer", "", "string len 24"
    "zero-copy=yes", "Enable/disable zero-copy slave mode. Only relevant to slave, requires '--single-file-segments' eal argument", "no", "yes|no"
diff --git a/drivers/net/memif/memif_socket.c b/drivers/net/memif/memif_socket.c
index 67794cb6f..4b0b12ead 100644
--- a/drivers/net/memif/memif_socket.c
+++ b/drivers/net/memif/memif_socket.c
@@ -862,10 +862,10 @@  memif_listener_handler(void *arg)
 }
 
 static struct memif_socket *
-memif_socket_create(char *key, uint8_t listener)
+memif_socket_create(char *key, uint8_t listener, bool is_abstract)
 {
 	struct memif_socket *sock;
-	struct sockaddr_un un;
+	struct sockaddr_un un = { 0 };
 	int sockfd;
 	int ret;
 	int on = 1;
@@ -886,7 +886,12 @@  memif_socket_create(char *key, uint8_t listener)
 			goto error;
 
 		un.sun_family = AF_UNIX;
-		strlcpy(un.sun_path, sock->filename, MEMIF_SOCKET_UN_SIZE);
+		if (is_abstract) {
+			// abstract address
+			un.sun_path[0] = '\0';
+			strlcpy(un.sun_path + 1, sock->filename, MEMIF_SOCKET_UN_SIZE - 1);
+		} else
+			strlcpy(un.sun_path, sock->filename, MEMIF_SOCKET_UN_SIZE);
 
 		ret = setsockopt(sockfd, SOL_SOCKET, SO_PASSCRED, &on,
 				 sizeof(on));
@@ -963,7 +968,7 @@  memif_socket_init(struct rte_eth_dev *dev, const char *socket_filename)
 	ret = rte_hash_lookup_data(hash, key, (void **)&socket);
 	if (ret < 0) {
 		socket = memif_socket_create(key,
-					     (pmd->role == MEMIF_ROLE_SLAVE) ? 0 : 1);
+					     (pmd->role == MEMIF_ROLE_SLAVE) ? 0 : 1, pmd->flags & ETH_MEMIF_FLAG_SOCKET_ABSTRACT);
 		if (socket == NULL)
 			return -1;
 		ret = rte_hash_add_key_data(hash, key, socket);
@@ -1025,7 +1030,7 @@  memif_socket_remove_device(struct rte_eth_dev *dev)
 	/* remove socket, if this was the last device using it */
 	if (TAILQ_EMPTY(&socket->dev_queue)) {
 		rte_hash_del_key(hash, socket->filename);
-		if (socket->listener) {
+		if (socket->listener && !(pmd->flags & ETH_MEMIF_FLAG_SOCKET_ABSTRACT)) {
 			/* remove listener socket file,
 			 * so we can create new one later.
 			 */
@@ -1054,7 +1059,7 @@  memif_connect_slave(struct rte_eth_dev *dev)
 {
 	int sockfd;
 	int ret;
-	struct sockaddr_un sun;
+	struct sockaddr_un sun = { 0 };
 	struct pmd_internals *pmd = dev->data->dev_private;
 
 	memset(pmd->local_disc_string, 0, ETH_MEMIF_DISC_STRING_SIZE);
@@ -1068,8 +1073,12 @@  memif_connect_slave(struct rte_eth_dev *dev)
 	}
 
 	sun.sun_family = AF_UNIX;
-
-	memcpy(sun.sun_path, pmd->socket_filename, sizeof(sun.sun_path) - 1);
+	if (pmd->flags & ETH_MEMIF_FLAG_SOCKET_ABSTRACT) {
+		// abstract address
+		sun.sun_path[0] = '\0';
+		memcpy(sun.sun_path + 1, pmd->socket_filename, sizeof(sun.sun_path) - 2);
+	} else
+		memcpy(sun.sun_path, pmd->socket_filename, sizeof(sun.sun_path) - 1);
 
 	ret = connect(sockfd, (struct sockaddr *)&sun,
 		      sizeof(struct sockaddr_un));
diff --git a/drivers/net/memif/rte_eth_memif.c b/drivers/net/memif/rte_eth_memif.c
index c1c7e9f8d..ba285be54 100644
--- a/drivers/net/memif/rte_eth_memif.c
+++ b/drivers/net/memif/rte_eth_memif.c
@@ -36,6 +36,7 @@ 
 #define ETH_MEMIF_PKT_BUFFER_SIZE_ARG	"bsize"
 #define ETH_MEMIF_RING_SIZE_ARG		"rsize"
 #define ETH_MEMIF_SOCKET_ARG		"socket"
+#define ETH_MEMIF_SOCKET_ABSTRACT_ARG	"socket-abstract"
 #define ETH_MEMIF_MAC_ARG		"mac"
 #define ETH_MEMIF_ZC_ARG		"zero-copy"
 #define ETH_MEMIF_SECRET_ARG		"secret"
@@ -46,6 +47,7 @@  static const char * const valid_arguments[] = {
 	ETH_MEMIF_PKT_BUFFER_SIZE_ARG,
 	ETH_MEMIF_RING_SIZE_ARG,
 	ETH_MEMIF_SOCKET_ARG,
+	ETH_MEMIF_SOCKET_ABSTRACT_ARG,
 	ETH_MEMIF_MAC_ARG,
 	ETH_MEMIF_ZC_ARG,
 	ETH_MEMIF_SECRET_ARG,
@@ -1640,7 +1642,23 @@  memif_set_socket_filename(const char *key __rte_unused, const char *value,
 	const char **socket_filename = (const char **)extra_args;
 
 	*socket_filename = value;
-	return memif_check_socket_filename(*socket_filename);
+	return 0;
+}
+
+static int
+memif_set_is_socket_abstract(const char *key __rte_unused, const char *value, void *extra_args)
+{
+	uint32_t *flags = (uint32_t *)extra_args;
+
+	if (strstr(value, "yes") != NULL) {
+		*flags |= ETH_MEMIF_FLAG_SOCKET_ABSTRACT;
+	} else if (strstr(value, "no") != NULL) {
+		*flags &= ~ETH_MEMIF_FLAG_SOCKET_ABSTRACT;
+	} else {
+		MIF_LOG(ERR, "Failed to parse socket-abstract param: %s.", value);
+		return -EINVAL;
+	}
+	return 0;
 }
 
 static int
@@ -1726,6 +1744,9 @@  rte_pmd_memif_probe(struct rte_vdev_device *vdev)
 		MIF_LOG(WARNING, "Failed to register mp action callback: %s",
 			strerror(rte_errno));
 
+	// use abstract address by default
+	flags |= ETH_MEMIF_FLAG_SOCKET_ABSTRACT;
+
 	kvlist = rte_kvargs_parse(rte_vdev_device_args(vdev), valid_arguments);
 
 	/* parse parameters */
@@ -1751,6 +1772,10 @@  rte_pmd_memif_probe(struct rte_vdev_device *vdev)
 					 (void *)(&socket_filename));
 		if (ret < 0)
 			goto exit;
+		ret = rte_kvargs_process(kvlist, ETH_MEMIF_SOCKET_ABSTRACT_ARG,
+					 &memif_set_is_socket_abstract, &flags);
+		if (ret < 0)
+			goto exit;
 		ret = rte_kvargs_process(kvlist, ETH_MEMIF_MAC_ARG,
 					 &memif_set_mac, ether_addr);
 		if (ret < 0)
@@ -1765,6 +1790,12 @@  rte_pmd_memif_probe(struct rte_vdev_device *vdev)
 			goto exit;
 	}
 
+	if (!(flags & ETH_MEMIF_FLAG_SOCKET_ABSTRACT)) {
+		ret = memif_check_socket_filename(socket_filename);
+		if (ret < 0)	
+			goto exit;
+	}
+
 	/* create interface */
 	ret = memif_create(vdev, role, id, flags, socket_filename,
 			   log2_ring_size, pkt_buffer_size, secret, ether_addr);
@@ -1802,6 +1833,7 @@  RTE_PMD_REGISTER_PARAM_STRING(net_memif,
 			      ETH_MEMIF_PKT_BUFFER_SIZE_ARG "=<int>"
 			      ETH_MEMIF_RING_SIZE_ARG "=<int>"
 			      ETH_MEMIF_SOCKET_ARG "=<string>"
+				  ETH_MEMIF_SOCKET_ABSTRACT_ARG "=yes|no"
 			      ETH_MEMIF_MAC_ARG "=xx:xx:xx:xx:xx:xx"
 			      ETH_MEMIF_ZC_ARG "=yes|no"
 			      ETH_MEMIF_SECRET_ARG "=<string>");
diff --git a/drivers/net/memif/rte_eth_memif.h b/drivers/net/memif/rte_eth_memif.h
index 6f45b7072..ac0a2f2d1 100644
--- a/drivers/net/memif/rte_eth_memif.h
+++ b/drivers/net/memif/rte_eth_memif.h
@@ -81,14 +81,16 @@  struct pmd_internals {
 	memif_interface_id_t id;		/**< unique id */
 	enum memif_role_t role;			/**< device role */
 	uint32_t flags;				/**< device status flags */
-#define ETH_MEMIF_FLAG_CONNECTING	(1 << 0)
+#define ETH_MEMIF_FLAG_CONNECTING		(1 << 0)
 /**< device is connecting */
-#define ETH_MEMIF_FLAG_CONNECTED	(1 << 1)
+#define ETH_MEMIF_FLAG_CONNECTED		(1 << 1)
 /**< device is connected */
-#define ETH_MEMIF_FLAG_ZERO_COPY	(1 << 2)
+#define ETH_MEMIF_FLAG_ZERO_COPY		(1 << 2)
 /**< device is zero-copy enabled */
-#define ETH_MEMIF_FLAG_DISABLED		(1 << 3)
+#define ETH_MEMIF_FLAG_DISABLED			(1 << 3)
 /**< device has not been configured and can not accept connection requests */
+#define ETH_MEMIF_FLAG_SOCKET_ABSTRACT	(1 << 4)
+/**< use abstract socket address */
 
 	char *socket_filename;			/**< pointer to socket filename */
 	char secret[ETH_MEMIF_SECRET_SIZE]; /**< secret (optional security parameter) */