net/tap: allow user MAC to be passed as args

Allow TAP PMD to pass user desired MAC address as argument.
The argument value is processed as string delimited by  ':',
is parsed and converted to HEX MAC address after validation.

Signed-off-by: Vipin Varghese <vipin.varghese@intel.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>
Acked-by: Pascal Mazon <pascal.mazon@6wind.com>

diff --git a/doc/guides/nics/tap.rst b/doc/guides/nics/tap.rst
index ea61be3..76eb0bd 100644 (file)
--- a/doc/guides/nics/tap.rst
+++ b/doc/guides/nics/tap.rst
@@ -37,6 +37,12 @@ for each interface string containing ``mac=fixed``. The MAC address is formatted
 as 00:'d':'t':'a':'p':[00-FF]. Convert the characters to hex and you get the
 actual MAC address: ``00:64:74:61:70:[00-FF]``.
 
+   --vdev=net_tap0,mac="00:64:74:61:70:11"
+
+The MAC address will have a user value passed as string. The MAC address is in
+format with delimeter ``:``. The string is byte converted to hex and you get
+the actual MAC address: ``00:64:74:61:70:11``.
+
 It is possible to specify a remote netdevice to capture packets from by adding
 ``remote=foo1``, for example::
 

diff --git a/drivers/net/tap/rte_eth_tap.c b/drivers/net/tap/rte_eth_tap.c
index f09db0e..3e4f7a8 100644 (file)
--- a/drivers/net/tap/rte_eth_tap.c
+++ b/drivers/net/tap/rte_eth_tap.c
@@ -48,6 +48,10 @@
 #define ETH_TAP_MAC_ARG         "mac"
 #define ETH_TAP_MAC_FIXED       "fixed"
 
+#define ETH_TAP_USR_MAC_FMT     "xx:xx:xx:xx:xx:xx"
+#define ETH_TAP_CMP_MAC_FMT     "0123456789ABCDEFabcdef"
+#define ETH_TAP_MAC_ARG_FMT     ETH_TAP_MAC_FIXED "|" ETH_TAP_USR_MAC_FMT
+
 static struct rte_vdev_driver pmd_tap_drv;
 
 static const char *valid_arguments[] = {
@@ -1337,7 +1341,7 @@ static const struct eth_dev_ops ops = {
 
 static int
 eth_dev_tap_create(struct rte_vdev_device *vdev, char *tap_name,
-                  char *remote_iface, int fixed_mac_type)
+                  char *remote_iface, struct ether_addr *mac_addr)
 {
        int numa_node = rte_socket_id();
        struct rte_eth_dev *dev;
@@ -1399,16 +1403,10 @@ eth_dev_tap_create(struct rte_vdev_device *vdev, char *tap_name,
                pmd->txq[i].fd = -1;
        }
 
-       if (fixed_mac_type) {
-               /* fixed mac = 00:64:74:61:70:<iface_idx> */
-               static int iface_idx;
-               char mac[ETHER_ADDR_LEN] = "\0dtap";
-
-               mac[ETHER_ADDR_LEN - 1] = iface_idx++;
-               rte_memcpy(&pmd->eth_addr, mac, ETHER_ADDR_LEN);
-       } else {
+       if (is_zero_ether_addr(mac_addr))
                eth_random_addr((uint8_t *)&pmd->eth_addr);
-       }
+       else
+               rte_memcpy(&pmd->eth_addr, mac_addr, sizeof(mac_addr));
 
        /* Immediately create the netdevice (this will create the 1st queue). */
        /* rx queue */
@@ -1569,15 +1567,58 @@ set_remote_iface(const char *key __rte_unused,
        return 0;
 }
 
+static int parse_user_mac(struct ether_addr *user_mac,
+               const char *value)
+{
+       unsigned int index = 0;
+       char mac_temp[strlen(ETH_TAP_USR_MAC_FMT) + 1], *mac_byte = NULL;
+
+       if (user_mac == NULL || value == NULL)
+               return 0;
+
+       snprintf(mac_temp, sizeof(mac_temp), "%s", value);
+       mac_byte = strtok(mac_temp, ":");
+
+       while ((mac_byte != NULL) &&
+                       (strlen(mac_byte) <= 2) &&
+                       (strlen(mac_byte) == strspn(mac_byte,
+                                       ETH_TAP_CMP_MAC_FMT))) {
+               user_mac->addr_bytes[index++] = strtoul(mac_byte, NULL, 16);
+               mac_byte = strtok(NULL, ":");
+       }
+
+       return index;
+}
+
 static int
 set_mac_type(const char *key __rte_unused,
             const char *value,
             void *extra_args)
 {
-       if (value &&
-           !strncasecmp(ETH_TAP_MAC_FIXED, value, strlen(ETH_TAP_MAC_FIXED)))
-               *(int *)extra_args = 1;
+       struct ether_addr *user_mac = extra_args;
+
+       if (!value)
+               return 0;
+
+       if (!strncasecmp(ETH_TAP_MAC_FIXED, value, strlen(ETH_TAP_MAC_FIXED))) {
+               static int iface_idx;
+
+               /* fixed mac = 00:64:74:61:70:<iface_idx> */
+               memcpy((char *)user_mac->addr_bytes, "\0dtap", ETHER_ADDR_LEN);
+               user_mac->addr_bytes[ETHER_ADDR_LEN - 1] = iface_idx++ + '0';
+               goto success;
+       }
+
+       if (parse_user_mac(user_mac, value) != 6)
+               goto error;
+success:
+       RTE_LOG(DEBUG, PMD, "TAP user MAC param (%s)\n", value);
        return 0;
+
+error:
+       RTE_LOG(ERR, PMD, "TAP user MAC (%s) is not in format (%s|%s)\n",
+               value, ETH_TAP_MAC_FIXED, ETH_TAP_USR_MAC_FMT);
+       return -1;
 }
 
 /* Open a TAP interface device.
@@ -1591,7 +1632,7 @@ rte_pmd_tap_probe(struct rte_vdev_device *dev)
        int speed;
        char tap_name[RTE_ETH_NAME_MAX_LEN];
        char remote_iface[RTE_ETH_NAME_MAX_LEN];
-       int fixed_mac_type = 0;
+       struct ether_addr user_mac = { .addr_bytes = {0} };
 
        name = rte_vdev_device_name(dev);
        params = rte_vdev_device_args(dev);
@@ -1628,7 +1669,7 @@ rte_pmd_tap_probe(struct rte_vdev_device *dev)
                                ret = rte_kvargs_process(kvlist,
                                                         ETH_TAP_MAC_ARG,
                                                         &set_mac_type,
-                                                        &fixed_mac_type);
+                                                        &user_mac);
                                if (ret == -1)
                                        goto leave;
                        }
@@ -1639,7 +1680,7 @@ rte_pmd_tap_probe(struct rte_vdev_device *dev)
        RTE_LOG(NOTICE, PMD, "Initializing pmd_tap for %s as %s\n",
                name, tap_name);
 
-       ret = eth_dev_tap_create(dev, tap_name, remote_iface, fixed_mac_type);
+       ret = eth_dev_tap_create(dev, tap_name, remote_iface, &user_mac);
 
 leave:
        if (ret == -1) {
@@ -1703,5 +1744,5 @@ RTE_PMD_REGISTER_VDEV(net_tap, pmd_tap_drv);
 RTE_PMD_REGISTER_ALIAS(net_tap, eth_tap);
 RTE_PMD_REGISTER_PARAM_STRING(net_tap,
                              ETH_TAP_IFACE_ARG "=<string> "
-                             ETH_TAP_MAC_ARG "=" ETH_TAP_MAC_FIXED " "
+                             ETH_TAP_MAC_ARG "=" ETH_TAP_MAC_ARG_FMT " "
                              ETH_TAP_REMOTE_ARG "=<string>");