[dpdk-dev] [PATCH v1] net/tap: allow user mac to be passed as args

[Vipin Varghese]

One of the uses cases from customer site is use TAP PMD to intake
user specific MAC address during probe. This allows applications
make use of interfaces with desired MAC.

Extending MAC argumentinfrastructure for tap PMD; we pass custom
MAC address in string format (sample - 11:22:33:44:55:66).

Signed-off-by: Vipin Varghese <vipin.vargh...@intel.com>
---
 drivers/net/tap/rte_eth_tap.c | 56 +++++++++++++++++++++++++++++++++++++++----
 1 file changed, 52 insertions(+), 4 deletions(-)

diff --git a/drivers/net/tap/rte_eth_tap.c b/drivers/net/tap/rte_eth_tap.c
index 6b27679..0c53458 100644
--- a/drivers/net/tap/rte_eth_tap.c
+++ b/drivers/net/tap/rte_eth_tap.c
@@ -81,6 +81,8 @@
 #define FLOWER_KERNEL_VERSION KERNEL_VERSION(4, 2, 0)
 #define FLOWER_VLAN_KERNEL_VERSION KERNEL_VERSION(4, 9, 0)
 
+static unsigned char user_mac[ETHER_ADDR_LEN];
+
 static struct rte_vdev_driver pmd_tap_drv;
 
 static const char *valid_arguments[] = {
@@ -1291,13 +1293,20 @@ enum ioctl_mode {
                pmd->txq[i].fd = -1;
        }
 
-       if (fixed_mac_type) {
+       if (fixed_mac_type == 1) {
                /* 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 (fixed_mac_type == 2) {
+               /* user mac is recieved */
+               RTE_LOG(INFO, PMD,
+                       "Using user MAC (%02x:%02x:%02x:%02x:%02x:%02x)\n",
+                       user_mac[0], user_mac[1], user_mac[2],
+                       user_mac[3], user_mac[4], user_mac[5]);
+               rte_memcpy(&pmd->eth_addr, user_mac, ETHER_ADDR_LEN);
        } else {
                eth_random_addr((uint8_t *)&pmd->eth_addr);
        }
@@ -1471,9 +1480,48 @@ enum ioctl_mode {
             const char *value,
             void *extra_args)
 {
-       if (value &&
-           !strncasecmp(ETH_TAP_MAC_FIXED, value, strlen(ETH_TAP_MAC_FIXED)))
-               *(int *)extra_args = 1;
+       char macTemp[20], *macByte = NULL;
+       unsigned int index = 0;
+
+       if (value) {
+               if (!strncasecmp(ETH_TAP_MAC_FIXED, value,
+                       strlen(ETH_TAP_MAC_FIXED))) {
+                       *(int *)extra_args = 1;
+               } else {
+                       RTE_LOG(INFO, PMD, "User shared MAC param (%s)\n",
+                               value);
+
+                       /* desired format aa:bb:cc:dd:ee:ff:11 */
+                       if (strlen(value) == 17) {
+                               strncpy(macTemp, value, 18);
+
+                               macByte = strtok(macTemp, ":");
+                               while ((macByte != NULL) &&
+                                       (strspn(macByte, 
"0123456789ABCDEFabcdef")) &&
+                                       (strspn((macByte + 1), 
"0123456789ABCDEFabcdef")) &&
+                                       (strlen(macByte) == 2)) {
+                                       user_mac[index] = strtoul(macByte, 
NULL, 16);
+                                       macByte = strtok(NULL, ":");
+                                       index += 1;
+                               }
+
+                               if (index != 6) {
+                                       RTE_LOG(ERR, PMD, " failure in MAC 
value (%s) at %u\n",
+                                               macByte, index + 1);
+                                       return -1;
+                               }
+
+                               RTE_LOG(DEBUG, PMD, " User MAC (%s) 
considered\n",
+                                       value);
+                               *(int *)extra_args = 2;
+                       } else {
+                               RTE_LOG(ERR, PMD, " Mismatch on format for 
(%s)\n",
+                                       value);
+                               return -1;
+                       }
+               }
+       }
+
        return 0;
 }
 
-- 
1.9.1