netiucv: allow multiple interfaces to same peer

The NETIUCV device driver allows to connect a Linux guest on z/VM to
another z/VM guest based on the z/VM communication facility IUCV.
Multiple output paths to different guests are possible, as well as
multiple input paths from different guests.
With this feature, you can configure multiple point-to-point NETIUCV
interfaces between your Linux on System z instance and another z/VM
guest.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 135 insertions, 82 deletions

diff --git a/drivers/s390/net/netiucv.c b/drivers/s390/net/netiucv.c
index b6a6356d09b3..8160591913f9 100644
--- a/drivers/s390/net/netiucv.c
+++ b/drivers/s390/net/netiucv.c
@@ -63,6 +63,7 @@
 
 #include <asm/io.h>
 #include <asm/uaccess.h>
+#include <asm/ebcdic.h>
 
 #include <net/iucv/iucv.h>
 #include "fsm.h"
@@ -75,7 +76,7 @@ MODULE_DESCRIPTION ("Linux for S/390 IUCV network driver");
  * Debug Facility stuff
  */
 #define IUCV_DBF_SETUP_NAME "iucv_setup"
-#define IUCV_DBF_SETUP_LEN 32
+#define IUCV_DBF_SETUP_LEN 64
 #define IUCV_DBF_SETUP_PAGES 2
 #define IUCV_DBF_SETUP_NR_AREAS 1
 #define IUCV_DBF_SETUP_LEVEL 3
@@ -226,6 +227,7 @@ struct iucv_connection {
         struct net_device         *netdev;
         struct connection_profile prof;
         char                      userid[9];
+        char                      userdata[17];
 };
 
 /**
@@ -263,7 +265,7 @@ struct ll_header {
 };
 
 #define NETIUCV_HDRLEN           (sizeof(struct ll_header))
-#define NETIUCV_BUFSIZE_MAX      32768
+#define NETIUCV_BUFSIZE_MAX      65537
 #define NETIUCV_BUFSIZE_DEFAULT  NETIUCV_BUFSIZE_MAX
 #define NETIUCV_MTU_MAX          (NETIUCV_BUFSIZE_MAX - NETIUCV_HDRLEN)
 #define NETIUCV_MTU_DEFAULT      9216
@@ -288,7 +290,12 @@ static inline int netiucv_test_and_set_busy(struct net_device *dev)
         return test_and_set_bit(0, &priv->tbusy);
 }
 
-static u8 iucvMagic[16] = {
+static u8 iucvMagic_ascii[16] = {
+        0x30, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+        0x30, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20
+};
+
+static u8 iucvMagic_ebcdic[16] = {
         0xF0, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40,
         0xF0, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40
 };
@@ -301,18 +308,38 @@ static u8 iucvMagic[16] = {
  *
  * @returns The printable string (static data!!)
  */
-static char *netiucv_printname(char *name)
+static char *netiucv_printname(char *name, int len)
 {
-        static char tmp[9];
+        static char tmp[17];
         char *p = tmp;
-        memcpy(tmp, name, 8);
-        tmp[8] = '\0';
-        while (*p && (!isspace(*p)))
+        memcpy(tmp, name, len);
+        tmp[len] = '\0';
+        while (*p && ((p - tmp) < len) && (!isspace(*p)))
                 p++;
         *p = '\0';
         return tmp;
 }
 
+static char *netiucv_printuser(struct iucv_connection *conn)
+{
+        static char tmp_uid[9];
+        static char tmp_udat[17];
+        static char buf[100];
+
+        if (memcmp(conn->userdata, iucvMagic_ebcdic, 16)) {
+                tmp_uid[8] = '\0';
+                tmp_udat[16] = '\0';
+                memcpy(tmp_uid, conn->userid, 8);
+                memcpy(tmp_uid, netiucv_printname(tmp_uid, 8), 8);
+                memcpy(tmp_udat, conn->userdata, 16);
+                EBCASC(tmp_udat, 16);
+                memcpy(tmp_udat, netiucv_printname(tmp_udat, 16), 16);
+                sprintf(buf, "%s.%s", tmp_uid, tmp_udat);
+                return buf;
+        } else
+                return netiucv_printname(conn->userid, 8);
+}
+
 /**
  * States of the interface statemachine.
  */
@@ -563,15 +590,18 @@ static int netiucv_callback_connreq(struct iucv_path *path,
 {
         struct iucv_connection *conn = path->private;
         struct iucv_event ev;
+        static char tmp_user[9];
+        static char tmp_udat[17];
         int rc;
 
-        if (memcmp(iucvMagic, ipuser, 16))
-                /* ipuser must match iucvMagic. */
-                return -EINVAL;
         rc = -EINVAL;
+        memcpy(tmp_user, netiucv_printname(ipvmid, 8), 8);
+        memcpy(tmp_udat, ipuser, 16);
+        EBCASC(tmp_udat, 16);
         read_lock_bh(&iucv_connection_rwlock);
         list_for_each_entry(conn, &iucv_connection_list, list) {
-                if (strncmp(ipvmid, conn->userid, 8))
+                if (strncmp(ipvmid, conn->userid, 8) ||
+                    strncmp(ipuser, conn->userdata, 16))
                         continue;
                 /* Found a matching connection for this path. */
                 conn->path = path;
@@ -580,6 +610,8 @@ static int netiucv_callback_connreq(struct iucv_path *path,
                 fsm_event(conn->fsm, CONN_EVENT_CONN_REQ, &ev);
                 rc = 0;
         }
+        IUCV_DBF_TEXT_(setup, 2, "Connection requested for %s.%s\n",
+                       tmp_user, netiucv_printname(tmp_udat, 16));
         read_unlock_bh(&iucv_connection_rwlock);
         return rc;
 }
@@ -816,7 +848,7 @@ static void conn_action_connaccept(fsm_instance *fi, int event, void *arg)
         conn->path = path;
         path->msglim = NETIUCV_QUEUELEN_DEFAULT;
         path->flags = 0;
-        rc = iucv_path_accept(path, &netiucv_handler, NULL, conn);
+        rc = iucv_path_accept(path, &netiucv_handler, conn->userdata , conn);
         if (rc) {
                 IUCV_DBF_TEXT_(setup, 2, "rc %d from iucv_accept", rc);
                 return;
@@ -854,7 +886,7 @@ static void conn_action_conntimsev(fsm_instance *fi, int event, void *arg)
 
         IUCV_DBF_TEXT(trace, 3, __func__);
         fsm_deltimer(&conn->timer);
-        iucv_path_sever(conn->path, NULL);
+        iucv_path_sever(conn->path, conn->userdata);
         fsm_newstate(fi, CONN_STATE_STARTWAIT);
 }
 
@@ -867,9 +899,9 @@ static void conn_action_connsever(fsm_instance *fi, int event, void *arg)
         IUCV_DBF_TEXT(trace, 3, __func__);
 
         fsm_deltimer(&conn->timer);
-        iucv_path_sever(conn->path, NULL);
-        dev_info(privptr->dev, "The peer interface of the IUCV device"
-                " has closed the connection\n");
+        iucv_path_sever(conn->path, conn->userdata);
+        dev_info(privptr->dev, "The peer z/VM guest %s has closed the "
+                               "connection\n", netiucv_printuser(conn));
         IUCV_DBF_TEXT(data, 2,
                       "conn_action_connsever: Remote dropped connection\n");
         fsm_newstate(fi, CONN_STATE_STARTWAIT);
@@ -886,8 +918,6 @@ static void conn_action_start(fsm_instance *fi, int event, void *arg)
         IUCV_DBF_TEXT(trace, 3, __func__);
 
         fsm_newstate(fi, CONN_STATE_STARTWAIT);
-        IUCV_DBF_TEXT_(setup, 2, "%s('%s'): connecting ...\n",
-                netdev->name, conn->userid);
 
         /*
          * We must set the state before calling iucv_connect because the
@@ -897,8 +927,11 @@ static void conn_action_start(fsm_instance *fi, int event, void *arg)
 
         fsm_newstate(fi, CONN_STATE_SETUPWAIT);
         conn->path = iucv_path_alloc(NETIUCV_QUEUELEN_DEFAULT, 0, GFP_KERNEL);
+        IUCV_DBF_TEXT_(setup, 2, "%s: connecting to %s ...\n",
+                netdev->name, netiucv_printuser(conn));
+
         rc = iucv_path_connect(conn->path, &netiucv_handler, conn->userid,
-                               NULL, iucvMagic, conn);
+                               NULL, conn->userdata, conn);
         switch (rc) {
         case 0:
                 netdev->tx_queue_len = conn->path->msglim;
@@ -908,13 +941,13 @@ static void conn_action_start(fsm_instance *fi, int event, void *arg)
         case 11:
                 dev_warn(privptr->dev,
                         "The IUCV device failed to connect to z/VM guest %s\n",
-                        netiucv_printname(conn->userid));
+                        netiucv_printname(conn->userid, 8));
                 fsm_newstate(fi, CONN_STATE_STARTWAIT);
                 break;
         case 12:
                 dev_warn(privptr->dev,
                         "The IUCV device failed to connect to the peer on z/VM"
-                        " guest %s\n", netiucv_printname(conn->userid));
+                        " guest %s\n", netiucv_printname(conn->userid, 8));
                 fsm_newstate(fi, CONN_STATE_STARTWAIT);
                 break;
         case 13:
@@ -927,7 +960,7 @@ static void conn_action_start(fsm_instance *fi, int event, void *arg)
                 dev_err(privptr->dev,
                         "z/VM guest %s has too many IUCV connections"
                         " to connect with the IUCV device\n",
-                        netiucv_printname(conn->userid));
+                        netiucv_printname(conn->userid, 8));
                 fsm_newstate(fi, CONN_STATE_CONNERR);
                 break;
         case 15:
@@ -972,7 +1005,7 @@ static void conn_action_stop(fsm_instance *fi, int event, void *arg)
         netiucv_purge_skb_queue(&conn->collect_queue);
         if (conn->path) {
                 IUCV_DBF_TEXT(trace, 5, "calling iucv_path_sever\n");
-                iucv_path_sever(conn->path, iucvMagic);
+                iucv_path_sever(conn->path, conn->userdata);
                 kfree(conn->path);
                 conn->path = NULL;
         }
@@ -1090,7 +1123,8 @@ dev_action_connup(fsm_instance *fi, int event, void *arg)
                         fsm_newstate(fi, DEV_STATE_RUNNING);
                         dev_info(privptr->dev,
                                 "The IUCV device has been connected"
-                                " successfully to %s\n", privptr->conn->userid);
+                                " successfully to %s\n",
+                                netiucv_printuser(privptr->conn));
                         IUCV_DBF_TEXT(setup, 3,
                                 "connection is up and running\n");
                         break;
@@ -1452,45 +1486,72 @@ static ssize_t user_show(struct device *dev, struct device_attribute *attr,
         struct netiucv_priv *priv = dev_get_drvdata(dev);
 
         IUCV_DBF_TEXT(trace, 5, __func__);
-        return sprintf(buf, "%s\n", netiucv_printname(priv->conn->userid));
+        return sprintf(buf, "%s\n", netiucv_printuser(priv->conn));
 }
 
-static ssize_t user_write(struct device *dev, struct device_attribute *attr,
-                          const char *buf, size_t count)
+static int netiucv_check_user(const char *buf, size_t count, char *username,
+                              char *userdata)
 {
-        struct netiucv_priv *priv = dev_get_drvdata(dev);
-        struct net_device *ndev = priv->conn->netdev;
-        char    *p;
-        char    *tmp;
-        char    username[9];
-        int     i;
-        struct iucv_connection *cp;
+        const char *p;
+        int i;
 
-        IUCV_DBF_TEXT(trace, 3, __func__);
-        if (count > 9) {
-                IUCV_DBF_TEXT_(setup, 2,
-                               "%d is length of username\n", (int) count);
+        p = strchr(buf, '.');
+        if ((p && ((count > 26) ||
+                   ((p - buf) > 8) ||
+                   (buf + count - p > 18))) ||
+            (!p && (count > 9))) {
+                IUCV_DBF_TEXT(setup, 2, "conn_write: too long\n");
                 return -EINVAL;
         }
 
-        tmp = strsep((char **) &buf, "\n");
-        for (i = 0, p = tmp; i < 8 && *p; i++, p++) {
-                if (isalnum(*p) || (*p == '$')) {
-                        username[i]= toupper(*p);
+        for (i = 0, p = buf; i < 8 && *p && *p != '.'; i++, p++) {
+                if (isalnum(*p) || *p == '$') {
+                        username[i] = toupper(*p);
                         continue;
                 }
-                if (*p == '\n') {
+                if (*p == '\n')
                         /* trailing lf, grr */
                         break;
-                }
                 IUCV_DBF_TEXT_(setup, 2,
-                               "username: invalid character %c\n", *p);
+                               "conn_write: invalid character %02x\n", *p);
                 return -EINVAL;
         }
         while (i < 8)
                 username[i++] = ' ';
         username[8] = '\0';
 
+        if (*p == '.') {
+                p++;
+                for (i = 0; i < 16 && *p; i++, p++) {
+                        if (*p == '\n')
+                                break;
+                        userdata[i] = toupper(*p);
+                }
+                while (i > 0 && i < 16)
+                        userdata[i++] = ' ';
+        } else
+                memcpy(userdata, iucvMagic_ascii, 16);
+        userdata[16] = '\0';
+        ASCEBC(userdata, 16);
+
+        return 0;
+}
+
+static ssize_t user_write(struct device *dev, struct device_attribute *attr,
+                          const char *buf, size_t count)
+{
+        struct netiucv_priv *priv = dev_get_drvdata(dev);
+        struct net_device *ndev = priv->conn->netdev;
+        char    username[9];
+        char    userdata[17];
+        int     rc;
+        struct iucv_connection *cp;
+
+        IUCV_DBF_TEXT(trace, 3, __func__);
+        rc = netiucv_check_user(buf, count, username, userdata);
+        if (rc)
+                return rc;
+
         if (memcmp(username, priv->conn->userid, 9) &&
             (ndev->flags & (IFF_UP | IFF_RUNNING))) {
                 /* username changed while the interface is active. */
@@ -1499,15 +1560,17 @@ static ssize_t user_write(struct device *dev, struct device_attribute *attr,
         }
         read_lock_bh(&iucv_connection_rwlock);
         list_for_each_entry(cp, &iucv_connection_list, list) {
-                if (!strncmp(username, cp->userid, 9) && cp->netdev != ndev) {
+                if (!strncmp(username, cp->userid, 9) &&
+                   !strncmp(userdata, cp->userdata, 17) && cp->netdev != ndev) {
                         read_unlock_bh(&iucv_connection_rwlock);
-                        IUCV_DBF_TEXT_(setup, 2, "user_write: Connection "
-                                "to %s already exists\n", username);
+                        IUCV_DBF_TEXT_(setup, 2, "user_write: Connection to %s "
+                                "already exists\n", netiucv_printuser(cp));
                         return -EEXIST;
                 }
         }
         read_unlock_bh(&iucv_connection_rwlock);
         memcpy(priv->conn->userid, username, 9);
+        memcpy(priv->conn->userdata, userdata, 17);
         return count;
 }
 
@@ -1537,7 +1600,8 @@ static ssize_t buffer_write (struct device *dev, struct device_attribute *attr,
         bs1 = simple_strtoul(buf, &e, 0);
 
         if (e && (!isspace(*e))) {
-                IUCV_DBF_TEXT_(setup, 2, "buffer_write: invalid char %c\n", *e);
+                IUCV_DBF_TEXT_(setup, 2, "buffer_write: invalid char %02x\n",
+                        *e);
                 return -EINVAL;
         }
         if (bs1 > NETIUCV_BUFSIZE_MAX) {
@@ -1864,7 +1928,8 @@ static void netiucv_unregister_device(struct device *dev)
  * Add it to the list of netiucv connections;
  */
 static struct iucv_connection *netiucv_new_connection(struct net_device *dev,
-                                                      char *username)
+                                                      char *username,
+                                                      char *userdata)
 {
         struct iucv_connection *conn;
 
@@ -1893,6 +1958,8 @@ static struct iucv_connection *netiucv_new_connection(struct net_device *dev,
         fsm_settimer(conn->fsm, &conn->timer);
         fsm_newstate(conn->fsm, CONN_STATE_INVALID);
 
+        if (userdata)
+                memcpy(conn->userdata, userdata, 17);
         if (username) {
                 memcpy(conn->userid, username, 9);
                 fsm_newstate(conn->fsm, CONN_STATE_STOPPED);
@@ -1919,6 +1986,7 @@ out:
  */
 static void netiucv_remove_connection(struct iucv_connection *conn)
 {
+
         IUCV_DBF_TEXT(trace, 3, __func__);
         write_lock_bh(&iucv_connection_rwlock);
         list_del_init(&conn->list);
@@ -1926,7 +1994,7 @@ static void netiucv_remove_connection(struct iucv_connection *conn)
         fsm_deltimer(&conn->timer);
         netiucv_purge_skb_queue(&conn->collect_queue);
         if (conn->path) {
-                iucv_path_sever(conn->path, iucvMagic);
+                iucv_path_sever(conn->path, conn->userdata);
                 kfree(conn->path);
                 conn->path = NULL;
         }
@@ -1985,7 +2053,7 @@ static void netiucv_setup_netdevice(struct net_device *dev)
 /**
  * Allocate and initialize everything of a net device.
  */
-static struct net_device *netiucv_init_netdevice(char *username)
+static struct net_device *netiucv_init_netdevice(char *username, char *userdata)
 {
         struct netiucv_priv *privptr;
         struct net_device *dev;
@@ -2004,7 +2072,7 @@ static struct net_device *netiucv_init_netdevice(char *username)
         if (!privptr->fsm)
                 goto out_netdev;
 
-        privptr->conn = netiucv_new_connection(dev, username);
+        privptr->conn = netiucv_new_connection(dev, username, userdata);
         if (!privptr->conn) {
                 IUCV_DBF_TEXT(setup, 2, "NULL from netiucv_new_connection\n");
                 goto out_fsm;
@@ -2022,47 +2090,31 @@ out_netdev:
 static ssize_t conn_write(struct device_driver *drv,
                           const char *buf, size_t count)
 {
-        const char *p;
         char username[9];
-        int i, rc;
+        char userdata[17];
+        int rc;
         struct net_device *dev;
         struct netiucv_priv *priv;
         struct iucv_connection *cp;
 
         IUCV_DBF_TEXT(trace, 3, __func__);
-        if (count>9) {
-                IUCV_DBF_TEXT(setup, 2, "conn_write: too long\n");
-                return -EINVAL;
-        }
-
-        for (i = 0, p = buf; i < 8 && *p; i++, p++) {
-                if (isalnum(*p) || *p == '$') {
-                        username[i] = toupper(*p);
-                        continue;
-                }
-                if (*p == '\n')
-                        /* trailing lf, grr */
-                        break;
-                IUCV_DBF_TEXT_(setup, 2,
-                               "conn_write: invalid character %c\n", *p);
-                return -EINVAL;
-        }
-        while (i < 8)
-                username[i++] = ' ';
-        username[8] = '\0';
+        rc = netiucv_check_user(buf, count, username, userdata);
+        if (rc)
+                return rc;
 
         read_lock_bh(&iucv_connection_rwlock);
         list_for_each_entry(cp, &iucv_connection_list, list) {
-                if (!strncmp(username, cp->userid, 9)) {
+                if (!strncmp(username, cp->userid, 9) &&
+                    !strncmp(userdata, cp->userdata, 17)) {
                         read_unlock_bh(&iucv_connection_rwlock);
-                        IUCV_DBF_TEXT_(setup, 2, "conn_write: Connection "
-                                "to %s already exists\n", username);
+                        IUCV_DBF_TEXT_(setup, 2, "conn_write: Connection to %s "
+                                "already exists\n", netiucv_printuser(cp));
                         return -EEXIST;
                 }
         }
         read_unlock_bh(&iucv_connection_rwlock);
 
-        dev = netiucv_init_netdevice(username);
+        dev = netiucv_init_netdevice(username, userdata);
         if (!dev) {
                 IUCV_DBF_TEXT(setup, 2, "NULL from netiucv_init_netdevice\n");
                 return -ENODEV;
@@ -2083,8 +2135,9 @@ static ssize_t conn_write(struct device_driver *drv,
         if (rc)
                 goto out_unreg;
 
-        dev_info(priv->dev, "The IUCV interface to %s has been"
-                " established successfully\n", netiucv_printname(username));
+        dev_info(priv->dev, "The IUCV interface to %s has been established "
+                            "successfully\n",
+                netiucv_printuser(priv->conn));
 
         return count;