packets: New function eth_from_hex().

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Signed-off-by: Ben Pfaff <blp@nicira.com>

diff --git a/lib/packets.c b/lib/packets.c
index 46a44bd..b9f37bb 100644 (file)
--- a/lib/packets.c
+++ b/lib/packets.c
@@ -121,6 +121,31 @@ eth_pop_vlan(struct ofpbuf *packet)
     }
 }
 
+/* Converts hex digits in 'hex' to an Ethernet packet in '*packetp'.  The
+ * caller must free '*packetp'.  On success, returns NULL.  On failure, returns
+ * an error message and stores NULL in '*packetp'. */
+const char *
+eth_from_hex(const char *hex, struct ofpbuf **packetp)
+{
+    struct ofpbuf *packet;
+
+    packet = *packetp = ofpbuf_new(strlen(hex) / 2);
+
+    if (ofpbuf_put_hex(packet, hex, NULL)[0] != '\0') {
+        ofpbuf_delete(packet);
+        *packetp = NULL;
+        return "Trailing garbage in packet data";
+    }
+
+    if (packet->size < ETH_HEADER_LEN) {
+        ofpbuf_delete(packet);
+        *packetp = NULL;
+        return "Packet data too short for Ethernet";
+    }
+
+    return NULL;
+}
+
 /* Given the IP netmask 'netmask', returns the number of bits of the IP address
  * that it specifies, that is, the number of 1-bits in 'netmask'.  'netmask'
  * must be a CIDR netmask (see ip_is_cidr()). */

diff --git a/lib/packets.h b/lib/packets.h
index 439a7dd..9e283a5 100644 (file)
--- a/lib/packets.h
+++ b/lib/packets.h
@@ -134,6 +134,8 @@ void compose_benign_packet(struct ofpbuf *, const char *tag,
 void eth_push_vlan(struct ofpbuf *, ovs_be16 tci);
 void eth_pop_vlan(struct ofpbuf *);
 
+const char *eth_from_hex(const char *hex, struct ofpbuf **packetp);
+
 /* Example:
  *
  * uint8_t mac[ETH_ADDR_LEN];

diff --git a/ofproto/ofproto-dpif.c b/ofproto/ofproto-dpif.c
index fd0cc67..7dc8cae 100644 (file)
--- a/ofproto/ofproto-dpif.c
+++ b/ofproto/ofproto-dpif.c
@@ -5738,15 +5738,11 @@ ofproto_unixctl_trace(struct unixctl_conn *conn, int argc, const char *argv[],
         uint16_t in_port = ofp_port_to_odp_port(atoi(in_port_s));
         ovs_be64 tun_id = htonll(strtoull(tun_id_s, NULL, 0));
         uint32_t priority = atoi(priority_s);
+        const char *msg;
 
-        packet = ofpbuf_new(strlen(packet_s) / 2);
-        if (ofpbuf_put_hex(packet, packet_s, NULL)[0] != '\0') {
-            unixctl_command_reply(conn, 501, "Trailing garbage in command");
-            goto exit;
-        }
-        if (packet->size < ETH_HEADER_LEN) {
-            unixctl_command_reply(conn, 501,
-                                  "Packet data too short for Ethernet");
+        msg = eth_from_hex(packet_s, &packet);
+        if (msg) {
+            unixctl_command_reply(conn, 501, msg);
             goto exit;
         }