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-rw-r--r--src/plugins/snort/dequeue.c366
1 files changed, 366 insertions, 0 deletions
diff --git a/src/plugins/snort/dequeue.c b/src/plugins/snort/dequeue.c
new file mode 100644
index 00000000000..d597b88f7a8
--- /dev/null
+++ b/src/plugins/snort/dequeue.c
@@ -0,0 +1,366 @@
+/* SPDX-License-Identifier: Apache-2.0
+ * Copyright(c) 2021 Cisco Systems, Inc.
+ */
+
+#include <vlib/vlib.h>
+#include <vnet/feature/feature.h>
+#include <snort/snort.h>
+
+typedef struct
+{
+ u32 next_index;
+ u32 sw_if_index;
+} snort_deq_trace_t;
+
+static u8 *
+format_snort_deq_trace (u8 *s, va_list *args)
+{
+ CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
+ CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
+ snort_deq_trace_t *t = va_arg (*args, snort_deq_trace_t *);
+
+ s = format (s, "snort-deq: sw_if_index %d, next index %d\n", t->sw_if_index,
+ t->next_index);
+
+ return s;
+}
+
+#define foreach_snort_deq_error \
+ _ (BAD_DESC, "bad descriptor") \
+ _ (BAD_DESC_INDEX, "bad descriptor index")
+
+typedef enum
+{
+#define _(sym, str) SNORT_DEQ_ERROR_##sym,
+ foreach_snort_deq_error
+#undef _
+ SNORT_DEQ_N_ERROR,
+} snort_deq_error_t;
+
+static char *snort_deq_error_strings[] = {
+#define _(sym, string) string,
+ foreach_snort_deq_error
+#undef _
+};
+
+static_always_inline uword
+snort_deq_instance (vlib_main_t *vm, u32 instance_index, snort_qpair_t *qp,
+ u32 *buffer_indices, u16 *nexts, u32 max_recv)
+{
+ snort_main_t *sm = &snort_main;
+ snort_per_thread_data_t *ptd =
+ vec_elt_at_index (sm->per_thread_data, vm->thread_index);
+ u32 mask = pow2_mask (qp->log2_queue_size);
+ u32 head, next, n_recv = 0, n_left;
+
+ head = __atomic_load_n (qp->deq_head, __ATOMIC_ACQUIRE);
+ next = qp->next_desc;
+
+ n_left = head - next;
+
+ if (n_left == 0)
+ return 0;
+
+ if (n_left > max_recv)
+ {
+ n_left = max_recv;
+ clib_interrupt_set (ptd->interrupts, instance_index);
+ vlib_node_set_interrupt_pending (vm, snort_deq_node.index);
+ }
+
+ while (n_left)
+ {
+ u32 desc_index, bi;
+ daq_vpp_desc_t *d;
+
+ /* check if descriptor index taken from dequqe ring is valid */
+ if ((desc_index = qp->deq_ring[next & mask]) & ~mask)
+ {
+ vlib_node_increment_counter (vm, snort_deq_node.index,
+ SNORT_DEQ_ERROR_BAD_DESC_INDEX, 1);
+ goto next;
+ }
+
+ /* check if descriptor index taken from dequeue ring points to enqueued
+ * buffer */
+ if ((bi = qp->buffer_indices[desc_index]) == ~0)
+ {
+ vlib_node_increment_counter (vm, snort_deq_node.index,
+ SNORT_DEQ_ERROR_BAD_DESC, 1);
+ goto next;
+ }
+
+ /* put descriptor back to freelist */
+ vec_add1 (qp->freelist, desc_index);
+ d = qp->descriptors + desc_index;
+ buffer_indices++[0] = bi;
+ if (d->action == DAQ_VPP_ACTION_FORWARD)
+ nexts[0] = qp->next_indices[desc_index];
+ else
+ nexts[0] = SNORT_ENQ_NEXT_DROP;
+ qp->buffer_indices[desc_index] = ~0;
+ nexts++;
+ n_recv++;
+
+ /* next */
+ next:
+ next = next + 1;
+ n_left--;
+ }
+
+ qp->next_desc = next;
+
+ return n_recv;
+}
+
+static_always_inline u32
+snort_process_all_buffer_indices (snort_qpair_t *qp, u32 *b, u16 *nexts,
+ u32 max_recv, u8 drop_on_disconnect)
+{
+ u32 *bi, n_processed = 0;
+ u32 desc_index = 0;
+
+ vec_foreach (bi, qp->buffer_indices)
+ {
+ if (n_processed >= max_recv)
+ break;
+
+ if (bi[0] == ~0)
+ continue;
+
+ desc_index = bi - qp->buffer_indices;
+
+ b[0] = bi[0];
+ if (drop_on_disconnect)
+ nexts[0] = SNORT_ENQ_NEXT_DROP;
+ else
+ nexts[0] = qp->next_indices[desc_index];
+ qp->buffer_indices[desc_index] = ~0;
+
+ nexts += 1;
+ b += 1;
+ n_processed += 1;
+ }
+ return n_processed;
+}
+
+static_always_inline uword
+snort_deq_instance_all_interrupt (vlib_main_t *vm, u32 instance_index,
+ snort_qpair_t *qp, u32 *buffer_indices,
+ u16 *nexts, u32 max_recv,
+ u8 drop_on_disconnect)
+{
+ snort_main_t *sm = &snort_main;
+ snort_per_thread_data_t *ptd =
+ vec_elt_at_index (sm->per_thread_data, vm->thread_index);
+ u32 n_processed;
+
+ n_processed = snort_process_all_buffer_indices (
+ qp, buffer_indices, nexts, max_recv, drop_on_disconnect);
+
+ if (n_processed == max_recv)
+ {
+ clib_interrupt_set (ptd->interrupts, instance_index);
+ vlib_node_set_interrupt_pending (vm, snort_deq_node.index);
+ }
+ else
+ {
+ *qp->enq_head = *qp->deq_head = qp->next_desc = 0;
+ snort_freelist_init (qp->freelist);
+ __atomic_store_n (&qp->ready, 1, __ATOMIC_RELEASE);
+ }
+
+ return n_processed;
+}
+
+static u32
+snort_deq_node_interrupt (vlib_main_t *vm, vlib_node_runtime_t *node,
+ vlib_frame_t *frame)
+{
+ snort_main_t *sm = &snort_main;
+ snort_per_thread_data_t *ptd =
+ vec_elt_at_index (sm->per_thread_data, vm->thread_index);
+ u32 buffer_indices[VLIB_FRAME_SIZE], *bi = buffer_indices;
+ u16 next_indices[VLIB_FRAME_SIZE], *nexts = next_indices;
+ u32 n_left = VLIB_FRAME_SIZE, n;
+ snort_qpair_t *qp;
+ snort_instance_t *si;
+ int inst = -1;
+
+ while ((inst = clib_interrupt_get_next (ptd->interrupts, inst)) != -1)
+ {
+ clib_interrupt_clear (ptd->interrupts, inst);
+ si = vec_elt_at_index (sm->instances, inst);
+ qp = vec_elt_at_index (si->qpairs, vm->thread_index);
+ u32 ready = __atomic_load_n (&qp->ready, __ATOMIC_ACQUIRE);
+ if (!ready)
+ n = snort_deq_instance_all_interrupt (vm, inst, qp, bi, nexts, n_left,
+ si->drop_on_disconnect);
+ else
+ n = snort_deq_instance (vm, inst, qp, bi, nexts, n_left);
+
+ n_left -= n;
+ bi += n;
+ nexts += n;
+
+ if (n_left == 0)
+ goto enq;
+ }
+
+ if (n_left == VLIB_FRAME_SIZE)
+ return 0;
+
+enq:
+ n = VLIB_FRAME_SIZE - n_left;
+ vlib_buffer_enqueue_to_next (vm, node, buffer_indices, next_indices, n);
+ return n;
+}
+
+static_always_inline uword
+snort_deq_instance_poll (vlib_main_t *vm, snort_qpair_t *qp,
+ u32 *buffer_indices, u16 *nexts, u32 max_recv)
+{
+ u32 mask = pow2_mask (qp->log2_queue_size);
+ u32 head, next, n_recv = 0, n_left;
+
+ head = __atomic_load_n (qp->deq_head, __ATOMIC_ACQUIRE);
+ next = qp->next_desc;
+
+ n_left = head - next;
+
+ if (n_left == 0)
+ return 0;
+
+ if (n_left > max_recv)
+ n_left = max_recv;
+
+ while (n_left)
+ {
+ u32 desc_index, bi;
+ daq_vpp_desc_t *d;
+
+ /* check if descriptor index taken from dequqe ring is valid */
+ if ((desc_index = qp->deq_ring[next & mask]) & ~mask)
+ {
+ vlib_node_increment_counter (vm, snort_deq_node.index,
+ SNORT_DEQ_ERROR_BAD_DESC_INDEX, 1);
+ goto next;
+ }
+
+ /* check if descriptor index taken from dequeue ring points to enqueued
+ * buffer */
+ if ((bi = qp->buffer_indices[desc_index]) == ~0)
+ {
+ vlib_node_increment_counter (vm, snort_deq_node.index,
+ SNORT_DEQ_ERROR_BAD_DESC, 1);
+ goto next;
+ }
+
+ /* put descriptor back to freelist */
+ vec_add1 (qp->freelist, desc_index);
+ d = qp->descriptors + desc_index;
+ buffer_indices++[0] = bi;
+ if (d->action == DAQ_VPP_ACTION_FORWARD)
+ nexts[0] = qp->next_indices[desc_index];
+ else
+ nexts[0] = SNORT_ENQ_NEXT_DROP;
+ qp->buffer_indices[desc_index] = ~0;
+ nexts++;
+ n_recv++;
+
+ /* next */
+ next:
+ next = next + 1;
+ n_left--;
+ }
+
+ qp->next_desc = next;
+
+ return n_recv;
+}
+
+static_always_inline uword
+snort_deq_instance_all_poll (vlib_main_t *vm, snort_qpair_t *qp,
+ u32 *buffer_indices, u16 *nexts, u32 max_recv,
+ u8 drop_on_disconnect)
+{
+ u32 n_processed = snort_process_all_buffer_indices (
+ qp, buffer_indices, nexts, max_recv, drop_on_disconnect);
+ if (n_processed < max_recv)
+ {
+ *qp->enq_head = *qp->deq_head = qp->next_desc = 0;
+ snort_freelist_init (qp->freelist);
+ __atomic_store_n (&qp->ready, 1, __ATOMIC_RELEASE);
+ }
+
+ return n_processed;
+}
+
+static u32
+snort_deq_node_polling (vlib_main_t *vm, vlib_node_runtime_t *node,
+ vlib_frame_t *frame)
+{
+ snort_main_t *sm = &snort_main;
+ u32 buffer_indices[VLIB_FRAME_SIZE], *bi = buffer_indices;
+ u16 next_indices[VLIB_FRAME_SIZE], *nexts = next_indices;
+ u32 n_left = VLIB_FRAME_SIZE, n, n_total = 0;
+ snort_qpair_t *qp;
+ snort_instance_t *si;
+
+ vec_foreach (si, sm->instances)
+ {
+ qp = vec_elt_at_index (si->qpairs, vm->thread_index);
+ u32 ready = __atomic_load_n (&qp->ready, __ATOMIC_ACQUIRE);
+ if (!ready)
+ n = snort_deq_instance_all_poll (vm, qp, bi, nexts, n_left,
+ si->drop_on_disconnect);
+ else
+ n = snort_deq_instance_poll (vm, qp, bi, nexts, n_left);
+
+ n_left -= n;
+ bi += n;
+ nexts += n;
+
+ if (n_left == 0)
+ {
+ n = VLIB_FRAME_SIZE - n_left;
+ vlib_buffer_enqueue_to_next (vm, node, buffer_indices, next_indices,
+ n);
+ n_left = VLIB_FRAME_SIZE;
+ bi = buffer_indices;
+ nexts = next_indices;
+ n_total += n;
+ }
+ }
+
+ if (n_left < VLIB_FRAME_SIZE)
+ {
+ n = VLIB_FRAME_SIZE - n_left;
+ vlib_buffer_enqueue_to_next (vm, node, buffer_indices, next_indices, n);
+ n_total += n;
+ }
+ return n_total;
+}
+
+VLIB_NODE_FN (snort_deq_node)
+(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
+{
+ snort_main_t *sm = &snort_main;
+ if (sm->input_mode == VLIB_NODE_STATE_POLLING)
+ return snort_deq_node_polling (vm, node, frame);
+ return snort_deq_node_interrupt (vm, node, frame);
+}
+
+VLIB_REGISTER_NODE (snort_deq_node) = {
+ .name = "snort-deq",
+ .vector_size = sizeof (u32),
+ .format_trace = format_snort_deq_trace,
+ .type = VLIB_NODE_TYPE_INPUT,
+ .state = VLIB_NODE_STATE_DISABLED,
+ .sibling_of = "snort-enq",
+
+ .n_errors = ARRAY_LEN (snort_deq_error_strings),
+ .error_strings = snort_deq_error_strings,
+
+ .n_next_nodes = 0,
+};