Extended 'struct packet_dyn' with proto fields which has
dynamically changing values at runtime.
Implement incrementing of proto field at runtime with min & max
parameters, by default if the 'min' parameter is not specified
then original value is used. For fields which len is greater
than 4 - last 4 bytes are incremented as unsigned int value (this
trick is used for increment MAC/IPv6 addresses).
Added 'field_changed' callback for proto header which
may be used for check if csum updating is needed. This callback
is called after field was changed at runtime.
Added 'packet_update' callback to let proto header know
when to apply final proto header changes at runtime (csum update).
Signed-off-by: Vadim Kochan <vadi...@gmail.com>
---
trafgen.c | 9 +++++++
trafgen_conf.h | 7 +++++
trafgen_proto.c | 84 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
trafgen_proto.h | 26 ++++++++++++++++++
4 files changed, 126 insertions(+)
diff --git a/trafgen.c b/trafgen.c
index b76b5d7..553dfa5 100644
--- a/trafgen.c
+++ b/trafgen.c
@@ -619,6 +619,15 @@ static inline void packet_apply_dyn_elements(int idx)
apply_randomizer(idx);
apply_csum16(idx);
}
+
+ if (packet_dyn_has_fields(&packet_dyn[idx])) {
+ uint32_t i;
+
+ for (i = 0; i < packet_dyn[idx].flen; i++)
+ proto_field_dyn_apply(packet_dyn[idx].fields[i]);
+
+ proto_packet_update(idx);
+ }
}
static void xmit_slowpath_or_die(struct ctx *ctx, unsigned int cpu, unsigned
long orig_num)
diff --git a/trafgen_conf.h b/trafgen_conf.h
index 934f8fe..7f3616c 100644
--- a/trafgen_conf.h
+++ b/trafgen_conf.h
@@ -49,6 +49,8 @@ struct packet_dyn {
size_t rlen;
struct csum16 *csum;
size_t slen;
+ struct proto_field **fields;
+ uint32_t flen;
};
static inline bool packet_dyn_has_elems(struct packet_dyn *p)
@@ -61,6 +63,11 @@ static inline bool packet_dyn_has_only_csums(struct
packet_dyn *p)
return (p->clen == 0 && p->rlen == 0 && p->slen);
}
+static inline bool packet_dyn_has_fields(struct packet_dyn *p)
+{
+ return !!p->flen;
+}
+
extern void compile_packets_str(char *str, bool verbose, unsigned int cpu);
extern void compile_packets(char *file, bool verbose, unsigned int cpu,
bool invoke_cpp, char *const cpp_argv[]);
diff --git a/trafgen_proto.c b/trafgen_proto.c
index 4219794..72dbad3 100644
--- a/trafgen_proto.c
+++ b/trafgen_proto.c
@@ -407,6 +407,19 @@ void protos_init(const char *dev)
protos_l4_init();
}
+void proto_packet_update(uint32_t idx)
+{
+ struct packet *pkt = packet_get(idx);
+ ssize_t i;
+
+ for (i = pkt->headers_count - 1; i >= 0; i--) {
+ struct proto_hdr *hdr = pkt->headers[i];
+
+ if (hdr->packet_update)
+ hdr->packet_update(hdr);
+ }
+}
+
void proto_packet_finish(void)
{
struct proto_hdr **headers = current_packet()->headers;
@@ -421,3 +434,74 @@ void proto_packet_finish(void)
p->packet_finish(p);
}
}
+
+static inline unsigned int field_inc(struct proto_field *field)
+{
+ uint32_t min = field->func.min;
+ uint32_t max = field->func.max;
+ uint32_t val = field->func.val;
+ uint32_t inc = field->func.inc;
+ uint32_t next;
+
+ next = (val + inc) % (max + 1);
+ field->func.val = max(next, min);
+
+ return val;
+}
+
+static void field_inc_func(struct proto_field *field)
+{
+ if (field->len == 1) {
+ proto_field_set_u8(field->hdr, field->id, field_inc(field));
+ } else if (field->len == 2) {
+ proto_field_set_be16(field->hdr, field->id, field_inc(field));
+ } else if (field->len == 4) {
+ proto_field_set_be32(field->hdr, field->id, field_inc(field));
+ } else if (field->len > 4) {
+ uint8_t *bytes = __proto_field_get_bytes(field);
+
+ bytes += field->len - 4;
+
+ *(uint32_t *)bytes = bswap_32(field_inc(field));
+ }
+}
+
+void proto_field_func_add(struct proto_hdr *hdr, uint32_t fid,
+ struct proto_field_func *func)
+{
+ struct proto_field *field = proto_field_by_id(hdr, fid);
+
+ bug_on(!func);
+
+ memcpy(&field->func, func, sizeof(*func));
+
+ field->func.max = field->func.max ?: UINT32_MAX - 1;
+
+ if (func->type & PROTO_FIELD_FUNC_INC) {
+ if (func->type & PROTO_FIELD_FUNC_MIN)
+ field->func.val = func->min;
+ else if (field->len == 1)
+ field->func.val = proto_field_get_u8(hdr, fid);
+ else if (field->len == 2)
+ field->func.val = proto_field_get_u16(hdr, fid);
+ else if (field->len == 4)
+ field->func.val = proto_field_get_u32(hdr, fid);
+ else if (field->len > 4) {
+ uint8_t *bytes = __proto_field_get_bytes(field);
+
+ bytes += field->len - 4;
+ field->func.val = bswap_32(*(uint32_t *)bytes);
+ }
+
+ field->func.update_field = field_inc_func;
+ }
+}
+
+void proto_field_dyn_apply(struct proto_field *field)
+{
+ if (field->func.update_field)
+ field->func.update_field(field);
+
+ if (field->hdr->field_changed)
+ field->hdr->field_changed(field->hdr, field);
+}
diff --git a/trafgen_proto.h b/trafgen_proto.h
index dbba700..2b48c68 100644
--- a/trafgen_proto.h
+++ b/trafgen_proto.h
@@ -27,8 +27,24 @@ enum proto_layer {
PROTO_L4,
};
+struct proto_field;
struct proto_hdr;
+enum proto_field_func_t {
+ PROTO_FIELD_FUNC_INC = 1 << 0,
+ PROTO_FIELD_FUNC_MIN = 1 << 1,
+};
+
+struct proto_field_func {
+ enum proto_field_func_t type;
+ uint32_t min;
+ uint32_t max;
+ int32_t inc;
+ uint32_t val;
+
+ void (* update_field)(struct proto_field *field);
+};
+
struct proto_field {
uint32_t id;
size_t len;
@@ -37,6 +53,7 @@ struct proto_field {
/* might be negative (e.g. VLAN TPID field) */
int16_t offset;
+ struct proto_field_func func;
bool is_set;
uint16_t pkt_offset;
struct proto_hdr *hdr;
@@ -55,7 +72,9 @@ struct proto_hdr {
void (*header_init)(struct proto_hdr *hdr);
void (*header_finish)(struct proto_hdr *hdr);
+ void (*field_changed)(struct proto_hdr *hdr, struct proto_field *field);
void (*packet_finish)(struct proto_hdr *hdr);
+ void (*packet_update)(struct proto_hdr *hdr);
void (*set_next_proto)(struct proto_hdr *hdr, enum proto_id pid);
};
@@ -65,6 +84,8 @@ extern void proto_header_register(struct proto_hdr *hdr);
extern struct proto_hdr *proto_header_init(enum proto_id pid);
extern void proto_header_finish(struct proto_hdr *hdr);
extern void proto_packet_finish(void);
+extern void proto_packet_update(uint32_t idx);
+
extern struct proto_hdr *proto_lower_default_add(struct proto_hdr *hdr,
enum proto_id pid);
@@ -111,4 +132,9 @@ extern void proto_field_set_default_dev_ipv4(struct
proto_hdr *hdr, uint32_t fid
extern void proto_field_set_dev_ipv6(struct proto_hdr *hdr, uint32_t fid);
extern void proto_field_set_default_dev_ipv6(struct proto_hdr *hdr, uint32_t
fid);
+extern void proto_field_dyn_apply(struct proto_field *field);
+
+extern void proto_field_func_add(struct proto_hdr *hdr, uint32_t fid,
+ struct proto_field_func *func);
+
#endif /* TRAFGEN_PROTO_H */
--
2.9.2
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