Openvswitch原理与代码分析(8): 修改Openvswitch代码添加自定义action

有时候我们需要自定义一些自己的action，根据包头里面的信息，做一些自己的操作。

例如添加一个action名为handle_example

第一、修改ofp-actions.c文件

首先在ofp-actions.c里面添加Openflow各个版本的这个action

static
const
struct ofpact_map *
get_ofpact_map(enum ofp_version version)
{
????/* OpenFlow 1.0 actions. */
????static
const
struct ofpact_map of10[] = {
????????{ OFPACT_OUTPUT, 0 },
????????{ OFPACT_SET_VLAN_VID, 1 },
????????{ OFPACT_SET_VLAN_PCP, 2 },
????????{ OFPACT_STRIP_VLAN, 3 },
????????{ OFPACT_SET_ETH_SRC, 4 },
????????{ OFPACT_SET_ETH_DST, 5 },
????????{ OFPACT_SET_IPV4_SRC, 6 },
????????{ OFPACT_SET_IPV4_DST, 7 },
????????{ OFPACT_SET_IP_DSCP, 8 },
????????{ OFPACT_SET_L4_SRC_PORT, 9 },
????????{ OFPACT_SET_L4_DST_PORT, 10 },
????????{ OFPACT_ENQUEUE, 11 },
????????{ OFPACT_HANDLE_EXAMPLE, 28 },
????????{ 0, -1 },
????};
?
????/* OpenFlow 1.1 actions. */
????static
const
struct ofpact_map of11[] = {
????????{ OFPACT_OUTPUT, 0 },
????????{ OFPACT_SET_VLAN_VID, 1 },
????????{ OFPACT_SET_VLAN_PCP, 2 },
????????{ OFPACT_SET_ETH_SRC, 3 },
????????{ OFPACT_SET_ETH_DST, 4 },
????????{ OFPACT_SET_IPV4_SRC, 5 },
????????{ OFPACT_SET_IPV4_DST, 6 },
????????{ OFPACT_SET_IP_DSCP, 7 },
????????{ OFPACT_SET_IP_ECN, 8 },
????????{ OFPACT_SET_L4_SRC_PORT, 9 },
????????{ OFPACT_SET_L4_DST_PORT, 10 },
????????/* OFPAT_COPY_TTL_OUT (11) not supported. */
????????/* OFPAT_COPY_TTL_IN (12) not supported. */
????????{ OFPACT_SET_MPLS_LABEL, 13 },
????????{ OFPACT_SET_MPLS_TC, 14 },
????????{ OFPACT_SET_MPLS_TTL, 15 },
????????{ OFPACT_DEC_MPLS_TTL, 16 },
????????{ OFPACT_PUSH_VLAN, 17 },
????????{ OFPACT_STRIP_VLAN, 18 },
????????{ OFPACT_PUSH_MPLS, 19 },
????????{ OFPACT_POP_MPLS, 20 },
????????{ OFPACT_SET_QUEUE, 21 },
????????{ OFPACT_GROUP, 22 },
????????{ OFPACT_SET_IP_TTL, 23 },
????????{ OFPACT_DEC_TTL, 24 },
????????{ OFPACT_HANDLE_EXAMPLE, 28 },
????????{ 0, -1 },
????};
?
????/* OpenFlow 1.2, 1.3, and 1.4 actions. */
????static
const
struct ofpact_map of12[] = {
????????{ OFPACT_OUTPUT, 0 },
????????/* OFPAT_COPY_TTL_OUT (11) not supported. */
????????/* OFPAT_COPY_TTL_IN (12) not supported. */
????????{ OFPACT_SET_MPLS_TTL, 15 },
????????{ OFPACT_DEC_MPLS_TTL, 16 },
????????{ OFPACT_PUSH_VLAN, 17 },
????????{ OFPACT_STRIP_VLAN, 18 },
????????{ OFPACT_PUSH_MPLS, 19 },
????????{ OFPACT_POP_MPLS, 20 },
????????{ OFPACT_SET_QUEUE, 21 },
????????{ OFPACT_GROUP, 22 },
????????{ OFPACT_SET_IP_TTL, 23 },
????????{ OFPACT_DEC_TTL, 24 },
????????{ OFPACT_SET_FIELD, 25 },
????????/* OF1.3+ OFPAT_PUSH_PBB (26) not supported. */
????????/* OF1.3+ OFPAT_POP_PBB (27) not supported. */
????????{ OFPACT_HANDLE_EXAMPLE, 28 },
????????{ 0, -1 },
????};
?
????switch (version) {
????case OFP10_VERSION:
????????return of10;
?
????case OFP11_VERSION:
????????return of11;
?
????case OFP12_VERSION:
????case OFP13_VERSION:
????case OFP14_VERSION:
????case OFP15_VERSION:
????default:
????????return of12;
????}
}

其次添加raw action type

enum ofp_raw_action_type {
/* ## ----------------- ## */
/* ## Standard actions. ## */
/* ## ----------------- ## */
?
????/* OF1.0(0): struct ofp10_action_output. */
????OFPAT_RAW10_OUTPUT,
????/* OF1.1+(0): struct ofp11_action_output. */
????OFPAT_RAW11_OUTPUT,
?
????/* OF1.0(1): uint16_t. */
????OFPAT_RAW10_SET_VLAN_VID,
????/* OF1.0(2): uint8_t. */
????OFPAT_RAW10_SET_VLAN_PCP,
?
????/* OF1.1(1), OF1.2+(1) is deprecated (use Set-Field): uint16_t.
?????*
?????* [Semantics differ slightly between the 1.0 and 1.1 versions of the VLAN
?????* modification actions: the 1.0 versions push a VLAN header if none is
?????* present, but the 1.1 versions do not. That is the only reason that we
?????* distinguish their raw action types.] */
????OFPAT_RAW11_SET_VLAN_VID,
????/* OF1.1(2), OF1.2+(2) is deprecated (use Set-Field): uint8_t. */
????OFPAT_RAW11_SET_VLAN_PCP,
?
????/* OF1.1+(17): ovs_be16.
?????*
?????* [The argument is the Ethertype, e.g. ETH_TYPE_VLAN_8021Q, not the VID or
?????* TCI.] */
????OFPAT_RAW11_PUSH_VLAN,
?
????/* OF1.0(3): void. */
????OFPAT_RAW10_STRIP_VLAN,
????/* OF1.1+(18): void. */
????OFPAT_RAW11_POP_VLAN,
?
????/* OF1.0(4), OF1.1(3), OF1.2+(3) is deprecated (use Set-Field): struct
?????* ofp_action_dl_addr. */
????OFPAT_RAW_SET_DL_SRC,
?
????/* OF1.0(5), OF1.1(4), OF1.2+(4) is deprecated (use Set-Field): struct
?????* ofp_action_dl_addr. */
????OFPAT_RAW_SET_DL_DST,
?
????/* OF1.0(6), OF1.1(5), OF1.2+(5) is deprecated (use Set-Field):
?????* ovs_be32. */
????OFPAT_RAW_SET_NW_SRC,
?
????/* OF1.0(7), OF1.1(6), OF1.2+(6) is deprecated (use Set-Field):
?????* ovs_be32. */
????OFPAT_RAW_SET_NW_DST,
?
????/* OF1.0(8), OF1.1(7), OF1.2+(7) is deprecated (use Set-Field): uint8_t. */
????OFPAT_RAW_SET_NW_TOS,
?
????/* OF1.1(8), OF1.2+(8) is deprecated (use Set-Field): uint8_t. */
????OFPAT_RAW11_SET_NW_ECN,
?
????/* OF1.0(9), OF1.1(9), OF1.2+(9) is deprecated (use Set-Field):
?????* ovs_be16. */
????OFPAT_RAW_SET_TP_SRC,
?
????/* OF1.0(10), OF1.1(10), OF1.2+(10) is deprecated (use Set-Field):
?????* ovs_be16. */
????OFPAT_RAW_SET_TP_DST,
?
????/* OF1.0(11): struct ofp10_action_enqueue. */
????OFPAT_RAW10_ENQUEUE,
?
????/* NX1.0(30), OF1.1(13), OF1.2+(13) is deprecated (use Set-Field):
?????* ovs_be32. */
????OFPAT_RAW_SET_MPLS_LABEL,
?
????/* NX1.0(31), OF1.1(14), OF1.2+(14) is deprecated (use Set-Field):
?????* uint8_t. */
????OFPAT_RAW_SET_MPLS_TC,
?
????/* NX1.0(25), OF1.1(15), OF1.2+(15) is deprecated (use Set-Field):
?????* uint8_t. */
????OFPAT_RAW_SET_MPLS_TTL,
?
????/* NX1.0(26), OF1.1+(16): void. */
????OFPAT_RAW_DEC_MPLS_TTL,
?
????/* NX1.0(23), OF1.1+(19): ovs_be16.
?????*
?????* [The argument is the Ethertype, e.g. ETH_TYPE_MPLS, not the label.] */
????OFPAT_RAW_PUSH_MPLS,
?
????/* NX1.0(24), OF1.1+(20): ovs_be16.
?????*
?????* [The argument is the Ethertype, e.g. ETH_TYPE_IPV4 if at BoS or
?????* ETH_TYPE_MPLS otherwise, not the label.] */
????OFPAT_RAW_POP_MPLS,
?
????/* NX1.0(4), OF1.1+(21): uint32_t. */
????OFPAT_RAW_SET_QUEUE,
?
????/* OF1.1+(22): uint32_t. */
????OFPAT_RAW11_GROUP,
?
????/* OF1.1+(23): uint8_t. */
????OFPAT_RAW11_SET_NW_TTL,
?
????/* NX1.0(18), OF1.1+(24): void. */
????OFPAT_RAW_DEC_NW_TTL,
????/* NX1.0+(21): struct nx_action_cnt_ids, ... */
????NXAST_RAW_DEC_TTL_CNT_IDS,
?
????/* OF1.2-1.4(25): struct ofp12_action_set_field, ... */
????OFPAT_RAW12_SET_FIELD,
????/* OF1.5+(25): struct ofp12_action_set_field, ... */
????OFPAT_RAW15_SET_FIELD,
?
????/* OF1.0(28): void. */
????OFPAT_RAW10_HANDLE_EXAMPLE,
?
????/* OF1.1(28): void. */
????OFPAT_RAW11_HANDLE_EXAMPLE,
?
????/* OF1.2-1.4(28): void. */
????OFPAT_RAW12_HANDLE_EXAMPLE,
?
????/* NX1.0-1.4(7): struct nx_action_reg_load.
?????*
?????* [In OpenFlow 1.5, set_field is a superset of reg_load functionality, so
?????* we drop reg_load.] */
????NXAST_RAW_REG_LOAD,
????/* NX1.0-1.4(33): struct nx_action_reg_load2, ...
?????*
?????* [In OpenFlow 1.5, set_field is a superset of reg_load2 functionality, so
?????* we drop reg_load2.] */
????NXAST_RAW_REG_LOAD2,
?
????/* OF1.5+(28): struct ofp15_action_copy_field, ... */
????OFPAT_RAW15_COPY_FIELD,
????/* ONF1.3-1.4(3200): struct onf_action_copy_field, ... */
????ONFACT_RAW13_COPY_FIELD,
????/* NX1.0-1.4(6): struct nx_action_reg_move, ... */
????NXAST_RAW_REG_MOVE,
?
/* ## ------------------------- ## */
/* ## Nicira extension actions. ## */
/* ## ------------------------- ## */
?
/* Actions similar to standard actions are listed with the standard actions. */
?
????/* NX1.0+(1): uint16_t. */
????NXAST_RAW_RESUBMIT,
????/* NX1.0+(14): struct nx_action_resubmit. */
????NXAST_RAW_RESUBMIT_TABLE,
?
????/* NX1.0+(2): uint32_t. */
????NXAST_RAW_SET_TUNNEL,
????/* NX1.0+(9): uint64_t. */
????NXAST_RAW_SET_TUNNEL64,
?
????/* NX1.0+(5): void. */
????NXAST_RAW_POP_QUEUE,
?
????/* NX1.0+(8): struct nx_action_note, ... */
????NXAST_RAW_NOTE,
?
????/* NX1.0+(10): struct nx_action_multipath. */
????NXAST_RAW_MULTIPATH,
?
????/* NX1.0+(12): struct nx_action_bundle, ... */
????NXAST_RAW_BUNDLE,
????/* NX1.0+(13): struct nx_action_bundle, ... */
????NXAST_RAW_BUNDLE_LOAD,
?
????/* NX1.0+(15): struct nx_action_output_reg. */
????NXAST_RAW_OUTPUT_REG,
????/* NX1.0+(32): struct nx_action_output_reg2. */
????NXAST_RAW_OUTPUT_REG2,
?
????/* NX1.0+(16): struct nx_action_learn, ... */
????NXAST_RAW_LEARN,
?
????/* NX1.0+(17): void. */
????NXAST_RAW_EXIT,
?
????/* NX1.0+(19): struct nx_action_fin_timeout. */
????NXAST_RAW_FIN_TIMEOUT,
?
????/* NX1.0+(20): struct nx_action_controller. */
????NXAST_RAW_CONTROLLER,
?
????/* NX1.0+(22): struct nx_action_write_metadata. */
????NXAST_RAW_WRITE_METADATA,
?
????/* NX1.0+(27): struct nx_action_stack. */
????NXAST_RAW_STACK_PUSH,
?
????/* NX1.0+(28): struct nx_action_stack. */
????NXAST_RAW_STACK_POP,
?
????/* NX1.0+(29): struct nx_action_sample. */
????NXAST_RAW_SAMPLE,
?
????/* NX1.0+(34): struct nx_action_conjunction. */
????NXAST_RAW_CONJUNCTION,
?
????/* NX1.0+(35): struct nx_action_conntrack, ... */
????NXAST_RAW_CT,
?
/* ## ------------------ ## */
/* ## Debugging actions. ## */
/* ## ------------------ ## */
?
/* These are intentionally undocumented, subject to change, and ovs-vswitchd */
/* accepts them only if started with --enable-dummy. */
?
????/* NX1.0+(255): void. */
????NXAST_RAW_DEBUG_RECIRC,
};

第三，添加handle example的action的处理函数

/* handle gtp actions. */
static
enum ofperr
decode_OFPAT_RAW10_HANDLE_EXAMPLE(struct ofpbuf *out)
{
????ofpact_put_HANDLE_EXAMPLE(out)->ofpact.raw = OFPAT_RAW10_HANDLE_EXAMPLE;
????return 0;
}
?
static
enum ofperr
decode_OFPAT_RAW11_HANDLE_EXAMPLE(struct ofpbuf *out)
{
????ofpact_put_HANDLE_EXAMPLE(out)->ofpact.raw = OFPAT_RAW11_HANDLE_EXAMPLE;
????return 0;
}
?
static
enum ofperr
decode_OFPAT_RAW12_HANDLE_EXAMPLE(struct ofpbuf *out)
{
????ofpact_put_HANDLE_EXAMPLE(out)->ofpact.raw = OFPAT_RAW12_HANDLE_EXAMPLE;
????return 0;
}
?
static
void
encode_HANDLE_EXAMPLE(const
struct ofpact_null *null OVS_UNUSED,
??????????????????enum ofp_version ofp_version, struct ofpbuf *out)
{
????if (ofp_version == OFP10_VERSION) {
????????put_OFPAT10_HANDLE_EXAMPLE(out);
????} else
if (ofp_version == OFP11_VERSION) {
????????put_OFPAT11_HANDLE_EXAMPLE(out);
????} else {
????????put_OFPAT12_HANDLE_EXAMPLE(out);
????}
}
?
static
char * OVS_WARN_UNUSED_RESULT
parse_HANDLE_EXAMPLE(char *arg OVS_UNUSED, struct ofpbuf *ofpacts,
?????????????????enum ofputil_protocol *usable_protocols OVS_UNUSED)
{
????ofpact_put_HANDLE_EXAMPLE(ofpacts)->ofpact.raw = OFPAT_RAW10_HANDLE_EXAMPLE;
????return NULL;
}
?
static
void
format_HANDLE_EXAMPLE(const
struct ofpact_null *a OVS_UNUSED, struct ds *s)
{
????ds_put_cstr(s, "handle_example");
}

struct ofpact *
ofpact_next_flattened(const
struct ofpact *ofpact)
{
switch (ofpact->type) {
case OFPACT_HANDLE_EXAMPLE:

static
bool
ofpact_is_set_or_move_action(const
struct ofpact *a)
{
????switch (a->type) {
????case OFPACT_HANDLE_EXAMPLE:
return true;

static
bool
ofpact_is_allowed_in_actions_set(const
struct ofpact *a)
{
????switch (a->type) {
????case OFPACT_HANDLE_EXAMPLE:
return true;

enum ovs_instruction_type
ovs_instruction_type_from_ofpact_type(enum ofpact_type type)
{
????switch (type) {
????case OFPACT_HANDLE_EXAMPLE:

static
enum ofperr
ofpact_check__(enum ofputil_protocol *usable_protocols, struct ofpact *a,
???????????????struct flow *flow, ofp_port_t max_ports,
???????????????uint8_t table_id, uint8_t n_tables)
{
????const
struct ofpact_enqueue *enqueue;
????const
struct mf_field *mf;
?
????switch (a->type) {
????case OFPACT_HANDLE_EXAMPLE:
????????return 0;

static
bool
ofpact_outputs_to_port(const
struct ofpact *ofpact, ofp_port_t port)
{
????switch (ofpact->type) {
????case OFPACT_HANDLE_EXAMPLE:
????default:
????????return
false;

第二，修改文件ofp-actions.h

#define OFPACTS
????/* Output. */
????OFPACT(OUTPUT, ofpact_output, ofpact, "output")
????OFPACT(GROUP, ofpact_group, ofpact, "group")
????OFPACT(CONTROLLER, ofpact_controller, ofpact, "controller")
????OFPACT(ENQUEUE, ofpact_enqueue, ofpact, "enqueue")
????OFPACT(OUTPUT_REG, ofpact_output_reg, ofpact, "output_reg")
????OFPACT(BUNDLE, ofpact_bundle, slaves, "bundle")
????????????????????????????????????????????????????????????????????????
????/* Header changes. */
????OFPACT(SET_FIELD, ofpact_set_field, ofpact, "set_field")
????OFPACT(HANDLE_EXAMPLE, ofpact_null, ofpact, "handle_example")
????OFPACT(SET_VLAN_VID, ofpact_vlan_vid, ofpact, "set_vlan_vid")
????OFPACT(SET_VLAN_PCP, ofpact_vlan_pcp, ofpact, "set_vlan_pcp")
????OFPACT(STRIP_VLAN, ofpact_null, ofpact, "strip_vlan")
????OFPACT(PUSH_VLAN, ofpact_null, ofpact, "push_vlan")
????OFPACT(SET_ETH_SRC, ofpact_mac, ofpact, "mod_dl_src")
????OFPACT(SET_ETH_DST, ofpact_mac, ofpact, "mod_dl_dst")
????OFPACT(SET_IPV4_SRC, ofpact_ipv4, ofpact, "mod_nw_src")
????OFPACT(SET_IPV4_DST, ofpact_ipv4, ofpact, "mod_nw_dst")
????OFPACT(SET_IP_DSCP, ofpact_dscp, ofpact, "mod_nw_tos")
????OFPACT(SET_IP_ECN, ofpact_ecn, ofpact, "mod_nw_ecn")
????OFPACT(SET_IP_TTL, ofpact_ip_ttl, ofpact, "mod_nw_ttl")
????OFPACT(SET_L4_SRC_PORT, ofpact_l4_port, ofpact, "mod_tp_src")
????OFPACT(SET_L4_DST_PORT, ofpact_l4_port, ofpact, "mod_tp_dst")
????OFPACT(REG_MOVE, ofpact_reg_move, ofpact, "move")
????OFPACT(STACK_PUSH, ofpact_stack, ofpact, "push")
????OFPACT(STACK_POP, ofpact_stack, ofpact, "pop")
????OFPACT(DEC_TTL, ofpact_cnt_ids, cnt_ids, "dec_ttl")
????OFPACT(SET_MPLS_LABEL, ofpact_mpls_label, ofpact, "set_mpls_label")
????OFPACT(SET_MPLS_TC, ofpact_mpls_tc, ofpact, "set_mpls_tc")
????OFPACT(SET_MPLS_TTL, ofpact_mpls_ttl, ofpact, "set_mpls_ttl")
????OFPACT(DEC_MPLS_TTL, ofpact_null, ofpact, "dec_mpls_ttl")
????OFPACT(PUSH_MPLS, ofpact_push_mpls, ofpact, "push_mpls")
????OFPACT(POP_MPLS, ofpact_pop_mpls, ofpact, "pop_mpls")
????????????????????????????????????????????????????????????????????????
????/* Metadata. */
????OFPACT(SET_TUNNEL, ofpact_tunnel, ofpact, "set_tunnel")
????OFPACT(SET_QUEUE, ofpact_queue, ofpact, "set_queue")
????OFPACT(POP_QUEUE, ofpact_null, ofpact, "pop_queue")
????OFPACT(FIN_TIMEOUT, ofpact_fin_timeout, ofpact, "fin_timeout")
????????????????????????????????????????????????????????????????????????
????/* Flow table interaction. */
????OFPACT(RESUBMIT, ofpact_resubmit, ofpact, "resubmit")
????OFPACT(LEARN, ofpact_learn, specs, "learn")
????OFPACT(CONJUNCTION, ofpact_conjunction, ofpact, "conjunction")
????????????????????????????????????????????????????????????????????????
????/* Arithmetic. */
????OFPACT(MULTIPATH, ofpact_multipath, ofpact, "multipath")
????????????????????????????????????????????????????????????????????????
????/* Other. */
????OFPACT(NOTE, ofpact_note, data, "note")
????OFPACT(EXIT, ofpact_null, ofpact, "exit")
????OFPACT(SAMPLE, ofpact_sample, ofpact, "sample")
????OFPACT(UNROLL_XLATE, ofpact_unroll_xlate, ofpact, "unroll_xlate")
????OFPACT(CT, ofpact_conntrack, ofpact, "ct")
????????????????????????????????????????????????????????????????????????
????/* Debugging actions.
?????*
?????* These are intentionally undocumented, subject to change, and
?????* only accepted if ovs-vswitchd is started with --enable-dummy. */
????OFPACT(DEBUG_RECIRC, ofpact_null, ofpact, "debug_recirc")
????????????????????????????????????????????????????????????????????????
????/* Instructions. */
????OFPACT(METER, ofpact_meter, ofpact, "meter")
????OFPACT(CLEAR_ACTIONS, ofpact_null, ofpact, "clear_actions")
????OFPACT(WRITE_ACTIONS, ofpact_nest, ofpact, "write_actions")
????OFPACT(WRITE_METADATA, ofpact_metadata, ofpact, "write_metadata")
????OFPACT(GOTO_TABLE, ofpact_goto_table, ofpact, "goto_table")

第三、修改ofproto\ofproto-dpif-xlate.c文件

static
void
recirc_unroll_actions(const
struct ofpact *ofpacts, size_t ofpacts_len,
??????????????????????struct xlate_ctx *ctx)
{
????const
struct ofpact *a;
?
????OFPACT_FOR_EACH (a, ofpacts, ofpacts_len) {
????????switch (a->type) {
????????case OFPACT_OPERATE_EXAMPLE:
????????????/* These may not generate PACKET INs. */
????????????break;

static
void
do_xlate_actions(const
struct ofpact *ofpacts, size_t ofpacts_len,
?????????????????struct xlate_ctx *ctx)
{
????struct flow_wildcards *wc = ctx->wc;
????struct flow *flow = &ctx->xin->flow;
????const
struct ofpact *a;
?
????if (ovs_native_tunneling_is_on(ctx->xbridge->ofproto)) {
????????tnl_neigh_snoop(flow, wc, ctx->xbridge->name);
????}
????/* dl_type already in the mask, not set below. */
?
????OFPACT_FOR_EACH (a, ofpacts, ofpacts_len) {
????????struct ofpact_controller *controller;
????????const
struct ofpact_metadata *metadata;
????????const
struct ofpact_set_field *set_field;
????????const
struct mf_field *mf;
?
????????if (ctx->error) {
????????????break;
????????}
?
????????if (ctx->exit) {
????????????/* Check if need to store the remaining actions for later
?????????????* execution. */
????????????if (exit_recirculates(ctx)) {
????????????????recirc_unroll_actions(a, OFPACT_ALIGN(ofpacts_len -
??????????????????????????????????????????????????????((uint8_t *)a -
???????????????????????????????????????????????????????(uint8_t *)ofpacts)),
??????????????????????????????????????ctx);
????????????}
????????????break;
????????}
?
????????switch (a->type) {
???case OFPACT_HANDLE_EXAMPLE:
????????????VLOG_INFO("OFPACT_HANDLE_EXAMPLE");
????????????CHECK_MPLS_RECIRCULATION();
????????????handle_example(flow, wc, ctx->xin->packet, ctx);
????????????break;

最最重要的就是handle_example的实现，为你自己实现的逻辑，对于包头的修改可以通过修改flow来进行，也可以进一步解析ctx->xin->packet，也即解析网络包的正文。

时间： 2024-10-05 01:28:49

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