UserCalls
This sample demonstrates how to provide application functions for use by VM containers.
- Declare calls
This sample provides three application calls:
int bpf_user_get_magic(); void bpf_user_set_magic(int value); size_t bpf_user_send_packet(char* data, size_t len) \ size_t bpf_user_read_packet(char* buffer, size_t len)
These are declared using the
BPF_SYSCALL_APP
macro.The
include/bpf_appcalls.h
must be provided in the container directory.
- Implement calls
The application must provide implementations for the declared functions in the
rBPF::VM
namespace. Implementations are identical to the VM calls but with an additional pointer to the VM :cpp:typedef:`bpf_t` instance:int bpf_user_get_magic(bpf_t* bpf); void bpf_user_set_magic(bpf_t* bpf, int value); size_t bpf_user_send_packet(bpf_t* bpf, char* data, size_t len) \ size_t bpf_user_read_packet(bpf_t* bpf, char* buffer, size_t len)
Note that when passing pointers these must be checked using either
bpf_store_allowed()
orbpf_load_allowed()
.See
appcalls.cpp
for the implementations.
References
SoC support
esp32
esp32c2
esp32c3
esp32s2
esp32s3
esp8266
host
rp2040