1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */ 2*4882a593Smuzhiyun #ifndef __BPF_RAND__ 3*4882a593Smuzhiyun #define __BPF_RAND__ 4*4882a593Smuzhiyun 5*4882a593Smuzhiyun #include <stdint.h> 6*4882a593Smuzhiyun #include <stdlib.h> 7*4882a593Smuzhiyun #include <time.h> 8*4882a593Smuzhiyun bpf_rand_mask(uint64_t mask)9*4882a593Smuzhiyunstatic inline uint64_t bpf_rand_mask(uint64_t mask) 10*4882a593Smuzhiyun { 11*4882a593Smuzhiyun return (((uint64_t)(uint32_t)rand()) | 12*4882a593Smuzhiyun ((uint64_t)(uint32_t)rand() << 32)) & mask; 13*4882a593Smuzhiyun } 14*4882a593Smuzhiyun 15*4882a593Smuzhiyun #define bpf_rand_ux(x, m) \ 16*4882a593Smuzhiyun static inline uint64_t bpf_rand_u##x(int shift) \ 17*4882a593Smuzhiyun { \ 18*4882a593Smuzhiyun return bpf_rand_mask((m)) << shift; \ 19*4882a593Smuzhiyun } 20*4882a593Smuzhiyun 21*4882a593Smuzhiyun bpf_rand_ux( 8, 0xffULL) 22*4882a593Smuzhiyun bpf_rand_ux(16, 0xffffULL) 23*4882a593Smuzhiyun bpf_rand_ux(24, 0xffffffULL) 24*4882a593Smuzhiyun bpf_rand_ux(32, 0xffffffffULL) 25*4882a593Smuzhiyun bpf_rand_ux(40, 0xffffffffffULL) 26*4882a593Smuzhiyun bpf_rand_ux(48, 0xffffffffffffULL) 27*4882a593Smuzhiyun bpf_rand_ux(56, 0xffffffffffffffULL) 28*4882a593Smuzhiyun bpf_rand_ux(64, 0xffffffffffffffffULL) 29*4882a593Smuzhiyun bpf_semi_rand_init(void)30*4882a593Smuzhiyunstatic inline void bpf_semi_rand_init(void) 31*4882a593Smuzhiyun { 32*4882a593Smuzhiyun srand(time(NULL)); 33*4882a593Smuzhiyun } 34*4882a593Smuzhiyun bpf_semi_rand_get(void)35*4882a593Smuzhiyunstatic inline uint64_t bpf_semi_rand_get(void) 36*4882a593Smuzhiyun { 37*4882a593Smuzhiyun switch (rand() % 39) { 38*4882a593Smuzhiyun case 0: return 0x000000ff00000000ULL | bpf_rand_u8(0); 39*4882a593Smuzhiyun case 1: return 0xffffffff00000000ULL | bpf_rand_u16(0); 40*4882a593Smuzhiyun case 2: return 0x00000000ffff0000ULL | bpf_rand_u16(0); 41*4882a593Smuzhiyun case 3: return 0x8000000000000000ULL | bpf_rand_u32(0); 42*4882a593Smuzhiyun case 4: return 0x00000000f0000000ULL | bpf_rand_u32(0); 43*4882a593Smuzhiyun case 5: return 0x0000000100000000ULL | bpf_rand_u24(0); 44*4882a593Smuzhiyun case 6: return 0x800ff00000000000ULL | bpf_rand_u32(0); 45*4882a593Smuzhiyun case 7: return 0x7fffffff00000000ULL | bpf_rand_u32(0); 46*4882a593Smuzhiyun case 8: return 0xffffffffffffff00ULL ^ bpf_rand_u32(24); 47*4882a593Smuzhiyun case 9: return 0xffffffffffffff00ULL | bpf_rand_u8(0); 48*4882a593Smuzhiyun case 10: return 0x0000000010000000ULL | bpf_rand_u32(0); 49*4882a593Smuzhiyun case 11: return 0xf000000000000000ULL | bpf_rand_u8(0); 50*4882a593Smuzhiyun case 12: return 0x0000f00000000000ULL | bpf_rand_u8(8); 51*4882a593Smuzhiyun case 13: return 0x000000000f000000ULL | bpf_rand_u8(16); 52*4882a593Smuzhiyun case 14: return 0x0000000000000f00ULL | bpf_rand_u8(32); 53*4882a593Smuzhiyun case 15: return 0x00fff00000000f00ULL | bpf_rand_u8(48); 54*4882a593Smuzhiyun case 16: return 0x00007fffffffffffULL ^ bpf_rand_u32(1); 55*4882a593Smuzhiyun case 17: return 0xffff800000000000ULL | bpf_rand_u8(4); 56*4882a593Smuzhiyun case 18: return 0xffff800000000000ULL | bpf_rand_u8(20); 57*4882a593Smuzhiyun case 19: return (0xffffffc000000000ULL + 0x80000ULL) | bpf_rand_u32(0); 58*4882a593Smuzhiyun case 20: return (0xffffffc000000000ULL - 0x04000000ULL) | bpf_rand_u32(0); 59*4882a593Smuzhiyun case 21: return 0x0000000000000000ULL | bpf_rand_u8(55) | bpf_rand_u32(20); 60*4882a593Smuzhiyun case 22: return 0xffffffffffffffffULL ^ bpf_rand_u8(3) ^ bpf_rand_u32(40); 61*4882a593Smuzhiyun case 23: return 0x0000000000000000ULL | bpf_rand_u8(bpf_rand_u8(0) % 64); 62*4882a593Smuzhiyun case 24: return 0x0000000000000000ULL | bpf_rand_u16(bpf_rand_u8(0) % 64); 63*4882a593Smuzhiyun case 25: return 0xffffffffffffffffULL ^ bpf_rand_u8(bpf_rand_u8(0) % 64); 64*4882a593Smuzhiyun case 26: return 0xffffffffffffffffULL ^ bpf_rand_u40(bpf_rand_u8(0) % 64); 65*4882a593Smuzhiyun case 27: return 0x0000800000000000ULL; 66*4882a593Smuzhiyun case 28: return 0x8000000000000000ULL; 67*4882a593Smuzhiyun case 29: return 0x0000000000000000ULL; 68*4882a593Smuzhiyun case 30: return 0xffffffffffffffffULL; 69*4882a593Smuzhiyun case 31: return bpf_rand_u16(bpf_rand_u8(0) % 64); 70*4882a593Smuzhiyun case 32: return bpf_rand_u24(bpf_rand_u8(0) % 64); 71*4882a593Smuzhiyun case 33: return bpf_rand_u32(bpf_rand_u8(0) % 64); 72*4882a593Smuzhiyun case 34: return bpf_rand_u40(bpf_rand_u8(0) % 64); 73*4882a593Smuzhiyun case 35: return bpf_rand_u48(bpf_rand_u8(0) % 64); 74*4882a593Smuzhiyun case 36: return bpf_rand_u56(bpf_rand_u8(0) % 64); 75*4882a593Smuzhiyun case 37: return bpf_rand_u64(bpf_rand_u8(0) % 64); 76*4882a593Smuzhiyun default: return bpf_rand_u64(0); 77*4882a593Smuzhiyun } 78*4882a593Smuzhiyun } 79*4882a593Smuzhiyun 80*4882a593Smuzhiyun #endif /* __BPF_RAND__ */ 81