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1/* SPDX-License-Identifier: GPL-2.0 */2#ifndef __BPF_RAND__3#define __BPF_RAND__4 5#include <stdint.h>6#include <stdlib.h>7#include <time.h>8 9static inline uint64_t bpf_rand_mask(uint64_t mask)10{11 return (((uint64_t)(uint32_t)rand()) |12 ((uint64_t)(uint32_t)rand() << 32)) & mask;13}14 15#define bpf_rand_ux(x, m) \16static inline uint64_t bpf_rand_u##x(int shift) \17{ \18 return bpf_rand_mask((m)) << shift; \19}20 21bpf_rand_ux( 8, 0xffULL)22bpf_rand_ux(16, 0xffffULL)23bpf_rand_ux(24, 0xffffffULL)24bpf_rand_ux(32, 0xffffffffULL)25bpf_rand_ux(40, 0xffffffffffULL)26bpf_rand_ux(48, 0xffffffffffffULL)27bpf_rand_ux(56, 0xffffffffffffffULL)28bpf_rand_ux(64, 0xffffffffffffffffULL)29 30static inline void bpf_semi_rand_init(void)31{32 srand(time(NULL));33}34 35static inline uint64_t bpf_semi_rand_get(void)36{37 switch (rand() % 39) {38 case 0: return 0x000000ff00000000ULL | bpf_rand_u8(0);39 case 1: return 0xffffffff00000000ULL | bpf_rand_u16(0);40 case 2: return 0x00000000ffff0000ULL | bpf_rand_u16(0);41 case 3: return 0x8000000000000000ULL | bpf_rand_u32(0);42 case 4: return 0x00000000f0000000ULL | bpf_rand_u32(0);43 case 5: return 0x0000000100000000ULL | bpf_rand_u24(0);44 case 6: return 0x800ff00000000000ULL | bpf_rand_u32(0);45 case 7: return 0x7fffffff00000000ULL | bpf_rand_u32(0);46 case 8: return 0xffffffffffffff00ULL ^ bpf_rand_u32(24);47 case 9: return 0xffffffffffffff00ULL | bpf_rand_u8(0);48 case 10: return 0x0000000010000000ULL | bpf_rand_u32(0);49 case 11: return 0xf000000000000000ULL | bpf_rand_u8(0);50 case 12: return 0x0000f00000000000ULL | bpf_rand_u8(8);51 case 13: return 0x000000000f000000ULL | bpf_rand_u8(16);52 case 14: return 0x0000000000000f00ULL | bpf_rand_u8(32);53 case 15: return 0x00fff00000000f00ULL | bpf_rand_u8(48);54 case 16: return 0x00007fffffffffffULL ^ bpf_rand_u32(1);55 case 17: return 0xffff800000000000ULL | bpf_rand_u8(4);56 case 18: return 0xffff800000000000ULL | bpf_rand_u8(20);57 case 19: return (0xffffffc000000000ULL + 0x80000ULL) | bpf_rand_u32(0);58 case 20: return (0xffffffc000000000ULL - 0x04000000ULL) | bpf_rand_u32(0);59 case 21: return 0x0000000000000000ULL | bpf_rand_u8(55) | bpf_rand_u32(20);60 case 22: return 0xffffffffffffffffULL ^ bpf_rand_u8(3) ^ bpf_rand_u32(40);61 case 23: return 0x0000000000000000ULL | bpf_rand_u8(bpf_rand_u8(0) % 64);62 case 24: return 0x0000000000000000ULL | bpf_rand_u16(bpf_rand_u8(0) % 64);63 case 25: return 0xffffffffffffffffULL ^ bpf_rand_u8(bpf_rand_u8(0) % 64);64 case 26: return 0xffffffffffffffffULL ^ bpf_rand_u40(bpf_rand_u8(0) % 64);65 case 27: return 0x0000800000000000ULL;66 case 28: return 0x8000000000000000ULL;67 case 29: return 0x0000000000000000ULL;68 case 30: return 0xffffffffffffffffULL;69 case 31: return bpf_rand_u16(bpf_rand_u8(0) % 64);70 case 32: return bpf_rand_u24(bpf_rand_u8(0) % 64);71 case 33: return bpf_rand_u32(bpf_rand_u8(0) % 64);72 case 34: return bpf_rand_u40(bpf_rand_u8(0) % 64);73 case 35: return bpf_rand_u48(bpf_rand_u8(0) % 64);74 case 36: return bpf_rand_u56(bpf_rand_u8(0) % 64);75 case 37: return bpf_rand_u64(bpf_rand_u8(0) % 64);76 default: return bpf_rand_u64(0);77 }78}79 80#endif /* __BPF_RAND__ */81