1 /* $OpenBSD: test_sshbuf_fuzz.c,v 1.1 2014/04/30 05:32:00 djm Exp $ */ 2 /* 3 * Regress test for sshbuf.h buffer API 4 * 5 * Placed in the public domain 6 */ 7 8 #include <sys/types.h> 9 #include <sys/param.h> 10 #include <stdio.h> 11 #include <stdint.h> 12 #include <stdlib.h> 13 #include <string.h> 14 15 #include "test_helper.h" 16 17 #include "ssherr.h" 18 #include "sshbuf.h" 19 20 #define NUM_FUZZ_TESTS (1 << 18) 21 22 void sshbuf_fuzz_tests(void); 23 24 void 25 sshbuf_fuzz_tests(void) 26 { 27 struct sshbuf *p1; 28 u_char *dp; 29 size_t sz, sz2, i; 30 u_int32_t r; 31 int ret; 32 33 /* NB. uses sshbuf internals */ 34 TEST_START("fuzz alloc/dealloc"); 35 p1 = sshbuf_new(); 36 ASSERT_INT_EQ(sshbuf_set_max_size(p1, 16 * 1024), 0); 37 ASSERT_PTR_NE(p1, NULL); 38 ASSERT_PTR_NE(sshbuf_ptr(p1), NULL); 39 ASSERT_MEM_ZERO_NE(sshbuf_ptr(p1), sshbuf_len(p1)); 40 for (i = 0; i < NUM_FUZZ_TESTS; i++) { 41 r = arc4random_uniform(10); 42 if (r == 0) { 43 /* 10% chance: small reserve */ 44 r = arc4random_uniform(10); 45 fuzz_reserve: 46 sz = sshbuf_avail(p1); 47 sz2 = sshbuf_len(p1); 48 ret = sshbuf_reserve(p1, r, &dp); 49 if (ret < 0) { 50 ASSERT_PTR_EQ(dp, NULL); 51 ASSERT_SIZE_T_LT(sz, r); 52 ASSERT_SIZE_T_EQ(sshbuf_avail(p1), sz); 53 ASSERT_SIZE_T_EQ(sshbuf_len(p1), sz2); 54 } else { 55 ASSERT_PTR_NE(dp, NULL); 56 ASSERT_SIZE_T_GE(sz, r); 57 ASSERT_SIZE_T_EQ(sshbuf_avail(p1), sz - r); 58 ASSERT_SIZE_T_EQ(sshbuf_len(p1), sz2 + r); 59 memset(dp, arc4random_uniform(255) + 1, r); 60 } 61 } else if (r < 3) { 62 /* 20% chance: big reserve */ 63 r = arc4random_uniform(8 * 1024); 64 goto fuzz_reserve; 65 } else if (r == 3) { 66 /* 10% chance: small consume */ 67 r = arc4random_uniform(10); 68 fuzz_consume: 69 sz = sshbuf_avail(p1); 70 sz2 = sshbuf_len(p1); 71 /* 50% change consume from end, otherwise start */ 72 ret = ((arc4random() & 1) ? 73 sshbuf_consume : sshbuf_consume_end)(p1, r); 74 if (ret < 0) { 75 ASSERT_SIZE_T_LT(sz2, r); 76 ASSERT_SIZE_T_EQ(sshbuf_avail(p1), sz); 77 ASSERT_SIZE_T_EQ(sshbuf_len(p1), sz2); 78 } else { 79 ASSERT_SIZE_T_GE(sz2, r); 80 ASSERT_SIZE_T_EQ(sshbuf_avail(p1), sz + r); 81 ASSERT_SIZE_T_EQ(sshbuf_len(p1), sz2 - r); 82 } 83 } else if (r < 8) { 84 /* 40% chance: big consume */ 85 r = arc4random_uniform(2 * 1024); 86 goto fuzz_consume; 87 } else if (r == 8) { 88 /* 10% chance: reset max size */ 89 r = arc4random_uniform(16 * 1024); 90 sz = sshbuf_max_size(p1); 91 if (sshbuf_set_max_size(p1, r) < 0) 92 ASSERT_SIZE_T_EQ(sshbuf_max_size(p1), sz); 93 else 94 ASSERT_SIZE_T_EQ(sshbuf_max_size(p1), r); 95 } else { 96 if (arc4random_uniform(8192) == 0) { 97 /* tiny chance: new buffer */ 98 ASSERT_PTR_NE(sshbuf_ptr(p1), NULL); 99 ASSERT_MEM_ZERO_NE(sshbuf_ptr(p1), sshbuf_len(p1)); 100 sshbuf_free(p1); 101 p1 = sshbuf_new(); 102 ASSERT_PTR_NE(p1, NULL); 103 ASSERT_INT_EQ(sshbuf_set_max_size(p1, 104 16 * 1024), 0); 105 } else { 106 /* Almost 10%: giant reserve */ 107 /* use arc4random_buf for r > 2^32 on 64 bit */ 108 arc4random_buf(&r, sizeof(r)); 109 while (r < SSHBUF_SIZE_MAX / 2) { 110 r <<= 1; 111 r |= arc4random() & 1; 112 } 113 goto fuzz_reserve; 114 } 115 } 116 ASSERT_PTR_NE(sshbuf_ptr(p1), NULL); 117 ASSERT_SIZE_T_LE(sshbuf_max_size(p1), 16 * 1024); 118 } 119 ASSERT_PTR_NE(sshbuf_ptr(p1), NULL); 120 ASSERT_MEM_ZERO_NE(sshbuf_ptr(p1), sshbuf_len(p1)); 121 sshbuf_free(p1); 122 TEST_DONE(); 123 } 124