diff options
Diffstat (limited to 'utils/libtokencap/libtokencap.so.c')
| -rw-r--r-- | utils/libtokencap/libtokencap.so.c | 794 |
1 files changed, 794 insertions, 0 deletions
diff --git a/utils/libtokencap/libtokencap.so.c b/utils/libtokencap/libtokencap.so.c new file mode 100644 index 00000000..3629e804 --- /dev/null +++ b/utils/libtokencap/libtokencap.so.c @@ -0,0 +1,794 @@ +/* + + american fuzzy lop++ - extract tokens passed to strcmp / memcmp + ------------------------------------------------------------- + + Originally written by Michal Zalewski + + Copyright 2016 Google Inc. All rights reserved. + Copyright 2019-2020 AFLplusplus Project. All rights reserved. + + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at: + + http://www.apache.org/licenses/LICENSE-2.0 + + This Linux-only companion library allows you to instrument strcmp(), + memcmp(), and related functions to automatically extract tokens. + See README.tokencap.md for more info. + + */ + +#ifndef _GNU_SOURCE + #define _GNU_SOURCE +#endif +#include <stdio.h> +#include <string.h> +#include <ctype.h> +#include <unistd.h> +#include <fcntl.h> +#include <stdbool.h> + +#include "../types.h" +#include "../config.h" + +#if !defined __linux__ && !defined __APPLE__ && !defined __FreeBSD__ && \ + !defined __OpenBSD__ && !defined __NetBSD__ && !defined __DragonFly__ && \ + !defined(__HAIKU__) && !defined(__sun) + #error "Sorry, this library is unsupported in this platform for now!" +#endif /* !__linux__ && !__APPLE__ && ! __FreeBSD__ && ! __OpenBSD__ && \ + !__NetBSD__*/ + +#if defined __APPLE__ + #include <mach/vm_map.h> + #include <mach/mach_init.h> +#elif defined __FreeBSD__ || defined __OpenBSD__ || defined __NetBSD__ + #include <sys/types.h> + #include <sys/sysctl.h> + #if !defined __NetBSD__ + #include <sys/user.h> + #endif + #include <sys/mman.h> +#elif defined __HAIKU__ + #include <kernel/image.h> +#elif defined __sun + /* For map addresses the old struct is enough */ + #include <sys/procfs.h> + #include <limits.h> +#endif + +#include <dlfcn.h> + +#ifdef RTLD_NEXT +/* The libc functions are a magnitude faster than our replacements. + Use them when RTLD_NEXT is available. */ +int (*__libc_strcmp)(const char *str1, const char *str2); +int (*__libc_strncmp)(const char *str1, const char *str2, size_t len); +int (*__libc_strcasecmp)(const char *str1, const char *str2); +int (*__libc_strncasecmp)(const char *str1, const char *str2, size_t len); +int (*__libc_memcmp)(const void *mem1, const void *mem2, size_t len); +int (*__libc_bcmp)(const void *mem1, const void *mem2, size_t len); +char *(*__libc_strstr)(const char *haystack, const char *needle); +char *(*__libc_strcasestr)(const char *haystack, const char *needle); +void *(*__libc_memmem)(const void *haystack, size_t haystack_len, + const void *needle, size_t needle_len); +#endif + +/* Mapping data and such */ + +#define MAX_MAPPINGS 1024 + +static struct mapping { void *st, *en; } __tokencap_ro[MAX_MAPPINGS]; + +static u32 __tokencap_ro_cnt; +static u8 __tokencap_ro_loaded; +static int __tokencap_out_file = -1; +static pid_t __tokencap_pid = -1; + +/* Identify read-only regions in memory. Only parameters that fall into these + ranges are worth dumping when passed to strcmp() and so on. Read-write + regions are far more likely to contain user input instead. */ + +static void __tokencap_load_mappings(void) { + +#if defined __linux__ + + u8 buf[MAX_LINE]; + FILE *f = fopen("/proc/self/maps", "r"); + + __tokencap_ro_loaded = 1; + + if (!f) return; + + while (fgets(buf, MAX_LINE, f)) { + + u8 rf, wf; + void *st, *en; + + if (sscanf(buf, "%p-%p %c%c", &st, &en, &rf, &wf) != 4) continue; + if (wf == 'w' || rf != 'r') continue; + + __tokencap_ro[__tokencap_ro_cnt].st = (void *)st; + __tokencap_ro[__tokencap_ro_cnt].en = (void *)en; + + if (++__tokencap_ro_cnt == MAX_MAPPINGS) break; + + } + + fclose(f); + +#elif defined __APPLE__ + + struct vm_region_submap_info_64 region; + mach_msg_type_number_t cnt = VM_REGION_SUBMAP_INFO_COUNT_64; + vm_address_t base = 0; + vm_size_t size = 0; + natural_t depth = 0; + + __tokencap_ro_loaded = 1; + + while (1) { + + if (vm_region_recurse_64(mach_task_self(), &base, &size, &depth, + (vm_region_info_64_t)®ion, + &cnt) != KERN_SUCCESS) + break; + + if (region.is_submap) { + + depth++; + + } else { + + /* We only care of main map addresses and the read only kinds */ + if ((region.protection & VM_PROT_READ) && + !(region.protection & VM_PROT_WRITE)) { + + __tokencap_ro[__tokencap_ro_cnt].st = (void *)base; + __tokencap_ro[__tokencap_ro_cnt].en = (void *)(base + size); + + if (++__tokencap_ro_cnt == MAX_MAPPINGS) break; + + } + + base += size; + size = 0; + + } + + } + +#elif defined __FreeBSD__ || defined __OpenBSD__ || defined __NetBSD__ + + #if defined __FreeBSD__ + int mib[] = {CTL_KERN, KERN_PROC, KERN_PROC_VMMAP, __tokencap_pid}; + #elif defined __OpenBSD__ + int mib[] = {CTL_KERN, KERN_PROC_VMMAP, __tokencap_pid}; + #elif defined __NetBSD__ + int mib[] = {CTL_VM, VM_PROC, VM_PROC_MAP, __tokencap_pid, + sizeof(struct kinfo_vmentry)}; + #endif + char * buf, *low, *high; + size_t miblen = sizeof(mib) / sizeof(mib[0]); + size_t len; + + if (sysctl(mib, miblen, NULL, &len, NULL, 0) == -1) return; + + #if defined __FreeBSD__ || defined __NetBSD__ + len = len * 4 / 3; + #elif defined __OpenBSD__ + len -= len % sizeof(struct kinfo_vmentry); + #endif + + buf = mmap(NULL, len, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANON, -1, 0); + if (buf == MAP_FAILED) return; + + if (sysctl(mib, miblen, buf, &len, NULL, 0) == -1) { + + munmap(buf, len); + return; + + } + + low = buf; + high = low + len; + + __tokencap_ro_loaded = 1; + + while (low < high) { + + struct kinfo_vmentry *region = (struct kinfo_vmentry *)low; + + #if defined __FreeBSD__ || defined __NetBSD__ + + #if defined __FreeBSD__ + size_t size = region->kve_structsize; + + if (size == 0) break; + #elif defined __NetBSD__ + size_t size = sizeof(*region); + #endif + + /* We go through the whole mapping of the process and track read-only + * addresses */ + if ((region->kve_protection & KVME_PROT_READ) && + !(region->kve_protection & KVME_PROT_WRITE)) { + + #elif defined __OpenBSD__ + + size_t size = sizeof(*region); + + /* We go through the whole mapping of the process and track read-only + * addresses */ + if ((region->kve_protection & KVE_PROT_READ) && + !(region->kve_protection & KVE_PROT_WRITE)) { + + #endif + __tokencap_ro[__tokencap_ro_cnt].st = (void *)region->kve_start; + __tokencap_ro[__tokencap_ro_cnt].en = (void *)region->kve_end; + + if (++__tokencap_ro_cnt == MAX_MAPPINGS) break; + + } + + low += size; + + } + + munmap(buf, len); +#elif defined __HAIKU__ + image_info ii; + int32_t group = 0; + + __tokencap_ro_loaded = 1; + + while (get_next_image_info(0, &group, &ii) == B_OK) { + + __tokencap_ro[__tokencap_ro_cnt].st = ii.text; + __tokencap_ro[__tokencap_ro_cnt].en = ((char *)ii.text) + ii.text_size; + + if (++__tokencap_ro_cnt == MAX_MAPPINGS) break; + + } + +#elif defined __sun + prmap_t *c, *map; + char path[PATH_MAX]; + ssize_t r; + size_t hint; + int fd; + + snprintf(path, sizeof(path), "/proc/%ld/map", getpid()); + fd = open(path, O_RDONLY); + hint = (1 << 20); + map = malloc(hint); + + __tokencap_ro_loaded = 1; + + for (; (r = pread(fd, map, hint, 0)) == hint;) { + + hint <<= 1; + map = realloc(map, hint); + + } + + for (c = map; r > 0; c++, r -= sizeof(prmap_t)) { + + __tokencap_ro[__tokencap_ro_cnt].st = (void *)c->pr_vaddr; + __tokencap_ro[__tokencap_ro_cnt].en = (void *)(c->pr_vaddr + c->pr_size); + + if (++__tokencap_ro_cnt == MAX_MAPPINGS) break; + + } + + free(map); + close(fd); +#endif + +} + +/* Check an address against the list of read-only mappings. */ + +static u8 __tokencap_is_ro(const void *ptr) { + + u32 i; + + if (!__tokencap_ro_loaded) __tokencap_load_mappings(); + + for (i = 0; i < __tokencap_ro_cnt; i++) + if (ptr >= __tokencap_ro[i].st && ptr <= __tokencap_ro[i].en) return 1; + + return 0; + +} + +/* Dump an interesting token to output file, quoting and escaping it + properly. */ + +static void __tokencap_dump(const u8 *ptr, size_t len, u8 is_text) { + + u8 buf[MAX_AUTO_EXTRA * 4 + 1]; + u32 i; + u32 pos = 0; + + if (len < MIN_AUTO_EXTRA || len > MAX_AUTO_EXTRA || __tokencap_out_file == -1) + return; + + for (i = 0; i < len; i++) { + + if (is_text && !ptr[i]) break; + + switch (ptr[i]) { + + case 0 ... 31: + case 127 ... 255: + case '\"': + case '\\': + + sprintf(buf + pos, "\\x%02x", ptr[i]); + pos += 4; + break; + + default: + buf[pos++] = ptr[i]; + + } + + } + + buf[pos] = 0; + + int wrt_ok = (1 == write(__tokencap_out_file, "\"", 1)); + wrt_ok &= (pos == write(__tokencap_out_file, buf, pos)); + wrt_ok &= (2 == write(__tokencap_out_file, "\"\n", 2)); + +} + +/* Replacements for strcmp(), memcmp(), and so on. Note that these will be used + only if the target is compiled with -fno-builtins and linked dynamically. */ + +#undef strcmp + +int strcmp(const char *str1, const char *str2) { + + if (__tokencap_is_ro(str1)) __tokencap_dump(str1, strlen(str1), 1); + if (__tokencap_is_ro(str2)) __tokencap_dump(str2, strlen(str2), 1); + +#ifdef RTLD_NEXT + if (__libc_strcmp) return __libc_strcmp(str1, str2); +#endif + + while (1) { + + const unsigned char c1 = *str1, c2 = *str2; + + if (c1 != c2) return (c1 > c2) ? 1 : -1; + if (!c1) return 0; + str1++; + str2++; + + } + +} + +#undef strncmp + +int strncmp(const char *str1, const char *str2, size_t len) { + + if (__tokencap_is_ro(str1)) __tokencap_dump(str1, len, 1); + if (__tokencap_is_ro(str2)) __tokencap_dump(str2, len, 1); + +#ifdef RTLD_NEXT + if (__libc_strncmp) return __libc_strncmp(str1, str2, len); +#endif + + while (len--) { + + unsigned char c1 = *str1, c2 = *str2; + + if (c1 != c2) return (c1 > c2) ? 1 : -1; + if (!c1) return 0; + str1++; + str2++; + + } + + return 0; + +} + +#undef strcasecmp + +int strcasecmp(const char *str1, const char *str2) { + + if (__tokencap_is_ro(str1)) __tokencap_dump(str1, strlen(str1), 1); + if (__tokencap_is_ro(str2)) __tokencap_dump(str2, strlen(str2), 1); + +#ifdef RTLD_NEXT + if (__libc_strcasecmp) return __libc_strcasecmp(str1, str2); +#endif + + while (1) { + + const unsigned char c1 = tolower((int)*str1), c2 = tolower((int)*str2); + + if (c1 != c2) return (c1 > c2) ? 1 : -1; + if (!c1) return 0; + str1++; + str2++; + + } + +} + +#undef strncasecmp + +int strncasecmp(const char *str1, const char *str2, size_t len) { + + if (__tokencap_is_ro(str1)) __tokencap_dump(str1, len, 1); + if (__tokencap_is_ro(str2)) __tokencap_dump(str2, len, 1); + +#ifdef RTLD_NEXT + if (__libc_strncasecmp) return __libc_strncasecmp(str1, str2, len); +#endif + + while (len--) { + + const unsigned char c1 = tolower((int)*str1), c2 = tolower((int)*str2); + + if (c1 != c2) return (c1 > c2) ? 1 : -1; + if (!c1) return 0; + str1++; + str2++; + + } + + return 0; + +} + +#undef memcmp + +int memcmp(const void *mem1, const void *mem2, size_t len) { + + if (__tokencap_is_ro(mem1)) __tokencap_dump(mem1, len, 0); + if (__tokencap_is_ro(mem2)) __tokencap_dump(mem2, len, 0); + +#ifdef RTLD_NEXT + if (__libc_memcmp) return __libc_memcmp(mem1, mem2, len); +#endif + + const char *strmem1 = (const char *)mem1; + const char *strmem2 = (const char *)mem2; + + while (len--) { + + const unsigned char c1 = *strmem1, c2 = *strmem2; + if (c1 != c2) return (c1 > c2) ? 1 : -1; + strmem1++; + strmem2++; + + } + + return 0; + +} + +#undef bcmp + +int bcmp(const void *mem1, const void *mem2, size_t len) { + + if (__tokencap_is_ro(mem1)) __tokencap_dump(mem1, len, 0); + if (__tokencap_is_ro(mem2)) __tokencap_dump(mem2, len, 0); + +#ifdef RTLD_NEXT + if (__libc_bcmp) return __libc_bcmp(mem1, mem2, len); +#endif + + const char *strmem1 = (const char *)mem1; + const char *strmem2 = (const char *)mem2; + + while (len--) { + + int diff = *strmem1 ^ *strmem2; + if (diff != 0) return 1; + strmem1++; + strmem2++; + + } + + return 0; + +} + +#undef strstr + +char *strstr(const char *haystack, const char *needle) { + + if (__tokencap_is_ro(haystack)) + __tokencap_dump(haystack, strlen(haystack), 1); + + if (__tokencap_is_ro(needle)) __tokencap_dump(needle, strlen(needle), 1); + +#ifdef RTLD_NEXT + if (__libc_strstr) return __libc_strstr(haystack, needle); +#endif + + do { + + const char *n = needle; + const char *h = haystack; + + while (*n && *h && *n == *h) + n++, h++; + + if (!*n) return (char *)haystack; + + } while (*(haystack++)); + + return 0; + +} + +#undef strcasestr + +char *strcasestr(const char *haystack, const char *needle) { + + if (__tokencap_is_ro(haystack)) + __tokencap_dump(haystack, strlen(haystack), 1); + + if (__tokencap_is_ro(needle)) __tokencap_dump(needle, strlen(needle), 1); + +#ifdef RTLD_NEXT + if (__libc_strcasestr) return __libc_strcasestr(haystack, needle); +#endif + + do { + + const char *n = needle; + const char *h = haystack; + + while (*n && *h && tolower((int)*n) == tolower((int)*h)) + n++, h++; + + if (!*n) return (char *)haystack; + + } while (*(haystack++)); + + return 0; + +} + +#undef memmem + +void *memmem(const void *haystack, size_t haystack_len, const void *needle, + size_t needle_len) { + + if (__tokencap_is_ro(haystack)) __tokencap_dump(haystack, haystack_len, 1); + + if (__tokencap_is_ro(needle)) __tokencap_dump(needle, needle_len, 1); + +#ifdef RTLD_NEXT + if (__libc_memmem) + return __libc_memmem(haystack, haystack_len, needle, needle_len); +#endif + + const char *n = (const char *)needle; + const char *h = (const char *)haystack; + if (haystack_len < needle_len) return 0; + if (needle_len == 0) return (void *)haystack; + if (needle_len == 1) return memchr(haystack, *n, haystack_len); + + const char *end = h + (haystack_len - needle_len); + + do { + + if (*h == *n) { + + if (memcmp(h, n, needle_len) == 0) return (void *)h; + + } + + } while (h++ <= end); + + return 0; + +} + +/* Common libraries wrappers (from honggfuzz) */ + +/* + * Apache's httpd wrappers + */ +int ap_cstr_casecmp(const char *s1, const char *s2) { + + return strcasecmp(s1, s2); + +} + +int ap_cstr_casecmpn(const char *s1, const char *s2, size_t n) { + + return strncasecmp(s1, s2, n); + +} + +const char *ap_strcasestr(const char *s1, const char *s2) { + + return strcasestr(s1, s2); + +} + +int apr_cstr_casecmp(const char *s1, const char *s2) { + + return strcasecmp(s1, s2); + +} + +int apr_cstr_casecmpn(const char *s1, const char *s2, size_t n) { + + return strncasecmp(s1, s2, n); + +} + +/* + * *SSL wrappers + */ +int CRYPTO_memcmp(const void *m1, const void *m2, size_t len) { + + return memcmp(m1, m2, len); + +} + +int OPENSSL_memcmp(const void *m1, const void *m2, size_t len) { + + return memcmp(m1, m2, len); + +} + +int OPENSSL_strcasecmp(const char *s1, const char *s2) { + + return strcasecmp(s1, s2); + +} + +int OPENSSL_strncasecmp(const char *s1, const char *s2, size_t len) { + + return strncasecmp(s1, s2, len); + +} + +int32_t memcmpct(const void *s1, const void *s2, size_t len) { + + return memcmp(s1, s2, len); + +} + +/* + * libXML wrappers + */ +int xmlStrncmp(const char *s1, const char *s2, int len) { + + if (len <= 0) { return 0; } + if (s1 == s2) { return 0; } + if (s1 == NULL) { return -1; } + if (s2 == NULL) { return 1; } + return strncmp(s1, s2, (size_t)len); + +} + +int xmlStrcmp(const char *s1, const char *s2) { + + if (s1 == s2) { return 0; } + if (s1 == NULL) { return -1; } + if (s2 == NULL) { return 1; } + return strcmp(s1, s2); + +} + +int xmlStrEqual(const char *s1, const char *s2) { + + if (s1 == s2) { return 1; } + if (s1 == NULL) { return 0; } + if (s2 == NULL) { return 0; } + if (strcmp(s1, s2) == 0) { return 1; } + return 0; + +} + +int xmlStrcasecmp(const char *s1, const char *s2) { + + if (s1 == s2) { return 0; } + if (s1 == NULL) { return -1; } + if (s2 == NULL) { return 1; } + return strcasecmp(s1, s2); + +} + +int xmlStrncasecmp(const char *s1, const char *s2, int len) { + + if (len <= 0) { return 0; } + if (s1 == s2) { return 0; } + if (s1 == NULL) { return -1; } + if (s2 == NULL) { return 1; } + return strncasecmp(s1, s2, (size_t)len); + +} + +const char *xmlStrstr(const char *haystack, const char *needle) { + + if (haystack == NULL) { return NULL; } + if (needle == NULL) { return NULL; } + return strstr(haystack, needle); + +} + +const char *xmlStrcasestr(const char *haystack, const char *needle) { + + if (haystack == NULL) { return NULL; } + if (needle == NULL) { return NULL; } + return strcasestr(haystack, needle); + +} + +/* + * Samba wrappers + */ +int memcmp_const_time(const void *s1, const void *s2, size_t n) { + + return memcmp(s1, s2, n); + +} + +bool strcsequal(const void *s1, const void *s2) { + + if (s1 == s2) { return true; } + if (!s1 || !s2) { return false; } + return (strcmp(s1, s2) == 0); + +} + +/* bcmp/memcmp BSD flavors, similar to CRYPTO_memcmp */ + +int timingsafe_bcmp(const void *mem1, const void *mem2, size_t len) { + + return bcmp(mem1, mem2, len); + +} + +int timingsafe_memcmp(const void *mem1, const void *mem2, size_t len) { + + return memcmp(mem1, mem2, len); + +} + +/* Init code to open the output file (or default to stderr). */ + +__attribute__((constructor)) void __tokencap_init(void) { + + u8 *fn = getenv("AFL_TOKEN_FILE"); + if (fn) __tokencap_out_file = open(fn, O_RDWR | O_CREAT | O_APPEND, 0655); + if (__tokencap_out_file == -1) __tokencap_out_file = STDERR_FILENO; + __tokencap_pid = getpid(); + +#ifdef RTLD_NEXT + __libc_strcmp = dlsym(RTLD_NEXT, "strcmp"); + __libc_strncmp = dlsym(RTLD_NEXT, "strncmp"); + __libc_strcasecmp = dlsym(RTLD_NEXT, "strcasecmp"); + __libc_strncasecmp = dlsym(RTLD_NEXT, "strncasecmp"); + __libc_memcmp = dlsym(RTLD_NEXT, "memcmp"); + __libc_bcmp = dlsym(RTLD_NEXT, "bcmp"); + __libc_strstr = dlsym(RTLD_NEXT, "strstr"); + __libc_strcasestr = dlsym(RTLD_NEXT, "strcasestr"); + __libc_memmem = dlsym(RTLD_NEXT, "memmem"); +#endif + +} + +/* closing as best as we can the tokens file */ +__attribute__((destructor)) void __tokencap_shutdown(void) { + + if (__tokencap_out_file != STDERR_FILENO) close(__tokencap_out_file); + +} + |