X-Git-Url: https://git.openssl.org/gitweb/?p=openssl.git;a=blobdiff_plain;f=crypto%2Fcryptlib.c;h=897b5b5bc22a551e6ad21d82a3b21b39a885e9ec;hp=bb54e6485ad0efa18dbcaac1f0dc05120ea54489;hb=c3586512184b4ca6c682c479323ac282ab30298e;hpb=f00fdcd14dd82410fccf5a8b41e7ea38a90e7e79 diff --git a/crypto/cryptlib.c b/crypto/cryptlib.c index bb54e6485a..897b5b5bc2 100644 --- a/crypto/cryptlib.c +++ b/crypto/cryptlib.c @@ -121,547 +121,11 @@ static double SSLeay_MSVC5_hack=0.0; /* and for VC1.5 */ #endif -DECLARE_STACK_OF(CRYPTO_dynlock) - -/* real #defines in crypto.h, keep these upto date */ -static const char* const lock_names[CRYPTO_NUM_LOCKS] = - { - "<>", - "err", - "ex_data", - "x509", - "x509_info", - "x509_pkey", - "x509_crl", - "x509_req", - "dsa", - "rsa", - "evp_pkey", - "x509_store", - "ssl_ctx", - "ssl_cert", - "ssl_session", - "ssl_sess_cert", - "ssl", - "ssl_method", - "rand", - "rand2", - "debug_malloc", - "BIO", - "gethostbyname", - "getservbyname", - "readdir", - "RSA_blinding", - "dh", - "debug_malloc2", - "dso", - "dynlock", - "engine", - "ui", - "ecdsa", - "ec", - "ecdh", - "bn", - "ec_pre_comp", - "store", - "comp", - "fips", - "fips2", -#if CRYPTO_NUM_LOCKS != 41 -# error "Inconsistency between crypto.h and cryptlib.c" -#endif - }; - -/* This is for applications to allocate new type names in the non-dynamic - array of lock names. These are numbered with positive numbers. */ -static STACK_OF(STRING) *app_locks=NULL; - -/* For applications that want a more dynamic way of handling threads, the - following stack is used. These are externally numbered with negative - numbers. */ -static STACK_OF(CRYPTO_dynlock) *dyn_locks=NULL; - - -static void (MS_FAR *locking_callback)(int mode,int type, - const char *file,int line)=0; -static int (MS_FAR *add_lock_callback)(int *pointer,int amount, - int type,const char *file,int line)=0; -#ifndef OPENSSL_NO_DEPRECATED -static unsigned long (MS_FAR *id_callback)(void)=0; -#endif -static void (MS_FAR *threadid_callback)(CRYPTO_THREADID *)=0; -static struct CRYPTO_dynlock_value *(MS_FAR *dynlock_create_callback) - (const char *file,int line)=0; -static void (MS_FAR *dynlock_lock_callback)(int mode, - struct CRYPTO_dynlock_value *l, const char *file,int line)=0; -static void (MS_FAR *dynlock_destroy_callback)(struct CRYPTO_dynlock_value *l, - const char *file,int line)=0; - -int CRYPTO_get_new_lockid(char *name) - { - char *str; - int i; - -#if defined(OPENSSL_SYS_WIN32) || defined(OPENSSL_SYS_WIN16) - /* A hack to make Visual C++ 5.0 work correctly when linking as - * a DLL using /MT. Without this, the application cannot use - * any floating point printf's. - * It also seems to be needed for Visual C 1.5 (win16) */ - SSLeay_MSVC5_hack=(double)name[0]*(double)name[1]; -#endif - - if ((app_locks == NULL) && ((app_locks=sk_STRING_new_null()) == NULL)) - { - CRYPTOerr(CRYPTO_F_CRYPTO_GET_NEW_LOCKID,ERR_R_MALLOC_FAILURE); - return(0); - } - if ((str=BUF_strdup(name)) == NULL) - { - CRYPTOerr(CRYPTO_F_CRYPTO_GET_NEW_LOCKID,ERR_R_MALLOC_FAILURE); - return(0); - } - i=sk_STRING_push(app_locks,str); - if (!i) - OPENSSL_free(str); - else - i+=CRYPTO_NUM_LOCKS; /* gap of one :-) */ - return(i); - } - -int CRYPTO_num_locks(void) - { - return CRYPTO_NUM_LOCKS; - } - -int CRYPTO_get_new_dynlockid(void) - { - int i = 0; - CRYPTO_dynlock *pointer = NULL; - - if (dynlock_create_callback == NULL) - { - CRYPTOerr(CRYPTO_F_CRYPTO_GET_NEW_DYNLOCKID,CRYPTO_R_NO_DYNLOCK_CREATE_CALLBACK); - return(0); - } - CRYPTO_w_lock(CRYPTO_LOCK_DYNLOCK); - if ((dyn_locks == NULL) - && ((dyn_locks=sk_CRYPTO_dynlock_new_null()) == NULL)) - { - CRYPTO_w_unlock(CRYPTO_LOCK_DYNLOCK); - CRYPTOerr(CRYPTO_F_CRYPTO_GET_NEW_DYNLOCKID,ERR_R_MALLOC_FAILURE); - return(0); - } - CRYPTO_w_unlock(CRYPTO_LOCK_DYNLOCK); - - pointer = (CRYPTO_dynlock *)OPENSSL_malloc(sizeof(CRYPTO_dynlock)); - if (pointer == NULL) - { - CRYPTOerr(CRYPTO_F_CRYPTO_GET_NEW_DYNLOCKID,ERR_R_MALLOC_FAILURE); - return(0); - } - pointer->references = 1; - pointer->data = dynlock_create_callback(__FILE__,__LINE__); - if (pointer->data == NULL) - { - OPENSSL_free(pointer); - CRYPTOerr(CRYPTO_F_CRYPTO_GET_NEW_DYNLOCKID,ERR_R_MALLOC_FAILURE); - return(0); - } - - CRYPTO_w_lock(CRYPTO_LOCK_DYNLOCK); - /* First, try to find an existing empty slot */ - i=sk_CRYPTO_dynlock_find(dyn_locks,NULL); - /* If there was none, push, thereby creating a new one */ - if (i == -1) - /* Since sk_push() returns the number of items on the - stack, not the location of the pushed item, we need - to transform the returned number into a position, - by decreasing it. */ - i=sk_CRYPTO_dynlock_push(dyn_locks,pointer) - 1; - else - /* If we found a place with a NULL pointer, put our pointer - in it. */ - (void)sk_CRYPTO_dynlock_set(dyn_locks,i,pointer); - CRYPTO_w_unlock(CRYPTO_LOCK_DYNLOCK); - - if (i == -1) - { - dynlock_destroy_callback(pointer->data,__FILE__,__LINE__); - OPENSSL_free(pointer); - } - else - i += 1; /* to avoid 0 */ - return -i; - } - -void CRYPTO_destroy_dynlockid(int i) - { - CRYPTO_dynlock *pointer = NULL; - if (i) - i = -i-1; - if (dynlock_destroy_callback == NULL) - return; - - CRYPTO_w_lock(CRYPTO_LOCK_DYNLOCK); - - if (dyn_locks == NULL || i >= sk_CRYPTO_dynlock_num(dyn_locks)) - { - CRYPTO_w_unlock(CRYPTO_LOCK_DYNLOCK); - return; - } - pointer = sk_CRYPTO_dynlock_value(dyn_locks, i); - if (pointer != NULL) - { - --pointer->references; -#ifdef REF_CHECK - if (pointer->references < 0) - { - fprintf(stderr,"CRYPTO_destroy_dynlockid, bad reference count\n"); - abort(); - } - else -#endif - if (pointer->references <= 0) - { - (void)sk_CRYPTO_dynlock_set(dyn_locks, i, NULL); - } - else - pointer = NULL; - } - CRYPTO_w_unlock(CRYPTO_LOCK_DYNLOCK); - - if (pointer) - { - dynlock_destroy_callback(pointer->data,__FILE__,__LINE__); - OPENSSL_free(pointer); - } - } - -struct CRYPTO_dynlock_value *CRYPTO_get_dynlock_value(int i) - { - CRYPTO_dynlock *pointer = NULL; - if (i) - i = -i-1; - - CRYPTO_w_lock(CRYPTO_LOCK_DYNLOCK); - - if (dyn_locks != NULL && i < sk_CRYPTO_dynlock_num(dyn_locks)) - pointer = sk_CRYPTO_dynlock_value(dyn_locks, i); - if (pointer) - pointer->references++; - - CRYPTO_w_unlock(CRYPTO_LOCK_DYNLOCK); - - if (pointer) - return pointer->data; - return NULL; - } - -struct CRYPTO_dynlock_value *(*CRYPTO_get_dynlock_create_callback(void)) - (const char *file,int line) - { - return(dynlock_create_callback); - } - -void (*CRYPTO_get_dynlock_lock_callback(void))(int mode, - struct CRYPTO_dynlock_value *l, const char *file,int line) - { - return(dynlock_lock_callback); - } - -void (*CRYPTO_get_dynlock_destroy_callback(void)) - (struct CRYPTO_dynlock_value *l, const char *file,int line) - { - return(dynlock_destroy_callback); - } - -void CRYPTO_set_dynlock_create_callback(struct CRYPTO_dynlock_value *(*func) - (const char *file, int line)) - { - dynlock_create_callback=func; - } - -void CRYPTO_set_dynlock_lock_callback(void (*func)(int mode, - struct CRYPTO_dynlock_value *l, const char *file, int line)) - { - dynlock_lock_callback=func; - } - -void CRYPTO_set_dynlock_destroy_callback(void (*func) - (struct CRYPTO_dynlock_value *l, const char *file, int line)) - { - dynlock_destroy_callback=func; - } - - -void (*CRYPTO_get_locking_callback(void))(int mode,int type,const char *file, - int line) - { - return(locking_callback); - } - -int (*CRYPTO_get_add_lock_callback(void))(int *num,int mount,int type, - const char *file,int line) - { - return(add_lock_callback); - } - -void CRYPTO_set_locking_callback(void (*func)(int mode,int type, - const char *file,int line)) - { - locking_callback=func; - } - -void CRYPTO_set_add_lock_callback(int (*func)(int *num,int mount,int type, - const char *file,int line)) - { - add_lock_callback=func; - } - -/* the memset() here and in set_pointer() seem overkill, but for the sake of - * CRYPTO_THREADID_cmp() this avoids any platform silliness that might cause two - * "equal" THREADID structs to not be memcmp()-identical. */ -void CRYPTO_THREADID_set_numeric(CRYPTO_THREADID *id, unsigned long val) - { - memset(id, 0, sizeof(*id)); - id->val = val; - } - -static const unsigned char hash_coeffs[] = { 3, 5, 7, 11, 13, 17, 19, 23 }; -void CRYPTO_THREADID_set_pointer(CRYPTO_THREADID *id, void *ptr) - { - unsigned char *dest = (void *)&id->val; - unsigned int accum = 0; - unsigned char dnum = sizeof(id->val); - - memset(id, 0, sizeof(*id)); - id->ptr = ptr; - if (sizeof(id->val) >= sizeof(id->ptr)) - { - /* 'ptr' can be embedded in 'val' without loss of uniqueness */ - id->val = (unsigned long)id->ptr; - return; - } - /* hash ptr ==> val. Each byte of 'val' gets the mod-256 total of a - * linear function over the bytes in 'ptr', the co-efficients of which - * are a sequence of low-primes (hash_coeffs is an 8-element cycle) - - * the starting prime for the sequence varies for each byte of 'val' - * (unique polynomials unless pointers are >64-bit). For added spice, - * the totals accumulate rather than restarting from zero, and the index - * of the 'val' byte is added each time (position dependence). If I was - * a black-belt, I'd scan big-endian pointers in reverse to give - * low-order bits more play, but this isn't crypto and I'd prefer nobody - * mistake it as such. Plus I'm lazy. */ - while (dnum--) - { - const unsigned char *src = (void *)&id->ptr; - unsigned char snum = sizeof(id->ptr); - while (snum--) - accum += *(src++) * hash_coeffs[(snum + dnum) & 7]; - accum += dnum; - *(dest++) = accum & 255; - } - } - -int CRYPTO_THREADID_set_callback(void (*func)(CRYPTO_THREADID *)) - { - if (threadid_callback) - return 0; - threadid_callback = func; - return 1; - } - -void (*CRYPTO_THREADID_get_callback(void))(CRYPTO_THREADID *) - { - return threadid_callback; - } - -void CRYPTO_THREADID_current(CRYPTO_THREADID *id) - { - if (threadid_callback) - { - threadid_callback(id); - return; - } -#ifndef OPENSSL_NO_DEPRECATED - /* If the deprecated callback was set, fall back to that */ - if (id_callback) - { - CRYPTO_THREADID_set_numeric(id, id_callback()); - return; - } -#endif - /* Else pick a backup */ -#ifdef OPENSSL_SYS_WIN16 - CRYPTO_THREADID_set_numeric(id, (unsigned long)GetCurrentTask()); -#elif defined(OPENSSL_SYS_WIN32) - CRYPTO_THREADID_set_numeric(id, (unsigned long)GetCurrentThreadId()); -#elif defined(OPENSSL_SYS_BEOS) - CRYPTO_THREADID_set_numeric(id, (unsigned long)find_thread(NULL)); -#else - /* For everything else, default to using the address of 'errno' */ - CRYPTO_THREADID_set_pointer(id, &errno); -#endif - } - -int CRYPTO_THREADID_cmp(const CRYPTO_THREADID *a, const CRYPTO_THREADID *b) - { - return memcmp(a, b, sizeof(*a)); - } - -void CRYPTO_THREADID_cpy(CRYPTO_THREADID *dest, const CRYPTO_THREADID *src) - { - memcpy(dest, src, sizeof(*src)); - } - -unsigned long CRYPTO_THREADID_hash(const CRYPTO_THREADID *id) - { - return id->val; - } - -#ifndef OPENSSL_NO_DEPRECATED -unsigned long (*CRYPTO_get_id_callback(void))(void) - { - return(id_callback); - } - -void CRYPTO_set_id_callback(unsigned long (*func)(void)) - { - id_callback=func; - } - -unsigned long CRYPTO_thread_id(void) - { - unsigned long ret=0; - - if (id_callback == NULL) - { -#ifdef OPENSSL_SYS_WIN16 - ret=(unsigned long)GetCurrentTask(); -#elif defined(OPENSSL_SYS_WIN32) - ret=(unsigned long)GetCurrentThreadId(); -#elif defined(GETPID_IS_MEANINGLESS) - ret=1L; -#elif defined(OPENSSL_SYS_BEOS) - ret=(unsigned long)find_thread(NULL); -#else - ret=(unsigned long)getpid(); -#endif - } - else - ret=id_callback(); - return(ret); - } -#endif - -void CRYPTO_lock(int mode, int type, const char *file, int line) - { -#ifdef LOCK_DEBUG - { - CRYPTO_THREADID id; - char *rw_text,*operation_text; - - if (mode & CRYPTO_LOCK) - operation_text="lock "; - else if (mode & CRYPTO_UNLOCK) - operation_text="unlock"; - else - operation_text="ERROR "; - - if (mode & CRYPTO_READ) - rw_text="r"; - else if (mode & CRYPTO_WRITE) - rw_text="w"; - else - rw_text="ERROR"; - - CRYPTO_THREADID_current(&id); - fprintf(stderr,"lock:%08lx:(%s)%s %-18s %s:%d\n", - CRYPTO_THREADID_hash(&id), rw_text, operation_text, - CRYPTO_get_lock_name(type), file, line); - } -#endif - if (type < 0) - { - if (dynlock_lock_callback != NULL) - { - struct CRYPTO_dynlock_value *pointer - = CRYPTO_get_dynlock_value(type); - - OPENSSL_assert(pointer != NULL); - - dynlock_lock_callback(mode, pointer, file, line); - - CRYPTO_destroy_dynlockid(type); - } - } - else - if (locking_callback != NULL) - locking_callback(mode,type,file,line); - } - -int CRYPTO_add_lock(int *pointer, int amount, int type, const char *file, - int line) - { - int ret = 0; - - if (add_lock_callback != NULL) - { -#ifdef LOCK_DEBUG - int before= *pointer; -#endif - - ret=add_lock_callback(pointer,amount,type,file,line); -#ifdef LOCK_DEBUG - { - CRYPTO_THREADID id; - CRYPTO_THREADID_current(&id); - fprintf(stderr,"ladd:%08lx:%2d+%2d->%2d %-18s %s:%d\n", - CRYPTO_THREADID_hash(&id), before,amount,ret, - CRYPTO_get_lock_name(type), - file,line); - } -#endif - } - else - { - CRYPTO_lock(CRYPTO_LOCK|CRYPTO_WRITE,type,file,line); - - ret= *pointer+amount; -#ifdef LOCK_DEBUG - { - CRYPTO_THREADID id; - CRYPTO_THREADID_current(&id); - fprintf(stderr,"ladd:%08lx:%2d+%2d->%2d %-18s %s:%d\n", - CRYPTO_THREADID_hash(&id), - *pointer,amount,ret, - CRYPTO_get_lock_name(type), - file,line); - } -#endif - *pointer=ret; - CRYPTO_lock(CRYPTO_UNLOCK|CRYPTO_WRITE,type,file,line); - } - return(ret); - } - -const char *CRYPTO_get_lock_name(int type) - { - if (type < 0) - return("dynamic"); - else if (type < CRYPTO_NUM_LOCKS) - return(lock_names[type]); - else if (type-CRYPTO_NUM_LOCKS > sk_STRING_num(app_locks)) - return("ERROR"); - else - return(sk_STRING_value(app_locks,type-CRYPTO_NUM_LOCKS)); - } - #if defined(__i386) || defined(__i386__) || defined(_M_IX86) || \ defined(__INTEL__) || \ defined(__x86_64) || defined(__x86_64__) || defined(_M_AMD64) || defined(_M_X64) -unsigned int OPENSSL_ia32cap_P[2]; +extern unsigned int OPENSSL_ia32cap_P[4]; unsigned int *OPENSSL_ia32cap_loc(void) { return OPENSSL_ia32cap_P; } #if defined(OPENSSL_CPUID_OBJ) && !defined(OPENSSL_NO_ASM) && !defined(I386_ONLY) @@ -673,21 +137,35 @@ typedef unsigned long long IA32CAP; #endif void OPENSSL_cpuid_setup(void) { static int trigger=0; - IA32CAP OPENSSL_ia32_cpuid(void); + IA32CAP OPENSSL_ia32_cpuid(unsigned int *); IA32CAP vec; char *env; if (trigger) return; trigger=1; - if ((env=getenv("OPENSSL_ia32cap"))) + if ((env=getenv("OPENSSL_ia32cap"))) { + int off = (env[0]=='~')?1:0; #if defined(_WIN32) - { if (!sscanf(env,"%I64i",&vec)) vec = strtoul(env,NULL,0); } + if (!sscanf(env+off,"%I64i",&vec)) vec = strtoul(env+off,NULL,0); #else - vec = strtoull(env,NULL,0); + if (!sscanf(env+off,"%lli",(long long *)&vec)) vec = strtoul(env+off,NULL,0); #endif + if (off) vec = OPENSSL_ia32_cpuid(OPENSSL_ia32cap_P)&~vec; + else if (env[0]==':') vec = OPENSSL_ia32_cpuid(OPENSSL_ia32cap_P); + + OPENSSL_ia32cap_P[2] = 0; + if ((env=strchr(env,':'))) { + unsigned int vecx; + env++; + off = (env[0]=='~')?1:0; + vecx = strtoul(env+off,NULL,0); + if (off) OPENSSL_ia32cap_P[2] &= ~vecx; + else OPENSSL_ia32cap_P[2] = vecx; + } + } else - vec = OPENSSL_ia32_cpuid(); + vec = OPENSSL_ia32_cpuid(OPENSSL_ia32cap_P); /* * |(1<<10) sets a reserved bit to signal that variable @@ -697,6 +175,8 @@ void OPENSSL_cpuid_setup(void) OPENSSL_ia32cap_P[0] = (unsigned int)vec|(1<<10); OPENSSL_ia32cap_P[1] = (unsigned int)(vec>>32); } +#else +unsigned int OPENSSL_ia32cap_P[4]; #endif #else @@ -711,6 +191,8 @@ void OPENSSL_cpuid_setup(void) {} #ifdef __CYGWIN__ /* pick DLL_[PROCESS|THREAD]_[ATTACH|DETACH] definitions */ #include +/* this has side-effect of _WIN32 getting defined, which otherwise + * is mutually exclusive with __CYGWIN__... */ #endif /* All we really need to do is remove the 'error' state when a thread @@ -742,7 +224,6 @@ BOOL WINAPI DllMain(HINSTANCE hinstDLL, DWORD fdwReason, case DLL_THREAD_ATTACH: break; case DLL_THREAD_DETACH: - ERR_remove_state(0); break; case DLL_PROCESS_DETACH: break; @@ -753,12 +234,35 @@ BOOL WINAPI DllMain(HINSTANCE hinstDLL, DWORD fdwReason, #if defined(_WIN32) && !defined(__CYGWIN__) #include +#include +#ifdef __WATCOMC__ +#if defined(_UNICODE) || defined(__UNICODE__) +#define _vsntprintf _vsnwprintf +#else +#define _vsntprintf _vsnprintf +#endif +#endif +#ifdef _MSC_VER +#define alloca _alloca +#endif #if defined(_WIN32_WINNT) && _WIN32_WINNT>=0x0333 int OPENSSL_isservice(void) { HWINSTA h; DWORD len; WCHAR *name; + static union { void *p; int (*f)(void); } _OPENSSL_isservice = { NULL }; + + if (_OPENSSL_isservice.p == NULL) { + HANDLE h = GetModuleHandle(NULL); + if (h != NULL) + _OPENSSL_isservice.p = GetProcAddress(h,"_OPENSSL_isservice"); + if (_OPENSSL_isservice.p == NULL) + _OPENSSL_isservice.p = (void *)-1; + } + + if (_OPENSSL_isservice.p != (void *)-1) + return (*_OPENSSL_isservice.f)(); (void)GetDesktopWindow(); /* return value is ignored */ @@ -771,11 +275,7 @@ int OPENSSL_isservice(void) if (len>512) return -1; /* paranoia */ len++,len&=~1; /* paranoia */ -#ifdef _MSC_VER - name=(WCHAR *)_alloca(len+sizeof(WCHAR)); -#else name=(WCHAR *)alloca(len+sizeof(WCHAR)); -#endif if (!GetUserObjectInformationW (h,UOI_NAME,name,len,&len)) return -1; @@ -806,8 +306,12 @@ void OPENSSL_showfatal (const char *fmta,...) if ((h=GetStdHandle(STD_ERROR_HANDLE)) != NULL && GetFileType(h)!=FILE_TYPE_UNKNOWN) { /* must be console application */ + int len; + DWORD out; + va_start (ap,fmta); - vfprintf (stderr,fmta,ap); + len=_vsnprintf((char *)buf,sizeof(buf),fmta,ap); + WriteFile(h,buf,len<0?sizeof(buf):(DWORD)len,&out,NULL); va_end (ap); return; } @@ -820,11 +324,7 @@ void OPENSSL_showfatal (const char *fmta,...) size_t len_0=strlen(fmta)+1,i; WCHAR *fmtw; -#ifdef _MSC_VER - fmtw = (WCHAR *)_alloca (len_0*sizeof(WCHAR)); -#else - fmtw = (WCHAR *)alloca (len_0*sizeof(WCHAR)); -#endif + fmtw = (WCHAR *)alloca(len_0*sizeof(WCHAR)); if (fmtw == NULL) { fmt=(const TCHAR *)L"no stack?"; break; } #ifndef OPENSSL_NO_MULTIBYTE @@ -857,7 +357,7 @@ void OPENSSL_showfatal (const char *fmta,...) #if defined(_WIN32_WINNT) && _WIN32_WINNT>=0x0333 /* this -------------v--- guards NT-specific calls */ - if (GetVersion() < 0x80000000 && OPENSSL_isservice()) + if (check_winnt() && OPENSSL_isservice() > 0) { HANDLE h = RegisterEventSource(0,_T("OPENSSL")); const TCHAR *pmsg=buf; ReportEvent(h,EVENTLOG_ERROR_TYPE,0,0,0,1,0,&pmsg,0); @@ -883,7 +383,30 @@ void OpenSSLDie(const char *file,int line,const char *assertion) OPENSSL_showfatal( "%s(%d): OpenSSL internal error, assertion failed: %s\n", file,line,assertion); +#if !defined(_WIN32) || defined(__CYGWIN__) abort(); +#else + /* Win32 abort() customarily shows a dialog, but we just did that... */ +#if !defined(_WIN32_WCE) + raise(SIGABRT); +#endif + _exit(3); +#endif } +#ifndef OPENSSL_FIPSCANISTER void *OPENSSL_stderr(void) { return stderr; } +#endif + +int CRYPTO_memcmp(const void *in_a, const void *in_b, size_t len) + { + size_t i; + const unsigned char *a = in_a; + const unsigned char *b = in_b; + unsigned char x = 0; + + for (i = 0; i < len; i++) + x |= a[i] ^ b[i]; + + return x; + }