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 /* This Source Code Form is subject to the terms of the Mozilla Public

  * License, v. 2.0. If a copy of the MPL was not distributed with this

  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

 /*

  * secport.c - portability interfaces for security libraries

  *

  * This file abstracts out libc functionality that libsec depends on

  * 

  * NOTE - These are not public interfaces

  */

 #include "seccomon.h"

 #include "prmem.h"

 #include "prerror.h"

 #include "plarena.h"

 #include "secerr.h"

 #include "prmon.h"

 #include "nssilock.h"

 #include "secport.h"

 #include "prenv.h"

 #ifdef DEBUG

 #define THREADMARK

 #endif /* DEBUG */

 #ifdef THREADMARK

 #include "prthread.h"

 #endif /* THREADMARK */

 #if defined(XP_UNIX) || defined(XP_OS2) || defined(XP_BEOS)

 #include <stdlib.h>

 #else

 #include "wtypes.h"

 #endif

 #define SET_ERROR_CODE	/* place holder for code to set PR error code. */

 #ifdef THREADMARK

 typedef struct threadmark_mark_str {

   struct threadmark_mark_str *next;

   void *mark;

 } threadmark_mark;

 #endif /* THREADMARK */

 /* The value of this magic must change each time PORTArenaPool changes. */

 #define ARENAPOOL_MAGIC 0xB8AC9BDF 

 typedef struct PORTArenaPool_str {

   PLArenaPool arena;

   PRUint32    magic;

   PRLock *    lock;

 #ifdef THREADMARK

   PRThread *marking_thread;

   threadmark_mark *first_mark;

 #endif

 } PORTArenaPool;

 /* count of allocation failures. */

 unsigned long port_allocFailures;

 /* locations for registering Unicode conversion functions.  

  * XXX is this the appropriate location?  or should they be

  *     moved to client/server specific locations?

  */

 PORTCharConversionFunc ucs4Utf8ConvertFunc;

 PORTCharConversionFunc ucs2Utf8ConvertFunc;

 PORTCharConversionWSwapFunc  ucs2AsciiConvertFunc;

 /* NSPR memory allocation functions (PR_Malloc, PR_Calloc, and PR_Realloc)

  * use the PRUint32 type for the size parameter. Before we pass a size_t or

  * unsigned long size to these functions, we need to ensure it is <= half of

  * the maximum PRUint32 value to avoid truncation and catch a negative size.

  */

 #define MAX_SIZE (PR_UINT32_MAX >> 1)

 void *

 PORT_Alloc(size_t bytes)

 {

     void *rv = NULL;

     if (bytes <= MAX_SIZE) {

 	/* Always allocate a non-zero amount of bytes */

 	rv = PR_Malloc(bytes ? bytes : 1);

     }

     if (!rv) {

 	++port_allocFailures;

 	PORT_SetError(SEC_ERROR_NO_MEMORY);

     }

     return rv;

 }

 void *

 PORT_Realloc(void *oldptr, size_t bytes)

 {

     void *rv = NULL;

     if (bytes <= MAX_SIZE) {

 	rv = PR_Realloc(oldptr, bytes);

     }

     if (!rv) {

 	++port_allocFailures;

 	PORT_SetError(SEC_ERROR_NO_MEMORY);

     }

     return rv;

 }

 void *

 PORT_ZAlloc(size_t bytes)

 {

     void *rv = NULL;

     if (bytes <= MAX_SIZE) {

 	/* Always allocate a non-zero amount of bytes */

 	rv = PR_Calloc(1, bytes ? bytes : 1);

     }

     if (!rv) {

 	++port_allocFailures;

 	PORT_SetError(SEC_ERROR_NO_MEMORY);

     }

     return rv;

 }

 void

 PORT_Free(void *ptr)

 {

     if (ptr) {

 	PR_Free(ptr);

     }

 }

 void

 PORT_ZFree(void *ptr, size_t len)

 {

     if (ptr) {

 	memset(ptr, 0, len);

 	PR_Free(ptr);

     }

 }

 char *

 PORT_Strdup(const char *str)

 {

     size_t len = PORT_Strlen(str)+1;

     char *newstr;

     newstr = (char *)PORT_Alloc(len);

     if (newstr) {

         PORT_Memcpy(newstr, str, len);

     }

     return newstr;

 }

 void

 PORT_SetError(int value)

 {	

 #ifdef DEBUG_jp96085

     PORT_Assert(value != SEC_ERROR_REUSED_ISSUER_AND_SERIAL);

 #endif

     PR_SetError(value, 0);

     return;

 }

 int

 PORT_GetError(void)

 {

     return(PR_GetError());

 }

 /********************* Arena code follows *****************************

  * ArenaPools are like heaps.  The memory in them consists of large blocks,

  * called arenas, which are allocated from the/a system heap.  Inside an

  * ArenaPool, the arenas are organized as if they were in a stack.  Newly

  * allocated arenas are "pushed" on that stack.  When you attempt to

  * allocate memory from an ArenaPool, the code first looks to see if there

  * is enough unused space in the top arena on the stack to satisfy your

  * request, and if so, your request is satisfied from that arena.

  * Otherwise, a new arena is allocated (or taken from NSPR's list of freed

  * arenas) and pushed on to the stack.  The new arena is always big enough

  * to satisfy the request, and is also at least a minimum size that is

  * established at the time that the ArenaPool is created.

  *

  * The ArenaMark function returns the address of a marker in the arena at

  * the top of the arena stack.  It is the address of the place in the arena

  * on the top of the arena stack from which the next block of memory will

  * be allocated.  Each ArenaPool has its own separate stack, and hence

  * marks are only relevant to the ArenaPool from which they are gotten.

  * Marks may be nested.  That is, a thread can get a mark, and then get

  * another mark.

  *

  * It is intended that all the marks in an ArenaPool may only be owned by a

  * single thread.  In DEBUG builds, this is enforced.  In non-DEBUG builds,

  * it is not.  In DEBUG builds, when a thread gets a mark from an

  * ArenaPool, no other thread may acquire a mark in that ArenaPool while

  * that mark exists, that is, until that mark is unmarked or released.

  * Therefore, it is important that every mark be unmarked or released when

  * the creating thread has no further need for exclusive ownership of the

  * right to manage the ArenaPool.

  *

  * The ArenaUnmark function discards the ArenaMark at the address given,

  * and all marks nested inside that mark (that is, acquired from that same

  * ArenaPool while that mark existed).   It is an error for a thread other

  * than the mark's creator to try to unmark it.  When a thread has unmarked

  * all its marks from an ArenaPool, then another thread is able to set

  * marks in that ArenaPool.  ArenaUnmark does not deallocate (or "pop") any

  * memory allocated from the ArenaPool since the mark was created.

  *

  * ArenaRelease "pops" the stack back to the mark, deallocating all the

  * memory allocated from the arenas in the ArenaPool since that mark was

  * created, and removing any arenas from the ArenaPool that have no

  * remaining active allocations when that is done.  It implicitly releases

  * any marks nested inside the mark being explicitly released.  It is the

  * only operation, other than destroying the arenapool, that potentially

  * reduces the number of arenas on the stack.  Otherwise, the stack grows

  * until the arenapool is destroyed, at which point all the arenas are

  * freed or returned to a "free arena list", depending on their sizes.

  */

 PLArenaPool *

 PORT_NewArena(unsigned long chunksize)

 {

     PORTArenaPool *pool;

     if (chunksize > MAX_SIZE) {

 	PORT_SetError(SEC_ERROR_NO_MEMORY);

 	return NULL;

     }

     pool = PORT_ZNew(PORTArenaPool);

     if (!pool) {

 	return NULL;

     }

     pool->magic = ARENAPOOL_MAGIC;

     pool->lock = PZ_NewLock(nssILockArena);

     if (!pool->lock) {

 	++port_allocFailures;

 	PORT_Free(pool);

 	return NULL;

     }

     PL_InitArenaPool(&pool->arena, "security", chunksize, sizeof(double));

     return(&pool->arena);

 }

 void *

 PORT_ArenaAlloc(PLArenaPool *arena, size_t size)

 {

     void *p = NULL;

     PORTArenaPool *pool = (PORTArenaPool *)arena;

     if (size <= 0) {

 	size = 1;

     }

     if (size > MAX_SIZE) {

 	/* you lose. */

     } else 

     /* Is it one of ours?  Assume so and check the magic */

     if (ARENAPOOL_MAGIC == pool->magic ) {

 	PZ_Lock(pool->lock);

 #ifdef THREADMARK

         /* Most likely one of ours.  Is there a thread id? */

 	if (pool->marking_thread  &&

 	    pool->marking_thread != PR_GetCurrentThread() ) {

 	    /* Another thread holds a mark in this arena */

 	    PZ_Unlock(pool->lock);

 	    PORT_SetError(SEC_ERROR_NO_MEMORY);

 	    PORT_Assert(0);

 	    return NULL;

 	} /* tid != null */

 #endif /* THREADMARK */

 	PL_ARENA_ALLOCATE(p, arena, size);

 	PZ_Unlock(pool->lock);

     } else {

 	PL_ARENA_ALLOCATE(p, arena, size);

     }

     if (!p) {

 	++port_allocFailures;

 	PORT_SetError(SEC_ERROR_NO_MEMORY);

     }

     return(p);

 }

 void *

 PORT_ArenaZAlloc(PLArenaPool *arena, size_t size)

 {

     void *p;

     if (size <= 0)

         size = 1;

     p = PORT_ArenaAlloc(arena, size);

     if (p) {

 	PORT_Memset(p, 0, size);

     }

     return(p);

 }

 /*

  * If zero is true, zeroize the arena memory before freeing it.

  */

 void

 PORT_FreeArena(PLArenaPool *arena, PRBool zero)

 {

     PORTArenaPool *pool = (PORTArenaPool *)arena;

     PRLock *       lock = (PRLock *)0;

     size_t         len  = sizeof *arena;

     static PRBool  checkedEnv = PR_FALSE;

     static PRBool  doFreeArenaPool = PR_FALSE;

     if (!pool)

     	return;

     if (ARENAPOOL_MAGIC == pool->magic ) {

 	len  = sizeof *pool;

 	lock = pool->lock;

 	PZ_Lock(lock);

     }

     if (!checkedEnv) {

 	/* no need for thread protection here */

 	doFreeArenaPool = (PR_GetEnv("NSS_DISABLE_ARENA_FREE_LIST") == NULL);

 	checkedEnv = PR_TRUE;

     }

     if (zero) {

 	PL_ClearArenaPool(arena, 0);

     }

     if (doFreeArenaPool) {

 	PL_FreeArenaPool(arena);

     } else {

 	PL_FinishArenaPool(arena);

     }

     PORT_ZFree(arena, len);

     if (lock) {

 	PZ_Unlock(lock);

 	PZ_DestroyLock(lock);

     }

 }

 void *

 PORT_ArenaGrow(PLArenaPool *arena, void *ptr, size_t oldsize, size_t newsize)

 {

     PORTArenaPool *pool = (PORTArenaPool *)arena;

     PORT_Assert(newsize >= oldsize);

     if (newsize > MAX_SIZE) {

 	PORT_SetError(SEC_ERROR_NO_MEMORY);

 	return NULL;

     }

     if (ARENAPOOL_MAGIC == pool->magic ) {

 	PZ_Lock(pool->lock);

 	/* Do we do a THREADMARK check here? */

 	PL_ARENA_GROW(ptr, arena, oldsize, ( newsize - oldsize ) );

 	PZ_Unlock(pool->lock);

     } else {

 	PL_ARENA_GROW(ptr, arena, oldsize, ( newsize - oldsize ) );

     }

     return(ptr);

 }

 void *

 PORT_ArenaMark(PLArenaPool *arena)

 {

     void * result;

     PORTArenaPool *pool = (PORTArenaPool *)arena;

     if (ARENAPOOL_MAGIC == pool->magic ) {

 	PZ_Lock(pool->lock);

 #ifdef THREADMARK

 	{

 	  threadmark_mark *tm, **pw;

 	  PRThread * currentThread = PR_GetCurrentThread();

 	    if (! pool->marking_thread ) {

 		/* First mark */

 		pool->marking_thread = currentThread;

 	    } else if (currentThread != pool->marking_thread ) {

 		PZ_Unlock(pool->lock);

 		PORT_SetError(SEC_ERROR_NO_MEMORY);

 		PORT_Assert(0);

 		return NULL;

 	    }

 	    result = PL_ARENA_MARK(arena);

 	    PL_ARENA_ALLOCATE(tm, arena, sizeof(threadmark_mark));

 	    if (!tm) {

 		PZ_Unlock(pool->lock);

 		PORT_SetError(SEC_ERROR_NO_MEMORY);

 		return NULL;

 	    }

 	    tm->mark = result;

 	    tm->next = (threadmark_mark *)NULL;

 	    pw = &pool->first_mark;

 	    while( *pw ) {

 		 pw = &(*pw)->next;

 	    }

 	    *pw = tm;

 	}

 #else /* THREADMARK */

 	result = PL_ARENA_MARK(arena);

 #endif /* THREADMARK */

 	PZ_Unlock(pool->lock);

     } else {

 	/* a "pure" NSPR arena */

 	result = PL_ARENA_MARK(arena);

     }

     return result;

 }

 /*

  * This function accesses the internals of PLArena, which is why it needs

  * to use the NSPR internal macro PL_MAKE_MEM_UNDEFINED before the memset

  * calls.

  *

  * We should move this function to NSPR as PL_ClearArenaAfterMark or add

  * a PL_ARENA_CLEAR_AND_RELEASE macro.

  *

  * TODO: remove the #ifdef PL_MAKE_MEM_UNDEFINED tests when NSPR 4.10+ is

  * widely available.

  */

 static void

 port_ArenaZeroAfterMark(PLArenaPool *arena, void *mark)

 {

     PLArena *a = arena->current;

     if (a->base <= (PRUword)mark && (PRUword)mark <= a->avail) {

 	/* fast path: mark falls in the current arena */

 #ifdef PL_MAKE_MEM_UNDEFINED

 	PL_MAKE_MEM_UNDEFINED(mark, a->avail - (PRUword)mark);

 #endif

 	memset(mark, 0, a->avail - (PRUword)mark);

     } else {

 	/* slow path: need to find the arena that mark falls in */

 	for (a = arena->first.next; a; a = a->next) {

 	    PR_ASSERT(a->base <= a->avail && a->avail <= a->limit);

 	    if (a->base <= (PRUword)mark && (PRUword)mark <= a->avail) {

 #ifdef PL_MAKE_MEM_UNDEFINED

 		PL_MAKE_MEM_UNDEFINED(mark, a->avail - (PRUword)mark);

 #endif

 		memset(mark, 0, a->avail - (PRUword)mark);

 		a = a->next;

 		break;

 	    }

 	}

 	for (; a; a = a->next) {

 	    PR_ASSERT(a->base <= a->avail && a->avail <= a->limit);

 #ifdef PL_MAKE_MEM_UNDEFINED

 	    PL_MAKE_MEM_UNDEFINED((void *)a->base, a->avail - a->base);

 #endif

 	    memset((void *)a->base, 0, a->avail - a->base);

 	}

     }

 }

 static void

 port_ArenaRelease(PLArenaPool *arena, void *mark, PRBool zero)

 {

     PORTArenaPool *pool = (PORTArenaPool *)arena;

     if (ARENAPOOL_MAGIC == pool->magic ) {

 	PZ_Lock(pool->lock);

 #ifdef THREADMARK

 	{

 	    threadmark_mark **pw, *tm;

 	    if (PR_GetCurrentThread() != pool->marking_thread ) {

 		PZ_Unlock(pool->lock);

 		PORT_SetError(SEC_ERROR_NO_MEMORY);

 		PORT_Assert(0);

 		return /* no error indication available */ ;

 	    }

 	    pw = &pool->first_mark;

 	    while( *pw && (mark != (*pw)->mark) ) {

 		pw = &(*pw)->next;

 	    }

 	    if (! *pw ) {

 		/* bad mark */

 		PZ_Unlock(pool->lock);

 		PORT_SetError(SEC_ERROR_NO_MEMORY);

 		PORT_Assert(0);

 		return /* no error indication available */ ;

 	    }

 	    tm = *pw;

 	    *pw = (threadmark_mark *)NULL;

 	    if (zero) {

 		port_ArenaZeroAfterMark(arena, mark);

 	    }

 	    PL_ARENA_RELEASE(arena, mark);

 	    if (! pool->first_mark ) {

 		pool->marking_thread = (PRThread *)NULL;

 	    }

 	}

 #else /* THREADMARK */

 	if (zero) {

 	    port_ArenaZeroAfterMark(arena, mark);

 	}

 	PL_ARENA_RELEASE(arena, mark);

 #endif /* THREADMARK */

 	PZ_Unlock(pool->lock);

     } else {

 	if (zero) {

 	    port_ArenaZeroAfterMark(arena, mark);

 	}

 	PL_ARENA_RELEASE(arena, mark);

     }

 }

 void

 PORT_ArenaRelease(PLArenaPool *arena, void *mark)

 {

     port_ArenaRelease(arena, mark, PR_FALSE);

 }

 /*

  * Zeroize the arena memory before releasing it.

  */

 void

 PORT_ArenaZRelease(PLArenaPool *arena, void *mark)

 {

     port_ArenaRelease(arena, mark, PR_TRUE);

 }

 void

 PORT_ArenaUnmark(PLArenaPool *arena, void *mark)

 {

 #ifdef THREADMARK

     PORTArenaPool *pool = (PORTArenaPool *)arena;

     if (ARENAPOOL_MAGIC == pool->magic ) {

 	threadmark_mark **pw, *tm;

 	PZ_Lock(pool->lock);

 	if (PR_GetCurrentThread() != pool->marking_thread ) {

 	    PZ_Unlock(pool->lock);

 	    PORT_SetError(SEC_ERROR_NO_MEMORY);

 	    PORT_Assert(0);

 	    return /* no error indication available */ ;

 	}

 	pw = &pool->first_mark;

 	while( ((threadmark_mark *)NULL != *pw) && (mark != (*pw)->mark) ) {

 	    pw = &(*pw)->next;

 	}

 	if ((threadmark_mark *)NULL == *pw ) {

 	    /* bad mark */

 	    PZ_Unlock(pool->lock);

 	    PORT_SetError(SEC_ERROR_NO_MEMORY);

 	    PORT_Assert(0);

 	    return /* no error indication available */ ;

 	}

 	tm = *pw;

 	*pw = (threadmark_mark *)NULL;

 	if (! pool->first_mark ) {

 	    pool->marking_thread = (PRThread *)NULL;

 	}

 	PZ_Unlock(pool->lock);

     }

 #endif /* THREADMARK */

 }

 char *

 PORT_ArenaStrdup(PLArenaPool *arena, const char *str) {

     int len = PORT_Strlen(str)+1;

     char *newstr;

     newstr = (char*)PORT_ArenaAlloc(arena,len);

     if (newstr) {

         PORT_Memcpy(newstr,str,len);

     }

     return newstr;

 }

 /********************** end of arena functions ***********************/

 /****************** unicode conversion functions ***********************/

 /*

  * NOTE: These conversion functions all assume that the multibyte

  * characters are going to be in NETWORK BYTE ORDER, not host byte

  * order.  This is because the only time we deal with UCS-2 and UCS-4

  * are when the data was received from or is going to be sent out

  * over the wire (in, e.g. certificates).

  */

 void

 PORT_SetUCS4_UTF8ConversionFunction(PORTCharConversionFunc convFunc)

 { 

     ucs4Utf8ConvertFunc = convFunc;

 }

 void

 PORT_SetUCS2_ASCIIConversionFunction(PORTCharConversionWSwapFunc convFunc)

 { 

     ucs2AsciiConvertFunc = convFunc;

 }

 void

 PORT_SetUCS2_UTF8ConversionFunction(PORTCharConversionFunc convFunc)

 { 

     ucs2Utf8ConvertFunc = convFunc;

 }

 PRBool 

 PORT_UCS4_UTF8Conversion(PRBool toUnicode, unsigned char *inBuf,

 			 unsigned int inBufLen, unsigned char *outBuf,

 			 unsigned int maxOutBufLen, unsigned int *outBufLen)

 {

     if(!ucs4Utf8ConvertFunc) {

       return sec_port_ucs4_utf8_conversion_function(toUnicode,

         inBuf, inBufLen, outBuf, maxOutBufLen, outBufLen);

     }

     return (*ucs4Utf8ConvertFunc)(toUnicode, inBuf, inBufLen, outBuf, 

 				  maxOutBufLen, outBufLen);

 }

 PRBool 

 PORT_UCS2_UTF8Conversion(PRBool toUnicode, unsigned char *inBuf,

 			 unsigned int inBufLen, unsigned char *outBuf,

 			 unsigned int maxOutBufLen, unsigned int *outBufLen)

 {

     if(!ucs2Utf8ConvertFunc) {

       return sec_port_ucs2_utf8_conversion_function(toUnicode,

         inBuf, inBufLen, outBuf, maxOutBufLen, outBufLen);

     }

     return (*ucs2Utf8ConvertFunc)(toUnicode, inBuf, inBufLen, outBuf, 

 				  maxOutBufLen, outBufLen);

 }

 PRBool 

 PORT_ISO88591_UTF8Conversion(const unsigned char *inBuf,

 			 unsigned int inBufLen, unsigned char *outBuf,

 			 unsigned int maxOutBufLen, unsigned int *outBufLen)

 {

     return sec_port_iso88591_utf8_conversion_function(inBuf, inBufLen,

       outBuf, maxOutBufLen, outBufLen);

 }

 PRBool 

 PORT_UCS2_ASCIIConversion(PRBool toUnicode, unsigned char *inBuf,

 			  unsigned int inBufLen, unsigned char *outBuf,

 			  unsigned int maxOutBufLen, unsigned int *outBufLen,

 			  PRBool swapBytes)

 {

     if(!ucs2AsciiConvertFunc) {

 	return PR_FALSE;

     }

     return (*ucs2AsciiConvertFunc)(toUnicode, inBuf, inBufLen, outBuf, 

 				  maxOutBufLen, outBufLen, swapBytes);

 }

 /* Portable putenv.  Creates/replaces an environment variable of the form

  *  envVarName=envValue

  */

 int

 NSS_PutEnv(const char * envVarName, const char * envValue)

 {

     SECStatus result = SECSuccess;

     char *    encoded;

     int       putEnvFailed;

 #ifdef _WIN32

     PRBool      setOK;

     setOK = SetEnvironmentVariable(envVarName, envValue);

     if (!setOK) {

         SET_ERROR_CODE

         return SECFailure;

     }

 #endif

     encoded = (char *)PORT_ZAlloc(strlen(envVarName) + 2 + strlen(envValue));

     strcpy(encoded, envVarName);

     strcat(encoded, "=");

     strcat(encoded, envValue);

     putEnvFailed = putenv(encoded); /* adopt. */

     if (putEnvFailed) {

         SET_ERROR_CODE

         result = SECFailure;

         PORT_Free(encoded);

     }

     return result;

 }

 /*

  * Perform a constant-time compare of two memory regions. The return value is

  * 0 if the memory regions are equal and non-zero otherwise.

  */

 int

 NSS_SecureMemcmp(const void *ia, const void *ib, size_t n)

 {

     const unsigned char *a = (const unsigned char*) ia;

     const unsigned char *b = (const unsigned char*) ib;

     size_t i;

     unsigned char r = 0;

     for (i = 0; i < n; ++i) {

         r |= *a++ ^ *b++;

     }

     return r;

 }