The Tor Browser: security/nss/lib/util/secitem.c@b8a032363ba2 (annotated)

security/nss/lib/util/secitem.c@b8a032363ba2 (annotated)

security/nss/lib/util/secitem.c

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /* 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/. */
 /*
  * Support routines for SECItem data structure.
  */
 #include "seccomon.h"
 #include "secitem.h"
 #include "secerr.h"
 #include "secport.h"
 SECItem *
 SECITEM_AllocItem(PLArenaPool *arena, SECItem *item, unsigned int len)
 {
     SECItem *result = NULL;
     void *mark = NULL;
     if (arena != NULL) {
 	mark = PORT_ArenaMark(arena);
     }
     if (item == NULL) {
 	if (arena != NULL) {
 	    result = PORT_ArenaZAlloc(arena, sizeof(SECItem));
 	} else {
 	    result = PORT_ZAlloc(sizeof(SECItem));
 	}
 	if (result == NULL) {
 	    goto loser;
 	}
     } else {
 	PORT_Assert(item->data == NULL);
 	result = item;
     }
     result->len = len;
     if (len) {
 	if (arena != NULL) {
 	    result->data = PORT_ArenaAlloc(arena, len);
 	} else {
 	    result->data = PORT_Alloc(len);
 	}
 	if (result->data == NULL) {
 	    goto loser;
 	}
     } else {
 	result->data = NULL;
     }
     if (mark) {
 	PORT_ArenaUnmark(arena, mark);
     }
     return(result);
 loser:
     if ( arena != NULL ) {
 	if (mark) {
 	    PORT_ArenaRelease(arena, mark);
 	}
 	if (item != NULL) {
 	    item->data = NULL;
 	    item->len = 0;
 	}
     } else {
 	if (result != NULL) {
 	    SECITEM_FreeItem(result, (item == NULL) ? PR_TRUE : PR_FALSE);
 	}
 	/*
 	 * If item is not NULL, the above has set item->data and
 	 * item->len to 0.
 	 */
     }
     return(NULL);
 }
 SECStatus
 SECITEM_ReallocItem(PLArenaPool *arena, SECItem *item, unsigned int oldlen,
 		    unsigned int newlen)
 {
     PORT_Assert(item != NULL);
     if (item == NULL) {
 	/* XXX Set error.  But to what? */
 	return SECFailure;
     }
     /*
      * If no old length, degenerate to just plain alloc.
      */
     if (oldlen == 0) {
 	PORT_Assert(item->data == NULL || item->len == 0);
 	if (newlen == 0) {
 	    /* Nothing to do.  Weird, but not a failure.  */
 	    return SECSuccess;
 	}
 	item->len = newlen;
 	if (arena != NULL) {
 	    item->data = PORT_ArenaAlloc(arena, newlen);
 	} else {
 	    item->data = PORT_Alloc(newlen);
 	}
     } else {
 	if (arena != NULL) {
 	    item->data = PORT_ArenaGrow(arena, item->data, oldlen, newlen);
 	} else {
 	    item->data = PORT_Realloc(item->data, newlen);
 	}
     }
     if (item->data == NULL) {
 	return SECFailure;
     }
     return SECSuccess;
 }
 SECStatus
 SECITEM_ReallocItemV2(PLArenaPool *arena, SECItem *item, unsigned int newlen)
 {
     unsigned char *newdata = NULL;
     PORT_Assert(item);
     if (!item) {
 	PORT_SetError(SEC_ERROR_INVALID_ARGS);
 	return SECFailure;
     }
     if (item->len == newlen) {
 	return SECSuccess;
     }
     if (!newlen) {
 	if (!arena) {
 	    PORT_Free(item->data);
 	}
 	item->data = NULL;
 	item->len = 0;
 	return SECSuccess;
     }
     if (!item->data) {
 	/* allocate fresh block of memory */
 	PORT_Assert(!item->len);
 	if (arena) {
 	    newdata = PORT_ArenaAlloc(arena, newlen);
 	} else {
 	    newdata = PORT_Alloc(newlen);
 	}
     } else {
 	/* reallocate or adjust existing block of memory */
 	if (arena) {
 	    if (item->len > newlen) {
 		/* There's no need to realloc a shorter block from the arena,
 		 * because it would result in using even more memory!
 		 * Therefore we'll continue to use the old block and
 		 * set the item to the shorter size.
 		 */
 		item->len = newlen;
 		return SECSuccess;
 	    }
 	    newdata = PORT_ArenaGrow(arena, item->data, item->len, newlen);
 	} else {
 	    newdata = PORT_Realloc(item->data, newlen);
 	}
     }
     if (!newdata) {
 	PORT_SetError(SEC_ERROR_NO_MEMORY);
 	return SECFailure;
     }
     item->len = newlen;
     item->data = newdata;
     return SECSuccess;
 }
 SECComparison
 SECITEM_CompareItem(const SECItem *a, const SECItem *b)
 {
     unsigned m;
     int rv;
     if (a == b)
     	return SECEqual;
     if (!a || !a->len || !a->data)
         return (!b || !b->len || !b->data) ? SECEqual : SECLessThan;
     if (!b || !b->len || !b->data)
     	return SECGreaterThan;
     m = ( ( a->len < b->len ) ? a->len : b->len );
     rv = PORT_Memcmp(a->data, b->data, m);
     if (rv) {
 	return rv < 0 ? SECLessThan : SECGreaterThan;
     }
     if (a->len < b->len) {
 	return SECLessThan;
     }
     if (a->len == b->len) {
 	return SECEqual;
     }
     return SECGreaterThan;
 }
 PRBool
 SECITEM_ItemsAreEqual(const SECItem *a, const SECItem *b)
 {
     if (a->len != b->len)
         return PR_FALSE;
     if (!a->len)
     	return PR_TRUE;
     if (!a->data || !b->data) {
         /* avoid null pointer crash. */
 	return (PRBool)(a->data == b->data);
     }
     return (PRBool)!PORT_Memcmp(a->data, b->data, a->len);
 }
 SECItem *
 SECITEM_DupItem(const SECItem *from)
 {
     return SECITEM_ArenaDupItem(NULL, from);
 }
 SECItem *
 SECITEM_ArenaDupItem(PLArenaPool *arena, const SECItem *from)
 {
     SECItem *to;
     if ( from == NULL ) {
 	return(NULL);
     }
     if ( arena != NULL ) {
 	to = (SECItem *)PORT_ArenaAlloc(arena, sizeof(SECItem));
     } else {
 	to = (SECItem *)PORT_Alloc(sizeof(SECItem));
     }
     if ( to == NULL ) {
 	return(NULL);
     }
     if ( arena != NULL ) {
 	to->data = (unsigned char *)PORT_ArenaAlloc(arena, from->len);
     } else {
 	to->data = (unsigned char *)PORT_Alloc(from->len);
     }
     if ( to->data == NULL ) {
 	PORT_Free(to);
 	return(NULL);
     }
     to->len = from->len;
     to->type = from->type;
     if ( to->len ) {
 	PORT_Memcpy(to->data, from->data, to->len);
     }
     return(to);
 }
 SECStatus
 SECITEM_CopyItem(PLArenaPool *arena, SECItem *to, const SECItem *from)
 {
     to->type = from->type;
     if (from->data && from->len) {
 	if ( arena ) {
 	    to->data = (unsigned char*) PORT_ArenaAlloc(arena, from->len);
 	} else {
 	    to->data = (unsigned char*) PORT_Alloc(from->len);
 	}
 	if (!to->data) {
 	    return SECFailure;
 	}
 	PORT_Memcpy(to->data, from->data, from->len);
 	to->len = from->len;
     } else {
 	/*
 	 * If from->data is NULL but from->len is nonzero, this function
 	 * will succeed.  Is this right?
 	 */
 	to->data = 0;
 	to->len = 0;
     }
     return SECSuccess;
 }
 void
 SECITEM_FreeItem(SECItem *zap, PRBool freeit)
 {
     if (zap) {
 	PORT_Free(zap->data);
 	zap->data = 0;
 	zap->len = 0;
 	if (freeit) {
 	    PORT_Free(zap);
 	}
     }
 }
 void
 SECITEM_ZfreeItem(SECItem *zap, PRBool freeit)
 {
     if (zap) {
 	PORT_ZFree(zap->data, zap->len);
 	zap->data = 0;
 	zap->len = 0;
 	if (freeit) {
 	    PORT_ZFree(zap, sizeof(SECItem));
 	}
     }
 }
 /* these reroutines were taken from pkix oid.c, which is supposed to
  * replace this file some day */
 /*
  * This is the hash function.  We simply XOR the encoded form with
  * itself in sizeof(PLHashNumber)-byte chunks.  Improving this
  * routine is left as an excercise for the more mathematically
  * inclined student.
  */
 PLHashNumber PR_CALLBACK
 SECITEM_Hash ( const void *key)
 {
     const SECItem *item = (const SECItem *)key;
     PLHashNumber rv = 0;
     PRUint8 *data = (PRUint8 *)item->data;
     PRUint32 i;
     PRUint8 *rvc = (PRUint8 *)&rv;
     for( i = 0; i < item->len; i++ ) {
         rvc[ i % sizeof(rv) ] ^= *data;
         data++;
     }
     return rv;
 }
 /*
  * This is the key-compare function.  It simply does a lexical
  * comparison on the item data.  This does not result in
  * quite the same ordering as the "sequence of numbers" order,
  * but heck it's only used internally by the hash table anyway.
  */
 PRIntn PR_CALLBACK
 SECITEM_HashCompare ( const void *k1, const void *k2)
 {
     const SECItem *i1 = (const SECItem *)k1;
     const SECItem *i2 = (const SECItem *)k2;
     return SECITEM_ItemsAreEqual(i1,i2);
 }
 SECItemArray *
 SECITEM_AllocArray(PLArenaPool *arena, SECItemArray *array, unsigned int len)
 {
     SECItemArray *result = NULL;
     void *mark = NULL;
     if (array != NULL && array->items != NULL) {
         PORT_Assert(0);
         PORT_SetError(SEC_ERROR_INVALID_ARGS);
         return NULL;
     }
     if (arena != NULL) {
         mark = PORT_ArenaMark(arena);
     }
     if (array == NULL) {
         if (arena != NULL) {
             result = PORT_ArenaZAlloc(arena, sizeof(SECItemArray));
         } else {
             result = PORT_ZAlloc(sizeof(SECItemArray));
         }
         if (result == NULL) {
             goto loser;
         }
     } else {
         result = array;
     }
     result->len = len;
     if (len) {
         if (arena != NULL) {
             result->items = PORT_ArenaZNewArray(arena, SECItem, len);
         } else {
             result->items = PORT_ZNewArray(SECItem, len);
         }
         if (result->items == NULL) {
             goto loser;
         }
     } else {
         result->items = NULL;
     }
     if (mark) {
         PORT_ArenaUnmark(arena, mark);
     }
     return result;
 loser:
     if ( arena != NULL ) {
         if (mark) {
             PORT_ArenaRelease(arena, mark);
         }
     } else {
         if (result != NULL && array == NULL) {
             PORT_Free(result);
         }
     }
     if (array != NULL) {
         array->items = NULL;
         array->len = 0;
     }
     return NULL;
 }
 static void
 secitem_FreeArray(SECItemArray *array, PRBool zero_items, PRBool freeit)
 {
     unsigned int i;
     if (!array || !array->len || !array->items)
         return;
     for (i = 0; i < array->len; ++i) {
         SECItem *item = &array->items[i];
         if (item->data) {
             if (zero_items) {
                 SECITEM_ZfreeItem(item, PR_FALSE);
             } else {
                 SECITEM_FreeItem(item, PR_FALSE);
             }
         }
     }
     PORT_Free(array->items);
     array->items = NULL;
     array->len = 0;
     if (freeit)
         PORT_Free(array);
 }
 void SECITEM_FreeArray(SECItemArray *array, PRBool freeit)
 {
     secitem_FreeArray(array, PR_FALSE, freeit);
 }
 void SECITEM_ZfreeArray(SECItemArray *array, PRBool freeit)
 {
     secitem_FreeArray(array, PR_TRUE, freeit);
 }
 SECItemArray *
 SECITEM_DupArray(PLArenaPool *arena, const SECItemArray *from)
 {
     SECItemArray *result;
     unsigned int i;
     /* Require a "from" array.
      * Reject an inconsistent "from" array with NULL data and nonzero length.
      * However, allow a "from" array of zero length.
      */
     if (!from || (!from->items && from->len))
         return NULL;
     result = SECITEM_AllocArray(arena, NULL, from->len);
     if (!result)
         return NULL;
     for (i = 0; i < from->len; ++i) {
         SECStatus rv = SECITEM_CopyItem(arena,
                                         &result->items[i], &from->items[i]);
         if (rv != SECSuccess) {
             SECITEM_ZfreeArray(result, PR_TRUE);
             return NULL;
         }
     }
     return result;
 }

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security/nss/lib/util/secitem.c@b8a032363ba2 (annotated)

security/nss/lib/util/secitem.c