{"id":1424,"date":"2015-06-04T11:48:15","date_gmt":"2015-06-04T03:48:15","guid":{"rendered":"http:\/\/blog.dynox.cn\/?p=1424"},"modified":"2016-02-26T13:33:37","modified_gmt":"2016-02-26T05:33:37","slug":"security-enhanced-crt%e8%be%b9%e7%95%8c%e4%b8%8e%e6%bd%9c%e8%a7%84%e5%88%99","status":"publish","type":"post","link":"https:\/\/blog.dynox.cn\/?p=1424","title":{"rendered":"Security-Enhanced CRT,\u8fb9\u754c\u4e0e\u6f5c\u89c4\u5219"},"content":{"rendered":"

<\/em><\/strong>Windows Security-Enhanced CRT \u76f8\u5173\u51fd\u6570(\u5373_s\u540e\u8f8d\u51fd\u6570)\u5e76\u4e0d\u662f\u5bf9\u8001\u51fd\u6570\u7684\u76f4\u63a5\u66ff\u4ee3\uff0c\u5176\u4e2d\u4e0d\u4ec5\u6709\u66f4\u4e25\u683c\u7684\u53c2\u6570\u68c0\u67e5\uff0c\u8fd8\u4f1a\u6709buffer\u7684\u91cd\u7f6e\u64cd\u4f5c\u7b49\uff0c\u4f7f\u7528\u7684\u65f6\u5019\u8981\u683c\u5916\u5c0f\u5fc3\uff0c\u4e00\u5b9a\u8981\u4ed4\u7ec6\u9605\u8bfbMSDN\u63cf\u8ff0\u6216\u8005VC runtime\u6e90\u7801 (\u4ee5Visual Studio 2008\u4e3a\u4f8b\uff1a C:\\Program Files (x86)\\Microsoft Visual Studio 9.0\\VC\\crt\\src)\u3002<\/span><\/p>

\u4e0b\u9762\u4e0d\u59a8\u6d4b\u8bd53\u4e2a\u4ee3\u7801\u7247\u6bb5\uff1a <\/span><\/p>

\u6d4b\u8bd5\u4ee3\u7801\u3010C1\u3011\uff1a<\/span><\/p>

void main() {
    char dst1[8];
    memcpy(dst1, NULL, 0);
    memcpy(NULL, NULL, 0);
}<\/font><\/span><\/p>

\u6d4b\u8bd5\u4ee3\u7801\u3010C2\u3011:<\/span><\/p>

void main() {<\/font><\/span><\/p>

    char dst1[8];<\/font><\/span><\/p>

    memcpy_s(dst1, 8, NULL, 0);
    memcpy_s(NULL, 0, NULL, 0);
    char *dst2 = (char *)malloc(0);
    if (dst2) {
        memcpy_s(dst2, 0, NULL, 0);
    free(dst2);
    }
}<\/font><\/span><\/p>

\u6d4b\u8bd5\u4ee3\u7801\u3010C3\u3011:<\/span><\/p>

void main() {<\/font><\/span><\/p>

    char dst1[8];<\/font><\/span><\/p>

    memcpy_s(NULL, 0, dst1, 8);<\/font><\/span><\/p>

    char *dst2 = (char *)malloc(0);
    if (dst2) {
        memcpy_s(dst2, 0, dst1, 8);
        free(dst2);
    }
}<\/font><\/span><\/p>

\u8fd9\u51e0\u6bb5\u4ee3\u7801\u5b9e\u9645\u4e0a\u4ec0\u4e48\u4e5f\u6ca1\u6709\u505a\uff0c\u53ea\u662f\u53c2\u6570\u6709\u53d8\u5316\u800c\u5df2\uff0c\u4f46\u6d4b\u8bd5\u4e2d\u4f1a\u53d1\u73b0\u3010C3\u3011\u4f1a\u5bfc\u81f4\u7a0b\u5e8f\u5d29\u6e83\u3002\u5177\u4f53\u539f\u56e0\u5c31\u662f\u56e0\u4e3amemcpy_s\u8fdb\u884c\u4e86\u66f4\u4e25\u683c\u7684\u53c2\u6570\u68c0\u6d4b\uff0c\u53ef\u5bf9\u53c2\u8003memcpy_s\u7684\u6e90\u7801\uff0c\u5f15\u7528\u81eaVisual Studio 2008 runtime source memcpy_s.c:<\/span><\/p>

\/***
*  memcpy_s.c - contains memcpy_s routine
*
*       Copyright (c) Microsoft Corporation. All rights reserved.
*
*  Purpose:
*       memcpy_s() copies a source memory buffer to a destination buffer.
*       Overlapping buffers are not treated specially, so propagation may occur.
*
*******************************************************************\/<\/font><\/span><\/p>

#include <cruntime.h>
#include <string.h>
#include <internal.h><\/font><\/span><\/p>

\/***
*  memcpy_s - Copy source buffer to destination buffer
*
*  Purpose:
*       memcpy_s() copies a source memory buffer to a destination memory buffer.
*       This routine does NOT recognize overlapping buffers, and thus can lead
*       to propagation.
*
*       For cases where propagation must be avoided, memmove_s() must be used.
*
*  Entry:
*       void *dst = pointer to destination buffer
*       size_t sizeInBytes = size in bytes of the destination buffer
*       const void *src = pointer to source buffer
*       size_t count = number of bytes to copy
*
*  Exit:
*       Returns 0 if everything is ok, else return the error code.
*
*  Exceptions:
*       Input parameters are validated. Refer to the validation section of the function.
*       On error, the error code is returned and the destination buffer is zeroed.
*
*******************************************************************\/<\/font><\/span><\/p>

errno_t __cdecl memcpy_s(
    void * dst,
    size_t sizeInBytes,
    const void * src,
    size_t count
)
{
    if (count == 0)
    {
        \/* nothing to do *\/
        return 0;
    }<\/font><\/span><\/p>

    \/* validation section *\/
    _VALIDATE_RETURN_ERRCODE(dst != NULL, EINVAL);
    if (src == NULL || sizeInBytes < count)
    {
        \/* zeroes the destination buffer *\/
        memset(dst, 0, sizeInBytes);<\/font><\/span><\/p>

        _VALIDATE_RETURN_ERRCODE(src != NULL, EINVAL);
        _VALIDATE_RETURN_ERRCODE(sizeInBytes >= count, ERANGE);
        \/* useless, but prefast is confused *\/
        return EINVAL;
    }<\/font><\/span><\/p>

    memcpy(dst, src, count);
    return 0;
}<\/font><\/span><\/p>

<\/font><\/span><\/p>

\u53c2\u8003\u9605\u8bfb\uff1a
<\/span><\/p>

1\uff0c <\/span><\/span>_snwprintf_s\u7684\u6f5c\u89c4\u5219<\/span><\/span>\uff1a <\/span><\/span>https:\/\/blog.dynox.cn\/?p=791<\/span><\/span><\/a>
2,   Security Features in the CRT:
<\/span>      https:\/\/msdn.microsoft.com\/zh-cn\/library\/vstudio\/8ef0s5kh(v=vs.110).aspx<\/a><\/span><\/span><\/h4><\/div>","protected":false},"excerpt":{"rendered":"

Windows Security-Enhanced CRT \u76f8\u5173\u51fd\u6570(\u5373_s\u540e\u8f8d\u51fd\u6570)\u5e76\u4e0d\u662f\u5bf9\u8001\u51fd\u6570\u7684\u76f4\u63a5\u66ff\u4ee3 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"ngg_post_thumbnail":0,"footnotes":""},"categories":[9],"tags":[557,558,356,357],"views":1942,"_links":{"self":[{"href":"https:\/\/blog.dynox.cn\/index.php?rest_route=\/wp\/v2\/posts\/1424"}],"collection":[{"href":"https:\/\/blog.dynox.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.dynox.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.dynox.cn\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.dynox.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1424"}],"version-history":[{"count":7,"href":"https:\/\/blog.dynox.cn\/index.php?rest_route=\/wp\/v2\/posts\/1424\/revisions"}],"predecessor-version":[{"id":1470,"href":"https:\/\/blog.dynox.cn\/index.php?rest_route=\/wp\/v2\/posts\/1424\/revisions\/1470"}],"wp:attachment":[{"href":"https:\/\/blog.dynox.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1424"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.dynox.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1424"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.dynox.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1424"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}