Problem - Kevin Tafuro

if (pIssuer) {
if (!(pCACert = SpcLookupCACert(pIssuer))) return 0;
if (pCACert->lpszCRLURL) {
lpszURL = (LPSTR)LocalAlloc(LMEM_FIXED, lstrlenA(pCACert->lpszCRLURL) + 1);
if (!lpszURL) return 0;
lstrcpy(lpszURL, pCACert->lpszCRLURL);
return lpszURL;
}
}
return 0;
}
The worker function RetrieveWebData( ) is a wrapper around the WinInet API to
retrieve the CRLdata from an HTTP or FTP server, depending on the URL. It simply
establishes a connection to the server, retrieves the data if it can, and returns the
data that was retrieved to the caller. The CRLdata is dynamically allocated with
LocalAlloc( ), and it is expected that the caller will free the data with LocalFree( )
when it is no longer needed. (The WinInet API is discussed in detail in Recipe 9.4.)
static BYTE *RetrieveWebData(LPSTR lpszURL, DWORD *lpdwDataLength) {
DWORD dwContentLength, dwFlags, dwNumberOfBytesRead,
dwNumberOfBytesToRead;
LPVOID lpBuffer, lpFullBuffer, lpNewBuffer;
HINTERNET hRequest, hSession;
hSession = InternetOpen(TEXT("Secure Programming Cookbook Recipe 10.11"),
INTERNET_OPEN_TYPE_PROXY, 0, 0, 0);
if (!hSession) return 0;
dwFlags = INTERNET_FLAG_DONT_CACHE | INTERNET_FLAG_IGNORE_REDIRECT_TO_HTTP |
INTERNET_FLAG_IGNORE_REDIRECT_TO_HTTPS | INTERNET_FLAG_NO_COOKIES |
INTERNET_FLAG_NO_UI | INTERNET_FLAG_PASSIVE;
hRequest = InternetOpenUrl(hSession, lpszURL, 0, 0, dwFlags, 0);
if (!hRequest) {
InternetCloseHandle(hSession);
return 0;
}
dwContentLength = 0;
dwNumberOfBytesToRead = 1024;
lpFullBuffer = lpBuffer = LocalAlloc(LMEM_FIXED, dwNumberOfBytesToRead);
while (InternetReadFile(hRequest, lpBuffer, dwNumberOfBytesToRead,
&dwNumberOfBytesRead)) {
dwContentLength = dwContentLength + dwNumberOfBytesRead;
if (dwNumberOfBytesRead != dwNumberOfBytesToRead) break;
if (!(lpNewBuffer = LocalReAlloc(lpFullBuffer, dwContentLength +
dwNumberOfBytesToRead, 0))) {
LocalFree(lpFullBuffer);
InternetCloseHandle(hRequest);
InternetCloseHandle(hSession);
return 0;
}
560 | Chapter 10: Public Key Infrastructure
This is the Title of the Book, eMatter Edition
Copyright © 2007 O’Reilly & Associates, Inc. All rights reserved.