Merge pull request #1448 from phkelley/development Avoid pre-Win7 WinHTTP self-redirect quirk
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358
diff --git a/src/common.h b/src/common.h
index 235da04..02d9ce9 100644
--- a/src/common.h
+++ b/src/common.h
@@ -29,9 +29,10 @@
# include "win32/msvc-compat.h"
# include "win32/mingw-compat.h"
# include "win32/error.h"
+# include "win32/version.h"
# ifdef GIT_THREADS
# include "win32/pthread.h"
-#endif
+# endif
#else
diff --git a/src/transports/winhttp.c b/src/transports/winhttp.c
index d4d0179..e502001 100644
--- a/src/transports/winhttp.c
+++ b/src/transports/winhttp.c
@@ -58,6 +58,7 @@ typedef struct {
const char *service_url;
const wchar_t *verb;
HINTERNET request;
+ wchar_t *request_uri;
char *chunk_buffer;
unsigned chunk_buffer_len;
HANDLE post_body;
@@ -145,10 +146,10 @@ static int winhttp_stream_connect(winhttp_stream *s)
winhttp_subtransport *t = OWNING_SUBTRANSPORT(s);
git_buf buf = GIT_BUF_INIT;
char *proxy_url = NULL;
- wchar_t url[GIT_WIN_PATH], ct[MAX_CONTENT_TYPE_LEN];
+ wchar_t ct[MAX_CONTENT_TYPE_LEN];
wchar_t *types[] = { L"*/*", NULL };
BOOL peerdist = FALSE;
- int error = -1;
+ int error = -1, wide_len;
/* Prepare URL */
git_buf_printf(&buf, "%s%s", t->path, s->service_url);
@@ -156,13 +157,31 @@ static int winhttp_stream_connect(winhttp_stream *s)
if (git_buf_oom(&buf))
return -1;
- git__utf8_to_16(url, GIT_WIN_PATH, git_buf_cstr(&buf));
+ /* Convert URL to wide characters */
+ wide_len = MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS,
+ git_buf_cstr(&buf), -1, NULL, 0);
+
+ if (!wide_len) {
+ giterr_set(GITERR_OS, "Failed to measure string for wide conversion");
+ goto on_error;
+ }
+
+ s->request_uri = git__malloc(wide_len * sizeof(wchar_t));
+
+ if (!s->request_uri)
+ goto on_error;
+
+ if (!MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS,
+ git_buf_cstr(&buf), -1, s->request_uri, wide_len)) {
+ giterr_set(GITERR_OS, "Failed to convert string to wide form");
+ goto on_error;
+ }
/* Establish request */
s->request = WinHttpOpenRequest(
t->connection,
s->verb,
- url,
+ s->request_uri,
NULL,
WINHTTP_NO_REFERER,
types,
@@ -179,19 +198,36 @@ static int winhttp_stream_connect(winhttp_stream *s)
if (proxy_url) {
WINHTTP_PROXY_INFO proxy_info;
- size_t wide_len;
+ wchar_t *proxy_wide;
+
+ /* Convert URL to wide characters */
+ wide_len = MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS,
+ proxy_url, -1, NULL, 0);
- git__utf8_to_16(url, GIT_WIN_PATH, proxy_url);
+ if (!wide_len) {
+ giterr_set(GITERR_OS, "Failed to measure string for wide conversion");
+ goto on_error;
+ }
- wide_len = wcslen(url);
+ proxy_wide = git__malloc(wide_len * sizeof(wchar_t));
+
+ if (!proxy_wide)
+ goto on_error;
+
+ if (!MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS,
+ proxy_url, -1, proxy_wide, wide_len)) {
+ giterr_set(GITERR_OS, "Failed to convert string to wide form");
+ git__free(proxy_wide);
+ goto on_error;
+ }
/* Strip any trailing forward slash on the proxy URL;
* WinHTTP doesn't like it if one is present */
- if (L'/' == url[wide_len - 1])
- url[wide_len - 1] = L'\0';
+ if (wide_len > 1 && L'/' == proxy_wide[wide_len - 2])
+ proxy_wide[wide_len - 2] = L'\0';
proxy_info.dwAccessType = WINHTTP_ACCESS_TYPE_NAMED_PROXY;
- proxy_info.lpszProxy = url;
+ proxy_info.lpszProxy = proxy_wide;
proxy_info.lpszProxyBypass = NULL;
if (!WinHttpSetOption(s->request,
@@ -199,8 +235,11 @@ static int winhttp_stream_connect(winhttp_stream *s)
&proxy_info,
sizeof(WINHTTP_PROXY_INFO))) {
giterr_set(GITERR_OS, "Failed to set proxy");
+ git__free(proxy_wide);
goto on_error;
}
+
+ git__free(proxy_wide);
}
/* Strip unwanted headers (X-P2P-PeerDist, X-P2P-PeerDistEx) that WinHTTP
@@ -348,8 +387,15 @@ static int winhttp_stream_read(
winhttp_stream *s = (winhttp_stream *)stream;
winhttp_subtransport *t = OWNING_SUBTRANSPORT(s);
DWORD dw_bytes_read;
+ char replay_count = 0;
replay:
+ /* Enforce a reasonable cap on the number of replays */
+ if (++replay_count >= 7) {
+ giterr_set(GITERR_NET, "Too many redirects or authentication replays");
+ return -1;
+ }
+
/* Connect if necessary */
if (!s->request && winhttp_stream_connect(s) < 0)
return -1;
@@ -445,10 +491,70 @@ replay:
WINHTTP_HEADER_NAME_BY_INDEX,
&status_code, &status_code_length,
WINHTTP_NO_HEADER_INDEX)) {
- giterr_set(GITERR_OS, "Failed to retreive status code");
+ giterr_set(GITERR_OS, "Failed to retrieve status code");
return -1;
}
+ /* The implementation of WinHTTP prior to Windows 7 will not
+ * redirect to an identical URI. Some Git hosters use self-redirects
+ * as part of their DoS mitigation strategy. Check first to see if we
+ * have a redirect status code, and that we haven't already streamed
+ * a post body. (We can't replay a streamed POST.) */
+ if (!s->chunked &&
+ (HTTP_STATUS_MOVED == status_code ||
+ HTTP_STATUS_REDIRECT == status_code ||
+ (HTTP_STATUS_REDIRECT_METHOD == status_code &&
+ get_verb == s->verb) ||
+ HTTP_STATUS_REDIRECT_KEEP_VERB == status_code)) {
+
+ /* Check for Windows 7. This workaround is only necessary on
+ * Windows Vista and earlier. Windows 7 is version 6.1. */
+ if (!git_has_win32_version(6, 1)) {
+ wchar_t *location;
+ DWORD location_length;
+ int redirect_cmp;
+
+ /* OK, fetch the Location header from the redirect. */
+ if (WinHttpQueryHeaders(s->request,
+ WINHTTP_QUERY_LOCATION,
+ WINHTTP_HEADER_NAME_BY_INDEX,
+ WINHTTP_NO_OUTPUT_BUFFER,
+ &location_length,
+ WINHTTP_NO_HEADER_INDEX) ||
+ GetLastError() != ERROR_INSUFFICIENT_BUFFER) {
+ giterr_set(GITERR_OS, "Failed to read Location header");
+ return -1;
+ }
+
+ location = git__malloc(location_length);
+ GITERR_CHECK_ALLOC(location);
+
+ if (!WinHttpQueryHeaders(s->request,
+ WINHTTP_QUERY_LOCATION,
+ WINHTTP_HEADER_NAME_BY_INDEX,
+ location,
+ &location_length,
+ WINHTTP_NO_HEADER_INDEX)) {
+ giterr_set(GITERR_OS, "Failed to read Location header");
+ git__free(location);
+ return -1;
+ }
+
+ /* Compare the Location header with the request URI */
+ redirect_cmp = wcscmp(location, s->request_uri);
+ git__free(location);
+
+ if (!redirect_cmp) {
+ /* Replay the request */
+ WinHttpCloseHandle(s->request);
+ s->request = NULL;
+ s->sent_request = 0;
+
+ goto replay;
+ }
+ }
+ }
+
/* Handle authentication failures */
if (HTTP_STATUS_DENIED == status_code &&
get_verb == s->verb && t->owner->cred_acquire_cb) {
@@ -747,6 +853,11 @@ static void winhttp_stream_free(git_smart_subtransport_stream *stream)
s->post_body = NULL;
}
+ if (s->request_uri) {
+ git__free(s->request_uri);
+ s->request_uri = NULL;
+ }
+
if (s->request) {
WinHttpCloseHandle(s->request);
s->request = NULL;
@@ -876,7 +987,7 @@ static int winhttp_receivepack(
{
/* WinHTTP only supports Transfer-Encoding: chunked
* on Windows Vista (NT 6.0) and higher. */
- s->chunked = LOBYTE(LOWORD(GetVersion())) >= 6;
+ s->chunked = git_has_win32_version(6, 0);
if (s->chunked)
s->parent.write = winhttp_stream_write_chunked;
diff --git a/src/win32/error.c b/src/win32/error.c
index 3851ff0..4a9a063 100644
--- a/src/win32/error.c
+++ b/src/win32/error.c
@@ -8,34 +8,70 @@
#include "common.h"
#include "error.h"
+#ifdef GIT_WINHTTP
+# include <winhttp.h>
+#endif
+
+#define WC_ERR_INVALID_CHARS 0x80
+
char *git_win32_get_error_message(DWORD error_code)
{
LPWSTR lpMsgBuf = NULL;
+ HMODULE hModule = NULL;
+ char *utf8_msg = NULL;
+ int utf8_size;
+ DWORD dwFlags =
+ FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_IGNORE_INSERTS;
if (!error_code)
return NULL;
- if (FormatMessageW(
- FORMAT_MESSAGE_ALLOCATE_BUFFER |
- FORMAT_MESSAGE_FROM_SYSTEM |
- FORMAT_MESSAGE_IGNORE_INSERTS,
- NULL, error_code, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
- (LPWSTR)&lpMsgBuf, 0, NULL)) {
- int utf8_size = WideCharToMultiByte(CP_UTF8, 0, lpMsgBuf, -1, NULL, 0, NULL, NULL);
-
- char *lpMsgBuf_utf8 = git__malloc(utf8_size * sizeof(char));
- if (lpMsgBuf_utf8 == NULL) {
- LocalFree(lpMsgBuf);
- return NULL;
+#ifdef GIT_WINHTTP
+ /* Errors raised by WinHTTP are not in the system resource table */
+ if (error_code >= WINHTTP_ERROR_BASE &&
+ error_code <= WINHTTP_ERROR_LAST)
+ hModule = GetModuleHandleW(L"winhttp");
+#endif
+
+ GIT_UNUSED(hModule);
+
+ if (hModule)
+ dwFlags |= FORMAT_MESSAGE_FROM_HMODULE;
+ else
+ dwFlags |= FORMAT_MESSAGE_FROM_SYSTEM;
+
+ if (FormatMessageW(dwFlags, hModule, error_code,
+ MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
+ (LPWSTR)&lpMsgBuf, 0, NULL)) {
+
+ /* Invalid code point check supported on Vista+ only */
+ if (git_has_win32_version(6, 0))
+ dwFlags = WC_ERR_INVALID_CHARS;
+ else
+ dwFlags = 0;
+
+ utf8_size = WideCharToMultiByte(CP_UTF8, dwFlags,
+ lpMsgBuf, -1, NULL, 0, NULL, NULL);
+
+ if (!utf8_size) {
+ assert(0);
+ goto on_error;
}
- if (!WideCharToMultiByte(CP_UTF8, 0, lpMsgBuf, -1, lpMsgBuf_utf8, utf8_size, NULL, NULL)) {
- LocalFree(lpMsgBuf);
- git__free(lpMsgBuf_utf8);
- return NULL;
+
+ utf8_msg = git__malloc(utf8_size);
+
+ if (!utf8_msg)
+ goto on_error;
+
+ if (!WideCharToMultiByte(CP_UTF8, dwFlags,
+ lpMsgBuf, -1, utf8_msg, utf8_size, NULL, NULL)) {
+ git__free(utf8_msg);
+ goto on_error;
}
+on_error:
LocalFree(lpMsgBuf);
- return lpMsgBuf_utf8;
}
- return NULL;
+
+ return utf8_msg;
}
diff --git a/src/win32/version.h b/src/win32/version.h
new file mode 100644
index 0000000..483962b
--- /dev/null
+++ b/src/win32/version.h
@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) the libgit2 contributors. All rights reserved.
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+#ifndef INCLUDE_win32_version_h__
+#define INCLUDE_win32_version_h__
+
+#include <windows.h>
+
+GIT_INLINE(int) git_has_win32_version(int major, int minor)
+{
+ WORD wVersion = LOWORD(GetVersion());
+
+ return LOBYTE(wVersion) > major ||
+ (LOBYTE(wVersion) == major && HIBYTE(wVersion) >= minor);
+}
+
+#endif