@matheusbsbs / matheus-bagliano / commits / f061959efd

credential/wincred: store oauth_refresh_token

a5c7656 (credential: new attribute oauth_refresh_token) introduced a new confidential credential attribute and added support to credential-cache. Later 0ce02e2f (credential/libsecret: store new attributes, 2023-06-16) added support in credential-libsecret. To add support in credential-wincred, we encode the new attribute in the CredentialBlob, separated by newline: hunter2 oauth_refresh_token=xyzzy This is extensible and backwards compatible. The credential protocol already assumes that attribute values do not contain newlines. This fixes test "helper (wincred) gets oauth_refresh_token" when t0303-credential-external.sh is run with GIT_TEST_CREDENTIAL_HELPER=wincred. This test was added in a5c76569e7 (credential: new attribute oauth_refresh_token, 2023-04-21). Alternatives considered: store oauth_refresh_token in a wincred attribute. This would be insecure because wincred assumes attribute values to be non-confidential. Signed-off-by: M Hickford <mirth.hickford@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

M Hickford committed Jan 28, 2024 at 21:25 UTC f061959efd6ff16bb26d8b442707a25dd49085ee
1 file changed +40 -6
contrib/credential/wincred/git-credential-wincred.c
+40 -6
@@ -35,7 +35,7 @@ static void *xmalloc(size_t size)
35 }
36
37 static WCHAR *wusername, *password, *protocol, *host, *path, target[1024],
38 - *password_expiry_utc;
38 + *password_expiry_utc, *oauth_refresh_token;
39
40 static void write_item(const char *what, LPCWSTR wbuf, int wlen)
41 {
@@ -128,6 +128,11 @@ static void get_credential(void)
128 DWORD num_creds;
129 int i;
130 CREDENTIAL_ATTRIBUTEW *attr;
131 + WCHAR *secret;
132 + WCHAR *line;
133 + WCHAR *remaining_lines;
134 + WCHAR *part;
135 + WCHAR *remaining_parts;
136
137 if (!CredEnumerateW(L"git:*", 0, &num_creds, &creds))
138 return;
@@ -137,9 +142,24 @@ static void get_credential(void)
142 if (match_cred(creds[i])) {
143 write_item("username", creds[i]->UserName,
144 creds[i]->UserName ? wcslen(creds[i]->UserName) : 0);
140 - write_item("password",
141 - (LPCWSTR)creds[i]->CredentialBlob,
142 - creds[i]->CredentialBlobSize / sizeof(WCHAR));
145 + if (creds[i]->CredentialBlobSize > 0) {
146 + secret = xmalloc(creds[i]->CredentialBlobSize);
147 + wcsncpy_s(secret, creds[i]->CredentialBlobSize, (LPCWSTR)creds[i]->CredentialBlob, creds[i]->CredentialBlobSize / sizeof(WCHAR));
148 + line = wcstok_s(secret, L"\r\n", &remaining_lines);
149 + write_item("password", line, line ? wcslen(line) : 0);
150 + while(line != NULL) {
151 + part = wcstok_s(line, L"=", &remaining_parts);
152 + if (!wcscmp(part, L"oauth_refresh_token")) {
153 + write_item("oauth_refresh_token", remaining_parts, remaining_parts ? wcslen(remaining_parts) : 0);
154 + }
155 + line = wcstok_s(NULL, L"\r\n", &remaining_lines);
156 + }
157 + free(secret);
158 + } else {
159 + write_item("password",
160 + (LPCWSTR)creds[i]->CredentialBlob,
161 + creds[i]->CredentialBlobSize / sizeof(WCHAR));
162 + }
163 for (int j = 0; j < creds[i]->AttributeCount; j++) {
164 attr = creds[i]->Attributes + j;
165 if (!wcscmp(attr->Keyword, L"git_password_expiry_utc")) {
@@ -158,16 +178,26 @@ static void store_credential(void)
178 {
179 CREDENTIALW cred;
180 CREDENTIAL_ATTRIBUTEW expiry_attr;
181 + WCHAR *secret;
182 + int wlen;
183
184 if (!wusername || !password)
185 return;
186
187 + if (oauth_refresh_token) {
188 + wlen = _scwprintf(L"%s\r\noauth_refresh_token=%s", password, oauth_refresh_token);
189 + secret = xmalloc(sizeof(WCHAR) * wlen);
190 + _snwprintf_s(secret, sizeof(WCHAR) * wlen, wlen, L"%s\r\noauth_refresh_token=%s", password, oauth_refresh_token);
191 + } else {
192 + secret = _wcsdup(password);
193 + }
194 +
195 cred.Flags = 0;
196 cred.Type = CRED_TYPE_GENERIC;
197 cred.TargetName = target;
198 cred.Comment = L"saved by git-credential-wincred";
169 - cred.CredentialBlobSize = (wcslen(password)) * sizeof(WCHAR);
170 - cred.CredentialBlob = (LPVOID)password;
199 + cred.CredentialBlobSize = wcslen(secret) * sizeof(WCHAR);
200 + cred.CredentialBlob = (LPVOID)_wcsdup(secret);
201 cred.Persist = CRED_PERSIST_LOCAL_MACHINE;
202 cred.AttributeCount = 0;
203 cred.Attributes = NULL;
@@ -182,6 +212,8 @@ static void store_credential(void)
212 cred.TargetAlias = NULL;
213 cred.UserName = wusername;
214
215 + free(secret);
216 +
217 if (!CredWriteW(&cred, 0))
218 die("CredWrite failed");
219 }
@@ -253,6 +285,8 @@ static void read_credential(void)
285 password = utf8_to_utf16_dup(v);
286 else if (!strcmp(buf, "password_expiry_utc"))
287 password_expiry_utc = utf8_to_utf16_dup(v);
288 + else if (!strcmp(buf, "oauth_refresh_token"))
289 + oauth_refresh_token = utf8_to_utf16_dup(v);
290 /*
291 * Ignore other lines; we don't know what they mean, but
292 * this future-proofs us when later versions of git do