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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-09 13:34:27 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-09 13:34:27 +0000 |
commit | 4dbdc42d9e7c3968ff7f690d00680419c9b8cb0f (patch) | |
tree | 47c1d492e9c956c1cd2b74dbd3b9d8b0db44dc4e /contrib/credential/wincred/git-credential-wincred.c | |
parent | Initial commit. (diff) | |
download | git-4dbdc42d9e7c3968ff7f690d00680419c9b8cb0f.tar.xz git-4dbdc42d9e7c3968ff7f690d00680419c9b8cb0f.zip |
Adding upstream version 1:2.43.0.upstream/1%2.43.0
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'contrib/credential/wincred/git-credential-wincred.c')
-rw-r--r-- | contrib/credential/wincred/git-credential-wincred.c | 318 |
1 files changed, 318 insertions, 0 deletions
diff --git a/contrib/credential/wincred/git-credential-wincred.c b/contrib/credential/wincred/git-credential-wincred.c new file mode 100644 index 0000000..4cd56c4 --- /dev/null +++ b/contrib/credential/wincred/git-credential-wincred.c @@ -0,0 +1,318 @@ +/* + * A git credential helper that interface with Windows' Credential Manager + * + */ +#include <windows.h> +#include <stdio.h> +#include <io.h> +#include <fcntl.h> +#include <wincred.h> + +/* common helpers */ + +#define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0])) + +__attribute__((format (printf, 1, 2))) +static void die(const char *err, ...) +{ + char msg[4096]; + va_list params; + va_start(params, err); + vsnprintf(msg, sizeof(msg), err, params); + fprintf(stderr, "%s\n", msg); + va_end(params); + exit(1); +} + +static void *xmalloc(size_t size) +{ + void *ret = malloc(size); + if (!ret && !size) + ret = malloc(1); + if (!ret) + die("Out of memory"); + return ret; +} + +static WCHAR *wusername, *password, *protocol, *host, *path, target[1024], + *password_expiry_utc; + +static void write_item(const char *what, LPCWSTR wbuf, int wlen) +{ + char *buf; + + if (!wbuf || !wlen) { + printf("%s=\n", what); + return; + } + + int len = WideCharToMultiByte(CP_UTF8, 0, wbuf, wlen, NULL, 0, NULL, + FALSE); + buf = xmalloc(len); + + if (!WideCharToMultiByte(CP_UTF8, 0, wbuf, wlen, buf, len, NULL, FALSE)) + die("WideCharToMultiByte failed!"); + + printf("%s=", what); + fwrite(buf, 1, len, stdout); + putchar('\n'); + free(buf); +} + +/* + * Match an (optional) expected string and a delimiter in the target string, + * consuming the matched text by updating the target pointer. + */ + +static LPCWSTR wcsstr_last(LPCWSTR str, LPCWSTR find) +{ + LPCWSTR res = NULL, pos; + for (pos = wcsstr(str, find); pos; pos = wcsstr(pos + 1, find)) + res = pos; + return res; +} + +static int match_part_with_last(LPCWSTR *ptarget, LPCWSTR want, LPCWSTR delim, int last) +{ + LPCWSTR delim_pos, start = *ptarget; + int len; + + /* find start of delimiter (or end-of-string if delim is empty) */ + if (*delim) + delim_pos = last ? wcsstr_last(start, delim) : wcsstr(start, delim); + else + delim_pos = start + wcslen(start); + + /* + * match text up to delimiter, or end of string (e.g. the '/' after + * host is optional if not followed by a path) + */ + if (delim_pos) + len = delim_pos - start; + else + len = wcslen(start); + + /* update ptarget if we either found a delimiter or need a match */ + if (delim_pos || want) + *ptarget = delim_pos ? delim_pos + wcslen(delim) : start + len; + + return !want || (!wcsncmp(want, start, len) && !want[len]); +} + +static int match_part(LPCWSTR *ptarget, LPCWSTR want, LPCWSTR delim) +{ + return match_part_with_last(ptarget, want, delim, 0); +} + +static int match_part_last(LPCWSTR *ptarget, LPCWSTR want, LPCWSTR delim) +{ + return match_part_with_last(ptarget, want, delim, 1); +} + +static int match_cred_password(const CREDENTIALW *cred) { + int ret; + WCHAR *cred_password = xmalloc(cred->CredentialBlobSize); + wcsncpy_s(cred_password, cred->CredentialBlobSize, + (LPCWSTR)cred->CredentialBlob, + cred->CredentialBlobSize / sizeof(WCHAR)); + ret = !wcscmp(cred_password, password); + free(cred_password); + return ret; +} + +static int match_cred(const CREDENTIALW *cred, int match_password) +{ + LPCWSTR target = cred->TargetName; + if (wusername && wcscmp(wusername, cred->UserName ? cred->UserName : L"")) + return 0; + + return match_part(&target, L"git", L":") && + match_part(&target, protocol, L"://") && + match_part_last(&target, wusername, L"@") && + match_part(&target, host, L"/") && + match_part(&target, path, L"") && + (!match_password || match_cred_password(cred)); +} + +static void get_credential(void) +{ + CREDENTIALW **creds; + DWORD num_creds; + int i; + CREDENTIAL_ATTRIBUTEW *attr; + + if (!CredEnumerateW(L"git:*", 0, &num_creds, &creds)) + return; + + /* search for the first credential that matches username */ + for (i = 0; i < num_creds; ++i) + if (match_cred(creds[i], 0)) { + write_item("username", creds[i]->UserName, + creds[i]->UserName ? wcslen(creds[i]->UserName) : 0); + write_item("password", + (LPCWSTR)creds[i]->CredentialBlob, + creds[i]->CredentialBlobSize / sizeof(WCHAR)); + for (int j = 0; j < creds[i]->AttributeCount; j++) { + attr = creds[i]->Attributes + j; + if (!wcscmp(attr->Keyword, L"git_password_expiry_utc")) { + write_item("password_expiry_utc", (LPCWSTR)attr->Value, + attr->ValueSize / sizeof(WCHAR)); + break; + } + } + break; + } + + CredFree(creds); +} + +static void store_credential(void) +{ + CREDENTIALW cred; + CREDENTIAL_ATTRIBUTEW expiry_attr; + + if (!wusername || !password) + return; + + cred.Flags = 0; + cred.Type = CRED_TYPE_GENERIC; + cred.TargetName = target; + cred.Comment = L"saved by git-credential-wincred"; + cred.CredentialBlobSize = (wcslen(password)) * sizeof(WCHAR); + cred.CredentialBlob = (LPVOID)password; + cred.Persist = CRED_PERSIST_LOCAL_MACHINE; + cred.AttributeCount = 0; + cred.Attributes = NULL; + if (password_expiry_utc != NULL) { + expiry_attr.Keyword = L"git_password_expiry_utc"; + expiry_attr.Value = (LPVOID)password_expiry_utc; + expiry_attr.ValueSize = (wcslen(password_expiry_utc)) * sizeof(WCHAR); + expiry_attr.Flags = 0; + cred.Attributes = &expiry_attr; + cred.AttributeCount = 1; + } + cred.TargetAlias = NULL; + cred.UserName = wusername; + + if (!CredWriteW(&cred, 0)) + die("CredWrite failed"); +} + +static void erase_credential(void) +{ + CREDENTIALW **creds; + DWORD num_creds; + int i; + + if (!CredEnumerateW(L"git:*", 0, &num_creds, &creds)) + return; + + for (i = 0; i < num_creds; ++i) { + if (match_cred(creds[i], password != NULL)) + CredDeleteW(creds[i]->TargetName, creds[i]->Type, 0); + } + + CredFree(creds); +} + +static WCHAR *utf8_to_utf16_dup(const char *str) +{ + int wlen = MultiByteToWideChar(CP_UTF8, 0, str, -1, NULL, 0); + WCHAR *wstr = xmalloc(sizeof(WCHAR) * wlen); + MultiByteToWideChar(CP_UTF8, 0, str, -1, wstr, wlen); + return wstr; +} + +#define KB (1024) + +static void read_credential(void) +{ + size_t alloc = 100 * KB; + char *buf = calloc(alloc, sizeof(*buf)); + + while (fgets(buf, alloc, stdin)) { + char *v; + size_t len = strlen(buf); + int ends_in_newline = 0; + /* strip trailing CR / LF */ + if (len && buf[len - 1] == '\n') { + buf[--len] = 0; + ends_in_newline = 1; + } + if (len && buf[len - 1] == '\r') + buf[--len] = 0; + + if (!ends_in_newline) + die("bad input: %s", buf); + + if (!*buf) + break; + + v = strchr(buf, '='); + if (!v) + die("bad input: %s", buf); + *v++ = '\0'; + + if (!strcmp(buf, "protocol")) + protocol = utf8_to_utf16_dup(v); + else if (!strcmp(buf, "host")) + host = utf8_to_utf16_dup(v); + else if (!strcmp(buf, "path")) + path = utf8_to_utf16_dup(v); + else if (!strcmp(buf, "username")) { + wusername = utf8_to_utf16_dup(v); + } else if (!strcmp(buf, "password")) + password = utf8_to_utf16_dup(v); + else if (!strcmp(buf, "password_expiry_utc")) + password_expiry_utc = utf8_to_utf16_dup(v); + /* + * Ignore other lines; we don't know what they mean, but + * this future-proofs us when later versions of git do + * learn new lines, and the helpers are updated to match. + */ + } + + free(buf); +} + +int main(int argc, char *argv[]) +{ + const char *usage = + "usage: git credential-wincred <get|store|erase>\n"; + + if (!argv[1]) + die("%s", usage); + + /* git use binary pipes to avoid CRLF-issues */ + _setmode(_fileno(stdin), _O_BINARY); + _setmode(_fileno(stdout), _O_BINARY); + + read_credential(); + + if (!protocol || !(host || path)) + return 0; + + /* prepare 'target', the unique key for the credential */ + wcscpy(target, L"git:"); + wcsncat(target, protocol, ARRAY_SIZE(target)); + wcsncat(target, L"://", ARRAY_SIZE(target)); + if (wusername) { + wcsncat(target, wusername, ARRAY_SIZE(target)); + wcsncat(target, L"@", ARRAY_SIZE(target)); + } + if (host) + wcsncat(target, host, ARRAY_SIZE(target)); + if (path) { + wcsncat(target, L"/", ARRAY_SIZE(target)); + wcsncat(target, path, ARRAY_SIZE(target)); + } + + if (!strcmp(argv[1], "get")) + get_credential(); + else if (!strcmp(argv[1], "store")) + store_credential(); + else if (!strcmp(argv[1], "erase")) + erase_credential(); + /* otherwise, ignore unknown action */ + return 0; +} |