imap-send: gracefully fail if CRAM-MD5 authentication is requested without OpenSSL
Unlike PLAIN, XOAUTH2 and OAUTHBEARER, CRAM-MD5 authentication is not supported by libcurl and requires OpenSSL. If the user tries to use CRAM-MD5 authentication without OpenSSL, the previous behaviour was to attempt to authenticate and fail with a die(error). Handle this in a better way by first checking if OpenSSL is available and then attempting to authenticate. If OpenSSL is not available, print an error message and exit gracefully. Signed-off-by: Aditya Garg <gargaditya08@live.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Aditya Garg committed
Jun 20, 2025 at 12:10 UTC
b9e766604df2c50b2f721479bb405409db3344d1
1 file changed
+39
-27
imap-send.c
+39
-27
@@ -885,18 +885,6 @@ static char *cram(const char *challenge_64, const char *user, const char *pass)
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return (char *)response_64;
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}
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-#else
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-
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-static char *cram(const char *challenge_64 UNUSED,
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- const char *user UNUSED,
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- const char *pass UNUSED)
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-{
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- die("If you want to use CRAM-MD5 authenticate method, "
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- "you have to build git-imap-send with OpenSSL library.");
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-}
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-
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-#endif
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-
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static int auth_cram_md5(struct imap_store *ctx, const char *prompt)
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{
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int ret;
@@ -915,6 +903,12 @@ static int auth_cram_md5(struct imap_store *ctx, const char *prompt)
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return 0;
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}
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+#else
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+
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+#define auth_cram_md5 NULL
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+
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+#endif
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+
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static void server_fill_credential(struct imap_server_conf *srvc, struct credential *cred)
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{
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if (srvc->user && srvc->pass)
@@ -934,6 +928,38 @@ static void server_fill_credential(struct imap_server_conf *srvc, struct credent
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srvc->pass = xstrdup(cred->password);
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}
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+static int try_auth_method(struct imap_server_conf *srvc,
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+ struct imap_store *ctx,
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+ struct imap *imap,
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+ const char *auth_method,
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+ enum CAPABILITY cap,
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+ int (*fn)(struct imap_store *, const char *))
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+{
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+ struct imap_cmd_cb cb = {0};
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+
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+ if (!CAP(cap)) {
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+ fprintf(stderr, "You specified "
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+ "%s as authentication method, "
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+ "but %s doesn't support it.\n",
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+ auth_method, srvc->host);
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+ return -1;
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+ }
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+ cb.cont = fn;
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+
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+ if (NOT_CONSTANT(!cb.cont)) {
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+ fprintf(stderr, "If you want to use %s authentication mechanism, "
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+ "you have to build git-imap-send with OpenSSL library.",
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+ auth_method);
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+ return -1;
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+ }
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+ if (imap_exec(ctx, &cb, "AUTHENTICATE %s", auth_method) != RESP_OK) {
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+ fprintf(stderr, "IMAP error: AUTHENTICATE %s failed\n",
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+ auth_method);
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+ return -1;
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+ }
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+ return 0;
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+}
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+
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static struct imap_store *imap_open_store(struct imap_server_conf *srvc, const char *folder)
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{
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struct credential cred = CREDENTIAL_INIT;
@@ -1089,23 +1115,9 @@ static struct imap_store *imap_open_store(struct imap_server_conf *srvc, const c
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server_fill_credential(srvc, &cred);
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if (srvc->auth_method) {
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- struct imap_cmd_cb cb;
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-
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if (!strcmp(srvc->auth_method, "CRAM-MD5")) {
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- if (!CAP(AUTH_CRAM_MD5)) {
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- fprintf(stderr, "You specified "
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- "CRAM-MD5 as authentication method, "
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- "but %s doesn't support it.\n", srvc->host);
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- goto bail;
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- }
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- /* CRAM-MD5 */
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-
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- memset(&cb, 0, sizeof(cb));
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- cb.cont = auth_cram_md5;
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- if (imap_exec(ctx, &cb, "AUTHENTICATE CRAM-MD5") != RESP_OK) {
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- fprintf(stderr, "IMAP error: AUTHENTICATE CRAM-MD5 failed\n");
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+ if (try_auth_method(srvc, ctx, imap, "CRAM-MD5", AUTH_CRAM_MD5, auth_cram_md5))
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goto bail;
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- }
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} else {
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fprintf(stderr, "Unknown authentication method:%s\n", srvc->host);
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goto bail;