Subject: [PATCH v5] credential-cache: respect authtype capability

From: "M Hickford via GitGitGadget" <[email-masked]>
Date: Thu, 09 Jan 2025 22:45:20 +0000

From: M Hickford <[email-masked]>

Previously, credential-cache populated authtype regardless whether
"get" request had authtype capability. As documented in
git-credential.txt, authtype "should not be sent unless the appropriate
capability ... is provided".

Add test. Without this change, the test failed because "credential fill"
printed an incomplete credential with only protocol and host attributes
(the unexpected authtype attribute was discarded by credential.c).

Signed-off-by: M Hickford <[email-masked]>
---
    credential-cache: respect request capabilities
    
    CC: [email-masked] CC: [email-masked]
    
    Patch v5 adds details to the commit message

Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-1842%2Fhickford%2Fcache-capability-v5
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-1842/hickford/cache-capability-v5
Pull-Request: https://github.com/gitgitgadget/git/pull/1842

Range-diff vs v4:

 1:  23942f9fa47 ! 1:  db575d9d116 credential-cache: respect request capabilities
     @@ Metadata
      Author: M Hickford <[email-masked]>
      
       ## Commit message ##
     -    credential-cache: respect request capabilities
     +    credential-cache: respect authtype capability
      
     -    Previously, credential-cache populated authtype regardless of request.
     +    Previously, credential-cache populated authtype regardless whether
     +    "get" request had authtype capability. As documented in
     +    git-credential.txt, authtype "should not be sent unless the appropriate
     +    capability ... is provided".
     +
     +    Add test. Without this change, the test failed because "credential fill"
     +    printed an incomplete credential with only protocol and host attributes
     +    (the unexpected authtype attribute was discarded by credential.c).
      
          Signed-off-by: M Hickford <[email-masked]>

 builtin/credential-cache--daemon.c |  4 ++--
 t/lib-credential.sh                | 15 +++++++++++++++
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/builtin/credential-cache--daemon.c b/builtin/credential-cache--daemon.c
index bc22f5c6d24..e707618e743 100644
--- a/builtin/credential-cache--daemon.c
+++ b/builtin/credential-cache--daemon.c
@@ -142,9 +142,9 @@ static void serve_one_client(FILE *in, FILE *out)
 				fprintf(out, "username=%s\n", e->item.username);
 			if (e->item.password)
 				fprintf(out, "password=%s\n", e->item.password);
-			if (credential_has_capability(&c.capa_authtype, CREDENTIAL_OP_HELPER) && e->item.authtype)
+			if (credential_has_capability(&c.capa_authtype, CREDENTIAL_OP_RESPONSE) && e->item.authtype)
 				fprintf(out, "authtype=%s\n", e->item.authtype);
-			if (credential_has_capability(&c.capa_authtype, CREDENTIAL_OP_HELPER) && e->item.credential)
+			if (credential_has_capability(&c.capa_authtype, CREDENTIAL_OP_RESPONSE) && e->item.credential)
 				fprintf(out, "credential=%s\n", e->item.credential);
 			if (e->item.password_expiry_utc != TIME_MAX)
 				fprintf(out, "password_expiry_utc=%"PRItime"\n",
diff --git a/t/lib-credential.sh b/t/lib-credential.sh
index 58b9c740605..cc6bf9aa5f3 100644
--- a/t/lib-credential.sh
+++ b/t/lib-credential.sh
@@ -566,6 +566,21 @@ helper_test_authtype() {
 		EOF
 	'
 
+	test_expect_success "helper ($HELPER) gets authtype and credential only if request has authtype capability" '
+		check fill $HELPER <<-\EOF
+		protocol=https
+		host=git.example.com
+		--
+		protocol=https
+		host=git.example.com
+		username=askpass-username
+		password=askpass-password
+		--
+		askpass: Username for '\''https://git.example.com'\'':
+		askpass: Password for '\''https://[email-masked]'\'':
+		EOF
+	'
+
 	test_expect_success "helper ($HELPER) stores authtype and credential with username" '
 		check approve $HELPER <<-\EOF
 		capability[]=authtype

base-commit: 92999a42db1c5f43f330e4f2bca4026b5b81576f
-- 
gitgitgadget