From e44aca614596d49ca802f1602eaf9a4850c3c07d Mon Sep 17 00:00:00 2001 From: Pablo Sabater Date: Fri, 24 Jul 2026 12:54:20 +0200 Subject: [PATCH] protocol-caps: check object existence regardless of the attributes requested Currently, send_info() only checks for existence when the attribute 'size' is also requested. Requesting a bare OID, without attributes only echoes back the OID. Extract the existence check to be done regardless of the number of attributes requested. While at it, introduce a wrapper called get_object_info() similar to odb_read_object_info() that returns OBJ_BAD on fail and adds OBJECT_INFO_SKIP_FETCH_OBJECT and OBJECT_INFO_QUICK flags. OBJECT_INFO_SKIP_FETCH_OBJECT is so a server with a partial clone doesn't trigger fetching objects when it gets an object-info request with an OID that is not available locally. A server should only report what it has locally. Tighten the condition used to determine whether an object is recognized. get_object_info() returns OBJ_BAD for unknown objects, but OBJ_NONE (0) can also mean "not found". Change the check from '< 0' to '<= OBJ_NONE' to cover both as unrecognized. With this patch, a bare OID has two possible responses: 1. Recognized OID: the server answers with "" 2. Unrecognized OID: the server answers with " SP" Update the object-info section in 'gitprotocol-v2.adoc': - Require full obj-oid explicitly. - Fix parentheses. - Define obj-size explicitly. - Make obj-size optional in obj-info and document the behavior for unrecognized object IDs. - Describe the attr header as zero or more pkt-lines, one per attribute, matching what the server implements. A request with no attributes gets no header. Signed-off-by: Pablo Sabater Signed-off-by: Junio C Hamano --- Documentation/gitprotocol-v2.adoc | 21 +++++++---- protocol-caps.c | 47 +++++++++++++++++++---- t/t5701-git-serve.sh | 63 +++++++++++++++++++++++++++++++ 3 files changed, 116 insertions(+), 15 deletions(-) diff --git a/Documentation/gitprotocol-v2.adoc b/Documentation/gitprotocol-v2.adoc index 2beb70595f..7bf62014c3 100644 --- a/Documentation/gitprotocol-v2.adoc +++ b/Documentation/gitprotocol-v2.adoc @@ -568,21 +568,26 @@ An `object-info` request takes the following arguments: oid Indicates to the server an object which the client wants to obtain - information for. + information for. They must be full OIDs. -The response of `object-info` is a list of the requested object ids -and associated requested information, each separated by a single space. +The response of `object-info` consists of one pkt-line per requested attribute, +echoing the attributes the server will report, followed by one pkt-line per +requested object id with its information, each field separated by a single +space. output = info flush-pkt - info = PKT-LINE(attrs) LF) - *PKT-LINE(obj-info LF) - - attrs = attr | attrs SP attrs + info = *PKT-LINE(attr LF) + *PKT-LINE(obj-info LF) attr = "size" - obj-info = obj-id SP obj-size + obj-size = 1*DIGIT + + obj-info = obj-id [SP [obj-size]] + +If the server does not recognize the OID, the response will be ` SP` +regardless of the number of attributes requested. bundle-uri ~~~~~~~~~~ diff --git a/protocol-caps.c b/protocol-caps.c index 8858ea4489..02261be14d 100644 --- a/protocol-caps.c +++ b/protocol-caps.c @@ -30,6 +30,32 @@ static int parse_oid(const char *line, struct string_list *oid_str_list) return 1; } +/* + * odb_read_object_info_extended() wrapper. Similar to odb_read_object_info() + * but uses the flags: + * + * - OBJECT_INFO_SKIP_FETCH_OBJECT so a server won't fetch an object when a + * object-info request asks for an OID that it doesn't have. + * + * - OBJECT_INFO_QUICK to avoid re-scanning packs when the object is not found. + */ +static enum object_type get_object_info(struct object_database *odb, + const struct object_id *oid, + size_t *sizep) +{ + enum object_type type; + struct object_info oi = OBJECT_INFO_INIT; + + oi.typep = &type; + oi.sizep = sizep; + if (odb_read_object_info_extended(odb, oid, &oi, + OBJECT_INFO_LOOKUP_REPLACE | + OBJECT_INFO_SKIP_FETCH_OBJECT | + OBJECT_INFO_QUICK) < 0) + return OBJ_BAD; + return type; +} + /* * Validates and send requested info back to the client. Any errors detected * are returned as they are detected. @@ -62,15 +88,22 @@ static void send_info(struct repository *r, struct packet_writer *writer, strbuf_addstr(&send_buffer, oid_str); - if (info->size) { - if (odb_read_object_info(r->objects, &oid, &object_size) < 0) { - strbuf_addstr(&send_buffer, " "); - } else { - strbuf_addf(&send_buffer, " %"PRIuMAX, - (uintmax_t)object_size); - } + /* + * Check the existence of the object first. + * If an object is not recognized by the server append SP to + * the response. + */ + if (get_object_info(r->objects, &oid, &object_size) <= OBJ_NONE) { + strbuf_addstr(&send_buffer, " "); + goto write; } + if (info->size) { + strbuf_addf(&send_buffer, " %"PRIuMAX, + (uintmax_t)object_size); + } + +write: packet_writer_write(writer, "%s", send_buffer.buf); strbuf_reset(&send_buffer); } diff --git a/t/t5701-git-serve.sh b/t/t5701-git-serve.sh index d4c28bae39..cacff4456c 100755 --- a/t/t5701-git-serve.sh +++ b/t/t5701-git-serve.sh @@ -7,6 +7,8 @@ export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME . ./test-lib.sh +unknown_oid=$(printf "test" | git hash-object --stdin) + test_expect_success 'setup to generate files with expected content' ' printf "agent=git/%s" "$(git version | cut -d" " -f3)" >agent_capability && @@ -364,6 +366,67 @@ test_expect_success 'basics of object-info' ' test_cmp expect actual ' +test_expect_success 'bare OID request' ' + test_config transfer.advertiseObjectInfo true && + + test-tool pkt-line pack >in <<-EOF && + command=object-info + object-format=$(test_oid algo) + 0001 + oid $(git rev-parse two:two.t) + 0000 + EOF + + cat >expect <<-EOF && + $(git rev-parse two:two.t) + 0000 + EOF + + test-tool serve-v2 --stateless-rpc out && + test-tool pkt-line unpack actual && + test_cmp expect actual +' + +test_expect_success 'object-info with bare unrecognized OID' ' + test_config transfer.advertiseObjectInfo true && + + test-tool pkt-line pack >in <<-EOF && + command=object-info + object-format=$(test_oid algo) + 0001 + oid $unknown_oid + 0000 + EOF + + printf "%s \n" "$unknown_oid" >expect && + printf "0000\n" >>expect && + + test-tool serve-v2 --stateless-rpc out && + test-tool pkt-line unpack actual && + test_cmp expect actual +' + +test_expect_success 'object-info with size for unrecognized OID' ' + test_config transfer.advertiseObjectInfo true && + + test-tool pkt-line pack >in <<-EOF && + command=object-info + object-format=$(test_oid algo) + 0001 + size + oid $unknown_oid + 0000 + EOF + + printf "size\n" >expect && + printf "%s \n" "$unknown_oid" >>expect && + printf "0000\n" >>expect && + + test-tool serve-v2 --stateless-rpc out && + test-tool pkt-line unpack actual && + test_cmp expect actual +' + test_expect_success 'test capability advertisement with uploadpack.advertiseBundleURIs' ' test_config uploadpack.advertiseBundleURIs true &&