http-backend: respect CONTENT_LENGTH for receive-pack

Push passes to another commands, as described in
https://public-inbox.org/git/20171129032214.GB32345@sigill.intra.peff.net/

As it gets complicated to correctly track the data length, instead transfer
the data through parent process and cut the pipe as the specified length is
reached. Do it only when CONTENT_LENGTH is set, otherwise pass the input
directly to the forked commands.

Add tests for cases:

* CONTENT_LENGTH is set, script's stdin has more data, with all combinations
  of variations: fetch or push, plain or compressed body, correct or truncated
  input.

* CONTENT_LENGTH is specified to a value which does not fit into ssize_t.

Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Max Kirillov <max@max630.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Max Kirillov 2018-07-27 06:48:59 +03:00 committed by Junio C Hamano
parent c79edf73f4
commit 6c213e863a
4 changed files with 223 additions and 2 deletions

1
help.c
View file

@ -609,6 +609,7 @@ int cmd_version(int argc, const char **argv, const char *prefix)
else
printf("no commit associated with this build\n");
printf("sizeof-long: %d\n", (int)sizeof(long));
printf("sizeof-size_t: %d\n", (int)sizeof(size_t));
/* NEEDSWORK: also save and output GIT-BUILD_OPTIONS? */
}
return 0;

View file

@ -373,6 +373,8 @@ static void inflate_request(const char *prog_name, int out, int buffer_input, ss
unsigned char in_buf[8192];
unsigned char out_buf[8192];
unsigned long cnt = 0;
int req_len_defined = req_len >= 0;
size_t req_remaining_len = req_len;
memset(&stream, 0, sizeof(stream));
git_inflate_init_gzip_only(&stream);
@ -387,8 +389,15 @@ static void inflate_request(const char *prog_name, int out, int buffer_input, ss
n = read_request(0, &full_request, req_len);
stream.next_in = full_request;
} else {
n = xread(0, in_buf, sizeof(in_buf));
ssize_t buffer_len;
if (req_len_defined && req_remaining_len <= sizeof(in_buf))
buffer_len = req_remaining_len;
else
buffer_len = sizeof(in_buf);
n = xread(0, in_buf, buffer_len);
stream.next_in = in_buf;
if (req_len_defined && n > 0)
req_remaining_len -= n;
}
if (n <= 0)
@ -431,6 +440,23 @@ static void copy_request(const char *prog_name, int out, ssize_t req_len)
free(buf);
}
static void pipe_fixed_length(const char *prog_name, int out, size_t req_len)
{
unsigned char buf[8192];
size_t remaining_len = req_len;
while (remaining_len > 0) {
size_t chunk_length = remaining_len > sizeof(buf) ? sizeof(buf) : remaining_len;
ssize_t n = xread(0, buf, chunk_length);
if (n < 0)
die_errno("Reading request failed");
write_to_child(out, buf, n, prog_name);
remaining_len -= n;
}
close(out);
}
static void run_service(const char **argv, int buffer_input)
{
const char *encoding = getenv("HTTP_CONTENT_ENCODING");
@ -457,7 +483,7 @@ static void run_service(const char **argv, int buffer_input)
"GIT_COMMITTER_EMAIL=%s@http.%s", user, host);
cld.argv = argv;
if (buffer_input || gzipped_request)
if (buffer_input || gzipped_request || req_len >= 0)
cld.in = -1;
cld.git_cmd = 1;
if (start_command(&cld))
@ -468,6 +494,8 @@ static void run_service(const char **argv, int buffer_input)
inflate_request(argv[0], cld.in, buffer_input, req_len);
else if (buffer_input)
copy_request(argv[0], cld.in, req_len);
else if (req_len >= 0)
pipe_fixed_length(argv[0], cld.in, req_len);
else
close(0);

View file

@ -0,0 +1,155 @@
#!/bin/sh
test_description='test git-http-backend respects CONTENT_LENGTH'
. ./test-lib.sh
test_lazy_prereq GZIP 'gzip --version'
verify_http_result() {
# some fatal errors still produce status 200
# so check if there is the error message
if grep 'fatal:' act.err
then
return 1
fi
if ! grep "Status" act.out >act
then
printf "Status: 200 OK\r\n" >act
fi
printf "Status: $1\r\n" >exp &&
test_cmp exp act
}
test_http_env() {
handler_type="$1"
request_body="$2"
shift
env \
CONTENT_TYPE="application/x-git-$handler_type-pack-request" \
QUERY_STRING="/repo.git/git-$handler_type-pack" \
PATH_TRANSLATED="$PWD/.git/git-$handler_type-pack" \
GIT_HTTP_EXPORT_ALL=TRUE \
REQUEST_METHOD=POST \
"$TEST_DIRECTORY"/t5562/invoke-with-content-length.pl \
"$request_body" git http-backend >act.out 2>act.err
}
ssize_b100dots() {
# hardcoded ((size_t) SSIZE_MAX) + 1
case "$(build_option sizeof-size_t)" in
8) echo 9223372036854775808;;
4) echo 2147483648;;
*) die "Unexpected ssize_t size: $(build_option sizeof-size_t)";;
esac
}
test_expect_success 'setup' '
export HTTP_CONTENT_ENCODING="identity" &&
git config http.receivepack true &&
test_commit c0 &&
test_commit c1 &&
hash_head=$(git rev-parse HEAD) &&
hash_prev=$(git rev-parse HEAD~1) &&
printf "want %s" "$hash_head" | packetize >fetch_body &&
printf 0000 >>fetch_body &&
printf "have %s" "$hash_prev" | packetize >>fetch_body &&
printf done | packetize >>fetch_body &&
test_copy_bytes 10 <fetch_body >fetch_body.trunc &&
hash_next=$(git commit-tree -p HEAD -m next HEAD^{tree}) &&
printf "%s %s refs/heads/newbranch\\0report-status\\n" "$_z40" "$hash_next" | packetize >push_body &&
printf 0000 >>push_body &&
echo "$hash_next" | git pack-objects --stdout >>push_body &&
test_copy_bytes 10 <push_body >push_body.trunc &&
: >empty_body
'
test_expect_success GZIP 'setup, compression related' '
gzip -c fetch_body >fetch_body.gz &&
test_copy_bytes 10 <fetch_body.gz >fetch_body.gz.trunc &&
gzip -c push_body >push_body.gz &&
test_copy_bytes 10 <push_body.gz >push_body.gz.trunc
'
test_expect_success 'fetch plain' '
test_http_env upload fetch_body &&
verify_http_result "200 OK"
'
test_expect_success 'fetch plain truncated' '
test_http_env upload fetch_body.trunc &&
! verify_http_result "200 OK"
'
test_expect_success 'fetch plain empty' '
test_http_env upload empty_body &&
! verify_http_result "200 OK"
'
test_expect_success GZIP 'fetch gzipped' '
test_env HTTP_CONTENT_ENCODING="gzip" test_http_env upload fetch_body.gz &&
verify_http_result "200 OK"
'
test_expect_success GZIP 'fetch gzipped truncated' '
test_env HTTP_CONTENT_ENCODING="gzip" test_http_env upload fetch_body.gz.trunc &&
! verify_http_result "200 OK"
'
test_expect_success GZIP 'fetch gzipped empty' '
test_env HTTP_CONTENT_ENCODING="gzip" test_http_env upload empty_body &&
! verify_http_result "200 OK"
'
test_expect_success GZIP 'push plain' '
test_when_finished "git branch -D newbranch" &&
test_http_env receive push_body &&
verify_http_result "200 OK" &&
git rev-parse newbranch >act.head &&
echo "$hash_next" >exp.head &&
test_cmp act.head exp.head
'
test_expect_success 'push plain truncated' '
test_http_env receive push_body.trunc &&
! verify_http_result "200 OK"
'
test_expect_success 'push plain empty' '
test_http_env receive empty_body &&
! verify_http_result "200 OK"
'
test_expect_success GZIP 'push gzipped' '
test_when_finished "git branch -D newbranch" &&
test_env HTTP_CONTENT_ENCODING="gzip" test_http_env receive push_body.gz &&
verify_http_result "200 OK" &&
git rev-parse newbranch >act.head &&
echo "$hash_next" >exp.head &&
test_cmp act.head exp.head
'
test_expect_success GZIP 'push gzipped truncated' '
test_env HTTP_CONTENT_ENCODING="gzip" test_http_env receive push_body.gz.trunc &&
! verify_http_result "200 OK"
'
test_expect_success GZIP 'push gzipped empty' '
test_env HTTP_CONTENT_ENCODING="gzip" test_http_env receive empty_body &&
! verify_http_result "200 OK"
'
test_expect_success 'CONTENT_LENGTH overflow ssite_t' '
NOT_FIT_IN_SSIZE=$(ssize_b100dots) &&
env \
CONTENT_TYPE=application/x-git-upload-pack-request \
QUERY_STRING=/repo.git/git-upload-pack \
PATH_TRANSLATED="$PWD"/.git/git-upload-pack \
GIT_HTTP_EXPORT_ALL=TRUE \
REQUEST_METHOD=POST \
CONTENT_LENGTH="$NOT_FIT_IN_SSIZE" \
git http-backend </dev/zero >/dev/null 2>err &&
grep "fatal:.*CONTENT_LENGTH" err
'
test_done

View file

@ -0,0 +1,37 @@
#!/usr/bin/perl
use 5.008;
use strict;
use warnings;
my $body_filename = $ARGV[0];
my @command = @ARGV[1 .. $#ARGV];
# read data
my $body_size = -s $body_filename;
$ENV{"CONTENT_LENGTH"} = $body_size;
open(my $body_fh, "<", $body_filename) or die "Cannot open $body_filename: $!";
my $body_data;
defined read($body_fh, $body_data, $body_size) or die "Cannot read $body_filename: $!";
close($body_fh);
my $exited = 0;
$SIG{"CHLD"} = sub {
$exited = 1;
};
# write data
my $pid = open(my $out, "|-", @command);
{
# disable buffering at $out
my $old_selected = select;
select $out;
$| = 1;
select $old_selected;
}
print $out $body_data or die "Cannot write data: $!";
sleep 60; # is interrupted by SIGCHLD
if (!$exited) {
close($out);
die "Command did not exit after reading whole body";
}