#include "builtin.h"
+#include "lockfile.h"
#include "pack.h"
#include "refs.h"
#include "pkt-line.h"
#include "version.h"
#include "tag.h"
#include "gpg-interface.h"
+#include "sigchain.h"
static const char receive_pack_usage[] = "git receive-pack <git-dir>";
static int auto_update_server_info;
static int auto_gc = 1;
static int fix_thin = 1;
+static int stateless_rpc;
+static const char *service_dir;
static const char *head_name;
static void *head_name_to_free;
static int sent_capabilities;
static int shallow_update;
static const char *alt_shallow_file;
-static int accept_push_cert = 1;
static struct strbuf push_cert = STRBUF_INIT;
static unsigned char push_cert_sha1[20];
static struct signature_check sigcheck;
+static const char *push_cert_nonce;
+static const char *cert_nonce_seed;
+
+static const char *NONCE_UNSOLICITED = "UNSOLICITED";
+static const char *NONCE_BAD = "BAD";
+static const char *NONCE_MISSING = "MISSING";
+static const char *NONCE_OK = "OK";
+static const char *NONCE_SLOP = "SLOP";
+static const char *nonce_status;
+static long nonce_stamp_slop;
+static unsigned long nonce_stamp_slop_limit;
static enum deny_action parse_deny_action(const char *var, const char *value)
{
return 0;
}
- if (strcmp(var, "receive.acceptpushcert") == 0) {
- accept_push_cert = git_config_bool(var, value);
+ if (strcmp(var, "receive.certnonceseed") == 0)
+ return git_config_string(&cert_nonce_seed, var, value);
+
+ if (strcmp(var, "receive.certnonceslop") == 0) {
+ nonce_stamp_slop_limit = git_config_ulong(var, value);
return 0;
}
"report-status delete-refs side-band-64k quiet");
if (prefer_ofs_delta)
strbuf_addstr(&cap, " ofs-delta");
- if (accept_push_cert)
- strbuf_addstr(&cap, " push-cert");
+ if (push_cert_nonce)
+ strbuf_addf(&cap, " push-cert=%s", push_cert_nonce);
strbuf_addf(&cap, " agent=%s", git_user_agent_sanitized());
packet_write(1, "%s %s%c%s\n",
sha1_to_hex(sha1), path, 0, cap.buf);
return 0;
}
+#define HMAC_BLOCK_SIZE 64
+
+static void hmac_sha1(unsigned char *out,
+ const char *key_in, size_t key_len,
+ const char *text, size_t text_len)
+{
+ unsigned char key[HMAC_BLOCK_SIZE];
+ unsigned char k_ipad[HMAC_BLOCK_SIZE];
+ unsigned char k_opad[HMAC_BLOCK_SIZE];
+ int i;
+ git_SHA_CTX ctx;
+
+ /* RFC 2104 2. (1) */
+ memset(key, '\0', HMAC_BLOCK_SIZE);
+ if (HMAC_BLOCK_SIZE < key_len) {
+ git_SHA1_Init(&ctx);
+ git_SHA1_Update(&ctx, key_in, key_len);
+ git_SHA1_Final(key, &ctx);
+ } else {
+ memcpy(key, key_in, key_len);
+ }
+
+ /* RFC 2104 2. (2) & (5) */
+ for (i = 0; i < sizeof(key); i++) {
+ k_ipad[i] = key[i] ^ 0x36;
+ k_opad[i] = key[i] ^ 0x5c;
+ }
+
+ /* RFC 2104 2. (3) & (4) */
+ git_SHA1_Init(&ctx);
+ git_SHA1_Update(&ctx, k_ipad, sizeof(k_ipad));
+ git_SHA1_Update(&ctx, text, text_len);
+ git_SHA1_Final(out, &ctx);
+
+ /* RFC 2104 2. (6) & (7) */
+ git_SHA1_Init(&ctx);
+ git_SHA1_Update(&ctx, k_opad, sizeof(k_opad));
+ git_SHA1_Update(&ctx, out, 20);
+ git_SHA1_Final(out, &ctx);
+}
+
+static char *prepare_push_cert_nonce(const char *path, unsigned long stamp)
+{
+ struct strbuf buf = STRBUF_INIT;
+ unsigned char sha1[20];
+
+ strbuf_addf(&buf, "%s:%lu", path, stamp);
+ hmac_sha1(sha1, buf.buf, buf.len, cert_nonce_seed, strlen(cert_nonce_seed));;
+ strbuf_release(&buf);
+
+ /* RFC 2104 5. HMAC-SHA1-80 */
+ strbuf_addf(&buf, "%lu-%.*s", stamp, 20, sha1_to_hex(sha1));
+ return strbuf_detach(&buf, NULL);
+}
+
+/*
+ * NEEDSWORK: reuse find_commit_header() from jk/commit-author-parsing
+ * after dropping "_commit" from its name and possibly moving it out
+ * of commit.c
+ */
+static char *find_header(const char *msg, size_t len, const char *key)
+{
+ int key_len = strlen(key);
+ const char *line = msg;
+
+ while (line && line < msg + len) {
+ const char *eol = strchrnul(line, '\n');
+
+ if ((msg + len <= eol) || line == eol)
+ return NULL;
+ if (line + key_len < eol &&
+ !memcmp(line, key, key_len) && line[key_len] == ' ') {
+ int offset = key_len + 1;
+ return xmemdupz(line + offset, (eol - line) - offset);
+ }
+ line = *eol ? eol + 1 : NULL;
+ }
+ return NULL;
+}
+
+static const char *check_nonce(const char *buf, size_t len)
+{
+ char *nonce = find_header(buf, len, "nonce");
+ unsigned long stamp, ostamp;
+ char *bohmac, *expect = NULL;
+ const char *retval = NONCE_BAD;
+
+ if (!nonce) {
+ retval = NONCE_MISSING;
+ goto leave;
+ } else if (!push_cert_nonce) {
+ retval = NONCE_UNSOLICITED;
+ goto leave;
+ } else if (!strcmp(push_cert_nonce, nonce)) {
+ retval = NONCE_OK;
+ goto leave;
+ }
+
+ if (!stateless_rpc) {
+ /* returned nonce MUST match what we gave out earlier */
+ retval = NONCE_BAD;
+ goto leave;
+ }
+
+ /*
+ * In stateless mode, we may be receiving a nonce issued by
+ * another instance of the server that serving the same
+ * repository, and the timestamps may not match, but the
+ * nonce-seed and dir should match, so we can recompute and
+ * report the time slop.
+ *
+ * In addition, when a nonce issued by another instance has
+ * timestamp within receive.certnonceslop seconds, we pretend
+ * as if we issued that nonce when reporting to the hook.
+ */
+
+ /* nonce is concat(<seconds-since-epoch>, "-", <hmac>) */
+ if (*nonce <= '0' || '9' < *nonce) {
+ retval = NONCE_BAD;
+ goto leave;
+ }
+ stamp = strtoul(nonce, &bohmac, 10);
+ if (bohmac == nonce || bohmac[0] != '-') {
+ retval = NONCE_BAD;
+ goto leave;
+ }
+
+ expect = prepare_push_cert_nonce(service_dir, stamp);
+ if (strcmp(expect, nonce)) {
+ /* Not what we would have signed earlier */
+ retval = NONCE_BAD;
+ goto leave;
+ }
+
+ /*
+ * By how many seconds is this nonce stale? Negative value
+ * would mean it was issued by another server with its clock
+ * skewed in the future.
+ */
+ ostamp = strtoul(push_cert_nonce, NULL, 10);
+ nonce_stamp_slop = (long)ostamp - (long)stamp;
+
+ if (nonce_stamp_slop_limit &&
+ abs(nonce_stamp_slop) <= nonce_stamp_slop_limit) {
+ /*
+ * Pretend as if the received nonce (which passes the
+ * HMAC check, so it is not a forged by third-party)
+ * is what we issued.
+ */
+ free((void *)push_cert_nonce);
+ push_cert_nonce = xstrdup(nonce);
+ retval = NONCE_OK;
+ } else {
+ retval = NONCE_SLOP;
+ }
+
+leave:
+ free(nonce);
+ free(expect);
+ return retval;
+}
+
static void prepare_push_cert_sha1(struct child_process *proc)
{
static int already_done;
- struct argv_array env = ARGV_ARRAY_INIT;
if (!push_cert.len)
return;
strbuf_release(&gpg_output);
strbuf_release(&gpg_status);
+ nonce_status = check_nonce(push_cert.buf, bogs);
}
if (!is_null_sha1(push_cert_sha1)) {
- argv_array_pushf(&env, "GIT_PUSH_CERT=%s", sha1_to_hex(push_cert_sha1));
- argv_array_pushf(&env, "GIT_PUSH_CERT_SIGNER=%s",
+ argv_array_pushf(&proc->env_array, "GIT_PUSH_CERT=%s",
+ sha1_to_hex(push_cert_sha1));
+ argv_array_pushf(&proc->env_array, "GIT_PUSH_CERT_SIGNER=%s",
sigcheck.signer ? sigcheck.signer : "");
- argv_array_pushf(&env, "GIT_PUSH_CERT_KEY=%s",
+ argv_array_pushf(&proc->env_array, "GIT_PUSH_CERT_KEY=%s",
sigcheck.key ? sigcheck.key : "");
- argv_array_pushf(&env, "GIT_PUSH_CERT_STATUS=%c", sigcheck.result);
-
- proc->env = env.argv;
+ argv_array_pushf(&proc->env_array, "GIT_PUSH_CERT_STATUS=%c",
+ sigcheck.result);
+ if (push_cert_nonce) {
+ argv_array_pushf(&proc->env_array,
+ "GIT_PUSH_CERT_NONCE=%s",
+ push_cert_nonce);
+ argv_array_pushf(&proc->env_array,
+ "GIT_PUSH_CERT_NONCE_STATUS=%s",
+ nonce_status);
+ if (nonce_status == NONCE_SLOP)
+ argv_array_pushf(&proc->env_array,
+ "GIT_PUSH_CERT_NONCE_SLOP=%ld",
+ nonce_stamp_slop);
+ }
}
}
typedef int (*feed_fn)(void *, const char **, size_t *);
static int run_and_feed_hook(const char *hook_name, feed_fn feed, void *feed_state)
{
- struct child_process proc;
+ struct child_process proc = CHILD_PROCESS_INIT;
struct async muxer;
const char *argv[2];
int code;
argv[1] = NULL;
- memset(&proc, 0, sizeof(proc));
proc.argv = argv;
proc.in = -1;
proc.stdout_to_stderr = 1;
- prepare_push_cert_sha1(&proc);
-
if (use_sideband) {
memset(&muxer, 0, sizeof(muxer));
muxer.proc = copy_to_sideband;
proc.err = muxer.in;
}
+ prepare_push_cert_sha1(&proc);
+
code = start_command(&proc);
if (code) {
if (use_sideband)
return code;
}
+ sigchain_push(SIGPIPE, SIG_IGN);
+
while (1) {
const char *buf;
size_t n;
close(proc.in);
if (use_sideband)
finish_async(&muxer);
+
+ sigchain_pop(SIGPIPE);
+
return finish_command(&proc);
}
static int run_update_hook(struct command *cmd)
{
const char *argv[5];
- struct child_process proc;
+ struct child_process proc = CHILD_PROCESS_INIT;
int code;
argv[0] = find_hook("update");
argv[3] = sha1_to_hex(cmd->new_sha1);
argv[4] = NULL;
- memset(&proc, 0, sizeof(proc));
proc.no_stdin = 1;
proc.stdout_to_stderr = 1;
proc.err = use_sideband ? -1 : 0;
const char *namespaced_name;
unsigned char *old_sha1 = cmd->old_sha1;
unsigned char *new_sha1 = cmd->new_sha1;
- struct ref_lock *lock;
/* only refs/... are allowed */
if (!starts_with(name, "refs/") || check_refname_format(name + 5, 0)) {
return NULL; /* good */
}
else {
+ struct strbuf err = STRBUF_INIT;
+ struct ref_transaction *transaction;
+
if (shallow_update && si->shallow_ref[cmd->index] &&
update_shallow_ref(cmd, si))
return "shallow error";
- lock = lock_any_ref_for_update(namespaced_name, old_sha1,
- 0, NULL);
- if (!lock) {
- rp_error("failed to lock %s", name);
- return "failed to lock";
- }
- if (write_ref_sha1(lock, new_sha1, "push")) {
- return "failed to write"; /* error() already called */
+ transaction = ref_transaction_begin(&err);
+ if (!transaction ||
+ ref_transaction_update(transaction, namespaced_name,
+ new_sha1, old_sha1, 0, 1, "push",
+ &err) ||
+ ref_transaction_commit(transaction, &err)) {
+ ref_transaction_free(transaction);
+
+ rp_error("%s", err.buf);
+ strbuf_release(&err);
+ return "failed to update ref";
}
+
+ ref_transaction_free(transaction);
+ strbuf_release(&err);
return NULL; /* good */
}
}
struct command *cmd;
int argc;
const char **argv;
- struct child_process proc;
+ struct child_process proc = CHILD_PROCESS_INIT;
char *hook;
hook = find_hook("post-update");
}
argv[argc] = NULL;
- memset(&proc, 0, sizeof(proc));
proc.no_stdin = 1;
proc.stdout_to_stderr = 1;
proc.err = use_sideband ? -1 : 0;
int flag;
strbuf_addf(&buf, "%s%s", get_git_namespace(), cmd->ref_name);
- dst_name = resolve_ref_unsafe(buf.buf, sha1, 0, &flag);
+ dst_name = resolve_ref_unsafe(buf.buf, 0, sha1, &flag);
strbuf_release(&buf);
if (!(flag & REF_ISSYMREF))
check_aliased_updates(commands);
free(head_name_to_free);
- head_name = head_name_to_free = resolve_refdup("HEAD", sha1, 0, NULL);
+ head_name = head_name_to_free = resolve_refdup("HEAD", 0, sha1, NULL);
checked_connectivity = 1;
for (cmd = commands; cmd; cmd = cmd->next) {
return &cmd->next;
}
+static void queue_commands_from_cert(struct command **tail,
+ struct strbuf *push_cert)
+{
+ const char *boc, *eoc;
+
+ if (*tail)
+ die("protocol error: got both push certificate and unsigned commands");
+
+ boc = strstr(push_cert->buf, "\n\n");
+ if (!boc)
+ die("malformed push certificate %.*s", 100, push_cert->buf);
+ else
+ boc += 2;
+ eoc = push_cert->buf + parse_signature(push_cert->buf, push_cert->len);
+
+ while (boc < eoc) {
+ const char *eol = memchr(boc, '\n', eoc - boc);
+ tail = queue_command(tail, boc, eol ? eol - boc : eoc - eol);
+ boc = eol ? eol + 1 : eoc;
+ }
+}
+
static struct command *read_head_info(struct sha1_array *shallow)
{
struct command *commands = NULL;
p = queue_command(p, line, linelen);
}
+
+ if (push_cert.len)
+ queue_commands_from_cert(p, &push_cert);
+
return commands;
}
static const char *unpack(int err_fd, struct shallow_info *si)
{
struct pack_header hdr;
- struct argv_array av = ARGV_ARRAY_INIT;
const char *hdr_err;
int status;
char hdr_arg[38];
- struct child_process child;
+ struct child_process child = CHILD_PROCESS_INIT;
int fsck_objects = (receive_fsck_objects >= 0
? receive_fsck_objects
: transfer_fsck_objects >= 0
if (si->nr_ours || si->nr_theirs) {
alt_shallow_file = setup_temporary_shallow(si->shallow);
- argv_array_pushl(&av, "--shallow-file", alt_shallow_file, NULL);
+ argv_array_push(&child.args, "--shallow-file");
+ argv_array_push(&child.args, alt_shallow_file);
}
- memset(&child, 0, sizeof(child));
if (ntohl(hdr.hdr_entries) < unpack_limit) {
- argv_array_pushl(&av, "unpack-objects", hdr_arg, NULL);
+ argv_array_pushl(&child.args, "unpack-objects", hdr_arg, NULL);
if (quiet)
- argv_array_push(&av, "-q");
+ argv_array_push(&child.args, "-q");
if (fsck_objects)
- argv_array_push(&av, "--strict");
- child.argv = av.argv;
+ argv_array_push(&child.args, "--strict");
child.no_stdout = 1;
child.err = err_fd;
child.git_cmd = 1;
if (gethostname(keep_arg + s, sizeof(keep_arg) - s))
strcpy(keep_arg + s, "localhost");
- argv_array_pushl(&av, "index-pack",
+ argv_array_pushl(&child.args, "index-pack",
"--stdin", hdr_arg, keep_arg, NULL);
if (fsck_objects)
- argv_array_push(&av, "--strict");
+ argv_array_push(&child.args, "--strict");
if (fix_thin)
- argv_array_push(&av, "--fix-thin");
- child.argv = av.argv;
+ argv_array_push(&child.args, "--fix-thin");
child.out = -1;
child.err = err_fd;
child.git_cmd = 1;
int cmd_receive_pack(int argc, const char **argv, const char *prefix)
{
int advertise_refs = 0;
- int stateless_rpc = 0;
int i;
- const char *dir = NULL;
struct command *commands;
struct sha1_array shallow = SHA1_ARRAY_INIT;
struct sha1_array ref = SHA1_ARRAY_INIT;
usage(receive_pack_usage);
}
- if (dir)
+ if (service_dir)
usage(receive_pack_usage);
- dir = arg;
+ service_dir = arg;
}
- if (!dir)
+ if (!service_dir)
usage(receive_pack_usage);
setup_path();
- if (!enter_repo(dir, 0))
- die("'%s' does not appear to be a git repository", dir);
+ if (!enter_repo(service_dir, 0))
+ die("'%s' does not appear to be a git repository", service_dir);
git_config(receive_pack_config, NULL);
+ if (cert_nonce_seed)
+ push_cert_nonce = prepare_push_cert_nonce(service_dir, time(NULL));
if (0 <= transfer_unpack_limit)
unpack_limit = transfer_unpack_limit;
packet_flush(1);
sha1_array_clear(&shallow);
sha1_array_clear(&ref);
+ free((void *)push_cert_nonce);
return 0;
}