mirror of
https://github.com/git/git
synced 2024-08-25 02:35:46 +00:00
![Jeff King](/assets/img/avatar_default.png)
If close_tempfile() encounters an error, then it deletes the tempfile and resets the "struct tempfile". But many code paths ignore the return value and continue to use the tempfile. Instead, we should generally treat this the same as a write() error. Note that in the postimage of some of these cases our error message will be bogus after a failed close because we look at tempfile->filename (either directly or via get_tempfile_path). But after the failed close resets the tempfile object, this is guaranteed to be the empty string. That will be addressed in a future patch (because there are many more cases of the same problem than just these instances). Note also in the hunk in gpg-interface.c that it's fine to call delete_tempfile() in the error path, even if close_tempfile() failed and already deleted the file. The tempfile code is smart enough to know the second deletion is a noop. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
242 lines
6.3 KiB
C
242 lines
6.3 KiB
C
#include "cache.h"
|
|
#include "config.h"
|
|
#include "run-command.h"
|
|
#include "strbuf.h"
|
|
#include "gpg-interface.h"
|
|
#include "sigchain.h"
|
|
#include "tempfile.h"
|
|
|
|
static char *configured_signing_key;
|
|
static const char *gpg_program = "gpg";
|
|
|
|
#define PGP_SIGNATURE "-----BEGIN PGP SIGNATURE-----"
|
|
#define PGP_MESSAGE "-----BEGIN PGP MESSAGE-----"
|
|
|
|
void signature_check_clear(struct signature_check *sigc)
|
|
{
|
|
FREE_AND_NULL(sigc->payload);
|
|
FREE_AND_NULL(sigc->gpg_output);
|
|
FREE_AND_NULL(sigc->gpg_status);
|
|
FREE_AND_NULL(sigc->signer);
|
|
FREE_AND_NULL(sigc->key);
|
|
}
|
|
|
|
static struct {
|
|
char result;
|
|
const char *check;
|
|
} sigcheck_gpg_status[] = {
|
|
{ 'G', "\n[GNUPG:] GOODSIG " },
|
|
{ 'B', "\n[GNUPG:] BADSIG " },
|
|
{ 'U', "\n[GNUPG:] TRUST_NEVER" },
|
|
{ 'U', "\n[GNUPG:] TRUST_UNDEFINED" },
|
|
{ 'E', "\n[GNUPG:] ERRSIG "},
|
|
{ 'X', "\n[GNUPG:] EXPSIG "},
|
|
{ 'Y', "\n[GNUPG:] EXPKEYSIG "},
|
|
{ 'R', "\n[GNUPG:] REVKEYSIG "},
|
|
};
|
|
|
|
void parse_gpg_output(struct signature_check *sigc)
|
|
{
|
|
const char *buf = sigc->gpg_status;
|
|
int i;
|
|
|
|
/* Iterate over all search strings */
|
|
for (i = 0; i < ARRAY_SIZE(sigcheck_gpg_status); i++) {
|
|
const char *found, *next;
|
|
|
|
if (!skip_prefix(buf, sigcheck_gpg_status[i].check + 1, &found)) {
|
|
found = strstr(buf, sigcheck_gpg_status[i].check);
|
|
if (!found)
|
|
continue;
|
|
found += strlen(sigcheck_gpg_status[i].check);
|
|
}
|
|
sigc->result = sigcheck_gpg_status[i].result;
|
|
/* The trust messages are not followed by key/signer information */
|
|
if (sigc->result != 'U') {
|
|
sigc->key = xmemdupz(found, 16);
|
|
/* The ERRSIG message is not followed by signer information */
|
|
if (sigc-> result != 'E') {
|
|
found += 17;
|
|
next = strchrnul(found, '\n');
|
|
sigc->signer = xmemdupz(found, next - found);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
int check_signature(const char *payload, size_t plen, const char *signature,
|
|
size_t slen, struct signature_check *sigc)
|
|
{
|
|
struct strbuf gpg_output = STRBUF_INIT;
|
|
struct strbuf gpg_status = STRBUF_INIT;
|
|
int status;
|
|
|
|
sigc->result = 'N';
|
|
|
|
status = verify_signed_buffer(payload, plen, signature, slen,
|
|
&gpg_output, &gpg_status);
|
|
if (status && !gpg_output.len)
|
|
goto out;
|
|
sigc->payload = xmemdupz(payload, plen);
|
|
sigc->gpg_output = strbuf_detach(&gpg_output, NULL);
|
|
sigc->gpg_status = strbuf_detach(&gpg_status, NULL);
|
|
parse_gpg_output(sigc);
|
|
|
|
out:
|
|
strbuf_release(&gpg_status);
|
|
strbuf_release(&gpg_output);
|
|
|
|
return sigc->result != 'G' && sigc->result != 'U';
|
|
}
|
|
|
|
void print_signature_buffer(const struct signature_check *sigc, unsigned flags)
|
|
{
|
|
const char *output = flags & GPG_VERIFY_RAW ?
|
|
sigc->gpg_status : sigc->gpg_output;
|
|
|
|
if (flags & GPG_VERIFY_VERBOSE && sigc->payload)
|
|
fputs(sigc->payload, stdout);
|
|
|
|
if (output)
|
|
fputs(output, stderr);
|
|
}
|
|
|
|
/*
|
|
* Look at GPG signed content (e.g. a signed tag object), whose
|
|
* payload is followed by a detached signature on it. Return the
|
|
* offset where the embedded detached signature begins, or the end of
|
|
* the data when there is no such signature.
|
|
*/
|
|
size_t parse_signature(const char *buf, unsigned long size)
|
|
{
|
|
char *eol;
|
|
size_t len = 0;
|
|
while (len < size && !starts_with(buf + len, PGP_SIGNATURE) &&
|
|
!starts_with(buf + len, PGP_MESSAGE)) {
|
|
eol = memchr(buf + len, '\n', size - len);
|
|
len += eol ? eol - (buf + len) + 1 : size - len;
|
|
}
|
|
return len;
|
|
}
|
|
|
|
void set_signing_key(const char *key)
|
|
{
|
|
free(configured_signing_key);
|
|
configured_signing_key = xstrdup(key);
|
|
}
|
|
|
|
int git_gpg_config(const char *var, const char *value, void *cb)
|
|
{
|
|
if (!strcmp(var, "user.signingkey")) {
|
|
set_signing_key(value);
|
|
}
|
|
if (!strcmp(var, "gpg.program")) {
|
|
if (!value)
|
|
return config_error_nonbool(var);
|
|
gpg_program = xstrdup(value);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
const char *get_signing_key(void)
|
|
{
|
|
if (configured_signing_key)
|
|
return configured_signing_key;
|
|
return git_committer_info(IDENT_STRICT|IDENT_NO_DATE);
|
|
}
|
|
|
|
/*
|
|
* Create a detached signature for the contents of "buffer" and append
|
|
* it after "signature"; "buffer" and "signature" can be the same
|
|
* strbuf instance, which would cause the detached signature appended
|
|
* at the end.
|
|
*/
|
|
int sign_buffer(struct strbuf *buffer, struct strbuf *signature, const char *signing_key)
|
|
{
|
|
struct child_process gpg = CHILD_PROCESS_INIT;
|
|
int ret;
|
|
size_t i, j, bottom;
|
|
struct strbuf gpg_status = STRBUF_INIT;
|
|
|
|
argv_array_pushl(&gpg.args,
|
|
gpg_program,
|
|
"--status-fd=2",
|
|
"-bsau", signing_key,
|
|
NULL);
|
|
|
|
bottom = signature->len;
|
|
|
|
/*
|
|
* When the username signingkey is bad, program could be terminated
|
|
* because gpg exits without reading and then write gets SIGPIPE.
|
|
*/
|
|
sigchain_push(SIGPIPE, SIG_IGN);
|
|
ret = pipe_command(&gpg, buffer->buf, buffer->len,
|
|
signature, 1024, &gpg_status, 0);
|
|
sigchain_pop(SIGPIPE);
|
|
|
|
ret |= !strstr(gpg_status.buf, "\n[GNUPG:] SIG_CREATED ");
|
|
strbuf_release(&gpg_status);
|
|
if (ret)
|
|
return error(_("gpg failed to sign the data"));
|
|
|
|
/* Strip CR from the line endings, in case we are on Windows. */
|
|
for (i = j = bottom; i < signature->len; i++)
|
|
if (signature->buf[i] != '\r') {
|
|
if (i != j)
|
|
signature->buf[j] = signature->buf[i];
|
|
j++;
|
|
}
|
|
strbuf_setlen(signature, j);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Run "gpg" to see if the payload matches the detached signature.
|
|
* gpg_output, when set, receives the diagnostic output from GPG.
|
|
* gpg_status, when set, receives the status output from GPG.
|
|
*/
|
|
int verify_signed_buffer(const char *payload, size_t payload_size,
|
|
const char *signature, size_t signature_size,
|
|
struct strbuf *gpg_output, struct strbuf *gpg_status)
|
|
{
|
|
struct child_process gpg = CHILD_PROCESS_INIT;
|
|
static struct tempfile temp;
|
|
int fd, ret;
|
|
struct strbuf buf = STRBUF_INIT;
|
|
|
|
fd = mks_tempfile_t(&temp, ".git_vtag_tmpXXXXXX");
|
|
if (fd < 0)
|
|
return error_errno(_("could not create temporary file"));
|
|
if (write_in_full(fd, signature, signature_size) < 0 ||
|
|
close_tempfile(&temp) < 0) {
|
|
error_errno(_("failed writing detached signature to '%s'"),
|
|
temp.filename.buf);
|
|
delete_tempfile(&temp);
|
|
return -1;
|
|
}
|
|
|
|
argv_array_pushl(&gpg.args,
|
|
gpg_program,
|
|
"--status-fd=1",
|
|
"--keyid-format=long",
|
|
"--verify", temp.filename.buf, "-",
|
|
NULL);
|
|
|
|
if (!gpg_status)
|
|
gpg_status = &buf;
|
|
|
|
sigchain_push(SIGPIPE, SIG_IGN);
|
|
ret = pipe_command(&gpg, payload, payload_size,
|
|
gpg_status, 0, gpg_output, 0);
|
|
sigchain_pop(SIGPIPE);
|
|
|
|
delete_tempfile(&temp);
|
|
|
|
ret |= !strstr(gpg_status->buf, "\n[GNUPG:] GOODSIG ");
|
|
strbuf_release(&buf); /* no matter it was used or not */
|
|
|
|
return ret;
|
|
}
|