1 files changed, 194 insertions, 104 deletions

diff --git a/gpg-interface.c b/gpg-interface.c
index 68b0c814f7..db17d65f8a 100644
--- a/gpg-interface.c
+++ b/gpg-interface.c
@@ -1,27 +1,78 @@
 #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";
+struct gpg_format {
+	const char *name;
+	const char *program;
+	const char **verify_args;
+	const char **sigs;
+};
+
+static const char *openpgp_verify_args[] = {
+	"--keyid-format=long",
+	NULL
+};
+static const char *openpgp_sigs[] = {
+	"-----BEGIN PGP SIGNATURE-----",
+	"-----BEGIN PGP MESSAGE-----",
+	NULL
+};
+
+static const char *x509_verify_args[] = {
+	NULL
+};
+static const char *x509_sigs[] = {
+	"-----BEGIN SIGNED MESSAGE-----",
+	NULL
+};
+
+static struct gpg_format gpg_format[] = {
+	{ .name = "openpgp", .program = "gpg",
+	  .verify_args = openpgp_verify_args,
+	  .sigs = openpgp_sigs
+	},
+	{ .name = "x509", .program = "gpgsm",
+	  .verify_args = x509_verify_args,
+	  .sigs = x509_sigs
+	},
+};
+
+static struct gpg_format *use_format = &gpg_format[0];
+
+static struct gpg_format *get_format_by_name(const char *str)
+{
+	int i;
 
-#define PGP_SIGNATURE "-----BEGIN PGP SIGNATURE-----"
-#define PGP_MESSAGE "-----BEGIN PGP MESSAGE-----"
+	for (i = 0; i < ARRAY_SIZE(gpg_format); i++)
+		if (!strcmp(gpg_format[i].name, str))
+			return gpg_format + i;
+	return NULL;
+}
+
+static struct gpg_format *get_format_by_sig(const char *sig)
+{
+	int i, j;
+
+	for (i = 0; i < ARRAY_SIZE(gpg_format); i++)
+		for (j = 0; gpg_format[i].sigs[j]; j++)
+			if (starts_with(sig, gpg_format[i].sigs[j]))
+				return gpg_format + i;
+	return NULL;
+}
 
 void signature_check_clear(struct signature_check *sigc)
 {
-	free(sigc->payload);
-	free(sigc->gpg_output);
-	free(sigc->gpg_status);
-	free(sigc->signer);
-	free(sigc->key);
-	sigc->payload = NULL;
-	sigc->gpg_output = NULL;
-	sigc->gpg_status = NULL;
-	sigc->signer = NULL;
-	sigc->key = NULL;
+	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 {
@@ -32,9 +83,13 @@ static struct {
 	{ '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)
+static void parse_gpg_output(struct signature_check *sigc)
 {
 	const char *buf = sigc->gpg_status;
 	int i;
@@ -52,30 +107,70 @@ void parse_gpg_output(struct signature_check *sigc)
 		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);
-			found += 17;
-			next = strchrnul(found, '\n');
-			sigc->signer = xmemdupz(found, next - found);
+			next = strchrnul(found, ' ');
+			sigc->key = xmemdupz(found, next - found);
+			/* The ERRSIG message is not followed by signer information */
+			if (*next && sigc-> result != 'E') {
+				found = next + 1;
+				next = strchrnul(found, '\n');
+				sigc->signer = xmemdupz(found, next - found);
+			}
 		}
 	}
 }
 
-/*
- * 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)
+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);
+	status |= sigc->result != 'G' && sigc->result != 'U';
+
+ out:
+	strbuf_release(&gpg_status);
+	strbuf_release(&gpg_output);
+
+	return !!status;
+}
+
+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);
+}
+
+size_t parse_signature(const char *buf, size_t size)
 {
-	char *eol;
 	size_t len = 0;
-	while (len < size && !starts_with(buf + len, PGP_SIGNATURE) &&
-			!starts_with(buf + len, PGP_MESSAGE)) {
+	size_t match = size;
+	while (len < size) {
+		const char *eol;
+
+		if (get_format_by_sig(buf + len))
+			match = len;
+
 		eol = memchr(buf + len, '\n', size - len);
 		len += eol ? eol - (buf + len) + 1 : size - len;
 	}
-	return len;
+	return match;
 }
 
 void set_signing_key(const char *key)
@@ -86,14 +181,38 @@ void set_signing_key(const char *key)
 
 int git_gpg_config(const char *var, const char *value, void *cb)
 {
+	struct gpg_format *fmt = NULL;
+	char *fmtname = NULL;
+
 	if (!strcmp(var, "user.signingkey")) {
+		if (!value)
+			return config_error_nonbool(var);
 		set_signing_key(value);
+		return 0;
 	}
-	if (!strcmp(var, "gpg.program")) {
+
+	if (!strcmp(var, "gpg.format")) {
 		if (!value)
 			return config_error_nonbool(var);
-		gpg_program = xstrdup(value);
+		fmt = get_format_by_name(value);
+		if (!fmt)
+			return error("unsupported value for %s: %s",
+				     var, value);
+		use_format = fmt;
+		return 0;
+	}
+
+	if (!strcmp(var, "gpg.program") || !strcmp(var, "gpg.openpgp.program"))
+		fmtname = "openpgp";
+
+	if (!strcmp(var, "gpg.x509.program"))
+		fmtname = "x509";
+
+	if (fmtname) {
+		fmt = get_format_by_name(fmtname);
+		return git_config_string(&fmt->program, var, value);
 	}
+
 	return 0;
 }
 
@@ -104,51 +223,33 @@ const char *get_signing_key(void)
 	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;
-	const char *args[4];
-	ssize_t len;
+	int ret;
 	size_t i, j, bottom;
+	struct strbuf gpg_status = STRBUF_INIT;
 
-	gpg.argv = args;
-	gpg.in = -1;
-	gpg.out = -1;
-	args[0] = gpg_program;
-	args[1] = "-bsau";
-	args[2] = signing_key;
-	args[3] = NULL;
+	argv_array_pushl(&gpg.args,
+			 use_format->program,
+			 "--status-fd=2",
+			 "-bsau", signing_key,
+			 NULL);
 
-	if (start_command(&gpg))
-		return error(_("could not run gpg."));
+	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);
-
-	if (write_in_full(gpg.in, buffer->buf, buffer->len) != buffer->len) {
-		close(gpg.in);
-		close(gpg.out);
-		finish_command(&gpg);
-		return error(_("gpg did not accept the data"));
-	}
-	close(gpg.in);
-
-	bottom = signature->len;
-	len = strbuf_read(signature, gpg.out, 1024);
-	close(gpg.out);
-
+	ret = pipe_command(&gpg, buffer->buf, buffer->len,
+			   signature, 1024, &gpg_status, 0);
 	sigchain_pop(SIGPIPE);
 
-	if (finish_command(&gpg) || !len || len < 0)
+	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. */
@@ -163,60 +264,49 @@ int sign_buffer(struct strbuf *buffer, struct strbuf *signature, const char *sig
 	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;
-	const char *args_gpg[] = {NULL, "--status-fd=1", "--verify", "FILE", "-", NULL};
-	char path[PATH_MAX];
-	int fd, ret;
+	struct gpg_format *fmt;
+	struct tempfile *temp;
+	int ret;
 	struct strbuf buf = STRBUF_INIT;
-	struct strbuf *pbuf = &buf;
-
-	args_gpg[0] = gpg_program;
-	fd = git_mkstemp(path, PATH_MAX, ".git_vtag_tmpXXXXXX");
-	if (fd < 0)
-		return error(_("could not create temporary file '%s': %s"),
-			     path, strerror(errno));
-	if (write_in_full(fd, signature, signature_size) < 0)
-		return error(_("failed writing detached signature to '%s': %s"),
-			     path, strerror(errno));
-	close(fd);
-
-	gpg.argv = args_gpg;
-	gpg.in = -1;
-	gpg.out = -1;
-	if (gpg_output)
-		gpg.err = -1;
-	args_gpg[3] = path;
-	if (start_command(&gpg)) {
-		unlink(path);
-		return error(_("could not run gpg."));
+
+	temp = mks_tempfile_t(".git_vtag_tmpXXXXXX");
+	if (!temp)
+		return error_errno(_("could not create temporary file"));
+	if (write_in_full(temp->fd, signature, signature_size) < 0 ||
+	    close_tempfile_gently(temp) < 0) {
+		error_errno(_("failed writing detached signature to '%s'"),
+			    temp->filename.buf);
+		delete_tempfile(&temp);
+		return -1;
 	}
 
-	write_in_full(gpg.in, payload, payload_size);
-	close(gpg.in);
+	fmt = get_format_by_sig(signature);
+	if (!fmt)
+		BUG("bad signature '%s'", signature);
 
-	if (gpg_output) {
-		strbuf_read(gpg_output, gpg.err, 0);
-		close(gpg.err);
-	}
-	if (gpg_status)
-		pbuf = gpg_status;
-	strbuf_read(pbuf, gpg.out, 0);
-	close(gpg.out);
+	argv_array_push(&gpg.args, fmt->program);
+	argv_array_pushv(&gpg.args, fmt->verify_args);
+	argv_array_pushl(&gpg.args,
+			 "--status-fd=1",
+			 "--verify", temp->filename.buf, "-",
+			 NULL);
 
-	ret = finish_command(&gpg);
+	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);
 
-	unlink_or_warn(path);
+	delete_tempfile(&temp);
 
-	ret |= !strstr(pbuf->buf, "\n[GNUPG:] GOODSIG ");
+	ret |= !strstr(gpg_status->buf, "\n[GNUPG:] GOODSIG ");
 	strbuf_release(&buf); /* no matter it was used or not */
 
 	return ret;