Implement openpgp.cert.d based keystore

This does implement the layout on the file system and the write lock of
the openpgp.cert.d proposal according to
https://www.ietf.org/archive/id/draft-nwjw-openpgp-cert-d-00.html
but not the Trust root, Petname mapping or Trusted introducers.

Resolves:  #3341

lib/keystore.cc

@@ -3,6 +3,7 @@
 #include <string>
 
 #include <fcntl.h>
+#include <unistd.h>
 
 #include <rpm/header.h>
 #include <rpm/rpmbase64.h>
@@ -148,6 +149,94 @@ rpmRC keystore_fs::import_key(rpmtxn txn, rpmPubkey key, int replace, rpmFlags f
     return rc;
 }
 
+/*****************************************************************************/
+
+static rpmRC acquire_write_lock(rpmtxn txn)
+{
+    char * keyringpath = rpmGenPath(rpmtxnRootDir(txn), "%{_keyringpath}/", NULL);
+    char * lockpath = rpmGenPath(rpmtxnRootDir(txn), "%{_keyringpath}/", "writelock");
+    FILE* fp = NULL;
+    rpmRC rc = RPMRC_FAIL;
+
+    if (rpmMkdirs(NULL, keyringpath)) {
+	rpmlog(RPMLOG_ERR, _("failed to create keyring directory %s: %s\n"),
+	       keyringpath, strerror(errno));
+	goto exit;
+    }
+
+    fp = std::fopen(lockpath, "wx");
+
+    if (!fp) {
+	rpmlog(RPMLOG_ERR, _("Can't acquire writelock for keyring at %s\n"), keyringpath);
+    } else {
+	rc = RPMRC_OK;
+	std::fclose(fp);
+    }
+
+ exit:
+    free(keyringpath);
+    free(lockpath);
+    return rc;
+}
+
+static void free_write_lock(rpmtxn txn)
+{
+    char * path = rpmGenPath(rpmtxnRootDir(txn), "%{_keyringpath}/", "writelock");
+    unlink(path);
+    free(path);
+}
+
+rpmRC keystore_openpgp_cert_d::load_keys(rpmtxn txn, rpmKeyring keyring)
+{
+    return load_keys_from_glob(txn, keyring, "%{_keyringpath}/*/*");
+}
+
+rpmRC keystore_openpgp_cert_d::delete_key(rpmtxn txn, rpmPubkey key)
+{
+    rpmRC rc = RPMRC_NOTFOUND;
+
+    if (acquire_write_lock(txn) != RPMRC_OK)
+	return RPMRC_FAIL;
+
+    string fp = rpmPubkeyFingerprintAsHex(key);
+    string dir = fp.substr(0, 2);
+    string filename = fp.substr(2);
+    char * filepath = rpmGetPath(rpmtxnRootDir(txn), "%{_keyringpath}/", dir.c_str(), "/", filename.c_str(), NULL);
+    char * dirpath = rpmGetPath(rpmtxnRootDir(txn), "%{_keyringpath}/", dir.c_str(), NULL);
+
+    if (!access(filepath, F_OK))
+	rc = unlink(filepath) ? RPMRC_FAIL : RPMRC_OK;
+    /* delete directory if empty */
+    rmdir(dirpath);
+
+    free(filepath);
+    free(dirpath);
+    free_write_lock(txn);
+    return rc;
+}
+
+rpmRC keystore_openpgp_cert_d::import_key(rpmtxn txn, rpmPubkey key, int replace, rpmFlags flags)
+{
+    rpmRC rc = RPMRC_NOTFOUND;
+
+    if ((rc = acquire_write_lock(txn)) == RPMRC_OK) {
+	string fp = rpmPubkeyFingerprintAsHex(key);
+	string dir = fp.substr(0, 2);
+	string filename = fp.substr(2);
+	char *dirpath = rpmGetPath(rpmtxnRootDir(txn), "%{_keyringpath}/", dir.c_str(), NULL);
+	string dirstr = dirpath;
+
+	rc = write_key_to_disk(key, dirstr, filename, replace, flags);
+
+	free_write_lock(txn);
+	free(dirpath);
+    }
+
+    return rc;
+}
+
+/*****************************************************************************/
+
 rpmRC keystore_rpmdb::load_keys(rpmtxn txn, rpmKeyring keyring)
 {
     Header h;

lib/keystore.hh

@@ -37,6 +37,13 @@ private:
     rpmRC delete_key(rpmtxn txn, const std::string & keyid, unsigned int newinstance = 0);
 };
 
+class keystore_openpgp_cert_d : public keystore {
+public:
+    virtual rpmRC load_keys(rpmtxn txn, rpmKeyring keyring);
+    virtual rpmRC import_key(rpmtxn txn, rpmPubkey key, int replace = 1, rpmFlags flags = 0);
+    virtual rpmRC delete_key(rpmtxn txn, rpmPubkey key);
+};
+
 }; /* namespace */
 
 #endif /* _KEYSTORE_H */

lib/rpmts.cc

@@ -275,6 +275,8 @@ static keystore *getKeystore(rpmts ts)
 	    ts->keystore = new keystore_fs();
 	} else if (rstreq(krtype, "rpmdb")) {
 	    ts->keystore = new keystore_rpmdb();
+	} else if (rstreq(krtype, "openpgp")) {
+	    ts->keystore = new keystore_openpgp_cert_d();
 	} else {
 	    /* Fall back to using rpmdb if unknown, for now at least */
 	    rpmlog(RPMLOG_WARNING,

tests/rpmsigdig.at

@@ -264,6 +264,95 @@ runroot rpmkeys -Kv /data/RPMS/hello-2.0-1.x86_64.rpm /data/RPMS/hello-1.0-1.i38
 RPMTEST_CLEANUP
 
 
+AT_SETUP([rpmkeys key update (openpgp)])
+AT_KEYWORDS([rpmkeys signature])
+RPMDB_INIT
+# root's .rpmmacros used to keep this build prefix independent
+echo "%_keyring openpgp" >> "${RPMTEST}"/root/.rpmmacros
+RPMTEST_CHECK([
+runroot rpmkeys --import /data/keys/rpm.org-rsa-2048-test.pub
+runroot rpmkeys -Kv /data/RPMS/hello-2.0-1.x86_64-signed-with-new-subkey.rpm
+],
+[1],
+[/data/RPMS/hello-2.0-1.x86_64-signed-with-new-subkey.rpm:
+    Header OpenPGP V4 EdDSA/SHA512 signature, key ID 6323c42711450b6c: NOKEY
+    Header SHA256 digest: OK
+    Payload SHA256 digest: OK
+],
+[])
+
+RPMTEST_CHECK([
+runroot_other touch /usr/lib/sysimage/rpm/pubkeys/writelock
+runroot rpmkeys --import /data/keys/rpm.org-rsa-2048-add-subkey.asc
+runroot_other rm /usr/lib/sysimage/rpm/pubkeys/writelock
+],
+[0],
+[],
+[error: Can't acquire writelock for keyring at /usr/lib/sysimage/rpm/pubkeys
+error: /data/keys/rpm.org-rsa-2048-add-subkey.asc: key 1 import failed.
+])
+
+
+RPMTEST_CHECK([
+runroot rpmkeys --list | wc -l
+runroot rpmkeys --import /data/keys/rpm.org-rsa-2048-add-subkey.asc
+runroot rpmkeys --list | wc -l
+],
+[0],
+[1
+1
+],
+[])
+
+RPMTEST_CHECK([
+runroot rpmkeys -Kv /data/RPMS/hello-2.0-1.x86_64-signed-with-new-subkey.rpm
+],
+[0],
+[/data/RPMS/hello-2.0-1.x86_64-signed-with-new-subkey.rpm:
+    Header OpenPGP V4 EdDSA/SHA512 signature, key fingerprint: 771b18d3d7baa28734333c424344591e1964c5fc: OK
+    Header SHA256 digest: OK
+    Payload SHA256 digest: OK
+],
+[])
+
+RPMTEST_CHECK([
+runroot rpmkeys --delete abcd gimmekey 1111aaaa2222bbbb
+],
+[1],
+[],
+[error: invalid key id: abcd
+error: invalid key id: gimmekey
+error: key not found: 1111aaaa2222bbbb
+])
+
+RPMTEST_CHECK([
+runroot rpmkeys --delete 1964c5fc
+],
+[0],
+[],
+[])
+
+RPMTEST_CHECK([
+runroot rpmkeys --list | wc -l
+],
+[0],
+[0
+],
+[])
+RPMTEST_CLEANUP
+# ------------------------------
+# Test rpmkeys write errors
+AT_SETUP([[rpmkeys -K no space left on stdout]])
+AT_KEYWORDS([rpmkeys digest])
+RPMTEST_CHECK([
+RPMDB_INIT[
+
+runroot rpmkeys -Kv /data/RPMS/hello-2.0-1.x86_64.rpm /data/RPMS/hello-1.0-1.i386.rpm >/dev/full
+]],255,,[[Error writing to log: No space left on device
+]])
+RPMTEST_CLEANUP
+
+
 AT_SETUP([rpmkeys -Kv <reconstructed> 1])
 AT_KEYWORDS([rpmkeys digest])
 RPMDB_INIT