common, client: Move runtime directory detection to libp11-common

1 files changed, 111 insertions, 0 deletions

diff --git a/common/runtime.c b/common/runtime.c
new file mode 100644
index 0000000..f713e7d
--- /dev/null
+++ b/common/runtime.c
@@ -0,0 +1,111 @@
+/*
+ * Copyright (c) 2018 Red Hat Inc
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *     * Redistributions of source code must retain the above
+ *       copyright notice, this list of conditions and the
+ *       following disclaimer.
+ *     * Redistributions in binary form must reproduce the
+ *       above copyright notice, this list of conditions and
+ *       the following disclaimer in the documentation and/or
+ *       other materials provided with the distribution.
+ *     * The names of contributors to this software may not be
+ *       used to endorse or promote products derived from this
+ *       software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+ * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * Author: Daiki Ueno
+ */
+
+#include "config.h"
+
+#include "runtime.h"
+
+#include "compat.h"
+#include <pwd.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+static const char * const _p11_runtime_bases_default[] = { "/run", "/var/run", NULL };
+const char * const *_p11_runtime_bases = _p11_runtime_bases_default;
+
+CK_RV
+p11_get_runtime_directory (char **directoryp)
+{
+	const char *envvar;
+	const char * const *bases = _p11_runtime_bases;
+	char prefix[13 + 1 + 20 + 6 + 1];
+	char *directory;
+	uid_t uid;
+	struct stat sb;
+	struct passwd pwbuf, *pw;
+	char buf[1024];
+	int i;
+
+	/* We can't always assume the XDG_RUNTIME_DIR envvar here,
+	 * because the PKCS#11 module can be loaded by a program that
+	 * calls setuid().  */
+	envvar = secure_getenv ("XDG_RUNTIME_DIR");
+
+	if (envvar != NULL && envvar[0] != '\0') {
+		directory = strdup (envvar);
+		if (!directory)
+			return CKR_HOST_MEMORY;
+
+		*directoryp = directory;
+		return CKR_OK;
+	}
+
+	uid = getuid ();
+
+	for (i = 0; bases[i] != NULL; i++) {
+		snprintf (prefix, sizeof prefix, "%s/user/%u",
+			  bases[i], (unsigned int) uid);
+		if (stat (prefix, &sb) != -1 && S_ISDIR (sb.st_mode)) {
+			directory = strdup (prefix);
+			if (!directory)
+				return CKR_HOST_MEMORY;
+			*directoryp = directory;
+			return CKR_OK;
+		}
+	}
+
+	/* We can't use /run/user/<UID>, fallback to ~/.cache.  */
+	envvar = secure_getenv ("XDG_CACHE_HOME");
+
+	if (envvar != NULL && envvar[0] != '\0') {
+		directory = strdup (envvar);
+		if (!directory)
+			return CKR_HOST_MEMORY;
+
+		*directoryp = directory;
+		return CKR_OK;
+	}
+
+	if (getpwuid_r (uid, &pwbuf, buf, sizeof buf, &pw) < 0 ||
+	    pw == NULL || pw->pw_dir == NULL || *pw->pw_dir != '/')
+		return CKR_GENERAL_ERROR;
+
+	if (asprintf (&directory, "%s/.cache", pw->pw_dir) < 0)
+		return CKR_HOST_MEMORY;
+	*directoryp = directory;
+	return CKR_OK;
+}