1 files changed, 391 insertions, 0 deletions
diff --git a/lib/libcapsicum/libcapsicum_pwd.c b/lib/libcapsicum/libcapsicum_pwd.c
new file mode 100644
index 0000000..5b44c34
--- /dev/null
+++ b/lib/libcapsicum/libcapsicum_pwd.c
@@ -0,0 +1,391 @@
+/*-
+ * Copyright (c) 2013 The FreeBSD Foundation
+ * All rights reserved.
+ *
+ * This software was developed by Pawel Jakub Dawidek under sponsorship from
+ * the FreeBSD Foundation.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS 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 AUTHORS 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <sys/nv.h>
+
+#include <assert.h>
+#include <errno.h>
+#include <pwd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "libcapsicum.h"
+#include "libcapsicum_pwd.h"
+
+static struct passwd gpwd;
+static char *gbuffer;
+static size_t gbufsize;
+
+static int
+passwd_resize(void)
+{
+	char *buf;
+
+	if (gbufsize == 0)
+		gbufsize = 1024;
+	else
+		gbufsize *= 2;
+
+	buf = gbuffer;
+	gbuffer = realloc(buf, gbufsize);
+	if (gbuffer == NULL) {
+		free(buf);
+		gbufsize = 0;
+		return (ENOMEM);
+	}
+	memset(gbuffer, 0, gbufsize);
+
+	return (0);
+}
+
+static int
+passwd_unpack_string(const nvlist_t *nvl, const char *fieldname, char **fieldp,
+    char **bufferp, size_t *bufsizep)
+{
+	const char *str;
+	size_t len;
+
+	str = nvlist_get_string(nvl, fieldname);
+	len = strlcpy(*bufferp, str, *bufsizep);
+	if (len >= *bufsizep)
+		return (ERANGE);
+	*fieldp = *bufferp;
+	*bufferp += len + 1;
+	*bufsizep -= len + 1;
+
+	return (0);
+}
+
+static int
+passwd_unpack(const nvlist_t *nvl, struct passwd *pwd, char *buffer,
+    size_t bufsize)
+{
+	int error;
+
+	if (!nvlist_exists_string(nvl, "pw_name"))
+		return (EINVAL);
+
+	memset(pwd, 0, sizeof(*pwd));
+
+	error = passwd_unpack_string(nvl, "pw_name", &pwd->pw_name, &buffer,
+	    &bufsize);
+	if (error != 0)
+		return (error);
+	pwd->pw_uid = (uid_t)nvlist_get_number(nvl, "pw_uid");
+	pwd->pw_gid = (gid_t)nvlist_get_number(nvl, "pw_gid");
+	pwd->pw_change = (time_t)nvlist_get_number(nvl, "pw_change");
+	error = passwd_unpack_string(nvl, "pw_passwd", &pwd->pw_passwd, &buffer,
+	    &bufsize);
+	if (error != 0)
+		return (error);
+	error = passwd_unpack_string(nvl, "pw_class", &pwd->pw_class, &buffer,
+	    &bufsize);
+	if (error != 0)
+		return (error);
+	error = passwd_unpack_string(nvl, "pw_gecos", &pwd->pw_gecos, &buffer,
+	    &bufsize);
+	if (error != 0)
+		return (error);
+	error = passwd_unpack_string(nvl, "pw_dir", &pwd->pw_dir, &buffer,
+	    &bufsize);
+	if (error != 0)
+		return (error);
+	error = passwd_unpack_string(nvl, "pw_shell", &pwd->pw_shell, &buffer,
+	    &bufsize);
+	if (error != 0)
+		return (error);
+	pwd->pw_expire = (time_t)nvlist_get_number(nvl, "pw_expire");
+	pwd->pw_fields = (int)nvlist_get_number(nvl, "pw_fields");
+
+	return (0);
+}
+
+static int
+cap_getpwcommon_r(cap_channel_t *chan, const char *cmd, const char *login,
+    uid_t uid, struct passwd *pwd, char *buffer, size_t bufsize,
+    struct passwd **result)
+{
+	nvlist_t *nvl;
+	bool getpw_r;
+	int error;
+
+	nvl = nvlist_create(0);
+	nvlist_add_string(nvl, "cmd", cmd);
+	if (strcmp(cmd, "getpwent") == 0 || strcmp(cmd, "getpwent_r") == 0) {
+		/* Add nothing. */
+	} else if (strcmp(cmd, "getpwnam") == 0 ||
+	    strcmp(cmd, "getpwnam_r") == 0) {
+		nvlist_add_string(nvl, "name", login);
+	} else if (strcmp(cmd, "getpwuid") == 0 ||
+	    strcmp(cmd, "getpwuid_r") == 0) {
+		nvlist_add_number(nvl, "uid", (uint64_t)uid);
+	} else {
+		abort();
+	}
+	nvl = cap_xfer_nvlist(chan, nvl, 0);
+	if (nvl == NULL) {
+		assert(errno != 0);
+		*result = NULL;
+		return (errno);
+	}
+	error = (int)nvlist_get_number(nvl, "error");
+	if (error != 0) {
+		nvlist_destroy(nvl);
+		*result = NULL;
+		return (error);
+	}
+
+	if (!nvlist_exists_string(nvl, "pw_name")) {
+		/* Not found. */
+		nvlist_destroy(nvl);
+		*result = NULL;
+		return (0);
+	}
+
+	getpw_r = (strcmp(cmd, "getpwent_r") == 0 ||
+	    strcmp(cmd, "getpwnam_r") == 0 || strcmp(cmd, "getpwuid_r") == 0);
+
+	for (;;) {
+		error = passwd_unpack(nvl, pwd, buffer, bufsize);
+		if (getpw_r || error != ERANGE)
+			break;
+		assert(buffer == gbuffer);
+		assert(bufsize == gbufsize);
+		error = passwd_resize();
+		if (error != 0)
+			break;
+		/* Update pointers after resize. */
+		buffer = gbuffer;
+		bufsize = gbufsize;
+	}
+
+	nvlist_destroy(nvl);
+
+	if (error == 0)
+		*result = pwd;
+	else
+		*result = NULL;
+
+	return (error);
+}
+
+static struct passwd *
+cap_getpwcommon(cap_channel_t *chan, const char *cmd, const char *login,
+    uid_t uid)
+{
+	struct passwd *result;
+	int error, serrno;
+
+	serrno = errno;
+
+	error = cap_getpwcommon_r(chan, cmd, login, uid, &gpwd, gbuffer,
+	    gbufsize, &result);
+	if (error != 0) {
+		errno = error;
+		return (NULL);
+	}
+
+	errno = serrno;
+
+	return (result);
+}
+
+struct passwd *
+cap_getpwent(cap_channel_t *chan)
+{
+
+	return (cap_getpwcommon(chan, "getpwent", NULL, 0));
+}
+
+struct passwd *
+cap_getpwnam(cap_channel_t *chan, const char *login)
+{
+
+	return (cap_getpwcommon(chan, "getpwnam", login, 0));
+}
+
+struct passwd *
+cap_getpwuid(cap_channel_t *chan, uid_t uid)
+{
+
+	return (cap_getpwcommon(chan, "getpwuid", NULL, uid));
+}
+
+int
+cap_getpwent_r(cap_channel_t *chan, struct passwd *pwd, char *buffer,
+    size_t bufsize, struct passwd **result)
+{
+
+	return (cap_getpwcommon_r(chan, "getpwent_r", NULL, 0, pwd, buffer,
+	    bufsize, result));
+}
+
+int
+cap_getpwnam_r(cap_channel_t *chan, const char *name, struct passwd *pwd,
+    char *buffer, size_t bufsize, struct passwd **result)
+{
+
+	return (cap_getpwcommon_r(chan, "getpwnam_r", name, 0, pwd, buffer,
+	    bufsize, result));
+}
+
+int
+cap_getpwuid_r(cap_channel_t *chan, uid_t uid, struct passwd *pwd, char *buffer,
+    size_t bufsize, struct passwd **result)
+{
+
+	return (cap_getpwcommon_r(chan, "getpwuid_r", NULL, uid, pwd, buffer,
+	    bufsize, result));
+}
+
+int
+cap_setpassent(cap_channel_t *chan, int stayopen)
+{
+	nvlist_t *nvl;
+
+	nvl = nvlist_create(0);
+	nvlist_add_string(nvl, "cmd", "setpassent");
+	nvlist_add_bool(nvl, "stayopen", stayopen != 0);
+	nvl = cap_xfer_nvlist(chan, nvl, 0);
+	if (nvl == NULL)
+		return (0);
+	if (nvlist_get_number(nvl, "error") != 0) {
+		errno = nvlist_get_number(nvl, "error");
+		nvlist_destroy(nvl);
+		return (0);
+	}
+	nvlist_destroy(nvl);
+
+	return (1);
+}
+
+static void
+cap_set_end_pwent(cap_channel_t *chan, const char *cmd)
+{
+	nvlist_t *nvl;
+
+	nvl = nvlist_create(0);
+	nvlist_add_string(nvl, "cmd", cmd);
+	/* Ignore any errors, we have no way to report them. */
+	nvlist_destroy(cap_xfer_nvlist(chan, nvl, 0));
+}
+
+void
+cap_setpwent(cap_channel_t *chan)
+{
+
+	cap_set_end_pwent(chan, "setpwent");
+}
+
+void
+cap_endpwent(cap_channel_t *chan)
+{
+
+	cap_set_end_pwent(chan, "endpwent");
+}
+
+int
+cap_pwd_limit_cmds(cap_channel_t *chan, const char * const *cmds, size_t ncmds)
+{
+	nvlist_t *limits, *nvl;
+	unsigned int i;
+
+	if (cap_limit_get(chan, &limits) < 0)
+		return (-1);
+	if (limits == NULL) {
+		limits = nvlist_create(0);
+	} else {
+		if (nvlist_exists_nvlist(limits, "cmds"))
+			nvlist_free_nvlist(limits, "cmds");
+	}
+	nvl = nvlist_create(0);
+	for (i = 0; i < ncmds; i++)
+		nvlist_add_null(nvl, cmds[i]);
+	nvlist_move_nvlist(limits, "cmds", nvl);
+	return (cap_limit_set(chan, limits));
+}
+
+int
+cap_pwd_limit_fields(cap_channel_t *chan, const char * const *fields,
+    size_t nfields)
+{
+	nvlist_t *limits, *nvl;
+	unsigned int i;
+
+	if (cap_limit_get(chan, &limits) < 0)
+		return (-1);
+	if (limits == NULL) {
+		limits = nvlist_create(0);
+	} else {
+		if (nvlist_exists_nvlist(limits, "fields"))
+			nvlist_free_nvlist(limits, "fields");
+	}
+	nvl = nvlist_create(0);
+	for (i = 0; i < nfields; i++)
+		nvlist_add_null(nvl, fields[i]);
+	nvlist_move_nvlist(limits, "fields", nvl);
+	return (cap_limit_set(chan, limits));
+}
+
+int
+cap_pwd_limit_users(cap_channel_t *chan, const char * const *names,
+    size_t nnames, uid_t *uids, size_t nuids)
+{
+	nvlist_t *limits, *users;
+	char nvlname[64];
+	unsigned int i;
+	int n;
+
+	if (cap_limit_get(chan, &limits) < 0)
+		return (-1);
+	if (limits == NULL) {
+		limits = nvlist_create(0);
+	} else {
+		if (nvlist_exists_nvlist(limits, "users"))
+			nvlist_free_nvlist(limits, "users");
+	}
+	users = nvlist_create(0);
+	for (i = 0; i < nuids; i++) {
+		n = snprintf(nvlname, sizeof(nvlname), "uid%u", i);
+		assert(n > 0 && n < (int)sizeof(nvlname));
+		nvlist_add_number(users, nvlname, (uint64_t)uids[i]);
+	}
+	for (i = 0; i < nnames; i++) {
+		n = snprintf(nvlname, sizeof(nvlname), "name%u", i);
+		assert(n > 0 && n < (int)sizeof(nvlname));
+		nvlist_add_string(users, nvlname, names[i]);
+	}
+	nvlist_move_nvlist(limits, "users", users);
+	return (cap_limit_set(chan, limits));
+}