add tools

1 files changed, 235 insertions, 0 deletions

diff --git a/usr.bin/doas/env.c b/usr.bin/doas/env.c
new file mode 100644
index 0000000..2d93a40
--- /dev/null
+++ b/usr.bin/doas/env.c
@@ -0,0 +1,235 @@
+/* $OpenBSD: env.c,v 1.10 2019/07/07 19:21:28 tedu Exp $ */
+/*
+ * Copyright (c) 2016 Ted Unangst <tedu@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+#include <sys/tree.h>
+
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <err.h>
+#include <unistd.h>
+#include <errno.h>
+#include <pwd.h>
+
+#include "doas.h"
+
+const char *formerpath;
+
+struct envnode {
+	RB_ENTRY(envnode) node;
+	const char *key;
+	const char *value;
+};
+
+struct env {
+	RB_HEAD(envtree, envnode) root;
+	u_int count;
+};
+
+static void fillenv(struct env *env, const char **envlist);
+
+static int
+envcmp(struct envnode *a, struct envnode *b)
+{
+	return strcmp(a->key, b->key);
+}
+RB_GENERATE_STATIC(envtree, envnode, node, envcmp)
+
+static struct envnode *
+createnode(const char *key, const char *value)
+{
+	struct envnode *node;
+
+	node = malloc(sizeof(*node));
+	if (!node)
+		err(1, NULL);
+	node->key = strdup(key);
+	node->value = strdup(value);
+	if (!node->key || !node->value)
+		err(1, NULL);
+	return node;
+}
+
+static void
+freenode(struct envnode *node)
+{
+	free((char *)node->key);
+	free((char *)node->value);
+	free(node);
+}
+
+static void
+addnode(struct env *env, const char *key, const char *value)
+{
+	struct envnode *node;
+
+	node = createnode(key, value);
+	RB_INSERT(envtree, &env->root, node);
+	env->count++;
+}
+
+static struct env *
+createenv(const struct rule *rule, const struct passwd *mypw,
+    const struct passwd *targpw)
+{
+	static const char *copyset[] = {
+		"DISPLAY", "TERM",
+		NULL
+	};
+	struct env *env;
+	u_int i;
+
+	env = malloc(sizeof(*env));
+	if (!env)
+		err(1, NULL);
+	RB_INIT(&env->root);
+	env->count = 0;
+
+	addnode(env, "DOAS_USER", mypw->pw_name);
+	addnode(env, "HOME", targpw->pw_dir);
+	addnode(env, "LOGNAME", targpw->pw_name);
+	addnode(env, "PATH", getenv("PATH"));
+	addnode(env, "SHELL", targpw->pw_shell);
+	addnode(env, "USER", targpw->pw_name);
+
+	fillenv(env, copyset);
+
+	if (rule->options & KEEPENV) {
+		extern const char **environ;
+
+		for (i = 0; environ[i] != NULL; i++) {
+			struct envnode *node;
+			const char *e, *eq;
+			size_t len;
+			char name[1024];
+
+			e = environ[i];
+
+			/* ignore invalid or overlong names */
+			if ((eq = strchr(e, '=')) == NULL || eq == e)
+				continue;
+			len = eq - e;
+			if (len > sizeof(name) - 1)
+				continue;
+			memcpy(name, e, len);
+			name[len] = '\0';
+
+			node = createnode(name, eq + 1);
+			if (RB_INSERT(envtree, &env->root, node)) {
+				/* ignore any later duplicates */
+				freenode(node);
+			} else {
+				env->count++;
+			}
+		}
+	}
+
+	return env;
+}
+
+static char **
+flattenenv(struct env *env)
+{
+	char **envp;
+	struct envnode *node;
+	u_int i;
+
+	envp = reallocarray(NULL, env->count + 1, sizeof(char *));
+	if (!envp)
+		err(1, NULL);
+	i = 0;
+	RB_FOREACH(node, envtree, &env->root) {
+		if (asprintf(&envp[i], "%s=%s", node->key, node->value) == -1)
+			err(1, NULL);
+		i++;
+	}
+	envp[i] = NULL;
+	return envp;
+}
+
+static void
+fillenv(struct env *env, const char **envlist)
+{
+	struct envnode *node, key;
+	const char *e, *eq;
+	const char *val;
+	char name[1024];
+	u_int i;
+	size_t len;
+
+	for (i = 0; envlist[i]; i++) {
+		e = envlist[i];
+
+		/* parse out env name */
+		if ((eq = strchr(e, '=')) == NULL)
+			len = strlen(e);
+		else
+			len = eq - e;
+		if (len > sizeof(name) - 1)
+			continue;
+		memcpy(name, e, len);
+		name[len] = '\0';
+
+		/* delete previous copies */
+		key.key = name;
+		if (*name == '-')
+			key.key = name + 1;
+		if ((node = RB_FIND(envtree, &env->root, &key))) {
+			RB_REMOVE(envtree, &env->root, node);
+			freenode(node);
+			env->count--;
+		}
+		if (*name == '-')
+			continue;
+
+		/* assign value or inherit from environ */
+		if (eq) {
+			val = eq + 1;
+			if (*val == '$') {
+				if (strcmp(val + 1, "PATH") == 0)
+					val = formerpath;
+				else
+					val = getenv(val + 1);
+			}
+		} else {
+			if (strcmp(name, "PATH") == 0)
+				val = formerpath;
+			else
+				val = getenv(name);
+		}
+		/* at last, we have something to insert */
+		if (val) {
+			node = createnode(name, val);
+			RB_INSERT(envtree, &env->root, node);
+			env->count++;
+		}
+	}
+}
+
+char **
+prepenv(const struct rule *rule, const struct passwd *mypw,
+    const struct passwd *targpw)
+{
+	struct env *env;
+
+	env = createenv(rule, mypw, targpw);
+	if (rule->envlist)
+		fillenv(env, rule->envlist);
+
+	return flattenenv(env);
+}