--- /dev/null
+/**
+ * Seccomp Library API
+ *
+ * Copyright (c) 2012,2013 Red Hat <pmoore@redhat.com>
+ * Author: Paul Moore <paul@paul-moore.com>
+ */
+
+/*
+ * This library is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This library is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library; if not, see <http://www.gnu.org/licenses>.
+ */
+
+#include <endian.h>
+#include <errno.h>
+#include <inttypes.h>
+#include <unistd.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdbool.h>
+
+#include <seccomp.h>
+
+#include "arch.h"
+#include "db.h"
+#include "gen_pfc.h"
+#include "gen_bpf.h"
+#include "system.h"
+
+#define API __attribute__((visibility("default")))
+
+const struct scmp_version library_version = {
+ .major = SCMP_VER_MAJOR,
+ .minor = SCMP_VER_MINOR,
+ .micro = SCMP_VER_MICRO,
+};
+
+/**
+ * Validate a filter context
+ * @param ctx the filter context
+ *
+ * Attempt to validate the provided filter context. Returns zero if the
+ * context is valid, negative values on failure.
+ *
+ */
+static int _ctx_valid(const scmp_filter_ctx *ctx)
+{
+ return db_col_valid((struct db_filter_col *)ctx);
+}
+
+/**
+ * Validate a syscall number
+ * @param syscall the syscall number
+ *
+ * Attempt to perform basic syscall number validation. Returns zero of the
+ * syscall appears valid, negative values on failure.
+ *
+ */
+static int _syscall_valid(int syscall)
+{
+ if (syscall <= -1 && syscall >= -99)
+ return -EINVAL;
+ return 0;
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API const struct scmp_version *seccomp_version(void)
+{
+ return &library_version;
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API scmp_filter_ctx seccomp_init(uint32_t def_action)
+{
+ if (db_action_valid(def_action) < 0)
+ return NULL;
+
+ return db_col_init(def_action);
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API int seccomp_reset(scmp_filter_ctx ctx, uint32_t def_action)
+{
+ struct db_filter_col *col = (struct db_filter_col *)ctx;
+
+ if (ctx == NULL || db_action_valid(def_action) < 0)
+ return -EINVAL;
+
+ return db_col_reset(col, def_action);
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API void seccomp_release(scmp_filter_ctx ctx)
+{
+ db_col_release((struct db_filter_col *)ctx);
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API int seccomp_merge(scmp_filter_ctx ctx_dst,
+ scmp_filter_ctx ctx_src)
+{
+ struct db_filter_col *col_dst = (struct db_filter_col *)ctx_dst;
+ struct db_filter_col *col_src = (struct db_filter_col *)ctx_src;
+
+ if (db_col_valid(col_dst) || db_col_valid(col_src))
+ return -EINVAL;
+
+ /* NOTE: only the default action, NNP, and TSYNC settings must match */
+ if ((col_dst->attr.act_default != col_src->attr.act_default) ||
+ (col_dst->attr.nnp_enable != col_src->attr.nnp_enable) ||
+ (col_dst->attr.tsync_enable != col_src->attr.tsync_enable))
+ return -EINVAL;
+
+ return db_col_merge(col_dst, col_src);
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API uint32_t seccomp_arch_resolve_name(const char *arch_name)
+{
+ const struct arch_def *arch;
+
+ if (arch_name == NULL)
+ return 0;
+
+ arch = arch_def_lookup_name(arch_name);
+ if (arch == NULL)
+ return 0;
+
+ return arch->token;
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API uint32_t seccomp_arch_native(void)
+{
+ return arch_def_native->token;
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API int seccomp_arch_exist(const scmp_filter_ctx ctx,
+ uint32_t arch_token)
+{
+ struct db_filter_col *col = (struct db_filter_col *)ctx;
+
+ if (arch_token == 0)
+ arch_token = arch_def_native->token;
+
+ if (arch_valid(arch_token))
+ return -EINVAL;
+
+ return (db_col_arch_exist(col, arch_token) ? 0 : -EEXIST);
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API int seccomp_arch_add(scmp_filter_ctx ctx, uint32_t arch_token)
+{
+ const struct arch_def *arch;
+ struct db_filter_col *col = (struct db_filter_col *)ctx;
+
+ if (arch_token == 0)
+ arch_token = arch_def_native->token;
+
+ if (arch_valid(arch_token))
+ return -EINVAL;
+ if (db_col_arch_exist(col, arch_token))
+ return -EEXIST;
+
+ arch = arch_def_lookup(arch_token);
+ if (arch == NULL)
+ return -EFAULT;
+ return db_col_db_new(col, arch);
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API int seccomp_arch_remove(scmp_filter_ctx ctx, uint32_t arch_token)
+{
+ struct db_filter_col *col = (struct db_filter_col *)ctx;
+
+ if (arch_token == 0)
+ arch_token = arch_def_native->token;
+
+ if (arch_valid(arch_token))
+ return -EINVAL;
+ if (db_col_arch_exist(col, arch_token) != -EEXIST)
+ return -EEXIST;
+
+ return db_col_db_remove(col, arch_token);
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API int seccomp_load(const scmp_filter_ctx ctx)
+{
+ struct db_filter_col *col;
+
+ if (_ctx_valid(ctx))
+ return -EINVAL;
+ col = (struct db_filter_col *)ctx;
+
+ return sys_filter_load(col);
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API int seccomp_attr_get(const scmp_filter_ctx ctx,
+ enum scmp_filter_attr attr, uint32_t *value)
+{
+ if (_ctx_valid(ctx))
+ return -EINVAL;
+
+ return db_col_attr_get((const struct db_filter_col *)ctx, attr, value);
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API int seccomp_attr_set(scmp_filter_ctx ctx,
+ enum scmp_filter_attr attr, uint32_t value)
+{
+ if (_ctx_valid(ctx))
+ return -EINVAL;
+
+ return db_col_attr_set((struct db_filter_col *)ctx, attr, value);
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API char *seccomp_syscall_resolve_num_arch(uint32_t arch_token, int num)
+{
+ const struct arch_def *arch;
+ const char *name;
+
+ if (arch_token == 0)
+ arch_token = arch_def_native->token;
+ if (arch_valid(arch_token))
+ return NULL;
+ arch = arch_def_lookup(arch_token);
+ if (arch == NULL)
+ return NULL;
+
+ name = arch_syscall_resolve_num(arch, num);
+ if (name == NULL)
+ return NULL;
+
+ return strdup(name);
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API int seccomp_syscall_resolve_name_arch(uint32_t arch_token, const char *name)
+{
+ const struct arch_def *arch;
+
+ if (name == NULL)
+ return __NR_SCMP_ERROR;
+
+ if (arch_token == 0)
+ arch_token = arch_def_native->token;
+ if (arch_valid(arch_token))
+ return __NR_SCMP_ERROR;
+ arch = arch_def_lookup(arch_token);
+ if (arch == NULL)
+ return __NR_SCMP_ERROR;
+
+ return arch_syscall_resolve_name(arch, name);
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API int seccomp_syscall_resolve_name_rewrite(uint32_t arch_token,
+ const char *name)
+{
+ int rc;
+ int syscall;
+ const struct arch_def *arch;
+
+ if (name == NULL)
+ return __NR_SCMP_ERROR;
+
+ if (arch_token == 0)
+ arch_token = arch_def_native->token;
+ if (arch_valid(arch_token))
+ return __NR_SCMP_ERROR;
+ arch = arch_def_lookup(arch_token);
+ if (arch == NULL)
+ return __NR_SCMP_ERROR;
+
+ syscall = arch_syscall_resolve_name(arch, name);
+ if (syscall == __NR_SCMP_ERROR)
+ return __NR_SCMP_ERROR;
+ rc = arch_syscall_rewrite(arch, &syscall);
+ if (rc == -EDOM)
+ /* if we can't rewrite the syscall, just pass it through */
+ return syscall;
+ else if (rc < 0)
+ return __NR_SCMP_ERROR;
+
+ return syscall;
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API int seccomp_syscall_resolve_name(const char *name)
+{
+ return seccomp_syscall_resolve_name_arch(SCMP_ARCH_NATIVE, name);
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API int seccomp_syscall_priority(scmp_filter_ctx ctx,
+ int syscall, uint8_t priority)
+{
+ struct db_filter_col *col = (struct db_filter_col *)ctx;
+
+ if (db_col_valid(col) || _syscall_valid(syscall))
+ return -EINVAL;
+
+ return db_col_syscall_priority(col, syscall, priority);
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API int seccomp_rule_add_array(scmp_filter_ctx ctx,
+ uint32_t action, int syscall,
+ unsigned int arg_cnt,
+ const struct scmp_arg_cmp *arg_array)
+{
+ int rc;
+ struct db_filter_col *col = (struct db_filter_col *)ctx;
+
+ if (arg_cnt > ARG_COUNT_MAX)
+ return -EINVAL;
+ if (arg_cnt > 0 && arg_array == NULL)
+ return -EINVAL;
+
+ if (db_col_valid(col) || _syscall_valid(syscall))
+ return -EINVAL;
+
+ rc = db_action_valid(action);
+ if (rc < 0)
+ return rc;
+ if (action == col->attr.act_default)
+ return -EPERM;
+
+ return db_col_rule_add(col, 0, action, syscall, arg_cnt, arg_array);
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API int seccomp_rule_add(scmp_filter_ctx ctx,
+ uint32_t action, int syscall,
+ unsigned int arg_cnt, ...)
+{
+ int rc;
+ int iter;
+ struct scmp_arg_cmp arg_array[ARG_COUNT_MAX];
+ va_list arg_list;
+
+ /* arg_cnt is unsigned, so no need to check the lower bound */
+ if (arg_cnt > ARG_COUNT_MAX)
+ return -EINVAL;
+
+ va_start(arg_list, arg_cnt);
+ for (iter = 0; iter < arg_cnt; ++iter)
+ arg_array[iter] = va_arg(arg_list, struct scmp_arg_cmp);
+ rc = seccomp_rule_add_array(ctx, action, syscall, arg_cnt, arg_array);
+ va_end(arg_list);
+
+ return rc;
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API int seccomp_rule_add_exact_array(scmp_filter_ctx ctx,
+ uint32_t action, int syscall,
+ unsigned int arg_cnt,
+ const struct scmp_arg_cmp *arg_array)
+{
+ int rc;
+ struct db_filter_col *col = (struct db_filter_col *)ctx;
+
+ if (arg_cnt > ARG_COUNT_MAX)
+ return -EINVAL;
+ if (arg_cnt > 0 && arg_array == NULL)
+ return -EINVAL;
+
+ if (db_col_valid(col) || _syscall_valid(syscall))
+ return -EINVAL;
+
+ rc = db_action_valid(action);
+ if (rc < 0)
+ return rc;
+ if (action == col->attr.act_default)
+ return -EPERM;
+
+ if (col->filter_cnt > 1)
+ return -EOPNOTSUPP;
+
+ return db_col_rule_add(col, 1, action, syscall, arg_cnt, arg_array);
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API int seccomp_rule_add_exact(scmp_filter_ctx ctx,
+ uint32_t action, int syscall,
+ unsigned int arg_cnt, ...)
+{
+ int rc;
+ int iter;
+ struct scmp_arg_cmp arg_array[ARG_COUNT_MAX];
+ va_list arg_list;
+
+ /* arg_cnt is unsigned, so no need to check the lower bound */
+ if (arg_cnt > ARG_COUNT_MAX)
+ return -EINVAL;
+
+ va_start(arg_list, arg_cnt);
+ for (iter = 0; iter < arg_cnt; ++iter)
+ arg_array[iter] = va_arg(arg_list, struct scmp_arg_cmp);
+ rc = seccomp_rule_add_exact_array(ctx,
+ action, syscall, arg_cnt, arg_array);
+ va_end(arg_list);
+
+ return rc;
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API int seccomp_export_pfc(const scmp_filter_ctx ctx, int fd)
+{
+ if (_ctx_valid(ctx))
+ return -EINVAL;
+
+ return gen_pfc_generate((struct db_filter_col *)ctx, fd);
+}
+
+/* NOTE - function header comment in include/seccomp.h */
+API int seccomp_export_bpf(const scmp_filter_ctx ctx, int fd)
+{
+ int rc;
+ struct bpf_program *program;
+
+ if (_ctx_valid(ctx))
+ return -EINVAL;
+
+ program = gen_bpf_generate((struct db_filter_col *)ctx);
+ if (program == NULL)
+ return -ENOMEM;
+ rc = write(fd, program->blks, BPF_PGM_SIZE(program));
+ gen_bpf_release(program);
+ if (rc < 0)
+ return -errno;
+
+ return 0;
+}
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