ucode-mod-pkgen: add ucode module for generating crypto keys/certificates
authorFelix Fietkau <nbd@nbd.name>
Fri, 22 Mar 2024 15:21:18 +0000 (16:21 +0100)
committerFelix Fietkau <nbd@nbd.name>
Fri, 13 Dec 2024 10:05:23 +0000 (11:05 +0100)
This also includes a script to use the functionality from the
command line

Signed-off-by: Felix Fietkau <nbd@nbd.name>
package/utils/ucode-mod-pkgen/Makefile [new file with mode: 0644]
package/utils/ucode-mod-pkgen/files/pkgen [new file with mode: 0755]
package/utils/ucode-mod-pkgen/src/CMakeLists.txt [new file with mode: 0644]
package/utils/ucode-mod-pkgen/src/pk.h [new file with mode: 0644]
package/utils/ucode-mod-pkgen/src/pkcs12.c [new file with mode: 0644]
package/utils/ucode-mod-pkgen/src/ucode.c [new file with mode: 0644]

diff --git a/package/utils/ucode-mod-pkgen/Makefile b/package/utils/ucode-mod-pkgen/Makefile
new file mode 100644 (file)
index 0000000..918aa22
--- /dev/null
@@ -0,0 +1,44 @@
+include $(TOPDIR)/rules.mk
+
+PKG_NAME:=ucode-mod-pkgen
+PKG_RELEASE:=1
+PKG_LICENSE:=GPL-2.0-or-later
+PKG_MAINTAINER:=Felix Fietkau <nbd@nbd.name>
+
+include $(INCLUDE_DIR)/package.mk
+include $(INCLUDE_DIR)/cmake.mk
+
+CMAKE_INSTALL := 1
+
+define Package/ucode-mod-pkgen
+  SECTION:=utils
+  CATEGORY:=Utilities
+  TITLE:=ucode module for generating public keys/certificates
+  DEPENDS:=+libucode +libmbedtls
+endef
+
+define Package/ucode-mod-pkgen/description
+The pkgen module provides functionality for generating cryptographic keys and
+(self-)signed certificates. It supports exporting PEM/DER format files, as
+well as PKCS#12 bundle for client cert/key pairs with CA.
+endef
+
+define Package/pkgen
+  SECTION:=utils
+  CATEGORY:=Utilities
+  TITLE:=ucode script for generating public keys/certificates
+  DEPENDS:=+ucode +ucode-mod-pkgen +ucode-mod-fs
+endef
+
+define Package/ucode-mod-pkgen/install
+       $(INSTALL_DIR) $(1)/usr/lib/ucode
+       $(CP) $(PKG_INSTALL_DIR)/usr/lib/ucode/pkgen.so $(1)/usr/lib/ucode/
+endef
+
+define Package/pkgen/install
+       $(INSTALL_DIR) $(1)/usr/bin
+       $(INSTALL_BIN) ./files/pkgen $(1)/usr/bin
+endef
+
+$(eval $(call BuildPackage,ucode-mod-pkgen))
+$(eval $(call BuildPackage,pkgen))
diff --git a/package/utils/ucode-mod-pkgen/files/pkgen b/package/utils/ucode-mod-pkgen/files/pkgen
new file mode 100755 (executable)
index 0000000..e37e5f5
--- /dev/null
@@ -0,0 +1,252 @@
+#!/usr/bin/env ucode
+'use strict';
+
+import { basename, readfile, writefile, stdin } from "fs";
+let pk = require("pkgen");
+let valid_from = "20240101000000";
+let valid_to = "21001231235959";
+let subject, password, password_stdin;
+let keytype = "ec";
+let keylen = 2048;
+let keyexp = 65537;
+let keycurve = "secp256r1";
+let no_ca;
+let legacy;
+
+const usage_message = `Usage: ${basename(sourcepath())} [<options>] <command> [<arguments>]
+
+Commands:
+  ca <ca.pem>:                         Create a new CA.
+                                       (creates ca.pem, ca.key, ca.serial)
+
+  cert <ca.pem> <cert.pem>:            Create a new certificate/key using the CA
+                                       from ca.pem. (creates cert.pem and ca.key)
+
+  cert_p12 <ca.pem> <cert.p12>:                Create a new PKCS#12 certificate/key
+                                       using the CA from ca.pem. (creates ca.p12)
+
+  selfsigned <cert.pem>:               Create a self-signed certificate
+                                       (creates cert.pem)
+
+Options:
+  -C <curve>                           Set EC curve type (default: ${keycurve})
+                                       Possible values: secp521r1, secp384r1, secp256r1,
+                                       secp256k1, secp224r1, secp224k1, secp192r1,
+                                       secp192k1
+  -E <exponent>                                Set RSA key exponent (default: ${keyexp})
+  -L <len>                             Set RSA key length (default: ${keylen})
+  -N                                   Omit CA certificate for PKCS#12 files
+  -p <password>                                Set PKCS#12 password to <password>
+  -P                                   Read PKCS#12 password from stdin
+                                       (default: random password, printed to stdout)
+  -s <name>                            Set subject for generated certificate to <name>.
+  -t rsa|ec                            Set key type to rsa or ec (default: ec)
+  -V <from> <to>                       Set validity for generated certificates.
+                                       (default: ${valid_from} ${valid_to})
+  -W                                   Use weaker PKCS#12 encryption for
+                                       compatibility with Windows and Apple systems
+
+`;
+
+function perror(msg) {
+       let err = pk.errno() == -1 ? "Invalid arguments" : pk.error();
+       warn(`${msg}: ${err}\n`);
+       exit(1);
+}
+
+function usage() {
+       warn(usage_message);
+       exit(1);
+}
+
+function check_pem_path(pem_file) {
+       if (substr(pem_file, -4) != ".pem") {
+               warn(`Path with .pem extension expected\n`);
+               exit(1);
+       }
+
+       return pem_file;
+}
+
+
+function gen_key() {
+       let key = pk.generate_key({
+               type: keytype,
+               curve: keycurve,
+               size: keylen,
+               exponent: keyexp,
+       });
+
+       if (!key)
+               perror("Failed to generate CA key");
+
+       return key;
+}
+
+function gen_cert(key, args) {
+       let cert = pk.generate_cert({
+               subject_name: subject,
+               subject_key: key,
+               validity: [ valid_from, valid_to ],
+               ...args
+       });
+
+       if (!cert)
+               perror("Failed to generate certificate");
+
+       cert = cert.pem();
+       if (!cert)
+               perror("Failed to complete certificate");
+
+       return cert;
+}
+
+function gen_client_cert(ca_file, ca_data, key) {
+       let ca_base = substr(ca_file, 0, -4);
+       let ca_info = pk.cert_info(ca_data);
+       if (!length(ca_info))
+               perror("Failed to load CA certificate");
+
+       let ca_key = pk.load_key(readfile(ca_base + ".key"));
+       if (!ca_key)
+               perror("Failed to load CA key");
+       let ca_serial = +readfile(ca_base + ".serial");
+       if (!ca_serial)
+               perror("Failed to load CA serial");
+
+       let cert = gen_cert(key, {
+               serial: ++ca_serial,
+               issuer_name: ca_info[0].subject,
+               issuer_key: ca_key,
+       });
+       writefile(ca_base + ".serial", "" + ca_serial);
+
+       return cert;
+}
+
+let cmds = {
+       ca: function(args) {
+               let ca_file = check_pem_path(shift(args));
+               let ca_base = substr(ca_file, 0, -4);
+
+               let key = gen_key();
+               let ca_cert = gen_cert(key, {
+                       ca: true,
+                       serial: 1,
+                       issuer_name: subject,
+                       issuer_key: key,
+                       key_usage: [ "key_cert_sign" ],
+               });
+
+               writefile(ca_file, ca_cert);
+               writefile(ca_base + ".key", key.pem());
+               writefile(ca_base + ".serial", "1");
+       },
+
+       cert: function (args) {
+               let ca_file = check_pem_path(shift(args));
+               let crt_file = check_pem_path(shift(args));
+               let crt_base = substr(crt_file, 0, -4);
+
+               let key = gen_key();
+               let ca_data = readfile(ca_file);
+               let cert = gen_client_cert(ca_file, ca_data, key);
+
+               writefile(crt_base + ".key", key.pem());
+               writefile(crt_file, cert);
+       },
+
+       cert_p12: function (args) {
+               let ca_file = check_pem_path(shift(args));
+               let p12_file = shift(args);
+               if (!p12_file)
+                       usage();
+
+               let key = gen_key();
+               let ca_data = readfile(ca_file);
+               let cert = gen_client_cert(ca_file, ca_data, key);
+
+               if (password_stdin)
+                       password = rtrim(stdin.read("line"));
+               else if (!password)
+                       print((password = hexenc(readfile("/dev/urandom", 8))) + "\n");
+
+               let p12 = pk.generate_pkcs12({
+                       password, cert, key, legacy,
+                       extra: no_ca ? null : [ ca_data ],
+               });
+
+               writefile(p12_file, p12);
+       },
+
+       selfsigned: function(args) {
+               let crt_file = check_pem_path(shift(args));
+               let crt_base = substr(crt_file, 0, -4);
+
+               let key = gen_key();
+               let cert = gen_cert(key, {
+                       serial: 1,
+                       issuer_name: subject,
+                       issuer_key: key,
+               });
+
+               writefile(crt_base + ".key", key.pem());
+               writefile(crt_file, cert);
+       },
+};
+
+while (substr(ARGV[0], 0, 1) == "-") {
+       let opt = substr(shift(ARGV), 1);
+       switch (opt) {
+       case 'C':
+               keycurve = shift(ARGV);
+               break;
+       case 'L':
+               keylen = +shift(ARGV);
+               break;
+       case 'N':
+               no_ca = true;
+               break;
+       case 'p':
+               password = shift(ARGV);
+               if (password_stdin)
+                       usage();
+               break;
+       case 'P':
+               password_stdin = true;
+               if (password)
+                       usage();
+               break;
+       case 's':
+               subject = shift(ARGV);
+               break;
+       case 't':
+               keytype = shift(ARGV);
+               if (keytype != "rsa" && keytype != "ec") {
+                       warn(`Unsupported key type ${keytype}\n`);
+                       exit(1);
+               }
+               break;
+       case 'V':
+               valid_from = shift(ARGV);
+               valid_to = shift(ARGV);
+               break;
+       case 'W':
+               legacy = true;
+               break;
+       default:
+               usage();
+               break;
+       }
+}
+
+let cmd = shift(ARGV);
+if (!cmd || !cmds[cmd])
+       usage();
+
+if (subject == null) {
+       warn(`Missing -s option\n`);
+       exit(1);
+}
+
+cmds[cmd](ARGV);
diff --git a/package/utils/ucode-mod-pkgen/src/CMakeLists.txt b/package/utils/ucode-mod-pkgen/src/CMakeLists.txt
new file mode 100644 (file)
index 0000000..8794755
--- /dev/null
@@ -0,0 +1,35 @@
+cmake_minimum_required(VERSION 3.13)
+
+PROJECT(ucode-pkgen C)
+ADD_DEFINITIONS(-Os -ggdb -Wall -Werror --std=gnu99 -ffunction-sections -fwrapv -D_GNU_SOURCE)
+
+IF(CMAKE_C_COMPILER_VERSION VERSION_GREATER 6)
+       ADD_DEFINITIONS(-Wextra -Werror=implicit-function-declaration)
+       ADD_DEFINITIONS(-Wformat -Werror=format-security -Werror=format-nonliteral)
+ENDIF()
+ADD_DEFINITIONS(-Wmissing-declarations -Wno-error=unused-variable -Wno-unused-parameter)
+
+IF(APPLE)
+  SET(UCODE_MODULE_LINK_OPTIONS "LINKER:-undefined,dynamic_lookup")
+ELSE()
+  SET(CMAKE_SHARED_LIBRARY_LINK_C_FLAGS "-Wl,--gc-sections")
+ENDIF()
+
+IF(DEBUG)
+  ADD_DEFINITIONS(-DDEBUG -g3 -O0)
+ELSE()
+  ADD_DEFINITIONS(-DNDEBUG)
+ENDIF()
+
+FIND_LIBRARY(mbedtls NAMES mbedtls)
+FIND_LIBRARY(ucode NAMES ucode)
+FIND_PATH(mbedtls_include_dir NAMES mbedtls/pk.h)
+FIND_PATH(ucode_include_dir NAMES ucode/module.h)
+INCLUDE_DIRECTORIES(${mbedtls_include_dir} ${ucode_include_dir})
+
+ADD_LIBRARY(pkgen_lib MODULE ucode.c pkcs12.c)
+SET_TARGET_PROPERTIES(pkgen_lib PROPERTIES OUTPUT_NAME pkgen PREFIX "")
+TARGET_LINK_OPTIONS(pkgen_lib PRIVATE ${UCODE_MODULE_LINK_OPTIONS})
+TARGET_LINK_LIBRARIES(pkgen_lib ${mbedtls})
+
+INSTALL(TARGETS pkgen_lib LIBRARY DESTINATION lib/ucode)
diff --git a/package/utils/ucode-mod-pkgen/src/pk.h b/package/utils/ucode-mod-pkgen/src/pk.h
new file mode 100644 (file)
index 0000000..9e2b316
--- /dev/null
@@ -0,0 +1,45 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2024 Felix Fietkau <nbd@nbd.name>
+ */
+#ifndef __UCODE_PK_H
+#define __UCODE_PK_H
+
+#include <ucode/lib.h>
+#include <ucode/vm.h>
+
+#include <mbedtls/bignum.h>
+#include <mbedtls/pk.h>
+#include <mbedtls/oid.h>
+#include <mbedtls/error.h>
+#include <mbedtls/version.h>
+
+#if MBEDTLS_VERSION_MAJOR < 3
+#define MBEDTLS_LEGACY
+#endif
+
+int random_cb(void *ctx, unsigned char *out, size_t len);
+uc_value_t *uc_generate_pkcs12(uc_vm_t *vm, size_t nargs);
+int64_t get_int_arg(uc_value_t *obj, const char *key, int64_t defval);
+extern int mbedtls_errno;
+extern char buf[32 * 1024];
+
+#define C(ret)                                         \
+       ({                                              \
+               int __ret = (ret);                      \
+               mbedtls_errno = __ret < 0 ? __ret : 0;  \
+               __ret;                                  \
+       })
+
+#define CHECK(ret) do {                                        \
+       if (C(ret) < 0)                                 \
+               return NULL;                            \
+} while (0)
+#define CHECK_INT(ret) do {                            \
+       if (C(ret) < 0)                                 \
+               return -1;                              \
+} while (0)
+
+#define INVALID_ARG()  do { C(-1); return NULL; } while (0)
+
+#endif
diff --git a/package/utils/ucode-mod-pkgen/src/pkcs12.c b/package/utils/ucode-mod-pkgen/src/pkcs12.c
new file mode 100644 (file)
index 0000000..7d23b9d
--- /dev/null
@@ -0,0 +1,612 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2024 Felix Fietkau <nbd@nbd.name>
+ */
+#include "pk.h"
+#include <mbedtls/x509_crt.h>
+#include <mbedtls/ecp.h>
+#include <mbedtls/rsa.h>
+#include <mbedtls/asn1write.h>
+#include <mbedtls/pkcs5.h>
+#include <mbedtls/pkcs12.h>
+#include <mbedtls/base64.h>
+#include <mbedtls/sha1.h>
+
+#define OID_TAG(n) MBEDTLS_OID_##n, MBEDTLS_OID_SIZE(MBEDTLS_OID_##n)
+
+#ifndef MBEDTLS_OID_AES_256_CBC
+#define MBEDTLS_OID_AES_256_CBC MBEDTLS_OID_AES "\x2a"
+#endif
+
+#define MBEDTLS_OID_PKCS9_LOCAL_KEY_ID         MBEDTLS_OID_PKCS9  "\x15"
+#define MBEDTLS_OID_PKCS9_CERT_TYPE            MBEDTLS_OID_PKCS9  "\x16"
+#define MBEDTLS_OID_PKCS9_CERT_TYPE_X509       MBEDTLS_OID_PKCS9_CERT_TYPE "\x01"
+
+#define MBEDTLS_OID_PKCS12_KEY_BAG             MBEDTLS_OID_PKCS12 "\x0a\x01\x01"
+#define MBEDTLS_OID_PKCS12_SHROUDED_KEY_BAG    MBEDTLS_OID_PKCS12 "\x0a\x01\x02"
+#define MBEDTLS_OID_PKCS12_CERT_BAG            MBEDTLS_OID_PKCS12 "\x0a\x01\x03"
+
+#ifndef MBEDTLS_OID_PKCS7
+#define MBEDTLS_OID_PKCS7                      MBEDTLS_OID_PKCS "\x07"
+#define MBEDTLS_OID_PKCS7_DATA                 MBEDTLS_OID_PKCS7 "\x01"
+#define MBEDTLS_OID_PKCS7_ENCRYPTED_DATA       MBEDTLS_OID_PKCS7 "\x06"
+#endif
+
+#define NUM_ITER 2048
+#define SALT_LEN 16
+#define IV_LEN 16
+#define IV_LEN_LEGACY 8
+#define KEY_LEN 32
+#define CERT_HASH_LEN 20
+
+#define CONTEXT_TAG(n) (MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | (n))
+#define SEQUENCE_TAG (MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)
+#define SET_TAG (MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SET)
+
+#define CTX_ADD(ctx, n) \
+       do {                                            \
+               int __n = (n);                          \
+               if ((ctx)->p - (ctx)->start <= __n)     \
+                       return -1;                      \
+               (ctx)->p -= __n;                        \
+       } while (0)
+
+struct pkcs12_ctx {
+       uint8_t *p, *start;
+
+       uint8_t cert_hash[20];
+       uint8_t *key_cert_hash;
+
+       uint8_t salt[SALT_LEN];
+       uint8_t iv[IV_LEN];
+
+       const char *password;
+       uint8_t *pwd;
+       size_t pwd_len;
+
+       bool legacy;
+};
+
+#ifdef MBEDTLS_LEGACY
+static inline int
+mbedtls_pkcs5_pbkdf2_hmac_ext(mbedtls_md_type_t md_alg, const unsigned char *password,
+                             size_t plen, const unsigned char *salt, size_t slen,
+                             unsigned int iteration_count,
+                             uint32_t key_length, unsigned char *output)
+{
+       mbedtls_md_context_t md_ctx;
+       const mbedtls_md_info_t *md_info;
+       int ret;
+
+       md_info = mbedtls_md_info_from_type(md_alg);
+       if (!md_info)
+               return MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE;
+
+       mbedtls_md_init(&md_ctx);
+       ret = mbedtls_md_setup(&md_ctx, md_info, 1);
+       if (ret)
+               goto out;
+
+       ret = mbedtls_pkcs5_pbkdf2_hmac(&md_ctx, password, plen, salt, slen,
+                                       iteration_count, key_length, output);
+
+out:
+       mbedtls_md_free(&md_ctx);
+       return ret;
+}
+#endif
+
+static void
+uc_p12_add_tag(struct pkcs12_ctx *ctx, uint8_t *end, uint8_t tag)
+{
+       mbedtls_asn1_write_len(&ctx->p, ctx->start, end - ctx->p);
+       mbedtls_asn1_write_tag(&ctx->p, ctx->start, tag);
+}
+
+static void
+uc_p12_add_sequence(struct pkcs12_ctx *ctx, uint8_t *end)
+{
+       uc_p12_add_tag(ctx, end, SEQUENCE_TAG);
+}
+
+static void
+uc_p12_add_algo(struct pkcs12_ctx *ctx, const char *oid, size_t oid_len, size_t par_len)
+{
+       mbedtls_asn1_write_algorithm_identifier(&ctx->p, ctx->start, oid, oid_len, par_len);
+}
+
+static void
+uc_p12_add_attribute(struct pkcs12_ctx *ctx, uint8_t *end, const char *oid, size_t oid_len)
+{
+       uc_p12_add_tag(ctx, end, SET_TAG);
+       mbedtls_asn1_write_oid(&ctx->p, ctx->start, oid, oid_len);
+       uc_p12_add_sequence(ctx, end);
+}
+
+static void
+uc_p12_add_localkeyid(struct pkcs12_ctx *ctx, bool key)
+{
+       uint8_t *end = ctx->p;
+
+       ctx->p -= CERT_HASH_LEN;
+       if (key)
+               ctx->key_cert_hash = ctx->p;
+       else if (ctx->key_cert_hash)
+               memcpy(ctx->p, ctx->key_cert_hash, CERT_HASH_LEN);
+       uc_p12_add_tag(ctx, end, MBEDTLS_ASN1_OCTET_STRING);
+       uc_p12_add_attribute(ctx, end, OID_TAG(PKCS9_LOCAL_KEY_ID));
+}
+
+static void
+uc_p12_add_bag(struct pkcs12_ctx *ctx, uint8_t *data_end, uint8_t *end, const char *oid, size_t oid_len)
+{
+       uc_p12_add_tag(ctx, data_end, CONTEXT_TAG(0));
+       mbedtls_asn1_write_oid(&ctx->p, ctx->start, oid, oid_len);
+       uc_p12_add_sequence(ctx, end);
+}
+
+static int
+uc_p12_enc_setup(struct pkcs12_ctx *ctx, mbedtls_cipher_context_t *cipher)
+{
+       const mbedtls_cipher_info_t *cipher_info;
+       uint8_t key[KEY_LEN];
+       int ret;
+
+       random_cb(NULL, ctx->iv, IV_LEN);
+       ret = mbedtls_pkcs5_pbkdf2_hmac_ext(MBEDTLS_MD_SHA256,
+                                           (void *)ctx->password, strlen(ctx->password),
+                                           ctx->salt, SALT_LEN, NUM_ITER,
+                                           KEY_LEN, key);
+       if (ret < 0)
+               return ret;
+
+       cipher_info = mbedtls_cipher_info_from_type(MBEDTLS_CIPHER_AES_256_CBC);
+       ret = mbedtls_cipher_setup(cipher, cipher_info);
+       if (ret < 0)
+               return ret;
+
+       return mbedtls_cipher_setkey(cipher, key, 8 * KEY_LEN, MBEDTLS_ENCRYPT);
+}
+
+static int
+uc_p12_enc_legacy(struct pkcs12_ctx *ctx, mbedtls_cipher_context_t *cipher)
+{
+       const mbedtls_cipher_info_t *cipher_info;
+       uint8_t key[24];
+       int ret;
+
+       ret = mbedtls_pkcs12_derivation(key, sizeof(key), ctx->pwd, ctx->pwd_len,
+                                       ctx->salt, SALT_LEN, MBEDTLS_MD_SHA1,
+                                       MBEDTLS_PKCS12_DERIVE_KEY, NUM_ITER);
+       if (ret < 0)
+               return ret;
+
+       ret = mbedtls_pkcs12_derivation(ctx->iv, IV_LEN_LEGACY, ctx->pwd, ctx->pwd_len,
+                                       ctx->salt, SALT_LEN, MBEDTLS_MD_SHA1,
+                                       MBEDTLS_PKCS12_DERIVE_IV, NUM_ITER);
+       if (ret < 0)
+               return ret;
+
+       cipher_info = mbedtls_cipher_info_from_type(MBEDTLS_CIPHER_DES_EDE3_CBC);
+       ret = mbedtls_cipher_setup(cipher, cipher_info);
+       if (ret < 0)
+               return ret;
+
+       return mbedtls_cipher_setkey(cipher, key, 8 * sizeof(key), MBEDTLS_ENCRYPT);
+}
+
+static int
+uc_p12_encrypt(struct pkcs12_ctx *ctx, uint8_t *end)
+{
+       mbedtls_cipher_context_t cipher;
+       size_t iv_len = ctx->legacy ? IV_LEN_LEGACY : IV_LEN;
+       size_t out_len = 0;
+       int ret;
+
+       random_cb(NULL, ctx->salt, SALT_LEN);
+
+       if (ctx->legacy)
+               ret = uc_p12_enc_legacy(ctx, &cipher);
+       else
+               ret = uc_p12_enc_setup(ctx, &cipher);
+       if (ret < 0)
+               goto out;
+
+       ret = mbedtls_cipher_set_padding_mode(&cipher, MBEDTLS_PADDING_PKCS7);
+       if (ret < 0)
+               goto out;
+
+       ret = mbedtls_cipher_crypt(&cipher, ctx->iv, iv_len, ctx->p, end - ctx->p,
+                                  (void *)buf, &out_len);
+
+       if (ret < 0)
+               goto out;
+
+       CTX_ADD(ctx, out_len - (end - ctx->p));
+       memcpy(ctx->p, buf, out_len);
+       uc_p12_add_tag(ctx, end, MBEDTLS_ASN1_OCTET_STRING);
+
+out:
+       mbedtls_cipher_free(&cipher);
+
+       return ret;
+}
+
+static int
+uc_p12_add_enc_params(struct pkcs12_ctx *ctx)
+{
+       uint8_t *par_end = ctx->p;
+       uint8_t *kdf_end;
+
+       if (ctx->legacy) {
+               mbedtls_asn1_write_int(&ctx->p, ctx->start, NUM_ITER);
+
+               CTX_ADD(ctx, SALT_LEN);
+               memcpy(ctx->p, ctx->salt, SALT_LEN);
+               uc_p12_add_tag(ctx, ctx->p + SALT_LEN, MBEDTLS_ASN1_OCTET_STRING);
+
+               uc_p12_add_sequence(ctx, par_end);
+
+               uc_p12_add_algo(ctx, OID_TAG(PKCS12_PBE_SHA1_DES3_EDE_CBC), par_end - ctx->p);
+       } else {
+               CTX_ADD(ctx, IV_LEN);
+               memcpy(ctx->p, ctx->iv, IV_LEN);
+
+               uc_p12_add_tag(ctx, par_end, MBEDTLS_ASN1_OCTET_STRING);
+               uc_p12_add_algo(ctx, OID_TAG(AES_256_CBC), par_end - ctx->p);
+
+               kdf_end = ctx->p;
+               uc_p12_add_algo(ctx, OID_TAG(HMAC_SHA256), 0);
+               mbedtls_asn1_write_int(&ctx->p, ctx->start, NUM_ITER);
+               CTX_ADD(ctx, SALT_LEN);
+               memcpy(ctx->p, ctx->salt, SALT_LEN);
+               uc_p12_add_tag(ctx, ctx->p + SALT_LEN, MBEDTLS_ASN1_OCTET_STRING);
+               uc_p12_add_sequence(ctx, kdf_end);
+
+               uc_p12_add_algo(ctx, OID_TAG(PKCS5_PBKDF2), kdf_end - ctx->p);
+               uc_p12_add_sequence(ctx, par_end);
+
+               uc_p12_add_algo(ctx, OID_TAG(PKCS5_PBES2), par_end - ctx->p);
+       }
+
+       return 0;
+}
+
+static int
+uc_p12_add_cert(struct pkcs12_ctx *ctx, uc_value_t *arg, bool ca)
+{
+       const char *str = ucv_string_get(arg), *str_end;
+       uint8_t *bag_end, *end;
+       size_t len;
+       int ret;
+
+#define START_TAG      "-----BEGIN CERTIFICATE-----"
+#define END_TAG                "-----END CERTIFICATE-----"
+
+       if (!str)
+               return -1;
+
+       str = strstr(str, START_TAG);
+       if (!str)
+               return -1;
+
+       str += sizeof(START_TAG);
+       str_end = strstr(str, END_TAG);
+       if (!str_end)
+               return -1;
+
+       if ((size_t)(str_end - str) > sizeof(buf) / 2)
+               return -1;
+
+       ret = mbedtls_base64_decode((void *)buf, sizeof(buf) / 2, &len,
+                                   (const void *)str, str_end - str);
+       if (ret)
+               return ret;
+
+       bag_end = ctx->p;
+       if (!ca && ctx->key_cert_hash) {
+               mbedtls_sha1((const void *)buf, len, ctx->key_cert_hash);
+               uc_p12_add_localkeyid(ctx, false);
+               uc_p12_add_tag(ctx, bag_end, SET_TAG);
+       }
+
+       end = ctx->p;
+       CTX_ADD(ctx, len);
+       memcpy(ctx->p, buf, len);
+       uc_p12_add_tag(ctx, end, MBEDTLS_ASN1_OCTET_STRING);
+
+       /* CertBag */
+       uc_p12_add_tag(ctx, end, CONTEXT_TAG(0));
+       mbedtls_asn1_write_oid(&ctx->p, ctx->start, OID_TAG(PKCS9_CERT_TYPE_X509));
+       uc_p12_add_sequence(ctx, end);
+
+       uc_p12_add_bag(ctx, end, bag_end, OID_TAG(PKCS12_CERT_BAG));
+
+       return 0;
+}
+
+static int
+uc_p12_add_key(struct pkcs12_ctx *ctx, uc_value_t *arg)
+{
+       mbedtls_pk_context *pk = ucv_resource_data(arg, "mbedtls.pk");
+       uint8_t *bag_end, *end;
+       uint8_t *param = NULL;
+       size_t param_len = 0;
+       const char *oid;
+       size_t oid_len = 0;
+       int ret, len;
+
+       if (!pk)
+               return -1;
+
+       bag_end = ctx->p;
+       uc_p12_add_localkeyid(ctx, true);
+       uc_p12_add_tag(ctx, bag_end, SET_TAG);
+
+       end = ctx->p;
+       len = mbedtls_pk_write_key_der(pk, (void *)ctx->start, end - ctx->start);
+       if (len < 0)
+               return len;
+
+       ctx->p -= len;
+
+       /* Convert EC key contents to PKCS#8 style */
+       if (mbedtls_pk_get_type(pk) == MBEDTLS_PK_ECKEY) {
+               mbedtls_ecp_group_id grp_id;
+               mbedtls_asn1_buf tag_buf;
+               uint8_t *pkey_start, *pkey_end;
+               size_t seq_len, pkey_len, param_tag_len;
+               uint8_t *p = ctx->p;
+               uint8_t *_end = end;
+               uint8_t *_start;
+               int version;
+
+               ret = mbedtls_asn1_get_tag(&p, end, &seq_len, SEQUENCE_TAG);
+               if (ret < 0)
+                       return ret;
+
+               _start = p;
+               _end = p + seq_len;
+               ret = mbedtls_asn1_get_int(&p, _end, &version);
+               if (ret < 0)
+                       return ret;
+
+               /* private key */
+               ret = mbedtls_asn1_get_tag(&p, _end, &pkey_len, MBEDTLS_ASN1_OCTET_STRING);
+               if (ret < 0)
+                       return ret;
+               pkey_start = p;
+               p += pkey_len;
+               pkey_end = p;
+
+               /* parameters */
+               ret = mbedtls_asn1_get_tag(&p, _end, &param_len, CONTEXT_TAG(0));
+               if (ret < 0)
+                       return ret;
+
+               param = memcpy(buf, p, param_len);
+               p += param_len;
+
+               /* overwrite parameters */
+               param_tag_len = p - pkey_end;
+               ctx->p += param_tag_len;
+               _start += param_tag_len;
+               memmove(ctx->p, ctx->p - param_tag_len, p - ctx->p);
+
+               /* replace sequence tag */
+               ctx->p = _start;
+               uc_p12_add_sequence(ctx, end);
+
+               /* check for Curve25519 or Curve448 */
+               tag_buf = (mbedtls_asn1_buf){
+                       .p = (uint8_t *)buf,
+                       .len = param_len,
+               };
+               tag_buf.tag = *tag_buf.p;
+               ret = mbedtls_asn1_get_tag(&tag_buf.p, tag_buf.p + param_len, &tag_buf.len, tag_buf.tag);
+               if (ret < 0)
+                       return ret;
+
+               oid = MBEDTLS_OID_EC_ALG_UNRESTRICTED;
+               oid_len = MBEDTLS_OID_SIZE(MBEDTLS_OID_EC_ALG_UNRESTRICTED);
+
+#ifdef MBEDTLS_LEGACY
+               (void)pkey_start;
+               (void)grp_id;
+#else
+               ret = mbedtls_oid_get_ec_grp_algid(&tag_buf, &grp_id);
+               if (!ret && (grp_id == MBEDTLS_ECP_DP_CURVE25519 ||
+                            grp_id == MBEDTLS_ECP_DP_CURVE448)) {
+                       ctx->p = end - pkey_len;
+                       memmove(ctx->p, pkey_start, pkey_len);
+                       uc_p12_add_tag(ctx, end, MBEDTLS_ASN1_OCTET_STRING);
+               }
+#endif
+       } else {
+               mbedtls_oid_get_oid_by_pk_alg(mbedtls_pk_get_type(pk), &oid, &oid_len);
+       }
+
+       uc_p12_add_tag(ctx, end, MBEDTLS_ASN1_OCTET_STRING);
+
+       /* KeyBag */
+       if (param_len) {
+               CTX_ADD(ctx, param_len);
+               memcpy(ctx->p, param, param_len);
+       }
+       uc_p12_add_algo(ctx, oid, oid_len, param_len);
+       mbedtls_asn1_write_int(&ctx->p, ctx->start, 0);
+       uc_p12_add_sequence(ctx, end);
+
+       ret = uc_p12_encrypt(ctx, end);
+       if (ret < 0)
+               return ret;
+
+       ret = uc_p12_add_enc_params(ctx);
+       if (ret < 0)
+               return ret;
+
+       uc_p12_add_sequence(ctx, end);
+
+       uc_p12_add_bag(ctx, end, bag_end, OID_TAG(PKCS12_SHROUDED_KEY_BAG));
+
+       return 0;
+}
+
+static int
+uc_p12_add_authsafe(struct pkcs12_ctx *ctx, uc_value_t *arg)
+{
+       uc_value_t *extra;
+       uint8_t *end = ctx->p;
+       size_t len;
+       int ret;
+
+       /* authSafe contents */
+       extra = ucv_object_get(arg, "extra", NULL);
+       if (extra) {
+               size_t len;
+
+               if (ucv_type(extra) != UC_ARRAY)
+                       return -1;
+
+               len = ucv_array_length(extra);
+               for (size_t i = 0; i < len; i++) {
+                       ret = uc_p12_add_cert(ctx, ucv_array_get(extra, i), true);
+                       if (ret < 0)
+                           return ret;
+               }
+       }
+
+       ret = uc_p12_add_key(ctx, ucv_object_get(arg, "key", NULL));
+       if (ret < 0)
+           return ret;
+
+       ret = uc_p12_add_cert(ctx, ucv_object_get(arg, "cert", NULL), false);
+       if (ret < 0)
+           return ret;
+
+       /* encrypted */
+       uc_p12_add_sequence(ctx, end);
+
+       ret = uc_p12_encrypt(ctx, end);
+       if (ret < 0)
+                return ret;
+
+       uc_p12_add_tag(ctx, end, CONTEXT_TAG(0));
+
+       ret = uc_p12_add_enc_params(ctx);
+       if (ret < 0)
+               return ret;
+
+       mbedtls_asn1_write_oid(&ctx->p, ctx->start, OID_TAG(PKCS7_DATA));
+       uc_p12_add_sequence(ctx, end);
+
+       mbedtls_asn1_write_int(&ctx->p, ctx->start, 0);
+       uc_p12_add_sequence(ctx, end);
+       uc_p12_add_tag(ctx, end, CONTEXT_TAG(0));
+       mbedtls_asn1_write_oid(&ctx->p, ctx->start, OID_TAG(PKCS7_ENCRYPTED_DATA));
+       uc_p12_add_sequence(ctx, end);
+
+       /* authSafe contents */
+       uc_p12_add_sequence(ctx, end);
+
+       /* authSafe header */
+       len = end - ctx->p;
+       uc_p12_add_tag(ctx, end, MBEDTLS_ASN1_OCTET_STRING);
+       uc_p12_add_tag(ctx, end, CONTEXT_TAG(0));
+       mbedtls_asn1_write_oid(&ctx->p, ctx->start, OID_TAG(PKCS7_DATA));
+       uc_p12_add_sequence(ctx, end);
+
+       return len;
+}
+
+static void *
+uc_p12_add_mac_digest_info(struct pkcs12_ctx *ctx)
+{
+       uint8_t *end = ctx->p;
+       size_t len = 20;
+
+       ctx->p -= len;
+       uc_p12_add_tag(ctx, end, MBEDTLS_ASN1_OCTET_STRING);
+       uc_p12_add_algo(ctx, OID_TAG(DIGEST_ALG_SHA1), 0);
+       uc_p12_add_sequence(ctx, end);
+
+       return end - len;
+}
+
+uc_value_t *uc_generate_pkcs12(uc_vm_t *vm, size_t nargs)
+{
+       uc_value_t *arg = uc_fn_arg(0), *pwd_arg;
+       mbedtls_md_context_t hmac;
+       uint8_t *end = (uint8_t *)&buf[sizeof(buf)];
+       struct pkcs12_ctx ctx = {
+               .start = (uint8_t *)&buf[sizeof(buf) / 2],
+               .p = end,
+       };
+       uint8_t *hash, *data;
+       uint8_t key[20], *salt;
+       size_t salt_len = 8;
+       int data_len;
+       uc_value_t *ret = NULL;
+       const char *passwd;
+
+       if (ucv_type(arg) != UC_OBJECT)
+               INVALID_ARG();
+
+       ctx.legacy = ucv_is_truish(ucv_object_get(arg, "legacy", NULL));
+
+       mbedtls_md_init(&hmac);
+       pwd_arg = ucv_object_get(arg, "password", NULL);
+       passwd = ucv_string_get(pwd_arg);
+       if (!passwd)
+               INVALID_ARG();
+
+       /* password is expected to be a UTF-16 string */
+       ctx.password = passwd;
+       ctx.pwd_len = 2 * strlen(passwd) + 2;
+       ctx.pwd = malloc(ctx.pwd_len);
+       for (size_t i = 0; i < ctx.pwd_len; i += 2) {
+               ctx.pwd[i] = 0;
+               ctx.pwd[i + 1] = passwd[i / 2];
+       }
+
+       /* MacData */
+       mbedtls_asn1_write_int(&ctx.p, ctx.start, NUM_ITER);
+
+       ctx.p -= salt_len;
+       salt = ctx.p;
+       random_cb(NULL, salt, salt_len);
+       uc_p12_add_tag(&ctx, salt + salt_len, MBEDTLS_ASN1_OCTET_STRING);
+
+       hash = uc_p12_add_mac_digest_info(&ctx);
+       uc_p12_add_sequence(&ctx, end);
+
+       data = ctx.p;
+       data_len = uc_p12_add_authsafe(&ctx, arg);
+       if (C(data_len) < 0)
+           goto out;
+       data -= data_len;
+
+       mbedtls_asn1_write_int(&ctx.p, ctx.start, 3);
+       uc_p12_add_sequence(&ctx, end);
+
+       if (C(mbedtls_pkcs12_derivation(key, sizeof(key), ctx.pwd, ctx.pwd_len,
+                                       salt, salt_len, MBEDTLS_MD_SHA1,
+                                       MBEDTLS_PKCS12_DERIVE_MAC_KEY, NUM_ITER)))
+               goto out;
+
+       if (C(mbedtls_md_setup(&hmac, mbedtls_md_info_from_type(MBEDTLS_MD_SHA1), 1)))
+               goto out;
+       if (C(mbedtls_md_hmac_starts(&hmac, key, sizeof(key))))
+               goto out;
+       if (C(mbedtls_md_hmac_update(&hmac, data, data_len)))
+               goto out;
+       if (C(mbedtls_md_hmac_finish(&hmac, hash)))
+               goto out;
+
+       ret = ucv_string_new_length((char *)ctx.p, end - ctx.p);
+
+out:
+       free(ctx.pwd);
+       mbedtls_md_free(&hmac);
+       return ret;
+}
diff --git a/package/utils/ucode-mod-pkgen/src/ucode.c b/package/utils/ucode-mod-pkgen/src/ucode.c
new file mode 100644 (file)
index 0000000..cb5569b
--- /dev/null
@@ -0,0 +1,598 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2024 Felix Fietkau <nbd@nbd.name>
+ */
+#include <sys/types.h>
+#include <sys/random.h>
+
+#include <stdint.h>
+#include <limits.h>
+#include <errno.h>
+
+#include <mbedtls/entropy.h>
+#include <mbedtls/x509_crt.h>
+#include <mbedtls/ecp.h>
+#include <mbedtls/rsa.h>
+
+#include <ucode/module.h>
+
+#include "pk.h"
+
+/* mbedtls < 3.x compat */
+#ifdef MBEDTLS_LEGACY
+#define mbedtls_pk_parse_key(pk, key, keylen, passwd, passwdlen, random, random_ctx) \
+       mbedtls_pk_parse_key(pk, key, keylen, passwd, passwdlen)
+#endif
+
+static uc_resource_type_t *uc_pk_type, *uc_crt_type;
+static uc_value_t *registry;
+char buf[32 * 1024];
+int mbedtls_errno;
+
+struct uc_cert_wr {
+       mbedtls_x509write_cert crt; /* must be first */
+       mbedtls_mpi mpi;
+       unsigned int reg;
+};
+
+static unsigned int uc_reg_add(uc_value_t *val)
+{
+       size_t i = 0;
+
+       while (ucv_array_get(registry, i))
+               i++;
+
+       ucv_array_set(registry, i, ucv_get(val));
+
+       return i;
+}
+
+int random_cb(void *ctx, unsigned char *out, size_t len)
+{
+#ifdef linux
+       if (getrandom(out, len, 0) != (ssize_t) len)
+               return MBEDTLS_ERR_ENTROPY_SOURCE_FAILED;
+#else
+       static FILE *f;
+
+       if (!f)
+               f = fopen("/dev/urandom", "r");
+       if (fread(out, len, 1, f) != 1)
+               return MBEDTLS_ERR_ENTROPY_SOURCE_FAILED;
+#endif
+
+       return 0;
+}
+
+int64_t get_int_arg(uc_value_t *obj, const char *key, int64_t defval)
+{
+       uc_value_t *uval = ucv_object_get(obj, key, NULL);
+       int64_t val;
+
+       if (!uval)
+               return defval;
+
+       val = ucv_int64_get(uval);
+       if (errno || val < 0 || val > INT_MAX)
+               return INT_MIN;
+
+       return val ? val : defval;
+}
+
+static int
+gen_rsa_key(mbedtls_pk_context *pk, uc_value_t *arg)
+{
+       int64_t key_size, exp;
+
+       key_size = get_int_arg(arg, "size", 2048);
+       exp = get_int_arg(arg, "exponent", 65537);
+       if (key_size < 0 || exp < 0)
+               return -1;
+
+       return mbedtls_rsa_gen_key(mbedtls_pk_rsa(*pk), random_cb, NULL, key_size, exp);
+}
+
+static int
+gen_ec_key(mbedtls_pk_context *pk, uc_value_t *arg)
+{
+       mbedtls_ecp_group_id curve;
+       const char *c_name;
+       uc_value_t *c_arg;
+
+       c_arg = ucv_object_get(arg, "curve", NULL);
+       if (c_arg && ucv_type(c_arg) != UC_STRING)
+               return -1;
+
+       c_name = ucv_string_get(c_arg);
+       if (!c_name)
+               curve = MBEDTLS_ECP_DP_SECP256R1;
+       else {
+               const mbedtls_ecp_curve_info *curve_info;
+               curve_info = mbedtls_ecp_curve_info_from_name(c_name);
+               if (!curve_info)
+                       return MBEDTLS_ERR_PK_UNKNOWN_NAMED_CURVE;
+
+               curve = curve_info->grp_id;
+       }
+
+       return mbedtls_ecp_gen_key(curve, mbedtls_pk_ec(*pk), random_cb, NULL);
+}
+
+static void free_pk(void *pk)
+{
+       if (!pk)
+               return;
+
+       mbedtls_pk_free(pk);
+       free(pk);
+}
+
+static void free_crt(void *ptr)
+{
+       struct uc_cert_wr *crt = ptr;
+
+       if (!crt)
+               return;
+
+       mbedtls_x509write_crt_free(&crt->crt);
+       mbedtls_mpi_free(&crt->mpi);
+       ucv_array_set(registry, crt->reg, NULL);
+       free(crt);
+}
+
+static uc_value_t *
+uc_generate_key(uc_vm_t *vm, size_t nargs)
+{
+       uc_value_t *cur, *arg = uc_fn_arg(0);
+       mbedtls_pk_type_t pk_type;
+       mbedtls_pk_context *pk;
+       const char *type;
+       int ret;
+
+       if (ucv_type(arg) != UC_OBJECT)
+               INVALID_ARG();
+
+       cur = ucv_object_get(arg, "type", NULL);
+       type = ucv_string_get(cur);
+       if (!type)
+               INVALID_ARG();
+
+       if (!strcmp(type, "rsa"))
+               pk_type = MBEDTLS_PK_RSA;
+       else if (!strcmp(type, "ec"))
+               pk_type = MBEDTLS_PK_ECKEY;
+       else
+               INVALID_ARG();
+
+       pk = calloc(1, sizeof(*pk));
+       mbedtls_pk_init(pk);
+       mbedtls_pk_setup(pk, mbedtls_pk_info_from_type(pk_type));
+       switch (pk_type) {
+       case MBEDTLS_PK_RSA:
+               ret = C(gen_rsa_key(pk, arg));
+               break;
+       case MBEDTLS_PK_ECKEY:
+               ret = C(gen_ec_key(pk, arg));
+               break;
+       default:
+               ret = -1;
+       }
+
+       if (ret) {
+               free_pk(pk);
+               return NULL;
+       }
+
+       return uc_resource_new(uc_pk_type, pk);
+}
+
+static uc_value_t *
+uc_load_key(uc_vm_t *vm, size_t nargs)
+{
+       uc_value_t *keystr = uc_fn_arg(0);
+       uc_value_t *pub = uc_fn_arg(1);
+       uc_value_t *passwd = uc_fn_arg(2);
+       mbedtls_pk_context *pk;
+       int ret;
+
+       if (ucv_type(keystr) != UC_STRING ||
+           (pub && ucv_type(pub) != UC_BOOLEAN) ||
+           (passwd && ucv_type(passwd) != UC_STRING))
+               INVALID_ARG();
+
+       pk = calloc(1, sizeof(*pk));
+       mbedtls_pk_init(pk);
+       if (ucv_is_truish(pub))
+               ret = C(mbedtls_pk_parse_public_key(pk, (const uint8_t *)ucv_string_get(keystr),
+                                                   ucv_string_length(keystr) + 1));
+       else
+               ret = C(mbedtls_pk_parse_key(pk, (const uint8_t *)ucv_string_get(keystr),
+                                            ucv_string_length(keystr) + 1,
+                                            (const uint8_t *)ucv_string_get(passwd),
+                                            ucv_string_length(passwd) + 1,
+                                            random_cb, NULL));
+       if (ret) {
+               free_pk(pk);
+               return NULL;
+       }
+
+       return uc_resource_new(uc_pk_type, pk);
+}
+
+static void
+uc_cert_info_add(uc_value_t *info, const char *name, int len)
+{
+       uc_value_t *val;
+
+       if (len < 0)
+               return;
+
+       val = ucv_string_new_length(buf, len);
+       ucv_object_add(info, name, ucv_get(val));
+}
+
+static void
+uc_cert_info_add_name(uc_value_t *info, const char *name, mbedtls_x509_name *dn)
+{
+       int len;
+
+       len = mbedtls_x509_dn_gets(buf, sizeof(buf), dn);
+       uc_cert_info_add(info, name, len);
+}
+
+static void
+uc_cert_info_add_time(uc_value_t *info, const char *name, mbedtls_x509_time *t)
+{
+       int len;
+
+       len = snprintf(buf, sizeof(buf), "%04d%02d%02d%02d%02d%02d",
+                      t->year, t->mon, t->day, t->hour, t->min, t->sec);
+       uc_cert_info_add(info, name, len);
+}
+
+static uc_value_t *
+uc_cert_info(uc_vm_t *vm, size_t nargs)
+{
+       uc_value_t *arg = uc_fn_arg(0);
+       mbedtls_x509_crt crt, *cur;
+       uc_value_t *ret = NULL;
+
+       if (ucv_type(arg) != UC_STRING)
+               return NULL;
+
+       mbedtls_x509_crt_init(&crt);
+       if (C(mbedtls_x509_crt_parse(&crt, (const void *)ucv_string_get(arg), ucv_string_length(arg) + 1)) < 0)
+               goto out;
+
+       ret = ucv_array_new(vm);
+       for (cur = &crt; cur && cur->version != 0; cur = cur->next) {
+               uc_value_t *info = ucv_object_new(vm);
+               int len;
+
+               ucv_array_push(ret, ucv_get(info));
+               ucv_object_add(info, "version", ucv_int64_new(cur->version));
+
+               uc_cert_info_add_name(info, "issuer", &cur->issuer);
+               uc_cert_info_add_name(info, "subject", &cur->issuer);
+               uc_cert_info_add_time(info, "valid_from", &cur->valid_from);
+               uc_cert_info_add_time(info, "valid_to", &cur->valid_to);
+
+               len = mbedtls_x509_serial_gets(buf, sizeof(buf), &cur->serial);
+               uc_cert_info_add(info, "serial", len);
+       }
+
+out:
+       mbedtls_x509_crt_free(&crt);
+       return ret;
+}
+
+static uc_value_t *
+uc_pk_pem(uc_vm_t *vm, size_t nargs)
+{
+       mbedtls_pk_context *pk = uc_fn_thisval("mbedtls.pk");
+       uc_value_t *pub = uc_fn_arg(0);
+
+       if (!pk)
+               return NULL;
+
+       if (ucv_is_truish(pub))
+               CHECK(mbedtls_pk_write_pubkey_pem(pk, (void *)buf, sizeof(buf)));
+       else
+               CHECK(mbedtls_pk_write_key_pem(pk, (void *)buf, sizeof(buf)));
+
+       return ucv_string_new(buf);
+}
+
+static uc_value_t *
+uc_pk_der(uc_vm_t *vm, size_t nargs)
+{
+       mbedtls_pk_context *pk = uc_fn_thisval("mbedtls.pk");
+       uc_value_t *pub = uc_fn_arg(0);
+       int len;
+
+       if (!pk)
+               return NULL;
+
+       if (ucv_is_truish(pub))
+               len = mbedtls_pk_write_pubkey_der(pk, (void *)buf, sizeof(buf));
+       else
+               len = mbedtls_pk_write_key_der(pk, (void *)buf, sizeof(buf));
+       if (len < 0)
+               CHECK(len);
+
+       return ucv_string_new_length(buf + sizeof(buf) - len, len);
+}
+
+static uc_value_t *
+uc_crt_pem(uc_vm_t *vm, size_t nargs)
+{
+       mbedtls_x509write_cert *crt = uc_fn_thisval("mbedtls.crt");
+       if (!crt)
+               return NULL;
+
+       CHECK(mbedtls_x509write_crt_pem(crt, (void *)buf, sizeof(buf), random_cb, NULL));
+
+       return ucv_string_new(buf);
+}
+
+static uc_value_t *
+uc_crt_der(uc_vm_t *vm, size_t nargs)
+{
+       mbedtls_x509write_cert *crt = uc_fn_thisval("mbedtls.crt");
+       int len;
+
+       if (!crt)
+               return NULL;
+
+       len = mbedtls_x509write_crt_der(crt, (void *)buf, sizeof(buf), random_cb, NULL);
+       if (len < 0)
+               CHECK(len);
+
+       return ucv_string_new_length(buf, len);
+}
+
+static int
+uc_cert_set_validity(mbedtls_x509write_cert *crt, uc_value_t *arg)
+{
+       uc_value_t *from = ucv_array_get(arg, 0);
+       uc_value_t *to = ucv_array_get(arg, 1);
+
+       if (ucv_type(from) != UC_STRING || ucv_type(to) != UC_STRING)
+               return -1;
+
+       return mbedtls_x509write_crt_set_validity(crt, ucv_string_get(from), ucv_string_get(to));
+}
+
+static int
+uc_cert_init(mbedtls_x509write_cert *crt, mbedtls_mpi *mpi, uc_value_t *reg, uc_value_t *arg)
+{
+       uc_value_t *cur;
+       int64_t serial;
+       int path_len;
+       int version;
+       bool ca;
+
+       mbedtls_mpi_init(mpi);
+       mbedtls_x509write_crt_init(crt);
+       mbedtls_x509write_crt_set_md_alg(crt, MBEDTLS_MD_SHA256);
+
+       ca = ucv_is_truish(ucv_object_get(arg, "ca", NULL));
+       path_len = get_int_arg(arg, "max_pathlen", ca ? -1 : 0);
+       if (path_len < -1)
+               return -1;
+
+       version = get_int_arg(arg, "version", 3);
+       if (version < 0 || version > 3)
+               return -1;
+
+       serial = get_int_arg(arg, "serial", 1);
+       if (serial < 0)
+               return -1;
+
+       mbedtls_mpi_lset(mpi, serial);
+       mbedtls_x509write_crt_set_serial(crt, mpi);
+       mbedtls_x509write_crt_set_version(crt, version - 1);
+       CHECK_INT(mbedtls_x509write_crt_set_basic_constraints(crt, ca, path_len));
+
+       cur = ucv_object_get(arg, "subject_name", NULL);
+       if (ucv_type(cur) == UC_STRING)
+               CHECK_INT(mbedtls_x509write_crt_set_subject_name(crt, ucv_string_get(cur)));
+       else
+               return -1;
+       cur = ucv_object_get(arg, "subject_key", NULL);
+       if (cur) {
+               mbedtls_pk_context *key = ucv_resource_data(cur, "mbedtls.pk");
+               if (!key)
+                       return -1;
+
+               ucv_array_set(reg, 0, ucv_get(cur));
+               mbedtls_x509write_crt_set_subject_key(crt, key);
+               mbedtls_x509write_crt_set_subject_key_identifier(crt);
+       } else
+               return -1;
+
+       cur = ucv_object_get(arg, "issuer_name", NULL);
+       if (ucv_type(cur) == UC_STRING)
+               CHECK_INT(mbedtls_x509write_crt_set_issuer_name(crt, ucv_string_get(cur)));
+       else
+               return -1;
+       cur = ucv_object_get(arg, "issuer_key", NULL);
+       if (cur) {
+               mbedtls_pk_context *key = ucv_resource_data(cur, "mbedtls.pk");
+               if (!key)
+                       return -1;
+
+               ucv_array_set(reg, 1, ucv_get(cur));
+               mbedtls_x509write_crt_set_issuer_key(crt, key);
+               mbedtls_x509write_crt_set_authority_key_identifier(crt);
+       } else
+               return -1;
+
+       cur = ucv_object_get(arg, "validity", NULL);
+       if (ucv_type(cur) != UC_ARRAY || ucv_array_length(cur) != 2)
+               return -1;
+       if (uc_cert_set_validity(crt, cur))
+               return -1;
+
+       cur = ucv_object_get(arg, "key_usage", NULL);
+       if (ucv_type(cur) == UC_ARRAY) {
+               static const struct {
+                       const char *name;
+                       uint8_t val;
+               } key_flags[] = {
+                       { "digital_signature", MBEDTLS_X509_KU_DIGITAL_SIGNATURE },
+                       { "non_repudiation", MBEDTLS_X509_KU_NON_REPUDIATION },
+                       { "key_encipherment", MBEDTLS_X509_KU_KEY_ENCIPHERMENT },
+                       { "data_encipherment", MBEDTLS_X509_KU_DATA_ENCIPHERMENT },
+                       { "key_agreement", MBEDTLS_X509_KU_KEY_AGREEMENT },
+                       { "key_cert_sign", MBEDTLS_X509_KU_KEY_CERT_SIGN },
+                       { "crl_sign", MBEDTLS_X509_KU_CRL_SIGN },
+               };
+               uint8_t key_usage = 0;
+               size_t len = ucv_array_length(cur);
+
+               for (size_t i = 0; i < len; i++) {
+                       uc_value_t *val = ucv_array_get(cur, i);
+                       const char *str;
+                       size_t k;
+
+                       str = ucv_string_get(val);
+                       if (!str)
+                               return -1;
+
+                       for (k = 0; k < ARRAY_SIZE(key_flags); k++)
+                               if (!strcmp(str, key_flags[k].name))
+                                       break;
+                       if (k == ARRAY_SIZE(key_flags))
+                               return -1;
+
+                       key_usage |= key_flags[k].val;
+               }
+               CHECK_INT(mbedtls_x509write_crt_set_key_usage(crt, key_usage));
+       } else if (cur)
+               return -1;
+
+#ifndef MBEDTLS_LEGACY
+       cur = ucv_object_get(arg, "ext_key_usage", NULL);
+       if (ucv_type(cur) == UC_ARRAY && ucv_array_length(cur)) {
+               static const struct {
+                       const char *name;
+                       struct mbedtls_asn1_buf val;
+               } key_flags[] = {
+#define __oid(name, val)                                       \
+       {                                                       \
+               name,                                           \
+               {                                               \
+                       .tag = MBEDTLS_ASN1_OID,                \
+                       .len = sizeof(MBEDTLS_OID_##val),       \
+                       .p = (uint8_t *)MBEDTLS_OID_##val,      \
+               }                                               \
+       }
+                       __oid("server_auth", SERVER_AUTH),
+                       __oid("client_auth", CLIENT_AUTH),
+                       __oid("code_signing", CODE_SIGNING),
+                       __oid("email_protection", EMAIL_PROTECTION),
+                       __oid("time_stamping", TIME_STAMPING),
+                       __oid("ocsp_signing", OCSP_SIGNING),
+                       __oid("any", ANY_EXTENDED_KEY_USAGE)
+               };
+               struct mbedtls_asn1_sequence *elem;
+               size_t len = ucv_array_length(cur);
+
+               elem = calloc(len, sizeof(*elem));
+               for (size_t i = 0; i < len; i++) {
+                       uc_value_t *val = ucv_array_get(cur, i);
+                       const char *str;
+                       size_t k;
+
+                       str = ucv_string_get(val);
+                       if (!str)
+                               return -1;
+
+                       for (k = 0; k < ARRAY_SIZE(key_flags); k++)
+                               if (!strcmp(str, key_flags[k].name))
+                                       break;
+
+                       if (k == ARRAY_SIZE(key_flags)) {
+                               free(elem);
+                               return -1;
+                       }
+                       elem[i].buf = key_flags[k].val;
+                       if (i + 1 < len)
+                               elem[i].next = &elem[i + 1];
+               }
+
+               CHECK_INT(mbedtls_x509write_crt_set_ext_key_usage(crt, elem));
+       } else if (cur)
+               return -1;
+#endif
+
+       return 0;
+}
+
+static uc_value_t *
+uc_generate_cert(uc_vm_t *vm, size_t nargs)
+{
+       struct uc_cert_wr *crt;
+       uc_value_t *arg = uc_fn_arg(0);
+       uc_value_t *reg;
+
+       if (ucv_type(arg) != UC_OBJECT)
+               return NULL;
+
+       reg = ucv_array_new(vm);
+       crt = calloc(1, sizeof(*crt));
+       if (C(uc_cert_init(&crt->crt, &crt->mpi, reg, arg))) {
+               free(crt);
+               return NULL;
+       }
+
+       crt->reg = uc_reg_add(reg);
+
+       return uc_resource_new(uc_crt_type, crt);
+}
+
+static uc_value_t *
+uc_mbedtls_error(uc_vm_t *vm, size_t nargs)
+{
+       mbedtls_strerror(mbedtls_errno, buf, sizeof(buf));
+
+       return ucv_string_new(buf);
+}
+
+static uc_value_t *
+uc_mbedtls_errno(uc_vm_t *vm, size_t nargs)
+{
+       return ucv_int64_new(mbedtls_errno);
+}
+
+
+static const uc_function_list_t pk_fns[] = {
+       { "pem", uc_pk_pem },
+       { "der", uc_pk_der },
+};
+
+static const uc_function_list_t crt_fns[] = {
+       { "pem", uc_crt_pem },
+       { "der", uc_crt_der },
+};
+
+static const uc_function_list_t global_fns[] = {
+       { "load_key", uc_load_key },
+       { "cert_info", uc_cert_info },
+       { "generate_key", uc_generate_key },
+       { "generate_cert", uc_generate_cert },
+       { "generate_pkcs12", uc_generate_pkcs12 },
+       { "errno", uc_mbedtls_errno },
+       { "error", uc_mbedtls_error },
+};
+
+void uc_module_init(uc_vm_t *vm, uc_value_t *scope)
+{
+       uc_pk_type = uc_type_declare(vm, "mbedtls.pk", pk_fns, free_pk);
+       uc_crt_type = uc_type_declare(vm, "mbedtls.crt", crt_fns, free_crt);
+       uc_function_list_register(scope, global_fns);
+
+       registry = ucv_array_new(vm);
+       uc_vm_registry_set(vm, "pkgen.registry", registry);
+}