Add the STORE module

This STORE module adds the following functionality:

- A function OSSL_STORE_open(), OSSL_STORE_load() and OSSL_STORE_close()
  that accesses a URI and helps loading the supported objects (PKEYs,
  CERTs and CRLs for the moment) from it.
- An opaque type OSSL_STORE_INFO that holds information on each loaded
  object.
- A few functions to retrieve desired data from a OSSL_STORE_INFO
  reference.
- Functions to register and unregister loaders for different URI
  schemes.  This enables dynamic addition of loaders from applications
  or from engines.

Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3542)

7 files changed, 840 insertions, 0 deletions

diff --git a/crypto/store/build.info b/crypto/store/build.info
new file mode 100644
index 0000000000..4b6af29817
--- /dev/null
+++ b/crypto/store/build.info
@@ -0,0 +1,3 @@
+LIBS=../../libcrypto
+SOURCE[../../libcrypto]=\
+        store_err.c store_init.c store_lib.c store_register.c store_strings.c
diff --git a/crypto/store/store_err.c b/crypto/store/store_err.c
new file mode 100644
index 0000000000..3f5069abf5
--- /dev/null
+++ b/crypto/store/store_err.c
@@ -0,0 +1,83 @@
+/*
+ * Generated by util/mkerr.pl DO NOT EDIT
+ * Copyright 1995-2017 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the OpenSSL license (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+#include <openssl/err.h>
+#include <openssl/storeerr.h>
+
+#ifndef OPENSSL_NO_ERR
+
+static const ERR_STRING_DATA OSSL_STORE_str_functs[] = {
+    {ERR_PACK(ERR_LIB_OSSL_STORE, OSSL_STORE_F_OSSL_STORE_GET0_LOADER_INT, 0),
+     "ossl_store_get0_loader_int"},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, OSSL_STORE_F_OSSL_STORE_INFO_GET1_CERT, 0),
+     "OSSL_STORE_INFO_get1_CERT"},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, OSSL_STORE_F_OSSL_STORE_INFO_GET1_CRL, 0),
+     "OSSL_STORE_INFO_get1_CRL"},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, OSSL_STORE_F_OSSL_STORE_INFO_GET1_NAME, 0),
+     "OSSL_STORE_INFO_get1_NAME"},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, OSSL_STORE_F_OSSL_STORE_INFO_GET1_NAME_DESCRIPTION, 0),
+     "OSSL_STORE_INFO_get1_NAME_description"},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, OSSL_STORE_F_OSSL_STORE_INFO_GET1_PARAMS, 0),
+     "OSSL_STORE_INFO_get1_PARAMS"},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, OSSL_STORE_F_OSSL_STORE_INFO_GET1_PKEY, 0),
+     "OSSL_STORE_INFO_get1_PKEY"},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, OSSL_STORE_F_OSSL_STORE_INFO_NEW_CERT, 0),
+     "OSSL_STORE_INFO_new_CERT"},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, OSSL_STORE_F_OSSL_STORE_INFO_NEW_CRL, 0),
+     "OSSL_STORE_INFO_new_CRL"},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, OSSL_STORE_F_OSSL_STORE_INFO_NEW_NAME, 0),
+     "OSSL_STORE_INFO_new_NAME"},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, OSSL_STORE_F_OSSL_STORE_INFO_NEW_PARAMS, 0),
+     "OSSL_STORE_INFO_new_PARAMS"},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, OSSL_STORE_F_OSSL_STORE_INFO_NEW_PKEY, 0),
+     "OSSL_STORE_INFO_new_PKEY"},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, OSSL_STORE_F_OSSL_STORE_INFO_SET0_NAME_DESCRIPTION, 0),
+     "OSSL_STORE_INFO_set0_NAME_description"},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, OSSL_STORE_F_OSSL_STORE_INIT_ONCE, 0),
+     "ossl_store_init_once"},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, OSSL_STORE_F_OSSL_STORE_LOADER_NEW, 0),
+     "OSSL_STORE_LOADER_new"},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, OSSL_STORE_F_OSSL_STORE_OPEN, 0),
+     "OSSL_STORE_open"},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, OSSL_STORE_F_OSSL_STORE_OPEN_INT, 0), ""},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, OSSL_STORE_F_OSSL_STORE_REGISTER_LOADER_INT, 0),
+     "ossl_store_register_loader_int"},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, OSSL_STORE_F_OSSL_STORE_UNREGISTER_LOADER_INT, 0),
+     "ossl_store_unregister_loader_int"},
+    {0, NULL}
+};
+
+static const ERR_STRING_DATA OSSL_STORE_str_reasons[] = {
+    {ERR_PACK(ERR_LIB_OSSL_STORE, 0, OSSL_STORE_R_INVALID_SCHEME),
+    "invalid scheme"},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, 0, OSSL_STORE_R_NOT_A_CERTIFICATE),
+    "not a certificate"},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, 0, OSSL_STORE_R_NOT_A_CRL), "not a crl"},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, 0, OSSL_STORE_R_NOT_A_KEY), "not a key"},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, 0, OSSL_STORE_R_NOT_A_NAME), "not a name"},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, 0, OSSL_STORE_R_NOT_PARAMETERS),
+    "not parameters"},
+    {ERR_PACK(ERR_LIB_OSSL_STORE, 0, OSSL_STORE_R_UNREGISTERED_SCHEME),
+    "unregistered scheme"},
+    {0, NULL}
+};
+
+#endif
+
+int ERR_load_OSSL_STORE_strings(void)
+{
+#ifndef OPENSSL_NO_ERR
+    if (ERR_func_error_string(OSSL_STORE_str_functs[0].error) == NULL) {
+        ERR_load_strings_const(OSSL_STORE_str_functs);
+        ERR_load_strings_const(OSSL_STORE_str_reasons);
+    }
+#endif
+    return 1;
+}
diff --git a/crypto/store/store_init.c b/crypto/store/store_init.c
new file mode 100644
index 0000000000..90d5436634
--- /dev/null
+++ b/crypto/store/store_init.c
@@ -0,0 +1,32 @@
+/*
+ * Copyright 2016-2017 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the OpenSSL license (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+#include <openssl/err.h>
+#include "internal/store.h"
+#include "store_locl.h"
+
+static CRYPTO_ONCE store_init = CRYPTO_ONCE_STATIC_INIT;
+DEFINE_RUN_ONCE_STATIC(do_store_init)
+{
+    return OPENSSL_init_crypto(0, NULL);
+}
+
+int ossl_store_init_once()
+{
+    if (!RUN_ONCE(&store_init, do_store_init)) {
+        OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_INIT_ONCE, ERR_R_MALLOC_FAILURE);
+        return 0;
+    }
+    return 1;
+}
+
+void ossl_store_cleanup_int(void)
+{
+    ossl_store_destroy_loaders_int();
+}
diff --git a/crypto/store/store_lib.c b/crypto/store/store_lib.c
new file mode 100644
index 0000000000..5f07f8ce5f
--- /dev/null
+++ b/crypto/store/store_lib.c
@@ -0,0 +1,366 @@
+/*
+ * Copyright 2016-2017 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the OpenSSL license (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+#include <stdlib.h>
+#include <string.h>
+
+#include <openssl/crypto.h>
+#include <openssl/err.h>
+#include <openssl/store.h>
+#include "internal/thread_once.h"
+#include "store_locl.h"
+
+struct ossl_store_ctx_st {
+    const OSSL_STORE_LOADER *loader;
+    OSSL_STORE_LOADER_CTX *loader_ctx;
+    const UI_METHOD *ui_method;
+    void *ui_data;
+    OSSL_STORE_post_process_info_fn post_process;
+    void *post_process_data;
+};
+
+OSSL_STORE_CTX *OSSL_STORE_open(const char *uri, const UI_METHOD *ui_method,
+                                void *ui_data,
+                                OSSL_STORE_post_process_info_fn post_process,
+                                void *post_process_data)
+{
+    const OSSL_STORE_LOADER *loader;
+    OSSL_STORE_LOADER_CTX *loader_ctx = NULL;
+    OSSL_STORE_CTX *ctx = NULL;
+    char scheme_copy[256], *p;
+
+    OPENSSL_strlcpy(scheme_copy, uri, sizeof(scheme_copy));
+    if ((p = strchr(scheme_copy, ':')) != NULL) {
+        *p = '\0';
+        p = scheme_copy;
+    } else {
+        p = "file";
+    }
+
+    if ((loader = ossl_store_get0_loader_int(p)) == NULL
+        || (loader_ctx = loader->open(loader, uri, ui_method, ui_data)) == NULL)
+        goto done;
+    if ((ctx = OPENSSL_zalloc(sizeof(*ctx))) == NULL) {
+        OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_OPEN, ERR_R_MALLOC_FAILURE);
+        goto done;
+    }
+
+    ctx->loader = loader;
+    ctx->loader_ctx = loader_ctx;
+    loader_ctx = NULL;
+    ctx->ui_method = ui_method;
+    ctx->ui_data = ui_data;
+    ctx->post_process = post_process;
+    ctx->post_process_data = post_process_data;
+
+ done:
+    if (loader_ctx != NULL) {
+        /*
+         * We ignore a returned error because we will return NULL anyway in
+         * this case, so if something goes wrong when closing, that'll simply
+         * just add another entry on the error stack.
+         */
+        (void)loader->close(loader_ctx);
+    }
+    return ctx;
+}
+
+int OSSL_STORE_ctrl(OSSL_STORE_CTX *ctx, int cmd, ...)
+{
+    va_list args;
+    int ret = 0;
+
+    va_start(args, cmd);
+    if (ctx->loader->ctrl != NULL)
+        ret = ctx->loader->ctrl(ctx->loader_ctx, cmd, args);
+    va_end(args);
+
+    return ret;
+}
+
+OSSL_STORE_INFO *OSSL_STORE_load(OSSL_STORE_CTX *ctx)
+{
+    OSSL_STORE_INFO *v = NULL;
+
+ again:
+    v = ctx->loader->load(ctx->loader_ctx, ctx->ui_method, ctx->ui_data);
+
+    if (ctx->post_process != NULL && v != NULL) {
+        v = ctx->post_process(v, ctx->post_process_data);
+
+        /*
+         * By returning NULL, the callback decides that this object should
+         * be ignored.
+         */
+        if (v == NULL)
+            goto again;
+    }
+
+    return v;
+}
+
+int OSSL_STORE_error(OSSL_STORE_CTX *ctx)
+{
+    return ctx->loader->error(ctx->loader_ctx);
+}
+
+int OSSL_STORE_eof(OSSL_STORE_CTX *ctx)
+{
+    return ctx->loader->eof(ctx->loader_ctx);
+}
+
+int OSSL_STORE_close(OSSL_STORE_CTX *ctx)
+{
+    int loader_ret = ctx->loader->close(ctx->loader_ctx);
+
+    OPENSSL_free(ctx);
+    return loader_ret;
+}
+
+/*
+ * Functions to generate OSSL_STORE_INFOs, one function for each type we
+ * support having in them.  Along with each of them, one macro that
+ * can be used to determine what types are supported.
+ *
+ * In all cases, ownership of the object is transfered to the OSSL_STORE_INFO
+ * and will therefore be freed when the OSSL_STORE_INFO is freed.
+ */
+static OSSL_STORE_INFO *store_info_new(int type, void *data)
+{
+    OSSL_STORE_INFO *info = OPENSSL_zalloc(sizeof(*info));
+
+    if (info == NULL)
+        return NULL;
+
+    info->type = type;
+    info->_.data = data;
+    return info;
+}
+
+OSSL_STORE_INFO *OSSL_STORE_INFO_new_NAME(char *name)
+{
+    OSSL_STORE_INFO *info = store_info_new(OSSL_STORE_INFO_NAME, NULL);
+
+    if (info == NULL) {
+        OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_INFO_NEW_NAME,
+                      ERR_R_MALLOC_FAILURE);
+        return NULL;
+    }
+
+    info->_.name.name = name;
+    info->_.name.desc = NULL;
+
+    return info;
+}
+
+int OSSL_STORE_INFO_set0_NAME_description(OSSL_STORE_INFO *info, char *desc)
+{
+    if (info->type != OSSL_STORE_INFO_NAME) {
+        OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_INFO_SET0_NAME_DESCRIPTION,
+                      ERR_R_PASSED_INVALID_ARGUMENT);
+        return 0;
+    }
+
+    info->_.name.desc = desc;
+
+    return 1;
+}
+OSSL_STORE_INFO *OSSL_STORE_INFO_new_PARAMS(EVP_PKEY *params)
+{
+    OSSL_STORE_INFO *info = store_info_new(OSSL_STORE_INFO_PARAMS, params);
+
+    if (info == NULL)
+        OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_INFO_NEW_PARAMS,
+                      ERR_R_MALLOC_FAILURE);
+    return info;
+}
+
+OSSL_STORE_INFO *OSSL_STORE_INFO_new_PKEY(EVP_PKEY *pkey)
+{
+    OSSL_STORE_INFO *info = store_info_new(OSSL_STORE_INFO_PKEY, pkey);
+
+    if (info == NULL)
+        OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_INFO_NEW_PKEY,
+                      ERR_R_MALLOC_FAILURE);
+    return info;
+}
+
+OSSL_STORE_INFO *OSSL_STORE_INFO_new_CERT(X509 *x509)
+{
+    OSSL_STORE_INFO *info = store_info_new(OSSL_STORE_INFO_CERT, x509);
+
+    if (info == NULL)
+        OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_INFO_NEW_CERT,
+                      ERR_R_MALLOC_FAILURE);
+    return info;
+}
+
+OSSL_STORE_INFO *OSSL_STORE_INFO_new_CRL(X509_CRL *crl)
+{
+    OSSL_STORE_INFO *info = store_info_new(OSSL_STORE_INFO_CRL, crl);
+
+    if (info == NULL)
+        OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_INFO_NEW_CRL,
+                      ERR_R_MALLOC_FAILURE);
+    return info;
+}
+
+/*
+ * Functions to try to extract data from a OSSL_STORE_INFO.
+ */
+int OSSL_STORE_INFO_get_type(const OSSL_STORE_INFO *info)
+{
+    return info->type;
+}
+
+const char *OSSL_STORE_INFO_get0_NAME(const OSSL_STORE_INFO *info)
+{
+    if (info->type == OSSL_STORE_INFO_NAME)
+        return info->_.name.name;
+    return NULL;
+}
+
+char *OSSL_STORE_INFO_get1_NAME(const OSSL_STORE_INFO *info)
+{
+    if (info->type == OSSL_STORE_INFO_NAME) {
+        char *ret = OPENSSL_strdup(info->_.name.name);
+
+        if (ret == NULL)
+            OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_INFO_GET1_NAME,
+                          ERR_R_MALLOC_FAILURE);
+        return ret;
+    }
+    OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_INFO_GET1_NAME,
+                  OSSL_STORE_R_NOT_A_NAME);
+    return NULL;
+}
+
+const char *OSSL_STORE_INFO_get0_NAME_description(const OSSL_STORE_INFO *info)
+{
+    if (info->type == OSSL_STORE_INFO_NAME)
+        return info->_.name.desc;
+    return NULL;
+}
+
+char *OSSL_STORE_INFO_get1_NAME_description(const OSSL_STORE_INFO *info)
+{
+    if (info->type == OSSL_STORE_INFO_NAME) {
+        char *ret = OPENSSL_strdup(info->_.name.desc
+                                   ? info->_.name.desc : "");
+
+        if (ret == NULL)
+            OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_INFO_GET1_NAME_DESCRIPTION,
+                     ERR_R_MALLOC_FAILURE);
+        return ret;
+    }
+    OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_INFO_GET1_NAME_DESCRIPTION,
+                  OSSL_STORE_R_NOT_A_NAME);
+    return NULL;
+}
+
+EVP_PKEY *OSSL_STORE_INFO_get0_PARAMS(const OSSL_STORE_INFO *info)
+{
+    if (info->type == OSSL_STORE_INFO_PARAMS)
+        return info->_.params;
+    return NULL;
+}
+
+EVP_PKEY *OSSL_STORE_INFO_get1_PARAMS(const OSSL_STORE_INFO *info)
+{
+    if (info->type == OSSL_STORE_INFO_PARAMS) {
+        EVP_PKEY_up_ref(info->_.params);
+        return info->_.params;
+    }
+    OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_INFO_GET1_PARAMS,
+                  OSSL_STORE_R_NOT_PARAMETERS);
+    return NULL;
+}
+
+EVP_PKEY *OSSL_STORE_INFO_get0_PKEY(const OSSL_STORE_INFO *info)
+{
+    if (info->type == OSSL_STORE_INFO_PKEY)
+        return info->_.pkey;
+    return NULL;
+}
+
+EVP_PKEY *OSSL_STORE_INFO_get1_PKEY(const OSSL_STORE_INFO *info)
+{
+    if (info->type == OSSL_STORE_INFO_PKEY) {
+        EVP_PKEY_up_ref(info->_.pkey);
+        return info->_.pkey;
+    }
+    OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_INFO_GET1_PKEY,
+                  OSSL_STORE_R_NOT_A_KEY);
+    return NULL;
+}
+
+X509 *OSSL_STORE_INFO_get0_CERT(const OSSL_STORE_INFO *info)
+{
+    if (info->type == OSSL_STORE_INFO_CERT)
+        return info->_.x509;
+    return NULL;
+}
+
+X509 *OSSL_STORE_INFO_get1_CERT(const OSSL_STORE_INFO *info)
+{
+    if (info->type == OSSL_STORE_INFO_CERT) {
+        X509_up_ref(info->_.x509);
+        return info->_.x509;
+    }
+    OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_INFO_GET1_CERT,
+                  OSSL_STORE_R_NOT_A_CERTIFICATE);
+    return NULL;
+}
+
+X509_CRL *OSSL_STORE_INFO_get0_CRL(const OSSL_STORE_INFO *info)
+{
+    if (info->type == OSSL_STORE_INFO_CRL)
+        return info->_.crl;
+    return NULL;
+}
+
+X509_CRL *OSSL_STORE_INFO_get1_CRL(const OSSL_STORE_INFO *info)
+{
+    if (info->type == OSSL_STORE_INFO_CRL) {
+        X509_CRL_up_ref(info->_.crl);
+        return info->_.crl;
+    }
+    OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_INFO_GET1_CRL,
+                  OSSL_STORE_R_NOT_A_CRL);
+    return NULL;
+}
+
+/*
+ * Free the OSSL_STORE_INFO
+ */
+void OSSL_STORE_INFO_free(OSSL_STORE_INFO *info)
+{
+    if (info != NULL) {
+        switch (info->type) {
+        case OSSL_STORE_INFO_NAME:
+            OPENSSL_free(info->_.name.name);
+            OPENSSL_free(info->_.name.desc);
+            break;
+        case OSSL_STORE_INFO_PARAMS:
+            EVP_PKEY_free(info->_.params);
+            break;
+        case OSSL_STORE_INFO_PKEY:
+            EVP_PKEY_free(info->_.pkey);
+            break;
+        case OSSL_STORE_INFO_CERT:
+            X509_free(info->_.x509);
+            break;
+        case OSSL_STORE_INFO_CRL:
+            X509_CRL_free(info->_.crl);
+            break;
+        }
+        OPENSSL_free(info);
+    }
+}
+
diff --git a/crypto/store/store_locl.h b/crypto/store/store_locl.h
new file mode 100644
index 0000000000..c8c409d767
--- /dev/null
+++ b/crypto/store/store_locl.h
@@ -0,0 +1,69 @@
+/*
+ * Copyright 2016-2017 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the OpenSSL license (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+#include "internal/thread_once.h"
+#include <openssl/dsa.h>
+#include <openssl/engine.h>
+#include <openssl/evp.h>
+#include <openssl/lhash.h>
+#include <openssl/x509.h>
+#include <openssl/store.h>
+
+/*-
+ *  OSSL_STORE_INFO stuff
+ *  ---------------------
+ */
+
+struct ossl_store_info_st {
+    int type;
+    union {
+        struct {
+            char *name;
+            char *desc;
+        } name;                  /* when type == OSSL_STORE_INFO_NAME */
+
+        EVP_PKEY *params;        /* when type == OSSL_STORE_INFO_PARAMS */
+        EVP_PKEY *pkey;          /* when type == OSSL_STORE_INFO_PKEY */
+        X509 *x509;              /* when type == OSSL_STORE_INFO_CERT */
+        X509_CRL *crl;           /* when type == OSSL_STORE_INFO_CRL */
+        void *data;              /* used internally */
+    } _;
+};
+
+DEFINE_STACK_OF(OSSL_STORE_INFO)
+
+/*-
+ *  OSSL_STORE_LOADER stuff
+ *  -----------------------
+ */
+
+int ossl_store_register_loader_int(OSSL_STORE_LOADER *loader);
+OSSL_STORE_LOADER *ossl_store_unregister_loader_int(const char *scheme);
+
+/* loader stuff */
+struct ossl_store_loader_st {
+    const char *scheme;
+    OSSL_STORE_open_fn open;
+    OSSL_STORE_ctrl_fn ctrl;
+    OSSL_STORE_load_fn load;
+    OSSL_STORE_eof_fn eof;
+    OSSL_STORE_error_fn error;
+    OSSL_STORE_close_fn close;
+};
+DEFINE_LHASH_OF(OSSL_STORE_LOADER);
+
+const OSSL_STORE_LOADER *ossl_store_get0_loader_int(const char *scheme);
+void ossl_store_destroy_loaders_int(void);
+
+/*-
+ *  OSSL_STORE init stuff
+ *  ---------------------
+ */
+
+int ossl_store_init_once(void);
diff --git a/crypto/store/store_register.c b/crypto/store/store_register.c
new file mode 100644
index 0000000000..a138edc636
--- /dev/null
+++ b/crypto/store/store_register.c
@@ -0,0 +1,259 @@
+/*
+ * Copyright 2016-2017 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the OpenSSL license (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+#include <string.h>
+#include <ctype.h>
+#include <assert.h>
+
+#include <openssl/err.h>
+#include <openssl/lhash.h>
+#include "store_locl.h"
+
+static CRYPTO_RWLOCK *registry_lock;
+static CRYPTO_ONCE registry_init = CRYPTO_ONCE_STATIC_INIT;
+
+DEFINE_RUN_ONCE_STATIC(do_registry_init)
+{
+    registry_lock = CRYPTO_THREAD_lock_new();
+    return registry_lock != NULL;
+}
+
+/*
+ *  Functions for manipulating OSSL_STORE_LOADERs
+ */
+
+OSSL_STORE_LOADER *OSSL_STORE_LOADER_new(const char *scheme)
+{
+    OSSL_STORE_LOADER *res = OPENSSL_zalloc(sizeof(*res));
+
+    if (res == NULL) {
+        OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_LOADER_NEW, ERR_R_MALLOC_FAILURE);
+        return NULL;
+    }
+
+    /*
+     * We usually don't check NULL arguments.  For loaders, though, the
+     * scheme is crucial and must never be NULL, or the user will get
+     * mysterious errors when trying to register the created loader
+     * later on.
+     */
+    if (scheme == NULL) {
+        OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_LOADER_NEW,
+                      OSSL_STORE_R_INVALID_SCHEME);
+        return NULL;
+    }
+
+    res->scheme = scheme;
+    return res;
+}
+
+const char *OSSL_STORE_LOADER_get0_scheme(const OSSL_STORE_LOADER *loader)
+{
+    return loader->scheme;
+}
+
+int OSSL_STORE_LOADER_set_open(OSSL_STORE_LOADER *loader,
+                               OSSL_STORE_open_fn open_function)
+{
+    loader->open = open_function;
+    return 1;
+}
+
+int OSSL_STORE_LOADER_set_ctrl(OSSL_STORE_LOADER *loader,
+                               OSSL_STORE_ctrl_fn ctrl_function)
+{
+    loader->ctrl = ctrl_function;
+    return 1;
+}
+
+int OSSL_STORE_LOADER_set_load(OSSL_STORE_LOADER *loader,
+                               OSSL_STORE_load_fn load_function)
+{
+    loader->load = load_function;
+    return 1;
+}
+
+int OSSL_STORE_LOADER_set_eof(OSSL_STORE_LOADER *loader,
+                              OSSL_STORE_eof_fn eof_function)
+{
+    loader->eof = eof_function;
+    return 1;
+}
+
+int OSSL_STORE_LOADER_set_error(OSSL_STORE_LOADER *loader,
+                                OSSL_STORE_error_fn error_function)
+{
+    loader->error = error_function;
+    return 1;
+}
+
+int OSSL_STORE_LOADER_set_close(OSSL_STORE_LOADER *loader,
+                                OSSL_STORE_close_fn close_function)
+{
+    loader->close = close_function;
+    return 1;
+}
+
+void OSSL_STORE_LOADER_free(OSSL_STORE_LOADER *loader)
+{
+    OPENSSL_free(loader);
+}
+
+/*
+ *  Functions for registering OSSL_STORE_LOADERs
+ */
+
+static unsigned long store_loader_hash(const OSSL_STORE_LOADER *v)
+{
+    return OPENSSL_LH_strhash(v->scheme);
+}
+
+static int store_loader_cmp(const OSSL_STORE_LOADER *a,
+                            const OSSL_STORE_LOADER *b)
+{
+    if (a->scheme != NULL && b->scheme != NULL)
+        return strcmp(a->scheme, b->scheme);
+    else if (a->scheme == b->scheme)
+        return 0;
+    return a->scheme == NULL ? -1 : 1;
+}
+
+static LHASH_OF(OSSL_STORE_LOADER) *loader_register = NULL;
+
+int ossl_store_register_loader_int(OSSL_STORE_LOADER *loader)
+{
+    const char *scheme = loader->scheme;
+    int ok = 0;
+
+    /*
+     * Check that the given scheme conforms to correct scheme syntax as per
+     * RFC 3986:
+     *
+     * scheme        = ALPHA *( ALPHA / DIGIT / "+" / "-" / "." )
+     */
+    if (isalpha(*scheme))
+        while (*scheme != '\0'
+               && (isalpha(*scheme)
+                   || isdigit(*scheme)
+                   || strchr("+-.", *scheme) != NULL))
+            scheme++;
+    if (*scheme != '\0') {
+        OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_REGISTER_LOADER_INT,
+                      OSSL_STORE_R_INVALID_SCHEME);
+        ERR_add_error_data(4, "scheme=", loader->scheme);
+        return 0;
+    }
+
+    if (!RUN_ONCE(&registry_init, do_registry_init)) {
+        OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_REGISTER_LOADER_INT,
+                      ERR_R_MALLOC_FAILURE);
+        return 0;
+    }
+    CRYPTO_THREAD_write_lock(registry_lock);
+
+    if (loader_register == NULL) {
+        loader_register = lh_OSSL_STORE_LOADER_new(store_loader_hash,
+                                                   store_loader_cmp);
+    }
+
+    if (loader_register != NULL
+        && (lh_OSSL_STORE_LOADER_insert(loader_register, loader) != NULL
+            || lh_OSSL_STORE_LOADER_error(loader_register) == 0))
+        ok = 1;
+
+    CRYPTO_THREAD_unlock(registry_lock);
+
+    return ok;
+}
+int OSSL_STORE_register_loader(OSSL_STORE_LOADER *loader)
+{
+    if (!ossl_store_init_once())
+        return 0;
+    return ossl_store_register_loader_int(loader);
+}
+
+const OSSL_STORE_LOADER *ossl_store_get0_loader_int(const char *scheme)
+{
+    OSSL_STORE_LOADER template;
+    OSSL_STORE_LOADER *loader = NULL;
+
+    template.scheme = scheme;
+    template.open = NULL;
+    template.load = NULL;
+    template.eof = NULL;
+    template.close = NULL;
+
+    if (!ossl_store_init_once())
+        return NULL;
+
+    if (!RUN_ONCE(&registry_init, do_registry_init)) {
+        OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_GET0_LOADER_INT,
+                      ERR_R_MALLOC_FAILURE);
+        return NULL;
+    }
+    CRYPTO_THREAD_write_lock(registry_lock);
+
+    loader = lh_OSSL_STORE_LOADER_retrieve(loader_register, &template);
+
+    if (loader == NULL) {
+        OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_GET0_LOADER_INT,
+                      OSSL_STORE_R_UNREGISTERED_SCHEME);
+        ERR_add_error_data(2, "scheme=", scheme);
+    }
+
+    CRYPTO_THREAD_unlock(registry_lock);
+
+    return loader;
+}
+
+OSSL_STORE_LOADER *ossl_store_unregister_loader_int(const char *scheme)
+{
+    OSSL_STORE_LOADER template;
+    OSSL_STORE_LOADER *loader = NULL;
+
+    template.scheme = scheme;
+    template.open = NULL;
+    template.load = NULL;
+    template.eof = NULL;
+    template.close = NULL;
+
+    if (!RUN_ONCE(&registry_init, do_registry_init)) {
+        OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_UNREGISTER_LOADER_INT,
+                      ERR_R_MALLOC_FAILURE);
+        return NULL;
+    }
+    CRYPTO_THREAD_write_lock(registry_lock);
+
+    loader = lh_OSSL_STORE_LOADER_delete(loader_register, &template);
+
+    if (loader == NULL) {
+        OSSL_STOREerr(OSSL_STORE_F_OSSL_STORE_UNREGISTER_LOADER_INT,
+                      OSSL_STORE_R_UNREGISTERED_SCHEME);
+        ERR_add_error_data(2, "scheme=", scheme);
+    }
+
+    CRYPTO_THREAD_unlock(registry_lock);
+
+    return loader;
+}
+OSSL_STORE_LOADER *OSSL_STORE_unregister_loader(const char *scheme)
+{
+    if (!ossl_store_init_once())
+        return 0;
+    return ossl_store_unregister_loader_int(scheme);
+}
+
+void ossl_store_destroy_loaders_int(void)
+{
+    assert(lh_OSSL_STORE_LOADER_num_items(loader_register) == 0);
+    lh_OSSL_STORE_LOADER_free(loader_register);
+    loader_register = NULL;
+    CRYPTO_THREAD_lock_free(registry_lock);
+    registry_lock = NULL;
+}
diff --git a/crypto/store/store_strings.c b/crypto/store/store_strings.c
new file mode 100644
index 0000000000..76cf316483
--- /dev/null
+++ b/crypto/store/store_strings.c
@@ -0,0 +1,28 @@
+/*
+ * Copyright 2016-2017 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the OpenSSL license (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+#include <openssl/store.h>
+
+static char *type_strings[] = {
+    "Name",                      /* OSSL_STORE_INFO_NAME */
+    "Parameters",                /* OSSL_STORE_INFO_PARAMS */
+    "Pkey",                      /* OSSL_STORE_INFO_PKEY */
+    "Certificate",               /* OSSL_STORE_INFO_CERT */
+    "CRL"                        /* OSSL_STORE_INFO_CRL */
+};
+
+const char *OSSL_STORE_INFO_type_string(int type)
+{
+    int types = sizeof(type_strings) / sizeof(type_strings[0]);
+
+    if (type < 1 || type > types)
+        return NULL;
+
+    return type_strings[type - 1];
+}