| /* |
| * Copyright 2001-2022 The OpenSSL Project Authors. All Rights Reserved. |
| * |
| * Licensed under the Apache License 2.0 (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 |
| */ |
| |
| /* We need to use some engine deprecated APIs */ |
| #define OPENSSL_SUPPRESS_DEPRECATED |
| |
| #include "eng_local.h" |
| #include "internal/dso.h" |
| #include <openssl/crypto.h> |
| |
| /* |
| * Shared libraries implementing ENGINEs for use by the "dynamic" ENGINE |
| * loader should implement the hook-up functions with the following |
| * prototypes. |
| */ |
| |
| /* Our ENGINE handlers */ |
| static int dynamic_init(ENGINE *e); |
| static int dynamic_finish(ENGINE *e); |
| static int dynamic_ctrl(ENGINE *e, int cmd, long i, void *p, |
| void (*f) (void)); |
| /* Predeclare our context type */ |
| typedef struct st_dynamic_data_ctx dynamic_data_ctx; |
| /* The implementation for the important control command */ |
| static int dynamic_load(ENGINE *e, dynamic_data_ctx *ctx); |
| |
| #define DYNAMIC_CMD_SO_PATH ENGINE_CMD_BASE |
| #define DYNAMIC_CMD_NO_VCHECK (ENGINE_CMD_BASE + 1) |
| #define DYNAMIC_CMD_ID (ENGINE_CMD_BASE + 2) |
| #define DYNAMIC_CMD_LIST_ADD (ENGINE_CMD_BASE + 3) |
| #define DYNAMIC_CMD_DIR_LOAD (ENGINE_CMD_BASE + 4) |
| #define DYNAMIC_CMD_DIR_ADD (ENGINE_CMD_BASE + 5) |
| #define DYNAMIC_CMD_LOAD (ENGINE_CMD_BASE + 6) |
| |
| /* The constants used when creating the ENGINE */ |
| static const char *engine_dynamic_id = "dynamic"; |
| static const char *engine_dynamic_name = "Dynamic engine loading support"; |
| static const ENGINE_CMD_DEFN dynamic_cmd_defns[] = { |
| {DYNAMIC_CMD_SO_PATH, |
| "SO_PATH", |
| "Specifies the path to the new ENGINE shared library", |
| ENGINE_CMD_FLAG_STRING}, |
| {DYNAMIC_CMD_NO_VCHECK, |
| "NO_VCHECK", |
| "Specifies to continue even if version checking fails (boolean)", |
| ENGINE_CMD_FLAG_NUMERIC}, |
| {DYNAMIC_CMD_ID, |
| "ID", |
| "Specifies an ENGINE id name for loading", |
| ENGINE_CMD_FLAG_STRING}, |
| {DYNAMIC_CMD_LIST_ADD, |
| "LIST_ADD", |
| "Whether to add a loaded ENGINE to the internal list (0=no,1=yes,2=mandatory)", |
| ENGINE_CMD_FLAG_NUMERIC}, |
| {DYNAMIC_CMD_DIR_LOAD, |
| "DIR_LOAD", |
| "Specifies whether to load from 'DIR_ADD' directories (0=no,1=yes,2=mandatory)", |
| ENGINE_CMD_FLAG_NUMERIC}, |
| {DYNAMIC_CMD_DIR_ADD, |
| "DIR_ADD", |
| "Adds a directory from which ENGINEs can be loaded", |
| ENGINE_CMD_FLAG_STRING}, |
| {DYNAMIC_CMD_LOAD, |
| "LOAD", |
| "Load up the ENGINE specified by other settings", |
| ENGINE_CMD_FLAG_NO_INPUT}, |
| {0, NULL, NULL, 0} |
| }; |
| |
| /* |
| * Loading code stores state inside the ENGINE structure via the "ex_data" |
| * element. We load all our state into a single structure and use that as a |
| * single context in the "ex_data" stack. |
| */ |
| struct st_dynamic_data_ctx { |
| /* The DSO object we load that supplies the ENGINE code */ |
| DSO *dynamic_dso; |
| /* |
| * The function pointer to the version checking shared library function |
| */ |
| dynamic_v_check_fn v_check; |
| /* |
| * The function pointer to the engine-binding shared library function |
| */ |
| dynamic_bind_engine bind_engine; |
| /* The default name/path for loading the shared library */ |
| char *DYNAMIC_LIBNAME; |
| /* Whether to continue loading on a version check failure */ |
| int no_vcheck; |
| /* If non-NULL, stipulates the 'id' of the ENGINE to be loaded */ |
| char *engine_id; |
| /* |
| * If non-zero, a successfully loaded ENGINE should be added to the |
| * internal ENGINE list. If 2, the add must succeed or the entire load |
| * should fail. |
| */ |
| int list_add_value; |
| /* The symbol name for the version checking function */ |
| const char *DYNAMIC_F1; |
| /* The symbol name for the "initialise ENGINE structure" function */ |
| const char *DYNAMIC_F2; |
| /* |
| * Whether to never use 'dirs', use 'dirs' as a fallback, or only use |
| * 'dirs' for loading. Default is to use 'dirs' as a fallback. |
| */ |
| int dir_load; |
| /* A stack of directories from which ENGINEs could be loaded */ |
| STACK_OF(OPENSSL_STRING) *dirs; |
| }; |
| |
| /* |
| * This is the "ex_data" index we obtain and reserve for use with our context |
| * structure. |
| */ |
| static int dynamic_ex_data_idx = -1; |
| |
| static void int_free_str(char *s) |
| { |
| OPENSSL_free(s); |
| } |
| |
| /* |
| * Because our ex_data element may or may not get allocated depending on |
| * whether a "first-use" occurs before the ENGINE is freed, we have a memory |
| * leak problem to solve. We can't declare a "new" handler for the ex_data as |
| * we don't want a dynamic_data_ctx in *all* ENGINE structures of all types |
| * (this is a bug in the design of CRYPTO_EX_DATA). As such, we just declare |
| * a "free" handler and that will get called if an ENGINE is being destroyed |
| * and there was an ex_data element corresponding to our context type. |
| */ |
| static void dynamic_data_ctx_free_func(void *parent, void *ptr, |
| CRYPTO_EX_DATA *ad, int idx, long argl, |
| void *argp) |
| { |
| if (ptr) { |
| dynamic_data_ctx *ctx = (dynamic_data_ctx *)ptr; |
| DSO_free(ctx->dynamic_dso); |
| OPENSSL_free(ctx->DYNAMIC_LIBNAME); |
| OPENSSL_free(ctx->engine_id); |
| sk_OPENSSL_STRING_pop_free(ctx->dirs, int_free_str); |
| OPENSSL_free(ctx); |
| } |
| } |
| |
| /* |
| * Construct the per-ENGINE context. We create it blindly and then use a lock |
| * to check for a race - if so, all but one of the threads "racing" will have |
| * wasted their time. The alternative involves creating everything inside the |
| * lock which is far worse. |
| */ |
| static int dynamic_set_data_ctx(ENGINE *e, dynamic_data_ctx **ctx) |
| { |
| dynamic_data_ctx *c = OPENSSL_zalloc(sizeof(*c)); |
| int ret = 0; |
| |
| if (c == NULL) { |
| ERR_raise(ERR_LIB_ENGINE, ERR_R_MALLOC_FAILURE); |
| return 0; |
| } |
| c->dirs = sk_OPENSSL_STRING_new_null(); |
| if (c->dirs == NULL) { |
| ERR_raise(ERR_LIB_ENGINE, ERR_R_MALLOC_FAILURE); |
| goto end; |
| } |
| c->DYNAMIC_F1 = "v_check"; |
| c->DYNAMIC_F2 = "bind_engine"; |
| c->dir_load = 1; |
| if (!CRYPTO_THREAD_write_lock(global_engine_lock)) |
| goto end; |
| if ((*ctx = (dynamic_data_ctx *)ENGINE_get_ex_data(e, |
| dynamic_ex_data_idx)) |
| == NULL) { |
| /* Good, we're the first */ |
| ret = ENGINE_set_ex_data(e, dynamic_ex_data_idx, c); |
| if (ret) { |
| *ctx = c; |
| c = NULL; |
| } |
| } |
| CRYPTO_THREAD_unlock(global_engine_lock); |
| ret = 1; |
| /* |
| * If we lost the race to set the context, c is non-NULL and *ctx is the |
| * context of the thread that won. |
| */ |
| end: |
| if (c != NULL) |
| sk_OPENSSL_STRING_free(c->dirs); |
| OPENSSL_free(c); |
| return ret; |
| } |
| |
| /* |
| * This function retrieves the context structure from an ENGINE's "ex_data", |
| * or if it doesn't exist yet, sets it up. |
| */ |
| static dynamic_data_ctx *dynamic_get_data_ctx(ENGINE *e) |
| { |
| dynamic_data_ctx *ctx; |
| if (dynamic_ex_data_idx < 0) { |
| /* |
| * Create and register the ENGINE ex_data, and associate our "free" |
| * function with it to ensure any allocated contexts get freed when |
| * an ENGINE goes underground. |
| */ |
| int new_idx = ENGINE_get_ex_new_index(0, NULL, NULL, NULL, |
| dynamic_data_ctx_free_func); |
| if (new_idx == -1) { |
| ERR_raise(ERR_LIB_ENGINE, ENGINE_R_NO_INDEX); |
| return NULL; |
| } |
| if (!CRYPTO_THREAD_write_lock(global_engine_lock)) |
| return NULL; |
| /* Avoid a race by checking again inside this lock */ |
| if (dynamic_ex_data_idx < 0) { |
| /* Good, someone didn't beat us to it */ |
| dynamic_ex_data_idx = new_idx; |
| new_idx = -1; |
| } |
| CRYPTO_THREAD_unlock(global_engine_lock); |
| /* |
| * In theory we could "give back" the index here if (new_idx>-1), but |
| * it's not possible and wouldn't gain us much if it were. |
| */ |
| } |
| ctx = (dynamic_data_ctx *)ENGINE_get_ex_data(e, dynamic_ex_data_idx); |
| /* Check if the context needs to be created */ |
| if ((ctx == NULL) && !dynamic_set_data_ctx(e, &ctx)) |
| /* "set_data" will set errors if necessary */ |
| return NULL; |
| return ctx; |
| } |
| |
| static ENGINE *engine_dynamic(void) |
| { |
| ENGINE *ret = ENGINE_new(); |
| if (ret == NULL) |
| return NULL; |
| if (!ENGINE_set_id(ret, engine_dynamic_id) || |
| !ENGINE_set_name(ret, engine_dynamic_name) || |
| !ENGINE_set_init_function(ret, dynamic_init) || |
| !ENGINE_set_finish_function(ret, dynamic_finish) || |
| !ENGINE_set_ctrl_function(ret, dynamic_ctrl) || |
| !ENGINE_set_flags(ret, ENGINE_FLAGS_BY_ID_COPY) || |
| !ENGINE_set_cmd_defns(ret, dynamic_cmd_defns)) { |
| ENGINE_free(ret); |
| return NULL; |
| } |
| return ret; |
| } |
| |
| void engine_load_dynamic_int(void) |
| { |
| ENGINE *toadd = engine_dynamic(); |
| if (!toadd) |
| return; |
| |
| ERR_set_mark(); |
| ENGINE_add(toadd); |
| /* |
| * If the "add" worked, it gets a structural reference. So either way, we |
| * release our just-created reference. |
| */ |
| ENGINE_free(toadd); |
| /* |
| * If the "add" didn't work, it was probably a conflict because it was |
| * already added (eg. someone calling ENGINE_load_blah then calling |
| * ENGINE_load_builtin_engines() perhaps). |
| */ |
| ERR_pop_to_mark(); |
| } |
| |
| static int dynamic_init(ENGINE *e) |
| { |
| /* |
| * We always return failure - the "dynamic" engine itself can't be used |
| * for anything. |
| */ |
| return 0; |
| } |
| |
| static int dynamic_finish(ENGINE *e) |
| { |
| /* |
| * This should never be called on account of "dynamic_init" always |
| * failing. |
| */ |
| return 0; |
| } |
| |
| static int dynamic_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f) (void)) |
| { |
| dynamic_data_ctx *ctx = dynamic_get_data_ctx(e); |
| int initialised; |
| |
| if (!ctx) { |
| ERR_raise(ERR_LIB_ENGINE, ENGINE_R_NOT_LOADED); |
| return 0; |
| } |
| initialised = ((ctx->dynamic_dso == NULL) ? 0 : 1); |
| /* All our control commands require the ENGINE to be uninitialised */ |
| if (initialised) { |
| ERR_raise(ERR_LIB_ENGINE, ENGINE_R_ALREADY_LOADED); |
| return 0; |
| } |
| switch (cmd) { |
| case DYNAMIC_CMD_SO_PATH: |
| /* a NULL 'p' or a string of zero-length is the same thing */ |
| if (p && (strlen((const char *)p) < 1)) |
| p = NULL; |
| OPENSSL_free(ctx->DYNAMIC_LIBNAME); |
| if (p) |
| ctx->DYNAMIC_LIBNAME = OPENSSL_strdup(p); |
| else |
| ctx->DYNAMIC_LIBNAME = NULL; |
| return (ctx->DYNAMIC_LIBNAME ? 1 : 0); |
| case DYNAMIC_CMD_NO_VCHECK: |
| ctx->no_vcheck = ((i == 0) ? 0 : 1); |
| return 1; |
| case DYNAMIC_CMD_ID: |
| /* a NULL 'p' or a string of zero-length is the same thing */ |
| if (p && (strlen((const char *)p) < 1)) |
| p = NULL; |
| OPENSSL_free(ctx->engine_id); |
| if (p) |
| ctx->engine_id = OPENSSL_strdup(p); |
| else |
| ctx->engine_id = NULL; |
| return (ctx->engine_id ? 1 : 0); |
| case DYNAMIC_CMD_LIST_ADD: |
| if ((i < 0) || (i > 2)) { |
| ERR_raise(ERR_LIB_ENGINE, ENGINE_R_INVALID_ARGUMENT); |
| return 0; |
| } |
| ctx->list_add_value = (int)i; |
| return 1; |
| case DYNAMIC_CMD_LOAD: |
| return dynamic_load(e, ctx); |
| case DYNAMIC_CMD_DIR_LOAD: |
| if ((i < 0) || (i > 2)) { |
| ERR_raise(ERR_LIB_ENGINE, ENGINE_R_INVALID_ARGUMENT); |
| return 0; |
| } |
| ctx->dir_load = (int)i; |
| return 1; |
| case DYNAMIC_CMD_DIR_ADD: |
| /* a NULL 'p' or a string of zero-length is the same thing */ |
| if (p == NULL || (strlen((const char *)p) < 1)) { |
| ERR_raise(ERR_LIB_ENGINE, ENGINE_R_INVALID_ARGUMENT); |
| return 0; |
| } |
| { |
| char *tmp_str = OPENSSL_strdup(p); |
| if (tmp_str == NULL) { |
| ERR_raise(ERR_LIB_ENGINE, ERR_R_MALLOC_FAILURE); |
| return 0; |
| } |
| if (!sk_OPENSSL_STRING_push(ctx->dirs, tmp_str)) { |
| OPENSSL_free(tmp_str); |
| ERR_raise(ERR_LIB_ENGINE, ERR_R_MALLOC_FAILURE); |
| return 0; |
| } |
| } |
| return 1; |
| default: |
| break; |
| } |
| ERR_raise(ERR_LIB_ENGINE, ENGINE_R_CTRL_COMMAND_NOT_IMPLEMENTED); |
| return 0; |
| } |
| |
| static int int_load(dynamic_data_ctx *ctx) |
| { |
| int num, loop; |
| /* Unless told not to, try a direct load */ |
| if ((ctx->dir_load != 2) && (DSO_load(ctx->dynamic_dso, |
| ctx->DYNAMIC_LIBNAME, NULL, |
| 0)) != NULL) |
| return 1; |
| /* If we're not allowed to use 'dirs' or we have none, fail */ |
| if (!ctx->dir_load || (num = sk_OPENSSL_STRING_num(ctx->dirs)) < 1) |
| return 0; |
| for (loop = 0; loop < num; loop++) { |
| const char *s = sk_OPENSSL_STRING_value(ctx->dirs, loop); |
| char *merge = DSO_merge(ctx->dynamic_dso, ctx->DYNAMIC_LIBNAME, s); |
| if (!merge) |
| return 0; |
| if (DSO_load(ctx->dynamic_dso, merge, NULL, 0)) { |
| /* Found what we're looking for */ |
| OPENSSL_free(merge); |
| return 1; |
| } |
| OPENSSL_free(merge); |
| } |
| return 0; |
| } |
| |
| /* |
| * Unfortunately the version checker does not distinguish between |
| * engines built for openssl 1.1.x and openssl 3.x, but loading |
| * an engine that is built for openssl 1.1.x will cause a fatal |
| * error. Detect such engines, since EVP_PKEY_base_id is exported |
| * as a function in openssl 1.1.x, while it is named EVP_PKEY_get_base_id |
| * in openssl 3.x. Therefore we take the presence of that symbol |
| * as an indication that the engine will be incompatible. |
| */ |
| static int using_libcrypto_11(dynamic_data_ctx *ctx) |
| { |
| int ret; |
| |
| ERR_set_mark(); |
| ret = DSO_bind_func(ctx->dynamic_dso, "EVP_PKEY_base_id") != NULL; |
| ERR_pop_to_mark(); |
| |
| return ret; |
| } |
| |
| static int dynamic_load(ENGINE *e, dynamic_data_ctx *ctx) |
| { |
| ENGINE cpy; |
| dynamic_fns fns; |
| |
| if (ctx->dynamic_dso == NULL) |
| ctx->dynamic_dso = DSO_new(); |
| if (ctx->dynamic_dso == NULL) |
| return 0; |
| if (!ctx->DYNAMIC_LIBNAME) { |
| if (!ctx->engine_id) |
| return 0; |
| DSO_ctrl(ctx->dynamic_dso, DSO_CTRL_SET_FLAGS, |
| DSO_FLAG_NAME_TRANSLATION_EXT_ONLY, NULL); |
| ctx->DYNAMIC_LIBNAME = |
| DSO_convert_filename(ctx->dynamic_dso, ctx->engine_id); |
| } |
| if (!int_load(ctx)) { |
| ERR_raise(ERR_LIB_ENGINE, ENGINE_R_DSO_NOT_FOUND); |
| DSO_free(ctx->dynamic_dso); |
| ctx->dynamic_dso = NULL; |
| return 0; |
| } |
| /* We have to find a bind function otherwise it'll always end badly */ |
| if (! |
| (ctx->bind_engine = |
| (dynamic_bind_engine) DSO_bind_func(ctx->dynamic_dso, |
| ctx->DYNAMIC_F2))) { |
| ctx->bind_engine = NULL; |
| DSO_free(ctx->dynamic_dso); |
| ctx->dynamic_dso = NULL; |
| ERR_raise(ERR_LIB_ENGINE, ENGINE_R_DSO_FAILURE); |
| return 0; |
| } |
| /* Do we perform version checking? */ |
| if (!ctx->no_vcheck) { |
| unsigned long vcheck_res = 0; |
| /* |
| * Now we try to find a version checking function and decide how to |
| * cope with failure if/when it fails. |
| */ |
| ctx->v_check = |
| (dynamic_v_check_fn) DSO_bind_func(ctx->dynamic_dso, |
| ctx->DYNAMIC_F1); |
| if (ctx->v_check) |
| vcheck_res = ctx->v_check(OSSL_DYNAMIC_VERSION); |
| /* |
| * We fail if the version checker veto'd the load *or* if it is |
| * deferring to us (by returning its version) and we think it is too |
| * old. Also fail if this is engine for openssl 1.1.x. |
| */ |
| if (vcheck_res < OSSL_DYNAMIC_OLDEST || using_libcrypto_11(ctx)) { |
| /* Fail */ |
| ctx->bind_engine = NULL; |
| ctx->v_check = NULL; |
| DSO_free(ctx->dynamic_dso); |
| ctx->dynamic_dso = NULL; |
| ERR_raise(ERR_LIB_ENGINE, ENGINE_R_VERSION_INCOMPATIBILITY); |
| return 0; |
| } |
| } |
| /* |
| * First binary copy the ENGINE structure so that we can roll back if the |
| * hand-over fails |
| */ |
| memcpy(&cpy, e, sizeof(ENGINE)); |
| /* |
| * Provide the ERR, "ex_data", memory, and locking callbacks so the |
| * loaded library uses our state rather than its own. FIXME: As noted in |
| * engine.h, much of this would be simplified if each area of code |
| * provided its own "summary" structure of all related callbacks. It |
| * would also increase opaqueness. |
| */ |
| fns.static_state = ENGINE_get_static_state(); |
| CRYPTO_get_mem_functions(&fns.mem_fns.malloc_fn, &fns.mem_fns.realloc_fn, |
| &fns.mem_fns.free_fn); |
| /* |
| * Now that we've loaded the dynamic engine, make sure no "dynamic" |
| * ENGINE elements will show through. |
| */ |
| engine_set_all_null(e); |
| |
| /* Try to bind the ENGINE onto our own ENGINE structure */ |
| if (!engine_add_dynamic_id(e, (ENGINE_DYNAMIC_ID)ctx->bind_engine, 1) |
| || !ctx->bind_engine(e, ctx->engine_id, &fns)) { |
| engine_remove_dynamic_id(e, 1); |
| ctx->bind_engine = NULL; |
| ctx->v_check = NULL; |
| DSO_free(ctx->dynamic_dso); |
| ctx->dynamic_dso = NULL; |
| ERR_raise(ERR_LIB_ENGINE, ENGINE_R_INIT_FAILED); |
| /* Copy the original ENGINE structure back */ |
| memcpy(e, &cpy, sizeof(ENGINE)); |
| return 0; |
| } |
| /* Do we try to add this ENGINE to the internal list too? */ |
| if (ctx->list_add_value > 0) { |
| if (!ENGINE_add(e)) { |
| /* Do we tolerate this or fail? */ |
| if (ctx->list_add_value > 1) { |
| /* |
| * Fail - NB: By this time, it's too late to rollback, and |
| * trying to do so allows the bind_engine() code to have |
| * created leaks. We just have to fail where we are, after |
| * the ENGINE has changed. |
| */ |
| ERR_raise(ERR_LIB_ENGINE, ENGINE_R_CONFLICTING_ENGINE_ID); |
| return 0; |
| } |
| /* Tolerate */ |
| ERR_clear_error(); |
| } |
| } |
| return 1; |
| } |
