1 /* 2 * Copyright 2022-2024 The OpenSSL Project Authors. All Rights Reserved. 3 * 4 * Licensed under the Apache License 2.0 (the "License"). You may not use 5 * this file except in compliance with the License. You can obtain a copy 6 * in the file LICENSE in the source distribution or at 7 * https://www.openssl.org/source/license.html 8 */ 9 10 #include <stdlib.h> 11 #include <string.h> 12 #include <openssl/crypto.h> 13 #include <openssl/err.h> 14 #include <openssl/kdf.h> 15 #include <openssl/proverr.h> 16 #include <openssl/core_names.h> 17 #include "prov/providercommon.h" 18 #include "prov/implementations.h" 19 #include "prov/hmac_drbg.h" 20 #include "prov/provider_ctx.h" 21 22 static OSSL_FUNC_kdf_newctx_fn hmac_drbg_kdf_new; 23 static OSSL_FUNC_kdf_dupctx_fn hmac_drbg_kdf_dup; 24 static OSSL_FUNC_kdf_freectx_fn hmac_drbg_kdf_free; 25 static OSSL_FUNC_kdf_reset_fn hmac_drbg_kdf_reset; 26 static OSSL_FUNC_kdf_derive_fn hmac_drbg_kdf_derive; 27 static OSSL_FUNC_kdf_settable_ctx_params_fn hmac_drbg_kdf_settable_ctx_params; 28 static OSSL_FUNC_kdf_set_ctx_params_fn hmac_drbg_kdf_set_ctx_params; 29 static OSSL_FUNC_kdf_gettable_ctx_params_fn hmac_drbg_kdf_gettable_ctx_params; 30 static OSSL_FUNC_kdf_get_ctx_params_fn hmac_drbg_kdf_get_ctx_params; 31 32 typedef struct { 33 PROV_DRBG_HMAC base; 34 void *provctx; 35 unsigned char *entropy, *nonce; 36 size_t entropylen, noncelen; 37 int init; 38 } KDF_HMAC_DRBG; 39 40 static void *hmac_drbg_kdf_new(void *provctx) 41 { 42 KDF_HMAC_DRBG *ctx; 43 44 if (!ossl_prov_is_running()) 45 return NULL; 46 47 ctx = OPENSSL_zalloc(sizeof(*ctx)); 48 if (ctx == NULL) { 49 ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE); 50 return NULL; 51 } 52 ctx->provctx = provctx; 53 return ctx; 54 } 55 56 static void hmac_drbg_kdf_reset(void *vctx) 57 { 58 KDF_HMAC_DRBG *ctx = (KDF_HMAC_DRBG *)vctx; 59 PROV_DRBG_HMAC *drbg = &ctx->base; 60 void *provctx = ctx->provctx; 61 62 EVP_MAC_CTX_free(drbg->ctx); 63 ossl_prov_digest_reset(&drbg->digest); 64 OPENSSL_clear_free(ctx->entropy, ctx->entropylen); 65 OPENSSL_clear_free(ctx->nonce, ctx->noncelen); 66 OPENSSL_cleanse(ctx, sizeof(*ctx)); 67 ctx->provctx = provctx; 68 } 69 70 static void hmac_drbg_kdf_free(void *vctx) 71 { 72 KDF_HMAC_DRBG *ctx = (KDF_HMAC_DRBG *)vctx; 73 74 if (ctx != NULL) { 75 hmac_drbg_kdf_reset(ctx); 76 OPENSSL_free(ctx); 77 } 78 } 79 80 static int ossl_drbg_hmac_dup(PROV_DRBG_HMAC *dst, const PROV_DRBG_HMAC *src) { 81 if (src->ctx != NULL) { 82 dst->ctx = EVP_MAC_CTX_dup(src->ctx); 83 if (dst->ctx == NULL) 84 return 0; 85 } 86 if (!ossl_prov_digest_copy(&dst->digest, &src->digest)) 87 return 0; 88 memcpy(dst->K, src->K, sizeof(dst->K)); 89 memcpy(dst->V, src->V, sizeof(dst->V)); 90 dst->blocklen = src->blocklen; 91 return 1; 92 } 93 94 static void *hmac_drbg_kdf_dup(void *vctx) 95 { 96 const KDF_HMAC_DRBG *src = (const KDF_HMAC_DRBG *)vctx; 97 KDF_HMAC_DRBG *dst; 98 99 dst = hmac_drbg_kdf_new(src->provctx); 100 if (dst != NULL) { 101 if (!ossl_drbg_hmac_dup(&dst->base, &src->base) 102 || !ossl_prov_memdup(src->entropy, src->entropylen, 103 &dst->entropy , &dst->entropylen) 104 || !ossl_prov_memdup(src->nonce, src->noncelen, 105 &dst->nonce, &dst->noncelen)) 106 goto err; 107 dst->init = src->init; 108 } 109 return dst; 110 111 err: 112 hmac_drbg_kdf_free(dst); 113 return NULL; 114 } 115 116 static int hmac_drbg_kdf_derive(void *vctx, unsigned char *out, size_t outlen, 117 const OSSL_PARAM params[]) 118 { 119 KDF_HMAC_DRBG *ctx = (KDF_HMAC_DRBG *)vctx; 120 PROV_DRBG_HMAC *drbg = &ctx->base; 121 122 if (!ossl_prov_is_running() 123 || !hmac_drbg_kdf_set_ctx_params(vctx, params)) 124 return 0; 125 if (!ctx->init) { 126 if (ctx->entropy == NULL 127 || ctx->entropylen == 0 128 || ctx->nonce == NULL 129 || ctx->noncelen == 0 130 || !ossl_drbg_hmac_init(drbg, ctx->entropy, ctx->entropylen, 131 ctx->nonce, ctx->noncelen, NULL, 0)) 132 return 0; 133 ctx->init = 1; 134 } 135 136 return ossl_drbg_hmac_generate(drbg, out, outlen, NULL, 0); 137 } 138 139 static int hmac_drbg_kdf_get_ctx_params(void *vctx, OSSL_PARAM params[]) 140 { 141 KDF_HMAC_DRBG *hmac = (KDF_HMAC_DRBG *)vctx; 142 PROV_DRBG_HMAC *drbg = &hmac->base; 143 const char *name; 144 const EVP_MD *md; 145 OSSL_PARAM *p; 146 147 p = OSSL_PARAM_locate(params, OSSL_KDF_PARAM_MAC); 148 if (p != NULL) { 149 if (drbg->ctx == NULL) 150 return 0; 151 name = EVP_MAC_get0_name(EVP_MAC_CTX_get0_mac(drbg->ctx)); 152 if (!OSSL_PARAM_set_utf8_string(p, name)) 153 return 0; 154 } 155 156 p = OSSL_PARAM_locate(params, OSSL_KDF_PARAM_DIGEST); 157 if (p != NULL) { 158 md = ossl_prov_digest_md(&drbg->digest); 159 if (md == NULL || !OSSL_PARAM_set_utf8_string(p, EVP_MD_get0_name(md))) 160 return 0; 161 } 162 return 1; 163 } 164 165 static const OSSL_PARAM *hmac_drbg_kdf_gettable_ctx_params( 166 ossl_unused void *vctx, ossl_unused void *p_ctx) 167 { 168 static const OSSL_PARAM known_gettable_ctx_params[] = { 169 OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_MAC, NULL, 0), 170 OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_DIGEST, NULL, 0), 171 OSSL_PARAM_END 172 }; 173 return known_gettable_ctx_params; 174 } 175 176 static int hmac_drbg_kdf_set_ctx_params(void *vctx, 177 const OSSL_PARAM params[]) 178 { 179 KDF_HMAC_DRBG *hmac = (KDF_HMAC_DRBG *)vctx; 180 PROV_DRBG_HMAC *drbg = &hmac->base; 181 OSSL_LIB_CTX *libctx = PROV_LIBCTX_OF(hmac->provctx); 182 const EVP_MD *md; 183 const OSSL_PARAM *p; 184 void *ptr = NULL; 185 size_t size = 0; 186 int md_size; 187 188 if (ossl_param_is_empty(params)) 189 return 1; 190 191 p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_HMACDRBG_ENTROPY); 192 if (p != NULL) { 193 if (!OSSL_PARAM_get_octet_string(p, &ptr, 0, &size)) 194 return 0; 195 OPENSSL_free(hmac->entropy); 196 hmac->entropy = ptr; 197 hmac->entropylen = size; 198 hmac->init = 0; 199 ptr = NULL; 200 } 201 202 p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_HMACDRBG_NONCE); 203 if (p != NULL) { 204 if (!OSSL_PARAM_get_octet_string(p, &ptr, 0, &size)) 205 return 0; 206 OPENSSL_free(hmac->nonce); 207 hmac->nonce = ptr; 208 hmac->noncelen = size; 209 hmac->init = 0; 210 } 211 212 p = OSSL_PARAM_locate_const(params, OSSL_ALG_PARAM_DIGEST); 213 if (p != NULL) { 214 if (!ossl_prov_digest_load_from_params(&drbg->digest, params, libctx)) 215 return 0; 216 217 /* Confirm digest is allowed. Allow all digests that are not XOF */ 218 md = ossl_prov_digest_md(&drbg->digest); 219 if (md != NULL) { 220 if (EVP_MD_xof(md)) { 221 ERR_raise(ERR_LIB_PROV, PROV_R_XOF_DIGESTS_NOT_ALLOWED); 222 return 0; 223 } 224 md_size = EVP_MD_get_size(md); 225 if (md_size <= 0) 226 return 0; 227 drbg->blocklen = (size_t)md_size; 228 } 229 return ossl_prov_macctx_load_from_params(&drbg->ctx, params, 230 "HMAC", NULL, NULL, libctx); 231 } 232 return 1; 233 } 234 235 static const OSSL_PARAM *hmac_drbg_kdf_settable_ctx_params( 236 ossl_unused void *vctx, ossl_unused void *p_ctx) 237 { 238 static const OSSL_PARAM known_settable_ctx_params[] = { 239 OSSL_PARAM_octet_string(OSSL_KDF_PARAM_HMACDRBG_ENTROPY, NULL, 0), 240 OSSL_PARAM_octet_string(OSSL_KDF_PARAM_HMACDRBG_NONCE, NULL, 0), 241 OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_DIGEST, NULL, 0), 242 OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_PROPERTIES, NULL, 0), 243 OSSL_PARAM_END 244 }; 245 return known_settable_ctx_params; 246 } 247 248 const OSSL_DISPATCH ossl_kdf_hmac_drbg_functions[] = { 249 { OSSL_FUNC_KDF_NEWCTX, (void(*)(void))hmac_drbg_kdf_new }, 250 { OSSL_FUNC_KDF_FREECTX, (void(*)(void))hmac_drbg_kdf_free }, 251 { OSSL_FUNC_KDF_DUPCTX, (void(*)(void))hmac_drbg_kdf_dup }, 252 { OSSL_FUNC_KDF_RESET, (void(*)(void))hmac_drbg_kdf_reset }, 253 { OSSL_FUNC_KDF_DERIVE, (void(*)(void))hmac_drbg_kdf_derive }, 254 { OSSL_FUNC_KDF_SETTABLE_CTX_PARAMS, 255 (void(*)(void))hmac_drbg_kdf_settable_ctx_params }, 256 { OSSL_FUNC_KDF_SET_CTX_PARAMS, 257 (void(*)(void))hmac_drbg_kdf_set_ctx_params }, 258 { OSSL_FUNC_KDF_GETTABLE_CTX_PARAMS, 259 (void(*)(void))hmac_drbg_kdf_gettable_ctx_params }, 260 { OSSL_FUNC_KDF_GET_CTX_PARAMS, 261 (void(*)(void))hmac_drbg_kdf_get_ctx_params }, 262 OSSL_DISPATCH_END 263 }; 264