cmp_protect.c 11 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334
  1. /*
  2. * Copyright 2007-2021 The OpenSSL Project Authors. All Rights Reserved.
  3. * Copyright Nokia 2007-2019
  4. * Copyright Siemens AG 2015-2019
  5. *
  6. * Licensed under the Apache License 2.0 (the "License"). You may not use
  7. * this file except in compliance with the License. You can obtain a copy
  8. * in the file LICENSE in the source distribution or at
  9. * https://www.openssl.org/source/license.html
  10. */
  11. #include "cmp_local.h"
  12. /* explicit #includes not strictly needed since implied by the above: */
  13. #include <openssl/asn1t.h>
  14. #include <openssl/cmp.h>
  15. #include <openssl/crmf.h>
  16. #include <openssl/err.h>
  17. #include <openssl/x509.h>
  18. /*
  19. * This function is also used by the internal verify_PBMAC() in cmp_vfy.c.
  20. *
  21. * Calculate protection for given PKImessage according to
  22. * the algorithm and parameters in the message header's protectionAlg
  23. * using the credentials, library context, and property criteria in the ctx.
  24. *
  25. * returns ASN1_BIT_STRING representing the protection on success, else NULL
  26. */
  27. ASN1_BIT_STRING *ossl_cmp_calc_protection(const OSSL_CMP_CTX *ctx,
  28. const OSSL_CMP_MSG *msg)
  29. {
  30. ASN1_BIT_STRING *prot = NULL;
  31. OSSL_CMP_PROTECTEDPART prot_part;
  32. const ASN1_OBJECT *algorOID = NULL;
  33. const void *ppval = NULL;
  34. int pptype = 0;
  35. if (!ossl_assert(ctx != NULL && msg != NULL))
  36. return NULL;
  37. /* construct data to be signed */
  38. prot_part.header = msg->header;
  39. prot_part.body = msg->body;
  40. if (msg->header->protectionAlg == NULL) {
  41. ERR_raise(ERR_LIB_CMP, CMP_R_UNKNOWN_ALGORITHM_ID);
  42. return NULL;
  43. }
  44. X509_ALGOR_get0(&algorOID, &pptype, &ppval, msg->header->protectionAlg);
  45. if (OBJ_obj2nid(algorOID) == NID_id_PasswordBasedMAC) {
  46. int len;
  47. size_t prot_part_der_len;
  48. unsigned char *prot_part_der = NULL;
  49. size_t sig_len;
  50. unsigned char *protection = NULL;
  51. OSSL_CRMF_PBMPARAMETER *pbm = NULL;
  52. ASN1_STRING *pbm_str = NULL;
  53. const unsigned char *pbm_str_uc = NULL;
  54. if (ctx->secretValue == NULL) {
  55. ERR_raise(ERR_LIB_CMP, CMP_R_MISSING_PBM_SECRET);
  56. return NULL;
  57. }
  58. if (ppval == NULL) {
  59. ERR_raise(ERR_LIB_CMP, CMP_R_ERROR_CALCULATING_PROTECTION);
  60. return NULL;
  61. }
  62. len = i2d_OSSL_CMP_PROTECTEDPART(&prot_part, &prot_part_der);
  63. if (len < 0 || prot_part_der == NULL) {
  64. ERR_raise(ERR_LIB_CMP, CMP_R_ERROR_CALCULATING_PROTECTION);
  65. goto end;
  66. }
  67. prot_part_der_len = (size_t)len;
  68. pbm_str = (ASN1_STRING *)ppval;
  69. pbm_str_uc = pbm_str->data;
  70. pbm = d2i_OSSL_CRMF_PBMPARAMETER(NULL, &pbm_str_uc, pbm_str->length);
  71. if (pbm == NULL) {
  72. ERR_raise(ERR_LIB_CMP, CMP_R_WRONG_ALGORITHM_OID);
  73. goto end;
  74. }
  75. if (!OSSL_CRMF_pbm_new(ctx->libctx, ctx->propq,
  76. pbm, prot_part_der, prot_part_der_len,
  77. ctx->secretValue->data, ctx->secretValue->length,
  78. &protection, &sig_len))
  79. goto end;
  80. if ((prot = ASN1_BIT_STRING_new()) == NULL)
  81. return NULL;
  82. /* OpenSSL defaults all bit strings to be encoded as ASN.1 NamedBitList */
  83. prot->flags &= ~(ASN1_STRING_FLAG_BITS_LEFT | 0x07);
  84. prot->flags |= ASN1_STRING_FLAG_BITS_LEFT;
  85. if (!ASN1_BIT_STRING_set(prot, protection, sig_len)) {
  86. ASN1_BIT_STRING_free(prot);
  87. prot = NULL;
  88. }
  89. end:
  90. OSSL_CRMF_PBMPARAMETER_free(pbm);
  91. OPENSSL_free(protection);
  92. OPENSSL_free(prot_part_der);
  93. return prot;
  94. } else {
  95. int md_nid;
  96. const EVP_MD *md = NULL;
  97. if (ctx->pkey == NULL) {
  98. ERR_raise(ERR_LIB_CMP,
  99. CMP_R_MISSING_KEY_INPUT_FOR_CREATING_PROTECTION);
  100. return NULL;
  101. }
  102. if (!OBJ_find_sigid_algs(OBJ_obj2nid(algorOID), &md_nid, NULL)
  103. || (md = EVP_get_digestbynid(md_nid)) == NULL) {
  104. ERR_raise(ERR_LIB_CMP, CMP_R_UNKNOWN_ALGORITHM_ID);
  105. return NULL;
  106. }
  107. if ((prot = ASN1_BIT_STRING_new()) == NULL)
  108. return NULL;
  109. if (ASN1_item_sign_ex(ASN1_ITEM_rptr(OSSL_CMP_PROTECTEDPART), NULL,
  110. NULL, prot, &prot_part, NULL, ctx->pkey, md,
  111. ctx->libctx, ctx->propq))
  112. return prot;
  113. ASN1_BIT_STRING_free(prot);
  114. return NULL;
  115. }
  116. }
  117. int ossl_cmp_msg_add_extraCerts(OSSL_CMP_CTX *ctx, OSSL_CMP_MSG *msg)
  118. {
  119. if (!ossl_assert(ctx != NULL && msg != NULL))
  120. return 0;
  121. /* Add first ctx->cert and its chain if using signature-based protection */
  122. if (!ctx->unprotectedSend && ctx->secretValue == NULL
  123. && ctx->cert != NULL && ctx->pkey != NULL) {
  124. int prepend = X509_ADD_FLAG_UP_REF | X509_ADD_FLAG_NO_DUP
  125. | X509_ADD_FLAG_PREPEND | X509_ADD_FLAG_NO_SS;
  126. /* if not yet done try to build chain using available untrusted certs */
  127. if (ctx->chain == NULL) {
  128. ossl_cmp_debug(ctx,
  129. "trying to build chain for own CMP signer cert");
  130. ctx->chain =
  131. ossl_cmp_build_cert_chain(ctx->libctx, ctx->propq, NULL,
  132. ctx->untrusted, ctx->cert);
  133. if (ctx->chain != NULL) {
  134. ossl_cmp_debug(ctx,
  135. "success building chain for own CMP signer cert");
  136. } else {
  137. /* dump errors to avoid confusion when printing further ones */
  138. OSSL_CMP_CTX_print_errors(ctx);
  139. ossl_cmp_warn(ctx,
  140. "could not build chain for own CMP signer cert");
  141. }
  142. }
  143. if (ctx->chain != NULL) {
  144. if (!ossl_x509_add_certs_new(&msg->extraCerts, ctx->chain, prepend))
  145. return 0;
  146. } else {
  147. /* make sure that at least our own signer cert is included first */
  148. if (!ossl_x509_add_cert_new(&msg->extraCerts, ctx->cert, prepend))
  149. return 0;
  150. ossl_cmp_debug(ctx, "fallback: adding just own CMP signer cert");
  151. }
  152. }
  153. /* add any additional certificates from ctx->extraCertsOut */
  154. if (!ossl_x509_add_certs_new(&msg->extraCerts, ctx->extraCertsOut,
  155. X509_ADD_FLAG_UP_REF | X509_ADD_FLAG_NO_DUP))
  156. return 0;
  157. /* in case extraCerts are empty list avoid empty ASN.1 sequence */
  158. if (sk_X509_num(msg->extraCerts) == 0) {
  159. sk_X509_free(msg->extraCerts);
  160. msg->extraCerts = NULL;
  161. }
  162. return 1;
  163. }
  164. /*
  165. * Create an X509_ALGOR structure for PasswordBasedMAC protection based on
  166. * the pbm settings in the context
  167. */
  168. static int set_pbmac_algor(const OSSL_CMP_CTX *ctx, X509_ALGOR **alg)
  169. {
  170. OSSL_CRMF_PBMPARAMETER *pbm = NULL;
  171. unsigned char *pbm_der = NULL;
  172. int pbm_der_len;
  173. ASN1_STRING *pbm_str = NULL;
  174. if (!ossl_assert(ctx != NULL))
  175. return 0;
  176. pbm = OSSL_CRMF_pbmp_new(ctx->libctx, ctx->pbm_slen,
  177. EVP_MD_type(ctx->pbm_owf), ctx->pbm_itercnt,
  178. ctx->pbm_mac);
  179. pbm_str = ASN1_STRING_new();
  180. if (pbm == NULL || pbm_str == NULL)
  181. goto err;
  182. if ((pbm_der_len = i2d_OSSL_CRMF_PBMPARAMETER(pbm, &pbm_der)) < 0)
  183. goto err;
  184. if (!ASN1_STRING_set(pbm_str, pbm_der, pbm_der_len))
  185. goto err;
  186. if (*alg == NULL && (*alg = X509_ALGOR_new()) == NULL)
  187. goto err;
  188. OPENSSL_free(pbm_der);
  189. X509_ALGOR_set0(*alg, OBJ_nid2obj(NID_id_PasswordBasedMAC),
  190. V_ASN1_SEQUENCE, pbm_str);
  191. OSSL_CRMF_PBMPARAMETER_free(pbm);
  192. return 1;
  193. err:
  194. ASN1_STRING_free(pbm_str);
  195. OPENSSL_free(pbm_der);
  196. OSSL_CRMF_PBMPARAMETER_free(pbm);
  197. return 0;
  198. }
  199. static int set_sig_algor(const OSSL_CMP_CTX *ctx, X509_ALGOR **alg)
  200. {
  201. int nid = 0;
  202. ASN1_OBJECT *algo = NULL;
  203. if (!OBJ_find_sigid_by_algs(&nid, EVP_MD_type(ctx->digest),
  204. EVP_PKEY_id(ctx->pkey))) {
  205. ERR_raise(ERR_LIB_CMP, CMP_R_UNSUPPORTED_KEY_TYPE);
  206. return 0;
  207. }
  208. if ((algo = OBJ_nid2obj(nid)) == NULL)
  209. return 0;
  210. if (*alg == NULL && (*alg = X509_ALGOR_new()) == NULL)
  211. return 0;
  212. if (X509_ALGOR_set0(*alg, algo, V_ASN1_UNDEF, NULL))
  213. return 1;
  214. ASN1_OBJECT_free(algo);
  215. return 0;
  216. }
  217. static int set_senderKID(const OSSL_CMP_CTX *ctx, OSSL_CMP_MSG *msg,
  218. const ASN1_OCTET_STRING *id)
  219. {
  220. if (id == NULL)
  221. id = ctx->referenceValue; /* standard for PBM, fallback for sig-based */
  222. return id == NULL || ossl_cmp_hdr_set1_senderKID(msg->header, id);
  223. }
  224. int ossl_cmp_msg_protect(OSSL_CMP_CTX *ctx, OSSL_CMP_MSG *msg)
  225. {
  226. if (!ossl_assert(ctx != NULL && msg != NULL))
  227. return 0;
  228. /*
  229. * For the case of re-protection remove pre-existing protection.
  230. * TODO: Consider also removing any pre-existing extraCerts.
  231. */
  232. X509_ALGOR_free(msg->header->protectionAlg);
  233. msg->header->protectionAlg = NULL;
  234. ASN1_BIT_STRING_free(msg->protection);
  235. msg->protection = NULL;
  236. if (ctx->unprotectedSend) {
  237. if (!set_senderKID(ctx, msg, NULL))
  238. goto err;
  239. } else if (ctx->secretValue != NULL) {
  240. /* use PasswordBasedMac according to 5.1.3.1 if secretValue is given */
  241. if (!set_pbmac_algor(ctx, &msg->header->protectionAlg))
  242. goto err;
  243. if (!set_senderKID(ctx, msg, NULL))
  244. goto err;
  245. /*
  246. * will add any additional certificates from ctx->extraCertsOut
  247. * while not needed to validate the protection certificate,
  248. * the option to do this might be handy for certain use cases
  249. */
  250. } else if (ctx->cert != NULL && ctx->pkey != NULL) {
  251. /* use MSG_SIG_ALG according to 5.1.3.3 if client cert and key given */
  252. /* make sure that key and certificate match */
  253. if (!X509_check_private_key(ctx->cert, ctx->pkey)) {
  254. ERR_raise(ERR_LIB_CMP, CMP_R_CERT_AND_KEY_DO_NOT_MATCH);
  255. goto err;
  256. }
  257. if (!set_sig_algor(ctx, &msg->header->protectionAlg))
  258. goto err;
  259. /* set senderKID to keyIdentifier of the cert according to 5.1.1 */
  260. if (!set_senderKID(ctx, msg, X509_get0_subject_key_id(ctx->cert)))
  261. goto err;
  262. /*
  263. * will add ctx->cert followed, if possible, by its chain built
  264. * from ctx->untrusted, and then ctx->extraCertsOut
  265. */
  266. } else {
  267. ERR_raise(ERR_LIB_CMP,
  268. CMP_R_MISSING_KEY_INPUT_FOR_CREATING_PROTECTION);
  269. goto err;
  270. }
  271. if (!ctx->unprotectedSend
  272. && ((msg->protection = ossl_cmp_calc_protection(ctx, msg)) == NULL))
  273. goto err;
  274. /*
  275. * For signature-based protection add ctx->cert followed by its chain.
  276. * Finally add any additional certificates from ctx->extraCertsOut;
  277. * even if not needed to validate the protection
  278. * the option to do this might be handy for certain use cases.
  279. */
  280. if (!ossl_cmp_msg_add_extraCerts(ctx, msg))
  281. goto err;
  282. /*
  283. * As required by RFC 4210 section 5.1.1., if the sender name is not known
  284. * to the client it set to NULL-DN. In this case for identification at least
  285. * the senderKID must be set, where we took the referenceValue as fallback.
  286. */
  287. if (!(ossl_cmp_general_name_is_NULL_DN(msg->header->sender)
  288. && msg->header->senderKID == NULL))
  289. return 1;
  290. ERR_raise(ERR_LIB_CMP, CMP_R_MISSING_SENDER_IDENTIFICATION);
  291. err:
  292. ERR_raise(ERR_LIB_CMP, CMP_R_ERROR_PROTECTING_MESSAGE);
  293. return 0;
  294. }