/* * Copyright 2006-2018 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 */ #include "apps.h" #include "progs.h" #include #include #include #include #include #define KEY_NONE 0 #define KEY_PRIVKEY 1 #define KEY_PUBKEY 2 #define KEY_CERT 3 static EVP_PKEY_CTX *init_ctx(const char *kdfalg, int *pkeysize, const char *keyfile, int keyform, int key_type, char *passinarg, int pkey_op, ENGINE *e, const int impl, int rawin, EVP_PKEY **ppkey); static int setup_peer(EVP_PKEY_CTX *ctx, int peerform, const char *file, ENGINE *e); static int do_keyop(EVP_PKEY_CTX *ctx, int pkey_op, unsigned char *out, size_t *poutlen, const unsigned char *in, size_t inlen); static int do_raw_keyop(int pkey_op, EVP_PKEY_CTX *ctx, const EVP_MD *md, EVP_PKEY *pkey, BIO *in, int filesize, unsigned char *sig, int siglen, unsigned char **out, size_t *poutlen); typedef enum OPTION_choice { OPT_ERR = -1, OPT_EOF = 0, OPT_HELP, OPT_ENGINE, OPT_ENGINE_IMPL, OPT_IN, OPT_OUT, OPT_PUBIN, OPT_CERTIN, OPT_ASN1PARSE, OPT_HEXDUMP, OPT_SIGN, OPT_VERIFY, OPT_VERIFYRECOVER, OPT_REV, OPT_ENCRYPT, OPT_DECRYPT, OPT_DERIVE, OPT_SIGFILE, OPT_INKEY, OPT_PEERKEY, OPT_PASSIN, OPT_PEERFORM, OPT_KEYFORM, OPT_PKEYOPT, OPT_PKEYOPT_PASSIN, OPT_KDF, OPT_KDFLEN, OPT_R_ENUM, OPT_RAWIN, OPT_DIGEST } OPTION_CHOICE; const OPTIONS pkeyutl_options[] = { {"help", OPT_HELP, '-', "Display this summary"}, {"in", OPT_IN, '<', "Input file - default stdin"}, {"rawin", OPT_RAWIN, '-', "Indicate the input data is in raw form"}, {"digest", OPT_DIGEST, 's', "Specify the digest algorithm when signing the raw input data"}, {"out", OPT_OUT, '>', "Output file - default stdout"}, {"pubin", OPT_PUBIN, '-', "Input is a public key"}, {"certin", OPT_CERTIN, '-', "Input is a cert with a public key"}, {"asn1parse", OPT_ASN1PARSE, '-', "asn1parse the output data"}, {"hexdump", OPT_HEXDUMP, '-', "Hex dump output"}, {"sign", OPT_SIGN, '-', "Sign input data with private key"}, {"verify", OPT_VERIFY, '-', "Verify with public key"}, {"verifyrecover", OPT_VERIFYRECOVER, '-', "Verify with public key, recover original data"}, {"rev", OPT_REV, '-', "Reverse the order of the input buffer"}, {"encrypt", OPT_ENCRYPT, '-', "Encrypt input data with public key"}, {"decrypt", OPT_DECRYPT, '-', "Decrypt input data with private key"}, {"derive", OPT_DERIVE, '-', "Derive shared secret"}, {"kdf", OPT_KDF, 's', "Use KDF algorithm"}, {"kdflen", OPT_KDFLEN, 'p', "KDF algorithm output length"}, {"sigfile", OPT_SIGFILE, '<', "Signature file (verify operation only)"}, {"inkey", OPT_INKEY, 's', "Input private key file"}, {"peerkey", OPT_PEERKEY, 's', "Peer key file used in key derivation"}, {"passin", OPT_PASSIN, 's', "Input file pass phrase source"}, {"peerform", OPT_PEERFORM, 'E', "Peer key format - default PEM"}, {"keyform", OPT_KEYFORM, 'E', "Private key format - default PEM"}, {"pkeyopt", OPT_PKEYOPT, 's', "Public key options as opt:value"}, {"pkeyopt_passin", OPT_PKEYOPT_PASSIN, 's', "Public key option that is read as a passphrase argument opt:passphrase"}, OPT_R_OPTIONS, #ifndef OPENSSL_NO_ENGINE {"engine", OPT_ENGINE, 's', "Use engine, possibly a hardware device"}, {"engine_impl", OPT_ENGINE_IMPL, '-', "Also use engine given by -engine for crypto operations"}, #endif {NULL} }; int pkeyutl_main(int argc, char **argv) { BIO *in = NULL, *out = NULL; ENGINE *e = NULL; EVP_PKEY_CTX *ctx = NULL; EVP_PKEY *pkey = NULL; char *infile = NULL, *outfile = NULL, *sigfile = NULL, *passinarg = NULL; char hexdump = 0, asn1parse = 0, rev = 0, *prog; unsigned char *buf_in = NULL, *buf_out = NULL, *sig = NULL; OPTION_CHOICE o; int buf_inlen = 0, siglen = -1, keyform = FORMAT_PEM, peerform = FORMAT_PEM; int keysize = -1, pkey_op = EVP_PKEY_OP_SIGN, key_type = KEY_PRIVKEY; int engine_impl = 0; int ret = 1, rv = -1; size_t buf_outlen; const char *inkey = NULL; const char *peerkey = NULL; const char *kdfalg = NULL; int kdflen = 0; STACK_OF(OPENSSL_STRING) *pkeyopts = NULL; STACK_OF(OPENSSL_STRING) *pkeyopts_passin = NULL; int rawin = 0; const EVP_MD *md = NULL; int filesize = -1; prog = opt_init(argc, argv, pkeyutl_options); while ((o = opt_next()) != OPT_EOF) { switch (o) { case OPT_EOF: case OPT_ERR: opthelp: BIO_printf(bio_err, "%s: Use -help for summary.\n", prog); goto end; case OPT_HELP: opt_help(pkeyutl_options); ret = 0; goto end; case OPT_IN: infile = opt_arg(); break; case OPT_OUT: outfile = opt_arg(); break; case OPT_SIGFILE: sigfile = opt_arg(); break; case OPT_ENGINE_IMPL: engine_impl = 1; break; case OPT_INKEY: inkey = opt_arg(); break; case OPT_PEERKEY: peerkey = opt_arg(); break; case OPT_PASSIN: passinarg = opt_arg(); break; case OPT_PEERFORM: if (!opt_format(opt_arg(), OPT_FMT_PDE, &peerform)) goto opthelp; break; case OPT_KEYFORM: if (!opt_format(opt_arg(), OPT_FMT_PDE, &keyform)) goto opthelp; break; case OPT_R_CASES: if (!opt_rand(o)) goto end; break; case OPT_ENGINE: e = setup_engine(opt_arg(), 0); break; case OPT_PUBIN: key_type = KEY_PUBKEY; break; case OPT_CERTIN: key_type = KEY_CERT; break; case OPT_ASN1PARSE: asn1parse = 1; break; case OPT_HEXDUMP: hexdump = 1; break; case OPT_SIGN: pkey_op = EVP_PKEY_OP_SIGN; break; case OPT_VERIFY: pkey_op = EVP_PKEY_OP_VERIFY; break; case OPT_VERIFYRECOVER: pkey_op = EVP_PKEY_OP_VERIFYRECOVER; break; case OPT_ENCRYPT: pkey_op = EVP_PKEY_OP_ENCRYPT; break; case OPT_DECRYPT: pkey_op = EVP_PKEY_OP_DECRYPT; break; case OPT_DERIVE: pkey_op = EVP_PKEY_OP_DERIVE; break; case OPT_KDF: pkey_op = EVP_PKEY_OP_DERIVE; key_type = KEY_NONE; kdfalg = opt_arg(); break; case OPT_KDFLEN: kdflen = atoi(opt_arg()); break; case OPT_REV: rev = 1; break; case OPT_PKEYOPT: if ((pkeyopts == NULL && (pkeyopts = sk_OPENSSL_STRING_new_null()) == NULL) || sk_OPENSSL_STRING_push(pkeyopts, opt_arg()) == 0) { BIO_puts(bio_err, "out of memory\n"); goto end; } break; case OPT_PKEYOPT_PASSIN: if ((pkeyopts_passin == NULL && (pkeyopts_passin = sk_OPENSSL_STRING_new_null()) == NULL) || sk_OPENSSL_STRING_push(pkeyopts_passin, opt_arg()) == 0) { BIO_puts(bio_err, "out of memory\n"); goto end; } break; case OPT_RAWIN: rawin = 1; break; case OPT_DIGEST: if (!opt_md(opt_arg(), &md)) goto end; break; } } argc = opt_num_rest(); if (argc != 0) goto opthelp; if (rawin && pkey_op != EVP_PKEY_OP_SIGN && pkey_op != EVP_PKEY_OP_VERIFY) { BIO_printf(bio_err, "%s: -rawin can only be used with -sign or -verify\n", prog); goto opthelp; } if (md != NULL && !rawin) { BIO_printf(bio_err, "%s: -digest can only be used with -rawin\n", prog); goto opthelp; } if (rawin && rev) { BIO_printf(bio_err, "%s: -rev cannot be used with raw input\n", prog); goto opthelp; } if (kdfalg != NULL) { if (kdflen == 0) { BIO_printf(bio_err, "%s: no KDF length given (-kdflen parameter).\n", prog); goto opthelp; } } else if (inkey == NULL) { BIO_printf(bio_err, "%s: no private key given (-inkey parameter).\n", prog); goto opthelp; } else if (peerkey != NULL && pkey_op != EVP_PKEY_OP_DERIVE) { BIO_printf(bio_err, "%s: no peer key given (-peerkey parameter).\n", prog); goto opthelp; } ctx = init_ctx(kdfalg, &keysize, inkey, keyform, key_type, passinarg, pkey_op, e, engine_impl, rawin, &pkey); if (ctx == NULL) { BIO_printf(bio_err, "%s: Error initializing context\n", prog); ERR_print_errors(bio_err); goto end; } if (peerkey != NULL && !setup_peer(ctx, peerform, peerkey, e)) { BIO_printf(bio_err, "%s: Error setting up peer key\n", prog); ERR_print_errors(bio_err); goto end; } if (pkeyopts != NULL) { int num = sk_OPENSSL_STRING_num(pkeyopts); int i; for (i = 0; i < num; ++i) { const char *opt = sk_OPENSSL_STRING_value(pkeyopts, i); if (pkey_ctrl_string(ctx, opt) <= 0) { BIO_printf(bio_err, "%s: Can't set parameter \"%s\":\n", prog, opt); ERR_print_errors(bio_err); goto end; } } } if (pkeyopts_passin != NULL) { int num = sk_OPENSSL_STRING_num(pkeyopts_passin); int i; for (i = 0; i < num; i++) { char *opt = sk_OPENSSL_STRING_value(pkeyopts_passin, i); char *passin = strchr(opt, ':'); char *passwd; if (passin == NULL) { /* Get password interactively */ char passwd_buf[4096]; BIO_snprintf(passwd_buf, sizeof(passwd_buf), "Enter %s: ", opt); EVP_read_pw_string(passwd_buf, sizeof(passwd_buf) - 1, passwd_buf, 0); passwd = OPENSSL_strdup(passwd_buf); if (passwd == NULL) { BIO_puts(bio_err, "out of memory\n"); goto end; } } else { /* Get password as a passin argument: First split option name * and passphrase argument into two strings */ *passin = 0; passin++; if (app_passwd(passin, NULL, &passwd, NULL) == 0) { BIO_printf(bio_err, "failed to get '%s'\n", opt); goto end; } } if (EVP_PKEY_CTX_ctrl_str(ctx, opt, passwd) <= 0) { BIO_printf(bio_err, "%s: Can't set parameter \"%s\":\n", prog, opt); goto end; } OPENSSL_free(passwd); } } if (sigfile != NULL && (pkey_op != EVP_PKEY_OP_VERIFY)) { BIO_printf(bio_err, "%s: Signature file specified for non verify\n", prog); goto end; } if (sigfile == NULL && (pkey_op == EVP_PKEY_OP_VERIFY)) { BIO_printf(bio_err, "%s: No signature file specified for verify\n", prog); goto end; } if (pkey_op != EVP_PKEY_OP_DERIVE) { in = bio_open_default(infile, 'r', FORMAT_BINARY); if (infile != NULL) { struct stat st; if (stat(infile, &st) == 0 && st.st_size <= INT_MAX) filesize = (int)st.st_size; } if (in == NULL) goto end; } out = bio_open_default(outfile, 'w', FORMAT_BINARY); if (out == NULL) goto end; if (sigfile != NULL) { BIO *sigbio = BIO_new_file(sigfile, "rb"); if (sigbio == NULL) { BIO_printf(bio_err, "Can't open signature file %s\n", sigfile); goto end; } siglen = bio_to_mem(&sig, keysize * 10, sigbio); BIO_free(sigbio); if (siglen < 0) { BIO_printf(bio_err, "Error reading signature data\n"); goto end; } } /* Raw input data is handled elsewhere */ if (in != NULL && !rawin) { /* Read the input data */ buf_inlen = bio_to_mem(&buf_in, keysize * 10, in); if (buf_inlen < 0) { BIO_printf(bio_err, "Error reading input Data\n"); goto end; } if (rev) { size_t i; unsigned char ctmp; size_t l = (size_t)buf_inlen; for (i = 0; i < l / 2; i++) { ctmp = buf_in[i]; buf_in[i] = buf_in[l - 1 - i]; buf_in[l - 1 - i] = ctmp; } } } /* Sanity check the input if the input is not raw */ if (!rawin && buf_inlen > EVP_MAX_MD_SIZE && (pkey_op == EVP_PKEY_OP_SIGN || pkey_op == EVP_PKEY_OP_VERIFY || pkey_op == EVP_PKEY_OP_VERIFYRECOVER)) { BIO_printf(bio_err, "Error: The input data looks too long to be a hash\n"); goto end; } if (pkey_op == EVP_PKEY_OP_VERIFY) { if (rawin) { rv = do_raw_keyop(pkey_op, ctx, md, pkey, in, filesize, sig, siglen, NULL, 0); } else { rv = EVP_PKEY_verify(ctx, sig, (size_t)siglen, buf_in, (size_t)buf_inlen); } if (rv == 1) { BIO_puts(out, "Signature Verified Successfully\n"); ret = 0; } else { BIO_puts(out, "Signature Verification Failure\n"); } goto end; } if (kdflen != 0) { buf_outlen = kdflen; rv = 1; } else { if (rawin) { /* rawin allocates the buffer in do_raw_keyop() */ rv = do_raw_keyop(pkey_op, ctx, md, pkey, in, filesize, NULL, 0, &buf_out, (size_t *)&buf_outlen); } else { rv = do_keyop(ctx, pkey_op, NULL, (size_t *)&buf_outlen, buf_in, (size_t)buf_inlen); if (rv > 0 && buf_outlen != 0) { buf_out = app_malloc(buf_outlen, "buffer output"); rv = do_keyop(ctx, pkey_op, buf_out, (size_t *)&buf_outlen, buf_in, (size_t)buf_inlen); } } } if (rv <= 0) { if (pkey_op != EVP_PKEY_OP_DERIVE) { BIO_puts(bio_err, "Public Key operation error\n"); } else { BIO_puts(bio_err, "Key derivation failed\n"); } ERR_print_errors(bio_err); goto end; } ret = 0; if (asn1parse) { if (!ASN1_parse_dump(out, buf_out, buf_outlen, 1, -1)) ERR_print_errors(bio_err); } else if (hexdump) { BIO_dump(out, (char *)buf_out, buf_outlen); } else { BIO_write(out, buf_out, buf_outlen); } end: EVP_PKEY_CTX_free(ctx); release_engine(e); BIO_free(in); BIO_free_all(out); OPENSSL_free(buf_in); OPENSSL_free(buf_out); OPENSSL_free(sig); sk_OPENSSL_STRING_free(pkeyopts); sk_OPENSSL_STRING_free(pkeyopts_passin); return ret; } static EVP_PKEY_CTX *init_ctx(const char *kdfalg, int *pkeysize, const char *keyfile, int keyform, int key_type, char *passinarg, int pkey_op, ENGINE *e, const int engine_impl, int rawin, EVP_PKEY **ppkey) { EVP_PKEY *pkey = NULL; EVP_PKEY_CTX *ctx = NULL; ENGINE *impl = NULL; char *passin = NULL; int rv = -1; X509 *x; if (((pkey_op == EVP_PKEY_OP_SIGN) || (pkey_op == EVP_PKEY_OP_DECRYPT) || (pkey_op == EVP_PKEY_OP_DERIVE)) && (key_type != KEY_PRIVKEY && kdfalg == NULL)) { BIO_printf(bio_err, "A private key is needed for this operation\n"); goto end; } if (!app_passwd(passinarg, NULL, &passin, NULL)) { BIO_printf(bio_err, "Error getting password\n"); goto end; } switch (key_type) { case KEY_PRIVKEY: pkey = load_key(keyfile, keyform, 0, passin, e, "Private Key"); break; case KEY_PUBKEY: pkey = load_pubkey(keyfile, keyform, 0, NULL, e, "Public Key"); break; case KEY_CERT: x = load_cert(keyfile, keyform, "Certificate"); if (x) { pkey = X509_get_pubkey(x); X509_free(x); } break; case KEY_NONE: break; } #ifndef OPENSSL_NO_ENGINE if (engine_impl) impl = e; #endif if (kdfalg != NULL) { int kdfnid = OBJ_sn2nid(kdfalg); if (kdfnid == NID_undef) { kdfnid = OBJ_ln2nid(kdfalg); if (kdfnid == NID_undef) { BIO_printf(bio_err, "The given KDF \"%s\" is unknown.\n", kdfalg); goto end; } } ctx = EVP_PKEY_CTX_new_id(kdfnid, impl); } else { if (pkey == NULL) goto end; #ifndef OPENSSL_NO_EC /* SM2 needs a special treatment */ if (EVP_PKEY_id(pkey) == EVP_PKEY_EC) { EC_KEY *eckey = NULL; const EC_GROUP *group = NULL; int nid; if ((eckey = EVP_PKEY_get0_EC_KEY(pkey)) == NULL || (group = EC_KEY_get0_group(eckey)) == NULL || (nid = EC_GROUP_get_curve_name(group)) == 0) goto end; if (nid == NID_sm2) EVP_PKEY_set_alias_type(pkey, EVP_PKEY_SM2); } #endif *pkeysize = EVP_PKEY_size(pkey); ctx = EVP_PKEY_CTX_new(pkey, impl); if (ppkey != NULL) *ppkey = pkey; EVP_PKEY_free(pkey); } if (ctx == NULL) goto end; /* * If rawin then we don't need to actually initialise the EVP_PKEY_CTX * itself. That will get initialised during EVP_DigestSignInit or * EVP_DigestVerifyInit. */ if (rawin) { rv = 1; } else { switch (pkey_op) { case EVP_PKEY_OP_SIGN: rv = EVP_PKEY_sign_init(ctx); break; case EVP_PKEY_OP_VERIFY: rv = EVP_PKEY_verify_init(ctx); break; case EVP_PKEY_OP_VERIFYRECOVER: rv = EVP_PKEY_verify_recover_init(ctx); break; case EVP_PKEY_OP_ENCRYPT: rv = EVP_PKEY_encrypt_init(ctx); break; case EVP_PKEY_OP_DECRYPT: rv = EVP_PKEY_decrypt_init(ctx); break; case EVP_PKEY_OP_DERIVE: rv = EVP_PKEY_derive_init(ctx); break; } } if (rv <= 0) { EVP_PKEY_CTX_free(ctx); ctx = NULL; } end: OPENSSL_free(passin); return ctx; } static int setup_peer(EVP_PKEY_CTX *ctx, int peerform, const char *file, ENGINE *e) { EVP_PKEY *peer = NULL; ENGINE *engine = NULL; int ret; if (peerform == FORMAT_ENGINE) engine = e; peer = load_pubkey(file, peerform, 0, NULL, engine, "Peer Key"); if (peer == NULL) { BIO_printf(bio_err, "Error reading peer key %s\n", file); ERR_print_errors(bio_err); return 0; } ret = EVP_PKEY_derive_set_peer(ctx, peer); EVP_PKEY_free(peer); if (ret <= 0) ERR_print_errors(bio_err); return ret; } static int do_keyop(EVP_PKEY_CTX *ctx, int pkey_op, unsigned char *out, size_t *poutlen, const unsigned char *in, size_t inlen) { int rv = 0; switch (pkey_op) { case EVP_PKEY_OP_VERIFYRECOVER: rv = EVP_PKEY_verify_recover(ctx, out, poutlen, in, inlen); break; case EVP_PKEY_OP_SIGN: rv = EVP_PKEY_sign(ctx, out, poutlen, in, inlen); break; case EVP_PKEY_OP_ENCRYPT: rv = EVP_PKEY_encrypt(ctx, out, poutlen, in, inlen); break; case EVP_PKEY_OP_DECRYPT: rv = EVP_PKEY_decrypt(ctx, out, poutlen, in, inlen); break; case EVP_PKEY_OP_DERIVE: rv = EVP_PKEY_derive(ctx, out, poutlen); break; } return rv; } #define TBUF_MAXSIZE 2048 static int do_raw_keyop(int pkey_op, EVP_PKEY_CTX *ctx, const EVP_MD *md, EVP_PKEY *pkey, BIO *in, int filesize, unsigned char *sig, int siglen, unsigned char **out, size_t *poutlen) { int rv = 0; EVP_MD_CTX *mctx = NULL; unsigned char tbuf[TBUF_MAXSIZE]; unsigned char *mbuf = NULL; int buf_len = 0; if ((mctx = EVP_MD_CTX_new()) == NULL) { BIO_printf(bio_err, "Error: out of memory\n"); return rv; } EVP_MD_CTX_set_pkey_ctx(mctx, ctx); /* Some algorithms only support oneshot digests */ if (EVP_PKEY_id(pkey) == EVP_PKEY_ED25519 || EVP_PKEY_id(pkey) == EVP_PKEY_ED448) { if (filesize < 0) { BIO_printf(bio_err, "Error: unable to determine file size for oneshot operation\n"); return rv; } mbuf = app_malloc(filesize, "oneshot sign/verify buffer"); switch(pkey_op) { case EVP_PKEY_OP_VERIFY: if (EVP_DigestVerifyInit(mctx, NULL, md, NULL, pkey) != 1) goto end; buf_len = BIO_read(in, mbuf, filesize); if (buf_len != filesize) { BIO_printf(bio_err, "Error reading raw input data\n"); goto end; } rv = EVP_DigestVerify(mctx, sig, (size_t)siglen, mbuf, buf_len); break; case EVP_PKEY_OP_SIGN: if (EVP_DigestSignInit(mctx, NULL, md, NULL, pkey) != 1) goto end; buf_len = BIO_read(in, mbuf, filesize); if (buf_len != filesize) { BIO_printf(bio_err, "Error reading raw input data\n"); goto end; } rv = EVP_DigestSign(mctx, NULL, poutlen, mbuf, buf_len); if (rv == 1 && out != NULL) { *out = app_malloc(*poutlen, "buffer output"); rv = EVP_DigestSign(mctx, *out, poutlen, mbuf, buf_len); } break; } OPENSSL_free(mbuf); goto end; } switch(pkey_op) { case EVP_PKEY_OP_VERIFY: if (EVP_DigestVerifyInit(mctx, NULL, md, NULL, pkey) != 1) goto end; for (;;) { buf_len = BIO_read(in, tbuf, TBUF_MAXSIZE); if (buf_len == 0) break; if (buf_len < 0) { BIO_printf(bio_err, "Error reading raw input data\n"); goto end; } rv = EVP_DigestVerifyUpdate(mctx, tbuf, (size_t)buf_len); if (rv != 1) { BIO_printf(bio_err, "Error verifying raw input data\n"); goto end; } } rv = EVP_DigestVerifyFinal(mctx, sig, (size_t)siglen); break; case EVP_PKEY_OP_SIGN: if (EVP_DigestSignInit(mctx, NULL, md, NULL, pkey) != 1) goto end; for (;;) { buf_len = BIO_read(in, tbuf, TBUF_MAXSIZE); if (buf_len == 0) break; if (buf_len < 0) { BIO_printf(bio_err, "Error reading raw input data\n"); goto end; } rv = EVP_DigestSignUpdate(mctx, tbuf, (size_t)buf_len); if (rv != 1) { BIO_printf(bio_err, "Error signing raw input data\n"); goto end; } } rv = EVP_DigestSignFinal(mctx, NULL, poutlen); if (rv == 1 && out != NULL) { *out = app_malloc(*poutlen, "buffer output"); rv = EVP_DigestSignFinal(mctx, *out, poutlen); } break; } end: EVP_MD_CTX_free(mctx); return rv; }