/* Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ /* _ _ * _ __ ___ ___ __| | ___ ___| | mod_ssl * | '_ ` _ \ / _ \ / _` | / __/ __| | Apache Interface to OpenSSL * | | | | | | (_) | (_| | \__ \__ \ | * |_| |_| |_|\___/ \__,_|___|___/___/_| * |_____| * ssl_util_ssl.c * Additional Utility Functions for OpenSSL */ #include "ssl_private.h" /* _________________________________________________________________ ** ** Additional High-Level Functions for OpenSSL ** _________________________________________________________________ */ /* we initialize this index at startup time * and never write to it at request time, * so this static is thread safe. * also note that OpenSSL increments at static variable when * SSL_get_ex_new_index() is called, so we _must_ do this at startup. */ static int app_data2_idx = -1; void modssl_init_app_data2_idx(void) { int i; if (app_data2_idx > -1) { return; } /* we _do_ need to call this twice */ for (i = 0; i <= 1; i++) { app_data2_idx = SSL_get_ex_new_index(0, "Second Application Data for SSL", NULL, NULL, NULL); } } void *modssl_get_app_data2(SSL *ssl) { return (void *)SSL_get_ex_data(ssl, app_data2_idx); } void modssl_set_app_data2(SSL *ssl, void *arg) { SSL_set_ex_data(ssl, app_data2_idx, (char *)arg); return; } /* _________________________________________________________________ ** ** High-Level Private Key Loading ** _________________________________________________________________ */ EVP_PKEY *modssl_read_privatekey(const char* filename, EVP_PKEY **key, pem_password_cb *cb, void *s) { EVP_PKEY *rc; BIO *bioS; BIO *bioF; /* 1. try PEM (= DER+Base64+headers) */ if ((bioS=BIO_new_file(filename, "r")) == NULL) return NULL; rc = PEM_read_bio_PrivateKey(bioS, key, cb, s); BIO_free(bioS); if (rc == NULL) { /* 2. try DER+Base64 */ if ((bioS = BIO_new_file(filename, "r")) == NULL) return NULL; if ((bioF = BIO_new(BIO_f_base64())) == NULL) { BIO_free(bioS); return NULL; } bioS = BIO_push(bioF, bioS); rc = d2i_PrivateKey_bio(bioS, NULL); BIO_free_all(bioS); if (rc == NULL) { /* 3. try plain DER */ if ((bioS = BIO_new_file(filename, "r")) == NULL) return NULL; rc = d2i_PrivateKey_bio(bioS, NULL); BIO_free(bioS); } } if (rc != NULL && key != NULL) { if (*key != NULL) EVP_PKEY_free(*key); *key = rc; } return rc; } /* _________________________________________________________________ ** ** Smart shutdown ** _________________________________________________________________ */ int modssl_smart_shutdown(SSL *ssl) { int i; int rc; int flush; /* * Repeat the calls, because SSL_shutdown internally dispatches through a * little state machine. Usually only one or two interation should be * needed, so we restrict the total number of restrictions in order to * avoid process hangs in case the client played bad with the socket * connection and OpenSSL cannot recognize it. */ rc = 0; flush = !(SSL_get_shutdown(ssl) & SSL_SENT_SHUTDOWN); for (i = 0; i < 4 /* max 2x pending + 2x data = 4 */; i++) { rc = SSL_shutdown(ssl); if (rc >= 0 && flush && (SSL_get_shutdown(ssl) & SSL_SENT_SHUTDOWN)) { /* Once the close notity is sent through the output filters, * ensure it is flushed through the socket. */ if (BIO_flush(SSL_get_wbio(ssl)) <= 0) { rc = -1; break; } flush = 0; } if (rc != 0) break; } return rc; } /* _________________________________________________________________ ** ** Certificate Checks ** _________________________________________________________________ */ /* retrieve basic constraints ingredients */ BOOL modssl_X509_getBC(X509 *cert, int *ca, int *pathlen) { BASIC_CONSTRAINTS *bc; BIGNUM *bn = NULL; char *cp; bc = X509_get_ext_d2i(cert, NID_basic_constraints, NULL, NULL); if (bc == NULL) return FALSE; *ca = bc->ca; *pathlen = -1 /* unlimited */; if (bc->pathlen != NULL) { if ((bn = ASN1_INTEGER_to_BN(bc->pathlen, NULL)) == NULL) { BASIC_CONSTRAINTS_free(bc); return FALSE; } if ((cp = BN_bn2dec(bn)) == NULL) { BN_free(bn); BASIC_CONSTRAINTS_free(bc); return FALSE; } *pathlen = atoi(cp); OPENSSL_free(cp); BN_free(bn); } BASIC_CONSTRAINTS_free(bc); return TRUE; } /* convert an ASN.1 string to a UTF-8 string (escaping control characters) */ static char *asn1_string_to_utf8(apr_pool_t *p, ASN1_STRING *asn1str) { char *result = NULL; BIO *bio; int len; if ((bio = BIO_new(BIO_s_mem())) == NULL) return NULL; ASN1_STRING_print_ex(bio, asn1str, ASN1_STRFLGS_ESC_CTRL| ASN1_STRFLGS_UTF8_CONVERT); len = BIO_pending(bio); if (len > 0) { result = apr_palloc(p, len+1); len = BIO_read(bio, result, len); result[len] = NUL; } BIO_free(bio); return result; } /* convert a NAME_ENTRY to UTF8 string */ char *modssl_X509_NAME_ENTRY_to_string(apr_pool_t *p, X509_NAME_ENTRY *xsne) { char *result = asn1_string_to_utf8(p, X509_NAME_ENTRY_get_data(xsne)); ap_xlate_proto_from_ascii(result, len); return result; } /* * convert an X509_NAME to an RFC 2253 formatted string, optionally truncated * to maxlen characters (specify a maxlen of 0 for no length limit) */ char *modssl_X509_NAME_to_string(apr_pool_t *p, X509_NAME *dn, int maxlen) { char *result = NULL; BIO *bio; int len; if ((bio = BIO_new(BIO_s_mem())) == NULL) return NULL; X509_NAME_print_ex(bio, dn, 0, XN_FLAG_RFC2253); len = BIO_pending(bio); if (len > 0) { result = apr_palloc(p, (maxlen > 0) ? maxlen+1 : len+1); if (maxlen > 0 && maxlen < len) { len = BIO_read(bio, result, maxlen); if (maxlen > 2) { /* insert trailing ellipsis if there's enough space */ apr_snprintf(result + maxlen - 3, 4, "..."); } } else { len = BIO_read(bio, result, len); } result[len] = NUL; } BIO_free(bio); return result; } /* * Return an array of subjectAltName entries of type "type". If idx is -1, * return all entries of the given type, otherwise return an array consisting * of the n-th occurrence of that type only. Currently supported types: * GEN_EMAIL (rfc822Name) * GEN_DNS (dNSName) */ BOOL modssl_X509_getSAN(apr_pool_t *p, X509 *x509, int type, int idx, apr_array_header_t **entries) { STACK_OF(GENERAL_NAME) *names; if (!x509 || (type < GEN_OTHERNAME) || (type > GEN_RID) || (idx < -1) || !(*entries = apr_array_make(p, 0, sizeof(char *)))) { *entries = NULL; return FALSE; } if ((names = X509_get_ext_d2i(x509, NID_subject_alt_name, NULL, NULL))) { int i, n = 0; GENERAL_NAME *name; const char *utf8str; for (i = 0; i < sk_GENERAL_NAME_num(names); i++) { name = sk_GENERAL_NAME_value(names, i); if (name->type == type) { if ((idx == -1) || (n == idx)) { switch (type) { case GEN_EMAIL: case GEN_DNS: utf8str = asn1_string_to_utf8(p, name->d.ia5); if (utf8str) { APR_ARRAY_PUSH(*entries, const char *) = utf8str; } break; default: /* * Not implemented right now: * GEN_OTHERNAME (otherName) * GEN_X400 (x400Address) * GEN_DIRNAME (directoryName) * GEN_EDIPARTY (ediPartyName) * GEN_URI (uniformResourceIdentifier) * GEN_IPADD (iPAddress) * GEN_RID (registeredID) */ break; } } if ((idx != -1) && (n++ > idx)) break; } } sk_GENERAL_NAME_pop_free(names, GENERAL_NAME_free); } return apr_is_empty_array(*entries) ? FALSE : TRUE; } /* return an array of (RFC 6125 coined) DNS-IDs and CN-IDs in a certificate */ static BOOL getIDs(apr_pool_t *p, X509 *x509, apr_array_header_t **ids) { X509_NAME *subj; int i = -1; /* First, the DNS-IDs (dNSName entries in the subjectAltName extension) */ if (!x509 || (modssl_X509_getSAN(p, x509, GEN_DNS, -1, ids) == FALSE && !*ids)) { *ids = NULL; return FALSE; } /* Second, the CN-IDs (commonName attributes in the subject DN) */ subj = X509_get_subject_name(x509); while ((i = X509_NAME_get_index_by_NID(subj, NID_commonName, i)) != -1) { APR_ARRAY_PUSH(*ids, const char *) = modssl_X509_NAME_ENTRY_to_string(p, X509_NAME_get_entry(subj, i)); } return apr_is_empty_array(*ids) ? FALSE : TRUE; } /* * Check if a certificate matches for a particular name, by iterating over its * DNS-IDs and CN-IDs (RFC 6125), optionally with basic wildcard matching. * If server_rec is non-NULL, some (debug/trace) logging is enabled. */ BOOL modssl_X509_match_name(apr_pool_t *p, X509 *x509, const char *name, BOOL allow_wildcard, server_rec *s) { BOOL matched = FALSE; apr_array_header_t *ids; /* * At some day in the future, this might be replaced with X509_check_host() * (available in OpenSSL 1.0.2 and later), but two points should be noted: * 1) wildcard matching in X509_check_host() might yield different * results (by default, it supports a broader set of patterns, e.g. * wildcards in non-initial positions); * 2) we lose the option of logging each DNS- and CN-ID (until a match * is found). */ if (getIDs(p, x509, &ids)) { const char *cp; int i; char **id = (char **)ids->elts; BOOL is_wildcard; for (i = 0; i < ids->nelts; i++) { if (!id[i]) continue; /* * Determine if it is a wildcard ID - we're restrictive * in the sense that we require the wildcard character to be * THE left-most label (i.e., the ID must start with "*.") */ is_wildcard = (*id[i] == '*' && *(id[i]+1) == '.') ? TRUE : FALSE; /* * If the ID includes a wildcard character (and the caller is * allowing wildcards), check if it matches for the left-most * DNS label - i.e., the wildcard character is not allowed * to match a dot. Otherwise, try a simple string compare. */ if ((allow_wildcard == TRUE && is_wildcard == TRUE && (cp = ap_strchr_c(name, '.')) && !strcasecmp(id[i]+1, cp)) || !strcasecmp(id[i], name)) { matched = TRUE; } if (s) { ap_log_error(APLOG_MARK, APLOG_TRACE3, 0, s, "[%s] modssl_X509_match_name: expecting name '%s', " "%smatched by ID '%s'", (mySrvConfig(s))->vhost_id, name, matched == TRUE ? "" : "NOT ", id[i]); } if (matched == TRUE) { break; } } } if (s) { ssl_log_xerror(SSLLOG_MARK, APLOG_DEBUG, 0, p, s, x509, APLOGNO(02412) "[%s] Cert %s for name '%s'", (mySrvConfig(s))->vhost_id, matched == TRUE ? "matches" : "does not match", name); } return matched; } /* _________________________________________________________________ ** ** Custom (EC)DH parameter support ** _________________________________________________________________ */ DH *ssl_dh_GetParamFromFile(const char *file) { DH *dh = NULL; BIO *bio; if ((bio = BIO_new_file(file, "r")) == NULL) return NULL; dh = PEM_read_bio_DHparams(bio, NULL, NULL, NULL); BIO_free(bio); return (dh); } #ifdef HAVE_ECC EC_GROUP *ssl_ec_GetParamFromFile(const char *file) { EC_GROUP *group = NULL; BIO *bio; if ((bio = BIO_new_file(file, "r")) == NULL) return NULL; group = PEM_read_bio_ECPKParameters(bio, NULL, NULL, NULL); BIO_free(bio); return (group); } #endif /* _________________________________________________________________ ** ** Session Stuff ** _________________________________________________________________ */ char *modssl_SSL_SESSION_id2sz(unsigned char *id, int idlen, char *str, int strsize) { if (idlen > SSL_MAX_SSL_SESSION_ID_LENGTH) idlen = SSL_MAX_SSL_SESSION_ID_LENGTH; /* We must ensure not to process more than what would fit in the * destination buffer, including terminating NULL */ if (idlen > (strsize-1) / 2) idlen = (strsize-1) / 2; ap_bin2hex(id, idlen, str); return str; }