/* * Copyright 1999-2022 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 */ #include #include "internal/cryptlib.h" #include #include "crypto/x509.h" static int tr_cmp(const X509_TRUST *const *a, const X509_TRUST *const *b); static void trtable_free(X509_TRUST *p); static int trust_1oidany(X509_TRUST *trust, X509 *x, int flags); static int trust_1oid(X509_TRUST *trust, X509 *x, int flags); static int trust_compat(X509_TRUST *trust, X509 *x, int flags); static int obj_trust(int id, X509 *x, int flags); static int (*default_trust) (int id, X509 *x, int flags) = obj_trust; /* * WARNING: the following table should be kept in order of trust and without * any gaps so we can just subtract the minimum trust value to get an index * into the table */ static X509_TRUST trstandard[] = { {X509_TRUST_COMPAT, 0, trust_compat, "compatible", 0, NULL}, {X509_TRUST_SSL_CLIENT, 0, trust_1oidany, "SSL Client", NID_client_auth, NULL}, {X509_TRUST_SSL_SERVER, 0, trust_1oidany, "SSL Server", NID_server_auth, NULL}, {X509_TRUST_EMAIL, 0, trust_1oidany, "S/MIME email", NID_email_protect, NULL}, {X509_TRUST_OBJECT_SIGN, 0, trust_1oidany, "Object Signer", NID_code_sign, NULL}, {X509_TRUST_OCSP_SIGN, 0, trust_1oid, "OCSP responder", NID_OCSP_sign, NULL}, {X509_TRUST_OCSP_REQUEST, 0, trust_1oid, "OCSP request", NID_ad_OCSP, NULL}, {X509_TRUST_TSA, 0, trust_1oidany, "TSA server", NID_time_stamp, NULL} }; #define X509_TRUST_COUNT OSSL_NELEM(trstandard) static STACK_OF(X509_TRUST) *trtable = NULL; static int tr_cmp(const X509_TRUST *const *a, const X509_TRUST *const *b) { return (*a)->trust - (*b)->trust; } int (*X509_TRUST_set_default(int (*trust) (int, X509 *, int))) (int, X509 *, int) { int (*oldtrust) (int, X509 *, int); oldtrust = default_trust; default_trust = trust; return oldtrust; } /* Returns X509_TRUST_TRUSTED, X509_TRUST_REJECTED, or X509_TRUST_UNTRUSTED */ int X509_check_trust(X509 *x, int id, int flags) { X509_TRUST *pt; int idx; /* We get this as a default value */ if (id == X509_TRUST_DEFAULT) return obj_trust(NID_anyExtendedKeyUsage, x, flags | X509_TRUST_DO_SS_COMPAT); idx = X509_TRUST_get_by_id(id); if (idx < 0) return default_trust(id, x, flags); pt = X509_TRUST_get0(idx); return pt->check_trust(pt, x, flags); } int X509_TRUST_get_count(void) { if (!trtable) return X509_TRUST_COUNT; return sk_X509_TRUST_num(trtable) + X509_TRUST_COUNT; } X509_TRUST *X509_TRUST_get0(int idx) { if (idx < 0) return NULL; if (idx < (int)X509_TRUST_COUNT) return trstandard + idx; return sk_X509_TRUST_value(trtable, idx - X509_TRUST_COUNT); } int X509_TRUST_get_by_id(int id) { X509_TRUST tmp; int idx; if ((id >= X509_TRUST_MIN) && (id <= X509_TRUST_MAX)) return id - X509_TRUST_MIN; if (trtable == NULL) return -1; tmp.trust = id; idx = sk_X509_TRUST_find(trtable, &tmp); if (idx < 0) return -1; return idx + X509_TRUST_COUNT; } int X509_TRUST_set(int *t, int trust) { if (X509_TRUST_get_by_id(trust) < 0) { ERR_raise(ERR_LIB_X509, X509_R_INVALID_TRUST); return 0; } *t = trust; return 1; } int X509_TRUST_add(int id, int flags, int (*ck) (X509_TRUST *, X509 *, int), const char *name, int arg1, void *arg2) { int idx; X509_TRUST *trtmp; /* * This is set according to what we change: application can't set it */ flags &= ~X509_TRUST_DYNAMIC; /* This will always be set for application modified trust entries */ flags |= X509_TRUST_DYNAMIC_NAME; /* Get existing entry if any */ idx = X509_TRUST_get_by_id(id); /* Need a new entry */ if (idx < 0) { if ((trtmp = OPENSSL_malloc(sizeof(*trtmp))) == NULL) return 0; trtmp->flags = X509_TRUST_DYNAMIC; } else trtmp = X509_TRUST_get0(idx); /* OPENSSL_free existing name if dynamic */ if (trtmp->flags & X509_TRUST_DYNAMIC_NAME) OPENSSL_free(trtmp->name); /* dup supplied name */ if ((trtmp->name = OPENSSL_strdup(name)) == NULL) goto err; /* Keep the dynamic flag of existing entry */ trtmp->flags &= X509_TRUST_DYNAMIC; /* Set all other flags */ trtmp->flags |= flags; trtmp->trust = id; trtmp->check_trust = ck; trtmp->arg1 = arg1; trtmp->arg2 = arg2; /* If its a new entry manage the dynamic table */ if (idx < 0) { if (trtable == NULL && (trtable = sk_X509_TRUST_new(tr_cmp)) == NULL) { ERR_raise(ERR_LIB_X509, ERR_R_CRYPTO_LIB); goto err; } if (!sk_X509_TRUST_push(trtable, trtmp)) { ERR_raise(ERR_LIB_X509, ERR_R_CRYPTO_LIB); goto err; } } return 1; err: if (idx < 0) { OPENSSL_free(trtmp->name); OPENSSL_free(trtmp); } return 0; } static void trtable_free(X509_TRUST *p) { if (p == NULL) return; if (p->flags & X509_TRUST_DYNAMIC) { if (p->flags & X509_TRUST_DYNAMIC_NAME) OPENSSL_free(p->name); OPENSSL_free(p); } } void X509_TRUST_cleanup(void) { sk_X509_TRUST_pop_free(trtable, trtable_free); trtable = NULL; } int X509_TRUST_get_flags(const X509_TRUST *xp) { return xp->flags; } char *X509_TRUST_get0_name(const X509_TRUST *xp) { return xp->name; } int X509_TRUST_get_trust(const X509_TRUST *xp) { return xp->trust; } static int trust_1oidany(X509_TRUST *trust, X509 *x, int flags) { /* * Declare the chain verified if the desired trust OID is not rejected in * any auxiliary trust info for this certificate, and the OID is either * expressly trusted, or else either "anyEKU" is trusted, or the * certificate is self-signed and X509_TRUST_NO_SS_COMPAT is not set. */ flags |= X509_TRUST_DO_SS_COMPAT | X509_TRUST_OK_ANY_EKU; return obj_trust(trust->arg1, x, flags); } static int trust_1oid(X509_TRUST *trust, X509 *x, int flags) { /* * Declare the chain verified only if the desired trust OID is not * rejected and is expressly trusted. Neither "anyEKU" nor "compat" * trust in self-signed certificates apply. */ flags &= ~(X509_TRUST_DO_SS_COMPAT | X509_TRUST_OK_ANY_EKU); return obj_trust(trust->arg1, x, flags); } static int trust_compat(X509_TRUST *trust, X509 *x, int flags) { /* Call for side-effect of setting EXFLAG_SS for self-signed-certs */ if (X509_check_purpose(x, -1, 0) != 1) return X509_TRUST_UNTRUSTED; if ((flags & X509_TRUST_NO_SS_COMPAT) == 0 && (x->ex_flags & EXFLAG_SS)) return X509_TRUST_TRUSTED; else return X509_TRUST_UNTRUSTED; } static int obj_trust(int id, X509 *x, int flags) { X509_CERT_AUX *ax = x->aux; int i; if (ax != NULL && ax->reject != NULL) { for (i = 0; i < sk_ASN1_OBJECT_num(ax->reject); i++) { ASN1_OBJECT *obj = sk_ASN1_OBJECT_value(ax->reject, i); int nid = OBJ_obj2nid(obj); if (nid == id || (nid == NID_anyExtendedKeyUsage && (flags & X509_TRUST_OK_ANY_EKU))) return X509_TRUST_REJECTED; } } if (ax != NULL && ax->trust != NULL) { for (i = 0; i < sk_ASN1_OBJECT_num(ax->trust); i++) { ASN1_OBJECT *obj = sk_ASN1_OBJECT_value(ax->trust, i); int nid = OBJ_obj2nid(obj); if (nid == id || (nid == NID_anyExtendedKeyUsage && (flags & X509_TRUST_OK_ANY_EKU))) return X509_TRUST_TRUSTED; } /* * Reject when explicit trust EKU are set and none match. * * Returning untrusted is enough for for full chains that end in * self-signed roots, because when explicit trust is specified it * suppresses the default blanket trust of self-signed objects. * * But for partial chains, this is not enough, because absent a similar * trust-self-signed policy, non matching EKUs are indistinguishable * from lack of EKU constraints. * * Therefore, failure to match any trusted purpose must trigger an * explicit reject. */ return X509_TRUST_REJECTED; } if ((flags & X509_TRUST_DO_SS_COMPAT) == 0) return X509_TRUST_UNTRUSTED; /* * Not rejected, and there is no list of accepted uses, try compat. */ return trust_compat(NULL, x, flags); }