diff options
Diffstat (limited to 'crypto/x509v3/v3_ncons.c')
| -rw-r--r-- | crypto/x509v3/v3_ncons.c | 312 |
1 files changed, 299 insertions, 13 deletions
diff --git a/crypto/x509v3/v3_ncons.c b/crypto/x509v3/v3_ncons.c index 624fe7e..a01dc64 100644 --- a/crypto/x509v3/v3_ncons.c +++ b/crypto/x509v3/v3_ncons.c @@ -63,15 +63,22 @@ #include <openssl/conf.h> #include <openssl/x509v3.h> -static void *v2i_NAME_CONSTRAINTS(X509V3_EXT_METHOD *method, - X509V3_CTX *ctx, STACK_OF(CONF_VALUE) *nval); -static int i2r_NAME_CONSTRAINTS(X509V3_EXT_METHOD *method, +static void *v2i_NAME_CONSTRAINTS(const X509V3_EXT_METHOD *method, + X509V3_CTX *ctx, STACK_OF(CONF_VALUE) *nval); +static int i2r_NAME_CONSTRAINTS(const X509V3_EXT_METHOD *method, void *a, BIO *bp, int ind); -static int do_i2r_name_constraints(X509V3_EXT_METHOD *method, - STACK_OF(GENERAL_SUBTREE) *trees, - BIO *bp, int ind, char *name); +static int do_i2r_name_constraints(const X509V3_EXT_METHOD *method, + STACK_OF(GENERAL_SUBTREE) *trees, + BIO *bp, int ind, char *name); static int print_nc_ipadd(BIO *bp, ASN1_OCTET_STRING *ip); +static int nc_match(GENERAL_NAME *gen, NAME_CONSTRAINTS *nc); +static int nc_match_single(GENERAL_NAME *sub, GENERAL_NAME *gen); +static int nc_dn(X509_NAME *sub, X509_NAME *nm); +static int nc_dns(ASN1_IA5STRING *sub, ASN1_IA5STRING *dns); +static int nc_email(ASN1_IA5STRING *sub, ASN1_IA5STRING *eml); +static int nc_uri(ASN1_IA5STRING *uri, ASN1_IA5STRING *base); + const X509V3_EXT_METHOD v3_name_constraints = { NID_name_constraints, 0, ASN1_ITEM_ref(NAME_CONSTRAINTS), @@ -99,8 +106,8 @@ ASN1_SEQUENCE(NAME_CONSTRAINTS) = { IMPLEMENT_ASN1_ALLOC_FUNCTIONS(GENERAL_SUBTREE) IMPLEMENT_ASN1_ALLOC_FUNCTIONS(NAME_CONSTRAINTS) -static void *v2i_NAME_CONSTRAINTS(X509V3_EXT_METHOD *method, - X509V3_CTX *ctx, STACK_OF(CONF_VALUE) *nval) +static void *v2i_NAME_CONSTRAINTS(const X509V3_EXT_METHOD *method, + X509V3_CTX *ctx, STACK_OF(CONF_VALUE) *nval) { int i; CONF_VALUE tval, *val; @@ -155,8 +162,8 @@ static void *v2i_NAME_CONSTRAINTS(X509V3_EXT_METHOD *method, -static int i2r_NAME_CONSTRAINTS(X509V3_EXT_METHOD *method, - void *a, BIO *bp, int ind) +static int i2r_NAME_CONSTRAINTS(const X509V3_EXT_METHOD *method, void *a, + BIO *bp, int ind) { NAME_CONSTRAINTS *ncons = a; do_i2r_name_constraints(method, ncons->permittedSubtrees, @@ -166,9 +173,9 @@ static int i2r_NAME_CONSTRAINTS(X509V3_EXT_METHOD *method, return 1; } -static int do_i2r_name_constraints(X509V3_EXT_METHOD *method, - STACK_OF(GENERAL_SUBTREE) *trees, - BIO *bp, int ind, char *name) +static int do_i2r_name_constraints(const X509V3_EXT_METHOD *method, + STACK_OF(GENERAL_SUBTREE) *trees, + BIO *bp, int ind, char *name) { GENERAL_SUBTREE *tree; int i; @@ -217,3 +224,282 @@ static int print_nc_ipadd(BIO *bp, ASN1_OCTET_STRING *ip) return 1; } +/* Check a certificate conforms to a specified set of constraints. + * Return values: + * X509_V_OK: All constraints obeyed. + * X509_V_ERR_PERMITTED_VIOLATION: Permitted subtree violation. + * X509_V_ERR_EXCLUDED_VIOLATION: Excluded subtree violation. + * X509_V_ERR_SUBTREE_MINMAX: Min or max values present and matching type. + * X509_V_ERR_UNSUPPORTED_CONSTRAINT_TYPE: Unsupported constraint type. + * X509_V_ERR_UNSUPPORTED_CONSTRAINT_SYNTAX: bad unsupported constraint syntax. + * X509_V_ERR_UNSUPPORTED_NAME_SYNTAX: bad or unsupported syntax of name + + */ + +int NAME_CONSTRAINTS_check(X509 *x, NAME_CONSTRAINTS *nc) + { + int r, i; + X509_NAME *nm; + + nm = X509_get_subject_name(x); + + if (X509_NAME_entry_count(nm) > 0) + { + GENERAL_NAME gntmp; + gntmp.type = GEN_DIRNAME; + gntmp.d.directoryName = nm; + + r = nc_match(&gntmp, nc); + + if (r != X509_V_OK) + return r; + + gntmp.type = GEN_EMAIL; + + + /* Process any email address attributes in subject name */ + + for (i = -1;;) + { + X509_NAME_ENTRY *ne; + i = X509_NAME_get_index_by_NID(nm, + NID_pkcs9_emailAddress, + i); + if (i == -1) + break; + ne = X509_NAME_get_entry(nm, i); + gntmp.d.rfc822Name = X509_NAME_ENTRY_get_data(ne); + if (gntmp.d.rfc822Name->type != V_ASN1_IA5STRING) + return X509_V_ERR_UNSUPPORTED_NAME_SYNTAX; + + r = nc_match(&gntmp, nc); + + if (r != X509_V_OK) + return r; + } + + } + + for (i = 0; i < sk_GENERAL_NAME_num(x->altname); i++) + { + GENERAL_NAME *gen = sk_GENERAL_NAME_value(x->altname, i); + r = nc_match(gen, nc); + if (r != X509_V_OK) + return r; + } + + return X509_V_OK; + + } + +static int nc_match(GENERAL_NAME *gen, NAME_CONSTRAINTS *nc) + { + GENERAL_SUBTREE *sub; + int i, r, match = 0; + + /* Permitted subtrees: if any subtrees exist of matching the type + * at least one subtree must match. + */ + + for (i = 0; i < sk_GENERAL_SUBTREE_num(nc->permittedSubtrees); i++) + { + sub = sk_GENERAL_SUBTREE_value(nc->permittedSubtrees, i); + if (gen->type != sub->base->type) + continue; + if (sub->minimum || sub->maximum) + return X509_V_ERR_SUBTREE_MINMAX; + /* If we already have a match don't bother trying any more */ + if (match == 2) + continue; + if (match == 0) + match = 1; + r = nc_match_single(gen, sub->base); + if (r == X509_V_OK) + match = 2; + else if (r != X509_V_ERR_PERMITTED_VIOLATION) + return r; + } + + if (match == 1) + return X509_V_ERR_PERMITTED_VIOLATION; + + /* Excluded subtrees: must not match any of these */ + + for (i = 0; i < sk_GENERAL_SUBTREE_num(nc->excludedSubtrees); i++) + { + sub = sk_GENERAL_SUBTREE_value(nc->excludedSubtrees, i); + if (gen->type != sub->base->type) + continue; + if (sub->minimum || sub->maximum) + return X509_V_ERR_SUBTREE_MINMAX; + + r = nc_match_single(gen, sub->base); + if (r == X509_V_OK) + return X509_V_ERR_EXCLUDED_VIOLATION; + else if (r != X509_V_ERR_PERMITTED_VIOLATION) + return r; + + } + + return X509_V_OK; + + } + +static int nc_match_single(GENERAL_NAME *gen, GENERAL_NAME *base) + { + switch(base->type) + { + case GEN_DIRNAME: + return nc_dn(gen->d.directoryName, base->d.directoryName); + + case GEN_DNS: + return nc_dns(gen->d.dNSName, base->d.dNSName); + + case GEN_EMAIL: + return nc_email(gen->d.rfc822Name, base->d.rfc822Name); + + case GEN_URI: + return nc_uri(gen->d.uniformResourceIdentifier, + base->d.uniformResourceIdentifier); + + default: + return X509_V_ERR_UNSUPPORTED_CONSTRAINT_TYPE; + } + + } + +/* directoryName name constraint matching. + * The canonical encoding of X509_NAME makes this comparison easy. It is + * matched if the subtree is a subset of the name. + */ + +static int nc_dn(X509_NAME *nm, X509_NAME *base) + { + /* Ensure canonical encodings are up to date. */ + if (nm->modified && i2d_X509_NAME(nm, NULL) < 0) + return X509_V_ERR_OUT_OF_MEM; + if (base->modified && i2d_X509_NAME(base, NULL) < 0) + return X509_V_ERR_OUT_OF_MEM; + if (base->canon_enclen > nm->canon_enclen) + return X509_V_ERR_PERMITTED_VIOLATION; + if (memcmp(base->canon_enc, nm->canon_enc, base->canon_enclen)) + return X509_V_ERR_PERMITTED_VIOLATION; + return X509_V_OK; + } + +static int nc_dns(ASN1_IA5STRING *dns, ASN1_IA5STRING *base) + { + char *baseptr = (char *)base->data; + char *dnsptr = (char *)dns->data; + /* Empty matches everything */ + if (!*baseptr) + return X509_V_OK; + /* Otherwise can add zero or more components on the left so + * compare RHS and if dns is longer and expect '.' as preceding + * character. + */ + if (dns->length > base->length) + { + dnsptr += dns->length - base->length; + if (dnsptr[-1] != '.') + return X509_V_ERR_PERMITTED_VIOLATION; + } + + if (strcasecmp(baseptr, dnsptr)) + return X509_V_ERR_PERMITTED_VIOLATION; + + return X509_V_OK; + + } + +static int nc_email(ASN1_IA5STRING *eml, ASN1_IA5STRING *base) + { + const char *baseptr = (char *)base->data; + const char *emlptr = (char *)eml->data; + + const char *baseat = strchr(baseptr, '@'); + const char *emlat = strchr(emlptr, '@'); + if (!emlat) + return X509_V_ERR_UNSUPPORTED_NAME_SYNTAX; + /* Special case: inital '.' is RHS match */ + if (!baseat && (*baseptr == '.')) + { + if (eml->length > base->length) + { + emlptr += eml->length - base->length; + if (!strcasecmp(baseptr, emlptr)) + return X509_V_OK; + } + return X509_V_ERR_PERMITTED_VIOLATION; + } + + /* If we have anything before '@' match local part */ + + if (baseat) + { + if (baseat != baseptr) + { + if ((baseat - baseptr) != (emlat - emlptr)) + return X509_V_ERR_PERMITTED_VIOLATION; + /* Case sensitive match of local part */ + if (strncmp(baseptr, emlptr, emlat - emlptr)) + return X509_V_ERR_PERMITTED_VIOLATION; + } + /* Position base after '@' */ + baseptr = baseat + 1; + } + emlptr = emlat + 1; + /* Just have hostname left to match: case insensitive */ + if (strcasecmp(baseptr, emlptr)) + return X509_V_ERR_PERMITTED_VIOLATION; + + return X509_V_OK; + + } + +static int nc_uri(ASN1_IA5STRING *uri, ASN1_IA5STRING *base) + { + const char *baseptr = (char *)base->data; + const char *hostptr = (char *)uri->data; + const char *p = strchr(hostptr, ':'); + int hostlen; + /* Check for foo:// and skip past it */ + if (!p || (p[1] != '/') || (p[2] != '/')) + return X509_V_ERR_UNSUPPORTED_NAME_SYNTAX; + hostptr = p + 3; + + /* Determine length of hostname part of URI */ + + /* Look for a port indicator as end of hostname first */ + + p = strchr(hostptr, ':'); + /* Otherwise look for trailing slash */ + if (!p) + p = strchr(hostptr, '/'); + + if (!p) + hostlen = strlen(hostptr); + else + hostlen = p - hostptr; + + if (hostlen == 0) + return X509_V_ERR_UNSUPPORTED_NAME_SYNTAX; + + /* Special case: inital '.' is RHS match */ + if (*baseptr == '.') + { + if (hostlen > base->length) + { + p = hostptr + hostlen - base->length; + if (!strncasecmp(p, baseptr, base->length)) + return X509_V_OK; + } + return X509_V_ERR_PERMITTED_VIOLATION; + } + + if ((base->length != (int)hostlen) || strncasecmp(hostptr, baseptr, hostlen)) + return X509_V_ERR_PERMITTED_VIOLATION; + + return X509_V_OK; + + } |
