diff options
author | Dr. Stephen Henson <steve@openssl.org> | 2012-12-19 15:01:59 +0000 |
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committer | Dr. Stephen Henson <steve@openssl.org> | 2012-12-19 15:01:59 +0000 |
commit | 45da1efcdb822d8ff992e13d5a1600fa62c96c6d (patch) | |
tree | c997ce2acf968ce1a4d9f9f23dafbedfda7aba4d /crypto/x509v3 | |
parent | 54a0076e94dc411e3569bb069dd6d53f95787575 (diff) |
Backport X509 hostname, IP address and email checking code from HEAD.
Diffstat (limited to 'crypto/x509v3')
-rw-r--r-- | crypto/x509v3/Makefile | 2 | ||||
-rw-r--r-- | crypto/x509v3/v3_utl.c | 299 | ||||
-rw-r--r-- | crypto/x509v3/x509v3.h | 14 |
3 files changed, 314 insertions, 1 deletions
diff --git a/crypto/x509v3/Makefile b/crypto/x509v3/Makefile index 556ef351bf..3ac379a7fa 100644 --- a/crypto/x509v3/Makefile +++ b/crypto/x509v3/Makefile @@ -13,7 +13,7 @@ AR= ar r CFLAGS= $(INCLUDES) $(CFLAG) GENERAL=Makefile README -TEST= +TEST=v3nametest.c APPS= LIB=$(TOP)/libcrypto.a diff --git a/crypto/x509v3/v3_utl.c b/crypto/x509v3/v3_utl.c index e030234540..de43c2fb3b 100644 --- a/crypto/x509v3/v3_utl.c +++ b/crypto/x509v3/v3_utl.c @@ -568,6 +568,305 @@ void X509_email_free(STACK_OF(OPENSSL_STRING) *sk) sk_OPENSSL_STRING_pop_free(sk, str_free); } +typedef int (*equal_fn)(const unsigned char *pattern, size_t pattern_len, + const unsigned char *subject, size_t subject_len); + +/* Compare while ASCII ignoring case. */ +static int equal_nocase(const unsigned char *pattern, size_t pattern_len, + const unsigned char *subject, size_t subject_len) + { + if (pattern_len != subject_len) + return 0; + while (pattern_len) + { + unsigned char l = *pattern; + unsigned char r = *subject; + /* The pattern must not contain NUL characters. */ + if (l == 0) + return 0; + if (l != r) + { + if ('A' <= l && l <= 'Z') + l = (l - 'A') + 'a'; + if ('A' <= r && r <= 'Z') + r = (r - 'A') + 'a'; + if (l != r) + return 0; + } + ++pattern; + ++subject; + --pattern_len; + } + return 1; + } + +/* Compare using memcmp. */ +static int equal_case(const unsigned char *pattern, size_t pattern_len, + const unsigned char *subject, size_t subject_len) +{ + /* The pattern must not contain NUL characters. */ + if (memchr(pattern, '\0', pattern_len) != NULL) + return 0; + if (pattern_len != subject_len) + return 0; + return !memcmp(pattern, subject, pattern_len); +} + +/* RFC 5280, section 7.5, requires that only the domain is compared in + a case-insensitive manner. */ +static int equal_email(const unsigned char *a, size_t a_len, + const unsigned char *b, size_t b_len) + { + size_t i = a_len; + if (a_len != b_len) + return 0; + /* We search backwards for the '@' character, so that we do + not have to deal with quoted local-parts. The domain part + is compared in a case-insensitive manner. */ + while (i > 0) + { + --i; + if (a[i] == '@' || b[i] == '@') + { + if (!equal_nocase(a + i, a_len - i, + b + i, a_len - i)) + return 0; + break; + } + } + if (i == 0) + i = a_len; + return equal_case(a, i, b, i); + } + +/* Compare the prefix and suffix with the subject, and check that the + characters in-between are valid. */ +static int wildcard_match(const unsigned char *prefix, size_t prefix_len, + const unsigned char *suffix, size_t suffix_len, + const unsigned char *subject, size_t subject_len) + { + const unsigned char *wildcard_start; + const unsigned char *wildcard_end; + const unsigned char *p; + if (subject_len < prefix_len + suffix_len) + return 0; + if (!equal_nocase(prefix, prefix_len, subject, prefix_len)) + return 0; + wildcard_start = subject + prefix_len; + wildcard_end = subject + (subject_len - suffix_len); + if (!equal_nocase(wildcard_end, suffix_len, suffix, suffix_len)) + return 0; + /* The wildcard must match at least one character. */ + if (wildcard_start == wildcard_end) + return 0; + /* Check that the part matched by the wildcard contains only + permitted characters and only matches a single label. */ + for (p = wildcard_start; p != wildcard_end; ++p) + if (!(('0' <= *p && *p <= '9') || + ('A' <= *p && *p <= 'Z') || + ('a' <= *p && *p <= 'z') || + *p == '-')) + return 0; + return 1; + } + +/* Checks if the memory region consistens of [0-9A-Za-z.-]. */ +static int valid_domain_characters(const unsigned char *p, size_t len) + { + while (len) + { + if (!(('0' <= *p && *p <= '9') || + ('A' <= *p && *p <= 'Z') || + ('a' <= *p && *p <= 'z') || + *p == '-' || *p == '.')) + return 0; + ++p; + --len; + } + return 1; + } + +/* Find the '*' in a wildcard pattern. If no such character is found + or the pattern is otherwise invalid, returns NULL. */ +static const unsigned char *wildcard_find_star(const unsigned char *pattern, + size_t pattern_len) + { + const unsigned char *star = memchr(pattern, '*', pattern_len); + size_t dot_count = 0; + const unsigned char *suffix_start; + size_t suffix_length; + if (star == NULL) + return NULL; + suffix_start = star + 1; + suffix_length = (pattern + pattern_len) - (star + 1); + if (!(valid_domain_characters(pattern, star - pattern) && + valid_domain_characters(suffix_start, suffix_length))) + return NULL; + /* Check that the suffix matches at least two labels. */ + while (suffix_length) + { + if (*suffix_start == '.') + ++dot_count; + ++suffix_start; + --suffix_length; + } + if (dot_count < 2) + return NULL; + return star; + } + +/* Compare using wildcards. */ +static int equal_wildcard(const unsigned char *pattern, size_t pattern_len, + const unsigned char *subject, size_t subject_len) + { + const unsigned char *star = wildcard_find_star(pattern, pattern_len); + if (star == NULL) + return equal_nocase(pattern, pattern_len, + subject, subject_len); + return wildcard_match(pattern, star - pattern, + star + 1, (pattern + pattern_len) - star - 1, + subject, subject_len); + } + +/* Compare an ASN1_STRING to a supplied string. If they match + * return 1. If cmp_type > 0 only compare if string matches the + * type, otherwise convert it to UTF8. + */ + +static int do_check_string(ASN1_STRING *a, int cmp_type, equal_fn equal, + const unsigned char *b, size_t blen) + { + if (!a->data || !a->length) + return 0; + if (cmp_type > 0) + { + if (cmp_type != a->type) + return 0; + if (cmp_type == V_ASN1_IA5STRING) + return equal(a->data, a->length, b, blen); + if (a->length == (int)blen && !memcmp(a->data, b, blen)) + return 1; + else + return 0; + } + else + { + int astrlen, rv; + unsigned char *astr; + astrlen = ASN1_STRING_to_UTF8(&astr, a); + if (astrlen < 0) + return -1; + rv = equal(astr, astrlen, b, blen); + OPENSSL_free(astr); + return rv; + } + } + +static int do_x509_check(X509 *x, const unsigned char *chk, size_t chklen, + unsigned int flags, int check_type) + { + GENERAL_NAMES *gens = NULL; + X509_NAME *name = NULL; + int i; + int cnid; + int alt_type; + equal_fn equal; + if (check_type == GEN_EMAIL) + { + cnid = NID_pkcs9_emailAddress; + alt_type = V_ASN1_IA5STRING; + equal = equal_email; + } + else if (check_type == GEN_DNS) + { + cnid = NID_commonName; + alt_type = V_ASN1_IA5STRING; + if (flags & X509_CHECK_FLAG_NO_WILDCARDS) + equal = equal_nocase; + else + equal = equal_wildcard; + } + else + { + cnid = 0; + alt_type = V_ASN1_OCTET_STRING; + equal = equal_case; + } + + if (chklen == 0) + chklen = strlen((const char *)chk); + + gens = X509_get_ext_d2i(x, NID_subject_alt_name, NULL, NULL); + if (gens) + { + int rv = 0; + for (i = 0; i < sk_GENERAL_NAME_num(gens); i++) + { + GENERAL_NAME *gen; + ASN1_STRING *cstr; + gen = sk_GENERAL_NAME_value(gens, i); + if(gen->type != check_type) + continue; + if (check_type == GEN_EMAIL) + cstr = gen->d.rfc822Name; + else if (check_type == GEN_DNS) + cstr = gen->d.dNSName; + else + cstr = gen->d.iPAddress; + if (do_check_string(cstr, alt_type, equal, chk, chklen)) + { + rv = 1; + break; + } + } + GENERAL_NAMES_free(gens); + if (rv) + return 1; + if (!(flags & X509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT) || !cnid) + return 0; + } + i = -1; + name = X509_get_subject_name(x); + while((i = X509_NAME_get_index_by_NID(name, cnid, i)) >= 0) + { + X509_NAME_ENTRY *ne; + ASN1_STRING *str; + ne = X509_NAME_get_entry(name, i); + str = X509_NAME_ENTRY_get_data(ne); + if (do_check_string(str, -1, equal, chk, chklen)) + return 1; + } + return 0; + } + +int X509_check_host(X509 *x, const unsigned char *chk, size_t chklen, + unsigned int flags) + { + return do_x509_check(x, chk, chklen, flags, GEN_DNS); + } + +int X509_check_email(X509 *x, const unsigned char *chk, size_t chklen, + unsigned int flags) + { + return do_x509_check(x, chk, chklen, flags, GEN_EMAIL); + } + +int X509_check_ip(X509 *x, const unsigned char *chk, size_t chklen, + unsigned int flags) + { + return do_x509_check(x, chk, chklen, flags, GEN_IPADD); + } + +int X509_check_ip_asc(X509 *x, const char *ipasc, unsigned int flags) + { + unsigned char ipout[16]; + int iplen; + iplen = a2i_ipadd(ipout, ipasc); + if (iplen == 0) + return -2; + return do_x509_check(x, ipout, (size_t)iplen, flags, GEN_IPADD); + } + /* Convert IP addresses both IPv4 and IPv6 into an * OCTET STRING compatible with RFC3280. */ diff --git a/crypto/x509v3/x509v3.h b/crypto/x509v3/x509v3.h index 34909475ae..e5cce114a3 100644 --- a/crypto/x509v3/x509v3.h +++ b/crypto/x509v3/x509v3.h @@ -698,6 +698,20 @@ STACK_OF(OPENSSL_STRING) *X509_get1_email(X509 *x); STACK_OF(OPENSSL_STRING) *X509_REQ_get1_email(X509_REQ *x); void X509_email_free(STACK_OF(OPENSSL_STRING) *sk); STACK_OF(OPENSSL_STRING) *X509_get1_ocsp(X509 *x); +/* Flags for X509_check_* functions */ + +/* Always check subject name for host match even if subject alt names present */ +#define X509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT 0x1 +/* Disable wild-card matching for dnsName fields and common name. */ +#define X509_CHECK_FLAG_NO_WILDCARDS 0x2 + +int X509_check_host(X509 *x, const unsigned char *chk, size_t chklen, + unsigned int flags); +int X509_check_email(X509 *x, const unsigned char *chk, size_t chklen, + unsigned int flags); +int X509_check_ip(X509 *x, const unsigned char *chk, size_t chklen, + unsigned int flags); +int X509_check_ip_asc(X509 *x, const char *ipasc, unsigned int flags); ASN1_OCTET_STRING *a2i_IPADDRESS(const char *ipasc); ASN1_OCTET_STRING *a2i_IPADDRESS_NC(const char *ipasc); |