| /* |
| * Copyright 1999-2016 The OpenSSL Project Authors. All Rights Reserved. |
| * |
| * Licensed under the OpenSSL license (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 |
| */ |
| |
| // The following is ported from the OpenSSL-1.1.0b library. The implementations |
| // of the functions are for the most part the same except where mentioned in special |
| // comments. Explicit casts were also added to bypass compilation errors. |
| |
| #include "kudu/security/x509_check_host.h" |
| |
| #include <openssl/asn1.h> |
| #include <openssl/crypto.h> |
| #include <openssl/obj_mac.h> |
| #include <openssl/ssl.h> |
| #include <openssl/x509.h> |
| #include <openssl/x509v3.h> |
| #include <strings.h> |
| |
| #include <cstring> |
| |
| // Ported from include/openssl/crypto.h from OpenSSL-1.1.0b |
| // Modifed to use __FILE__ and __LINE__ instead of OPENSSL_FILE and OPENSSL_LINE. |
| # define OPENSSL_strndup(str, n) \ |
| CRYPTO_strndup(str, n, __FILE__, __LINE__) |
| |
| // Ported from crypto/o_str.c from OpenSSL-1.1.0b. |
| // Modified to use strnlen() instead of OPENSSL_strnlen() |
| char *CRYPTO_strndup(const char *str, size_t s, const char* file, int line) |
| { |
| size_t maxlen; |
| char *ret; |
| |
| if (str == NULL) |
| return NULL; |
| |
| maxlen = strnlen(str, s); |
| |
| ret = (char*)CRYPTO_malloc(maxlen + 1, file, line); |
| if (ret) { |
| memcpy(ret, str, maxlen); |
| ret[maxlen] = '\0'; |
| } |
| return ret; |
| } |
| |
| // The remaining code is ported form crypto/x509v3/v3_utl.c |
| |
| typedef int (*equal_fn) (const unsigned char *pattern, size_t pattern_len, |
| const unsigned char *subject, size_t subject_len, |
| unsigned int flags); |
| |
| /* Skip pattern prefix to match "wildcard" subject */ |
| static void skip_prefix(const unsigned char **p, size_t *plen, |
| size_t subject_len, |
| unsigned int flags) |
| { |
| const unsigned char *pattern = *p; |
| size_t pattern_len = *plen; |
| |
| /* |
| * If subject starts with a leading '.' followed by more octets, and |
| * pattern is longer, compare just an equal-length suffix with the |
| * full subject (starting at the '.'), provided the prefix contains |
| * no NULs. |
| */ |
| if ((flags & _X509_CHECK_FLAG_DOT_SUBDOMAINS) == 0) |
| return; |
| |
| while (pattern_len > subject_len && *pattern) { |
| if ((flags & X509_CHECK_FLAG_SINGLE_LABEL_SUBDOMAINS) && |
| *pattern == '.') |
| break; |
| ++pattern; |
| --pattern_len; |
| } |
| |
| /* Skip if entire prefix acceptable */ |
| if (pattern_len == subject_len) { |
| *p = pattern; |
| *plen = pattern_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, |
| unsigned int flags) |
| { |
| skip_prefix(&pattern, &pattern_len, subject_len, flags); |
| 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, |
| unsigned int flags) |
| { |
| skip_prefix(&pattern, &pattern_len, subject_len, flags); |
| 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, |
| unsigned int unused_flags) |
| { |
| 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, 0)) |
| return 0; |
| break; |
| } |
| } |
| if (i == 0) |
| i = a_len; |
| return equal_case(a, i, b, i, 0); |
| } |
| |
| /* |
| * 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, |
| unsigned int flags) |
| { |
| const unsigned char *wildcard_start; |
| const unsigned char *wildcard_end; |
| const unsigned char *p; |
| int allow_multi = 0; |
| int allow_idna = 0; |
| |
| if (subject_len < prefix_len + suffix_len) |
| return 0; |
| if (!equal_nocase(prefix, prefix_len, subject, prefix_len, flags)) |
| return 0; |
| wildcard_start = subject + prefix_len; |
| wildcard_end = subject + (subject_len - suffix_len); |
| if (!equal_nocase(wildcard_end, suffix_len, suffix, suffix_len, flags)) |
| return 0; |
| /* |
| * If the wildcard makes up the entire first label, it must match at |
| * least one character. |
| */ |
| if (prefix_len == 0 && *suffix == '.') { |
| if (wildcard_start == wildcard_end) |
| return 0; |
| allow_idna = 1; |
| if (flags & X509_CHECK_FLAG_MULTI_LABEL_WILDCARDS) |
| allow_multi = 1; |
| } |
| /* IDNA labels cannot match partial wildcards */ |
| if (!allow_idna && |
| subject_len >= 4 && strncasecmp((char *)subject, "xn--", 4) == 0) |
| return 0; |
| /* The wildcard may match a literal '*' */ |
| if (wildcard_end == wildcard_start + 1 && *wildcard_start == '*') |
| return 1; |
| /* |
| * Check that the part matched by the wildcard contains only |
| * permitted characters and only matches a single label unless |
| * allow_multi is set. |
| */ |
| for (p = wildcard_start; p != wildcard_end; ++p) |
| if (!(('0' <= *p && *p <= '9') || |
| ('A' <= *p && *p <= 'Z') || |
| ('a' <= *p && *p <= 'z') || |
| *p == '-' || (allow_multi && *p == '.'))) |
| return 0; |
| return 1; |
| } |
| |
| #define LABEL_START (1 << 0) |
| #define LABEL_END (1 << 1) |
| #define LABEL_HYPHEN (1 << 2) |
| #define LABEL_IDNA (1 << 3) |
| |
| static const unsigned char *valid_star(const unsigned char *p, size_t len, |
| unsigned int flags) |
| { |
| const unsigned char *star = 0; |
| size_t i; |
| int state = LABEL_START; |
| int dots = 0; |
| for (i = 0; i < len; ++i) { |
| /* |
| * Locate first and only legal wildcard, either at the start |
| * or end of a non-IDNA first and not final label. |
| */ |
| if (p[i] == '*') { |
| int atstart = (state & LABEL_START); |
| int atend = (i == len - 1 || p[i + 1] == '.'); |
| /*- |
| * At most one wildcard per pattern. |
| * No wildcards in IDNA labels. |
| * No wildcards after the first label. |
| */ |
| if (star != NULL || (state & LABEL_IDNA) != 0 || dots) |
| return NULL; |
| /* Only full-label '*.example.com' wildcards? */ |
| if ((flags & X509_CHECK_FLAG_NO_PARTIAL_WILDCARDS) |
| && (!atstart || !atend)) |
| return NULL; |
| /* No 'foo*bar' wildcards */ |
| if (!atstart && !atend) |
| return NULL; |
| star = &p[i]; |
| state &= ~LABEL_START; |
| } else if (('a' <= p[i] && p[i] <= 'z') |
| || ('A' <= p[i] && p[i] <= 'Z') |
| || ('0' <= p[i] && p[i] <= '9')) { |
| if ((state & LABEL_START) != 0 |
| && len - i >= 4 && strncasecmp((char *)&p[i], "xn--", 4) == 0) |
| state |= LABEL_IDNA; |
| state &= ~(LABEL_HYPHEN | LABEL_START); |
| } else if (p[i] == '.') { |
| if ((state & (LABEL_HYPHEN | LABEL_START)) != 0) |
| return NULL; |
| state = LABEL_START; |
| ++dots; |
| } else if (p[i] == '-') { |
| /* no domain/subdomain starts with '-' */ |
| if ((state & LABEL_START) != 0) |
| return NULL; |
| state |= LABEL_HYPHEN; |
| } else |
| return NULL; |
| } |
| |
| /* |
| * The final label must not end in a hyphen or ".", and |
| * there must be at least two dots after the star. |
| */ |
| if ((state & (LABEL_START | LABEL_HYPHEN)) != 0 || dots < 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, |
| unsigned int flags) |
| { |
| const unsigned char *star = NULL; |
| |
| /* |
| * Subject names starting with '.' can only match a wildcard pattern |
| * via a subject sub-domain pattern suffix match. |
| */ |
| if (!(subject_len > 1 && subject[0] == '.')) |
| star = valid_star(pattern, pattern_len, flags); |
| if (star == NULL) |
| return equal_nocase(pattern, pattern_len, |
| subject, subject_len, flags); |
| return wildcard_match(pattern, star - pattern, |
| star + 1, (pattern + pattern_len) - star - 1, |
| subject, subject_len, flags); |
| } |
| |
| /* |
| * 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(const ASN1_STRING *a, int cmp_type, equal_fn equal, |
| unsigned int flags, const char *b, size_t blen, |
| char **peername) |
| { |
| int rv = 0; |
| |
| if (!a->data || !a->length) |
| return 0; |
| if (cmp_type > 0) { |
| if (cmp_type != a->type) |
| return 0; |
| if (cmp_type == V_ASN1_IA5STRING) |
| rv = equal(a->data, a->length, (unsigned char *)b, blen, flags); |
| else if (a->length == (int)blen && !memcmp(a->data, b, blen)) |
| rv = 1; |
| if (rv > 0 && peername) |
| *peername = OPENSSL_strndup((char *)a->data, a->length); |
| } else { |
| int astrlen; |
| unsigned char *astr; |
| astrlen = ASN1_STRING_to_UTF8(&astr, (ASN1_STRING*)a); |
| if (astrlen < 0) { |
| /* |
| * -1 could be an internal malloc failure or a decoding error from |
| * malformed input; we can't distinguish. |
| */ |
| return -1; |
| } |
| rv = equal(astr, astrlen, (unsigned char *)b, blen, flags); |
| if (rv > 0 && peername) |
| *peername = OPENSSL_strndup((char *)astr, astrlen); |
| //*peername = strndup((char *)astr, astrlen); |
| OPENSSL_free(astr); |
| } |
| return rv; |
| } |
| |
| static int do_x509_check(X509 *x, const char *chk, size_t chklen, |
| unsigned int flags, int check_type, char **peername) |
| { |
| GENERAL_NAMES *gens = NULL; |
| X509_NAME *name = NULL; |
| int i; |
| int cnid = NID_undef; |
| int alt_type; |
| int san_present = 0; |
| int rv = 0; |
| equal_fn equal; |
| |
| /* See below, this flag is internal-only */ |
| flags &= ~_X509_CHECK_FLAG_DOT_SUBDOMAINS; |
| 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; |
| /* Implicit client-side DNS sub-domain pattern */ |
| if (chklen > 1 && chk[0] == '.') |
| flags |= _X509_CHECK_FLAG_DOT_SUBDOMAINS; |
| alt_type = V_ASN1_IA5STRING; |
| if (flags & X509_CHECK_FLAG_NO_WILDCARDS) |
| equal = equal_nocase; |
| else |
| equal = equal_wildcard; |
| } else { |
| alt_type = V_ASN1_OCTET_STRING; |
| equal = equal_case; |
| } |
| |
| if (chklen == 0) |
| chklen = strlen(chk); |
| |
| gens = (GENERAL_NAMES*)X509_get_ext_d2i(x, NID_subject_alt_name, NULL, NULL); |
| if (gens) { |
| 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; |
| san_present = 1; |
| if (check_type == GEN_EMAIL) |
| cstr = gen->d.rfc822Name; |
| else if (check_type == GEN_DNS) |
| cstr = gen->d.dNSName; |
| else |
| cstr = gen->d.iPAddress; |
| /* Positive on success, negative on error! */ |
| if ((rv = do_check_string(cstr, alt_type, equal, flags, |
| chk, chklen, peername)) != 0) |
| break; |
| } |
| GENERAL_NAMES_free(gens); |
| if (rv != 0) |
| return rv; |
| if (san_present && !(flags & X509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT)) |
| return 0; |
| } |
| |
| /* We're done if CN-ID is not pertinent */ |
| if (cnid == NID_undef || (flags & X509_CHECK_FLAG_NEVER_CHECK_SUBJECT)) |
| return 0; |
| |
| i = -1; |
| name = X509_get_subject_name(x); |
| while ((i = X509_NAME_get_index_by_NID(name, cnid, i)) >= 0) { |
| const X509_NAME_ENTRY *ne = X509_NAME_get_entry(name, i); |
| const ASN1_STRING *str = X509_NAME_ENTRY_get_data((X509_NAME_ENTRY*)ne); |
| |
| /* Positive on success, negative on error! */ |
| if ((rv = do_check_string(str, -1, equal, flags, |
| chk, chklen, peername)) != 0) |
| return rv; |
| } |
| return 0; |
| } |
| |
| int X509_check_host(X509 *x, const char *chk, size_t chklen, |
| unsigned int flags, char **peername) |
| { |
| if (chk == NULL) |
| return -2; |
| /* |
| * Embedded NULs are disallowed, except as the last character of a |
| * string of length 2 or more (tolerate caller including terminating |
| * NUL in string length). |
| */ |
| if (chklen == 0) |
| chklen = strlen(chk); |
| else if (memchr(chk, '\0', chklen > 1 ? chklen - 1 : chklen)) |
| return -2; |
| if (chklen > 1 && chk[chklen - 1] == '\0') |
| --chklen; |
| return do_x509_check(x, chk, chklen, flags, GEN_DNS, peername); |
| } |
