diff options
Diffstat (limited to 'Modules/_hashopenssl.c')
| -rw-r--r-- | Modules/_hashopenssl.c | 318 |
1 files changed, 196 insertions, 122 deletions
diff --git a/Modules/_hashopenssl.c b/Modules/_hashopenssl.c index 50cf3c57491..ce9603d5db8 100644 --- a/Modules/_hashopenssl.c +++ b/Modules/_hashopenssl.c @@ -311,8 +311,9 @@ class _hashlib.HMAC "HMACobject *" "((_hashlibstate *)PyModule_GetState(module)) /* Set an exception of given type using the given OpenSSL error code. */ static void -set_ssl_exception_from_errcode(PyObject *exc, unsigned long errcode) +set_ssl_exception_from_errcode(PyObject *exc_type, unsigned long errcode) { + assert(exc_type != NULL); assert(errcode != 0); /* ERR_ERROR_STRING(3) ensures that the messages below are ASCII */ @@ -321,13 +322,29 @@ set_ssl_exception_from_errcode(PyObject *exc, unsigned long errcode) const char *reason = ERR_reason_error_string(errcode); if (lib && func) { - PyErr_Format(exc, "[%s: %s] %s", lib, func, reason); + PyErr_Format(exc_type, "[%s: %s] %s", lib, func, reason); } else if (lib) { - PyErr_Format(exc, "[%s] %s", lib, reason); + PyErr_Format(exc_type, "[%s] %s", lib, reason); } else { - PyErr_SetString(exc, reason); + PyErr_SetString(exc_type, reason); + } +} + +/* + * Get an appropriate exception type for the given OpenSSL error code. + * + * The exception type depends on the error code reason. + */ +static PyObject * +get_smart_ssl_exception_type(unsigned long errcode, PyObject *default_exc_type) +{ + switch (ERR_GET_REASON(errcode)) { + case ERR_R_MALLOC_FAILURE: + return PyExc_MemoryError; + default: + return default_exc_type; } } @@ -335,36 +352,83 @@ set_ssl_exception_from_errcode(PyObject *exc, unsigned long errcode) * Set an exception of given type. * * By default, the exception's message is constructed by using the last SSL - * error that occurred. If no error occurred, the 'fallback_format' is used - * to create a C-style formatted fallback message. + * error that occurred. If no error occurred, the 'fallback_message' is used + * to create an exception message. */ static void -raise_ssl_error(PyObject *exc, const char *fallback_format, ...) +raise_ssl_error(PyObject *exc_type, const char *fallback_message) +{ + assert(fallback_message != NULL); + unsigned long errcode = ERR_peek_last_error(); + if (errcode) { + ERR_clear_error(); + set_ssl_exception_from_errcode(exc_type, errcode); + } + else { + PyErr_SetString(exc_type, fallback_message); + } +} + +/* Same as raise_ssl_error() but with a C-style formatted message. */ +static void +raise_ssl_error_f(PyObject *exc_type, const char *fallback_format, ...) { assert(fallback_format != NULL); unsigned long errcode = ERR_peek_last_error(); if (errcode) { ERR_clear_error(); - set_ssl_exception_from_errcode(exc, errcode); + set_ssl_exception_from_errcode(exc_type, errcode); } else { va_list vargs; va_start(vargs, fallback_format); - PyErr_FormatV(exc, fallback_format, vargs); + PyErr_FormatV(exc_type, fallback_format, vargs); + va_end(vargs); + } +} + +/* Same as raise_ssl_error_f() with smart exception types. */ +static void +raise_smart_ssl_error_f(PyObject *exc_type, const char *fallback_format, ...) +{ + unsigned long errcode = ERR_peek_last_error(); + if (errcode) { + ERR_clear_error(); + exc_type = get_smart_ssl_exception_type(errcode, exc_type); + set_ssl_exception_from_errcode(exc_type, errcode); + } + else { + va_list vargs; + va_start(vargs, fallback_format); + PyErr_FormatV(exc_type, fallback_format, vargs); va_end(vargs); } } /* - * Set an exception with a generic default message after an error occurred. - * - * It can also be used without previous calls to SSL built-in functions, - * in which case a generic error message is provided. + * Raise a ValueError with a default message after an error occurred. + * It can also be used without previous calls to SSL built-in functions. */ static inline void -notify_ssl_error_occurred(void) +notify_ssl_error_occurred(const char *message) +{ + raise_ssl_error(PyExc_ValueError, message); +} + +/* Same as notify_ssl_error_occurred() for failed OpenSSL functions. */ +static inline void +notify_ssl_error_occurred_in(const char *funcname) { - raise_ssl_error(PyExc_ValueError, "no reason supplied"); + raise_ssl_error_f(PyExc_ValueError, + "error in OpenSSL function %s()", funcname); +} + +/* Same as notify_ssl_error_occurred_in() with smart exception types. */ +static inline void +notify_smart_ssl_error_occurred_in(const char *funcname) +{ + raise_smart_ssl_error_f(PyExc_ValueError, + "error in OpenSSL function %s()", funcname); } /* LCOV_EXCL_STOP */ @@ -408,16 +472,19 @@ get_asn1_utf8name_by_nid(int nid) // In OpenSSL 3.0 and later, OBJ_nid*() are thread-safe and may raise. assert(ERR_peek_last_error() != 0); if (ERR_GET_REASON(ERR_peek_last_error()) != OBJ_R_UNKNOWN_NID) { - notify_ssl_error_occurred(); - return NULL; + goto error; } // fallback to short name and unconditionally propagate errors name = OBJ_nid2sn(nid); if (name == NULL) { - raise_ssl_error(PyExc_ValueError, "cannot resolve NID %d", nid); + goto error; } } return name; + +error: + raise_ssl_error_f(PyExc_ValueError, "cannot resolve NID %d", nid); + return NULL; } /* @@ -449,8 +516,7 @@ static PY_EVP_MD * get_openssl_evp_md_by_utf8name(PyObject *module, const char *name, Py_hash_type py_ht) { - PY_EVP_MD *digest = NULL; - PY_EVP_MD *other_digest = NULL; + PY_EVP_MD *digest = NULL, *other_digest = NULL; _hashlibstate *state = get_hashlib_state(module); py_hashentry_t *entry = (py_hashentry_t *)_Py_hashtable_get( state->hashtable, (const void*)name @@ -484,15 +550,16 @@ get_openssl_evp_md_by_utf8name(PyObject *module, const char *name, #endif } break; + default: + goto invalid_hash_type; } // if another thread same thing at same time make sure we got same ptr assert(other_digest == NULL || other_digest == digest); - if (digest != NULL) { - if (other_digest == NULL) { - PY_EVP_MD_up_ref(digest); - } + if (digest != NULL && other_digest == NULL) { + PY_EVP_MD_up_ref(digest); } - } else { + } + else { // Fall back for looking up an unindexed OpenSSL specific name. switch (py_ht) { case Py_ht_evp: @@ -503,14 +570,21 @@ get_openssl_evp_md_by_utf8name(PyObject *module, const char *name, case Py_ht_evp_nosecurity: digest = PY_EVP_MD_fetch(name, "-fips"); break; + default: + goto invalid_hash_type; } } if (digest == NULL) { - raise_ssl_error(state->unsupported_digestmod_error, - "unsupported hash type %s", name); + raise_ssl_error_f(state->unsupported_digestmod_error, + "unsupported digest name: %s", name); return NULL; } return digest; + +invalid_hash_type: + assert(digest == NULL); + PyErr_Format(PyExc_SystemError, "unsupported hash type %d", py_ht); + return NULL; } /* @@ -556,6 +630,22 @@ get_openssl_evp_md(PyObject *module, PyObject *digestmod, Py_hash_type py_ht) return get_openssl_evp_md_by_utf8name(module, name, py_ht); } +// --- OpenSSL HASH wrappers -------------------------------------------------- + +/* Thin wrapper around EVP_MD_CTX_new() which sets an exception on failure. */ +static EVP_MD_CTX * +py_wrapper_EVP_MD_CTX_new(void) +{ + EVP_MD_CTX *ctx = EVP_MD_CTX_new(); + if (ctx == NULL) { + PyErr_NoMemory(); + return NULL; + } + return ctx; +} + +// --- HASH interface --------------------------------------------------------- + static HASHobject * new_hash_object(PyTypeObject *type) { @@ -565,10 +655,9 @@ new_hash_object(PyTypeObject *type) } HASHLIB_INIT_MUTEX(retval); - retval->ctx = EVP_MD_CTX_new(); + retval->ctx = py_wrapper_EVP_MD_CTX_new(); if (retval->ctx == NULL) { Py_DECREF(retval); - PyErr_NoMemory(); return NULL; } @@ -586,7 +675,7 @@ _hashlib_HASH_hash(HASHobject *self, const void *vp, Py_ssize_t len) else process = Py_SAFE_DOWNCAST(len, Py_ssize_t, unsigned int); if (!EVP_DigestUpdate(self->ctx, (const void*)cp, process)) { - notify_ssl_error_occurred(); + notify_ssl_error_occurred_in(Py_STRINGIFY(EVP_DigestUpdate)); return -1; } len -= process; @@ -614,7 +703,11 @@ _hashlib_HASH_copy_locked(HASHobject *self, EVP_MD_CTX *new_ctx_p) ENTER_HASHLIB(self); result = EVP_MD_CTX_copy(new_ctx_p, self->ctx); LEAVE_HASHLIB(self); - return result; + if (result == 0) { + notify_smart_ssl_error_occurred_in(Py_STRINGIFY(EVP_MD_CTX_copy)); + return -1; + } + return 0; } /* External methods for a hash object */ @@ -634,14 +727,36 @@ _hashlib_HASH_copy_impl(HASHobject *self) if ((newobj = new_hash_object(Py_TYPE(self))) == NULL) return NULL; - if (!_hashlib_HASH_copy_locked(self, newobj->ctx)) { + if (_hashlib_HASH_copy_locked(self, newobj->ctx) < 0) { Py_DECREF(newobj); - notify_ssl_error_occurred(); return NULL; } return (PyObject *)newobj; } +static Py_ssize_t +_hashlib_HASH_digest_compute(HASHobject *self, unsigned char *digest) +{ + EVP_MD_CTX *ctx = py_wrapper_EVP_MD_CTX_new(); + if (ctx == NULL) { + return -1; + } + if (_hashlib_HASH_copy_locked(self, ctx) < 0) { + goto error; + } + Py_ssize_t digest_size = EVP_MD_CTX_size(ctx); + if (!EVP_DigestFinal(ctx, digest, NULL)) { + notify_ssl_error_occurred_in(Py_STRINGIFY(EVP_DigestFinal)); + goto error; + } + EVP_MD_CTX_free(ctx); + return digest_size; + +error: + EVP_MD_CTX_free(ctx); + return -1; +} + /*[clinic input] _hashlib.HASH.digest @@ -653,32 +768,8 @@ _hashlib_HASH_digest_impl(HASHobject *self) /*[clinic end generated code: output=3fc6f9671d712850 input=d8d528d6e50af0de]*/ { unsigned char digest[EVP_MAX_MD_SIZE]; - EVP_MD_CTX *temp_ctx; - PyObject *retval; - unsigned int digest_size; - - temp_ctx = EVP_MD_CTX_new(); - if (temp_ctx == NULL) { - PyErr_NoMemory(); - return NULL; - } - - if (!_hashlib_HASH_copy_locked(self, temp_ctx)) { - goto error; - } - digest_size = EVP_MD_CTX_size(temp_ctx); - if (!EVP_DigestFinal(temp_ctx, digest, NULL)) { - goto error; - } - - retval = PyBytes_FromStringAndSize((const char *)digest, digest_size); - EVP_MD_CTX_free(temp_ctx); - return retval; - -error: - EVP_MD_CTX_free(temp_ctx); - notify_ssl_error_occurred(); - return NULL; + Py_ssize_t n = _hashlib_HASH_digest_compute(self, digest); + return n < 0 ? NULL : PyBytes_FromStringAndSize((const char *)digest, n); } /*[clinic input] @@ -692,32 +783,8 @@ _hashlib_HASH_hexdigest_impl(HASHobject *self) /*[clinic end generated code: output=1b8e60d9711e7f4d input=ae7553f78f8372d8]*/ { unsigned char digest[EVP_MAX_MD_SIZE]; - EVP_MD_CTX *temp_ctx; - unsigned int digest_size; - - temp_ctx = EVP_MD_CTX_new(); - if (temp_ctx == NULL) { - PyErr_NoMemory(); - return NULL; - } - - /* Get the raw (binary) digest value */ - if (!_hashlib_HASH_copy_locked(self, temp_ctx)) { - goto error; - } - digest_size = EVP_MD_CTX_size(temp_ctx); - if (!EVP_DigestFinal(temp_ctx, digest, NULL)) { - goto error; - } - - EVP_MD_CTX_free(temp_ctx); - - return _Py_strhex((const char *)digest, (Py_ssize_t)digest_size); - -error: - EVP_MD_CTX_free(temp_ctx); - notify_ssl_error_occurred(); - return NULL; + Py_ssize_t n = _hashlib_HASH_digest_compute(self, digest); + return n < 0 ? NULL : _Py_strhex((const char *)digest, n); } /*[clinic input] @@ -788,7 +855,7 @@ _hashlib_HASH_get_name(PyObject *op, void *Py_UNUSED(closure)) HASHobject *self = HASHobject_CAST(op); const EVP_MD *md = EVP_MD_CTX_md(self->ctx); if (md == NULL) { - notify_ssl_error_occurred(); + notify_ssl_error_occurred("missing EVP_MD for HASH context"); return NULL; } const char *name = get_hashlib_utf8name_by_evp_md(md); @@ -877,20 +944,20 @@ _hashlib_HASHXOF_digest_impl(HASHobject *self, Py_ssize_t length) return NULL; } - temp_ctx = EVP_MD_CTX_new(); + temp_ctx = py_wrapper_EVP_MD_CTX_new(); if (temp_ctx == NULL) { Py_DECREF(retval); - PyErr_NoMemory(); return NULL; } - if (!_hashlib_HASH_copy_locked(self, temp_ctx)) { + if (_hashlib_HASH_copy_locked(self, temp_ctx) < 0) { goto error; } if (!EVP_DigestFinalXOF(temp_ctx, (unsigned char*)PyBytes_AS_STRING(retval), length)) { + notify_ssl_error_occurred_in(Py_STRINGIFY(EVP_DigestFinalXOF)); goto error; } @@ -900,7 +967,6 @@ _hashlib_HASHXOF_digest_impl(HASHobject *self, Py_ssize_t length) error: Py_DECREF(retval); EVP_MD_CTX_free(temp_ctx); - notify_ssl_error_occurred(); return NULL; } @@ -926,18 +992,18 @@ _hashlib_HASHXOF_hexdigest_impl(HASHobject *self, Py_ssize_t length) return NULL; } - temp_ctx = EVP_MD_CTX_new(); + temp_ctx = py_wrapper_EVP_MD_CTX_new(); if (temp_ctx == NULL) { PyMem_Free(digest); - PyErr_NoMemory(); return NULL; } /* Get the raw (binary) digest value */ - if (!_hashlib_HASH_copy_locked(self, temp_ctx)) { + if (_hashlib_HASH_copy_locked(self, temp_ctx) < 0) { goto error; } if (!EVP_DigestFinalXOF(temp_ctx, digest, length)) { + notify_ssl_error_occurred_in(Py_STRINGIFY(EVP_DigestFinalXOF)); goto error; } @@ -950,7 +1016,6 @@ _hashlib_HASHXOF_hexdigest_impl(HASHobject *self, Py_ssize_t length) error: PyMem_Free(digest); EVP_MD_CTX_free(temp_ctx); - notify_ssl_error_occurred(); return NULL; } @@ -1054,7 +1119,7 @@ _hashlib_HASH(PyObject *module, const char *digestname, PyObject *data_obj, int result = EVP_DigestInit_ex(self->ctx, digest, NULL); if (!result) { - notify_ssl_error_occurred(); + notify_ssl_error_occurred_in(Py_STRINGIFY(EVP_DigestInit_ex)); Py_CLEAR(self); goto exit; } @@ -1463,7 +1528,7 @@ pbkdf2_hmac_impl(PyObject *module, const char *hash_name, if (!retval) { Py_CLEAR(key_obj); - notify_ssl_error_occurred(); + notify_ssl_error_occurred_in(Py_STRINGIFY(PKCS5_PBKDF2_HMAC)); goto end; } @@ -1539,8 +1604,8 @@ _hashlib_scrypt_impl(PyObject *module, Py_buffer *password, Py_buffer *salt, /* let OpenSSL validate the rest */ retval = EVP_PBE_scrypt(NULL, 0, NULL, 0, n, r, p, maxmem, NULL, 0); if (!retval) { - raise_ssl_error(PyExc_ValueError, - "Invalid parameter combination for n, r, p, maxmem."); + notify_ssl_error_occurred( + "Invalid parameter combination for n, r, p, maxmem."); return NULL; } @@ -1561,7 +1626,7 @@ _hashlib_scrypt_impl(PyObject *module, Py_buffer *password, Py_buffer *salt, if (!retval) { Py_CLEAR(key_obj); - notify_ssl_error_occurred(); + notify_ssl_error_occurred_in(Py_STRINGIFY(EVP_PBE_scrypt)); return NULL; } return key_obj; @@ -1618,7 +1683,7 @@ _hashlib_hmac_singleshot_impl(PyObject *module, Py_buffer *key, PY_EVP_MD_free(evp); if (result == NULL) { - notify_ssl_error_occurred(); + notify_ssl_error_occurred_in(Py_STRINGIFY(HMAC)); return NULL; } return PyBytes_FromStringAndSize((const char*)md, md_len); @@ -1627,6 +1692,18 @@ _hashlib_hmac_singleshot_impl(PyObject *module, Py_buffer *key, /* OpenSSL-based HMAC implementation */ +/* Thin wrapper around HMAC_CTX_new() which sets an exception on failure. */ +static HMAC_CTX * +py_openssl_wrapper_HMAC_CTX_new(void) +{ + HMAC_CTX *ctx = HMAC_CTX_new(); + if (ctx == NULL) { + PyErr_NoMemory(); + return NULL; + } + return ctx; +} + static int _hmac_update(HMACobject*, PyObject*); static const EVP_MD * @@ -1634,7 +1711,7 @@ _hashlib_hmac_get_md(HMACobject *self) { const EVP_MD *md = HMAC_CTX_get_md(self->ctx); if (md == NULL) { - raise_ssl_error(PyExc_ValueError, "missing EVP_MD for HMAC context"); + notify_ssl_error_occurred("missing EVP_MD for HMAC context"); } return md; } @@ -1676,17 +1753,16 @@ _hashlib_hmac_new_impl(PyObject *module, Py_buffer *key, PyObject *msg_obj, return NULL; } - ctx = HMAC_CTX_new(); + ctx = py_openssl_wrapper_HMAC_CTX_new(); if (ctx == NULL) { PY_EVP_MD_free(digest); - PyErr_NoMemory(); goto error; } r = HMAC_Init_ex(ctx, key->buf, (int)key->len, digest, NULL /* impl */); PY_EVP_MD_free(digest); if (r == 0) { - notify_ssl_error_occurred(); + notify_ssl_error_occurred_in(Py_STRINGIFY(HMAC_Init_ex)); goto error; } @@ -1721,7 +1797,11 @@ locked_HMAC_CTX_copy(HMAC_CTX *new_ctx_p, HMACobject *self) ENTER_HASHLIB(self); result = HMAC_CTX_copy(new_ctx_p, self->ctx); LEAVE_HASHLIB(self); - return result; + if (result == 0) { + notify_smart_ssl_error_occurred_in(Py_STRINGIFY(HMAC_CTX_copy)); + return -1; + } + return 0; } /* returning 0 means that an error occurred and an exception is set */ @@ -1735,7 +1815,7 @@ _hashlib_hmac_digest_size(HMACobject *self) unsigned int digest_size = EVP_MD_size(md); assert(digest_size <= EVP_MAX_MD_SIZE); if (digest_size == 0) { - raise_ssl_error(PyExc_ValueError, "invalid digest size"); + notify_ssl_error_occurred("invalid digest size"); } return digest_size; } @@ -1768,7 +1848,7 @@ _hmac_update(HMACobject *self, PyObject *obj) PyBuffer_Release(&view); if (r == 0) { - notify_ssl_error_occurred(); + notify_ssl_error_occurred_in(Py_STRINGIFY(HMAC_Update)); return 0; } return 1; @@ -1786,13 +1866,12 @@ _hashlib_HMAC_copy_impl(HMACobject *self) { HMACobject *retval; - HMAC_CTX *ctx = HMAC_CTX_new(); + HMAC_CTX *ctx = py_openssl_wrapper_HMAC_CTX_new(); if (ctx == NULL) { - return PyErr_NoMemory(); + return NULL; } - if (!locked_HMAC_CTX_copy(ctx, self)) { + if (locked_HMAC_CTX_copy(ctx, self) < 0) { HMAC_CTX_free(ctx); - notify_ssl_error_occurred(); return NULL; } @@ -1854,20 +1933,18 @@ _hashlib_HMAC_update_impl(HMACobject *self, PyObject *msg) static int _hmac_digest(HMACobject *self, unsigned char *buf, unsigned int len) { - HMAC_CTX *temp_ctx = HMAC_CTX_new(); + HMAC_CTX *temp_ctx = py_openssl_wrapper_HMAC_CTX_new(); if (temp_ctx == NULL) { - (void)PyErr_NoMemory(); return 0; } - if (!locked_HMAC_CTX_copy(temp_ctx, self)) { + if (locked_HMAC_CTX_copy(temp_ctx, self) < 0) { HMAC_CTX_free(temp_ctx); - notify_ssl_error_occurred(); return 0; } int r = HMAC_Final(temp_ctx, buf, &len); HMAC_CTX_free(temp_ctx); if (r == 0) { - notify_ssl_error_occurred(); + notify_ssl_error_occurred_in(Py_STRINGIFY(HMAC_Final)); return 0; } return 1; @@ -2088,16 +2165,13 @@ _hashlib_get_fips_mode_impl(PyObject *module) #else ERR_clear_error(); int result = FIPS_mode(); - if (result == 0) { + if (result == 0 && ERR_peek_last_error()) { // "If the library was built without support of the FIPS Object Module, // then the function will return 0 with an error code of // CRYPTO_R_FIPS_MODE_NOT_SUPPORTED (0x0f06d065)." // But 0 is also a valid result value. - unsigned long errcode = ERR_peek_last_error(); - if (errcode) { - notify_ssl_error_occurred(); - return -1; - } + notify_ssl_error_occurred_in(Py_STRINGIFY(FIPS_mode)); + return -1; } return result; #endif |