diff options
Diffstat (limited to 'src/core/tsi/ssl_transport_security.c')
| -rw-r--r-- | src/core/tsi/ssl_transport_security.c | 1572 |
1 files changed, 1572 insertions, 0 deletions
diff --git a/src/core/tsi/ssl_transport_security.c b/src/core/tsi/ssl_transport_security.c new file mode 100644 index 0000000000..a0325cc183 --- /dev/null +++ b/src/core/tsi/ssl_transport_security.c @@ -0,0 +1,1572 @@ +/* + * + * Copyright 2015, Google Inc. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * * Neither the name of Google Inc. nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + */ + +#include "src/core/tsi/ssl_transport_security.h" + +#include <grpc/support/port_platform.h> + +#include <limits.h> +#include <string.h> + +/* TODO(jboeuf): refactor inet_ntop into a portability header. */ +/* Note: for whomever reads this and tries to refactor this, this + can't be in grpc, it has to be in gpr. */ +#ifdef GPR_WINDOWS +#include <ws2tcpip.h> +#else +#include <arpa/inet.h> +#endif + +#include <grpc/support/alloc.h> +#include <grpc/support/log.h> +#include <grpc/support/sync.h> +#include <grpc/support/thd.h> +#include <grpc/support/useful.h> + +#include <openssl/bio.h> +#include <openssl/crypto.h> /* For OPENSSL_free */ +#include <openssl/err.h> +#include <openssl/ssl.h> +#include <openssl/x509.h> +#include <openssl/x509v3.h> + +#include "src/core/tsi/ssl_types.h" +#include "src/core/tsi/transport_security.h" + +/* --- Constants. ---*/ + +#define TSI_SSL_MAX_PROTECTED_FRAME_SIZE_UPPER_BOUND 16384 +#define TSI_SSL_MAX_PROTECTED_FRAME_SIZE_LOWER_BOUND 1024 + +/* Putting a macro like this and littering the source file with #if is really + bad practice. + TODO(jboeuf): refactor all the #if / #endif in a separate module. */ +#ifndef TSI_OPENSSL_ALPN_SUPPORT +#define TSI_OPENSSL_ALPN_SUPPORT 1 +#endif + +/* TODO(jboeuf): I have not found a way to get this number dynamically from the + SSL structure. This is what we would ultimately want though... */ +#define TSI_SSL_MAX_PROTECTION_OVERHEAD 100 + +/* --- Structure definitions. ---*/ + +struct tsi_ssl_handshaker_factory { + tsi_result (*create_handshaker)(tsi_ssl_handshaker_factory *self, + const char *server_name_indication, + tsi_handshaker **handshaker); + void (*destroy)(tsi_ssl_handshaker_factory *self); +}; + +typedef struct { + tsi_ssl_handshaker_factory base; + SSL_CTX *ssl_context; + unsigned char *alpn_protocol_list; + size_t alpn_protocol_list_length; +} tsi_ssl_client_handshaker_factory; + +typedef struct { + tsi_ssl_handshaker_factory base; + + /* Several contexts to support SNI. + The tsi_peer array contains the subject names of the server certificates + associated with the contexts at the same index. */ + SSL_CTX **ssl_contexts; + tsi_peer *ssl_context_x509_subject_names; + size_t ssl_context_count; + unsigned char *alpn_protocol_list; + size_t alpn_protocol_list_length; +} tsi_ssl_server_handshaker_factory; + +typedef struct { + tsi_handshaker base; + SSL *ssl; + BIO *into_ssl; + BIO *from_ssl; + tsi_result result; +} tsi_ssl_handshaker; + +typedef struct { + tsi_frame_protector base; + SSL *ssl; + BIO *into_ssl; + BIO *from_ssl; + unsigned char *buffer; + size_t buffer_size; + size_t buffer_offset; +} tsi_ssl_frame_protector; + +/* --- Library Initialization. ---*/ + +static gpr_once init_openssl_once = GPR_ONCE_INIT; +static gpr_mu *openssl_mutexes = NULL; + +static void openssl_locking_cb(int mode, int type, const char *file, int line) { + if (mode & CRYPTO_LOCK) { + gpr_mu_lock(&openssl_mutexes[type]); + } else { + gpr_mu_unlock(&openssl_mutexes[type]); + } +} + +static unsigned long openssl_thread_id_cb(void) { + return (unsigned long)gpr_thd_currentid(); +} + +static void init_openssl(void) { + int i; + int num_locks; + SSL_library_init(); + SSL_load_error_strings(); + OpenSSL_add_all_algorithms(); + num_locks = CRYPTO_num_locks(); + GPR_ASSERT(num_locks > 0); + openssl_mutexes = gpr_malloc((size_t)num_locks * sizeof(gpr_mu)); + for (i = 0; i < CRYPTO_num_locks(); i++) { + gpr_mu_init(&openssl_mutexes[i]); + } + CRYPTO_set_locking_callback(openssl_locking_cb); + CRYPTO_set_id_callback(openssl_thread_id_cb); +} + +/* --- Ssl utils. ---*/ + +static const char *ssl_error_string(int error) { + switch (error) { + case SSL_ERROR_NONE: + return "SSL_ERROR_NONE"; + case SSL_ERROR_ZERO_RETURN: + return "SSL_ERROR_ZERO_RETURN"; + case SSL_ERROR_WANT_READ: + return "SSL_ERROR_WANT_READ"; + case SSL_ERROR_WANT_WRITE: + return "SSL_ERROR_WANT_WRITE"; + case SSL_ERROR_WANT_CONNECT: + return "SSL_ERROR_WANT_CONNECT"; + case SSL_ERROR_WANT_ACCEPT: + return "SSL_ERROR_WANT_ACCEPT"; + case SSL_ERROR_WANT_X509_LOOKUP: + return "SSL_ERROR_WANT_X509_LOOKUP"; + case SSL_ERROR_SYSCALL: + return "SSL_ERROR_SYSCALL"; + case SSL_ERROR_SSL: + return "SSL_ERROR_SSL"; + default: + return "Unknown error"; + } +} + +/* TODO(jboeuf): Remove when we are past the debugging phase with this code. */ +static void ssl_log_where_info(const SSL *ssl, int where, int flag, + const char *msg) { + if ((where & flag) && tsi_tracing_enabled) { + gpr_log(GPR_INFO, "%20.20s - %30.30s - %5.10s", msg, + SSL_state_string_long(ssl), SSL_state_string(ssl)); + } +} + +/* Used for debugging. TODO(jboeuf): Remove when code is mature enough. */ +static void ssl_info_callback(const SSL *ssl, int where, int ret) { + if (ret == 0) { + gpr_log(GPR_ERROR, "ssl_info_callback: error occured.\n"); + return; + } + + ssl_log_where_info(ssl, where, SSL_CB_LOOP, "LOOP"); + ssl_log_where_info(ssl, where, SSL_CB_HANDSHAKE_START, "HANDSHAKE START"); + ssl_log_where_info(ssl, where, SSL_CB_HANDSHAKE_DONE, "HANDSHAKE DONE"); +} + +/* Returns 1 if name looks like an IP address, 0 otherwise. + This is a very rough heuristic, and only handles IPv6 in hexadecimal form. */ +static int looks_like_ip_address(const char *name) { + size_t i; + size_t dot_count = 0; + size_t num_size = 0; + for (i = 0; i < strlen(name); i++) { + if (name[i] == ':') { + /* IPv6 Address in hexadecimal form, : is not allowed in DNS names. */ + return 1; + } + if (name[i] >= '0' && name[i] <= '9') { + if (num_size > 3) return 0; + num_size++; + } else if (name[i] == '.') { + if (dot_count > 3 || num_size == 0) return 0; + dot_count++; + num_size = 0; + } else { + return 0; + } + } + if (dot_count < 3 || num_size == 0) return 0; + return 1; +} + +/* Gets the subject CN from an X509 cert. */ +static tsi_result ssl_get_x509_common_name(X509 *cert, unsigned char **utf8, + size_t *utf8_size) { + int common_name_index = -1; + X509_NAME_ENTRY *common_name_entry = NULL; + ASN1_STRING *common_name_asn1 = NULL; + X509_NAME *subject_name = X509_get_subject_name(cert); + int utf8_returned_size = 0; + if (subject_name == NULL) { + gpr_log(GPR_ERROR, "Could not get subject name from certificate."); + return TSI_NOT_FOUND; + } + common_name_index = + X509_NAME_get_index_by_NID(subject_name, NID_commonName, -1); + if (common_name_index == -1) { + gpr_log(GPR_ERROR, + "Could not get common name of subject from certificate."); + return TSI_NOT_FOUND; + } + common_name_entry = X509_NAME_get_entry(subject_name, common_name_index); + if (common_name_entry == NULL) { + gpr_log(GPR_ERROR, "Could not get common name entry from certificate."); + return TSI_INTERNAL_ERROR; + } + common_name_asn1 = X509_NAME_ENTRY_get_data(common_name_entry); + if (common_name_asn1 == NULL) { + gpr_log(GPR_ERROR, + "Could not get common name entry asn1 from certificate."); + return TSI_INTERNAL_ERROR; + } + utf8_returned_size = ASN1_STRING_to_UTF8(utf8, common_name_asn1); + if (utf8_returned_size < 0) { + gpr_log(GPR_ERROR, "Could not extract utf8 from asn1 string."); + return TSI_OUT_OF_RESOURCES; + } + *utf8_size = (size_t)utf8_returned_size; + return TSI_OK; +} + +/* Gets the subject CN of an X509 cert as a tsi_peer_property. */ +static tsi_result peer_property_from_x509_common_name( + X509 *cert, tsi_peer_property *property) { + unsigned char *common_name; + size_t common_name_size; + tsi_result result = + ssl_get_x509_common_name(cert, &common_name, &common_name_size); + if (result != TSI_OK) { + if (result == TSI_NOT_FOUND) { + common_name = NULL; + common_name_size = 0; + } else { + return result; + } + } + result = tsi_construct_string_peer_property( + TSI_X509_SUBJECT_COMMON_NAME_PEER_PROPERTY, + common_name == NULL ? "" : (const char *)common_name, common_name_size, + property); + OPENSSL_free(common_name); + return result; +} + +/* Gets the X509 cert in PEM format as a tsi_peer_property. */ +static tsi_result add_pem_certificate(X509 *cert, tsi_peer_property *property) { + BIO *bio = BIO_new(BIO_s_mem()); + if (!PEM_write_bio_X509(bio, cert)) { + BIO_free(bio); + return TSI_INTERNAL_ERROR; + } + char *contents; + long len = BIO_get_mem_data(bio, &contents); + if (len <= 0) { + BIO_free(bio); + return TSI_INTERNAL_ERROR; + } + tsi_result result = tsi_construct_string_peer_property( + TSI_X509_PEM_CERT_PROPERTY, (const char *)contents, (size_t)len, + property); + BIO_free(bio); + return result; +} + +/* Gets the subject SANs from an X509 cert as a tsi_peer_property. */ +static tsi_result add_subject_alt_names_properties_to_peer( + tsi_peer *peer, GENERAL_NAMES *subject_alt_names, + size_t subject_alt_name_count) { + size_t i; + tsi_result result = TSI_OK; + + /* Reset for DNS entries filtering. */ + peer->property_count -= subject_alt_name_count; + + for (i = 0; i < subject_alt_name_count; i++) { + GENERAL_NAME *subject_alt_name = + sk_GENERAL_NAME_value(subject_alt_names, TSI_SIZE_AS_SIZE(i)); + /* Filter out the non-dns entries names. */ + if (subject_alt_name->type == GEN_DNS) { + unsigned char *name = NULL; + int name_size; + name_size = ASN1_STRING_to_UTF8(&name, subject_alt_name->d.dNSName); + if (name_size < 0) { + gpr_log(GPR_ERROR, "Could not get utf8 from asn1 string."); + result = TSI_INTERNAL_ERROR; + break; + } + result = tsi_construct_string_peer_property( + TSI_X509_SUBJECT_ALTERNATIVE_NAME_PEER_PROPERTY, (const char *)name, + (size_t)name_size, &peer->properties[peer->property_count++]); + OPENSSL_free(name); + } else if (subject_alt_name->type == GEN_IPADD) { + char ntop_buf[INET6_ADDRSTRLEN]; + int af; + + if (subject_alt_name->d.iPAddress->length == 4) { + af = AF_INET; + } else if (subject_alt_name->d.iPAddress->length == 16) { + af = AF_INET6; + } else { + gpr_log(GPR_ERROR, "SAN IP Address contained invalid IP"); + result = TSI_INTERNAL_ERROR; + break; + } + const char *name = inet_ntop(af, subject_alt_name->d.iPAddress->data, + ntop_buf, INET6_ADDRSTRLEN); + if (name == NULL) { + gpr_log(GPR_ERROR, "Could not get IP string from asn1 octet."); + result = TSI_INTERNAL_ERROR; + break; + } + + result = tsi_construct_string_peer_property_from_cstring( + TSI_X509_SUBJECT_ALTERNATIVE_NAME_PEER_PROPERTY, name, + &peer->properties[peer->property_count++]); + } + if (result != TSI_OK) break; + } + return result; +} + +/* Gets information about the peer's X509 cert as a tsi_peer object. */ +static tsi_result peer_from_x509(X509 *cert, int include_certificate_type, + tsi_peer *peer) { + /* TODO(jboeuf): Maybe add more properties. */ + GENERAL_NAMES *subject_alt_names = + X509_get_ext_d2i(cert, NID_subject_alt_name, 0, 0); + int subject_alt_name_count = (subject_alt_names != NULL) + ? (int)sk_GENERAL_NAME_num(subject_alt_names) + : 0; + size_t property_count; + tsi_result result; + GPR_ASSERT(subject_alt_name_count >= 0); + property_count = (include_certificate_type ? (size_t)1 : 0) + + 2 /* common name, certificate */ + + (size_t)subject_alt_name_count; + result = tsi_construct_peer(property_count, peer); + if (result != TSI_OK) return result; + do { + if (include_certificate_type) { + result = tsi_construct_string_peer_property_from_cstring( + TSI_CERTIFICATE_TYPE_PEER_PROPERTY, TSI_X509_CERTIFICATE_TYPE, + &peer->properties[0]); + if (result != TSI_OK) break; + } + result = peer_property_from_x509_common_name( + cert, &peer->properties[include_certificate_type ? 1 : 0]); + if (result != TSI_OK) break; + + result = add_pem_certificate( + cert, &peer->properties[include_certificate_type ? 2 : 1]); + if (result != TSI_OK) break; + + if (subject_alt_name_count != 0) { + result = add_subject_alt_names_properties_to_peer( + peer, subject_alt_names, (size_t)subject_alt_name_count); + if (result != TSI_OK) break; + } + } while (0); + + if (subject_alt_names != NULL) { + sk_GENERAL_NAME_pop_free(subject_alt_names, GENERAL_NAME_free); + } + if (result != TSI_OK) tsi_peer_destruct(peer); + return result; +} + +/* Logs the SSL error stack. */ +static void log_ssl_error_stack(void) { + unsigned long err; + while ((err = ERR_get_error()) != 0) { + char details[256]; + ERR_error_string_n((uint32_t)err, details, sizeof(details)); + gpr_log(GPR_ERROR, "%s", details); + } +} + +/* Performs an SSL_read and handle errors. */ +static tsi_result do_ssl_read(SSL *ssl, unsigned char *unprotected_bytes, + size_t *unprotected_bytes_size) { + int read_from_ssl; + GPR_ASSERT(*unprotected_bytes_size <= INT_MAX); + read_from_ssl = + SSL_read(ssl, unprotected_bytes, (int)*unprotected_bytes_size); + if (read_from_ssl == 0) { + gpr_log(GPR_ERROR, "SSL_read returned 0 unexpectedly."); + return TSI_INTERNAL_ERROR; + } + if (read_from_ssl < 0) { + read_from_ssl = SSL_get_error(ssl, read_from_ssl); + switch (read_from_ssl) { + case SSL_ERROR_WANT_READ: + /* We need more data to finish the frame. */ + *unprotected_bytes_size = 0; + return TSI_OK; + case SSL_ERROR_WANT_WRITE: + gpr_log( + GPR_ERROR, + "Peer tried to renegotiate SSL connection. This is unsupported."); + return TSI_UNIMPLEMENTED; + case SSL_ERROR_SSL: + gpr_log(GPR_ERROR, "Corruption detected."); + log_ssl_error_stack(); + return TSI_DATA_CORRUPTED; + default: + gpr_log(GPR_ERROR, "SSL_read failed with error %s.", + ssl_error_string(read_from_ssl)); + return TSI_PROTOCOL_FAILURE; + } + } + *unprotected_bytes_size = (size_t)read_from_ssl; + return TSI_OK; +} + +/* Performs an SSL_write and handle errors. */ +static tsi_result do_ssl_write(SSL *ssl, unsigned char *unprotected_bytes, + size_t unprotected_bytes_size) { + int ssl_write_result; + GPR_ASSERT(unprotected_bytes_size <= INT_MAX); + ssl_write_result = + SSL_write(ssl, unprotected_bytes, (int)unprotected_bytes_size); + if (ssl_write_result < 0) { + ssl_write_result = SSL_get_error(ssl, ssl_write_result); + if (ssl_write_result == SSL_ERROR_WANT_READ) { + gpr_log(GPR_ERROR, + "Peer tried to renegotiate SSL connection. This is unsupported."); + return TSI_UNIMPLEMENTED; + } else { + gpr_log(GPR_ERROR, "SSL_write failed with error %s.", + ssl_error_string(ssl_write_result)); + return TSI_INTERNAL_ERROR; + } + } + return TSI_OK; +} + +/* Loads an in-memory PEM certificate chain into the SSL context. */ +static tsi_result ssl_ctx_use_certificate_chain( + SSL_CTX *context, const unsigned char *pem_cert_chain, + size_t pem_cert_chain_size) { + tsi_result result = TSI_OK; + X509 *certificate = NULL; + BIO *pem; + GPR_ASSERT(pem_cert_chain_size <= INT_MAX); + pem = BIO_new_mem_buf((void *)pem_cert_chain, (int)pem_cert_chain_size); + if (pem == NULL) return TSI_OUT_OF_RESOURCES; + + do { + certificate = PEM_read_bio_X509_AUX(pem, NULL, NULL, ""); + if (certificate == NULL) { + result = TSI_INVALID_ARGUMENT; + break; + } + if (!SSL_CTX_use_certificate(context, certificate)) { + result = TSI_INVALID_ARGUMENT; + break; + } + while (1) { + X509 *certificate_authority = PEM_read_bio_X509(pem, NULL, NULL, ""); + if (certificate_authority == NULL) { + ERR_clear_error(); + break; /* Done reading. */ + } + if (!SSL_CTX_add_extra_chain_cert(context, certificate_authority)) { + X509_free(certificate_authority); + result = TSI_INVALID_ARGUMENT; + break; + } + /* We don't need to free certificate_authority as its ownership has been + transfered to the context. That is not the case for certificate though. + */ + } + } while (0); + + if (certificate != NULL) X509_free(certificate); + BIO_free(pem); + return result; +} + +/* Loads an in-memory PEM private key into the SSL context. */ +static tsi_result ssl_ctx_use_private_key(SSL_CTX *context, + const unsigned char *pem_key, + size_t pem_key_size) { + tsi_result result = TSI_OK; + EVP_PKEY *private_key = NULL; + BIO *pem; + GPR_ASSERT(pem_key_size <= INT_MAX); + pem = BIO_new_mem_buf((void *)pem_key, (int)pem_key_size); + if (pem == NULL) return TSI_OUT_OF_RESOURCES; + do { + private_key = PEM_read_bio_PrivateKey(pem, NULL, NULL, ""); + if (private_key == NULL) { + result = TSI_INVALID_ARGUMENT; + break; + } + if (!SSL_CTX_use_PrivateKey(context, private_key)) { + result = TSI_INVALID_ARGUMENT; + break; + } + } while (0); + if (private_key != NULL) EVP_PKEY_free(private_key); + BIO_free(pem); + return result; +} + +/* Loads in-memory PEM verification certs into the SSL context and optionally + returns the verification cert names (root_names can be NULL). */ +static tsi_result ssl_ctx_load_verification_certs( + SSL_CTX *context, const unsigned char *pem_roots, size_t pem_roots_size, + STACK_OF(X509_NAME) * *root_names) { + tsi_result result = TSI_OK; + size_t num_roots = 0; + X509 *root = NULL; + X509_NAME *root_name = NULL; + BIO *pem; + X509_STORE *root_store; + GPR_ASSERT(pem_roots_size <= INT_MAX); + pem = BIO_new_mem_buf((void *)pem_roots, (int)pem_roots_size); + root_store = SSL_CTX_get_cert_store(context); + if (root_store == NULL) return TSI_INVALID_ARGUMENT; + if (pem == NULL) return TSI_OUT_OF_RESOURCES; + if (root_names != NULL) { + *root_names = sk_X509_NAME_new_null(); + if (*root_names == NULL) return TSI_OUT_OF_RESOURCES; + } + + while (1) { + root = PEM_read_bio_X509_AUX(pem, NULL, NULL, ""); + if (root == NULL) { + ERR_clear_error(); + break; /* We're at the end of stream. */ + } + if (root_names != NULL) { + root_name = X509_get_subject_name(root); + if (root_name == NULL) { + gpr_log(GPR_ERROR, "Could not get name from root certificate."); + result = TSI_INVALID_ARGUMENT; + break; + } + root_name = X509_NAME_dup(root_name); + if (root_name == NULL) { + result = TSI_OUT_OF_RESOURCES; + break; + } + sk_X509_NAME_push(*root_names, root_name); + root_name = NULL; + } + if (!X509_STORE_add_cert(root_store, root)) { + gpr_log(GPR_ERROR, "Could not add root certificate to ssl context."); + result = TSI_INTERNAL_ERROR; + break; + } + X509_free(root); + num_roots++; + } + + if (num_roots == 0) { + gpr_log(GPR_ERROR, "Could not load any root certificate."); + result = TSI_INVALID_ARGUMENT; + } + + if (result != TSI_OK) { + if (root != NULL) X509_free(root); + if (root_names != NULL) { + sk_X509_NAME_pop_free(*root_names, X509_NAME_free); + *root_names = NULL; + if (root_name != NULL) X509_NAME_free(root_name); + } + } + BIO_free(pem); + return result; +} + +/* Populates the SSL context with a private key and a cert chain, and sets the + cipher list and the ephemeral ECDH key. */ +static tsi_result populate_ssl_context( + SSL_CTX *context, const unsigned char *pem_private_key, + size_t pem_private_key_size, const unsigned char *pem_certificate_chain, + size_t pem_certificate_chain_size, const char *cipher_list) { + tsi_result result = TSI_OK; + if (pem_certificate_chain != NULL) { + result = ssl_ctx_use_certificate_chain(context, pem_certificate_chain, + pem_certificate_chain_size); + if (result != TSI_OK) { + gpr_log(GPR_ERROR, "Invalid cert chain file."); + return result; + } + } + if (pem_private_key != NULL) { + result = + ssl_ctx_use_private_key(context, pem_private_key, pem_private_key_size); + if (result != TSI_OK || !SSL_CTX_check_private_key(context)) { + gpr_log(GPR_ERROR, "Invalid private key."); + return result != TSI_OK ? result : TSI_INVALID_ARGUMENT; + } + } + if ((cipher_list != NULL) && !SSL_CTX_set_cipher_list(context, cipher_list)) { + gpr_log(GPR_ERROR, "Invalid cipher list: %s.", cipher_list); + return TSI_INVALID_ARGUMENT; + } + { + EC_KEY *ecdh = EC_KEY_new_by_curve_name(NID_X9_62_prime256v1); + if (!SSL_CTX_set_tmp_ecdh(context, ecdh)) { + gpr_log(GPR_ERROR, "Could not set ephemeral ECDH key."); + EC_KEY_free(ecdh); + return TSI_INTERNAL_ERROR; + } + SSL_CTX_set_options(context, SSL_OP_SINGLE_ECDH_USE); + EC_KEY_free(ecdh); + } + return TSI_OK; +} + +/* Extracts the CN and the SANs from an X509 cert as a peer object. */ +static tsi_result extract_x509_subject_names_from_pem_cert( + const unsigned char *pem_cert, size_t pem_cert_size, tsi_peer *peer) { + tsi_result result = TSI_OK; + X509 *cert = NULL; + BIO *pem; + GPR_ASSERT(pem_cert_size <= INT_MAX); + pem = BIO_new_mem_buf((void *)pem_cert, (int)pem_cert_size); + if (pem == NULL) return TSI_OUT_OF_RESOURCES; + + cert = PEM_read_bio_X509(pem, NULL, NULL, ""); + if (cert == NULL) { + gpr_log(GPR_ERROR, "Invalid certificate"); + result = TSI_INVALID_ARGUMENT; + } else { + result = peer_from_x509(cert, 0, peer); + } + if (cert != NULL) X509_free(cert); + BIO_free(pem); + return result; +} + +/* Builds the alpn protocol name list according to rfc 7301. */ +static tsi_result build_alpn_protocol_name_list( + const unsigned char **alpn_protocols, + const unsigned char *alpn_protocols_lengths, uint16_t num_alpn_protocols, + unsigned char **protocol_name_list, size_t *protocol_name_list_length) { + uint16_t i; + unsigned char *current; + *protocol_name_list = NULL; + *protocol_name_list_length = 0; + if (num_alpn_protocols == 0) return TSI_INVALID_ARGUMENT; + for (i = 0; i < num_alpn_protocols; i++) { + if (alpn_protocols_lengths[i] == 0) { + gpr_log(GPR_ERROR, "Invalid 0-length protocol name."); + return TSI_INVALID_ARGUMENT; + } + *protocol_name_list_length += (size_t)alpn_protocols_lengths[i] + 1; + } + *protocol_name_list = gpr_malloc(*protocol_name_list_length); + if (*protocol_name_list == NULL) return TSI_OUT_OF_RESOURCES; + current = *protocol_name_list; + for (i = 0; i < num_alpn_protocols; i++) { + *(current++) = alpn_protocols_lengths[i]; + memcpy(current, alpn_protocols[i], alpn_protocols_lengths[i]); + current += alpn_protocols_lengths[i]; + } + /* Safety check. */ + if ((current < *protocol_name_list) || + ((uintptr_t)(current - *protocol_name_list) != + *protocol_name_list_length)) { + return TSI_INTERNAL_ERROR; + } + return TSI_OK; +} + +// The verification callback is used for clients that don't really care about +// the server's certificate, but we need to pull it anyway, in case a higher +// layer wants to look at it. In this case the verification may fail, but +// we don't really care. +static int NullVerifyCallback(int preverify_ok, X509_STORE_CTX *ctx) { + return 1; +} + +/* --- tsi_frame_protector methods implementation. ---*/ + +static tsi_result ssl_protector_protect(tsi_frame_protector *self, + const unsigned char *unprotected_bytes, + size_t *unprotected_bytes_size, + unsigned char *protected_output_frames, + size_t *protected_output_frames_size) { + tsi_ssl_frame_protector *impl = (tsi_ssl_frame_protector *)self; + int read_from_ssl; + size_t available; + tsi_result result = TSI_OK; + + /* First see if we have some pending data in the SSL BIO. */ + int pending_in_ssl = (int)BIO_pending(impl->from_ssl); + if (pending_in_ssl > 0) { + *unprotected_bytes_size = 0; + GPR_ASSERT(*protected_output_frames_size <= INT_MAX); + read_from_ssl = BIO_read(impl->from_ssl, protected_output_frames, + (int)*protected_output_frames_size); + if (read_from_ssl < 0) { + gpr_log(GPR_ERROR, + "Could not read from BIO even though some data is pending"); + return TSI_INTERNAL_ERROR; + } + *protected_output_frames_size = (size_t)read_from_ssl; + return TSI_OK; + } + + /* Now see if we can send a complete frame. */ + available = impl->buffer_size - impl->buffer_offset; + if (available > *unprotected_bytes_size) { + /* If we cannot, just copy the data in our internal buffer. */ + memcpy(impl->buffer + impl->buffer_offset, unprotected_bytes, + *unprotected_bytes_size); + impl->buffer_offset += *unprotected_bytes_size; + *protected_output_frames_size = 0; + return TSI_OK; + } + + /* If we can, prepare the buffer, send it to SSL_write and read. */ + memcpy(impl->buffer + impl->buffer_offset, unprotected_bytes, available); + result = do_ssl_write(impl->ssl, impl->buffer, impl->buffer_size); + if (result != TSI_OK) return result; + + GPR_ASSERT(*protected_output_frames_size <= INT_MAX); + read_from_ssl = BIO_read(impl->from_ssl, protected_output_frames, + (int)*protected_output_frames_size); + if (read_from_ssl < 0) { + gpr_log(GPR_ERROR, "Could not read from BIO after SSL_write."); + return TSI_INTERNAL_ERROR; + } + *protected_output_frames_size = (size_t)read_from_ssl; + *unprotected_bytes_size = available; + impl->buffer_offset = 0; + return TSI_OK; +} + +static tsi_result ssl_protector_protect_flush( + tsi_frame_protector *self, unsigned char *protected_output_frames, + size_t *protected_output_frames_size, size_t *still_pending_size) { + tsi_result result = TSI_OK; + tsi_ssl_frame_protector *impl = (tsi_ssl_frame_protector *)self; + int read_from_ssl = 0; + int pending; + + if (impl->buffer_offset != 0) { + result = do_ssl_write(impl->ssl, impl->buffer, impl->buffer_offset); + if (result != TSI_OK) return result; + impl->buffer_offset = 0; + } + + pending = (int)BIO_pending(impl->from_ssl); + GPR_ASSERT(pending >= 0); + *still_pending_size = (size_t)pending; + if (*still_pending_size == 0) return TSI_OK; + + GPR_ASSERT(*protected_output_frames_size <= INT_MAX); + read_from_ssl = BIO_read(impl->from_ssl, protected_output_frames, + (int)*protected_output_frames_size); + if (read_from_ssl <= 0) { + gpr_log(GPR_ERROR, "Could not read from BIO after SSL_write."); + return TSI_INTERNAL_ERROR; + } + *protected_output_frames_size = (size_t)read_from_ssl; + pending = (int)BIO_pending(impl->from_ssl); + GPR_ASSERT(pending >= 0); + *still_pending_size = (size_t)pending; + return TSI_OK; +} + +static tsi_result ssl_protector_unprotect( + tsi_frame_protector *self, const unsigned char *protected_frames_bytes, + size_t *protected_frames_bytes_size, unsigned char *unprotected_bytes, + size_t *unprotected_bytes_size) { + tsi_result result = TSI_OK; + int written_into_ssl = 0; + size_t output_bytes_size = *unprotected_bytes_size; + size_t output_bytes_offset = 0; + tsi_ssl_frame_protector *impl = (tsi_ssl_frame_protector *)self; + + /* First, try to read remaining data from ssl. */ + result = do_ssl_read(impl->ssl, unprotected_bytes, unprotected_bytes_size); + if (result != TSI_OK) return result; + if (*unprotected_bytes_size == output_bytes_size) { + /* We have read everything we could and cannot process any more input. */ + *protected_frames_bytes_size = 0; + return TSI_OK; + } + output_bytes_offset = *unprotected_bytes_size; + unprotected_bytes += output_bytes_offset; + *unprotected_bytes_size = output_bytes_size - output_bytes_offset; + + /* Then, try to write some data to ssl. */ + GPR_ASSERT(*protected_frames_bytes_size <= INT_MAX); + written_into_ssl = BIO_write(impl->into_ssl, protected_frames_bytes, + (int)*protected_frames_bytes_size); + if (written_into_ssl < 0) { + gpr_log(GPR_ERROR, "Sending protected frame to ssl failed with %d", + written_into_ssl); + return TSI_INTERNAL_ERROR; + } + *protected_frames_bytes_size = (size_t)written_into_ssl; + + /* Now try to read some data again. */ + result = do_ssl_read(impl->ssl, unprotected_bytes, unprotected_bytes_size); + if (result == TSI_OK) { + /* Don't forget to output the total number of bytes read. */ + *unprotected_bytes_size += output_bytes_offset; + } + return result; +} + +static void ssl_protector_destroy(tsi_frame_protector *self) { + tsi_ssl_frame_protector *impl = (tsi_ssl_frame_protector *)self; + if (impl->buffer != NULL) gpr_free(impl->buffer); + if (impl->ssl != NULL) SSL_free(impl->ssl); + gpr_free(self); +} + +static const tsi_frame_protector_vtable frame_protector_vtable = { + ssl_protector_protect, ssl_protector_protect_flush, ssl_protector_unprotect, + ssl_protector_destroy, +}; + +/* --- tsi_handshaker methods implementation. ---*/ + +static tsi_result ssl_handshaker_get_bytes_to_send_to_peer(tsi_handshaker *self, + unsigned char *bytes, + size_t *bytes_size) { + tsi_ssl_handshaker *impl = (tsi_ssl_handshaker *)self; + int bytes_read_from_ssl = 0; + if (bytes == NULL || bytes_size == NULL || *bytes_size == 0 || + *bytes_size > INT_MAX) { + return TSI_INVALID_ARGUMENT; + } + GPR_ASSERT(*bytes_size <= INT_MAX); + bytes_read_from_ssl = BIO_read(impl->from_ssl, bytes, (int)*bytes_size); + if (bytes_read_from_ssl < 0) { + *bytes_size = 0; + if (!BIO_should_retry(impl->from_ssl)) { + impl->result = TSI_INTERNAL_ERROR; + return impl->result; + } else { + return TSI_OK; + } + } + *bytes_size = (size_t)bytes_read_from_ssl; + return BIO_pending(impl->from_ssl) == 0 ? TSI_OK : TSI_INCOMPLETE_DATA; +} + +static tsi_result ssl_handshaker_get_result(tsi_handshaker *self) { + tsi_ssl_handshaker *impl = (tsi_ssl_handshaker *)self; + if ((impl->result == TSI_HANDSHAKE_IN_PROGRESS) && + SSL_is_init_finished(impl->ssl)) { + impl->result = TSI_OK; + } + return impl->result; +} + +static tsi_result ssl_handshaker_process_bytes_from_peer( + tsi_handshaker *self, const unsigned char *bytes, size_t *bytes_size) { + tsi_ssl_handshaker *impl = (tsi_ssl_handshaker *)self; + int bytes_written_into_ssl_size = 0; + if (bytes == NULL || bytes_size == 0 || *bytes_size > INT_MAX) { + return TSI_INVALID_ARGUMENT; + } + GPR_ASSERT(*bytes_size <= INT_MAX); + bytes_written_into_ssl_size = + BIO_write(impl->into_ssl, bytes, (int)*bytes_size); + if (bytes_written_into_ssl_size < 0) { + gpr_log(GPR_ERROR, "Could not write to memory BIO."); + impl->result = TSI_INTERNAL_ERROR; + return impl->result; + } + *bytes_size = (size_t)bytes_written_into_ssl_size; + + if (!tsi_handshaker_is_in_progress(self)) { + impl->result = TSI_OK; + return impl->result; + } else { + /* Get ready to get some bytes from SSL. */ + int ssl_result = SSL_do_handshake(impl->ssl); + ssl_result = SSL_get_error(impl->ssl, ssl_result); + switch (ssl_result) { + case SSL_ERROR_WANT_READ: + if (BIO_pending(impl->from_ssl) == 0) { + /* We need more data. */ + return TSI_INCOMPLETE_DATA; + } else { + return TSI_OK; + } + case SSL_ERROR_NONE: + return TSI_OK; + default: { + char err_str[256]; + ERR_error_string_n(ERR_get_error(), err_str, sizeof(err_str)); + gpr_log(GPR_ERROR, "Handshake failed with fatal error %s: %s.", + ssl_error_string(ssl_result), err_str); + impl->result = TSI_PROTOCOL_FAILURE; + return impl->result; + } + } + } +} + +static tsi_result ssl_handshaker_extract_peer(tsi_handshaker *self, + tsi_peer *peer) { + tsi_result result = TSI_OK; + const unsigned char *alpn_selected = NULL; + unsigned int alpn_selected_len; + tsi_ssl_handshaker *impl = (tsi_ssl_handshaker *)self; + X509 *peer_cert = SSL_get_peer_certificate(impl->ssl); + if (peer_cert != NULL) { + result = peer_from_x509(peer_cert, 1, peer); + X509_free(peer_cert); + if (result != TSI_OK) return result; + } +#if TSI_OPENSSL_ALPN_SUPPORT + SSL_get0_alpn_selected(impl->ssl, &alpn_selected, &alpn_selected_len); +#endif /* TSI_OPENSSL_ALPN_SUPPORT */ + if (alpn_selected == NULL) { + /* Try npn. */ + SSL_get0_next_proto_negotiated(impl->ssl, &alpn_selected, + &alpn_selected_len); + } + if (alpn_selected != NULL) { + size_t i; + tsi_peer_property *new_properties = + gpr_zalloc(sizeof(*new_properties) * (peer->property_count + 1)); + for (i = 0; i < peer->property_count; i++) { + new_properties[i] = peer->properties[i]; + } + result = tsi_construct_string_peer_property( + TSI_SSL_ALPN_SELECTED_PROTOCOL, (const char *)alpn_selected, + alpn_selected_len, &new_properties[peer->property_count]); + if (result != TSI_OK) { + gpr_free(new_properties); + return result; + } + if (peer->properties != NULL) gpr_free(peer->properties); + peer->property_count++; + peer->properties = new_properties; + } + return result; +} + +static tsi_result ssl_handshaker_create_frame_protector( + tsi_handshaker *self, size_t *max_output_protected_frame_size, + tsi_frame_protector **protector) { + size_t actual_max_output_protected_frame_size = + TSI_SSL_MAX_PROTECTED_FRAME_SIZE_UPPER_BOUND; + tsi_ssl_handshaker *impl = (tsi_ssl_handshaker *)self; + tsi_ssl_frame_protector *protector_impl = gpr_zalloc(sizeof(*protector_impl)); + + if (max_output_protected_frame_size != NULL) { + if (*max_output_protected_frame_size > + TSI_SSL_MAX_PROTECTED_FRAME_SIZE_UPPER_BOUND) { + *max_output_protected_frame_size = + TSI_SSL_MAX_PROTECTED_FRAME_SIZE_UPPER_BOUND; + } else if (*max_output_protected_frame_size < + TSI_SSL_MAX_PROTECTED_FRAME_SIZE_LOWER_BOUND) { + *max_output_protected_frame_size = + TSI_SSL_MAX_PROTECTED_FRAME_SIZE_LOWER_BOUND; + } + actual_max_output_protected_frame_size = *max_output_protected_frame_size; + } + protector_impl->buffer_size = + actual_max_output_protected_frame_size - TSI_SSL_MAX_PROTECTION_OVERHEAD; + protector_impl->buffer = gpr_malloc(protector_impl->buffer_size); + if (protector_impl->buffer == NULL) { + gpr_log(GPR_ERROR, + "Could not allocated buffer for tsi_ssl_frame_protector."); + gpr_free(protector_impl); + return TSI_INTERNAL_ERROR; + } + + /* Transfer ownership of ssl to the frame protector. It is OK as the caller + * cannot call anything else but destroy on the handshaker after this call. */ + protector_impl->ssl = impl->ssl; + impl->ssl = NULL; + protector_impl->into_ssl = impl->into_ssl; + protector_impl->from_ssl = impl->from_ssl; + + protector_impl->base.vtable = &frame_protector_vtable; + *protector = &protector_impl->base; + return TSI_OK; +} + +static void ssl_handshaker_destroy(tsi_handshaker *self) { + tsi_ssl_handshaker *impl = (tsi_ssl_handshaker *)self; + SSL_free(impl->ssl); /* The BIO objects are owned by ssl */ + gpr_free(impl); +} + +static const tsi_handshaker_vtable handshaker_vtable = { + ssl_handshaker_get_bytes_to_send_to_peer, + ssl_handshaker_process_bytes_from_peer, + ssl_handshaker_get_result, + ssl_handshaker_extract_peer, + ssl_handshaker_create_frame_protector, + ssl_handshaker_destroy, +}; + +/* --- tsi_ssl_handshaker_factory common methods. --- */ + +tsi_result tsi_ssl_handshaker_factory_create_handshaker( + tsi_ssl_handshaker_factory *self, const char *server_name_indication, + tsi_handshaker **handshaker) { + if (self == NULL || handshaker == NULL) return TSI_INVALID_ARGUMENT; + return self->create_handshaker(self, server_name_indication, handshaker); +} + +void tsi_ssl_handshaker_factory_destroy(tsi_ssl_handshaker_factory *self) { + if (self == NULL) return; + self->destroy(self); +} + +static tsi_result create_tsi_ssl_handshaker(SSL_CTX *ctx, int is_client, + const char *server_name_indication, + tsi_handshaker **handshaker) { + SSL *ssl = SSL_new(ctx); + BIO *into_ssl = NULL; + BIO *from_ssl = NULL; + tsi_ssl_handshaker *impl = NULL; + *handshaker = NULL; + if (ctx == NULL) { + gpr_log(GPR_ERROR, "SSL Context is null. Should never happen."); + return TSI_INTERNAL_ERROR; + } + if (ssl == NULL) { + return TSI_OUT_OF_RESOURCES; + } + SSL_set_info_callback(ssl, ssl_info_callback); + + into_ssl = BIO_new(BIO_s_mem()); + from_ssl = BIO_new(BIO_s_mem()); + if (into_ssl == NULL || from_ssl == NULL) { + gpr_log(GPR_ERROR, "BIO_new failed."); + SSL_free(ssl); + if (into_ssl != NULL) BIO_free(into_ssl); + if (from_ssl != NULL) BIO_free(into_ssl); + return TSI_OUT_OF_RESOURCES; + } + SSL_set_bio(ssl, into_ssl, from_ssl); + if (is_client) { + int ssl_result; + SSL_set_connect_state(ssl); + if (server_name_indication != NULL) { + if (!SSL_set_tlsext_host_name(ssl, server_name_indication)) { + gpr_log(GPR_ERROR, "Invalid server name indication %s.", + server_name_indication); + SSL_free(ssl); + return TSI_INTERNAL_ERROR; + } + } + ssl_result = SSL_do_handshake(ssl); + ssl_result = SSL_get_error(ssl, ssl_result); + if (ssl_result != SSL_ERROR_WANT_READ) { + gpr_log(GPR_ERROR, + "Unexpected error received from first SSL_do_handshake call: %s", + ssl_error_string(ssl_result)); + SSL_free(ssl); + return TSI_INTERNAL_ERROR; + } + } else { + SSL_set_accept_state(ssl); + } + + impl = gpr_zalloc(sizeof(*impl)); + impl->ssl = ssl; + impl->into_ssl = into_ssl; + impl->from_ssl = from_ssl; + impl->result = TSI_HANDSHAKE_IN_PROGRESS; + impl->base.vtable = &handshaker_vtable; + *handshaker = &impl->base; + return TSI_OK; +} + +static int select_protocol_list(const unsigned char **out, + unsigned char *outlen, + const unsigned char *client_list, + size_t client_list_len, + const unsigned char *server_list, + size_t server_list_len) { + const unsigned char *client_current = client_list; + while ((unsigned int)(client_current - client_list) < client_list_len) { + unsigned char client_current_len = *(client_current++); + const unsigned char *server_current = server_list; + while ((server_current >= server_list) && + (uintptr_t)(server_current - server_list) < server_list_len) { + unsigned char server_current_len = *(server_current++); + if ((client_current_len == server_current_len) && + !memcmp(client_current, server_current, server_current_len)) { + *out = server_current; + *outlen = server_current_len; + return SSL_TLSEXT_ERR_OK; + } + server_current += server_current_len; + } + client_current += client_current_len; + } + return SSL_TLSEXT_ERR_NOACK; +} + +/* --- tsi_ssl__client_handshaker_factory methods implementation. --- */ + +static tsi_result ssl_client_handshaker_factory_create_handshaker( + tsi_ssl_handshaker_factory *self, const char *server_name_indication, + tsi_handshaker **handshaker) { + tsi_ssl_client_handshaker_factory *impl = + (tsi_ssl_client_handshaker_factory *)self; + return create_tsi_ssl_handshaker(impl->ssl_context, 1, server_name_indication, + handshaker); +} + +static void ssl_client_handshaker_factory_destroy( + tsi_ssl_handshaker_factory *self) { + tsi_ssl_client_handshaker_factory *impl = + (tsi_ssl_client_handshaker_factory *)self; + if (impl->ssl_context != NULL) SSL_CTX_free(impl->ssl_context); + if (impl->alpn_protocol_list != NULL) gpr_free(impl->alpn_protocol_list); + gpr_free(impl); +} + +static int client_handshaker_factory_npn_callback(SSL *ssl, unsigned char **out, + unsigned char *outlen, + const unsigned char *in, + unsigned int inlen, + void *arg) { + tsi_ssl_client_handshaker_factory *factory = + (tsi_ssl_client_handshaker_factory *)arg; + return select_protocol_list((const unsigned char **)out, outlen, + factory->alpn_protocol_list, + factory->alpn_protocol_list_length, in, inlen); +} + +/* --- tsi_ssl_server_handshaker_factory methods implementation. --- */ + +static tsi_result ssl_server_handshaker_factory_create_handshaker( + tsi_ssl_handshaker_factory *self, const char *server_name_indication, + tsi_handshaker **handshaker) { + tsi_ssl_server_handshaker_factory *impl = + (tsi_ssl_server_handshaker_factory *)self; + if (impl->ssl_context_count == 0 || server_name_indication != NULL) { + return TSI_INVALID_ARGUMENT; + } + /* Create the handshaker with the first context. We will switch if needed + because of SNI in ssl_server_handshaker_factory_servername_callback. */ + return create_tsi_ssl_handshaker(impl->ssl_contexts[0], 0, NULL, handshaker); +} + +static void ssl_server_handshaker_factory_destroy( + tsi_ssl_handshaker_factory *self) { + tsi_ssl_server_handshaker_factory *impl = + (tsi_ssl_server_handshaker_factory *)self; + size_t i; + for (i = 0; i < impl->ssl_context_count; i++) { + if (impl->ssl_contexts[i] != NULL) { + SSL_CTX_free(impl->ssl_contexts[i]); + tsi_peer_destruct(&impl->ssl_context_x509_subject_names[i]); + } + } + if (impl->ssl_contexts != NULL) gpr_free(impl->ssl_contexts); + if (impl->ssl_context_x509_subject_names != NULL) { + gpr_free(impl->ssl_context_x509_subject_names); + } + if (impl->alpn_protocol_list != NULL) gpr_free(impl->alpn_protocol_list); + gpr_free(impl); +} + +static int does_entry_match_name(const char *entry, size_t entry_length, + const char *name) { + const char *dot; + const char *name_subdomain = NULL; + size_t name_length = strlen(name); + size_t name_subdomain_length; + if (entry_length == 0) return 0; + + /* Take care of '.' terminations. */ + if (name[name_length - 1] == '.') { + name_length--; + } + if (entry[entry_length - 1] == '.') { + entry_length--; + if (entry_length == 0) return 0; + } + + if ((name_length == entry_length) && + strncmp(name, entry, entry_length) == 0) { + return 1; /* Perfect match. */ + } + if (entry[0] != '*') return 0; + + /* Wildchar subdomain matching. */ + if (entry_length < 3 || entry[1] != '.') { /* At least *.x */ + gpr_log(GPR_ERROR, "Invalid wildchar entry."); + return 0; + } + name_subdomain = strchr(name, '.'); + if (name_subdomain == NULL) return 0; + name_subdomain_length = strlen(name_subdomain); + if (name_subdomain_length < 2) return 0; + name_subdomain++; /* Starts after the dot. */ + name_subdomain_length--; + entry += 2; /* Remove *. */ + entry_length -= 2; + dot = strchr(name_subdomain, '.'); + if ((dot == NULL) || (dot == &name_subdomain[name_subdomain_length - 1])) { + gpr_log(GPR_ERROR, "Invalid toplevel subdomain: %s", name_subdomain); + return 0; + } + if (name_subdomain[name_subdomain_length - 1] == '.') { + name_subdomain_length--; + } + return ((entry_length > 0) && (name_subdomain_length == entry_length) && + strncmp(entry, name_subdomain, entry_length) == 0); +} + +static int ssl_server_handshaker_factory_servername_callback(SSL *ssl, int *ap, + void *arg) { + tsi_ssl_server_handshaker_factory *impl = + (tsi_ssl_server_handshaker_factory *)arg; + size_t i = 0; + const char *servername = SSL_get_servername(ssl, TLSEXT_NAMETYPE_host_name); + if (servername == NULL || strlen(servername) == 0) { + return SSL_TLSEXT_ERR_NOACK; + } + + for (i = 0; i < impl->ssl_context_count; i++) { + if (tsi_ssl_peer_matches_name(&impl->ssl_context_x509_subject_names[i], + servername)) { + SSL_set_SSL_CTX(ssl, impl->ssl_contexts[i]); + return SSL_TLSEXT_ERR_OK; + } + } + gpr_log(GPR_ERROR, "No match found for server name: %s.", servername); + return SSL_TLSEXT_ERR_ALERT_WARNING; +} + +#if TSI_OPENSSL_ALPN_SUPPORT +static int server_handshaker_factory_alpn_callback( + SSL *ssl, const unsigned char **out, unsigned char *outlen, + const unsigned char *in, unsigned int inlen, void *arg) { + tsi_ssl_server_handshaker_factory *factory = + (tsi_ssl_server_handshaker_factory *)arg; + return select_protocol_list(out, outlen, in, inlen, + factory->alpn_protocol_list, + factory->alpn_protocol_list_length); +} +#endif /* TSI_OPENSSL_ALPN_SUPPORT */ + +static int server_handshaker_factory_npn_advertised_callback( + SSL *ssl, const unsigned char **out, unsigned int *outlen, void *arg) { + tsi_ssl_server_handshaker_factory *factory = + (tsi_ssl_server_handshaker_factory *)arg; + *out = factory->alpn_protocol_list; + GPR_ASSERT(factory->alpn_protocol_list_length <= UINT_MAX); + *outlen = (unsigned int)factory->alpn_protocol_list_length; + return SSL_TLSEXT_ERR_OK; +} + +/* --- tsi_ssl_handshaker_factory constructors. --- */ + +tsi_result tsi_create_ssl_client_handshaker_factory( + const unsigned char *pem_private_key, size_t pem_private_key_size, + const unsigned char *pem_cert_chain, size_t pem_cert_chain_size, + const unsigned char *pem_root_certs, size_t pem_root_certs_size, + const char *cipher_list, const unsigned char **alpn_protocols, + const unsigned char *alpn_protocols_lengths, uint16_t num_alpn_protocols, + tsi_ssl_handshaker_factory **factory) { + SSL_CTX *ssl_context = NULL; + tsi_ssl_client_handshaker_factory *impl = NULL; + tsi_result result = TSI_OK; + + gpr_once_init(&init_openssl_once, init_openssl); + + if (factory == NULL) return TSI_INVALID_ARGUMENT; + *factory = NULL; + if (pem_root_certs == NULL) return TSI_INVALID_ARGUMENT; + + ssl_context = SSL_CTX_new(TLSv1_2_method()); + if (ssl_context == NULL) { + gpr_log(GPR_ERROR, "Could not create ssl context."); + return TSI_INVALID_ARGUMENT; + } + + impl = gpr_zalloc(sizeof(*impl)); + impl->ssl_context = ssl_context; + + do { + result = + populate_ssl_context(ssl_context, pem_private_key, pem_private_key_size, + pem_cert_chain, pem_cert_chain_size, cipher_list); + if (result != TSI_OK) break; + result = ssl_ctx_load_verification_certs(ssl_context, pem_root_certs, + pem_root_certs_size, NULL); + if (result != TSI_OK) { + gpr_log(GPR_ERROR, "Cannot load server root certificates."); + break; + } + + if (num_alpn_protocols != 0) { + result = build_alpn_protocol_name_list( + alpn_protocols, alpn_protocols_lengths, num_alpn_protocols, + &impl->alpn_protocol_list, &impl->alpn_protocol_list_length); + if (result != TSI_OK) { + gpr_log(GPR_ERROR, "Building alpn list failed with error %s.", + tsi_result_to_string(result)); + break; + } +#if TSI_OPENSSL_ALPN_SUPPORT + GPR_ASSERT(impl->alpn_protocol_list_length < UINT_MAX); + if (SSL_CTX_set_alpn_protos( + ssl_context, impl->alpn_protocol_list, + (unsigned int)impl->alpn_protocol_list_length)) { + gpr_log(GPR_ERROR, "Could not set alpn protocol list to context."); + result = TSI_INVALID_ARGUMENT; + break; + } +#endif /* TSI_OPENSSL_ALPN_SUPPORT */ + SSL_CTX_set_next_proto_select_cb( + ssl_context, client_handshaker_factory_npn_callback, impl); + } + } while (0); + if (result != TSI_OK) { + ssl_client_handshaker_factory_destroy(&impl->base); + return result; + } + SSL_CTX_set_verify(ssl_context, SSL_VERIFY_PEER, NULL); + /* TODO(jboeuf): Add revocation verification. */ + + impl->base.create_handshaker = + ssl_client_handshaker_factory_create_handshaker; + impl->base.destroy = ssl_client_handshaker_factory_destroy; + *factory = &impl->base; + return TSI_OK; +} + +tsi_result tsi_create_ssl_server_handshaker_factory( + const unsigned char **pem_private_keys, + const size_t *pem_private_keys_sizes, const unsigned char **pem_cert_chains, + const size_t *pem_cert_chains_sizes, size_t key_cert_pair_count, + const unsigned char *pem_client_root_certs, + size_t pem_client_root_certs_size, int force_client_auth, + const char *cipher_list, const unsigned char **alpn_protocols, + const unsigned char *alpn_protocols_lengths, uint16_t num_alpn_protocols, + tsi_ssl_handshaker_factory **factory) { + return tsi_create_ssl_server_handshaker_factory_ex( + pem_private_keys, pem_private_keys_sizes, pem_cert_chains, + pem_cert_chains_sizes, key_cert_pair_count, pem_client_root_certs, + pem_client_root_certs_size, + force_client_auth ? TSI_REQUEST_AND_REQUIRE_CLIENT_CERTIFICATE_AND_VERIFY + : TSI_DONT_REQUEST_CLIENT_CERTIFICATE, + cipher_list, alpn_protocols, alpn_protocols_lengths, num_alpn_protocols, + factory); +} + +tsi_result tsi_create_ssl_server_handshaker_factory_ex( + const unsigned char **pem_private_keys, + const size_t *pem_private_keys_sizes, const unsigned char **pem_cert_chains, + const size_t *pem_cert_chains_sizes, size_t key_cert_pair_count, + const unsigned char *pem_client_root_certs, + size_t pem_client_root_certs_size, + tsi_client_certificate_request_type client_certificate_request, + const char *cipher_list, const unsigned char **alpn_protocols, + const unsigned char *alpn_protocols_lengths, uint16_t num_alpn_protocols, + tsi_ssl_handshaker_factory **factory) { + tsi_ssl_server_handshaker_factory *impl = NULL; + tsi_result result = TSI_OK; + size_t i = 0; + + gpr_once_init(&init_openssl_once, init_openssl); + + if (factory == NULL) return TSI_INVALID_ARGUMENT; + *factory = NULL; + if (key_cert_pair_count == 0 || pem_private_keys == NULL || + pem_cert_chains == NULL) { + return TSI_INVALID_ARGUMENT; + } + + impl = gpr_zalloc(sizeof(*impl)); + impl->base.create_handshaker = + ssl_server_handshaker_factory_create_handshaker; + impl->base.destroy = ssl_server_handshaker_factory_destroy; + impl->ssl_contexts = gpr_zalloc(key_cert_pair_count * sizeof(SSL_CTX *)); + impl->ssl_context_x509_subject_names = + gpr_zalloc(key_cert_pair_count * sizeof(tsi_peer)); + if (impl->ssl_contexts == NULL || + impl->ssl_context_x509_subject_names == NULL) { + tsi_ssl_handshaker_factory_destroy(&impl->base); + return TSI_OUT_OF_RESOURCES; + } + impl->ssl_context_count = key_cert_pair_count; + + if (num_alpn_protocols > 0) { + result = build_alpn_protocol_name_list( + alpn_protocols, alpn_protocols_lengths, num_alpn_protocols, + &impl->alpn_protocol_list, &impl->alpn_protocol_list_length); + if (result != TSI_OK) { + tsi_ssl_handshaker_factory_destroy(&impl->base); + return result; + } + } + + for (i = 0; i < key_cert_pair_count; i++) { + do { + impl->ssl_contexts[i] = SSL_CTX_new(TLSv1_2_method()); + if (impl->ssl_contexts[i] == NULL) { + gpr_log(GPR_ERROR, "Could not create ssl context."); + result = TSI_OUT_OF_RESOURCES; + break; + } + result = populate_ssl_context( + impl->ssl_contexts[i], pem_private_keys[i], pem_private_keys_sizes[i], + pem_cert_chains[i], pem_cert_chains_sizes[i], cipher_list); + if (result != TSI_OK) break; + + if (pem_client_root_certs != NULL) { + STACK_OF(X509_NAME) *root_names = NULL; + result = ssl_ctx_load_verification_certs( + impl->ssl_contexts[i], pem_client_root_certs, + pem_client_root_certs_size, &root_names); + if (result != TSI_OK) { + gpr_log(GPR_ERROR, "Invalid verification certs."); + break; + } + SSL_CTX_set_client_CA_list(impl->ssl_contexts[i], root_names); + switch (client_certificate_request) { + case TSI_DONT_REQUEST_CLIENT_CERTIFICATE: + SSL_CTX_set_verify(impl->ssl_contexts[i], SSL_VERIFY_NONE, NULL); + break; + case TSI_REQUEST_CLIENT_CERTIFICATE_BUT_DONT_VERIFY: + SSL_CTX_set_verify(impl->ssl_contexts[i], SSL_VERIFY_PEER, + NullVerifyCallback); + break; + case TSI_REQUEST_CLIENT_CERTIFICATE_AND_VERIFY: + SSL_CTX_set_verify(impl->ssl_contexts[i], SSL_VERIFY_PEER, NULL); + break; + case TSI_REQUEST_AND_REQUIRE_CLIENT_CERTIFICATE_BUT_DONT_VERIFY: + SSL_CTX_set_verify( + impl->ssl_contexts[i], + SSL_VERIFY_PEER | SSL_VERIFY_FAIL_IF_NO_PEER_CERT, + NullVerifyCallback); + break; + case TSI_REQUEST_AND_REQUIRE_CLIENT_CERTIFICATE_AND_VERIFY: + SSL_CTX_set_verify( + impl->ssl_contexts[i], + SSL_VERIFY_PEER | SSL_VERIFY_FAIL_IF_NO_PEER_CERT, NULL); + break; + } + /* TODO(jboeuf): Add revocation verification. */ + } + + result = extract_x509_subject_names_from_pem_cert( + pem_cert_chains[i], pem_cert_chains_sizes[i], + &impl->ssl_context_x509_subject_names[i]); + if (result != TSI_OK) break; + + SSL_CTX_set_tlsext_servername_callback( + impl->ssl_contexts[i], + ssl_server_handshaker_factory_servername_callback); + SSL_CTX_set_tlsext_servername_arg(impl->ssl_contexts[i], impl); +#if TSI_OPENSSL_ALPN_SUPPORT + SSL_CTX_set_alpn_select_cb(impl->ssl_contexts[i], + server_handshaker_factory_alpn_callback, impl); +#endif /* TSI_OPENSSL_ALPN_SUPPORT */ + SSL_CTX_set_next_protos_advertised_cb( + impl->ssl_contexts[i], + server_handshaker_factory_npn_advertised_callback, impl); + } while (0); + + if (result != TSI_OK) { + tsi_ssl_handshaker_factory_destroy(&impl->base); + return result; + } + } + *factory = &impl->base; + return TSI_OK; +} + +/* --- tsi_ssl utils. --- */ + +int tsi_ssl_peer_matches_name(const tsi_peer *peer, const char *name) { + size_t i = 0; + size_t san_count = 0; + const tsi_peer_property *cn_property = NULL; + int like_ip = looks_like_ip_address(name); + + /* Check the SAN first. */ + for (i = 0; i < peer->property_count; i++) { + const tsi_peer_property *property = &peer->properties[i]; + if (property->name == NULL) continue; + if (strcmp(property->name, + TSI_X509_SUBJECT_ALTERNATIVE_NAME_PEER_PROPERTY) == 0) { + san_count++; + + if (!like_ip && does_entry_match_name(property->value.data, + property->value.length, name)) { + return 1; + } else if (like_ip && + strncmp(name, property->value.data, property->value.length) == + 0 && + strlen(name) == property->value.length) { + /* IP Addresses are exact matches only. */ + return 1; + } + } else if (strcmp(property->name, + TSI_X509_SUBJECT_COMMON_NAME_PEER_PROPERTY) == 0) { + cn_property = property; + } + } + + /* If there's no SAN, try the CN, but only if its not like an IP Address */ + if (san_count == 0 && cn_property != NULL && !like_ip) { + if (does_entry_match_name(cn_property->value.data, + cn_property->value.length, name)) { + return 1; + } + } + + return 0; /* Not found. */ +} |