X-Git-Url: http://www.privoxy.org/gitweb/?p=privoxy.git;a=blobdiff_plain;f=ssl.c;h=ca75c7c4f48f03278d102c29c4a082717753bf1e;hp=ef4abc68165588e6f3248beb9901223b061a25e1;hb=1c5e3bad1f2ced4e68933a833fb8fa209f3be3ef;hpb=bf5b302d96a0ea44b1a6634972d22a8f667df8fb diff --git a/ssl.c b/ssl.c index ef4abc68..ca75c7c4 100644 --- a/ssl.c +++ b/ssl.c @@ -6,7 +6,7 @@ * creating, using and closing TLS/SSL connections. * * Copyright : Written by and Copyright (c) 2017 Vaclav Svec. FIT CVUT. - * Copyright (C) 2018-2019 by Fabian Keil + * Copyright (C) 2018-2020 by Fabian Keil * * This program is free software; you can redistribute it * and/or modify it under the terms of the GNU General @@ -107,13 +107,12 @@ typedef struct { char *key_file_path; /* filename of the key file */ } key_options; -extern int generate_webpage_certificate(struct client_state *csp); +static int generate_webpage_certificate(struct client_state *csp); static char *make_certs_path(const char *conf_dir, const char *file_name, const char *suffix); static int file_exists(const char *path); static int host_to_hash(struct client_state *csp); static int ssl_verify_callback(void *data, mbedtls_x509_crt *crt, int depth, uint32_t *flags); static void free_certificate_chain(struct client_state *csp); -static unsigned int get_certificate_mutex_id(struct client_state *csp); static unsigned long get_certificate_serial(struct client_state *csp); static void free_client_ssl_structures(struct client_state *csp); static void free_server_ssl_structures(struct client_state *csp); @@ -229,6 +228,8 @@ extern int ssl_send_data(mbedtls_ssl_context *ssl, const unsigned char *buf, siz send_len = (int)max_fragment_size; } + log_error(LOG_LEVEL_WRITING, "TLS: %N", send_len, buf+pos); + /* * Sending one part of the buffer */ @@ -267,8 +268,8 @@ extern int ssl_send_data(mbedtls_ssl_context *ssl, const unsigned char *buf, siz * 2 : buf = Pointer to buffer where data will be written * 3 : max_length = Maximum number of bytes to read * - * Returns : Number of bytes read, 0 for EOF, or negative - * value on error. + * Returns : Number of bytes read, 0 for EOF, or -1 + * on error. * *********************************************************************/ extern int ssl_recv_data(mbedtls_ssl_context *ssl, unsigned char *buf, size_t max_length) @@ -289,11 +290,21 @@ extern int ssl_recv_data(mbedtls_ssl_context *ssl, unsigned char *buf, size_t ma { char err_buf[ERROR_BUF_SIZE]; + if (ret == MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY) + { + log_error(LOG_LEVEL_CONNECT, + "The peer notified us that the connection is going to be closed"); + return 0; + } mbedtls_strerror(ret, err_buf, sizeof(err_buf)); log_error(LOG_LEVEL_ERROR, "Receiving data over TLS/SSL failed: %s", err_buf); + + return -1; } + log_error(LOG_LEVEL_RECEIVED, "TLS: %N", ret, buf); + return ret; } @@ -425,19 +436,18 @@ extern int create_client_ssl_connection(struct client_state *csp) * Generating certificate for requested host. Mutex to prevent * certificate and key inconsistence must be locked. */ - unsigned int cert_mutex_id = get_certificate_mutex_id(csp); - privoxy_mutex_lock(&(certificates_mutexes[cert_mutex_id])); + privoxy_mutex_lock(&certificate_mutex); ret = generate_webpage_certificate(csp); if (ret < 0) { log_error(LOG_LEVEL_ERROR, "Generate_webpage_certificate failed: %d", ret); - privoxy_mutex_unlock(&(certificates_mutexes[cert_mutex_id])); + privoxy_mutex_unlock(&certificate_mutex); ret = -1; goto exit; } - privoxy_mutex_unlock(&(certificates_mutexes[cert_mutex_id])); + privoxy_mutex_unlock(&certificate_mutex); /* * Seed the RNG @@ -790,7 +800,7 @@ extern int create_server_ssl_connection(struct client_state *csp) * Handshake with server */ log_error(LOG_LEVEL_CONNECT, - "Performing the TLS/SSL handshake with server"); + "Performing the TLS/SSL handshake with the server"); while ((ret = mbedtls_ssl_handshake(&(csp->mbedtls_server_attr.ssl))) != 0) { @@ -801,11 +811,17 @@ extern int create_server_ssl_connection(struct client_state *csp) if (ret == MBEDTLS_ERR_X509_CERT_VERIFY_FAILED) { - log_error(LOG_LEVEL_ERROR, - "Server certificate verification failed: %s", err_buf); + char reason[INVALID_CERT_INFO_BUF_SIZE]; + csp->server_cert_verification_result = mbedtls_ssl_get_verify_result(&(csp->mbedtls_server_attr.ssl)); + mbedtls_x509_crt_verify_info(reason, sizeof(reason), "", + csp->server_cert_verification_result); + /* Log the reason without the trailing new line */ + log_error(LOG_LEVEL_ERROR, + "X509 certificate verification for %s failed: %N", + csp->http->hostport, strlen(reason)-1, reason); ret = -1; } else @@ -895,7 +911,7 @@ static void free_server_ssl_structures(struct client_state *csp) * function, we change fd to -1, which is the same what does * rest of mbedtls_net_free function. */ - csp->mbedtls_client_attr.socket_fd.fd = -1; + csp->mbedtls_server_attr.socket_fd.fd = -1; mbedtls_x509_crt_free(&(csp->mbedtls_server_attr.ca_cert)); mbedtls_ssl_free(&(csp->mbedtls_server_attr.ssl)); @@ -1085,15 +1101,15 @@ exit: * contain NULL and no private key is generated. * * Parameters : - * 1 : key_buf = buffer to save new generated key - * 2 : csp = Current client state (buffers, headers, etc...) + * 1 : csp = Current client state (buffers, headers, etc...) + * 2 : key_buf = buffer to save new generated key * * Returns : -1 => Error while generating private key * 0 => Key already exists * >0 => Length of generated private key * *********************************************************************/ -static int generate_key(unsigned char **key_buf, struct client_state *csp) +static int generate_key(struct client_state *csp, unsigned char **key_buf) { mbedtls_pk_context key; key_options key_opt; @@ -1185,6 +1201,55 @@ exit: } +/********************************************************************* + * + * Function : ssl_certificate_is_invalid + * + * Description : Checks whether or not a certificate is valid. + * Currently only checks that the certificate can be + * parsed and that the "valid to" date is in the future. + * + * Parameters : + * 1 : cert_file = The certificate to check + * + * Returns : 0 => The certificate is valid. + * 1 => The certificate is invalid + * + *********************************************************************/ +static int ssl_certificate_is_invalid(const char *cert_file) +{ + mbedtls_x509_crt cert; + int ret; + + mbedtls_x509_crt_init(&cert); + + ret = mbedtls_x509_crt_parse_file(&cert, cert_file); + if (ret != 0) + { + char err_buf[ERROR_BUF_SIZE]; + + mbedtls_strerror(ret, err_buf, sizeof(err_buf)); + log_error(LOG_LEVEL_ERROR, + "Loading certificate %s to check validity failed: %s", + cert_file, err_buf); + mbedtls_x509_crt_free(&cert); + + return 1; + } + if (mbedtls_x509_time_is_past(&cert.valid_to)) + { + mbedtls_x509_crt_free(&cert); + + return 1; + } + + mbedtls_x509_crt_free(&cert); + + return 0; + +} + + /********************************************************************* * * Function : generate_webpage_certificate @@ -1203,7 +1268,7 @@ exit: * >0 => Length of created certificate. * *********************************************************************/ -extern int generate_webpage_certificate(struct client_state *csp) +static int generate_webpage_certificate(struct client_state *csp) { mbedtls_x509_crt issuer_cert; mbedtls_pk_context loaded_issuer_key, loaded_subject_key; @@ -1227,7 +1292,7 @@ extern int generate_webpage_certificate(struct client_state *csp) /* * Create key for requested host */ - int subject_key_len = generate_key(&key_buf, csp); + int subject_key_len = generate_key(csp, &key_buf); if (subject_key_len < 0) { log_error(LOG_LEVEL_ERROR, "Key generating failed"); @@ -1314,8 +1379,25 @@ extern int generate_webpage_certificate(struct client_state *csp) */ if (file_exists(cert_opt.output_file) == 1 && subject_key_len == 0) { - ret = 0; - goto exit; + /* The file exists, but is it valid */ + if (ssl_certificate_is_invalid(cert_opt.output_file)) + { + log_error(LOG_LEVEL_CONNECT, + "Certificate %s is no longer valid. Removing.", + cert_opt.output_file); + if (unlink(cert_opt.output_file)) + { + log_error(LOG_LEVEL_ERROR, "Failed to unlink %s: %E", + cert_opt.output_file); + ret = -1; + goto exit; + } + } + else + { + ret = 0; + goto exit; + } } /* @@ -1534,7 +1616,7 @@ exit: * * Function : make_certs_path * - * Description : Creates path to file from three pieces. This fuction + * Description : Creates path to file from three pieces. This function * takes parameters and puts them in one new mallocated * char * in correct order. Returned variable must be freed * by caller. This function is mainly used for creating @@ -1609,29 +1691,6 @@ static char *make_certs_path(const char *conf_dir, const char *file_name, } -/********************************************************************* - * - * Function : get_certificate_mutex_id - * - * Description : Computes mutex id from host name hash. This hash must - * be already saved in csp structure - * - * Parameters : - * 1 : csp = Current client state (buffers, headers, etc...) - * - * Returns : Mutex id for given host name - * - *********************************************************************/ -static unsigned int get_certificate_mutex_id(struct client_state *csp) { -#ifdef LIMIT_MUTEX_NUMBER - return (unsigned int)(csp->http->hash_of_host[0] % 32); -#else - return (unsigned int)(csp->http->hash_of_host[1] - + 256 * (int)csp->http->hash_of_host[0]); -#endif /* LIMIT_MUTEX_NUMBER */ -} - - /********************************************************************* * * Function : get_certificate_serial @@ -1646,7 +1705,8 @@ static unsigned int get_certificate_mutex_id(struct client_state *csp) { * Returns : Serial number for new certificate * *********************************************************************/ -static unsigned long get_certificate_serial(struct client_state *csp) { +static unsigned long get_certificate_serial(struct client_state *csp) +{ unsigned long exp = 1; unsigned long serial = 0; @@ -1695,7 +1755,7 @@ extern void ssl_send_certificate_error(struct client_state *csp) "HTTP/1.1 200 OK\r\n" "Content-Type: text/html\r\n" "Connection: close\r\n\r\n" - "

Invalid server certificate

Reason: "; + "

Server certificate verification failed

Reason: "; const char message_end[] = "\r\n\r\n"; char reason[INVALID_CERT_INFO_BUF_SIZE]; memset(reason, 0, sizeof(reason)); @@ -1770,11 +1830,6 @@ extern void ssl_send_certificate_error(struct client_state *csp) */ ssl_send_data(&(csp->mbedtls_client_attr.ssl), (const unsigned char *)message, strlen(message)); - /* - * Waiting before closing connection. Some browsers don't show received - * message if there isn't this delay. - */ - sleep(1); free_certificate_chain(csp); } @@ -1864,7 +1919,7 @@ static void free_certificate_chain(struct client_state *csp) /* Cleaning buffers */ memset(csp->server_certs_chain.text_buf, 0, sizeof(csp->server_certs_chain.text_buf)); - memset(csp->server_certs_chain.text_buf, 0, + memset(csp->server_certs_chain.file_buf, 0, sizeof(csp->server_certs_chain.file_buf)); csp->server_certs_chain.next = NULL; @@ -1926,9 +1981,7 @@ static int host_to_hash(struct client_state *csp) int ret = 0; #if !defined(MBEDTLS_MD5_C) - log_error(LOG_LEVEL_ERROR, "MBEDTLS_MD5_C is not defined. Can't create" - "MD5 hash for certificate and key name."); - return -1; +#error mbedTLS needs to be compiled with md5 support #else memset(csp->http->hash_of_host, 0, sizeof(csp->http->hash_of_host)); mbedtls_md5((unsigned char *)csp->http->host, strlen(csp->http->host),