/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) * All rights reserved. * * This package is an SSL implementation written * by Eric Young (eay@cryptsoft.com). * The implementation was written so as to conform with Netscapes SSL. * * This library is free for commercial and non-commercial use as long as * the following conditions are aheared to. The following conditions * apply to all code found in this distribution, be it the RC4, RSA, * lhash, DES, etc., code; not just the SSL code. The SSL documentation * included with this distribution is covered by the same copyright terms * except that the holder is Tim Hudson (tjh@cryptsoft.com). * * Copyright remains Eric Young's, and as such any Copyright notices in * the code are not to be removed. * If this package is used in a product, Eric Young should be given attribution * as the author of the parts of the library used. * This can be in the form of a textual message at program startup or * in documentation (online or textual) provided with the package. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the copyright * notice, this list of conditions and the following disclaimer. * 2. 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. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * "This product includes cryptographic software written by * Eric Young (eay@cryptsoft.com)" * The word 'cryptographic' can be left out if the rouines from the library * being used are not cryptographic related :-). * 4. If you include any Windows specific code (or a derivative thereof) from * the apps directory (application code) you must include an acknowledgement: * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" * * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``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 AUTHOR 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. * * The licence and distribution terms for any publically available version or * derivative of this code cannot be changed. i.e. this code cannot simply be * copied and put under another distribution licence * [including the GNU Public Licence.] */ /* ==================================================================== * Copyright (c) 1998-2002 The OpenSSL Project. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. 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. * * 3. All advertising materials mentioning features or use of this * software must display the following acknowledgment: * "This product includes software developed by the OpenSSL Project * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" * * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to * endorse or promote products derived from this software without * prior written permission. For written permission, please contact * openssl-core@openssl.org. * * 5. Products derived from this software may not be called "OpenSSL" * nor may "OpenSSL" appear in their names without prior written * permission of the OpenSSL Project. * * 6. Redistributions of any form whatsoever must retain the following * acknowledgment: * "This product includes software developed by the OpenSSL Project * for use in the OpenSSL Toolkit (http://www.openssl.org/)" * * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY * EXPRESSED 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 OpenSSL PROJECT OR * ITS 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. * ==================================================================== * * This product includes cryptographic software written by Eric Young * (eay@cryptsoft.com). This product includes software written by Tim * Hudson (tjh@cryptsoft.com). */ #include #include #include #include #include #include #include #include #include #include "internal.h" static int do_ssl3_write(SSL *ssl, int type, const uint8_t *buf, unsigned len); /* kMaxWarningAlerts is the number of consecutive warning alerts that will be * processed. */ static const uint8_t kMaxWarningAlerts = 4; /* ssl3_get_record reads a new input record. On success, it places it in * |ssl->s3->rrec| and returns one. Otherwise it returns <= 0 on error or if * more data is needed. */ static int ssl3_get_record(SSL *ssl) { int ret; again: /* Ensure the buffer is large enough to decrypt in-place. */ ret = ssl_read_buffer_extend_to(ssl, ssl_record_prefix_len(ssl)); if (ret <= 0) { return ret; } assert(ssl_read_buffer_len(ssl) >= ssl_record_prefix_len(ssl)); uint8_t *out = ssl_read_buffer(ssl) + ssl_record_prefix_len(ssl); size_t max_out = ssl_read_buffer_len(ssl) - ssl_record_prefix_len(ssl); uint8_t type, alert; size_t len, consumed; switch (tls_open_record(ssl, &type, out, &len, &consumed, &alert, max_out, ssl_read_buffer(ssl), ssl_read_buffer_len(ssl))) { case ssl_open_record_success: ssl_read_buffer_consume(ssl, consumed); if (len > 0xffff) { OPENSSL_PUT_ERROR(SSL, ERR_R_OVERFLOW); return -1; } SSL3_RECORD *rr = &ssl->s3->rrec; rr->type = type; rr->length = (uint16_t)len; rr->data = out; return 1; case ssl_open_record_partial: ret = ssl_read_buffer_extend_to(ssl, consumed); if (ret <= 0) { return ret; } goto again; case ssl_open_record_discard: ssl_read_buffer_consume(ssl, consumed); goto again; case ssl_open_record_error: ssl3_send_alert(ssl, SSL3_AL_FATAL, alert); return -1; } assert(0); OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); return -1; } int ssl3_write_app_data(SSL *ssl, const void *buf, int len) { assert(!SSL_in_init(ssl) || SSL_in_false_start(ssl)); return ssl3_write_bytes(ssl, SSL3_RT_APPLICATION_DATA, buf, len); } /* Call this to write data in records of type |type|. It will return <= 0 if * not all data has been sent or non-blocking IO. */ int ssl3_write_bytes(SSL *ssl, int type, const void *buf_, int len) { const uint8_t *buf = buf_; unsigned tot, n, nw; ssl->rwstate = SSL_NOTHING; assert(ssl->s3->wnum <= INT_MAX); tot = ssl->s3->wnum; ssl->s3->wnum = 0; /* Ensure that if we end up with a smaller value of data to write out than * the the original len from a write which didn't complete for non-blocking * I/O and also somehow ended up avoiding the check for this in * ssl3_write_pending/SSL_R_BAD_WRITE_RETRY as it must never be possible to * end up with (len-tot) as a large number that will then promptly send * beyond the end of the users buffer ... so we trap and report the error in * a way the user will notice. */ if (len < 0 || (size_t)len < tot) { OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_LENGTH); return -1; } n = (len - tot); for (;;) { /* max contains the maximum number of bytes that we can put into a * record. */ unsigned max = ssl->max_send_fragment; if (n > max) { nw = max; } else { nw = n; } int ret = do_ssl3_write(ssl, type, &buf[tot], nw); if (ret <= 0) { ssl->s3->wnum = tot; return ret; } if (ret == (int)n || (type == SSL3_RT_APPLICATION_DATA && (ssl->mode & SSL_MODE_ENABLE_PARTIAL_WRITE))) { return tot + ret; } n -= ret; tot += ret; } } static int ssl3_write_pending(SSL *ssl, int type, const uint8_t *buf, unsigned int len) { if (ssl->s3->wpend_tot > (int)len || (ssl->s3->wpend_buf != buf && !(ssl->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER)) || ssl->s3->wpend_type != type) { OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_WRITE_RETRY); return -1; } int ret = ssl_write_buffer_flush(ssl); if (ret <= 0) { return ret; } return ssl->s3->wpend_ret; } /* do_ssl3_write writes an SSL record of the given type. */ static int do_ssl3_write(SSL *ssl, int type, const uint8_t *buf, unsigned len) { /* If there is still data from the previous record, flush it. */ if (ssl_write_buffer_is_pending(ssl)) { return ssl3_write_pending(ssl, type, buf, len); } /* If we have an alert to send, lets send it */ if (ssl->s3->alert_dispatch) { int ret = ssl->method->ssl_dispatch_alert(ssl); if (ret <= 0) { return ret; } /* if it went, fall through and send more stuff */ } if (len > SSL3_RT_MAX_PLAIN_LENGTH) { OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); return -1; } if (len == 0) { return 0; } size_t max_out = len + ssl_max_seal_overhead(ssl); if (max_out < len) { OPENSSL_PUT_ERROR(SSL, ERR_R_OVERFLOW); return -1; } uint8_t *out; size_t ciphertext_len; if (!ssl_write_buffer_init(ssl, &out, max_out) || !tls_seal_record(ssl, out, &ciphertext_len, max_out, type, buf, len)) { return -1; } ssl_write_buffer_set_len(ssl, ciphertext_len); /* memorize arguments so that ssl3_write_pending can detect bad write retries * later */ ssl->s3->wpend_tot = len; ssl->s3->wpend_buf = buf; ssl->s3->wpend_type = type; ssl->s3->wpend_ret = len; /* we now just need to write the buffer */ return ssl3_write_pending(ssl, type, buf, len); } int ssl3_read_app_data(SSL *ssl, uint8_t *buf, int len, int peek) { assert(!SSL_in_init(ssl)); return ssl3_read_bytes(ssl, SSL3_RT_APPLICATION_DATA, buf, len, peek); } int ssl3_read_change_cipher_spec(SSL *ssl) { uint8_t byte; int ret = ssl3_read_bytes(ssl, SSL3_RT_CHANGE_CIPHER_SPEC, &byte, 1 /* len */, 0 /* no peek */); if (ret <= 0) { return ret; } assert(ret == 1); if (ssl->s3->rrec.length != 0 || byte != SSL3_MT_CCS) { OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_CHANGE_CIPHER_SPEC); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); return -1; } if (ssl->msg_callback != NULL) { ssl->msg_callback(0, ssl->version, SSL3_RT_CHANGE_CIPHER_SPEC, &byte, 1, ssl, ssl->msg_callback_arg); } return 1; } void ssl3_read_close_notify(SSL *ssl) { ssl3_read_bytes(ssl, 0, NULL, 0, 0); } static int ssl3_can_renegotiate(SSL *ssl) { switch (ssl->renegotiate_mode) { case ssl_renegotiate_never: return 0; case ssl_renegotiate_once: return ssl->s3->total_renegotiations == 0; case ssl_renegotiate_freely: return 1; case ssl_renegotiate_ignore: return 1; } assert(0); return 0; } /* Return up to 'len' payload bytes received in 'type' records. * 'type' is one of the following: * * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us) * - SSL3_RT_CHANGE_CIPHER_SPEC (when ssl3_read_change_cipher_spec calls us) * - SSL3_RT_APPLICATION_DATA (when ssl3_read_app_data calls us) * - 0 (during a shutdown, no data has to be returned) * * If we don't have stored data to work from, read a SSL/TLS record first * (possibly multiple records if we still don't have anything to return). * * This function must handle any surprises the peer may have for us, such as * Alert records (e.g. close_notify) or renegotiation requests. */ int ssl3_read_bytes(SSL *ssl, int type, uint8_t *buf, int len, int peek) { int al, i, ret; unsigned int n; SSL3_RECORD *rr; void (*cb)(const SSL *ssl, int type, int value) = NULL; if ((type && type != SSL3_RT_APPLICATION_DATA && type != SSL3_RT_HANDSHAKE && type != SSL3_RT_CHANGE_CIPHER_SPEC) || (peek && type != SSL3_RT_APPLICATION_DATA)) { OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); return -1; } start: ssl->rwstate = SSL_NOTHING; /* ssl->s3->rrec.type - is the type of record * ssl->s3->rrec.data - data * ssl->s3->rrec.off - offset into 'data' for next read * ssl->s3->rrec.length - number of bytes. */ rr = &ssl->s3->rrec; /* get new packet if necessary */ if (rr->length == 0) { ret = ssl3_get_record(ssl); if (ret <= 0) { return ret; } } /* we now have a packet which can be read and processed */ /* If the other end has shut down, throw anything we read away (even in * 'peek' mode) */ if (ssl->shutdown & SSL_RECEIVED_SHUTDOWN) { rr->length = 0; ssl->rwstate = SSL_NOTHING; return 0; } if (type != 0 && type == rr->type) { ssl->s3->warning_alert_count = 0; /* Make sure that we are not getting application data when we are doing a * handshake for the first time. */ if (SSL_in_init(ssl) && type == SSL3_RT_APPLICATION_DATA && ssl->s3->aead_read_ctx == NULL) { /* TODO(davidben): Is this check redundant with the handshake_func * check? */ al = SSL_AD_UNEXPECTED_MESSAGE; OPENSSL_PUT_ERROR(SSL, SSL_R_APP_DATA_IN_HANDSHAKE); goto f_err; } /* Discard empty records. */ if (rr->length == 0) { goto start; } if (len <= 0) { return len; } if ((unsigned int)len > rr->length) { n = rr->length; } else { n = (unsigned int)len; } memcpy(buf, rr->data, n); if (!peek) { rr->length -= n; rr->data += n; if (rr->length == 0) { /* The record has been consumed, so we may now clear the buffer. */ ssl_read_buffer_discard(ssl); } } return n; } /* Process unexpected records. */ if (type == SSL3_RT_APPLICATION_DATA && rr->type == SSL3_RT_HANDSHAKE) { /* If peer renegotiations are disabled, all out-of-order handshake records * are fatal. Renegotiations as a server are never supported. */ if (ssl->server || !ssl3_can_renegotiate(ssl)) { al = SSL_AD_NO_RENEGOTIATION; OPENSSL_PUT_ERROR(SSL, SSL_R_NO_RENEGOTIATION); goto f_err; } /* This must be a HelloRequest, possibly fragmented over multiple records. * Consume data from the handshake protocol until it is complete. */ static const uint8_t kHelloRequest[] = {SSL3_MT_HELLO_REQUEST, 0, 0, 0}; while (ssl->s3->hello_request_len < sizeof(kHelloRequest)) { if (rr->length == 0) { /* Get a new record. */ goto start; } if (rr->data[0] != kHelloRequest[ssl->s3->hello_request_len]) { al = SSL_AD_DECODE_ERROR; OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_HELLO_REQUEST); goto f_err; } rr->data++; rr->length--; ssl->s3->hello_request_len++; } ssl->s3->hello_request_len = 0; if (ssl->msg_callback) { ssl->msg_callback(0, ssl->version, SSL3_RT_HANDSHAKE, kHelloRequest, sizeof(kHelloRequest), ssl, ssl->msg_callback_arg); } if (!SSL_is_init_finished(ssl) || !ssl->s3->initial_handshake_complete) { /* This cannot happen. If a handshake is in progress, |type| must be * |SSL3_RT_HANDSHAKE|. */ assert(0); OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); goto err; } if (ssl->renegotiate_mode == ssl_renegotiate_ignore) { goto start; } /* Renegotiation is only supported at quiescent points in the application * protocol, namely in HTTPS, just before reading the HTTP response. Require * the record-layer be idle and avoid complexities of sending a handshake * record while an application_data record is being written. */ if (ssl_write_buffer_is_pending(ssl)) { al = SSL_AD_NO_RENEGOTIATION; OPENSSL_PUT_ERROR(SSL, SSL_R_NO_RENEGOTIATION); goto f_err; } /* Begin a new handshake. */ ssl->s3->total_renegotiations++; ssl->state = SSL_ST_CONNECT; i = ssl->handshake_func(ssl); if (i < 0) { return i; } if (i == 0) { OPENSSL_PUT_ERROR(SSL, SSL_R_SSL_HANDSHAKE_FAILURE); return -1; } /* The handshake completed synchronously. Continue reading records. */ goto start; } /* If an alert record, process one alert out of the record. Note that we allow * a single record to contain multiple alerts. */ if (rr->type == SSL3_RT_ALERT) { /* Alerts may not be fragmented. */ if (rr->length < 2) { al = SSL_AD_DECODE_ERROR; OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_ALERT); goto f_err; } if (ssl->msg_callback) { ssl->msg_callback(0, ssl->version, SSL3_RT_ALERT, rr->data, 2, ssl, ssl->msg_callback_arg); } const uint8_t alert_level = rr->data[0]; const uint8_t alert_descr = rr->data[1]; rr->length -= 2; rr->data += 2; if (ssl->info_callback != NULL) { cb = ssl->info_callback; } else if (ssl->ctx->info_callback != NULL) { cb = ssl->ctx->info_callback; } if (cb != NULL) { uint16_t alert = (alert_level << 8) | alert_descr; cb(ssl, SSL_CB_READ_ALERT, alert); } if (alert_level == SSL3_AL_WARNING) { if (alert_descr == SSL_AD_CLOSE_NOTIFY) { ssl->s3->clean_shutdown = 1; ssl->shutdown |= SSL_RECEIVED_SHUTDOWN; return 0; } /* This is a warning but we receive it if we requested renegotiation and * the peer denied it. Terminate with a fatal alert because if * application tried to renegotiatie it presumably had a good reason and * expects it to succeed. * * In future we might have a renegotiation where we don't care if the * peer refused it where we carry on. */ else if (alert_descr == SSL_AD_NO_RENEGOTIATION) { al = SSL_AD_HANDSHAKE_FAILURE; OPENSSL_PUT_ERROR(SSL, SSL_R_NO_RENEGOTIATION); goto f_err; } ssl->s3->warning_alert_count++; if (ssl->s3->warning_alert_count > kMaxWarningAlerts) { al = SSL_AD_UNEXPECTED_MESSAGE; OPENSSL_PUT_ERROR(SSL, SSL_R_TOO_MANY_WARNING_ALERTS); goto f_err; } } else if (alert_level == SSL3_AL_FATAL) { char tmp[16]; ssl->rwstate = SSL_NOTHING; OPENSSL_PUT_ERROR(SSL, SSL_AD_REASON_OFFSET + alert_descr); BIO_snprintf(tmp, sizeof(tmp), "%d", alert_descr); ERR_add_error_data(2, "SSL alert number ", tmp); ssl->shutdown |= SSL_RECEIVED_SHUTDOWN; SSL_CTX_remove_session(ssl->ctx, ssl->session); return 0; } else { al = SSL_AD_ILLEGAL_PARAMETER; OPENSSL_PUT_ERROR(SSL, SSL_R_UNKNOWN_ALERT_TYPE); goto f_err; } goto start; } if (ssl->shutdown & SSL_SENT_SHUTDOWN) { /* close_notify has been sent, so discard all records other than alerts. */ rr->length = 0; goto start; } al = SSL_AD_UNEXPECTED_MESSAGE; OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_RECORD); f_err: ssl3_send_alert(ssl, SSL3_AL_FATAL, al); err: return -1; } int ssl3_send_alert(SSL *ssl, int level, int desc) { /* If a fatal one, remove from cache */ if (level == 2 && ssl->session != NULL) { SSL_CTX_remove_session(ssl->ctx, ssl->session); } ssl->s3->alert_dispatch = 1; ssl->s3->send_alert[0] = level; ssl->s3->send_alert[1] = desc; if (!ssl_write_buffer_is_pending(ssl)) { /* Nothing is being written out, so the alert may be dispatched * immediately. */ return ssl->method->ssl_dispatch_alert(ssl); } /* else data is still being written out, we will get written some time in the * future */ return -1; } int ssl3_dispatch_alert(SSL *ssl) { ssl->s3->alert_dispatch = 0; int ret = do_ssl3_write(ssl, SSL3_RT_ALERT, &ssl->s3->send_alert[0], 2); if (ret <= 0) { ssl->s3->alert_dispatch = 1; return ret; } /* If the alert is fatal, flush the BIO now. */ if (ssl->s3->send_alert[0] == SSL3_AL_FATAL) { BIO_flush(ssl->wbio); } if (ssl->msg_callback != NULL) { ssl->msg_callback(1 /* write */, ssl->version, SSL3_RT_ALERT, ssl->s3->send_alert, 2, ssl, ssl->msg_callback_arg); } void (*cb)(const SSL *ssl, int type, int value) = NULL; if (ssl->info_callback != NULL) { cb = ssl->info_callback; } else if (ssl->ctx->info_callback != NULL) { cb = ssl->ctx->info_callback; } if (cb != NULL) { int alert = (ssl->s3->send_alert[0] << 8) | ssl->s3->send_alert[1]; cb(ssl, SSL_CB_WRITE_ALERT, alert); } return 1; }