From b8494591d1b1a143f3b192d845c238bbf3bc629d Mon Sep 17 00:00:00 2001 From: Kenny Root Date: Fri, 25 Sep 2015 02:29:14 +0000 Subject: Revert "Revert "external/boringssl: sync with upstream."" This reverts commit a04d78d392463df4e69a64360c952ffa5abd22f7. Underlying issue was fixed. Change-Id: I49685b653d16e728eb38e79e02b2c33ddeefed88 --- src/ssl/ssl_buffer.c | 318 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 318 insertions(+) create mode 100644 src/ssl/ssl_buffer.c (limited to 'src/ssl/ssl_buffer.c') diff --git a/src/ssl/ssl_buffer.c b/src/ssl/ssl_buffer.c new file mode 100644 index 0000000..63dcd80 --- /dev/null +++ b/src/ssl/ssl_buffer.c @@ -0,0 +1,318 @@ +/* Copyright (c) 2015, Google Inc. + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY + * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION + * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN + * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ + +#include + +#include +#include +#include +#include + +#include +#include +#include +#include + +#include "internal.h" + + +OPENSSL_COMPILE_ASSERT(0xffff <= INT_MAX, uint16_fits_in_int); + +OPENSSL_COMPILE_ASSERT((SSL3_ALIGN_PAYLOAD & (SSL3_ALIGN_PAYLOAD - 1)) == 0, + align_to_a_power_of_two); + +/* setup_buffer initializes |buf| with capacity |cap|, aligned such that data + * written after |header_len| is aligned to a |SSL3_ALIGN_PAYLOAD|-byte + * boundary. It returns one on success and zero on error. */ +static int setup_buffer(SSL3_BUFFER *buf, size_t header_len, size_t cap) { + if (buf->buf != NULL || cap > 0xffff) { + OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); + return 0; + } + + /* Add up to |SSL3_ALIGN_PAYLOAD| - 1 bytes of slack for alignment. */ + buf->buf = OPENSSL_malloc(cap + SSL3_ALIGN_PAYLOAD - 1); + if (buf->buf == NULL) { + OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); + return 0; + } + + /* Arrange the buffer such that the record body is aligned. */ + buf->offset = (0 - header_len - (uintptr_t)buf->buf) & + (SSL3_ALIGN_PAYLOAD - 1); + buf->len = 0; + buf->cap = cap; + return 1; +} + +static void consume_buffer(SSL3_BUFFER *buf, size_t len) { + if (len > buf->len) { + abort(); + } + buf->offset += (uint16_t)len; + buf->len -= (uint16_t)len; + buf->cap -= (uint16_t)len; +} + +static void clear_buffer(SSL3_BUFFER *buf) { + OPENSSL_free(buf->buf); + memset(buf, 0, sizeof(SSL3_BUFFER)); +} + +OPENSSL_COMPILE_ASSERT(DTLS1_RT_HEADER_LENGTH + SSL3_RT_MAX_ENCRYPTED_LENGTH + + SSL3_RT_MAX_EXTRA <= 0xffff, + maximum_read_buffer_too_large); + +/* setup_read_buffer initializes the read buffer if not already initialized. It + * returns one on success and zero on failure. */ +static int setup_read_buffer(SSL *ssl) { + SSL3_BUFFER *buf = &ssl->s3->read_buffer; + + if (buf->buf != NULL) { + return 1; + } + + size_t header_len = ssl_record_prefix_len(ssl); + size_t cap = SSL3_RT_MAX_ENCRYPTED_LENGTH; + if (SSL_IS_DTLS(ssl)) { + cap += DTLS1_RT_HEADER_LENGTH; + } else { + cap += SSL3_RT_HEADER_LENGTH; + } + if (ssl->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER) { + cap += SSL3_RT_MAX_EXTRA; + } + + return setup_buffer(buf, header_len, cap); +} + +uint8_t *ssl_read_buffer(SSL *ssl) { + return ssl->s3->read_buffer.buf + ssl->s3->read_buffer.offset; +} + +size_t ssl_read_buffer_len(const SSL *ssl) { + return ssl->s3->read_buffer.len; +} + +static int dtls_read_buffer_next_packet(SSL *ssl) { + SSL3_BUFFER *buf = &ssl->s3->read_buffer; + + if (buf->len > 0) { + /* It is an error to call |dtls_read_buffer_extend| when the read buffer is + * not empty. */ + OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); + return -1; + } + + /* Read a single packet from |ssl->rbio|. |buf->cap| must fit in an int. */ + ssl->rwstate = SSL_READING; + int ret = BIO_read(ssl->rbio, buf->buf + buf->offset, (int)buf->cap); + if (ret <= 0) { + return ret; + } + ssl->rwstate = SSL_NOTHING; + /* |BIO_read| was bound by |buf->cap|, so this cannot overflow. */ + buf->len = (uint16_t)ret; + return 1; +} + +static int tls_read_buffer_extend_to(SSL *ssl, size_t len) { + SSL3_BUFFER *buf = &ssl->s3->read_buffer; + + if (len > buf->cap) { + /* This may occur if |SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER| was toggled after + * |setup_read_buffer| was called. Stay within bounds, but do not attempt to + * recover. */ + OPENSSL_PUT_ERROR(SSL, SSL_R_BUFFER_TOO_SMALL); + return -1; + } + + /* Read until the target length is reached. */ + while (buf->len < len) { + /* The amount of data to read is bounded by |buf->cap|, which must fit in an + * int. */ + ssl->rwstate = SSL_READING; + int ret = BIO_read(ssl->rbio, buf->buf + buf->offset + buf->len, + (int)(len - buf->len)); + if (ret <= 0) { + return ret; + } + ssl->rwstate = SSL_NOTHING; + /* |BIO_read| was bound by |buf->cap - buf->len|, so this cannot + * overflow. */ + buf->len += (uint16_t)ret; + } + + return 1; +} + +int ssl_read_buffer_extend_to(SSL *ssl, size_t len) { + /* |ssl_read_buffer_extend_to| implicitly discards any consumed data. */ + ssl_read_buffer_discard(ssl); + + if (!setup_read_buffer(ssl)) { + return -1; + } + + if (ssl->rbio == NULL) { + OPENSSL_PUT_ERROR(SSL, SSL_R_BIO_NOT_SET); + return -1; + } + + ERR_clear_system_error(); + + int ret; + if (SSL_IS_DTLS(ssl)) { + /* |len| is ignored for a datagram transport. */ + ret = dtls_read_buffer_next_packet(ssl); + } else { + ret = tls_read_buffer_extend_to(ssl, len); + } + + if (ret <= 0) { + /* If the buffer was empty originally and remained empty after attempting to + * extend it, release the buffer until the next attempt. */ + ssl_read_buffer_discard(ssl); + } + return ret; +} + +void ssl_read_buffer_consume(SSL *ssl, size_t len) { + SSL3_BUFFER *buf = &ssl->s3->read_buffer; + + consume_buffer(buf, len); + if (!SSL_IS_DTLS(ssl)) { + /* The TLS stack never reads beyond the current record, so there will never + * be unconsumed data. If read-ahead is ever reimplemented, + * |ssl_read_buffer_discard| will require a |memcpy| to shift the excess + * back to the front of the buffer, to ensure there is enough space for the + * next record. */ + assert(buf->len == 0); + } +} + +void ssl_read_buffer_discard(SSL *ssl) { + if (ssl->s3->read_buffer.len == 0) { + ssl_read_buffer_clear(ssl); + } +} + +void ssl_read_buffer_clear(SSL *ssl) { + clear_buffer(&ssl->s3->read_buffer); +} + + +int ssl_write_buffer_is_pending(const SSL *ssl) { + return ssl->s3->write_buffer.len > 0; +} + +OPENSSL_COMPILE_ASSERT(SSL3_RT_HEADER_LENGTH * 2 + + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD * 2 + + SSL3_RT_MAX_PLAIN_LENGTH <= 0xffff, + maximum_tls_write_buffer_too_large); + +OPENSSL_COMPILE_ASSERT(DTLS1_RT_HEADER_LENGTH + + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD + + SSL3_RT_MAX_PLAIN_LENGTH <= 0xffff, + maximum_dtls_write_buffer_too_large); + +int ssl_write_buffer_init(SSL *ssl, uint8_t **out_ptr, size_t max_len) { + SSL3_BUFFER *buf = &ssl->s3->write_buffer; + + if (buf->buf != NULL) { + OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); + return 0; + } + + size_t header_len = ssl_seal_prefix_len(ssl); + + /* TODO(davidben): This matches the original behavior in keeping the malloc + * size consistent. Does this matter? |cap| could just be |max_len|. */ + size_t cap = SSL3_RT_MAX_PLAIN_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD; + if (SSL_IS_DTLS(ssl)) { + cap += DTLS1_RT_HEADER_LENGTH; + } else { + cap += SSL3_RT_HEADER_LENGTH; + if (ssl->mode & SSL_MODE_CBC_RECORD_SPLITTING) { + cap += SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD; + } + } + + if (max_len > cap) { + OPENSSL_PUT_ERROR(SSL, SSL_R_BUFFER_TOO_SMALL); + return 0; + } + + if (!setup_buffer(buf, header_len, cap)) { + return 0; + } + *out_ptr = buf->buf + buf->offset; + return 1; +} + +void ssl_write_buffer_set_len(SSL *ssl, size_t len) { + SSL3_BUFFER *buf = &ssl->s3->write_buffer; + + if (len > buf->cap) { + abort(); + } + buf->len = len; +} + +static int tls_write_buffer_flush(SSL *ssl) { + SSL3_BUFFER *buf = &ssl->s3->write_buffer; + + while (buf->len > 0) { + ssl->rwstate = SSL_WRITING; + int ret = BIO_write(ssl->wbio, buf->buf + buf->offset, buf->len); + if (ret <= 0) { + return ret; + } + ssl->rwstate = SSL_NOTHING; + consume_buffer(buf, (size_t)ret); + } + ssl_write_buffer_clear(ssl); + return 1; +} + +static int dtls_write_buffer_flush(SSL *ssl) { + SSL3_BUFFER *buf = &ssl->s3->write_buffer; + if (buf->len == 0) { + return 1; + } + + int ret = BIO_write(ssl->wbio, buf->buf + buf->offset, buf->len); + /* Drop the write buffer whether or not the write succeeded synchronously. + * TODO(davidben): How does this interact with the retry flag? */ + ssl_write_buffer_clear(ssl); + return (ret <= 0) ? ret : 1; +} + +int ssl_write_buffer_flush(SSL *ssl) { + if (ssl->wbio == NULL) { + OPENSSL_PUT_ERROR(SSL, SSL_R_BIO_NOT_SET); + return -1; + } + ERR_clear_system_error(); + + if (SSL_IS_DTLS(ssl)) { + return dtls_write_buffer_flush(ssl); + } else { + return tls_write_buffer_flush(ssl); + } +} + +void ssl_write_buffer_clear(SSL *ssl) { + clear_buffer(&ssl->s3->write_buffer); +} -- cgit v1.1