diff options
author | Matt Caswell <matt@openssl.org> | 2015-02-01 19:47:15 +0300 |
---|---|---|
committer | Matt Caswell <matt@openssl.org> | 2015-03-26 16:58:51 +0300 |
commit | fe589e6175f350a3e83b39ea07a08b0c824ea6fb (patch) | |
tree | 5197733a594be01c1905ef638188df28403abf5e /ssl/s3_pkt.c | |
parent | 7604202070b3d3767fe75bc8c5a268ee8aedfb52 (diff) |
Move SSL3_RECORD oriented functions into ssl3_record.c
Reviewed-by: Richard Levitte <levitte@openssl.org>
Diffstat (limited to 'ssl/s3_pkt.c')
-rw-r--r-- | ssl/s3_pkt.c | 348 |
1 files changed, 0 insertions, 348 deletions
diff --git a/ssl/s3_pkt.c b/ssl/s3_pkt.c index 1ec76664be..6248043bec 100644 --- a/ssl/s3_pkt.c +++ b/ssl/s3_pkt.c @@ -134,7 +134,6 @@ static int do_ssl3_write(SSL *s, int type, const unsigned char *buf, unsigned int len, int create_empty_fragment); -static int ssl3_get_record(SSL *s); int ssl3_read_n(SSL *s, int n, int max, int extend) { @@ -285,353 +284,6 @@ int ssl3_read_n(SSL *s, int n, int max, int extend) return (n); } -/* - * MAX_EMPTY_RECORDS defines the number of consecutive, empty records that - * will be processed per call to ssl3_get_record. Without this limit an - * attacker could send empty records at a faster rate than we can process and - * cause ssl3_get_record to loop forever. - */ -#define MAX_EMPTY_RECORDS 32 - -/*- - * Call this to get a new input record. - * It will return <= 0 if more data is needed, normally due to an error - * or non-blocking IO. - * When it finishes, one packet has been decoded and can be found in - * ssl->s3->rrec.type - is the type of record - * ssl->s3->rrec.data, - data - * ssl->s3->rrec.length, - number of bytes - */ -/* used only by ssl3_read_bytes */ -static int ssl3_get_record(SSL *s) -{ - int ssl_major, ssl_minor, al; - int enc_err, n, i, ret = -1; - SSL3_RECORD *rr; - SSL_SESSION *sess; - unsigned char *p; - unsigned char md[EVP_MAX_MD_SIZE]; - short version; - unsigned mac_size; - size_t extra; - unsigned empty_record_count = 0; - - rr = RECORD_LAYER_get_rrec(&s->rlayer); - sess = s->session; - - if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER) - extra = SSL3_RT_MAX_EXTRA; - else - extra = 0; - if (extra && !s->s3->init_extra) { - /* - * An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER set after - * ssl3_setup_buffers() was done - */ - SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR); - return -1; - } - - again: - /* check if we have the header */ - if ((s->rstate != SSL_ST_READ_BODY) || - (s->packet_length < SSL3_RT_HEADER_LENGTH)) { - n = ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, - SSL3_BUFFER_get_len(RECORD_LAYER_get_rbuf(&s->rlayer)), 0); - if (n <= 0) - return (n); /* error or non-blocking */ - s->rstate = SSL_ST_READ_BODY; - - p = s->packet; - if (s->msg_callback) - s->msg_callback(0, 0, SSL3_RT_HEADER, p, 5, s, - s->msg_callback_arg); - - /* Pull apart the header into the SSL3_RECORD */ - rr->type = *(p++); - ssl_major = *(p++); - ssl_minor = *(p++); - version = (ssl_major << 8) | ssl_minor; - n2s(p, rr->length); - - /* Lets check version */ - if (!s->first_packet) { - if (version != s->version) { - SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_WRONG_VERSION_NUMBER); - if ((s->version & 0xFF00) == (version & 0xFF00) - && !s->enc_write_ctx && !s->write_hash) - /* - * Send back error using their minor version number :-) - */ - s->version = (unsigned short)version; - al = SSL_AD_PROTOCOL_VERSION; - goto f_err; - } - } - - if ((version >> 8) != SSL3_VERSION_MAJOR) { - SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_WRONG_VERSION_NUMBER); - goto err; - } - - if (rr->length > - SSL3_BUFFER_get_len(RECORD_LAYER_get_rbuf(&s->rlayer)) - - SSL3_RT_HEADER_LENGTH) { - al = SSL_AD_RECORD_OVERFLOW; - SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_PACKET_LENGTH_TOO_LONG); - goto f_err; - } - - /* now s->rstate == SSL_ST_READ_BODY */ - } - - /* s->rstate == SSL_ST_READ_BODY, get and decode the data */ - - if (rr->length > s->packet_length - SSL3_RT_HEADER_LENGTH) { - /* now s->packet_length == SSL3_RT_HEADER_LENGTH */ - i = rr->length; - n = ssl3_read_n(s, i, i, 1); - if (n <= 0) - return (n); /* error or non-blocking io */ - /* - * now n == rr->length, and s->packet_length == SSL3_RT_HEADER_LENGTH - * + rr->length - */ - } - - s->rstate = SSL_ST_READ_HEADER; /* set state for later operations */ - - /* - * At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length, - * and we have that many bytes in s->packet - */ - rr->input = &(s->packet[SSL3_RT_HEADER_LENGTH]); - - /* - * ok, we can now read from 's->packet' data into 'rr' rr->input points - * at rr->length bytes, which need to be copied into rr->data by either - * the decryption or by the decompression When the data is 'copied' into - * the rr->data buffer, rr->input will be pointed at the new buffer - */ - - /* - * We now have - encrypted [ MAC [ compressed [ plain ] ] ] rr->length - * bytes of encrypted compressed stuff. - */ - - /* check is not needed I believe */ - if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH + extra) { - al = SSL_AD_RECORD_OVERFLOW; - SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_ENCRYPTED_LENGTH_TOO_LONG); - goto f_err; - } - - /* decrypt in place in 'rr->input' */ - rr->data = rr->input; - rr->orig_len = rr->length; - /* - * If in encrypt-then-mac mode calculate mac from encrypted record. All - * the details below are public so no timing details can leak. - */ - if (SSL_USE_ETM(s) && s->read_hash) { - unsigned char *mac; - mac_size = EVP_MD_CTX_size(s->read_hash); - OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE); - if (rr->length < mac_size) { - al = SSL_AD_DECODE_ERROR; - SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_LENGTH_TOO_SHORT); - goto f_err; - } - rr->length -= mac_size; - mac = rr->data + rr->length; - i = s->method->ssl3_enc->mac(s, md, 0 /* not send */ ); - if (i < 0 || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0) { - al = SSL_AD_BAD_RECORD_MAC; - SSLerr(SSL_F_SSL3_GET_RECORD, - SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC); - goto f_err; - } - } - - enc_err = s->method->ssl3_enc->enc(s, 0); - /*- - * enc_err is: - * 0: (in non-constant time) if the record is publically invalid. - * 1: if the padding is valid - * -1: if the padding is invalid - */ - if (enc_err == 0) { - al = SSL_AD_DECRYPTION_FAILED; - SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_BLOCK_CIPHER_PAD_IS_WRONG); - goto f_err; - } -#ifdef TLS_DEBUG - printf("dec %d\n", rr->length); - { - unsigned int z; - for (z = 0; z < rr->length; z++) - printf("%02X%c", rr->data[z], ((z + 1) % 16) ? ' ' : '\n'); - } - printf("\n"); -#endif - - /* r->length is now the compressed data plus mac */ - if ((sess != NULL) && - (s->enc_read_ctx != NULL) && - (EVP_MD_CTX_md(s->read_hash) != NULL) && !SSL_USE_ETM(s)) { - /* s->read_hash != NULL => mac_size != -1 */ - unsigned char *mac = NULL; - unsigned char mac_tmp[EVP_MAX_MD_SIZE]; - mac_size = EVP_MD_CTX_size(s->read_hash); - OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE); - - /* - * orig_len is the length of the record before any padding was - * removed. This is public information, as is the MAC in use, - * therefore we can safely process the record in a different amount - * of time if it's too short to possibly contain a MAC. - */ - if (rr->orig_len < mac_size || - /* CBC records must have a padding length byte too. */ - (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE && - rr->orig_len < mac_size + 1)) { - al = SSL_AD_DECODE_ERROR; - SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_LENGTH_TOO_SHORT); - goto f_err; - } - - if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE) { - /* - * We update the length so that the TLS header bytes can be - * constructed correctly but we need to extract the MAC in - * constant time from within the record, without leaking the - * contents of the padding bytes. - */ - mac = mac_tmp; - ssl3_cbc_copy_mac(mac_tmp, rr, mac_size); - rr->length -= mac_size; - } else { - /* - * In this case there's no padding, so |rec->orig_len| equals - * |rec->length| and we checked that there's enough bytes for - * |mac_size| above. - */ - rr->length -= mac_size; - mac = &rr->data[rr->length]; - } - - i = s->method->ssl3_enc->mac(s, md, 0 /* not send */ ); - if (i < 0 || mac == NULL - || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0) - enc_err = -1; - if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + extra + mac_size) - enc_err = -1; - } - - if (enc_err < 0) { - /* - * A separate 'decryption_failed' alert was introduced with TLS 1.0, - * SSL 3.0 only has 'bad_record_mac'. But unless a decryption - * failure is directly visible from the ciphertext anyway, we should - * not reveal which kind of error occurred -- this might become - * visible to an attacker (e.g. via a logfile) - */ - al = SSL_AD_BAD_RECORD_MAC; - SSLerr(SSL_F_SSL3_GET_RECORD, - SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC); - goto f_err; - } - - /* r->length is now just compressed */ - if (s->expand != NULL) { - if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + extra) { - al = SSL_AD_RECORD_OVERFLOW; - SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_COMPRESSED_LENGTH_TOO_LONG); - goto f_err; - } - if (!ssl3_do_uncompress(s)) { - al = SSL_AD_DECOMPRESSION_FAILURE; - SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_BAD_DECOMPRESSION); - goto f_err; - } - } - - if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH + extra) { - al = SSL_AD_RECORD_OVERFLOW; - SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_DATA_LENGTH_TOO_LONG); - goto f_err; - } - - rr->off = 0; - /*- - * So at this point the following is true - * ssl->s3->rrec.type is the type of record - * ssl->s3->rrec.length == number of bytes in record - * ssl->s3->rrec.off == offset to first valid byte - * ssl->s3->rrec.data == where to take bytes from, increment - * after use :-). - */ - - /* we have pulled in a full packet so zero things */ - s->packet_length = 0; - - /* just read a 0 length packet */ - if (rr->length == 0) { - empty_record_count++; - if (empty_record_count > MAX_EMPTY_RECORDS) { - al = SSL_AD_UNEXPECTED_MESSAGE; - SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_RECORD_TOO_SMALL); - goto f_err; - } - goto again; - } - - return (1); - - f_err: - ssl3_send_alert(s, SSL3_AL_FATAL, al); - err: - return (ret); -} - -int ssl3_do_uncompress(SSL *ssl) -{ -#ifndef OPENSSL_NO_COMP - int i; - SSL3_RECORD *rr; - - rr = RECORD_LAYER_get_rrec(&ssl->rlayer); - i = COMP_expand_block(ssl->expand, rr->comp, - SSL3_RT_MAX_PLAIN_LENGTH, rr->data, - (int)rr->length); - if (i < 0) - return (0); - else - rr->length = i; - rr->data = rr->comp; -#endif - return (1); -} - -int ssl3_do_compress(SSL *ssl) -{ -#ifndef OPENSSL_NO_COMP - int i; - SSL3_RECORD *wr; - - wr = RECORD_LAYER_get_wrec(&ssl->rlayer); - i = COMP_compress_block(ssl->compress, wr->data, - SSL3_RT_MAX_COMPRESSED_LENGTH, - wr->input, (int)wr->length); - if (i < 0) - return (0); - else - wr->length = i; - - wr->input = wr->data; -#endif - return (1); -} /* * Call this to write data in records of type 'type' It will return <= 0 if |