*/
#include "../ssl_locl.h"
+#include "internal/constant_time_locl.h"
+#include <openssl/rand.h>
+#include "record_locl.h"
+
+static const unsigned char ssl3_pad_1[48] = {
+ 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36,
+ 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36,
+ 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36,
+ 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36,
+ 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36,
+ 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36
+};
+
+static const unsigned char ssl3_pad_2[48] = {
+ 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c,
+ 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c,
+ 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c,
+ 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c,
+ 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c,
+ 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c
+};
+/*
+ * Clear the contents of an SSL3_RECORD but retain any memory allocated
+ */
void SSL3_RECORD_clear(SSL3_RECORD *r)
{
- memset(r->seq_num, 0, sizeof(r->seq_num));
+ unsigned char *comp = r->comp;
+
+ memset(r, 0, sizeof(*r));
+ r->comp = comp;
}
void SSL3_RECORD_release(SSL3_RECORD *r)
{
- if (r->comp != NULL)
- OPENSSL_free(r->comp);
+ OPENSSL_free(r->comp);
r->comp = NULL;
}
-int SSL3_RECORD_setup(SSL3_RECORD *r, size_t len)
+int SSL3_RECORD_setup(SSL3_RECORD *r)
{
if (r->comp == NULL)
- r->comp = (unsigned char *) OPENSSL_malloc(len);
+ r->comp = (unsigned char *)
+ OPENSSL_malloc(SSL3_RT_MAX_ENCRYPTED_LENGTH);
if (r->comp == NULL)
return 0;
return 1;
void SSL3_RECORD_set_seq_num(SSL3_RECORD *r, const unsigned char *seq_num)
{
- memcpy(r->seq_num, seq_num, 8);
+ memcpy(r->seq_num, seq_num, SEQ_NUM_SIZE);
}
/*
*/
#define MAX_EMPTY_RECORDS 32
+#define SSL2_RT_HEADER_LENGTH 2
/*-
* Call this to get a new input record.
* It will return <= 0 if more data is needed, normally due to an error
again:
/* check if we have the header */
- if ((s->rstate != SSL_ST_READ_BODY) ||
- (s->packet_length < SSL3_RT_HEADER_LENGTH)) {
+ if ((RECORD_LAYER_get_rstate(&s->rlayer) != SSL_ST_READ_BODY) ||
+ (RECORD_LAYER_get_packet_length(&s->rlayer) < SSL3_RT_HEADER_LENGTH)) {
n = ssl3_read_n(s, SSL3_RT_HEADER_LENGTH,
- SSL3_BUFFER_get_len(RECORD_LAYER_get_rbuf(&s->rlayer)), 0);
+ SSL3_BUFFER_get_len(&s->rlayer.rbuf), 0);
if (n <= 0)
return (n); /* error or non-blocking */
- s->rstate = SSL_ST_READ_BODY;
+ RECORD_LAYER_set_rstate(&s->rlayer, 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);
+ p = RECORD_LAYER_get_packet(&s->rlayer);
- /* 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);
+ /*
+ * Check whether this is a regular record or an SSLv2 style record. The
+ * latter is only used in an initial ClientHello for old clients. We
+ * check s->read_hash and s->enc_read_ctx to ensure this does not apply
+ * during renegotiation
+ */
+ if (s->first_packet && s->server && !s->read_hash && !s->enc_read_ctx
+ && (p[0] & 0x80) && (p[2] == SSL2_MT_CLIENT_HELLO)) {
+ /* SSLv2 style record */
+ rr->type = SSL3_RT_HANDSHAKE;
+ rr->rec_version = SSL2_VERSION;
+
+ rr->length = ((p[0] & 0x7f) << 8) | p[1];
+
+ if (rr->length > SSL3_BUFFER_get_len(&s->rlayer.rbuf)
+ - SSL2_RT_HEADER_LENGTH) {
+ al = SSL_AD_RECORD_OVERFLOW;
+ SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_PACKET_LENGTH_TOO_LONG);
+ goto f_err;
+ }
- /* Lets check version */
- if (!s->first_packet) {
- if (version != s->version) {
+ if (rr->length < MIN_SSL2_RECORD_LEN) {
+ al = SSL_AD_HANDSHAKE_FAILURE;
+ SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_LENGTH_TOO_SHORT);
+ goto f_err;
+ }
+ } else {
+ /* SSLv3+ style record */
+ 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;
+ rr->rec_version = version;
+ n2s(p, rr->length);
+
+ /* Lets check version */
+ if (!s->first_packet && 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)
+ && !s->enc_write_ctx && !s->write_hash) {
+ if (rr->type == SSL3_RT_ALERT) {
+ /*
+ * The record is using an incorrect version number, but
+ * what we've got appears to be an alert. We haven't
+ * read the body yet to check whether its a fatal or
+ * not - but chances are it is. We probably shouldn't
+ * send a fatal alert back. We'll just end.
+ */
+ goto err;
+ }
/*
* 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 ((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;
+ if (rr->length >
+ SSL3_BUFFER_get_len(&s->rlayer.rbuf)
+ - 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 */
+ /* now s->rlayer.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 */
+ /*
+ * s->rlayer.rstate == SSL_ST_READ_BODY, get and decode the data.
+ * Calculate how much more data we need to read for the rest of the record
+ */
+ if (rr->rec_version == SSL2_VERSION) {
+ i = rr->length + SSL2_RT_HEADER_LENGTH - SSL3_RT_HEADER_LENGTH;
+ } else {
i = rr->length;
+ }
+ if (i > 0) {
+ /* now s->packet_length == SSL3_RT_HEADER_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 */
+ /* set state for later operations */
+ RECORD_LAYER_set_rstate(&s->rlayer, SSL_ST_READ_HEADER);
/*
- * At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
+ * At this point, s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length,
+ * or s->packet_length == SSL2_RT_HEADER_LENGTH + rr->length
* and we have that many bytes in s->packet
*/
- rr->input = &(s->packet[SSL3_RT_HEADER_LENGTH]);
+ if(rr->rec_version == SSL2_VERSION) {
+ rr->input = &(RECORD_LAYER_get_packet(&s->rlayer)[SSL2_RT_HEADER_LENGTH]);
+ } else {
+ rr->input = &(RECORD_LAYER_get_packet(&s->rlayer)[SSL3_RT_HEADER_LENGTH]);
+ }
/*
* ok, we can now read from 's->packet' data into 'rr' rr->input points
*/
/* we have pulled in a full packet so zero things */
- s->packet_length = 0;
+ RECORD_LAYER_reset_packet_length(&s->rlayer);
/* just read a 0 length packet */
if (rr->length == 0) {
return (1);
}
+/*-
+ * ssl3_enc encrypts/decrypts the record in |s->wrec| / |s->rrec|, respectively.
+ *
+ * Returns:
+ * 0: (in non-constant time) if the record is publically invalid (i.e. too
+ * short etc).
+ * 1: if the record's padding is valid / the encryption was successful.
+ * -1: if the record's padding is invalid or, if sending, an internal error
+ * occurred.
+ */
+int ssl3_enc(SSL *s, int send)
+{
+ SSL3_RECORD *rec;
+ EVP_CIPHER_CTX *ds;
+ unsigned long l;
+ int bs, i, mac_size = 0;
+ const EVP_CIPHER *enc;
+
+ if (send) {
+ ds = s->enc_write_ctx;
+ rec = RECORD_LAYER_get_wrec(&s->rlayer);
+ if (s->enc_write_ctx == NULL)
+ enc = NULL;
+ else
+ enc = EVP_CIPHER_CTX_cipher(s->enc_write_ctx);
+ } else {
+ ds = s->enc_read_ctx;
+ rec = RECORD_LAYER_get_rrec(&s->rlayer);
+ if (s->enc_read_ctx == NULL)
+ enc = NULL;
+ else
+ enc = EVP_CIPHER_CTX_cipher(s->enc_read_ctx);
+ }
+
+ if ((s->session == NULL) || (ds == NULL) || (enc == NULL)) {
+ memmove(rec->data, rec->input, rec->length);
+ rec->input = rec->data;
+ } else {
+ l = rec->length;
+ bs = EVP_CIPHER_block_size(ds->cipher);
+
+ /* COMPRESS */
+
+ if ((bs != 1) && send) {
+ i = bs - ((int)l % bs);
+
+ /* we need to add 'i-1' padding bytes */
+ l += i;
+ /*
+ * the last of these zero bytes will be overwritten with the
+ * padding length.
+ */
+ memset(&rec->input[rec->length], 0, i);
+ rec->length += i;
+ rec->input[l - 1] = (i - 1);
+ }
+
+ if (!send) {
+ if (l == 0 || l % bs != 0)
+ return 0;
+ /* otherwise, rec->length >= bs */
+ }
+
+ if (EVP_Cipher(ds, rec->data, rec->input, l) < 1)
+ return -1;
+
+ if (EVP_MD_CTX_md(s->read_hash) != NULL)
+ mac_size = EVP_MD_CTX_size(s->read_hash);
+ if ((bs != 1) && !send)
+ return ssl3_cbc_remove_padding(s, rec, bs, mac_size);
+ }
+ return (1);
+}
+
+/*-
+ * tls1_enc encrypts/decrypts the record in |s->wrec| / |s->rrec|, respectively.
+ *
+ * Returns:
+ * 0: (in non-constant time) if the record is publically invalid (i.e. too
+ * short etc).
+ * 1: if the record's padding is valid / the encryption was successful.
+ * -1: if the record's padding/AEAD-authenticator is invalid or, if sending,
+ * an internal error occurred.
+ */
+int tls1_enc(SSL *s, int send)
+{
+ SSL3_RECORD *rec;
+ EVP_CIPHER_CTX *ds;
+ unsigned long l;
+ int bs, i, j, k, pad = 0, ret, mac_size = 0;
+ const EVP_CIPHER *enc;
+
+ if (send) {
+ if (EVP_MD_CTX_md(s->write_hash)) {
+ int n = EVP_MD_CTX_size(s->write_hash);
+ OPENSSL_assert(n >= 0);
+ }
+ ds = s->enc_write_ctx;
+ rec = RECORD_LAYER_get_wrec(&s->rlayer);
+ if (s->enc_write_ctx == NULL)
+ enc = NULL;
+ else {
+ int ivlen;
+ enc = EVP_CIPHER_CTX_cipher(s->enc_write_ctx);
+ /* For TLSv1.1 and later explicit IV */
+ if (SSL_USE_EXPLICIT_IV(s)
+ && EVP_CIPHER_mode(enc) == EVP_CIPH_CBC_MODE)
+ ivlen = EVP_CIPHER_iv_length(enc);
+ else
+ ivlen = 0;
+ if (ivlen > 1) {
+ if (rec->data != rec->input)
+ /*
+ * we can't write into the input stream: Can this ever
+ * happen?? (steve)
+ */
+ fprintf(stderr,
+ "%s:%d: rec->data != rec->input\n",
+ __FILE__, __LINE__);
+ else if (RAND_bytes(rec->input, ivlen) <= 0)
+ return -1;
+ }
+ }
+ } else {
+ if (EVP_MD_CTX_md(s->read_hash)) {
+ int n = EVP_MD_CTX_size(s->read_hash);
+ OPENSSL_assert(n >= 0);
+ }
+ ds = s->enc_read_ctx;
+ rec = RECORD_LAYER_get_rrec(&s->rlayer);
+ if (s->enc_read_ctx == NULL)
+ enc = NULL;
+ else
+ enc = EVP_CIPHER_CTX_cipher(s->enc_read_ctx);
+ }
+
+ if ((s->session == NULL) || (ds == NULL) || (enc == NULL)) {
+ memmove(rec->data, rec->input, rec->length);
+ rec->input = rec->data;
+ ret = 1;
+ } else {
+ l = rec->length;
+ bs = EVP_CIPHER_block_size(ds->cipher);
+
+ if (EVP_CIPHER_flags(ds->cipher) & EVP_CIPH_FLAG_AEAD_CIPHER) {
+ unsigned char buf[EVP_AEAD_TLS1_AAD_LEN], *seq;
+
+ seq = send ? RECORD_LAYER_get_write_sequence(&s->rlayer)
+ : RECORD_LAYER_get_read_sequence(&s->rlayer);
+
+ if (SSL_IS_DTLS(s)) {
+ unsigned char dtlsseq[9], *p = dtlsseq;
+
+ s2n(send ? DTLS_RECORD_LAYER_get_w_epoch(&s->rlayer) :
+ DTLS_RECORD_LAYER_get_r_epoch(&s->rlayer), p);
+ memcpy(p, &seq[2], 6);
+ memcpy(buf, dtlsseq, 8);
+ } else {
+ memcpy(buf, seq, 8);
+ for (i = 7; i >= 0; i--) { /* increment */
+ ++seq[i];
+ if (seq[i] != 0)
+ break;
+ }
+ }
+
+ buf[8] = rec->type;
+ buf[9] = (unsigned char)(s->version >> 8);
+ buf[10] = (unsigned char)(s->version);
+ buf[11] = rec->length >> 8;
+ buf[12] = rec->length & 0xff;
+ pad = EVP_CIPHER_CTX_ctrl(ds, EVP_CTRL_AEAD_TLS1_AAD,
+ EVP_AEAD_TLS1_AAD_LEN, buf);
+ if (pad <= 0)
+ return -1;
+ if (send) {
+ l += pad;
+ rec->length += pad;
+ }
+ } else if ((bs != 1) && send) {
+ i = bs - ((int)l % bs);
+
+ /* Add weird padding of upto 256 bytes */
+
+ /* we need to add 'i' padding bytes of value j */
+ j = i - 1;
+ for (k = (int)l; k < (int)(l + i); k++)
+ rec->input[k] = j;
+ l += i;
+ rec->length += i;
+ }
+
+ if (!send) {
+ if (l == 0 || l % bs != 0)
+ return 0;
+ }
+
+ i = EVP_Cipher(ds, rec->data, rec->input, l);
+ if ((EVP_CIPHER_flags(ds->cipher) & EVP_CIPH_FLAG_CUSTOM_CIPHER)
+ ? (i < 0)
+ : (i == 0))
+ return -1; /* AEAD can fail to verify MAC */
+ if (send == 0) {
+ if (EVP_CIPHER_mode(enc) == EVP_CIPH_GCM_MODE) {
+ rec->data += EVP_GCM_TLS_EXPLICIT_IV_LEN;
+ rec->input += EVP_GCM_TLS_EXPLICIT_IV_LEN;
+ rec->length -= EVP_GCM_TLS_EXPLICIT_IV_LEN;
+ } else if (EVP_CIPHER_mode(enc) == EVP_CIPH_CCM_MODE) {
+ rec->data += EVP_CCM_TLS_EXPLICIT_IV_LEN;
+ rec->input += EVP_CCM_TLS_EXPLICIT_IV_LEN;
+ rec->length -= EVP_CCM_TLS_EXPLICIT_IV_LEN;
+ }
+ }
+
+ ret = 1;
+ if (!SSL_USE_ETM(s) && EVP_MD_CTX_md(s->read_hash) != NULL)
+ mac_size = EVP_MD_CTX_size(s->read_hash);
+ if ((bs != 1) && !send)
+ ret = tls1_cbc_remove_padding(s, rec, bs, mac_size);
+ if (pad && !send)
+ rec->length -= pad;
+ }
+ return ret;
+}
+
+int n_ssl3_mac(SSL *ssl, unsigned char *md, int send)
+{
+ SSL3_RECORD *rec;
+ unsigned char *mac_sec, *seq;
+ const EVP_MD_CTX *hash;
+ unsigned char *p, rec_char;
+ size_t md_size;
+ int npad;
+ int t;
+
+ if (send) {
+ rec = RECORD_LAYER_get_wrec(&ssl->rlayer);
+ mac_sec = &(ssl->s3->write_mac_secret[0]);
+ seq = RECORD_LAYER_get_write_sequence(&ssl->rlayer);
+ hash = ssl->write_hash;
+ } else {
+ rec = RECORD_LAYER_get_rrec(&ssl->rlayer);
+ mac_sec = &(ssl->s3->read_mac_secret[0]);
+ seq = RECORD_LAYER_get_read_sequence(&ssl->rlayer);
+ hash = ssl->read_hash;
+ }
+
+ t = EVP_MD_CTX_size(hash);
+ if (t < 0)
+ return -1;
+ md_size = t;
+ npad = (48 / md_size) * md_size;
+
+ if (!send &&
+ EVP_CIPHER_CTX_mode(ssl->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
+ ssl3_cbc_record_digest_supported(hash)) {
+ /*
+ * This is a CBC-encrypted record. We must avoid leaking any
+ * timing-side channel information about how many blocks of data we
+ * are hashing because that gives an attacker a timing-oracle.
+ */
+
+ /*-
+ * npad is, at most, 48 bytes and that's with MD5:
+ * 16 + 48 + 8 (sequence bytes) + 1 + 2 = 75.
+ *
+ * With SHA-1 (the largest hash speced for SSLv3) the hash size
+ * goes up 4, but npad goes down by 8, resulting in a smaller
+ * total size.
+ */
+ unsigned char header[75];
+ unsigned j = 0;
+ memcpy(header + j, mac_sec, md_size);
+ j += md_size;
+ memcpy(header + j, ssl3_pad_1, npad);
+ j += npad;
+ memcpy(header + j, seq, 8);
+ j += 8;
+ header[j++] = rec->type;
+ header[j++] = rec->length >> 8;
+ header[j++] = rec->length & 0xff;
+
+ /* Final param == is SSLv3 */
+ if (ssl3_cbc_digest_record(hash,
+ md, &md_size,
+ header, rec->input,
+ rec->length + md_size, rec->orig_len,
+ mac_sec, md_size, 1) <= 0)
+ return -1;
+ } else {
+ unsigned int md_size_u;
+ /* Chop the digest off the end :-) */
+ EVP_MD_CTX *md_ctx = EVP_MD_CTX_create();
+
+ if (md_ctx == NULL)
+ return -1;
+
+ rec_char = rec->type;
+ p = md;
+ s2n(rec->length, p);
+ if (EVP_MD_CTX_copy_ex(md_ctx, hash) <= 0
+ || EVP_DigestUpdate(md_ctx, mac_sec, md_size) <= 0
+ || EVP_DigestUpdate(md_ctx, ssl3_pad_1, npad) <= 0
+ || EVP_DigestUpdate(md_ctx, seq, 8) <= 0
+ || EVP_DigestUpdate(md_ctx, &rec_char, 1) <= 0
+ || EVP_DigestUpdate(md_ctx, md, 2) <= 0
+ || EVP_DigestUpdate(md_ctx, rec->input, rec->length) <= 0
+ || EVP_DigestFinal_ex(md_ctx, md, NULL) <= 0
+ || EVP_MD_CTX_copy_ex(md_ctx, hash) <= 0
+ || EVP_DigestUpdate(md_ctx, mac_sec, md_size) <= 0
+ || EVP_DigestUpdate(md_ctx, ssl3_pad_2, npad) <= 0
+ || EVP_DigestUpdate(md_ctx, md, md_size) <= 0
+ || EVP_DigestFinal_ex(md_ctx, md, &md_size_u) <= 0) {
+ EVP_MD_CTX_init(md_ctx);
+ return -1;
+ }
+ md_size = md_size_u;
+
+ EVP_MD_CTX_destroy(md_ctx);
+ }
+
+ ssl3_record_sequence_update(seq);
+ return (md_size);
+}
+
+int tls1_mac(SSL *ssl, unsigned char *md, int send)
+{
+ SSL3_RECORD *rec;
+ unsigned char *seq;
+ EVP_MD_CTX *hash;
+ size_t md_size;
+ int i;
+ EVP_MD_CTX *hmac = NULL, *mac_ctx;
+ unsigned char header[13];
+ int stream_mac = (send ? (ssl->mac_flags & SSL_MAC_FLAG_WRITE_MAC_STREAM)
+ : (ssl->mac_flags & SSL_MAC_FLAG_READ_MAC_STREAM));
+ int t;
+
+ if (send) {
+ rec = RECORD_LAYER_get_wrec(&ssl->rlayer);
+ seq = RECORD_LAYER_get_write_sequence(&ssl->rlayer);
+ hash = ssl->write_hash;
+ } else {
+ rec = RECORD_LAYER_get_rrec(&ssl->rlayer);
+ seq = RECORD_LAYER_get_read_sequence(&ssl->rlayer);
+ hash = ssl->read_hash;
+ }
+
+ t = EVP_MD_CTX_size(hash);
+ OPENSSL_assert(t >= 0);
+ md_size = t;
+
+ /* I should fix this up TLS TLS TLS TLS TLS XXXXXXXX */
+ if (stream_mac) {
+ mac_ctx = hash;
+ } else {
+ hmac = EVP_MD_CTX_create();
+ if (hmac == NULL
+ || !EVP_MD_CTX_copy(hmac, hash))
+ return -1;
+ mac_ctx = hmac;
+ }
+
+ if (SSL_IS_DTLS(ssl)) {
+ unsigned char dtlsseq[8], *p = dtlsseq;
+
+ s2n(send ? DTLS_RECORD_LAYER_get_w_epoch(&ssl->rlayer) :
+ DTLS_RECORD_LAYER_get_r_epoch(&ssl->rlayer), p);
+ memcpy(p, &seq[2], 6);
+
+ memcpy(header, dtlsseq, 8);
+ } else
+ memcpy(header, seq, 8);
+
+ header[8] = rec->type;
+ header[9] = (unsigned char)(ssl->version >> 8);
+ header[10] = (unsigned char)(ssl->version);
+ header[11] = (rec->length) >> 8;
+ header[12] = (rec->length) & 0xff;
+
+ if (!send && !SSL_USE_ETM(ssl) &&
+ EVP_CIPHER_CTX_mode(ssl->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
+ ssl3_cbc_record_digest_supported(mac_ctx)) {
+ /*
+ * This is a CBC-encrypted record. We must avoid leaking any
+ * timing-side channel information about how many blocks of data we
+ * are hashing because that gives an attacker a timing-oracle.
+ */
+ /* Final param == not SSLv3 */
+ if (ssl3_cbc_digest_record(mac_ctx,
+ md, &md_size,
+ header, rec->input,
+ rec->length + md_size, rec->orig_len,
+ ssl->s3->read_mac_secret,
+ ssl->s3->read_mac_secret_size, 0) <= 0) {
+ EVP_MD_CTX_destroy(hmac);
+ return -1;
+ }
+ } else {
+ if (EVP_DigestSignUpdate(mac_ctx, header, sizeof(header)) <= 0
+ || EVP_DigestSignUpdate(mac_ctx, rec->input, rec->length) <= 0
+ || EVP_DigestSignFinal(mac_ctx, md, &md_size) <= 0) {
+ EVP_MD_CTX_destroy(hmac);
+ return -1;
+ }
+ if (!send && !SSL_USE_ETM(ssl) && FIPS_mode())
+ tls_fips_digest_extra(ssl->enc_read_ctx,
+ mac_ctx, rec->input,
+ rec->length, rec->orig_len);
+ }
+
+ EVP_MD_CTX_destroy(hmac);
+
+#ifdef TLS_DEBUG
+ fprintf(stderr, "seq=");
+ {
+ int z;
+ for (z = 0; z < 8; z++)
+ fprintf(stderr, "%02X ", seq[z]);
+ fprintf(stderr, "\n");
+ }
+ fprintf(stderr, "rec=");
+ {
+ unsigned int z;
+ for (z = 0; z < rec->length; z++)
+ fprintf(stderr, "%02X ", rec->data[z]);
+ fprintf(stderr, "\n");
+ }
+#endif
+
+ if (!SSL_IS_DTLS(ssl)) {
+ for (i = 7; i >= 0; i--) {
+ ++seq[i];
+ if (seq[i] != 0)
+ break;
+ }
+ }
+#ifdef TLS_DEBUG
+ {
+ unsigned int z;
+ for (z = 0; z < md_size; z++)
+ fprintf(stderr, "%02X ", md[z]);
+ fprintf(stderr, "\n");
+ }
+#endif
+ return (md_size);
+}
+
+/*-
+ * ssl3_cbc_remove_padding removes padding from the decrypted, SSLv3, CBC
+ * record in |rec| by updating |rec->length| in constant time.
+ *
+ * block_size: the block size of the cipher used to encrypt the record.
+ * returns:
+ * 0: (in non-constant time) if the record is publicly invalid.
+ * 1: if the padding was valid
+ * -1: otherwise.
+ */
+int ssl3_cbc_remove_padding(const SSL *s,
+ SSL3_RECORD *rec,
+ unsigned block_size, unsigned mac_size)
+{
+ unsigned padding_length, good;
+ const unsigned overhead = 1 /* padding length byte */ + mac_size;
+
+ /*
+ * These lengths are all public so we can test them in non-constant time.
+ */
+ if (overhead > rec->length)
+ return 0;
+
+ padding_length = rec->data[rec->length - 1];
+ good = constant_time_ge(rec->length, padding_length + overhead);
+ /* SSLv3 requires that the padding is minimal. */
+ good &= constant_time_ge(block_size, padding_length + 1);
+ rec->length -= good & (padding_length + 1);
+ return constant_time_select_int(good, 1, -1);
+}
+
+/*-
+ * tls1_cbc_remove_padding removes the CBC padding from the decrypted, TLS, CBC
+ * record in |rec| in constant time and returns 1 if the padding is valid and
+ * -1 otherwise. It also removes any explicit IV from the start of the record
+ * without leaking any timing about whether there was enough space after the
+ * padding was removed.
+ *
+ * block_size: the block size of the cipher used to encrypt the record.
+ * returns:
+ * 0: (in non-constant time) if the record is publicly invalid.
+ * 1: if the padding was valid
+ * -1: otherwise.
+ */
+int tls1_cbc_remove_padding(const SSL *s,
+ SSL3_RECORD *rec,
+ unsigned block_size, unsigned mac_size)
+{
+ unsigned padding_length, good, to_check, i;
+ const unsigned overhead = 1 /* padding length byte */ + mac_size;
+ /* Check if version requires explicit IV */
+ if (SSL_USE_EXPLICIT_IV(s)) {
+ /*
+ * These lengths are all public so we can test them in non-constant
+ * time.
+ */
+ if (overhead + block_size > rec->length)
+ return 0;
+ /* We can now safely skip explicit IV */
+ rec->data += block_size;
+ rec->input += block_size;
+ rec->length -= block_size;
+ rec->orig_len -= block_size;
+ } else if (overhead > rec->length)
+ return 0;
+
+ padding_length = rec->data[rec->length - 1];
+
+ if (EVP_CIPHER_flags(s->enc_read_ctx->cipher) & EVP_CIPH_FLAG_AEAD_CIPHER) {
+ /* padding is already verified */
+ rec->length -= padding_length + 1;
+ return 1;
+ }
+
+ good = constant_time_ge(rec->length, overhead + padding_length);
+ /*
+ * The padding consists of a length byte at the end of the record and
+ * then that many bytes of padding, all with the same value as the length
+ * byte. Thus, with the length byte included, there are i+1 bytes of
+ * padding. We can't check just |padding_length+1| bytes because that
+ * leaks decrypted information. Therefore we always have to check the
+ * maximum amount of padding possible. (Again, the length of the record
+ * is public information so we can use it.)
+ */
+ to_check = 255; /* maximum amount of padding. */
+ if (to_check > rec->length - 1)
+ to_check = rec->length - 1;
+
+ for (i = 0; i < to_check; i++) {
+ unsigned char mask = constant_time_ge_8(padding_length, i);
+ unsigned char b = rec->data[rec->length - 1 - i];
+ /*
+ * The final |padding_length+1| bytes should all have the value
+ * |padding_length|. Therefore the XOR should be zero.
+ */
+ good &= ~(mask & (padding_length ^ b));
+ }
+
+ /*
+ * If any of the final |padding_length+1| bytes had the wrong value, one
+ * or more of the lower eight bits of |good| will be cleared.
+ */
+ good = constant_time_eq(0xff, good & 0xff);
+ rec->length -= good & (padding_length + 1);
+
+ return constant_time_select_int(good, 1, -1);
+}
+
+/*-
+ * ssl3_cbc_copy_mac copies |md_size| bytes from the end of |rec| to |out| in
+ * constant time (independent of the concrete value of rec->length, which may
+ * vary within a 256-byte window).
+ *
+ * ssl3_cbc_remove_padding or tls1_cbc_remove_padding must be called prior to
+ * this function.
+ *
+ * On entry:
+ * rec->orig_len >= md_size
+ * md_size <= EVP_MAX_MD_SIZE
+ *
+ * If CBC_MAC_ROTATE_IN_PLACE is defined then the rotation is performed with
+ * variable accesses in a 64-byte-aligned buffer. Assuming that this fits into
+ * a single or pair of cache-lines, then the variable memory accesses don't
+ * actually affect the timing. CPUs with smaller cache-lines [if any] are
+ * not multi-core and are not considered vulnerable to cache-timing attacks.
+ */
+#define CBC_MAC_ROTATE_IN_PLACE
+
+void ssl3_cbc_copy_mac(unsigned char *out,
+ const SSL3_RECORD *rec, unsigned md_size)
+{
+#if defined(CBC_MAC_ROTATE_IN_PLACE)
+ unsigned char rotated_mac_buf[64 + EVP_MAX_MD_SIZE];
+ unsigned char *rotated_mac;
+#else
+ unsigned char rotated_mac[EVP_MAX_MD_SIZE];
+#endif
+
+ /*
+ * mac_end is the index of |rec->data| just after the end of the MAC.
+ */
+ unsigned mac_end = rec->length;
+ unsigned mac_start = mac_end - md_size;
+ /*
+ * scan_start contains the number of bytes that we can ignore because the
+ * MAC's position can only vary by 255 bytes.
+ */
+ unsigned scan_start = 0;
+ unsigned i, j;
+ unsigned div_spoiler;
+ unsigned rotate_offset;
+
+ OPENSSL_assert(rec->orig_len >= md_size);
+ OPENSSL_assert(md_size <= EVP_MAX_MD_SIZE);
+
+#if defined(CBC_MAC_ROTATE_IN_PLACE)
+ rotated_mac = rotated_mac_buf + ((0 - (size_t)rotated_mac_buf) & 63);
+#endif
+
+ /* This information is public so it's safe to branch based on it. */
+ if (rec->orig_len > md_size + 255 + 1)
+ scan_start = rec->orig_len - (md_size + 255 + 1);
+ /*
+ * div_spoiler contains a multiple of md_size that is used to cause the
+ * modulo operation to be constant time. Without this, the time varies
+ * based on the amount of padding when running on Intel chips at least.
+ * The aim of right-shifting md_size is so that the compiler doesn't
+ * figure out that it can remove div_spoiler as that would require it to
+ * prove that md_size is always even, which I hope is beyond it.
+ */
+ div_spoiler = md_size >> 1;
+ div_spoiler <<= (sizeof(div_spoiler) - 1) * 8;
+ rotate_offset = (div_spoiler + mac_start - scan_start) % md_size;
+
+ memset(rotated_mac, 0, md_size);
+ for (i = scan_start, j = 0; i < rec->orig_len; i++) {
+ unsigned char mac_started = constant_time_ge_8(i, mac_start);
+ unsigned char mac_ended = constant_time_ge_8(i, mac_end);
+ unsigned char b = rec->data[i];
+ rotated_mac[j++] |= b & mac_started & ~mac_ended;
+ j &= constant_time_lt(j, md_size);
+ }
+
+ /* Now rotate the MAC */
+#if defined(CBC_MAC_ROTATE_IN_PLACE)
+ j = 0;
+ for (i = 0; i < md_size; i++) {
+ /* in case cache-line is 32 bytes, touch second line */
+ ((volatile unsigned char *)rotated_mac)[rotate_offset ^ 32];
+ out[j++] = rotated_mac[rotate_offset++];
+ rotate_offset &= constant_time_lt(rotate_offset, md_size);
+ }
+#else
+ memset(out, 0, md_size);
+ rotate_offset = md_size - rotate_offset;
+ rotate_offset &= constant_time_lt(rotate_offset, md_size);
+ for (i = 0; i < md_size; i++) {
+ for (j = 0; j < md_size; j++)
+ out[j] |= rotated_mac[i] & constant_time_eq_8(j, rotate_offset);
+ rotate_offset++;
+ rotate_offset &= constant_time_lt(rotate_offset, md_size);
+ }
+#endif
+}
+
int dtls1_process_record(SSL *s)
{
int i, al;
* 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[DTLS1_RT_HEADER_LENGTH]);
+ rr->input = &(RECORD_LAYER_get_packet(&s->rlayer)[DTLS1_RT_HEADER_LENGTH]);
/*
* ok, we can now read from 's->packet' data into 'rr' rr->input points
if (enc_err == 0) {
/* For DTLS we simply ignore bad packets. */
rr->length = 0;
- s->packet_length = 0;
+ RECORD_LAYER_reset_packet_length(&s->rlayer);
goto err;
}
#ifdef TLS_DEBUG
if (enc_err < 0) {
/* decryption failed, silently discard message */
rr->length = 0;
- s->packet_length = 0;
+ RECORD_LAYER_reset_packet_length(&s->rlayer);
goto err;
}
*/
/* we have pulled in a full packet so zero things */
- s->packet_length = 0;
+ RECORD_LAYER_reset_packet_length(&s->rlayer);
return (1);
f_err:
*/
#define dtls1_get_processed_record(s) \
dtls1_retrieve_buffered_record((s), \
- &((s)->d1->processed_rcds))
+ &(DTLS_RECORD_LAYER_get_processed_rcds(&s->rlayer)))
/*-
* Call this to get a new input record.
/* get something from the wire */
again:
/* check if we have the header */
- if ((s->rstate != SSL_ST_READ_BODY) ||
- (s->packet_length < DTLS1_RT_HEADER_LENGTH)) {
+ if ((RECORD_LAYER_get_rstate(&s->rlayer) != SSL_ST_READ_BODY) ||
+ (RECORD_LAYER_get_packet_length(&s->rlayer) < DTLS1_RT_HEADER_LENGTH)) {
n = ssl3_read_n(s, DTLS1_RT_HEADER_LENGTH,
- SSL3_BUFFER_get_len(RECORD_LAYER_get_rbuf(&s->rlayer)), 0);
+ SSL3_BUFFER_get_len(&s->rlayer.rbuf), 0);
/* read timeout is handled by dtls1_read_bytes */
if (n <= 0)
return (n); /* error or non-blocking */
/* this packet contained a partial record, dump it */
- if (s->packet_length != DTLS1_RT_HEADER_LENGTH) {
- s->packet_length = 0;
+ if (RECORD_LAYER_get_packet_length(&s->rlayer) != DTLS1_RT_HEADER_LENGTH) {
+ RECORD_LAYER_reset_packet_length(&s->rlayer);
goto again;
}
- s->rstate = SSL_ST_READ_BODY;
+ RECORD_LAYER_set_rstate(&s->rlayer, SSL_ST_READ_BODY);
- p = s->packet;
+ p = RECORD_LAYER_get_packet(&s->rlayer);
if (s->msg_callback)
s->msg_callback(0, 0, SSL3_RT_HEADER, p, DTLS1_RT_HEADER_LENGTH,
/* sequence number is 64 bits, with top 2 bytes = epoch */
n2s(p, rr->epoch);
- memcpy(&(s->s3->read_sequence[2]), p, 6);
+ memcpy(&(RECORD_LAYER_get_read_sequence(&s->rlayer)[2]), p, 6);
p += 6;
n2s(p, rr->length);
if (version != s->version) {
/* unexpected version, silently discard */
rr->length = 0;
- s->packet_length = 0;
+ RECORD_LAYER_reset_packet_length(&s->rlayer);
goto again;
}
}
if ((version & 0xff00) != (s->version & 0xff00)) {
/* wrong version, silently discard record */
rr->length = 0;
- s->packet_length = 0;
+ RECORD_LAYER_reset_packet_length(&s->rlayer);
goto again;
}
if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) {
/* record too long, silently discard it */
rr->length = 0;
- s->packet_length = 0;
+ RECORD_LAYER_reset_packet_length(&s->rlayer);
goto again;
}
- /* now s->rstate == SSL_ST_READ_BODY */
+ /* now s->rlayer.rstate == SSL_ST_READ_BODY */
}
- /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
+ /* s->rlayer.rstate == SSL_ST_READ_BODY, get and decode the data */
- if (rr->length > s->packet_length - DTLS1_RT_HEADER_LENGTH) {
+ if (rr->length >
+ RECORD_LAYER_get_packet_length(&s->rlayer) - DTLS1_RT_HEADER_LENGTH) {
/* now s->packet_length == DTLS1_RT_HEADER_LENGTH */
i = rr->length;
n = ssl3_read_n(s, i, i, 1);
/* this packet contained a partial record, dump it */
if (n != i) {
rr->length = 0;
- s->packet_length = 0;
+ RECORD_LAYER_reset_packet_length(&s->rlayer);
goto again;
}
* DTLS1_RT_HEADER_LENGTH + rr->length
*/
}
- s->rstate = SSL_ST_READ_HEADER; /* set state for later operations */
+ /* set state for later operations */
+ RECORD_LAYER_set_rstate(&s->rlayer, SSL_ST_READ_HEADER);
/* match epochs. NULL means the packet is dropped on the floor */
bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch);
if (bitmap == NULL) {
rr->length = 0;
- s->packet_length = 0; /* dump this record */
+ RECORD_LAYER_reset_packet_length(&s->rlayer); /* dump this record */
goto again; /* get another record */
}
#ifndef OPENSSL_NO_SCTP
/* Only do replay check if no SCTP bio */
if (!BIO_dgram_is_sctp(SSL_get_rbio(s))) {
#endif
- /*
- * Check whether this is a repeat, or aged record. Don't check if
- * we're listening and this message is a ClientHello. They can look
- * as if they're replayed, since they arrive from different
- * connections and would be dropped unnecessarily.
- */
- if (!(s->d1->listen && rr->type == SSL3_RT_HANDSHAKE &&
- s->packet_length > DTLS1_RT_HEADER_LENGTH &&
- s->packet[DTLS1_RT_HEADER_LENGTH] == SSL3_MT_CLIENT_HELLO) &&
- !dtls1_record_replay_check(s, bitmap)) {
+ /* Check whether this is a repeat, or aged record. */
+ if (!dtls1_record_replay_check(s, bitmap)) {
rr->length = 0;
- s->packet_length = 0; /* dump this record */
+ RECORD_LAYER_reset_packet_length(&s->rlayer); /* dump this record */
goto again; /* get another record */
}
#ifndef OPENSSL_NO_SCTP
/*
* If this record is from the next epoch (either HM or ALERT), and a
* handshake is currently in progress, buffer it since it cannot be
- * processed at this time. However, do not buffer anything while
- * listening.
+ * processed at this time.
*/
if (is_next_epoch) {
- if ((SSL_in_init(s) || s->in_handshake) && !s->d1->listen) {
+ if ((SSL_in_init(s) || ossl_statem_get_in_handshake(s))) {
if (dtls1_buffer_record
- (s, &(s->d1->unprocessed_rcds), rr->seq_num) < 0)
+ (s, &(DTLS_RECORD_LAYER_get_unprocessed_rcds(&s->rlayer)),
+ rr->seq_num) < 0)
return -1;
/* Mark receipt of record. */
dtls1_record_bitmap_update(s, bitmap);
}
rr->length = 0;
- s->packet_length = 0;
+ RECORD_LAYER_reset_packet_length(&s->rlayer);
goto again;
}
if (!dtls1_process_record(s)) {
rr->length = 0;
- s->packet_length = 0; /* dump this record */
+ RECORD_LAYER_reset_packet_length(&s->rlayer); /* dump this record */
goto again; /* get another record */
}
dtls1_record_bitmap_update(s, bitmap); /* Mark receipt of record. */
return (1);
}
-
projects / openssl.git / blobdiff