diff options
Diffstat (limited to 'ssl/t1_lib.c')
| -rw-r--r-- | ssl/t1_lib.c | 291 |
1 files changed, 188 insertions, 103 deletions
diff --git a/ssl/t1_lib.c b/ssl/t1_lib.c index 7831046b9261..e60c88bd5b27 100644 --- a/ssl/t1_lib.c +++ b/ssl/t1_lib.c @@ -132,6 +132,9 @@ static int ssl_check_clienthello_tlsext_early(SSL *s); int ssl_check_serverhello_tlsext(SSL *s); #endif +#define CHECKLEN(curr, val, limit) \ + (((curr) >= (limit)) || (size_t)((limit) - (curr)) < (size_t)(val)) + SSL3_ENC_METHOD TLSv1_enc_data = { tls1_enc, tls1_mac, @@ -1263,8 +1266,7 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, if (s->tlsext_hostname != NULL) { /* Add TLS extension servername to the Client Hello message */ - unsigned long size_str; - long lenmax; + size_t size_str; /*- * check for enough space. @@ -1274,10 +1276,8 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, * 2 for hostname length * + hostname length */ - - if ((lenmax = limit - ret - 9) < 0 - || (size_str = - strlen(s->tlsext_hostname)) > (unsigned long)lenmax) + size_str = strlen(s->tlsext_hostname); + if (CHECKLEN(ret, 9 + size_str, limit)) return NULL; /* extension type and length */ @@ -1321,7 +1321,7 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, if (s->srp_ctx.login != NULL) { /* Add TLS extension SRP username to the * Client Hello message */ - int login_len = strlen(s->srp_ctx.login); + size_t login_len = strlen(s->srp_ctx.login); if (login_len > 255 || login_len == 0) { SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR); return NULL; @@ -1333,7 +1333,7 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, * 1 for the srp user identity * + srp user identity length */ - if ((limit - ret - 5 - login_len) < 0) + if (CHECKLEN(ret, 5 + login_len, limit)) return NULL; /* fill in the extension */ @@ -1350,20 +1350,23 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, /* * Add TLS extension ECPointFormats to the ClientHello message */ - long lenmax; const unsigned char *pcurves, *pformats; size_t num_curves, num_formats, curves_list_len; tls1_get_formatlist(s, &pformats, &num_formats); - if ((lenmax = limit - ret - 5) < 0) - return NULL; - if (num_formats > (size_t)lenmax) - return NULL; if (num_formats > 255) { SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR); return NULL; } + /*- + * check for enough space. + * 4 bytes for the ec point formats type and extension length + * 1 byte for the length of the formats + * + formats length + */ + if (CHECKLEN(ret, 5 + num_formats, limit)) + return NULL; s2n(TLSEXT_TYPE_ec_point_formats, ret); /* The point format list has 1-byte length. */ @@ -1379,15 +1382,20 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, if (!tls1_get_curvelist(s, 0, &pcurves, &num_curves)) return NULL; - if ((lenmax = limit - ret - 6) < 0) - return NULL; - if (num_curves > (size_t)lenmax / 2) - return NULL; if (num_curves > 65532 / 2) { SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR); return NULL; } curves_list_len = 2 * num_curves; + /*- + * check for enough space. + * 4 bytes for the ec curves type and extension length + * 2 bytes for the curve list length + * + curve list length + */ + if (CHECKLEN(ret, 6 + curves_list_len, limit)) + return NULL; + s2n(TLSEXT_TYPE_elliptic_curves, ret); s2n(curves_list_len + 2, ret); s2n(curves_list_len, ret); @@ -1397,7 +1405,7 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, # endif /* OPENSSL_NO_EC */ if (!(SSL_get_options(s) & SSL_OP_NO_TICKET)) { - int ticklen; + size_t ticklen; if (!s->new_session && s->session && s->session->tlsext_tick) ticklen = s->session->tlsext_ticklen; else if (s->session && s->tlsext_session_ticket && @@ -1418,11 +1426,11 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, * Check for enough room 2 for extension type, 2 for len rest for * ticket */ - if ((long)(limit - ret - 4 - ticklen) < 0) + if (CHECKLEN(ret, 4 + ticklen, limit)) return NULL; s2n(TLSEXT_TYPE_session_ticket, ret); s2n(ticklen, ret); - if (ticklen) { + if (ticklen > 0) { memcpy(ret, s->session->tlsext_tick, ticklen); ret += ticklen; } @@ -1433,7 +1441,14 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, size_t salglen; const unsigned char *salg; salglen = tls12_get_psigalgs(s, &salg); - if ((size_t)(limit - ret) < salglen + 6) + + /*- + * check for enough space. + * 4 bytes for the sigalgs type and extension length + * 2 bytes for the sigalg list length + * + sigalg list length + */ + if (CHECKLEN(ret, salglen + 6, limit)) return NULL; s2n(TLSEXT_TYPE_signature_algorithms, ret); s2n(salglen + 2, ret); @@ -1460,30 +1475,42 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, if (s->tlsext_status_type == TLSEXT_STATUSTYPE_ocsp) { int i; - long extlen, idlen, itmp; + size_t extlen, idlen; + int lentmp; OCSP_RESPID *id; idlen = 0; for (i = 0; i < sk_OCSP_RESPID_num(s->tlsext_ocsp_ids); i++) { id = sk_OCSP_RESPID_value(s->tlsext_ocsp_ids, i); - itmp = i2d_OCSP_RESPID(id, NULL); - if (itmp <= 0) + lentmp = i2d_OCSP_RESPID(id, NULL); + if (lentmp <= 0) return NULL; - idlen += itmp + 2; + idlen += (size_t)lentmp + 2; } if (s->tlsext_ocsp_exts) { - extlen = i2d_X509_EXTENSIONS(s->tlsext_ocsp_exts, NULL); - if (extlen < 0) + lentmp = i2d_X509_EXTENSIONS(s->tlsext_ocsp_exts, NULL); + if (lentmp < 0) return NULL; + extlen = (size_t)lentmp; } else extlen = 0; - if ((long)(limit - ret - 7 - extlen - idlen) < 0) - return NULL; - s2n(TLSEXT_TYPE_status_request, ret); if (extlen + idlen > 0xFFF0) return NULL; + /* + * 2 bytes for status request type + * 2 bytes for status request len + * 1 byte for OCSP request type + * 2 bytes for length of ids + * 2 bytes for length of extensions + * + length of ids + * + length of extensions + */ + if (CHECKLEN(ret, 9 + idlen + extlen, limit)) + return NULL; + + s2n(TLSEXT_TYPE_status_request, ret); s2n(extlen + idlen + 5, ret); *(ret++) = TLSEXT_STATUSTYPE_ocsp; s2n(idlen, ret); @@ -1493,9 +1520,9 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, id = sk_OCSP_RESPID_value(s->tlsext_ocsp_ids, i); /* skip over id len */ ret += 2; - itmp = i2d_OCSP_RESPID(id, &ret); + lentmp = i2d_OCSP_RESPID(id, &ret); /* write id len */ - s2n(itmp, q); + s2n(lentmp, q); } s2n(extlen, ret); if (extlen > 0) @@ -1503,8 +1530,15 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, } # ifndef OPENSSL_NO_HEARTBEATS /* Add Heartbeat extension */ - if ((limit - ret - 4 - 1) < 0) + + /*- + * check for enough space. + * 4 bytes for the heartbeat ext type and extension length + * 1 byte for the mode + */ + if (CHECKLEN(ret, 5, limit)) return NULL; + s2n(TLSEXT_TYPE_heartbeat, ret); s2n(1, ret); /*- @@ -1524,7 +1558,12 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, * The client advertises an emtpy extension to indicate its support * for Next Protocol Negotiation */ - if (limit - ret - 4 < 0) + + /*- + * check for enough space. + * 4 bytes for the NPN ext type and extension length + */ + if (CHECKLEN(ret, 4, limit)) return NULL; s2n(TLSEXT_TYPE_next_proto_neg, ret); s2n(0, ret); @@ -1532,7 +1571,13 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, # endif if (s->alpn_client_proto_list && !s->s3->tmp.finish_md_len) { - if ((size_t)(limit - ret) < 6 + s->alpn_client_proto_list_len) + /*- + * check for enough space. + * 4 bytes for the ALPN type and extension length + * 2 bytes for the ALPN protocol list length + * + ALPN protocol list length + */ + if (CHECKLEN(ret, 6 + s->alpn_client_proto_list_len, limit)) return NULL; s2n(TLSEXT_TYPE_application_layer_protocol_negotiation, ret); s2n(2 + s->alpn_client_proto_list_len, ret); @@ -1547,7 +1592,12 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, ssl_add_clienthello_use_srtp_ext(s, 0, &el, 0); - if ((limit - ret - 4 - el) < 0) + /*- + * check for enough space. + * 4 bytes for the SRTP type and extension length + * + SRTP profiles length + */ + if (CHECKLEN(ret, 4 + el, limit)) return NULL; s2n(TLSEXT_TYPE_use_srtp, ret); @@ -1587,6 +1637,17 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, else hlen = 0; + /*- + * check for enough space. Strictly speaking we know we've already + * got enough space because to get here the message size is < 0x200, + * but we know that we've allocated far more than that in the buffer + * - but for consistency and robustness we're going to check anyway. + * + * 4 bytes for the padding type and extension length + * + padding length + */ + if (CHECKLEN(ret, 4 + hlen, limit)) + return NULL; s2n(TLSEXT_TYPE_padding, ret); s2n(hlen, ret); memset(ret, 0, hlen); @@ -1644,7 +1705,12 @@ unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *buf, return NULL; } - if ((limit - ret - 4 - el) < 0) + /*- + * check for enough space. + * 4 bytes for the reneg type and extension length + * + reneg data length + */ + if (CHECKLEN(ret, 4 + el, limit)) return NULL; s2n(TLSEXT_TYPE_renegotiate, ret); @@ -1664,19 +1730,23 @@ unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *buf, /* * Add TLS extension ECPointFormats to the ServerHello message */ - long lenmax; tls1_get_formatlist(s, &plist, &plistlen); - if ((lenmax = limit - ret - 5) < 0) - return NULL; - if (plistlen > (size_t)lenmax) - return NULL; if (plistlen > 255) { SSLerr(SSL_F_SSL_ADD_SERVERHELLO_TLSEXT, ERR_R_INTERNAL_ERROR); return NULL; } + /*- + * check for enough space. + * 4 bytes for the ec points format type and extension length + * 1 byte for the points format list length + * + length of points format list + */ + if (CHECKLEN(ret, 5 + plistlen, limit)) + return NULL; + s2n(TLSEXT_TYPE_ec_point_formats, ret); s2n(plistlen + 1, ret); *(ret++) = (unsigned char)plistlen; @@ -1691,14 +1761,22 @@ unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *buf, # endif /* OPENSSL_NO_EC */ if (s->tlsext_ticket_expected && !(SSL_get_options(s) & SSL_OP_NO_TICKET)) { - if ((long)(limit - ret - 4) < 0) + /*- + * check for enough space. + * 4 bytes for the Ticket type and extension length + */ + if (CHECKLEN(ret, 4, limit)) return NULL; s2n(TLSEXT_TYPE_session_ticket, ret); s2n(0, ret); } if (s->tlsext_status_expected) { - if ((long)(limit - ret - 4) < 0) + /*- + * check for enough space. + * 4 bytes for the Status request type and extension length + */ + if (CHECKLEN(ret, 4, limit)) return NULL; s2n(TLSEXT_TYPE_status_request, ret); s2n(0, ret); @@ -1726,7 +1804,12 @@ unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *buf, ssl_add_serverhello_use_srtp_ext(s, 0, &el, 0); - if ((limit - ret - 4 - el) < 0) + /*- + * check for enough space. + * 4 bytes for the SRTP profiles type and extension length + * + length of the SRTP profiles list + */ + if (CHECKLEN(ret, 4 + el, limit)) return NULL; s2n(TLSEXT_TYPE_use_srtp, ret); @@ -1751,16 +1834,23 @@ unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *buf, 0x2a, 0x85, 0x03, 0x02, 0x02, 0x16, 0x30, 0x08, 0x06, 0x06, 0x2a, 0x85, 0x03, 0x02, 0x02, 0x17 }; - if (limit - ret < 36) + + /* check for enough space. */ + if (CHECKLEN(ret, sizeof(cryptopro_ext), limit)) return NULL; - memcpy(ret, cryptopro_ext, 36); - ret += 36; + memcpy(ret, cryptopro_ext, sizeof(cryptopro_ext)); + ret += sizeof(cryptopro_ext); } # ifndef OPENSSL_NO_HEARTBEATS /* Add Heartbeat extension if we've received one */ if (s->tlsext_heartbeat & SSL_TLSEXT_HB_ENABLED) { - if ((limit - ret - 4 - 1) < 0) + /*- + * check for enough space. + * 4 bytes for the Heartbeat type and extension length + * 1 byte for the mode + */ + if (CHECKLEN(ret, 5, limit)) return NULL; s2n(TLSEXT_TYPE_heartbeat, ret); s2n(1, ret); @@ -1789,7 +1879,12 @@ unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *buf, s-> ctx->next_protos_advertised_cb_arg); if (r == SSL_TLSEXT_ERR_OK) { - if ((long)(limit - ret - 4 - npalen) < 0) + /*- + * check for enough space. + * 4 bytes for the NPN type and extension length + * + length of protocols list + */ + if (CHECKLEN(ret, 4 + npalen, limit)) return NULL; s2n(TLSEXT_TYPE_next_proto_neg, ret); s2n(npalen, ret); @@ -1804,9 +1899,16 @@ unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *buf, if (s->s3->alpn_selected) { const unsigned char *selected = s->s3->alpn_selected; - unsigned len = s->s3->alpn_selected_len; + size_t len = s->s3->alpn_selected_len; - if ((long)(limit - ret - 4 - 2 - 1 - len) < 0) + /*- + * check for enough space. + * 4 bytes for the ALPN type and extension length + * 2 bytes for ALPN data length + * 1 byte for selected protocol length + * + length of the selected protocol + */ + if (CHECKLEN(ret, 7 + len, limit)) return NULL; s2n(TLSEXT_TYPE_application_layer_protocol_negotiation, ret); s2n(3 + len, ret); @@ -1966,11 +2068,10 @@ static int tls1_alpn_handle_client_hello(SSL *s, const unsigned char *data, /* * Process the ALPN extension in a ClientHello. - * ret: a pointer to the TLSEXT return value: SSL_TLSEXT_ERR_* * al: a pointer to the alert value to send in the event of a failure. - * returns 1 on success, 0 on failure: al/ret set only on failure + * returns 1 on success, 0 on failure: al set only on failure */ -static int tls1_alpn_handle_client_hello_late(SSL *s, int *ret, int *al) +static int tls1_alpn_handle_client_hello_late(SSL *s, int *al) { const unsigned char *selected = NULL; unsigned char selected_len = 0; @@ -1986,7 +2087,6 @@ static int tls1_alpn_handle_client_hello_late(SSL *s, int *ret, int *al) s->s3->alpn_selected = OPENSSL_malloc(selected_len); if (s->s3->alpn_selected == NULL) { *al = SSL_AD_INTERNAL_ERROR; - *ret = SSL_TLSEXT_ERR_ALERT_FATAL; return 0; } memcpy(s->s3->alpn_selected, selected, selected_len); @@ -3064,10 +3164,12 @@ int tls1_set_server_sigalgs(SSL *s) return 0; } -int ssl_check_clienthello_tlsext_late(SSL *s) +/* + * Upon success, returns 1. + * Upon failure, returns 0 and sets |al| to the appropriate fatal alert. + */ +int ssl_check_clienthello_tlsext_late(SSL *s, int *al) { - int ret = SSL_TLSEXT_ERR_OK; - int al; /* * If status request then ask callback what to do. Note: this must be @@ -3076,58 +3178,41 @@ int ssl_check_clienthello_tlsext_late(SSL *s) * influence which certificate is sent */ if ((s->tlsext_status_type != -1) && s->ctx && s->ctx->tlsext_status_cb) { - int r; + int ret; CERT_PKEY *certpkey; certpkey = ssl_get_server_send_pkey(s); /* If no certificate can't return certificate status */ - if (certpkey == NULL) { - s->tlsext_status_expected = 0; - return 1; - } - /* - * Set current certificate to one we will use so SSL_get_certificate - * et al can pick it up. - */ - s->cert->key = certpkey; - r = s->ctx->tlsext_status_cb(s, s->ctx->tlsext_status_arg); - switch (r) { - /* We don't want to send a status request response */ - case SSL_TLSEXT_ERR_NOACK: - s->tlsext_status_expected = 0; - break; - /* status request response should be sent */ - case SSL_TLSEXT_ERR_OK: - if (s->tlsext_ocsp_resp) - s->tlsext_status_expected = 1; - else + if (certpkey != NULL) { + /* + * Set current certificate to one we will use so SSL_get_certificate + * et al can pick it up. + */ + s->cert->key = certpkey; + ret = s->ctx->tlsext_status_cb(s, s->ctx->tlsext_status_arg); + switch (ret) { + /* We don't want to send a status request response */ + case SSL_TLSEXT_ERR_NOACK: s->tlsext_status_expected = 0; - break; - /* something bad happened */ - case SSL_TLSEXT_ERR_ALERT_FATAL: - ret = SSL_TLSEXT_ERR_ALERT_FATAL; - al = SSL_AD_INTERNAL_ERROR; - goto err; + break; + /* status request response should be sent */ + case SSL_TLSEXT_ERR_OK: + if (s->tlsext_ocsp_resp) + s->tlsext_status_expected = 1; + break; + /* something bad happened */ + case SSL_TLSEXT_ERR_ALERT_FATAL: + default: + *al = SSL_AD_INTERNAL_ERROR; + return 0; + } } - } else - s->tlsext_status_expected = 0; - - if (!tls1_alpn_handle_client_hello_late(s, &ret, &al)) { - goto err; } - err: - switch (ret) { - case SSL_TLSEXT_ERR_ALERT_FATAL: - ssl3_send_alert(s, SSL3_AL_FATAL, al); - return -1; - - case SSL_TLSEXT_ERR_ALERT_WARNING: - ssl3_send_alert(s, SSL3_AL_WARNING, al); - return 1; - - default: - return 1; + if (!tls1_alpn_handle_client_hello_late(s, al)) { + return 0; } + + return 1; } int ssl_check_serverhello_tlsext(SSL *s) |