static inline unsigned int constant_time_lt(unsigned int a, unsigned int b)
{
    return constant_time_msb(a ^ ((a ^ b) | ((a - b) ^ b)));
}
['int dtls1_process_buffered_records(SSL *s)\n{\n    pitem *item;\n    item = pqueue_peek(s->rlayer.d->unprocessed_rcds.q);\n    if (item) {\n        if (s->rlayer.d->unprocessed_rcds.epoch != s->rlayer.d->r_epoch)\n            return (1);\n        while (pqueue_peek(s->rlayer.d->unprocessed_rcds.q)) {\n            dtls1_get_unprocessed_record(s);\n            if (!dtls1_process_record(s))\n                return (0);\n            if (dtls1_buffer_record(s, &(s->rlayer.d->processed_rcds),\n                SSL3_RECORD_get_seq_num(&s->rlayer.rrec)) < 0)\n                return -1;\n        }\n    }\n    s->rlayer.d->processed_rcds.epoch = s->rlayer.d->r_epoch;\n    s->rlayer.d->unprocessed_rcds.epoch = s->rlayer.d->r_epoch + 1;\n    return (1);\n}', 'int dtls1_process_record(SSL *s)\n{\n    int i, al;\n    int enc_err;\n    SSL_SESSION *sess;\n    SSL3_RECORD *rr;\n    unsigned int mac_size;\n    unsigned char md[EVP_MAX_MD_SIZE];\n    rr = RECORD_LAYER_get_rrec(&s->rlayer);\n    sess = s->session;\n    rr->input = &(RECORD_LAYER_get_packet(&s->rlayer)[DTLS1_RT_HEADER_LENGTH]);\n    if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) {\n        al = SSL_AD_RECORD_OVERFLOW;\n        SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_ENCRYPTED_LENGTH_TOO_LONG);\n        goto f_err;\n    }\n    rr->data = rr->input;\n    rr->orig_len = rr->length;\n    enc_err = s->method->ssl3_enc->enc(s, 0);\n    if (enc_err == 0) {\n        rr->length = 0;\n        RECORD_LAYER_reset_packet_length(&s->rlayer);\n        goto err;\n    }\n#ifdef TLS_DEBUG\n    printf("dec %d\\n", rr->length);\n    {\n        unsigned int z;\n        for (z = 0; z < rr->length; z++)\n            printf("%02X%c", rr->data[z], ((z + 1) % 16) ? \' \' : \'\\n\');\n    }\n    printf("\\n");\n#endif\n    if ((sess != NULL) &&\n        (s->enc_read_ctx != NULL) && (EVP_MD_CTX_md(s->read_hash) != NULL)) {\n        unsigned char *mac = NULL;\n        unsigned char mac_tmp[EVP_MAX_MD_SIZE];\n        mac_size = EVP_MD_CTX_size(s->read_hash);\n        OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);\n        if (rr->orig_len < mac_size ||\n            (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&\n             rr->orig_len < mac_size + 1)) {\n            al = SSL_AD_DECODE_ERROR;\n            SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_LENGTH_TOO_SHORT);\n            goto f_err;\n        }\n        if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE) {\n            mac = mac_tmp;\n            ssl3_cbc_copy_mac(mac_tmp, rr, mac_size);\n            rr->length -= mac_size;\n        } else {\n            rr->length -= mac_size;\n            mac = &rr->data[rr->length];\n        }\n        i = s->method->ssl3_enc->mac(s, md, 0   );\n        if (i < 0 || mac == NULL\n            || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)\n            enc_err = -1;\n        if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + mac_size)\n            enc_err = -1;\n    }\n    if (enc_err < 0) {\n        rr->length = 0;\n        RECORD_LAYER_reset_packet_length(&s->rlayer);\n        goto err;\n    }\n    if (s->expand != NULL) {\n        if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH) {\n            al = SSL_AD_RECORD_OVERFLOW;\n            SSLerr(SSL_F_DTLS1_PROCESS_RECORD,\n                   SSL_R_COMPRESSED_LENGTH_TOO_LONG);\n            goto f_err;\n        }\n        if (!ssl3_do_uncompress(s)) {\n            al = SSL_AD_DECOMPRESSION_FAILURE;\n            SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_BAD_DECOMPRESSION);\n            goto f_err;\n        }\n    }\n    if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH) {\n        al = SSL_AD_RECORD_OVERFLOW;\n        SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_DATA_LENGTH_TOO_LONG);\n        goto f_err;\n    }\n    rr->off = 0;\n    RECORD_LAYER_reset_packet_length(&s->rlayer);\n    return (1);\n f_err:\n    ssl3_send_alert(s, SSL3_AL_FATAL, al);\n err:\n    return (0);\n}', 'void ssl3_cbc_copy_mac(unsigned char *out,\n                       const SSL3_RECORD *rec, unsigned md_size)\n{\n#if defined(CBC_MAC_ROTATE_IN_PLACE)\n    unsigned char rotated_mac_buf[64 + EVP_MAX_MD_SIZE];\n    unsigned char *rotated_mac;\n#else\n    unsigned char rotated_mac[EVP_MAX_MD_SIZE];\n#endif\n    unsigned mac_end = rec->length;\n    unsigned mac_start = mac_end - md_size;\n    unsigned scan_start = 0;\n    unsigned i, j;\n    unsigned div_spoiler;\n    unsigned rotate_offset;\n    OPENSSL_assert(rec->orig_len >= md_size);\n    OPENSSL_assert(md_size <= EVP_MAX_MD_SIZE);\n#if defined(CBC_MAC_ROTATE_IN_PLACE)\n    rotated_mac = rotated_mac_buf + ((0 - (size_t)rotated_mac_buf) & 63);\n#endif\n    if (rec->orig_len > md_size + 255 + 1)\n        scan_start = rec->orig_len - (md_size + 255 + 1);\n    div_spoiler = md_size >> 1;\n    div_spoiler <<= (sizeof(div_spoiler) - 1) * 8;\n    rotate_offset = (div_spoiler + mac_start - scan_start) % md_size;\n    memset(rotated_mac, 0, md_size);\n    for (i = scan_start, j = 0; i < rec->orig_len; i++) {\n        unsigned char mac_started = constant_time_ge_8(i, mac_start);\n        unsigned char mac_ended = constant_time_ge_8(i, mac_end);\n        unsigned char b = rec->data[i];\n        rotated_mac[j++] |= b & mac_started & ~mac_ended;\n        j &= constant_time_lt(j, md_size);\n    }\n#if defined(CBC_MAC_ROTATE_IN_PLACE)\n    j = 0;\n    for (i = 0; i < md_size; i++) {\n        ((volatile unsigned char *)rotated_mac)[rotate_offset ^ 32];\n        out[j++] = rotated_mac[rotate_offset++];\n        rotate_offset &= constant_time_lt(rotate_offset, md_size);\n    }\n#else\n    memset(out, 0, md_size);\n    rotate_offset = md_size - rotate_offset;\n    rotate_offset &= constant_time_lt(rotate_offset, md_size);\n    for (i = 0; i < md_size; i++) {\n        for (j = 0; j < md_size; j++)\n            out[j] |= rotated_mac[i] & constant_time_eq_8(j, rotate_offset);\n        rotate_offset++;\n        rotate_offset &= constant_time_lt(rotate_offset, md_size);\n    }\n#endif\n}', 'static inline unsigned char constant_time_ge_8(unsigned int a, unsigned int b)\n{\n    return (unsigned char)(constant_time_ge(a, b));\n}', 'static inline unsigned int constant_time_ge(unsigned int a, unsigned int b)\n{\n    return ~constant_time_lt(a, b);\n}', 'static inline unsigned int constant_time_lt(unsigned int a, unsigned int b)\n{\n    return constant_time_msb(a ^ ((a ^ b) | ((a - b) ^ b)));\n}']