// Copyright (c) Vitaliy Filippov, 2019+
// License: VNPL-1.1 or GNU GPL-2.0+ (see README.md for details)

#define _XOPEN_SOURCE
#include <limits.h>
#include <sys/epoll.h>

#include "messenger.h"
#include "msgr_iothread.h"

#include <openssl/evp.h>
#include <openssl/err.h>

#define WR_GCM     1
#define WR_XTS     2
#define WR_NO_CSUM 4

#define GCM_TMP_BUF_SIZE 4096

class msgr_op_writer_t
{
public:
    virtual bool write(uint8_t *src, size_t src_len, int flags = 0) = 0;
    virtual bool finish() = 0;
};

class copy_op_writer_t: public msgr_op_writer_t
{
protected:
    osd_messenger_t* msgr;
    osd_client_t* cl;
    size_t from;

    uint8_t *curbuf;
    size_t bufsize;
    size_t done;

public:
    copy_op_writer_t(osd_messenger_t* msgr, osd_client_t* cl, uint8_t *curbuf, size_t bufsize):
        msgr(msgr), cl(cl), from(cl->write_op_pos), curbuf(curbuf), bufsize(bufsize), done(0)
    {}

    void reset()
    {
        from = cl->write_op_pos;
    }

    bool write(uint8_t *src, size_t src_len, int flags = 0) override
    {
        if (from >= src_len)
        {
            from -= src_len;
            return true;
        }
        if (flags & WR_XTS)
        {
            msgr->op_encrypted_copy_buf(cl, curbuf, bufsize, src, src_len, from, done);
        }
        else
        {
            size_t n = src_len-from;
            if (n > bufsize-done)
                n = bufsize-done;
            if (cl->write_csum_state && !(flags & WR_NO_CSUM))
                XXH3_64bits_update(cl->write_csum_state, src+from, n);
            memcpy(curbuf+done, src+from, n);
            done += n;
            cl->write_op_pos += n;
            from += n;
        }
        if (from < src_len)
            return false;
        from = 0;
        return true;
    }

    bool finish() override
    {
        return true;
    }

    size_t get_done()
    {
        return done;
    }
};

class gcm_op_writer_t: public msgr_op_writer_t
{
    osd_messenger_t* msgr;
    osd_client_t* cl;
    size_t from;

    uint8_t *curbuf;
    size_t bufsize;
    size_t done;

public:
    gcm_op_writer_t(osd_messenger_t* msgr, osd_client_t* cl, uint8_t *curbuf, size_t bufsize):
        msgr(msgr), cl(cl), from(cl->write_op_pos), curbuf(curbuf), bufsize(bufsize), done(0)
    {
    }

    void reset()
    {
        from = cl->write_op_pos;
        init_ctx(msgr, cl);
    }

    static void init_ctx(osd_messenger_t* msgr, osd_client_t *cl)
    {
        if (!cl->enc_ctx)
        {
            if (msgr->encrypt_gcm_pool.size())
            {
                cl->enc_ctx = msgr->encrypt_gcm_pool.back();
                msgr->encrypt_gcm_pool.pop_back();
            }
            else
            {
#ifdef WITH_ISAL_CRYPTO
                cl->enc_ctx = (isal_gcm_context_data*)malloc_or_die(sizeof(isal_gcm_context_data));
#else
                cl->enc_ctx = EVP_CIPHER_CTX_new();
                assert(cl->enc_ctx);
                int r = EVP_EncryptInit_ex(cl->enc_ctx, EVP_aes_256_gcm(), NULL, NULL, NULL);
                if (r != 1)
                {
                    fprintf(stderr, "EncryptInit error: ");
                    ERR_print_errors_fp(stderr);
                    abort();
                }
#endif
            }
        }
        if (cl->my_iv_ctr >= AES_256_GCM_MAX_IV_CTR)
        {
            // Rotate key every 2^32 messages
            bool ok = msgr->derive_aes_keys(cl, true, false);
            assert(ok);
        }
#ifdef WITH_ISAL_CRYPTO
        int r = isal_aes_gcm_init_256(&cl->my_key_isal, cl->enc_ctx, cl->my_key.data() + AES_256_GCM_KEY_SIZE, NULL, 0);
        if (r != 0)
        {
            fprintf(stderr, "isal_aes_gcm_init_256 error %d\n", r);
            abort();
        }
#else
        int r = EVP_EncryptInit_ex(cl->enc_ctx, NULL, NULL, (uint8_t*)cl->my_key.data(), cl->my_key.data() + AES_256_GCM_KEY_SIZE);
        if (r != 1)
        {
            fprintf(stderr, "EncryptInit error: ");
            ERR_print_errors_fp(stderr);
            abort();
        }
#endif
        // Increase IV
        cl->my_iv_ctr++;
        (*(uint64_t*)(cl->my_key.data() + AES_256_GCM_KEY_SIZE))++;
    }

    static void free_ctx(osd_messenger_t* msgr, osd_client_t *cl)
    {
        if (msgr->encrypt_gcm_pool.size() < msgr->max_cipher_pool_size)
            msgr->encrypt_gcm_pool.push_back(cl->enc_ctx);
        else
        {
#ifdef WITH_ISAL_CRYPTO
            free(cl->enc_ctx);
#else
            EVP_CIPHER_CTX_free(cl->enc_ctx);
#endif
        }
        cl->enc_ctx = NULL;
    }

    bool write(uint8_t *src, size_t src_len, int flags) override
    {
        if (from >= src_len)
        {
            from -= src_len;
            return true;
        }
        if (flags & WR_XTS)
        {
            msgr->op_encrypted_copy_buf(cl, curbuf, bufsize, src, src_len, from, done);
        }
        else if (flags & WR_GCM)
        {
            size_t n = src_len-from;
            if (n > bufsize-done)
                n = bufsize-done;
            if (!n)
                return false;
#ifdef WITH_ISAL_CRYPTO
            int r = isal_aes_gcm_enc_256_update(&cl->my_key_isal, cl->enc_ctx, curbuf+done, src+from, n);
            assert(!r);
#else
            int actual_out;
            if (EVP_EncryptUpdate(cl->enc_ctx, curbuf+done, &actual_out, src+from, n) != 1)
            {
                fprintf(stderr, "EncryptUpdate error: ");
                ERR_print_errors_fp(stderr);
                abort();
            }
            assert(actual_out == n);
#endif
            if (cl->write_csum_state && !(flags & WR_NO_CSUM))
                XXH3_64bits_update(cl->write_csum_state, src+from, n);
            done += n;
            cl->write_op_pos += n;
            from += n;
        }
        else
        {
            size_t n = src_len-from;
            if (n > bufsize-done)
                n = bufsize-done;
            if (!n)
                return false;
            if (cl->write_csum_state && !(flags & WR_NO_CSUM))
                XXH3_64bits_update(cl->write_csum_state, src+from, n);
            memcpy(curbuf+done, src+from, n);
            done += n;
            cl->write_op_pos += n;
            from += n;
        }
        if (from < src_len)
            return false;
        from = 0;
        return true;
    }

    static void write_tag_to(osd_messenger_t *msgr, osd_client_t *cl, uint8_t *dst)
    {
#ifdef WITH_ISAL_CRYPTO
        int r = isal_aes_gcm_enc_256_finalize(&cl->my_key_isal, cl->enc_ctx, dst, 16);
        assert(!r);
#else
        int actual_out = 0;
        int r = EVP_EncryptFinal_ex(cl->enc_ctx, NULL, &actual_out);
        if (r != 1)
        {
            fprintf(stderr, "EncryptFinal error: ");
            ERR_print_errors_fp(stderr);
            abort();
        }
        assert(actual_out == 0);
        r = EVP_CIPHER_CTX_ctrl(cl->enc_ctx, EVP_CTRL_GCM_GET_TAG, 16, dst);
        assert(r == 1);
#endif
    }

    bool finish() override
    {
        // Tag is 16 bytes
        if (done >= bufsize)
            return false;
        if (bufsize-done < 16 || cl->enc_tag_size)
        {
            // No space for the full tag, but msgr_rdma expects us to always fill the whole buffer
            if (!cl->enc_tag_size)
            {
                write_tag_to(msgr, cl, cl->enc_tag);
                cl->enc_tag_size = 16;
            }
            size_t n = bufsize-done;
            if (n > cl->enc_tag_size)
                n = cl->enc_tag_size;
            memcpy(curbuf+done, cl->enc_tag+16-cl->enc_tag_size, n);
            done += n;
            cl->enc_tag_size -= n;
            if (cl->enc_tag_size > 0)
                return false;
        }
        else
        {
            // The whole tag fits at once
            write_tag_to(msgr, cl, curbuf+done);
            done += 16;
        }
        free_ctx(msgr, cl);
        return true;
    }

    size_t get_done()
    {
        return done;
    }
};

class get_op_writer_t: public msgr_op_writer_t
{
    osd_messenger_t* msgr;
    osd_client_t* cl;
    size_t from;
    size_t done;
    size_t op_enc;
    size_t enc_size;
    size_t done_enc;
    uint8_t *enc_buf;

public:
    get_op_writer_t(osd_messenger_t* msgr, osd_client_t* cl, uint8_t*, size_t):
        msgr(msgr), cl(cl), from(cl->write_op_pos), done(0), enc_size(0), done_enc(0), enc_buf(NULL)
    {
    }

    void reset()
    {
        op_enc = 0;
        from = cl->write_op_pos;
        if (cl->gcm_enabled)
        {
            gcm_op_writer_t::init_ctx(msgr, cl);
        }
    }

    void extend_tmp(size_t n)
    {
        if (!enc_buf || done_enc + n > enc_size)
        {
            enc_size = n < GCM_TMP_BUF_SIZE ? GCM_TMP_BUF_SIZE : n;
            enc_buf = (uint8_t*)malloc_or_die(enc_size);
            done_enc = 0;
            assert(!((size_t)enc_buf & 7));
            cl->send_free_ops.push_back((osd_op_t*)((size_t)enc_buf | 1));
        }
    }

    void send_tmp(size_t n)
    {
        if (cl->send_list.size() && cl->send_list.back().iov_base == (enc_buf + done_enc))
            cl->send_list.back().iov_len += n;
        else
            cl->send_list.push_back((iovec){ .iov_base = enc_buf + done_enc, .iov_len = n });
        done += n;
        done_enc += n;
    }

    bool write(uint8_t *src, size_t src_len, int flags) override
    {
        if (from >= src_len)
        {
            // Skip
            from -= src_len;
            return true;
        }
        if (cl->send_list.size() >= IOV_MAX-1)
        {
            // Make sure tag always fits
            return false;
        }
        if (flags & WR_XTS)
        {
            // Allocate a temporary buffer and encrypt data to it
            if (!op_enc)
            {
                assert(cl->write_op->req.hdr.opcode == OSD_OP_WRITE);
                op_enc = cl->write_op->req.rw.len - from + (from % 16);
                assert(op_enc > 0);
                extend_tmp(op_enc);
            }
            size_t new_done = done_enc;
            msgr->op_encrypted_copy_buf(cl, enc_buf, enc_size, src, src_len, from, new_done);
            send_tmp(new_done-done_enc);
            assert(from == src_len);
        }
        else if ((flags & WR_GCM) && cl->gcm_enabled)
        {
            // Allocate a temporary buffer and encrypt data to it
            size_t n = src_len-from;
            extend_tmp(n);
#ifdef WITH_ISAL_CRYPTO
            int r = isal_aes_gcm_enc_256_update(&cl->my_key_isal, cl->enc_ctx, enc_buf+done_enc, src+from, n);
            assert(!r);
#else
            int actual_out;
            if (EVP_EncryptUpdate(cl->enc_ctx, enc_buf+done_enc, &actual_out, src+from, n) != 1)
            {
                fprintf(stderr, "EncryptUpdate error: ");
                ERR_print_errors_fp(stderr);
                abort();
            }
            assert(actual_out == n);
#endif
            if (cl->write_csum_state && !(flags & WR_NO_CSUM))
                XXH3_64bits_update(cl->write_csum_state, src+from, n);
            send_tmp(n);
            cl->write_op_pos += n;
            from += n;
            if (from < src_len)
                return false;
            from = 0;
            return true;
        }
        else
        {
            if (cl->write_csum_state && !(flags & WR_NO_CSUM))
                XXH3_64bits_update(cl->write_csum_state, src+from, src_len-from);
            cl->send_list.push_back((iovec){ src+from, src_len-from });
            done += src_len-from;
            cl->write_op_pos += src_len-from;
        }
        from = 0;
        return true;
    }

    bool finish() override
    {
        if (cl->enc_ctx)
        {
            // Tag is 16 bytes
            extend_tmp(16);
            gcm_op_writer_t::write_tag_to(msgr, cl, enc_buf + done_enc);
            send_tmp(16);
            gcm_op_writer_t::free_ctx(msgr, cl);
        }
        return true;
    }

    size_t get_done()
    {
        return done;
    }
};

void osd_messenger_t::outbox_push(osd_op_t *cur_op)
{
    assert(cur_op->client_id);
    auto cl_it = clients.find(cur_op->client_id);
    if (cl_it == clients.end() || cl_it->second->peer_state == PEER_STOPPED)
    {
        delete cur_op;
        return;
    }
    osd_client_t *cl = cl_it->second;
    if (cur_op->op_type == OSD_OP_OUT)
    {
        clock_gettime(CLOCK_REALTIME, &cur_op->tv_begin);
        cur_op->req.hdr.id = ++cl->send_op_id;
        cl->sent_ops[cur_op->req.hdr.id] = cur_op;
    }
    else
    {
        // Remove the operation from received op list
        bool found = false;
        for (auto it = cl->received_ops.begin(); it != cl->received_ops.end(); it++)
        {
            if (*it == cur_op)
            {
                found = true;
                cl->received_ops.erase(it, it+1);
                break;
            }
        }
        // Can't be not found because client IDs are unique
        assert(found);
        measure_exec(cur_op);
    }
    cl->write_ops.push_back(cur_op);
#ifdef WITH_RDMA
    if (cl->peer_state == PEER_RDMA)
    {
        try_send_rdma(cl);
        return;
    }
#endif
    if (!ringloop)
    {
        // FIXME: It's worse because it doesn't allow batching
        while (cl->write_op || cl->write_ops.size())
        {
            try_send(cl);
        }
    }
    else
    {
        if (!try_send(cl) && cl->write_state == 0)
        {
            cl->write_state = CL_WRITE_READY;
            write_ready_clients.push_back(cl->client_id);
        }
        ringloop->wakeup();
    }
}

void osd_messenger_t::inc_op_stats(osd_op_stats_t & stats, uint64_t opcode, timespec & tv_begin, timespec & tv_end, uint64_t len)
{
    uint64_t usecs = (
        (tv_end.tv_sec - tv_begin.tv_sec)*1000000 +
        (tv_end.tv_nsec - tv_begin.tv_nsec)/1000
    );
    stats.op_stat_count[opcode]++;
    if (!stats.op_stat_count[opcode])
    {
        stats.op_stat_count[opcode] = 1;
        stats.op_stat_sum[opcode] = 0;
        stats.op_stat_bytes[opcode] = 0;
    }
    stats.op_stat_sum[opcode] += usecs;
    stats.op_stat_bytes[opcode] += len;
}

void osd_messenger_t::measure_exec(osd_op_t *cur_op)
{
    // Measure execution latency
    if (cur_op->req.hdr.opcode > OSD_OP_MAX)
    {
        return;
    }
    if (!cur_op->tv_end.tv_sec)
    {
        clock_gettime(CLOCK_REALTIME, &cur_op->tv_end);
    }
    uint64_t len = 0;
    if (cur_op->req.hdr.opcode == OSD_OP_READ ||
        cur_op->req.hdr.opcode == OSD_OP_WRITE ||
        cur_op->req.hdr.opcode == OSD_OP_SCRUB)
    {
        // req.rw.len is internally set to the full object size for scrubs
        len = cur_op->req.rw.len;
    }
    else if (cur_op->req.hdr.opcode == OSD_OP_SEC_READ ||
        cur_op->req.hdr.opcode == OSD_OP_SEC_WRITE ||
        cur_op->req.hdr.opcode == OSD_OP_SEC_WRITE_STABLE)
    {
        len = cur_op->req.sec_rw.len;
    }
    inc_op_stats(stats, cur_op->req.hdr.opcode, cur_op->tv_begin, cur_op->tv_end, len);
    if (cur_op->is_recovery_related())
    {
        inc_op_stats(recovery_stats, cur_op->req.hdr.opcode, cur_op->tv_begin, cur_op->tv_end, len);
    }
}

bool osd_messenger_t::try_send(osd_client_t *cl)
{
    if (cl->peer_state == PEER_STOPPED || cl->peer_fd < 0)
    {
        return true;
    }
    if (cl->write_msg.msg_iovlen > 0 || !ringloop->space_left() && !use_sync_send_recv)
    {
        return false;
    }
    assert(cl->peer_state != PEER_RDMA);
    if (cl->hs)
    {
        // Send handshake message
        if (cl->hs->out_size())
        {
            uint8_t *out = cl->hs->get_out();
            cl->send_list.push_back((iovec){ .iov_base = out, .iov_len = cl->hs->out_size() });
            assert(!((size_t)out & 7));
            cl->send_free_ops.push_back((osd_op_t*)((size_t)out | 1));
            cl->hs->reset_out();
        }
        if (!cl->hs->out_size() && cl->hs->done())
        {
            delete cl->hs;
            cl->hs = NULL;
            goto copy_ops;
        }
    }
    else
    {
copy_ops:
        copy_ops_to_with<get_op_writer_t>(cl, NULL, 0);
    }
    if (cl->io_error)
    {
        stop_client(cl->client_id);
        return true;
    }
    if (!cl->send_list.size())
    {
        cl->write_state = 0;
        return true;
    }
    if (!use_sync_send_recv)
    {
        auto iothread = iothreads.size() ? iothreads[cl->peer_fd % iothreads.size()] : NULL;
        io_uring_sqe sqe_local;
        ring_data_t data_local;
        io_uring_sqe* sqe = (iothread ? &sqe_local : ringloop->get_sqe());
        if (iothread)
        {
            sqe_local = { .user_data = (uint64_t)&data_local };
            data_local = {};
        }
        assert(sqe);
        cl->send_list_size = 0;
        for (auto & iov: cl->send_list)
        {
            cl->send_list_size += iov.iov_len;
        }
        cl->write_msg.msg_iov = cl->send_list.data();
        cl->write_msg.msg_iovlen = cl->send_list.size() < IOV_MAX ? cl->send_list.size() : IOV_MAX;
        cl->refs++;
        ring_data_t* data = ((ring_data_t*)sqe->user_data);
        data->callback = [this, cl](ring_data_t *data) { handle_send(data->res, data->prev, data->more, cl); };
        bool use_zc = has_sendmsg_zc && min_zerocopy_send_size >= 0;
        if (use_zc && min_zerocopy_send_size > 0 &&
            cl->send_list_size/cl->write_msg.msg_iovlen < min_zerocopy_send_size)
        {
            use_zc = false;
        }
        if (use_zc)
        {
            io_uring_prep_sendmsg_zc(sqe, cl->peer_fd, &cl->write_msg, MSG_WAITALL);
        }
        else
        {
            io_uring_prep_sendmsg(sqe, cl->peer_fd, &cl->write_msg, MSG_WAITALL);
        }
        if (iothread)
        {
            iothread->add_sqe(sqe_local);
        }
    }
    else
    {
        cl->write_msg.msg_iov = cl->send_list.data();
        cl->write_msg.msg_iovlen = cl->send_list.size() < IOV_MAX ? cl->send_list.size() : IOV_MAX;
        cl->refs++;
        int result = sendmsg(cl->peer_fd, &cl->write_msg, MSG_NOSIGNAL);
        if (result < 0)
        {
            result = -errno;
        }
        // like set_immediate
        tfd->set_timer_us(0, false, [this, result, cl](int){ handle_send(result, false, false, cl); });
    }
    return true;
}

size_t osd_messenger_t::copy_ops_to(osd_client_t *cl, uint8_t *dst, size_t dst_len)
{
    if (cl->gcm_enabled)
    {
        if (cl->hs)
        {
            // Send handshake message
            size_t n = 0;
            if (cl->hs->out_size())
            {
                n = cl->hs->out_size() < dst_len ? cl->hs->out_size() : dst_len;
                memcpy(dst, cl->hs->get_out(), n);
                cl->hs->eat_out(n);
            }
            if (!cl->hs->out_size() && cl->hs->done())
            {
                delete cl->hs;
                cl->hs = NULL;
                n += copy_ops_to_with<gcm_op_writer_t>(cl, dst+n, dst_len-n);
            }
            return n;
        }
        return copy_ops_to_with<gcm_op_writer_t>(cl, dst, dst_len);
    }
    return copy_ops_to_with<copy_op_writer_t>(cl, dst, dst_len);
}

template<typename T>
size_t osd_messenger_t::copy_ops_to_with(osd_client_t *cl, uint8_t *dst, size_t dst_len)
{
    T wr(this, cl, dst, dst_len);
    while (cl->write_op || cl->write_ops.size())
    {
        if (!cl->write_op)
        {
            wr.reset();
            next_write_op(cl);
        }
        osd_op_t *op = cl->write_op;
        if (!op_write_to(cl, wr))
        {
            if (cl->io_error)
                return 0;
            break;
        }
        if (!cl->write_op && op->op_type == OSD_OP_IN)
        {
            // this is a reply, free the op after sending it
            cl->send_free_ops.push_back(op);
        }
    }
    return wr.get_done();
}

void osd_messenger_t::next_write_op(osd_client_t *cl)
{
    cl->write_op = cl->write_ops.front();
    cl->write_ops.pop_front();
    if (cl->proto_csum_status == MSGR_CSUM_FULL || cl->proto_csum_status == MSGR_CSUM_PAYLOAD)
    {
        if (!cl->write_csum_state)
            cl->write_csum_state = XXH3_createState();
        if (cl->my_key.size() == AES_256_GCM_KEY_SIZE + AES_256_GCM_IV_SIZE + XXH_SECRET_DEFAULT_SIZE)
            XXH3_64bits_reset_withSecret(cl->write_csum_state, cl->my_key.data() + AES_256_GCM_KEY_SIZE + AES_256_GCM_IV_SIZE, XXH_SECRET_DEFAULT_SIZE);
        else
            XXH3_64bits_reset(cl->write_csum_state);
    }
}

void osd_messenger_t::send_replies()
{
    for (int i = 0; i < write_ready_clients.size(); i++)
    {
        uint64_t client_id = write_ready_clients[i];
        auto cl_it = clients.find(client_id);
        if (cl_it != clients.end() && cl_it->second->peer_state != PEER_RDMA && !try_send(cl_it->second))
        {
            write_ready_clients.erase(write_ready_clients.begin(), write_ready_clients.begin() + i);
            return;
        }
    }
    write_ready_clients.clear();
}

void osd_messenger_t::handle_send(int result, bool prev, bool more, osd_client_t *cl)
{
    if (!prev)
    {
        cl->write_msg.msg_iovlen = 0;
        cl->send_list.clear();
    }
    if (!more)
    {
        cl->refs--;
    }
    if (cl->peer_state == PEER_STOPPED)
    {
        if (cl->refs <= 0)
        {
            destroy_client(cl);
        }
        return;
    }
    if (result < 0 && result != -EAGAIN && result != -EINTR)
    {
        // this is a client socket, so don't panic. just disconnect it
        fprintf(stderr, "Client %ju socket write error: %d (%s). Disconnecting client\n", cl->client_id, -result, strerror(-result));
        stop_client(cl->client_id);
        return;
    }
    if (result >= 0)
    {
        if (prev)
        {
            // Second notification - only free a batch of postponed ops
            int i = 0;
            for (; i < cl->zc_free_list.size() && cl->zc_free_list[i]; i++)
            {
                if (!((size_t)cl->zc_free_list[i] & 7))
                    delete cl->zc_free_list[i];
                else
                    free((void*)((size_t)cl->zc_free_list[i] & ~(size_t)7));
            }
            if (i > 0)
                cl->zc_free_list.erase(cl->zc_free_list.begin(), cl->zc_free_list.begin()+i+1);
            return;
        }
        if (cl->send_list_size > result)
        {
            fprintf(stderr, "Client %ju socket write error: expected to send "
                "%zu bytes with MSG_WAITALL but sent %u. Disconnecting client\n", cl->client_id, cl->send_list_size, result);
            stop_client(cl->client_id);
            return;
        }
        for (auto op: cl->send_free_ops)
        {
            if (more)
                cl->zc_free_list.push_back(op);
            else if (!((size_t)op & 7))
                delete op;
            else
                free((void*)((size_t)op & ~(size_t)7));
        }
        if (more)
            cl->zc_free_list.push_back(NULL); // end marker
        cl->send_free_ops.clear();
        cl->write_state = 0;
        if (cl->write_op || cl->write_ops.size())
            cl->write_state = CL_WRITE_READY;
        if ((cl->proto_csum_status & MSGR_CSUM_NEG) && !cl->write_op && !cl->write_ops.size())
        {
            // Checksums negotiated, enable
            cl->proto_csum_status = cl->proto_csum_status & (~MSGR_CSUM_NEG);
        }
#ifdef WITH_RDMA
        if (cl->rdma_conn && !cl->write_op && !cl->write_ops.size() && cl->peer_state == PEER_RDMA_CONNECTING)
        {
            // FIXME: Ignore pings during RDMA state transition
            if (log_level > 0)
            {
                fprintf(stderr, "Successfully connected with client %ju using RDMA\n", cl->client_id);
            }
            cl->peer_state = PEER_RDMA;
            // Add the initial receive request
            init_recv_rdma(cl);
        }
#endif
    }
    if (cl->write_state != 0)
    {
        write_ready_clients.push_back(cl->client_id);
    }
}

static inline bool op_has_data_for_ssl(osd_op_t *op)
{
    return (op->op_type == OSD_OP_IN
        ? (op->req.hdr.opcode == OSD_OP_SEC_LIST ||
        op->req.hdr.opcode == OSD_OP_SHOW_CONFIG ||
        op->req.hdr.opcode == OSD_OP_DESCRIBE)
        : (op->req.hdr.opcode == OSD_OP_SEC_STABILIZE ||
        op->req.hdr.opcode == OSD_OP_SEC_ROLLBACK ||
        op->req.hdr.opcode == OSD_OP_SHOW_CONFIG)) && op->iov.count > 0;
}

static inline bool op_has_data_for_nonssl(osd_op_t *op)
{
    return (op->op_type == OSD_OP_IN
        ? (op->req.hdr.opcode == OSD_OP_READ ||
        op->req.hdr.opcode == OSD_OP_SEC_READ)
        : (op->req.hdr.opcode == OSD_OP_WRITE ||
        op->req.hdr.opcode == OSD_OP_SEC_WRITE ||
        op->req.hdr.opcode == OSD_OP_SEC_WRITE_STABLE)) && op->iov.count > 0;
}

bool osd_messenger_t::op_write_to(osd_client_t *cl, msgr_op_writer_t & wr)
{
    osd_op_t *op = cl->write_op;
    // Header
    if (!wr.write((op->op_type == OSD_OP_IN ? op->reply.buf : op->req.buf), OSD_PACKET_SIZE,
        WR_GCM | (cl->proto_csum_status == MSGR_CSUM_PAYLOAD ? WR_NO_CSUM : 0)))
    {
        return false;
    }
    // Bitmap
    if (op->op_type == OSD_OP_IN)
    {
        if (op->req.hdr.opcode == OSD_OP_SEC_READ && op->reply.sec_rw.attr_len > 0)
        {
            if (!wr.write((uint8_t*)op->bitmap, op->reply.sec_rw.attr_len, WR_GCM))
                return false;
        }
        else if (op->req.hdr.opcode == OSD_OP_SEC_READ_BMP && op->reply.hdr.retval > 0)
        {
            if (!wr.write((uint8_t*)op->buf, (size_t)op->reply.hdr.retval, WR_GCM))
                return false;
        }
        else if (op->req.hdr.opcode == OSD_OP_READ && op->reply.rw.bitmap_len > 0)
        {
            if (!wr.write((uint8_t*)op->bitmap, op->reply.rw.bitmap_len, WR_GCM))
                return false;
        }
    }
    else if (op->op_type == OSD_OP_OUT)
    {
        if ((op->req.hdr.opcode == OSD_OP_SEC_WRITE || op->req.hdr.opcode == OSD_OP_SEC_WRITE_STABLE) &&
            op->req.sec_rw.attr_len > 0)
        {
            if (!wr.write((uint8_t*)op->bitmap, op->req.sec_rw.attr_len, WR_GCM))
                return false;
        }
        else if (op->req.hdr.opcode == OSD_OP_SEC_READ_BMP && op->req.sec_read_bmp.len > 0)
        {
            if (!wr.write((uint8_t*)op->buf, (size_t)op->req.sec_read_bmp.len, WR_GCM))
                return false;
        }
    }
    // Operation data
    if (op_has_data_for_ssl(op))
    {
        for (int i = 0; i < cl->write_op->iov.count; i++)
        {
            auto & iov = cl->write_op->iov.buf[i];
            if (!wr.write((uint8_t*)iov.iov_base, iov.iov_len, WR_GCM))
                return false;
        }
    }
    else if (op_has_data_for_nonssl(op))
    {
        for (int i = 0; i < cl->write_op->iov.count; i++)
        {
            auto & iov = cl->write_op->iov.buf[i];
            if (!wr.write((uint8_t*)iov.iov_base, iov.iov_len, (op->enc ? WR_XTS : 0) | (cl->proto_csum_status == MSGR_CSUM_GCM ? WR_GCM : 0)))
                return false;
        }
    }
    if (cl->proto_csum_status == MSGR_CSUM_FULL ||
        cl->proto_csum_status == MSGR_CSUM_PAYLOAD && cl->write_op_pos > OSD_PACKET_SIZE)
    {
        cl->write_op->csum = XXH3_64bits_digest(cl->write_csum_state);
        if (!wr.write((uint8_t*)&cl->write_op->csum, 8, WR_GCM|WR_NO_CSUM))
            return false;
    }
    if (!wr.finish())
        return false;
    op_encrypt_free(cl);
    cl->write_op = NULL;
    cl->write_op_pos = 0;
    return true;
}