iscsi-login.c

这个linux源代码是很全面的~基本完整了~使用c编译的~由于时间问题我没有亲自测试~但就算用来做参考资料也是非常好的

                        return 0;
                    }
                }
                else if (iscsi_find_key_value("TargetPortalGroupTag", text, end, &value, &value_end)) {
                    /* We should have already obtained this via discovery. 
                     * We've already picked an isid, so the most we can do is confirm we reached
                     * the portal group we were expecting to.
                     */
                    int tag = iscsi_strtoul(value, NULL, 0);
                    if (session->portal_group_tag >= 0) {
                        if (tag != session->portal_group_tag) {
                            logmsg(AS_ERROR, "session %p portal group tag mismatch, expected %u, actual %u\n",
                                   session, session->portal_group_tag, tag);
                            return 0;
                        }
                    }
                    else {
                        /* we now know the tag */
                        session->portal_group_tag = tag;
                    }
                    text = value_end;
                } 
                else if (iscsi_find_key_value("InitialR2T", text, end, &value, &value_end)) {
                    if (value && iscsi_strcmp(value, "Yes") == 0)
                        session->InitialR2T = 1;
                    else
                        session->InitialR2T = 0;
                    text = value_end;
                } 
                else if (iscsi_find_key_value("ImmediateData", text, end, &value, &value_end)) {
                    if (value && iscsi_strcmp(value, "Yes") == 0)
                        session->ImmediateData = 1;
                    else
                        session->ImmediateData = 0;
                    text = value_end;
                } 
                else if (iscsi_find_key_value("MaxRecvDataSegmentLength", text, end, &value, &value_end)) {
                    /* FIXME: no octal */
                    session->MaxXmitDataSegmentLength = iscsi_strtoul(value, NULL, 0);
                    text = value_end;
                } 
                else if (iscsi_find_key_value("FirstBurstLength", text, end, &value, &value_end)) {
                    /* FIXME: no octal */
                    session->FirstBurstLength = iscsi_strtoul(value, NULL, 0);
                    text = value_end;
                } 
                else if (iscsi_find_key_value("MaxBurstLength", text, end, &value, &value_end)) {
                    /* we don't really care, since it's a limit on the target's R2Ts, but record it anwyay */
                    /* FIXME: no octal, and draft16 says we MUST NOT send more than MaxBurstLength */
                    session->MaxBurstLength = iscsi_strtoul(value, NULL, 0);
                    text = value_end;
                } 
                else if (iscsi_find_key_value("HeaderDigest", text, end, &value, &value_end)) {
                    if (iscsi_strcmp(value, "None")) {
                        logmsg(AS_ERROR, "session %p can't accept %s\n", session, text);
                        return 0;
                    }
                    text = value_end;
                }
                else if (iscsi_find_key_value("DataDigest", text, end, &value, &value_end)) {
                    if (iscsi_strcmp(value, "None")) {
                        logmsg(AS_ERROR, "session %p can't accept %s\n", session, text);
                        return 0;
                    }
                    text = value_end;
                }
                else if (iscsi_find_key_value("DefaultTime2Wait", text, end, &value, &value_end)) {
                    session->DefaultTime2Wait = iscsi_strtoul(value, NULL, 0);
                    text = value_end;
                } 
                else if (iscsi_find_key_value("DefaultTime2Retain", text, end, &value, &value_end)) {
                    session->DefaultTime2Retain = iscsi_strtoul(value, NULL, 0);
                    text = value_end;
                } 
                else if (iscsi_find_key_value("OFMarker", text, end, &value, &value_end)) {
                    /* result function is AND, target must honor our No */
                    text = value_end;
                } 
                else if (iscsi_find_key_value("OFMarkInt", text, end, &value, &value_end)) {
                    /* we don't do markers, so we don't care */
                    text = value_end;
                } 
                else if (iscsi_find_key_value("IFMarker", text, end, &value, &value_end)) {
                    /* result function is AND, target must honor our No */
                    text = value_end;
                } 
                else if (iscsi_find_key_value("IFMarkInt", text, end, &value, &value_end)) {
                    /* we don't do markers, so we don't care */
                    text = value_end;
                } 
                else if (iscsi_find_key_value("DataPDUInOrder", text, end, &value, &value_end)) {
                    if (value && iscsi_strcmp(value, "Yes") == 0)
                        session->DataPDUInOrder = 1;
                    else
                        session->DataPDUInOrder = 0;
                    text = value_end;
                } 
                else if (iscsi_find_key_value("DataSequenceInOrder", text, end, &value, &value_end)) {
                    if (value && iscsi_strcmp(value, "Yes") == 0)
                        session->DataSequenceInOrder = 1;
                    else
                        session->DataSequenceInOrder = 0;
                    text = value_end;
                } 
                else if (iscsi_find_key_value("MaxOutstandingR2T", text, end, &value, &value_end)) {
                    if (iscsi_strcmp(value, "1")) {
                        logmsg(AS_ERROR, "session %p can't accept MaxOutstandingR2T %s\n", session, value);
                        return 0;
                    }
                    text = value_end;
                } 
                else if (iscsi_find_key_value("MaxConnections", text, end, &value, &value_end)) {
                    if (iscsi_strcmp(value, "1")) {
                        logmsg(AS_ERROR, "session %p can't accept MaxConnections %s\n", session, value);
                        return 0;
                    }
                    text = value_end;
                } 
                else if (iscsi_find_key_value("ErrorRecoveryLevel", text, end, &value, &value_end)) {
                    if (iscsi_strcmp(value, "0")) {
                        logmsg(AS_ERROR, "session %p can't accept ErrorRecovery %s\n", session, value);
                        return 0;
                    }
                    text = value_end;
                } 
                else if (iscsi_find_key_value("X-com.cisco.protocol", text, end, &value, &value_end)) {
                    if (iscsi_strcmp(value, "NotUnderstood") && iscsi_strcmp(value, "draft16")) {
                        /* if we didn't get a compatible protocol, fail */
                        logmsg(AS_ERROR, "can't accept protocol %s\n", value);
                        return 0;
                    }
                    text = value_end;
                }
                else if (iscsi_find_key_value("X-com.cisco.PingTimeout", text, end, &value, &value_end)) {
                    /* don't care */
                    text = value_end;
                } 
                else {
                    /* FIXME: we may want to ignore X- keys sent by
                     * the target, but that would require us to have
                     * another PDU buffer so that we can generate a
                     * response while we still know what keys we
                     * received, so that we can reply with a
                     * NotUnderstood response.  For now, reject logins
                     * with keys we don't understand.  Another option is
                     * to silently ignore them, and see if the target has
                     * a problem with that.  The danger there is we may
                     * get caught in an infinite loop where we send an empty
                     * PDU requesting a phase transition, and the target
                     * keeps sending an empty PDU denying a phase transition
                     * (because we haven't replied to it's key yet).
                     */
                    logmsg(AS_ERROR, "failed to recognize text %s\n", text);
                    return 0;
                }
                break;
            }
            default:
                return 0;
        }
    }

    if (session->current_phase == ISCSI_SECURITY_NEGOTIATION_PHASE) {
        switch (iscsiAuthClientRecvEnd(session->auth_client, null_callback, NULL, NULL)) {
            default:
            case iscsiAuthStatusNoError: /* treat this as an error, since we should get a different code */
            case iscsiAuthStatusError:
                logmsg(AS_ERROR, "session %p error authenticating with target %s\n", 
                       session, session->TargetName);
                return 0;

            case iscsiAuthStatusInProgress:
                /* this should only occur if we were authenticating the target,
                 * which we don't do yet, so treat this as an error.
                 */
                logmsg(AS_ERROR, "session %p error authenticating target %s\n", session, session->TargetName);
                return 0;
                
            case iscsiAuthStatusContinue:
                /* continue sending PDUs */
                break;

            case iscsiAuthStatusPass:
                logmsg(AS_INFO, "session %p authenticated by target %s\n", 
                       session, session->TargetName);
                break;
            case iscsiAuthStatusFail:
                logmsg(AS_ERROR, "session %p failed authentication with target %s\n", 
                       session, session->TargetName);
                return 0;
        }
    }

    /* record some of the PDU fields for later use */
    session->tsid = iscsi_ntohs(login_rsp_pdu->tsid);
    session->ExpCmdSn = iscsi_ntohl(login_rsp_pdu->expcmdsn);
    session->MaxCmdSn = iscsi_ntohl(login_rsp_pdu->maxcmdsn);
    if (login_rsp_pdu->status_class == STATUS_CLASS_SUCCESS)
        session->ExpStatSn = iscsi_ntohl(login_rsp_pdu->statsn) + 1;

    if (login_rsp_pdu->tbit) {
        /* advance to the next phase */
        session->partial_response = 0;
        session->current_phase = login_rsp_pdu->next;
    }
    else {
        /* we got a partial response, don't advance, more negotiation to do */
        session->partial_response = 1;
    }

    return 1;
}

int iscsi_make_text_pdu(iscsi_session_t *session, struct IscsiHdr *pdu, char *data, int max_data_length)
{
    struct IscsiTextHdr *text_pdu = (struct IscsiTextHdr *)pdu;

    /* initialize the PDU header */
    memset(text_pdu, 0, sizeof(*text_pdu));

    text_pdu->opcode = ISCSI_OP_TEXT_CMD;
    text_pdu->itt = iscsi_htonl(session->itt);
    text_pdu->ttt = RSVD_TASK_TAG;
    text_pdu->cmdsn = iscsi_htonl(session->CmdSn++); 
    text_pdu->expstatsn = iscsi_htonl(session->ExpStatSn);

    return 1;
}


int iscsi_make_login_pdu(iscsi_session_t *session, struct IscsiHdr *pdu, char *data, int max_data_length)
{
    int tbit = 0;
    char value[iscsiAuthStringMaxLength];
    struct IscsiLoginHdr *login_pdu = (struct IscsiLoginHdr *)pdu;

    /* initialize the PDU header */
    memset(login_pdu, 0, sizeof(*login_pdu));
    login_pdu->opcode = ISCSI_OP_LOGIN_CMD | ISCSI_OP_IMMEDIATE;
    login_pdu->cid = 0;
    memcpy(login_pdu->isid, session->isid, sizeof(session->isid));
    login_pdu->tsid = 0;
    login_pdu->cmdsn = iscsi_htonl(session->CmdSn); /* don't increment on immediate */
    
    login_pdu->min_version = ISCSI_DRAFT16_VERSION;
    login_pdu->max_version = ISCSI_DRAFT16_VERSION;

    /* we have to send 0 until full-feature phase */
    login_pdu->expstatsn = 0; /* iscsi_htonl(session->ExpStatSn); */

    /* the very first Login PDU has some additional requirements, 
     * and we need to decide what phase to start in.
     */
    if (session->current_phase == ISCSI_INITIAL_LOGIN_PHASE) {
        if (session->InitiatorName && session->InitiatorName[0]) {
            if (!iscsi_add_text(session, pdu, data, max_data_length, "InitiatorName", session->InitiatorName))
                return 0;
        }
        else {
            logmsg(AS_ERROR, "InitiatorName is required on the first Login PDU\n");
            return 0;
        }
        if (session->InitiatorAlias && session->InitiatorAlias[0]) {
            if (!iscsi_add_text(session, pdu, data, max_data_length, "InitiatorAlias", session->InitiatorAlias))
                return 0;
        }
        
        if (session->TargetName[0] != '\0') {
            if (!iscsi_add_text(session, pdu, data, max_data_length, "TargetName", session->TargetName))
                return 0;
        }

        if (!iscsi_add_text(session, pdu, data, max_data_length, "SessionType",
                                  (session->type == ISCSI_SESSION_TYPE_DISCOVERY) ? "Discovery" : "Normal"))
            return 0;
        
        if (session->auth_client) {
            /* we're prepared to do authentication */
            session->current_phase = session->next_phase = ISCSI_SECURITY_NEGOTIATION_PHASE;
        }
        else {
            /* can't do any authentication, skip that phase */
            session->current_phase = session->next_phase = ISCSI_OP_PARMS_NEGOTIATION_PHASE;
        }        
    }