rlm_sql_unixodbc.c

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/*
 * sql_unixodbc.c       unixODBC rlm_sql driver
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 *
 * @copyright 2000,2006 The FreeRADIUS server project
 * @copyright 2000 Dmitri Ageev (d_ageev@ortcc.ru)
 */
RCSID("$Id: 91f9276d6f8a9cf58a6b9330b119516ac9352368 $")
USES_APPLE_DEPRECATED_API
 
#define LOG_PREFIX "sql - unixodbc"
 
#include <freeradius-devel/server/base.h>
#include <freeradius-devel/util/debug.h>
 
#include <sqltypes.h>
#include "rlm_sql.h"
#include "rlm_sql_trunk.h"
 
typedef struct {
        SQLHENV                 env;            /* Environment handle */
        SQLHDBC                 dbc;            /* Database connection handle */
        SQLHSTMT                stmt;           /* Statement handle */
        SQLSMALLINT             colcount;       /* Number of columns in last result */
        rlm_sql_row_t           row;            /* Results row */
        SQLLEN                  *ind;           /* Data length / NULL indicators */
        connection_t            *conn;          /* Generic connection structure for this connection */
        rlm_sql_config_t const  *config;        /* SQL instance configuration */
        SQLUSMALLINT            async_mode;     /* What Async mode does this driver support */
        fr_sql_query_t          *query_ctx;     /* Current query running on the connection */
        fr_timer_t              *read_ev;       /* Timer event for polling reading this connection */
        fr_timer_t              *write_ev;      /* Timer event for polling writing this connection */
        uint                    select_interval;        /* How frequently this connection gets polled for select queries */
        uint                    query_interval; /* How frequently this connection gets polled for other queries */
        uint                    poll_count;     /* How many polls have been done for the current query */
} rlm_sql_unixodbc_conn_t;
 
USES_APPLE_DEPRECATED_API
#include <sql.h>
#include <sqlext.h>
 
/** Checks the error code to determine if the connection needs to be re-esttablished
 *
 * @param ret Return code from a failed unixodbc call.
 * @param handle_type Type of ODBC handle
 * @param handle ODBC handle
 * @return
 *      - #RLM_SQL_OK on success.
 *      - #RLM_SQL_ALT_QUERY if alternate queries should be tried.
 *      - #RLM_SQL_RECONNECT if reconnect is needed.
 *      - #RLM_SQL_ERROR on error.
 */
static sql_rcode_t sql_check_error(SQLRETURN ret, SQLSMALLINT handle_type, SQLHANDLE handle)
{
        SQLCHAR         state[6];
        SQLCHAR         error[256];
        SQLINTEGER      errornum = 0;
        SQLSMALLINT     length = 255;
        int             res = RLM_SQL_ERROR;
 
        if (SQL_SUCCEEDED(ret)) return 0; /* on success, just return 0 */
 
        error[0] = state[0] = '\0';
 
        SQLGetDiagRec(handle_type, handle, 1, state, &errornum, error, sizeof(error), &length);
 
        if (state[0] == '0') {
                switch (state[1]) {
                /* SQLSTATE 01 class contains info and warning messages */
                case '1':
                        INFO("%s %s", state, error);
                        FALL_THROUGH;
                case '0':               /* SQLSTATE 00 class means success */
                        res = RLM_SQL_OK;
                        break;
 
                /* SQLSTATE 08 class describes various connection errors */
                case '8':
                        ERROR("SQL down %s %s", state, error);
                        res = RLM_SQL_RECONNECT;
                        break;
 
                /* any other SQLSTATE means error */
                default:
                        ERROR("%s %s", state, error);
                        break;
                }
        } else {
                /* SQLSTATE 23000 is "Integrity constraint violation" - such as duplicate key */
                if (strcmp((char const *)state, "23000") == 0) {
                        res = RLM_SQL_ALT_QUERY;
                } else {
                        ERROR("%s %s", state, error);
                }
        }
 
        return res;
}
 
static void _sql_connection_close(UNUSED fr_event_list_t *el, void *h, UNUSED void *uctx)
{
        rlm_sql_unixodbc_conn_t *c = talloc_get_type_abort(h, rlm_sql_unixodbc_conn_t);
 
        if (c->read_ev) fr_timer_delete(&c->read_ev);
        if (c->write_ev) fr_timer_delete(&c->write_ev);
 
        if (c->stmt) SQLFreeHandle(SQL_HANDLE_STMT, c->stmt);
 
        if (c->dbc) {
                SQLDisconnect(c->dbc);
                SQLFreeHandle(SQL_HANDLE_DBC, c->dbc);
        }
 
        if (c->env) SQLFreeHandle(SQL_HANDLE_ENV, c->env);
        talloc_free(h);
}
 
static connection_state_t sql_trunk_connection_init_stmt(rlm_sql_unixodbc_conn_t *c)
{
        char            buff[256], verbuf[10];
        SQLRETURN       ret;
        SQLULEN         timeout;
 
        SQLGetInfo(c->dbc, SQL_DRIVER_NAME, buff, sizeof(buff), NULL);
        SQLGetInfo(c->dbc, SQL_DRIVER_ODBC_VER, verbuf, sizeof(verbuf), NULL);
        SQLGetInfo(c->dbc, SQL_ASYNC_MODE, &c->async_mode, 0, NULL);
        switch(c->async_mode) {
        case SQL_AM_NONE:
                DEBUG2("Using driver %s, ODBC version %s.  Driver does not support async operations", buff, verbuf);
                break;
        case SQL_AM_CONNECTION:
                DEBUG2("Using driver %s, ODBC version %s.  Async operation is set per connection", buff, verbuf);
                ret = SQLSetConnectAttr(c->dbc, SQL_ATTR_ASYNC_ENABLE, (SQLPOINTER)SQL_ASYNC_ENABLE_ON, SQL_IS_UINTEGER);
                sql_check_error(ret, SQL_HANDLE_DBC, c->dbc);
                break;
        case SQL_AM_STATEMENT:
                DEBUG2("Using driver %s, ODBC version %s.  Async operation is set per statement", buff, verbuf);
                break;
        }
 
        /* Allocate the stmt handle */
        ret = SQLAllocHandle(SQL_HANDLE_STMT, c->dbc, &c->stmt);
        if (sql_check_error(ret, SQL_HANDLE_DBC, c->dbc)) {
                ERROR("Can't allocate the stmt");
                _sql_connection_close(NULL, c, NULL);
                return CONNECTION_STATE_FAILED;
        }
        if (c->async_mode == SQL_AM_STATEMENT) {
                ret = SQLSetStmtAttr(c->stmt, SQL_ATTR_ASYNC_ENABLE, (SQLPOINTER)SQL_ASYNC_ENABLE_ON, 0);
                sql_check_error(ret, SQL_HANDLE_STMT, c->stmt);
        }
 
        timeout = fr_time_delta_to_sec(c->config->query_timeout);
        SQLSetStmtAttr(c->stmt, SQL_ATTR_QUERY_TIMEOUT, (SQLPOINTER)timeout, SQL_IS_UINTEGER);
 
        return CONNECTION_STATE_CONNECTED;
}
 
static void sql_trunk_connection_init_poll(fr_timer_list_t *tl, UNUSED fr_time_t now, void *uctx)
{
        rlm_sql_unixodbc_conn_t *c = talloc_get_type_abort(uctx, rlm_sql_unixodbc_conn_t);
        SQLRETURN               ret;
 
        ret = SQLConnect(c->dbc,
                         UNCONST(SQLCHAR *, c->config->sql_server), strlen(c->config->sql_server),
                         UNCONST(SQLCHAR *, c->config->sql_login), strlen(c->config->sql_login),
                         UNCONST(SQLCHAR *, c->config->sql_password), strlen(c->config->sql_password));
 
        if (ret == SQL_STILL_EXECUTING) {
                if (fr_timer_in(c, tl, &c->read_ev, fr_time_delta_from_usec(c->query_interval),
                                false, sql_trunk_connection_init_poll, c) < 0) {
                        ERROR("Unable to insert polling event");
                        connection_signal_reconnect(c->conn, CONNECTION_FAILED);
                }
                return;
        }
 
        if (sql_check_error(ret, SQL_HANDLE_DBC, c->dbc)) {
                ERROR("Connection failed");
                connection_signal_reconnect(c->conn, CONNECTION_FAILED);
        }
 
        if (sql_trunk_connection_init_stmt(c) == CONNECTION_STATE_CONNECTED) connection_signal_connected(c->conn);
}
 
CC_NO_UBSAN(function) /* UBSAN: false positive - public vs private connection_t trips --fsanitize=function */
static connection_state_t _sql_connection_init(void **h, connection_t *conn, void *uctx)
{
        rlm_sql_t const         *sql = talloc_get_type_abort_const(uctx, rlm_sql_t);
        rlm_sql_config_t const  *config = &sql->config;
        rlm_sql_unixodbc_conn_t *c;
        SQLRETURN               ret;
        SQLULEN                 timeout = fr_time_delta_to_sec(sql->config.trunk_conf.conn_conf->connection_timeout);
 
        MEM(c = talloc_zero(conn, rlm_sql_unixodbc_conn_t));
        *c = (rlm_sql_unixodbc_conn_t) {
                .conn = conn,
                .config = config,
                .select_interval = 1000,        /* Default starting poll interval - 1ms*/
                .query_interval = 1000,
        };
 
        /* Allocate environment handle and register version */
        ret = SQLAllocHandle(SQL_HANDLE_ENV, SQL_NULL_HANDLE, &c->env);
        if (ret == SQL_ERROR) {
                ERROR("Can't allocate environment handle");
        error:
                _sql_connection_close(NULL, c, NULL);
                return CONNECTION_STATE_FAILED;
        }
 
        ret = SQLSetEnvAttr(c->env, SQL_ATTR_ODBC_VERSION, (void*)SQL_OV_ODBC3_80, 0);
        if (sql_check_error(ret, SQL_HANDLE_ENV, c->env)) {
                ERROR("Can't register ODBC version");
                goto error;
        }
 
        /* Allocate connection handle */
        ret = SQLAllocHandle(SQL_HANDLE_DBC, c->env, &c->dbc);
        if (sql_check_error(ret, SQL_HANDLE_ENV, c->env)) {
                ERROR("Can't allocate connection handle");
                goto error;
        }
 
        /*
         *      Set the login / connection timeout
         *
         *      Note SQLSetConnectionAttr and SQLSetStmtAttr have an insane parameter passing
         *      model.  The 3rd parameter can be an integer, or a pointer to a string
         *      so integers get cast to pointers to match the function signature.
         */
        SQLSetConnectAttr(c->dbc, SQL_ATTR_LOGIN_TIMEOUT, (SQLPOINTER)timeout, SQL_IS_UINTEGER);
        SQLSetConnectAttr(c->dbc, SQL_ATTR_CONNECTION_TIMEOUT, (SQLPOINTER)timeout, SQL_IS_UINTEGER);
 
        /* Set the connection handle to Async */
        SQLSetConnectAttr(c->dbc, SQL_ATTR_ASYNC_DBC_FUNCTIONS_ENABLE, (SQLPOINTER)SQL_ASYNC_DBC_ENABLE_ON, SQL_IS_UINTEGER);
 
        /* Connect to the datasource */
        ret = SQLConnect(c->dbc,
                         UNCONST(SQLCHAR *, config->sql_server), strlen(config->sql_server),
                         UNCONST(SQLCHAR *, config->sql_login), strlen(config->sql_login),
                         UNCONST(SQLCHAR *, config->sql_password), strlen(config->sql_password));
 
        if (ret == SQL_STILL_EXECUTING) {
                if (fr_timer_in(c, conn->el->tl, &c->read_ev, fr_time_delta_from_usec(c->query_interval),
                                false, sql_trunk_connection_init_poll, c) < 0) {
                        ERROR("Unable to insert polling event");
                        goto error;
                }
                *h = c;
                return CONNECTION_STATE_CONNECTING;
        }
 
        if (sql_check_error(ret, SQL_HANDLE_DBC, c->dbc)) {
                ERROR("Connection failed");
                goto error;
        }
 
        *h = c;
        return sql_trunk_connection_init_stmt(c);
}
 
SQL_TRUNK_CONNECTION_ALLOC
 
CC_NO_UBSAN(function) /* UBSAN: false positive - public vs private connection_t trips --fsanitize=function */
static void sql_trunk_request_mux(UNUSED fr_event_list_t *el, trunk_connection_t *tconn, connection_t *conn, UNUSED void *uctx)
{
        rlm_sql_unixodbc_conn_t *sql_conn = talloc_get_type_abort(conn->h, rlm_sql_unixodbc_conn_t);
        request_t               *request;
        trunk_request_t         *treq;
        fr_sql_query_t          *query_ctx;
        SQLRETURN               ret;
 
        if (trunk_connection_pop_request(&treq, tconn) != 0) return;
        if (!treq) return;
 
        query_ctx = talloc_get_type_abort(treq->preq, fr_sql_query_t);
        request = query_ctx->request;
 
        switch(query_ctx->status) {
        case SQL_QUERY_PREPARED:
                ROPTIONAL(RDEBUG2, DEBUG2, "Executing query: %s", query_ctx->query_str);
                ret = SQLExecDirect(sql_conn->stmt, UNCONST(SQLCHAR *, query_ctx->query_str), strlen(query_ctx->query_str));
                query_ctx->tconn = tconn;
 
                if (ret == SQL_STILL_EXECUTING) {
                        ROPTIONAL(RDEBUG3, DEBUG3, "Awaiting response");
                        query_ctx->status = SQL_QUERY_SUBMITTED;
                        sql_conn->query_ctx = query_ctx;
                        sql_conn->poll_count = 0;
                        trunk_request_signal_sent(treq);
                        return;
                }
 
                query_ctx->rcode = sql_check_error(ret, SQL_HANDLE_STMT, sql_conn->stmt);
                switch(query_ctx->rcode) {
                case RLM_SQL_OK:
                case RLM_SQL_ALT_QUERY:
                        break;
 
                default:
                        query_ctx->status = SQL_QUERY_FAILED;
                        trunk_request_signal_fail(treq);
                        if (query_ctx->rcode == RLM_SQL_RECONNECT) connection_signal_reconnect(conn, CONNECTION_FAILED);
                        return;
                }
                query_ctx->status = SQL_QUERY_RETURNED;
                break;
 
        default:
                return;
        }
 
        ROPTIONAL(RDEBUG3, DEBUG3, "Got immediate response");
        trunk_request_signal_reapable(treq);
        if (request) unlang_interpret_mark_runnable(request);
}
 
CC_NO_UBSAN(function) /* UBSAN: false positive - public vs private connection_t trips --fsanitize=function */
static void sql_request_cancel(connection_t *conn, void *preq, trunk_cancel_reason_t reason,
                                UNUSED void *uctx)
{
        fr_sql_query_t          *query_ctx = talloc_get_type_abort(preq, fr_sql_query_t);
        rlm_sql_unixodbc_conn_t *sql_conn = talloc_get_type_abort(conn->h, rlm_sql_unixodbc_conn_t);
 
        if (!query_ctx->treq) return;
        if (reason != TRUNK_CANCEL_REASON_SIGNAL) return;
        if (sql_conn->query_ctx == query_ctx) sql_conn->query_ctx = NULL;
}
 
CC_NO_UBSAN(function) /* UBSAN: false positive - public vs private connection_t trips --fsanitize=function */
static void sql_request_cancel_mux(UNUSED fr_event_list_t *el, trunk_connection_t *tconn,
                                   connection_t *conn, UNUSED void *uctx)
{
        trunk_request_t         *treq;
        rlm_sql_unixodbc_conn_t *sql_conn = talloc_get_type_abort(conn->h, rlm_sql_unixodbc_conn_t);
        SQLRETURN               ret;
        fr_sql_query_t          *query_ctx;
 
        if ((trunk_connection_pop_cancellation(&treq, tconn)) != 0) return;
        if (!treq) return;
 
        query_ctx = talloc_get_type_abort(treq->preq, fr_sql_query_t);
        ret = SQLCancel(sql_conn->stmt);
        query_ctx->status = SQL_QUERY_CANCELLED;
        if (ret == SQL_STILL_EXECUTING) {
                trunk_request_signal_cancel_sent(treq);
                return;
        }
        trunk_request_signal_cancel_complete(treq);
}
 
static void sql_trunk_connection_read_poll(fr_timer_list_t *tl, UNUSED fr_time_t now, void *uctx)
{
        rlm_sql_unixodbc_conn_t *c = talloc_get_type_abort(uctx, rlm_sql_unixodbc_conn_t);
        fr_sql_query_t          *query_ctx = c->query_ctx;
        SQLRETURN               ret;
        trunk_request_t         *treq = query_ctx->treq;
        request_t               *request = query_ctx->request;
 
        switch (query_ctx->status) {
        case SQL_QUERY_SUBMITTED:
                ret = SQLExecDirect(c->stmt, UNCONST(SQLCHAR *, query_ctx->query_str), strlen(query_ctx->query_str));
                c->poll_count++;
                /* Back off the poll interval, up to half the query timeout */
                if (c->poll_count > 2) {
                        if (query_ctx->type == SQL_QUERY_SELECT) {
                                if (c->select_interval < fr_time_delta_to_usec(c->config->query_timeout)/2) c->select_interval += 100;
                        } else {
                                if (c->query_interval < fr_time_delta_to_usec(c->config->query_timeout)/2) c->query_interval += 100;
                        }
                }
                if (ret == SQL_STILL_EXECUTING) {
                        ROPTIONAL(RDEBUG3, DEBUG3, "Still awaiting response");
                        if (fr_timer_in(c, tl, &c->read_ev,
                                        fr_time_delta_from_usec(query_ctx->type == SQL_QUERY_SELECT ? c->select_interval : c->query_interval),
                                        false, sql_trunk_connection_read_poll, c) < 0) {
                                ERROR("Unable to insert polling event");
                        }
                        return;
                }
 
                query_ctx->rcode = sql_check_error(ret, SQL_HANDLE_STMT, c->stmt);
                switch(query_ctx->rcode) {
                case RLM_SQL_OK:
                case RLM_SQL_ALT_QUERY:
                        /* If we only polled once, reduce the interval*/
                        if (c->poll_count == 1) {
                                if (query_ctx->type == SQL_QUERY_SELECT) {
                                        c->select_interval /= 2;
                                } else {
                                        c->query_interval /= 2;
                                }
                        }
                        break;
 
                default:
                        query_ctx->status = SQL_QUERY_FAILED;
                        trunk_request_signal_fail(treq);
                        if (query_ctx->rcode == RLM_SQL_RECONNECT) connection_signal_reconnect(c->conn, CONNECTION_FAILED);
                        return;
                }
                break;
 
        case SQL_QUERY_CANCELLED:
                ret = SQLCancel(c->stmt);
                if (ret == SQL_STILL_EXECUTING) {
                        ROPTIONAL(RDEBUG3, DEBUG3, "Still awaiting response");
                        if (fr_timer_in(c, tl, &c->read_ev, fr_time_delta_from_usec(query_ctx->type == SQL_QUERY_SELECT ? c->select_interval : c->query_interval),
                                        false, sql_trunk_connection_read_poll, c) < 0) {
                                ERROR("Unable to insert polling event");
                        }
                        return;
                }
                trunk_request_signal_cancel_complete(treq);
                return;
 
        default:
                return;
        }
 
        if (request) unlang_interpret_mark_runnable(request);
}
 
static void sql_trunk_connection_write_poll(UNUSED fr_timer_list_t *tl, UNUSED fr_time_t now, void *uctx)
{
        trunk_connection_t      *tconn = talloc_get_type_abort(uctx, trunk_connection_t);
 
        trunk_connection_signal_writable(tconn);
}
 
/*
 *      UnixODBC doesn't support event driven async, so in this case
 *      we have to resort to polling.
 *
 *      This "notify" callback sets up the appropriate polling events.
 */
CC_NO_UBSAN(function) /* UBSAN: false positive - public vs private connection_t trips --fsanitize=function */
static void sql_trunk_connection_notify(UNUSED trunk_connection_t *tconn, connection_t *conn, fr_event_list_t *el,
                                        trunk_connection_event_t notify_on, UNUSED void *uctx)
{
        rlm_sql_unixodbc_conn_t *c = talloc_get_type_abort(conn->h, rlm_sql_unixodbc_conn_t);
        fr_sql_query_t          *query_ctx = c->query_ctx;
        uint                    poll_interval = (query_ctx && query_ctx->type != SQL_QUERY_SELECT) ? c->query_interval : c->select_interval;
        switch (notify_on) {
        case TRUNK_CONN_EVENT_NONE:
                if (c->read_ev) fr_timer_delete(&c->read_ev);
                if (c->write_ev) fr_timer_delete(&c->write_ev);
                return;
 
        case TRUNK_CONN_EVENT_BOTH:
        case TRUNK_CONN_EVENT_READ:
                if (c->query_ctx) {
                        if (fr_timer_in(c, el->tl, &c->read_ev, fr_time_delta_from_usec(poll_interval),
                                        false, sql_trunk_connection_read_poll, c) < 0) {
                                ERROR("Unable to insert polling event");
                        }
                }
                if (notify_on == TRUNK_CONN_EVENT_READ) return;
 
                FALL_THROUGH;
 
        case TRUNK_CONN_EVENT_WRITE:
                if (fr_timer_in(c, el->tl, &c->write_ev, fr_time_delta_from_usec(0),
                                false, sql_trunk_connection_write_poll, tconn) < 0) {
                        ERROR("Unable to insert polling event");
                }
                return;
        }
}
 
SQL_QUERY_FAIL
SQL_QUERY_RESUME
 
static unlang_action_t sql_select_query_resume(rlm_rcode_t *p_result, UNUSED int *priority, UNUSED request_t *request, void *uctx)
{
        fr_sql_query_t          *query_ctx = talloc_get_type_abort(uctx, fr_sql_query_t);
        rlm_sql_unixodbc_conn_t *conn = talloc_get_type_abort(query_ctx->tconn->conn->h, rlm_sql_unixodbc_conn_t);
        SQLINTEGER              i;
        SQLLEN                  len;
        SQLRETURN               ret = SQL_STILL_EXECUTING;
 
        if (query_ctx->rcode != RLM_SQL_OK) RETURN_MODULE_FAIL;
 
        while (ret == SQL_STILL_EXECUTING) {
                ret = SQLNumResultCols(conn->stmt, &conn->colcount);
        }
        if (sql_check_error(ret, SQL_HANDLE_STMT, conn->stmt)) {
                query_ctx->rcode = RLM_SQL_ERROR;
                RETURN_MODULE_FAIL;
        }
 
        /* Reserving memory for result */
        conn->row = talloc_zero_array(conn, char *, conn->colcount + 1); /* Space for pointers */
        conn->ind = talloc_zero_array(conn, SQLLEN, conn->colcount); /* Space for indicators */
 
        for (i = 1; i <= conn->colcount; i++) {
                len = 0;
                /* SQLColAttribute can in theory run Async */
                while (SQLColAttribute(conn->stmt, (SQLUSMALLINT) i, SQL_DESC_LENGTH, NULL, 0, NULL, &len) == SQL_STILL_EXECUTING);
                conn->row[i - 1] = talloc_array(conn->row, char, ++len);
                SQLBindCol(conn->stmt, i, SQL_C_CHAR, (SQLCHAR *)conn->row[i - 1], len, &conn->ind[i - 1]);
        }
 
        RETURN_MODULE_OK;
}
 
static sql_rcode_t sql_fields(char const **out[], fr_sql_query_t *query_ctx, UNUSED rlm_sql_config_t const *config)
{
        rlm_sql_unixodbc_conn_t *conn = talloc_get_type_abort(query_ctx->tconn->conn->h, rlm_sql_unixodbc_conn_t);
        SQLSMALLINT             len, i;
        SQLRETURN               ret;
        char const              **names;
        char                    field[128];
 
        if (conn->colcount == 0) return RLM_SQL_ERROR;
 
        MEM(names = talloc_array(query_ctx, char const *, conn->colcount));
 
        for (i = 0; i < conn->colcount; i++) {
                char *p;
                ret = SQL_STILL_EXECUTING;
                while (ret == SQL_STILL_EXECUTING) {
                        ret = SQLColAttribute(conn->stmt, i + 1, SQL_DESC_NAME,
                                              field, sizeof(field), &len, NULL);
                }
                switch (ret) {
                case SQL_INVALID_HANDLE:
                case SQL_ERROR:
                        ERROR("Failed retrieving field name at index %i", i);
                        sql_check_error(ret, SQL_HANDLE_STMT, conn->stmt);
                        talloc_free(names);
                        return RLM_SQL_ERROR;
 
                default:
                        break;
                }
 
                MEM(p = talloc_array(names, char, (size_t)len + 1));
                strlcpy(p, field, (size_t)len + 1);
                names[i] = p;
        }
        *out = names;
 
        return RLM_SQL_OK;
}
 
static unlang_action_t sql_fetch_row(rlm_rcode_t *p_result, UNUSED int *priority, UNUSED request_t *request, void *uctx)
{
        fr_sql_query_t          *query_ctx = talloc_get_type_abort(uctx, fr_sql_query_t);
        rlm_sql_unixodbc_conn_t *conn = talloc_get_type_abort(query_ctx->tconn->conn->h, rlm_sql_unixodbc_conn_t);
        SQLRETURN               ret = SQL_STILL_EXECUTING;
        SQLINTEGER              i;
 
        query_ctx->row = NULL;
 
        while (ret == SQL_STILL_EXECUTING) {
                ret = SQLFetch(conn->stmt);
        }
        if (ret == SQL_NO_DATA_FOUND) {
                query_ctx->rcode = RLM_SQL_NO_MORE_ROWS;
                RETURN_MODULE_OK;
        }
 
        query_ctx->rcode = sql_check_error(ret, SQL_HANDLE_STMT, conn->stmt);
        if (query_ctx->rcode != RLM_SQL_OK) RETURN_MODULE_FAIL;
 
        /*
         *      If the field is NULL, then SQLFetch doesn't touch pointer, so set it here
         */
        for (i = 0; i < conn->colcount; i++) {
                if (conn->ind[i] == SQL_NULL_DATA) conn->row[i] = NULL;
        }
 
        query_ctx->row = conn->row;
 
        query_ctx->rcode = RLM_SQL_OK;
        RETURN_MODULE_OK;
}
 
static sql_rcode_t sql_free_result(fr_sql_query_t *query_ctx, UNUSED rlm_sql_config_t const *config)
{
        rlm_sql_unixodbc_conn_t *conn = query_ctx->tconn->conn->h;
 
        TALLOC_FREE(conn->row);
        TALLOC_FREE(conn->ind);
        conn->colcount = 0;
 
        return RLM_SQL_OK;
}
 
static sql_rcode_t sql_finish_query(fr_sql_query_t *query_ctx, UNUSED rlm_sql_config_t const *config)
{
        rlm_sql_unixodbc_conn_t *conn;
 
        /*
         *      If the query is not in a state which would return results, then do nothing.
         */
        if (query_ctx->treq && !(query_ctx->treq->state &
            (TRUNK_REQUEST_STATE_SENT | TRUNK_REQUEST_STATE_REAPABLE | TRUNK_REQUEST_STATE_COMPLETE))) return RLM_SQL_OK;
 
        /*
         *      If the connection doesn't exist there's nothing to do
         */
        if (!query_ctx->tconn || !query_ctx->tconn->conn || !query_ctx->tconn->conn->h) return RLM_SQL_ERROR;
 
        conn = talloc_get_type_abort(query_ctx->tconn->conn->h, rlm_sql_unixodbc_conn_t);
 
        TALLOC_FREE(conn->row);
        conn->colcount = 0;
        conn->query_ctx = NULL;
 
        /*
         *      SQL_CLOSE - The cursor (if any) associated with the statement
         *      handle (StatementHandle) is closed and all pending results are
         *      discarded. The application can reopen the cursor by calling
         *      SQLExecute() with the same or different values in the
         *      application variables (if any) that are bound to StatementHandle.
         *      If no cursor has been associated with the statement handle,
         *      this option has no effect (no warning or error is generated).
         *
         *      So, this call does NOT free the statement at all, it merely
         *      resets it for the next call. This is terrible terrible naming.
         */
        SQLFreeStmt(conn->stmt, SQL_CLOSE);
 
        return RLM_SQL_OK;
}
 
/** Retrieves any errors associated with the query context
 *
 * @note Caller will free any memory allocated in ctx.
 *
 * @param ctx to allocate temporary error buffers in.
 * @param out Array of #sql_log_entry_t to fill.
 * @param outlen Length of out array.
 * @param query_ctx Query context to retrieve error for.
 * @return number of errors written to the #sql_log_entry_t array.
 */
static size_t sql_error(TALLOC_CTX *ctx, sql_log_entry_t out[], NDEBUG_UNUSED size_t outlen,
                        fr_sql_query_t *query_ctx)
{
        rlm_sql_unixodbc_conn_t *conn = query_ctx->tconn->conn->h;
        SQLCHAR                 state[256];
        SQLCHAR                 errbuff[256];
        SQLINTEGER              errnum = 0;
        SQLSMALLINT             length = 255;
        size_t                  i = 0;
 
        fr_assert(outlen > 2);
 
        /*
         *      Depending on which handles exist at the time of calling there
         *      may be 1, 2 or 3 handles to check errors on.
         */
        errbuff[0] = state[0] = '\0';
        SQLGetDiagRec(SQL_HANDLE_ENV, conn->env, 1, state, &errnum, errbuff, sizeof(errbuff), &length);
        if (errnum != 0) {
                out[i].type = L_ERR;
                out[i].msg = talloc_typed_asprintf(ctx, "%s: %s", state, errbuff);
                i++;
        }
        if (conn->dbc == SQL_NULL_HANDLE) return i;
 
        SQLGetDiagRec(SQL_HANDLE_DBC, conn->dbc, 1, state, &errnum, errbuff, sizeof(errbuff), &length);
        if (errnum != 0) {
                out[i].type = L_ERR;
                out[i].msg = talloc_typed_asprintf(ctx, "%s: %s", state, errbuff);
                i++;
        }
        if (conn->stmt == SQL_NULL_HANDLE) return i;
 
        SQLGetDiagRec(SQL_HANDLE_STMT, conn->stmt, 1, state, &errnum, errbuff, sizeof(errbuff), &length);
        if (errnum != 0) {
                out[i].type = L_ERR;
                out[i].msg = talloc_typed_asprintf(ctx, "%s: %s", state, errbuff);
                i++;
        }
 
        return i;
}
 
/*************************************************************************
 *
 *      Function: sql_affected_rows
 *
 *      Purpose: Return the number of rows affected by the query (update,
 *             or insert)
 *
 *************************************************************************/
static int sql_affected_rows(fr_sql_query_t *query_ctx, UNUSED rlm_sql_config_t const *config)
{
        rlm_sql_unixodbc_conn_t *conn = query_ctx->tconn->conn->h;
        SQLRETURN               ret;
        SQLLEN                  affected_rows;
 
        ret = SQLRowCount(conn->stmt, &affected_rows);
        if (sql_check_error(ret, SQL_HANDLE_STMT, conn->stmt)) return -1;
 
        return affected_rows;
}
 
 
/* Exported to rlm_sql */
extern rlm_sql_driver_t rlm_sql_unixodbc;
rlm_sql_driver_t rlm_sql_unixodbc = {
        .common = {
                .magic                          = MODULE_MAGIC_INIT,
                .name                           = "sql_unixodbc"
        },
        .flags                          = RLM_SQL_RCODE_FLAGS_ALT_QUERY,
        .sql_query_resume               = sql_query_resume,
        .sql_select_query_resume        = sql_select_query_resume,
        .sql_affected_rows              = sql_affected_rows,
        .sql_fields                     = sql_fields,
        .sql_fetch_row                  = sql_fetch_row,
        .sql_free_result                = sql_free_result,
        .sql_error                      = sql_error,
        .sql_finish_query               = sql_finish_query,
        .sql_finish_select_query        = sql_finish_query,
        .trunk_io_funcs = {
                .connection_alloc       = sql_trunk_connection_alloc,
                .connection_notify      = sql_trunk_connection_notify,
                .request_mux            = sql_trunk_request_mux,
                .request_cancel_mux     = sql_request_cancel_mux,
                .request_cancel         = sql_request_cancel,
                .request_fail           = sql_request_fail,
        }
};