cf_parse.c

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/*
 *   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
 */
 
/**
 * $Id: 643228fb76297686d6d0fee7148e3dc8a45c1805 $
 * @file cf_parse.c
 * @brief Convert internal format configuration values into native C types.
 *
 * @copyright 2017 Arran Cudbard-Bell (a.cudbardb@freeradius.org)
 * @copyright 2000,2006 The FreeRADIUS server project
 * @copyright 2000 Miquel van Smoorenburg (miquels@cistron.nl)
 * @copyright 2000 Alan DeKok (aland@freeradius.org)
 */
RCSID("$Id: 643228fb76297686d6d0fee7148e3dc8a45c1805 $")
 
#include <string.h>
 
#include <freeradius-devel/server/cf_file.h>
#include <freeradius-devel/server/cf_parse.h>
#include <freeradius-devel/server/cf_priv.h>
#include <freeradius-devel/server/log.h>
#include <freeradius-devel/server/tmpl.h>
#include <freeradius-devel/server/virtual_servers.h>
#include <freeradius-devel/util/debug.h>
#include <freeradius-devel/util/inet.h>
#include <freeradius-devel/util/misc.h>
#include <freeradius-devel/util/perm.h>
#include <freeradius-devel/util/types.h>
 
static conf_parser_t conf_term = CONF_PARSER_TERMINATOR;
static char const parse_spaces[] = "                                                                                                                                                                                                                                              ";
 
#define PAIR_SPACE(_cs) ((_cs->depth + 1) * 2)
#define SECTION_SPACE(_cs) (_cs->depth * 2)
 
void cf_pair_debug_log(CONF_SECTION const *cs, CONF_PAIR *cp, conf_parser_t const *rule)
{
        char const      *value;
        char            *tmp = NULL;
        char const      *quote = "";
        bool            secret = (rule->flags & CONF_FLAG_SECRET);
        fr_type_t       type;
 
        if (cp->printed) return;
 
        /*
         *      tmpls are special, they just need to get printed as string
         */
        if (rule->flags & CONF_FLAG_TMPL) {
                type = FR_TYPE_STRING;
        } else {
                type = rule->type;
        }
 
        if (secret && (fr_debug_lvl < L_DBG_LVL_3)) {
                cf_log_debug(cs, "%.*s%s = <<< secret >>>", PAIR_SPACE(cs), parse_spaces, cp->attr);
                return;
        }
 
        /*
         *      Print the strings with the correct quotation character and escaping.
         */
        if (fr_type_is_string(type)) {
                value = tmp = fr_asprint(NULL, cp->value, talloc_array_length(cp->value) - 1, fr_token_quote[cp->rhs_quote]);
 
        } else {
                value = cf_pair_value(cp);
        }
 
        if (fr_type_is_quoted(type)) {
                switch (cf_pair_value_quote(cp)) {
                default:
                        break;
 
                case T_DOUBLE_QUOTED_STRING:
                        quote = "\"";
                        break;
 
                case T_SINGLE_QUOTED_STRING:
                        quote = "'";
                        break;
 
                case T_BACK_QUOTED_STRING:
                        quote = "`";
                        break;
 
                case T_SOLIDUS_QUOTED_STRING:
                        quote = "/";
                        break;
                }
        }
 
        cf_log_debug(cs, "%.*s%s = %s%s%s", PAIR_SPACE(cs), parse_spaces, cp->attr, quote, value, quote);
 
        talloc_free(tmp);
 
        cp->printed = true;
}
 
/** Parses a #CONF_PAIR into a boxed value
 *
 * @copybrief cf_pair_value
 * @see cf_pair_value
 *
 * @param[in] ctx       to allocate any dynamic buffers in.
 * @param[out] out      Where to write the parsed value.
 * @param[in] cp        to parse.
 * @param[in] rule      to parse to.  May contain flags.
 * @return
 *      - 0 on success.
 *      - -1 on failure.
 */
int cf_pair_to_value_box(TALLOC_CTX *ctx, fr_value_box_t *out, CONF_PAIR *cp, conf_parser_t const *rule)
{
        if (fr_value_box_from_str(ctx, out, rule->type, NULL, cp->value, talloc_array_length(cp->value) - 1, NULL, false) < 0) {
                cf_log_perr(cp, "Invalid value \"%s\" for config item %s",
                            cp->value, cp->attr);
 
                return -1;
        }
 
        /*
         *      Strings can be file paths...
         */
        if (fr_type_is_string(rule->type)) {
                /*
                 *      If there's out AND it's an input file, check
                 *      that we can read it.  This check allows errors
                 *      to be caught as early as possible, during
                 *      server startup.
                 */
                if (fr_rule_file_input(rule) && !cf_file_check(cp, true)) {
                error:
                        fr_value_box_clear(out);
                        return -1;
                }
                if (fr_rule_file_exists(rule) && !cf_file_check(cp, false)) goto error;
        }
 
        return 0;
}
 
/** Parses a #CONF_PAIR into a C data type
 *
 * @copybrief cf_pair_value
 * @see cf_pair_value
 *
 * @param[in] ctx       to allocate any dynamic buffers in.
 * @param[out] out      Where to write the parsed value.
 * @param[in] base      address of the structure out points into.
 *                      May be NULL in the case of manual parsing.
 * @param[in] ci        to parse.
 * @param[in] rule      to parse to.  May contain flags.
 * @return
 *      - 0 on success.
 *      - -1 on failure.
 */
int cf_pair_parse_value(TALLOC_CTX *ctx, void *out, UNUSED void *base, CONF_ITEM *ci, conf_parser_t const *rule)
{
        int             ret = 0;
        bool            cant_be_empty, tmpl;
 
        ssize_t         slen;
 
        CONF_PAIR       *cp = cf_item_to_pair(ci);
 
        cant_be_empty = fr_rule_not_empty(rule);
        tmpl = fr_rule_is_tmpl(rule);
 
        fr_assert(cp);
        fr_assert(!fr_rule_is_attribute(rule) || tmpl);         /* Attribute flag only valid for templates */
 
        if (fr_rule_required(rule)) cant_be_empty = true;       /* May want to review this in the future... */
 
        /*
         *      Everything except templates must have a base type.
         */
        if (!rule->type && !tmpl) {
                cf_log_err(cp, "Configuration pair \"%s\" must have a data type", cp->attr);
                return -1;
        }
 
        /*
         *      Catch crazy errors.
         */
        if (!cp->value) {
                cf_log_err(cp, "Configuration pair \"%s\" must have a value", cp->attr);
                return -1;
        }
 
        /*
         *      Check for zero length strings
         */
        if ((cp->value[0] == '\0') && cant_be_empty) {
                cf_log_err(cp, "Configuration pair \"%s\" must not be empty (zero length)", cp->attr);
                if (!fr_rule_required(rule)) cf_log_err(cp, "Comment item to silence this message");
        error:
                ret = -1;
                return ret;
        }
 
        if (tmpl) {
                tmpl_t                  *vpt;
                static tmpl_rules_t     rules = {
                                                .attr = {
                                                        .allow_unknown = true,
                                                        .allow_unresolved = true,
                                                        .allow_foreign = true,
                                                }
                                        };
                fr_sbuff_t              sbuff = FR_SBUFF_IN(cp->value, strlen(cp->value));
 
                rules.attr.list_def = request_attr_request;
 
                /*
                 *      Bare words are magical sometimes.
                 */
                if (cp->rhs_quote == T_BARE_WORD) {
                        /*
                         *      Attributes are parsed as attributes.
                         */
                        if (fr_rule_is_attribute(rule)) {
                                slen = tmpl_afrom_attr_substr(cp, NULL, &vpt, &sbuff, NULL, &rules);
                                if (slen < 0) goto tmpl_error;
 
                                fr_assert(vpt);
 
                                *(tmpl_t **)out = vpt;
                                goto finish;
                        }
 
                        /*
                         *      @todo - otherwise bare words are NOT parsed as attributes, they're parsed as
                         *      bare words, ala v3.
                         */
 
                } else if (fr_rule_is_attribute(rule)) {
                        cf_log_err(cp, "Unexpected quoted string.  An attribute name is required here.");
                        goto error;
                }
 
                slen = tmpl_afrom_substr(cp, &vpt, &sbuff, cp->rhs_quote,
                                         value_parse_rules_unquoted[cp->rhs_quote],
                                         &rules);
                if (slen < 0) {
                tmpl_error:
                        cf_canonicalize_error(cp, slen, fr_strerror(), cp->value);
                        goto error;
                }
                fr_assert(vpt);
 
                /*
                 *      The caller told us what data type was expected.  If we do have data, then try to cast
                 *      it to the requested type.
                 */
                if ((rule->type != FR_TYPE_VOID) && tmpl_contains_data(vpt)) {
                        slen = 0;                                       // for errors
 
                        if (tmpl_is_data_unresolved(vpt)) {
                                tmpl_cast_set(vpt, rule->type);
 
                                if (tmpl_resolve(vpt, NULL) < 0) goto tmpl_error;
 
                        } else if (rule->type != tmpl_value_type(vpt)) {
                                fr_assert(tmpl_is_data(vpt));
 
                                if (tmpl_cast_in_place(vpt, rule->type, NULL) < 0) goto tmpl_error;
                        }
                }
 
                *(tmpl_t **)out = vpt;
                goto finish;
        }
 
        /*
         *      Parse as a boxed value out of sheer laziness...
         *
         *      Then we get all the internal types for free, and only need to add
         *      one set of printing and parsing functions for new types...
         */
        {
                fr_value_box_t  vb;
 
                if (cf_pair_to_value_box(ctx, &vb, cf_item_to_pair(ci), rule) < 0) goto error;
 
                if (fr_value_box_memcpy_out(out, &vb) < 0) {
                        cf_log_perr(cp, "Failed unboxing parsed configuration item value");
                        fr_value_box_clear_value(&vb);
                        goto error;
                }
        }
 
finish:
 
        return ret;
}
 
/** Allocate a pair using the dflt value and quotation
 *
 * The pair created by this function should fed to #cf_pair_parse for parsing.
 *
 * @param[out] out      Where to write the CONF_PAIR we created with the default value.
 * @param[in] parent    being populated.
 * @param[in] cs        to parent the CONF_PAIR from.
 * @param[in] rule      to use to create the default.
 * @return
 *      - 0 on success.
 *      - -1 on failure.
 */
static int cf_pair_default(CONF_PAIR **out, void *parent, CONF_SECTION *cs, conf_parser_t const *rule)
 
{
        int             lineno = 0;
        char const      *expanded;
        CONF_PAIR       *cp;
        char            buffer[8192];
        fr_token_t      dflt_quote = rule->quote;
 
        fr_assert(rule->dflt || rule->dflt_func);
 
        if (fr_rule_required(rule)) {
                cf_log_err(cs, "Configuration pair \"%s\" must have a value", rule->name1);
                return -1;
        }
 
        /*
         *      If no default quote was set, determine it from the type
         */
        if (dflt_quote == T_INVALID) {
                if (fr_type_is_quoted(rule->type)) {
                        dflt_quote = T_DOUBLE_QUOTED_STRING;
                } else {
                        dflt_quote = T_BARE_WORD;
                }
        }
 
        /*
         *      Use the dynamic default function if set
         */
        if (rule->dflt_func) {
                if (rule->dflt_func(out, parent, cs, dflt_quote, rule) < 0) {
                        cf_log_perr(cs, "Failed producing default for \"%s\"", rule->name1);
                        return -1;
                }
 
                return 0;
        }
 
        expanded = cf_expand_variables("<internal>", lineno, cs, buffer, sizeof(buffer), rule->dflt, -1, NULL);
        if (!expanded) {
                cf_log_err(cs, "Failed expanding variable %s", rule->name1);
                return -1;
        }
 
        cp = cf_pair_alloc(cs, rule->name1, expanded, T_OP_EQ, T_BARE_WORD, dflt_quote);
        if (!cp) return -1;
 
        /*
         *      Set the ret to indicate we used a default value
         */
        *out = cp;
 
        return 1;
}
 
static int cf_pair_unescape(CONF_PAIR *cp, conf_parser_t const *rule)
{
        char const *p;
        char *str, *unescaped, *q;
 
        if (!cp->value) return 0;
 
        if (cp->rhs_quote != T_DOUBLE_QUOTED_STRING) return 0;
 
        if (!(rule->flags & CONF_FLAG_TMPL)) {
                if (rule->type != FR_TYPE_STRING) return 0;
        }
 
        if (strchr(cp->value, '\\') == NULL) return 0;
 
        str = talloc_strdup(cp, cp->value);
        if (!str) return -1;
 
        p = cp->value;
        q = str;
        while (*p) {
                unsigned int x;
 
                if (*p != '\\') {
                        *(q++) = *(p++);
                        continue;
                }
 
                p++;
                switch (*p) {
                case 'r':
                        *q++ = '\r';
                        break;
                case 'n':
                        *q++ = '\n';
                        break;
                case 't':
                        *q++ = '\t';
                        break;
 
                default:
                        if (*p >= '0' && *p <= '9' &&
                            sscanf(p, "%3o", &x) == 1) {
                                if (!x) {
                                        cf_log_err(cp, "Cannot have embedded zeros in value for %s", cp->attr);
                                        return -1;
                                }
 
                                *q++ = x;
                                p += 2;
                        } else {
                                *q++ = *p;
                        }
                        break;
                }
                p++;
        }
        *q = '\0';
 
        unescaped = talloc_typed_strdup(cp, str); /* no embedded NUL */
        if (!unescaped) return -1;
 
        talloc_free(str);
 
        /*
         *      Replace the old value with the new one.
         */
        talloc_const_free(cp->value);
        cp->value = unescaped;
 
        return 0;
}
 
/** Parses a #CONF_PAIR into a C data type, with a default value.
 *
 * @param[in] ctx       To allocate arrays and values in.
 * @param[out] out      Where to write the result.
 *                      Must not be NULL unless rule->runc is provided.
 * @param[in] base      address of the structure out points into.
 *                      May be NULL in the case of manual parsing.
 * @param[in] cs        to search for matching #CONF_PAIR in.
 * @param[in] rule      to parse #CONF_PAIR with.
 * @return
 *      - 1 if default value was used, or if there was no CONF_PAIR or dflt.
 *      - 0 on success.
 *      - -1 on error.
 *      - -2 if deprecated.
 */
static int CC_HINT(nonnull(4,5)) cf_pair_parse_internal(TALLOC_CTX *ctx, void *out, void *base,
                                                        CONF_SECTION *cs, conf_parser_t const *rule)
{
        bool            required, deprecated;
        size_t          count = 0;
        CONF_PAIR       *cp = NULL, *dflt_cp = NULL;
 
#ifndef NDEBUG
        char const      *dflt = rule->dflt;
        fr_token_t      dflt_quote = rule->quote;
#endif
        cf_parse_t      func = rule->func ? rule->func : cf_pair_parse_value;
 
        fr_assert(!fr_rule_is_tmpl(rule) || !dflt || (dflt_quote != T_INVALID)); /* We ALWAYS need a quoting type for templates */
 
        /*
         *      Functions don't necessarily *need* to write
         *      anywhere, so their data pointer can be NULL.
         */
        if (!out) {
                if (!rule->func) {
                        cf_log_err(cs, "Rule doesn't specify output destination");
                        return -1;
                }
        }
 
        required = fr_rule_required(rule);
        deprecated = fr_rule_deprecated(rule);
 
        /*
         *      If the item is multi-valued we allocate an array
         *      to hold the multiple values.
         */
        if (fr_rule_multi(rule)) {
                void            **array;
                size_t          i = 0;
 
                /*
                 *      Easier than re-allocing
                 */
                count = cf_pair_count(cs, rule->name1);
 
                /*
                 *      Multivalued, but there's no value, create a
                 *      default pair.
                 */
                if (!count) {
                        if (deprecated) return 0;
 
                        if (!fr_rule_dflt(rule)) {
                                if (required) {
                        need_value:
                                        cf_log_err(cs, "Configuration item \"%s\" must have a value", rule->name1);
                                        return -1;
                                }
                                return 1;
                        }
 
                        if (cf_pair_default(&dflt_cp, base, cs, rule) < 0) return -1;
                        count = cf_pair_count(cs, rule->name1); /* Dynamic functions can add multiple defaults */
                        if (!count) {
                                if (fr_rule_not_empty(rule)) {
                                        cf_log_err(cs, "Configuration item \"%s\" cannot be empty", rule->name1);
                                        return -1;
                                }
                                return 0;
                        }
                }
 
                if (deprecated) {
                        /*
                         *      Emit the deprecated warning in the
                         *      context of the first pair.
                         */
                        cp = cf_pair_find(cs, rule->name1);
                        fr_assert(cp);
 
                deprecated:
                        cf_log_err(cp, "Configuration pair \"%s\" is deprecated", cp->attr);
                        return -2;
                }
 
                /*
                 *      No output, so don't bother allocing the array
                 */
                if (!out) {
                        array = NULL;
 
                /*
                 *      Tmpl is outside normal range
                 */
                } else if (fr_rule_is_tmpl(rule)) {
                        MEM(array = (void **)talloc_zero_array(ctx, tmpl_t *, count));
 
                /*
                 *      Allocate an array of values.
                 *
                 *      We don't NULL terminate.  Consumer must use
                 *      talloc_array_length().
                 */
                } else {
                        array = fr_type_array_alloc(ctx, rule->type, count);
                        if (unlikely(array == NULL)) {
                                cf_log_perr(cp, "Failed allocating value array");
                                return -1;
                        }
                }
 
                while ((cp = cf_pair_find_next(cs, cp, rule->name1))) {
                        int             ret;
                        void            *entry;
                        TALLOC_CTX      *value_ctx = array;
 
                        /*
                         *      Figure out where to write the output
                         */
                        if (!array) {
                                entry = NULL;
                        } else if ((rule->type == FR_TYPE_VOID) || (rule->flags & CONF_FLAG_TMPL)) {
                                entry = &array[i++];
                        } else {
                                entry = ((uint8_t *) array) + (i++ * fr_value_box_field_sizes[rule->type]);
                        }
 
                        if (cf_pair_unescape(cp, rule) < 0) return -1;
 
                        /*
                         *      Switch between custom parsing function
                         *      and the standard value parsing function.
                         */
                        cf_pair_debug_log(cs, cp, rule);
 
                        if (cf_pair_is_parsed(cp)) continue;
                        ret = func(value_ctx, entry, base, cf_pair_to_item(cp), rule);
                        if (ret < 0) {
                                talloc_free(array);
                                return -1;
                        }
                        cf_pair_mark_parsed(cp);
                }
                if (array) *(void **)out = array;
        /*
         *      Single valued config item gets written to
         *      the data pointer directly.
         */
        } else {
                CONF_PAIR       *next;
                int             ret;
 
                cp = cf_pair_find(cs, rule->name1);
                if (!cp) {
                        if (deprecated) return 0;
 
                        if (!fr_rule_dflt(rule)) {
                                if (required) goto need_value;
                                return 1;
                        }
 
                        if (cf_pair_default(&dflt_cp, base, cs, rule) < 0) return -1;
                        cp = dflt_cp;
                        if (!cp) {
                                if (fr_rule_not_empty(rule)) {
                                        cf_log_err(cs, "Configuration item \"%s\" cannot be empty", rule->name1);
                                        return -1;
                                }
 
                                return 0;
                        }
                } else {
                        if (cf_pair_unescape(cp, rule) < 0) return -1;
                }
 
                next = cf_pair_find_next(cs, cp, rule->name1);
                if (next) {
                        cf_log_err(cf_pair_to_item(next), "Invalid duplicate configuration item '%s'", rule->name1);
                        return -1;
                }
                if (deprecated) goto deprecated;
 
                cf_pair_debug_log(cs, cp, rule);
 
                if (cf_pair_is_parsed(cp)) return 0;
                ret = func(ctx, out, base, cf_pair_to_item(cp), rule);
                if (ret < 0) return -1;
                cf_pair_mark_parsed(cp);
        }
 
        return 0;
}
 
/** Parses a #CONF_PAIR into a C data type, with a default value.
 *
 * Takes fields from a #conf_parser_t struct and uses them to parse the string value
 * of a #CONF_PAIR into a C data type matching the type argument.
 *
 * The format of the types are the same as #fr_value_box_t types.
 *
 * @note The dflt value will only be used if no matching #CONF_PAIR is found. Empty strings will not
 *       result in the dflt value being used.
 *
 * **fr_type_t to data type mappings**
 * | fr_type_t               | Data type          | Dynamically allocated  |
 * | ----------------------- | ------------------ | ---------------------- |
 * | FR_TYPE_BOOL            | ``bool``           | No                     |
 * | FR_TYPE_UINT32          | ``uint32_t``       | No                     |
 * | FR_TYPE_UINT16          | ``uint16_t``       | No                     |
 * | FR_TYPE_UINT64          | ``uint64_t``       | No                     |
 * | FR_TYPE_INT32           | ``int32_t``        | No                     |
 * | FR_TYPE_STRING          | ``char const *``   | Yes                    |
 * | FR_TYPE_IPV4_ADDR       | ``fr_ipaddr_t``    | No                     |
 * | FR_TYPE_IPV4_PREFIX     | ``fr_ipaddr_t``    | No                     |
 * | FR_TYPE_IPV6_ADDR       | ``fr_ipaddr_t``    | No                     |
 * | FR_TYPE_IPV6_PREFIX     | ``fr_ipaddr_t``    | No                     |
 * | FR_TYPE_COMBO_IP_ADDR   | ``fr_ipaddr_t``    | No                     |
 * | FR_TYPE_COMBO_IP_PREFIX | ``fr_ipaddr_t``    | No                     |
 * | FR_TYPE_TIME_DELTA      | ``fr_time_delta_t``| No                     |
 *
 * @param[in] ctx       To allocate arrays and values in.
 * @param[in] cs        to search for matching #CONF_PAIR in.
 * @param[in] name      of #CONF_PAIR to search for.
 * @param[in] type      Data type to parse #CONF_PAIR value as.
 *                      Should be one of the following ``data`` types,
 *                      and one or more of the following ``flag`` types or'd together:
 
 *      - ``data`` #FR_TYPE_BOOL                - @copybrief FR_TYPE_BOOL
 *      - ``data`` #FR_TYPE_UINT32              - @copybrief FR_TYPE_UINT32
 *      - ``data`` #FR_TYPE_UINT16              - @copybrief FR_TYPE_UINT16
 *      - ``data`` #FR_TYPE_UINT64              - @copybrief FR_TYPE_UINT64
 *      - ``data`` #FR_TYPE_INT32               - @copybrief FR_TYPE_INT32
 *      - ``data`` #FR_TYPE_STRING              - @copybrief FR_TYPE_STRING
 *      - ``data`` #FR_TYPE_IPV4_ADDR           - @copybrief FR_TYPE_IPV4_ADDR (IPv4 address with prefix 32).
 *      - ``data`` #FR_TYPE_IPV4_PREFIX         - @copybrief FR_TYPE_IPV4_PREFIX (IPv4 address with variable prefix).
 *      - ``data`` #FR_TYPE_IPV6_ADDR           - @copybrief FR_TYPE_IPV6_ADDR (IPv6 address with prefix 128).
 *      - ``data`` #FR_TYPE_IPV6_PREFIX         - @copybrief FR_TYPE_IPV6_PREFIX (IPv6 address with variable prefix).
 *      - ``data`` #FR_TYPE_COMBO_IP_ADDR       - @copybrief FR_TYPE_COMBO_IP_ADDR (IPv4/IPv6 address with
 *                                                prefix 32/128).
 *      - ``data`` #FR_TYPE_COMBO_IP_PREFIX     - @copybrief FR_TYPE_COMBO_IP_PREFIX (IPv4/IPv6 address with
 *                                                variable prefix).
 *      - ``data`` #FR_TYPE_TIME_DELTA          - @copybrief FR_TYPE_TIME_DELTA
 *      - ``flag`` #CONF_FLAG_TMPL              - @copybrief CONF_FLAG_TMPL
 *                                                Feeds the value into #tmpl_afrom_substr. Value can be
 *                                                obtained when processing requests, with #tmpl_expand or #tmpl_aexpand.
 *      - ``flag`` #FR_TYPE_DEPRECATED          - @copybrief FR_TYPE_DEPRECATED
 *      - ``flag`` #CONF_FLAG_REQUIRED          - @copybrief CONF_FLAG_REQUIRED
 *      - ``flag`` #CONF_FLAG_ATTRIBUTE         - @copybrief CONF_FLAG_ATTRIBUTE
 *      - ``flag`` #CONF_FLAG_SECRET            - @copybrief CONF_FLAG_SECRET
 *      - ``flag`` #CONF_FLAG_FILE_INPUT        - @copybrief CONF_FLAG_FILE_INPUT
 *      - ``flag`` #CONF_FLAG_FILE_OUTPUT       - @copybrief CONF_FLAG_FILE_OUTPUT
 *      - ``flag`` #CONF_FLAG_NOT_EMPTY         - @copybrief CONF_FLAG_NOT_EMPTY
 *      - ``flag`` #CONF_FLAG_MULTI             - @copybrief CONF_FLAG_MULTI
 *      - ``flag`` #CONF_FLAG_IS_SET            - @copybrief CONF_FLAG_IS_SET
 * @param[out] data             Pointer to a global variable, or pointer to a field in the struct being populated with values.
 * @param[in] dflt              value to use, if no #CONF_PAIR is found.
 * @param[in] dflt_quote        around the dflt value.
 * @return
 *      - 1 if default value was used, or if there was no CONF_PAIR or dflt.
 *      - 0 on success.
 *      - -1 on error.
 *      - -2 if deprecated.
 */
int cf_pair_parse(TALLOC_CTX *ctx, CONF_SECTION *cs, char const *name,
                  unsigned int type, void *data, char const *dflt, fr_token_t dflt_quote)
{
        conf_parser_t rule = {
                .name1 = name,
                .type = type,
                .dflt = dflt,
                .quote = dflt_quote
        };
 
        return cf_pair_parse_internal(ctx, data, NULL, cs, &rule);
}
 
/** Pre-allocate a config section structure to allow defaults to be set
 *
 * @param cs            The parent subsection.
 * @param base          pointer or variable.
 * @param rule          that may have defaults in this config section.
 * @return
 *      - 0 on success.
 *      - -1 on failure.
 */
static int cf_section_parse_init(CONF_SECTION *cs, void *base, conf_parser_t const *rule)
{
        CONF_PAIR *cp;
 
        /*
         *      This rule refers to a named subsection
         */
        if ((rule->flags & CONF_FLAG_SUBSECTION)) {
                char const      *name2 = NULL;
                CONF_SECTION    *subcs;
 
                /*
                 *      Optional MUST be listed before required ones
                 */
                if ((rule->flags & CONF_FLAG_OPTIONAL) != 0) {
                        return 0;
                }
 
                subcs = cf_section_find(cs, rule->name1, rule->name2);
 
                /*
                 *      Set the is_set field for the subsection.
                 */
                if (rule->flags & CONF_FLAG_IS_SET) {
                        bool *is_set;
 
                        is_set = rule->data ? rule->is_set_ptr : ((uint8_t *)base) + rule->is_set_offset;
                        if (is_set) *is_set = (subcs != NULL);
                }
 
                /*
                 *      It exists, we don't have to do anything else.
                 */
                if (subcs) return 0;
 
                /*
                 *      If there is no subsection, either complain,
                 *      allow it, or create it with default values.
                 */
                if (rule->flags & CONF_FLAG_REQUIRED) {
                        cf_log_err(cs, "Missing %s {} subsection", rule->name1);
                        return -1;
                }
 
                /*
                 *      It's OK for this to be missing.  Don't
                 *      initialize it.
                 */
                if ((rule->flags & CONF_FLAG_OK_MISSING) != 0) return 0;
 
                /*
                 *      If there's no subsection in the
                 *      config, BUT the conf_parser_t wants one,
                 *      then create an empty one.  This is so
                 *      that we can track the strings,
                 *      etc. allocated in the subsection.
                 */
                if (DEBUG_ENABLED4) cf_log_debug(cs, "Allocating fake section \"%s\"", rule->name1);
 
                /*
                 *      If name1 is CF_IDENT_ANY, then don't
                 *      alloc the section as we have no idea
                 *      what it should be called.
                 */
                if (rule->name1 == CF_IDENT_ANY) return 0;
 
                /*
                 *      Don't specify name2 if it's CF_IDENT_ANY
                 */
                if (rule->name2 != CF_IDENT_ANY) name2 = rule->name2;
                subcs = cf_section_alloc(cs, cs, rule->name1, name2);
                if (!subcs) return -1;
 
                return 0;
        }
 
        /*
         *      This rule refers to another conf_parse_t which is included in-line in
         *      this section.
         */
        if ((rule->flags & CONF_FLAG_REF) != 0) {
                conf_parser_t const *rule_p;
                uint8_t *sub_base = base;
 
                fr_assert(rule->subcs != NULL);
 
                sub_base += rule->offset;
 
                for (rule_p = rule->subcs; rule_p->name1; rule_p++) {
                        int ret = cf_section_parse_init(cs, sub_base, rule_p);
                        if (ret < 0) return ret;
                }
                return 0;
        }
 
        /*
         *      Don't re-initialize data which was already parsed.
         */
        cp = cf_pair_find(cs, rule->name1);
        if (cp && cp->parsed) return 0;
 
        if ((rule->type != FR_TYPE_STRING) &&
            (!(rule->flags & CONF_FLAG_FILE_INPUT)) &&
            (!(rule->flags & CONF_FLAG_FILE_OUTPUT))) {
                return 0;
        }
 
        if (rule->data) {
                *(char **) rule->data = NULL;
        } else if (base) {
                *(char **) (((char *)base) + rule->offset) = NULL;
        } else {
                return 0;
        }
 
        return 0;
}
 
static void cf_section_parse_warn(CONF_SECTION *cs)
{
        cf_item_foreach(&cs->item, ci) {
                /*
                 *      Don't recurse on sections. We can only safely
                 *      check conf pairs at the same level as the
                 *      section that was just parsed.
                 */
                if (ci->type == CONF_ITEM_SECTION) continue;
                if (ci->type == CONF_ITEM_PAIR) {
                        CONF_PAIR *cp;
 
                        cp = cf_item_to_pair(ci);
                        if (cp->parsed || cp->referenced || (ci->lineno < 0)) continue;
 
                        WARN("%s[%d]: The item '%s' is defined, but is unused by the configuration",
                             ci->filename, ci->lineno,
                             cp->attr);
                }
 
                /*
                 *      Skip everything else.
                 */
        }
}
 
/** Parse a subsection
 *
 * @note Turns out using nested structures (instead of pointers) for subsections, was actually
 *      a pretty bad design decision, and will need to be fixed at some future point.
 *      For now we have a horrible hack where only multi-subsections get an array of structures
 *      of the appropriate size.
 *
 * @param[in] ctx       to allocate any additional structures under.
 * @param[out] out      pointer to a struct/pointer to fill with data.
 * @param[in] base      address of the structure out points into.
 *                      May be NULL in the case of manual parsing.
 * @param[in] cs        to parse.
 * @param[in] rule      to parse the subcs with.
 * @return
 *      - 0 on success.
 *      - -1 on general error.
 *      - -2 if a deprecated #CONF_ITEM was found.
 */
static int cf_subsection_parse(TALLOC_CTX *ctx, void *out, void *base, CONF_SECTION *cs, conf_parser_t const *rule)
{
        CONF_SECTION            *subcs = NULL;
        int                     count = 0, i = 0, ret;
 
        size_t                  subcs_size = rule->subcs_size;
        conf_parser_t const     *rules = rule->subcs;
 
        uint8_t                 **array = NULL;
 
        fr_assert(rule->flags & CONF_FLAG_SUBSECTION);
 
        subcs = cf_section_find(cs, rule->name1, rule->name2);
        if (!subcs) return 0;
 
        /*
         *      Handle the single subsection case (which is simple)
         */
        if (!(rule->flags & CONF_FLAG_MULTI)) {
                uint8_t *buff = NULL;
 
                if (DEBUG_ENABLED4) cf_log_debug(cs, "Evaluating rules for %s section.  Output %p",
                                                 cf_section_name1(subcs), out);
 
                /*
                 *      Add any rules, so the func can just call cf_section_parse
                 *      if it wants to continue after doing its stuff.
                 */
                if (cf_section_rules_push(subcs, rules) < 0) return -1;
                if (rule->func) return rule->func(ctx, out, base, cf_section_to_item(subcs), rule);
 
                /*
                 *      FIXME: We shouldn't allow nested structures like this.
                 *      Each subsection struct should be allocated separately so
                 *      we have a clean talloc hierarchy.
                 */
                if (!subcs_size) return cf_section_parse(ctx, out, subcs);
 
                if (out) {
                        MEM(buff = talloc_zero_array(ctx, uint8_t, subcs_size));
                        if (rule->subcs_type) talloc_set_name_const(buff, rule->subcs_type);
                }
 
                ret = cf_section_parse(buff, buff, subcs);
                if (ret < 0) {
                        talloc_free(buff);
                        return ret;
                }
 
                if (out) *((uint8_t **)out) = buff;
 
                return 0;
        }
 
        fr_assert(subcs_size);
 
        /*
         *      Handle the multi subsection case (which is harder)
         */
        subcs = NULL;
        while ((subcs = cf_section_find_next(cs, subcs, rule->name1, rule->name2))) count++;
 
        /*
         *      Allocate an array to hold the subsections
         */
        if (out) {
                MEM(array = talloc_zero_array(ctx, uint8_t *, count));
                if (rule->subcs_type) talloc_set_name(array, "%s *", rule->subcs_type);
        }
        /*
         *      Start parsing...
         *
         *      Note, we allocate each subsection structure individually
         *      so that they can be used as talloc contexts and we can
         *      keep the talloc hierarchy clean.
         */
        subcs = NULL;
        while ((subcs = cf_section_find_next(cs, subcs, rule->name1, rule->name2))) {
                uint8_t *buff = NULL;
 
                if (DEBUG_ENABLED4) cf_log_debug(cs, "Evaluating rules for %s[%i] section.  Output %p",
                                                 cf_section_name1(subcs),
                                                 i, out);
 
                if (array) {
                        MEM(buff = talloc_zero_array(array, uint8_t, subcs_size));
                        if (rule->subcs_type) talloc_set_name_const(buff, rule->subcs_type);
                        array[i++] = buff;
                }
 
                /*
                 *      Add any rules, so the func can just call cf_section_parse
                 *      if it wants to continue after doing its stuff.
                 */
                if (cf_section_rules_push(subcs, rules) < 0) {
                        talloc_free(array);
                        return -1;
                }
                if (rule->func) {
                        ret = rule->func(ctx, buff, base, cf_section_to_item(subcs), rule);
                        if (ret < 0) {
                                talloc_free(array);
                                return ret;
                        }
                        continue;
                }
 
                ret = cf_section_parse(buff, buff, subcs);
                if (ret < 0) {
                        talloc_free(array);
                        return ret;
                }
        }
 
        if (out) *((uint8_t ***)out) = array;
 
        return 0;
}
 
static int cf_section_parse_rule(TALLOC_CTX *ctx, void *base, CONF_SECTION *cs, conf_parser_t const *rule)
{
        int             ret;
        bool            *is_set = NULL;
        void            *data = NULL;
 
        /*
         *      Ignore ON_READ parse rules if there's no subsequent
         *      parse functions.
         */
        if (!rule->func && rule->on_read) return 0;
 
        /*
         *      Pre-allocate the config structure to hold default values
         */
        if (cf_section_parse_init(cs, base, rule) < 0) return -1;
 
        if (rule->data) {
                data = rule->data; /* prefer this. */
        } else if (base) {
                data = ((uint8_t *)base) + rule->offset;
        }
 
        /*
         *      Handle subsections specially
         */
        if (rule->flags & CONF_FLAG_SUBSECTION) {
                return cf_subsection_parse(ctx, data, base, cs, rule);
        }
 
        /*
         *      Ignore this rule if it's a reference, as the
         *      rules it points to have been pushed by the
         *      above function.
         */
        if ((rule->flags & CONF_FLAG_REF) != 0) {
                conf_parser_t const *rule_p;
                uint8_t *sub_base = base;
 
                fr_assert(rule->subcs != NULL);
 
                sub_base += rule->offset;
 
                for (rule_p = rule->subcs; rule_p->name1; rule_p++) {
                        if (rule_p->flags & CONF_FLAG_DEPRECATED) continue;     /* Skip deprecated */
 
                        ret = cf_section_parse_rule(ctx, sub_base, cs, rule_p);
                        if (ret < 0) return ret;
                }
 
                /*
                 *      Ensure we have a proper terminator, type so we catch
                 *      missing terminators reliably
                 */
                fr_cond_assert(rule_p->type == conf_term.type);
 
                return 0;
        }
 
        /*
         *      Else it's a CONF_PAIR
         */
 
        /*
         *      Pair either needs an output destination or
         *      there needs to be a function associated with
         *      it.
         */
        if (!data && !rule->func) {
                cf_log_err(cs, "Rule doesn't specify output destination");
                return -1;
        }
 
        /*
         *      Get pointer to where we need to write out
         *      whether the pointer was set.
         */
        if (rule->flags & CONF_FLAG_IS_SET) {
                is_set = rule->data ? rule->is_set_ptr : ((uint8_t *)base) + rule->is_set_offset;
        }
 
        /*
         *      Parse the pair we found, or a default value.
         */
        ret = cf_pair_parse_internal(ctx, data, base, cs, rule);
        switch (ret) {
        case 1:         /* Used default (or not present) */
                if (is_set) *is_set = false;
                ret = 0;
                break;
 
        case 0:         /* OK */
                if (is_set) *is_set = true;
                break;
 
        case -1:        /* Parse error */
                break;
 
        case -2:        /* Deprecated CONF ITEM */
                if (((rule + 1)->offset && ((rule + 1)->offset == rule->offset)) ||
                    ((rule + 1)->data && ((rule + 1)->data == rule->data))) {
                        cf_log_err(cs, "Replace \"%s\" with \"%s\"", rule->name1,
                                   (rule + 1)->name1);
                }
                break;
        }
 
        return ret;
}
 
/** Parse a configuration section into user-supplied variables
 *
 * @param[in] ctx               to allocate any strings, or additional structures in.
 *                              Usually the same as base, unless base is a nested struct.
 * @param[out] base             pointer to a struct to fill with data.
 * @param[in] cs                to parse.
 * @return
 *      - 0 on success.
 *      - -1 on general error.
 *      - -2 if a deprecated #CONF_ITEM was found.
 */
int cf_section_parse(TALLOC_CTX *ctx, void *base, CONF_SECTION *cs)
{
        CONF_DATA const *rule_cd = NULL;
 
        if (!cs->name2) {
                cf_log_debug(cs, "%.*s%s {", SECTION_SPACE(cs), parse_spaces, cs->name1);
        } else {
                cf_log_debug(cs, "%.*s%s %s {", SECTION_SPACE(cs), parse_spaces, cs->name1, cs->name2);
        }
 
        /*
         *      Loop over all the child rules of the section
         */
        while ((rule_cd = cf_data_find_next(cs, rule_cd, conf_parser_t, CF_IDENT_ANY))) {
                int             ret;
                conf_parser_t   *rule;
 
                rule = cf_data_value(rule_cd);
 
                ret = cf_section_parse_rule(ctx, base, cs, rule);
                if (ret < 0) return ret;
        }
 
        cs->base = base;
 
        /*
         *      Warn about items in the configuration which weren't
         *      checked during parsing.
         */
        if (DEBUG_ENABLED4) cf_section_parse_warn(cs);
 
        cf_log_debug(cs, "%.*s}", SECTION_SPACE(cs), parse_spaces);
 
        return 0;
}
 
/*
 *      Pass2 fixups on tmpl_t
 *
 *      We don't have (or need yet) cf_pair_parse_pass2(), so we just
 *      do it for tmpls.
 */
static int cf_parse_tmpl_pass2(UNUSED CONF_SECTION *cs, tmpl_t **out, CONF_PAIR *cp, fr_type_t type,
                               bool attribute, fr_dict_t const *dict_def)
{
        tmpl_t *vpt = *out;
 
        fr_assert(vpt); /* We need something to resolve */
 
        if (tmpl_resolve(vpt, &(tmpl_res_rules_t){ .dict_def = dict_def, .force_dict_def = (dict_def != NULL)}) < 0) {
                cf_log_perr(cp, "Failed processing configuration item '%s'", cp->attr);
                return -1;
        }
 
        if (attribute && !tmpl_is_attr(vpt)) {
                cf_log_err(cp, "Expected attr got %s",
                           tmpl_type_to_str(vpt->type));
                return -1;
        }
 
        switch (vpt->type) {
        /*
         *      All attributes should have been defined by this point.
         */
        case TMPL_TYPE_ATTR_UNRESOLVED:
                cf_log_err(cp, "Unknown attribute '%s'", tmpl_attr_tail_unresolved(vpt));
                return -1;
 
        case TMPL_TYPE_DATA_UNRESOLVED:
                /*
                 *      Try to realize the underlying type, if at all possible.
                 */
                if (!attribute && type && (tmpl_cast_in_place(vpt, type, NULL) < 0)) {
                        cf_log_perr(cp, "Failed processing configuration item '%s'", cp->attr);
                        return -1;
                }
                break;
 
        case TMPL_TYPE_ATTR:
        case TMPL_TYPE_DATA:
        case TMPL_TYPE_EXEC:
        case TMPL_TYPE_EXEC_UNRESOLVED:
        case TMPL_TYPE_XLAT:
        case TMPL_TYPE_XLAT_UNRESOLVED:
                break;
 
        case TMPL_TYPE_UNINITIALISED:
        case TMPL_TYPE_REGEX:
        case TMPL_TYPE_REGEX_UNCOMPILED:
        case TMPL_TYPE_REGEX_XLAT:
        case TMPL_TYPE_REGEX_XLAT_UNRESOLVED:
        case TMPL_TYPE_NULL:
        case TMPL_TYPE_MAX:
                fr_assert(0);
                /* Don't add default */
        }
 
        return 0;
}
 
/** Fixup xlat expansions and attributes
 *
 * @param[out] base start of structure to write #tmpl_t s to.
 * @param[in] cs CONF_SECTION to fixup.
 * @return
 *      - 0 on success.
 *      - -1 on failure (parse errors etc...).
 */
int cf_section_parse_pass2(void *base, CONF_SECTION *cs)
{
        CONF_DATA const *rule_cd = NULL;
 
        while ((rule_cd = cf_data_find_next(cs, rule_cd, conf_parser_t, CF_IDENT_ANY))) {
                bool                    attribute, multi, is_tmpl, is_xlat;
                CONF_PAIR               *cp;
                conf_parser_t           *rule = cf_data_value(rule_cd);
                void                    *data;
                fr_type_t               type = rule->type;
                conf_parser_flags_t     flags = rule->flags;
                fr_dict_t const         *dict = NULL;
 
                is_tmpl = (flags & CONF_FLAG_TMPL);
                is_xlat = (flags & CONF_FLAG_XLAT);
                attribute = (flags & CONF_FLAG_ATTRIBUTE);
                multi = (flags & CONF_FLAG_MULTI);
 
                /*
                 *      It's a section, recurse!
                 */
                if (flags & CONF_FLAG_SUBSECTION) {
                        uint8_t         *subcs_base;
                        CONF_SECTION    *subcs = cf_section_find(cs, rule->name1, rule->name2);
 
                        /*
                         *      Select base by whether this is a nested struct,
                         *      or a pointer to another struct.
                         */
                        if (!base) {
                                subcs_base = NULL;
                        } else if (multi) {
                                size_t          j, len;
                                uint8_t         **array;
 
                                array = *(uint8_t ***)(((uint8_t *)base) + rule->offset);
                                len = talloc_array_length(array);
 
                                for (j = 0; j < len; j++) if (cf_section_parse_pass2(array[j], subcs) < 0) return -1;
                                continue;
                        } else {
                                subcs_base = (uint8_t *)base + rule->offset;
                        }
 
                        if (cf_section_parse_pass2(subcs_base, subcs) < 0) return -1;
 
                        continue;
                }
 
                /*
                 *      Find the CONF_PAIR, may still not exist if there was
                 *      no default set for the conf_parser_t.
                 */
                cp = cf_pair_find(cs, rule->name1);
                if (!cp) continue;
 
                /*
                 *      Figure out which data we need to fix.
                 */
                data = rule->data; /* prefer this. */
                if (!data && base) data = ((char *)base) + rule->offset;
                if (!data) continue;
 
                /*
                 *      Non-xlat expansions shouldn't have xlat!
                 *
                 *      Except other libraries like libkafka may be the ones
                 *      doing the actual expansion, so we don't _know_
                 *      if the xlatlike value is destined for use in FreeRADIUS
                 *      or not, so we can't definitely determine if this is an
                 *      error.
                 *
                 *      Code left in place to warn other people off re-adding
                 *      this check in future.
                 */
#if 0
                if (!is_xlat && !is_tmpl) {
                        /*
                         *      Ignore %{... in shared secrets.
                         *      They're never dynamically expanded.
                         */
                        if ((rule->flags & CONF_FLAG_SECRET) != 0) continue;
 
                        if (strstr(cp->value, "%{") != NULL) {
                                cf_log_err(cp, "Found dynamic expansion in string which "
                                           "will not be dynamically expanded");
                                return -1;
                        }
                        continue;
                }
#endif
 
                /*
                 *      Search for dictionary data somewhere in the virtual
                 *      server.
                 */
                dict = virtual_server_dict_by_child_ci(cf_section_to_item(cs));
 
                /*
                 *      Parse (and throw away) the xlat string (for validation).
                 *
                 *      FIXME: All of these should be converted from CONF_FLAG_XLAT
                 *      to CONF_FLAG_TMPL.
                 */
                if (is_xlat) {
                        ssize_t         slen;
                        xlat_exp_head_t *xlat;
 
                redo:
                        xlat = NULL;
 
                        /*
                         *      xlat expansions should be parseable.
                         */
                        slen = xlat_tokenize(cs, &xlat,
                                             &FR_SBUFF_IN(cp->value, talloc_array_length(cp->value) - 1), NULL,
                                             &(tmpl_rules_t) {
                                                     .attr = {
                                                             .dict_def = dict,
                                                             .list_def = request_attr_request,
                                                             .allow_unknown = false,
                                                             .allow_unresolved = false,
                                                             .allow_foreign = (dict == NULL)
                                                     },
                                             }, 0);
                        if (slen < 0) {
                                char *spaces, *text;
 
                                fr_canonicalize_error(cs, &spaces, &text, slen, cp->value);
 
                                cf_log_err(cp, "Failed parsing expansion string:");
                                cf_log_err(cp, "%s", text);
                                cf_log_perr(cp, "%s^", spaces);
 
                                talloc_free(spaces);
                                talloc_free(text);
                                talloc_free(xlat);
                                return -1;
                        }
 
                        talloc_free(xlat);
 
                        /*
                         *      If the "multi" flag is set, check all of them.
                         */
                        if (multi) {
                                cp = cf_pair_find_next(cs, cp, cp->attr);
                                if (cp) goto redo;
                        }
                        continue;
 
                /*
                 *      Parse the pair into a template
                 */
                } else if (is_tmpl && !multi) {
                        if (cf_parse_tmpl_pass2(cs, (tmpl_t **)data, cp, type, attribute, dict) < 0) {
                                return -1;
                        }
 
                } else if (is_tmpl) {
                        size_t i;
                        char const *name = cp->attr;
                        tmpl_t **array = *(tmpl_t ***) data;
 
                        for (i = 0; i < talloc_array_length(array); i++, cp = cf_pair_find_next(cs, cp, name)) {
                                if (!cp) break;
 
                                if (cf_parse_tmpl_pass2(cs, &array[i], cp, type, attribute, dict) < 0) {
                                        return -1;
                                }
                        }
                }
        }
 
        return 0;
}
 
 
/** Add a single rule to a #CONF_SECTION
 *
 * @param[in] cs        to add rules to.
 * @param[in] rule      to add.
 * @param[in] filename  where the rule was pushed.
 * @param[in] lineno    where the rule was pushed.
 * @return
 *      - 0 on success.
 *      - -1 if the rules added conflict.
 */
int _cf_section_rule_push(CONF_SECTION *cs, conf_parser_t const *rule, char const *filename, int lineno)
{
        char const *name1, *name2;
 
        if (!cs || !rule) return 0;
 
        name1 = rule->name1 == CF_IDENT_ANY ? "__any__" : rule->name1;
        name2 = rule->name2 == CF_IDENT_ANY ? "__any__" : rule->name2;
 
        if (DEBUG_ENABLED4) {
                cf_log_debug(cs, "Pushed parse rule to %s section: %s %s",
                             cf_section_name1(cs),
                             name1, rule->flags & CONF_FLAG_SUBSECTION ? "{}": "");
        }
 
        /*
         *      Qualifying with name prevents duplicate rules being added
         *
         *      Fixme maybe?.. Can't have a section and pair with the same name.
         */
        if (!_cf_data_add_static(CF_TO_ITEM(cs), rule, "conf_parser_t", name1, filename, lineno)) {
                CONF_DATA const *cd;
                conf_parser_t *old;
 
                cd = cf_data_find(CF_TO_ITEM(cs), conf_parser_t, name1);
                old = cf_data_value(cd);
                fr_assert(old != NULL);
 
                /*
                 *      Shut up about duplicates.
                 */
                if (memcmp(rule, old, sizeof(*rule)) == 0) {
                        return 0;
                }
 
                /*
                 *      Remove any ON_READ callbacks, and add the new
                 *      rule in its place.
                 */
                if (old->on_read) {
                        CONF_DATA *cd1;
 
                        /*
                         *      Over-write the rule in place.
                         *
                         *      We'd like to call cf_item_remove(), but
                         *      that apparently doesn't work for
                         *      CONF_DATA.  We don't need to
                         *      free/alloc one, so re-using this is
                         *      fine.
                         */
                        memcpy(&cd1, &cd, sizeof(cd1));
                        cd1->data = rule;
                        cd1->item.filename = filename;
                        cd1->item.lineno = lineno;
                        return 0;
                }
 
                /*
                 *      If we have a duplicate sub-section, just
                 *      recurse and add the new sub-rules to the
                 *      existing sub-section.
                 */
                if (rule->flags & CONF_FLAG_SUBSECTION) {
                        CONF_SECTION *subcs;
 
                        subcs = cf_section_find(cs, name1, name2);
                        if (!subcs) {
                                cf_log_err(cs, "Failed finding '%s' subsection", name1);
                                cf_item_debug(cs);
                                return -1;
                        }
 
                        /*
                         *      The old rules were delayed until we pushed a matching subsection which is actually used.
                         */
                        if ((old->flags & CONF_FLAG_OPTIONAL) != 0) {
                                if (cf_section_rules_push(subcs, old->subcs) < 0) return -1;
                        }
 
                        return cf_section_rules_push(subcs, rule->subcs);
                }
 
                cf_log_err(cs, "Data of type %s with name \"%s\" already exists. "
                           "Existing data added %s[%i]", "conf_parser_t",
                           name1, cd->item.filename, cd->item.lineno);
 
                cf_item_debug(cs);
                return -1;
        }
 
        return 0;
}
 
/** Add an array of parse rules to a #CONF_SECTION
 *
 * @param[in] cs        to add rules to.
 * @param[in] rules     to add.  Last element should have NULL name field.
 * @param[in] filename  where the rule was pushed.
 * @param[in] lineno    where the rule was pushed.
 * @return
 *      - 0 on success.
 *      - -1 on failure.
 */
int _cf_section_rules_push(CONF_SECTION *cs, conf_parser_t const *rules, char const *filename, int lineno)
{
        conf_parser_t const *rule_p;
 
        if (!cs || !rules) return 0;
 
        for (rule_p = rules; rule_p->name1; rule_p++) {
                if (rule_p->flags & CONF_FLAG_DEPRECATED) continue;     /* Skip deprecated */
                if (_cf_section_rule_push(cs, rule_p, filename, lineno) < 0) return -1;
        }
 
        /*
         *      Ensure we have a proper terminator, type so we catch
         *      missing terminators reliably
         */
        fr_cond_assert(rule_p->type == conf_term.type);
 
        return 0;
}
 
/** Generic function for parsing conf pair values as int
 *
 * @note This should be used for enum types as c99 6.4.4.3 states that the enumeration
 * constants are of type int.
 *
 */
int cf_table_parse_int(UNUSED TALLOC_CTX *ctx, void *out, UNUSED void *parent,
                       CONF_ITEM *ci, conf_parser_t const *rule)
{
        int                             num;
        cf_table_parse_ctx_t const      *parse_ctx = rule->uctx;
 
        if (cf_pair_in_table(&num, parse_ctx->table, *parse_ctx->len, cf_item_to_pair(ci)) < 0) return -1;
 
        *((int *)out) = num;
 
        return 0;
}
 
/** Generic function for parsing conf pair values as int32_t (FR_TYPE_INT32)
 *
 */
int cf_table_parse_int32(UNUSED TALLOC_CTX *ctx, void *out, UNUSED void *parent,
                         CONF_ITEM *ci, conf_parser_t const *rule)
{
        int32_t                         num;
        cf_table_parse_ctx_t const      *parse_ctx = rule->uctx;
 
        if (cf_pair_in_table(&num, parse_ctx->table, *parse_ctx->len, cf_item_to_pair(ci)) < 0) return -1;
 
        *((int32_t *)out) = num;
 
        return 0;
}
 
/** Generic function for parsing conf pair values as int32_t (FR_TYPE_UINT32)
 *
 */
int cf_table_parse_uint32(UNUSED TALLOC_CTX *ctx, void *out, UNUSED void *parent,
                          CONF_ITEM *ci, conf_parser_t const *rule)
{
        int32_t                         num;
        cf_table_parse_ctx_t const      *parse_ctx = rule->uctx;
 
        if (cf_pair_in_table(&num, parse_ctx->table, *parse_ctx->len, cf_item_to_pair(ci)) < 0) return -1;
        if (num < 0) {
                cf_log_err(ci, "Resolved value must be a positive integer, got %i", num);
                return -1;
        }
        *((uint32_t *)out) = (uint32_t)num;
 
        return 0;
}
 
/** Generic function for resolving UID strings to uid_t values
 *
 * Type should be FR_TYPE_VOID, struct field should be a uid_t.
 */
int cf_parse_uid(TALLOC_CTX *ctx, void *out, UNUSED void *parent,
                 CONF_ITEM *ci, UNUSED conf_parser_t const *rule)
{
        if (fr_perm_uid_from_str(ctx, (uid_t *)out, cf_pair_value(cf_item_to_pair(ci))) < 0) {
                cf_log_perr(ci, "Failed resolving UID");
                return -1;
        }
 
        return 0;
}
 
/** Generic function for resolving GID strings to uid_t values
 *
 * Type should be FR_TYPE_VOID, struct field should be a gid_t.
 */
int cf_parse_gid(TALLOC_CTX *ctx, void *out, UNUSED void *parent,
                 CONF_ITEM *ci, UNUSED conf_parser_t const *rule)
{
        if (fr_perm_gid_from_str(ctx, (gid_t *)out, cf_pair_value(cf_item_to_pair(ci))) < 0) {
                cf_log_perr(ci, "Failed resolving GID");
                return -1;
        }
 
        return 0;
}
 
/** Generic function for resolving permissions to a mode-t
 *
 * Type should be FR_TYPE_VOID, struct field should be a gid_t.
 */
int cf_parse_permissions(UNUSED TALLOC_CTX *ctx, void *out, UNUSED void *parent,
                         CONF_ITEM *ci, UNUSED conf_parser_t const *rule)
{
        mode_t mode;
        char const *name = cf_pair_value(cf_item_to_pair(ci));
 
        if (fr_perm_mode_from_str(&mode, name) < 0) {
                cf_log_perr(ci, "Invalid permissions string");
                return -1;
        }
 
        *(mode_t *) out = mode;
 
        return 0;
}
 
/** NULL callback for sections
 *
 *  This callback exists only as a place-holder to ensure that the
 *  nested on_read functions are called.  The conf file routines won't
 *  recurse into every conf_parser_t section to check if there's an
 *  "on_read" callback.  So this place-holder is a signal to do that.
 *
 * @param[in] ctx       to allocate data in.
 * @param[out] out      Unused
 * @param[in] parent    Base structure address.
 * @param[in] ci        #CONF_SECTION containing the current section.
 * @param[in] rule      unused.
 * @return
 *      - 0 on success.
 *      - -1 on failure.
 */
int cf_null_on_read(UNUSED TALLOC_CTX *ctx, UNUSED void *out, UNUSED void *parent,
                    UNUSED CONF_ITEM *ci, UNUSED conf_parser_t const *rule)
{
        return 0;
}