/*-------------------------------------------------------------------------

 *

 * hbafuncs.c

 *    Support functions for SQL views of authentication files.

 *

 * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group

 * Portions Copyright (c) 1994, Regents of the University of California

 *

 *

 * IDENTIFICATION

 *    src/backend/utils/adt/hbafuncs.c

 *

 *-------------------------------------------------------------------------

 */

#include "postgres.h"

#include "catalog/objectaddress.h"

#include "common/ip.h"

#include "funcapi.h"

#include "libpq/hba.h"

#include "utils/array.h"

#include "utils/builtins.h"

#include "utils/guc.h"

static ArrayType *get_hba_options(HbaLine *hba);

static void fill_hba_line(Tuplestorestate *tuple_store, TupleDesc tupdesc,

              int rule_number, char *filename, int lineno,

              HbaLine *hba, const char *err_msg);

static void fill_hba_view(Tuplestorestate *tuple_store, TupleDesc tupdesc);

static void fill_ident_line(Tuplestorestate *tuple_store, TupleDesc tupdesc,

              int map_number, char *filename, int lineno,

              IdentLine *ident, const char *err_msg);

static void fill_ident_view(Tuplestorestate *tuple_store, TupleDesc tupdesc);

/*

 * This macro specifies the maximum number of authentication options

 * that are possible with any given authentication method that is supported.

 * Currently LDAP supports 12, and there are 3 that are not dependent on

 * the auth method here.  It may not actually be possible to set all of them

 * at the same time, but we'll set the macro value high enough to be

 * conservative and avoid warnings from static analysis tools.

 */

#define MAX_HBA_OPTIONS 15

/*

 * Create a text array listing the options specified in the HBA line.

 * Return NULL if no options are specified.

 */

static ArrayType *

get_hba_options(HbaLine *hba)

{

  int     noptions;

  Datum   options[MAX_HBA_OPTIONS];

  noptions = 0;

  if (hba->auth_method == uaGSS || hba->auth_method == uaSSPI)

  {

    if (hba->include_realm)

      options[noptions++] =

        CStringGetTextDatum("include_realm=true");

    if (hba->krb_realm)

      options[noptions++] =

        CStringGetTextDatum(psprintf("krb_realm=%s", hba->krb_realm));

  }

  if (hba->usermap)

    options[noptions++] =

      CStringGetTextDatum(psprintf("map=%s", hba->usermap));

  if (hba->clientcert != clientCertOff)

    options[noptions++] =

      CStringGetTextDatum(psprintf("clientcert=%s", (hba->clientcert == clientCertCA) ? "verify-ca" : "verify-full"));

  if (hba->pamservice)

    options[noptions++] =

      CStringGetTextDatum(psprintf("pamservice=%s", hba->pamservice));

  if (hba->auth_method == uaLDAP)

  {

    if (hba->ldapserver)

      options[noptions++] =

        CStringGetTextDatum(psprintf("ldapserver=%s", hba->ldapserver));

    if (hba->ldapport)

      options[noptions++] =

        CStringGetTextDatum(psprintf("ldapport=%d", hba->ldapport));

    if (hba->ldapscheme)

      options[noptions++] =

        CStringGetTextDatum(psprintf("ldapscheme=%s", hba->ldapscheme));

    if (hba->ldaptls)

      options[noptions++] =

        CStringGetTextDatum("ldaptls=true");

    if (hba->ldapprefix)

      options[noptions++] =

        CStringGetTextDatum(psprintf("ldapprefix=%s", hba->ldapprefix));

    if (hba->ldapsuffix)

      options[noptions++] =

        CStringGetTextDatum(psprintf("ldapsuffix=%s", hba->ldapsuffix));

    if (hba->ldapbasedn)

      options[noptions++] =

        CStringGetTextDatum(psprintf("ldapbasedn=%s", hba->ldapbasedn));

    if (hba->ldapbinddn)

      options[noptions++] =

        CStringGetTextDatum(psprintf("ldapbinddn=%s", hba->ldapbinddn));

    if (hba->ldapbindpasswd)

      options[noptions++] =

        CStringGetTextDatum(psprintf("ldapbindpasswd=%s",

                       hba->ldapbindpasswd));

    if (hba->ldapsearchattribute)

      options[noptions++] =

        CStringGetTextDatum(psprintf("ldapsearchattribute=%s",

                       hba->ldapsearchattribute));

    if (hba->ldapsearchfilter)

      options[noptions++] =

        CStringGetTextDatum(psprintf("ldapsearchfilter=%s",

                       hba->ldapsearchfilter));

    if (hba->ldapscope)

      options[noptions++] =

        CStringGetTextDatum(psprintf("ldapscope=%d", hba->ldapscope));

  }

  if (hba->auth_method == uaRADIUS)

  {

    if (hba->radiusservers_s)

      options[noptions++] =

        CStringGetTextDatum(psprintf("radiusservers=%s", hba->radiusservers_s));

    if (hba->radiussecrets_s)

      options[noptions++] =

        CStringGetTextDatum(psprintf("radiussecrets=%s", hba->radiussecrets_s));

    if (hba->radiusidentifiers_s)

      options[noptions++] =

        CStringGetTextDatum(psprintf("radiusidentifiers=%s", hba->radiusidentifiers_s));

    if (hba->radiusports_s)

      options[noptions++] =

        CStringGetTextDatum(psprintf("radiusports=%s", hba->radiusports_s));

  }

  if (hba->auth_method == uaOAuth)

  {

    if (hba->oauth_issuer)

      options[noptions++] =

        CStringGetTextDatum(psprintf("issuer=%s", hba->oauth_issuer));

    if (hba->oauth_scope)

      options[noptions++] =

        CStringGetTextDatum(psprintf("scope=%s", hba->oauth_scope));

    if (hba->oauth_validator)

      options[noptions++] =

        CStringGetTextDatum(psprintf("validator=%s", hba->oauth_validator));

    if (hba->oauth_skip_usermap)

      options[noptions++] =

        CStringGetTextDatum(psprintf("delegate_ident_mapping=true"));

  }

  /* If you add more options, consider increasing MAX_HBA_OPTIONS. */

  Assert(noptions <= MAX_HBA_OPTIONS);

  if (noptions > 0)

    return construct_array_builtin(options, noptions, TEXTOID);

  else

    return NULL;

}

/* Number of columns in pg_hba_file_rules view */

#define NUM_PG_HBA_FILE_RULES_ATTS   11

/*

 * fill_hba_line

 *    Build one row of pg_hba_file_rules view, add it to tuplestore.

 *

 * tuple_store: where to store data

 * tupdesc: tuple descriptor for the view

 * rule_number: unique identifier among all valid rules

 * filename: configuration file name (must always be valid)

 * lineno: line number of configuration file (must always be valid)

 * hba: parsed line data (can be NULL, in which case err_msg should be set)

 * err_msg: error message (NULL if none)

 *

 * Note: leaks memory, but we don't care since this is run in a short-lived

 * memory context.

 */

static void

fill_hba_line(Tuplestorestate *tuple_store, TupleDesc tupdesc,

        int rule_number, char *filename, int lineno, HbaLine *hba,

        const char *err_msg)

{

  Datum   values[NUM_PG_HBA_FILE_RULES_ATTS];

  bool    nulls[NUM_PG_HBA_FILE_RULES_ATTS];

  char    buffer[NI_MAXHOST];

  HeapTuple tuple;

  int     index;

  ListCell   *lc;

  const char *typestr;

  const char *addrstr;

  const char *maskstr;

  ArrayType  *options;

  Assert(tupdesc->natts == NUM_PG_HBA_FILE_RULES_ATTS);

  memset(values, 0, sizeof(values));

  memset(nulls, 0, sizeof(nulls));

  index = 0;

  /* rule_number, nothing on error */

  if (err_msg)

    nulls[index++] = true;

  else

    values[index++] = Int32GetDatum(rule_number);

  /* file_name */

  values[index++] = CStringGetTextDatum(filename);

  /* line_number */

  values[index++] = Int32GetDatum(lineno);

  if (hba != NULL)

  {

    /* type */

    /* Avoid a default: case so compiler will warn about missing cases */

    typestr = NULL;

    switch (hba->conntype)

    {

      case ctLocal:

        typestr = "local";

        break;

      case ctHost:

        typestr = "host";

        break;

      case ctHostSSL:

        typestr = "hostssl";

        break;

      case ctHostNoSSL:

        typestr = "hostnossl";

        break;

      case ctHostGSS:

        typestr = "hostgssenc";

        break;

      case ctHostNoGSS:

        typestr = "hostnogssenc";

        break;

    }

    if (typestr)

      values[index++] = CStringGetTextDatum(typestr);

    else

      nulls[index++] = true;

    /* database */

    if (hba->databases)

    {

      /*

       * Flatten AuthToken list to string list.  It might seem that we

       * should re-quote any quoted tokens, but that has been rejected

       * on the grounds that it makes it harder to compare the array

       * elements to other system catalogs.  That makes entries like

       * "all" or "samerole" formally ambiguous ... but users who name

       * databases/roles that way are inflicting their own pain.

       */

      List     *names = NIL;

      foreach(lc, hba->databases)

      {

        AuthToken  *tok = lfirst(lc);

        names = lappend(names, tok->string);

      }

      values[index++] = PointerGetDatum(strlist_to_textarray(names));

    }

    else

      nulls[index++] = true;

    /* user */

    if (hba->roles)

    {

      /* Flatten AuthToken list to string list; see comment above */

      List     *roles = NIL;

      foreach(lc, hba->roles)

      {

        AuthToken  *tok = lfirst(lc);

        roles = lappend(roles, tok->string);

      }

      values[index++] = PointerGetDatum(strlist_to_textarray(roles));

    }

    else

      nulls[index++] = true;

    /* address and netmask */

    /* Avoid a default: case so compiler will warn about missing cases */

    addrstr = maskstr = NULL;

    switch (hba->ip_cmp_method)

    {

      case ipCmpMask:

        if (hba->hostname)

        {

          addrstr = hba->hostname;

        }

        else

        {

          /*

           * Note: if pg_getnameinfo_all fails, it'll set buffer to

           * "???", which we want to return.

           */

          if (hba->addrlen > 0)

          {

            if (pg_getnameinfo_all(&hba->addr, hba->addrlen,

                         buffer, sizeof(buffer),

                         NULL, 0,

                         NI_NUMERICHOST) == 0)

              clean_ipv6_addr(hba->addr.ss_family, buffer);

            addrstr = pstrdup(buffer);

          }

          if (hba->masklen > 0)

          {

            if (pg_getnameinfo_all(&hba->mask, hba->masklen,

                         buffer, sizeof(buffer),

                         NULL, 0,

                         NI_NUMERICHOST) == 0)

              clean_ipv6_addr(hba->mask.ss_family, buffer);

            maskstr = pstrdup(buffer);

          }

        }

        break;

      case ipCmpAll:

        addrstr = "all";

        break;

      case ipCmpSameHost:

        addrstr = "samehost";

        break;

      case ipCmpSameNet:

        addrstr = "samenet";

        break;

    }

    if (addrstr)

      values[index++] = CStringGetTextDatum(addrstr);

    else

      nulls[index++] = true;

    if (maskstr)

      values[index++] = CStringGetTextDatum(maskstr);

    else

      nulls[index++] = true;

    /* auth_method */

    values[index++] = CStringGetTextDatum(hba_authname(hba->auth_method));

    /* options */

    options = get_hba_options(hba);

    if (options)

      values[index++] = PointerGetDatum(options);

    else

      nulls[index++] = true;

  }

  else

  {

    /* no parsing result, so set relevant fields to nulls */

    memset(&nulls[3], true, (NUM_PG_HBA_FILE_RULES_ATTS - 4) * sizeof(bool));

  }

  /* error */

  if (err_msg)

    values[NUM_PG_HBA_FILE_RULES_ATTS - 1] = CStringGetTextDatum(err_msg);

  else

    nulls[NUM_PG_HBA_FILE_RULES_ATTS - 1] = true;

  tuple = heap_form_tuple(tupdesc, values, nulls);

  tuplestore_puttuple(tuple_store, tuple);

}

/*

 * fill_hba_view

 *    Read the pg_hba.conf file and fill the tuplestore with view records.

 */

static void

fill_hba_view(Tuplestorestate *tuple_store, TupleDesc tupdesc)

{

  FILE     *file;

  List     *hba_lines = NIL;

  ListCell   *line;

  int     rule_number = 0;

  MemoryContext hbacxt;

  MemoryContext oldcxt;

  /*

   * In the unlikely event that we can't open pg_hba.conf, we throw an

   * error, rather than trying to report it via some sort of view entry.

   * (Most other error conditions should result in a message in a view

   * entry.)

   */

  file = open_auth_file(HbaFileName, ERROR, 0, NULL);

  tokenize_auth_file(HbaFileName, file, &hba_lines, DEBUG3, 0);

  /* Now parse all the lines */

  hbacxt = AllocSetContextCreate(CurrentMemoryContext,

                   "hba parser context",

                   ALLOCSET_SMALL_SIZES);

  oldcxt = MemoryContextSwitchTo(hbacxt);

  foreach(line, hba_lines)

  {

    TokenizedAuthLine *tok_line = (TokenizedAuthLine *) lfirst(line);

    HbaLine    *hbaline = NULL;

    /* don't parse lines that already have errors */

    if (tok_line->err_msg == NULL)

      hbaline = parse_hba_line(tok_line, DEBUG3);

    /* No error, set a new rule number */

    if (tok_line->err_msg == NULL)

      rule_number++;

    fill_hba_line(tuple_store, tupdesc, rule_number,

            tok_line->file_name, tok_line->line_num, hbaline,

            tok_line->err_msg);

  }

  /* Free tokenizer memory */

  free_auth_file(file, 0);

  /* Free parse_hba_line memory */

  MemoryContextSwitchTo(oldcxt);

  MemoryContextDelete(hbacxt);

}

/*

 * pg_hba_file_rules

 *

 * SQL-accessible set-returning function to return all the entries in the

 * pg_hba.conf file.

 */

Datum

pg_hba_file_rules(PG_FUNCTION_ARGS)

{

  ReturnSetInfo *rsi;

  /*

   * Build tuplestore to hold the result rows.  We must use the Materialize

   * mode to be safe against HBA file changes while the cursor is open. It's

   * also more efficient than having to look up our current position in the

   * parsed list every time.

   */

  InitMaterializedSRF(fcinfo, 0);

  /* Fill the tuplestore */

  rsi = (ReturnSetInfo *) fcinfo->resultinfo;

  fill_hba_view(rsi->setResult, rsi->setDesc);

  PG_RETURN_NULL();

}

/* Number of columns in pg_ident_file_mappings view */

#define NUM_PG_IDENT_FILE_MAPPINGS_ATTS  7

/*

 * fill_ident_line: build one row of pg_ident_file_mappings view, add it to

 * tuplestore

 *

 * tuple_store: where to store data

 * tupdesc: tuple descriptor for the view

 * map_number: unique identifier among all valid maps

 * filename: configuration file name (must always be valid)

 * lineno: line number of configuration file (must always be valid)

 * ident: parsed line data (can be NULL, in which case err_msg should be set)

 * err_msg: error message (NULL if none)

 *

 * Note: leaks memory, but we don't care since this is run in a short-lived

 * memory context.

 */

static void

fill_ident_line(Tuplestorestate *tuple_store, TupleDesc tupdesc,

        int map_number, char *filename, int lineno, IdentLine *ident,

        const char *err_msg)

{

  Datum   values[NUM_PG_IDENT_FILE_MAPPINGS_ATTS];

  bool    nulls[NUM_PG_IDENT_FILE_MAPPINGS_ATTS];

  HeapTuple tuple;

  int     index;

  Assert(tupdesc->natts == NUM_PG_IDENT_FILE_MAPPINGS_ATTS);

  memset(values, 0, sizeof(values));

  memset(nulls, 0, sizeof(nulls));

  index = 0;

  /* map_number, nothing on error */

  if (err_msg)

    nulls[index++] = true;

  else

    values[index++] = Int32GetDatum(map_number);

  /* file_name */

  values[index++] = CStringGetTextDatum(filename);

  /* line_number */

  values[index++] = Int32GetDatum(lineno);

  if (ident != NULL)

  {

    values[index++] = CStringGetTextDatum(ident->usermap);

    values[index++] = CStringGetTextDatum(ident->system_user->string);

    values[index++] = CStringGetTextDatum(ident->pg_user->string);

  }

  else

  {

    /* no parsing result, so set relevant fields to nulls */

    memset(&nulls[3], true, (NUM_PG_IDENT_FILE_MAPPINGS_ATTS - 4) * sizeof(bool));

  }

  /* error */

  if (err_msg)

    values[NUM_PG_IDENT_FILE_MAPPINGS_ATTS - 1] = CStringGetTextDatum(err_msg);

  else

    nulls[NUM_PG_IDENT_FILE_MAPPINGS_ATTS - 1] = true;

  tuple = heap_form_tuple(tupdesc, values, nulls);

  tuplestore_puttuple(tuple_store, tuple);

}

/*

 * Read the pg_ident.conf file and fill the tuplestore with view records.

 */

static void

fill_ident_view(Tuplestorestate *tuple_store, TupleDesc tupdesc)

{

  FILE     *file;

  List     *ident_lines = NIL;

  ListCell   *line;

  int     map_number = 0;

  MemoryContext identcxt;

  MemoryContext oldcxt;

  /*

   * In the unlikely event that we can't open pg_ident.conf, we throw an

   * error, rather than trying to report it via some sort of view entry.

   * (Most other error conditions should result in a message in a view

   * entry.)

   */

  file = open_auth_file(IdentFileName, ERROR, 0, NULL);

  tokenize_auth_file(IdentFileName, file, &ident_lines, DEBUG3, 0);

  /* Now parse all the lines */

  identcxt = AllocSetContextCreate(CurrentMemoryContext,

                   "ident parser context",

                   ALLOCSET_SMALL_SIZES);

  oldcxt = MemoryContextSwitchTo(identcxt);

  foreach(line, ident_lines)

  {

    TokenizedAuthLine *tok_line = (TokenizedAuthLine *) lfirst(line);

    IdentLine  *identline = NULL;

    /* don't parse lines that already have errors */

    if (tok_line->err_msg == NULL)

      identline = parse_ident_line(tok_line, DEBUG3);

    /* no error, set a new mapping number */

    if (tok_line->err_msg == NULL)

      map_number++;

    fill_ident_line(tuple_store, tupdesc, map_number,

            tok_line->file_name, tok_line->line_num,

            identline, tok_line->err_msg);

  }

  /* Free tokenizer memory */

  free_auth_file(file, 0);

  /* Free parse_ident_line memory */

  MemoryContextSwitchTo(oldcxt);

  MemoryContextDelete(identcxt);

}

/*

 * SQL-accessible SRF to return all the entries in the pg_ident.conf file.

 */

Datum

pg_ident_file_mappings(PG_FUNCTION_ARGS)

{

  ReturnSetInfo *rsi;

  /*

   * Build tuplestore to hold the result rows.  We must use the Materialize

   * mode to be safe against HBA file changes while the cursor is open. It's

   * also more efficient than having to look up our current position in the

   * parsed list every time.

   */

  InitMaterializedSRF(fcinfo, 0);

  /* Fill the tuplestore */

  rsi = (ReturnSetInfo *) fcinfo->resultinfo;

  fill_ident_view(rsi->setResult, rsi->setDesc);

  PG_RETURN_NULL();

}