Fix a read of uninitialized memory in next_token() of hba.c, spotted via

valgrind: a buffer passed to strncmp() had to be NUL-terminated. Original
report and patch from Dennis Bjorkland, some cleanup by Andrew Dunstan,
and finally some editorializing from Neil Conway.
This commit is contained in:
Neil Conway 2004-02-02 16:58:30 +00:00
parent 4c29e21578
commit 9e218af7ed
2 changed files with 96 additions and 96 deletions

View File

@ -10,7 +10,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/libpq/hba.c,v 1.119 2003/12/25 03:44:04 momjian Exp $
* $PostgreSQL: pgsql/src/backend/libpq/hba.c,v 1.120 2004/02/02 16:58:30 neilc Exp $
*
*-------------------------------------------------------------------------
*/
@ -37,12 +37,23 @@
#include "storage/fd.h"
#define IDENT_USERNAME_MAX 512
/* Max size of username ident server can return */
#define IDENT_USERNAME_MAX 512
/* Standard TCP port number for Ident service. Assigned by IANA */
#define IDENT_PORT 113
/* Name of the config file */
#define CONF_FILE "pg_hba.conf"
/* Name of the usermap file */
#define USERMAP_FILE "pg_ident.conf"
/* This is used to separate values in multi-valued column strings */
#define MULTI_VALUE_SEP "\001"
#define MAX_TOKEN 256
/*
* These variables hold the pre-parsed contents of the hba and ident
* configuration files. Each is a list of sublists, one sublist for
@ -80,19 +91,19 @@ pg_isblank(const char c)
/*
* Grab one token out of fp. Tokens are strings of non-blank
* characters bounded by blank characters, beginning of line, and
* end of line. Blank means space or tab. Return the token as
* *buf. Leave file positioned to character immediately after the
* token or EOF, whichever comes first. If no more tokens on line,
* return null string as *buf and position file to beginning of
* next line or EOF, whichever comes first. Allow spaces in quoted
* strings. Terminate on unquoted commas. Handle comments. Treat
* unquoted keywords that might be user names or database names
* specially, by appending a newline to them.
* Grab one token out of fp. Tokens are strings of non-blank
* characters bounded by blank characters, beginning of line, and
* end of line. Blank means space or tab. Return the token as
* *buf. Leave file positioned at the character immediately after the
* token or EOF, whichever comes first. If no more tokens on line,
* return empty string as *buf and position the file to the beginning
* of the next line or EOF, whichever comes first. Allow spaces in
* quoted strings. Terminate on unquoted commas. Handle
* comments. Treat unquoted keywords that might be user names or
* database names specially, by appending a newline to them.
*/
void
next_token(FILE *fp, char *buf, const int bufsz)
static void
next_token(FILE *fp, char *buf, int bufsz)
{
int c;
char *start_buf = buf;
@ -101,88 +112,89 @@ next_token(FILE *fp, char *buf, const int bufsz)
bool was_quote = false;
bool saw_quote = false;
Assert(end_buf > start_buf);
/* Move over initial whitespace and commas */
while ((c = getc(fp)) != EOF && (pg_isblank(c) || c == ','))
;
if (c != EOF && c != '\n')
if (c == EOF || c == '\n')
{
/*
* Build a token in buf of next characters up to EOF, EOL,
* unquoted comma, or unquoted whitespace.
*/
while (c != EOF && c != '\n' &&
(!pg_isblank(c) || in_quote == true))
*buf = '\0';
return;
}
/*
* Build a token in buf of next characters up to EOF, EOL,
* unquoted comma, or unquoted whitespace.
*/
while (c != EOF && c != '\n' &&
(!pg_isblank(c) || in_quote == true))
{
/* skip comments to EOL */
if (c == '#' && !in_quote)
{
/* skip comments to EOL */
if (c == '#' && !in_quote)
{
while ((c = getc(fp)) != EOF && c != '\n')
;
/* If only comment, consume EOL too; return EOL */
if (c != EOF && buf == start_buf)
c = getc(fp);
break;
}
if (buf >= end_buf)
{
ereport(LOG,
(errcode(ERRCODE_CONFIG_FILE_ERROR),
errmsg("authentication file token too long, skipping: \"%s\"",
buf)));
/* Discard remainder of line */
while ((c = getc(fp)) != EOF && c != '\n')
;
buf[0] = '\0';
break;
}
if (c != '"' || (c == '"' && was_quote))
*buf++ = c;
/* We pass back the comma so the caller knows there is more */
if ((pg_isblank(c) || c == ',') && !in_quote)
break;
/* Literal double-quote is two double-quotes */
if (in_quote && c == '"')
was_quote = !was_quote;
else
was_quote = false;
if (c == '"')
{
in_quote = !in_quote;
saw_quote = true;
}
c = getc(fp);
while ((c = getc(fp)) != EOF && c != '\n')
;
/* If only comment, consume EOL too; return EOL */
if (c != EOF && buf == start_buf)
c = getc(fp);
break;
}
/*
* Put back the char right after the token (critical in case it is
* EOL, since we need to detect end-of-line at next call).
*/
if (c != EOF)
ungetc(c, fp);
if (buf >= end_buf)
{
ereport(LOG,
(errcode(ERRCODE_CONFIG_FILE_ERROR),
errmsg("authentication file token too long, skipping: \"%s\"",
buf)));
/* Discard remainder of line */
while ((c = getc(fp)) != EOF && c != '\n')
;
buf[0] = '\0';
break;
}
if (c != '"' || (c == '"' && was_quote))
*buf++ = c;
/* We pass back the comma so the caller knows there is more */
if ((pg_isblank(c) || c == ',') && !in_quote)
break;
/* Literal double-quote is two double-quotes */
if (in_quote && c == '"')
was_quote = !was_quote;
else
was_quote = false;
if (c == '"')
{
in_quote = !in_quote;
saw_quote = true;
}
c = getc(fp);
}
if ( !saw_quote &&
(
strncmp(start_buf,"all",3) == 0 ||
strncmp(start_buf,"sameuser",8) == 0 ||
strncmp(start_buf,"samegroup",9) == 0
)
)
{
/* append newline to a magical keyword */
*buf++ = '\n';
}
/*
* Put back the char right after the token (critical in case it is
* EOL, since we need to detect end-of-line at next call).
*/
if (c != EOF)
ungetc(c, fp);
*buf = '\0';
if (!saw_quote &&
(strcmp(start_buf, "all") == 0 ||
strcmp(start_buf, "sameuser") == 0 ||
strcmp(start_buf, "samegroup") == 0))
{
/* append newline to a magical keyword */
*buf++ = '\n';
*buf = '\0';
}
}
/*

View File

@ -4,7 +4,7 @@
* Interface to hba.c
*
*
* $PostgreSQL: pgsql/src/include/libpq/hba.h,v 1.34 2003/11/29 22:41:03 pgsql Exp $
* $PostgreSQL: pgsql/src/include/libpq/hba.h,v 1.35 2004/02/02 16:58:30 neilc Exp $
*
*-------------------------------------------------------------------------
*/
@ -17,15 +17,6 @@
#include "nodes/pg_list.h"
#define CONF_FILE "pg_hba.conf"
/* Name of the config file */
#define USERMAP_FILE "pg_ident.conf"
/* Name of the usermap file */
#define IDENT_PORT 113
/* Standard TCP port number for Ident service. Assigned by IANA */
typedef enum UserAuth
{
uaReject,
@ -43,9 +34,6 @@ typedef enum UserAuth
typedef struct Port hbaPort;
#define MAX_TOKEN 256
extern void next_token(FILE *fp, char *buf, const int bufsz);
extern List **get_user_line(const char *user);
extern void load_hba(void);
extern void load_ident(void);