Date: Mon, 17 May 2004 12:43:50 -0500 (CDT) From: Dan Nelson <dnelson@allantgroup.com> To: FreeBSD-gnats-submit@FreeBSD.org Subject: bin/66769: [PATCH] more flexible libmap matching rules Message-ID: <200405171743.i4HHho3S043920@dan.emsphone.com> Resent-Message-ID: <200405171750.i4HHoAW4095836@freefall.freebsd.org>
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>Number: 66769
>Category: bin
>Synopsis: [PATCH] more flexible libmap matching rules
>Confidential: no
>Severity: non-critical
>Priority: low
>Responsible: freebsd-bugs
>State: open
>Quarter:
>Keywords:
>Date-Required:
>Class: change-request
>Submitter-Id: current-users
>Arrival-Date: Mon May 17 10:50:10 PDT 2004
>Closed-Date:
>Last-Modified:
>Originator: Dan Nelson
>Release: FreeBSD 5.2-CURRENT i386
>Organization:
>Environment:
System: FreeBSD dan.emsphone.com 5.2-CURRENT FreeBSD 5.2-CURRENT #329: Wed May 12 01:05:37 CDT 2004 dan@dan.emsphone.com:/usr/src/sys/i386/compile/DANSMP i386
>Description:
Allows three matching styles for libmap.conf:
[progname] matches all executables whose basename is 'progname'
[/usr/local/bin/] matches all executables under /usr/local/bin/
[/usr/bin/ls] matches only this executable (note ./ls and
/usr/bin/./ls will not match)
The current libmap code only supports the third style, which is also
the least useful .
>How-To-Repeat:
>Fix:
Index: /usr/src/share/man/man5/libmap.conf.5
===================================================================
RCS file: /home/ncvs/src/share/man/man5/libmap.conf.5,v
retrieving revision 1.5
diff -u -p -r1.5 libmap.conf.5
--- /usr/src/share/man/man5/libmap.conf.5 31 Jan 2004 22:02:03 -0000 1.5
+++ /usr/src/share/man/man5/libmap.conf.5 17 May 2004 17:38:20 -0000
@@ -46,14 +46,44 @@ Dependencies are matched against candida
Constrained mappings may be specified by enclosing the name of the
executable or library in brackets.
All mappings following a constraint will only be evaluated for that constraint.
-Currently, constraints
-are matched literally so that an executable with a fully qualified pathname
-will only match the same constraint.
-This means that
+Constraints can be one of three types:
+.Bl -tag -width indent
+.It Exact
+The constraint is matched literally so that only an executable with an
+identical fully qualified pathname will match the constraint.
+This means that the executable
.Pa /usr/bin/foo
will not match a constraint for
-.Pa foo
+.Pa /usr/bin/./foo
and vise-versa.
+This is the default constraint type.
+.It Basename
+A constraint with no path is matched against the basename of the
+executable.
+.Pa foo
+will match
+.Pa /bin/foo ,
+.Pa /usr/local/sbin/foo ,
+or any other executable named
+.Pa foo ,
+no matter what its path is.
+.It Directory
+A constraint with a trailing slash is prefix-matched against the full
+pathname of the executable.
+.Pa /usr/bin/
+will match any executable with a path starting with /usr/bin.
+.El
+.Pp
+Note that the executable path matched against is the
+.Pa path
+parameter in an
+.Fn exec*
+function call.
+The Directory or Exact constraints can only match when the executable
+is called with a full pathname.
+Most programs executed from a shell are run without a full path, via
+.Fn exec*p ,
+so the Basename constraint type is the most useful.
.Pp
WARNING!
Constrained mappings must never appear first in the configuration file.
@@ -77,19 +107,17 @@ libpthread.so libpthread.so
libc_r.so.5 libpthread.so.1 # Everything that uses 'libc_r'
libc_r.so libpthread.so # now uses 'libpthread'
-[/usr/local/bin/mplayer] # 'mplayer' uses libc_r.
-libpthread.so.1 libc_r.so.5
-libpthread.so libc_r.so
-
-[mplayer]
+[/tmp/mplayer] # Test version of mplayer uses libc_r
libpthread.so.1 libc_r.so.5
libpthread.so libc_r.so
-[/usr/local/sbin/httpd] # Apache uses libthr
-libpthread.so.1 libthr.so.1
-libpthread.so libthr.so
+[mplayer] # All other mplayers use libpthread
+libpthread.so.1 libpthread.so.1
+libpthread.so libpthread.so
-[httpd]
+[/usr/local/jdk1.4.1/] # All Java 1.4.1 programs use libthr
+ # This works because "javavms" executes
+ # programs with the full pathname
libpthread.so.1 libthr.so.1
libpthread.so libthr.so
.Ed
Index: /usr/src/libexec/rtld-elf/libmap.c
===================================================================
RCS file: /home/ncvs/src/libexec/rtld-elf/libmap.c,v
retrieving revision 1.11
diff -u -p -r1.11 libmap.c
--- /usr/src/libexec/rtld-elf/libmap.c 21 Mar 2004 01:21:26 -0000 1.11
+++ /usr/src/libexec/rtld-elf/libmap.c 14 Apr 2004 21:35:19 -0000
@@ -33,6 +33,7 @@ struct lm {
TAILQ_HEAD(lmp_list, lmp) lmp_head = TAILQ_HEAD_INITIALIZER(lmp_head);
struct lmp {
char *p;
+ enum { T_EXACT=0, T_BASENAME, T_DIRECTORY } type;
struct lm_list lml;
TAILQ_ENTRY(lmp) lmp_link;
};
@@ -42,6 +43,7 @@ static void lm_free (struct lm_list *)
static char * lml_find (struct lm_list *, const char *);
static struct lm_list * lmp_find (const char *);
static struct lm_list * lmp_init (char *);
+static const char * quickbasename (const char *);
#define iseol(c) (((c) == '#') || ((c) == '\0') || \
((c) == '\n') || ((c) == '\r'))
@@ -216,6 +218,8 @@ lm_find (const char *p, const char *f)
return (NULL);
}
+/* Given a libmap translation list and a library name, return the
+ replacement library, or NULL */
#ifdef COMPAT_32BIT
char *
lm_findn (const char *p, const char *f, const int n)
@@ -250,6 +254,8 @@ lml_find (struct lm_list *lmh, const cha
return NULL;
}
+/* Given an executable name, return a pointer to the translation list or
+ NULL if no matches */
static struct lm_list *
lmp_find (const char *n)
{
@@ -258,7 +264,9 @@ lmp_find (const char *n)
dbg("%s(\"%s\")", __func__, n);
TAILQ_FOREACH(lmp, &lmp_head, lmp_link)
- if (strcmp(n, lmp->p) == 0)
+ if ((lmp->type == T_EXACT && strcmp(n, lmp->p) == 0) ||
+ (lmp->type == T_DIRECTORY && strncmp(n, lmp->p, strlen(lmp->p)) == 0) ||
+ (lmp->type == T_BASENAME && strcmp(quickbasename(n), lmp->p) == 0))
return (&lmp->lml);
return (NULL);
}
@@ -272,8 +280,28 @@ lmp_init (char *n)
lmp = xmalloc(sizeof(struct lmp));
lmp->p = n;
+ if (n[strlen(n)-1] == '/')
+ lmp->type = T_DIRECTORY;
+ else if (strchr(n,'/') == NULL)
+ lmp->type = T_BASENAME;
+ else
+ lmp->type = T_EXACT;
TAILQ_INIT(&lmp->lml);
TAILQ_INSERT_HEAD(&lmp_head, lmp, lmp_link);
return (&lmp->lml);
}
+
+/* libc basename is overkill. Return a pointer to the character after the
+ last /, or the original string if there are no slashes. */
+static const char *
+quickbasename (const char *path)
+{
+ const char *p = path;
+ for (; *path; path++)
+ {
+ if (*path == '/')
+ p = path+1;
+ }
+ return p;
+}
>Release-Note:
>Audit-Trail:
>Unformatted:
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