3 files changed, 89 insertions, 5 deletions

diff --git a/lib/libc/gen/aux.c b/lib/libc/gen/aux.c
index b5c079bfde564..4bf8643af1664 100644
--- a/lib/libc/gen/aux.c
+++ b/lib/libc/gen/aux.c
@@ -1,5 +1,5 @@
 /*-
- * Copyright 2010 Konstantin Belousov <kib@FreeBSD.ORG>.
+ * Copyright 2010, 2012 Konstantin Belousov <kib@FreeBSD.ORG>.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -36,10 +36,34 @@ __FBSDID("$FreeBSD$");
 #include "un-namespace.h"
 #include "libc_private.h"
 
-Elf_Auxinfo *__elf_aux_vector;
+extern char **environ;
+extern int _DYNAMIC;
+#pragma weak _DYNAMIC
 
-static pthread_once_t aux_once = PTHREAD_ONCE_INIT;
+void *__elf_aux_vector;
+static pthread_once_t aux_vector_once = PTHREAD_ONCE_INIT;
+
+static void
+init_aux_vector_once(void)
+{
+	Elf_Addr *sp;
+
+	sp = (Elf_Addr *)environ;
+	while (*sp++ != 0)
+		;
+	__elf_aux_vector = (Elf_Auxinfo *)sp;
+}
 
+void
+__init_elf_aux_vector(void)
+{
+
+	if (&_DYNAMIC != NULL)
+		return;
+	_once(&aux_vector_once, init_aux_vector_once);
+}
+
+static pthread_once_t aux_once = PTHREAD_ONCE_INIT;
 static int pagesize, osreldate, canary_len, ncpus, pagesizes_len;
 static char *canary, *pagesizes;
 
@@ -86,6 +110,7 @@ _elf_aux_info(int aux, void *buf, int buflen)
 {
 	int res;
 
+	__init_elf_aux_vector();
 	if (__elf_aux_vector == NULL)
 		return (ENOSYS);
 	_once(&aux_once, init_aux);
diff --git a/lib/libc/gen/dlfcn.c b/lib/libc/gen/dlfcn.c
index 7be9f8706f68a..ad24bb4914caf 100644
--- a/lib/libc/gen/dlfcn.c
+++ b/lib/libc/gen/dlfcn.c
@@ -34,6 +34,10 @@ __FBSDID("$FreeBSD$");
 #include <dlfcn.h>
 #include <link.h>
 #include <stddef.h>
+#include "namespace.h"
+#include <pthread.h>
+#include "un-namespace.h"
+#include "libc_private.h"
 
 static char sorry[] = "Service unavailable";
 
@@ -138,13 +142,58 @@ _rtld_thread_init(void * li)
 	_rtld_error(sorry);
 }
 
+static pthread_once_t dl_phdr_info_once = PTHREAD_ONCE_INIT;
+static struct dl_phdr_info phdr_info;
+
+static void
+dl_init_phdr_info(void)
+{
+	Elf_Auxinfo *auxp;
+	size_t phent;
+	unsigned int i;
+
+	phent = 0;
+	for (auxp = __elf_aux_vector; auxp->a_type != AT_NULL; auxp++) {
+		switch (auxp->a_type) {
+		case AT_BASE:
+			phdr_info.dlpi_addr = (Elf_Addr)auxp->a_un.a_ptr;
+			break;
+		case AT_EXECPATH:
+			phdr_info.dlpi_name = (const char *)auxp->a_un.a_ptr;
+			break;
+		case AT_PHDR:
+			phdr_info.dlpi_phdr =
+			    (const Elf_Phdr *)auxp->a_un.a_ptr;
+			break;
+		case AT_PHENT:
+			phent = auxp->a_un.a_val;
+			break;
+		case AT_PHNUM:
+			phdr_info.dlpi_phnum = (Elf_Half)auxp->a_un.a_val;
+			break;
+		}
+	}
+	for (i = 0; i < phdr_info.dlpi_phnum; i++) {
+		if (phdr_info.dlpi_phdr[i].p_type == PT_TLS) {
+			phdr_info.dlpi_tls_modid = 1;
+			phdr_info.dlpi_tls_data =
+			    (void*)phdr_info.dlpi_phdr[i].p_vaddr;
+		}
+	}
+	phdr_info.dlpi_adds = 1;
+}
+
 #pragma weak dl_iterate_phdr
 int
 dl_iterate_phdr(int (*callback)(struct dl_phdr_info *, size_t, void *),
     void *data)
 {
-	_rtld_error(sorry);
-	return 0;
+
+	__init_elf_aux_vector();
+	if (__elf_aux_vector == NULL)
+		return (1);
+	_once(&dl_phdr_info_once, dl_init_phdr_info);
+	return (callback(&phdr_info, sizeof(phdr_info), data));
 }
 
 #pragma weak fdlopen
diff --git a/lib/libc/include/libc_private.h b/lib/libc/include/libc_private.h
index c7284cc3afee1..d4b24a7c962eb 100644
--- a/lib/libc/include/libc_private.h
+++ b/lib/libc/include/libc_private.h
@@ -44,6 +44,15 @@
 extern int	__isthreaded;
 
 /*
+ * Elf_Auxinfo *__elf_aux_vector, the pointer to the ELF aux vector
+ * provided by kernel. Either set for us by rtld, or found at runtime
+ * on stack for static binaries.
+ *
+ * Type is void to avoid polluting whole libc with ELF types.
+ */
+extern void	*__elf_aux_vector;
+
+/*
  * libc should use libc_dlopen internally, which respects a global
  * flag where loading of new shared objects can be restricted.
  */
@@ -229,6 +238,7 @@ int _execvpe(const char *, char * const *, char * const *);
 int _elf_aux_info(int aux, void *buf, int buflen);
 struct dl_phdr_info;
 int __elf_phdr_match_addr(struct dl_phdr_info *, void *);
+void __init_elf_aux_vector(void);
 
 void	_pthread_cancel_enter(int);
 void	_pthread_cancel_leave(int);