[src/trunk]: src/sys - use the unused section in the array to put a NetBSD no...

[christos <christos%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/8c9a959b09cf
branches:  trunk
changeset: 804973:8c9a959b09cf
user:      christos <christos%NetBSD.org@localhost>
date:      Tue Dec 09 02:30:09 2014 +0000

description:
- use the unused section in the array to put a NetBSD note in it
- cleanup the hard-coded constants in the stringtab

diffstat:

 sys/kern/kern_ksyms.c |  57 ++++++++++++++++++++++++++++++++------------------
 sys/sys/ksyms.h       |   7 ++++-
 2 files changed, 41 insertions(+), 23 deletions(-)

diffs (156 lines):

diff -r 1bb6db856a96 -r 8c9a959b09cf sys/kern/kern_ksyms.c
--- a/sys/kern/kern_ksyms.c     Mon Dec 08 20:54:33 2014 +0000
+++ b/sys/kern/kern_ksyms.c     Tue Dec 09 02:30:09 2014 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: kern_ksyms.c,v 1.73 2014/08/17 21:17:44 joerg Exp $    */
+/*     $NetBSD: kern_ksyms.c,v 1.74 2014/12/09 02:30:09 christos Exp $ */
 
 /*-
  * Copyright (c) 2008 The NetBSD Foundation, Inc.
@@ -71,7 +71,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_ksyms.c,v 1.73 2014/08/17 21:17:44 joerg Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_ksyms.c,v 1.74 2014/12/09 02:30:09 christos Exp $");
 
 #if defined(_KERNEL) && defined(_KERNEL_OPT)
 #include "opt_ddb.h"
@@ -843,9 +843,19 @@
 }
 
 static void
+ksyms_fill_note(void)
+{
+       int32_t *note = ksyms_hdr.kh_note;
+       note[0] = ELF_NOTE_NETBSD_NAMESZ;
+       note[1] = ELF_NOTE_NETBSD_DESCSZ;
+       note[2] = ELF_NOTE_TYPE_NETBSD_TAG;
+       memcpy(&note[3],  "NetBSD\0", 8);
+       note[5] = __NetBSD_Version__;
+}
+
+static void
 ksyms_hdr_init(void *hdraddr)
 {
-
        /* Copy the loaded elf exec header */
        memcpy(&ksyms_hdr.kh_ehdr, hdraddr, sizeof(Elf_Ehdr));
 
@@ -863,59 +873,64 @@
        ksyms_hdr.kh_phdr[0].p_memsz = (unsigned long)-1L;
        ksyms_hdr.kh_phdr[0].p_flags = PF_R | PF_X | PF_W;
 
-       /* First section is null */
+#define SHTCOPY(name)  strlcpy(&ksyms_hdr.kh_strtab[offs], (name), \
+    sizeof(ksyms_hdr.kh_strtab) - offs), offs += sizeof(name)
+
+       uint32_t offs = 1;
+       /* First section header ".note.netbsd.ident" */
+       ksyms_hdr.kh_shdr[SHNOTE].sh_name = offs; /* Section 6 offset */
+       ksyms_hdr.kh_shdr[SHNOTE].sh_type = SHT_NOTE;
+       ksyms_hdr.kh_shdr[SHNOTE].sh_offset = 
+           offsetof(struct ksyms_hdr, kh_note[0]);
+       ksyms_hdr.kh_shdr[SHNOTE].sh_size = sizeof(ksyms_hdr.kh_note);
+       ksyms_hdr.kh_shdr[SHNOTE].sh_addralign = sizeof(int);
+       SHTCOPY(".note.netbsd.ident");
+       ksyms_fill_note();
 
        /* Second section header; ".symtab" */
-       ksyms_hdr.kh_shdr[SYMTAB].sh_name = 1; /* Section 3 offset */
+       ksyms_hdr.kh_shdr[SYMTAB].sh_name = offs;
        ksyms_hdr.kh_shdr[SYMTAB].sh_type = SHT_SYMTAB;
        ksyms_hdr.kh_shdr[SYMTAB].sh_offset = sizeof(struct ksyms_hdr);
 /*     ksyms_hdr.kh_shdr[SYMTAB].sh_size = filled in at open */
        ksyms_hdr.kh_shdr[SYMTAB].sh_link = 2; /* Corresponding strtab */
        ksyms_hdr.kh_shdr[SYMTAB].sh_addralign = sizeof(long);
        ksyms_hdr.kh_shdr[SYMTAB].sh_entsize = sizeof(Elf_Sym);
+       SHTCOPY(".symtab");
 
        /* Third section header; ".strtab" */
-       ksyms_hdr.kh_shdr[STRTAB].sh_name = 9; /* Section 3 offset */
+       ksyms_hdr.kh_shdr[STRTAB].sh_name = offs;
        ksyms_hdr.kh_shdr[STRTAB].sh_type = SHT_STRTAB;
 /*     ksyms_hdr.kh_shdr[STRTAB].sh_offset = filled in at open */
 /*     ksyms_hdr.kh_shdr[STRTAB].sh_size = filled in at open */
        ksyms_hdr.kh_shdr[STRTAB].sh_addralign = sizeof(char);
+       SHTCOPY(".strtab");
 
        /* Fourth section, ".shstrtab" */
-       ksyms_hdr.kh_shdr[SHSTRTAB].sh_name = 17; /* This section name offset */
+       ksyms_hdr.kh_shdr[SHSTRTAB].sh_name = offs;
        ksyms_hdr.kh_shdr[SHSTRTAB].sh_type = SHT_STRTAB;
        ksyms_hdr.kh_shdr[SHSTRTAB].sh_offset =
            offsetof(struct ksyms_hdr, kh_strtab);
        ksyms_hdr.kh_shdr[SHSTRTAB].sh_size = SHSTRSIZ;
        ksyms_hdr.kh_shdr[SHSTRTAB].sh_addralign = sizeof(char);
+       SHTCOPY(".shstrtab");
 
        /* Fifth section, ".bss". All symbols reside here. */
-       ksyms_hdr.kh_shdr[SHBSS].sh_name = 27; /* This section name offset */
+       ksyms_hdr.kh_shdr[SHBSS].sh_name = offs;
        ksyms_hdr.kh_shdr[SHBSS].sh_type = SHT_NOBITS;
        ksyms_hdr.kh_shdr[SHBSS].sh_offset = 0;
        ksyms_hdr.kh_shdr[SHBSS].sh_size = (unsigned long)-1L;
        ksyms_hdr.kh_shdr[SHBSS].sh_addralign = PAGE_SIZE;
        ksyms_hdr.kh_shdr[SHBSS].sh_flags = SHF_ALLOC | SHF_EXECINSTR;
+       SHTCOPY(".bss");
 
        /* Sixth section header; ".SUNW_ctf" */
-       ksyms_hdr.kh_shdr[SHCTF].sh_name = 32; /* Section 6 offset */
+       ksyms_hdr.kh_shdr[SHCTF].sh_name = offs;
        ksyms_hdr.kh_shdr[SHCTF].sh_type = SHT_PROGBITS;
 /*     ksyms_hdr.kh_shdr[SHCTF].sh_offset = filled in at open */
 /*     ksyms_hdr.kh_shdr[SHCTF].sh_size = filled in at open */
        ksyms_hdr.kh_shdr[SHCTF].sh_link = SYMTAB; /* Corresponding symtab */
        ksyms_hdr.kh_shdr[SHCTF].sh_addralign = sizeof(char);
-
-       /* Set section names */
-       strlcpy(&ksyms_hdr.kh_strtab[1], ".symtab",
-           sizeof(ksyms_hdr.kh_strtab) - 1);
-       strlcpy(&ksyms_hdr.kh_strtab[9], ".strtab",
-           sizeof(ksyms_hdr.kh_strtab) - 9);
-       strlcpy(&ksyms_hdr.kh_strtab[17], ".shstrtab",
-           sizeof(ksyms_hdr.kh_strtab) - 17);
-       strlcpy(&ksyms_hdr.kh_strtab[27], ".bss",
-           sizeof(ksyms_hdr.kh_strtab) - 27);
-       strlcpy(&ksyms_hdr.kh_strtab[32], ".SUNW_ctf",
-           sizeof(ksyms_hdr.kh_strtab) - 32);
+       SHTCOPY(".SUNW_ctf");
 }
 
 static int
diff -r 1bb6db856a96 -r 8c9a959b09cf sys/sys/ksyms.h
--- a/sys/sys/ksyms.h   Mon Dec 08 20:54:33 2014 +0000
+++ b/sys/sys/ksyms.h   Tue Dec 09 02:30:09 2014 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: ksyms.h,v 1.28 2012/11/18 00:06:56 chs Exp $   */
+/*     $NetBSD: ksyms.h,v 1.29 2014/12/09 02:30:09 christos Exp $      */
 
 /*
  * Copyright (c) 2001, 2003 Anders Magnusson (ragge%ludd.luth.se@localhost).
@@ -58,6 +58,7 @@
  * Static allocated ELF header.
  * Basic info is filled in at attach, sizes at open.
  */
+#define        SHNOTE          0
 #define        SYMTAB          1
 #define        STRTAB          2
 #define        SHSTRTAB        3
@@ -66,13 +67,15 @@
 #define NSECHDR                6
 
 #define        NPRGHDR         1
-#define        SHSTRSIZ        42
+#define        SHSTRSIZ        64
 
 struct ksyms_hdr {
        Elf_Ehdr        kh_ehdr;
        Elf_Phdr        kh_phdr[NPRGHDR];
        Elf_Shdr        kh_shdr[NSECHDR];
        char            kh_strtab[SHSTRSIZ];
+       /* 0=NameSize, 1=DescSize, 2=Tag, 3="NetB", 4="SD\0\0", 5=Version */
+       int32_t         kh_note[6];
 };
 #endif /* _KSYMS_PRIVATE */