Commit work in progress before I get drunk tonight.

Code from sparc64 and NetBSD.

Basically we can link the most, lazy linking works (!), but something else
is screwed.

1 files changed, 314 insertions, 8 deletions

diff --git a/libexec/ld.so/sparc/rtld_machine.c b/libexec/ld.so/sparc/rtld_machine.c
index 546e8c40fe7..2ff19519864 100644
--- a/libexec/ld.so/sparc/rtld_machine.c
+++ b/libexec/ld.so/sparc/rtld_machine.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rtld_machine.c,v 1.1 2002/07/27 13:19:26 art Exp $ */
+/*	$OpenBSD: rtld_machine.c,v 1.2 2002/07/27 16:56:01 art Exp $ */
 
 /*
  * Copyright (c) 1999 Dale Rahn
@@ -57,26 +57,332 @@ _dl_bcopy(const void *src, void *dest, int size)
 		pdest[i] = psrc[i];
 }
 
+/*
+ * The following table holds for each relocation type:
+ *	- the width in bits of the memory location the relocation
+ *	  applies to (not currently used)
+ *	- the number of bits the relocation value must be shifted to the
+ *	  right (i.e. discard least significant bits) to fit into
+ *	  the appropriate field in the instruction word.
+ *	- flags indicating whether
+ *		* the relocation involves a symbol
+ *		* the relocation is relative to the current position
+ *		* the relocation is for a GOT entry
+ *		* the relocation is relative to the load address
+ *
+ */
+#define _RF_S		0x80000000		/* Resolve symbol */
+#define _RF_A		0x40000000		/* Use addend */
+#define _RF_P		0x20000000		/* Location relative */
+#define _RF_G		0x10000000		/* GOT offset */
+#define _RF_B		0x08000000		/* Load address relative */
+#define _RF_SZ(s)	(((s) & 0xff) << 8)	/* memory target size */
+#define _RF_RS(s)	((s) & 0xff)		/* right shift */
+static int reloc_target_flags[] = {
+	0,							/* NONE */
+	_RF_S|_RF_A|		_RF_SZ(8)  | _RF_RS(0),		/* RELOC_8 */
+	_RF_S|_RF_A|		_RF_SZ(16) | _RF_RS(0),		/* RELOC_16 */
+	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* RELOC_32 */
+	_RF_S|_RF_A|_RF_P|	_RF_SZ(8)  | _RF_RS(0),		/* DISP_8 */
+	_RF_S|_RF_A|_RF_P|	_RF_SZ(16) | _RF_RS(0),		/* DISP_16 */
+	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(0),		/* DISP_32 */
+	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(2),		/* WDISP_30 */
+	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(2),		/* WDISP_22 */
+	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(10),	/* HI22 */
+	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* 22 */
+	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* 13 */
+	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* LO10 */
+	_RF_G|			_RF_SZ(32) | _RF_RS(0),		/* GOT10 */
+	_RF_G|			_RF_SZ(32) | _RF_RS(0),		/* GOT13 */
+	_RF_G|			_RF_SZ(32) | _RF_RS(10),	/* GOT22 */
+	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(0),		/* PC10 */
+	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(10),	/* PC22 */
+	      _RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(2),		/* WPLT30 */
+				_RF_SZ(32) | _RF_RS(0),		/* COPY */
+	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* GLOB_DAT */
+				_RF_SZ(32) | _RF_RS(0),		/* JMP_SLOT */
+	      _RF_A|	_RF_B|	_RF_SZ(32) | _RF_RS(0),		/* RELATIVE */
+	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* UA_32 */
+
+	/*unknown*/		_RF_SZ(32) | _RF_RS(0),		/* PLT32 */
+	/*unknown*/		_RF_SZ(32) | _RF_RS(0),		/* HIPLT22 */
+	/*unknown*/		_RF_SZ(32) | _RF_RS(0),		/* LOPLT10 */
+	/*unknown*/		_RF_SZ(32) | _RF_RS(0),		/* LOPLT10 */
+	/*unknown*/		_RF_SZ(32) | _RF_RS(0),		/* PCPLT22 */
+	/*unknown*/		_RF_SZ(32) | _RF_RS(0),		/* PCPLT32 */
+	_RF_S|_RF_A|/*unknown*/	_RF_SZ(32) | _RF_RS(0),		/* 10 */
+	_RF_S|_RF_A|/*unknown*/	_RF_SZ(32) | _RF_RS(0),		/* 11 */
+	_RF_S|_RF_A|/*unknown*/	_RF_SZ(32) | _RF_RS(0),		/* 64 */
+	_RF_S|_RF_A|/*unknown*/	_RF_SZ(32) | _RF_RS(0),		/* OLO10 */
+	_RF_S|_RF_A|/*unknown*/	_RF_SZ(32) | _RF_RS(0),		/* HH22 */
+	_RF_S|_RF_A|/*unknown*/	_RF_SZ(32) | _RF_RS(0),		/* HM10 */
+	_RF_S|_RF_A|/*unknown*/	_RF_SZ(32) | _RF_RS(0),		/* LM22 */
+	_RF_S|_RF_A|_RF_P|/*unknown*/	_RF_SZ(32) | _RF_RS(0),	/* WDISP16 */
+	_RF_S|_RF_A|_RF_P|/*unknown*/	_RF_SZ(32) | _RF_RS(0),	/* WDISP19 */
+	/*unknown*/		_RF_SZ(32) | _RF_RS(0),		/* GLOB_JMP */
+	/*unknown*/		_RF_SZ(32) | _RF_RS(0),		/* 7 */
+	/*unknown*/		_RF_SZ(32) | _RF_RS(0),		/* 5 */
+	/*unknown*/		_RF_SZ(32) | _RF_RS(0),		/* 6 */
+};
+
+#define RELOC_RESOLVE_SYMBOL(t)		((reloc_target_flags[t] & _RF_S) != 0)
+#define RELOC_PC_RELATIVE(t)		((reloc_target_flags[t] & _RF_P) != 0)
+#define RELOC_BASE_RELATIVE(t)		((reloc_target_flags[t] & _RF_B) != 0)
+#define RELOC_USE_ADDEND(t)		((reloc_target_flags[t] & _RF_A) != 0)
+#define RELOC_TARGET_SIZE(t)		((reloc_target_flags[t] >> 8) & 0xff)
+#define RELOC_VALUE_RIGHTSHIFT(t)	(reloc_target_flags[t] & 0xff)
+
+static int reloc_target_bitmask[] = {
+#define _BM(x)	(~(-(1ULL << (x))))
+	0,				/* NONE */
+	_BM(8), _BM(16), _BM(32),	/* RELOC_8, _16, _32 */
+	_BM(8), _BM(16), _BM(32),	/* DISP8, DISP16, DISP32 */
+	_BM(30), _BM(22),		/* WDISP30, WDISP22 */
+	_BM(22), _BM(22),		/* HI22, _22 */
+	_BM(13), _BM(10),		/* RELOC_13, _LO10 */
+	_BM(10), _BM(13), _BM(22),	/* GOT10, GOT13, GOT22 */
+	_BM(10), _BM(22),		/* _PC10, _PC22 */
+	_BM(30), 0,			/* _WPLT30, _COPY */
+	-1, -1, -1,			/* _GLOB_DAT, JMP_SLOT, _RELATIVE */
+	_BM(32), _BM(32),		/* _UA32, PLT32 */
+	_BM(22), _BM(10),		/* _HIPLT22, LOPLT10 */
+	_BM(32), _BM(22), _BM(10),	/* _PCPLT32, _PCPLT22, _PCPLT10 */
+	_BM(10), _BM(11), -1,		/* _10, _11, _64 */
+	_BM(10), _BM(22),		/* _OLO10, _HH22 */
+	_BM(10), _BM(22),		/* _HM10, _LM22 */
+	_BM(16), _BM(19),		/* _WDISP16, _WDISP19 */
+	-1,				/* GLOB_JMP */
+	_BM(7), _BM(5), _BM(6)		/* _7, _5, _6 */
+#undef _BM
+};
+#define RELOC_VALUE_BITMASK(t)	(reloc_target_bitmask[t])
+
+void _dl_reloc_plt(Elf_Word *where, Elf_Addr value);
+
 int
 _dl_md_reloc(elf_object_t *object, int rel, int relasz)
 {
-	return (0);
+	long	i;
+	long	numrela;
+	long	fails = 0;
+	Elf_Addr loff;
+	Elf_RelA *relas;
+	struct load_list *llist;
+
+	loff = object->load_offs;
+	numrela = object->Dyn.info[relasz] / sizeof(Elf_RelA);
+	relas = (Elf_RelA *)(object->Dyn.info[rel]);
+
+	if (relas == NULL)
+		return(0);
+
+	/*
+	 * unprotect some segments if we need it.
+	 */
+	if ((rel == DT_REL || rel == DT_RELA)) {
+		for (llist = object->load_list; llist != NULL; llist = llist->next) {
+			if (!(llist->prot & PROT_WRITE))
+				_dl_mprotect(llist->start, llist->size,
+				    llist->prot|PROT_WRITE);
+		}
+	}
+
+	for (i = 0; i < numrela; i++, relas++) {
+		Elf_Addr *where, value, ooff, mask;
+		Elf_Word type;
+		const Elf_Sym *sym, *this;
+		const char *symn;
+
+		type = ELF_R_TYPE(relas->r_info);
+
+		if (type == R_TYPE(NONE))
+			continue;
+
+		if (type == R_TYPE(JMP_SLOT) && rel != DT_JMPREL)
+			continue;
+
+		where = (Elf_Addr *)(relas->r_offset + loff);
+
+		if (RELOC_USE_ADDEND(type))
+			value = relas->r_addend;
+		else
+			value = 0;
+
+		sym = NULL;
+		symn = NULL;
+		if (RELOC_RESOLVE_SYMBOL(type)) {
+			sym = object->dyn.symtab;
+			sym += ELF_R_SYM(relas->r_info);
+			symn = object->dyn.strtab + sym->st_name;
+
+			if (sym->st_shndx != SHN_UNDEF &&
+			    ELF_ST_BIND(sym->st_info) == STB_LOCAL) {
+				value += loff;
+			} else {
+				this = NULL;
+				ooff = _dl_find_symbol(symn, _dl_objects,
+				    &this, 0, 1);
+				if (this == NULL) {
+resolve_failed:
+					_dl_printf("%s: %s: can't resolve "
+					    "reference '%s'\n",
+					    _dl_progname, object->load_name,
+					    symn);
+					fails++;
+					continue;
+				}
+				value += (Elf_Addr)(ooff + this->st_value);
+#ifdef notyet
+/*
+ * XXX Hmm, we should change the API of _dl_find_symbol and do this in there,
+ * XXX or maybe make a wrapper.
+ */
+				if (this->st_size != sym->st_size &&
+				    sym->st_size != 0) {
+					_dl_printf("%s: %s : WARNING: "
+					    "symbol(%s) size mismatch ",
+					    _dl_progname, object->load_name,
+					    symn);
+					_dl_printf("relink your program\n");
+				}
+#endif
+			}
+		}
+
+		if (type == R_TYPE(JMP_SLOT)) {
+			_dl_reloc_plt((Elf_Word *)where, value);
+			continue;
+		}
+
+		if (type == R_TYPE(COPY)) {
+			void *dstaddr = where;
+			const void *srcaddr;
+			const Elf_Sym *dstsym = sym, *srcsym = NULL;
+			size_t size = dstsym->st_size;
+			Elf_Addr soff;
+
+			soff = _dl_find_symbol(symn, object->next, &srcsym,
+				0, 2);
+			if (srcsym == NULL)
+				goto resolve_failed;
+
+			srcaddr = (void *)(soff + srcsym->st_value);
+			_dl_bcopy(srcaddr, dstaddr, size);
+			continue;
+		}
+
+		if (RELOC_PC_RELATIVE(type))
+			value -= (Elf_Addr)where;
+		if (RELOC_BASE_RELATIVE(type))
+			value += loff + *where;
+
+		mask = RELOC_VALUE_BITMASK(type);
+		value >>= RELOC_VALUE_RIGHTSHIFT(type);
+		value &= mask;
+
+		/* We ignore alignment restrictions here */
+		*where &= ~mask;
+		*where |= value;
+
+	}
+
+	/* reprotect the unprotected segments */
+	if ((rel == DT_REL || rel == DT_RELA)) {
+		for (llist = object->load_list; llist != NULL; llist = llist->next) {
+			if (!(llist->prot & PROT_WRITE))
+				_dl_mprotect(llist->start, llist->size,
+				    llist->prot);
+		}
+	}
+
+	return (fails);
+}
+
+void
+_dl_reloc_plt(Elf_Word *where, Elf_Addr value)
+{
+	/*
+	 * At the PLT entry pointed at by `where', we now construct
+	 * a direct transfer to the now fully resolved function
+	 * address.  The resulting code in the jump slot is:
+	 *
+	 *	sethi	%hi(roffset), %g1
+	 *	sethi	%hi(addr), %g1
+	 *	jmp	%g1+%lo(addr)
+	 *
+	 * We write the third instruction first, since that leaves the
+	 * previous `b,a' at the second word in place. Hence the whole
+	 * PLT slot can be atomically change to the new sequence by
+	 * writing the `sethi' instruction at word 2.
+	 */
+#define SETHI	0x03000000
+#define JMP	0x81c06000
+#define NOP	0x01000000
+	where[2] = JMP   | (value & 0x000003ff);
+	where[1] = SETHI | ((value >> 10) & 0x003fffff);
+	__asm __volatile("iflush %0+8" : : "r" (where));
+	__asm __volatile("iflush %0+4" : : "r" (where));
 }
+
 /*
  * Resolve a symbol at run-time.
  */
 void *
-_dl_bind(elf_object_t *object, int index)
+_dl_bind(elf_object_t *object, Elf_Word reloff)
 {
-	return (NULL);
-}
+	Elf_RelA *rela;
+	Elf_Addr *addr, ooff;
+	const Elf_Sym *sym, *this;
+	const char *symn;
 
-void
-_dl_install_plt(Elf_Word *pltgot, Elf_Addr proc)
-{
+	rela = (Elf_RelA *)(object->Dyn.info[DT_JMPREL] + reloff);
+
+	sym = object->dyn.symtab;
+	sym += ELF_R_SYM(rela->r_info);
+	symn = object->dyn.strtab + sym->st_name;
+
+DL_DEB(("_dl_bind %s\n", symn));
+
+	addr = (Elf_Addr *)(object->load_offs + rela->r_offset);
+	ooff = _dl_find_symbol(symn, _dl_objects, &this, 0, 1);
+	if (this == NULL) {
+		_dl_printf("lazy binding failed!\n");
+		*((int *)0) = 0;	/* XXX */
+	}
+
+	_dl_reloc_plt(addr, ooff + this->st_value);
+
+	return (void *)ooff + this->st_value;
 }
 
 void
 _dl_md_reloc_got(elf_object_t *object, int lazy)
 {
+	Elf_Addr *pltgot;
+	extern void _dl_bind_start(void);	/* XXX */
+
+	pltgot = (Elf_Addr *)object->Dyn.info[DT_PLTGOT];
+
+	if (object->obj_type == OBJTYPE_LDR || !lazy || pltgot == NULL) {
+		_dl_md_reloc(object, DT_JMPREL, DT_PLTRELSZ);
+		return;
+	}
+
+	/*
+	 * PLTGOT is the PLT on the sparc.
+	 * The first entry holds the call the dynamic linker.
+	 * We construct a `call' sequence that transfers
+	 * to `_rtld_bind_start()'.
+	 * The second entry holds the object identification.
+	 * Note: each PLT entry is three words long.
+	 */
+#define SAVE    0x9de3bfc0      /* i.e. `save %sp,-64,%sp' */
+#define CALL    0x40000000
+#define NOP     0x01000000
+	pltgot[0] = SAVE;
+	pltgot[1] = CALL |
+	    ((Elf_Addr)&_dl_bind_start -
+	     (Elf_Addr)&pltgot[1]) >> 2;
+	pltgot[2] = NOP;
+	pltgot[3] = (Elf_Addr) object;
 }