1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate * CDDL HEADER START
3*0Sstevel@tonic-gate *
4*0Sstevel@tonic-gate * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate * (the "License"). You may not use this file except in compliance
7*0Sstevel@tonic-gate * with the License.
8*0Sstevel@tonic-gate *
9*0Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate * and limitations under the License.
13*0Sstevel@tonic-gate *
14*0Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate *
20*0Sstevel@tonic-gate * CDDL HEADER END
21*0Sstevel@tonic-gate */
22*0Sstevel@tonic-gate /*
23*0Sstevel@tonic-gate * Copyright 2003 Sun Microsystems, Inc. All rights reserved.
24*0Sstevel@tonic-gate * Use is subject to license terms.
25*0Sstevel@tonic-gate *
26*0Sstevel@tonic-gate * Binary compatibility ld.so. Intercepts the reference of a pre-SVR4
27*0Sstevel@tonic-gate * SunOS executable to the dynamic linker, and then redirects to the
28*0Sstevel@tonic-gate * "real" post-SVR4 SunOS ld.so.
29*0Sstevel@tonic-gate */
30*0Sstevel@tonic-gate #pragma ident "%Z%%M% %I% %E% SMI"
31*0Sstevel@tonic-gate
32*0Sstevel@tonic-gate /*
33*0Sstevel@tonic-gate * Import data structures (N.B.: from 5.x).
34*0Sstevel@tonic-gate */
35*0Sstevel@tonic-gate #include <sys/types.h>
36*0Sstevel@tonic-gate #include <sys/mman.h>
37*0Sstevel@tonic-gate #include <sys/fcntl.h>
38*0Sstevel@tonic-gate #include <sys/stat.h>
39*0Sstevel@tonic-gate #include <sys/sysconfig.h>
40*0Sstevel@tonic-gate #include <sys/auxv.h>
41*0Sstevel@tonic-gate #include <sys/archsystm.h>
42*0Sstevel@tonic-gate #include <elf.h>
43*0Sstevel@tonic-gate #include <link.h>
44*0Sstevel@tonic-gate
45*0Sstevel@tonic-gate /*
46*0Sstevel@tonic-gate * Relocation manifest constants and macros.
47*0Sstevel@tonic-gate */
48*0Sstevel@tonic-gate #define ALIGN(x, a) ((int)(x) & ~((int)(a) - 1))
49*0Sstevel@tonic-gate #define ROUND(x, a) (((int)(x) + ((int)(a) - 1)) & \
50*0Sstevel@tonic-gate ~((int)(a) - 1))
51*0Sstevel@tonic-gate #define DYNAMIC_VERSION2 2
52*0Sstevel@tonic-gate #define RELOC_SIZE (sizeof (struct relocation_info))
53*0Sstevel@tonic-gate #define RELOCOFF(x) (x)->v2->ld_rel
54*0Sstevel@tonic-gate #define MASK(n) ((1<<(n))-1)
55*0Sstevel@tonic-gate #define IN_RANGE(v, n) ((-(1<<((n)-1))) <= (v) && (v) < (1<<((n)-1)))
56*0Sstevel@tonic-gate
57*0Sstevel@tonic-gate void aout_reloc_write();
58*0Sstevel@tonic-gate
59*0Sstevel@tonic-gate /*
60*0Sstevel@tonic-gate * 4.x SunOS Dynamic Link Editor public definitions (much derived from
61*0Sstevel@tonic-gate * SunOS 4.x <link.h>.)
62*0Sstevel@tonic-gate */
63*0Sstevel@tonic-gate
64*0Sstevel@tonic-gate /*
65*0Sstevel@tonic-gate * Dynamic linking information. With the exception of
66*0Sstevel@tonic-gate * ld_loaded (determined at execution time) and ld_stab_hash (a special
67*0Sstevel@tonic-gate * case of relocation handled at execution time), the values in this
68*0Sstevel@tonic-gate * structure reflect offsets from the containing link_dynamic structure.
69*0Sstevel@tonic-gate */
70*0Sstevel@tonic-gate struct link_dynamic_1 {
71*0Sstevel@tonic-gate struct link_map *ld_loaded; /* list of loaded objects */
72*0Sstevel@tonic-gate long ld_need; /* list of needed objects */
73*0Sstevel@tonic-gate long ld_rules; /* search rules for library objects */
74*0Sstevel@tonic-gate long ld_got; /* global offset table */
75*0Sstevel@tonic-gate long ld_plt; /* procedure linkage table */
76*0Sstevel@tonic-gate long ld_rel; /* relocation table */
77*0Sstevel@tonic-gate long ld_hash; /* symbol hash table */
78*0Sstevel@tonic-gate long ld_stab; /* symbol table itself */
79*0Sstevel@tonic-gate long (*ld_stab_hash)(); /* "pointer" to symbol hash function */
80*0Sstevel@tonic-gate long ld_buckets; /* number of hash buckets */
81*0Sstevel@tonic-gate long ld_symbols; /* symbol strings */
82*0Sstevel@tonic-gate long ld_symb_size; /* size of symbol strings */
83*0Sstevel@tonic-gate long ld_text; /* size of text area */
84*0Sstevel@tonic-gate };
85*0Sstevel@tonic-gate
86*0Sstevel@tonic-gate struct link_dynamic_2 {
87*0Sstevel@tonic-gate struct link_map *ld_loaded; /* list of loaded objects */
88*0Sstevel@tonic-gate long ld_need; /* list of needed objects */
89*0Sstevel@tonic-gate long ld_rules; /* search rules for library objects */
90*0Sstevel@tonic-gate long ld_got; /* global offset table */
91*0Sstevel@tonic-gate long ld_plt; /* procedure linkage table */
92*0Sstevel@tonic-gate long ld_rel; /* relocation table */
93*0Sstevel@tonic-gate long ld_hash; /* symbol hash table */
94*0Sstevel@tonic-gate long ld_stab; /* symbol table itself */
95*0Sstevel@tonic-gate long (*ld_stab_hash)(); /* "pointer" to symbol hash function */
96*0Sstevel@tonic-gate long ld_buckets; /* number of hash buckets */
97*0Sstevel@tonic-gate long ld_symbols; /* symbol strings */
98*0Sstevel@tonic-gate long ld_symb_size; /* size of symbol strings */
99*0Sstevel@tonic-gate long ld_text; /* size of text area */
100*0Sstevel@tonic-gate long ld_plt_sz; /* size of procedure linkage table */
101*0Sstevel@tonic-gate };
102*0Sstevel@tonic-gate
103*0Sstevel@tonic-gate /*
104*0Sstevel@tonic-gate * Debugger interface structure.
105*0Sstevel@tonic-gate */
106*0Sstevel@tonic-gate struct ld_debug {
107*0Sstevel@tonic-gate int ldd_version; /* version # of interface */
108*0Sstevel@tonic-gate int ldd_in_debugger; /* a debugger is running us */
109*0Sstevel@tonic-gate int ldd_sym_loaded; /* we loaded some symbols */
110*0Sstevel@tonic-gate char *ldd_bp_addr; /* place for ld-generated bpt */
111*0Sstevel@tonic-gate int ldd_bp_inst; /* instruction which was there */
112*0Sstevel@tonic-gate struct rtc_symb *ldd_cp; /* commons we built */
113*0Sstevel@tonic-gate };
114*0Sstevel@tonic-gate
115*0Sstevel@tonic-gate /*
116*0Sstevel@tonic-gate * Structure associated with each object which may be or which requires
117*0Sstevel@tonic-gate * execution-time link editing. Used by the run-time linkage editor to
118*0Sstevel@tonic-gate * identify needed objects and symbol definitions and references.
119*0Sstevel@tonic-gate */
120*0Sstevel@tonic-gate struct link_dynamic {
121*0Sstevel@tonic-gate int ld_version;
122*0Sstevel@tonic-gate struct ld_debug *ldd;
123*0Sstevel@tonic-gate union {
124*0Sstevel@tonic-gate struct link_dynamic_1 *ld_1;
125*0Sstevel@tonic-gate struct link_dynamic_2 *ld_2;
126*0Sstevel@tonic-gate } ld_un;
127*0Sstevel@tonic-gate };
128*0Sstevel@tonic-gate
129*0Sstevel@tonic-gate struct old_link_dynamic {
130*0Sstevel@tonic-gate int ld_version; /* version # of this structure */
131*0Sstevel@tonic-gate union {
132*0Sstevel@tonic-gate struct link_dynamic_1 ld_1;
133*0Sstevel@tonic-gate } ld_un;
134*0Sstevel@tonic-gate
135*0Sstevel@tonic-gate int in_debugging;
136*0Sstevel@tonic-gate int sym_loaded;
137*0Sstevel@tonic-gate char *bp_addr;
138*0Sstevel@tonic-gate int bp_inst;
139*0Sstevel@tonic-gate struct rtc_symb *cp; /* pointer to an array of runtime */
140*0Sstevel@tonic-gate /* allocated common symbols. */
141*0Sstevel@tonic-gate };
142*0Sstevel@tonic-gate
143*0Sstevel@tonic-gate #define v2 ld_un.ld_2 /* short hands */
144*0Sstevel@tonic-gate #define v1 ld_un.ld_1
145*0Sstevel@tonic-gate
146*0Sstevel@tonic-gate /*
147*0Sstevel@tonic-gate * SunOS 4.x SPARC relocation types and relocation record. Note that
148*0Sstevel@tonic-gate * these, among other things, make this program not portable to things
149*0Sstevel@tonic-gate * other than SPARC.
150*0Sstevel@tonic-gate */
151*0Sstevel@tonic-gate enum reloc_type {
152*0Sstevel@tonic-gate RELOC_8, RELOC_16, RELOC_32, /* simplest relocs */
153*0Sstevel@tonic-gate RELOC_DISP8, RELOC_DISP16, RELOC_DISP32,
154*0Sstevel@tonic-gate /* Disp's (pc-rel) */
155*0Sstevel@tonic-gate RELOC_WDISP30, RELOC_WDISP22, /* SR word disp's */
156*0Sstevel@tonic-gate RELOC_HI22, RELOC_22, /* SR 22-bit relocs */
157*0Sstevel@tonic-gate RELOC_13, RELOC_LO10, /* SR 13&10-bit relocs */
158*0Sstevel@tonic-gate RELOC_SFA_BASE, RELOC_SFA_OFF13, /* SR S.F.A. relocs */
159*0Sstevel@tonic-gate RELOC_BASE10, RELOC_BASE13, RELOC_BASE22,
160*0Sstevel@tonic-gate /* PIC GOT references */
161*0Sstevel@tonic-gate RELOC_PC10, RELOC_PC22, /* PIC reference to GOT */
162*0Sstevel@tonic-gate RELOC_JMP_TBL, /* PIC call */
163*0Sstevel@tonic-gate RELOC_SEGOFF16, /* .so offset-in-segment */
164*0Sstevel@tonic-gate RELOC_GLOB_DAT, RELOC_JMP_SLOT, RELOC_RELATIVE,
165*0Sstevel@tonic-gate /* ld.so relocation types */
166*0Sstevel@tonic-gate };
167*0Sstevel@tonic-gate
168*0Sstevel@tonic-gate struct relocation_info {
169*0Sstevel@tonic-gate unsigned long int r_address; /* relocation addr */
170*0Sstevel@tonic-gate unsigned int r_index :24; /* segment index or symbol index */
171*0Sstevel@tonic-gate unsigned int r_extern : 1; /* if F, r_index==SEG#; if T, SYM idx */
172*0Sstevel@tonic-gate int : 2; /* <unused> */
173*0Sstevel@tonic-gate enum reloc_type r_type : 5; /* type of relocation to perform */
174*0Sstevel@tonic-gate long int r_addend; /* addend for relocation value */
175*0Sstevel@tonic-gate };
176*0Sstevel@tonic-gate
177*0Sstevel@tonic-gate /*
178*0Sstevel@tonic-gate * Size of relocations.
179*0Sstevel@tonic-gate */
180*0Sstevel@tonic-gate #define GETRELSZ(x) \
181*0Sstevel@tonic-gate (x->ld_version < 2 ? \
182*0Sstevel@tonic-gate ((struct old_link_dynamic *)x)->v1.ld_hash - \
183*0Sstevel@tonic-gate ((struct old_link_dynamic *)x)->v1.ld_rel : \
184*0Sstevel@tonic-gate (x)->v2->ld_hash - (x)->v2->ld_rel)
185*0Sstevel@tonic-gate
186*0Sstevel@tonic-gate /*
187*0Sstevel@tonic-gate * Interface between crt0 & ld.so.
188*0Sstevel@tonic-gate */
189*0Sstevel@tonic-gate struct crt_i1 {
190*0Sstevel@tonic-gate int crt_baseaddr; /* Address ld.so is at */
191*0Sstevel@tonic-gate int crt_dzfd; /* /dev/zero file descriptor */
192*0Sstevel@tonic-gate int crt_rlfd; /* ld.so file descriptor */
193*0Sstevel@tonic-gate struct link_dynamic *crt_udp; /* "main_" dynamic */
194*0Sstevel@tonic-gate char **crt_ep; /* environment strings */
195*0Sstevel@tonic-gate caddr_t crt_breakp; /* place to put initial breakpoint */
196*0Sstevel@tonic-gate };
197*0Sstevel@tonic-gate
198*0Sstevel@tonic-gate /*
199*0Sstevel@tonic-gate * Structure we provide to ELF ld.so upon entry.
200*0Sstevel@tonic-gate */
201*0Sstevel@tonic-gate Elf32_Boot eb[EB_MAX];
202*0Sstevel@tonic-gate
203*0Sstevel@tonic-gate /*
204*0Sstevel@tonic-gate * Global data.
205*0Sstevel@tonic-gate */
206*0Sstevel@tonic-gate char *program_name; /* used in messages */
207*0Sstevel@tonic-gate
208*0Sstevel@tonic-gate /*
209*0Sstevel@tonic-gate * 4.0 ld.so main entry point.
210*0Sstevel@tonic-gate */
rtld(version,ip,dp,argp)211*0Sstevel@tonic-gate rtld(version, ip, dp, argp)
212*0Sstevel@tonic-gate int version; /* interface version */
213*0Sstevel@tonic-gate struct crt_i1 *ip; /* interface passed from program */
214*0Sstevel@tonic-gate register struct link_dynamic *dp; /* ld.so dynamic pointer */
215*0Sstevel@tonic-gate caddr_t argp; /* pointer to begining of args */
216*0Sstevel@tonic-gate {
217*0Sstevel@tonic-gate char *ldso; /* name of what we really want to be */
218*0Sstevel@tonic-gate int i, p; /* working */
219*0Sstevel@tonic-gate int r; /* working (# of *our* relocations */
220*0Sstevel@tonic-gate int page_size = 0; /* size of a page */
221*0Sstevel@tonic-gate struct relocation_info *rp; /* working pointer to our relocs */
222*0Sstevel@tonic-gate int fd; /* fd assigned to ld.so */
223*0Sstevel@tonic-gate Elf32_Ehdr *ehdr; /* ELF header of ld.so */
224*0Sstevel@tonic-gate Elf32_Phdr *phdr; /* first Phdr in file */
225*0Sstevel@tonic-gate Elf32_Phdr *pptr; /* working Phdr */
226*0Sstevel@tonic-gate Elf32_Phdr *lph; /* last loadable Phdr */
227*0Sstevel@tonic-gate Elf32_Phdr *fph = 0; /* first loadable Phdr */
228*0Sstevel@tonic-gate caddr_t maddr; /* pointer to mapping claim */
229*0Sstevel@tonic-gate Elf32_Off mlen; /* total mapping claim */
230*0Sstevel@tonic-gate caddr_t faddr; /* first program mapping of ld.so */
231*0Sstevel@tonic-gate Elf32_Off foff; /* file offset for segment mapping */
232*0Sstevel@tonic-gate Elf32_Off flen; /* file length for segment mapping */
233*0Sstevel@tonic-gate caddr_t addr; /* working mapping address */
234*0Sstevel@tonic-gate caddr_t zaddr; /* /dev/zero working mapping addr */
235*0Sstevel@tonic-gate Elf32_Boot *ebp; /* communication with ld.so */
236*0Sstevel@tonic-gate struct stat sb; /* stat buffer for sizing */
237*0Sstevel@tonic-gate auxv_t *ap; /* working aux pointer */
238*0Sstevel@tonic-gate void (* wrt)(); /* address of write/iflush routine */
239*0Sstevel@tonic-gate
240*0Sstevel@tonic-gate /*
241*0Sstevel@tonic-gate * ld.so must itself be relocated, take care of this now.
242*0Sstevel@tonic-gate * We can not refer to global data before this step is
243*0Sstevel@tonic-gate * complete. Perform the relocation by stepping over all
244*0Sstevel@tonic-gate * entries in the relocation table and turn them into
245*0Sstevel@tonic-gate * absolute addresses. Note that, in order to avoid invoking
246*0Sstevel@tonic-gate * as yet unrelocated items, we perform the relocation count
247*0Sstevel@tonic-gate * by counting rather than risk invoking subroutine calls
248*0Sstevel@tonic-gate * to intrinsic .div or .mul routines. Note also that we
249*0Sstevel@tonic-gate * assume that there are no symbolic relocations to be
250*0Sstevel@tonic-gate * performed here.
251*0Sstevel@tonic-gate */
252*0Sstevel@tonic-gate dp->v2 = (struct link_dynamic_2 *)
253*0Sstevel@tonic-gate ((caddr_t)dp->v2 + ip->crt_baseaddr);
254*0Sstevel@tonic-gate r = 0;
255*0Sstevel@tonic-gate i = GETRELSZ(dp);
256*0Sstevel@tonic-gate while (i != 0) {
257*0Sstevel@tonic-gate i -= RELOC_SIZE;
258*0Sstevel@tonic-gate r++;
259*0Sstevel@tonic-gate }
260*0Sstevel@tonic-gate rp = (struct relocation_info *)(RELOCOFF(dp) +
261*0Sstevel@tonic-gate (dp->ld_version < DYNAMIC_VERSION2 ?
262*0Sstevel@tonic-gate (int)dp : ip->crt_baseaddr));
263*0Sstevel@tonic-gate
264*0Sstevel@tonic-gate /*
265*0Sstevel@tonic-gate * Determine the location of the routine that will write the relocation.
266*0Sstevel@tonic-gate * This hasn't yet been relocated so determine the real address using
267*0Sstevel@tonic-gate * our base address.
268*0Sstevel@tonic-gate */
269*0Sstevel@tonic-gate wrt = (void (*)())((caddr_t)aout_reloc_write + ip->crt_baseaddr);
270*0Sstevel@tonic-gate
271*0Sstevel@tonic-gate /*
272*0Sstevel@tonic-gate * Relocate ourselves - we only need RELOC_RELATIVE and RELOC_32.
273*0Sstevel@tonic-gate * Note, if panic() was called its probable that it will barf as the
274*0Sstevel@tonic-gate * corresponding plt wouldn't have been relocated yet.
275*0Sstevel@tonic-gate */
276*0Sstevel@tonic-gate for (i = 0; i < r; i++) {
277*0Sstevel@tonic-gate long *where = (long *)((caddr_t)rp->r_address + ip->crt_baseaddr);
278*0Sstevel@tonic-gate long what = ip->crt_baseaddr;
279*0Sstevel@tonic-gate long value;
280*0Sstevel@tonic-gate
281*0Sstevel@tonic-gate switch (rp->r_type) {
282*0Sstevel@tonic-gate case RELOC_RELATIVE:
283*0Sstevel@tonic-gate what += *where << (32-22);
284*0Sstevel@tonic-gate value = (*where & ~MASK(22)) | ((what >> (32-22)) & MASK(22));
285*0Sstevel@tonic-gate wrt(where, value);
286*0Sstevel@tonic-gate where++;
287*0Sstevel@tonic-gate what += (*where & MASK(10));
288*0Sstevel@tonic-gate value = (*where & ~MASK(10)) | (what & MASK(10));
289*0Sstevel@tonic-gate wrt(where, value);
290*0Sstevel@tonic-gate break;
291*0Sstevel@tonic-gate
292*0Sstevel@tonic-gate case RELOC_32:
293*0Sstevel@tonic-gate what += *where;
294*0Sstevel@tonic-gate wrt(where, what);
295*0Sstevel@tonic-gate break;
296*0Sstevel@tonic-gate
297*0Sstevel@tonic-gate default:
298*0Sstevel@tonic-gate panic("unknown relocation type %d\n", rp->r_type);
299*0Sstevel@tonic-gate break;
300*0Sstevel@tonic-gate }
301*0Sstevel@tonic-gate rp++;
302*0Sstevel@tonic-gate }
303*0Sstevel@tonic-gate
304*0Sstevel@tonic-gate /*
305*0Sstevel@tonic-gate * We're relocated, we can now initialize things referencing
306*0Sstevel@tonic-gate * static storage.
307*0Sstevel@tonic-gate */
308*0Sstevel@tonic-gate ldso = "/usr/lib/ld.so.1";
309*0Sstevel@tonic-gate
310*0Sstevel@tonic-gate /*
311*0Sstevel@tonic-gate * Close off the file descriptor used to get us here -- let it
312*0Sstevel@tonic-gate * be available for the next (probable) use below.
313*0Sstevel@tonic-gate */
314*0Sstevel@tonic-gate (void) close(ip->crt_rlfd);
315*0Sstevel@tonic-gate
316*0Sstevel@tonic-gate /*
317*0Sstevel@tonic-gate * Discover things about our environment: auxiliary vector (if
318*0Sstevel@tonic-gate * any), arguments, program name, and the like.
319*0Sstevel@tonic-gate */
320*0Sstevel@tonic-gate ebp = eb;
321*0Sstevel@tonic-gate program_name = (char *)(argp + sizeof (int));
322*0Sstevel@tonic-gate if (version != 1)
323*0Sstevel@tonic-gate panic("bad startup interface version of %d",
324*0Sstevel@tonic-gate version);
325*0Sstevel@tonic-gate ebp->eb_tag = EB_DYNAMIC,
326*0Sstevel@tonic-gate (ebp++)->eb_un.eb_ptr = (Elf32_Addr)ip->crt_udp;
327*0Sstevel@tonic-gate ebp->eb_tag = EB_ARGV, (ebp++)->eb_un.eb_ptr = (Elf32_Addr)program_name;
328*0Sstevel@tonic-gate ebp->eb_tag = EB_ENVP, (ebp++)->eb_un.eb_ptr = (Elf32_Addr)ip->crt_ep;
329*0Sstevel@tonic-gate ebp->eb_tag = EB_DEVZERO,
330*0Sstevel@tonic-gate (ebp++)->eb_un.eb_val = (Elf32_Word)ip->crt_dzfd;
331*0Sstevel@tonic-gate for (addr = (caddr_t)ip->crt_ep; *addr; addr += sizeof (char *))
332*0Sstevel@tonic-gate ;
333*0Sstevel@tonic-gate addr += sizeof (char *);
334*0Sstevel@tonic-gate
335*0Sstevel@tonic-gate /*
336*0Sstevel@tonic-gate * The kernel sends us an abbreviated aux vector with some
337*0Sstevel@tonic-gate * potentially handy stuff that saves us on syscalls.
338*0Sstevel@tonic-gate *
339*0Sstevel@tonic-gate * Notes on 1226113
340*0Sstevel@tonic-gate *
341*0Sstevel@tonic-gate * The f77 compiler shipped as part of SC1.0 on 4.x creates binaries
342*0Sstevel@tonic-gate * that use the _fix_libc_ feature of acc. This makes the resulting
343*0Sstevel@tonic-gate * executable object dependent on the undocumented behaviour of
344*0Sstevel@tonic-gate * libc's .rem and .div routines e.g. that .div returns the
345*0Sstevel@tonic-gate * remainder in %o3 (and similarly .rem returns the division in %o3).
346*0Sstevel@tonic-gate *
347*0Sstevel@tonic-gate * The only simple solution is to disable hardware divide for
348*0Sstevel@tonic-gate * all 4.x applications so that the old software routines that have
349*0Sstevel@tonic-gate * this "support" in them are used instead. And we do that by
350*0Sstevel@tonic-gate * clearing the divide-in-hardware flag from the aux vector before
351*0Sstevel@tonic-gate * libc's .init routine gets to see it. Awful isn't it.
352*0Sstevel@tonic-gate */
353*0Sstevel@tonic-gate ebp->eb_tag = EB_AUXV, (ebp++)->eb_un.eb_ptr = (Elf32_Addr)addr;
354*0Sstevel@tonic-gate for (ap = (auxv_t *)addr; ap->a_type != AT_NULL; ap++)
355*0Sstevel@tonic-gate if (ap->a_type == AT_PAGESZ) {
356*0Sstevel@tonic-gate page_size = ap->a_un.a_val;
357*0Sstevel@tonic-gate ebp->eb_tag = EB_PAGESIZE, (ebp++)->eb_un.eb_val =
358*0Sstevel@tonic-gate (Elf32_Word)page_size;
359*0Sstevel@tonic-gate } else if (ap->a_type == AT_SUN_HWCAP)
360*0Sstevel@tonic-gate ap->a_un.a_val &= ~AV_SPARC_HWDIV_32x32;
361*0Sstevel@tonic-gate
362*0Sstevel@tonic-gate /*
363*0Sstevel@tonic-gate * If we didn't get a page size from looking in the auxiliary
364*0Sstevel@tonic-gate * vector, we need to get one now.
365*0Sstevel@tonic-gate */
366*0Sstevel@tonic-gate if (page_size == 0) {
367*0Sstevel@tonic-gate page_size = sysconfig(_CONFIG_PAGESIZE);
368*0Sstevel@tonic-gate ebp->eb_tag = EB_PAGESIZE, (ebp++)->eb_un.eb_val =
369*0Sstevel@tonic-gate (Elf32_Word)page_size;
370*0Sstevel@tonic-gate }
371*0Sstevel@tonic-gate
372*0Sstevel@tonic-gate /*
373*0Sstevel@tonic-gate * Map in the ELF-based ld.so. Note that we're mapping it as
374*0Sstevel@tonic-gate * an ELF database, not as a program -- we just want to walk it's
375*0Sstevel@tonic-gate * data structures. Further mappings will actually establish the
376*0Sstevel@tonic-gate * program in the address space.
377*0Sstevel@tonic-gate */
378*0Sstevel@tonic-gate if ((fd = open(ldso, O_RDONLY)) == -1)
379*0Sstevel@tonic-gate panic("unable to open %s", ldso);
380*0Sstevel@tonic-gate if (fstat(fd, &sb) == -1)
381*0Sstevel@tonic-gate panic("unable to find size of %s", ldso);
382*0Sstevel@tonic-gate ehdr = (Elf32_Ehdr *)mmap(0, sb.st_size, PROT_READ | PROT_EXEC,
383*0Sstevel@tonic-gate MAP_SHARED, fd, 0);
384*0Sstevel@tonic-gate if (ehdr == (Elf32_Ehdr *)-1)
385*0Sstevel@tonic-gate panic("unable to map %s", ldso);
386*0Sstevel@tonic-gate
387*0Sstevel@tonic-gate /*
388*0Sstevel@tonic-gate * Validate the file we're looking at, ensure it has the correct
389*0Sstevel@tonic-gate * ELF structures, such as: ELF magic numbers, coded for SPARC,
390*0Sstevel@tonic-gate * is a ".so", etc.
391*0Sstevel@tonic-gate */
392*0Sstevel@tonic-gate if (ehdr->e_ident[EI_MAG0] != ELFMAG0 ||
393*0Sstevel@tonic-gate ehdr->e_ident[EI_MAG1] != ELFMAG1 ||
394*0Sstevel@tonic-gate ehdr->e_ident[EI_MAG2] != ELFMAG2 ||
395*0Sstevel@tonic-gate ehdr->e_ident[EI_MAG3] != ELFMAG3)
396*0Sstevel@tonic-gate panic("%s is not an ELF file", ldso);
397*0Sstevel@tonic-gate if (ehdr->e_ident[EI_CLASS] != ELFCLASS32 ||
398*0Sstevel@tonic-gate ehdr->e_ident[EI_DATA] != ELFDATA2MSB)
399*0Sstevel@tonic-gate panic("%s has wrong class or data encoding", ldso);
400*0Sstevel@tonic-gate if (ehdr->e_type != ET_DYN)
401*0Sstevel@tonic-gate panic("%s is not a shared object", ldso);
402*0Sstevel@tonic-gate if ((ehdr->e_machine != EM_SPARC) &&
403*0Sstevel@tonic-gate (ehdr->e_machine != EM_SPARC32PLUS))
404*0Sstevel@tonic-gate panic("%s is not a valid SPARC object: e_machine: %x",
405*0Sstevel@tonic-gate ldso, ehdr->e_machine);
406*0Sstevel@tonic-gate if (ehdr->e_version > EV_CURRENT)
407*0Sstevel@tonic-gate panic("%s has bad ELF version of %d", ldso, ehdr->e_version);
408*0Sstevel@tonic-gate
409*0Sstevel@tonic-gate /*
410*0Sstevel@tonic-gate * Point at program headers and start figuring out what to load.
411*0Sstevel@tonic-gate */
412*0Sstevel@tonic-gate phdr = (Elf32_Phdr *)((caddr_t)ehdr + ehdr->e_phoff);
413*0Sstevel@tonic-gate for (p = 0, pptr = phdr; p < (int)ehdr->e_phnum; p++,
414*0Sstevel@tonic-gate pptr = (Elf32_Phdr *)((caddr_t)pptr + ehdr->e_phentsize))
415*0Sstevel@tonic-gate if (pptr->p_type == PT_LOAD) {
416*0Sstevel@tonic-gate if (fph == 0) {
417*0Sstevel@tonic-gate fph = pptr;
418*0Sstevel@tonic-gate } else if (pptr->p_vaddr <= lph->p_vaddr)
419*0Sstevel@tonic-gate panic(
420*0Sstevel@tonic-gate "%s invalid program header - segments out of order", ldso);
421*0Sstevel@tonic-gate lph = pptr;
422*0Sstevel@tonic-gate }
423*0Sstevel@tonic-gate
424*0Sstevel@tonic-gate /*
425*0Sstevel@tonic-gate * We'd better have at least one loadable segment.
426*0Sstevel@tonic-gate */
427*0Sstevel@tonic-gate if (fph == 0)
428*0Sstevel@tonic-gate panic("%s has no loadable segments", ldso);
429*0Sstevel@tonic-gate
430*0Sstevel@tonic-gate /*
431*0Sstevel@tonic-gate * Map enough address space to hold the program (as opposed to the
432*0Sstevel@tonic-gate * file) represented by ld.so. The amount to be assigned is the
433*0Sstevel@tonic-gate * range between the end of the last loadable segment and the
434*0Sstevel@tonic-gate * beginning of the first PLUS the alignment of the first segment.
435*0Sstevel@tonic-gate * mmap() can assign us any page-aligned address, but the relocations
436*0Sstevel@tonic-gate * assume the alignments included in the program header. As an
437*0Sstevel@tonic-gate * optimization, however, let's assume that mmap() will actually
438*0Sstevel@tonic-gate * give us an aligned address -- since if it does, we can save
439*0Sstevel@tonic-gate * an munmap() later on. If it doesn't -- then go try it again.
440*0Sstevel@tonic-gate */
441*0Sstevel@tonic-gate mlen = ROUND((lph->p_vaddr + lph->p_memsz) -
442*0Sstevel@tonic-gate ALIGN(fph->p_vaddr, page_size), page_size);
443*0Sstevel@tonic-gate maddr = (caddr_t)mmap(0, mlen, PROT_READ | PROT_EXEC,
444*0Sstevel@tonic-gate MAP_SHARED, fd, 0);
445*0Sstevel@tonic-gate if (maddr == (caddr_t)-1)
446*0Sstevel@tonic-gate panic("unable to reserve space for %s", ldso);
447*0Sstevel@tonic-gate faddr = (caddr_t)ROUND(maddr, fph->p_align);
448*0Sstevel@tonic-gate
449*0Sstevel@tonic-gate /*
450*0Sstevel@tonic-gate * Check to see whether alignment skew was really needed.
451*0Sstevel@tonic-gate */
452*0Sstevel@tonic-gate if (faddr != maddr) {
453*0Sstevel@tonic-gate (void) munmap(maddr, mlen);
454*0Sstevel@tonic-gate mlen = ROUND((lph->p_vaddr + lph->p_memsz) -
455*0Sstevel@tonic-gate ALIGN(fph->p_vaddr, fph->p_align) + fph->p_align,
456*0Sstevel@tonic-gate page_size);
457*0Sstevel@tonic-gate maddr = (caddr_t)mmap(0, mlen, PROT_READ | PROT_EXEC,
458*0Sstevel@tonic-gate MAP_SHARED, fd, 0);
459*0Sstevel@tonic-gate if (maddr == (caddr_t)-1)
460*0Sstevel@tonic-gate panic("unable to reserve space for %s", ldso);
461*0Sstevel@tonic-gate faddr = (caddr_t)ROUND(maddr, fph->p_align);
462*0Sstevel@tonic-gate }
463*0Sstevel@tonic-gate ebp->eb_tag = EB_LDSO_BASE, (ebp++)->eb_un.eb_ptr = (Elf32_Addr)faddr;
464*0Sstevel@tonic-gate
465*0Sstevel@tonic-gate /*
466*0Sstevel@tonic-gate * We have the address space reserved, so map each loadable segment.
467*0Sstevel@tonic-gate */
468*0Sstevel@tonic-gate for (pptr = phdr; (pptr - phdr) < (int)ehdr->e_phnum; pptr++) {
469*0Sstevel@tonic-gate
470*0Sstevel@tonic-gate /*
471*0Sstevel@tonic-gate * Skip non-loadable segments or segments that don't occupy
472*0Sstevel@tonic-gate * any memory.
473*0Sstevel@tonic-gate */
474*0Sstevel@tonic-gate if ((pptr->p_type != PT_LOAD) || (pptr->p_memsz == 0))
475*0Sstevel@tonic-gate continue;
476*0Sstevel@tonic-gate
477*0Sstevel@tonic-gate /*
478*0Sstevel@tonic-gate * Determine the file offset to which the mapping will
479*0Sstevel@tonic-gate * directed (must be aligned) and how much to map (might
480*0Sstevel@tonic-gate * be more than the file in the case of .bss.)
481*0Sstevel@tonic-gate */
482*0Sstevel@tonic-gate foff = ALIGN(pptr->p_offset, page_size);
483*0Sstevel@tonic-gate flen = pptr->p_memsz + (pptr->p_offset - foff);
484*0Sstevel@tonic-gate
485*0Sstevel@tonic-gate /*
486*0Sstevel@tonic-gate * Set address of this segment relative to our base.
487*0Sstevel@tonic-gate */
488*0Sstevel@tonic-gate addr = (caddr_t)ALIGN(faddr + pptr->p_vaddr, page_size);
489*0Sstevel@tonic-gate
490*0Sstevel@tonic-gate /*
491*0Sstevel@tonic-gate * Unmap anything form the last mapping address to this
492*0Sstevel@tonic-gate * one.
493*0Sstevel@tonic-gate */
494*0Sstevel@tonic-gate if (addr - maddr) {
495*0Sstevel@tonic-gate (void) munmap(maddr, addr - maddr);
496*0Sstevel@tonic-gate mlen -= addr - maddr;
497*0Sstevel@tonic-gate }
498*0Sstevel@tonic-gate
499*0Sstevel@tonic-gate /*
500*0Sstevel@tonic-gate * Determine the mapping protection from the section
501*0Sstevel@tonic-gate * attributes.
502*0Sstevel@tonic-gate */
503*0Sstevel@tonic-gate i = 0;
504*0Sstevel@tonic-gate if (pptr->p_flags & PF_R)
505*0Sstevel@tonic-gate i |= PROT_READ;
506*0Sstevel@tonic-gate if (pptr->p_flags & PF_W)
507*0Sstevel@tonic-gate i |= PROT_WRITE;
508*0Sstevel@tonic-gate if (pptr->p_flags & PF_X)
509*0Sstevel@tonic-gate i |= PROT_EXEC;
510*0Sstevel@tonic-gate if ((caddr_t)mmap((caddr_t)addr, flen, i,
511*0Sstevel@tonic-gate MAP_FIXED | MAP_PRIVATE, fd, foff) == (caddr_t)-1)
512*0Sstevel@tonic-gate panic("unable to map a segment from %s", ldso);
513*0Sstevel@tonic-gate
514*0Sstevel@tonic-gate /*
515*0Sstevel@tonic-gate * If the memory occupancy of the segment overflows the
516*0Sstevel@tonic-gate * definition in the file, we need to "zero out" the
517*0Sstevel@tonic-gate * end of the mapping we've established, and if necessary,
518*0Sstevel@tonic-gate * map some more space from /dev/zero.
519*0Sstevel@tonic-gate */
520*0Sstevel@tonic-gate if (pptr->p_memsz > pptr->p_filesz) {
521*0Sstevel@tonic-gate foff = (int)faddr + pptr->p_vaddr + pptr->p_filesz;
522*0Sstevel@tonic-gate zaddr = (caddr_t)ROUND(foff, page_size);
523*0Sstevel@tonic-gate _zero(foff, zaddr - foff);
524*0Sstevel@tonic-gate r = (faddr + pptr->p_vaddr + pptr->p_memsz) - zaddr;
525*0Sstevel@tonic-gate if (r > 0)
526*0Sstevel@tonic-gate if ((caddr_t)mmap((caddr_t)zaddr, r, i,
527*0Sstevel@tonic-gate MAP_FIXED | MAP_PRIVATE, ip->crt_dzfd,
528*0Sstevel@tonic-gate 0) == (caddr_t)-1)
529*0Sstevel@tonic-gate panic(
530*0Sstevel@tonic-gate "unable to map .bss /dev/zero for %s",
531*0Sstevel@tonic-gate ldso);
532*0Sstevel@tonic-gate }
533*0Sstevel@tonic-gate
534*0Sstevel@tonic-gate /*
535*0Sstevel@tonic-gate * Update the mapping claim pointer.
536*0Sstevel@tonic-gate */
537*0Sstevel@tonic-gate maddr = addr + ROUND(flen, page_size);
538*0Sstevel@tonic-gate mlen -= maddr - addr;
539*0Sstevel@tonic-gate }
540*0Sstevel@tonic-gate
541*0Sstevel@tonic-gate /*
542*0Sstevel@tonic-gate * Unmap any final reservation.
543*0Sstevel@tonic-gate */
544*0Sstevel@tonic-gate if (mlen > 0)
545*0Sstevel@tonic-gate (void) munmap(maddr, mlen);
546*0Sstevel@tonic-gate
547*0Sstevel@tonic-gate /*
548*0Sstevel@tonic-gate * Clean up file descriptor space we've consumed. Pass along
549*0Sstevel@tonic-gate * the /dev/zero file descriptor we got -- every cycle counts.
550*0Sstevel@tonic-gate */
551*0Sstevel@tonic-gate (void) close(fd);
552*0Sstevel@tonic-gate
553*0Sstevel@tonic-gate /*
554*0Sstevel@tonic-gate * The call itself. Note that we start 1 instruction word in.
555*0Sstevel@tonic-gate * The ELF ld.so contains an "entry vector" of branch instructions,
556*0Sstevel@tonic-gate * which, for our interest are:
557*0Sstevel@tonic-gate * +0: ba, a <normal startup>
558*0Sstevel@tonic-gate * +4: ba, a <compatibility startup>
559*0Sstevel@tonic-gate * By starting at the compatibility startup, the ELF ld.so knows
560*0Sstevel@tonic-gate * that a pointer to "eb" is available to it and further knows
561*0Sstevel@tonic-gate * how to calculate the offset to the program's arguments and
562*0Sstevel@tonic-gate * other structures.
563*0Sstevel@tonic-gate */
564*0Sstevel@tonic-gate ebp->eb_tag = EB_NULL, ebp->eb_un.eb_val = 0;
565*0Sstevel@tonic-gate (*((void (*)())(ehdr->e_entry + faddr + sizeof (long))))(eb);
566*0Sstevel@tonic-gate return (0);
567*0Sstevel@tonic-gate }
568