xref: /qemu/bsd-user/netbsd/target_os_elf.h (revision e8f62689acd5930a712655d0c6838ec5eccc6b1c)
1  /*
2   *  netbsd ELF definitions
3   *
4   *  Copyright (c) 2013 Stacey D. Son
5   *
6   *  This program is free software; you can redistribute it and/or modify
7   *  it under the terms of the GNU General Public License as published by
8   *  the Free Software Foundation; either version 2 of the License, or
9   *  (at your option) any later version.
10   *
11   *  This program is distributed in the hope that it will be useful,
12   *  but WITHOUT ANY WARRANTY; without even the implied warranty of
13   *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14   *  GNU General Public License for more details.
15   *
16   *  You should have received a copy of the GNU General Public License
17   *  along with this program; if not, see <http://www.gnu.org/licenses/>.
18   */
19  
20  #ifndef TARGET_OS_ELF_H
21  #define TARGET_OS_ELF_H
22  
23  #include "target_arch_elf.h"
24  #include "elf.h"
25  #include "user/tswap-target.h"
26  
27  /* this flag is uneffective under linux too, should be deleted */
28  #ifndef MAP_DENYWRITE
29  #define MAP_DENYWRITE 0
30  #endif
31  
32  /* should probably go in elf.h */
33  #ifndef ELIBBAD
34  #define ELIBBAD 80
35  #endif
36  
37  #ifndef ELF_PLATFORM
38  #define ELF_PLATFORM (NULL)
39  #endif
40  
41  #ifndef ELF_HWCAP
42  #define ELF_HWCAP 0
43  #endif
44  
45  #ifdef TARGET_ABI32
46  #undef ELF_CLASS
47  #define ELF_CLASS ELFCLASS32
48  #undef bswaptls
49  #define bswaptls(ptr) bswap32s(ptr)
50  #endif
51  
52  /* max code+data+bss space allocated to elf interpreter */
53  #define INTERP_MAP_SIZE (32 * 1024 * 1024)
54  
55  /* max code+data+bss+brk space allocated to ET_DYN executables */
56  #define ET_DYN_MAP_SIZE (128 * 1024 * 1024)
57  
58  /* Necessary parameters */
59  #define TARGET_ELF_EXEC_PAGESIZE TARGET_PAGE_SIZE
60  #define TARGET_ELF_PAGESTART(_v) ((_v) & \
61          ~(unsigned long)(TARGET_ELF_EXEC_PAGESIZE - 1))
62  #define TARGET_ELF_PAGEOFFSET(_v) ((_v) & (TARGET_ELF_EXEC_PAGESIZE - 1))
63  
64  #define DLINFO_ITEMS 12
65  
66  static abi_ulong target_create_elf_tables(abi_ulong p, int argc, int envc,
67                                            abi_ulong stringp,
68                                            struct elfhdr *exec,
69                                            abi_ulong load_addr,
70                                            abi_ulong load_bias,
71                                            abi_ulong interp_load_addr,
72                                            struct image_info *info)
73  {
74          abi_ulong sp;
75          int size;
76          abi_ulong u_platform;
77          const char *k_platform;
78          const int n = sizeof(elf_addr_t);
79  
80          sp = p;
81          u_platform = 0;
82          k_platform = ELF_PLATFORM;
83          if (k_platform) {
84              size_t len = strlen(k_platform) + 1;
85              sp -= (len + n - 1) & ~(n - 1);
86              u_platform = sp;
87              /* FIXME - check return value of memcpy_to_target() for failure */
88              memcpy_to_target(sp, k_platform, len);
89          }
90          /*
91           * Force 16 byte _final_ alignment here for generality.
92           */
93          sp = sp & ~(abi_ulong)15;
94          size = (DLINFO_ITEMS + 1) * 2;
95          if (k_platform) {
96              size += 2;
97          }
98  #ifdef DLINFO_ARCH_ITEMS
99          size += DLINFO_ARCH_ITEMS * 2;
100  #endif
101          size += envc + argc + 2;
102          size += 1;                         /* argc itself */
103          size *= n;
104          if (size & 15) {
105              sp -= 16 - (size & 15);
106          }
107  
108          /*
109           * NetBSD defines elf_addr_t as Elf32_Off / Elf64_Off
110           */
111  #define NEW_AUX_ENT(id, val) do {               \
112              sp -= n; put_user_ual(val, sp);     \
113              sp -= n; put_user_ual(id, sp);      \
114            } while (0)
115  
116          NEW_AUX_ENT(AT_NULL, 0);
117  
118          /* There must be exactly DLINFO_ITEMS entries here.  */
119          NEW_AUX_ENT(AT_PHDR, (abi_ulong)(load_addr + exec->e_phoff));
120          NEW_AUX_ENT(AT_PHENT, (abi_ulong)(sizeof(struct elf_phdr)));
121          NEW_AUX_ENT(AT_PHNUM, (abi_ulong)(exec->e_phnum));
122          NEW_AUX_ENT(AT_PAGESZ, (abi_ulong)(TARGET_PAGE_SIZE));
123          NEW_AUX_ENT(AT_BASE, (abi_ulong)(interp_load_addr));
124          NEW_AUX_ENT(AT_FLAGS, (abi_ulong)0);
125          NEW_AUX_ENT(AT_ENTRY, load_bias + exec->e_entry);
126          NEW_AUX_ENT(AT_UID, (abi_ulong)getuid());
127          NEW_AUX_ENT(AT_EUID, (abi_ulong)geteuid());
128          NEW_AUX_ENT(AT_GID, (abi_ulong)getgid());
129          NEW_AUX_ENT(AT_EGID, (abi_ulong)getegid());
130          NEW_AUX_ENT(AT_HWCAP, (abi_ulong)ELF_HWCAP);
131          NEW_AUX_ENT(AT_CLKTCK, (abi_ulong)sysconf(_SC_CLK_TCK));
132          if (k_platform) {
133              NEW_AUX_ENT(AT_PLATFORM, u_platform);
134          }
135  #ifdef ARCH_DLINFO
136          /*
137           * ARCH_DLINFO must come last so platform specific code can enforce
138           * special alignment requirements on the AUXV if necessary (eg. PPC).
139           */
140          ARCH_DLINFO;
141  #endif
142  #undef NEW_AUX_ENT
143  
144          sp = loader_build_argptr(envc, argc, sp, stringp);
145          return sp;
146  }
147  
148  #endif /* TARGET_OS_ELF_H */
149