1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Program to hack in a PT_NOTE program header entry in an ELF file. |
4 | * This is needed for OF on RS/6000s to load an image correctly. |
5 | * Note that OF needs a program header entry for the note, not an |
6 | * ELF section. |
7 | * |
8 | * Copyright 2000 Paul Mackerras. |
9 | * |
10 | * Adapted for 64 bit little endian images by Andrew Tauferner. |
11 | * |
12 | * Usage: addnote zImage |
13 | */ |
14 | #include <stdio.h> |
15 | #include <stdlib.h> |
16 | #include <fcntl.h> |
17 | #include <unistd.h> |
18 | #include <string.h> |
19 | |
20 | /* CHRP note section */ |
21 | static const char arch[] = "PowerPC" ; |
22 | |
23 | #define N_DESCR 6 |
24 | unsigned int descr[N_DESCR] = { |
25 | 0xffffffff, /* real-mode = true */ |
26 | 0x02000000, /* real-base, i.e. where we expect OF to be */ |
27 | 0xffffffff, /* real-size */ |
28 | 0xffffffff, /* virt-base */ |
29 | 0xffffffff, /* virt-size */ |
30 | 0x4000, /* load-base */ |
31 | }; |
32 | |
33 | /* RPA note section */ |
34 | static const char rpaname[] = "IBM,RPA-Client-Config" ; |
35 | |
36 | /* |
37 | * Note: setting ignore_my_client_config *should* mean that OF ignores |
38 | * all the other fields, but there is a firmware bug which means that |
39 | * it looks at the splpar field at least. So these values need to be |
40 | * reasonable. |
41 | */ |
42 | #define N_RPA_DESCR 8 |
43 | unsigned int rpanote[N_RPA_DESCR] = { |
44 | 0, /* lparaffinity */ |
45 | 64, /* min_rmo_size */ |
46 | 0, /* min_rmo_percent */ |
47 | 40, /* max_pft_size */ |
48 | 1, /* splpar */ |
49 | -1, /* min_load */ |
50 | 0, /* new_mem_def */ |
51 | 1, /* ignore_my_client_config */ |
52 | }; |
53 | |
54 | #define ROUNDUP(len) (((len) + 3) & ~3) |
55 | |
56 | unsigned char buf[1024]; |
57 | #define ELFDATA2LSB 1 |
58 | #define ELFDATA2MSB 2 |
59 | static int e_data = ELFDATA2MSB; |
60 | #define ELFCLASS32 1 |
61 | #define ELFCLASS64 2 |
62 | static int e_class = ELFCLASS32; |
63 | |
64 | #define GET_16BE(off) ((buf[off] << 8) + (buf[(off)+1])) |
65 | #define GET_32BE(off) ((GET_16BE(off) << 16U) + GET_16BE((off)+2U)) |
66 | #define GET_64BE(off) ((((unsigned long long)GET_32BE(off)) << 32ULL) + \ |
67 | ((unsigned long long)GET_32BE((off)+4ULL))) |
68 | #define PUT_16BE(off, v)(buf[off] = ((v) >> 8) & 0xff, \ |
69 | buf[(off) + 1] = (v) & 0xff) |
70 | #define PUT_32BE(off, v)(PUT_16BE((off), (v) >> 16L), PUT_16BE((off) + 2, (v))) |
71 | #define PUT_64BE(off, v)((PUT_32BE((off), (v) >> 32L), \ |
72 | PUT_32BE((off) + 4, (v)))) |
73 | |
74 | #define GET_16LE(off) ((buf[off]) + (buf[(off)+1] << 8)) |
75 | #define GET_32LE(off) (GET_16LE(off) + (GET_16LE((off)+2U) << 16U)) |
76 | #define GET_64LE(off) ((unsigned long long)GET_32LE(off) + \ |
77 | (((unsigned long long)GET_32LE((off)+4ULL)) << 32ULL)) |
78 | #define PUT_16LE(off, v) (buf[off] = (v) & 0xff, \ |
79 | buf[(off) + 1] = ((v) >> 8) & 0xff) |
80 | #define PUT_32LE(off, v) (PUT_16LE((off), (v)), PUT_16LE((off) + 2, (v) >> 16L)) |
81 | #define PUT_64LE(off, v) (PUT_32LE((off), (v)), PUT_32LE((off) + 4, (v) >> 32L)) |
82 | |
83 | #define GET_16(off) (e_data == ELFDATA2MSB ? GET_16BE(off) : GET_16LE(off)) |
84 | #define GET_32(off) (e_data == ELFDATA2MSB ? GET_32BE(off) : GET_32LE(off)) |
85 | #define GET_64(off) (e_data == ELFDATA2MSB ? GET_64BE(off) : GET_64LE(off)) |
86 | #define PUT_16(off, v) (e_data == ELFDATA2MSB ? PUT_16BE(off, v) : \ |
87 | PUT_16LE(off, v)) |
88 | #define PUT_32(off, v) (e_data == ELFDATA2MSB ? PUT_32BE(off, v) : \ |
89 | PUT_32LE(off, v)) |
90 | #define PUT_64(off, v) (e_data == ELFDATA2MSB ? PUT_64BE(off, v) : \ |
91 | PUT_64LE(off, v)) |
92 | |
93 | /* Structure of an ELF file */ |
94 | #define E_IDENT 0 /* ELF header */ |
95 | #define E_PHOFF (e_class == ELFCLASS32 ? 28 : 32) |
96 | #define E_PHENTSIZE (e_class == ELFCLASS32 ? 42 : 54) |
97 | #define E_PHNUM (e_class == ELFCLASS32 ? 44 : 56) |
98 | #define E_HSIZE (e_class == ELFCLASS32 ? 52 : 64) |
99 | |
100 | #define EI_MAGIC 0 /* offsets in E_IDENT area */ |
101 | #define EI_CLASS 4 |
102 | #define EI_DATA 5 |
103 | |
104 | #define PH_TYPE 0 /* ELF program header */ |
105 | #define PH_OFFSET (e_class == ELFCLASS32 ? 4 : 8) |
106 | #define PH_FILESZ (e_class == ELFCLASS32 ? 16 : 32) |
107 | #define PH_HSIZE (e_class == ELFCLASS32 ? 32 : 56) |
108 | |
109 | #define PT_NOTE 4 /* Program header type = note */ |
110 | |
111 | |
112 | unsigned char elf_magic[4] = { 0x7f, 'E', 'L', 'F' }; |
113 | |
114 | int |
115 | main(int ac, char **av) |
116 | { |
117 | int fd, n, i; |
118 | unsigned long ph, ps, np; |
119 | long nnote, nnote2, ns; |
120 | |
121 | if (ac != 2) { |
122 | fprintf(stderr, "Usage: %s elf-file\n" , av[0]); |
123 | exit(1); |
124 | } |
125 | fd = open(av[1], O_RDWR); |
126 | if (fd < 0) { |
127 | perror(av[1]); |
128 | exit(1); |
129 | } |
130 | |
131 | nnote = 12 + ROUNDUP(strlen(arch) + 1) + sizeof(descr); |
132 | nnote2 = 12 + ROUNDUP(strlen(rpaname) + 1) + sizeof(rpanote); |
133 | |
134 | n = read(fd, buf, sizeof(buf)); |
135 | if (n < 0) { |
136 | perror("read" ); |
137 | exit(1); |
138 | } |
139 | |
140 | if (memcmp(&buf[E_IDENT+EI_MAGIC], elf_magic, 4) != 0) |
141 | goto notelf; |
142 | e_class = buf[E_IDENT+EI_CLASS]; |
143 | if (e_class != ELFCLASS32 && e_class != ELFCLASS64) |
144 | goto notelf; |
145 | e_data = buf[E_IDENT+EI_DATA]; |
146 | if (e_data != ELFDATA2MSB && e_data != ELFDATA2LSB) |
147 | goto notelf; |
148 | if (n < E_HSIZE) |
149 | goto notelf; |
150 | |
151 | ph = (e_class == ELFCLASS32 ? GET_32(E_PHOFF) : GET_64(E_PHOFF)); |
152 | ps = GET_16(E_PHENTSIZE); |
153 | np = GET_16(E_PHNUM); |
154 | if (ph < E_HSIZE || ps < PH_HSIZE || np < 1) |
155 | goto notelf; |
156 | if (ph + (np + 2) * ps + nnote + nnote2 > n) |
157 | goto nospace; |
158 | |
159 | for (i = 0; i < np; ++i) { |
160 | if (GET_32(ph + PH_TYPE) == PT_NOTE) { |
161 | fprintf(stderr, "%s already has a note entry\n" , |
162 | av[1]); |
163 | exit(0); |
164 | } |
165 | ph += ps; |
166 | } |
167 | |
168 | /* XXX check that the area we want to use is all zeroes */ |
169 | for (i = 0; i < 2 * ps + nnote + nnote2; ++i) |
170 | if (buf[ph + i] != 0) |
171 | goto nospace; |
172 | |
173 | /* fill in the program header entry */ |
174 | ns = ph + 2 * ps; |
175 | PUT_32(ph + PH_TYPE, PT_NOTE); |
176 | if (e_class == ELFCLASS32) |
177 | PUT_32(ph + PH_OFFSET, ns); |
178 | else |
179 | PUT_64(ph + PH_OFFSET, ns); |
180 | |
181 | if (e_class == ELFCLASS32) |
182 | PUT_32(ph + PH_FILESZ, nnote); |
183 | else |
184 | PUT_64(ph + PH_FILESZ, nnote); |
185 | |
186 | /* fill in the note area we point to */ |
187 | /* XXX we should probably make this a proper section */ |
188 | PUT_32(ns, strlen(arch) + 1); |
189 | PUT_32(ns + 4, N_DESCR * 4); |
190 | PUT_32(ns + 8, 0x1275); |
191 | strcpy(dest: (char *) &buf[ns + 12], src: arch); |
192 | ns += 12 + strlen(arch) + 1; |
193 | for (i = 0; i < N_DESCR; ++i, ns += 4) |
194 | PUT_32BE(ns, descr[i]); |
195 | |
196 | /* fill in the second program header entry and the RPA note area */ |
197 | ph += ps; |
198 | PUT_32(ph + PH_TYPE, PT_NOTE); |
199 | if (e_class == ELFCLASS32) |
200 | PUT_32(ph + PH_OFFSET, ns); |
201 | else |
202 | PUT_64(ph + PH_OFFSET, ns); |
203 | |
204 | if (e_class == ELFCLASS32) |
205 | PUT_32(ph + PH_FILESZ, nnote); |
206 | else |
207 | PUT_64(ph + PH_FILESZ, nnote2); |
208 | |
209 | /* fill in the note area we point to */ |
210 | PUT_32(ns, strlen(rpaname) + 1); |
211 | PUT_32(ns + 4, sizeof(rpanote)); |
212 | PUT_32(ns + 8, 0x12759999); |
213 | strcpy(dest: (char *) &buf[ns + 12], src: rpaname); |
214 | ns += 12 + ROUNDUP(strlen(rpaname) + 1); |
215 | for (i = 0; i < N_RPA_DESCR; ++i, ns += 4) |
216 | PUT_32BE(ns, rpanote[i]); |
217 | |
218 | /* Update the number of program headers */ |
219 | PUT_16(E_PHNUM, np + 2); |
220 | |
221 | /* write back */ |
222 | i = lseek(fd, (long) 0, SEEK_SET); |
223 | if (i < 0) { |
224 | perror("lseek" ); |
225 | exit(1); |
226 | } |
227 | i = write(fd, buf, n); |
228 | if (i < 0) { |
229 | perror("write" ); |
230 | exit(1); |
231 | } |
232 | if (i < n) { |
233 | fprintf(stderr, "%s: write truncated\n" , av[1]); |
234 | exit(1); |
235 | } |
236 | |
237 | exit(0); |
238 | |
239 | notelf: |
240 | fprintf(stderr, "%s does not appear to be an ELF file\n" , av[1]); |
241 | exit(1); |
242 | |
243 | nospace: |
244 | fprintf(stderr, "sorry, I can't find space in %s to put the note\n" , |
245 | av[1]); |
246 | exit(1); |
247 | } |
248 | |