// SPDX-License-Identifier: GPL-2.0-or-later/* * Program to hack in a PT_NOTE program header entry in an ELF file. * This is needed for OF on RS/6000s to load an image correctly. * Note that OF needs a program header entry for the note, not an * ELF section. * * Copyright 2000 Paul Mackerras. * * Adapted for 64 bit little endian images by Andrew Tauferner. * * Usage: addnote zImage */#include <stdio.h>#include <stdlib.h>#include <fcntl.h>#include <unistd.h>#include <string.h> /* CHRP note section */static const char arch[] = "PowerPC"; #define N_DESCR	6unsigned int descr[N_DESCR] = {	0xffffffff,		/* real-mode = true */	0x02000000,		/* real-base, i.e. where we expect OF to be */	0xffffffff,		/* real-size */	0xffffffff,		/* virt-base */	0xffffffff,		/* virt-size */	0x4000,			/* load-base */}; /* RPA note section */static const char rpaname[] = "IBM,RPA-Client-Config"; /* * Note: setting ignore_my_client_config *should* mean that OF ignores * all the other fields, but there is a firmware bug which means that * it looks at the splpar field at least.  So these values need to be * reasonable. */#define N_RPA_DESCR	8unsigned int rpanote[N_RPA_DESCR] = {	0,			/* lparaffinity */	64,			/* min_rmo_size */	0,			/* min_rmo_percent */	40,			/* max_pft_size */	1,			/* splpar */	-1,			/* min_load */	0,			/* new_mem_def */	1,			/* ignore_my_client_config */}; #define ROUNDUP(len)	(((len) + 3) & ~3) unsigned char buf[1024];#define ELFDATA2LSB     1#define ELFDATA2MSB     2static int e_data = ELFDATA2MSB;#define ELFCLASS32      1#define ELFCLASS64      2static int e_class = ELFCLASS32; #define GET_16BE(off)	((buf[off] << 8) + (buf[(off)+1]))#define GET_32BE(off)	((GET_16BE(off) << 16U) + GET_16BE((off)+2U))#define GET_64BE(off)	((((unsigned long long)GET_32BE(off)) << 32ULL) + \			((unsigned long long)GET_32BE((off)+4ULL)))#define PUT_16BE(off, v)(buf[off] = ((v) >> 8) & 0xff, \			 buf[(off) + 1] = (v) & 0xff)#define PUT_32BE(off, v)(PUT_16BE((off), (v) >> 16L), PUT_16BE((off) + 2, (v)))#define PUT_64BE(off, v)((PUT_32BE((off), (unsigned long long)(v) >> 32L), \			  PUT_32BE((off) + 4, (unsigned long long)(v)))) #define GET_16LE(off)	((buf[off]) + (buf[(off)+1] << 8))#define GET_32LE(off)	(GET_16LE(off) + (GET_16LE((off)+2U) << 16U))#define GET_64LE(off)	((unsigned long long)GET_32LE(off) + \			(((unsigned long long)GET_32LE((off)+4ULL)) << 32ULL))#define PUT_16LE(off, v) (buf[off] = (v) & 0xff, \			  buf[(off) + 1] = ((v) >> 8) & 0xff)#define PUT_32LE(off, v) (PUT_16LE((off), (v)), PUT_16LE((off) + 2, (v) >> 16L))#define PUT_64LE(off, v) (PUT_32LE((off), (unsigned long long)(v)), \			  PUT_32LE((off) + 4, (unsigned long long)(v) >> 32L)) #define GET_16(off)	(e_data == ELFDATA2MSB ? GET_16BE(off) : GET_16LE(off))#define GET_32(off)	(e_data == ELFDATA2MSB ? GET_32BE(off) : GET_32LE(off))#define GET_64(off)	(e_data == ELFDATA2MSB ? GET_64BE(off) : GET_64LE(off))#define PUT_16(off, v)	(e_data == ELFDATA2MSB ? PUT_16BE(off, v) : \			 PUT_16LE(off, v))#define PUT_32(off, v)  (e_data == ELFDATA2MSB ? PUT_32BE(off, v) : \			 PUT_32LE(off, v))#define PUT_64(off, v)  (e_data == ELFDATA2MSB ? PUT_64BE(off, v) : \			 PUT_64LE(off, v)) /* Structure of an ELF file */#define E_IDENT		0	/* ELF header */#define	E_PHOFF		(e_class == ELFCLASS32 ? 28 : 32)#define E_PHENTSIZE	(e_class == ELFCLASS32 ? 42 : 54)#define E_PHNUM		(e_class == ELFCLASS32 ? 44 : 56)#define E_HSIZE		(e_class == ELFCLASS32 ? 52 : 64) #define EI_MAGIC	0	/* offsets in E_IDENT area */#define EI_CLASS	4#define EI_DATA		5 #define PH_TYPE		0	/* ELF program header */#define PH_OFFSET	(e_class == ELFCLASS32 ? 4 : 8)#define PH_FILESZ	(e_class == ELFCLASS32 ? 16 : 32)#define PH_HSIZE	(e_class == ELFCLASS32 ? 32 : 56) #define PT_NOTE		4	/* Program header type = note */  unsigned char elf_magic[4] = { 0x7f, 'E', 'L', 'F' }; intmain(int ac, char **av){	int fd, n, i;	unsigned long ph, ps, np;	long nnote, nnote2, ns; 	if (ac != 2) {		fprintf(stderr, "Usage: %s elf-file\n", av[0]);		exit(1);	}	fd = open(av[1], O_RDWR);	if (fd < 0) {		perror(av[1]);		exit(1);	} 	nnote = 12 + ROUNDUP(strlen(arch) + 1) + sizeof(descr);	nnote2 = 12 + ROUNDUP(strlen(rpaname) + 1) + sizeof(rpanote); 	n = read(fd, buf, sizeof(buf));	if (n < 0) {		perror("read");		exit(1);	} 	if (memcmp(&buf[E_IDENT+EI_MAGIC], elf_magic, 4) != 0)		goto notelf;	e_class = buf[E_IDENT+EI_CLASS];	if (e_class != ELFCLASS32 && e_class != ELFCLASS64)		goto notelf;	e_data = buf[E_IDENT+EI_DATA];	if (e_data != ELFDATA2MSB && e_data != ELFDATA2LSB)		goto notelf;	if (n < E_HSIZE)		goto notelf; 	ph = (e_class == ELFCLASS32 ? GET_32(E_PHOFF) : GET_64(E_PHOFF));	ps = GET_16(E_PHENTSIZE);	np = GET_16(E_PHNUM);	if (ph < E_HSIZE || ps < PH_HSIZE || np < 1)		goto notelf;	if (ph + (np + 2) * ps + nnote + nnote2 > n)		goto nospace; 	for (i = 0; i < np; ++i) {		if (GET_32(ph + PH_TYPE) == PT_NOTE) {			fprintf(stderr, "%s already has a note entry\n",				av[1]);			exit(0);		}		ph += ps;	} 	/* XXX check that the area we want to use is all zeroes */	for (i = 0; i < 2 * ps + nnote + nnote2; ++i)		if (buf[ph + i] != 0)			goto nospace; 	/* fill in the program header entry */	ns = ph + 2 * ps;	PUT_32(ph + PH_TYPE, PT_NOTE);	if (e_class == ELFCLASS32)		PUT_32(ph + PH_OFFSET, ns);	else		PUT_64(ph + PH_OFFSET, ns); 	if (e_class == ELFCLASS32)		PUT_32(ph + PH_FILESZ, nnote);	else		PUT_64(ph + PH_FILESZ, nnote); 	/* fill in the note area we point to */	/* XXX we should probably make this a proper section */	PUT_32(ns, strlen(arch) + 1);	PUT_32(ns + 4, N_DESCR * 4);	PUT_32(ns + 8, 0x1275);	strcpy((char *) &buf[ns + 12], arch);	ns += 12 + strlen(arch) + 1;	for (i = 0; i < N_DESCR; ++i, ns += 4)		PUT_32BE(ns, descr[i]); 	/* fill in the second program header entry and the RPA note area */	ph += ps;	PUT_32(ph + PH_TYPE, PT_NOTE);	if (e_class == ELFCLASS32)		PUT_32(ph + PH_OFFSET, ns);	else		PUT_64(ph + PH_OFFSET, ns); 	if (e_class == ELFCLASS32)		PUT_32(ph + PH_FILESZ, nnote);	else		PUT_64(ph + PH_FILESZ, nnote2); 	/* fill in the note area we point to */	PUT_32(ns, strlen(rpaname) + 1);	PUT_32(ns + 4, sizeof(rpanote));	PUT_32(ns + 8, 0x12759999);	strcpy((char *) &buf[ns + 12], rpaname);	ns += 12 + ROUNDUP(strlen(rpaname) + 1);	for (i = 0; i < N_RPA_DESCR; ++i, ns += 4)		PUT_32BE(ns, rpanote[i]); 	/* Update the number of program headers */	PUT_16(E_PHNUM, np + 2); 	/* write back */	i = lseek(fd, (long) 0, SEEK_SET);	if (i < 0) {		perror("lseek");		exit(1);	}	i = write(fd, buf, n);	if (i < 0) {		perror("write");		exit(1);	}	if (i < n) {		fprintf(stderr, "%s: write truncated\n", av[1]);		exit(1);	} 	exit(0);  notelf:	fprintf(stderr, "%s does not appear to be an ELF file\n", av[1]);	exit(1);  nospace:	fprintf(stderr, "sorry, I can't find space in %s to put the note\n",		av[1]);	exit(1);}