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/* a.out */
struct exec {
unsigned long a_midmag; /* flags<<26 | mid<<16 | magic */
unsigned long a_text; /* text segment size */
unsigned long a_data; /* initialized data size */
unsigned long a_bss; /* uninitialized data size */
unsigned long a_syms; /* symbol table size */
unsigned long a_entry; /* entry point */
unsigned long a_trsize; /* text relocation size */
unsigned long a_drsize; /* data relocation size */
};
struct aout_state {
struct exec head;
unsigned long curaddr;
int segment; /* current segment number, -1 for none */
unsigned long loc; /* start offset of current block */
unsigned long skip; /* padding to be skipped to current segment */
unsigned long toread; /* remaining data to be read in the segment */
};
static struct aout_state astate;
static sector_t aout_download(unsigned char *data, unsigned int len, int eof);
static inline os_download_t aout_probe(unsigned char *data, unsigned int len)
{
unsigned long start, mid, end, istart, iend;
if (len < sizeof(astate.head)) {
return 0;
}
memcpy(&astate.head, data, sizeof(astate.head));
if ((astate.head.a_midmag & 0xffff) != 0x010BL) {
return 0;
}
printf("(a.out");
aout_freebsd_probe();
printf(")... ");
/* Check the aout image */
start = astate.head.a_entry;
mid = (((start + astate.head.a_text) + 4095) & ~4095) + astate.head.a_data;
end = ((mid + 4095) & ~4095) + astate.head.a_bss;
istart = 4096;
iend = istart + (mid - start);
if (!prep_segment(start, mid, end, istart, iend))
return dead_download;
astate.segment = -1;
astate.loc = 0;
astate.skip = 0;
astate.toread = 0;
return aout_download;
}
static sector_t aout_download(unsigned char *data, unsigned int len, int eof)
{
unsigned int offset; /* working offset in the current data block */
offset = 0;
#ifdef AOUT_LYNX_KDI
astate.segment++;
if (astate.segment == 0) {
astate.curaddr = 0x100000;
astate.head.a_entry = astate.curaddr + 0x20;
}
memcpy(phys_to_virt(astate.curaddr), data, len);
astate.curaddr += len;
return 0;
#endif
do {
if (astate.segment != -1) {
if (astate.skip) {
if (astate.skip >= len - offset) {
astate.skip -= len - offset;
break;
}
offset += astate.skip;
astate.skip = 0;
}
if (astate.toread) {
if (astate.toread >= len - offset) {
memcpy(phys_to_virt(astate.curaddr), data+offset,
len - offset);
astate.curaddr += len - offset;
astate.toread -= len - offset;
break;
}
memcpy(phys_to_virt(astate.curaddr), data+offset, astate.toread);
offset += astate.toread;
astate.toread = 0;
}
}
/* Data left, but current segment finished - look for the next
* segment. This is quite simple for a.out files. */
astate.segment++;
switch (astate.segment) {
case 0:
/* read text */
astate.curaddr = astate.head.a_entry;
astate.skip = 4096;
astate.toread = astate.head.a_text;
break;
case 1:
/* read data */
/* skip and curaddr may be wrong, but I couldn't find
* examples where this failed. There is no reasonable
* documentation for a.out available. */
astate.skip = ((astate.curaddr + 4095) & ~4095) - astate.curaddr;
astate.curaddr = (astate.curaddr + 4095) & ~4095;
astate.toread = astate.head.a_data;
break;
case 2:
/* initialize bss and start kernel */
astate.curaddr = (astate.curaddr + 4095) & ~4095;
astate.skip = 0;
astate.toread = 0;
memset(phys_to_virt(astate.curaddr), '\0', astate.head.a_bss);
goto aout_startkernel;
default:
break;
}
} while (offset < len);
astate.loc += len;
if (eof) {
unsigned long entry;
aout_startkernel:
entry = astate.head.a_entry;
done(1);
aout_freebsd_boot();
#ifdef AOUT_LYNX_KDI
xstart32(entry);
#endif
printf("unexpected a.out variant\n");
longjmp(restart_etherboot, -2);
}
return 0;
}
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