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char *readsonameXX(char *name, FILE *infile, int expected_type, int *type)
{
ElfW(Ehdr) *epnt;
ElfW(Phdr) *ppnt;
unsigned int i, j;
char *header;
ElfW(Addr) dynamic_addr = 0;
ElfW(Addr) dynamic_size = 0;
unsigned long page_size = getpagesize();
ElfW(Addr) strtab_val = 0;
ElfW(Addr) needed_val;
ElfW(Addr) loadaddr = -1;
ElfW(Dyn) *dpnt;
struct stat st;
char *needed;
char *soname = NULL;
int multi_libcs = 0;
if (expected_type == LIB_DLL) {
warn("%s does not match type specified for directory!", name);
expected_type = LIB_ANY;
}
*type = LIB_ELF;
if (fstat(fileno(infile), &st))
return NULL;
header =
mmap(0, st.st_size, PROT_READ | PROT_WRITE, MAP_PRIVATE,
fileno(infile), 0);
if (header == (caddr_t) - 1)
return NULL;
epnt = (ElfW(Ehdr) *) header;
if ((char *)(epnt + 1) > (char *)(header + st.st_size))
goto skip;
#if __BYTE_ORDER == __LITTLE_ENDIAN
byteswap = (epnt->e_ident[5] == ELFDATA2MSB) ? 1 : 0;
#elif __BYTE_ORDER == __BIG_ENDIAN
byteswap = (epnt->e_ident[5] == ELFDATA2LSB) ? 1 : 0;
#else
#error Unknown host byte order!
#endif
/* Be very lazy, and only byteswap the stuff we use */
if (byteswap == 1) {
epnt->e_phoff = bswap_32(epnt->e_phoff);
epnt->e_phnum = bswap_16(epnt->e_phnum);
}
ppnt = (ElfW(Phdr) *) & header[epnt->e_phoff];
if ((char *)ppnt < (char *)header ||
(char *)(ppnt + epnt->e_phnum) > (char *)(header + st.st_size))
goto skip;
for (i = 0; i < epnt->e_phnum; i++) {
/* Be very lazy, and only byteswap the stuff we use */
if (byteswap == 1) {
ppnt->p_type = bswap_32(ppnt->p_type);
ppnt->p_vaddr = bswap_32(ppnt->p_vaddr);
ppnt->p_offset = bswap_32(ppnt->p_offset);
ppnt->p_filesz = bswap_32(ppnt->p_filesz);
}
if (loadaddr == (ElfW(Addr)) - 1 && ppnt->p_type == PT_LOAD)
loadaddr = (ppnt->p_vaddr & ~(page_size - 1)) -
(ppnt->p_offset & ~(page_size - 1));
if (ppnt->p_type == 2) {
dynamic_addr = ppnt->p_offset;
dynamic_size = ppnt->p_filesz;
};
ppnt++;
};
dpnt = (ElfW(Dyn) *) & header[dynamic_addr];
dynamic_size = dynamic_size / sizeof(ElfW(Dyn));
if ((char *)dpnt < (char *)header ||
(char *)(dpnt + dynamic_size) > (char *)(header + st.st_size))
goto skip;
if (byteswap == 1) {
dpnt->d_tag = bswap_32(dpnt->d_tag);
dpnt->d_un.d_val = bswap_32(dpnt->d_un.d_val);
}
while (dpnt->d_tag != DT_NULL) {
if (dpnt->d_tag == DT_STRTAB)
strtab_val = dpnt->d_un.d_val;
dpnt++;
if (byteswap == 1) {
dpnt->d_tag = bswap_32(dpnt->d_tag);
dpnt->d_un.d_val = bswap_32(dpnt->d_un.d_val);
}
};
if (!strtab_val)
goto skip;
dpnt = (ElfW(Dyn) *) & header[dynamic_addr];
while (dpnt->d_tag != DT_NULL) {
if (dpnt->d_tag == DT_SONAME || dpnt->d_tag == DT_NEEDED) {
needed_val = dpnt->d_un.d_val;
if (needed_val + strtab_val >= loadaddr ||
needed_val + strtab_val < st.st_size - loadaddr) {
needed =
(char *)(header - loadaddr + strtab_val +
needed_val);
if (dpnt->d_tag == DT_SONAME)
soname = xstrdup(needed);
for (j = 0; needed_tab[j].soname != NULL; j++) {
if (strcmp(needed, needed_tab[j].soname)
== 0) {
if (*type != LIB_ELF
&& *type !=
needed_tab[j].type)
multi_libcs = 1;
*type = needed_tab[j].type;
}
}
}
}
dpnt++;
};
if (multi_libcs)
warn("%s appears to be for multiple libc's", name);
/* If we could not deduce the libc type, and we know what to expect, set the type */
if (*type == LIB_ELF && expected_type != LIB_ANY)
*type = expected_type;
if (expected_type != LIB_ANY && expected_type != LIB_ELF &&
expected_type != *type) {
warn("%s does not match type specified for directory!", name);
}
skip:
munmap(header, st.st_size);
return soname;
}
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