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-rw-r--r--src/patchelf.cc127
1 files changed, 69 insertions, 58 deletions
diff --git a/src/patchelf.cc b/src/patchelf.cc
index 06cd1e3..ac83859 100644
--- a/src/patchelf.cc
+++ b/src/patchelf.cc
@@ -148,9 +148,9 @@ public:
string getInterpreter();
- string getSoname();
+ typedef enum { printSoname, replaceSoname } sonameMode;
- void setSoname(const string & newSoname);
+ void modifySoname(sonameMode op, const string & newSoname);
void setInterpreter(const string & newInterpreter);
@@ -882,8 +882,13 @@ string ElfFile<ElfFileParamNames>::getInterpreter()
}
template<ElfFileParams>
-string ElfFile<ElfFileParamNames>::getSoname()
+void ElfFile<ElfFileParamNames>::modifySoname(sonameMode op, const string & newSoname)
{
+ if (rdi(hdr->e_type) != ET_DYN) {
+ debug("this is not a dynamic library\n");
+ return;
+ }
+
Elf_Shdr & shdrDynamic = findSection(".dynamic");
Elf_Shdr & shdrDynStr = findSection(".dynstr");
char * strTab = (char *) contents + rdi(shdrDynStr.sh_offset);
@@ -892,76 +897,82 @@ string ElfFile<ElfFileParamNames>::getSoname()
Elf_Dyn * dyn = (Elf_Dyn *) (contents + rdi(shdrDynamic.sh_offset));
Elf_Addr strTabAddr = 0;
for ( ; rdi(dyn->d_tag) != DT_NULL; dyn++)
- if (rdi(dyn->d_tag) == DT_STRTAB) strTabAddr = rdi(dyn->d_un.d_ptr);
+ if (rdi(dyn->d_tag) == DT_STRTAB)
+ strTabAddr = rdi(dyn->d_un.d_ptr);
if (!strTabAddr) error("strange: no string table");
/* We assume that the virtual address in the DT_STRTAB entry
of the dynamic section corresponds to the .dynstr section. */
assert(strTabAddr == rdi(shdrDynStr.sh_addr));
- Elf_Dyn * dynSoname = (Elf_Dyn *) (contents + rdi(shdrDynamic.sh_offset));
+ /* Walk through the dynamic section, look for the DT_SONAME entry. */
+ static vector<string> neededLibs;
+ dyn = (Elf_Dyn *) (contents + rdi(shdrDynamic.sh_offset));
+ Elf_Dyn * dynSoname = 0;
char * soname = 0;
- for ( ; rdi(dynSoname->d_tag) != DT_NULL; dynSoname++) {
- if (rdi(dynSoname->d_tag) == DT_SONAME) {
- soname = strTab + rdi(dynSoname->d_un.d_val);
- break;
+ for ( ; rdi(dyn->d_tag) != DT_NULL; dyn++) {
+ if (rdi(dyn->d_tag) == DT_SONAME) {
+ dynSoname = dyn;
+ soname = strTab + rdi(dyn->d_un.d_val);
+ } else if (rdi(dyn->d_tag) == DT_INIT)
+ neededLibs.push_back(string(strTab + rdi(dyn->d_un.d_val)));
+ }
+
+ if (op == printSoname) {
+ if (soname) {
+ if (string(soname ? soname : "") == "")
+ debug("DT_SONAME is empty\n");
+ else
+ printf("%s\n", soname);
+ } else {
+ debug("no DT_SONAME found\n");
}
+ return;
}
- if (rdi(dynSoname->d_tag) == DT_NULL)
- error("Specified ELF file does not contain any DT_SONAME entry in .dynamic section!");
+ if (string(soname ? soname : "") == newSoname) {
+ debug("current and proposed new SONAMEs are equal keeping DT_SONAME entry\n");
+ return;
+ }
- return soname;
-}
+ /* Zero out the previous SONAME */
+ unsigned int sonameSize = 0;
+ if (soname) {
+ sonameSize = strlen(soname);
+ memset(soname, 'X', sonameSize);
+ }
-template<ElfFileParams>
-void ElfFile<ElfFileParamNames>::setSoname(const string & newSoname)
-{
- Elf_Shdr & shdrDynamic = findSection(".dynamic");
- Elf_Shdr & shdrDynStr = findSection(".dynstr");
- char * strTab = (char *) contents + rdi(shdrDynStr.sh_offset);
+ debug("new SONAME is `%s'\n", newSoname.c_str());
- /* Find the DT_STRTAB entry in the dynamic section. */
- Elf_Dyn * dyn = (Elf_Dyn *) (contents + rdi(shdrDynamic.sh_offset));
- Elf_Addr strTabAddr = 0;
- for ( ; rdi(dyn->d_tag) != DT_NULL; dyn++)
- if (rdi(dyn->d_tag) == DT_STRTAB) strTabAddr = rdi(dyn->d_un.d_ptr);
- if (!strTabAddr) error("strange: no string table");
+ /* Grow the .dynstr section to make room for the new SONAME. */
+ debug("SONAME is too long, resizing...\n");
- /* We assume that the virtual address in the DT_STRTAB entry
- of the dynamic section corresponds to the .dynstr section. */
- assert(strTabAddr == rdi(shdrDynStr.sh_addr));
+ string & newDynStr = replaceSection(".dynstr", rdi(shdrDynStr.sh_size) + newSoname.size() + 1);
+ setSubstr(newDynStr, rdi(shdrDynStr.sh_size), newSoname + '\0');
- Elf_Dyn * dynSoname = (Elf_Dyn *) (contents + rdi(shdrDynamic.sh_offset));
- char * soname = 0;
- for ( ; rdi(dynSoname->d_tag) != DT_NULL; dynSoname++) {
- if (rdi(dynSoname->d_tag) == DT_SONAME) {
- soname = strTab + rdi(dynSoname->d_un.d_val);
- break;
- }
- }
- if (rdi(dynSoname->d_tag) == DT_NULL)
- error("Specified ELF file does not contain any DT_SONAME entry in .dynamic section!");
+ /* Update the DT_SONAME entry. */
+ if (dynSoname) {
+ dynSoname->d_un.d_val = shdrDynStr.sh_size;
+ } else {
+ /* There is no DT_SONAME entry in the .dynamic section, so we
+ have to grow the .dynamic section. */
+ string & newDynamic = replaceSection(".dynamic", rdi(shdrDynamic.sh_size) + sizeof(Elf_Dyn));
- if (newSoname.size() <= strlen(soname)) {
- debug("old soname: `%s', new soname: `%s'\n", soname, newSoname.c_str());
- strcpy(soname, newSoname.c_str());
- changed = true;
- }
- else {
- /* Grow the .dynstr section to make room for the new DT_SONAME */
- debug("new soname is too long, resizing .dynstr section...\n");
-
- string & newDynStr = replaceSection(".dynstr",
- rdi(shdrDynStr.sh_size) + newSoname.size() + 1);
- setSubstr(newDynStr, rdi(shdrDynStr.sh_size), newSoname + '\0');
- /* Update the DT_SONAME entry, if any */
- if (dynSoname) {
- debug("old soname: `%s', new soname: `%s'\n", soname, newSoname.c_str());
- dynSoname->d_un.d_val = shdrDynStr.sh_size;
- changed = true;
- }
+ unsigned int idx = 0;
+ for (; rdi(((Elf_Dyn *) newDynamic.c_str())[idx].d_tag) != DT_NULL; idx++);
+ debug("DT_NULL index is %d\n", idx);
+
+ /* Shift all entries down by one. */
+ setSubstr(newDynamic, sizeof(Elf_Dyn), string(newDynamic, 0, sizeof(Elf_Dyn) * (idx + 1)));
+
+ /* Add the DT_SONAME entry at the top. */
+ Elf_Dyn newDyn;
+ wri(newDyn.d_tag, DT_SONAME);
+ newDyn.d_un.d_val = shdrDynStr.sh_size;
+ setSubstr(newDynamic, 0, string((char *)&newDyn, sizeof(Elf_Dyn)));
}
+
+ changed = true;
}
template<ElfFileParams>
@@ -1334,10 +1345,10 @@ static void patchElf2(ElfFile & elfFile, mode_t fileMode)
printf("%s\n", elfFile.getInterpreter().c_str());
if (printSoname)
- printf("%s\n", elfFile.getSoname().c_str());
+ elfFile.modifySoname(elfFile.printSoname, "");
if (setSoname)
- elfFile.setSoname(newSoname);
+ elfFile.modifySoname(elfFile.replaceSoname, newSoname);
if (newInterpreter != "")
elfFile.setInterpreter(newInterpreter);
generated by cgit v0.12 at 2024-10-31 11:46:12 (GMT)