5 #include <libelf/libelf.h>
6 #include <libelf/gelf.h>
7 #include <libelfu/libelfu.h>
10 static int cmpScnOffs(const void *ms1, const void *ms2)
15 ElfuScn *s1 = *(ElfuScn**)ms1;
16 ElfuScn *s2 = *(ElfuScn**)ms2;
22 if (s1->shdr.sh_offset < s2->shdr.sh_offset) {
24 } else if (s1->shdr.sh_offset == s2->shdr.sh_offset) {
26 } else /* if (s1->shdr.sh_offset > s2->shdr.sh_offset) */ {
33 static ElfuPhdr* parentPhdr(ElfuElf *me, ElfuScn *ms)
40 CIRCLEQ_FOREACH(mp, &me->phdrList, elem) {
41 if (ms->shdr.sh_addr >= mp->phdr.p_vaddr
42 && OFFS_END(ms->shdr.sh_addr, ms->shdr.sh_size) <= OFFS_END(mp->phdr.p_vaddr, mp->phdr.p_memsz)) {
44 } else if (ms->shdr.sh_offset >= mp->phdr.p_offset
45 && OFFS_END(ms->shdr.sh_offset, SCNFILESIZE(&ms->shdr)) <= OFFS_END(mp->phdr.p_offset, mp->phdr.p_filesz)
46 && OFFS_END(ms->shdr.sh_offset, ms->shdr.sh_size) <= OFFS_END(mp->phdr.p_offset, mp->phdr.p_memsz)) {
55 static ElfuPhdr* modelFromPhdr(GElf_Phdr *phdr)
61 mp = malloc(sizeof(ElfuPhdr));
63 ELFU_WARN("modelFromPhdr: malloc() failed for ElfuPhdr.\n");
69 CIRCLEQ_INIT(&mp->phdrToScnList);
75 static ElfuScn* modelFromSection(Elf_Scn *scn)
81 ms = malloc(sizeof(ElfuScn));
83 ELFU_WARN("modelFromSection: malloc() failed for ElfuScn.\n");
88 assert(gelf_getshdr(scn, &ms->shdr) == &ms->shdr);
91 /* Copy each data part in source segment */
93 ms->data.d_buf = NULL;
95 ms->data.d_type = ELF_T_BYTE;
96 ms->data.d_size = ms->shdr.sh_size;
97 ms->data.d_version = elf_version(EV_NONE);
98 if (ms->shdr.sh_type != SHT_NOBITS
99 && ms->shdr.sh_size > 0) {
102 ms->data.d_buf = malloc(ms->shdr.sh_size);
103 if (!ms->data.d_buf) {
104 ELFU_WARN("modelFromSection: malloc() failed for data buffer (%jx bytes).\n", ms->shdr.sh_size);
108 /* A non-empty section should contain at least one data block. */
109 data = elf_rawdata(scn, NULL);
112 ms->data.d_align = data->d_align;
113 ms->data.d_type = data->d_type;
114 ms->data.d_version = data->d_version;
117 if (data->d_off + data->d_size > ms->shdr.sh_size) {
118 ELFU_WARN("modelFromSection: libelf delivered a bogus data blob. Skipping\n");
120 memcpy(ms->data.d_buf + data->d_off, data->d_buf, data->d_size);
123 data = elf_rawdata(scn, data);
142 ElfuElf* elfu_mFromElf(Elf *e)
146 size_t i, numPhdr, numShdr;
147 ElfuScn **secArray = NULL;
150 if (elfu_eCheck(e)) {
154 me = malloc(sizeof(ElfuElf));
156 ELFU_WARN("elfu_mFromElf: malloc() failed for ElfuElf.\n");
162 CIRCLEQ_INIT(&me->scnList);
163 CIRCLEQ_INIT(&me->phdrList);
166 me->elfclass = gelf_getclass(e);
167 assert(me->elfclass != ELFCLASSNONE);
168 assert(gelf_getehdr(e, &me->ehdr) == &me->ehdr);
171 /* Get the section string table index */
172 if (elf_getshdrstrndx(e, &shstrndx) != 0) {
178 assert(!elf_getphdrnum(e, &numPhdr));
179 for (i = 0; i < numPhdr; i++) {
183 assert(gelf_getphdr(e, i, &phdr) == &phdr);
185 mp = modelFromPhdr(&phdr);
190 CIRCLEQ_INSERT_TAIL(&me->phdrList, mp, elem);
195 assert(!elf_getshdrnum(e, &numShdr));
197 secArray = malloc((numShdr - 1) * sizeof(*secArray));
199 ELFU_WARN("elfu_mFromElf: malloc() failed for secArray.\n");
203 for (i = 1; i < numShdr; i++) {
207 scn = elf_getscn(e, i);
210 ms = modelFromSection(scn);
223 /* Find sh_link dependencies */
224 for (i = 0; i < numShdr - 1; i++) {
225 ElfuScn *ms = secArray[i];
227 if (ms->shdr.sh_link > 0) {
228 ms->link = secArray[ms->shdr.sh_link - 1];
233 /* Sort sections by file offset */
234 qsort(secArray, numShdr - 1, sizeof(*secArray), cmpScnOffs);
237 /* Find PHDR -> Section dependencies (needs sorted sections) */
238 for (i = 0; i < numShdr - 1; i++) {
239 ElfuScn *ms = secArray[i];
241 ElfuPhdr *parent = parentPhdr(me, ms);
244 CIRCLEQ_INSERT_TAIL(&parent->phdrToScnList, ms, elemPhdrToScn);
249 /* Put sections into list of all sections */
250 for (i = 0; i < numShdr - 1; i++) {
251 CIRCLEQ_INSERT_TAIL(&me->scnList, secArray[i], elem);
264 // TODO: Free data structures
267 ELFU_WARN("elfu_mFromElf: Failed to load file.\n");