Merge pull request #549 from cpavlina/aarch64_reloc

bfelf_loader: implement relocations for aarch64
Bareflank · Dec 7, 2017 · 83a1efe · 83a1efe
2 parents 17aa24d + c707954
commit 83a1efe
Show file tree

Hide file tree

Showing 4 changed files with 383 additions and 57 deletions.
diff --git a/bfelf_loader/CMakeLists.txt b/bfelf_loader/CMakeLists.txt
@@ -22,3 +22,5 @@ project(bfelf_loader C CXX)
 set(TIDY_EXCLUSIONS ,-cppcoreguidelines-pro-type-const-cast)
 
 install(FILES include/bfelf_loader.h DESTINATION ${BUILD_SYSROOT_OS}/include)
+install(FILES include/bfelf_loader_reloc_x64.h DESTINATION ${BUILD_SYSROOT_OS}/include)
+install(FILES include/bfelf_loader_reloc_aarch64.h DESTINATION ${BUILD_SYSROOT_OS}/include)
diff --git a/bfelf_loader/include/bfelf_loader.h b/bfelf_loader/include/bfelf_loader.h
@@ -30,6 +30,7 @@
 #include <bfplatform.h>
 #include <bfconstants.h>
 #include <bferrorcodes.h>
+#include <bfarch.h>
 
 #pragma pack(push, 1)
 
@@ -730,21 +731,6 @@ struct bfelf_sym {
 /* ELF Relocations                                                                                */
 /* ---------------------------------------------------------------------------------------------- */
 
-/*
- * System V ABI 64bit Relocations
- *
- * The following is defined in the ELF 64bit file format specification:
- * http://www.x86-64.org/documentation/abi.pdf, page 71
- *
- * @cond
- */
-#define BFR_X86_64_64 bfscast(bfelf64_xword, 1)
-#define BFR_X86_64_GLOB_DAT bfscast(bfelf64_xword, 6)
-#define BFR_X86_64_JUMP_SLOT bfscast(bfelf64_xword, 7)
-#define BFR_X86_64_RELATIVE bfscast(bfelf64_xword, 8)
-
-/* @endcond */
-
 /*
  * ELF Relocation
  *
@@ -789,6 +775,7 @@ struct bfelf_rela {
 
 /* @endcond */
 
+
 /* ---------------------------------------------------------------------------------------------- */
 /* ELF Program Header                                                                             */
 /* ---------------------------------------------------------------------------------------------- */
@@ -1020,55 +1007,36 @@ private_get_sym_global(
 /* ELF Relocations Implementation                                                                 */
 /* ---------------------------------------------------------------------------------------------- */
 
-/* @cond */
+/*
+ * Forward declarations required by relocator
+ *
+ * @cond
+ */
 
 static inline int64_t
-private_relocate_symbol(
-    struct bfelf_loader_t *loader, struct bfelf_file_t *ef, const struct bfelf_rela *rela)
-{
-    const char *str = nullptr;
-    const struct bfelf_sym *found_sym = nullptr;
-    struct bfelf_file_t *found_ef = ef;
-    bfelf64_addr *ptr = bfrcast(bfelf64_addr *, ef->exec_addr + rela->r_offset - ef->start_addr);
-
-    if (BFELF_REL_TYPE(rela->r_info) == BFR_X86_64_RELATIVE) {
-        *ptr = bfrcast(bfelf64_addr, ef->exec_virt + rela->r_addend);
-        return BFELF_SUCCESS;
-    }
-
-    found_sym = &(ef->symtab[BFELF_REL_SYM(rela->r_info)]);
-
-    if (BFELF_SYM_BIND(found_sym->st_info) == bfstb_weak) {
-        found_ef = nullptr;
-    }
-
-    if (found_sym->st_value == 0 || found_ef == nullptr) {
-        int64_t ret = 0;
-        str = &(ef->strtab[found_sym->st_name]);
-
-        ret = private_get_sym_global(loader, str, &found_ef, &found_sym);
-        if (ret != BFELF_SUCCESS) {
-            return ret;
-        }
-    }
+private_get_sym_global(
+    const struct bfelf_loader_t *loader, const char *name,
+    struct bfelf_file_t **ef_found, const struct bfelf_sym **sym);
 
-    *ptr = bfrcast(bfelf64_addr, found_ef->exec_virt + found_sym->st_value);
+/* @endcond */
 
-    switch (BFELF_REL_TYPE(rela->r_info)) {
-        case BFR_X86_64_64:
-            *ptr += bfscast(bfelf64_addr, rela->r_addend);
-            break;
+/*
+ * Relocation definitions and relocators
+ *
+ * @cond
+ */
 
-        case BFR_X86_64_GLOB_DAT:
-        case BFR_X86_64_JUMP_SLOT:
-            break;
+#if defined(BF_AARCH64)
+#   include <bfelf_loader_reloc_aarch64.h>
+#elif defined(BF_X64)
+#   include <bfelf_loader_reloc_x64.h>
+#else
+#   error "Unsupported architecture"
+#endif
 
-        default:
-            return bfunsupported_rel(str);
-    }
+/* @endcond */
 
-    return BFELF_SUCCESS;
-}
+/* @cond */
 
 static inline int64_t
 private_relocate_symbols(struct bfelf_loader_t *loader, struct bfelf_file_t *ef)
@@ -1154,9 +1122,17 @@ private_check_support(struct bfelf_file_t *ef)
         return bfunsupported_file("file must be an executable or shared library");
     }
 
+#ifdef BF_AARCH64
+    if (ef->ehdr->e_machine != bfem_aarch64) {
+        return bfunsupported_file("file must be compiled for aarch64");
+    }
+#endif
+
+#ifdef BF_X64
     if (ef->ehdr->e_machine != bfem_x86_64) {
         return bfunsupported_file("file must be compiled for x86_64");
     }
+#endif
 
     if (ef->ehdr->e_version != bfev_current) {
         return bfunsupported_file("unsupported version");

diff --git a/bfelf_loader/include/bfelf_loader_reloc_aarch64.h b/bfelf_loader/include/bfelf_loader_reloc_aarch64.h
@@ -0,0 +1,255 @@
+/*
+ * Bareflank Hypervisor
+ * Copyright (C) 2017 Assured Information Security, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file bfelf_loader_reloc_aarch64.h
+ */
+
+/*
+ * AArch64 Relocations
+ *
+ * The following is defined in the "ELF for the ARM 64-bit architecture"
+ * specification:
+ * http://infocenter.arm.com/help/topic/com.arm.doc.ihi0056b/IHI0056B_aaelf64.pdf
+ *
+ * @cond
+ */
+
+/* ---------------------------------------------------------------------------------------------- */
+/* Miscellaneous relocations                                                                      */
+/* ---------------------------------------------------------------------------------------------- */
+#define BFR_AARCH64_NONE bfscast(bfelf64_xword, 0)
+
+/* ---------------------------------------------------------------------------------------------- */
+/* Static data relocations                                                                        */
+/* ---------------------------------------------------------------------------------------------- */
+/* Data relocations */
+#define BFR_AARCH64_ABS64 bfscast(bfelf64_xword, 257)
+#define BFR_AARCH64_ABS32 bfscast(bfelf64_xword, 258)
+#define BFR_AARCH64_ABS16 bfscast(bfelf64_xword, 259)
+#define BFR_AARCH64_PREL64 bfscast(bfelf64_xword, 260)
+#define BFR_AARCH64_PREL32 bfscast(bfelf64_xword, 261)
+#define BFR_AARCH64_PREL16 bfscast(bfelf64_xword, 262)
+
+/* ---------------------------------------------------------------------------------------------- */
+/* Static AArch64 relocations                                                                     */
+/* ---------------------------------------------------------------------------------------------- */
+/* Group relocations to create an unsigned data value or address inline */
+#define BFR_AARCH64_MOVW_UABS_G0 bfscast(bfelf64_xword, 263)
+#define BFR_AARCH64_MOVW_UABS_G0_NC bfscast(bfelf64_xword, 264)
+#define BFR_AARCH64_MOVW_UABS_G1 bfscast(bfelf64_xword, 265)
+#define BFR_AARCH64_MOVW_UABS_G1_NC bfscast(bfelf64_xword, 266)
+#define BFR_AARCH64_MOVW_UABS_G2 bfscast(bfelf64_xword, 267)
+#define BFR_AARCH64_MOVW_UABS_G2_NC bfscast(bfelf64_xword, 268)
+#define BFR_AARCH64_MOVW_UABS_G3 bfscast(bfelf64_xword, 269)
+
+/* Group relocations to create a signed data or offset value inline */
+#define BFR_AARCH64_MOVW_SABS_G0 bfscast(bfelf64_xword, 270)
+#define BFR_AARCH64_MOVW_SABS_G1 bfscast(bfelf64_xword, 271)
+#define BFR_AARCH64_MOVW_SABS_G2 bfscast(bfelf64_xword, 272)
+
+/* Relocations to generate PC-relative addresses */
+#define BFR_AARCH64_LD_PREL_LO19 bfscast(bfelf64_xword, 273)
+#define BFR_AARCH64_ADR_PREL_LO21 bfscast(bfelf64_xword, 274)
+#define BFR_AARCH64_ADR_PREL_PG_HI21 bfscast(bfelf64_xword, 275)
+#define BFR_AARCH64_ADR_PREL_PG_HI21_NC bfscast(bfelf64_xword, 276)
+#define BFR_AARCH64_ADD_ABS_LO12_NC bfscast(bfelf64_xword, 277)
+#define BFR_AARCH64_LDST8_ABS_LO12_NC bfscast(bfelf64_xword, 278)
+#define BFR_AARCH64_LDST16_ABS_LO12_NC bfscast(bfelf64_xword, 284)
+#define BFR_AARCH64_LDST32_ABS_LO12_NC bfscast(bfelf64_xword, 285)
+#define BFR_AARCH64_LDST64_ABS_LO12_NC bfscast(bfelf64_xword, 286)
+#define BFR_AARCH64_LDST128_ABS_LO12_NC bfscast(bfelf64_xword, 299)
+
+/* Relocations for control-flow instructions */
+#define BFR_AARCH64_TSTBR14 bfscast(bfelf64_xword, 279)
+#define BFR_AARCH64_CONDBR19 bfscast(bfelf64_xword, 280)
+#define BFR_AARCH64_JUMP26 bfscast(bfelf64_xword, 282)
+#define BFR_AARCH64_CALL26 bfscast(bfelf64_xword, 283)
+
+/* Group relocations to create a PC-relative offset inline */
+#define BFR_AARCH64_MOVW_PREL_G0 bfscast(bfelf64_xword, 287)
+#define BFR_AARCH64_MOVW_PREL_G0_NC bfscast(bfelf64_xword, 288)
+#define BFR_AARCH64_MOVW_PREL_G1 bfscast(bfelf64_xword, 289)
+#define BFR_AARCH64_MOVW_PREL_G1_NC bfscast(bfelf64_xword, 290)
+#define BFR_AARCH64_MOVW_PREL_G2 bfscast(bfelf64_xword, 291)
+#define BFR_AARCH64_MOVW_PREL_G2_NC bfscast(bfelf64_xword, 292)
+#define BFR_AARCH64_MOVW_PREL_G3 bfscast(bfelf64_xword, 293)
+
+/* Group relocations to create a GOT-relative offset inline */
+#define BFR_AARCH64_MOVW_GOTOFF_G0 bfscast(bfelf64_xword, 300)
+#define BFR_AARCH64_MOVW_GOTOFF_G0_NC bfscast(bfelf64_xword, 301)
+#define BFR_AARCH64_MOVW_GOTOFF_G1 bfscast(bfelf64_xword, 302)
+#define BFR_AARCH64_MOVW_GOTOFF_G1_NC bfscast(bfelf64_xword, 303)
+#define BFR_AARCH64_MOVW_GOTOFF_G2 bfscast(bfelf64_xword, 304)
+#define BFR_AARCH64_MOVW_GOTOFF_G2_NC bfscast(bfelf64_xword, 305)
+#define BFR_AARCH64_MOVW_GOTOFF_G3 bfscast(bfelf64_xword, 306)
+
+/* GOT-relative data relocations */
+#define BFR_AARCH64_GOTREL64 bfscast(bfelf64_xword, 307)
+#define BFR_AARCH64_GOTREL32 bfscast(bfelf64_xword, 308)
+
+/* GOT-relative instruction relocations */
+#define BFR_AARCH64_GOT_LD_PREL19 bfscast(bfelf64_xword, 309)
+#define BFR_AARCH64_LD64_GOTOFF_LO15 bfscast(bfelf64_xword, 310)
+#define BFR_AARCH64_ADR_GOT_PAGE bfscast(bfelf64_xword, 311)
+#define BFR_AARCH64_LD64_GOT_LO12_NC bfscast(bfelf64_xword, 312)
+#define BFR_AARCH64_LD64_GOTPAGE_LO15 bfscast(bfelf64_xword, 313)
+
+/* ---------------------------------------------------------------------------------------------- */
+/* Relocations for thread-local storage                                                           */
+/* ---------------------------------------------------------------------------------------------- */
+/* General dynamic TLS relocations */
+#define BFR_AARCH64_TLSGD_ADR_PREL21 bfscast(bfelf64_xword, 512)
+#define BFR_AARCH64_TLSGD_ADR_PAGE21 bfscast(bfelf64_xword, 513)
+#define BFR_AARCH64_TLSGD_ADD_LO12_NC bfscast(bfelf64_xword, 514)
+#define BFR_AARCH64_TLSGD_MOVW_G1 bfscast(bfelf64_xword, 515)
+#define BFR_AARCH64_TLSGD_MOVW_G0_NC bfscast(bfelf64_xword, 516)
+
+/* Local dynamic TLS relocations */
+#define BFR_AARCH64_TLSLD_ADR_PREL21 bfscast(bfelf64_xword, 517)
+#define BFR_AARCH64_TLSLD_ADR_PAGE21 bfscast(bfelf64_xword, 518)
+#define BFR_AARCH64_TLSLD_ADD_LO12_NC bfscast(bfelf64_xword, 519)
+#define BFR_AARCH64_TLSLD_MOVW_G1 bfscast(bfelf64_xword, 520)
+#define BFR_AARCH64_TLSLD_MOVW_G0_NC bfscast(bfelf64_xword, 521)
+#define BFR_AARCH64_TLSLD_LD_PREL19 bfscast(bfelf64_xword, 522)
+#define BFR_AARCH64_TLSLD_MOVW_DTPREL_G2 bfscast(bfelf64_xword, 523)
+#define BFR_AARCH64_TLSLD_MOVW_DTPREL_G1 bfscast(bfelf64_xword, 524)
+#define BFR_AARCH64_TLSLD_MOVW_DTPREL_G1_NC bfscast(bfelf64_xword, 525)
+#define BFR_AARCH64_TLSLD_MOVW_DTPREL_G0 bfscast(bfelf64_xword, 526)
+#define BFR_AARCH64_TLSLD_MOVW_DTPREL_G0_NC bfscast(bfelf64_xword, 527)
+#define BFR_AARCH64_TLSLD_ADD_DTPREL_HI12 bfscast(bfelf64_xword, 528)
+#define BFR_AARCH64_TLSLD_ADD_DTPREL_LO12 bfscast(bfelf64_xword, 529)
+#define BFR_AARCH64_TLSLD_ADD_DTPREL_LO12_NC bfscast(bfelf64_xword, 530)
+#define BFR_AARCH64_TLSLD_LDST8_DTPREL_LO12 bfscast(bfelf64_xword, 531)
+#define BFR_AARCH64_TLSLD_LDST8_DTPREL_LO12_NC bfscast(bfelf64_xword, 532)
+#define BFR_AARCH64_TLSLD_LDST16_DTPREL_LO12 bfscast(bfelf64_xword, 533)
+#define BFR_AARCH64_TLSLD_LDST16_DTPREL_LO12_NC bfscast(bfelf64_xword, 534)
+#define BFR_AARCH64_TLSLD_LDST32_DTPREL_LO12 bfscast(bfelf64_xword, 535)
+#define BFR_AARCH64_TLSLD_LDST32_DTPREL_LO12_NC bfscast(bfelf64_xword, 536)
+#define BFR_AARCH64_TLSLD_LDST64_DTPREL_LO12 bfscast(bfelf64_xword, 537)
+#define BFR_AARCH64_TLSLD_LDST64_DTPREL_LO12_NC bfscast(bfelf64_xword, 538)
+#define BFR_AARCH64_TLSLD_LDST128_DTPREL_LO12 bfscast(bfelf64_xword, 572)
+#define BFR_AARCH64_TLSLD_LDST128_DTPREL_LO12_NC bfscast(bfelf64_xword, 573)
+
+/* Initial exec TLS relocations */
+#define BFR_AARCH64_TLSIE_MOVW_GOTTPREP_G1 bfscast(bfelf64_xword, 539)
+#define BFR_AARCH64_TLSIE_MOVW_GOTTPREL_G0_NC bfscast(bfelf64_xword, 540)
+#define BFR_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21 bfscast(bfelf64_xword, 541)
+#define BFR_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC bfscast(bfelf64_xword, 542)
+#define BFR_AARCH64_TLSIE_LD_GOTTPREL_PREL19 bfscast(bfelf64_xword, 543)
+
+/* Local exec TLS relocations */
+#define BFR_AARCH64_TLSLE_MOVW_TPREL_G2 bfscast(bfelf64_xword, 544)
+#define BFR_AARCH64_TLSLE_MOVW_TPREL_G1 bfscast(bfelf64_xword, 545)
+#define BFR_AARCH64_TLSLE_MOVW_TPREL_G1_NC bfscast(bfelf64_xword, 546)
+#define BFR_AARCH64_TLSLE_MOVW_TPREL_G0 bfscast(bfelf64_xword, 547)
+#define BFR_AARCH64_TLSLE_MOVW_TPREL_G0_NC bfscast(bfelf64_xword, 548)
+#define BFR_AARCH64_TLSLE_ADD_TPREL_HI12 bfscast(bfelf64_xword, 549)
+#define BFR_AARCH64_TLSLE_ADD_TPREL_LO12 bfscast(bfelf64_xword, 550)
+#define BFR_AARCH64_TLSLE_ADD_TPREL_LO12_NC bfscast(bfelf64_xword, 551)
+#define BFR_AARCH64_TLSLE_LDST8_TPREL_LO12 bfscast(bfelf64_xword, 552)
+#define BFR_AARCH64_TLSLE_LDST8_TPREL_LO12_NC bfscast(bfelf64_xword, 553)
+#define BFR_AARCH64_TLSLE_LDST16_TPREL_LO12 bfscast(bfelf64_xword, 554)
+#define BFR_AARCH64_TLSLE_LDST16_TPREL_LO12_NC bfscast(bfelf64_xword, 555)
+#define BFR_AARCH64_TLSLE_LDST32_TPREL_LO12 bfscast(bfelf64_xword, 556)
+#define BFR_AARCH64_TLSLE_LDST32_TPREL_LO12_NC bfscast(bfelf64_xword, 557)
+#define BFR_AARCH64_TLSLE_LDST64_TPREL_LO12 bfscast(bfelf64_xword, 558)
+#define BFR_AARCH64_TLSLE_LDST64_TPREL_LO12_NC bfscast(bfelf64_xword, 559)
+#define BFR_AARCH64_TLSLE_LDST128_TPREL_LO12 bfscast(bfelf64_xword, 570)
+#define BFR_AARCH64_TLSLE_LDST128_TPREL_LO12_NC bfscast(bfelf64_xword, 571)
+
+/* TLS descriptor relocations */
+#define BFR_AARCH64_TLSDESC_LD_PREL19 bfscast(bfelf64_xword, 560)
+#define BFR_AARCH64_TLSDESC_ADR_PREL21 bfscast(bfelf64_xword, 561)
+#define BFR_AARCH64_TLSDESC_ADR_PAGE21 bfscast(bfelf64_xword, 562)
+#define BFR_AARCH64_TLSDESC_LD64_LO12 bfscast(bfelf64_xword, 563)
+#define BFR_AARCH64_TLSDESC_ADD_LO12 bfscast(bfelf64_xword, 564)
+#define BFR_AARCH64_TLSDESC_OFF_G1 bfscast(bfelf64_xword, 656)
+#define BFR_AARCH64_TLSDESC_OFF_G0_NC bfscast(bfelf64_xword, 566)
+#define BFR_AARCH64_TLSDESC_LDR bfscast(bfelf64_xword, 567)
+#define BFR_AARCH64_TLSDESC_ADD bfscast(bfelf64_xword, 568)
+#define BFR_AARCH64_TLSDESC_CALL bfscast(bfelf64_xword, 569)
+
+/* ---------------------------------------------------------------------------------------------- */
+/* Dynamic relocations                                                                            */
+/* ---------------------------------------------------------------------------------------------- */
+#define BFR_AARCH64_COPY bfscast(bfelf64_xword, 1024)
+#define BFR_AARCH64_GLOB_DAT bfscast(bfelf64_xword, 1025)
+#define BFR_AARCH64_JUMP_SLOT bfscast(bfelf64_xword, 1026)
+#define BFR_AARCH64_RELATIVE bfscast(bfelf64_xword, 1027)
+#define BFR_AARCH64_TLS_DTPREL64 bfscast(bfelf64_xword, 1028)
+#define BFR_AARCH64_TLS_DTPMOD64 bfscast(bfelf64_xword, 1029)
+#define BFR_AARCH64_TLS_TPREL64 bfscast(bfelf64_xword, 1030)
+#define BFR_AARCH64_TLSDESC bfscast(bfelf64_xword, 1031)
+#define BFR_AARCH64_IRELATIVE bfscast(bfelf64_xword, 1032)
+
+/* @endcond */
+
+/* ---------------------------------------------------------------------------------------------- */
+/* ELF Relocations Implementation                                                                 */
+/* ---------------------------------------------------------------------------------------------- */
+
+/* @cond */
+
+static inline int64_t
+private_relocate_symbol(
+    struct bfelf_loader_t *loader, struct bfelf_file_t *ef, const struct bfelf_rela *rela)
+{
+    const char *str = nullptr;
+    const struct bfelf_sym *found_sym = nullptr;
+    struct bfelf_file_t *found_ef = ef;
+    bfelf64_addr *ptr = bfrcast(bfelf64_addr *, ef->exec_addr + rela->r_offset - ef->start_addr);
+
+    if (BFELF_REL_TYPE(rela->r_info) == BFR_AARCH64_RELATIVE) {
+        *ptr = bfrcast(bfelf64_addr, ef->exec_virt + rela->r_addend);
+        return BFELF_SUCCESS;
+    }
+
+    found_sym = &(ef->symtab[BFELF_REL_SYM(rela->r_info)]);
+
+    if (BFELF_SYM_BIND(found_sym->st_info) == bfstb_weak) {
+        found_ef = nullptr;
+    }
+
+    if (found_sym->st_value == 0 || found_ef == nullptr) {
+        int64_t ret;
+
+        str = &(ef->strtab[found_sym->st_name]);
+        ret = private_get_sym_global(loader, str, &found_ef, &found_sym);
+
+        if (ret != BFELF_SUCCESS) {
+            return ret;
+        }
+    }
+
+    *ptr = bfrcast(bfelf64_addr, found_ef->exec_virt + found_sym->st_value);
+
+    switch (BFELF_REL_TYPE(rela->r_info)) {
+        case BFR_AARCH64_GLOB_DAT:
+        case BFR_AARCH64_JUMP_SLOT:
+            break;
+
+        default:
+            return bfunsupported_rel(str);
+    }
+
+    return BFELF_SUCCESS;
+}
+
+/* @endcond */