1 /*- 2 * Copyright (c) 2014, 2015 The FreeBSD Foundation. 3 * Copyright (c) 2014, 2017 Andrew Turner. 4 * Copyright (c) 2018 Olivier Houchard 5 * All rights reserved. 6 * 7 * This software was developed by Andrew Turner under 8 * sponsorship from the FreeBSD Foundation. 9 * 10 * Portions of this software were developed by Konstantin Belousov 11 * under sponsorship from the FreeBSD Foundation. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #include <sys/cdefs.h> 36 #define __ELF_WORD_SIZE 32 37 38 #include <sys/param.h> 39 #include <sys/kernel.h> 40 #include <sys/systm.h> 41 #include <sys/exec.h> 42 #include <sys/imgact.h> 43 #include <sys/linker.h> 44 #include <sys/proc.h> 45 #include <sys/reg.h> 46 #include <sys/sysent.h> 47 #include <sys/imgact_elf.h> 48 #include <sys/syscall.h> 49 #include <sys/signalvar.h> 50 #include <sys/vnode.h> 51 52 #include <machine/elf.h> 53 #include <machine/pcb.h> 54 #ifdef VFP 55 #include <machine/vfp.h> 56 #endif 57 58 #include <compat/freebsd32/freebsd32_util.h> 59 60 #define FREEBSD32_MINUSER 0x00001000 61 #define FREEBSD32_MAXUSER ((1ul << 32) - PAGE_SIZE) 62 #define FREEBSD32_SHAREDPAGE (FREEBSD32_MAXUSER - PAGE_SIZE) 63 #define FREEBSD32_USRSTACK FREEBSD32_SHAREDPAGE 64 65 extern const char *freebsd32_syscallnames[]; 66 67 extern char aarch32_sigcode[]; 68 extern int sz_aarch32_sigcode; 69 70 static int freebsd32_fetch_syscall_args(struct thread *td); 71 static void freebsd32_setregs(struct thread *td, struct image_params *imgp, 72 u_long stack); 73 static void freebsd32_set_syscall_retval(struct thread *, int); 74 75 static bool elf32_arm_abi_supported(struct image_params *, int32_t *, 76 uint32_t *); 77 78 extern void freebsd32_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask); 79 80 u_long __read_frequently elf32_hwcap; 81 u_long __read_frequently elf32_hwcap2; 82 83 static struct sysentvec elf32_freebsd_sysvec = { 84 .sv_size = SYS_MAXSYSCALL, 85 .sv_table = freebsd32_sysent, 86 .sv_fixup = elf32_freebsd_fixup, 87 .sv_sendsig = freebsd32_sendsig, 88 .sv_sigcode = aarch32_sigcode, 89 .sv_szsigcode = &sz_aarch32_sigcode, 90 .sv_name = "FreeBSD ELF32", 91 .sv_coredump = elf32_coredump, 92 .sv_elf_core_osabi = ELFOSABI_FREEBSD, 93 .sv_elf_core_abi_vendor = FREEBSD_ABI_VENDOR, 94 .sv_elf_core_prepare_notes = elf32_prepare_notes, 95 .sv_minsigstksz = MINSIGSTKSZ, 96 .sv_minuser = FREEBSD32_MINUSER, 97 .sv_maxuser = FREEBSD32_MAXUSER, 98 .sv_usrstack = FREEBSD32_USRSTACK, 99 .sv_psstrings = FREEBSD32_PS_STRINGS, 100 .sv_psstringssz = sizeof(struct freebsd32_ps_strings), 101 .sv_stackprot = VM_PROT_READ | VM_PROT_WRITE, 102 .sv_copyout_auxargs = elf32_freebsd_copyout_auxargs, 103 .sv_copyout_strings = freebsd32_copyout_strings, 104 .sv_setregs = freebsd32_setregs, 105 .sv_fixlimit = NULL, // XXX 106 .sv_maxssiz = NULL, 107 .sv_flags = SV_ABI_FREEBSD | SV_ILP32 | SV_SHP | SV_TIMEKEEP | 108 SV_RNG_SEED_VER, 109 .sv_set_syscall_retval = freebsd32_set_syscall_retval, 110 .sv_fetch_syscall_args = freebsd32_fetch_syscall_args, 111 .sv_syscallnames = freebsd32_syscallnames, 112 .sv_shared_page_base = FREEBSD32_SHAREDPAGE, 113 .sv_shared_page_len = PAGE_SIZE, 114 .sv_schedtail = NULL, 115 .sv_thread_detach = NULL, 116 .sv_trap = NULL, 117 .sv_hwcap = &elf32_hwcap, 118 .sv_hwcap2 = &elf32_hwcap2, 119 .sv_onexec_old = exec_onexec_old, 120 .sv_onexit = exit_onexit, 121 .sv_regset_begin = SET_BEGIN(__elfN(regset)), 122 .sv_regset_end = SET_LIMIT(__elfN(regset)), 123 }; 124 INIT_SYSENTVEC(elf32_sysvec, &elf32_freebsd_sysvec); 125 126 static Elf32_Brandinfo freebsd32_brand_info = { 127 .brand = ELFOSABI_FREEBSD, 128 .machine = EM_ARM, 129 .compat_3_brand = "FreeBSD", 130 .interp_path = "/libexec/ld-elf.so.1", 131 .sysvec = &elf32_freebsd_sysvec, 132 .interp_newpath = "/libexec/ld-elf32.so.1", 133 .brand_note = &elf32_freebsd_brandnote, 134 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE, 135 .header_supported= elf32_arm_abi_supported, 136 }; 137 138 SYSINIT(elf32, SI_SUB_EXEC, SI_ORDER_FIRST, 139 (sysinit_cfunc_t)elf32_insert_brand_entry, &freebsd32_brand_info); 140 141 static bool 142 elf32_arm_abi_supported(struct image_params *imgp, int32_t *osrel __unused, 143 uint32_t *fctl0 __unused) 144 { 145 const Elf32_Ehdr *hdr; 146 147 /* Check if we support AArch32 */ 148 if (ID_AA64PFR0_EL0_VAL(READ_SPECIALREG(id_aa64pfr0_el1)) != 149 ID_AA64PFR0_EL0_64_32) 150 return (false); 151 152 #define EF_ARM_EABI_FREEBSD_MIN EF_ARM_EABI_VER4 153 hdr = (const Elf32_Ehdr *)imgp->image_header; 154 if (EF_ARM_EABI_VERSION(hdr->e_flags) < EF_ARM_EABI_FREEBSD_MIN) { 155 if (bootverbose) 156 uprintf("Attempting to execute non EABI binary " 157 "(rev %d) image %s", 158 EF_ARM_EABI_VERSION(hdr->e_flags), 159 imgp->args->fname); 160 return (false); 161 } 162 163 return (true); 164 } 165 166 static int 167 freebsd32_fetch_syscall_args(struct thread *td) 168 { 169 struct proc *p; 170 register_t *ap; 171 struct syscall_args *sa; 172 int error, i, nap, narg; 173 unsigned int args[4]; 174 175 nap = 4; 176 p = td->td_proc; 177 ap = td->td_frame->tf_x; 178 sa = &td->td_sa; 179 180 /* r7 is the syscall id */ 181 sa->code = td->td_frame->tf_x[7]; 182 sa->original_code = sa->code; 183 184 if (sa->code == SYS_syscall) { 185 sa->code = *ap++; 186 nap--; 187 } else if (sa->code == SYS___syscall) { 188 sa->code = ap[1]; 189 nap -= 2; 190 ap += 2; 191 } 192 193 if (sa->code >= p->p_sysent->sv_size) 194 sa->callp = &p->p_sysent->sv_table[0]; 195 else 196 sa->callp = &p->p_sysent->sv_table[sa->code]; 197 198 narg = sa->callp->sy_narg; 199 for (i = 0; i < nap; i++) 200 sa->args[i] = ap[i]; 201 if (narg > nap) { 202 if (narg - nap > nitems(args)) 203 panic("Too many system call arguiments"); 204 error = copyin((void *)td->td_frame->tf_x[13], args, 205 (narg - nap) * sizeof(int)); 206 if (error != 0) 207 return (error); 208 for (i = 0; i < (narg - nap); i++) 209 sa->args[i + nap] = args[i]; 210 } 211 212 td->td_retval[0] = 0; 213 td->td_retval[1] = 0; 214 215 return (0); 216 } 217 218 static void 219 freebsd32_set_syscall_retval(struct thread *td, int error) 220 { 221 struct trapframe *frame; 222 223 frame = td->td_frame; 224 switch (error) { 225 case 0: 226 frame->tf_x[0] = td->td_retval[0]; 227 frame->tf_x[1] = td->td_retval[1]; 228 frame->tf_spsr &= ~PSR_C; 229 break; 230 case ERESTART: 231 /* 232 * Reconstruct the pc to point at the swi. 233 */ 234 if ((frame->tf_spsr & PSR_T) != 0) 235 frame->tf_elr -= 2; //THUMB_INSN_SIZE; 236 else 237 frame->tf_elr -= 4; //INSN_SIZE; 238 break; 239 case EJUSTRETURN: 240 /* nothing to do */ 241 break; 242 default: 243 frame->tf_x[0] = error; 244 frame->tf_spsr |= PSR_C; 245 break; 246 } 247 } 248 249 static void 250 freebsd32_setregs(struct thread *td, struct image_params *imgp, 251 uintptr_t stack) 252 { 253 struct trapframe *tf = td->td_frame; 254 struct pcb *pcb = td->td_pcb; 255 256 memset(tf, 0, sizeof(struct trapframe)); 257 258 /* 259 * We need to set x0 for init as it doesn't call 260 * cpu_set_syscall_retval to copy the value. We also 261 * need to set td_retval for the cases where we do. 262 */ 263 tf->tf_x[0] = stack; 264 /* SP_usr is mapped to x13 */ 265 tf->tf_x[13] = stack; 266 /* LR_usr is mapped to x14 */ 267 tf->tf_x[14] = imgp->entry_addr; 268 tf->tf_elr = imgp->entry_addr; 269 tf->tf_spsr = PSR_M_32; 270 if ((uint32_t)imgp->entry_addr & 1) 271 tf->tf_spsr |= PSR_T; 272 273 #ifdef VFP 274 vfp_reset_state(td, pcb); 275 #endif 276 277 /* 278 * Clear debug register state. It is not applicable to the new process. 279 */ 280 bzero(&pcb->pcb_dbg_regs, sizeof(pcb->pcb_dbg_regs)); 281 } 282 283 void 284 elf32_dump_thread(struct thread *td, void *dst, size_t *off) 285 { 286 } 287