1 #include "inc.h" 2 #include <assert.h> 3 #include <sys/exec.h> 4 #include <libexec.h> 5 #include <minix/param.h> 6 #include <machine/vmparam.h> 7 8 static int do_exec(int proc_e, char *exec, size_t exec_len, char *progname, 9 char *frame, int frame_len, vir_bytes ps_str); 10 static int exec_restart(int proc_e, int result, vir_bytes pc, vir_bytes ps_str); 11 static int read_seg(struct exec_info *execi, off_t off, 12 vir_bytes seg_addr, size_t seg_bytes); 13 14 /* Array of loaders for different object formats */ 15 static struct exec_loaders { 16 libexec_exec_loadfunc_t load_object; 17 } const exec_loaders[] = { 18 { libexec_load_elf }, 19 { NULL } 20 }; 21 22 int srv_execve(int proc_e, char *exec, size_t exec_len, char **argv, 23 char **envp) 24 { 25 size_t frame_size = 0; /* Size of the new initial stack. */ 26 int argc = 0; /* Argument count. */ 27 int envc = 0; /* Environment count */ 28 char overflow = 0; /* No overflow yet. */ 29 char *frame; 30 struct ps_strings *psp; 31 int vsp = 0; /* (virtual) Stack pointer in new address space. */ 32 33 char *progname; 34 int r; 35 36 minix_stack_params(argv[0], argv, envp, &frame_size, &overflow, 37 &argc, &envc); 38 39 /* The party is off if there is an overflow. */ 40 if (overflow) { 41 errno = E2BIG; 42 return -1; 43 } 44 45 /* Allocate space for the stack frame. */ 46 if ((frame = (char *) sbrk(frame_size)) == (char *) -1) { 47 errno = E2BIG; 48 return -1; 49 } 50 51 minix_stack_fill(argv[0], argc, argv, envc, envp, frame_size, frame, 52 &vsp, &psp); 53 54 (progname=strrchr(argv[0], '/')) ? progname++ : (progname=argv[0]); 55 56 r = do_exec(proc_e, exec, exec_len, progname, frame, frame_size, 57 vsp + ((char *)psp - frame)); 58 59 /* Failure, return the memory used for the frame and exit. */ 60 (void) sbrk(-frame_size); 61 62 return r; 63 } 64 65 66 static int do_exec(int proc_e, char *exec, size_t exec_len, char *progname, 67 char *frame, int frame_len, vir_bytes ps_str) 68 { 69 int r; 70 vir_bytes vsp; 71 struct exec_info execi; 72 int i; 73 74 memset(&execi, 0, sizeof(execi)); 75 76 execi.stack_high = kinfo.user_sp; 77 execi.stack_size = DEFAULT_STACK_LIMIT; 78 execi.proc_e = proc_e; 79 execi.hdr = exec; 80 execi.filesize = execi.hdr_len = exec_len; 81 strncpy(execi.progname, progname, PROC_NAME_LEN-1); 82 execi.progname[PROC_NAME_LEN-1] = '\0'; 83 execi.frame_len = frame_len; 84 85 /* callback functions and data */ 86 execi.copymem = read_seg; 87 execi.clearproc = libexec_clearproc_vm_procctl; 88 execi.clearmem = libexec_clear_sys_memset; 89 execi.allocmem_prealloc_cleared = libexec_alloc_mmap_prealloc_cleared; 90 execi.allocmem_prealloc_junk = libexec_alloc_mmap_prealloc_junk; 91 execi.allocmem_ondemand = libexec_alloc_mmap_ondemand; 92 93 for(i = 0; exec_loaders[i].load_object != NULL; i++) { 94 r = (*exec_loaders[i].load_object)(&execi); 95 /* Loaded successfully, so no need to try other loaders */ 96 if (r == OK) break; 97 } 98 99 /* No exec loader could load the object */ 100 if (r != OK) { 101 printf("RS: do_exec: loading error %d\n", r); 102 return r; 103 } 104 105 /* Inform PM */ 106 if((r = libexec_pm_newexec(execi.proc_e, &execi)) != OK) 107 return r; 108 109 /* Patch up stack and copy it from RS to new core image. */ 110 vsp = execi.stack_high - frame_len; 111 r = sys_datacopy(SELF, (vir_bytes) frame, 112 proc_e, (vir_bytes) vsp, (phys_bytes)frame_len); 113 if (r != OK) { 114 printf("do_exec: copying out new stack failed: %d\n", r); 115 exec_restart(proc_e, r, execi.pc, ps_str); 116 return r; 117 } 118 119 return exec_restart(proc_e, OK, execi.pc, ps_str); 120 } 121 122 /*===========================================================================* 123 * exec_restart * 124 *===========================================================================*/ 125 static int exec_restart(int proc_e, int result, vir_bytes pc, vir_bytes ps_str) 126 { 127 int r; 128 message m; 129 130 memset(&m, 0, sizeof(m)); 131 m.m_type = PM_EXEC_RESTART; 132 m.m_rs_pm_exec_restart.endpt = proc_e; 133 m.m_rs_pm_exec_restart.result = result; 134 m.m_rs_pm_exec_restart.pc = pc; 135 m.m_rs_pm_exec_restart.ps_str = ps_str; 136 137 r = ipc_sendrec(PM_PROC_NR, &m); 138 if (r != OK) 139 return r; 140 141 return m.m_type; 142 } 143 144 /*===========================================================================* 145 * read_seg * 146 *===========================================================================*/ 147 static int read_seg( 148 struct exec_info *execi, /* various data needed for exec */ 149 off_t off, /* offset in file */ 150 vir_bytes seg_addr, /* address to load segment */ 151 size_t seg_bytes /* how much is to be transferred? */ 152 ) 153 { 154 /* 155 * The byte count on read is usually smaller than the segment count, because 156 * a segment is padded out to a click multiple, and the data segment is only 157 * partially initialized. 158 */ 159 160 int r; 161 162 if (off+seg_bytes > execi->hdr_len) return ENOEXEC; 163 if((r= sys_datacopy(SELF, ((vir_bytes)execi->hdr)+off, 164 execi->proc_e, seg_addr, seg_bytes)) != OK) { 165 printf("RS: exec read_seg: copy 0x%x bytes into %i at 0x%08lx failed: %i\n", 166 (int) seg_bytes, execi->proc_e, seg_addr, r); 167 } 168 return r; 169 } 170