1 | /* Code for loading Linux executables. Mostly linux kernel code. */ |
2 | |
3 | #include "qemu/osdep.h" |
4 | |
5 | #include "qemu.h" |
6 | |
7 | #define NGROUPS 32 |
8 | |
9 | /* ??? This should really be somewhere else. */ |
10 | abi_long memcpy_to_target(abi_ulong dest, const void *src, |
11 | unsigned long len) |
12 | { |
13 | void *host_ptr; |
14 | |
15 | host_ptr = lock_user(VERIFY_WRITE, dest, len, 0); |
16 | if (!host_ptr) |
17 | return -TARGET_EFAULT; |
18 | memcpy(host_ptr, src, len); |
19 | unlock_user(host_ptr, dest, 1); |
20 | return 0; |
21 | } |
22 | |
23 | static int count(char ** vec) |
24 | { |
25 | int i; |
26 | |
27 | for(i = 0; *vec; i++) { |
28 | vec++; |
29 | } |
30 | |
31 | return(i); |
32 | } |
33 | |
34 | static int prepare_binprm(struct linux_binprm *bprm) |
35 | { |
36 | struct stat st; |
37 | int mode; |
38 | int retval; |
39 | |
40 | if(fstat(bprm->fd, &st) < 0) { |
41 | return(-errno); |
42 | } |
43 | |
44 | mode = st.st_mode; |
45 | if(!S_ISREG(mode)) { /* Must be regular file */ |
46 | return(-EACCES); |
47 | } |
48 | if(!(mode & 0111)) { /* Must have at least one execute bit set */ |
49 | return(-EACCES); |
50 | } |
51 | |
52 | bprm->e_uid = geteuid(); |
53 | bprm->e_gid = getegid(); |
54 | |
55 | /* Set-uid? */ |
56 | if(mode & S_ISUID) { |
57 | bprm->e_uid = st.st_uid; |
58 | } |
59 | |
60 | /* Set-gid? */ |
61 | /* |
62 | * If setgid is set but no group execute bit then this |
63 | * is a candidate for mandatory locking, not a setgid |
64 | * executable. |
65 | */ |
66 | if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) { |
67 | bprm->e_gid = st.st_gid; |
68 | } |
69 | |
70 | retval = read(bprm->fd, bprm->buf, BPRM_BUF_SIZE); |
71 | if (retval < 0) { |
72 | perror("prepare_binprm" ); |
73 | exit(-1); |
74 | } |
75 | if (retval < BPRM_BUF_SIZE) { |
76 | /* Make sure the rest of the loader won't read garbage. */ |
77 | memset(bprm->buf + retval, 0, BPRM_BUF_SIZE - retval); |
78 | } |
79 | return retval; |
80 | } |
81 | |
82 | /* Construct the envp and argv tables on the target stack. */ |
83 | abi_ulong loader_build_argptr(int envc, int argc, abi_ulong sp, |
84 | abi_ulong stringp, int push_ptr) |
85 | { |
86 | TaskState *ts = (TaskState *)thread_cpu->opaque; |
87 | int n = sizeof(abi_ulong); |
88 | abi_ulong envp; |
89 | abi_ulong argv; |
90 | |
91 | sp -= (envc + 1) * n; |
92 | envp = sp; |
93 | sp -= (argc + 1) * n; |
94 | argv = sp; |
95 | if (push_ptr) { |
96 | /* FIXME - handle put_user() failures */ |
97 | sp -= n; |
98 | put_user_ual(envp, sp); |
99 | sp -= n; |
100 | put_user_ual(argv, sp); |
101 | } |
102 | sp -= n; |
103 | /* FIXME - handle put_user() failures */ |
104 | put_user_ual(argc, sp); |
105 | ts->info->arg_start = stringp; |
106 | while (argc-- > 0) { |
107 | /* FIXME - handle put_user() failures */ |
108 | put_user_ual(stringp, argv); |
109 | argv += n; |
110 | stringp += target_strlen(stringp) + 1; |
111 | } |
112 | ts->info->arg_end = stringp; |
113 | /* FIXME - handle put_user() failures */ |
114 | put_user_ual(0, argv); |
115 | while (envc-- > 0) { |
116 | /* FIXME - handle put_user() failures */ |
117 | put_user_ual(stringp, envp); |
118 | envp += n; |
119 | stringp += target_strlen(stringp) + 1; |
120 | } |
121 | /* FIXME - handle put_user() failures */ |
122 | put_user_ual(0, envp); |
123 | |
124 | return sp; |
125 | } |
126 | |
127 | int loader_exec(int fdexec, const char *filename, char **argv, char **envp, |
128 | struct target_pt_regs * regs, struct image_info *infop, |
129 | struct linux_binprm *bprm) |
130 | { |
131 | int retval; |
132 | |
133 | bprm->fd = fdexec; |
134 | bprm->filename = (char *)filename; |
135 | bprm->argc = count(argv); |
136 | bprm->argv = argv; |
137 | bprm->envc = count(envp); |
138 | bprm->envp = envp; |
139 | |
140 | retval = prepare_binprm(bprm); |
141 | |
142 | if(retval>=0) { |
143 | if (bprm->buf[0] == 0x7f |
144 | && bprm->buf[1] == 'E' |
145 | && bprm->buf[2] == 'L' |
146 | && bprm->buf[3] == 'F') { |
147 | retval = load_elf_binary(bprm, infop); |
148 | #if defined(TARGET_HAS_BFLT) |
149 | } else if (bprm->buf[0] == 'b' |
150 | && bprm->buf[1] == 'F' |
151 | && bprm->buf[2] == 'L' |
152 | && bprm->buf[3] == 'T') { |
153 | retval = load_flt_binary(bprm, infop); |
154 | #endif |
155 | } else { |
156 | return -ENOEXEC; |
157 | } |
158 | } |
159 | |
160 | if(retval>=0) { |
161 | /* success. Initialize important registers */ |
162 | do_init_thread(regs, infop); |
163 | return retval; |
164 | } |
165 | |
166 | return(retval); |
167 | } |
168 | |