1 /* $OpenBSD: fxproc0.c,v 1.2 2021/12/13 16:56:49 deraadt Exp $ */
2 /*
3 * Copyright (c) 2018 Alexander Bluhm <bluhm@openbsd.org>
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17
18 #include <sys/types.h>
19 #include <sys/signal.h>
20 #include <sys/proc.h>
21 #include <sys/user.h>
22 #include <machine/fpu.h>
23 #include <machine/pcb.h>
24
25 #include <err.h>
26 #include <fcntl.h>
27 #include <kvm.h>
28 #include <limits.h>
29 #include <stdio.h>
30 #include <stdlib.h>
31 #include <unistd.h>
32
33 #define nitems(_a) (sizeof((_a)) / sizeof((_a)[0]))
34
35 void __dead usage(void);
36 void fenv_proc(kvm_t *, unsigned long);
37
38 void __dead
usage(void)39 usage(void)
40 {
41 fprintf(stderr, "usage: %s [-M core] [-N system]\n", getprogname());
42 exit(1);
43 }
44
45 int
main(int argc,char * argv[])46 main(int argc, char *argv[])
47 {
48 char errbuf[_POSIX2_LINE_MAX];
49 char *memf, *nlistf;
50 kvm_t *kd;
51 int ch;
52 struct nlist nl[] = { { .n_name = "_proc0" }, { .n_name = NULL } };
53
54 memf = nlistf = NULL;
55 while ((ch = getopt(argc, argv, "M:N:")) != -1) {
56 switch(ch) {
57 case 'M':
58 memf = optarg;
59 break;
60 case 'N':
61 nlistf = optarg;
62 break;
63 default:
64 usage();
65 }
66 }
67 argc -= optind;
68 argv += optind;
69 if (argc)
70 usage();
71
72 kd = kvm_openfiles(nlistf, memf, NULL, O_RDONLY, errbuf);
73 if (kd == NULL)
74 errx(1, "kvm_openfiles: %s", errbuf);
75 if (kvm_nlist(kd, nl) == -1)
76 errx(1, "kvm_nlist: %s", kvm_geterr(kd));
77 if (nl[0].n_type == 0)
78 errx(1, "name '%s' has type %d", nl[0].n_name, nl[0].n_type);
79 fenv_proc(kd, nl[0].n_value);
80
81 if (kvm_close(kd) == -1)
82 errx(1, "kvm_close: %s", kvm_geterr(kd));
83 return 0;
84 }
85
86 void
fenv_proc(kvm_t * kd,unsigned long p)87 fenv_proc(kvm_t *kd, unsigned long p)
88 {
89 struct proc proc;
90 struct user user;
91 struct fxsave64 *fxs = &user.u_pcb.pcb_savefpu.fp_fxsave;
92 size_t i;
93
94 if (kvm_read(kd, p, &proc, sizeof(proc)) == -1)
95 errx(1, "kvm_read proc: %s", kvm_geterr(kd));
96 if (kvm_read(kd, (u_long)proc.p_addr, &user, sizeof(user)) == -1)
97 errx(1, "kvm_read user: %s", kvm_geterr(kd));
98
99 if (fxs != &fxs->fx_fcw)
100 errx(1, "fxsave start %p, fx_fcw start %p",
101 &fxs, &fxs->fx_fcw);
102 printf("fcw\t%04x\n", fxs->fx_fcw);
103 printf("fsw\t%04x\n", fxs->fx_fsw);
104 printf("ftw\t%02x\n", fxs->fx_ftw);
105 printf("unused1\t%02x\n", fxs->fx_unused1);
106 printf("fop\t%04x\n", fxs->fx_fop);
107 printf("rip\t%016llx\n", fxs->fx_rip);
108 printf("rdp\t%016llx\n", fxs->fx_rdp);
109 printf("mxcsr\t%08x\n", fxs->fx_mxcsr);
110 printf("mxcsr_mask\t%08x\n", fxs->fx_mxcsr_mask);
111 if (&fxs->fx_mxcsr_mask + 1 != fxs->fx_st)
112 errx(1, "fx_mxcsr_mask end %p, fx_st start %p",
113 &fxs->fx_mxcsr_mask + 1, fxs->fx_st);
114 for (i = 0; i < nitems(fxs->fx_st); i++)
115 printf("st[%zu]\t%016llx:%016llx\n", i,
116 fxs->fx_st[i][1], fxs->fx_st[i][0]);
117 if (&fxs->fx_st[i] != fxs->fx_xmm)
118 errx(1, "fx_st end %p, fx_xmm start %p",
119 &fxs->fx_st[i], fxs->fx_xmm);
120 for (i = 0; i < nitems(fxs->fx_xmm); i++)
121 printf("xmm[%zu]\t%016llx:%016llx\n", i,
122 fxs->fx_xmm[i][1], fxs->fx_xmm[i][0]);
123 if (&fxs->fx_xmm[i] != fxs->fx_unused3)
124 errx(1, "fx_xmm end %p, fx_unused3 start %p",
125 &fxs->fx_xmm[i], fxs->fx_unused3);
126 for (i = 0; i < nitems(fxs->fx_unused3); i++)
127 printf("unused3[%zu]\t%02x\n", i, fxs->fx_unused3[i]);
128 if (&fxs->fx_unused3[i] != fxs + 1)
129 errx(1, "fx_unused3 end %p, fxsave end %p",
130 &fxs->fx_unused3[i], fxs + 1);
131 }
132