1 /*
2 * Copyright (c) 2015 Dmitry V. Levin <ldv@altlinux.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. The name of the author may not be used to endorse or promote products
14 * derived from this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28 #include "defs.h"
29
30 #ifdef HAVE_LINUX_BPF_H
31 # include <linux/bpf.h>
32 #endif
33
34 #include "xlat/bpf_commands.h"
35 #include "xlat/bpf_map_types.h"
36 #include "xlat/bpf_prog_types.h"
37 #include "xlat/bpf_map_update_elem_flags.h"
38
39 static int
bpf_map_create(struct tcb * tcp,const long addr,unsigned int size)40 bpf_map_create(struct tcb *tcp, const long addr, unsigned int size)
41 {
42 struct {
43 uint32_t map_type, key_size, value_size, max_entries;
44 } attr = {};
45
46 if (!size) {
47 printaddr(addr);
48 return RVAL_DECODED | RVAL_FD;
49 }
50 if (size > sizeof(attr))
51 size = sizeof(attr);
52 if (umoven_or_printaddr(tcp, addr, size, &attr))
53 return RVAL_DECODED | RVAL_FD;
54
55 tprints("{map_type=");
56 printxval(bpf_map_types, attr.map_type, "BPF_MAP_TYPE_???");
57 tprintf(", key_size=%u, value_size=%u, max_entries=%u}",
58 attr.key_size, attr.value_size, attr.max_entries);
59
60 return RVAL_DECODED | RVAL_FD;
61 }
62
63 static void
bpf_map_update_elem(struct tcb * tcp,const long addr,unsigned int size)64 bpf_map_update_elem(struct tcb *tcp, const long addr, unsigned int size)
65 {
66 struct {
67 uint32_t map_fd;
68 uint64_t ATTRIBUTE_ALIGNED(8) key;
69 uint64_t ATTRIBUTE_ALIGNED(8) value;
70 uint64_t flags;
71 } attr = {};
72
73 if (!size) {
74 printaddr(addr);
75 return;
76 }
77 if (size > sizeof(attr))
78 size = sizeof(attr);
79 if (umoven_or_printaddr(tcp, addr, size, &attr))
80 return;
81
82 tprints("{map_fd=");
83 printfd(tcp, attr.map_fd);
84 tprintf(", key=%#" PRIx64 ", value=%#" PRIx64 ", flags=",
85 attr.key, attr.value);
86 printxval(bpf_map_update_elem_flags, attr.flags, "BPF_???");
87 tprints("}");
88 }
89
90 static void
bpf_map_delete_elem(struct tcb * tcp,const long addr,unsigned int size)91 bpf_map_delete_elem(struct tcb *tcp, const long addr, unsigned int size)
92 {
93 struct {
94 uint32_t map_fd;
95 uint64_t ATTRIBUTE_ALIGNED(8) key;
96 } attr = {};
97
98 if (!size) {
99 printaddr(addr);
100 return;
101 }
102 if (size > sizeof(attr))
103 size = sizeof(attr);
104 if (umoven_or_printaddr(tcp, addr, size, &attr))
105 return;
106
107 tprints("{map_fd=");
108 printfd(tcp, attr.map_fd);
109 tprintf(", key=%#" PRIx64 "}", attr.key);
110 }
111
112 static int
bpf_map_io(struct tcb * tcp,const long addr,unsigned int size,const char * text)113 bpf_map_io(struct tcb *tcp, const long addr, unsigned int size, const char *text)
114 {
115 struct bpf_io_elem_struct {
116 uint32_t map_fd;
117 uint64_t ATTRIBUTE_ALIGNED(8) key;
118 uint64_t ATTRIBUTE_ALIGNED(8) value;
119 } attr = {};
120
121 if (exiting(tcp)) {
122 if (!syserror(tcp) && !umove_or_printaddr(tcp, addr, &attr))
123 tprintf(", %s=%#" PRIx64, text, attr.value);
124 tprints("}");
125 return RVAL_DECODED;
126 }
127
128 if (!size) {
129 printaddr(addr);
130 return RVAL_DECODED;
131 }
132 if (size > sizeof(attr))
133 size = sizeof(attr);
134 if (umoven_or_printaddr(tcp, addr, size, &attr))
135 return RVAL_DECODED;
136
137 tprints("{map_fd=");
138 printfd(tcp, attr.map_fd);
139 tprintf(", key=%#" PRIx64, attr.key);
140
141 return 0;
142 }
143
144 static int
bpf_prog_load(struct tcb * tcp,const long addr,unsigned int size)145 bpf_prog_load(struct tcb *tcp, const long addr, unsigned int size)
146 {
147 struct {
148 uint32_t prog_type, insn_cnt;
149 uint64_t ATTRIBUTE_ALIGNED(8) insns, license;
150 uint32_t log_level, log_size;
151 uint64_t ATTRIBUTE_ALIGNED(8) log_buf;
152 uint32_t kern_version;
153 } attr = {};
154
155 if (!size) {
156 printaddr(addr);
157 return RVAL_DECODED | RVAL_FD;
158 }
159 if (size > sizeof(attr))
160 size = sizeof(attr);
161 if (umoven_or_printaddr(tcp, addr, size, &attr))
162 return RVAL_DECODED | RVAL_FD;
163
164 tprints("{prog_type=");
165 printxval(bpf_prog_types, attr.prog_type, "BPF_PROG_TYPE_???");
166 tprintf(", insn_cnt=%u, insns=%#" PRIx64 ", license=",
167 attr.insn_cnt, attr.insns);
168 printstr(tcp, attr.license, -1);
169 tprintf(", log_level=%u, log_size=%u, log_buf=%#" PRIx64 ", kern_version=%u}",
170 attr.log_level, attr.log_size, attr.log_buf, attr.kern_version);
171
172 return RVAL_DECODED | RVAL_FD;
173 }
174
SYS_FUNC(bpf)175 SYS_FUNC(bpf)
176 {
177 const int cmd = tcp->u_arg[0];
178 const long addr = tcp->u_arg[1];
179 const unsigned int size = tcp->u_arg[2];
180 int rc = RVAL_DECODED;
181
182 if (entering(tcp)) {
183 printxval(bpf_commands, cmd, "BPF_???");
184 tprints(", ");
185 }
186
187 switch (cmd) {
188 case BPF_MAP_CREATE:
189 rc = bpf_map_create(tcp, addr, size);
190 break;
191 case BPF_MAP_LOOKUP_ELEM:
192 rc = bpf_map_io(tcp, addr, size, "value");
193 break;
194 case BPF_MAP_UPDATE_ELEM:
195 bpf_map_update_elem(tcp, addr, size);
196 break;
197 case BPF_MAP_DELETE_ELEM:
198 bpf_map_delete_elem(tcp, addr, size);
199 break;
200 case BPF_MAP_GET_NEXT_KEY:
201 rc = bpf_map_io(tcp, addr, size, "next_key");
202 break;
203 case BPF_PROG_LOAD:
204 rc = bpf_prog_load(tcp, addr, size);
205 break;
206 default:
207 printaddr(addr);
208 break;
209 }
210
211 if (rc & RVAL_DECODED)
212 tprintf(", %u", size);
213
214 return rc;
215 }
216