xref: /aosp_15_r20/external/pciutils/lib/filter.c (revision c2e0c6b56a71da9abe8df5c8348fb3eb5c2c9251)
1 /*
2  *	The PCI Library -- Device Filtering
3  *
4  *	Copyright (c) 1998--2022 Martin Mares <[email protected]>
5  *
6  *	Can be freely distributed and used under the terms of the GNU GPL v2+.
7  *
8  *	SPDX-License-Identifier: GPL-2.0-or-later
9  */
10 
11 #include <stdlib.h>
12 #include <string.h>
13 
14 #include "internal.h"
15 
16 void pci_filter_init_v38(struct pci_access *a UNUSED, struct pci_filter *f) VERSIONED_ABI;
17 char *pci_filter_parse_slot_v38(struct pci_filter *f, char *str) VERSIONED_ABI;
18 char *pci_filter_parse_id_v38(struct pci_filter *f, char *str) VERSIONED_ABI;
19 int pci_filter_match_v38(struct pci_filter *f, struct pci_dev *d) VERSIONED_ABI;
20 
21 void
pci_filter_init_v38(struct pci_access * a UNUSED,struct pci_filter * f)22 pci_filter_init_v38(struct pci_access *a UNUSED, struct pci_filter *f)
23 {
24   memset((byte *) f, 0, sizeof(*f));
25   f->domain = f->bus = f->slot = f->func = -1;
26   f->vendor = f->device = -1;
27   f->device_class = -1;
28   f->device_class_mask = ~0U;
29   f->prog_if = -1;
30 }
31 
32 #define BUF_SIZE 64
33 
34 static char *
split_to_fields(char * str,char * buffer,int sep,char ** fields,int num_fields)35 split_to_fields(char *str, char *buffer, int sep, char **fields, int num_fields)
36 {
37   if (buffer)
38     {
39       if (strlen(str) >= BUF_SIZE)
40 	return "Expression too long";
41       strcpy(buffer, str);
42       str = buffer;
43     }
44 
45   int i = 0;
46 
47   for (;;)
48     {
49       if (i >= num_fields)
50 	return "Too many fields";
51       fields[i++] = str;
52       while (*str && *str != sep)
53 	str++;
54       if (!*str)
55 	break;
56       *str++ = 0;
57     }
58 
59   while (i < num_fields)
60     fields[i++] = NULL;
61 
62   return NULL;
63 }
64 
65 static int
field_defined(char * field)66 field_defined(char *field)
67 {
68   return field && field[0] && strcmp(field, "*");
69 }
70 
71 static int
parse_hex_field(char * str,int * outp,unsigned int * maskp,unsigned int max)72 parse_hex_field(char *str, int *outp, unsigned int *maskp, unsigned int max)
73 {
74   unsigned int out = 0;
75   unsigned int mask = ~0U;
76   unsigned int bound = 0;
77 
78   if (!field_defined(str))
79     return 1;	// and keep the defaults
80 
81   // Historically, filters allowed writing hexadecimal numbers with leading "0x".
82   // This was never intentional nor documented, but some people relied on it.
83   if (!maskp && str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
84     str += 2;
85 
86   while (*str)
87     {
88       int c = *str++;
89       int d;
90 
91       if ((c == 'x' || c == 'X') && maskp)
92 	{
93 	  out = out << 4;
94 	  bound = (bound << 4) | 1;
95 	  mask = mask << 4;
96 	}
97       else
98 	{
99 	  if (c >= '0' && c <= '9')
100 	    d = c - '0';
101 	  else if (c >= 'A' && c <= 'F')
102 	    d = c - 'A' + 10;
103 	  else if (c >= 'a' && c <= 'f')
104 	    d = c - 'a' + 10;
105 	  else
106 	    return 0;
107 
108 	  out = (out << 4) | d;
109 	  bound = (bound << 4) | d;
110 	  mask = (mask << 4) | 0xf;
111 	}
112 
113       if (bound > max)
114 	return 0;
115     }
116 
117   *outp = out;
118   if (maskp)
119     *maskp = mask;
120   return 1;
121 }
122 
123 /* Slot filter syntax: [[[domain]:][bus]:][slot][.[func]] */
124 
125 char *
pci_filter_parse_slot_v38(struct pci_filter * f,char * str)126 pci_filter_parse_slot_v38(struct pci_filter *f, char *str)
127 {
128   char buf[BUF_SIZE];
129   char *fields[3];
130   char *err;
131 
132   if (err = split_to_fields(str, buf, ':', fields, 3))
133     return err;
134 
135   int i = 0;
136   if (fields[2])
137     {
138       if (!parse_hex_field(fields[0], &f->domain, NULL, 0x7fffffff))
139 	return "Invalid domain number";
140       i++;
141     }
142 
143   if (fields[i+1])
144     {
145       if (!parse_hex_field(fields[i], &f->bus, NULL, 0xff))
146 	return "Invalid bus number";
147       i++;
148     }
149 
150   char *fdev = fields[i];
151   if (field_defined(fdev))
152     {
153       char *sfields[2];
154       if (split_to_fields(fdev, NULL, '.', sfields, 2))
155 	return "Invalid slot/function number";
156 
157       if (!parse_hex_field(sfields[0], &f->slot, NULL, 0x1f))
158 	return "Invalid slot number";
159 
160       if (!parse_hex_field(sfields[1], &f->func, NULL, 7))
161 	return "Invalid function number";
162     }
163 
164   return NULL;
165 }
166 
167 /* ID filter syntax: [vendor]:[device][:class[:progif]] */
168 
169 char *
pci_filter_parse_id_v38(struct pci_filter * f,char * str)170 pci_filter_parse_id_v38(struct pci_filter *f, char *str)
171 {
172   char buf[BUF_SIZE];
173   char *fields[4];
174   char *err;
175 
176   if (err = split_to_fields(str, buf, ':', fields, 4))
177     return err;
178 
179   if (!fields[1])
180     return "At least two fields must be given";
181 
182   if (!parse_hex_field(fields[0], &f->vendor, NULL, 0xffff))
183     return "Invalid vendor ID";
184 
185   if (!parse_hex_field(fields[1], &f->device, NULL, 0xffff))
186     return "Invalid device ID";
187 
188   if (!parse_hex_field(fields[2], &f->device_class, &f->device_class_mask, 0xffff))
189     return "Invalid class code";
190 
191   if (!parse_hex_field(fields[3], &f->prog_if, NULL, 0xff))
192     return "Invalid programming interface code";
193 
194   return NULL;
195 }
196 
197 int
pci_filter_match_v38(struct pci_filter * f,struct pci_dev * d)198 pci_filter_match_v38(struct pci_filter *f, struct pci_dev *d)
199 {
200   if ((f->domain >= 0 && f->domain != d->domain) ||
201       (f->bus >= 0 && f->bus != d->bus) ||
202       (f->slot >= 0 && f->slot != d->dev) ||
203       (f->func >= 0 && f->func != d->func))
204     return 0;
205   if (f->device >= 0 || f->vendor >= 0)
206     {
207       pci_fill_info_v313(d, PCI_FILL_IDENT);
208       if ((f->device >= 0 && f->device != d->device_id) ||
209 	  (f->vendor >= 0 && f->vendor != d->vendor_id))
210 	return 0;
211     }
212   if (f->device_class >= 0)
213     {
214       pci_fill_info_v313(d, PCI_FILL_CLASS);
215       if ((f->device_class ^ d->device_class) & f->device_class_mask)
216 	return 0;
217     }
218   if (f->prog_if >= 0)
219     {
220       pci_fill_info_v313(d, PCI_FILL_CLASS_EXT);
221       if (f->prog_if != d->prog_if)
222 	return 0;
223     }
224   return 1;
225 }
226 
227 /*
228  * Before pciutils v3.3, struct pci_filter had fewer fields,
229  * so we have to provide compatibility wrappers.
230  */
231 
232 struct pci_filter_v30 {
233   int domain, bus, slot, func;			/* -1 = ANY */
234   int vendor, device;
235 };
236 
237 void pci_filter_init_v30(struct pci_access *a, struct pci_filter_v30 *f) VERSIONED_ABI;
238 char *pci_filter_parse_slot_v30(struct pci_filter_v30 *f, char *str) VERSIONED_ABI;
239 char *pci_filter_parse_id_v30(struct pci_filter_v30 *f, char *str) VERSIONED_ABI;
240 int pci_filter_match_v30(struct pci_filter_v30 *f, struct pci_dev *d) VERSIONED_ABI;
241 
242 static void
pci_filter_import_v30(struct pci_filter_v30 * old,struct pci_filter * new)243 pci_filter_import_v30(struct pci_filter_v30 *old, struct pci_filter *new)
244 {
245   new->domain = old->domain;
246   new->bus = old->bus;
247   new->slot = old->slot;
248   new->func = old->func;
249   new->vendor = old->vendor;
250   new->device = old->device;
251   new->device_class = -1;
252   new->device_class_mask = ~0U;
253   new->prog_if = -1;
254 }
255 
256 static void
pci_filter_export_v30(struct pci_filter * new,struct pci_filter_v30 * old)257 pci_filter_export_v30(struct pci_filter *new, struct pci_filter_v30 *old)
258 {
259   old->domain = new->domain;
260   old->bus = new->bus;
261   old->slot = new->slot;
262   old->func = new->func;
263   old->vendor = new->vendor;
264   old->device = new->device;
265 }
266 
267 void
pci_filter_init_v30(struct pci_access * a,struct pci_filter_v30 * f)268 pci_filter_init_v30(struct pci_access *a, struct pci_filter_v30 *f)
269 {
270   struct pci_filter new;
271   pci_filter_init_v38(a, &new);
272   pci_filter_export_v30(&new, f);
273 }
274 
275 char *
pci_filter_parse_slot_v30(struct pci_filter_v30 * f,char * str)276 pci_filter_parse_slot_v30(struct pci_filter_v30 *f, char *str)
277 {
278   struct pci_filter new;
279   char *err;
280   pci_filter_import_v30(f, &new);
281   if (err = pci_filter_parse_slot_v38(&new, str))
282     return err;
283   pci_filter_export_v30(&new, f);
284   return NULL;
285 }
286 
287 char *
pci_filter_parse_id_v30(struct pci_filter_v30 * f,char * str)288 pci_filter_parse_id_v30(struct pci_filter_v30 *f, char *str)
289 {
290   struct pci_filter new;
291   char *err;
292   pci_filter_import_v30(f, &new);
293   if (err = pci_filter_parse_id_v38(&new, str))
294     return err;
295   if (new.device_class >= 0 || new.prog_if >= 0)
296     return "Filtering by class or programming interface not supported in this program";
297   pci_filter_export_v30(&new, f);
298   return NULL;
299 }
300 
301 int
pci_filter_match_v30(struct pci_filter_v30 * f,struct pci_dev * d)302 pci_filter_match_v30(struct pci_filter_v30 *f, struct pci_dev *d)
303 {
304   struct pci_filter new;
305   pci_filter_import_v30(f, &new);
306   return pci_filter_match_v38(&new, d);
307 }
308 
309 // Version 3.3 is the same as version 3.8, only device_class_mask and prog_if were not implemented
310 // (their positions in struct pci_filter were declared as RFU).
311 
312 STATIC_ALIAS(void pci_filter_init(struct pci_access *a, struct pci_filter *f), pci_filter_init_v38(a, f));
313 DEFINE_ALIAS(void pci_filter_init_v33(struct pci_access *a, struct pci_filter *f), pci_filter_init_v38);
314 SYMBOL_VERSION(pci_filter_init_v30, pci_filter_init@LIBPCI_3.0);
315 SYMBOL_VERSION(pci_filter_init_v33, pci_filter_init@LIBPCI_3.3);
316 SYMBOL_VERSION(pci_filter_init_v38, pci_filter_init@@LIBPCI_3.8);
317 
318 STATIC_ALIAS(char *pci_filter_parse_slot(struct pci_filter *f, char *str), pci_filter_parse_slot_v38(f, str));
319 DEFINE_ALIAS(char *pci_filter_parse_slot_v33(struct pci_filter *f, char *str), pci_filter_parse_slot_v38);
320 SYMBOL_VERSION(pci_filter_parse_slot_v30, pci_filter_parse_slot@LIBPCI_3.0);
321 SYMBOL_VERSION(pci_filter_parse_slot_v33, pci_filter_parse_slot@LIBPCI_3.3);
322 SYMBOL_VERSION(pci_filter_parse_slot_v38, pci_filter_parse_slot@@LIBPCI_3.8);
323 
324 STATIC_ALIAS(char *pci_filter_parse_id(struct pci_filter *f, char *str), pci_filter_parse_id_v38(f, str));
325 DEFINE_ALIAS(char *pci_filter_parse_id_v33(struct pci_filter *f, char *str), pci_filter_parse_id_v38);
326 SYMBOL_VERSION(pci_filter_parse_id_v30, pci_filter_parse_id@LIBPCI_3.0);
327 SYMBOL_VERSION(pci_filter_parse_id_v33, pci_filter_parse_id@LIBPCI_3.3);
328 SYMBOL_VERSION(pci_filter_parse_id_v38, pci_filter_parse_id@@LIBPCI_3.8);
329 
330 STATIC_ALIAS(int pci_filter_match(struct pci_filter *f, struct pci_dev *d), pci_filter_match_v38(f, d));
331 DEFINE_ALIAS(int pci_filter_match_v33(struct pci_filter *f, struct pci_dev *d), pci_filter_match_v38);
332 SYMBOL_VERSION(pci_filter_match_v30, pci_filter_match@LIBPCI_3.0);
333 SYMBOL_VERSION(pci_filter_match_v33, pci_filter_match@LIBPCI_3.3);
334 SYMBOL_VERSION(pci_filter_match_v38, pci_filter_match@@LIBPCI_3.8);
335