1 /* $FreeBSD$ */ 2 /*- 3 * SPDX-License-Identifier: BSD-2-Clause 4 * 5 * Copyright (c) 2008-2020 Hans Petter Selasky. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #ifdef USB_GLOBAL_INCLUDE_FILE 30 #include USB_GLOBAL_INCLUDE_FILE 31 #else 32 #include <sys/stdint.h> 33 #include <sys/stddef.h> 34 #include <sys/param.h> 35 #include <sys/queue.h> 36 #include <sys/types.h> 37 #include <sys/systm.h> 38 #include <sys/kernel.h> 39 #include <sys/bus.h> 40 #include <sys/module.h> 41 #include <sys/lock.h> 42 #include <sys/mutex.h> 43 #include <sys/condvar.h> 44 #include <sys/sysctl.h> 45 #include <sys/sx.h> 46 #include <sys/unistd.h> 47 #include <sys/callout.h> 48 #include <sys/malloc.h> 49 #include <sys/priv.h> 50 51 #include <dev/usb/usb.h> 52 #include <dev/usb/usbdi.h> 53 #include <dev/usb/usbdi_util.h> 54 55 #define USB_DEBUG_VAR usb_debug 56 57 #include <dev/usb/usb_core.h> 58 #include <dev/usb/usb_debug.h> 59 #endif /* USB_GLOBAL_INCLUDE_FILE */ 60 61 /*------------------------------------------------------------------------* 62 * usb_desc_foreach 63 * 64 * This function is the safe way to iterate across the USB config 65 * descriptor. It contains several checks against invalid 66 * descriptors. If the "desc" argument passed to this function is 67 * "NULL" the first descriptor, if any, will be returned. 68 * 69 * Return values: 70 * NULL: End of descriptors 71 * Else: Next descriptor after "desc" 72 *------------------------------------------------------------------------*/ 73 struct usb_descriptor * 74 usb_desc_foreach(struct usb_config_descriptor *cd, 75 struct usb_descriptor *_desc) 76 { 77 uint8_t *desc_next; 78 uint8_t *start; 79 uint8_t *end; 80 uint8_t *desc; 81 82 /* be NULL safe */ 83 if (cd == NULL) 84 return (NULL); 85 86 /* We assume that the "wTotalLength" has been checked. */ 87 start = (uint8_t *)cd; 88 end = start + UGETW(cd->wTotalLength); 89 desc = (uint8_t *)_desc; 90 91 /* Get start of next USB descriptor. */ 92 if (desc == NULL) 93 desc = start; 94 else 95 desc = desc + desc[0]; 96 97 /* Check that the next USB descriptor is within the range. */ 98 if ((desc < start) || (desc >= end)) 99 return (NULL); /* out of range, or EOD */ 100 101 /* Check that the second next USB descriptor is within range. */ 102 desc_next = desc + desc[0]; 103 if ((desc_next < start) || (desc_next > end)) 104 return (NULL); /* out of range */ 105 106 /* Check minimum descriptor length. */ 107 if (desc[0] < 3) 108 return (NULL); /* too short descriptor */ 109 110 /* Return start of next descriptor. */ 111 return ((struct usb_descriptor *)desc); 112 } 113 114 /*------------------------------------------------------------------------* 115 * usb_idesc_foreach 116 * 117 * This function will iterate the interface descriptors in the config 118 * descriptor. The parse state structure should be zeroed before 119 * calling this function the first time. 120 * 121 * Return values: 122 * NULL: End of descriptors 123 * Else: A valid interface descriptor 124 *------------------------------------------------------------------------*/ 125 struct usb_interface_descriptor * 126 usb_idesc_foreach(struct usb_config_descriptor *cd, 127 struct usb_idesc_parse_state *ps) 128 { 129 struct usb_interface_descriptor *id; 130 uint8_t new_iface; 131 132 /* retrieve current descriptor */ 133 id = (struct usb_interface_descriptor *)ps->desc; 134 /* default is to start a new interface */ 135 new_iface = 1; 136 137 while (1) { 138 id = (struct usb_interface_descriptor *) 139 usb_desc_foreach(cd, (struct usb_descriptor *)id); 140 if (id == NULL) 141 break; 142 if ((id->bDescriptorType == UDESC_INTERFACE) && 143 (id->bLength >= sizeof(*id))) { 144 if (ps->iface_no_last == id->bInterfaceNumber) { 145 /* 146 * Don't allow more than 256 alternate 147 * settings to avoid overflowing the 148 * alternate index which is a 8-bit 149 * variable. 150 */ 151 if (ps->iface_index_alt == 255) { 152 DPRINTF("Interface(%u) has more than 256 alternate settings\n", 153 id->bInterfaceNumber); 154 continue; 155 } 156 new_iface = 0; 157 } 158 ps->iface_no_last = id->bInterfaceNumber; 159 break; 160 } 161 } 162 163 if (ps->desc == NULL) { 164 /* first time or zero descriptors */ 165 } else if (new_iface) { 166 /* new interface */ 167 ps->iface_index ++; 168 ps->iface_index_alt = 0; 169 } else { 170 /* new alternate interface */ 171 ps->iface_index_alt ++; 172 } 173 #if (USB_IFACE_MAX <= 0) 174 #error "USB_IFACE_MAX must be defined greater than zero" 175 #endif 176 /* check for too many interfaces */ 177 if (ps->iface_index >= USB_IFACE_MAX) { 178 DPRINTF("Interface limit reached\n"); 179 id = NULL; 180 } 181 182 /* store and return current descriptor */ 183 ps->desc = (struct usb_descriptor *)id; 184 return (id); 185 } 186 187 /*------------------------------------------------------------------------* 188 * usb_edesc_foreach 189 * 190 * This function will iterate all the endpoint descriptors within an 191 * interface descriptor. Starting value for the "ped" argument should 192 * be a valid interface descriptor. 193 * 194 * Return values: 195 * NULL: End of descriptors 196 * Else: A valid endpoint descriptor 197 *------------------------------------------------------------------------*/ 198 struct usb_endpoint_descriptor * 199 usb_edesc_foreach(struct usb_config_descriptor *cd, 200 struct usb_endpoint_descriptor *ped) 201 { 202 struct usb_descriptor *desc; 203 204 desc = ((struct usb_descriptor *)ped); 205 206 while ((desc = usb_desc_foreach(cd, desc))) { 207 if (desc->bDescriptorType == UDESC_INTERFACE) { 208 break; 209 } 210 if (desc->bDescriptorType == UDESC_ENDPOINT) { 211 if (desc->bLength < sizeof(*ped)) { 212 /* endpoint descriptor is invalid */ 213 break; 214 } 215 return ((struct usb_endpoint_descriptor *)desc); 216 } 217 } 218 return (NULL); 219 } 220 221 /*------------------------------------------------------------------------* 222 * usb_ed_comp_foreach 223 * 224 * This function will iterate all the endpoint companion descriptors 225 * within an endpoint descriptor in an interface descriptor. Starting 226 * value for the "ped" argument should be a valid endpoint companion 227 * descriptor. 228 * 229 * Return values: 230 * NULL: End of descriptors 231 * Else: A valid endpoint companion descriptor 232 *------------------------------------------------------------------------*/ 233 struct usb_endpoint_ss_comp_descriptor * 234 usb_ed_comp_foreach(struct usb_config_descriptor *cd, 235 struct usb_endpoint_ss_comp_descriptor *ped) 236 { 237 struct usb_descriptor *desc; 238 239 desc = ((struct usb_descriptor *)ped); 240 241 while ((desc = usb_desc_foreach(cd, desc))) { 242 if (desc->bDescriptorType == UDESC_INTERFACE) 243 break; 244 if (desc->bDescriptorType == UDESC_ENDPOINT) 245 break; 246 if (desc->bDescriptorType == UDESC_ENDPOINT_SS_COMP) { 247 if (desc->bLength < sizeof(*ped)) { 248 /* endpoint companion descriptor is invalid */ 249 break; 250 } 251 return ((struct usb_endpoint_ss_comp_descriptor *)desc); 252 } 253 } 254 return (NULL); 255 } 256 257 /*------------------------------------------------------------------------* 258 * usbd_get_no_descriptors 259 * 260 * This function will count the total number of descriptors in the 261 * configuration descriptor of type "type". 262 *------------------------------------------------------------------------*/ 263 uint8_t 264 usbd_get_no_descriptors(struct usb_config_descriptor *cd, uint8_t type) 265 { 266 struct usb_descriptor *desc = NULL; 267 uint8_t count = 0; 268 269 while ((desc = usb_desc_foreach(cd, desc))) { 270 if (desc->bDescriptorType == type) { 271 count++; 272 if (count == 0xFF) 273 break; /* crazy */ 274 } 275 } 276 return (count); 277 } 278 279 /*------------------------------------------------------------------------* 280 * usbd_get_no_alts 281 * 282 * Return value: 283 * Number of alternate settings for the given interface descriptor 284 * pointer. If the USB descriptor is corrupt, the returned value can 285 * be greater than the actual number of alternate settings. 286 *------------------------------------------------------------------------*/ 287 uint8_t 288 usbd_get_no_alts(struct usb_config_descriptor *cd, 289 struct usb_interface_descriptor *id) 290 { 291 struct usb_descriptor *desc; 292 uint8_t n; 293 uint8_t ifaceno; 294 295 /* Reset interface count */ 296 297 n = 0; 298 299 /* Get the interface number */ 300 301 ifaceno = id->bInterfaceNumber; 302 303 /* Iterate all the USB descriptors */ 304 305 desc = NULL; 306 while ((desc = usb_desc_foreach(cd, desc))) { 307 if ((desc->bDescriptorType == UDESC_INTERFACE) && 308 (desc->bLength >= sizeof(*id))) { 309 id = (struct usb_interface_descriptor *)desc; 310 if (id->bInterfaceNumber == ifaceno) { 311 n++; 312 if (n == 0xFF) 313 break; /* crazy */ 314 } 315 } 316 } 317 return (n); 318 } 319