1 /* $FreeBSD$ */ 2 /*- 3 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 4 * 5 * Copyright (c) 2008 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 new_iface = 0; 146 ps->iface_no_last = id->bInterfaceNumber; 147 break; 148 } 149 } 150 151 if (ps->desc == NULL) { 152 /* first time or zero descriptors */ 153 } else if (new_iface) { 154 /* new interface */ 155 ps->iface_index ++; 156 ps->iface_index_alt = 0; 157 } else { 158 /* new alternate interface */ 159 ps->iface_index_alt ++; 160 } 161 #if (USB_IFACE_MAX <= 0) 162 #error "USB_IFACE_MAX must be defined greater than zero" 163 #endif 164 /* check for too many interfaces */ 165 if (ps->iface_index >= USB_IFACE_MAX) { 166 DPRINTF("Interface limit reached\n"); 167 id = NULL; 168 } 169 170 /* store and return current descriptor */ 171 ps->desc = (struct usb_descriptor *)id; 172 return (id); 173 } 174 175 /*------------------------------------------------------------------------* 176 * usb_edesc_foreach 177 * 178 * This function will iterate all the endpoint descriptors within an 179 * interface descriptor. Starting value for the "ped" argument should 180 * be a valid interface descriptor. 181 * 182 * Return values: 183 * NULL: End of descriptors 184 * Else: A valid endpoint descriptor 185 *------------------------------------------------------------------------*/ 186 struct usb_endpoint_descriptor * 187 usb_edesc_foreach(struct usb_config_descriptor *cd, 188 struct usb_endpoint_descriptor *ped) 189 { 190 struct usb_descriptor *desc; 191 192 desc = ((struct usb_descriptor *)ped); 193 194 while ((desc = usb_desc_foreach(cd, desc))) { 195 if (desc->bDescriptorType == UDESC_INTERFACE) { 196 break; 197 } 198 if (desc->bDescriptorType == UDESC_ENDPOINT) { 199 if (desc->bLength < sizeof(*ped)) { 200 /* endpoint descriptor is invalid */ 201 break; 202 } 203 return ((struct usb_endpoint_descriptor *)desc); 204 } 205 } 206 return (NULL); 207 } 208 209 /*------------------------------------------------------------------------* 210 * usb_ed_comp_foreach 211 * 212 * This function will iterate all the endpoint companion descriptors 213 * within an endpoint descriptor in an interface descriptor. Starting 214 * value for the "ped" argument should be a valid endpoint companion 215 * descriptor. 216 * 217 * Return values: 218 * NULL: End of descriptors 219 * Else: A valid endpoint companion descriptor 220 *------------------------------------------------------------------------*/ 221 struct usb_endpoint_ss_comp_descriptor * 222 usb_ed_comp_foreach(struct usb_config_descriptor *cd, 223 struct usb_endpoint_ss_comp_descriptor *ped) 224 { 225 struct usb_descriptor *desc; 226 227 desc = ((struct usb_descriptor *)ped); 228 229 while ((desc = usb_desc_foreach(cd, desc))) { 230 if (desc->bDescriptorType == UDESC_INTERFACE) 231 break; 232 if (desc->bDescriptorType == UDESC_ENDPOINT) 233 break; 234 if (desc->bDescriptorType == UDESC_ENDPOINT_SS_COMP) { 235 if (desc->bLength < sizeof(*ped)) { 236 /* endpoint companion descriptor is invalid */ 237 break; 238 } 239 return ((struct usb_endpoint_ss_comp_descriptor *)desc); 240 } 241 } 242 return (NULL); 243 } 244 245 /*------------------------------------------------------------------------* 246 * usbd_get_no_descriptors 247 * 248 * This function will count the total number of descriptors in the 249 * configuration descriptor of type "type". 250 *------------------------------------------------------------------------*/ 251 uint8_t 252 usbd_get_no_descriptors(struct usb_config_descriptor *cd, uint8_t type) 253 { 254 struct usb_descriptor *desc = NULL; 255 uint8_t count = 0; 256 257 while ((desc = usb_desc_foreach(cd, desc))) { 258 if (desc->bDescriptorType == type) { 259 count++; 260 if (count == 0xFF) 261 break; /* crazy */ 262 } 263 } 264 return (count); 265 } 266 267 /*------------------------------------------------------------------------* 268 * usbd_get_no_alts 269 * 270 * Return value: 271 * Number of alternate settings for the given interface descriptor 272 * pointer. If the USB descriptor is corrupt, the returned value can 273 * be greater than the actual number of alternate settings. 274 *------------------------------------------------------------------------*/ 275 uint8_t 276 usbd_get_no_alts(struct usb_config_descriptor *cd, 277 struct usb_interface_descriptor *id) 278 { 279 struct usb_descriptor *desc; 280 uint8_t n; 281 uint8_t ifaceno; 282 283 /* Reset interface count */ 284 285 n = 0; 286 287 /* Get the interface number */ 288 289 ifaceno = id->bInterfaceNumber; 290 291 /* Iterate all the USB descriptors */ 292 293 desc = NULL; 294 while ((desc = usb_desc_foreach(cd, desc))) { 295 if ((desc->bDescriptorType == UDESC_INTERFACE) && 296 (desc->bLength >= sizeof(*id))) { 297 id = (struct usb_interface_descriptor *)desc; 298 if (id->bInterfaceNumber == ifaceno) { 299 n++; 300 if (n == 0xFF) 301 break; /* crazy */ 302 } 303 } 304 } 305 return (n); 306 } 307