1 /* $FreeBSD$ */ 2 /*- 3 * Copyright (c) 2008 Hans Petter Selasky. 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 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #ifdef USB_GLOBAL_INCLUDE_FILE 28 #include USB_GLOBAL_INCLUDE_FILE 29 #else 30 #include <sys/stdint.h> 31 #include <sys/stddef.h> 32 #include <sys/param.h> 33 #include <sys/queue.h> 34 #include <sys/types.h> 35 #include <sys/systm.h> 36 #include <sys/kernel.h> 37 #include <sys/bus.h> 38 #include <sys/module.h> 39 #include <sys/lock.h> 40 #include <sys/mutex.h> 41 #include <sys/condvar.h> 42 #include <sys/sysctl.h> 43 #include <sys/sx.h> 44 #include <sys/unistd.h> 45 #include <sys/callout.h> 46 #include <sys/malloc.h> 47 #include <sys/priv.h> 48 49 #include <dev/usb/usb.h> 50 #include <dev/usb/usbdi.h> 51 #include <dev/usb/usbdi_util.h> 52 #endif /* USB_GLOBAL_INCLUDE_FILE */ 53 54 /*------------------------------------------------------------------------* 55 * usb_desc_foreach 56 * 57 * This function is the safe way to iterate across the USB config 58 * descriptor. It contains several checks against invalid 59 * descriptors. If the "desc" argument passed to this function is 60 * "NULL" the first descriptor, if any, will be returned. 61 * 62 * Return values: 63 * NULL: End of descriptors 64 * Else: Next descriptor after "desc" 65 *------------------------------------------------------------------------*/ 66 struct usb_descriptor * 67 usb_desc_foreach(struct usb_config_descriptor *cd, 68 struct usb_descriptor *_desc) 69 { 70 uint8_t *desc_next; 71 uint8_t *start; 72 uint8_t *end; 73 uint8_t *desc; 74 75 /* be NULL safe */ 76 if (cd == NULL) 77 return (NULL); 78 79 /* We assume that the "wTotalLength" has been checked. */ 80 start = (uint8_t *)cd; 81 end = start + UGETW(cd->wTotalLength); 82 desc = (uint8_t *)_desc; 83 84 /* Get start of next USB descriptor. */ 85 if (desc == NULL) 86 desc = start; 87 else 88 desc = desc + desc[0]; 89 90 /* Check that the next USB descriptor is within the range. */ 91 if ((desc < start) || (desc >= end)) 92 return (NULL); /* out of range, or EOD */ 93 94 /* Check that the second next USB descriptor is within range. */ 95 desc_next = desc + desc[0]; 96 if ((desc_next < start) || (desc_next > end)) 97 return (NULL); /* out of range */ 98 99 /* Check minimum descriptor length. */ 100 if (desc[0] < 3) 101 return (NULL); /* too short descriptor */ 102 103 /* Return start of next descriptor. */ 104 return ((struct usb_descriptor *)desc); 105 } 106 107 /*------------------------------------------------------------------------* 108 * usb_idesc_foreach 109 * 110 * This function will iterate the interface descriptors in the config 111 * descriptor. The parse state structure should be zeroed before 112 * calling this function the first time. 113 * 114 * Return values: 115 * NULL: End of descriptors 116 * Else: A valid interface descriptor 117 *------------------------------------------------------------------------*/ 118 struct usb_interface_descriptor * 119 usb_idesc_foreach(struct usb_config_descriptor *cd, 120 struct usb_idesc_parse_state *ps) 121 { 122 struct usb_interface_descriptor *id; 123 uint8_t new_iface; 124 125 /* retrieve current descriptor */ 126 id = (struct usb_interface_descriptor *)ps->desc; 127 /* default is to start a new interface */ 128 new_iface = 1; 129 130 while (1) { 131 id = (struct usb_interface_descriptor *) 132 usb_desc_foreach(cd, (struct usb_descriptor *)id); 133 if (id == NULL) 134 break; 135 if ((id->bDescriptorType == UDESC_INTERFACE) && 136 (id->bLength >= sizeof(*id))) { 137 if (ps->iface_no_last == id->bInterfaceNumber) 138 new_iface = 0; 139 ps->iface_no_last = id->bInterfaceNumber; 140 break; 141 } 142 } 143 144 if (ps->desc == NULL) { 145 /* first time */ 146 } else if (new_iface) { 147 /* new interface */ 148 ps->iface_index ++; 149 ps->iface_index_alt = 0; 150 } else { 151 /* new alternate interface */ 152 ps->iface_index_alt ++; 153 } 154 155 /* store and return current descriptor */ 156 ps->desc = (struct usb_descriptor *)id; 157 return (id); 158 } 159 160 /*------------------------------------------------------------------------* 161 * usb_edesc_foreach 162 * 163 * This function will iterate all the endpoint descriptors within an 164 * interface descriptor. Starting value for the "ped" argument should 165 * be a valid interface descriptor. 166 * 167 * Return values: 168 * NULL: End of descriptors 169 * Else: A valid endpoint descriptor 170 *------------------------------------------------------------------------*/ 171 struct usb_endpoint_descriptor * 172 usb_edesc_foreach(struct usb_config_descriptor *cd, 173 struct usb_endpoint_descriptor *ped) 174 { 175 struct usb_descriptor *desc; 176 177 desc = ((struct usb_descriptor *)ped); 178 179 while ((desc = usb_desc_foreach(cd, desc))) { 180 if (desc->bDescriptorType == UDESC_INTERFACE) { 181 break; 182 } 183 if (desc->bDescriptorType == UDESC_ENDPOINT) { 184 if (desc->bLength < sizeof(*ped)) { 185 /* endpoint descriptor is invalid */ 186 break; 187 } 188 return ((struct usb_endpoint_descriptor *)desc); 189 } 190 } 191 return (NULL); 192 } 193 194 /*------------------------------------------------------------------------* 195 * usb_ed_comp_foreach 196 * 197 * This function will iterate all the endpoint companion descriptors 198 * within an endpoint descriptor in an interface descriptor. Starting 199 * value for the "ped" argument should be a valid endpoint companion 200 * descriptor. 201 * 202 * Return values: 203 * NULL: End of descriptors 204 * Else: A valid endpoint companion descriptor 205 *------------------------------------------------------------------------*/ 206 struct usb_endpoint_ss_comp_descriptor * 207 usb_ed_comp_foreach(struct usb_config_descriptor *cd, 208 struct usb_endpoint_ss_comp_descriptor *ped) 209 { 210 struct usb_descriptor *desc; 211 212 desc = ((struct usb_descriptor *)ped); 213 214 while ((desc = usb_desc_foreach(cd, desc))) { 215 if (desc->bDescriptorType == UDESC_INTERFACE) 216 break; 217 if (desc->bDescriptorType == UDESC_ENDPOINT) 218 break; 219 if (desc->bDescriptorType == UDESC_ENDPOINT_SS_COMP) { 220 if (desc->bLength < sizeof(*ped)) { 221 /* endpoint companion descriptor is invalid */ 222 break; 223 } 224 return ((struct usb_endpoint_ss_comp_descriptor *)desc); 225 } 226 } 227 return (NULL); 228 } 229 230 /*------------------------------------------------------------------------* 231 * usbd_get_no_descriptors 232 * 233 * This function will count the total number of descriptors in the 234 * configuration descriptor of type "type". 235 *------------------------------------------------------------------------*/ 236 uint8_t 237 usbd_get_no_descriptors(struct usb_config_descriptor *cd, uint8_t type) 238 { 239 struct usb_descriptor *desc = NULL; 240 uint8_t count = 0; 241 242 while ((desc = usb_desc_foreach(cd, desc))) { 243 if (desc->bDescriptorType == type) { 244 count++; 245 if (count == 0xFF) 246 break; /* crazy */ 247 } 248 } 249 return (count); 250 } 251 252 /*------------------------------------------------------------------------* 253 * usbd_get_no_alts 254 * 255 * Return value: 256 * Number of alternate settings for the given interface descriptor 257 * pointer. If the USB descriptor is corrupt, the returned value can 258 * be greater than the actual number of alternate settings. 259 *------------------------------------------------------------------------*/ 260 uint8_t 261 usbd_get_no_alts(struct usb_config_descriptor *cd, 262 struct usb_interface_descriptor *id) 263 { 264 struct usb_descriptor *desc; 265 uint8_t n; 266 uint8_t ifaceno; 267 268 /* Reset interface count */ 269 270 n = 0; 271 272 /* Get the interface number */ 273 274 ifaceno = id->bInterfaceNumber; 275 276 /* Iterate all the USB descriptors */ 277 278 desc = NULL; 279 while ((desc = usb_desc_foreach(cd, desc))) { 280 if ((desc->bDescriptorType == UDESC_INTERFACE) && 281 (desc->bLength >= sizeof(*id))) { 282 id = (struct usb_interface_descriptor *)desc; 283 if (id->bInterfaceNumber == ifaceno) { 284 n++; 285 if (n == 0xFF) 286 break; /* crazy */ 287 } 288 } 289 } 290 return (n); 291 } 292