net/khttpd/rfc.c

   1 /*
   2
   3 kHTTPd -- the next generation
   4
   5 RFC related functions (headers and stuff)
   6
   7 */
   8
   9 /****************************************************************
  10  *      This program is free software; you can redistribute it and/or modify
  11  *      it under the terms of the GNU General Public License as published by
  12  *      the Free Software Foundation; either version 2, or (at your option)
  13  *      any later version.
  14  *
  15  *      This program is distributed in the hope that it will be useful,
  16  *      but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  *      GNU General Public License for more details.
  19  *
  20  *      You should have received a copy of the GNU General Public License
  21  *      along with this program; if not, write to the Free Software
  22  *      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  23  *
  24  ****************************************************************/
  25
  26
  27 #include <linux/kernel.h>
  28
  29 #include <linux/ctype.h>
  30 #include <linux/errno.h>
  31 #include <linux/slab.h>
  32 #include <linux/net.h>
  33 #include <linux/sched.h>
  34 #include <linux/skbuff.h>
  35 #include <linux/unistd.h>
  36 #include <linux/file.h>
  37 #include <linux/smp_lock.h>
  38
  39 #include <net/ip.h>
  40 #include <net/sock.h>
  41
  42 #include <asm/atomic.h>
  43 #include <asm/semaphore.h>
  44 #include <asm/processor.h>
  45 #include <asm/uaccess.h>
  46
  47
  48 #include "prototypes.h"
  49 #include "structure.h"
  50 #include "sysctl.h"
  51
  52
  53 #define KHTTPD_NUMMIMETYPES     40
  54
  55 static atomic_t MimeCount;
  56
  57 struct MimeType
  58 {
  59         __u32   identifier;
  60         char    type[64-sizeof(__u32)-sizeof(__kernel_size_t)];
  61         __kernel_size_t len;
  62 };
  63
  64 static struct MimeType  MimeTypes[KHTTPD_NUMMIMETYPES];
  65
  66
  67 void AddMimeType(const char *Ident,const char *Type)
  68 {
  69         __u32   *I;
  70
  71         EnterFunction("AddMimeType");
  72
  73         if (strlen(Ident)!=4)
  74         {
  75                 (void)printk(KERN_ERR "httpd: Only 4-byte mime-identifiers are accepted\n");
  76                 return;
  77         }
  78
  79         if (strlen(Type)>(64-sizeof(__u32)-sizeof(__kernel_size_t) ) )
  80         {
  81                 (void)printk(KERN_ERR "httpd: Mime-string too long.\n");
  82                 return;
  83         }
  84
  85         I=(__u32*)Ident;
  86
  87         /* FIXME: Need to lock-down all access to the mime-structure here */
  88         /*        For now, just don't add mime-types after initialisation */
  89
  90
  91         MimeTypes[atomic_read(&MimeCount)].identifier=*I;
  92         strncpy(MimeTypes[atomic_read(&MimeCount)].type,Type,(64-sizeof(__u32)-sizeof(__kernel_size_t)));
  93         MimeTypes[atomic_read(&MimeCount)].len = strlen(Type);
  94
  95         atomic_inc(&MimeCount);
  96         LeaveFunction("AddMimeType");
  97 }
  98
  99
 100 char *ResolveMimeType(const char *File,__kernel_size_t *Len)
 101 /*
 102
 103         The returned string is for READ ONLY, ownership of the memory is NOT
 104         transferred.
 105
 106 */
 107 {
 108         __u32   *I;
 109         int pos,lc,filelen;
 110
 111         EnterFunction("ResolveMimeType");
 112
 113         *Len = 0;
 114
 115         if (File==NULL)
 116                 return NULL;
 117
 118         filelen = (int)strlen(File);
 119
 120         if (filelen<4)
 121         {
 122                 return NULL;
 123         }
 124
 125         /* The Merced-people are NOT going to like this! So this has to be fixed
 126            in a later stage. */
 127
 128         pos = filelen-4;
 129         I=(__u32*)(File+pos);
 130
 131         lc=0;
 132
 133         while (lc<atomic_read(&MimeCount))
 134         {
 135                 if (MimeTypes[lc].identifier == *I)
 136                 {
 137                         *Len = MimeTypes[lc].len;
 138                         LeaveFunction("ResolveMimeType - success");
 139                         return MimeTypes[lc].type;
 140                 }
 141                 lc++;
 142         }
 143
 144         if (sysctl_khttpd_sloppymime)
 145         {
 146                 *Len = MimeTypes[0].len;
 147                 LeaveFunction("ResolveMimeType - unknown");
 148                 return MimeTypes[0].type;
 149         }
 150         else
 151         {
 152                 LeaveFunction("ResolveMimeType - failure");
 153                 return NULL;
 154         }
 155 }
 156
 157
 158 static char HeaderPart1[] = "HTTP/1.0 200 OK\r\nServer: kHTTPd/0.1.6\r\nDate: ";
 159 #ifdef BENCHMARK
 160 static char HeaderPart1b[] ="HTTP/1.0 200 OK";
 161 #endif
 162 static char HeaderPart3[] = "\r\nContent-type: ";
 163 static char HeaderPart5[] = "\r\nLast-modified: ";
 164 static char HeaderPart7[] = "\r\nContent-length: ";
 165 static char HeaderPart9[] = "\r\n\r\n";
 166
 167 #ifdef BENCHMARK
 168 /* In BENCHMARK-mode, just send the bare essentials */
 169 void SendHTTPHeader(struct http_request *Request)
 170 {
 171         struct msghdr   msg;
 172         mm_segment_t    oldfs;
 173         struct iovec    iov[9];
 174         int             len,len2;
 175
 176
 177         EnterFunction("SendHTTPHeader");
 178
 179         msg.msg_name     = 0;
 180         msg.msg_namelen  = 0;
 181         msg.msg_iov      = &iov[0];
 182         msg.msg_iovlen   = 6;
 183         msg.msg_control  = NULL;
 184         msg.msg_controllen = 0;
 185         msg.msg_flags    = 0;  /* Synchronous for now */
 186
 187         iov[0].iov_base = HeaderPart1b;
 188         iov[0].iov_len  = 15;
 189         iov[1].iov_base = HeaderPart3;
 190         iov[1].iov_len  = 16;
 191         iov[2].iov_base = Request->MimeType;
 192         iov[2].iov_len  = Request->MimeLength;
 193
 194         iov[3].iov_base = HeaderPart7;
 195         iov[3].iov_len  = 18;
 196
 197
 198         sprintf(Request->LengthS,"%i",Request->FileLength);
 199         iov[4].iov_base = Request->LengthS;
 200         iov[4].iov_len  = strlen(Request->LengthS);
 201         iov[5].iov_base = HeaderPart9;
 202         iov[5].iov_len  = 4;
 203
 204         len2=15+16+18+iov[2].iov_len+iov[4].iov_len+4;
 205
 206
 207         len = 0;
 208
 209
 210         oldfs = get_fs(); set_fs(KERNEL_DS);
 211         len = sock_sendmsg(Request->sock,&msg,len2);
 212         set_fs(oldfs);
 213
 214
 215         return;
 216 }
 217 #else
 218 void SendHTTPHeader(struct http_request *Request)
 219 {
 220         struct msghdr   msg;
 221         mm_segment_t    oldfs;
 222         struct iovec    iov[9];
 223         int             len,len2;
 224         __kernel_size_t slen;
 225
 226         EnterFunction("SendHTTPHeader");
 227
 228         msg.msg_name     = 0;
 229         msg.msg_namelen  = 0;
 230         msg.msg_iov      = &(iov[0]);
 231         msg.msg_iovlen   = 9;
 232         msg.msg_control  = NULL;
 233         msg.msg_controllen = 0;
 234         msg.msg_flags    = 0;  /* Synchronous for now */
 235
 236         iov[0].iov_base = HeaderPart1;
 237         iov[0].iov_len  = 45;
 238         iov[1].iov_base = CurrentTime;
 239         iov[1].iov_len  = 29;
 240         iov[2].iov_base = HeaderPart3;
 241         iov[2].iov_len  = 16;
 242
 243         iov[3].iov_base = Request->MimeType;
 244         iov[3].iov_len  = Request->MimeLength;
 245
 246         iov[4].iov_base = HeaderPart5;
 247         iov[4].iov_len  = 17;
 248         iov[5].iov_base = &(Request->TimeS[0]);
 249         iov[5].iov_len  = 29;
 250         iov[6].iov_base = HeaderPart7;
 251         iov[6].iov_len  = 18;
 252         iov[7].iov_base = &(Request->LengthS[0]);
 253         slen = strlen(Request->LengthS);
 254         iov[7].iov_len  = slen;
 255         iov[8].iov_base = HeaderPart9;
 256         iov[8].iov_len  = 4;
 257
 258         len2=45+2*29+16+17+18+slen+4+iov[3].iov_len;
 259
 260         len = 0;
 261
 262         oldfs = get_fs(); set_fs(KERNEL_DS);
 263         len = sock_sendmsg(Request->sock,&msg,len2);
 264         set_fs(oldfs);
 265         LeaveFunction("SendHTTPHeader");
 266
 267
 268         return;
 269 }
 270 #endif
 271
 272
 273
 274 /*
 275
 276 Parse a HTTP-header. Be careful for buffer-overflows here, this is the most important
 277 place for this, since the remote-user controls the data.
 278
 279 */
 280 void ParseHeader(char *Buffer,const int length, struct http_request *Head)
 281 {
 282         char *Endval,*EOL,*tmp;
 283
 284         EnterFunction("ParseHeader");
 285         Endval = Buffer + length;
 286
 287         /* We want to parse only the first header if multiple headers are present */
 288         tmp = strstr(Buffer,"\r\n\r\n");
 289         if (tmp!=NULL)
 290             Endval = tmp;
 291
 292
 293         while (Buffer<Endval)
 294         {
 295                 if (isspace(Buffer[0]))
 296                 {
 297                         Buffer++;
 298                         continue;
 299                 }
 300
 301
 302                 EOL=strchr(Buffer,'\n');
 303
 304                 if (EOL==NULL) EOL=Endval;
 305
 306                 if (EOL-Buffer<4)
 307                 {
 308                         Buffer++;
 309                         continue;
 310                 }
 311
 312                 if (strncmp("GET ",Buffer,4)==0)
 313                 {
 314                         int PrefixLen;
 315                         Buffer+=4;
 316
 317                         tmp=strchr(Buffer,' ');
 318                         if (tmp==0)
 319                         {
 320                                 tmp=EOL-1;
 321                                 Head->HTTPVER = 9;
 322                         } else
 323                                 Head->HTTPVER = 10;
 324
 325                         if (tmp>Endval) continue;
 326
 327                         strncpy(Head->FileName,sysctl_khttpd_docroot,sizeof(Head->FileName));
 328                         PrefixLen = strlen(sysctl_khttpd_docroot);
 329                         Head->FileNameLength = min_t(unsigned int, 255, tmp - Buffer + PrefixLen);
 330
 331                         strncat(Head->FileName,Buffer,min_t(unsigned int, 255 - PrefixLen, tmp - Buffer));
 332
 333                         Buffer=EOL+1;
 334 #ifdef BENCHMARK
 335                         break;
 336 #endif
 337                         continue;
 338                 }
 339 #ifndef BENCHMARK
 340                 if (strncmp("If-Modified-Since: ",Buffer,19)==0)
 341                 {
 342                         Buffer+=19;
 343
 344                         strncpy(Head->IMS,Buffer,min_t(unsigned int, 127,EOL-Buffer-1));
 345
 346                         Buffer=EOL+1;
 347                         continue;
 348                 }
 349
 350                 if (strncmp("User-Agent: ",Buffer,12)==0)
 351                 {
 352                         Buffer+=12;
 353
 354                         strncpy(Head->Agent,Buffer,min_t(unsigned int, 127,EOL-Buffer-1));
 355
 356                         Buffer=EOL+1;
 357                         continue;
 358                 }
 359
 360
 361                 if (strncmp("Host: ",Buffer,6)==0)
 362                 {
 363                         Buffer+=6;
 364
 365                         strncpy(Head->Host,Buffer,min_t(unsigned int, 127,EOL-Buffer-1));
 366
 367                         Buffer=EOL+1;
 368                         continue;
 369                 }
 370 #endif
 371                 Buffer = EOL+1;  /* Skip line */
 372         }
 373         LeaveFunction("ParseHeader");
 374 }