NetDisk/http.c
Stephen Heumann 65c6c68936 HTTP header parsing tweaks.
These should slightly improve performance.
2018-10-08 21:18:32 -05:00

436 lines
12 KiB
C

#pragma lint -1
#pragma noroot
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <types.h>
#include <tcpip.h>
#include <misctool.h>
#include <memory.h>
#include <orca.h>
#include <errno.h>
#include "session.h"
#include "http.h"
#include "tcpconnection.h"
#include "strcasecmp.h"
#include "seturl.h"
#include "version.h"
#define buffTypePointer 0x0000 /* For TCPIPReadTCP() */
#define buffTypeHandle 0x0001
#define buffTypeNewHandle 0x0002
#define HTTP_RESPONSE_TIMEOUT 15 /* seconds to wait for response headers */
#define MAX_REDIRECTS 5
enum ResponseHeader {
UNKNOWN_HEADER = 0,
CONTENT_RANGE,
CONTENT_LENGTH,
TRANSFER_ENCODING,
CONTENT_ENCODING,
LOCATION,
};
static void
UpdateRequestRange(Session *sess, unsigned long start, unsigned long end) {
int count =
snprintf(sess->httpRequestRange, 10+1+10+5, "%lu-%lu\r\n\r\n", start, end);
sess->desiredStart = start;
sess->desiredEnd = end;
sess->httpRequestLen = sess->httpRequestRange - sess->httpRequest + count;
}
Boolean BuildHTTPRequest(Session *sess, char *resourceStr) {
long sizeNeeded;
int rangeOffset;
int round = 0;
char *escapedStr = NULL;
if (strchr(resourceStr, ' ') != NULL) {
sizeNeeded = strlen(resourceStr);
if (sizeNeeded > 10000)
return FALSE;
escapedStr = malloc(sizeNeeded*3 + 1);
if (escapedStr == NULL)
return FALSE;
char *s = escapedStr;
char c;
while ((c = *resourceStr++) != '\0') {
if (c == ' ') {
*s++ = '%';
*s++ = '2';
*s++ = '0';
} else {
*s++ = c;
}
*s = '\0';
}
resourceStr = escapedStr;
}
sizeNeeded = 0;
do {
sizeNeeded = snprintf(sess->httpRequest, sizeNeeded,
"GET /%s HTTP/1.1\r\n"
"Host: %s\r\n"
"User-Agent: GS-NetDisk/" USER_AGENT_VERSION "\r\n"
"Accept-Encoding: identity\r\n"
//"Accept: */*\r\n" /* default, but some clients send explicitly */
//"Connection: Keep-Alive\r\n" /* same */
"Range: bytes=%n1234567890-1234567890\r\n"
"\r\n",
resourceStr,
sess->hostName+1,
&rangeOffset);
if (sizeNeeded <= 0) {
free(sess->httpRequest);
sess->httpRequest = NULL;
sess->httpRequestRange = NULL;
free(escapedStr);
return FALSE;
}
if (round == 0) {
sizeNeeded++; /* account for terminating NUL */
free(sess->httpRequest);
sess->httpRequest = malloc(sizeNeeded);
if (sess->httpRequest == NULL) {
sess->httpRequestRange = NULL;
free(escapedStr);
return FALSE;
}
}
} while (round++ == 0);
free(escapedStr);
sess->httpRequestRange = sess->httpRequest + rangeOffset;
UpdateRequestRange(sess, sess->desiredStart, sess->desiredEnd);
return TRUE;
}
enum NetDiskError
DoHTTPRequest(Session *sess, unsigned long start, unsigned long end) {
top:;
union {
srBuff srBuff;
rlrBuff rlrBuff;
} u;
Word tcpError;
Boolean wantRedirect = FALSE, gotRedirect = FALSE;
enum NetDiskError result;
UpdateRequestRange(sess, start, end);
sess->responseCode = 0;
/* Send out request */
result = NETWORK_ERROR;
unsigned int netErrors = 0;
TCPIPPoll();
if (sess->tcpLoggedIn) {
tcpError = TCPIPStatusTCP(sess->ipid, &u.srBuff);
if (tcpError || toolerror() || u.srBuff.srState != TCPSESTABLISHED) {
EndTCPConnection(sess);
}
}
u.rlrBuff.rlrBuffHandle = NULL;
netRetry:
if (!sess->tcpLoggedIn || netErrors) {
if (StartTCPConnection(sess) != 0)
goto errorReturn;
}
tcpError = TCPIPWriteTCP(sess->ipid, sess->httpRequest,
sess->httpRequestLen, TRUE, FALSE);
if (tcpError || toolerror()) {
if (netErrors == 0) {
netErrors++;
goto netRetry;
} else {
goto errorReturn;
}
}
/* Get response status line & headers */
LongWord startTime = GetTick();
do {
TCPIPPoll();
tcpError = TCPIPReadLineTCP(sess->ipid,
(void*)((LongWord)"\p\r\n\r\n" | 0x80000000),
buffTypeNewHandle, (Ref)NULL,
0xFFFFFF, &u.rlrBuff);
if (tcpError || toolerror()) {
if (netErrors == 0) {
netErrors++;
goto netRetry;
} else {
goto errorReturn;
}
}
} while (u.rlrBuff.rlrBuffCount == 0
&& GetTick() - startTime < HTTP_RESPONSE_TIMEOUT * 60);
result = NO_RESPONSE;
if (!u.rlrBuff.rlrIsDataFlag)
goto errorReturn;
result = INVALID_RESPONSE;
/* Response must be at least long enough for a status line & final CRLF */
if (u.rlrBuff.rlrBuffCount < 8+1+3+1+2+2)
goto errorReturn;
HLock(u.rlrBuff.rlrBuffHandle);
char *response = *u.rlrBuff.rlrBuffHandle;
char *responseEnd = response + u.rlrBuff.rlrBuffCount;
/* Make response a C-string. Specifically, it will end "CR LF NUL NUL". */
response[u.rlrBuff.rlrBuffCount - 2] = '\0';
response[u.rlrBuff.rlrBuffCount - 1] = '\0';
/* Parse status line of HTTP response */
char *endPtr;
if (strncmp(response, "HTTP/1.", 7) != 0)
goto errorReturn;
response += 7;
if (!(*response >= '1' && *response <= '9'))
goto errorReturn;
response += 1;
if (*response != ' ')
goto errorReturn;
response += 1;
errno = 0;
sess->responseCode = strtoul(response, &endPtr, 10);
if (errno || sess->responseCode > 999 || endPtr != response + 3)
goto errorReturn;
response += 3;
if (*response != ' ')
goto errorReturn;
response++;
while (*response != '\r')
response++;
response++;
if (*response != '\n')
goto errorReturn;
response++;
switch((unsigned int)sess->responseCode) {
/* "Partial content" response, as expected */
case 206:
break;
/* Redirect responses */
case 300: case 301: case 302: case 307: case 308:
if (sess->redirectCount < MAX_REDIRECTS) {
sess->redirectCount++;
wantRedirect = TRUE;
break;
} else {
result = EXCESSIVE_REDIRECTS;
goto errorReturn;
}
/* Full content in response to range request: not supported by NetDisk */
case 200:
result = NOT_DESIRED_CONTENT;
goto errorReturn;
default:
if (sess->responseCode < 400 || sess->responseCode > 599) {
result = UNSUPPORTED_RESPONSE;
} else {
result = sess->responseCode;
}
goto errorReturn;
}
/* Parse response headers */
sess->rangeStart = 0;
sess->rangeEnd = 0;
sess->totalLength = 0;
sess->contentLength = 0;
result = UNSUPPORTED_HEADER_VALUE;
while (response < responseEnd - 4) {
enum ResponseHeader header = UNKNOWN_HEADER;
if (wantRedirect) {
if (strncasecmp(response, "Location:", 9) == 0) {
response += 9;
header = LOCATION;
}
} else switch (_toupper(*response)) {
case 'C':
if (strncasecmp(response, "Content-Range:", 14) == 0) {
response += 14;
header = CONTENT_RANGE;
} else if (strncasecmp(response, "Content-Length:", 15) == 0) {
response += 15;
header = CONTENT_LENGTH;
} else if (strncasecmp(response, "Content-Encoding:", 17) == 0) {
response += 17;
header = CONTENT_ENCODING;
}
break;
case 'T':
if (strncasecmp(response, "Transfer-Encoding:", 18) == 0) {
response += 18;
header = TRANSFER_ENCODING;
}
break;
}
while (*response == ' ' || *response == '\t')
response++;
switch (header) {
case CONTENT_RANGE:
if (strncasecmp(response, "bytes ", 6) != 0)
goto errorReturn;
response += 6;
errno = 0;
sess->rangeStart = strtoul(response, &response, 10);
if (errno)
goto errorReturn;
if (*response != '-')
goto errorReturn;
response++;
sess->rangeEnd = strtoul(response, &response, 10);
if (errno || sess->rangeEnd == 0)
goto errorReturn;
if (*response != '/')
goto errorReturn;
response++;
/* require numeric total length, not indeterminate '*' */
sess->totalLength = strtoul(response, &response, 10);
if (errno || sess->totalLength == 0)
goto errorReturn;
break;
case CONTENT_LENGTH:
errno = 0;
sess->contentLength = strtoul(response, &endPtr, 10);
if (errno)
goto errorReturn;
if (sess->contentLength == 0 && !wantRedirect)
goto errorReturn;
response = endPtr;
break;
case CONTENT_ENCODING:
case TRANSFER_ENCODING:
if (strcasecmp(response, "identity") == 0) {
response += 8;
} else {
goto errorReturn;
}
break;
case LOCATION:
endPtr = response;
char c;
while ((c = *endPtr) != '\0' && c != '\r' && c != '\n')
endPtr++;
if (c == '\0' || c == '\n')
goto errorReturn;
while (endPtr > response
&& (*(endPtr-1) == ' ' || *(endPtr-1) == '\t')) {
c = *--endPtr;
}
if (wantRedirect) {
*endPtr = '\0';
if (SetURL(sess, response, FALSE, TRUE) != OPERATION_SUCCESSFUL) {
result = REDIRECT_ERROR;
goto errorReturn;
}
*endPtr = c;
response = endPtr;
gotRedirect = TRUE;
}
break;
/* Unknown headers: ignored */
case UNKNOWN_HEADER:
default:
while (*response != '\r')
response++;
break;
}
while ((*response == ' ' || *response == '\t') && response < responseEnd)
response++;
if (*response != '\r')
goto errorReturn;
response++;
if (*response != '\n')
goto errorReturn;
response++;
}
/* Wanted redirect: Retry with new location if we got it. */
if (wantRedirect) {
if (gotRedirect) {
DisposeHandle(u.rlrBuff.rlrBuffHandle);
goto top;
} else {
result = UNSUPPORTED_RESPONSE;
goto errorReturn;
}
}
/* See if we got what we wanted */
if (sess->expectedLength == 0) {
sess->expectedLength = sess->totalLength;
} else if (sess->totalLength != sess->expectedLength) {
result = DIFFERENT_LENGTH;
goto errorReturn;
}
result = NOT_DESIRED_CONTENT;
if (sess->rangeStart != sess->desiredStart)
goto errorReturn;
if (sess->rangeEnd != sess->desiredEnd)
goto errorReturn;
if (sess->contentLength != 0
&& sess->contentLength != (sess->desiredEnd - sess->desiredStart + 1))
goto errorReturn;
result = OPERATION_SUCCESSFUL;
DisposeHandle(u.rlrBuff.rlrBuffHandle);
return result;
errorReturn:
if (u.rlrBuff.rlrBuffHandle != NULL) {
DisposeHandle(u.rlrBuff.rlrBuffHandle);
}
/* Error condition on this TCP connection means it can't be reused. */
EndTCPConnection(sess);
return result;
}