Using the iOS9 Compression Framework in Swift2 - ios

I have some NSData that is stored with the DEFLATE compression protocol?
DEFLATE Compression Method DEFLATE is a lossless compressed data
format that compresses data using a combination of the LZ77 algorithm
and Huffman coding, with efficiency comparable to the best currently
available general-purpose compression methods. The data can be
produced or consumed, even for an arbitrarily long sequentially
presented input data stream, using only a priority-bounded amount of
intermediate storage. The format can be implemented readily in a
manner not covered by patents. Specifications for DEFLATE can be found
in RFC 1951 - DEFLATE Compressed Data Format Specification, May 1996.
If I understand it correctly in IOS9 there is a new Compression Framework which "might" handle this case. The documentation lists the following supported algorithms: LZFSE, LZ4, LZMA, and ZLIB level 5.
I'm not sure but I believe ZLIB supports the LZ77 Deflate algorithm. The question I have is how do I actually use this framework:
So I believe the function i want to use is compression_decode_buffer
#available(iOS 9.0, *)
public func compression_decode_buffer(
dst_buffer: UnsafeMutablePointer<UInt8>,
_ dst_size: Int,
_ src_buffer: UnsafePointer<UInt8>,
_ src_size: Int,
_ scratch_buffer: UnsafeMutablePointer<Void>,
_ algorithm: compression_algorithm) -> Int
but I'm not sure exactly how to utilize this algorithm.
So from reading the header it looks like i need an input size dst_size: bytes.size and output size a inputBuffer an &outputbuffer and a compression algorithm
dst_buffer: UnsafeMutablePointer,
_ dst_size: Int,
_ src_buffer: UnsafePointer,
_ src_size: Int,
_ scratch_buffer: UnsafeMutablePointer,
_ algorithm: compression_algorithm) -> Int
Assuming i have some sample data (see below)
let bytes : [UInt8] = [ .... ] // see below
compression_decode_buffer(
<DST_BUFFER>,
<DST_SIZE>,
bytes,
bytes.count,
<SCRATCH_BUFFER>,
COMPRESSION_ZLIB
)
Where i'm at a loss is as to what goes into <DST_BUFFER>, <DST_SIZE>, <SCRATCH_BUFFER>.
Any suggestions?
Sample Data
let bytes : [UInt8] = [0x7e, 0x07, 0x07, 0xff, 0xff, 0x41, /* <1~....A */
0x10, 0x33, 0x51, 0x3e, 0x94, 0xb2, 0xa0, 0x27, /* .3Q>...' */
0x80, 0x00, 0x21, 0x65, 0x26, 0xd8, 0x22, 0x10, /* ..!e&.". */
0x2c, 0xd5, 0x99, 0x00, 0x00, 0x44, 0xbb, 0xd4, /* ,....D.. */
0x54, 0x38, 0xf5, 0x01, 0x36, 0xd1, 0x20, 0x2c, /* T8..6. , */
0xd5, 0x99, 0xbb, 0x1c, 0xaf, 0xc3, 0x2c, 0x60, /* ......,` */
0xcb, 0x0c, 0x79, 0xcb, 0x76, 0xa0, 0x84, 0xd5, /* ..y.v... */
0x99, 0x83, 0x1c, 0xaf, 0xc3, 0x2c, 0x60, 0x35, /* .....,`5 */
0x66, 0x60, 0x49, 0x76, 0x60, 0xc7, 0x5b, 0xf3, /* f`Iv`.[. */
0xce, 0x05, 0x08, 0x3a, 0x04, 0x13, 0x4a, 0x00, /* ...:..J. */
0x92, 0x05, 0x08, 0x17, 0x14, 0x68, 0x31, 0xc3, /* .....h1. */
0x1c, 0xb2, 0xc3, 0x1e, 0x72, 0xdd, 0xe0, 0x00, /* ....r... */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* ........ */
0x00, 0x00, 0x00, 0x00, 0x27, 0x00, 0x00, 0x00, /* ....'... */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x30, /* .......0 */
0x8e, 0x7e]

Generally compression_decode_buffer() is used like this:
import Compression
let bytes : [UInt8] = [ .... ] // Compressed data
var dst = [UInt8](count: 1000, repeatedValue: 0) // destination buffer
let size = compression_decode_buffer(&dst, dst.count, bytes, bytes.count, nil, COMPRESSION_ZLIB)
The destination buffer must be large enough for the decompressed data.
On return, size is the number of bytes that were written to the
destination buffer (or zero if the decompression failed).
(There is also a "streaming" interface
compression_stream_init()
compression_stream_process()
compression_stream_destroy()
which can be used to process the data in chunks.)
However, I tried to decompress your data with all available
COMPRESSION_XXX methods without success.
From my experiments it seems that COMPRESSION_ZLIB corresponds
to the "raw deflate" method, i.e. what you get with the zlib
deflateInit2() function if the windowBits parameter is set
to a negative value.

Related

Sending Deauthentication Packets by esp8266

I am trying to implement a simple WiFi deauther using my nodemcu but i can't see any disconnection b/w AP(my android's hotspot) & Station ( my second android device)
But when i am using a third party tool like Wi-PWN ( available on GitHub ) , is working.
So its clear that i am doing something wrong in Deauthentication process
Here is some parts of code
// Channel to perform deauth
uint8_t channel = 0;
// Packet buffer
uint8_t packet_buffer[128];
// DeAuth template
uint8_t template_da[26] = {
0xc0, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0xCC, 0xCC, 0xCC, 0xCC,
0xCC, 0xCC, 0x00, 0x00, 0x01,
0x00};
uint16_t create_packet(uint8_t *buf, uint8_t *client, uint8_t *ap, uint8_t type)
{
int i = 0;
memcpy(buf, template_da, 26);
// Destination
memcpy(buf + 4, client, ETH_MAC_LEN);
// Sender
memcpy(buf + 10, ap, ETH_MAC_LEN);
buf[0] = type;
return 26;
}
/* Sends deauth packets. */
void deauth(uint8_t *c, uint8_t *ap, uint16_t seq)
{
uint8_t i = 0;
uint16_t sz = 0;
sz = create_packet(packet_buffer, c, ap, 0xc0); // 0xc0 for deauth
wifi_send_pkt_freedom(packet_buffer, sz, 0);
sz = create_packet(packet_buffer, c, ap, 0xa0); // xa0 for disassociation
wifi_send_pkt_freedom(packet_buffer, sz, 0);
delay(1);
}
}
Edit : I know the mac address of both AP & Station so there could be no mistake in filling mac while creating packet.

iOS SDL2 OpenGL ES Cannot Draw Texture

I have been trying to follow the below example but using iOS/Xcode instead of VS2015 (which shows an example of an Android cross-platform project).
Youtube Link
I cannot get the code to display any of my texture at all. No matter what I try I only get a small white rectangle. What am I doing wrong?
This should be OpenGL ES1.x so no shaders should be required.
#import <Foundation/Foundation.h>
#include "SDL.h"
#include <time.h>
#include "SDL_opengles.h"
#define FALSE 0
#define TRUE 1
#ifndef BOOL
#define BOOL int
#endif
#define min(a,b) ((a) < (b) ? (a) : (b))
#define max(a,b) ((a) > (b) ? (a) : (b))
#define SCREEN_WIDTH 320
#define SCREEN_HEIGHT 480
GLuint g_Texture = 0;
BOOL g_Running = TRUE;
SDL_Window *g_SDLWindow = NULL;
SDL_Surface *g_SDLSurface = NULL;
SDL_Renderer *g_SDLRenderer = NULL;
SDL_Texture *g_SDLTexture = NULL;
int g_ScreenHeight = SCREEN_HEIGHT;
int g_ScreenWidth = SCREEN_WIDTH;
unsigned char treeData[420] = {
0x00, 0x00, 0x0A, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x10, 0x00, 0x10, 0x00, 0x20, 0x08, 0x82, 0x00, 0x00, 0x00, 0x00, 0x01,
0x16, 0x1D, 0x38, 0xFF, 0x10, 0x50, 0x6C, 0xFF, 0x83, 0x16, 0x1D, 0x38,
0xFF, 0x00, 0x10, 0x50, 0x6C, 0xFF, 0x82, 0x16, 0x1D, 0x38, 0xFF, 0x82,
0x00, 0x00, 0x00, 0x00, 0x83, 0x00, 0x00, 0x00, 0x00, 0x81, 0x16, 0x1D,
0x38, 0xFF, 0x00, 0x10, 0x50, 0x6C, 0xFF, 0x84, 0x16, 0x1D, 0x38, 0xFF,
0x83, 0x00, 0x00, 0x00, 0x00, 0x85, 0x00, 0x00, 0x00, 0x00, 0x82, 0x16,
0x1D, 0x38, 0xFF, 0x00, 0x10, 0x50, 0x6C, 0xFF, 0x85, 0x00, 0x00, 0x00,
0x00, 0x85, 0x00, 0x00, 0x00, 0x00, 0x01, 0x16, 0x1D, 0x38, 0xFF, 0x10,
0x50, 0x6C, 0xFF, 0x81, 0x16, 0x1D, 0x38, 0xFF, 0x85, 0x00, 0x00, 0x00,
0x00, 0x85, 0x00, 0x00, 0x00, 0x00, 0x83, 0x16, 0x1D, 0x38, 0xFF, 0x85,
0x00, 0x00, 0x00, 0x00, 0x85, 0x00, 0x00, 0x00, 0x00, 0x03, 0x16, 0x1D,
0x38, 0xFF, 0x10, 0x50, 0x6C, 0xFF, 0x16, 0x1D, 0x38, 0xFF, 0x10, 0x50,
0x6C, 0xFF, 0x85, 0x00, 0x00, 0x00, 0x00, 0x82, 0x00, 0x00, 0x00, 0x00,
0x89, 0x24, 0xBA, 0x24, 0xFF, 0x82, 0x00, 0x00, 0x00, 0x00, 0x81, 0x00,
0x00, 0x00, 0x00, 0x87, 0x24, 0xBA, 0x24, 0xFF, 0x00, 0x1A, 0x87, 0x2F,
0xFF, 0x82, 0x24, 0xBA, 0x24, 0xFF, 0x81, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x82, 0x24, 0xBA, 0x24, 0xFF, 0x00, 0x1A, 0x87,
0x2F, 0xFF, 0x81, 0x24, 0xBA, 0x24, 0xFF, 0x00, 0x1A, 0x87, 0x2F, 0xFF,
0x86, 0x24, 0xBA, 0x24, 0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x8F, 0x24,
0xBA, 0x24, 0xFF, 0x81, 0x24, 0xBA, 0x24, 0xFF, 0x00, 0x1A, 0x87, 0x2F,
0xFF, 0x86, 0x24, 0xBA, 0x24, 0xFF, 0x05, 0x1A, 0x87, 0x2F, 0xFF, 0x24,
0xBA, 0x24, 0xFF, 0x1A, 0x87, 0x2F, 0xFF, 0x24, 0xBA, 0x24, 0xFF, 0x1A,
0x87, 0x2F, 0xFF, 0x24, 0xBA, 0x24, 0xFF, 0x86, 0x24, 0xBA, 0x24, 0xFF,
0x00, 0x1A, 0x87, 0x2F, 0xFF, 0x87, 0x24, 0xBA, 0x24, 0xFF, 0x81, 0x24,
0xBA, 0x24, 0xFF, 0x02, 0x1A, 0x87, 0x2F, 0xFF, 0x24, 0xBA, 0x24, 0xFF,
0x1A, 0x87, 0x2F, 0xFF, 0x8A, 0x24, 0xBA, 0x24, 0xFF, 0x00, 0x00, 0x00,
0x00, 0x00, 0x88, 0x24, 0xBA, 0x24, 0xFF, 0x02, 0x1A, 0x87, 0x2F, 0xFF,
0x24, 0xBA, 0x24, 0xFF, 0x1A, 0x87, 0x2F, 0xFF, 0x81, 0x24, 0xBA, 0x24,
0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x81, 0x00, 0x00, 0x00, 0x00, 0x84,
0x24, 0xBA, 0x24, 0xFF, 0x00, 0x1A, 0x87, 0x2F, 0xFF, 0x85, 0x24, 0xBA,
0x24, 0xFF, 0x81, 0x00, 0x00, 0x00, 0x00, 0x83, 0x00, 0x00, 0x00, 0x00,
0x87, 0x24, 0xBA, 0x24, 0xFF, 0x83, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x54, 0x52, 0x55, 0x45, 0x56, 0x49,
0x53, 0x49, 0x4F, 0x4E, 0x2D, 0x58, 0x46, 0x49, 0x4C, 0x45, 0x2E, 0x00
};
void LoadTree( void )
{
glGenTextures( 1, &g_Texture );
glBindTexture( GL_TEXTURE_2D, g_Texture );
glTexImage2D( GL_TEXTURE_2D, 0, GL_RGBA, 16, 16, 0, GL_RGBA, GL_UNSIGNED_BYTE, treeData+18 );
}
//--------------------------------------------------------------------------------------------
// InitSDL()
//--------------------------------------------------------------------------------------------
void InitSDL( void )
{
if( SDL_Init( SDL_INIT_VIDEO ) < 0 )
exit( -1 );
atexit( SDL_Quit );
SDL_GL_SetAttribute( SDL_GL_DOUBLEBUFFER, 1 ); // *new*
SDL_DisplayMode currentDisplay;
SDL_GetCurrentDisplayMode( 0, &currentDisplay );
g_ScreenWidth = max( currentDisplay.w, currentDisplay.h );
g_ScreenHeight = min( currentDisplay.w, currentDisplay.h );
SDL_DisplayMode displayMode;
SDL_GetDesktopDisplayMode( 0, &displayMode );
SDL_GL_SetAttribute( SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_ES );
// PDS: GLES 2 will require shaders etc..
//SDL_GL_SetAttribute( SDL_GL_CONTEXT_MAJOR_VERSION, 2 );
SDL_GL_SetAttribute( SDL_GL_CONTEXT_MAJOR_VERSION, 1 );
SDL_GL_SetAttribute( SDL_GL_CONTEXT_MINOR_VERSION, 1 );
g_SDLWindow = SDL_CreateWindow( "Test",
SDL_WINDOWPOS_UNDEFINED,
SDL_WINDOWPOS_UNDEFINED,
g_ScreenWidth,
g_ScreenHeight,
/* SDL_WINDOW_FULLSCFREEN | */ SDL_WINDOW_OPENGL );
if( g_SDLWindow == NULL )
exit( -1 );
SDL_GL_CreateContext( g_SDLWindow );
glViewport( 0, 0, g_ScreenWidth, g_ScreenHeight ); // Reset The Current Viewport
glMatrixMode( GL_PROJECTION ); // Select The Projection Matrix
glLoadIdentity(); // Reset The Projection Matrix
glRotatef( -90, 0, 0, 1 );
glOrthof( 0.0f, g_ScreenWidth, g_ScreenHeight, 0.0f, -1.0f, 1.0f );
glMatrixMode( GL_MODELVIEW ); // Select The Modelview Matrix
glLoadIdentity(); // Reset The Modelview Matrix
glTranslatef(0.5, 0.5, 0);
glClearColor( 0.9f, 0.9f, 0.9f, 1.0f );
glClear( GL_COLOR_BUFFER_BIT );
LoadTree();
glShadeModel(GL_SMOOTH);
}
float sq[] =
{
-7, 7, 0,
7, 7, 0,
-7, -7, 0,
7, -7, 0
};
float tri[] =
{
sq[ 0 ], sq[ 1 ], sq[ 2 ],
sq[ 3 ], sq[ 4 ], sq[ 5 ],
sq[ 6 ], sq[ 7 ], sq[ 8 ],
sq[ 6 ], sq[ 7 ], sq[ 8 ],
sq[ 3 ], sq[ 4 ], sq[ 5 ],
sq[ 9 ], sq[ 10], sq[ 11]
};
float texCoords[]=
{
0, 1,
1, 1,
0, 0,
0, 0,
1, 1,
1, 0
};
//--------------------------------------------------------------------------------------------
// Draw()
//--------------------------------------------------------------------------------------------
void Draw( int x, int y )
{
glEnable( GL_TEXTURE_2D );
glMatrixMode( GL_MODELVIEW );
glLoadIdentity();
glBindTexture( GL_TEXTURE_2D, g_Texture );
glPushMatrix();
glDisable( GL_BLEND );
glDisable( GL_CULL_FACE );
glEnable( GL_TEXTURE_2D );
GLfloat tX = (GLfloat) 10.0f;
GLfloat tY = (GLfloat) 10.0f;
GLfloat xOffset = 0;
GLfloat yOffset = 0;
// PDS: Offset the drawing by half character width since all placement will be done from quad centre..
xOffset = tX;
yOffset = tY;
glTranslatef( xOffset + x, yOffset + y, 0.0f);
glEnableClientState( GL_VERTEX_ARRAY );
glEnableClientState( GL_TEXTURE_COORD_ARRAY );
glFrontFace( GL_CW );
glVertexPointer( 3, GL_FLOAT, 0, tri );
glTexCoordPointer( 2, GL_FLOAT, 0, texCoords );
glDrawArrays( GL_TRIANGLES, 0, 6 );
glDisableClientState( GL_TEXTURE_COORD_ARRAY );
glDisableClientState( GL_VERTEX_ARRAY );
glDisableClientState( GL_COLOR_ARRAY );
glPopMatrix();
glBindTexture( GL_TEXTURE_2D, 0 );
glEnable( GL_BLEND );
}
//--------------------------------------------------------------------------------------------
// main()
//--------------------------------------------------------------------------------------------
int main( int argc, char* argv[] )
{
InitSDL();
SDL_Event event;
while( g_Running )
{
while( SDL_PollEvent( &event ) )
{
switch( event.type )
{
case SDL_QUIT:
g_Running = false;
break;
}
}
Draw( 100, 100 );
SDL_GL_SwapWindow( g_SDLWindow );
}
SDL_Quit();
return EXIT_SUCCESS;
}
I figured this out.. The ordering of setting the Projection and ModelView uniforms was wrong - it had to be done after the shader program was in use.. and I had some crazy vertice values for the triangles making up the destination rectangle.
The raw TGA loading didn't work very well either so I went back to my original code for loading TGA files.
The below link contains a working example.
Working Example

convert c char to swift

I am trying to conver the following code to swift:
static unsigned char rsa2048Asn1Header[] = {
0x30, 0x82, 0x01, 0x22, 0x30, 0x0d, 0x06, 0x09, 0x2a, 0x86, 0x48, 0x86,
0xf7, 0x0d, 0x01, 0x01, 0x01, 0x05, 0x00, 0x03, 0x82, 0x01, 0x0f, 0x00
};
static unsigned char rsa4096Asn1Header[] = {
0x30, 0x82, 0x02, 0x22, 0x30, 0x0d, 0x06, 0x09, 0x2a, 0x86, 0x48, 0x86,
0xf7, 0x0d, 0x01, 0x01, 0x01, 0x05, 0x00, 0x03, 0x82, 0x02, 0x0f, 0x00
};
static unsigned char ecDsaSecp256r1Asn1Header[] = {
0x30, 0x59, 0x30, 0x13, 0x06, 0x07, 0x2a, 0x86, 0x48, 0xce, 0x3d, 0x02,
0x01, 0x06, 0x08, 0x2a, 0x86, 0x48, 0xce, 0x3d, 0x03, 0x01, 0x07, 0x03,
0x42, 0x00
};
static unsigned char *asn1HeaderBytes[3] = { rsa2048Asn1Header, rsa4096Asn1Header, ecDsaSecp256r1Asn1Header };
static unsigned int asn1HeaderSizes[3] = { sizeof(rsa2048Asn1Header), sizeof(rsa4096Asn1Header), sizeof(ecDsaSecp256r1Asn1Header) };
My swift code looks like this:
let rsa2048Asn1Header:[CUnsignedChar] = [0x30, 0x82, 0x01, 0x22, 0x30, 0x0d, 0x06, 0x09, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d,0x01, 0x01, 0x01, 0x05, 0x00, 0x03, 0x82, 0x01, 0x0f, 0x00]
let rsa4096Asn1Header:[CUnsignedChar] = [0x30, 0x82, 0x01, 0x22, 0x30, 0x0d, 0x06, 0x09, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x01, 0x01, 0x05, 0x00, 0x03, 0x82, 0x01, 0x0f, 0x00]
let ecDsaSecp256r1Asn1Header:[CUnsignedChar] = [0x30, 0x59, 0x30, 0x13, 0x06, 0x07, 0x2a, 0x86, 0x48, 0xce, 0x3d, 0x02, 0x01, 0x06, 0x08, 0x2a, 0x86, 0x48, 0xce, 0x3d, 0x03, 0x01, 0x07, 0x03, 0x42, 0x00]
let asn1HeaderBytes:[[CUnsignedChar]] = [rsa2048Asn1Header, rsa4096Asn1Header, ecDsaSecp256r1Asn1Header]
let asn1HeaderSizes:[UInt] = [sizeof(rsa2048Asn1Header.dynamicType).toUInt, sizeof(rsa4096Asn1Header.dynamicType).toUInt, sizeof(ecDsaSecp256r1Asn1Header.dynamicType).toUInt]
However i failing at his badly, per example using rsa2048Asn1Header and converting it to NSData:
let data:NSData = NSData(bytes: rsa2048Asn1Header, length:strideofValue(rsa2048Asn1Header))
swift prints with length 8:
<30820122 300d0609>
objc for the following code:
[NSData dataWithBytes:rsa2048Asn1Header length:sizeof(rsa2048Asn1Header)];
prints
<30820122 300d0609 2a864886 f70d0101 01050003 82010f00> size: 24
looking at apple documentation, strideOfvalue should return the right size for each one of those [CUnsignedChar] but that doesnt seem to be the case, my question is shouldnt a [CUnsignedChar] have same size as usigned char [] in objc, if not what could i use to change?
also [[CUnsignedChar]] makes no sense whatsoever in my head, how would the code below convert to swift, should i convert those arrays to an NSString and extract the CString when required, if so what encoding should I use?
static unsigned char *asn1HeaderBytes[3] = { rsa2048Asn1Header, rsa4096Asn1Header, ecDsaSecp256r1Asn1Header };
I don't think strideofValue is the function you are looking for. I haven't heard of it before, but the documentation states:
Returns the least possible interval between distinct instances of T in memory. The result is always positive.
If this is returning 8, that means that the minimum distance between [CUnsignedChar]s in memory is 8 bytes.
To use NSData(data:length:) properly, the second parameter needs to be the size of the array. You can use the count property for this:
let data: NSData = NSData(bytes: rsa2048Asn1Header, length:rsa2048Asn1Header.count)
[[CUnsignedChar]] is an array of arrays (two-dimensional array) of CUnsignedChar.
Your headers are raw bytes, so technically no encoding is 'correct' to convert to NSString. The cryptographic headers you have don't appear to be strings, and contain unprintable characters.
You should not use strideofValue function. 'strideofValue' it's not a replacement for 'sizeof'. Just go for ".count" property.

avcodec_decode_audio4 decoded data different on device and simulator

I'm having issues where the decoded audio sounds punchy/garbled simply can't tell what is being heard when decoded on an iPhone/iPad device. However, when decoding the audio on simulator the audio is perfect.
I do realize emulator runs on a different CPU architecture i386 while actual device is ARMv7 so the issue could be something around that.
I have printed the compressed data on device and simulator before being decoded and it matches. Then I printed the decoded data for device and simulator and they are different. That leads me to think something is happening with the decoder. I can see that it is not a byte swap issue since the data is just completely different.
Any ideas on what I could or look into? I don't have this issue on Android...
First decoded audio frame.
DEVICE:
0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x70, 0x08, 0x00, 0x00, 0x00, 0x00, 0x03, 0x00, 0xda, 0x0a, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
EMULATOR:
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
UPDATE 1
I was able to resolve the issue by disabling asm with --disable-asm. Something must not be working correctly with the ARM asm files.

Decoding H.264 stream from dvr

I have a security DVR that uses h264 streams. I have been trying to get this to work with zoneminder. I have successfully logged into the dvr and recieved some form of data streams. The data stream is dumped to a fifo/pipe, and then zoneminder uses ffmpeg to read this in.
Note: i know very very little about h.264 streams. just enough to be stupid.
The video only updates about every 15 seconds in ZM. I can dump the stream to a file with ffmpeg or avconv (avconv -i /tmp/mypipe cam.mp4) but it is still not right. However, the file created by avconv is WAY WAY better than the one created by ffmpeg.
I've included a link to the wireshark dump (I did change the PW and login info, etc...). From the data, It appears that the dvr is adding a header to the h264 data streams. I understand that the h264 stream starts with a (0x00 00 01 67) or (0x00 00 01 61). Here is an example of the header plus start of stream:
0x33, 0x30, 0x64, 0x63, 0x48, 0x32, 0x36, 0x34,
0x3f, 0x55, 0x00, 0x00, 0x08, 0x00, 0x20, 0x00,
0xa2, 0x7a, 0xea, 0xdc, 0xcf, 0x08, 0x00, 0x00,
0x0d, 0x0a, 0x11, 0x07, 0x13, 0x20, 0x00, 0x00,
0x00, 0x00, 0x00, 0x01, 0x67, 0x42, 0xe0, 0x14,
0xdb, 0x05, 0x87, 0xc4, 0x00, 0x00, 0x00, 0x01,
0x68, 0xce, 0x30, 0xa4, 0x80, 0x00, 0x00, 0x00,
0x01, 0x06, 0xe5, 0x01, 0x51, 0x80, 0x00, 0x00,
0x00, 0x01, 0x65, 0xb8, 0x00, 0x01, 0xa8, 0xac,
I can see that there are a few frame indicators in this message. The DVR's header appears to be 32 bytes long in this case, and in some other messages in the dump, it appears to be 24 bytes long. I am striping the header off before I dump the stream to the pipe. (I have verified the output doesn't include the dvr's headers in any way.
What I would like help with is determining what I should be sending to the pipe. should I start with the first h.264 key? Is there something out of order? I'm very surprised that ffmpeg is only getting 15 second updates, but avconv is much better (lots of dropped frames, and playback is "sped up".
using ffmpeg to read the pipe produces a file that shows it's codec as: H264 - MPEG-4 AVC (part 10) (avc1) with a Decoded format: Planar 4:2:0 YUV using vlc.
Appreciate any help you can provide!
Wireshark h264 dump
edit: on Ubuntu 13.04
ffmpeg version: 6:0.8.6-1ubuntu2
avconv 0.8.6-6:0.8.6-1ubuntu2

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