Script to patch spotify ios sdk framework

.gitignore

@@ -1,3 +1,7 @@
 *.o
 *.dylib
 *.pcap
+SpotifyAudioPlayback
+spotifyThin
+spotNew
+

dump/Makefile

@@ -3,7 +3,7 @@ CFLAGS=-Wall -Wextra -Wmissing-declarations
 
 TARGET=dump.dylib
 HEADERS=shn.h pcap.h
-OBJECTS=dump.o shn.o pcap.o
+OBJECTS=dump.o shn.o pcap.o iosshn.o
 
 $(TARGET): $(OBJECTS)
 	$(CC) $(CFLAGS) -ldl -dynamiclib -o $@ $^

dump/dump-ios.sh

@@ -0,0 +1,16 @@
+# Update iosshn.c with file path for where to write dump.pcap
+# run 'make' to build required object files
+
+# Requires SpotifyAudioPlayback file from spotify ios sdk be copied into
+# this directory.  Produces a new replacement library spotNew.
+# Once script finishes, rename spotNew to SpotifyAudioPlayback and replace the old SpotifyAudioPlayback
+# in the ios-sdk directory.
+
+# Extract the x86 archive static library from fat file
+lipo SpotifyAudioPlayback -thin x86_64 -output spotifyThin
+# Remove the shannon object file from the archive
+ar -d spotifyThin shannon.c.o
+# Add in our new shannon implementation and logging code
+ar -r spotifyThin pcap.o shn.o iosshn.o
+# Package the archive back into a fat file
+lipo spotifyThin -create -output spotNew

dump/iosshn.c

@@ -0,0 +1,91 @@
+#include <stdio.h>
+#include <mach-o/dyld.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <fcntl.h>
+#include <string.h>
+#include <stdlib.h>
+#include <sys/mman.h>
+#include <execinfo.h>
+#include <unistd.h>
+#include <pthread.h>
+#include <dlfcn.h>
+#include <mach-o/getsect.h>
+#include <assert.h>
+
+#include "pcap.h"
+#include "shn.h"
+
+#define DIRECTION_SEND 0
+#define DIRECTION_RECV 1
+
+static int dump_fd;
+static int hasOpened = 0;
+
+static void initFile() {
+    dump_fd = open("Replace with path to directory /dump.pcap", O_CREAT | O_RDWR | O_TRUNC, 0644);
+    pcap_write_header(dump_fd, PCAP_DLT_USER0);
+    printf("Dump file initialized\n");
+}
+
+static void my_shn_encrypt(UCHAR * buf, int nbytes) {
+    struct timeval tv;
+    gettimeofday(&tv, NULL);
+    pcap_write_packet_header(dump_fd, &tv, 1 + nbytes);
+
+    uint8_t direction = DIRECTION_SEND;
+    write(dump_fd, &direction, 1);
+    write(dump_fd, buf, nbytes);
+}
+
+static void my_shn_decrypt(UCHAR * buf, int nbytes) {
+    static struct {
+        uint8_t cmd;
+        uint16_t length;
+    } __attribute__((packed)) header = { 0, 0 };
+
+    if (header.cmd == 0) {
+        assert(nbytes == 3);
+        memcpy(&header, buf, 3);
+    } else {
+        assert(nbytes == ntohs(header.length));
+
+        struct timeval tv;
+        gettimeofday(&tv, NULL);
+        pcap_write_packet_header(dump_fd, &tv, 4 + nbytes);
+
+        uint8_t direction = DIRECTION_RECV;
+        write(dump_fd, &direction, 1);
+        write(dump_fd, &header, 3);
+        write(dump_fd, buf, nbytes);
+
+        header.cmd = 0;
+    }
+}
+
+void sp_f2d2fa24b5944740acf40ea9f0fb352e (shn_ctx * c, UCHAR * buf, int nbytes) {
+	if (!hasOpened) {
+		initFile();
+		hasOpened = 1;
+	}
+	my_shn_encrypt(buf, nbytes);
+	shn_encrypt(c, buf, nbytes);
+}
+
+void sp_1e66e9e29aa743f3a4bfa4550da046fc (shn_ctx * c, UCHAR * buf, int nbytes) {
+	shn_decrypt(c, buf, nbytes);
+	my_shn_decrypt(buf, nbytes);
+}
+
+void sp_220e05475dd145729b07fb97feb11045 (shn_ctx * c, UCHAR * buf, int nbytes) {
+	shn_finish(c, buf, nbytes);
+}
+
+void sp_4765711b05524eaba8b74b531b892fa4 (shn_ctx * c, const UCHAR *key, int keylen) {
+    shn_key(c, key, keylen);
+}
+
+void sp_654f940627174249abb08c7051b7da5e (shn_ctx * c, const UCHAR *nonce, int noncelen) {
+    shn_nonce(c, nonce, noncelen);
+}