Various components in user, kernel, and secure kernel work together to update the system. All the relevant libraries are documented in this one page because they work close together.
SceCuiSetUpper
Module
This is a user application that is found inside the update PUP. It has not been seen used outside of development units but is included in retail updates. It does not change often between firmware updater versions.
Known NIDs
| Version |
Name |
World |
Privilege |
NID
|
| 2.12
|
SceCuiSetUpper |
Non-secure |
User |
0x8802DAE9
|
Libraries
This module does not export any library.
ScePsp2Swu
Module
This is a user application that is found inside the update PUP, and extracted to ud0:UPDATE/.
Known NIDs
| Version |
Name |
World |
Privilege |
NID
|
| 1.69 |
ScePsp2Swu |
Non-secure |
User |
0xF8D9C101
|
Libraries
This module does not export any library.
SceSblUpdateMgr
Module
This module exists only in the non-secure kernel. The SELF can be found in bootfs:update_mgr.skprx.
Known NIDs
| Version |
Name |
World |
Privilege |
NID
|
| 1.69 |
SceSblUpdateMgr |
Non-secure |
Kernel |
0xBA91FE90
|
| 3.60 |
SceSblUpdateMgr |
Non-secure |
Kernel |
0x528F6BF5
|
Libraries
This module exports libraries to both kernel and user.
Known NIDs
| Version
|
Name
|
World
|
Visibility
|
NID
|
| 0.931-1.69 |
SceSblUpdateMgrForKernel |
Non-secure |
Kernel |
0xC4466E48
|
| 0.931-1.69 |
SceSblUpdateMgrForDriver |
Non-secure |
Kernel |
0x0E04CD3D
|
| 0.931-3.60 |
SceSblSsUpdateMgr |
Non-secure |
User |
0x31406C49
|
| 0.990 |
SceSblSsUpdateMgrAdditional |
Non-secure |
User |
0xBDD7A86F
|
Types
typedef char SceUpdateMode;
typedef struct SceSblUsSpkgInfo { // Size is 0x10 on FW 0.931-0.990
SceSize size; // size of this structure
int version;
int reserved1;
int reserved2;
} SceSblUsSpkgInfo;
typedef struct SceKernelSpackageArgs { // Size is 0x2C on FW 0.931
SceSize arg_size; // Size of this structure
SceUInt32 package_type;
void *addr;
SceSize size;
SceUInt32 flags;
char unk[0x8];
SceUInt32 seq_no;
SceUInt32 result;
SceUInt32 progress;
SceUInt32 written_rates;
} SceKernelSpackageArgs;
SceSblUpdateMgrForKernel
SceSblUpdateMgrForKernel functions and NIDs are exactly identical to SceSblUpdateMgrForDriver.
SceSblUpdateMgrForDriver
sceSblUsVerifyPupForDriver
| Version |
NID
|
| 0.931-0.940 |
0xD593D613
|
int sceSblUsVerifyPupForDriver(const char *path);
| Version |
NID
|
| 0.931-0.940 |
0xBAFCA304
|
int sceSblUsVerifyPupHeaderForDriver(const char *path);
sceSblUsVerifyPupSegmentForDriver
| Version |
NID
|
| 0.931-0.940 |
0xF43372C4
|
int sceSblUsVerifyPupSegmentForDriver(const char *path);
sceSblUsVerifyPupSegmentByIdForDriver
| Version |
NID
|
| 0.931-0.940 |
0xB4AC7684
|
int sceSblUsVerifyPupSegmentByIdForDriver(const char *path, void *arg2, int seg_id, int arg4);
sceSblUsVerifyPupWatermarkForDriver
| Version |
NID
|
| 0.931-0.940 |
0xDD90C4B9
|
int sceSblUsVerifyPupWatermarkForDriver(const char *path);
sceSblUsUpdateSpackageForDriver
| Version |
NID
|
| 0.931-0.990 |
0xF41138F1
|
int sceSblUsUpdateSpackageForDriver(int package_type, void *kaddr, SceSize size, uint32_t flags, int *pRequestId);
sceSblUsInspectSpackageForDriver
| Version |
NID
|
| 0.931-0.990 |
0xE7F5A4C0
|
int sceSblUsInspectSpackageForDriver(int package_type, void *kaddr, SceSize size, uint32_t flags, int *pRequestId);
| Version |
NID
|
| 0.931-0.990 |
0x87AC6E73
|
int sceSblUsExtractSpackageForDriver(int package_type, void *kaddr, SceSize size, uint32_t flags, int *pRequestId);
sceSblUsAllocateBufferForDriver
| Version |
NID
|
| 0.931-0.990 |
0x2D69BFDC
|
int sceSblUsAllocateBufferForDriver(SceSize size, void **kaddr);
sceSblUsReleaseBufferForDriver
| Version |
NID
|
| 0.931-0.990 |
0x45B91736
|
int sceSblUsReleaseBufferForDriver(void *kaddr);
sceSblUsGetStatusForDriver
| Version |
NID
|
| 0.931-0.990 |
0x99D57D18
|
int sceSblUsGetStatusForDriver(int node_type, int requestId, uint32_t *seq_no, uint32_t *result, uint32_t *progress, uint32_t *written_rates);
sceSblUsGetSpkgInfoForDriver
| Version |
NID
|
| 0.931-0.990 |
0xAE7D3BF5
|
int sceSblUsGetSpkgInfoForDriver(int package_type, SceSblUsSpkgInfo *pInfo);
sceSblUsGetUpdateModeForDriver
| Version |
NID
|
| 0.931-0.990 |
0xEEC71CCC
|
Get UpdateMode from Ernie NVS. See SceSblSsMgr#NVS_Areas.
int sceSblUsGetUpdateModeForDriver(SceUpdateMode *mode);
sceSblUsSetUpdateModeForDriver
| Version |
NID
|
| 0.931-0.990 |
0x266820E9
|
Set UpdateMode to Ernie NVS. See SceSblSsMgr#NVS_Areas.
int sceSblUsSetUpdateModeForDriver(SceUpdateMode mode);
SceSblUpdateMgrForDriver_6ACEF44D
| Version |
NID
|
| 0.931-0.990 |
0x6ACEF44D
|
Only return 0.
int SceSblUpdateMgrForDriver_6ACEF44D(void);
sceSblUsPowerControlForDriver
| Version |
NID
|
| 0.931-0.990 |
0x64ECC81A
|
int sceSblUsPowerControlForDriver(int mode, int flag);
sceSblUsGetApplicableVersionForDriver
| Version |
NID
|
| 0.931-0.990 |
0x7CC73839
|
// type must be 1 or 9 else "builtin revoke list cannot be found"
int sceSblUsGetApplicableVersionForDriver(int type, void *versionBuf);
SceSblSsUpdateMgrAdditional
sceSblUsInformUpdateStartedForUser
| Version |
NID
|
| 0.990 |
0x1E40A14E
|
sceSblUsInformUpdateOngoingForUser
| Version |
NID
|
| 0.990 |
0x3A917CCE
|
sceSblUsInformUpdateFinishedForUser
| Version |
NID
|
| 0.990 |
0x4734B987
|
sceSblUsSetSwInfoIntForUser
| Version |
NID
|
| 0.990 |
0xA870D285
|
int sceSblUsSetSwInfoIntForUser(char *str, SceSize len, SceUInt32 number);
sceSblUsSetSwInfoStrForUser
| Version |
NID
|
| 0.990 |
0x8C7255C8
|
int sceSblUsSetSwInfoStrForUser(char *str1, SceSize len1, char *str2, SceSize len2);
sceSblUsSetSwInfoBinForUser
| Version |
NID
|
| 0.990 |
0xF157E34A
|
int sceSblUsSetSwInfoBinForUser(char *str1, SceSize len1, char *str2, SceSize len2);
SceSblSsUpdateMgr
sceSblUsGetUpdateModeForUser
| Version |
NID
|
| 0.931-3.60 |
0x8E834565
|
Temp name was sceSblSsUpdateMgrGetBootMode.
Get UpdateMode from Ernie NVS. See SceSblSsMgr#NVS_Areas.
int sceSblUsGetUpdateModeForUser(SceUpdateMode *mode);
sceSblUsSetUpdateModeForUser
| Version |
NID
|
| 0.931-3.60 |
0xC725E3F0
|
Temp name was sceSblSsUpdateMgrSetBootMode.
Set UpdateMode to Ernie NVS. See SceSblSsMgr#NVS_Areas.
int sceSblUsSetUpdateModeForUser(SceUpdateMode mode);
sceSblUsPowerControlForUser
| Version |
NID
|
| 0.931-3.60 |
0x1825D954
|
Temp name was sceSblSsUpdateMgrSendCommand.
// Modes:
// 0: reboot target and/or CP with or without CP update. flag 2 = reboot CP, flag 5 = reboot Ernie
// 1: shutdown target. flag 5 = shutdown Ernie
// 2: sceKernelPowerLock(0)
// 3: sceKernelPowerUnlock(0)
// 4: LED ON
// 5: LED OFF
// 6: LED INIT
int sceSblUsPowerControlForUser(int mode, int flag);
sceSblUsGetSpkgInfoForUser
| Version |
NID
|
| 0.931-3.60 |
0x8E3EC2E1
|
Temp name was sceSblSsUpdateMgrGetSpkgInfo.
int sceSblUsGetSpkgInfoForUser(int package_type, SceSblUsSpkgInfo *pInfo);
sceSblUsVerifyPupForUser
| Version |
NID
|
| 0.931-3.60 |
0x6F5EDBF4
|
path max len : 0x3FF bytes
int sceSblUsVerifyPupForUser(const char *path);
sceSblUsVerifyPupAdditionalSignForUser
| Version |
NID
|
| 0.990 |
NOT PRESENT
|
| 3.60 |
0xB19366CB
|
path max len : 0x3FF, path len >= 0x400 : error
int sceSblUsVerifyPupAdditionalSignForUser(const char *path);
| Version |
NID
|
| 0.940-3.60 |
0x9BE17A06
|
path max len : 0x3FF
int sceSblUsVerifyPupHeaderForUser(const char *path);
sceSblUsVerifyPupSegmentForUser
| Version |
NID
|
| 0.931-3.60 |
0xD47FD33E
|
path max len: 0x3FF bytes
int sceSblUsVerifyPupSegmentForUser(const char *path);
sceSblUsVerifyPupSegmentByIdForUser
| Version |
NID
|
| 0.931-3.60 |
0x95FC1A0A
|
path max len: 0x3FF bytes
Maybe that seg_id is uint64_t and so it might be part of arg2 or arg4
int sceSblUsVerifyPupSegmentByIdForUser(const char *path, void *arg2, int seg_id, int arg4);
sceSblUsVerifyPupWatermarkForUser
| Version |
NID
|
| 0.931-3.60 |
0xC6CDEB8D
|
path max len : 0x3FF bytes
int sceSblUsVerifyPupWatermarkForUser(const char *path);
sceSblUsUpdateSpackageForUser
| Version |
NID
|
| 0.931-3.60 |
0x6E8DDAC4
|
int sceSblUsUpdateSpackageForUser(int package_type, SceKernelSpackageArgs *args, int *pRequestId);
sceSblUsInspectSpackageForUser
| Version |
NID
|
| 0.931-3.60 |
0x1A39F6EE
|
int sceSblUsInspectSpackageForUser(int package_type, SceKernelSpackageArgs *args, int *pRequestId);
| Version |
NID
|
| 0.931-3.60 |
0xC1792A1C
|
int sceSblUsExtractSpackageForUser(int package_type, SceKernelSpackageArgs *args, int *pRequestId);
| Version |
NID
|
| 0.931-3.60 |
0x4897AD56
|
// node_type must be 0, 1 or 2
int sceSblUsGetExtractSpackageForUser(int node_type, int requestId, SceKernelSpackageArgs *args);
sceSblUsAllocateBufferForUser
| Version |
NID
|
| 0.931-3.60 |
0x4C06F41C
|
int sceSblUsAllocateBufferForUser(SceSize size, void **uaddr);
sceSblUsReleaseBufferForUser
| Version |
NID
|
| 0.931-3.60 |
0xBD677F5A
|
int sceSblUsReleaseBufferForUser(void *uaddr);
sceSblUsGetStatusForUser
| Version |
NID
|
| 0.931-3.60 |
0xF403143E
|
int sceSblUsGetStatusForUser(int node_type, int requestId, SceKernelSpackageArgs *args);
sceSblUsCheckSystemIntegrityForUser
| Version |
NID
|
| 0.931-3.60 |
0xBED8DFC7
|
Not implemented: does nothing.
int sceSblUsCheckSystemIntegrityForUser(void) {
int state;
if (sceSblACIsSystemProgramForKernel(0) == 0)
return 0x800F022C;
ENTER_SYSCALL(state);
EXIT_SYSCALL(state);
return 0;
}
int sceSblUsCheckSystemIntegrityForUser(void);
sceSblUsGetApplicableVersionForUser
| Version |
NID
|
| 0.931-3.60 |
0x3ADD4B7A
|
// type must be 1 or 9 else "builtin revoke list cannot be found"
int sceSblUsGetApplicableVersionForUser(int type, void *versionBuf);
SceSblSsUpdateMgr_9FC8E905
| Version |
NID
|
| 0.990 |
NOT PRESENT
|
| 3.60 |
0x9FC8E905
|
int SceSblSsUpdateMgr_9FC8E905(int arg1, int arg2, const void *src, int len);
SceSblSsUpdateMgr_D0CB50AC
| Version |
NID
|
| 0.990 |
NOT PRESENT
|
| 3.60 |
0xD0CB50AC
|
int SceSblSsUpdateMgr_D0CB50AC(int arg1, int arg2);
SceSblSsUpdateMgr_2A02DCFB
| Version |
NID
|
| 0.990 |
NOT PRESENT
|
| 3.60 |
0x2A02DCFB
|
int SceSblSsUpdateMgr_2A02DCFB(int arg1, const void *src, int len);
SceSblSsUpdateMgr_157AD4AD
| Version |
NID
|
| 0.990 |
NOT PRESENT
|
| 3.60 |
0x157AD4AD
|
int SceSblSsUpdateMgr_157AD4AD(const void *src, int len, int arg3);
SceSblSsUpdateMgr_FE930747
| Version |
NID
|
| 0.990 |
NOT PRESENT
|
| 3.60 |
0xFE930747
|
int SceSblSsUpdateMgr_FE930747(const void *src1, int len1, const void *src2, int len2);
SceSblSsUpdateMgr_92A8002B
| Version |
NID
|
| 0.990 |
NOT PRESENT
|
| 3.60 |
0x92A8002B
|
int SceSblSsUpdateMgr_92A8002B(const void *src1, int len1, const void *src2, int len2);
Update Process
The Vita updater is composed of various parts.
Initiator
The first part is the initiator of the update. The responsibility of the initiator is to copy the update file (PSP2UPDAT.PUP) to the ud0 partition and extract psp2swu.self from the update file to ud0:PSP2UPDATE/psp2swu.self. Then it signals the syscon to start in update mode, where psp2swu.self is loaded instead of the usual shell.
The initiator that most people use is likely the update option in SceSettings. Another is the update option in SceSafeMode. Another option is SceCuiSetUpper, which is extracted from the update PUP. SceCuiSetUpper is likely used in development units as it can load the update data from host0, which only exists on development units. This file, however, can be found in retail update packages. SceCuiSetUpper also sets a flag to start updater in CUI mode.
ScePsp2Swu
Once the system restarts into update mode, the updater runs. Normally, it runs in GUI mode which is the green screen with the progress bar. If a flag is set by the initiator, the updater will run in CUI mode, which is a text interface that provides more verbose information about the update process.
The updater first makes calls to SceSblSsUpdateMgr to verify the PUP header. For more information, check out PUP. Next, the updater will spawn a thread that calls into the kernel to decrypt, verify, and flash each package file according to the information found in the package header. For more information, check out PUP#Packages.
SceSblSsUpdateMgr
This is a kernel module that actually does the work and performs the update. It verifies the PUP headers as well as the package headers and then flashes the decrypted images directly to the eMMC with block writes.
Update Package Decryption Code
The following code snippet will decrypt and update a directory of package files on 1.69 (the kernel functions called are specific to 1.69 NIDs). It is an attempted reproduction of the main code in ScePsp2Swu. The requirements are that you patch the application to be running in Vsh context (or specifically patch the Authority ID to allow access to the kernel update functions). You also need an ability to read and write to the kernel from within your application. Finally, the updater will always attempt to flash the decrypted contents. If the flash failed because of model checks or whatever, it will return an error but the data will still be successfully decrypted and outputted. If it succeeds, note that you have now updated your PSVita.
int start_decryption1(int code1, unsigned char *buf, int buflen, int code2, int *phandle) {
int argst[11];
int res;
memset(argst, 0, 0x2C);
argst[0]=0x2C;
argst[1]=code1;
argst[2]=(int)buf;
argst[3]=buflen;
argst[4]=code2;
sceClibPrintf("Calling type 1 decryption with code1 = 0x%x buf = 0x%x buflen = 0x%x code2 = 0x%x \n", code1, (int)buf, buflen, code2);
res=callKernelFunction(sceSblUsUpdateSpackageForUser, code1, argst, phandle, 0);
return res;
}
int start_decryption2(int code1, unsigned char *buf, int buflen, int code2, int *phandle) {
int argst[11];
int res;
memset(argst, 0, 0x2C);
argst[0]=0x2C;
argst[1]=code1;
argst[2]=(int)buf;
argst[3]=buflen;
argst[4]=code2;
sceClibPrintf("Calling type 2 decryption with code1 = 0x%x buf = 0x%x buflen = 0x%x code2 = 0x%x\n", code1, (int)buf, buflen, code2);
res=callKernelFunction(sceSblUsInspectSpackageForUser, code1, argst, phandle, 0);
return res;
}
int start_decryption3(int code1, unsigned char *buf, int buflen, int code2, int *phandle) {
int argst[11];
int res;
memset(argst, 0, 0x2C);
argst[0]=0x2C;
argst[1]=code1;
argst[2]=(int)buf;
argst[3]=buflen;
argst[4]=code2;
sceClibPrintf("Calling type 3 decryption with code1 = 0x%x buf = 0x%x buflen = 0x%x code2 = 0x%x\n", code1, (int)buf, buflen, code2);
res=callKernelFunction(sceSblUsExtractSpackageForUser, code1, argst, phandle, 0);
return res;
}
int check_decryption_status(int code, int handle, int *out1, int *out2, int *out3, int *out4) {
int argst[11];
int res;
memset(argst, 0, 0x2C);
argst[0]=0x2C;
argst[7]=(int)out1;
argst[8]=(int)out2;
argst[9]=(int)out3;
argst[10]=(int)out4;
sceClibPrintf("Calling status with code = 0x%x handle = 0x%x\n", code, handle);
res=callKernelFunction(sceSblUsGetStatusForUser, code, handle, argst, 0);
return res;
}
int get_final_size(unsigned char *buf) {
int *poffs;
int *psize;
poffs = (int *) (buf+0x10);
psize = (int *) (buf+(*poffs)+0x20);
return *psize;
}
int get_type(unsigned char *buf) {
int *poffs;
int *psize;
if ( *(int *)buf == 0x00454353 ) // "SCE\0"
{
poffs = (int *) (buf+0x10);
psize = (int *) (buf+(*poffs)+4);
return *psize;
}
else
{
return -1;
}
}
unsigned char *get_data_offset(unsigned char *buf) {
int *poffs;
poffs = (int *) (buf+0x10);
return (buf+(*poffs)+0x80);
}
int complete_decryption(int code, int handle, unsigned char *buf, int maxlen) {
int argst[11];
int res;
unsigned char *payload;
int size;
memset(argst, 0, 0x2C);
argst[0]=0x2C;
argst[1]=code;
argst[5]=(int)buf;
argst[6]=maxlen;
sceClibPrintf("Calling complete decryption with code = 0x%x handle = 0x%x buf = 0x%x maxlen = 0x%x\n", code, handle, (int)buf, maxlen);
res=callKernelFunction(sceSblUsGetExtractSpackageForUser, code, handle, argst, 0);
return res;
}
int do_decrypt_file(const char *inpath, const char *outpath, const char *errpath, unsigned int size)
{
int fd;
int res;
int memid;
int read;
int maxlen = 0x810000;
int argst[0x2C/4];
int id;
int type;
int code;
unsigned char *src, *outbuf;
unsigned int handle, p1, p2, p3, p4;
res=callKernelFunction(sceSblUsAllocateBufferForUser, size, &src, 0, 0);
sceClibPrintf("Allocation returned 0x%x addr 0x%x\n", res, (int)src);
if(res) {
sceClibPrintf("Cannot allocate memory. (size 0x%x) fail.\n", size);
return 0;
}
//sceClibPrintf("Loading Firmware pkg file from host0:");
fd= sceIoOpen(inpath, 1, 0);
read = 0;
while ((read = sceIoRead(fd, src, size - read)) > 0);
sceIoClose(fd);
code = get_type(src);
switch (code) {
case -1:
sceClibPrintf("Not an encrypted file.\n");
goto ERROR;
case 3:
case 4:
case 0x1B:
type = 3;
res=start_decryption3(code, src, size, 9, &handle);
break;
case 0:
case 2:
case 5:
case 6:
case 7:
case 0xE:
case 0x1A:
sceClibPrintf("Warning, code %x is unsupported!\n", code);
default:
type = 2;
res=start_decryption2(code, src, size, 9, &handle);
break;
}
if(res) {
sceClibPrintf("start_decryption failed. (0x%x)\n", res);
goto ERROR;
}
for(;;) {
res=check_decryption_status(type, handle, &p1, &p2, &p3, &p4);
if(res) {
sceClibPrintf("check_decryption_status failed. (0x%x)\n", res);
goto ERROR;
}
if(p3 == 5) {
break;
} else {
sceKernelDelayThread(0x7A120);
}
}
sceClibPrintf("p1= 0x%x p2 = 0x%x p3 = 0x%x p4 = 0x%x\n", p1, p2, p3, p4);
if(p2 == 0) {
sceClibPrintf("Starting to write %s\n", outpath);
fd = sceIoOpen(outpath, 0x603, 0x186);
read = get_final_size(src);
while ((read -= sceIoWrite(fd, get_data_offset(src), read)) > 0);
sceIoClose(fd);
} else {
sceClibPrintf("Error decrypting. Writing results to %s\n", errpath);
fd= sceIoOpen(errpath, 0x603, 0x186);
read = get_final_size(src);
while ((read -= sceIoWrite(fd, get_data_offset(src), read)) > 0);
sceIoClose(fd);
goto ERROR;
}
res=complete_decryption(type, handle, src, maxlen);
if(res) {
sceClibPrintf("complete_decryption failed. (0x%x)\n", res);
goto ERROR;
}
res=callKernelFunction(sceSblUsReleaseBufferForUser, src, 0, 0, 0);
return 1;
ERROR:
res=callKernelFunction(sceSblUsReleaseBufferForUser, src, 0, 0, 0);
return 0;
}
void do_decrypt_dir(const char *path)
{
int fd;
SceIoDirent dir;
char input[256];
char output[256];
char errput[256];
if ((fd = sceIoDopen(path)) < 0)
{
sceClibPrintf("Error opening pkg dir.\n");
return;
}
while (sceIoDread(fd, &dir) > 0)
{
sprintf(input, "%s/%s", path, dir.d_name);
sprintf(output, "%s/%s.dec", path, dir.d_name);
sprintf(errput, "%s/%s.err", path, dir.d_name);
sceClibPrintf("Decrypting %s (size 0x%x)\n", input, (unsigned int)dir.d_stat.st_size);
if (do_decrypt_file(input, output, errput, (unsigned int)dir.d_stat.st_size))
sceClibPrintf("Decrypted to %s\n", output);
else
sceClibPrintf("Failed to decrypt %s\n", dir.d_name);
}
sceIoDclose(fd);
}
Bootloader
There's evidence that the bootloaders are re-encrypted with probably per-console keys during the update process. second_loader.enp and second_loader.enc are transformed into second_loader.enp_ and second_loader.enp respectively by F00D before flashing (and the same thing is done to secure_kernel).
Some useful notes
sceSblUsUpdateSpackageForUser does the bulk of the work decrypting and flashing all the update parts. There appears to be two ways to skip the version checks (but not revokion checks).
First way is to patch the imported function SceQafMgrForDriver_8C423C18(void); to return 1. Alternatively, patch Sysroot offset 0x2C+3 and set bit 0x2. This will bypass ALL version checks, including the peripherals which might be dangerous.
Update: don't do this, it does brick as expected.
Second way is to patch SceVshBridge export of vshSblAimgrIsCEX (takes no arguments) to return 0. Alternatively patch ScePsp2Swu's import of that function.
Update: this doesn't work because the export is used by other functions and fails earlier checks. This flag is set by psp2swu.self to indicate bypassing of version checks on the bootloader and system partitions. All other components will be updated if at higher version. This is what devkits do by default. You can also patch the flags directly. In sceSblUsUpdateSpackageForUser, sceSblUsInspectSpackageForUser, and sceSblUsExtractSpackageForUser (in order: flash, dry run, decrypt only) you can patch the flags argument directly and set 0x8 to indicate skipping version check on bootloader and system partitions. The flags argument found in R1 (second argument) as a user memory pointer offset 0x10.
Auth id for psp2swu.self is either 2800800000000002 or 2800800000000003.