verify_result User Manual

1. Overview

verify_result is a command-line verification tool for reduced-round SHA-256 and SHA-512 compression results.

The program reads a configuration file, applies the selected verification mode, computes the hash states for two candidate message blocks, and reports whether the two outputs collide.

2. Supported Features

• SHA-256 verification
• SHA-512 verification
• Free-start collision verification
• Semi-free-start collision verification
• Standard initial-value collision verification
• One-block and two-block message chaining controlled by Message_count

3. Build Instructions

Open a terminal in the verify_result directory and compile the program with:

g++ -std=c++17 main.cpp -o check_value

4. Run Instructions

Run the executable with a configuration file:

./check_value <config_file>

If no configuration file is provided, the program prints:

Usage: ./check_value <config_file>

5. Configuration File Format

The configuration file uses the format:

key: value;

Each field must appear on its own line.

Example:

Message_count: 2;
Version: SHA256;
Round: 31;
Type: Collision;
MSG0: 0x8ce3f805,0x5c401aed,0x579e5f7f,0xbc3116cb,0xca189b3c,0xeb75f04c,0x958f0a0e,0x7760b082,0xdcd5027d,0x32260ad6,0x7b12b659,0xeee66518,0xad7f88dd,0xf8ad20bb,0x7ae40ffd,0x21609249;
MSG1: 0x9abdeb1b,0x1f195f41,0x5a7210c1,0x55614f13,0xa2269dd1,0xbe888a61,0x359257d4,0xadf3737b,0x9f0484a6,0xeb830a58,0x66add94a,0x9669232d,0x45271fa5,0xb8f69585,0x428bbce3,0x0703b904;
MSG2: 0x9abdeb1b,0x1f195f41,0x5a7210c1,0x55614f13,0xa2269dd1,0xbe887a67,0x35b2dfc5,0xfde32975,0xc70595a6,0xeb838a5c,0x66add94a,0x9669232d,0x45271fa5,0xb8f69585,0x428bbce3,0x0703b904;

6. Parameter Reference

Message_count

Specifies how many message stages are used in the verification process.

Currently supported values:

• 1
• 2

Version

Selects the hash function.

Allowed values:

• SHA256
• SHA512

Round

Specifies the number of compression rounds to execute.

Type

Selects the verification mode.

Accepted forms:

• FS
• FREE_START
• FREE-START
• SFS
• SEMI_FREE_START
• SEMI-FREE-START
• Collision

IV

Required for semi-free-start verification.

IV1, IV2

Required for free-start verification.

MSG0

Required when Message_count is 2.

MSG1, MSG2

Always required.

7. Verification Modes

7.1 Free-Start Verification

When Type is FREE_START, the program:

• reads IV1
• reads IV2
• compresses MSG1 from IV1
• compresses MSG2 from IV2

7.2 Semi-Free-Start Verification

When Type is SEMI_FREE_START, the program:

• reads IV
• uses the same initial value for both message paths
• compresses MSG1 and MSG2 from that shared initial value

7.3 Standard Initial-Value Collision Verification

When Type is Collision, the program uses the built-in standard initial values:

• SHA-256 standard IV for SHA256
• SHA-512 standard IV for SHA512

No external IV, IV1, or IV2 fields are required in this mode.

8. Message_count Behavior

8.1 Message_count: 1

The program directly computes:

initial state -> MSG1
initial state -> MSG2

8.2 Message_count: 2

The program first compresses MSG0, then uses the output of MSG0 as the input state for both MSG1 and MSG2.

Flow:

initial state -> MSG0 -> intermediate state -> MSG1
initial state -> MSG0 -> intermediate state -> MSG2

In this mode, the output of MSG0 is printed so you can inspect the intermediate chaining state.

9. Output Description

The program prints:

• hash version
• message count
• round count
• verification type
• initial value or values
• MSG0 and its intermediate state when Message_count is 2
• MSG1
• MSG2
• final hash state of MSG1
• final hash state of MSG2
• collision result

The final collision result is shown as:

• Collision: YES
• Collision: NO

10. Data Requirements

• Each message block must contain exactly 16 words.
• Each SHA state must contain exactly 8 words.
• All values must be written in hexadecimal form.
• The program currently supports only Message_count = 1 and Message_count = 2.

11. Common Errors

Typical errors include:

• missing fields in the configuration file
• unsupported Version
• unsupported Type
• unsupported Message_count
• incorrect number of message words
• incorrect number of IV words

12. Example Workflow

1. Edit msg.txt.
2. Set Message_count, Version, Round, and Type.
3. Fill in IV, IV1, IV2, MSG0, MSG1, and MSG2 as required by the selected mode.
4. Compile the program.
5. Run the executable with the configuration file.
6. Check the printed outputs and the final collision result.