Note that the URIs of the reports by the Dutch Safety Board seem to change from time to time as apparently their website gets reorganised. I'll try to keep the links in this answer up to date.
Failing that, the main page on the investigation of the crash of Flight MH17 seems to be stable enough and the reports are all linked from there. Another option is going to the main site of the Dutch Safety Board and searching for
On Tuesday, October 13, 2015, the Dutch Safety Board released the final report on their investigation of the crash of Malaysian Airlines Flight MH17.
In the report, the Board states that the plane was struck by a 9N314M warhead carried on a 9M38-series missile fired from a Buk surface-to-air missile system. The missile was fired from a region of about 320 square kilometres in the east of Ukraine.
The combination of the recorded pressure wave, the damage pattern found on the wreckage caused by blast and the impact of fragments, the bow-tie shaped
fragments found in the cockpit and in the body of one of the crew members in the cockpit, the injuries sustained by three crew members in the cockpit, the analysis of the in-flight break-up, the analysis of the explosive residues and paint found, and the size and distinct, bow-tie, shape of some the fragments, led the Dutch Safety Board to conclude that the aeroplane was struck by a 9N314M warhead as carried on a 9M38-series missile and launched by a Buk surface-to-air missile system.
3.7 Source of the damage, page 137
- The area from which the possible flight paths of a 9N314M warhead carried on a 9M38-series missile as installed on the Buk surface-to-air missile system could have commenced is about 320 square kilometres in the east of Ukraine.
- Further forensic research is required to determine the launch location. Such work falls outside the mandate of the Dutch Safety Board, both in terms of Annex 13 and the Kingdom Act ‘Dutch Safety Board’.
3.8 Simulations to assess the origin of the damage, page 147
- Simulations showed that the observed damage and the modelled fragment
pattern resulted in an estimated detonation location of the warhead to the left and above of the cockpit.
- Simulations demonstrated that the detonation of a 70 kg warhead best matched the damage observed on the wreckage of the aeroplane.
- The simulations performed indicated that the detonation location of a 9N314M warhead was in a volume of space that is less than one cubic metre and about four metres above the tip of the aeroplane’s nose on the left side of the cockpit.
- The damage to the wreckage recovered was consistent with the predictions made by the simulation of the blast caused by the detonation of a 70 kg warhead.
The above mentioned findings are consistent with the conclusion of the Dutch Safety Board that flight MH17 was struck by a 9N314M warhead as carried on a 9M38 series missile and launched by a Buk surface-to-air missile system.
3.10 Summary of the results of the simulations into the causes of the crash, page 150
Also, in MH17 About the investigation, the Board states:
The Russian Federation indicated that the aeroplane was downed by a missile that could have been fired from either the ground or an aeroplane. This standpoint deviated from what was jointly subscribed during the first and second meetings (also by the Russian Federation). The third meeting was closed with the joint conclusion (thus by the Russian Federation as well) that the aeroplane was hit by high-energy objects of a missile that detonated in front of and to the left of the cockpit. This joint conclusion is less far-reaching than the conclusions in the investigation report on the crash of flight MH17.
1.4 Conducting the investigation, page 20
So even the least far-reaching conclusion that all parties to the investigation agree on, is that
flight MH17 was shot down by a missile.
Additionally, the plane has been partially reconstructed in a hangar on the Gilze-Rijen airbase out of the found wreckage. It was shown at the release of the report. It was open to next of kin and journalists; I don't know if it is or has been open to the general public.
On 26 May 2021, the judges in the criminal trial inspected the wreckage on that site, which was widely reported on (in Dutch) and even live streamed.
My original answer, based on the preliminary report:
The preliminary report on the crash by the Dutch Safety Board reads:
Based on the preliminary findings to date, no indications of any technical or operational issues were found with the aircraft or crew prior to the ending of the CVR and FDR recording at 13.20:03 hrs.
The damage observed in the forward section of the aircraft appears to indicate that the aircraft was penetrated by a large number of high-energy objects from outside the aircraft. It is likely that this damage resulted in a loss of structural integrity of the aircraft, leading to an in-flight break up.
Preliminary report - Crash involving Malaysia Airlines Boeing 777-200 flight MH17, chapter 3, Summary of findings, page 30
This indicates that flight MH17 was indeed shot down.