The following is a complete directory containing direct download links for ALL the iPhone firmware files released to date, be it any model , for all your jailbreaking needs.
Note: Safari Auto-extracts these firmwares or downloads them as a zip file so either turn auto-extract off in Safari OR use firefox to download these files instead.
This list is up-to-date and will be updated as soon as any new firmware comes out.
iPhone 2G
iOS1
1.0.0: iPhone1,1_1.0_1A543a_Restore.ipsw
1.0.1: iPhone1,1_1.0.1_1C25_Restore.ipsw
1.0.2: iPhone1,1_1.0.2_1C28_Restore.ipsw
1.1.1: iPhone1,1_1.1.1_3A109a_Restore.ipsw
1.1.2: iPhone1,1_1.1.2_3B48b_Restore.ipsw
1.1.3: iPhone1,1_1.1.3_4A93_Restore.ipsw
1.1.4: iPhone1,1_1.1.4_4A102_Restore.ipsw
iOS2
2.0.0: iPhone1,1_2.0_5A347_Restore.ipsw
2.0.1: iPhone1,1_2.0.1_5B108_Restore.ipsw
2.0.2: iPhone1,1_2.0.2_5C1_Restore.ipsw
2.1.0: iPhone1,1_2.1_5F136_Restore.ipsw
2.2.0: iPhone1,1_2.2_5G77_Restore.ipsw
2.2.1: iPhone1,1_2.2.1_5H1_Restore.ipsw
iOS3
3.0.0: iPhone1,1_3.0_7A341_Restore.ipsw
3.0.1: iPhone1,1_3.0.1_7A400_Restore.ipsw
3.1.0: iPhone1,1_3.1_7C144_Restore.ipsw
3.1.2: iPhone1,1_3.1.2_7D11_Restore.ipsw
3.1.3: iPhone1,1_3.1.3_7E18_Restore.ipsw
Firmware Updates Discontinued
iPhone 3G
iOS2
2.0.0: iPhone1,2_2.0_5A347_Restore.ipsw
2.0.1: iPhone1,2_2.0.1_5B108_Restore.ipsw
2.0.2: iPhone1,2_2.0.2_5C1_Restore.ipsw
2.1.0: iPhone1,2_2.1_5F136_Restore.ipsw
2.2.0: iPhone1,2_2.2_5G77_Restore.ipsw
2.2.1: iPhone1,2_2.2.1_5H1_Restore.ipsw
iOS3
3.0.0: iPhone1,2_3.0_7A341_Restore.ipsw
3.0.1: iPhone1,2_3.0.1_7A400_Restore.ipsw
3.1.0: iPhone1,2_3.1_7C144_Restore.ipsw
3.1.2: iPhone1,2_3.1.2_7D11_Restore.ipsw
3.1.3: iPhone1,2_3.1.3_7E18_Restore.ipsw
iOS4
4.0.0: iPhone1,2_4.0_8A293_Restore.ipsw
4.0.1: iPhone1,2_4.0.1_8A306_Restore.ipsw
4.0.2: iPhone1,2_4.0.2_8A400_Restore.ipsw
4.1.0: iPhone1,2_4.1_8B117_Restore.ipsw
4.2.1: iPhone1,2_4.2.1_8C148_Restore.ipsw
Firmware Updates Discontinued
iPhone 3GS
iOS3
3.0.0: iPhone2,1_3.0_7A341_Restore.ipsw
3.0.1: iPhone2,1_3.0.1_7A400_Restore.ipsw
3.1.0: iPhone2,1_3.1_7C144_Restore.ipsw
3.1.2: iPhone2,1_3.1.2_7D11_Restore.ipsw
3.1.3: iPhone2,1_3.1.3_7E18_Restore.ipsw
iOS4
4.0.0: iPhone2,1_4.0_8A293_Restore.ipsw
4.0.1: iPhone2,1_4.0.1_8A306_Restore.ipsw
4.0.2: iPhone2,1_4.0.2_8A400_Restore.ipsw
4.1.0: iPhone2,1_4.1_8B117_Restore.ipsw
4.2.1: iPhone2,1_4.2.1_8C148a_Restore.ipsw
4.3.0: iPhone2,1_4.3_8F190_Restore.ipsw
4.3.1: iPhone2,1_4.3.1_8G4_Restore.ipsw
4.3.2: iPhone2,1_4.3.2_8H7_Restore.ipsw
4.3.3: iPhone2,1_4.3.3_8J2_Restore.ipsw
4.3.4: iPhone2,1_4.3.4_8K2_Restore.ipsw
4.3.5: iPhone2,1_4.3.5_8L1_Restore.ipsw
iPhone 4
GSM
iOS4
4.0.0: iPhone3,1_4.0_8A293_Restore.ipsw
4.0.1: iPhone3,1_4.0.1_8A306_Restore.ipsw
4.0.2: iPhone3,1_4.0.2_8A400_Restore.ipsw
4.1.0: iPhone3,1_4.1_8B117_Restore.ipsw
4.2.1: iPhone3,1_4.2.1_8C148a_Restore.ipsw
4.3.0: iPhone3,1_4.3_8F190_Restore.ipsw
4.3.1: iPhone3,1_4.3.1_8G4_Restore.ipsw
4.3.2: iPhone3,1_4.3.2_8H7_Restore.ipsw
4.3.3: iPhone3,1_4.3.3_8J2_Restore.ipsw
4.3.4: iPhone3,1_4.3.4_8K2_Restore.ipsw
4.3.5: iPhone3,1_4.3.5_8L1_Restore.ipsw
CDMA(Verizon)
iOS4
4.2.6: iPhone3,3_4.2.6_8E200_Restore.ipsw
4.2.7: iPhone3,3_4.2.7_8E303_Restore.ipsw
4.2.8: iPhone3,3_4.2.8_8E401_Restore.ipsw