Abstract: The invention provides a method and system for safely switching between product mode and development mode of a terminal, aiming at addressing the problem in the prior art that the terminal in a testing development version may be accidentally circulated into the market and cause hidden safety risk. According to the invention, different Certificate Authorities (CAs) are configured for the terminal at different stages; by storing the public-private key pairs of the certificates issued by different CAs in different secure storage media, only if the secure storage medium corresponding to the current CA state of the terminal is verified to be valid, the flags of the terminal can be successfully rewritten; a safe switching between different CA states of the terminal is realized. It is ensured that the terminal in the testing development stage cannot be used normally, thereby improving the safety of the terminal device.

Abstract: The invention provides a method and system for safely switching between product mode and development mode of a terminal, aiming at addressing the problem in the prior art that the terminal in a testing development version may be accidentally circulated into the market and cause hidden safety risk. According to the invention, different Certificate Authorities (CAs) are configured for the terminal at different stages; by storing the public-private key pairs of the certificates issued by different CAs in different secure storage media, only if the secure storage medium corresponding to the current CA state of the terminal is verified to be valid, the flags of the terminal can be successfully rewritten; a safe switching between different CA states of the terminal is realized. It is ensured that the terminal in the testing development stage cannot be used normally, thereby improving the safety of the terminal device.

Abstract: Disclosed is a key downloading method. The method comprises: sending a hardware series number (SN) and a first random number (Rnd1) to a key server; receiving a second random number (Rnd2), a first encrypted text (C1) and a key server working certificate (KSWCRT) sent by the key server; authenticating the validity of KSWCRT by using a KSRCRT; if valid, extracting a public key (PuKS) from the KSWCRT, and decrypting the first encrypted text (C1) by using the PuKS to obtain a third random number (Rnd1?); determining whether Rnd1 is consistent with Rnd1?; if consistent, encrypting the second random number (Rnd2) by using a terminal authentication public key (TKP_Pu) to generate a third encrypted text (C2?), and sending the C2? to the key server; receiving an key encrypted text (Ctmk) sent by the key server; and obtain a master key (TMK), and storing the TMK in a security control module.

Abstract: Disclosed is a key downloading method. The method comprises: sending a hardware series number (SN) and a first random number (Rnd1) to a key server; receiving a second random number (Rnd2), a first encrypted text (C1) and a key server working certificate (KSWCRT) sent by the key server; authenticating the validity of KSWCRT by using a KSRCRT; if valid, extracting a public key (PuKS) from the KSWCRT, and decrypting the first encrypted text (C1) by using the PuKS to obtain a third random number (Rnd1?); determining whether Rnd1 is consistent with Rnd1?; if consistent, encrypting the second random number (Rnd2) by using a terminal authentication public key (TKP_Pu) to generate a third encrypted text (C2?), and sending the C2? to the key server; receiving an key encrypted text (Ctmk) sent by the key server; and obtain a master key (TMK), and storing the TMK in a security control module.