= oldauth: certtostr, pktostr, sktostr, strtocert, strtopk, strtosk, sign, verify, readauthinfo, writeauthinfo: encoding for original Inferno authentication protocol include "ipints.m"; include "crypt.m"; include "oldauth.m"; oldauth := load Oldauth Oldauth->PATH; Certificate: adt { sa: string; ha: string; signer: string; exp: int; sig: ref Crypt->PKsig; }; Authinfo: adt { mysk: ref Crypt->SK; mypk: ref Crypt->PK; owner: string; cert: ref Certificate; spk: ref Crypt->PK; alpha: ref IPints->IPint; p: ref IPints->IPint; }; sign: fn (sk: ref Crypt->SK, signer: string, exp: int, state: ref Crypt->DigestState, ha: string): ref Certificate; verify: fn (pk: ref Crypt->PK, cert: ref Certificate, state: ref Crypt->DigestState): int; strtocert: fn(s: string): ref Certificate; certtostr: fn(c: ref Certificate): string; strtopk: fn(s: string): (ref Crypt->PK, string); pktostr: fn(pk: ref Crypt->PK, owner: string): string; strtosk: fn(s: string): (ref Crypt->SK, string); sktostr: fn(sk: ref Crypt->SK, owner: string): string; readauthinfo: fn(filename: string): ref Authinfo; writeauthinfo: fn(filename: string, info: ref Authinfo): int; Certificates, public keys, and private keys are passed over networks and between applications using a Unicode representa‐ tion. This collection of functions provide a means to con‐ vert adts supplied by the system to and from their portable textual representation. These routines are used by login(2) and factotum(4) to implement the Inferno authentication pro‐ tocol. Public and private keys are represented by Crypt->PK and Crypt->SK (see keyring-intro(2)). An authentication domain is represented by the public key of the domain's signer, typ‐ ically in control of a keyfs(4) and running a logind(8). Two adts associate a public/private key pair with a user name within a specific authentication domain: Authinfo The Authinfo adt contains an individual user's private and public key, a human-readable name for the key (eg, a user name), the signer's certificate and the signer's public key, and the Diffie-Hellman parame‐ ters. The signer's certificate binds the user's pub‐ lic key to the given key name in the signer's domain. Certificate The Certificate adt contains a digital signature with the certification of the trusted authority (CA). The signature covers not only the user's public key, but the key's name, the signer's name and the expiration time of the certificate. Both the key's name and the signer's name are local to the signer's domain. Init must be called before using any other operation in the module. Sign returns a Certificate containing the digital signature using secret key sk of a digest's state, which is the output of the hash algorithm named ha, combined with the hash of the signer's name, and the certificate's expiration time (in sec‐ onds from the Epoch). Valid hash algorithms are sha1 and md5. The expiry time should be zero if the certificate does not expire. Typically the state is the result of hashing array of byte pktostr(pk, username) for a given public key pk that is associated with the given username by the signer. Verify checks that the given Certificate is the result of signing the given state using the secret (private) key corre‐ sponding to public key pk. It returns true (non-zero) if the certificate is valid, including the signer's name, and the expiration time; the caller must enforce the expiration time if desired. It returns false (zero) if the certificate is invalid. Sign creates a digital signature of a digest from the con‐ catenation of: a message, the name of the signer, and an expiration time. State is the digest state after running sha1, md4 or md5 over the message. Ha is a string specifying the hash algorithm to use: "sha", "sha1", "md4" or "md5". Sign extends the digest to cover the signer's name (taken from the private key, sk) and the expiration time. It returns a certificate containing the digital signature of the digest, signer name, hash algorithm and signature algorithm. If any parameter is invalid, sign returns nil. The signature algorithm is implied by the type of the private key. Verify uses public key pk to verify a certificate. It returns non-zero (true) if the certificate is valid; zero (false) otherwise. State is the digest state after running the chosen digest algorithm over the message. The remaining operations fetch and store those values and convert to and from text representations for use in protocols and for storage. Strtocert takes a string argument containing a varying number of newline-separated fields: a signature algorithm, a hash algorithm, a signer's name, an expiration time, and values representing a digital signature. It returns the correspond‐ ing Certificate. If the string is of improper format, the result is nil. Certtostr performs the inverse operation: takes the Certifi‐ cate c and produces a text string suitable for communication over a network. Note that the string will contain newline characters. Strtopk and strtosk take as their arguments a string s repre‐ senting the public and private keys respectively. S contains an algorithm name, a user name and values representing the key. Each returns a tuple (k, s), where k is the resulting key value (ie, Crypt->PK or Crypt->SK) and s is a string giv‐ ing the name associated with the key, typically a user name. If the format of s is invalid, k is nil, and s contains a diagnostic. Pktostr and sktostr perform the inverse operations: they take a public key (secret key) pk or sk, the owner name to be associated with that key, and produce a printable representa‐ tion as a string. The owner names the user that owns the key; in the case of a public key, the user is expected to possess the corresponding private key. Readauthinfo reads a representation of an Authinfo from a file. It returns nil if there is a read error or a conver‐ sion error; it returns a reference to the Authinfo otherwise. Writeauthinfo writes a representation of info to a file. It returns -1 if the write operation fails, 0 otherwise. == source /appl/lib/oldauth.b == see ALSO crypt-intro(2), ipints(2), security-intro(2)