Using cargo with a project with dependencies on
openSUSE-release-20180903-486.1.x86_64 the following is encountered.

cargo build
...
[60] Peer certificate cannot be authenticated with given CA certificates (SSL
certificate problem: unable to get local issuer certificate)

Strace shows cargo is trying to check the following cert locations, but they
all do not exist.

Curl is able to access https://crates.io

curl seems to access: /var/lib/ca-certificates/, but in the following list it's
not there. 

this command resolves the issue.

sudo ln -s /var/lib/ca-certificates/ca-bundle.pem
/etc/pki/tls/certs/ca-bundle.crt

cargo strace output.

stat("/var/ssl", 0x7ffe105325c0)        = -1 ENOENT (No such file or directory)
stat("/usr/share/ssl", {st_mode=S_IFDIR|0755, st_size=8, ...}) = 0
stat("/usr/local/ssl", 0x7ffe105325c0)  = -1 ENOENT (No such file or directory)
stat("/usr/local/openssl", 0x7ffe105325c0) = -1 ENOENT (No such file or
directory)
stat("/usr/local/share", {st_mode=S_IFDIR|0755, st_size=0, ...}) = 0
stat("/usr/lib/ssl", 0x7ffe105325c0)    = -1 ENOENT (No such file or directory)
stat("/usr/ssl", 0x7ffe105325c0)        = -1 ENOENT (No such file or directory)
stat("/etc/openssl", 0x7ffe105325c0)    = -1 ENOENT (No such file or directory)
stat("/etc/pki/ca-trust/extracted/pem", 0x7ffe105325c0) = -1 ENOENT (No such
file or directory)
stat("/etc/pki/tls", {st_mode=S_IFDIR|0755, st_size=10, ...}) = 0
stat("/etc/ssl", {st_mode=S_IFDIR|0755, st_size=72, ...}) = 0
stat("/data/data/com.termux/files/usr/etc/tls", 0x7ffe105325c0) = -1 ENOENT (No
such file or directory)
stat("/boot/system/data/ssl", 0x7ffe105325c0) = -1 ENOENT (No such file or
directory)
stat("/usr/share/ssl/cert.pem", 0x7ffe105326d0) = -1 ENOENT (No such file or
directory)
stat("/usr/share/ssl/certs.pem", 0x7ffe105326d0) = -1 ENOENT (No such file or
directory)
stat("/usr/share/ssl/certs/ca-certificates.crt", 0x7ffe105326d0) = -1 ENOENT
(No such file or directory)
stat("/usr/share/ssl/certs/ca-root-nss.crt", 0x7ffe105326d0) = -1 ENOENT (No
such file or directory)
stat("/usr/share/ssl/certs/ca-bundle.crt", 0x7ffe105326d0) = -1 ENOENT (No such
file or directory)
stat("/usr/share/ssl/CARootCertificates.pem", 0x7ffe105326d0) = -1 ENOENT (No
such file or directory)
stat("/usr/share/ssl/tls-ca-bundle.pem", 0x7ffe105326d0) = -1 ENOENT (No such
file or directory)
stat("/usr/local/share/cert.pem", 0x7ffe105326d0) = -1 ENOENT (No such file or
directory)
stat("/usr/local/share/certs.pem", 0x7ffe105326d0) = -1 ENOENT (No such file or
directory)
stat("/usr/local/share/certs/ca-certificates.crt", 0x7ffe105326d0) = -1 ENOENT
(No such file or directory)
stat("/usr/local/share/certs/ca-root-nss.crt", 0x7ffe105326d0) = -1 ENOENT (No
such file or directory)
stat("/usr/local/share/certs/ca-bundle.crt", 0x7ffe105326d0) = -1 ENOENT (No
such file or directory)
stat("/usr/local/share/CARootCertificates.pem", 0x7ffe105326d0) = -1 ENOENT (No
such file or directory)
stat("/usr/local/share/tls-ca-bundle.pem", 0x7ffe105326d0) = -1 ENOENT (No such
file or directory)
stat("/etc/pki/tls/cert.pem", 0x7ffe105326d0) = -1 ENOENT (No such file or
directory)
stat("/etc/pki/tls/certs.pem", 0x7ffe105326d0) = -1 ENOENT (No such file or
directory)
stat("/etc/pki/tls/certs/ca-certificates.crt", 0x7ffe105326d0) = -1 ENOENT (No
such file or directory)
stat("/etc/pki/tls/certs/ca-root-nss.crt", 0x7ffe105326d0) = -1 ENOENT (No such
file or directory)
stat("/etc/pki/tls/certs/ca-bundle.crt", 0x7ffe105326d0) = -1 ENOENT (No such
file or directory)
stat("/etc/pki/tls/CARootCertificates.pem", 0x7ffe105326d0) = -1 ENOENT (No
such file or directory)
stat("/etc/pki/tls/tls-ca-bundle.pem", 0x7ffe105326d0) = -1 ENOENT (No such
file or directory)
stat("/etc/ssl/cert.pem", 0x7ffe105326d0) = -1 ENOENT (No such file or
directory)
stat("/etc/ssl/certs.pem", 0x7ffe105326d0) = -1 ENOENT (No such file or
directory)
stat("/etc/ssl/certs/ca-certificates.crt", 0x7ffe105326d0) = -1 ENOENT (No such
file or directory)
stat("/etc/ssl/certs/ca-root-nss.crt", 0x7ffe105326d0) = -1 ENOENT (No such
file or directory)
stat("/etc/ssl/certs/ca-bundle.crt", 0x7ffe105326d0) = -1 ENOENT (No such file
or directory)
stat("/etc/ssl/CARootCertificates.pem", 0x7ffe105326d0) = -1 ENOENT (No such
file or directory)
stat("/etc/ssl/tls-ca-bundle.pem", 0x7ffe105326d0) = -1 ENOENT (No such file or
directory)